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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/hv
Initial import
Diffstat (limited to 'drivers/hv')
-rw-r--r--drivers/hv/Kconfig22
-rw-r--r--drivers/hv/Makefile8
-rw-r--r--drivers/hv/channel.c956
-rw-r--r--drivers/hv/channel_mgmt.c862
-rw-r--r--drivers/hv/connection.c480
-rw-r--r--drivers/hv/hv.c535
-rw-r--r--drivers/hv/hv_balloon.c1616
-rw-r--r--drivers/hv/hv_fcopy.c441
-rw-r--r--drivers/hv/hv_kvp.c722
-rw-r--r--drivers/hv/hv_snapshot.c303
-rw-r--r--drivers/hv/hv_util.c447
-rw-r--r--drivers/hv/hyperv_vmbus.h738
-rw-r--r--drivers/hv/ring_buffer.c566
-rw-r--r--drivers/hv/vmbus_drv.c1114
14 files changed, 8810 insertions, 0 deletions
diff --git a/drivers/hv/Kconfig b/drivers/hv/Kconfig
new file mode 100644
index 000000000..0403b51d2
--- /dev/null
+++ b/drivers/hv/Kconfig
@@ -0,0 +1,22 @@
+menu "Microsoft Hyper-V guest support"
+
+config HYPERV
+ tristate "Microsoft Hyper-V client drivers"
+ depends on X86 && ACPI && PCI && X86_LOCAL_APIC && HYPERVISOR_GUEST
+ help
+ Select this option to run Linux as a Hyper-V client operating
+ system.
+
+config HYPERV_UTILS
+ tristate "Microsoft Hyper-V Utilities driver"
+ depends on HYPERV && CONNECTOR && NLS
+ help
+ Select this option to enable the Hyper-V Utilities.
+
+config HYPERV_BALLOON
+ tristate "Microsoft Hyper-V Balloon driver"
+ depends on HYPERV
+ help
+ Select this option to enable Hyper-V Balloon driver.
+
+endmenu
diff --git a/drivers/hv/Makefile b/drivers/hv/Makefile
new file mode 100644
index 000000000..5e4dfa4cf
--- /dev/null
+++ b/drivers/hv/Makefile
@@ -0,0 +1,8 @@
+obj-$(CONFIG_HYPERV) += hv_vmbus.o
+obj-$(CONFIG_HYPERV_UTILS) += hv_utils.o
+obj-$(CONFIG_HYPERV_BALLOON) += hv_balloon.o
+
+hv_vmbus-y := vmbus_drv.o \
+ hv.o connection.o channel.o \
+ channel_mgmt.o ring_buffer.o
+hv_utils-y := hv_util.o hv_kvp.o hv_snapshot.o hv_fcopy.o
diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
new file mode 100644
index 000000000..54da66dc7
--- /dev/null
+++ b/drivers/hv/channel.c
@@ -0,0 +1,956 @@
+/*
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ * Haiyang Zhang <haiyangz@microsoft.com>
+ * Hank Janssen <hjanssen@microsoft.com>
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/hyperv.h>
+#include <linux/uio.h>
+
+#include "hyperv_vmbus.h"
+
+#define NUM_PAGES_SPANNED(addr, len) \
+((PAGE_ALIGN(addr + len) >> PAGE_SHIFT) - (addr >> PAGE_SHIFT))
+
+/*
+ * vmbus_setevent- Trigger an event notification on the specified
+ * channel.
+ */
+static void vmbus_setevent(struct vmbus_channel *channel)
+{
+ struct hv_monitor_page *monitorpage;
+
+ if (channel->offermsg.monitor_allocated) {
+ /* Each u32 represents 32 channels */
+ sync_set_bit(channel->offermsg.child_relid & 31,
+ (unsigned long *) vmbus_connection.send_int_page +
+ (channel->offermsg.child_relid >> 5));
+
+ /* Get the child to parent monitor page */
+ monitorpage = vmbus_connection.monitor_pages[1];
+
+ sync_set_bit(channel->monitor_bit,
+ (unsigned long *)&monitorpage->trigger_group
+ [channel->monitor_grp].pending);
+
+ } else {
+ vmbus_set_event(channel);
+ }
+}
+
+/*
+ * vmbus_open - Open the specified channel.
+ */
+int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size,
+ u32 recv_ringbuffer_size, void *userdata, u32 userdatalen,
+ void (*onchannelcallback)(void *context), void *context)
+{
+ struct vmbus_channel_open_channel *open_msg;
+ struct vmbus_channel_msginfo *open_info = NULL;
+ void *in, *out;
+ unsigned long flags;
+ int ret, err = 0;
+ unsigned long t;
+
+ spin_lock_irqsave(&newchannel->lock, flags);
+ if (newchannel->state == CHANNEL_OPEN_STATE) {
+ newchannel->state = CHANNEL_OPENING_STATE;
+ } else {
+ spin_unlock_irqrestore(&newchannel->lock, flags);
+ return -EINVAL;
+ }
+ spin_unlock_irqrestore(&newchannel->lock, flags);
+
+ newchannel->onchannel_callback = onchannelcallback;
+ newchannel->channel_callback_context = context;
+
+ /* Allocate the ring buffer */
+ out = (void *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
+ get_order(send_ringbuffer_size + recv_ringbuffer_size));
+
+ if (!out) {
+ err = -ENOMEM;
+ goto error0;
+ }
+
+ in = (void *)((unsigned long)out + send_ringbuffer_size);
+
+ newchannel->ringbuffer_pages = out;
+ newchannel->ringbuffer_pagecount = (send_ringbuffer_size +
+ recv_ringbuffer_size) >> PAGE_SHIFT;
+
+ ret = hv_ringbuffer_init(
+ &newchannel->outbound, out, send_ringbuffer_size);
+
+ if (ret != 0) {
+ err = ret;
+ goto error0;
+ }
+
+ ret = hv_ringbuffer_init(
+ &newchannel->inbound, in, recv_ringbuffer_size);
+ if (ret != 0) {
+ err = ret;
+ goto error0;
+ }
+
+
+ /* Establish the gpadl for the ring buffer */
+ newchannel->ringbuffer_gpadlhandle = 0;
+
+ ret = vmbus_establish_gpadl(newchannel,
+ newchannel->outbound.ring_buffer,
+ send_ringbuffer_size +
+ recv_ringbuffer_size,
+ &newchannel->ringbuffer_gpadlhandle);
+
+ if (ret != 0) {
+ err = ret;
+ goto error0;
+ }
+
+ /* Create and init the channel open message */
+ open_info = kmalloc(sizeof(*open_info) +
+ sizeof(struct vmbus_channel_open_channel),
+ GFP_KERNEL);
+ if (!open_info) {
+ err = -ENOMEM;
+ goto error_gpadl;
+ }
+
+ init_completion(&open_info->waitevent);
+
+ open_msg = (struct vmbus_channel_open_channel *)open_info->msg;
+ open_msg->header.msgtype = CHANNELMSG_OPENCHANNEL;
+ open_msg->openid = newchannel->offermsg.child_relid;
+ open_msg->child_relid = newchannel->offermsg.child_relid;
+ open_msg->ringbuffer_gpadlhandle = newchannel->ringbuffer_gpadlhandle;
+ open_msg->downstream_ringbuffer_pageoffset = send_ringbuffer_size >>
+ PAGE_SHIFT;
+ open_msg->target_vp = newchannel->target_vp;
+
+ if (userdatalen > MAX_USER_DEFINED_BYTES) {
+ err = -EINVAL;
+ goto error_gpadl;
+ }
+
+ if (userdatalen)
+ memcpy(open_msg->userdata, userdata, userdatalen);
+
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+ list_add_tail(&open_info->msglistentry,
+ &vmbus_connection.chn_msg_list);
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+
+ ret = vmbus_post_msg(open_msg,
+ sizeof(struct vmbus_channel_open_channel));
+
+ if (ret != 0) {
+ err = ret;
+ goto error1;
+ }
+
+ t = wait_for_completion_timeout(&open_info->waitevent, 5*HZ);
+ if (t == 0) {
+ err = -ETIMEDOUT;
+ goto error1;
+ }
+
+
+ if (open_info->response.open_result.status)
+ err = open_info->response.open_result.status;
+
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+ list_del(&open_info->msglistentry);
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+
+ if (err == 0)
+ newchannel->state = CHANNEL_OPENED_STATE;
+
+ kfree(open_info);
+ return err;
+
+error1:
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+ list_del(&open_info->msglistentry);
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+
+error_gpadl:
+ vmbus_teardown_gpadl(newchannel, newchannel->ringbuffer_gpadlhandle);
+
+error0:
+ free_pages((unsigned long)out,
+ get_order(send_ringbuffer_size + recv_ringbuffer_size));
+ kfree(open_info);
+ newchannel->state = CHANNEL_OPEN_STATE;
+ return err;
+}
+EXPORT_SYMBOL_GPL(vmbus_open);
+
+/*
+ * create_gpadl_header - Creates a gpadl for the specified buffer
+ */
+static int create_gpadl_header(void *kbuffer, u32 size,
+ struct vmbus_channel_msginfo **msginfo,
+ u32 *messagecount)
+{
+ int i;
+ int pagecount;
+ struct vmbus_channel_gpadl_header *gpadl_header;
+ struct vmbus_channel_gpadl_body *gpadl_body;
+ struct vmbus_channel_msginfo *msgheader;
+ struct vmbus_channel_msginfo *msgbody = NULL;
+ u32 msgsize;
+
+ int pfnsum, pfncount, pfnleft, pfncurr, pfnsize;
+
+ pagecount = size >> PAGE_SHIFT;
+
+ /* do we need a gpadl body msg */
+ pfnsize = MAX_SIZE_CHANNEL_MESSAGE -
+ sizeof(struct vmbus_channel_gpadl_header) -
+ sizeof(struct gpa_range);
+ pfncount = pfnsize / sizeof(u64);
+
+ if (pagecount > pfncount) {
+ /* we need a gpadl body */
+ /* fill in the header */
+ msgsize = sizeof(struct vmbus_channel_msginfo) +
+ sizeof(struct vmbus_channel_gpadl_header) +
+ sizeof(struct gpa_range) + pfncount * sizeof(u64);
+ msgheader = kzalloc(msgsize, GFP_KERNEL);
+ if (!msgheader)
+ goto nomem;
+
+ INIT_LIST_HEAD(&msgheader->submsglist);
+ msgheader->msgsize = msgsize;
+
+ gpadl_header = (struct vmbus_channel_gpadl_header *)
+ msgheader->msg;
+ gpadl_header->rangecount = 1;
+ gpadl_header->range_buflen = sizeof(struct gpa_range) +
+ pagecount * sizeof(u64);
+ gpadl_header->range[0].byte_offset = 0;
+ gpadl_header->range[0].byte_count = size;
+ for (i = 0; i < pfncount; i++)
+ gpadl_header->range[0].pfn_array[i] = slow_virt_to_phys(
+ kbuffer + PAGE_SIZE * i) >> PAGE_SHIFT;
+ *msginfo = msgheader;
+ *messagecount = 1;
+
+ pfnsum = pfncount;
+ pfnleft = pagecount - pfncount;
+
+ /* how many pfns can we fit */
+ pfnsize = MAX_SIZE_CHANNEL_MESSAGE -
+ sizeof(struct vmbus_channel_gpadl_body);
+ pfncount = pfnsize / sizeof(u64);
+
+ /* fill in the body */
+ while (pfnleft) {
+ if (pfnleft > pfncount)
+ pfncurr = pfncount;
+ else
+ pfncurr = pfnleft;
+
+ msgsize = sizeof(struct vmbus_channel_msginfo) +
+ sizeof(struct vmbus_channel_gpadl_body) +
+ pfncurr * sizeof(u64);
+ msgbody = kzalloc(msgsize, GFP_KERNEL);
+
+ if (!msgbody) {
+ struct vmbus_channel_msginfo *pos = NULL;
+ struct vmbus_channel_msginfo *tmp = NULL;
+ /*
+ * Free up all the allocated messages.
+ */
+ list_for_each_entry_safe(pos, tmp,
+ &msgheader->submsglist,
+ msglistentry) {
+
+ list_del(&pos->msglistentry);
+ kfree(pos);
+ }
+
+ goto nomem;
+ }
+
+ msgbody->msgsize = msgsize;
+ (*messagecount)++;
+ gpadl_body =
+ (struct vmbus_channel_gpadl_body *)msgbody->msg;
+
+ /*
+ * Gpadl is u32 and we are using a pointer which could
+ * be 64-bit
+ * This is governed by the guest/host protocol and
+ * so the hypervisor gurantees that this is ok.
+ */
+ for (i = 0; i < pfncurr; i++)
+ gpadl_body->pfn[i] = slow_virt_to_phys(
+ kbuffer + PAGE_SIZE * (pfnsum + i)) >>
+ PAGE_SHIFT;
+
+ /* add to msg header */
+ list_add_tail(&msgbody->msglistentry,
+ &msgheader->submsglist);
+ pfnsum += pfncurr;
+ pfnleft -= pfncurr;
+ }
+ } else {
+ /* everything fits in a header */
+ msgsize = sizeof(struct vmbus_channel_msginfo) +
+ sizeof(struct vmbus_channel_gpadl_header) +
+ sizeof(struct gpa_range) + pagecount * sizeof(u64);
+ msgheader = kzalloc(msgsize, GFP_KERNEL);
+ if (msgheader == NULL)
+ goto nomem;
+ msgheader->msgsize = msgsize;
+
+ gpadl_header = (struct vmbus_channel_gpadl_header *)
+ msgheader->msg;
+ gpadl_header->rangecount = 1;
+ gpadl_header->range_buflen = sizeof(struct gpa_range) +
+ pagecount * sizeof(u64);
+ gpadl_header->range[0].byte_offset = 0;
+ gpadl_header->range[0].byte_count = size;
+ for (i = 0; i < pagecount; i++)
+ gpadl_header->range[0].pfn_array[i] = slow_virt_to_phys(
+ kbuffer + PAGE_SIZE * i) >> PAGE_SHIFT;
+
+ *msginfo = msgheader;
+ *messagecount = 1;
+ }
+
+ return 0;
+nomem:
+ kfree(msgheader);
+ kfree(msgbody);
+ return -ENOMEM;
+}
+
+/*
+ * vmbus_establish_gpadl - Estabish a GPADL for the specified buffer
+ *
+ * @channel: a channel
+ * @kbuffer: from kmalloc or vmalloc
+ * @size: page-size multiple
+ * @gpadl_handle: some funky thing
+ */
+int vmbus_establish_gpadl(struct vmbus_channel *channel, void *kbuffer,
+ u32 size, u32 *gpadl_handle)
+{
+ struct vmbus_channel_gpadl_header *gpadlmsg;
+ struct vmbus_channel_gpadl_body *gpadl_body;
+ struct vmbus_channel_msginfo *msginfo = NULL;
+ struct vmbus_channel_msginfo *submsginfo;
+ u32 msgcount;
+ struct list_head *curr;
+ u32 next_gpadl_handle;
+ unsigned long flags;
+ int ret = 0;
+
+ next_gpadl_handle =
+ (atomic_inc_return(&vmbus_connection.next_gpadl_handle) - 1);
+
+ ret = create_gpadl_header(kbuffer, size, &msginfo, &msgcount);
+ if (ret)
+ return ret;
+
+ init_completion(&msginfo->waitevent);
+
+ gpadlmsg = (struct vmbus_channel_gpadl_header *)msginfo->msg;
+ gpadlmsg->header.msgtype = CHANNELMSG_GPADL_HEADER;
+ gpadlmsg->child_relid = channel->offermsg.child_relid;
+ gpadlmsg->gpadl = next_gpadl_handle;
+
+
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+ list_add_tail(&msginfo->msglistentry,
+ &vmbus_connection.chn_msg_list);
+
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+
+ ret = vmbus_post_msg(gpadlmsg, msginfo->msgsize -
+ sizeof(*msginfo));
+ if (ret != 0)
+ goto cleanup;
+
+ if (msgcount > 1) {
+ list_for_each(curr, &msginfo->submsglist) {
+
+ submsginfo = (struct vmbus_channel_msginfo *)curr;
+ gpadl_body =
+ (struct vmbus_channel_gpadl_body *)submsginfo->msg;
+
+ gpadl_body->header.msgtype =
+ CHANNELMSG_GPADL_BODY;
+ gpadl_body->gpadl = next_gpadl_handle;
+
+ ret = vmbus_post_msg(gpadl_body,
+ submsginfo->msgsize -
+ sizeof(*submsginfo));
+ if (ret != 0)
+ goto cleanup;
+
+ }
+ }
+ wait_for_completion(&msginfo->waitevent);
+
+ /* At this point, we received the gpadl created msg */
+ *gpadl_handle = gpadlmsg->gpadl;
+
+cleanup:
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+ list_del(&msginfo->msglistentry);
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+
+ kfree(msginfo);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vmbus_establish_gpadl);
+
+/*
+ * vmbus_teardown_gpadl -Teardown the specified GPADL handle
+ */
+int vmbus_teardown_gpadl(struct vmbus_channel *channel, u32 gpadl_handle)
+{
+ struct vmbus_channel_gpadl_teardown *msg;
+ struct vmbus_channel_msginfo *info;
+ unsigned long flags;
+ int ret;
+
+ info = kmalloc(sizeof(*info) +
+ sizeof(struct vmbus_channel_gpadl_teardown), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ init_completion(&info->waitevent);
+
+ msg = (struct vmbus_channel_gpadl_teardown *)info->msg;
+
+ msg->header.msgtype = CHANNELMSG_GPADL_TEARDOWN;
+ msg->child_relid = channel->offermsg.child_relid;
+ msg->gpadl = gpadl_handle;
+
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+ list_add_tail(&info->msglistentry,
+ &vmbus_connection.chn_msg_list);
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+ ret = vmbus_post_msg(msg,
+ sizeof(struct vmbus_channel_gpadl_teardown));
+
+ if (ret)
+ goto post_msg_err;
+
+ wait_for_completion(&info->waitevent);
+
+post_msg_err:
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+ list_del(&info->msglistentry);
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+
+ kfree(info);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vmbus_teardown_gpadl);
+
+static void reset_channel_cb(void *arg)
+{
+ struct vmbus_channel *channel = arg;
+
+ channel->onchannel_callback = NULL;
+}
+
+static int vmbus_close_internal(struct vmbus_channel *channel)
+{
+ struct vmbus_channel_close_channel *msg;
+ int ret;
+
+ channel->state = CHANNEL_OPEN_STATE;
+ channel->sc_creation_callback = NULL;
+ /* Stop callback and cancel the timer asap */
+ if (channel->target_cpu != get_cpu()) {
+ put_cpu();
+ smp_call_function_single(channel->target_cpu, reset_channel_cb,
+ channel, true);
+ } else {
+ reset_channel_cb(channel);
+ put_cpu();
+ }
+
+ /* Send a closing message */
+
+ msg = &channel->close_msg.msg;
+
+ msg->header.msgtype = CHANNELMSG_CLOSECHANNEL;
+ msg->child_relid = channel->offermsg.child_relid;
+
+ ret = vmbus_post_msg(msg, sizeof(struct vmbus_channel_close_channel));
+
+ if (ret) {
+ pr_err("Close failed: close post msg return is %d\n", ret);
+ /*
+ * If we failed to post the close msg,
+ * it is perhaps better to leak memory.
+ */
+ return ret;
+ }
+
+ /* Tear down the gpadl for the channel's ring buffer */
+ if (channel->ringbuffer_gpadlhandle) {
+ ret = vmbus_teardown_gpadl(channel,
+ channel->ringbuffer_gpadlhandle);
+ if (ret) {
+ pr_err("Close failed: teardown gpadl return %d\n", ret);
+ /*
+ * If we failed to teardown gpadl,
+ * it is perhaps better to leak memory.
+ */
+ return ret;
+ }
+ }
+
+ /* Cleanup the ring buffers for this channel */
+ hv_ringbuffer_cleanup(&channel->outbound);
+ hv_ringbuffer_cleanup(&channel->inbound);
+
+ free_pages((unsigned long)channel->ringbuffer_pages,
+ get_order(channel->ringbuffer_pagecount * PAGE_SIZE));
+
+ /*
+ * If the channel has been rescinded; process device removal.
+ */
+ if (channel->rescind)
+ hv_process_channel_removal(channel,
+ channel->offermsg.child_relid);
+ return ret;
+}
+
+/*
+ * vmbus_close - Close the specified channel
+ */
+void vmbus_close(struct vmbus_channel *channel)
+{
+ struct list_head *cur, *tmp;
+ struct vmbus_channel *cur_channel;
+
+ if (channel->primary_channel != NULL) {
+ /*
+ * We will only close sub-channels when
+ * the primary is closed.
+ */
+ return;
+ }
+ /*
+ * Close all the sub-channels first and then close the
+ * primary channel.
+ */
+ list_for_each_safe(cur, tmp, &channel->sc_list) {
+ cur_channel = list_entry(cur, struct vmbus_channel, sc_list);
+ if (cur_channel->state != CHANNEL_OPENED_STATE)
+ continue;
+ vmbus_close_internal(cur_channel);
+ }
+ /*
+ * Now close the primary.
+ */
+ vmbus_close_internal(channel);
+}
+EXPORT_SYMBOL_GPL(vmbus_close);
+
+int vmbus_sendpacket_ctl(struct vmbus_channel *channel, void *buffer,
+ u32 bufferlen, u64 requestid,
+ enum vmbus_packet_type type, u32 flags, bool kick_q)
+{
+ struct vmpacket_descriptor desc;
+ u32 packetlen = sizeof(struct vmpacket_descriptor) + bufferlen;
+ u32 packetlen_aligned = ALIGN(packetlen, sizeof(u64));
+ struct kvec bufferlist[3];
+ u64 aligned_data = 0;
+ int ret;
+ bool signal = false;
+
+
+ /* Setup the descriptor */
+ desc.type = type; /* VmbusPacketTypeDataInBand; */
+ desc.flags = flags; /* VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED; */
+ /* in 8-bytes granularity */
+ desc.offset8 = sizeof(struct vmpacket_descriptor) >> 3;
+ desc.len8 = (u16)(packetlen_aligned >> 3);
+ desc.trans_id = requestid;
+
+ bufferlist[0].iov_base = &desc;
+ bufferlist[0].iov_len = sizeof(struct vmpacket_descriptor);
+ bufferlist[1].iov_base = buffer;
+ bufferlist[1].iov_len = bufferlen;
+ bufferlist[2].iov_base = &aligned_data;
+ bufferlist[2].iov_len = (packetlen_aligned - packetlen);
+
+ ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
+
+ /*
+ * Signalling the host is conditional on many factors:
+ * 1. The ring state changed from being empty to non-empty.
+ * This is tracked by the variable "signal".
+ * 2. The variable kick_q tracks if more data will be placed
+ * on the ring. We will not signal if more data is
+ * to be placed.
+ *
+ * If we cannot write to the ring-buffer; signal the host
+ * even if we may not have written anything. This is a rare
+ * enough condition that it should not matter.
+ */
+ if (((ret == 0) && kick_q && signal) || (ret))
+ vmbus_setevent(channel);
+
+ return ret;
+}
+EXPORT_SYMBOL(vmbus_sendpacket_ctl);
+
+/**
+ * vmbus_sendpacket() - Send the specified buffer on the given channel
+ * @channel: Pointer to vmbus_channel structure.
+ * @buffer: Pointer to the buffer you want to receive the data into.
+ * @bufferlen: Maximum size of what the the buffer will hold
+ * @requestid: Identifier of the request
+ * @type: Type of packet that is being send e.g. negotiate, time
+ * packet etc.
+ *
+ * Sends data in @buffer directly to hyper-v via the vmbus
+ * This will send the data unparsed to hyper-v.
+ *
+ * Mainly used by Hyper-V drivers.
+ */
+int vmbus_sendpacket(struct vmbus_channel *channel, void *buffer,
+ u32 bufferlen, u64 requestid,
+ enum vmbus_packet_type type, u32 flags)
+{
+ return vmbus_sendpacket_ctl(channel, buffer, bufferlen, requestid,
+ type, flags, true);
+}
+EXPORT_SYMBOL(vmbus_sendpacket);
+
+/*
+ * vmbus_sendpacket_pagebuffer_ctl - Send a range of single-page buffer
+ * packets using a GPADL Direct packet type. This interface allows you
+ * to control notifying the host. This will be useful for sending
+ * batched data. Also the sender can control the send flags
+ * explicitly.
+ */
+int vmbus_sendpacket_pagebuffer_ctl(struct vmbus_channel *channel,
+ struct hv_page_buffer pagebuffers[],
+ u32 pagecount, void *buffer, u32 bufferlen,
+ u64 requestid,
+ u32 flags,
+ bool kick_q)
+{
+ int ret;
+ int i;
+ struct vmbus_channel_packet_page_buffer desc;
+ u32 descsize;
+ u32 packetlen;
+ u32 packetlen_aligned;
+ struct kvec bufferlist[3];
+ u64 aligned_data = 0;
+ bool signal = false;
+
+ if (pagecount > MAX_PAGE_BUFFER_COUNT)
+ return -EINVAL;
+
+
+ /*
+ * Adjust the size down since vmbus_channel_packet_page_buffer is the
+ * largest size we support
+ */
+ descsize = sizeof(struct vmbus_channel_packet_page_buffer) -
+ ((MAX_PAGE_BUFFER_COUNT - pagecount) *
+ sizeof(struct hv_page_buffer));
+ packetlen = descsize + bufferlen;
+ packetlen_aligned = ALIGN(packetlen, sizeof(u64));
+
+ /* Setup the descriptor */
+ desc.type = VM_PKT_DATA_USING_GPA_DIRECT;
+ desc.flags = flags;
+ desc.dataoffset8 = descsize >> 3; /* in 8-bytes grandularity */
+ desc.length8 = (u16)(packetlen_aligned >> 3);
+ desc.transactionid = requestid;
+ desc.rangecount = pagecount;
+
+ for (i = 0; i < pagecount; i++) {
+ desc.range[i].len = pagebuffers[i].len;
+ desc.range[i].offset = pagebuffers[i].offset;
+ desc.range[i].pfn = pagebuffers[i].pfn;
+ }
+
+ bufferlist[0].iov_base = &desc;
+ bufferlist[0].iov_len = descsize;
+ bufferlist[1].iov_base = buffer;
+ bufferlist[1].iov_len = bufferlen;
+ bufferlist[2].iov_base = &aligned_data;
+ bufferlist[2].iov_len = (packetlen_aligned - packetlen);
+
+ ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
+
+ /*
+ * Signalling the host is conditional on many factors:
+ * 1. The ring state changed from being empty to non-empty.
+ * This is tracked by the variable "signal".
+ * 2. The variable kick_q tracks if more data will be placed
+ * on the ring. We will not signal if more data is
+ * to be placed.
+ *
+ * If we cannot write to the ring-buffer; signal the host
+ * even if we may not have written anything. This is a rare
+ * enough condition that it should not matter.
+ */
+ if (((ret == 0) && kick_q && signal) || (ret))
+ vmbus_setevent(channel);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vmbus_sendpacket_pagebuffer_ctl);
+
+/*
+ * vmbus_sendpacket_pagebuffer - Send a range of single-page buffer
+ * packets using a GPADL Direct packet type.
+ */
+int vmbus_sendpacket_pagebuffer(struct vmbus_channel *channel,
+ struct hv_page_buffer pagebuffers[],
+ u32 pagecount, void *buffer, u32 bufferlen,
+ u64 requestid)
+{
+ u32 flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
+ return vmbus_sendpacket_pagebuffer_ctl(channel, pagebuffers, pagecount,
+ buffer, bufferlen, requestid,
+ flags, true);
+
+}
+EXPORT_SYMBOL_GPL(vmbus_sendpacket_pagebuffer);
+
+/*
+ * vmbus_sendpacket_multipagebuffer - Send a multi-page buffer packet
+ * using a GPADL Direct packet type.
+ * The buffer includes the vmbus descriptor.
+ */
+int vmbus_sendpacket_mpb_desc(struct vmbus_channel *channel,
+ struct vmbus_packet_mpb_array *desc,
+ u32 desc_size,
+ void *buffer, u32 bufferlen, u64 requestid)
+{
+ int ret;
+ u32 packetlen;
+ u32 packetlen_aligned;
+ struct kvec bufferlist[3];
+ u64 aligned_data = 0;
+ bool signal = false;
+
+ packetlen = desc_size + bufferlen;
+ packetlen_aligned = ALIGN(packetlen, sizeof(u64));
+
+ /* Setup the descriptor */
+ desc->type = VM_PKT_DATA_USING_GPA_DIRECT;
+ desc->flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
+ desc->dataoffset8 = desc_size >> 3; /* in 8-bytes grandularity */
+ desc->length8 = (u16)(packetlen_aligned >> 3);
+ desc->transactionid = requestid;
+ desc->rangecount = 1;
+
+ bufferlist[0].iov_base = desc;
+ bufferlist[0].iov_len = desc_size;
+ bufferlist[1].iov_base = buffer;
+ bufferlist[1].iov_len = bufferlen;
+ bufferlist[2].iov_base = &aligned_data;
+ bufferlist[2].iov_len = (packetlen_aligned - packetlen);
+
+ ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
+
+ if (ret == 0 && signal)
+ vmbus_setevent(channel);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vmbus_sendpacket_mpb_desc);
+
+/*
+ * vmbus_sendpacket_multipagebuffer - Send a multi-page buffer packet
+ * using a GPADL Direct packet type.
+ */
+int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel,
+ struct hv_multipage_buffer *multi_pagebuffer,
+ void *buffer, u32 bufferlen, u64 requestid)
+{
+ int ret;
+ struct vmbus_channel_packet_multipage_buffer desc;
+ u32 descsize;
+ u32 packetlen;
+ u32 packetlen_aligned;
+ struct kvec bufferlist[3];
+ u64 aligned_data = 0;
+ bool signal = false;
+ u32 pfncount = NUM_PAGES_SPANNED(multi_pagebuffer->offset,
+ multi_pagebuffer->len);
+
+ if (pfncount > MAX_MULTIPAGE_BUFFER_COUNT)
+ return -EINVAL;
+
+ /*
+ * Adjust the size down since vmbus_channel_packet_multipage_buffer is
+ * the largest size we support
+ */
+ descsize = sizeof(struct vmbus_channel_packet_multipage_buffer) -
+ ((MAX_MULTIPAGE_BUFFER_COUNT - pfncount) *
+ sizeof(u64));
+ packetlen = descsize + bufferlen;
+ packetlen_aligned = ALIGN(packetlen, sizeof(u64));
+
+
+ /* Setup the descriptor */
+ desc.type = VM_PKT_DATA_USING_GPA_DIRECT;
+ desc.flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
+ desc.dataoffset8 = descsize >> 3; /* in 8-bytes grandularity */
+ desc.length8 = (u16)(packetlen_aligned >> 3);
+ desc.transactionid = requestid;
+ desc.rangecount = 1;
+
+ desc.range.len = multi_pagebuffer->len;
+ desc.range.offset = multi_pagebuffer->offset;
+
+ memcpy(desc.range.pfn_array, multi_pagebuffer->pfn_array,
+ pfncount * sizeof(u64));
+
+ bufferlist[0].iov_base = &desc;
+ bufferlist[0].iov_len = descsize;
+ bufferlist[1].iov_base = buffer;
+ bufferlist[1].iov_len = bufferlen;
+ bufferlist[2].iov_base = &aligned_data;
+ bufferlist[2].iov_len = (packetlen_aligned - packetlen);
+
+ ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
+
+ if (ret == 0 && signal)
+ vmbus_setevent(channel);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vmbus_sendpacket_multipagebuffer);
+
+/**
+ * vmbus_recvpacket() - Retrieve the user packet on the specified channel
+ * @channel: Pointer to vmbus_channel structure.
+ * @buffer: Pointer to the buffer you want to receive the data into.
+ * @bufferlen: Maximum size of what the the buffer will hold
+ * @buffer_actual_len: The actual size of the data after it was received
+ * @requestid: Identifier of the request
+ *
+ * Receives directly from the hyper-v vmbus and puts the data it received
+ * into Buffer. This will receive the data unparsed from hyper-v.
+ *
+ * Mainly used by Hyper-V drivers.
+ */
+int vmbus_recvpacket(struct vmbus_channel *channel, void *buffer,
+ u32 bufferlen, u32 *buffer_actual_len, u64 *requestid)
+{
+ struct vmpacket_descriptor desc;
+ u32 packetlen;
+ u32 userlen;
+ int ret;
+ bool signal = false;
+
+ *buffer_actual_len = 0;
+ *requestid = 0;
+
+
+ ret = hv_ringbuffer_peek(&channel->inbound, &desc,
+ sizeof(struct vmpacket_descriptor));
+ if (ret != 0)
+ return 0;
+
+ packetlen = desc.len8 << 3;
+ userlen = packetlen - (desc.offset8 << 3);
+
+ *buffer_actual_len = userlen;
+
+ if (userlen > bufferlen) {
+
+ pr_err("Buffer too small - got %d needs %d\n",
+ bufferlen, userlen);
+ return -ETOOSMALL;
+ }
+
+ *requestid = desc.trans_id;
+
+ /* Copy over the packet to the user buffer */
+ ret = hv_ringbuffer_read(&channel->inbound, buffer, userlen,
+ (desc.offset8 << 3), &signal);
+
+ if (signal)
+ vmbus_setevent(channel);
+
+ return 0;
+}
+EXPORT_SYMBOL(vmbus_recvpacket);
+
+/*
+ * vmbus_recvpacket_raw - Retrieve the raw packet on the specified channel
+ */
+int vmbus_recvpacket_raw(struct vmbus_channel *channel, void *buffer,
+ u32 bufferlen, u32 *buffer_actual_len,
+ u64 *requestid)
+{
+ struct vmpacket_descriptor desc;
+ u32 packetlen;
+ int ret;
+ bool signal = false;
+
+ *buffer_actual_len = 0;
+ *requestid = 0;
+
+
+ ret = hv_ringbuffer_peek(&channel->inbound, &desc,
+ sizeof(struct vmpacket_descriptor));
+ if (ret != 0)
+ return 0;
+
+
+ packetlen = desc.len8 << 3;
+
+ *buffer_actual_len = packetlen;
+
+ if (packetlen > bufferlen)
+ return -ENOBUFS;
+
+ *requestid = desc.trans_id;
+
+ /* Copy over the entire packet to the user buffer */
+ ret = hv_ringbuffer_read(&channel->inbound, buffer, packetlen, 0,
+ &signal);
+
+ if (signal)
+ vmbus_setevent(channel);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vmbus_recvpacket_raw);
diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
new file mode 100644
index 000000000..0eeb1b3bc
--- /dev/null
+++ b/drivers/hv/channel_mgmt.c
@@ -0,0 +1,862 @@
+/*
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ * Haiyang Zhang <haiyangz@microsoft.com>
+ * Hank Janssen <hjanssen@microsoft.com>
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/completion.h>
+#include <linux/hyperv.h>
+
+#include "hyperv_vmbus.h"
+
+/**
+ * vmbus_prep_negotiate_resp() - Create default response for Hyper-V Negotiate message
+ * @icmsghdrp: Pointer to msg header structure
+ * @icmsg_negotiate: Pointer to negotiate message structure
+ * @buf: Raw buffer channel data
+ *
+ * @icmsghdrp is of type &struct icmsg_hdr.
+ * @negop is of type &struct icmsg_negotiate.
+ * Set up and fill in default negotiate response message.
+ *
+ * The fw_version specifies the framework version that
+ * we can support and srv_version specifies the service
+ * version we can support.
+ *
+ * Mainly used by Hyper-V drivers.
+ */
+bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp,
+ struct icmsg_negotiate *negop, u8 *buf,
+ int fw_version, int srv_version)
+{
+ int icframe_major, icframe_minor;
+ int icmsg_major, icmsg_minor;
+ int fw_major, fw_minor;
+ int srv_major, srv_minor;
+ int i;
+ bool found_match = false;
+
+ icmsghdrp->icmsgsize = 0x10;
+ fw_major = (fw_version >> 16);
+ fw_minor = (fw_version & 0xFFFF);
+
+ srv_major = (srv_version >> 16);
+ srv_minor = (srv_version & 0xFFFF);
+
+ negop = (struct icmsg_negotiate *)&buf[
+ sizeof(struct vmbuspipe_hdr) +
+ sizeof(struct icmsg_hdr)];
+
+ icframe_major = negop->icframe_vercnt;
+ icframe_minor = 0;
+
+ icmsg_major = negop->icmsg_vercnt;
+ icmsg_minor = 0;
+
+ /*
+ * Select the framework version number we will
+ * support.
+ */
+
+ for (i = 0; i < negop->icframe_vercnt; i++) {
+ if ((negop->icversion_data[i].major == fw_major) &&
+ (negop->icversion_data[i].minor == fw_minor)) {
+ icframe_major = negop->icversion_data[i].major;
+ icframe_minor = negop->icversion_data[i].minor;
+ found_match = true;
+ }
+ }
+
+ if (!found_match)
+ goto fw_error;
+
+ found_match = false;
+
+ for (i = negop->icframe_vercnt;
+ (i < negop->icframe_vercnt + negop->icmsg_vercnt); i++) {
+ if ((negop->icversion_data[i].major == srv_major) &&
+ (negop->icversion_data[i].minor == srv_minor)) {
+ icmsg_major = negop->icversion_data[i].major;
+ icmsg_minor = negop->icversion_data[i].minor;
+ found_match = true;
+ }
+ }
+
+ /*
+ * Respond with the framework and service
+ * version numbers we can support.
+ */
+
+fw_error:
+ if (!found_match) {
+ negop->icframe_vercnt = 0;
+ negop->icmsg_vercnt = 0;
+ } else {
+ negop->icframe_vercnt = 1;
+ negop->icmsg_vercnt = 1;
+ }
+
+ negop->icversion_data[0].major = icframe_major;
+ negop->icversion_data[0].minor = icframe_minor;
+ negop->icversion_data[1].major = icmsg_major;
+ negop->icversion_data[1].minor = icmsg_minor;
+ return found_match;
+}
+
+EXPORT_SYMBOL_GPL(vmbus_prep_negotiate_resp);
+
+/*
+ * alloc_channel - Allocate and initialize a vmbus channel object
+ */
+static struct vmbus_channel *alloc_channel(void)
+{
+ static atomic_t chan_num = ATOMIC_INIT(0);
+ struct vmbus_channel *channel;
+
+ channel = kzalloc(sizeof(*channel), GFP_ATOMIC);
+ if (!channel)
+ return NULL;
+
+ channel->id = atomic_inc_return(&chan_num);
+ spin_lock_init(&channel->inbound_lock);
+ spin_lock_init(&channel->lock);
+
+ INIT_LIST_HEAD(&channel->sc_list);
+ INIT_LIST_HEAD(&channel->percpu_list);
+
+ return channel;
+}
+
+/*
+ * free_channel - Release the resources used by the vmbus channel object
+ */
+static void free_channel(struct vmbus_channel *channel)
+{
+ kfree(channel);
+}
+
+static void percpu_channel_enq(void *arg)
+{
+ struct vmbus_channel *channel = arg;
+ int cpu = smp_processor_id();
+
+ list_add_tail(&channel->percpu_list, &hv_context.percpu_list[cpu]);
+}
+
+static void percpu_channel_deq(void *arg)
+{
+ struct vmbus_channel *channel = arg;
+
+ list_del(&channel->percpu_list);
+}
+
+
+void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
+{
+ struct vmbus_channel_relid_released msg;
+ unsigned long flags;
+ struct vmbus_channel *primary_channel;
+
+ memset(&msg, 0, sizeof(struct vmbus_channel_relid_released));
+ msg.child_relid = relid;
+ msg.header.msgtype = CHANNELMSG_RELID_RELEASED;
+ vmbus_post_msg(&msg, sizeof(struct vmbus_channel_relid_released));
+
+ if (channel == NULL)
+ return;
+
+ if (channel->target_cpu != get_cpu()) {
+ put_cpu();
+ smp_call_function_single(channel->target_cpu,
+ percpu_channel_deq, channel, true);
+ } else {
+ percpu_channel_deq(channel);
+ put_cpu();
+ }
+
+ if (channel->primary_channel == NULL) {
+ spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
+ list_del(&channel->listentry);
+ spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
+ } else {
+ primary_channel = channel->primary_channel;
+ spin_lock_irqsave(&primary_channel->lock, flags);
+ list_del(&channel->sc_list);
+ spin_unlock_irqrestore(&primary_channel->lock, flags);
+ }
+ free_channel(channel);
+}
+
+void vmbus_free_channels(void)
+{
+ struct vmbus_channel *channel;
+
+ list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
+ vmbus_device_unregister(channel->device_obj);
+ free_channel(channel);
+ }
+}
+
+/*
+ * vmbus_process_offer - Process the offer by creating a channel/device
+ * associated with this offer
+ */
+static void vmbus_process_offer(struct vmbus_channel *newchannel)
+{
+ struct vmbus_channel *channel;
+ bool fnew = true;
+ bool enq = false;
+ unsigned long flags;
+
+ /* Make sure this is a new offer */
+ spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
+
+ list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
+ if (!uuid_le_cmp(channel->offermsg.offer.if_type,
+ newchannel->offermsg.offer.if_type) &&
+ !uuid_le_cmp(channel->offermsg.offer.if_instance,
+ newchannel->offermsg.offer.if_instance)) {
+ fnew = false;
+ break;
+ }
+ }
+
+ if (fnew) {
+ list_add_tail(&newchannel->listentry,
+ &vmbus_connection.chn_list);
+ enq = true;
+ }
+
+ spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
+
+ if (enq) {
+ if (newchannel->target_cpu != get_cpu()) {
+ put_cpu();
+ smp_call_function_single(newchannel->target_cpu,
+ percpu_channel_enq,
+ newchannel, true);
+ } else {
+ percpu_channel_enq(newchannel);
+ put_cpu();
+ }
+ }
+ if (!fnew) {
+ /*
+ * Check to see if this is a sub-channel.
+ */
+ if (newchannel->offermsg.offer.sub_channel_index != 0) {
+ /*
+ * Process the sub-channel.
+ */
+ newchannel->primary_channel = channel;
+ spin_lock_irqsave(&channel->lock, flags);
+ list_add_tail(&newchannel->sc_list, &channel->sc_list);
+ spin_unlock_irqrestore(&channel->lock, flags);
+
+ if (newchannel->target_cpu != get_cpu()) {
+ put_cpu();
+ smp_call_function_single(newchannel->target_cpu,
+ percpu_channel_enq,
+ newchannel, true);
+ } else {
+ percpu_channel_enq(newchannel);
+ put_cpu();
+ }
+
+ newchannel->state = CHANNEL_OPEN_STATE;
+ channel->num_sc++;
+ if (channel->sc_creation_callback != NULL)
+ channel->sc_creation_callback(newchannel);
+
+ return;
+ }
+
+ goto err_free_chan;
+ }
+
+ /*
+ * This state is used to indicate a successful open
+ * so that when we do close the channel normally, we
+ * can cleanup properly
+ */
+ newchannel->state = CHANNEL_OPEN_STATE;
+
+ /*
+ * Start the process of binding this offer to the driver
+ * We need to set the DeviceObject field before calling
+ * vmbus_child_dev_add()
+ */
+ newchannel->device_obj = vmbus_device_create(
+ &newchannel->offermsg.offer.if_type,
+ &newchannel->offermsg.offer.if_instance,
+ newchannel);
+ if (!newchannel->device_obj)
+ goto err_deq_chan;
+
+ /*
+ * Add the new device to the bus. This will kick off device-driver
+ * binding which eventually invokes the device driver's AddDevice()
+ * method.
+ */
+ if (vmbus_device_register(newchannel->device_obj) != 0) {
+ pr_err("unable to add child device object (relid %d)\n",
+ newchannel->offermsg.child_relid);
+ kfree(newchannel->device_obj);
+ goto err_deq_chan;
+ }
+ return;
+
+err_deq_chan:
+ spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
+ list_del(&newchannel->listentry);
+ spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
+
+ if (newchannel->target_cpu != get_cpu()) {
+ put_cpu();
+ smp_call_function_single(newchannel->target_cpu,
+ percpu_channel_deq, newchannel, true);
+ } else {
+ percpu_channel_deq(newchannel);
+ put_cpu();
+ }
+
+err_free_chan:
+ free_channel(newchannel);
+}
+
+enum {
+ IDE = 0,
+ SCSI,
+ NIC,
+ MAX_PERF_CHN,
+};
+
+/*
+ * This is an array of device_ids (device types) that are performance critical.
+ * We attempt to distribute the interrupt load for these devices across
+ * all available CPUs.
+ */
+static const struct hv_vmbus_device_id hp_devs[] = {
+ /* IDE */
+ { HV_IDE_GUID, },
+ /* Storage - SCSI */
+ { HV_SCSI_GUID, },
+ /* Network */
+ { HV_NIC_GUID, },
+ /* NetworkDirect Guest RDMA */
+ { HV_ND_GUID, },
+};
+
+
+/*
+ * We use this state to statically distribute the channel interrupt load.
+ */
+static u32 next_vp;
+
+/*
+ * Starting with Win8, we can statically distribute the incoming
+ * channel interrupt load by binding a channel to VCPU. We
+ * implement here a simple round robin scheme for distributing
+ * the interrupt load.
+ * We will bind channels that are not performance critical to cpu 0 and
+ * performance critical channels (IDE, SCSI and Network) will be uniformly
+ * distributed across all available CPUs.
+ */
+static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_guid)
+{
+ u32 cur_cpu;
+ int i;
+ bool perf_chn = false;
+ u32 max_cpus = num_online_cpus();
+
+ for (i = IDE; i < MAX_PERF_CHN; i++) {
+ if (!memcmp(type_guid->b, hp_devs[i].guid,
+ sizeof(uuid_le))) {
+ perf_chn = true;
+ break;
+ }
+ }
+ if ((vmbus_proto_version == VERSION_WS2008) ||
+ (vmbus_proto_version == VERSION_WIN7) || (!perf_chn)) {
+ /*
+ * Prior to win8, all channel interrupts are
+ * delivered on cpu 0.
+ * Also if the channel is not a performance critical
+ * channel, bind it to cpu 0.
+ */
+ channel->target_cpu = 0;
+ channel->target_vp = 0;
+ return;
+ }
+ cur_cpu = (++next_vp % max_cpus);
+ channel->target_cpu = cur_cpu;
+ channel->target_vp = hv_context.vp_index[cur_cpu];
+}
+
+/*
+ * vmbus_onoffer - Handler for channel offers from vmbus in parent partition.
+ *
+ */
+static void vmbus_onoffer(struct vmbus_channel_message_header *hdr)
+{
+ struct vmbus_channel_offer_channel *offer;
+ struct vmbus_channel *newchannel;
+
+ offer = (struct vmbus_channel_offer_channel *)hdr;
+
+ /* Allocate the channel object and save this offer. */
+ newchannel = alloc_channel();
+ if (!newchannel) {
+ pr_err("Unable to allocate channel object\n");
+ return;
+ }
+
+ /*
+ * By default we setup state to enable batched
+ * reading. A specific service can choose to
+ * disable this prior to opening the channel.
+ */
+ newchannel->batched_reading = true;
+
+ /*
+ * Setup state for signalling the host.
+ */
+ newchannel->sig_event = (struct hv_input_signal_event *)
+ (ALIGN((unsigned long)
+ &newchannel->sig_buf,
+ HV_HYPERCALL_PARAM_ALIGN));
+
+ newchannel->sig_event->connectionid.asu32 = 0;
+ newchannel->sig_event->connectionid.u.id = VMBUS_EVENT_CONNECTION_ID;
+ newchannel->sig_event->flag_number = 0;
+ newchannel->sig_event->rsvdz = 0;
+
+ if (vmbus_proto_version != VERSION_WS2008) {
+ newchannel->is_dedicated_interrupt =
+ (offer->is_dedicated_interrupt != 0);
+ newchannel->sig_event->connectionid.u.id =
+ offer->connection_id;
+ }
+
+ init_vp_index(newchannel, &offer->offer.if_type);
+
+ memcpy(&newchannel->offermsg, offer,
+ sizeof(struct vmbus_channel_offer_channel));
+ newchannel->monitor_grp = (u8)offer->monitorid / 32;
+ newchannel->monitor_bit = (u8)offer->monitorid % 32;
+
+ vmbus_process_offer(newchannel);
+}
+
+/*
+ * vmbus_onoffer_rescind - Rescind offer handler.
+ *
+ * We queue a work item to process this offer synchronously
+ */
+static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
+{
+ struct vmbus_channel_rescind_offer *rescind;
+ struct vmbus_channel *channel;
+ unsigned long flags;
+ struct device *dev;
+
+ rescind = (struct vmbus_channel_rescind_offer *)hdr;
+ channel = relid2channel(rescind->child_relid);
+
+ if (channel == NULL) {
+ hv_process_channel_removal(NULL, rescind->child_relid);
+ return;
+ }
+
+ spin_lock_irqsave(&channel->lock, flags);
+ channel->rescind = true;
+ spin_unlock_irqrestore(&channel->lock, flags);
+
+ if (channel->device_obj) {
+ /*
+ * We will have to unregister this device from the
+ * driver core.
+ */
+ dev = get_device(&channel->device_obj->device);
+ if (dev) {
+ vmbus_device_unregister(channel->device_obj);
+ put_device(dev);
+ }
+ } else {
+ hv_process_channel_removal(channel,
+ channel->offermsg.child_relid);
+ }
+}
+
+/*
+ * vmbus_onoffers_delivered -
+ * This is invoked when all offers have been delivered.
+ *
+ * Nothing to do here.
+ */
+static void vmbus_onoffers_delivered(
+ struct vmbus_channel_message_header *hdr)
+{
+}
+
+/*
+ * vmbus_onopen_result - Open result handler.
+ *
+ * This is invoked when we received a response to our channel open request.
+ * Find the matching request, copy the response and signal the requesting
+ * thread.
+ */
+static void vmbus_onopen_result(struct vmbus_channel_message_header *hdr)
+{
+ struct vmbus_channel_open_result *result;
+ struct vmbus_channel_msginfo *msginfo;
+ struct vmbus_channel_message_header *requestheader;
+ struct vmbus_channel_open_channel *openmsg;
+ unsigned long flags;
+
+ result = (struct vmbus_channel_open_result *)hdr;
+
+ /*
+ * Find the open msg, copy the result and signal/unblock the wait event
+ */
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+
+ list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
+ msglistentry) {
+ requestheader =
+ (struct vmbus_channel_message_header *)msginfo->msg;
+
+ if (requestheader->msgtype == CHANNELMSG_OPENCHANNEL) {
+ openmsg =
+ (struct vmbus_channel_open_channel *)msginfo->msg;
+ if (openmsg->child_relid == result->child_relid &&
+ openmsg->openid == result->openid) {
+ memcpy(&msginfo->response.open_result,
+ result,
+ sizeof(
+ struct vmbus_channel_open_result));
+ complete(&msginfo->waitevent);
+ break;
+ }
+ }
+ }
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+}
+
+/*
+ * vmbus_ongpadl_created - GPADL created handler.
+ *
+ * This is invoked when we received a response to our gpadl create request.
+ * Find the matching request, copy the response and signal the requesting
+ * thread.
+ */
+static void vmbus_ongpadl_created(struct vmbus_channel_message_header *hdr)
+{
+ struct vmbus_channel_gpadl_created *gpadlcreated;
+ struct vmbus_channel_msginfo *msginfo;
+ struct vmbus_channel_message_header *requestheader;
+ struct vmbus_channel_gpadl_header *gpadlheader;
+ unsigned long flags;
+
+ gpadlcreated = (struct vmbus_channel_gpadl_created *)hdr;
+
+ /*
+ * Find the establish msg, copy the result and signal/unblock the wait
+ * event
+ */
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+
+ list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
+ msglistentry) {
+ requestheader =
+ (struct vmbus_channel_message_header *)msginfo->msg;
+
+ if (requestheader->msgtype == CHANNELMSG_GPADL_HEADER) {
+ gpadlheader =
+ (struct vmbus_channel_gpadl_header *)requestheader;
+
+ if ((gpadlcreated->child_relid ==
+ gpadlheader->child_relid) &&
+ (gpadlcreated->gpadl == gpadlheader->gpadl)) {
+ memcpy(&msginfo->response.gpadl_created,
+ gpadlcreated,
+ sizeof(
+ struct vmbus_channel_gpadl_created));
+ complete(&msginfo->waitevent);
+ break;
+ }
+ }
+ }
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+}
+
+/*
+ * vmbus_ongpadl_torndown - GPADL torndown handler.
+ *
+ * This is invoked when we received a response to our gpadl teardown request.
+ * Find the matching request, copy the response and signal the requesting
+ * thread.
+ */
+static void vmbus_ongpadl_torndown(
+ struct vmbus_channel_message_header *hdr)
+{
+ struct vmbus_channel_gpadl_torndown *gpadl_torndown;
+ struct vmbus_channel_msginfo *msginfo;
+ struct vmbus_channel_message_header *requestheader;
+ struct vmbus_channel_gpadl_teardown *gpadl_teardown;
+ unsigned long flags;
+
+ gpadl_torndown = (struct vmbus_channel_gpadl_torndown *)hdr;
+
+ /*
+ * Find the open msg, copy the result and signal/unblock the wait event
+ */
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+
+ list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
+ msglistentry) {
+ requestheader =
+ (struct vmbus_channel_message_header *)msginfo->msg;
+
+ if (requestheader->msgtype == CHANNELMSG_GPADL_TEARDOWN) {
+ gpadl_teardown =
+ (struct vmbus_channel_gpadl_teardown *)requestheader;
+
+ if (gpadl_torndown->gpadl == gpadl_teardown->gpadl) {
+ memcpy(&msginfo->response.gpadl_torndown,
+ gpadl_torndown,
+ sizeof(
+ struct vmbus_channel_gpadl_torndown));
+ complete(&msginfo->waitevent);
+ break;
+ }
+ }
+ }
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+}
+
+/*
+ * vmbus_onversion_response - Version response handler
+ *
+ * This is invoked when we received a response to our initiate contact request.
+ * Find the matching request, copy the response and signal the requesting
+ * thread.
+ */
+static void vmbus_onversion_response(
+ struct vmbus_channel_message_header *hdr)
+{
+ struct vmbus_channel_msginfo *msginfo;
+ struct vmbus_channel_message_header *requestheader;
+ struct vmbus_channel_version_response *version_response;
+ unsigned long flags;
+
+ version_response = (struct vmbus_channel_version_response *)hdr;
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+
+ list_for_each_entry(msginfo, &vmbus_connection.chn_msg_list,
+ msglistentry) {
+ requestheader =
+ (struct vmbus_channel_message_header *)msginfo->msg;
+
+ if (requestheader->msgtype ==
+ CHANNELMSG_INITIATE_CONTACT) {
+ memcpy(&msginfo->response.version_response,
+ version_response,
+ sizeof(struct vmbus_channel_version_response));
+ complete(&msginfo->waitevent);
+ }
+ }
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+}
+
+/* Channel message dispatch table */
+struct vmbus_channel_message_table_entry
+ channel_message_table[CHANNELMSG_COUNT] = {
+ {CHANNELMSG_INVALID, 0, NULL},
+ {CHANNELMSG_OFFERCHANNEL, 0, vmbus_onoffer},
+ {CHANNELMSG_RESCIND_CHANNELOFFER, 0, vmbus_onoffer_rescind},
+ {CHANNELMSG_REQUESTOFFERS, 0, NULL},
+ {CHANNELMSG_ALLOFFERS_DELIVERED, 1, vmbus_onoffers_delivered},
+ {CHANNELMSG_OPENCHANNEL, 0, NULL},
+ {CHANNELMSG_OPENCHANNEL_RESULT, 1, vmbus_onopen_result},
+ {CHANNELMSG_CLOSECHANNEL, 0, NULL},
+ {CHANNELMSG_GPADL_HEADER, 0, NULL},
+ {CHANNELMSG_GPADL_BODY, 0, NULL},
+ {CHANNELMSG_GPADL_CREATED, 1, vmbus_ongpadl_created},
+ {CHANNELMSG_GPADL_TEARDOWN, 0, NULL},
+ {CHANNELMSG_GPADL_TORNDOWN, 1, vmbus_ongpadl_torndown},
+ {CHANNELMSG_RELID_RELEASED, 0, NULL},
+ {CHANNELMSG_INITIATE_CONTACT, 0, NULL},
+ {CHANNELMSG_VERSION_RESPONSE, 1, vmbus_onversion_response},
+ {CHANNELMSG_UNLOAD, 0, NULL},
+};
+
+/*
+ * vmbus_onmessage - Handler for channel protocol messages.
+ *
+ * This is invoked in the vmbus worker thread context.
+ */
+void vmbus_onmessage(void *context)
+{
+ struct hv_message *msg = context;
+ struct vmbus_channel_message_header *hdr;
+ int size;
+
+ hdr = (struct vmbus_channel_message_header *)msg->u.payload;
+ size = msg->header.payload_size;
+
+ if (hdr->msgtype >= CHANNELMSG_COUNT) {
+ pr_err("Received invalid channel message type %d size %d\n",
+ hdr->msgtype, size);
+ print_hex_dump_bytes("", DUMP_PREFIX_NONE,
+ (unsigned char *)msg->u.payload, size);
+ return;
+ }
+
+ if (channel_message_table[hdr->msgtype].message_handler)
+ channel_message_table[hdr->msgtype].message_handler(hdr);
+ else
+ pr_err("Unhandled channel message type %d\n", hdr->msgtype);
+}
+
+/*
+ * vmbus_request_offers - Send a request to get all our pending offers.
+ */
+int vmbus_request_offers(void)
+{
+ struct vmbus_channel_message_header *msg;
+ struct vmbus_channel_msginfo *msginfo;
+ int ret;
+
+ msginfo = kmalloc(sizeof(*msginfo) +
+ sizeof(struct vmbus_channel_message_header),
+ GFP_KERNEL);
+ if (!msginfo)
+ return -ENOMEM;
+
+ msg = (struct vmbus_channel_message_header *)msginfo->msg;
+
+ msg->msgtype = CHANNELMSG_REQUESTOFFERS;
+
+
+ ret = vmbus_post_msg(msg,
+ sizeof(struct vmbus_channel_message_header));
+ if (ret != 0) {
+ pr_err("Unable to request offers - %d\n", ret);
+
+ goto cleanup;
+ }
+
+cleanup:
+ kfree(msginfo);
+
+ return ret;
+}
+
+/*
+ * Retrieve the (sub) channel on which to send an outgoing request.
+ * When a primary channel has multiple sub-channels, we try to
+ * distribute the load equally amongst all available channels.
+ */
+struct vmbus_channel *vmbus_get_outgoing_channel(struct vmbus_channel *primary)
+{
+ struct list_head *cur, *tmp;
+ int cur_cpu;
+ struct vmbus_channel *cur_channel;
+ struct vmbus_channel *outgoing_channel = primary;
+ int next_channel;
+ int i = 1;
+
+ if (list_empty(&primary->sc_list))
+ return outgoing_channel;
+
+ next_channel = primary->next_oc++;
+
+ if (next_channel > (primary->num_sc)) {
+ primary->next_oc = 0;
+ return outgoing_channel;
+ }
+
+ cur_cpu = hv_context.vp_index[get_cpu()];
+ put_cpu();
+ list_for_each_safe(cur, tmp, &primary->sc_list) {
+ cur_channel = list_entry(cur, struct vmbus_channel, sc_list);
+ if (cur_channel->state != CHANNEL_OPENED_STATE)
+ continue;
+
+ if (cur_channel->target_vp == cur_cpu)
+ return cur_channel;
+
+ if (i == next_channel)
+ return cur_channel;
+
+ i++;
+ }
+
+ return outgoing_channel;
+}
+EXPORT_SYMBOL_GPL(vmbus_get_outgoing_channel);
+
+static void invoke_sc_cb(struct vmbus_channel *primary_channel)
+{
+ struct list_head *cur, *tmp;
+ struct vmbus_channel *cur_channel;
+
+ if (primary_channel->sc_creation_callback == NULL)
+ return;
+
+ list_for_each_safe(cur, tmp, &primary_channel->sc_list) {
+ cur_channel = list_entry(cur, struct vmbus_channel, sc_list);
+
+ primary_channel->sc_creation_callback(cur_channel);
+ }
+}
+
+void vmbus_set_sc_create_callback(struct vmbus_channel *primary_channel,
+ void (*sc_cr_cb)(struct vmbus_channel *new_sc))
+{
+ primary_channel->sc_creation_callback = sc_cr_cb;
+}
+EXPORT_SYMBOL_GPL(vmbus_set_sc_create_callback);
+
+bool vmbus_are_subchannels_present(struct vmbus_channel *primary)
+{
+ bool ret;
+
+ ret = !list_empty(&primary->sc_list);
+
+ if (ret) {
+ /*
+ * Invoke the callback on sub-channel creation.
+ * This will present a uniform interface to the
+ * clients.
+ */
+ invoke_sc_cb(primary);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(vmbus_are_subchannels_present);
diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
new file mode 100644
index 000000000..b27220a42
--- /dev/null
+++ b/drivers/hv/connection.c
@@ -0,0 +1,480 @@
+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ * Haiyang Zhang <haiyangz@microsoft.com>
+ * Hank Janssen <hjanssen@microsoft.com>
+ *
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/delay.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/hyperv.h>
+#include <linux/export.h>
+#include <asm/hyperv.h>
+#include "hyperv_vmbus.h"
+
+
+struct vmbus_connection vmbus_connection = {
+ .conn_state = DISCONNECTED,
+ .next_gpadl_handle = ATOMIC_INIT(0xE1E10),
+};
+
+/*
+ * Negotiated protocol version with the host.
+ */
+__u32 vmbus_proto_version;
+EXPORT_SYMBOL_GPL(vmbus_proto_version);
+
+static __u32 vmbus_get_next_version(__u32 current_version)
+{
+ switch (current_version) {
+ case (VERSION_WIN7):
+ return VERSION_WS2008;
+
+ case (VERSION_WIN8):
+ return VERSION_WIN7;
+
+ case (VERSION_WIN8_1):
+ return VERSION_WIN8;
+
+ case (VERSION_WS2008):
+ default:
+ return VERSION_INVAL;
+ }
+}
+
+static int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo,
+ __u32 version)
+{
+ int ret = 0;
+ struct vmbus_channel_initiate_contact *msg;
+ unsigned long flags;
+
+ init_completion(&msginfo->waitevent);
+
+ msg = (struct vmbus_channel_initiate_contact *)msginfo->msg;
+
+ msg->header.msgtype = CHANNELMSG_INITIATE_CONTACT;
+ msg->vmbus_version_requested = version;
+ msg->interrupt_page = virt_to_phys(vmbus_connection.int_page);
+ msg->monitor_page1 = virt_to_phys(vmbus_connection.monitor_pages[0]);
+ msg->monitor_page2 = virt_to_phys(vmbus_connection.monitor_pages[1]);
+ if (version == VERSION_WIN8_1) {
+ msg->target_vcpu = hv_context.vp_index[get_cpu()];
+ put_cpu();
+ }
+
+ /*
+ * Add to list before we send the request since we may
+ * receive the response before returning from this routine
+ */
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+ list_add_tail(&msginfo->msglistentry,
+ &vmbus_connection.chn_msg_list);
+
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+
+ ret = vmbus_post_msg(msg,
+ sizeof(struct vmbus_channel_initiate_contact));
+ if (ret != 0) {
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+ list_del(&msginfo->msglistentry);
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock,
+ flags);
+ return ret;
+ }
+
+ /* Wait for the connection response */
+ wait_for_completion(&msginfo->waitevent);
+
+ spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
+ list_del(&msginfo->msglistentry);
+ spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
+
+ /* Check if successful */
+ if (msginfo->response.version_response.version_supported) {
+ vmbus_connection.conn_state = CONNECTED;
+ } else {
+ return -ECONNREFUSED;
+ }
+
+ return ret;
+}
+
+/*
+ * vmbus_connect - Sends a connect request on the partition service connection
+ */
+int vmbus_connect(void)
+{
+ int ret = 0;
+ struct vmbus_channel_msginfo *msginfo = NULL;
+ __u32 version;
+
+ /* Initialize the vmbus connection */
+ vmbus_connection.conn_state = CONNECTING;
+ vmbus_connection.work_queue = create_workqueue("hv_vmbus_con");
+ if (!vmbus_connection.work_queue) {
+ ret = -ENOMEM;
+ goto cleanup;
+ }
+
+ INIT_LIST_HEAD(&vmbus_connection.chn_msg_list);
+ spin_lock_init(&vmbus_connection.channelmsg_lock);
+
+ INIT_LIST_HEAD(&vmbus_connection.chn_list);
+ spin_lock_init(&vmbus_connection.channel_lock);
+
+ /*
+ * Setup the vmbus event connection for channel interrupt
+ * abstraction stuff
+ */
+ vmbus_connection.int_page =
+ (void *)__get_free_pages(GFP_KERNEL|__GFP_ZERO, 0);
+ if (vmbus_connection.int_page == NULL) {
+ ret = -ENOMEM;
+ goto cleanup;
+ }
+
+ vmbus_connection.recv_int_page = vmbus_connection.int_page;
+ vmbus_connection.send_int_page =
+ (void *)((unsigned long)vmbus_connection.int_page +
+ (PAGE_SIZE >> 1));
+
+ /*
+ * Setup the monitor notification facility. The 1st page for
+ * parent->child and the 2nd page for child->parent
+ */
+ vmbus_connection.monitor_pages[0] = (void *)__get_free_pages((GFP_KERNEL|__GFP_ZERO), 0);
+ vmbus_connection.monitor_pages[1] = (void *)__get_free_pages((GFP_KERNEL|__GFP_ZERO), 0);
+ if ((vmbus_connection.monitor_pages[0] == NULL) ||
+ (vmbus_connection.monitor_pages[1] == NULL)) {
+ ret = -ENOMEM;
+ goto cleanup;
+ }
+
+ msginfo = kzalloc(sizeof(*msginfo) +
+ sizeof(struct vmbus_channel_initiate_contact),
+ GFP_KERNEL);
+ if (msginfo == NULL) {
+ ret = -ENOMEM;
+ goto cleanup;
+ }
+
+ /*
+ * Negotiate a compatible VMBUS version number with the
+ * host. We start with the highest number we can support
+ * and work our way down until we negotiate a compatible
+ * version.
+ */
+
+ version = VERSION_CURRENT;
+
+ do {
+ ret = vmbus_negotiate_version(msginfo, version);
+ if (ret == -ETIMEDOUT)
+ goto cleanup;
+
+ if (vmbus_connection.conn_state == CONNECTED)
+ break;
+
+ version = vmbus_get_next_version(version);
+ } while (version != VERSION_INVAL);
+
+ if (version == VERSION_INVAL)
+ goto cleanup;
+
+ vmbus_proto_version = version;
+ pr_info("Hyper-V Host Build:%d-%d.%d-%d-%d.%d; Vmbus version:%d.%d\n",
+ host_info_eax, host_info_ebx >> 16,
+ host_info_ebx & 0xFFFF, host_info_ecx,
+ host_info_edx >> 24, host_info_edx & 0xFFFFFF,
+ version >> 16, version & 0xFFFF);
+
+ kfree(msginfo);
+ return 0;
+
+cleanup:
+ pr_err("Unable to connect to host\n");
+
+ vmbus_connection.conn_state = DISCONNECTED;
+ vmbus_disconnect();
+
+ kfree(msginfo);
+
+ return ret;
+}
+
+void vmbus_disconnect(void)
+{
+ if (vmbus_connection.work_queue) {
+ drain_workqueue(vmbus_connection.work_queue);
+ destroy_workqueue(vmbus_connection.work_queue);
+ }
+
+ if (vmbus_connection.int_page) {
+ free_pages((unsigned long)vmbus_connection.int_page, 0);
+ vmbus_connection.int_page = NULL;
+ }
+
+ free_pages((unsigned long)vmbus_connection.monitor_pages[0], 0);
+ free_pages((unsigned long)vmbus_connection.monitor_pages[1], 0);
+ vmbus_connection.monitor_pages[0] = NULL;
+ vmbus_connection.monitor_pages[1] = NULL;
+}
+
+/*
+ * Map the given relid to the corresponding channel based on the
+ * per-cpu list of channels that have been affinitized to this CPU.
+ * This will be used in the channel callback path as we can do this
+ * mapping in a lock-free fashion.
+ */
+static struct vmbus_channel *pcpu_relid2channel(u32 relid)
+{
+ struct vmbus_channel *channel;
+ struct vmbus_channel *found_channel = NULL;
+ int cpu = smp_processor_id();
+ struct list_head *pcpu_head = &hv_context.percpu_list[cpu];
+
+ list_for_each_entry(channel, pcpu_head, percpu_list) {
+ if (channel->offermsg.child_relid == relid) {
+ found_channel = channel;
+ break;
+ }
+ }
+
+ return found_channel;
+}
+
+/*
+ * relid2channel - Get the channel object given its
+ * child relative id (ie channel id)
+ */
+struct vmbus_channel *relid2channel(u32 relid)
+{
+ struct vmbus_channel *channel;
+ struct vmbus_channel *found_channel = NULL;
+ unsigned long flags;
+ struct list_head *cur, *tmp;
+ struct vmbus_channel *cur_sc;
+
+ spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
+ list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
+ if (channel->offermsg.child_relid == relid) {
+ found_channel = channel;
+ break;
+ } else if (!list_empty(&channel->sc_list)) {
+ /*
+ * Deal with sub-channels.
+ */
+ list_for_each_safe(cur, tmp, &channel->sc_list) {
+ cur_sc = list_entry(cur, struct vmbus_channel,
+ sc_list);
+ if (cur_sc->offermsg.child_relid == relid) {
+ found_channel = cur_sc;
+ break;
+ }
+ }
+ }
+ }
+ spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
+
+ return found_channel;
+}
+
+/*
+ * process_chn_event - Process a channel event notification
+ */
+static void process_chn_event(u32 relid)
+{
+ struct vmbus_channel *channel;
+ void *arg;
+ bool read_state;
+ u32 bytes_to_read;
+
+ /*
+ * Find the channel based on this relid and invokes the
+ * channel callback to process the event
+ */
+ channel = pcpu_relid2channel(relid);
+
+ if (!channel)
+ return;
+
+ /*
+ * A channel once created is persistent even when there
+ * is no driver handling the device. An unloading driver
+ * sets the onchannel_callback to NULL on the same CPU
+ * as where this interrupt is handled (in an interrupt context).
+ * Thus, checking and invoking the driver specific callback takes
+ * care of orderly unloading of the driver.
+ */
+
+ if (channel->onchannel_callback != NULL) {
+ arg = channel->channel_callback_context;
+ read_state = channel->batched_reading;
+ /*
+ * This callback reads the messages sent by the host.
+ * We can optimize host to guest signaling by ensuring:
+ * 1. While reading the channel, we disable interrupts from
+ * host.
+ * 2. Ensure that we process all posted messages from the host
+ * before returning from this callback.
+ * 3. Once we return, enable signaling from the host. Once this
+ * state is set we check to see if additional packets are
+ * available to read. In this case we repeat the process.
+ */
+
+ do {
+ if (read_state)
+ hv_begin_read(&channel->inbound);
+ channel->onchannel_callback(arg);
+ if (read_state)
+ bytes_to_read = hv_end_read(&channel->inbound);
+ else
+ bytes_to_read = 0;
+ } while (read_state && (bytes_to_read != 0));
+ }
+}
+
+/*
+ * vmbus_on_event - Handler for events
+ */
+void vmbus_on_event(unsigned long data)
+{
+ u32 dword;
+ u32 maxdword;
+ int bit;
+ u32 relid;
+ u32 *recv_int_page = NULL;
+ void *page_addr;
+ int cpu = smp_processor_id();
+ union hv_synic_event_flags *event;
+
+ if ((vmbus_proto_version == VERSION_WS2008) ||
+ (vmbus_proto_version == VERSION_WIN7)) {
+ maxdword = MAX_NUM_CHANNELS_SUPPORTED >> 5;
+ recv_int_page = vmbus_connection.recv_int_page;
+ } else {
+ /*
+ * When the host is win8 and beyond, the event page
+ * can be directly checked to get the id of the channel
+ * that has the interrupt pending.
+ */
+ maxdword = HV_EVENT_FLAGS_DWORD_COUNT;
+ page_addr = hv_context.synic_event_page[cpu];
+ event = (union hv_synic_event_flags *)page_addr +
+ VMBUS_MESSAGE_SINT;
+ recv_int_page = event->flags32;
+ }
+
+
+
+ /* Check events */
+ if (!recv_int_page)
+ return;
+ for (dword = 0; dword < maxdword; dword++) {
+ if (!recv_int_page[dword])
+ continue;
+ for (bit = 0; bit < 32; bit++) {
+ if (sync_test_and_clear_bit(bit,
+ (unsigned long *)&recv_int_page[dword])) {
+ relid = (dword << 5) + bit;
+
+ if (relid == 0)
+ /*
+ * Special case - vmbus
+ * channel protocol msg
+ */
+ continue;
+
+ process_chn_event(relid);
+ }
+ }
+ }
+}
+
+/*
+ * vmbus_post_msg - Send a msg on the vmbus's message connection
+ */
+int vmbus_post_msg(void *buffer, size_t buflen)
+{
+ union hv_connection_id conn_id;
+ int ret = 0;
+ int retries = 0;
+ u32 msec = 1;
+
+ conn_id.asu32 = 0;
+ conn_id.u.id = VMBUS_MESSAGE_CONNECTION_ID;
+
+ /*
+ * hv_post_message() can have transient failures because of
+ * insufficient resources. Retry the operation a couple of
+ * times before giving up.
+ */
+ while (retries < 20) {
+ ret = hv_post_message(conn_id, 1, buffer, buflen);
+
+ switch (ret) {
+ case HV_STATUS_INVALID_CONNECTION_ID:
+ /*
+ * We could get this if we send messages too
+ * frequently.
+ */
+ ret = -EAGAIN;
+ break;
+ case HV_STATUS_INSUFFICIENT_MEMORY:
+ case HV_STATUS_INSUFFICIENT_BUFFERS:
+ ret = -ENOMEM;
+ break;
+ case HV_STATUS_SUCCESS:
+ return ret;
+ default:
+ pr_err("hv_post_msg() failed; error code:%d\n", ret);
+ return -EINVAL;
+ }
+
+ retries++;
+ msleep(msec);
+ if (msec < 2048)
+ msec *= 2;
+ }
+ return ret;
+}
+
+/*
+ * vmbus_set_event - Send an event notification to the parent
+ */
+int vmbus_set_event(struct vmbus_channel *channel)
+{
+ u32 child_relid = channel->offermsg.child_relid;
+
+ if (!channel->is_dedicated_interrupt) {
+ /* Each u32 represents 32 channels */
+ sync_set_bit(child_relid & 31,
+ (unsigned long *)vmbus_connection.send_int_page +
+ (child_relid >> 5));
+ }
+
+ return hv_signal_event(channel->sig_event);
+}
diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
new file mode 100644
index 000000000..d3943bcee
--- /dev/null
+++ b/drivers/hv/hv.c
@@ -0,0 +1,535 @@
+/*
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ * Haiyang Zhang <haiyangz@microsoft.com>
+ * Hank Janssen <hjanssen@microsoft.com>
+ *
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/hyperv.h>
+#include <linux/version.h>
+#include <linux/interrupt.h>
+#include <linux/clockchips.h>
+#include <asm/hyperv.h>
+#include <asm/mshyperv.h>
+#include "hyperv_vmbus.h"
+
+/* The one and only */
+struct hv_context hv_context = {
+ .synic_initialized = false,
+ .hypercall_page = NULL,
+};
+
+#define HV_TIMER_FREQUENCY (10 * 1000 * 1000) /* 100ns period */
+#define HV_MAX_MAX_DELTA_TICKS 0xffffffff
+#define HV_MIN_DELTA_TICKS 1
+
+/*
+ * query_hypervisor_info - Get version info of the windows hypervisor
+ */
+unsigned int host_info_eax;
+unsigned int host_info_ebx;
+unsigned int host_info_ecx;
+unsigned int host_info_edx;
+
+static int query_hypervisor_info(void)
+{
+ unsigned int eax;
+ unsigned int ebx;
+ unsigned int ecx;
+ unsigned int edx;
+ unsigned int max_leaf;
+ unsigned int op;
+
+ /*
+ * Its assumed that this is called after confirming that Viridian
+ * is present. Query id and revision.
+ */
+ eax = 0;
+ ebx = 0;
+ ecx = 0;
+ edx = 0;
+ op = HVCPUID_VENDOR_MAXFUNCTION;
+ cpuid(op, &eax, &ebx, &ecx, &edx);
+
+ max_leaf = eax;
+
+ if (max_leaf >= HVCPUID_VERSION) {
+ eax = 0;
+ ebx = 0;
+ ecx = 0;
+ edx = 0;
+ op = HVCPUID_VERSION;
+ cpuid(op, &eax, &ebx, &ecx, &edx);
+ host_info_eax = eax;
+ host_info_ebx = ebx;
+ host_info_ecx = ecx;
+ host_info_edx = edx;
+ }
+ return max_leaf;
+}
+
+/*
+ * do_hypercall- Invoke the specified hypercall
+ */
+static u64 do_hypercall(u64 control, void *input, void *output)
+{
+#ifdef CONFIG_X86_64
+ u64 hv_status = 0;
+ u64 input_address = (input) ? virt_to_phys(input) : 0;
+ u64 output_address = (output) ? virt_to_phys(output) : 0;
+ void *hypercall_page = hv_context.hypercall_page;
+
+ __asm__ __volatile__("mov %0, %%r8" : : "r" (output_address) : "r8");
+ __asm__ __volatile__("call *%3" : "=a" (hv_status) :
+ "c" (control), "d" (input_address),
+ "m" (hypercall_page));
+
+ return hv_status;
+
+#else
+
+ u32 control_hi = control >> 32;
+ u32 control_lo = control & 0xFFFFFFFF;
+ u32 hv_status_hi = 1;
+ u32 hv_status_lo = 1;
+ u64 input_address = (input) ? virt_to_phys(input) : 0;
+ u32 input_address_hi = input_address >> 32;
+ u32 input_address_lo = input_address & 0xFFFFFFFF;
+ u64 output_address = (output) ? virt_to_phys(output) : 0;
+ u32 output_address_hi = output_address >> 32;
+ u32 output_address_lo = output_address & 0xFFFFFFFF;
+ void *hypercall_page = hv_context.hypercall_page;
+
+ __asm__ __volatile__ ("call *%8" : "=d"(hv_status_hi),
+ "=a"(hv_status_lo) : "d" (control_hi),
+ "a" (control_lo), "b" (input_address_hi),
+ "c" (input_address_lo), "D"(output_address_hi),
+ "S"(output_address_lo), "m" (hypercall_page));
+
+ return hv_status_lo | ((u64)hv_status_hi << 32);
+#endif /* !x86_64 */
+}
+
+/*
+ * hv_init - Main initialization routine.
+ *
+ * This routine must be called before any other routines in here are called
+ */
+int hv_init(void)
+{
+ int max_leaf;
+ union hv_x64_msr_hypercall_contents hypercall_msr;
+ void *virtaddr = NULL;
+
+ memset(hv_context.synic_event_page, 0, sizeof(void *) * NR_CPUS);
+ memset(hv_context.synic_message_page, 0,
+ sizeof(void *) * NR_CPUS);
+ memset(hv_context.post_msg_page, 0,
+ sizeof(void *) * NR_CPUS);
+ memset(hv_context.vp_index, 0,
+ sizeof(int) * NR_CPUS);
+ memset(hv_context.event_dpc, 0,
+ sizeof(void *) * NR_CPUS);
+ memset(hv_context.clk_evt, 0,
+ sizeof(void *) * NR_CPUS);
+
+ max_leaf = query_hypervisor_info();
+
+ /*
+ * Write our OS ID.
+ */
+ hv_context.guestid = generate_guest_id(0, LINUX_VERSION_CODE, 0);
+ wrmsrl(HV_X64_MSR_GUEST_OS_ID, hv_context.guestid);
+
+ /* See if the hypercall page is already set */
+ rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+ virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC);
+
+ if (!virtaddr)
+ goto cleanup;
+
+ hypercall_msr.enable = 1;
+
+ hypercall_msr.guest_physical_address = vmalloc_to_pfn(virtaddr);
+ wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+ /* Confirm that hypercall page did get setup. */
+ hypercall_msr.as_uint64 = 0;
+ rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+
+ if (!hypercall_msr.enable)
+ goto cleanup;
+
+ hv_context.hypercall_page = virtaddr;
+
+ return 0;
+
+cleanup:
+ if (virtaddr) {
+ if (hypercall_msr.enable) {
+ hypercall_msr.as_uint64 = 0;
+ wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+ }
+
+ vfree(virtaddr);
+ }
+
+ return -ENOTSUPP;
+}
+
+/*
+ * hv_cleanup - Cleanup routine.
+ *
+ * This routine is called normally during driver unloading or exiting.
+ */
+void hv_cleanup(void)
+{
+ union hv_x64_msr_hypercall_contents hypercall_msr;
+
+ /* Reset our OS id */
+ wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0);
+
+ if (hv_context.hypercall_page) {
+ hypercall_msr.as_uint64 = 0;
+ wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
+ vfree(hv_context.hypercall_page);
+ hv_context.hypercall_page = NULL;
+ }
+}
+
+/*
+ * hv_post_message - Post a message using the hypervisor message IPC.
+ *
+ * This involves a hypercall.
+ */
+int hv_post_message(union hv_connection_id connection_id,
+ enum hv_message_type message_type,
+ void *payload, size_t payload_size)
+{
+
+ struct hv_input_post_message *aligned_msg;
+ u16 status;
+
+ if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT)
+ return -EMSGSIZE;
+
+ aligned_msg = (struct hv_input_post_message *)
+ hv_context.post_msg_page[get_cpu()];
+
+ aligned_msg->connectionid = connection_id;
+ aligned_msg->reserved = 0;
+ aligned_msg->message_type = message_type;
+ aligned_msg->payload_size = payload_size;
+ memcpy((void *)aligned_msg->payload, payload, payload_size);
+
+ status = do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL)
+ & 0xFFFF;
+
+ put_cpu();
+ return status;
+}
+
+
+/*
+ * hv_signal_event -
+ * Signal an event on the specified connection using the hypervisor event IPC.
+ *
+ * This involves a hypercall.
+ */
+u16 hv_signal_event(void *con_id)
+{
+ u16 status;
+
+ status = (do_hypercall(HVCALL_SIGNAL_EVENT, con_id, NULL) & 0xFFFF);
+
+ return status;
+}
+
+static int hv_ce_set_next_event(unsigned long delta,
+ struct clock_event_device *evt)
+{
+ cycle_t current_tick;
+
+ WARN_ON(evt->mode != CLOCK_EVT_MODE_ONESHOT);
+
+ rdmsrl(HV_X64_MSR_TIME_REF_COUNT, current_tick);
+ current_tick += delta;
+ wrmsrl(HV_X64_MSR_STIMER0_COUNT, current_tick);
+ return 0;
+}
+
+static void hv_ce_setmode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ union hv_timer_config timer_cfg;
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ /* unsupported */
+ break;
+
+ case CLOCK_EVT_MODE_ONESHOT:
+ timer_cfg.enable = 1;
+ timer_cfg.auto_enable = 1;
+ timer_cfg.sintx = VMBUS_MESSAGE_SINT;
+ wrmsrl(HV_X64_MSR_STIMER0_CONFIG, timer_cfg.as_uint64);
+ break;
+
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ wrmsrl(HV_X64_MSR_STIMER0_COUNT, 0);
+ wrmsrl(HV_X64_MSR_STIMER0_CONFIG, 0);
+ break;
+ case CLOCK_EVT_MODE_RESUME:
+ break;
+ }
+}
+
+static void hv_init_clockevent_device(struct clock_event_device *dev, int cpu)
+{
+ dev->name = "Hyper-V clockevent";
+ dev->features = CLOCK_EVT_FEAT_ONESHOT;
+ dev->cpumask = cpumask_of(cpu);
+ dev->rating = 1000;
+ /*
+ * Avoid settint dev->owner = THIS_MODULE deliberately as doing so will
+ * result in clockevents_config_and_register() taking additional
+ * references to the hv_vmbus module making it impossible to unload.
+ */
+
+ dev->set_mode = hv_ce_setmode;
+ dev->set_next_event = hv_ce_set_next_event;
+}
+
+
+int hv_synic_alloc(void)
+{
+ size_t size = sizeof(struct tasklet_struct);
+ size_t ced_size = sizeof(struct clock_event_device);
+ int cpu;
+
+ for_each_online_cpu(cpu) {
+ hv_context.event_dpc[cpu] = kmalloc(size, GFP_ATOMIC);
+ if (hv_context.event_dpc[cpu] == NULL) {
+ pr_err("Unable to allocate event dpc\n");
+ goto err;
+ }
+ tasklet_init(hv_context.event_dpc[cpu], vmbus_on_event, cpu);
+
+ hv_context.clk_evt[cpu] = kzalloc(ced_size, GFP_ATOMIC);
+ if (hv_context.clk_evt[cpu] == NULL) {
+ pr_err("Unable to allocate clock event device\n");
+ goto err;
+ }
+ hv_init_clockevent_device(hv_context.clk_evt[cpu], cpu);
+
+ hv_context.synic_message_page[cpu] =
+ (void *)get_zeroed_page(GFP_ATOMIC);
+
+ if (hv_context.synic_message_page[cpu] == NULL) {
+ pr_err("Unable to allocate SYNIC message page\n");
+ goto err;
+ }
+
+ hv_context.synic_event_page[cpu] =
+ (void *)get_zeroed_page(GFP_ATOMIC);
+
+ if (hv_context.synic_event_page[cpu] == NULL) {
+ pr_err("Unable to allocate SYNIC event page\n");
+ goto err;
+ }
+
+ hv_context.post_msg_page[cpu] =
+ (void *)get_zeroed_page(GFP_ATOMIC);
+
+ if (hv_context.post_msg_page[cpu] == NULL) {
+ pr_err("Unable to allocate post msg page\n");
+ goto err;
+ }
+ }
+
+ return 0;
+err:
+ return -ENOMEM;
+}
+
+static void hv_synic_free_cpu(int cpu)
+{
+ kfree(hv_context.event_dpc[cpu]);
+ kfree(hv_context.clk_evt[cpu]);
+ if (hv_context.synic_event_page[cpu])
+ free_page((unsigned long)hv_context.synic_event_page[cpu]);
+ if (hv_context.synic_message_page[cpu])
+ free_page((unsigned long)hv_context.synic_message_page[cpu]);
+ if (hv_context.post_msg_page[cpu])
+ free_page((unsigned long)hv_context.post_msg_page[cpu]);
+}
+
+void hv_synic_free(void)
+{
+ int cpu;
+
+ for_each_online_cpu(cpu)
+ hv_synic_free_cpu(cpu);
+}
+
+/*
+ * hv_synic_init - Initialize the Synthethic Interrupt Controller.
+ *
+ * If it is already initialized by another entity (ie x2v shim), we need to
+ * retrieve the initialized message and event pages. Otherwise, we create and
+ * initialize the message and event pages.
+ */
+void hv_synic_init(void *arg)
+{
+ u64 version;
+ union hv_synic_simp simp;
+ union hv_synic_siefp siefp;
+ union hv_synic_sint shared_sint;
+ union hv_synic_scontrol sctrl;
+ u64 vp_index;
+
+ int cpu = smp_processor_id();
+
+ if (!hv_context.hypercall_page)
+ return;
+
+ /* Check the version */
+ rdmsrl(HV_X64_MSR_SVERSION, version);
+
+ /* Setup the Synic's message page */
+ rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
+ simp.simp_enabled = 1;
+ simp.base_simp_gpa = virt_to_phys(hv_context.synic_message_page[cpu])
+ >> PAGE_SHIFT;
+
+ wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
+
+ /* Setup the Synic's event page */
+ rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
+ siefp.siefp_enabled = 1;
+ siefp.base_siefp_gpa = virt_to_phys(hv_context.synic_event_page[cpu])
+ >> PAGE_SHIFT;
+
+ wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
+
+ /* Setup the shared SINT. */
+ rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+
+ shared_sint.as_uint64 = 0;
+ shared_sint.vector = HYPERVISOR_CALLBACK_VECTOR;
+ shared_sint.masked = false;
+ shared_sint.auto_eoi = true;
+
+ wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+
+ /* Enable the global synic bit */
+ rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
+ sctrl.enable = 1;
+
+ wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
+
+ hv_context.synic_initialized = true;
+
+ /*
+ * Setup the mapping between Hyper-V's notion
+ * of cpuid and Linux' notion of cpuid.
+ * This array will be indexed using Linux cpuid.
+ */
+ rdmsrl(HV_X64_MSR_VP_INDEX, vp_index);
+ hv_context.vp_index[cpu] = (u32)vp_index;
+
+ INIT_LIST_HEAD(&hv_context.percpu_list[cpu]);
+
+ /*
+ * Register the per-cpu clockevent source.
+ */
+ if (ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE)
+ clockevents_config_and_register(hv_context.clk_evt[cpu],
+ HV_TIMER_FREQUENCY,
+ HV_MIN_DELTA_TICKS,
+ HV_MAX_MAX_DELTA_TICKS);
+ return;
+}
+
+/*
+ * hv_synic_clockevents_cleanup - Cleanup clockevent devices
+ */
+void hv_synic_clockevents_cleanup(void)
+{
+ int cpu;
+
+ if (!(ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE))
+ return;
+
+ for_each_online_cpu(cpu)
+ clockevents_unbind_device(hv_context.clk_evt[cpu], cpu);
+}
+
+/*
+ * hv_synic_cleanup - Cleanup routine for hv_synic_init().
+ */
+void hv_synic_cleanup(void *arg)
+{
+ union hv_synic_sint shared_sint;
+ union hv_synic_simp simp;
+ union hv_synic_siefp siefp;
+ union hv_synic_scontrol sctrl;
+ int cpu = smp_processor_id();
+
+ if (!hv_context.synic_initialized)
+ return;
+
+ /* Turn off clockevent device */
+ if (ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE)
+ hv_ce_setmode(CLOCK_EVT_MODE_SHUTDOWN,
+ hv_context.clk_evt[cpu]);
+
+ rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+
+ shared_sint.masked = 1;
+
+ /* Need to correctly cleanup in the case of SMP!!! */
+ /* Disable the interrupt */
+ wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+
+ rdmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
+ simp.simp_enabled = 0;
+ simp.base_simp_gpa = 0;
+
+ wrmsrl(HV_X64_MSR_SIMP, simp.as_uint64);
+
+ rdmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
+ siefp.siefp_enabled = 0;
+ siefp.base_siefp_gpa = 0;
+
+ wrmsrl(HV_X64_MSR_SIEFP, siefp.as_uint64);
+
+ /* Disable the global synic bit */
+ rdmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
+ sctrl.enable = 0;
+ wrmsrl(HV_X64_MSR_SCONTROL, sctrl.as_uint64);
+
+ hv_synic_free_cpu(cpu);
+}
diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
new file mode 100644
index 000000000..cb5b7dc97
--- /dev/null
+++ b/drivers/hv/hv_balloon.c
@@ -0,0 +1,1616 @@
+/*
+ * Copyright (c) 2012, Microsoft Corporation.
+ *
+ * Author:
+ * K. Y. Srinivasan <kys@microsoft.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for more
+ * details.
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/jiffies.h>
+#include <linux/mman.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/kthread.h>
+#include <linux/completion.h>
+#include <linux/memory_hotplug.h>
+#include <linux/memory.h>
+#include <linux/notifier.h>
+#include <linux/percpu_counter.h>
+
+#include <linux/hyperv.h>
+
+/*
+ * We begin with definitions supporting the Dynamic Memory protocol
+ * with the host.
+ *
+ * Begin protocol definitions.
+ */
+
+
+
+/*
+ * Protocol versions. The low word is the minor version, the high word the major
+ * version.
+ *
+ * History:
+ * Initial version 1.0
+ * Changed to 0.1 on 2009/03/25
+ * Changes to 0.2 on 2009/05/14
+ * Changes to 0.3 on 2009/12/03
+ * Changed to 1.0 on 2011/04/05
+ */
+
+#define DYNMEM_MAKE_VERSION(Major, Minor) ((__u32)(((Major) << 16) | (Minor)))
+#define DYNMEM_MAJOR_VERSION(Version) ((__u32)(Version) >> 16)
+#define DYNMEM_MINOR_VERSION(Version) ((__u32)(Version) & 0xff)
+
+enum {
+ DYNMEM_PROTOCOL_VERSION_1 = DYNMEM_MAKE_VERSION(0, 3),
+ DYNMEM_PROTOCOL_VERSION_2 = DYNMEM_MAKE_VERSION(1, 0),
+
+ DYNMEM_PROTOCOL_VERSION_WIN7 = DYNMEM_PROTOCOL_VERSION_1,
+ DYNMEM_PROTOCOL_VERSION_WIN8 = DYNMEM_PROTOCOL_VERSION_2,
+
+ DYNMEM_PROTOCOL_VERSION_CURRENT = DYNMEM_PROTOCOL_VERSION_WIN8
+};
+
+
+
+/*
+ * Message Types
+ */
+
+enum dm_message_type {
+ /*
+ * Version 0.3
+ */
+ DM_ERROR = 0,
+ DM_VERSION_REQUEST = 1,
+ DM_VERSION_RESPONSE = 2,
+ DM_CAPABILITIES_REPORT = 3,
+ DM_CAPABILITIES_RESPONSE = 4,
+ DM_STATUS_REPORT = 5,
+ DM_BALLOON_REQUEST = 6,
+ DM_BALLOON_RESPONSE = 7,
+ DM_UNBALLOON_REQUEST = 8,
+ DM_UNBALLOON_RESPONSE = 9,
+ DM_MEM_HOT_ADD_REQUEST = 10,
+ DM_MEM_HOT_ADD_RESPONSE = 11,
+ DM_VERSION_03_MAX = 11,
+ /*
+ * Version 1.0.
+ */
+ DM_INFO_MESSAGE = 12,
+ DM_VERSION_1_MAX = 12
+};
+
+
+/*
+ * Structures defining the dynamic memory management
+ * protocol.
+ */
+
+union dm_version {
+ struct {
+ __u16 minor_version;
+ __u16 major_version;
+ };
+ __u32 version;
+} __packed;
+
+
+union dm_caps {
+ struct {
+ __u64 balloon:1;
+ __u64 hot_add:1;
+ /*
+ * To support guests that may have alignment
+ * limitations on hot-add, the guest can specify
+ * its alignment requirements; a value of n
+ * represents an alignment of 2^n in mega bytes.
+ */
+ __u64 hot_add_alignment:4;
+ __u64 reservedz:58;
+ } cap_bits;
+ __u64 caps;
+} __packed;
+
+union dm_mem_page_range {
+ struct {
+ /*
+ * The PFN number of the first page in the range.
+ * 40 bits is the architectural limit of a PFN
+ * number for AMD64.
+ */
+ __u64 start_page:40;
+ /*
+ * The number of pages in the range.
+ */
+ __u64 page_cnt:24;
+ } finfo;
+ __u64 page_range;
+} __packed;
+
+
+
+/*
+ * The header for all dynamic memory messages:
+ *
+ * type: Type of the message.
+ * size: Size of the message in bytes; including the header.
+ * trans_id: The guest is responsible for manufacturing this ID.
+ */
+
+struct dm_header {
+ __u16 type;
+ __u16 size;
+ __u32 trans_id;
+} __packed;
+
+/*
+ * A generic message format for dynamic memory.
+ * Specific message formats are defined later in the file.
+ */
+
+struct dm_message {
+ struct dm_header hdr;
+ __u8 data[]; /* enclosed message */
+} __packed;
+
+
+/*
+ * Specific message types supporting the dynamic memory protocol.
+ */
+
+/*
+ * Version negotiation message. Sent from the guest to the host.
+ * The guest is free to try different versions until the host
+ * accepts the version.
+ *
+ * dm_version: The protocol version requested.
+ * is_last_attempt: If TRUE, this is the last version guest will request.
+ * reservedz: Reserved field, set to zero.
+ */
+
+struct dm_version_request {
+ struct dm_header hdr;
+ union dm_version version;
+ __u32 is_last_attempt:1;
+ __u32 reservedz:31;
+} __packed;
+
+/*
+ * Version response message; Host to Guest and indicates
+ * if the host has accepted the version sent by the guest.
+ *
+ * is_accepted: If TRUE, host has accepted the version and the guest
+ * should proceed to the next stage of the protocol. FALSE indicates that
+ * guest should re-try with a different version.
+ *
+ * reservedz: Reserved field, set to zero.
+ */
+
+struct dm_version_response {
+ struct dm_header hdr;
+ __u64 is_accepted:1;
+ __u64 reservedz:63;
+} __packed;
+
+/*
+ * Message reporting capabilities. This is sent from the guest to the
+ * host.
+ */
+
+struct dm_capabilities {
+ struct dm_header hdr;
+ union dm_caps caps;
+ __u64 min_page_cnt;
+ __u64 max_page_number;
+} __packed;
+
+/*
+ * Response to the capabilities message. This is sent from the host to the
+ * guest. This message notifies if the host has accepted the guest's
+ * capabilities. If the host has not accepted, the guest must shutdown
+ * the service.
+ *
+ * is_accepted: Indicates if the host has accepted guest's capabilities.
+ * reservedz: Must be 0.
+ */
+
+struct dm_capabilities_resp_msg {
+ struct dm_header hdr;
+ __u64 is_accepted:1;
+ __u64 reservedz:63;
+} __packed;
+
+/*
+ * This message is used to report memory pressure from the guest.
+ * This message is not part of any transaction and there is no
+ * response to this message.
+ *
+ * num_avail: Available memory in pages.
+ * num_committed: Committed memory in pages.
+ * page_file_size: The accumulated size of all page files
+ * in the system in pages.
+ * zero_free: The nunber of zero and free pages.
+ * page_file_writes: The writes to the page file in pages.
+ * io_diff: An indicator of file cache efficiency or page file activity,
+ * calculated as File Cache Page Fault Count - Page Read Count.
+ * This value is in pages.
+ *
+ * Some of these metrics are Windows specific and fortunately
+ * the algorithm on the host side that computes the guest memory
+ * pressure only uses num_committed value.
+ */
+
+struct dm_status {
+ struct dm_header hdr;
+ __u64 num_avail;
+ __u64 num_committed;
+ __u64 page_file_size;
+ __u64 zero_free;
+ __u32 page_file_writes;
+ __u32 io_diff;
+} __packed;
+
+
+/*
+ * Message to ask the guest to allocate memory - balloon up message.
+ * This message is sent from the host to the guest. The guest may not be
+ * able to allocate as much memory as requested.
+ *
+ * num_pages: number of pages to allocate.
+ */
+
+struct dm_balloon {
+ struct dm_header hdr;
+ __u32 num_pages;
+ __u32 reservedz;
+} __packed;
+
+
+/*
+ * Balloon response message; this message is sent from the guest
+ * to the host in response to the balloon message.
+ *
+ * reservedz: Reserved; must be set to zero.
+ * more_pages: If FALSE, this is the last message of the transaction.
+ * if TRUE there will atleast one more message from the guest.
+ *
+ * range_count: The number of ranges in the range array.
+ *
+ * range_array: An array of page ranges returned to the host.
+ *
+ */
+
+struct dm_balloon_response {
+ struct dm_header hdr;
+ __u32 reservedz;
+ __u32 more_pages:1;
+ __u32 range_count:31;
+ union dm_mem_page_range range_array[];
+} __packed;
+
+/*
+ * Un-balloon message; this message is sent from the host
+ * to the guest to give guest more memory.
+ *
+ * more_pages: If FALSE, this is the last message of the transaction.
+ * if TRUE there will atleast one more message from the guest.
+ *
+ * reservedz: Reserved; must be set to zero.
+ *
+ * range_count: The number of ranges in the range array.
+ *
+ * range_array: An array of page ranges returned to the host.
+ *
+ */
+
+struct dm_unballoon_request {
+ struct dm_header hdr;
+ __u32 more_pages:1;
+ __u32 reservedz:31;
+ __u32 range_count;
+ union dm_mem_page_range range_array[];
+} __packed;
+
+/*
+ * Un-balloon response message; this message is sent from the guest
+ * to the host in response to an unballoon request.
+ *
+ */
+
+struct dm_unballoon_response {
+ struct dm_header hdr;
+} __packed;
+
+
+/*
+ * Hot add request message. Message sent from the host to the guest.
+ *
+ * mem_range: Memory range to hot add.
+ *
+ * On Linux we currently don't support this since we cannot hot add
+ * arbitrary granularity of memory.
+ */
+
+struct dm_hot_add {
+ struct dm_header hdr;
+ union dm_mem_page_range range;
+} __packed;
+
+/*
+ * Hot add response message.
+ * This message is sent by the guest to report the status of a hot add request.
+ * If page_count is less than the requested page count, then the host should
+ * assume all further hot add requests will fail, since this indicates that
+ * the guest has hit an upper physical memory barrier.
+ *
+ * Hot adds may also fail due to low resources; in this case, the guest must
+ * not complete this message until the hot add can succeed, and the host must
+ * not send a new hot add request until the response is sent.
+ * If VSC fails to hot add memory DYNMEM_NUMBER_OF_UNSUCCESSFUL_HOTADD_ATTEMPTS
+ * times it fails the request.
+ *
+ *
+ * page_count: number of pages that were successfully hot added.
+ *
+ * result: result of the operation 1: success, 0: failure.
+ *
+ */
+
+struct dm_hot_add_response {
+ struct dm_header hdr;
+ __u32 page_count;
+ __u32 result;
+} __packed;
+
+/*
+ * Types of information sent from host to the guest.
+ */
+
+enum dm_info_type {
+ INFO_TYPE_MAX_PAGE_CNT = 0,
+ MAX_INFO_TYPE
+};
+
+
+/*
+ * Header for the information message.
+ */
+
+struct dm_info_header {
+ enum dm_info_type type;
+ __u32 data_size;
+} __packed;
+
+/*
+ * This message is sent from the host to the guest to pass
+ * some relevant information (win8 addition).
+ *
+ * reserved: no used.
+ * info_size: size of the information blob.
+ * info: information blob.
+ */
+
+struct dm_info_msg {
+ struct dm_header hdr;
+ __u32 reserved;
+ __u32 info_size;
+ __u8 info[];
+};
+
+/*
+ * End protocol definitions.
+ */
+
+/*
+ * State to manage hot adding memory into the guest.
+ * The range start_pfn : end_pfn specifies the range
+ * that the host has asked us to hot add. The range
+ * start_pfn : ha_end_pfn specifies the range that we have
+ * currently hot added. We hot add in multiples of 128M
+ * chunks; it is possible that we may not be able to bring
+ * online all the pages in the region. The range
+ * covered_end_pfn defines the pages that can
+ * be brough online.
+ */
+
+struct hv_hotadd_state {
+ struct list_head list;
+ unsigned long start_pfn;
+ unsigned long covered_end_pfn;
+ unsigned long ha_end_pfn;
+ unsigned long end_pfn;
+};
+
+struct balloon_state {
+ __u32 num_pages;
+ struct work_struct wrk;
+};
+
+struct hot_add_wrk {
+ union dm_mem_page_range ha_page_range;
+ union dm_mem_page_range ha_region_range;
+ struct work_struct wrk;
+};
+
+static bool hot_add = true;
+static bool do_hot_add;
+/*
+ * Delay reporting memory pressure by
+ * the specified number of seconds.
+ */
+static uint pressure_report_delay = 45;
+
+/*
+ * The last time we posted a pressure report to host.
+ */
+static unsigned long last_post_time;
+
+module_param(hot_add, bool, (S_IRUGO | S_IWUSR));
+MODULE_PARM_DESC(hot_add, "If set attempt memory hot_add");
+
+module_param(pressure_report_delay, uint, (S_IRUGO | S_IWUSR));
+MODULE_PARM_DESC(pressure_report_delay, "Delay in secs in reporting pressure");
+static atomic_t trans_id = ATOMIC_INIT(0);
+
+static int dm_ring_size = (5 * PAGE_SIZE);
+
+/*
+ * Driver specific state.
+ */
+
+enum hv_dm_state {
+ DM_INITIALIZING = 0,
+ DM_INITIALIZED,
+ DM_BALLOON_UP,
+ DM_BALLOON_DOWN,
+ DM_HOT_ADD,
+ DM_INIT_ERROR
+};
+
+
+static __u8 recv_buffer[PAGE_SIZE];
+static __u8 *send_buffer;
+#define PAGES_IN_2M 512
+#define HA_CHUNK (32 * 1024)
+
+struct hv_dynmem_device {
+ struct hv_device *dev;
+ enum hv_dm_state state;
+ struct completion host_event;
+ struct completion config_event;
+
+ /*
+ * Number of pages we have currently ballooned out.
+ */
+ unsigned int num_pages_ballooned;
+ unsigned int num_pages_onlined;
+ unsigned int num_pages_added;
+
+ /*
+ * State to manage the ballooning (up) operation.
+ */
+ struct balloon_state balloon_wrk;
+
+ /*
+ * State to execute the "hot-add" operation.
+ */
+ struct hot_add_wrk ha_wrk;
+
+ /*
+ * This state tracks if the host has specified a hot-add
+ * region.
+ */
+ bool host_specified_ha_region;
+
+ /*
+ * State to synchronize hot-add.
+ */
+ struct completion ol_waitevent;
+ bool ha_waiting;
+ /*
+ * This thread handles hot-add
+ * requests from the host as well as notifying
+ * the host with regards to memory pressure in
+ * the guest.
+ */
+ struct task_struct *thread;
+
+ struct mutex ha_region_mutex;
+
+ /*
+ * A list of hot-add regions.
+ */
+ struct list_head ha_region_list;
+
+ /*
+ * We start with the highest version we can support
+ * and downgrade based on the host; we save here the
+ * next version to try.
+ */
+ __u32 next_version;
+};
+
+static struct hv_dynmem_device dm_device;
+
+static void post_status(struct hv_dynmem_device *dm);
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+static int hv_memory_notifier(struct notifier_block *nb, unsigned long val,
+ void *v)
+{
+ struct memory_notify *mem = (struct memory_notify *)v;
+
+ switch (val) {
+ case MEM_GOING_ONLINE:
+ mutex_lock(&dm_device.ha_region_mutex);
+ break;
+
+ case MEM_ONLINE:
+ dm_device.num_pages_onlined += mem->nr_pages;
+ case MEM_CANCEL_ONLINE:
+ mutex_unlock(&dm_device.ha_region_mutex);
+ if (dm_device.ha_waiting) {
+ dm_device.ha_waiting = false;
+ complete(&dm_device.ol_waitevent);
+ }
+ break;
+
+ case MEM_OFFLINE:
+ mutex_lock(&dm_device.ha_region_mutex);
+ dm_device.num_pages_onlined -= mem->nr_pages;
+ mutex_unlock(&dm_device.ha_region_mutex);
+ break;
+ case MEM_GOING_OFFLINE:
+ case MEM_CANCEL_OFFLINE:
+ break;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block hv_memory_nb = {
+ .notifier_call = hv_memory_notifier,
+ .priority = 0
+};
+
+
+static void hv_bring_pgs_online(unsigned long start_pfn, unsigned long size)
+{
+ int i;
+
+ for (i = 0; i < size; i++) {
+ struct page *pg;
+ pg = pfn_to_page(start_pfn + i);
+ __online_page_set_limits(pg);
+ __online_page_increment_counters(pg);
+ __online_page_free(pg);
+ }
+}
+
+static void hv_mem_hot_add(unsigned long start, unsigned long size,
+ unsigned long pfn_count,
+ struct hv_hotadd_state *has)
+{
+ int ret = 0;
+ int i, nid;
+ unsigned long start_pfn;
+ unsigned long processed_pfn;
+ unsigned long total_pfn = pfn_count;
+
+ for (i = 0; i < (size/HA_CHUNK); i++) {
+ start_pfn = start + (i * HA_CHUNK);
+ has->ha_end_pfn += HA_CHUNK;
+
+ if (total_pfn > HA_CHUNK) {
+ processed_pfn = HA_CHUNK;
+ total_pfn -= HA_CHUNK;
+ } else {
+ processed_pfn = total_pfn;
+ total_pfn = 0;
+ }
+
+ has->covered_end_pfn += processed_pfn;
+
+ init_completion(&dm_device.ol_waitevent);
+ dm_device.ha_waiting = true;
+
+ mutex_unlock(&dm_device.ha_region_mutex);
+ nid = memory_add_physaddr_to_nid(PFN_PHYS(start_pfn));
+ ret = add_memory(nid, PFN_PHYS((start_pfn)),
+ (HA_CHUNK << PAGE_SHIFT));
+
+ if (ret) {
+ pr_info("hot_add memory failed error is %d\n", ret);
+ if (ret == -EEXIST) {
+ /*
+ * This error indicates that the error
+ * is not a transient failure. This is the
+ * case where the guest's physical address map
+ * precludes hot adding memory. Stop all further
+ * memory hot-add.
+ */
+ do_hot_add = false;
+ }
+ has->ha_end_pfn -= HA_CHUNK;
+ has->covered_end_pfn -= processed_pfn;
+ mutex_lock(&dm_device.ha_region_mutex);
+ break;
+ }
+
+ /*
+ * Wait for the memory block to be onlined.
+ * Since the hot add has succeeded, it is ok to
+ * proceed even if the pages in the hot added region
+ * have not been "onlined" within the allowed time.
+ */
+ wait_for_completion_timeout(&dm_device.ol_waitevent, 5*HZ);
+ mutex_lock(&dm_device.ha_region_mutex);
+ post_status(&dm_device);
+ }
+
+ return;
+}
+
+static void hv_online_page(struct page *pg)
+{
+ struct list_head *cur;
+ struct hv_hotadd_state *has;
+ unsigned long cur_start_pgp;
+ unsigned long cur_end_pgp;
+
+ list_for_each(cur, &dm_device.ha_region_list) {
+ has = list_entry(cur, struct hv_hotadd_state, list);
+ cur_start_pgp = (unsigned long)pfn_to_page(has->start_pfn);
+ cur_end_pgp = (unsigned long)pfn_to_page(has->covered_end_pfn);
+
+ if (((unsigned long)pg >= cur_start_pgp) &&
+ ((unsigned long)pg < cur_end_pgp)) {
+ /*
+ * This frame is currently backed; online the
+ * page.
+ */
+ __online_page_set_limits(pg);
+ __online_page_increment_counters(pg);
+ __online_page_free(pg);
+ }
+ }
+}
+
+static bool pfn_covered(unsigned long start_pfn, unsigned long pfn_cnt)
+{
+ struct list_head *cur;
+ struct hv_hotadd_state *has;
+ unsigned long residual, new_inc;
+
+ if (list_empty(&dm_device.ha_region_list))
+ return false;
+
+ list_for_each(cur, &dm_device.ha_region_list) {
+ has = list_entry(cur, struct hv_hotadd_state, list);
+
+ /*
+ * If the pfn range we are dealing with is not in the current
+ * "hot add block", move on.
+ */
+ if ((start_pfn >= has->end_pfn))
+ continue;
+ /*
+ * If the current hot add-request extends beyond
+ * our current limit; extend it.
+ */
+ if ((start_pfn + pfn_cnt) > has->end_pfn) {
+ residual = (start_pfn + pfn_cnt - has->end_pfn);
+ /*
+ * Extend the region by multiples of HA_CHUNK.
+ */
+ new_inc = (residual / HA_CHUNK) * HA_CHUNK;
+ if (residual % HA_CHUNK)
+ new_inc += HA_CHUNK;
+
+ has->end_pfn += new_inc;
+ }
+
+ /*
+ * If the current start pfn is not where the covered_end
+ * is, update it.
+ */
+
+ if (has->covered_end_pfn != start_pfn)
+ has->covered_end_pfn = start_pfn;
+
+ return true;
+
+ }
+
+ return false;
+}
+
+static unsigned long handle_pg_range(unsigned long pg_start,
+ unsigned long pg_count)
+{
+ unsigned long start_pfn = pg_start;
+ unsigned long pfn_cnt = pg_count;
+ unsigned long size;
+ struct list_head *cur;
+ struct hv_hotadd_state *has;
+ unsigned long pgs_ol = 0;
+ unsigned long old_covered_state;
+
+ if (list_empty(&dm_device.ha_region_list))
+ return 0;
+
+ list_for_each(cur, &dm_device.ha_region_list) {
+ has = list_entry(cur, struct hv_hotadd_state, list);
+
+ /*
+ * If the pfn range we are dealing with is not in the current
+ * "hot add block", move on.
+ */
+ if ((start_pfn >= has->end_pfn))
+ continue;
+
+ old_covered_state = has->covered_end_pfn;
+
+ if (start_pfn < has->ha_end_pfn) {
+ /*
+ * This is the case where we are backing pages
+ * in an already hot added region. Bring
+ * these pages online first.
+ */
+ pgs_ol = has->ha_end_pfn - start_pfn;
+ if (pgs_ol > pfn_cnt)
+ pgs_ol = pfn_cnt;
+
+ /*
+ * Check if the corresponding memory block is already
+ * online by checking its last previously backed page.
+ * In case it is we need to bring rest (which was not
+ * backed previously) online too.
+ */
+ if (start_pfn > has->start_pfn &&
+ !PageReserved(pfn_to_page(start_pfn - 1)))
+ hv_bring_pgs_online(start_pfn, pgs_ol);
+
+ has->covered_end_pfn += pgs_ol;
+ pfn_cnt -= pgs_ol;
+ }
+
+ if ((has->ha_end_pfn < has->end_pfn) && (pfn_cnt > 0)) {
+ /*
+ * We have some residual hot add range
+ * that needs to be hot added; hot add
+ * it now. Hot add a multiple of
+ * of HA_CHUNK that fully covers the pages
+ * we have.
+ */
+ size = (has->end_pfn - has->ha_end_pfn);
+ if (pfn_cnt <= size) {
+ size = ((pfn_cnt / HA_CHUNK) * HA_CHUNK);
+ if (pfn_cnt % HA_CHUNK)
+ size += HA_CHUNK;
+ } else {
+ pfn_cnt = size;
+ }
+ hv_mem_hot_add(has->ha_end_pfn, size, pfn_cnt, has);
+ }
+ /*
+ * If we managed to online any pages that were given to us,
+ * we declare success.
+ */
+ return has->covered_end_pfn - old_covered_state;
+
+ }
+
+ return 0;
+}
+
+static unsigned long process_hot_add(unsigned long pg_start,
+ unsigned long pfn_cnt,
+ unsigned long rg_start,
+ unsigned long rg_size)
+{
+ struct hv_hotadd_state *ha_region = NULL;
+
+ if (pfn_cnt == 0)
+ return 0;
+
+ if (!dm_device.host_specified_ha_region)
+ if (pfn_covered(pg_start, pfn_cnt))
+ goto do_pg_range;
+
+ /*
+ * If the host has specified a hot-add range; deal with it first.
+ */
+
+ if (rg_size != 0) {
+ ha_region = kzalloc(sizeof(struct hv_hotadd_state), GFP_KERNEL);
+ if (!ha_region)
+ return 0;
+
+ INIT_LIST_HEAD(&ha_region->list);
+
+ list_add_tail(&ha_region->list, &dm_device.ha_region_list);
+ ha_region->start_pfn = rg_start;
+ ha_region->ha_end_pfn = rg_start;
+ ha_region->covered_end_pfn = pg_start;
+ ha_region->end_pfn = rg_start + rg_size;
+ }
+
+do_pg_range:
+ /*
+ * Process the page range specified; bringing them
+ * online if possible.
+ */
+ return handle_pg_range(pg_start, pfn_cnt);
+}
+
+#endif
+
+static void hot_add_req(struct work_struct *dummy)
+{
+ struct dm_hot_add_response resp;
+#ifdef CONFIG_MEMORY_HOTPLUG
+ unsigned long pg_start, pfn_cnt;
+ unsigned long rg_start, rg_sz;
+#endif
+ struct hv_dynmem_device *dm = &dm_device;
+
+ memset(&resp, 0, sizeof(struct dm_hot_add_response));
+ resp.hdr.type = DM_MEM_HOT_ADD_RESPONSE;
+ resp.hdr.size = sizeof(struct dm_hot_add_response);
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+ mutex_lock(&dm_device.ha_region_mutex);
+ pg_start = dm->ha_wrk.ha_page_range.finfo.start_page;
+ pfn_cnt = dm->ha_wrk.ha_page_range.finfo.page_cnt;
+
+ rg_start = dm->ha_wrk.ha_region_range.finfo.start_page;
+ rg_sz = dm->ha_wrk.ha_region_range.finfo.page_cnt;
+
+ if ((rg_start == 0) && (!dm->host_specified_ha_region)) {
+ unsigned long region_size;
+ unsigned long region_start;
+
+ /*
+ * The host has not specified the hot-add region.
+ * Based on the hot-add page range being specified,
+ * compute a hot-add region that can cover the pages
+ * that need to be hot-added while ensuring the alignment
+ * and size requirements of Linux as it relates to hot-add.
+ */
+ region_start = pg_start;
+ region_size = (pfn_cnt / HA_CHUNK) * HA_CHUNK;
+ if (pfn_cnt % HA_CHUNK)
+ region_size += HA_CHUNK;
+
+ region_start = (pg_start / HA_CHUNK) * HA_CHUNK;
+
+ rg_start = region_start;
+ rg_sz = region_size;
+ }
+
+ if (do_hot_add)
+ resp.page_count = process_hot_add(pg_start, pfn_cnt,
+ rg_start, rg_sz);
+
+ dm->num_pages_added += resp.page_count;
+ mutex_unlock(&dm_device.ha_region_mutex);
+#endif
+ /*
+ * The result field of the response structure has the
+ * following semantics:
+ *
+ * 1. If all or some pages hot-added: Guest should return success.
+ *
+ * 2. If no pages could be hot-added:
+ *
+ * If the guest returns success, then the host
+ * will not attempt any further hot-add operations. This
+ * signifies a permanent failure.
+ *
+ * If the guest returns failure, then this failure will be
+ * treated as a transient failure and the host may retry the
+ * hot-add operation after some delay.
+ */
+ if (resp.page_count > 0)
+ resp.result = 1;
+ else if (!do_hot_add)
+ resp.result = 1;
+ else
+ resp.result = 0;
+
+ if (!do_hot_add || (resp.page_count == 0))
+ pr_info("Memory hot add failed\n");
+
+ dm->state = DM_INITIALIZED;
+ resp.hdr.trans_id = atomic_inc_return(&trans_id);
+ vmbus_sendpacket(dm->dev->channel, &resp,
+ sizeof(struct dm_hot_add_response),
+ (unsigned long)NULL,
+ VM_PKT_DATA_INBAND, 0);
+}
+
+static void process_info(struct hv_dynmem_device *dm, struct dm_info_msg *msg)
+{
+ struct dm_info_header *info_hdr;
+
+ info_hdr = (struct dm_info_header *)msg->info;
+
+ switch (info_hdr->type) {
+ case INFO_TYPE_MAX_PAGE_CNT:
+ pr_info("Received INFO_TYPE_MAX_PAGE_CNT\n");
+ pr_info("Data Size is %d\n", info_hdr->data_size);
+ break;
+ default:
+ pr_info("Received Unknown type: %d\n", info_hdr->type);
+ }
+}
+
+static unsigned long compute_balloon_floor(void)
+{
+ unsigned long min_pages;
+#define MB2PAGES(mb) ((mb) << (20 - PAGE_SHIFT))
+ /* Simple continuous piecewiese linear function:
+ * max MiB -> min MiB gradient
+ * 0 0
+ * 16 16
+ * 32 24
+ * 128 72 (1/2)
+ * 512 168 (1/4)
+ * 2048 360 (1/8)
+ * 8192 744 (1/16)
+ * 32768 1512 (1/32)
+ */
+ if (totalram_pages < MB2PAGES(128))
+ min_pages = MB2PAGES(8) + (totalram_pages >> 1);
+ else if (totalram_pages < MB2PAGES(512))
+ min_pages = MB2PAGES(40) + (totalram_pages >> 2);
+ else if (totalram_pages < MB2PAGES(2048))
+ min_pages = MB2PAGES(104) + (totalram_pages >> 3);
+ else if (totalram_pages < MB2PAGES(8192))
+ min_pages = MB2PAGES(232) + (totalram_pages >> 4);
+ else
+ min_pages = MB2PAGES(488) + (totalram_pages >> 5);
+#undef MB2PAGES
+ return min_pages;
+}
+
+/*
+ * Post our status as it relates memory pressure to the
+ * host. Host expects the guests to post this status
+ * periodically at 1 second intervals.
+ *
+ * The metrics specified in this protocol are very Windows
+ * specific and so we cook up numbers here to convey our memory
+ * pressure.
+ */
+
+static void post_status(struct hv_dynmem_device *dm)
+{
+ struct dm_status status;
+ struct sysinfo val;
+ unsigned long now = jiffies;
+ unsigned long last_post = last_post_time;
+
+ if (pressure_report_delay > 0) {
+ --pressure_report_delay;
+ return;
+ }
+
+ if (!time_after(now, (last_post_time + HZ)))
+ return;
+
+ si_meminfo(&val);
+ memset(&status, 0, sizeof(struct dm_status));
+ status.hdr.type = DM_STATUS_REPORT;
+ status.hdr.size = sizeof(struct dm_status);
+ status.hdr.trans_id = atomic_inc_return(&trans_id);
+
+ /*
+ * The host expects the guest to report free and committed memory.
+ * Furthermore, the host expects the pressure information to include
+ * the ballooned out pages. For a given amount of memory that we are
+ * managing we need to compute a floor below which we should not
+ * balloon. Compute this and add it to the pressure report.
+ * We also need to report all offline pages (num_pages_added -
+ * num_pages_onlined) as committed to the host, otherwise it can try
+ * asking us to balloon them out.
+ */
+ status.num_avail = val.freeram;
+ status.num_committed = vm_memory_committed() +
+ dm->num_pages_ballooned +
+ (dm->num_pages_added > dm->num_pages_onlined ?
+ dm->num_pages_added - dm->num_pages_onlined : 0) +
+ compute_balloon_floor();
+
+ /*
+ * If our transaction ID is no longer current, just don't
+ * send the status. This can happen if we were interrupted
+ * after we picked our transaction ID.
+ */
+ if (status.hdr.trans_id != atomic_read(&trans_id))
+ return;
+
+ /*
+ * If the last post time that we sampled has changed,
+ * we have raced, don't post the status.
+ */
+ if (last_post != last_post_time)
+ return;
+
+ last_post_time = jiffies;
+ vmbus_sendpacket(dm->dev->channel, &status,
+ sizeof(struct dm_status),
+ (unsigned long)NULL,
+ VM_PKT_DATA_INBAND, 0);
+
+}
+
+static void free_balloon_pages(struct hv_dynmem_device *dm,
+ union dm_mem_page_range *range_array)
+{
+ int num_pages = range_array->finfo.page_cnt;
+ __u64 start_frame = range_array->finfo.start_page;
+ struct page *pg;
+ int i;
+
+ for (i = 0; i < num_pages; i++) {
+ pg = pfn_to_page(i + start_frame);
+ __free_page(pg);
+ dm->num_pages_ballooned--;
+ }
+}
+
+
+
+static unsigned int alloc_balloon_pages(struct hv_dynmem_device *dm,
+ unsigned int num_pages,
+ struct dm_balloon_response *bl_resp,
+ int alloc_unit)
+{
+ unsigned int i = 0;
+ struct page *pg;
+
+ if (num_pages < alloc_unit)
+ return 0;
+
+ for (i = 0; (i * alloc_unit) < num_pages; i++) {
+ if (bl_resp->hdr.size + sizeof(union dm_mem_page_range) >
+ PAGE_SIZE)
+ return i * alloc_unit;
+
+ /*
+ * We execute this code in a thread context. Furthermore,
+ * we don't want the kernel to try too hard.
+ */
+ pg = alloc_pages(GFP_HIGHUSER | __GFP_NORETRY |
+ __GFP_NOMEMALLOC | __GFP_NOWARN,
+ get_order(alloc_unit << PAGE_SHIFT));
+
+ if (!pg)
+ return i * alloc_unit;
+
+ dm->num_pages_ballooned += alloc_unit;
+
+ /*
+ * If we allocatted 2M pages; split them so we
+ * can free them in any order we get.
+ */
+
+ if (alloc_unit != 1)
+ split_page(pg, get_order(alloc_unit << PAGE_SHIFT));
+
+ bl_resp->range_count++;
+ bl_resp->range_array[i].finfo.start_page =
+ page_to_pfn(pg);
+ bl_resp->range_array[i].finfo.page_cnt = alloc_unit;
+ bl_resp->hdr.size += sizeof(union dm_mem_page_range);
+
+ }
+
+ return num_pages;
+}
+
+
+
+static void balloon_up(struct work_struct *dummy)
+{
+ unsigned int num_pages = dm_device.balloon_wrk.num_pages;
+ unsigned int num_ballooned = 0;
+ struct dm_balloon_response *bl_resp;
+ int alloc_unit;
+ int ret;
+ bool done = false;
+ int i;
+ struct sysinfo val;
+ unsigned long floor;
+
+ /* The host balloons pages in 2M granularity. */
+ WARN_ON_ONCE(num_pages % PAGES_IN_2M != 0);
+
+ /*
+ * We will attempt 2M allocations. However, if we fail to
+ * allocate 2M chunks, we will go back to 4k allocations.
+ */
+ alloc_unit = 512;
+
+ si_meminfo(&val);
+ floor = compute_balloon_floor();
+
+ /* Refuse to balloon below the floor, keep the 2M granularity. */
+ if (val.freeram < num_pages || val.freeram - num_pages < floor) {
+ num_pages = val.freeram > floor ? (val.freeram - floor) : 0;
+ num_pages -= num_pages % PAGES_IN_2M;
+ }
+
+ while (!done) {
+ bl_resp = (struct dm_balloon_response *)send_buffer;
+ memset(send_buffer, 0, PAGE_SIZE);
+ bl_resp->hdr.type = DM_BALLOON_RESPONSE;
+ bl_resp->hdr.size = sizeof(struct dm_balloon_response);
+ bl_resp->more_pages = 1;
+
+
+ num_pages -= num_ballooned;
+ num_ballooned = alloc_balloon_pages(&dm_device, num_pages,
+ bl_resp, alloc_unit);
+
+ if (alloc_unit != 1 && num_ballooned == 0) {
+ alloc_unit = 1;
+ continue;
+ }
+
+ if (num_ballooned == 0 || num_ballooned == num_pages) {
+ bl_resp->more_pages = 0;
+ done = true;
+ dm_device.state = DM_INITIALIZED;
+ }
+
+ /*
+ * We are pushing a lot of data through the channel;
+ * deal with transient failures caused because of the
+ * lack of space in the ring buffer.
+ */
+
+ do {
+ bl_resp->hdr.trans_id = atomic_inc_return(&trans_id);
+ ret = vmbus_sendpacket(dm_device.dev->channel,
+ bl_resp,
+ bl_resp->hdr.size,
+ (unsigned long)NULL,
+ VM_PKT_DATA_INBAND, 0);
+
+ if (ret == -EAGAIN)
+ msleep(20);
+ post_status(&dm_device);
+ } while (ret == -EAGAIN);
+
+ if (ret) {
+ /*
+ * Free up the memory we allocatted.
+ */
+ pr_info("Balloon response failed\n");
+
+ for (i = 0; i < bl_resp->range_count; i++)
+ free_balloon_pages(&dm_device,
+ &bl_resp->range_array[i]);
+
+ done = true;
+ }
+ }
+
+}
+
+static void balloon_down(struct hv_dynmem_device *dm,
+ struct dm_unballoon_request *req)
+{
+ union dm_mem_page_range *range_array = req->range_array;
+ int range_count = req->range_count;
+ struct dm_unballoon_response resp;
+ int i;
+
+ for (i = 0; i < range_count; i++) {
+ free_balloon_pages(dm, &range_array[i]);
+ complete(&dm_device.config_event);
+ }
+
+ if (req->more_pages == 1)
+ return;
+
+ memset(&resp, 0, sizeof(struct dm_unballoon_response));
+ resp.hdr.type = DM_UNBALLOON_RESPONSE;
+ resp.hdr.trans_id = atomic_inc_return(&trans_id);
+ resp.hdr.size = sizeof(struct dm_unballoon_response);
+
+ vmbus_sendpacket(dm_device.dev->channel, &resp,
+ sizeof(struct dm_unballoon_response),
+ (unsigned long)NULL,
+ VM_PKT_DATA_INBAND, 0);
+
+ dm->state = DM_INITIALIZED;
+}
+
+static void balloon_onchannelcallback(void *context);
+
+static int dm_thread_func(void *dm_dev)
+{
+ struct hv_dynmem_device *dm = dm_dev;
+
+ while (!kthread_should_stop()) {
+ wait_for_completion_interruptible_timeout(
+ &dm_device.config_event, 1*HZ);
+ /*
+ * The host expects us to post information on the memory
+ * pressure every second.
+ */
+ reinit_completion(&dm_device.config_event);
+ post_status(dm);
+ }
+
+ return 0;
+}
+
+
+static void version_resp(struct hv_dynmem_device *dm,
+ struct dm_version_response *vresp)
+{
+ struct dm_version_request version_req;
+ int ret;
+
+ if (vresp->is_accepted) {
+ /*
+ * We are done; wakeup the
+ * context waiting for version
+ * negotiation.
+ */
+ complete(&dm->host_event);
+ return;
+ }
+ /*
+ * If there are more versions to try, continue
+ * with negotiations; if not
+ * shutdown the service since we are not able
+ * to negotiate a suitable version number
+ * with the host.
+ */
+ if (dm->next_version == 0)
+ goto version_error;
+
+ dm->next_version = 0;
+ memset(&version_req, 0, sizeof(struct dm_version_request));
+ version_req.hdr.type = DM_VERSION_REQUEST;
+ version_req.hdr.size = sizeof(struct dm_version_request);
+ version_req.hdr.trans_id = atomic_inc_return(&trans_id);
+ version_req.version.version = DYNMEM_PROTOCOL_VERSION_WIN7;
+ version_req.is_last_attempt = 1;
+
+ ret = vmbus_sendpacket(dm->dev->channel, &version_req,
+ sizeof(struct dm_version_request),
+ (unsigned long)NULL,
+ VM_PKT_DATA_INBAND, 0);
+
+ if (ret)
+ goto version_error;
+
+ return;
+
+version_error:
+ dm->state = DM_INIT_ERROR;
+ complete(&dm->host_event);
+}
+
+static void cap_resp(struct hv_dynmem_device *dm,
+ struct dm_capabilities_resp_msg *cap_resp)
+{
+ if (!cap_resp->is_accepted) {
+ pr_info("Capabilities not accepted by host\n");
+ dm->state = DM_INIT_ERROR;
+ }
+ complete(&dm->host_event);
+}
+
+static void balloon_onchannelcallback(void *context)
+{
+ struct hv_device *dev = context;
+ u32 recvlen;
+ u64 requestid;
+ struct dm_message *dm_msg;
+ struct dm_header *dm_hdr;
+ struct hv_dynmem_device *dm = hv_get_drvdata(dev);
+ struct dm_balloon *bal_msg;
+ struct dm_hot_add *ha_msg;
+ union dm_mem_page_range *ha_pg_range;
+ union dm_mem_page_range *ha_region;
+
+ memset(recv_buffer, 0, sizeof(recv_buffer));
+ vmbus_recvpacket(dev->channel, recv_buffer,
+ PAGE_SIZE, &recvlen, &requestid);
+
+ if (recvlen > 0) {
+ dm_msg = (struct dm_message *)recv_buffer;
+ dm_hdr = &dm_msg->hdr;
+
+ switch (dm_hdr->type) {
+ case DM_VERSION_RESPONSE:
+ version_resp(dm,
+ (struct dm_version_response *)dm_msg);
+ break;
+
+ case DM_CAPABILITIES_RESPONSE:
+ cap_resp(dm,
+ (struct dm_capabilities_resp_msg *)dm_msg);
+ break;
+
+ case DM_BALLOON_REQUEST:
+ if (dm->state == DM_BALLOON_UP)
+ pr_warn("Currently ballooning\n");
+ bal_msg = (struct dm_balloon *)recv_buffer;
+ dm->state = DM_BALLOON_UP;
+ dm_device.balloon_wrk.num_pages = bal_msg->num_pages;
+ schedule_work(&dm_device.balloon_wrk.wrk);
+ break;
+
+ case DM_UNBALLOON_REQUEST:
+ dm->state = DM_BALLOON_DOWN;
+ balloon_down(dm,
+ (struct dm_unballoon_request *)recv_buffer);
+ break;
+
+ case DM_MEM_HOT_ADD_REQUEST:
+ if (dm->state == DM_HOT_ADD)
+ pr_warn("Currently hot-adding\n");
+ dm->state = DM_HOT_ADD;
+ ha_msg = (struct dm_hot_add *)recv_buffer;
+ if (ha_msg->hdr.size == sizeof(struct dm_hot_add)) {
+ /*
+ * This is a normal hot-add request specifying
+ * hot-add memory.
+ */
+ ha_pg_range = &ha_msg->range;
+ dm->ha_wrk.ha_page_range = *ha_pg_range;
+ dm->ha_wrk.ha_region_range.page_range = 0;
+ } else {
+ /*
+ * Host is specifying that we first hot-add
+ * a region and then partially populate this
+ * region.
+ */
+ dm->host_specified_ha_region = true;
+ ha_pg_range = &ha_msg->range;
+ ha_region = &ha_pg_range[1];
+ dm->ha_wrk.ha_page_range = *ha_pg_range;
+ dm->ha_wrk.ha_region_range = *ha_region;
+ }
+ schedule_work(&dm_device.ha_wrk.wrk);
+ break;
+
+ case DM_INFO_MESSAGE:
+ process_info(dm, (struct dm_info_msg *)dm_msg);
+ break;
+
+ default:
+ pr_err("Unhandled message: type: %d\n", dm_hdr->type);
+
+ }
+ }
+
+}
+
+static int balloon_probe(struct hv_device *dev,
+ const struct hv_vmbus_device_id *dev_id)
+{
+ int ret;
+ unsigned long t;
+ struct dm_version_request version_req;
+ struct dm_capabilities cap_msg;
+
+ do_hot_add = hot_add;
+
+ /*
+ * First allocate a send buffer.
+ */
+
+ send_buffer = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!send_buffer)
+ return -ENOMEM;
+
+ ret = vmbus_open(dev->channel, dm_ring_size, dm_ring_size, NULL, 0,
+ balloon_onchannelcallback, dev);
+
+ if (ret)
+ goto probe_error0;
+
+ dm_device.dev = dev;
+ dm_device.state = DM_INITIALIZING;
+ dm_device.next_version = DYNMEM_PROTOCOL_VERSION_WIN7;
+ init_completion(&dm_device.host_event);
+ init_completion(&dm_device.config_event);
+ INIT_LIST_HEAD(&dm_device.ha_region_list);
+ mutex_init(&dm_device.ha_region_mutex);
+ INIT_WORK(&dm_device.balloon_wrk.wrk, balloon_up);
+ INIT_WORK(&dm_device.ha_wrk.wrk, hot_add_req);
+ dm_device.host_specified_ha_region = false;
+
+ dm_device.thread =
+ kthread_run(dm_thread_func, &dm_device, "hv_balloon");
+ if (IS_ERR(dm_device.thread)) {
+ ret = PTR_ERR(dm_device.thread);
+ goto probe_error1;
+ }
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+ set_online_page_callback(&hv_online_page);
+ register_memory_notifier(&hv_memory_nb);
+#endif
+
+ hv_set_drvdata(dev, &dm_device);
+ /*
+ * Initiate the hand shake with the host and negotiate
+ * a version that the host can support. We start with the
+ * highest version number and go down if the host cannot
+ * support it.
+ */
+ memset(&version_req, 0, sizeof(struct dm_version_request));
+ version_req.hdr.type = DM_VERSION_REQUEST;
+ version_req.hdr.size = sizeof(struct dm_version_request);
+ version_req.hdr.trans_id = atomic_inc_return(&trans_id);
+ version_req.version.version = DYNMEM_PROTOCOL_VERSION_WIN8;
+ version_req.is_last_attempt = 0;
+
+ ret = vmbus_sendpacket(dev->channel, &version_req,
+ sizeof(struct dm_version_request),
+ (unsigned long)NULL,
+ VM_PKT_DATA_INBAND, 0);
+ if (ret)
+ goto probe_error2;
+
+ t = wait_for_completion_timeout(&dm_device.host_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto probe_error2;
+ }
+
+ /*
+ * If we could not negotiate a compatible version with the host
+ * fail the probe function.
+ */
+ if (dm_device.state == DM_INIT_ERROR) {
+ ret = -ETIMEDOUT;
+ goto probe_error2;
+ }
+ /*
+ * Now submit our capabilities to the host.
+ */
+ memset(&cap_msg, 0, sizeof(struct dm_capabilities));
+ cap_msg.hdr.type = DM_CAPABILITIES_REPORT;
+ cap_msg.hdr.size = sizeof(struct dm_capabilities);
+ cap_msg.hdr.trans_id = atomic_inc_return(&trans_id);
+
+ cap_msg.caps.cap_bits.balloon = 1;
+ cap_msg.caps.cap_bits.hot_add = 1;
+
+ /*
+ * Specify our alignment requirements as it relates
+ * memory hot-add. Specify 128MB alignment.
+ */
+ cap_msg.caps.cap_bits.hot_add_alignment = 7;
+
+ /*
+ * Currently the host does not use these
+ * values and we set them to what is done in the
+ * Windows driver.
+ */
+ cap_msg.min_page_cnt = 0;
+ cap_msg.max_page_number = -1;
+
+ ret = vmbus_sendpacket(dev->channel, &cap_msg,
+ sizeof(struct dm_capabilities),
+ (unsigned long)NULL,
+ VM_PKT_DATA_INBAND, 0);
+ if (ret)
+ goto probe_error2;
+
+ t = wait_for_completion_timeout(&dm_device.host_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto probe_error2;
+ }
+
+ /*
+ * If the host does not like our capabilities,
+ * fail the probe function.
+ */
+ if (dm_device.state == DM_INIT_ERROR) {
+ ret = -ETIMEDOUT;
+ goto probe_error2;
+ }
+
+ dm_device.state = DM_INITIALIZED;
+
+ return 0;
+
+probe_error2:
+#ifdef CONFIG_MEMORY_HOTPLUG
+ restore_online_page_callback(&hv_online_page);
+#endif
+ kthread_stop(dm_device.thread);
+
+probe_error1:
+ vmbus_close(dev->channel);
+probe_error0:
+ kfree(send_buffer);
+ return ret;
+}
+
+static int balloon_remove(struct hv_device *dev)
+{
+ struct hv_dynmem_device *dm = hv_get_drvdata(dev);
+ struct list_head *cur, *tmp;
+ struct hv_hotadd_state *has;
+
+ if (dm->num_pages_ballooned != 0)
+ pr_warn("Ballooned pages: %d\n", dm->num_pages_ballooned);
+
+ cancel_work_sync(&dm->balloon_wrk.wrk);
+ cancel_work_sync(&dm->ha_wrk.wrk);
+
+ vmbus_close(dev->channel);
+ kthread_stop(dm->thread);
+ kfree(send_buffer);
+#ifdef CONFIG_MEMORY_HOTPLUG
+ restore_online_page_callback(&hv_online_page);
+ unregister_memory_notifier(&hv_memory_nb);
+#endif
+ list_for_each_safe(cur, tmp, &dm->ha_region_list) {
+ has = list_entry(cur, struct hv_hotadd_state, list);
+ list_del(&has->list);
+ kfree(has);
+ }
+
+ return 0;
+}
+
+static const struct hv_vmbus_device_id id_table[] = {
+ /* Dynamic Memory Class ID */
+ /* 525074DC-8985-46e2-8057-A307DC18A502 */
+ { HV_DM_GUID, },
+ { },
+};
+
+MODULE_DEVICE_TABLE(vmbus, id_table);
+
+static struct hv_driver balloon_drv = {
+ .name = "hv_balloon",
+ .id_table = id_table,
+ .probe = balloon_probe,
+ .remove = balloon_remove,
+};
+
+static int __init init_balloon_drv(void)
+{
+
+ return vmbus_driver_register(&balloon_drv);
+}
+
+module_init(init_balloon_drv);
+
+MODULE_DESCRIPTION("Hyper-V Balloon");
+MODULE_LICENSE("GPL");
diff --git a/drivers/hv/hv_fcopy.c b/drivers/hv/hv_fcopy.c
new file mode 100644
index 000000000..cd453e4b2
--- /dev/null
+++ b/drivers/hv/hv_fcopy.c
@@ -0,0 +1,441 @@
+/*
+ * An implementation of file copy service.
+ *
+ * Copyright (C) 2014, Microsoft, Inc.
+ *
+ * Author : K. Y. Srinivasan <ksrinivasan@novell.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for more
+ * details.
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/semaphore.h>
+#include <linux/fs.h>
+#include <linux/nls.h>
+#include <linux/workqueue.h>
+#include <linux/cdev.h>
+#include <linux/hyperv.h>
+#include <linux/sched.h>
+#include <linux/uaccess.h>
+#include <linux/miscdevice.h>
+
+#include "hyperv_vmbus.h"
+
+#define WIN8_SRV_MAJOR 1
+#define WIN8_SRV_MINOR 1
+#define WIN8_SRV_VERSION (WIN8_SRV_MAJOR << 16 | WIN8_SRV_MINOR)
+
+/*
+ * Global state maintained for transaction that is being processed.
+ * For a class of integration services, including the "file copy service",
+ * the specified protocol is a "request/response" protocol which means that
+ * there can only be single outstanding transaction from the host at any
+ * given point in time. We use this to simplify memory management in this
+ * driver - we cache and process only one message at a time.
+ *
+ * While the request/response protocol is guaranteed by the host, we further
+ * ensure this by serializing packet processing in this driver - we do not
+ * read additional packets from the VMBUs until the current packet is fully
+ * handled.
+ *
+ * The transaction "active" state is set when we receive a request from the
+ * host and we cleanup this state when the transaction is completed - when we
+ * respond to the host with our response. When the transaction active state is
+ * set, we defer handling incoming packets.
+ */
+
+static struct {
+ bool active; /* transaction status - active or not */
+ int recv_len; /* number of bytes received. */
+ struct hv_fcopy_hdr *fcopy_msg; /* current message */
+ struct hv_start_fcopy message; /* sent to daemon */
+ struct vmbus_channel *recv_channel; /* chn we got the request */
+ u64 recv_req_id; /* request ID. */
+ void *fcopy_context; /* for the channel callback */
+ struct semaphore read_sema;
+} fcopy_transaction;
+
+static bool opened; /* currently device opened */
+
+/*
+ * Before we can accept copy messages from the host, we need
+ * to handshake with the user level daemon. This state tracks
+ * if we are in the handshake phase.
+ */
+static bool in_hand_shake = true;
+static void fcopy_send_data(void);
+static void fcopy_respond_to_host(int error);
+static void fcopy_work_func(struct work_struct *dummy);
+static DECLARE_DELAYED_WORK(fcopy_work, fcopy_work_func);
+static u8 *recv_buffer;
+
+static void fcopy_work_func(struct work_struct *dummy)
+{
+ /*
+ * If the timer fires, the user-mode component has not responded;
+ * process the pending transaction.
+ */
+ fcopy_respond_to_host(HV_E_FAIL);
+
+ /* In the case the user-space daemon crashes, hangs or is killed, we
+ * need to down the semaphore, otherwise, after the daemon starts next
+ * time, the obsolete data in fcopy_transaction.message or
+ * fcopy_transaction.fcopy_msg will be used immediately.
+ *
+ * NOTE: fcopy_read() happens to get the semaphore (very rare)? We're
+ * still OK, because we've reported the failure to the host.
+ */
+ if (down_trylock(&fcopy_transaction.read_sema))
+ ;
+
+}
+
+static int fcopy_handle_handshake(u32 version)
+{
+ switch (version) {
+ case FCOPY_CURRENT_VERSION:
+ break;
+ default:
+ /*
+ * For now we will fail the registration.
+ * If and when we have multiple versions to
+ * deal with, we will be backward compatible.
+ * We will add this code when needed.
+ */
+ return -EINVAL;
+ }
+ pr_info("FCP: user-mode registering done. Daemon version: %d\n",
+ version);
+ fcopy_transaction.active = false;
+ if (fcopy_transaction.fcopy_context)
+ hv_fcopy_onchannelcallback(fcopy_transaction.fcopy_context);
+ in_hand_shake = false;
+ return 0;
+}
+
+static void fcopy_send_data(void)
+{
+ struct hv_start_fcopy *smsg_out = &fcopy_transaction.message;
+ int operation = fcopy_transaction.fcopy_msg->operation;
+ struct hv_start_fcopy *smsg_in;
+
+ /*
+ * The strings sent from the host are encoded in
+ * in utf16; convert it to utf8 strings.
+ * The host assures us that the utf16 strings will not exceed
+ * the max lengths specified. We will however, reserve room
+ * for the string terminating character - in the utf16s_utf8s()
+ * function we limit the size of the buffer where the converted
+ * string is placed to W_MAX_PATH -1 to guarantee
+ * that the strings can be properly terminated!
+ */
+
+ switch (operation) {
+ case START_FILE_COPY:
+ memset(smsg_out, 0, sizeof(struct hv_start_fcopy));
+ smsg_out->hdr.operation = operation;
+ smsg_in = (struct hv_start_fcopy *)fcopy_transaction.fcopy_msg;
+
+ utf16s_to_utf8s((wchar_t *)smsg_in->file_name, W_MAX_PATH,
+ UTF16_LITTLE_ENDIAN,
+ (__u8 *)smsg_out->file_name, W_MAX_PATH - 1);
+
+ utf16s_to_utf8s((wchar_t *)smsg_in->path_name, W_MAX_PATH,
+ UTF16_LITTLE_ENDIAN,
+ (__u8 *)smsg_out->path_name, W_MAX_PATH - 1);
+
+ smsg_out->copy_flags = smsg_in->copy_flags;
+ smsg_out->file_size = smsg_in->file_size;
+ break;
+
+ default:
+ break;
+ }
+ up(&fcopy_transaction.read_sema);
+ return;
+}
+
+/*
+ * Send a response back to the host.
+ */
+
+static void
+fcopy_respond_to_host(int error)
+{
+ struct icmsg_hdr *icmsghdr;
+ u32 buf_len;
+ struct vmbus_channel *channel;
+ u64 req_id;
+
+ /*
+ * Copy the global state for completing the transaction. Note that
+ * only one transaction can be active at a time. This is guaranteed
+ * by the file copy protocol implemented by the host. Furthermore,
+ * the "transaction active" state we maintain ensures that there can
+ * only be one active transaction at a time.
+ */
+
+ buf_len = fcopy_transaction.recv_len;
+ channel = fcopy_transaction.recv_channel;
+ req_id = fcopy_transaction.recv_req_id;
+
+ fcopy_transaction.active = false;
+
+ icmsghdr = (struct icmsg_hdr *)
+ &recv_buffer[sizeof(struct vmbuspipe_hdr)];
+
+ if (channel->onchannel_callback == NULL)
+ /*
+ * We have raced with util driver being unloaded;
+ * silently return.
+ */
+ return;
+
+ icmsghdr->status = error;
+ icmsghdr->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;
+ vmbus_sendpacket(channel, recv_buffer, buf_len, req_id,
+ VM_PKT_DATA_INBAND, 0);
+}
+
+void hv_fcopy_onchannelcallback(void *context)
+{
+ struct vmbus_channel *channel = context;
+ u32 recvlen;
+ u64 requestid;
+ struct hv_fcopy_hdr *fcopy_msg;
+ struct icmsg_hdr *icmsghdr;
+ struct icmsg_negotiate *negop = NULL;
+ int util_fw_version;
+ int fcopy_srv_version;
+
+ if (fcopy_transaction.active) {
+ /*
+ * We will defer processing this callback once
+ * the current transaction is complete.
+ */
+ fcopy_transaction.fcopy_context = context;
+ return;
+ }
+
+ vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 2, &recvlen,
+ &requestid);
+ if (recvlen <= 0)
+ return;
+
+ icmsghdr = (struct icmsg_hdr *)&recv_buffer[
+ sizeof(struct vmbuspipe_hdr)];
+ if (icmsghdr->icmsgtype == ICMSGTYPE_NEGOTIATE) {
+ util_fw_version = UTIL_FW_VERSION;
+ fcopy_srv_version = WIN8_SRV_VERSION;
+ vmbus_prep_negotiate_resp(icmsghdr, negop, recv_buffer,
+ util_fw_version, fcopy_srv_version);
+ } else {
+ fcopy_msg = (struct hv_fcopy_hdr *)&recv_buffer[
+ sizeof(struct vmbuspipe_hdr) +
+ sizeof(struct icmsg_hdr)];
+
+ /*
+ * Stash away this global state for completing the
+ * transaction; note transactions are serialized.
+ */
+
+ fcopy_transaction.active = true;
+ fcopy_transaction.recv_len = recvlen;
+ fcopy_transaction.recv_channel = channel;
+ fcopy_transaction.recv_req_id = requestid;
+ fcopy_transaction.fcopy_msg = fcopy_msg;
+
+ /*
+ * Send the information to the user-level daemon.
+ */
+ schedule_delayed_work(&fcopy_work, 5*HZ);
+ fcopy_send_data();
+ return;
+ }
+ icmsghdr->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;
+ vmbus_sendpacket(channel, recv_buffer, recvlen, requestid,
+ VM_PKT_DATA_INBAND, 0);
+}
+
+/*
+ * Create a char device that can support read/write for passing
+ * the payload.
+ */
+
+static ssize_t fcopy_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ void *src;
+ size_t copy_size;
+ int operation;
+
+ /*
+ * Wait until there is something to be read.
+ */
+ if (down_interruptible(&fcopy_transaction.read_sema))
+ return -EINTR;
+
+ /*
+ * The channel may be rescinded and in this case, we will wakeup the
+ * the thread blocked on the semaphore and we will use the opened
+ * state to correctly handle this case.
+ */
+ if (!opened)
+ return -ENODEV;
+
+ operation = fcopy_transaction.fcopy_msg->operation;
+
+ if (operation == START_FILE_COPY) {
+ src = &fcopy_transaction.message;
+ copy_size = sizeof(struct hv_start_fcopy);
+ if (count < copy_size)
+ return 0;
+ } else {
+ src = fcopy_transaction.fcopy_msg;
+ copy_size = sizeof(struct hv_do_fcopy);
+ if (count < copy_size)
+ return 0;
+ }
+ if (copy_to_user(buf, src, copy_size))
+ return -EFAULT;
+
+ return copy_size;
+}
+
+static ssize_t fcopy_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ int response = 0;
+
+ if (count != sizeof(int))
+ return -EINVAL;
+
+ if (copy_from_user(&response, buf, sizeof(int)))
+ return -EFAULT;
+
+ if (in_hand_shake) {
+ if (fcopy_handle_handshake(response))
+ return -EINVAL;
+ return sizeof(int);
+ }
+
+ /*
+ * Complete the transaction by forwarding the result
+ * to the host. But first, cancel the timeout.
+ */
+ if (cancel_delayed_work_sync(&fcopy_work))
+ fcopy_respond_to_host(response);
+
+ return sizeof(int);
+}
+
+static int fcopy_open(struct inode *inode, struct file *f)
+{
+ /*
+ * The user level daemon that will open this device is
+ * really an extension of this driver. We can have only
+ * active open at a time.
+ */
+ if (opened)
+ return -EBUSY;
+
+ /*
+ * The daemon is alive; setup the state.
+ */
+ opened = true;
+ return 0;
+}
+
+/* XXX: there are still some tricky corner cases, e.g.,
+ * 1) In a SMP guest, when fcopy_release() runs between
+ * schedule_delayed_work() and fcopy_send_data(), there is
+ * still a chance an obsolete message will be queued.
+ *
+ * 2) When the fcopy daemon is running, if we unload the driver,
+ * we'll notice a kernel oops when we kill the daemon later.
+ */
+static int fcopy_release(struct inode *inode, struct file *f)
+{
+ /*
+ * The daemon has exited; reset the state.
+ */
+ in_hand_shake = true;
+ opened = false;
+
+ if (cancel_delayed_work_sync(&fcopy_work)) {
+ /* We haven't up()-ed the semaphore(very rare)? */
+ if (down_trylock(&fcopy_transaction.read_sema))
+ ;
+ fcopy_respond_to_host(HV_E_FAIL);
+ }
+ return 0;
+}
+
+
+static const struct file_operations fcopy_fops = {
+ .read = fcopy_read,
+ .write = fcopy_write,
+ .release = fcopy_release,
+ .open = fcopy_open,
+};
+
+static struct miscdevice fcopy_misc = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "vmbus/hv_fcopy",
+ .fops = &fcopy_fops,
+};
+
+static int fcopy_dev_init(void)
+{
+ return misc_register(&fcopy_misc);
+}
+
+static void fcopy_dev_deinit(void)
+{
+
+ /*
+ * The device is going away - perhaps because the
+ * host has rescinded the channel. Setup state so that
+ * user level daemon can gracefully exit if it is blocked
+ * on the read semaphore.
+ */
+ opened = false;
+ /*
+ * Signal the semaphore as the device is
+ * going away.
+ */
+ up(&fcopy_transaction.read_sema);
+ misc_deregister(&fcopy_misc);
+}
+
+int hv_fcopy_init(struct hv_util_service *srv)
+{
+ recv_buffer = srv->recv_buffer;
+
+ /*
+ * When this driver loads, the user level daemon that
+ * processes the host requests may not yet be running.
+ * Defer processing channel callbacks until the daemon
+ * has registered.
+ */
+ fcopy_transaction.active = true;
+ sema_init(&fcopy_transaction.read_sema, 0);
+
+ return fcopy_dev_init();
+}
+
+void hv_fcopy_deinit(void)
+{
+ cancel_delayed_work_sync(&fcopy_work);
+ fcopy_dev_deinit();
+}
diff --git a/drivers/hv/hv_kvp.c b/drivers/hv/hv_kvp.c
new file mode 100644
index 000000000..beb8105c0
--- /dev/null
+++ b/drivers/hv/hv_kvp.c
@@ -0,0 +1,722 @@
+/*
+ * An implementation of key value pair (KVP) functionality for Linux.
+ *
+ *
+ * Copyright (C) 2010, Novell, Inc.
+ * Author : K. Y. Srinivasan <ksrinivasan@novell.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/net.h>
+#include <linux/nls.h>
+#include <linux/connector.h>
+#include <linux/workqueue.h>
+#include <linux/hyperv.h>
+
+
+/*
+ * Pre win8 version numbers used in ws2008 and ws 2008 r2 (win7)
+ */
+#define WS2008_SRV_MAJOR 1
+#define WS2008_SRV_MINOR 0
+#define WS2008_SRV_VERSION (WS2008_SRV_MAJOR << 16 | WS2008_SRV_MINOR)
+
+#define WIN7_SRV_MAJOR 3
+#define WIN7_SRV_MINOR 0
+#define WIN7_SRV_VERSION (WIN7_SRV_MAJOR << 16 | WIN7_SRV_MINOR)
+
+#define WIN8_SRV_MAJOR 4
+#define WIN8_SRV_MINOR 0
+#define WIN8_SRV_VERSION (WIN8_SRV_MAJOR << 16 | WIN8_SRV_MINOR)
+
+/*
+ * Global state maintained for transaction that is being processed.
+ * Note that only one transaction can be active at any point in time.
+ *
+ * This state is set when we receive a request from the host; we
+ * cleanup this state when the transaction is completed - when we respond
+ * to the host with the key value.
+ */
+
+static struct {
+ bool active; /* transaction status - active or not */
+ int recv_len; /* number of bytes received. */
+ struct hv_kvp_msg *kvp_msg; /* current message */
+ struct vmbus_channel *recv_channel; /* chn we got the request */
+ u64 recv_req_id; /* request ID. */
+ void *kvp_context; /* for the channel callback */
+} kvp_transaction;
+
+/*
+ * Before we can accept KVP messages from the host, we need
+ * to handshake with the user level daemon. This state tracks
+ * if we are in the handshake phase.
+ */
+static bool in_hand_shake = true;
+
+/*
+ * This state maintains the version number registered by the daemon.
+ */
+static int dm_reg_value;
+
+static void kvp_send_key(struct work_struct *dummy);
+
+
+static void kvp_respond_to_host(struct hv_kvp_msg *msg, int error);
+static void kvp_work_func(struct work_struct *dummy);
+static void kvp_register(int);
+
+static DECLARE_DELAYED_WORK(kvp_work, kvp_work_func);
+static DECLARE_WORK(kvp_sendkey_work, kvp_send_key);
+
+static struct cb_id kvp_id = { CN_KVP_IDX, CN_KVP_VAL };
+static const char kvp_name[] = "kvp_kernel_module";
+static u8 *recv_buffer;
+/*
+ * Register the kernel component with the user-level daemon.
+ * As part of this registration, pass the LIC version number.
+ * This number has no meaning, it satisfies the registration protocol.
+ */
+#define HV_DRV_VERSION "3.1"
+
+static void
+kvp_register(int reg_value)
+{
+
+ struct cn_msg *msg;
+ struct hv_kvp_msg *kvp_msg;
+ char *version;
+
+ msg = kzalloc(sizeof(*msg) + sizeof(struct hv_kvp_msg), GFP_ATOMIC);
+
+ if (msg) {
+ kvp_msg = (struct hv_kvp_msg *)msg->data;
+ version = kvp_msg->body.kvp_register.version;
+ msg->id.idx = CN_KVP_IDX;
+ msg->id.val = CN_KVP_VAL;
+
+ kvp_msg->kvp_hdr.operation = reg_value;
+ strcpy(version, HV_DRV_VERSION);
+ msg->len = sizeof(struct hv_kvp_msg);
+ cn_netlink_send(msg, 0, 0, GFP_ATOMIC);
+ kfree(msg);
+ }
+}
+static void
+kvp_work_func(struct work_struct *dummy)
+{
+ /*
+ * If the timer fires, the user-mode component has not responded;
+ * process the pending transaction.
+ */
+ kvp_respond_to_host(NULL, HV_E_FAIL);
+}
+
+static void poll_channel(struct vmbus_channel *channel)
+{
+ if (channel->target_cpu != smp_processor_id())
+ smp_call_function_single(channel->target_cpu,
+ hv_kvp_onchannelcallback,
+ channel, true);
+ else
+ hv_kvp_onchannelcallback(channel);
+}
+
+
+static int kvp_handle_handshake(struct hv_kvp_msg *msg)
+{
+ int ret = 1;
+
+ switch (msg->kvp_hdr.operation) {
+ case KVP_OP_REGISTER:
+ dm_reg_value = KVP_OP_REGISTER;
+ pr_info("KVP: IP injection functionality not available\n");
+ pr_info("KVP: Upgrade the KVP daemon\n");
+ break;
+ case KVP_OP_REGISTER1:
+ dm_reg_value = KVP_OP_REGISTER1;
+ break;
+ default:
+ pr_info("KVP: incompatible daemon\n");
+ pr_info("KVP: KVP version: %d, Daemon version: %d\n",
+ KVP_OP_REGISTER1, msg->kvp_hdr.operation);
+ ret = 0;
+ }
+
+ if (ret) {
+ /*
+ * We have a compatible daemon; complete the handshake.
+ */
+ pr_info("KVP: user-mode registering done.\n");
+ kvp_register(dm_reg_value);
+ kvp_transaction.active = false;
+ if (kvp_transaction.kvp_context)
+ poll_channel(kvp_transaction.kvp_context);
+ }
+ return ret;
+}
+
+
+/*
+ * Callback when data is received from user mode.
+ */
+
+static void
+kvp_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
+{
+ struct hv_kvp_msg *message;
+ struct hv_kvp_msg_enumerate *data;
+ int error = 0;
+
+ message = (struct hv_kvp_msg *)msg->data;
+
+ /*
+ * If we are negotiating the version information
+ * with the daemon; handle that first.
+ */
+
+ if (in_hand_shake) {
+ if (kvp_handle_handshake(message))
+ in_hand_shake = false;
+ return;
+ }
+
+ /*
+ * Based on the version of the daemon, we propagate errors from the
+ * daemon differently.
+ */
+
+ data = &message->body.kvp_enum_data;
+
+ switch (dm_reg_value) {
+ case KVP_OP_REGISTER:
+ /*
+ * Null string is used to pass back error condition.
+ */
+ if (data->data.key[0] == 0)
+ error = HV_S_CONT;
+ break;
+
+ case KVP_OP_REGISTER1:
+ /*
+ * We use the message header information from
+ * the user level daemon to transmit errors.
+ */
+ error = message->error;
+ break;
+ }
+
+ /*
+ * Complete the transaction by forwarding the key value
+ * to the host. But first, cancel the timeout.
+ */
+ if (cancel_delayed_work_sync(&kvp_work))
+ kvp_respond_to_host(message, error);
+}
+
+
+static int process_ob_ipinfo(void *in_msg, void *out_msg, int op)
+{
+ struct hv_kvp_msg *in = in_msg;
+ struct hv_kvp_ip_msg *out = out_msg;
+ int len;
+
+ switch (op) {
+ case KVP_OP_GET_IP_INFO:
+ /*
+ * Transform all parameters into utf16 encoding.
+ */
+ len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.ip_addr,
+ strlen((char *)in->body.kvp_ip_val.ip_addr),
+ UTF16_HOST_ENDIAN,
+ (wchar_t *)out->kvp_ip_val.ip_addr,
+ MAX_IP_ADDR_SIZE);
+ if (len < 0)
+ return len;
+
+ len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.sub_net,
+ strlen((char *)in->body.kvp_ip_val.sub_net),
+ UTF16_HOST_ENDIAN,
+ (wchar_t *)out->kvp_ip_val.sub_net,
+ MAX_IP_ADDR_SIZE);
+ if (len < 0)
+ return len;
+
+ len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.gate_way,
+ strlen((char *)in->body.kvp_ip_val.gate_way),
+ UTF16_HOST_ENDIAN,
+ (wchar_t *)out->kvp_ip_val.gate_way,
+ MAX_GATEWAY_SIZE);
+ if (len < 0)
+ return len;
+
+ len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.dns_addr,
+ strlen((char *)in->body.kvp_ip_val.dns_addr),
+ UTF16_HOST_ENDIAN,
+ (wchar_t *)out->kvp_ip_val.dns_addr,
+ MAX_IP_ADDR_SIZE);
+ if (len < 0)
+ return len;
+
+ len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.adapter_id,
+ strlen((char *)in->body.kvp_ip_val.adapter_id),
+ UTF16_HOST_ENDIAN,
+ (wchar_t *)out->kvp_ip_val.adapter_id,
+ MAX_IP_ADDR_SIZE);
+ if (len < 0)
+ return len;
+
+ out->kvp_ip_val.dhcp_enabled =
+ in->body.kvp_ip_val.dhcp_enabled;
+ out->kvp_ip_val.addr_family =
+ in->body.kvp_ip_val.addr_family;
+ }
+
+ return 0;
+}
+
+static void process_ib_ipinfo(void *in_msg, void *out_msg, int op)
+{
+ struct hv_kvp_ip_msg *in = in_msg;
+ struct hv_kvp_msg *out = out_msg;
+
+ switch (op) {
+ case KVP_OP_SET_IP_INFO:
+ /*
+ * Transform all parameters into utf8 encoding.
+ */
+ utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.ip_addr,
+ MAX_IP_ADDR_SIZE,
+ UTF16_LITTLE_ENDIAN,
+ (__u8 *)out->body.kvp_ip_val.ip_addr,
+ MAX_IP_ADDR_SIZE);
+
+ utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.sub_net,
+ MAX_IP_ADDR_SIZE,
+ UTF16_LITTLE_ENDIAN,
+ (__u8 *)out->body.kvp_ip_val.sub_net,
+ MAX_IP_ADDR_SIZE);
+
+ utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.gate_way,
+ MAX_GATEWAY_SIZE,
+ UTF16_LITTLE_ENDIAN,
+ (__u8 *)out->body.kvp_ip_val.gate_way,
+ MAX_GATEWAY_SIZE);
+
+ utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.dns_addr,
+ MAX_IP_ADDR_SIZE,
+ UTF16_LITTLE_ENDIAN,
+ (__u8 *)out->body.kvp_ip_val.dns_addr,
+ MAX_IP_ADDR_SIZE);
+
+ out->body.kvp_ip_val.dhcp_enabled = in->kvp_ip_val.dhcp_enabled;
+
+ default:
+ utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.adapter_id,
+ MAX_ADAPTER_ID_SIZE,
+ UTF16_LITTLE_ENDIAN,
+ (__u8 *)out->body.kvp_ip_val.adapter_id,
+ MAX_ADAPTER_ID_SIZE);
+
+ out->body.kvp_ip_val.addr_family = in->kvp_ip_val.addr_family;
+ }
+}
+
+
+
+
+static void
+kvp_send_key(struct work_struct *dummy)
+{
+ struct cn_msg *msg;
+ struct hv_kvp_msg *message;
+ struct hv_kvp_msg *in_msg;
+ __u8 operation = kvp_transaction.kvp_msg->kvp_hdr.operation;
+ __u8 pool = kvp_transaction.kvp_msg->kvp_hdr.pool;
+ __u32 val32;
+ __u64 val64;
+ int rc;
+
+ msg = kzalloc(sizeof(*msg) + sizeof(struct hv_kvp_msg) , GFP_ATOMIC);
+ if (!msg)
+ return;
+
+ msg->id.idx = CN_KVP_IDX;
+ msg->id.val = CN_KVP_VAL;
+
+ message = (struct hv_kvp_msg *)msg->data;
+ message->kvp_hdr.operation = operation;
+ message->kvp_hdr.pool = pool;
+ in_msg = kvp_transaction.kvp_msg;
+
+ /*
+ * The key/value strings sent from the host are encoded in
+ * in utf16; convert it to utf8 strings.
+ * The host assures us that the utf16 strings will not exceed
+ * the max lengths specified. We will however, reserve room
+ * for the string terminating character - in the utf16s_utf8s()
+ * function we limit the size of the buffer where the converted
+ * string is placed to HV_KVP_EXCHANGE_MAX_*_SIZE -1 to gaurantee
+ * that the strings can be properly terminated!
+ */
+
+ switch (message->kvp_hdr.operation) {
+ case KVP_OP_SET_IP_INFO:
+ process_ib_ipinfo(in_msg, message, KVP_OP_SET_IP_INFO);
+ break;
+ case KVP_OP_GET_IP_INFO:
+ process_ib_ipinfo(in_msg, message, KVP_OP_GET_IP_INFO);
+ break;
+ case KVP_OP_SET:
+ switch (in_msg->body.kvp_set.data.value_type) {
+ case REG_SZ:
+ /*
+ * The value is a string - utf16 encoding.
+ */
+ message->body.kvp_set.data.value_size =
+ utf16s_to_utf8s(
+ (wchar_t *)in_msg->body.kvp_set.data.value,
+ in_msg->body.kvp_set.data.value_size,
+ UTF16_LITTLE_ENDIAN,
+ message->body.kvp_set.data.value,
+ HV_KVP_EXCHANGE_MAX_VALUE_SIZE - 1) + 1;
+ break;
+
+ case REG_U32:
+ /*
+ * The value is a 32 bit scalar.
+ * We save this as a utf8 string.
+ */
+ val32 = in_msg->body.kvp_set.data.value_u32;
+ message->body.kvp_set.data.value_size =
+ sprintf(message->body.kvp_set.data.value,
+ "%d", val32) + 1;
+ break;
+
+ case REG_U64:
+ /*
+ * The value is a 64 bit scalar.
+ * We save this as a utf8 string.
+ */
+ val64 = in_msg->body.kvp_set.data.value_u64;
+ message->body.kvp_set.data.value_size =
+ sprintf(message->body.kvp_set.data.value,
+ "%llu", val64) + 1;
+ break;
+
+ }
+ case KVP_OP_GET:
+ message->body.kvp_set.data.key_size =
+ utf16s_to_utf8s(
+ (wchar_t *)in_msg->body.kvp_set.data.key,
+ in_msg->body.kvp_set.data.key_size,
+ UTF16_LITTLE_ENDIAN,
+ message->body.kvp_set.data.key,
+ HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1) + 1;
+ break;
+
+ case KVP_OP_DELETE:
+ message->body.kvp_delete.key_size =
+ utf16s_to_utf8s(
+ (wchar_t *)in_msg->body.kvp_delete.key,
+ in_msg->body.kvp_delete.key_size,
+ UTF16_LITTLE_ENDIAN,
+ message->body.kvp_delete.key,
+ HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1) + 1;
+ break;
+
+ case KVP_OP_ENUMERATE:
+ message->body.kvp_enum_data.index =
+ in_msg->body.kvp_enum_data.index;
+ break;
+ }
+
+ msg->len = sizeof(struct hv_kvp_msg);
+ rc = cn_netlink_send(msg, 0, 0, GFP_ATOMIC);
+ if (rc) {
+ pr_debug("KVP: failed to communicate to the daemon: %d\n", rc);
+ if (cancel_delayed_work_sync(&kvp_work))
+ kvp_respond_to_host(message, HV_E_FAIL);
+ }
+
+ kfree(msg);
+
+ return;
+}
+
+/*
+ * Send a response back to the host.
+ */
+
+static void
+kvp_respond_to_host(struct hv_kvp_msg *msg_to_host, int error)
+{
+ struct hv_kvp_msg *kvp_msg;
+ struct hv_kvp_exchg_msg_value *kvp_data;
+ char *key_name;
+ char *value;
+ struct icmsg_hdr *icmsghdrp;
+ int keylen = 0;
+ int valuelen = 0;
+ u32 buf_len;
+ struct vmbus_channel *channel;
+ u64 req_id;
+ int ret;
+
+ /*
+ * If a transaction is not active; log and return.
+ */
+
+ if (!kvp_transaction.active) {
+ /*
+ * This is a spurious call!
+ */
+ pr_warn("KVP: Transaction not active\n");
+ return;
+ }
+ /*
+ * Copy the global state for completing the transaction. Note that
+ * only one transaction can be active at a time.
+ */
+
+ buf_len = kvp_transaction.recv_len;
+ channel = kvp_transaction.recv_channel;
+ req_id = kvp_transaction.recv_req_id;
+
+ kvp_transaction.active = false;
+
+ icmsghdrp = (struct icmsg_hdr *)
+ &recv_buffer[sizeof(struct vmbuspipe_hdr)];
+
+ if (channel->onchannel_callback == NULL)
+ /*
+ * We have raced with util driver being unloaded;
+ * silently return.
+ */
+ return;
+
+ icmsghdrp->status = error;
+
+ /*
+ * If the error parameter is set, terminate the host's enumeration
+ * on this pool.
+ */
+ if (error) {
+ /*
+ * Something failed or we have timedout;
+ * terminate the current host-side iteration.
+ */
+ goto response_done;
+ }
+
+ kvp_msg = (struct hv_kvp_msg *)
+ &recv_buffer[sizeof(struct vmbuspipe_hdr) +
+ sizeof(struct icmsg_hdr)];
+
+ switch (kvp_transaction.kvp_msg->kvp_hdr.operation) {
+ case KVP_OP_GET_IP_INFO:
+ ret = process_ob_ipinfo(msg_to_host,
+ (struct hv_kvp_ip_msg *)kvp_msg,
+ KVP_OP_GET_IP_INFO);
+ if (ret < 0)
+ icmsghdrp->status = HV_E_FAIL;
+
+ goto response_done;
+ case KVP_OP_SET_IP_INFO:
+ goto response_done;
+ case KVP_OP_GET:
+ kvp_data = &kvp_msg->body.kvp_get.data;
+ goto copy_value;
+
+ case KVP_OP_SET:
+ case KVP_OP_DELETE:
+ goto response_done;
+
+ default:
+ break;
+ }
+
+ kvp_data = &kvp_msg->body.kvp_enum_data.data;
+ key_name = msg_to_host->body.kvp_enum_data.data.key;
+
+ /*
+ * The windows host expects the key/value pair to be encoded
+ * in utf16. Ensure that the key/value size reported to the host
+ * will be less than or equal to the MAX size (including the
+ * terminating character).
+ */
+ keylen = utf8s_to_utf16s(key_name, strlen(key_name), UTF16_HOST_ENDIAN,
+ (wchar_t *) kvp_data->key,
+ (HV_KVP_EXCHANGE_MAX_KEY_SIZE / 2) - 2);
+ kvp_data->key_size = 2*(keylen + 1); /* utf16 encoding */
+
+copy_value:
+ value = msg_to_host->body.kvp_enum_data.data.value;
+ valuelen = utf8s_to_utf16s(value, strlen(value), UTF16_HOST_ENDIAN,
+ (wchar_t *) kvp_data->value,
+ (HV_KVP_EXCHANGE_MAX_VALUE_SIZE / 2) - 2);
+ kvp_data->value_size = 2*(valuelen + 1); /* utf16 encoding */
+
+ /*
+ * If the utf8s to utf16s conversion failed; notify host
+ * of the error.
+ */
+ if ((keylen < 0) || (valuelen < 0))
+ icmsghdrp->status = HV_E_FAIL;
+
+ kvp_data->value_type = REG_SZ; /* all our values are strings */
+
+response_done:
+ icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;
+
+ vmbus_sendpacket(channel, recv_buffer, buf_len, req_id,
+ VM_PKT_DATA_INBAND, 0);
+ poll_channel(channel);
+}
+
+/*
+ * This callback is invoked when we get a KVP message from the host.
+ * The host ensures that only one KVP transaction can be active at a time.
+ * KVP implementation in Linux needs to forward the key to a user-mde
+ * component to retrive the corresponding value. Consequently, we cannot
+ * respond to the host in the conext of this callback. Since the host
+ * guarantees that at most only one transaction can be active at a time,
+ * we stash away the transaction state in a set of global variables.
+ */
+
+void hv_kvp_onchannelcallback(void *context)
+{
+ struct vmbus_channel *channel = context;
+ u32 recvlen;
+ u64 requestid;
+
+ struct hv_kvp_msg *kvp_msg;
+
+ struct icmsg_hdr *icmsghdrp;
+ struct icmsg_negotiate *negop = NULL;
+ int util_fw_version;
+ int kvp_srv_version;
+
+ if (kvp_transaction.active) {
+ /*
+ * We will defer processing this callback once
+ * the current transaction is complete.
+ */
+ kvp_transaction.kvp_context = context;
+ return;
+ }
+
+ vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 4, &recvlen,
+ &requestid);
+
+ if (recvlen > 0) {
+ icmsghdrp = (struct icmsg_hdr *)&recv_buffer[
+ sizeof(struct vmbuspipe_hdr)];
+
+ if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
+ /*
+ * Based on the host, select appropriate
+ * framework and service versions we will
+ * negotiate.
+ */
+ switch (vmbus_proto_version) {
+ case (VERSION_WS2008):
+ util_fw_version = UTIL_WS2K8_FW_VERSION;
+ kvp_srv_version = WS2008_SRV_VERSION;
+ break;
+ case (VERSION_WIN7):
+ util_fw_version = UTIL_FW_VERSION;
+ kvp_srv_version = WIN7_SRV_VERSION;
+ break;
+ default:
+ util_fw_version = UTIL_FW_VERSION;
+ kvp_srv_version = WIN8_SRV_VERSION;
+ }
+ vmbus_prep_negotiate_resp(icmsghdrp, negop,
+ recv_buffer, util_fw_version,
+ kvp_srv_version);
+
+ } else {
+ kvp_msg = (struct hv_kvp_msg *)&recv_buffer[
+ sizeof(struct vmbuspipe_hdr) +
+ sizeof(struct icmsg_hdr)];
+
+ /*
+ * Stash away this global state for completing the
+ * transaction; note transactions are serialized.
+ */
+
+ kvp_transaction.recv_len = recvlen;
+ kvp_transaction.recv_channel = channel;
+ kvp_transaction.recv_req_id = requestid;
+ kvp_transaction.active = true;
+ kvp_transaction.kvp_msg = kvp_msg;
+
+ /*
+ * Get the information from the
+ * user-mode component.
+ * component. This transaction will be
+ * completed when we get the value from
+ * the user-mode component.
+ * Set a timeout to deal with
+ * user-mode not responding.
+ */
+ schedule_work(&kvp_sendkey_work);
+ schedule_delayed_work(&kvp_work, 5*HZ);
+
+ return;
+
+ }
+
+ icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
+ | ICMSGHDRFLAG_RESPONSE;
+
+ vmbus_sendpacket(channel, recv_buffer,
+ recvlen, requestid,
+ VM_PKT_DATA_INBAND, 0);
+ }
+
+}
+
+int
+hv_kvp_init(struct hv_util_service *srv)
+{
+ int err;
+
+ err = cn_add_callback(&kvp_id, kvp_name, kvp_cn_callback);
+ if (err)
+ return err;
+ recv_buffer = srv->recv_buffer;
+
+ /*
+ * When this driver loads, the user level daemon that
+ * processes the host requests may not yet be running.
+ * Defer processing channel callbacks until the daemon
+ * has registered.
+ */
+ kvp_transaction.active = true;
+
+ return 0;
+}
+
+void hv_kvp_deinit(void)
+{
+ cn_del_callback(&kvp_id);
+ cancel_delayed_work_sync(&kvp_work);
+ cancel_work_sync(&kvp_sendkey_work);
+}
diff --git a/drivers/hv/hv_snapshot.c b/drivers/hv/hv_snapshot.c
new file mode 100644
index 000000000..9d5e0d1ef
--- /dev/null
+++ b/drivers/hv/hv_snapshot.c
@@ -0,0 +1,303 @@
+/*
+ * An implementation of host initiated guest snapshot.
+ *
+ *
+ * Copyright (C) 2013, Microsoft, Inc.
+ * Author : K. Y. Srinivasan <kys@microsoft.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for more
+ * details.
+ *
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/net.h>
+#include <linux/nls.h>
+#include <linux/connector.h>
+#include <linux/workqueue.h>
+#include <linux/hyperv.h>
+
+#define VSS_MAJOR 5
+#define VSS_MINOR 0
+#define VSS_VERSION (VSS_MAJOR << 16 | VSS_MINOR)
+
+#define VSS_USERSPACE_TIMEOUT (msecs_to_jiffies(10 * 1000))
+
+/*
+ * Global state maintained for transaction that is being processed.
+ * Note that only one transaction can be active at any point in time.
+ *
+ * This state is set when we receive a request from the host; we
+ * cleanup this state when the transaction is completed - when we respond
+ * to the host with the key value.
+ */
+
+static struct {
+ bool active; /* transaction status - active or not */
+ int recv_len; /* number of bytes received. */
+ struct vmbus_channel *recv_channel; /* chn we got the request */
+ u64 recv_req_id; /* request ID. */
+ struct hv_vss_msg *msg; /* current message */
+} vss_transaction;
+
+
+static void vss_respond_to_host(int error);
+
+static struct cb_id vss_id = { CN_VSS_IDX, CN_VSS_VAL };
+static const char vss_name[] = "vss_kernel_module";
+static __u8 *recv_buffer;
+
+static void vss_send_op(struct work_struct *dummy);
+static void vss_timeout_func(struct work_struct *dummy);
+
+static DECLARE_DELAYED_WORK(vss_timeout_work, vss_timeout_func);
+static DECLARE_WORK(vss_send_op_work, vss_send_op);
+
+/*
+ * Callback when data is received from user mode.
+ */
+
+static void vss_timeout_func(struct work_struct *dummy)
+{
+ /*
+ * Timeout waiting for userspace component to reply happened.
+ */
+ pr_warn("VSS: timeout waiting for daemon to reply\n");
+ vss_respond_to_host(HV_E_FAIL);
+}
+
+static void
+vss_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
+{
+ struct hv_vss_msg *vss_msg;
+
+ vss_msg = (struct hv_vss_msg *)msg->data;
+
+ if (vss_msg->vss_hdr.operation == VSS_OP_REGISTER) {
+ pr_info("VSS daemon registered\n");
+ vss_transaction.active = false;
+ if (vss_transaction.recv_channel != NULL)
+ hv_vss_onchannelcallback(vss_transaction.recv_channel);
+ return;
+
+ }
+ if (cancel_delayed_work_sync(&vss_timeout_work))
+ vss_respond_to_host(vss_msg->error);
+}
+
+
+static void vss_send_op(struct work_struct *dummy)
+{
+ int op = vss_transaction.msg->vss_hdr.operation;
+ int rc;
+ struct cn_msg *msg;
+ struct hv_vss_msg *vss_msg;
+
+ msg = kzalloc(sizeof(*msg) + sizeof(*vss_msg), GFP_ATOMIC);
+ if (!msg)
+ return;
+
+ vss_msg = (struct hv_vss_msg *)msg->data;
+
+ msg->id.idx = CN_VSS_IDX;
+ msg->id.val = CN_VSS_VAL;
+
+ vss_msg->vss_hdr.operation = op;
+ msg->len = sizeof(struct hv_vss_msg);
+
+ rc = cn_netlink_send(msg, 0, 0, GFP_ATOMIC);
+ if (rc) {
+ pr_warn("VSS: failed to communicate to the daemon: %d\n", rc);
+ if (cancel_delayed_work_sync(&vss_timeout_work))
+ vss_respond_to_host(HV_E_FAIL);
+ }
+ kfree(msg);
+
+ return;
+}
+
+/*
+ * Send a response back to the host.
+ */
+
+static void
+vss_respond_to_host(int error)
+{
+ struct icmsg_hdr *icmsghdrp;
+ u32 buf_len;
+ struct vmbus_channel *channel;
+ u64 req_id;
+
+ /*
+ * If a transaction is not active; log and return.
+ */
+
+ if (!vss_transaction.active) {
+ /*
+ * This is a spurious call!
+ */
+ pr_warn("VSS: Transaction not active\n");
+ return;
+ }
+ /*
+ * Copy the global state for completing the transaction. Note that
+ * only one transaction can be active at a time.
+ */
+
+ buf_len = vss_transaction.recv_len;
+ channel = vss_transaction.recv_channel;
+ req_id = vss_transaction.recv_req_id;
+ vss_transaction.active = false;
+
+ icmsghdrp = (struct icmsg_hdr *)
+ &recv_buffer[sizeof(struct vmbuspipe_hdr)];
+
+ if (channel->onchannel_callback == NULL)
+ /*
+ * We have raced with util driver being unloaded;
+ * silently return.
+ */
+ return;
+
+ icmsghdrp->status = error;
+
+ icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;
+
+ vmbus_sendpacket(channel, recv_buffer, buf_len, req_id,
+ VM_PKT_DATA_INBAND, 0);
+
+}
+
+/*
+ * This callback is invoked when we get a VSS message from the host.
+ * The host ensures that only one VSS transaction can be active at a time.
+ */
+
+void hv_vss_onchannelcallback(void *context)
+{
+ struct vmbus_channel *channel = context;
+ u32 recvlen;
+ u64 requestid;
+ struct hv_vss_msg *vss_msg;
+
+
+ struct icmsg_hdr *icmsghdrp;
+ struct icmsg_negotiate *negop = NULL;
+
+ if (vss_transaction.active) {
+ /*
+ * We will defer processing this callback once
+ * the current transaction is complete.
+ */
+ vss_transaction.recv_channel = channel;
+ return;
+ }
+
+ vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 2, &recvlen,
+ &requestid);
+
+ if (recvlen > 0) {
+ icmsghdrp = (struct icmsg_hdr *)&recv_buffer[
+ sizeof(struct vmbuspipe_hdr)];
+
+ if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
+ vmbus_prep_negotiate_resp(icmsghdrp, negop,
+ recv_buffer, UTIL_FW_VERSION,
+ VSS_VERSION);
+ } else {
+ vss_msg = (struct hv_vss_msg *)&recv_buffer[
+ sizeof(struct vmbuspipe_hdr) +
+ sizeof(struct icmsg_hdr)];
+
+ /*
+ * Stash away this global state for completing the
+ * transaction; note transactions are serialized.
+ */
+
+ vss_transaction.recv_len = recvlen;
+ vss_transaction.recv_channel = channel;
+ vss_transaction.recv_req_id = requestid;
+ vss_transaction.active = true;
+ vss_transaction.msg = (struct hv_vss_msg *)vss_msg;
+
+ switch (vss_msg->vss_hdr.operation) {
+ /*
+ * Initiate a "freeze/thaw"
+ * operation in the guest.
+ * We respond to the host once
+ * the operation is complete.
+ *
+ * We send the message to the
+ * user space daemon and the
+ * operation is performed in
+ * the daemon.
+ */
+ case VSS_OP_FREEZE:
+ case VSS_OP_THAW:
+ schedule_work(&vss_send_op_work);
+ schedule_delayed_work(&vss_timeout_work,
+ VSS_USERSPACE_TIMEOUT);
+ return;
+
+ case VSS_OP_HOT_BACKUP:
+ vss_msg->vss_cf.flags =
+ VSS_HBU_NO_AUTO_RECOVERY;
+ vss_respond_to_host(0);
+ return;
+
+ case VSS_OP_GET_DM_INFO:
+ vss_msg->dm_info.flags = 0;
+ vss_respond_to_host(0);
+ return;
+
+ default:
+ vss_respond_to_host(0);
+ return;
+
+ }
+
+ }
+
+ icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
+ | ICMSGHDRFLAG_RESPONSE;
+
+ vmbus_sendpacket(channel, recv_buffer,
+ recvlen, requestid,
+ VM_PKT_DATA_INBAND, 0);
+ }
+
+}
+
+int
+hv_vss_init(struct hv_util_service *srv)
+{
+ int err;
+
+ err = cn_add_callback(&vss_id, vss_name, vss_cn_callback);
+ if (err)
+ return err;
+ recv_buffer = srv->recv_buffer;
+
+ /*
+ * When this driver loads, the user level daemon that
+ * processes the host requests may not yet be running.
+ * Defer processing channel callbacks until the daemon
+ * has registered.
+ */
+ vss_transaction.active = true;
+ return 0;
+}
+
+void hv_vss_deinit(void)
+{
+ cn_del_callback(&vss_id);
+ cancel_delayed_work_sync(&vss_timeout_work);
+ cancel_work_sync(&vss_send_op_work);
+}
diff --git a/drivers/hv/hv_util.c b/drivers/hv/hv_util.c
new file mode 100644
index 000000000..7994ec2e4
--- /dev/null
+++ b/drivers/hv/hv_util.c
@@ -0,0 +1,447 @@
+/*
+ * Copyright (c) 2010, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ * Haiyang Zhang <haiyangz@microsoft.com>
+ * Hank Janssen <hjanssen@microsoft.com>
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/sysctl.h>
+#include <linux/reboot.h>
+#include <linux/hyperv.h>
+
+#include "hyperv_vmbus.h"
+
+#define SD_MAJOR 3
+#define SD_MINOR 0
+#define SD_VERSION (SD_MAJOR << 16 | SD_MINOR)
+
+#define SD_WS2008_MAJOR 1
+#define SD_WS2008_VERSION (SD_WS2008_MAJOR << 16 | SD_MINOR)
+
+#define TS_MAJOR 3
+#define TS_MINOR 0
+#define TS_VERSION (TS_MAJOR << 16 | TS_MINOR)
+
+#define TS_WS2008_MAJOR 1
+#define TS_WS2008_VERSION (TS_WS2008_MAJOR << 16 | TS_MINOR)
+
+#define HB_MAJOR 3
+#define HB_MINOR 0
+#define HB_VERSION (HB_MAJOR << 16 | HB_MINOR)
+
+#define HB_WS2008_MAJOR 1
+#define HB_WS2008_VERSION (HB_WS2008_MAJOR << 16 | HB_MINOR)
+
+static int sd_srv_version;
+static int ts_srv_version;
+static int hb_srv_version;
+static int util_fw_version;
+
+static void shutdown_onchannelcallback(void *context);
+static struct hv_util_service util_shutdown = {
+ .util_cb = shutdown_onchannelcallback,
+};
+
+static void timesync_onchannelcallback(void *context);
+static struct hv_util_service util_timesynch = {
+ .util_cb = timesync_onchannelcallback,
+};
+
+static void heartbeat_onchannelcallback(void *context);
+static struct hv_util_service util_heartbeat = {
+ .util_cb = heartbeat_onchannelcallback,
+};
+
+static struct hv_util_service util_kvp = {
+ .util_cb = hv_kvp_onchannelcallback,
+ .util_init = hv_kvp_init,
+ .util_deinit = hv_kvp_deinit,
+};
+
+static struct hv_util_service util_vss = {
+ .util_cb = hv_vss_onchannelcallback,
+ .util_init = hv_vss_init,
+ .util_deinit = hv_vss_deinit,
+};
+
+static struct hv_util_service util_fcopy = {
+ .util_cb = hv_fcopy_onchannelcallback,
+ .util_init = hv_fcopy_init,
+ .util_deinit = hv_fcopy_deinit,
+};
+
+static void perform_shutdown(struct work_struct *dummy)
+{
+ orderly_poweroff(true);
+}
+
+/*
+ * Perform the shutdown operation in a thread context.
+ */
+static DECLARE_WORK(shutdown_work, perform_shutdown);
+
+static void shutdown_onchannelcallback(void *context)
+{
+ struct vmbus_channel *channel = context;
+ u32 recvlen;
+ u64 requestid;
+ bool execute_shutdown = false;
+ u8 *shut_txf_buf = util_shutdown.recv_buffer;
+
+ struct shutdown_msg_data *shutdown_msg;
+
+ struct icmsg_hdr *icmsghdrp;
+ struct icmsg_negotiate *negop = NULL;
+
+ vmbus_recvpacket(channel, shut_txf_buf,
+ PAGE_SIZE, &recvlen, &requestid);
+
+ if (recvlen > 0) {
+ icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[
+ sizeof(struct vmbuspipe_hdr)];
+
+ if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
+ vmbus_prep_negotiate_resp(icmsghdrp, negop,
+ shut_txf_buf, util_fw_version,
+ sd_srv_version);
+ } else {
+ shutdown_msg =
+ (struct shutdown_msg_data *)&shut_txf_buf[
+ sizeof(struct vmbuspipe_hdr) +
+ sizeof(struct icmsg_hdr)];
+
+ switch (shutdown_msg->flags) {
+ case 0:
+ case 1:
+ icmsghdrp->status = HV_S_OK;
+ execute_shutdown = true;
+
+ pr_info("Shutdown request received -"
+ " graceful shutdown initiated\n");
+ break;
+ default:
+ icmsghdrp->status = HV_E_FAIL;
+ execute_shutdown = false;
+
+ pr_info("Shutdown request received -"
+ " Invalid request\n");
+ break;
+ }
+ }
+
+ icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
+ | ICMSGHDRFLAG_RESPONSE;
+
+ vmbus_sendpacket(channel, shut_txf_buf,
+ recvlen, requestid,
+ VM_PKT_DATA_INBAND, 0);
+ }
+
+ if (execute_shutdown == true)
+ schedule_work(&shutdown_work);
+}
+
+/*
+ * Set guest time to host UTC time.
+ */
+static inline void do_adj_guesttime(u64 hosttime)
+{
+ s64 host_tns;
+ struct timespec host_ts;
+
+ host_tns = (hosttime - WLTIMEDELTA) * 100;
+ host_ts = ns_to_timespec(host_tns);
+
+ do_settimeofday(&host_ts);
+}
+
+/*
+ * Set the host time in a process context.
+ */
+
+struct adj_time_work {
+ struct work_struct work;
+ u64 host_time;
+};
+
+static void hv_set_host_time(struct work_struct *work)
+{
+ struct adj_time_work *wrk;
+
+ wrk = container_of(work, struct adj_time_work, work);
+ do_adj_guesttime(wrk->host_time);
+ kfree(wrk);
+}
+
+/*
+ * Synchronize time with host after reboot, restore, etc.
+ *
+ * ICTIMESYNCFLAG_SYNC flag bit indicates reboot, restore events of the VM.
+ * After reboot the flag ICTIMESYNCFLAG_SYNC is included in the first time
+ * message after the timesync channel is opened. Since the hv_utils module is
+ * loaded after hv_vmbus, the first message is usually missed. The other
+ * thing is, systime is automatically set to emulated hardware clock which may
+ * not be UTC time or in the same time zone. So, to override these effects, we
+ * use the first 50 time samples for initial system time setting.
+ */
+static inline void adj_guesttime(u64 hosttime, u8 flags)
+{
+ struct adj_time_work *wrk;
+ static s32 scnt = 50;
+
+ wrk = kmalloc(sizeof(struct adj_time_work), GFP_ATOMIC);
+ if (wrk == NULL)
+ return;
+
+ wrk->host_time = hosttime;
+ if ((flags & ICTIMESYNCFLAG_SYNC) != 0) {
+ INIT_WORK(&wrk->work, hv_set_host_time);
+ schedule_work(&wrk->work);
+ return;
+ }
+
+ if ((flags & ICTIMESYNCFLAG_SAMPLE) != 0 && scnt > 0) {
+ scnt--;
+ INIT_WORK(&wrk->work, hv_set_host_time);
+ schedule_work(&wrk->work);
+ } else
+ kfree(wrk);
+}
+
+/*
+ * Time Sync Channel message handler.
+ */
+static void timesync_onchannelcallback(void *context)
+{
+ struct vmbus_channel *channel = context;
+ u32 recvlen;
+ u64 requestid;
+ struct icmsg_hdr *icmsghdrp;
+ struct ictimesync_data *timedatap;
+ u8 *time_txf_buf = util_timesynch.recv_buffer;
+ struct icmsg_negotiate *negop = NULL;
+
+ vmbus_recvpacket(channel, time_txf_buf,
+ PAGE_SIZE, &recvlen, &requestid);
+
+ if (recvlen > 0) {
+ icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
+ sizeof(struct vmbuspipe_hdr)];
+
+ if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
+ vmbus_prep_negotiate_resp(icmsghdrp, negop,
+ time_txf_buf,
+ util_fw_version,
+ ts_srv_version);
+ } else {
+ timedatap = (struct ictimesync_data *)&time_txf_buf[
+ sizeof(struct vmbuspipe_hdr) +
+ sizeof(struct icmsg_hdr)];
+ adj_guesttime(timedatap->parenttime, timedatap->flags);
+ }
+
+ icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
+ | ICMSGHDRFLAG_RESPONSE;
+
+ vmbus_sendpacket(channel, time_txf_buf,
+ recvlen, requestid,
+ VM_PKT_DATA_INBAND, 0);
+ }
+}
+
+/*
+ * Heartbeat functionality.
+ * Every two seconds, Hyper-V send us a heartbeat request message.
+ * we respond to this message, and Hyper-V knows we are alive.
+ */
+static void heartbeat_onchannelcallback(void *context)
+{
+ struct vmbus_channel *channel = context;
+ u32 recvlen;
+ u64 requestid;
+ struct icmsg_hdr *icmsghdrp;
+ struct heartbeat_msg_data *heartbeat_msg;
+ u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
+ struct icmsg_negotiate *negop = NULL;
+
+ vmbus_recvpacket(channel, hbeat_txf_buf,
+ PAGE_SIZE, &recvlen, &requestid);
+
+ if (recvlen > 0) {
+ icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
+ sizeof(struct vmbuspipe_hdr)];
+
+ if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
+ vmbus_prep_negotiate_resp(icmsghdrp, negop,
+ hbeat_txf_buf, util_fw_version,
+ hb_srv_version);
+ } else {
+ heartbeat_msg =
+ (struct heartbeat_msg_data *)&hbeat_txf_buf[
+ sizeof(struct vmbuspipe_hdr) +
+ sizeof(struct icmsg_hdr)];
+
+ heartbeat_msg->seq_num += 1;
+ }
+
+ icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
+ | ICMSGHDRFLAG_RESPONSE;
+
+ vmbus_sendpacket(channel, hbeat_txf_buf,
+ recvlen, requestid,
+ VM_PKT_DATA_INBAND, 0);
+ }
+}
+
+static int util_probe(struct hv_device *dev,
+ const struct hv_vmbus_device_id *dev_id)
+{
+ struct hv_util_service *srv =
+ (struct hv_util_service *)dev_id->driver_data;
+ int ret;
+
+ srv->recv_buffer = kmalloc(PAGE_SIZE * 4, GFP_KERNEL);
+ if (!srv->recv_buffer)
+ return -ENOMEM;
+ if (srv->util_init) {
+ ret = srv->util_init(srv);
+ if (ret) {
+ ret = -ENODEV;
+ goto error1;
+ }
+ }
+
+ /*
+ * The set of services managed by the util driver are not performance
+ * critical and do not need batched reading. Furthermore, some services
+ * such as KVP can only handle one message from the host at a time.
+ * Turn off batched reading for all util drivers before we open the
+ * channel.
+ */
+
+ set_channel_read_state(dev->channel, false);
+
+ hv_set_drvdata(dev, srv);
+
+ /*
+ * Based on the host; initialize the framework and
+ * service version numbers we will negotiate.
+ */
+ switch (vmbus_proto_version) {
+ case (VERSION_WS2008):
+ util_fw_version = UTIL_WS2K8_FW_VERSION;
+ sd_srv_version = SD_WS2008_VERSION;
+ ts_srv_version = TS_WS2008_VERSION;
+ hb_srv_version = HB_WS2008_VERSION;
+ break;
+
+ default:
+ util_fw_version = UTIL_FW_VERSION;
+ sd_srv_version = SD_VERSION;
+ ts_srv_version = TS_VERSION;
+ hb_srv_version = HB_VERSION;
+ }
+
+ ret = vmbus_open(dev->channel, 4 * PAGE_SIZE, 4 * PAGE_SIZE, NULL, 0,
+ srv->util_cb, dev->channel);
+ if (ret)
+ goto error;
+
+ return 0;
+
+error:
+ if (srv->util_deinit)
+ srv->util_deinit();
+error1:
+ kfree(srv->recv_buffer);
+ return ret;
+}
+
+static int util_remove(struct hv_device *dev)
+{
+ struct hv_util_service *srv = hv_get_drvdata(dev);
+
+ if (srv->util_deinit)
+ srv->util_deinit();
+ vmbus_close(dev->channel);
+ kfree(srv->recv_buffer);
+
+ return 0;
+}
+
+static const struct hv_vmbus_device_id id_table[] = {
+ /* Shutdown guid */
+ { HV_SHUTDOWN_GUID,
+ .driver_data = (unsigned long)&util_shutdown
+ },
+ /* Time synch guid */
+ { HV_TS_GUID,
+ .driver_data = (unsigned long)&util_timesynch
+ },
+ /* Heartbeat guid */
+ { HV_HEART_BEAT_GUID,
+ .driver_data = (unsigned long)&util_heartbeat
+ },
+ /* KVP guid */
+ { HV_KVP_GUID,
+ .driver_data = (unsigned long)&util_kvp
+ },
+ /* VSS GUID */
+ { HV_VSS_GUID,
+ .driver_data = (unsigned long)&util_vss
+ },
+ /* File copy GUID */
+ { HV_FCOPY_GUID,
+ .driver_data = (unsigned long)&util_fcopy
+ },
+ { },
+};
+
+MODULE_DEVICE_TABLE(vmbus, id_table);
+
+/* The one and only one */
+static struct hv_driver util_drv = {
+ .name = "hv_util",
+ .id_table = id_table,
+ .probe = util_probe,
+ .remove = util_remove,
+};
+
+static int __init init_hyperv_utils(void)
+{
+ pr_info("Registering HyperV Utility Driver\n");
+
+ return vmbus_driver_register(&util_drv);
+}
+
+static void exit_hyperv_utils(void)
+{
+ pr_info("De-Registered HyperV Utility Driver\n");
+
+ vmbus_driver_unregister(&util_drv);
+}
+
+module_init(init_hyperv_utils);
+module_exit(exit_hyperv_utils);
+
+MODULE_DESCRIPTION("Hyper-V Utilities");
+MODULE_LICENSE("GPL");
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
new file mode 100644
index 000000000..887287ad4
--- /dev/null
+++ b/drivers/hv/hyperv_vmbus.h
@@ -0,0 +1,738 @@
+/*
+ *
+ * Copyright (c) 2011, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ * Haiyang Zhang <haiyangz@microsoft.com>
+ * Hank Janssen <hjanssen@microsoft.com>
+ * K. Y. Srinivasan <kys@microsoft.com>
+ *
+ */
+
+#ifndef _HYPERV_VMBUS_H
+#define _HYPERV_VMBUS_H
+
+#include <linux/list.h>
+#include <asm/sync_bitops.h>
+#include <linux/atomic.h>
+#include <linux/hyperv.h>
+
+/*
+ * The below CPUID leaves are present if VersionAndFeatures.HypervisorPresent
+ * is set by CPUID(HVCPUID_VERSION_FEATURES).
+ */
+enum hv_cpuid_function {
+ HVCPUID_VERSION_FEATURES = 0x00000001,
+ HVCPUID_VENDOR_MAXFUNCTION = 0x40000000,
+ HVCPUID_INTERFACE = 0x40000001,
+
+ /*
+ * The remaining functions depend on the value of
+ * HVCPUID_INTERFACE
+ */
+ HVCPUID_VERSION = 0x40000002,
+ HVCPUID_FEATURES = 0x40000003,
+ HVCPUID_ENLIGHTENMENT_INFO = 0x40000004,
+ HVCPUID_IMPLEMENTATION_LIMITS = 0x40000005,
+};
+
+#define HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE 0x400
+
+#define HV_X64_MSR_CRASH_P0 0x40000100
+#define HV_X64_MSR_CRASH_P1 0x40000101
+#define HV_X64_MSR_CRASH_P2 0x40000102
+#define HV_X64_MSR_CRASH_P3 0x40000103
+#define HV_X64_MSR_CRASH_P4 0x40000104
+#define HV_X64_MSR_CRASH_CTL 0x40000105
+
+#define HV_CRASH_CTL_CRASH_NOTIFY (1ULL << 63)
+
+/* Define version of the synthetic interrupt controller. */
+#define HV_SYNIC_VERSION (1)
+
+/* Define the expected SynIC version. */
+#define HV_SYNIC_VERSION_1 (0x1)
+
+/* Define synthetic interrupt controller message constants. */
+#define HV_MESSAGE_SIZE (256)
+#define HV_MESSAGE_PAYLOAD_BYTE_COUNT (240)
+#define HV_MESSAGE_PAYLOAD_QWORD_COUNT (30)
+#define HV_ANY_VP (0xFFFFFFFF)
+
+/* Define synthetic interrupt controller flag constants. */
+#define HV_EVENT_FLAGS_COUNT (256 * 8)
+#define HV_EVENT_FLAGS_BYTE_COUNT (256)
+#define HV_EVENT_FLAGS_DWORD_COUNT (256 / sizeof(u32))
+
+/* Define hypervisor message types. */
+enum hv_message_type {
+ HVMSG_NONE = 0x00000000,
+
+ /* Memory access messages. */
+ HVMSG_UNMAPPED_GPA = 0x80000000,
+ HVMSG_GPA_INTERCEPT = 0x80000001,
+
+ /* Timer notification messages. */
+ HVMSG_TIMER_EXPIRED = 0x80000010,
+
+ /* Error messages. */
+ HVMSG_INVALID_VP_REGISTER_VALUE = 0x80000020,
+ HVMSG_UNRECOVERABLE_EXCEPTION = 0x80000021,
+ HVMSG_UNSUPPORTED_FEATURE = 0x80000022,
+
+ /* Trace buffer complete messages. */
+ HVMSG_EVENTLOG_BUFFERCOMPLETE = 0x80000040,
+
+ /* Platform-specific processor intercept messages. */
+ HVMSG_X64_IOPORT_INTERCEPT = 0x80010000,
+ HVMSG_X64_MSR_INTERCEPT = 0x80010001,
+ HVMSG_X64_CPUID_INTERCEPT = 0x80010002,
+ HVMSG_X64_EXCEPTION_INTERCEPT = 0x80010003,
+ HVMSG_X64_APIC_EOI = 0x80010004,
+ HVMSG_X64_LEGACY_FP_ERROR = 0x80010005
+};
+
+/* Define the number of synthetic interrupt sources. */
+#define HV_SYNIC_SINT_COUNT (16)
+#define HV_SYNIC_STIMER_COUNT (4)
+
+/* Define invalid partition identifier. */
+#define HV_PARTITION_ID_INVALID ((u64)0x0)
+
+/* Define port identifier type. */
+union hv_port_id {
+ u32 asu32;
+ struct {
+ u32 id:24;
+ u32 reserved:8;
+ } u ;
+};
+
+/* Define port type. */
+enum hv_port_type {
+ HVPORT_MSG = 1,
+ HVPORT_EVENT = 2,
+ HVPORT_MONITOR = 3
+};
+
+/* Define port information structure. */
+struct hv_port_info {
+ enum hv_port_type port_type;
+ u32 padding;
+ union {
+ struct {
+ u32 target_sint;
+ u32 target_vp;
+ u64 rsvdz;
+ } message_port_info;
+ struct {
+ u32 target_sint;
+ u32 target_vp;
+ u16 base_flag_bumber;
+ u16 flag_count;
+ u32 rsvdz;
+ } event_port_info;
+ struct {
+ u64 monitor_address;
+ u64 rsvdz;
+ } monitor_port_info;
+ };
+};
+
+struct hv_connection_info {
+ enum hv_port_type port_type;
+ u32 padding;
+ union {
+ struct {
+ u64 rsvdz;
+ } message_connection_info;
+ struct {
+ u64 rsvdz;
+ } event_connection_info;
+ struct {
+ u64 monitor_address;
+ } monitor_connection_info;
+ };
+};
+
+/* Define synthetic interrupt controller message flags. */
+union hv_message_flags {
+ u8 asu8;
+ struct {
+ u8 msg_pending:1;
+ u8 reserved:7;
+ };
+};
+
+/* Define synthetic interrupt controller message header. */
+struct hv_message_header {
+ enum hv_message_type message_type;
+ u8 payload_size;
+ union hv_message_flags message_flags;
+ u8 reserved[2];
+ union {
+ u64 sender;
+ union hv_port_id port;
+ };
+};
+
+/*
+ * Timer configuration register.
+ */
+union hv_timer_config {
+ u64 as_uint64;
+ struct {
+ u64 enable:1;
+ u64 periodic:1;
+ u64 lazy:1;
+ u64 auto_enable:1;
+ u64 reserved_z0:12;
+ u64 sintx:4;
+ u64 reserved_z1:44;
+ };
+};
+
+
+/* Define timer message payload structure. */
+struct hv_timer_message_payload {
+ u32 timer_index;
+ u32 reserved;
+ u64 expiration_time; /* When the timer expired */
+ u64 delivery_time; /* When the message was delivered */
+};
+
+/* Define synthetic interrupt controller message format. */
+struct hv_message {
+ struct hv_message_header header;
+ union {
+ u64 payload[HV_MESSAGE_PAYLOAD_QWORD_COUNT];
+ } u ;
+};
+
+/* Define the number of message buffers associated with each port. */
+#define HV_PORT_MESSAGE_BUFFER_COUNT (16)
+
+/* Define the synthetic interrupt message page layout. */
+struct hv_message_page {
+ struct hv_message sint_message[HV_SYNIC_SINT_COUNT];
+};
+
+/* Define the synthetic interrupt controller event flags format. */
+union hv_synic_event_flags {
+ u8 flags8[HV_EVENT_FLAGS_BYTE_COUNT];
+ u32 flags32[HV_EVENT_FLAGS_DWORD_COUNT];
+};
+
+/* Define the synthetic interrupt flags page layout. */
+struct hv_synic_event_flags_page {
+ union hv_synic_event_flags sintevent_flags[HV_SYNIC_SINT_COUNT];
+};
+
+/* Define SynIC control register. */
+union hv_synic_scontrol {
+ u64 as_uint64;
+ struct {
+ u64 enable:1;
+ u64 reserved:63;
+ };
+};
+
+/* Define synthetic interrupt source. */
+union hv_synic_sint {
+ u64 as_uint64;
+ struct {
+ u64 vector:8;
+ u64 reserved1:8;
+ u64 masked:1;
+ u64 auto_eoi:1;
+ u64 reserved2:46;
+ };
+};
+
+/* Define the format of the SIMP register */
+union hv_synic_simp {
+ u64 as_uint64;
+ struct {
+ u64 simp_enabled:1;
+ u64 preserved:11;
+ u64 base_simp_gpa:52;
+ };
+};
+
+/* Define the format of the SIEFP register */
+union hv_synic_siefp {
+ u64 as_uint64;
+ struct {
+ u64 siefp_enabled:1;
+ u64 preserved:11;
+ u64 base_siefp_gpa:52;
+ };
+};
+
+/* Definitions for the monitored notification facility */
+union hv_monitor_trigger_group {
+ u64 as_uint64;
+ struct {
+ u32 pending;
+ u32 armed;
+ };
+};
+
+struct hv_monitor_parameter {
+ union hv_connection_id connectionid;
+ u16 flagnumber;
+ u16 rsvdz;
+};
+
+union hv_monitor_trigger_state {
+ u32 asu32;
+
+ struct {
+ u32 group_enable:4;
+ u32 rsvdz:28;
+ };
+};
+
+/* struct hv_monitor_page Layout */
+/* ------------------------------------------------------ */
+/* | 0 | TriggerState (4 bytes) | Rsvd1 (4 bytes) | */
+/* | 8 | TriggerGroup[0] | */
+/* | 10 | TriggerGroup[1] | */
+/* | 18 | TriggerGroup[2] | */
+/* | 20 | TriggerGroup[3] | */
+/* | 28 | Rsvd2[0] | */
+/* | 30 | Rsvd2[1] | */
+/* | 38 | Rsvd2[2] | */
+/* | 40 | NextCheckTime[0][0] | NextCheckTime[0][1] | */
+/* | ... | */
+/* | 240 | Latency[0][0..3] | */
+/* | 340 | Rsvz3[0] | */
+/* | 440 | Parameter[0][0] | */
+/* | 448 | Parameter[0][1] | */
+/* | ... | */
+/* | 840 | Rsvd4[0] | */
+/* ------------------------------------------------------ */
+struct hv_monitor_page {
+ union hv_monitor_trigger_state trigger_state;
+ u32 rsvdz1;
+
+ union hv_monitor_trigger_group trigger_group[4];
+ u64 rsvdz2[3];
+
+ s32 next_checktime[4][32];
+
+ u16 latency[4][32];
+ u64 rsvdz3[32];
+
+ struct hv_monitor_parameter parameter[4][32];
+
+ u8 rsvdz4[1984];
+};
+
+/* Declare the various hypercall operations. */
+enum hv_call_code {
+ HVCALL_POST_MESSAGE = 0x005c,
+ HVCALL_SIGNAL_EVENT = 0x005d,
+};
+
+/* Definition of the hv_post_message hypercall input structure. */
+struct hv_input_post_message {
+ union hv_connection_id connectionid;
+ u32 reserved;
+ enum hv_message_type message_type;
+ u32 payload_size;
+ u64 payload[HV_MESSAGE_PAYLOAD_QWORD_COUNT];
+};
+
+/*
+ * Versioning definitions used for guests reporting themselves to the
+ * hypervisor, and visa versa.
+ */
+
+/* Version info reported by guest OS's */
+enum hv_guest_os_vendor {
+ HVGUESTOS_VENDOR_MICROSOFT = 0x0001
+};
+
+enum hv_guest_os_microsoft_ids {
+ HVGUESTOS_MICROSOFT_UNDEFINED = 0x00,
+ HVGUESTOS_MICROSOFT_MSDOS = 0x01,
+ HVGUESTOS_MICROSOFT_WINDOWS3X = 0x02,
+ HVGUESTOS_MICROSOFT_WINDOWS9X = 0x03,
+ HVGUESTOS_MICROSOFT_WINDOWSNT = 0x04,
+ HVGUESTOS_MICROSOFT_WINDOWSCE = 0x05
+};
+
+/*
+ * Declare the MSR used to identify the guest OS.
+ */
+#define HV_X64_MSR_GUEST_OS_ID 0x40000000
+
+union hv_x64_msr_guest_os_id_contents {
+ u64 as_uint64;
+ struct {
+ u64 build_number:16;
+ u64 service_version:8; /* Service Pack, etc. */
+ u64 minor_version:8;
+ u64 major_version:8;
+ u64 os_id:8; /* enum hv_guest_os_microsoft_ids (if Vendor=MS) */
+ u64 vendor_id:16; /* enum hv_guest_os_vendor */
+ };
+};
+
+/*
+ * Declare the MSR used to setup pages used to communicate with the hypervisor.
+ */
+#define HV_X64_MSR_HYPERCALL 0x40000001
+
+union hv_x64_msr_hypercall_contents {
+ u64 as_uint64;
+ struct {
+ u64 enable:1;
+ u64 reserved:11;
+ u64 guest_physical_address:52;
+ };
+};
+
+
+enum {
+ VMBUS_MESSAGE_CONNECTION_ID = 1,
+ VMBUS_MESSAGE_PORT_ID = 1,
+ VMBUS_EVENT_CONNECTION_ID = 2,
+ VMBUS_EVENT_PORT_ID = 2,
+ VMBUS_MONITOR_CONNECTION_ID = 3,
+ VMBUS_MONITOR_PORT_ID = 3,
+ VMBUS_MESSAGE_SINT = 2,
+};
+
+/* #defines */
+
+#define HV_PRESENT_BIT 0x80000000
+
+/*
+ * The guest OS needs to register the guest ID with the hypervisor.
+ * The guest ID is a 64 bit entity and the structure of this ID is
+ * specified in the Hyper-V specification:
+ *
+ * http://msdn.microsoft.com/en-us/library/windows/hardware/ff542653%28v=vs.85%29.aspx
+ *
+ * While the current guideline does not specify how Linux guest ID(s)
+ * need to be generated, our plan is to publish the guidelines for
+ * Linux and other guest operating systems that currently are hosted
+ * on Hyper-V. The implementation here conforms to this yet
+ * unpublished guidelines.
+ *
+ *
+ * Bit(s)
+ * 63 - Indicates if the OS is Open Source or not; 1 is Open Source
+ * 62:56 - Os Type; Linux is 0x100
+ * 55:48 - Distro specific identification
+ * 47:16 - Linux kernel version number
+ * 15:0 - Distro specific identification
+ *
+ *
+ */
+
+#define HV_LINUX_VENDOR_ID 0x8100
+
+/*
+ * Generate the guest ID based on the guideline described above.
+ */
+
+static inline __u64 generate_guest_id(__u8 d_info1, __u32 kernel_version,
+ __u16 d_info2)
+{
+ __u64 guest_id = 0;
+
+ guest_id = (((__u64)HV_LINUX_VENDOR_ID) << 48);
+ guest_id |= (((__u64)(d_info1)) << 48);
+ guest_id |= (((__u64)(kernel_version)) << 16);
+ guest_id |= ((__u64)(d_info2));
+
+ return guest_id;
+}
+
+
+#define HV_CPU_POWER_MANAGEMENT (1 << 0)
+#define HV_RECOMMENDATIONS_MAX 4
+
+#define HV_X64_MAX 5
+#define HV_CAPS_MAX 8
+
+
+#define HV_HYPERCALL_PARAM_ALIGN sizeof(u64)
+
+
+/* Service definitions */
+
+#define HV_SERVICE_PARENT_PORT (0)
+#define HV_SERVICE_PARENT_CONNECTION (0)
+
+#define HV_SERVICE_CONNECT_RESPONSE_SUCCESS (0)
+#define HV_SERVICE_CONNECT_RESPONSE_INVALID_PARAMETER (1)
+#define HV_SERVICE_CONNECT_RESPONSE_UNKNOWN_SERVICE (2)
+#define HV_SERVICE_CONNECT_RESPONSE_CONNECTION_REJECTED (3)
+
+#define HV_SERVICE_CONNECT_REQUEST_MESSAGE_ID (1)
+#define HV_SERVICE_CONNECT_RESPONSE_MESSAGE_ID (2)
+#define HV_SERVICE_DISCONNECT_REQUEST_MESSAGE_ID (3)
+#define HV_SERVICE_DISCONNECT_RESPONSE_MESSAGE_ID (4)
+#define HV_SERVICE_MAX_MESSAGE_ID (4)
+
+#define HV_SERVICE_PROTOCOL_VERSION (0x0010)
+#define HV_CONNECT_PAYLOAD_BYTE_COUNT 64
+
+/* #define VMBUS_REVISION_NUMBER 6 */
+
+/* Our local vmbus's port and connection id. Anything >0 is fine */
+/* #define VMBUS_PORT_ID 11 */
+
+/* 628180B8-308D-4c5e-B7DB-1BEB62E62EF4 */
+static const uuid_le VMBUS_SERVICE_ID = {
+ .b = {
+ 0xb8, 0x80, 0x81, 0x62, 0x8d, 0x30, 0x5e, 0x4c,
+ 0xb7, 0xdb, 0x1b, 0xeb, 0x62, 0xe6, 0x2e, 0xf4
+ },
+};
+
+
+
+struct hv_context {
+ /* We only support running on top of Hyper-V
+ * So at this point this really can only contain the Hyper-V ID
+ */
+ u64 guestid;
+
+ void *hypercall_page;
+
+ bool synic_initialized;
+
+ void *synic_message_page[NR_CPUS];
+ void *synic_event_page[NR_CPUS];
+ /*
+ * Hypervisor's notion of virtual processor ID is different from
+ * Linux' notion of CPU ID. This information can only be retrieved
+ * in the context of the calling CPU. Setup a map for easy access
+ * to this information:
+ *
+ * vp_index[a] is the Hyper-V's processor ID corresponding to
+ * Linux cpuid 'a'.
+ */
+ u32 vp_index[NR_CPUS];
+ /*
+ * Starting with win8, we can take channel interrupts on any CPU;
+ * we will manage the tasklet that handles events on a per CPU
+ * basis.
+ */
+ struct tasklet_struct *event_dpc[NR_CPUS];
+ /*
+ * To optimize the mapping of relid to channel, maintain
+ * per-cpu list of the channels based on their CPU affinity.
+ */
+ struct list_head percpu_list[NR_CPUS];
+ /*
+ * buffer to post messages to the host.
+ */
+ void *post_msg_page[NR_CPUS];
+ /*
+ * Support PV clockevent device.
+ */
+ struct clock_event_device *clk_evt[NR_CPUS];
+};
+
+extern struct hv_context hv_context;
+
+struct hv_ring_buffer_debug_info {
+ u32 current_interrupt_mask;
+ u32 current_read_index;
+ u32 current_write_index;
+ u32 bytes_avail_toread;
+ u32 bytes_avail_towrite;
+};
+
+/* Hv Interface */
+
+extern int hv_init(void);
+
+extern void hv_cleanup(void);
+
+extern int hv_post_message(union hv_connection_id connection_id,
+ enum hv_message_type message_type,
+ void *payload, size_t payload_size);
+
+extern u16 hv_signal_event(void *con_id);
+
+extern int hv_synic_alloc(void);
+
+extern void hv_synic_free(void);
+
+extern void hv_synic_init(void *irqarg);
+
+extern void hv_synic_cleanup(void *arg);
+
+extern void hv_synic_clockevents_cleanup(void);
+
+/*
+ * Host version information.
+ */
+extern unsigned int host_info_eax;
+extern unsigned int host_info_ebx;
+extern unsigned int host_info_ecx;
+extern unsigned int host_info_edx;
+
+/* Interface */
+
+
+int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info, void *buffer,
+ u32 buflen);
+
+void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
+
+int hv_ringbuffer_write(struct hv_ring_buffer_info *ring_info,
+ struct kvec *kv_list,
+ u32 kv_count, bool *signal);
+
+int hv_ringbuffer_peek(struct hv_ring_buffer_info *ring_info, void *buffer,
+ u32 buflen);
+
+int hv_ringbuffer_read(struct hv_ring_buffer_info *ring_info,
+ void *buffer,
+ u32 buflen,
+ u32 offset, bool *signal);
+
+
+void hv_ringbuffer_get_debuginfo(struct hv_ring_buffer_info *ring_info,
+ struct hv_ring_buffer_debug_info *debug_info);
+
+void hv_begin_read(struct hv_ring_buffer_info *rbi);
+
+u32 hv_end_read(struct hv_ring_buffer_info *rbi);
+
+/*
+ * Maximum channels is determined by the size of the interrupt page
+ * which is PAGE_SIZE. 1/2 of PAGE_SIZE is for send endpoint interrupt
+ * and the other is receive endpoint interrupt
+ */
+#define MAX_NUM_CHANNELS ((PAGE_SIZE >> 1) << 3) /* 16348 channels */
+
+/* The value here must be in multiple of 32 */
+/* TODO: Need to make this configurable */
+#define MAX_NUM_CHANNELS_SUPPORTED 256
+
+
+enum vmbus_connect_state {
+ DISCONNECTED,
+ CONNECTING,
+ CONNECTED,
+ DISCONNECTING
+};
+
+#define MAX_SIZE_CHANNEL_MESSAGE HV_MESSAGE_PAYLOAD_BYTE_COUNT
+
+struct vmbus_connection {
+ enum vmbus_connect_state conn_state;
+
+ atomic_t next_gpadl_handle;
+
+ /*
+ * Represents channel interrupts. Each bit position represents a
+ * channel. When a channel sends an interrupt via VMBUS, it finds its
+ * bit in the sendInterruptPage, set it and calls Hv to generate a port
+ * event. The other end receives the port event and parse the
+ * recvInterruptPage to see which bit is set
+ */
+ void *int_page;
+ void *send_int_page;
+ void *recv_int_page;
+
+ /*
+ * 2 pages - 1st page for parent->child notification and 2nd
+ * is child->parent notification
+ */
+ struct hv_monitor_page *monitor_pages[2];
+ struct list_head chn_msg_list;
+ spinlock_t channelmsg_lock;
+
+ /* List of channels */
+ struct list_head chn_list;
+ spinlock_t channel_lock;
+
+ struct workqueue_struct *work_queue;
+};
+
+
+struct vmbus_msginfo {
+ /* Bookkeeping stuff */
+ struct list_head msglist_entry;
+
+ /* The message itself */
+ unsigned char msg[0];
+};
+
+
+extern struct vmbus_connection vmbus_connection;
+
+enum vmbus_message_handler_type {
+ /* The related handler can sleep. */
+ VMHT_BLOCKING = 0,
+
+ /* The related handler must NOT sleep. */
+ VMHT_NON_BLOCKING = 1,
+};
+
+struct vmbus_channel_message_table_entry {
+ enum vmbus_channel_message_type message_type;
+ enum vmbus_message_handler_type handler_type;
+ void (*message_handler)(struct vmbus_channel_message_header *msg);
+};
+
+extern struct vmbus_channel_message_table_entry
+ channel_message_table[CHANNELMSG_COUNT];
+
+/* General vmbus interface */
+
+struct hv_device *vmbus_device_create(const uuid_le *type,
+ const uuid_le *instance,
+ struct vmbus_channel *channel);
+
+int vmbus_device_register(struct hv_device *child_device_obj);
+void vmbus_device_unregister(struct hv_device *device_obj);
+
+/* static void */
+/* VmbusChildDeviceDestroy( */
+/* struct hv_device *); */
+
+struct vmbus_channel *relid2channel(u32 relid);
+
+void vmbus_free_channels(void);
+
+/* Connection interface */
+
+int vmbus_connect(void);
+void vmbus_disconnect(void);
+
+int vmbus_post_msg(void *buffer, size_t buflen);
+
+int vmbus_set_event(struct vmbus_channel *channel);
+
+void vmbus_on_event(unsigned long data);
+
+int hv_fcopy_init(struct hv_util_service *);
+void hv_fcopy_deinit(void);
+void hv_fcopy_onchannelcallback(void *);
+
+
+#endif /* _HYPERV_VMBUS_H */
diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
new file mode 100644
index 000000000..6361d124f
--- /dev/null
+++ b/drivers/hv/ring_buffer.c
@@ -0,0 +1,566 @@
+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ * Haiyang Zhang <haiyangz@microsoft.com>
+ * Hank Janssen <hjanssen@microsoft.com>
+ * K. Y. Srinivasan <kys@microsoft.com>
+ *
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/hyperv.h>
+#include <linux/uio.h>
+
+#include "hyperv_vmbus.h"
+
+void hv_begin_read(struct hv_ring_buffer_info *rbi)
+{
+ rbi->ring_buffer->interrupt_mask = 1;
+ mb();
+}
+
+u32 hv_end_read(struct hv_ring_buffer_info *rbi)
+{
+ u32 read;
+ u32 write;
+
+ rbi->ring_buffer->interrupt_mask = 0;
+ mb();
+
+ /*
+ * Now check to see if the ring buffer is still empty.
+ * If it is not, we raced and we need to process new
+ * incoming messages.
+ */
+ hv_get_ringbuffer_availbytes(rbi, &read, &write);
+
+ return read;
+}
+
+/*
+ * When we write to the ring buffer, check if the host needs to
+ * be signaled. Here is the details of this protocol:
+ *
+ * 1. The host guarantees that while it is draining the
+ * ring buffer, it will set the interrupt_mask to
+ * indicate it does not need to be interrupted when
+ * new data is placed.
+ *
+ * 2. The host guarantees that it will completely drain
+ * the ring buffer before exiting the read loop. Further,
+ * once the ring buffer is empty, it will clear the
+ * interrupt_mask and re-check to see if new data has
+ * arrived.
+ */
+
+static bool hv_need_to_signal(u32 old_write, struct hv_ring_buffer_info *rbi)
+{
+ mb();
+ if (rbi->ring_buffer->interrupt_mask)
+ return false;
+
+ /* check interrupt_mask before read_index */
+ rmb();
+ /*
+ * This is the only case we need to signal when the
+ * ring transitions from being empty to non-empty.
+ */
+ if (old_write == rbi->ring_buffer->read_index)
+ return true;
+
+ return false;
+}
+
+/*
+ * To optimize the flow management on the send-side,
+ * when the sender is blocked because of lack of
+ * sufficient space in the ring buffer, potential the
+ * consumer of the ring buffer can signal the producer.
+ * This is controlled by the following parameters:
+ *
+ * 1. pending_send_sz: This is the size in bytes that the
+ * producer is trying to send.
+ * 2. The feature bit feat_pending_send_sz set to indicate if
+ * the consumer of the ring will signal when the ring
+ * state transitions from being full to a state where
+ * there is room for the producer to send the pending packet.
+ */
+
+static bool hv_need_to_signal_on_read(u32 old_rd,
+ struct hv_ring_buffer_info *rbi)
+{
+ u32 prev_write_sz;
+ u32 cur_write_sz;
+ u32 r_size;
+ u32 write_loc = rbi->ring_buffer->write_index;
+ u32 read_loc = rbi->ring_buffer->read_index;
+ u32 pending_sz = rbi->ring_buffer->pending_send_sz;
+
+ /*
+ * If the other end is not blocked on write don't bother.
+ */
+ if (pending_sz == 0)
+ return false;
+
+ r_size = rbi->ring_datasize;
+ cur_write_sz = write_loc >= read_loc ? r_size - (write_loc - read_loc) :
+ read_loc - write_loc;
+
+ prev_write_sz = write_loc >= old_rd ? r_size - (write_loc - old_rd) :
+ old_rd - write_loc;
+
+
+ if ((prev_write_sz < pending_sz) && (cur_write_sz >= pending_sz))
+ return true;
+
+ return false;
+}
+
+/*
+ * hv_get_next_write_location()
+ *
+ * Get the next write location for the specified ring buffer
+ *
+ */
+static inline u32
+hv_get_next_write_location(struct hv_ring_buffer_info *ring_info)
+{
+ u32 next = ring_info->ring_buffer->write_index;
+
+ return next;
+}
+
+/*
+ * hv_set_next_write_location()
+ *
+ * Set the next write location for the specified ring buffer
+ *
+ */
+static inline void
+hv_set_next_write_location(struct hv_ring_buffer_info *ring_info,
+ u32 next_write_location)
+{
+ ring_info->ring_buffer->write_index = next_write_location;
+}
+
+/*
+ * hv_get_next_read_location()
+ *
+ * Get the next read location for the specified ring buffer
+ */
+static inline u32
+hv_get_next_read_location(struct hv_ring_buffer_info *ring_info)
+{
+ u32 next = ring_info->ring_buffer->read_index;
+
+ return next;
+}
+
+/*
+ * hv_get_next_readlocation_withoffset()
+ *
+ * Get the next read location + offset for the specified ring buffer.
+ * This allows the caller to skip
+ */
+static inline u32
+hv_get_next_readlocation_withoffset(struct hv_ring_buffer_info *ring_info,
+ u32 offset)
+{
+ u32 next = ring_info->ring_buffer->read_index;
+
+ next += offset;
+ next %= ring_info->ring_datasize;
+
+ return next;
+}
+
+/*
+ *
+ * hv_set_next_read_location()
+ *
+ * Set the next read location for the specified ring buffer
+ *
+ */
+static inline void
+hv_set_next_read_location(struct hv_ring_buffer_info *ring_info,
+ u32 next_read_location)
+{
+ ring_info->ring_buffer->read_index = next_read_location;
+}
+
+
+/*
+ *
+ * hv_get_ring_buffer()
+ *
+ * Get the start of the ring buffer
+ */
+static inline void *
+hv_get_ring_buffer(struct hv_ring_buffer_info *ring_info)
+{
+ return (void *)ring_info->ring_buffer->buffer;
+}
+
+
+/*
+ *
+ * hv_get_ring_buffersize()
+ *
+ * Get the size of the ring buffer
+ */
+static inline u32
+hv_get_ring_buffersize(struct hv_ring_buffer_info *ring_info)
+{
+ return ring_info->ring_datasize;
+}
+
+/*
+ *
+ * hv_get_ring_bufferindices()
+ *
+ * Get the read and write indices as u64 of the specified ring buffer
+ *
+ */
+static inline u64
+hv_get_ring_bufferindices(struct hv_ring_buffer_info *ring_info)
+{
+ return (u64)ring_info->ring_buffer->write_index << 32;
+}
+
+/*
+ *
+ * hv_copyfrom_ringbuffer()
+ *
+ * Helper routine to copy to source from ring buffer.
+ * Assume there is enough room. Handles wrap-around in src case only!!
+ *
+ */
+static u32 hv_copyfrom_ringbuffer(
+ struct hv_ring_buffer_info *ring_info,
+ void *dest,
+ u32 destlen,
+ u32 start_read_offset)
+{
+ void *ring_buffer = hv_get_ring_buffer(ring_info);
+ u32 ring_buffer_size = hv_get_ring_buffersize(ring_info);
+
+ u32 frag_len;
+
+ /* wrap-around detected at the src */
+ if (destlen > ring_buffer_size - start_read_offset) {
+ frag_len = ring_buffer_size - start_read_offset;
+
+ memcpy(dest, ring_buffer + start_read_offset, frag_len);
+ memcpy(dest + frag_len, ring_buffer, destlen - frag_len);
+ } else
+
+ memcpy(dest, ring_buffer + start_read_offset, destlen);
+
+
+ start_read_offset += destlen;
+ start_read_offset %= ring_buffer_size;
+
+ return start_read_offset;
+}
+
+
+/*
+ *
+ * hv_copyto_ringbuffer()
+ *
+ * Helper routine to copy from source to ring buffer.
+ * Assume there is enough room. Handles wrap-around in dest case only!!
+ *
+ */
+static u32 hv_copyto_ringbuffer(
+ struct hv_ring_buffer_info *ring_info,
+ u32 start_write_offset,
+ void *src,
+ u32 srclen)
+{
+ void *ring_buffer = hv_get_ring_buffer(ring_info);
+ u32 ring_buffer_size = hv_get_ring_buffersize(ring_info);
+ u32 frag_len;
+
+ /* wrap-around detected! */
+ if (srclen > ring_buffer_size - start_write_offset) {
+ frag_len = ring_buffer_size - start_write_offset;
+ memcpy(ring_buffer + start_write_offset, src, frag_len);
+ memcpy(ring_buffer, src + frag_len, srclen - frag_len);
+ } else
+ memcpy(ring_buffer + start_write_offset, src, srclen);
+
+ start_write_offset += srclen;
+ start_write_offset %= ring_buffer_size;
+
+ return start_write_offset;
+}
+
+/*
+ *
+ * hv_ringbuffer_get_debuginfo()
+ *
+ * Get various debug metrics for the specified ring buffer
+ *
+ */
+void hv_ringbuffer_get_debuginfo(struct hv_ring_buffer_info *ring_info,
+ struct hv_ring_buffer_debug_info *debug_info)
+{
+ u32 bytes_avail_towrite;
+ u32 bytes_avail_toread;
+
+ if (ring_info->ring_buffer) {
+ hv_get_ringbuffer_availbytes(ring_info,
+ &bytes_avail_toread,
+ &bytes_avail_towrite);
+
+ debug_info->bytes_avail_toread = bytes_avail_toread;
+ debug_info->bytes_avail_towrite = bytes_avail_towrite;
+ debug_info->current_read_index =
+ ring_info->ring_buffer->read_index;
+ debug_info->current_write_index =
+ ring_info->ring_buffer->write_index;
+ debug_info->current_interrupt_mask =
+ ring_info->ring_buffer->interrupt_mask;
+ }
+}
+
+/*
+ *
+ * hv_ringbuffer_init()
+ *
+ *Initialize the ring buffer
+ *
+ */
+int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
+ void *buffer, u32 buflen)
+{
+ if (sizeof(struct hv_ring_buffer) != PAGE_SIZE)
+ return -EINVAL;
+
+ memset(ring_info, 0, sizeof(struct hv_ring_buffer_info));
+
+ ring_info->ring_buffer = (struct hv_ring_buffer *)buffer;
+ ring_info->ring_buffer->read_index =
+ ring_info->ring_buffer->write_index = 0;
+
+ /*
+ * Set the feature bit for enabling flow control.
+ */
+ ring_info->ring_buffer->feature_bits.value = 1;
+
+ ring_info->ring_size = buflen;
+ ring_info->ring_datasize = buflen - sizeof(struct hv_ring_buffer);
+
+ spin_lock_init(&ring_info->ring_lock);
+
+ return 0;
+}
+
+/*
+ *
+ * hv_ringbuffer_cleanup()
+ *
+ * Cleanup the ring buffer
+ *
+ */
+void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info)
+{
+}
+
+/*
+ *
+ * hv_ringbuffer_write()
+ *
+ * Write to the ring buffer
+ *
+ */
+int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
+ struct kvec *kv_list, u32 kv_count, bool *signal)
+{
+ int i = 0;
+ u32 bytes_avail_towrite;
+ u32 bytes_avail_toread;
+ u32 totalbytes_towrite = 0;
+
+ u32 next_write_location;
+ u32 old_write;
+ u64 prev_indices = 0;
+ unsigned long flags;
+
+ for (i = 0; i < kv_count; i++)
+ totalbytes_towrite += kv_list[i].iov_len;
+
+ totalbytes_towrite += sizeof(u64);
+
+ spin_lock_irqsave(&outring_info->ring_lock, flags);
+
+ hv_get_ringbuffer_availbytes(outring_info,
+ &bytes_avail_toread,
+ &bytes_avail_towrite);
+
+
+ /* If there is only room for the packet, assume it is full. */
+ /* Otherwise, the next time around, we think the ring buffer */
+ /* is empty since the read index == write index */
+ if (bytes_avail_towrite <= totalbytes_towrite) {
+ spin_unlock_irqrestore(&outring_info->ring_lock, flags);
+ return -EAGAIN;
+ }
+
+ /* Write to the ring buffer */
+ next_write_location = hv_get_next_write_location(outring_info);
+
+ old_write = next_write_location;
+
+ for (i = 0; i < kv_count; i++) {
+ next_write_location = hv_copyto_ringbuffer(outring_info,
+ next_write_location,
+ kv_list[i].iov_base,
+ kv_list[i].iov_len);
+ }
+
+ /* Set previous packet start */
+ prev_indices = hv_get_ring_bufferindices(outring_info);
+
+ next_write_location = hv_copyto_ringbuffer(outring_info,
+ next_write_location,
+ &prev_indices,
+ sizeof(u64));
+
+ /* Issue a full memory barrier before updating the write index */
+ mb();
+
+ /* Now, update the write location */
+ hv_set_next_write_location(outring_info, next_write_location);
+
+
+ spin_unlock_irqrestore(&outring_info->ring_lock, flags);
+
+ *signal = hv_need_to_signal(old_write, outring_info);
+ return 0;
+}
+
+
+/*
+ *
+ * hv_ringbuffer_peek()
+ *
+ * Read without advancing the read index
+ *
+ */
+int hv_ringbuffer_peek(struct hv_ring_buffer_info *Inring_info,
+ void *Buffer, u32 buflen)
+{
+ u32 bytes_avail_towrite;
+ u32 bytes_avail_toread;
+ u32 next_read_location = 0;
+ unsigned long flags;
+
+ spin_lock_irqsave(&Inring_info->ring_lock, flags);
+
+ hv_get_ringbuffer_availbytes(Inring_info,
+ &bytes_avail_toread,
+ &bytes_avail_towrite);
+
+ /* Make sure there is something to read */
+ if (bytes_avail_toread < buflen) {
+
+ spin_unlock_irqrestore(&Inring_info->ring_lock, flags);
+
+ return -EAGAIN;
+ }
+
+ /* Convert to byte offset */
+ next_read_location = hv_get_next_read_location(Inring_info);
+
+ next_read_location = hv_copyfrom_ringbuffer(Inring_info,
+ Buffer,
+ buflen,
+ next_read_location);
+
+ spin_unlock_irqrestore(&Inring_info->ring_lock, flags);
+
+ return 0;
+}
+
+
+/*
+ *
+ * hv_ringbuffer_read()
+ *
+ * Read and advance the read index
+ *
+ */
+int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info, void *buffer,
+ u32 buflen, u32 offset, bool *signal)
+{
+ u32 bytes_avail_towrite;
+ u32 bytes_avail_toread;
+ u32 next_read_location = 0;
+ u64 prev_indices = 0;
+ unsigned long flags;
+ u32 old_read;
+
+ if (buflen <= 0)
+ return -EINVAL;
+
+ spin_lock_irqsave(&inring_info->ring_lock, flags);
+
+ hv_get_ringbuffer_availbytes(inring_info,
+ &bytes_avail_toread,
+ &bytes_avail_towrite);
+
+ old_read = bytes_avail_toread;
+
+ /* Make sure there is something to read */
+ if (bytes_avail_toread < buflen) {
+ spin_unlock_irqrestore(&inring_info->ring_lock, flags);
+
+ return -EAGAIN;
+ }
+
+ next_read_location =
+ hv_get_next_readlocation_withoffset(inring_info, offset);
+
+ next_read_location = hv_copyfrom_ringbuffer(inring_info,
+ buffer,
+ buflen,
+ next_read_location);
+
+ next_read_location = hv_copyfrom_ringbuffer(inring_info,
+ &prev_indices,
+ sizeof(u64),
+ next_read_location);
+
+ /* Make sure all reads are done before we update the read index since */
+ /* the writer may start writing to the read area once the read index */
+ /*is updated */
+ mb();
+
+ /* Update the read index */
+ hv_set_next_read_location(inring_info, next_read_location);
+
+ spin_unlock_irqrestore(&inring_info->ring_lock, flags);
+
+ *signal = hv_need_to_signal_on_read(old_read, inring_info);
+
+ return 0;
+}
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
new file mode 100644
index 000000000..c85235e9f
--- /dev/null
+++ b/drivers/hv/vmbus_drv.c
@@ -0,0 +1,1114 @@
+/*
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ * Haiyang Zhang <haiyangz@microsoft.com>
+ * Hank Janssen <hjanssen@microsoft.com>
+ * K. Y. Srinivasan <kys@microsoft.com>
+ *
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/sysctl.h>
+#include <linux/slab.h>
+#include <linux/acpi.h>
+#include <linux/completion.h>
+#include <linux/hyperv.h>
+#include <linux/kernel_stat.h>
+#include <linux/clockchips.h>
+#include <linux/cpu.h>
+#include <asm/hyperv.h>
+#include <asm/hypervisor.h>
+#include <asm/mshyperv.h>
+#include <linux/notifier.h>
+#include <linux/ptrace.h>
+#include "hyperv_vmbus.h"
+
+static struct acpi_device *hv_acpi_dev;
+
+static struct tasklet_struct msg_dpc;
+static struct completion probe_event;
+static int irq;
+
+
+static int hyperv_panic_event(struct notifier_block *nb,
+ unsigned long event, void *ptr)
+{
+ struct pt_regs *regs;
+
+ regs = current_pt_regs();
+
+ wrmsrl(HV_X64_MSR_CRASH_P0, regs->ip);
+ wrmsrl(HV_X64_MSR_CRASH_P1, regs->ax);
+ wrmsrl(HV_X64_MSR_CRASH_P2, regs->bx);
+ wrmsrl(HV_X64_MSR_CRASH_P3, regs->cx);
+ wrmsrl(HV_X64_MSR_CRASH_P4, regs->dx);
+
+ /*
+ * Let Hyper-V know there is crash data available
+ */
+ wrmsrl(HV_X64_MSR_CRASH_CTL, HV_CRASH_CTL_CRASH_NOTIFY);
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block hyperv_panic_block = {
+ .notifier_call = hyperv_panic_event,
+};
+
+struct resource hyperv_mmio = {
+ .name = "hyperv mmio",
+ .flags = IORESOURCE_MEM,
+};
+EXPORT_SYMBOL_GPL(hyperv_mmio);
+
+static int vmbus_exists(void)
+{
+ if (hv_acpi_dev == NULL)
+ return -ENODEV;
+
+ return 0;
+}
+
+#define VMBUS_ALIAS_LEN ((sizeof((struct hv_vmbus_device_id *)0)->guid) * 2)
+static void print_alias_name(struct hv_device *hv_dev, char *alias_name)
+{
+ int i;
+ for (i = 0; i < VMBUS_ALIAS_LEN; i += 2)
+ sprintf(&alias_name[i], "%02x", hv_dev->dev_type.b[i/2]);
+}
+
+static u8 channel_monitor_group(struct vmbus_channel *channel)
+{
+ return (u8)channel->offermsg.monitorid / 32;
+}
+
+static u8 channel_monitor_offset(struct vmbus_channel *channel)
+{
+ return (u8)channel->offermsg.monitorid % 32;
+}
+
+static u32 channel_pending(struct vmbus_channel *channel,
+ struct hv_monitor_page *monitor_page)
+{
+ u8 monitor_group = channel_monitor_group(channel);
+ return monitor_page->trigger_group[monitor_group].pending;
+}
+
+static u32 channel_latency(struct vmbus_channel *channel,
+ struct hv_monitor_page *monitor_page)
+{
+ u8 monitor_group = channel_monitor_group(channel);
+ u8 monitor_offset = channel_monitor_offset(channel);
+ return monitor_page->latency[monitor_group][monitor_offset];
+}
+
+static u32 channel_conn_id(struct vmbus_channel *channel,
+ struct hv_monitor_page *monitor_page)
+{
+ u8 monitor_group = channel_monitor_group(channel);
+ u8 monitor_offset = channel_monitor_offset(channel);
+ return monitor_page->parameter[monitor_group][monitor_offset].connectionid.u.id;
+}
+
+static ssize_t id_show(struct device *dev, struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ return sprintf(buf, "%d\n", hv_dev->channel->offermsg.child_relid);
+}
+static DEVICE_ATTR_RO(id);
+
+static ssize_t state_show(struct device *dev, struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ return sprintf(buf, "%d\n", hv_dev->channel->state);
+}
+static DEVICE_ATTR_RO(state);
+
+static ssize_t monitor_id_show(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ return sprintf(buf, "%d\n", hv_dev->channel->offermsg.monitorid);
+}
+static DEVICE_ATTR_RO(monitor_id);
+
+static ssize_t class_id_show(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ return sprintf(buf, "{%pUl}\n",
+ hv_dev->channel->offermsg.offer.if_type.b);
+}
+static DEVICE_ATTR_RO(class_id);
+
+static ssize_t device_id_show(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ return sprintf(buf, "{%pUl}\n",
+ hv_dev->channel->offermsg.offer.if_instance.b);
+}
+static DEVICE_ATTR_RO(device_id);
+
+static ssize_t modalias_show(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+ char alias_name[VMBUS_ALIAS_LEN + 1];
+
+ print_alias_name(hv_dev, alias_name);
+ return sprintf(buf, "vmbus:%s\n", alias_name);
+}
+static DEVICE_ATTR_RO(modalias);
+
+static ssize_t server_monitor_pending_show(struct device *dev,
+ struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ return sprintf(buf, "%d\n",
+ channel_pending(hv_dev->channel,
+ vmbus_connection.monitor_pages[1]));
+}
+static DEVICE_ATTR_RO(server_monitor_pending);
+
+static ssize_t client_monitor_pending_show(struct device *dev,
+ struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ return sprintf(buf, "%d\n",
+ channel_pending(hv_dev->channel,
+ vmbus_connection.monitor_pages[1]));
+}
+static DEVICE_ATTR_RO(client_monitor_pending);
+
+static ssize_t server_monitor_latency_show(struct device *dev,
+ struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ return sprintf(buf, "%d\n",
+ channel_latency(hv_dev->channel,
+ vmbus_connection.monitor_pages[0]));
+}
+static DEVICE_ATTR_RO(server_monitor_latency);
+
+static ssize_t client_monitor_latency_show(struct device *dev,
+ struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ return sprintf(buf, "%d\n",
+ channel_latency(hv_dev->channel,
+ vmbus_connection.monitor_pages[1]));
+}
+static DEVICE_ATTR_RO(client_monitor_latency);
+
+static ssize_t server_monitor_conn_id_show(struct device *dev,
+ struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ return sprintf(buf, "%d\n",
+ channel_conn_id(hv_dev->channel,
+ vmbus_connection.monitor_pages[0]));
+}
+static DEVICE_ATTR_RO(server_monitor_conn_id);
+
+static ssize_t client_monitor_conn_id_show(struct device *dev,
+ struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ return sprintf(buf, "%d\n",
+ channel_conn_id(hv_dev->channel,
+ vmbus_connection.monitor_pages[1]));
+}
+static DEVICE_ATTR_RO(client_monitor_conn_id);
+
+static ssize_t out_intr_mask_show(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+ struct hv_ring_buffer_debug_info outbound;
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
+ return sprintf(buf, "%d\n", outbound.current_interrupt_mask);
+}
+static DEVICE_ATTR_RO(out_intr_mask);
+
+static ssize_t out_read_index_show(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+ struct hv_ring_buffer_debug_info outbound;
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
+ return sprintf(buf, "%d\n", outbound.current_read_index);
+}
+static DEVICE_ATTR_RO(out_read_index);
+
+static ssize_t out_write_index_show(struct device *dev,
+ struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+ struct hv_ring_buffer_debug_info outbound;
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
+ return sprintf(buf, "%d\n", outbound.current_write_index);
+}
+static DEVICE_ATTR_RO(out_write_index);
+
+static ssize_t out_read_bytes_avail_show(struct device *dev,
+ struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+ struct hv_ring_buffer_debug_info outbound;
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
+ return sprintf(buf, "%d\n", outbound.bytes_avail_toread);
+}
+static DEVICE_ATTR_RO(out_read_bytes_avail);
+
+static ssize_t out_write_bytes_avail_show(struct device *dev,
+ struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+ struct hv_ring_buffer_debug_info outbound;
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ hv_ringbuffer_get_debuginfo(&hv_dev->channel->outbound, &outbound);
+ return sprintf(buf, "%d\n", outbound.bytes_avail_towrite);
+}
+static DEVICE_ATTR_RO(out_write_bytes_avail);
+
+static ssize_t in_intr_mask_show(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+ struct hv_ring_buffer_debug_info inbound;
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
+ return sprintf(buf, "%d\n", inbound.current_interrupt_mask);
+}
+static DEVICE_ATTR_RO(in_intr_mask);
+
+static ssize_t in_read_index_show(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+ struct hv_ring_buffer_debug_info inbound;
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
+ return sprintf(buf, "%d\n", inbound.current_read_index);
+}
+static DEVICE_ATTR_RO(in_read_index);
+
+static ssize_t in_write_index_show(struct device *dev,
+ struct device_attribute *dev_attr, char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+ struct hv_ring_buffer_debug_info inbound;
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
+ return sprintf(buf, "%d\n", inbound.current_write_index);
+}
+static DEVICE_ATTR_RO(in_write_index);
+
+static ssize_t in_read_bytes_avail_show(struct device *dev,
+ struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+ struct hv_ring_buffer_debug_info inbound;
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
+ return sprintf(buf, "%d\n", inbound.bytes_avail_toread);
+}
+static DEVICE_ATTR_RO(in_read_bytes_avail);
+
+static ssize_t in_write_bytes_avail_show(struct device *dev,
+ struct device_attribute *dev_attr,
+ char *buf)
+{
+ struct hv_device *hv_dev = device_to_hv_device(dev);
+ struct hv_ring_buffer_debug_info inbound;
+
+ if (!hv_dev->channel)
+ return -ENODEV;
+ hv_ringbuffer_get_debuginfo(&hv_dev->channel->inbound, &inbound);
+ return sprintf(buf, "%d\n", inbound.bytes_avail_towrite);
+}
+static DEVICE_ATTR_RO(in_write_bytes_avail);
+
+/* Set up per device attributes in /sys/bus/vmbus/devices/<bus device> */
+static struct attribute *vmbus_attrs[] = {
+ &dev_attr_id.attr,
+ &dev_attr_state.attr,
+ &dev_attr_monitor_id.attr,
+ &dev_attr_class_id.attr,
+ &dev_attr_device_id.attr,
+ &dev_attr_modalias.attr,
+ &dev_attr_server_monitor_pending.attr,
+ &dev_attr_client_monitor_pending.attr,
+ &dev_attr_server_monitor_latency.attr,
+ &dev_attr_client_monitor_latency.attr,
+ &dev_attr_server_monitor_conn_id.attr,
+ &dev_attr_client_monitor_conn_id.attr,
+ &dev_attr_out_intr_mask.attr,
+ &dev_attr_out_read_index.attr,
+ &dev_attr_out_write_index.attr,
+ &dev_attr_out_read_bytes_avail.attr,
+ &dev_attr_out_write_bytes_avail.attr,
+ &dev_attr_in_intr_mask.attr,
+ &dev_attr_in_read_index.attr,
+ &dev_attr_in_write_index.attr,
+ &dev_attr_in_read_bytes_avail.attr,
+ &dev_attr_in_write_bytes_avail.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(vmbus);
+
+/*
+ * vmbus_uevent - add uevent for our device
+ *
+ * This routine is invoked when a device is added or removed on the vmbus to
+ * generate a uevent to udev in the userspace. The udev will then look at its
+ * rule and the uevent generated here to load the appropriate driver
+ *
+ * The alias string will be of the form vmbus:guid where guid is the string
+ * representation of the device guid (each byte of the guid will be
+ * represented with two hex characters.
+ */
+static int vmbus_uevent(struct device *device, struct kobj_uevent_env *env)
+{
+ struct hv_device *dev = device_to_hv_device(device);
+ int ret;
+ char alias_name[VMBUS_ALIAS_LEN + 1];
+
+ print_alias_name(dev, alias_name);
+ ret = add_uevent_var(env, "MODALIAS=vmbus:%s", alias_name);
+ return ret;
+}
+
+static const uuid_le null_guid;
+
+static inline bool is_null_guid(const __u8 *guid)
+{
+ if (memcmp(guid, &null_guid, sizeof(uuid_le)))
+ return false;
+ return true;
+}
+
+/*
+ * Return a matching hv_vmbus_device_id pointer.
+ * If there is no match, return NULL.
+ */
+static const struct hv_vmbus_device_id *hv_vmbus_get_id(
+ const struct hv_vmbus_device_id *id,
+ const __u8 *guid)
+{
+ for (; !is_null_guid(id->guid); id++)
+ if (!memcmp(&id->guid, guid, sizeof(uuid_le)))
+ return id;
+
+ return NULL;
+}
+
+
+
+/*
+ * vmbus_match - Attempt to match the specified device to the specified driver
+ */
+static int vmbus_match(struct device *device, struct device_driver *driver)
+{
+ struct hv_driver *drv = drv_to_hv_drv(driver);
+ struct hv_device *hv_dev = device_to_hv_device(device);
+
+ if (hv_vmbus_get_id(drv->id_table, hv_dev->dev_type.b))
+ return 1;
+
+ return 0;
+}
+
+/*
+ * vmbus_probe - Add the new vmbus's child device
+ */
+static int vmbus_probe(struct device *child_device)
+{
+ int ret = 0;
+ struct hv_driver *drv =
+ drv_to_hv_drv(child_device->driver);
+ struct hv_device *dev = device_to_hv_device(child_device);
+ const struct hv_vmbus_device_id *dev_id;
+
+ dev_id = hv_vmbus_get_id(drv->id_table, dev->dev_type.b);
+ if (drv->probe) {
+ ret = drv->probe(dev, dev_id);
+ if (ret != 0)
+ pr_err("probe failed for device %s (%d)\n",
+ dev_name(child_device), ret);
+
+ } else {
+ pr_err("probe not set for driver %s\n",
+ dev_name(child_device));
+ ret = -ENODEV;
+ }
+ return ret;
+}
+
+/*
+ * vmbus_remove - Remove a vmbus device
+ */
+static int vmbus_remove(struct device *child_device)
+{
+ struct hv_driver *drv;
+ struct hv_device *dev = device_to_hv_device(child_device);
+ u32 relid = dev->channel->offermsg.child_relid;
+
+ if (child_device->driver) {
+ drv = drv_to_hv_drv(child_device->driver);
+ if (drv->remove)
+ drv->remove(dev);
+ else {
+ hv_process_channel_removal(dev->channel, relid);
+ pr_err("remove not set for driver %s\n",
+ dev_name(child_device));
+ }
+ } else {
+ /*
+ * We don't have a driver for this device; deal with the
+ * rescind message by removing the channel.
+ */
+ hv_process_channel_removal(dev->channel, relid);
+ }
+
+ return 0;
+}
+
+
+/*
+ * vmbus_shutdown - Shutdown a vmbus device
+ */
+static void vmbus_shutdown(struct device *child_device)
+{
+ struct hv_driver *drv;
+ struct hv_device *dev = device_to_hv_device(child_device);
+
+
+ /* The device may not be attached yet */
+ if (!child_device->driver)
+ return;
+
+ drv = drv_to_hv_drv(child_device->driver);
+
+ if (drv->shutdown)
+ drv->shutdown(dev);
+
+ return;
+}
+
+
+/*
+ * vmbus_device_release - Final callback release of the vmbus child device
+ */
+static void vmbus_device_release(struct device *device)
+{
+ struct hv_device *hv_dev = device_to_hv_device(device);
+
+ kfree(hv_dev);
+
+}
+
+/* The one and only one */
+static struct bus_type hv_bus = {
+ .name = "vmbus",
+ .match = vmbus_match,
+ .shutdown = vmbus_shutdown,
+ .remove = vmbus_remove,
+ .probe = vmbus_probe,
+ .uevent = vmbus_uevent,
+ .dev_groups = vmbus_groups,
+};
+
+struct onmessage_work_context {
+ struct work_struct work;
+ struct hv_message msg;
+};
+
+static void vmbus_onmessage_work(struct work_struct *work)
+{
+ struct onmessage_work_context *ctx;
+
+ /* Do not process messages if we're in DISCONNECTED state */
+ if (vmbus_connection.conn_state == DISCONNECTED)
+ return;
+
+ ctx = container_of(work, struct onmessage_work_context,
+ work);
+ vmbus_onmessage(&ctx->msg);
+ kfree(ctx);
+}
+
+static void hv_process_timer_expiration(struct hv_message *msg, int cpu)
+{
+ struct clock_event_device *dev = hv_context.clk_evt[cpu];
+
+ if (dev->event_handler)
+ dev->event_handler(dev);
+
+ msg->header.message_type = HVMSG_NONE;
+
+ /*
+ * Make sure the write to MessageType (ie set to
+ * HVMSG_NONE) happens before we read the
+ * MessagePending and EOMing. Otherwise, the EOMing
+ * will not deliver any more messages since there is
+ * no empty slot
+ */
+ mb();
+
+ if (msg->header.message_flags.msg_pending) {
+ /*
+ * This will cause message queue rescan to
+ * possibly deliver another msg from the
+ * hypervisor
+ */
+ wrmsrl(HV_X64_MSR_EOM, 0);
+ }
+}
+
+static void vmbus_on_msg_dpc(unsigned long data)
+{
+ int cpu = smp_processor_id();
+ void *page_addr = hv_context.synic_message_page[cpu];
+ struct hv_message *msg = (struct hv_message *)page_addr +
+ VMBUS_MESSAGE_SINT;
+ struct vmbus_channel_message_header *hdr;
+ struct vmbus_channel_message_table_entry *entry;
+ struct onmessage_work_context *ctx;
+
+ while (1) {
+ if (msg->header.message_type == HVMSG_NONE)
+ /* no msg */
+ break;
+
+ hdr = (struct vmbus_channel_message_header *)msg->u.payload;
+
+ if (hdr->msgtype >= CHANNELMSG_COUNT) {
+ WARN_ONCE(1, "unknown msgtype=%d\n", hdr->msgtype);
+ goto msg_handled;
+ }
+
+ entry = &channel_message_table[hdr->msgtype];
+ if (entry->handler_type == VMHT_BLOCKING) {
+ ctx = kmalloc(sizeof(*ctx), GFP_ATOMIC);
+ if (ctx == NULL)
+ continue;
+
+ INIT_WORK(&ctx->work, vmbus_onmessage_work);
+ memcpy(&ctx->msg, msg, sizeof(*msg));
+
+ queue_work(vmbus_connection.work_queue, &ctx->work);
+ } else
+ entry->message_handler(hdr);
+
+msg_handled:
+ msg->header.message_type = HVMSG_NONE;
+
+ /*
+ * Make sure the write to MessageType (ie set to
+ * HVMSG_NONE) happens before we read the
+ * MessagePending and EOMing. Otherwise, the EOMing
+ * will not deliver any more messages since there is
+ * no empty slot
+ */
+ mb();
+
+ if (msg->header.message_flags.msg_pending) {
+ /*
+ * This will cause message queue rescan to
+ * possibly deliver another msg from the
+ * hypervisor
+ */
+ wrmsrl(HV_X64_MSR_EOM, 0);
+ }
+ }
+}
+
+static void vmbus_isr(void)
+{
+ int cpu = smp_processor_id();
+ void *page_addr;
+ struct hv_message *msg;
+ union hv_synic_event_flags *event;
+ bool handled = false;
+
+ page_addr = hv_context.synic_event_page[cpu];
+ if (page_addr == NULL)
+ return;
+
+ event = (union hv_synic_event_flags *)page_addr +
+ VMBUS_MESSAGE_SINT;
+ /*
+ * Check for events before checking for messages. This is the order
+ * in which events and messages are checked in Windows guests on
+ * Hyper-V, and the Windows team suggested we do the same.
+ */
+
+ if ((vmbus_proto_version == VERSION_WS2008) ||
+ (vmbus_proto_version == VERSION_WIN7)) {
+
+ /* Since we are a child, we only need to check bit 0 */
+ if (sync_test_and_clear_bit(0,
+ (unsigned long *) &event->flags32[0])) {
+ handled = true;
+ }
+ } else {
+ /*
+ * Our host is win8 or above. The signaling mechanism
+ * has changed and we can directly look at the event page.
+ * If bit n is set then we have an interrup on the channel
+ * whose id is n.
+ */
+ handled = true;
+ }
+
+ if (handled)
+ tasklet_schedule(hv_context.event_dpc[cpu]);
+
+
+ page_addr = hv_context.synic_message_page[cpu];
+ msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT;
+
+ /* Check if there are actual msgs to be processed */
+ if (msg->header.message_type != HVMSG_NONE) {
+ if (msg->header.message_type == HVMSG_TIMER_EXPIRED)
+ hv_process_timer_expiration(msg, cpu);
+ else
+ tasklet_schedule(&msg_dpc);
+ }
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static int hyperv_cpu_disable(void)
+{
+ return -ENOSYS;
+}
+
+static void hv_cpu_hotplug_quirk(bool vmbus_loaded)
+{
+ static void *previous_cpu_disable;
+
+ /*
+ * Offlining a CPU when running on newer hypervisors (WS2012R2, Win8,
+ * ...) is not supported at this moment as channel interrupts are
+ * distributed across all of them.
+ */
+
+ if ((vmbus_proto_version == VERSION_WS2008) ||
+ (vmbus_proto_version == VERSION_WIN7))
+ return;
+
+ if (vmbus_loaded) {
+ previous_cpu_disable = smp_ops.cpu_disable;
+ smp_ops.cpu_disable = hyperv_cpu_disable;
+ pr_notice("CPU offlining is not supported by hypervisor\n");
+ } else if (previous_cpu_disable)
+ smp_ops.cpu_disable = previous_cpu_disable;
+}
+#else
+static void hv_cpu_hotplug_quirk(bool vmbus_loaded)
+{
+}
+#endif
+
+/*
+ * vmbus_bus_init -Main vmbus driver initialization routine.
+ *
+ * Here, we
+ * - initialize the vmbus driver context
+ * - invoke the vmbus hv main init routine
+ * - get the irq resource
+ * - retrieve the channel offers
+ */
+static int vmbus_bus_init(int irq)
+{
+ int ret;
+
+ /* Hypervisor initialization...setup hypercall page..etc */
+ ret = hv_init();
+ if (ret != 0) {
+ pr_err("Unable to initialize the hypervisor - 0x%x\n", ret);
+ return ret;
+ }
+
+ tasklet_init(&msg_dpc, vmbus_on_msg_dpc, 0);
+
+ ret = bus_register(&hv_bus);
+ if (ret)
+ goto err_cleanup;
+
+ hv_setup_vmbus_irq(vmbus_isr);
+
+ ret = hv_synic_alloc();
+ if (ret)
+ goto err_alloc;
+ /*
+ * Initialize the per-cpu interrupt state and
+ * connect to the host.
+ */
+ on_each_cpu(hv_synic_init, NULL, 1);
+ ret = vmbus_connect();
+ if (ret)
+ goto err_alloc;
+
+ hv_cpu_hotplug_quirk(true);
+
+ /*
+ * Only register if the crash MSRs are available
+ */
+ if (ms_hyperv.features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) {
+ atomic_notifier_chain_register(&panic_notifier_list,
+ &hyperv_panic_block);
+ }
+
+ vmbus_request_offers();
+
+ return 0;
+
+err_alloc:
+ hv_synic_free();
+ hv_remove_vmbus_irq();
+
+ bus_unregister(&hv_bus);
+
+err_cleanup:
+ hv_cleanup();
+
+ return ret;
+}
+
+/**
+ * __vmbus_child_driver_register - Register a vmbus's driver
+ * @drv: Pointer to driver structure you want to register
+ * @owner: owner module of the drv
+ * @mod_name: module name string
+ *
+ * Registers the given driver with Linux through the 'driver_register()' call
+ * and sets up the hyper-v vmbus handling for this driver.
+ * It will return the state of the 'driver_register()' call.
+ *
+ */
+int __vmbus_driver_register(struct hv_driver *hv_driver, struct module *owner, const char *mod_name)
+{
+ int ret;
+
+ pr_info("registering driver %s\n", hv_driver->name);
+
+ ret = vmbus_exists();
+ if (ret < 0)
+ return ret;
+
+ hv_driver->driver.name = hv_driver->name;
+ hv_driver->driver.owner = owner;
+ hv_driver->driver.mod_name = mod_name;
+ hv_driver->driver.bus = &hv_bus;
+
+ ret = driver_register(&hv_driver->driver);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(__vmbus_driver_register);
+
+/**
+ * vmbus_driver_unregister() - Unregister a vmbus's driver
+ * @drv: Pointer to driver structure you want to un-register
+ *
+ * Un-register the given driver that was previous registered with a call to
+ * vmbus_driver_register()
+ */
+void vmbus_driver_unregister(struct hv_driver *hv_driver)
+{
+ pr_info("unregistering driver %s\n", hv_driver->name);
+
+ if (!vmbus_exists())
+ driver_unregister(&hv_driver->driver);
+}
+EXPORT_SYMBOL_GPL(vmbus_driver_unregister);
+
+/*
+ * vmbus_device_create - Creates and registers a new child device
+ * on the vmbus.
+ */
+struct hv_device *vmbus_device_create(const uuid_le *type,
+ const uuid_le *instance,
+ struct vmbus_channel *channel)
+{
+ struct hv_device *child_device_obj;
+
+ child_device_obj = kzalloc(sizeof(struct hv_device), GFP_KERNEL);
+ if (!child_device_obj) {
+ pr_err("Unable to allocate device object for child device\n");
+ return NULL;
+ }
+
+ child_device_obj->channel = channel;
+ memcpy(&child_device_obj->dev_type, type, sizeof(uuid_le));
+ memcpy(&child_device_obj->dev_instance, instance,
+ sizeof(uuid_le));
+
+
+ return child_device_obj;
+}
+
+/*
+ * vmbus_device_register - Register the child device
+ */
+int vmbus_device_register(struct hv_device *child_device_obj)
+{
+ int ret = 0;
+
+ dev_set_name(&child_device_obj->device, "vmbus_%d",
+ child_device_obj->channel->id);
+
+ child_device_obj->device.bus = &hv_bus;
+ child_device_obj->device.parent = &hv_acpi_dev->dev;
+ child_device_obj->device.release = vmbus_device_release;
+
+ /*
+ * Register with the LDM. This will kick off the driver/device
+ * binding...which will eventually call vmbus_match() and vmbus_probe()
+ */
+ ret = device_register(&child_device_obj->device);
+
+ if (ret)
+ pr_err("Unable to register child device\n");
+ else
+ pr_debug("child device %s registered\n",
+ dev_name(&child_device_obj->device));
+
+ return ret;
+}
+
+/*
+ * vmbus_device_unregister - Remove the specified child device
+ * from the vmbus.
+ */
+void vmbus_device_unregister(struct hv_device *device_obj)
+{
+ pr_debug("child device %s unregistered\n",
+ dev_name(&device_obj->device));
+
+ /*
+ * Kick off the process of unregistering the device.
+ * This will call vmbus_remove() and eventually vmbus_device_release()
+ */
+ device_unregister(&device_obj->device);
+}
+
+
+/*
+ * VMBUS is an acpi enumerated device. Get the the information we
+ * need from DSDT.
+ */
+
+static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx)
+{
+ switch (res->type) {
+ case ACPI_RESOURCE_TYPE_IRQ:
+ irq = res->data.irq.interrupts[0];
+ break;
+
+ case ACPI_RESOURCE_TYPE_ADDRESS64:
+ hyperv_mmio.start = res->data.address64.address.minimum;
+ hyperv_mmio.end = res->data.address64.address.maximum;
+ break;
+ }
+
+ return AE_OK;
+}
+
+static int vmbus_acpi_add(struct acpi_device *device)
+{
+ acpi_status result;
+ int ret_val = -ENODEV;
+
+ hv_acpi_dev = device;
+
+ result = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
+ vmbus_walk_resources, NULL);
+
+ if (ACPI_FAILURE(result))
+ goto acpi_walk_err;
+ /*
+ * The parent of the vmbus acpi device (Gen2 firmware) is the VMOD that
+ * has the mmio ranges. Get that.
+ */
+ if (device->parent) {
+ result = acpi_walk_resources(device->parent->handle,
+ METHOD_NAME__CRS,
+ vmbus_walk_resources, NULL);
+
+ if (ACPI_FAILURE(result))
+ goto acpi_walk_err;
+ if (hyperv_mmio.start && hyperv_mmio.end)
+ request_resource(&iomem_resource, &hyperv_mmio);
+ }
+ ret_val = 0;
+
+acpi_walk_err:
+ complete(&probe_event);
+ return ret_val;
+}
+
+static const struct acpi_device_id vmbus_acpi_device_ids[] = {
+ {"VMBUS", 0},
+ {"VMBus", 0},
+ {"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, vmbus_acpi_device_ids);
+
+static struct acpi_driver vmbus_acpi_driver = {
+ .name = "vmbus",
+ .ids = vmbus_acpi_device_ids,
+ .ops = {
+ .add = vmbus_acpi_add,
+ },
+};
+
+static int __init hv_acpi_init(void)
+{
+ int ret, t;
+
+ if (x86_hyper != &x86_hyper_ms_hyperv)
+ return -ENODEV;
+
+ init_completion(&probe_event);
+
+ /*
+ * Get irq resources first.
+ */
+ ret = acpi_bus_register_driver(&vmbus_acpi_driver);
+
+ if (ret)
+ return ret;
+
+ t = wait_for_completion_timeout(&probe_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (irq <= 0) {
+ ret = -ENODEV;
+ goto cleanup;
+ }
+
+ ret = vmbus_bus_init(irq);
+ if (ret)
+ goto cleanup;
+
+ return 0;
+
+cleanup:
+ acpi_bus_unregister_driver(&vmbus_acpi_driver);
+ hv_acpi_dev = NULL;
+ return ret;
+}
+
+static void __exit vmbus_exit(void)
+{
+ int cpu;
+
+ vmbus_connection.conn_state = DISCONNECTED;
+ hv_synic_clockevents_cleanup();
+ hv_remove_vmbus_irq();
+ vmbus_free_channels();
+ bus_unregister(&hv_bus);
+ hv_cleanup();
+ for_each_online_cpu(cpu)
+ smp_call_function_single(cpu, hv_synic_cleanup, NULL, 1);
+ acpi_bus_unregister_driver(&vmbus_acpi_driver);
+ hv_cpu_hotplug_quirk(false);
+ vmbus_disconnect();
+}
+
+
+MODULE_LICENSE("GPL");
+
+subsys_initcall(hv_acpi_init);
+module_exit(vmbus_exit);