Linux-libre 4.2-gnu

1 files changed, 2437 insertions, 0 deletions

diff --git a/drivers/staging/unisys/visorbus/visorchipset.c b/drivers/staging/unisys/visorbus/visorchipset.c
new file mode 100644
index 000000000..bb8087e70
--- /dev/null
+++ b/drivers/staging/unisys/visorbus/visorchipset.c
@@ -0,0 +1,2437 @@
+/* visorchipset_main.c
+ *
+ * Copyright (C) 2010 - 2013 UNISYS CORPORATION
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * 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.
+ */
+
+#include <linux/acpi.h>
+#include <linux/cdev.h>
+#include <linux/ctype.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/nls.h>
+#include <linux/netdevice.h>
+#include <linux/platform_device.h>
+#include <linux/uuid.h>
+#include <linux/crash_dump.h>
+
+#include "channel_guid.h"
+#include "controlvmchannel.h"
+#include "controlvmcompletionstatus.h"
+#include "guestlinuxdebug.h"
+#include "periodic_work.h"
+#include "version.h"
+#include "visorbus.h"
+#include "visorbus_private.h"
+#include "vmcallinterface.h"
+
+#define CURRENT_FILE_PC VISOR_CHIPSET_PC_visorchipset_main_c
+
+#define MAX_NAME_SIZE 128
+#define MAX_IP_SIZE   50
+#define MAXOUTSTANDINGCHANNELCOMMAND 256
+#define POLLJIFFIES_CONTROLVMCHANNEL_FAST   1
+#define POLLJIFFIES_CONTROLVMCHANNEL_SLOW 100
+
+#define MAX_CONTROLVM_PAYLOAD_BYTES (1024*128)
+
+#define VISORCHIPSET_MMAP_CONTROLCHANOFFSET	0x00000000
+
+
+#define UNISYS_SPAR_LEAF_ID 0x40000000
+
+/* The s-Par leaf ID returns "UnisysSpar64" encoded across ebx, ecx, edx */
+#define UNISYS_SPAR_ID_EBX 0x73696e55
+#define UNISYS_SPAR_ID_ECX 0x70537379
+#define UNISYS_SPAR_ID_EDX 0x34367261
+
+/*
+ * Module parameters
+ */
+static int visorchipset_major;
+static int visorchipset_visorbusregwait = 1;	/* default is on */
+static int visorchipset_holdchipsetready;
+static unsigned long controlvm_payload_bytes_buffered;
+
+static int
+visorchipset_open(struct inode *inode, struct file *file)
+{
+	unsigned minor_number = iminor(inode);
+
+	if (minor_number)
+		return -ENODEV;
+	file->private_data = NULL;
+	return 0;
+}
+
+static int
+visorchipset_release(struct inode *inode, struct file *file)
+{
+	return 0;
+}
+
+/* When the controlvm channel is idle for at least MIN_IDLE_SECONDS,
+* we switch to slow polling mode.  As soon as we get a controlvm
+* message, we switch back to fast polling mode.
+*/
+#define MIN_IDLE_SECONDS 10
+static unsigned long poll_jiffies = POLLJIFFIES_CONTROLVMCHANNEL_FAST;
+static unsigned long most_recent_message_jiffies;	/* when we got our last
+						 * controlvm message */
+static int visorbusregistered;
+
+#define MAX_CHIPSET_EVENTS 2
+static u8 chipset_events[MAX_CHIPSET_EVENTS] = { 0, 0 };
+
+struct parser_context {
+	unsigned long allocbytes;
+	unsigned long param_bytes;
+	u8 *curr;
+	unsigned long bytes_remaining;
+	bool byte_stream;
+	char data[0];
+};
+
+static struct delayed_work periodic_controlvm_work;
+static struct workqueue_struct *periodic_controlvm_workqueue;
+static DEFINE_SEMAPHORE(notifier_lock);
+
+static struct cdev file_cdev;
+static struct visorchannel **file_controlvm_channel;
+static struct controlvm_message_header g_chipset_msg_hdr;
+static struct controlvm_message_packet g_devicechangestate_packet;
+
+static LIST_HEAD(bus_info_list);
+static LIST_HEAD(dev_info_list);
+
+static struct visorchannel *controlvm_channel;
+
+/* Manages the request payload in the controlvm channel */
+struct visor_controlvm_payload_info {
+	u8 __iomem *ptr;	/* pointer to base address of payload pool */
+	u64 offset;		/* offset from beginning of controlvm
+				 * channel to beginning of payload * pool */
+	u32 bytes;		/* number of bytes in payload pool */
+};
+
+static struct visor_controlvm_payload_info controlvm_payload_info;
+
+/* The following globals are used to handle the scenario where we are unable to
+ * offload the payload from a controlvm message due to memory requirements.  In
+ * this scenario, we simply stash the controlvm message, then attempt to
+ * process it again the next time controlvm_periodic_work() runs.
+ */
+static struct controlvm_message controlvm_pending_msg;
+static bool controlvm_pending_msg_valid;
+
+/* This identifies a data buffer that has been received via a controlvm messages
+ * in a remote --> local CONTROLVM_TRANSMIT_FILE conversation.
+ */
+struct putfile_buffer_entry {
+	struct list_head next;	/* putfile_buffer_entry list */
+	struct parser_context *parser_ctx; /* points to input data buffer */
+};
+
+/* List of struct putfile_request *, via next_putfile_request member.
+ * Each entry in this list identifies an outstanding TRANSMIT_FILE
+ * conversation.
+ */
+static LIST_HEAD(putfile_request_list);
+
+/* This describes a buffer and its current state of transfer (e.g., how many
+ * bytes have already been supplied as putfile data, and how many bytes are
+ * remaining) for a putfile_request.
+ */
+struct putfile_active_buffer {
+	/* a payload from a controlvm message, containing a file data buffer */
+	struct parser_context *parser_ctx;
+	/* points within data area of parser_ctx to next byte of data */
+	u8 *pnext;
+	/* # bytes left from <pnext> to the end of this data buffer */
+	size_t bytes_remaining;
+};
+
+#define PUTFILE_REQUEST_SIG 0x0906101302281211
+/* This identifies a single remote --> local CONTROLVM_TRANSMIT_FILE
+ * conversation.  Structs of this type are dynamically linked into
+ * <Putfile_request_list>.
+ */
+struct putfile_request {
+	u64 sig;		/* PUTFILE_REQUEST_SIG */
+
+	/* header from original TransmitFile request */
+	struct controlvm_message_header controlvm_header;
+	u64 file_request_number;	/* from original TransmitFile request */
+
+	/* link to next struct putfile_request */
+	struct list_head next_putfile_request;
+
+	/* most-recent sequence number supplied via a controlvm message */
+	u64 data_sequence_number;
+
+	/* head of putfile_buffer_entry list, which describes the data to be
+	 * supplied as putfile data;
+	 * - this list is added to when controlvm messages come in that supply
+	 * file data
+	 * - this list is removed from via the hotplug program that is actually
+	 * consuming these buffers to write as file data */
+	struct list_head input_buffer_list;
+	spinlock_t req_list_lock;	/* lock for input_buffer_list */
+
+	/* waiters for input_buffer_list to go non-empty */
+	wait_queue_head_t input_buffer_wq;
+
+	/* data not yet read within current putfile_buffer_entry */
+	struct putfile_active_buffer active_buf;
+
+	/* <0 = failed, 0 = in-progress, >0 = successful; */
+	/* note that this must be set with req_list_lock, and if you set <0, */
+	/* it is your responsibility to also free up all of the other objects */
+	/* in this struct (like input_buffer_list, active_buf.parser_ctx) */
+	/* before releasing the lock */
+	int completion_status;
+};
+
+struct parahotplug_request {
+	struct list_head list;
+	int id;
+	unsigned long expiration;
+	struct controlvm_message msg;
+};
+
+static LIST_HEAD(parahotplug_request_list);
+static DEFINE_SPINLOCK(parahotplug_request_list_lock);	/* lock for above */
+static void parahotplug_process_list(void);
+
+/* Manages the info for a CONTROLVM_DUMP_CAPTURESTATE /
+ * CONTROLVM_REPORTEVENT.
+ */
+static struct visorchipset_busdev_notifiers busdev_notifiers;
+
+static void bus_create_response(struct visor_device *p, int response);
+static void bus_destroy_response(struct visor_device *p, int response);
+static void device_create_response(struct visor_device *p, int response);
+static void device_destroy_response(struct visor_device *p, int response);
+static void device_resume_response(struct visor_device *p, int response);
+
+static void visorchipset_device_pause_response(struct visor_device *p,
+					       int response);
+
+static struct visorchipset_busdev_responders busdev_responders = {
+	.bus_create = bus_create_response,
+	.bus_destroy = bus_destroy_response,
+	.device_create = device_create_response,
+	.device_destroy = device_destroy_response,
+	.device_pause = visorchipset_device_pause_response,
+	.device_resume = device_resume_response,
+};
+
+/* info for /dev/visorchipset */
+static dev_t major_dev = -1; /**< indicates major num for device */
+
+/* prototypes for attributes */
+static ssize_t toolaction_show(struct device *dev,
+			       struct device_attribute *attr, char *buf);
+static ssize_t toolaction_store(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t count);
+static DEVICE_ATTR_RW(toolaction);
+
+static ssize_t boottotool_show(struct device *dev,
+			       struct device_attribute *attr, char *buf);
+static ssize_t boottotool_store(struct device *dev,
+				struct device_attribute *attr, const char *buf,
+				size_t count);
+static DEVICE_ATTR_RW(boottotool);
+
+static ssize_t error_show(struct device *dev, struct device_attribute *attr,
+			  char *buf);
+static ssize_t error_store(struct device *dev, struct device_attribute *attr,
+			   const char *buf, size_t count);
+static DEVICE_ATTR_RW(error);
+
+static ssize_t textid_show(struct device *dev, struct device_attribute *attr,
+			   char *buf);
+static ssize_t textid_store(struct device *dev, struct device_attribute *attr,
+			    const char *buf, size_t count);
+static DEVICE_ATTR_RW(textid);
+
+static ssize_t remaining_steps_show(struct device *dev,
+				    struct device_attribute *attr, char *buf);
+static ssize_t remaining_steps_store(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf, size_t count);
+static DEVICE_ATTR_RW(remaining_steps);
+
+static ssize_t chipsetready_store(struct device *dev,
+				  struct device_attribute *attr,
+				  const char *buf, size_t count);
+static DEVICE_ATTR_WO(chipsetready);
+
+static ssize_t devicedisabled_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count);
+static DEVICE_ATTR_WO(devicedisabled);
+
+static ssize_t deviceenabled_store(struct device *dev,
+				   struct device_attribute *attr,
+				   const char *buf, size_t count);
+static DEVICE_ATTR_WO(deviceenabled);
+
+static struct attribute *visorchipset_install_attrs[] = {
+	&dev_attr_toolaction.attr,
+	&dev_attr_boottotool.attr,
+	&dev_attr_error.attr,
+	&dev_attr_textid.attr,
+	&dev_attr_remaining_steps.attr,
+	NULL
+};
+
+static struct attribute_group visorchipset_install_group = {
+	.name = "install",
+	.attrs = visorchipset_install_attrs
+};
+
+static struct attribute *visorchipset_guest_attrs[] = {
+	&dev_attr_chipsetready.attr,
+	NULL
+};
+
+static struct attribute_group visorchipset_guest_group = {
+	.name = "guest",
+	.attrs = visorchipset_guest_attrs
+};
+
+static struct attribute *visorchipset_parahotplug_attrs[] = {
+	&dev_attr_devicedisabled.attr,
+	&dev_attr_deviceenabled.attr,
+	NULL
+};
+
+static struct attribute_group visorchipset_parahotplug_group = {
+	.name = "parahotplug",
+	.attrs = visorchipset_parahotplug_attrs
+};
+
+static const struct attribute_group *visorchipset_dev_groups[] = {
+	&visorchipset_install_group,
+	&visorchipset_guest_group,
+	&visorchipset_parahotplug_group,
+	NULL
+};
+
+static void visorchipset_dev_release(struct device *dev)
+{
+}
+
+/* /sys/devices/platform/visorchipset */
+static struct platform_device visorchipset_platform_device = {
+	.name = "visorchipset",
+	.id = -1,
+	.dev.groups = visorchipset_dev_groups,
+	.dev.release = visorchipset_dev_release,
+};
+
+/* Function prototypes */
+static void controlvm_respond(struct controlvm_message_header *msg_hdr,
+			      int response);
+static void controlvm_respond_chipset_init(
+		struct controlvm_message_header *msg_hdr, int response,
+		enum ultra_chipset_feature features);
+static void controlvm_respond_physdev_changestate(
+		struct controlvm_message_header *msg_hdr, int response,
+		struct spar_segment_state state);
+
+
+static void parser_done(struct parser_context *ctx);
+
+static struct parser_context *
+parser_init_byte_stream(u64 addr, u32 bytes, bool local, bool *retry)
+{
+	int allocbytes = sizeof(struct parser_context) + bytes;
+	struct parser_context *rc = NULL;
+	struct parser_context *ctx = NULL;
+
+	if (retry)
+		*retry = false;
+
+	/*
+	 * alloc an 0 extra byte to ensure payload is
+	 * '\0'-terminated
+	 */
+	allocbytes++;
+	if ((controlvm_payload_bytes_buffered + bytes)
+	    > MAX_CONTROLVM_PAYLOAD_BYTES) {
+		if (retry)
+			*retry = true;
+		rc = NULL;
+		goto cleanup;
+	}
+	ctx = kzalloc(allocbytes, GFP_KERNEL|__GFP_NORETRY);
+	if (!ctx) {
+		if (retry)
+			*retry = true;
+		rc = NULL;
+		goto cleanup;
+	}
+
+	ctx->allocbytes = allocbytes;
+	ctx->param_bytes = bytes;
+	ctx->curr = NULL;
+	ctx->bytes_remaining = 0;
+	ctx->byte_stream = false;
+	if (local) {
+		void *p;
+
+		if (addr > virt_to_phys(high_memory - 1)) {
+			rc = NULL;
+			goto cleanup;
+		}
+		p = __va((unsigned long) (addr));
+		memcpy(ctx->data, p, bytes);
+	} else {
+		void __iomem *mapping;
+
+		if (!request_mem_region(addr, bytes, "visorchipset")) {
+			rc = NULL;
+			goto cleanup;
+		}
+
+		mapping = ioremap_cache(addr, bytes);
+		if (!mapping) {
+			release_mem_region(addr, bytes);
+			rc = NULL;
+			goto cleanup;
+		}
+		memcpy_fromio(ctx->data, mapping, bytes);
+		release_mem_region(addr, bytes);
+	}
+
+	ctx->byte_stream = true;
+	rc = ctx;
+cleanup:
+	if (rc) {
+		controlvm_payload_bytes_buffered += ctx->param_bytes;
+	} else {
+		if (ctx) {
+			parser_done(ctx);
+			ctx = NULL;
+		}
+	}
+	return rc;
+}
+
+static uuid_le
+parser_id_get(struct parser_context *ctx)
+{
+	struct spar_controlvm_parameters_header *phdr = NULL;
+
+	if (ctx == NULL)
+		return NULL_UUID_LE;
+	phdr = (struct spar_controlvm_parameters_header *)(ctx->data);
+	return phdr->id;
+}
+
+/** Describes the state from the perspective of which controlvm messages have
+ *  been received for a bus or device.
+ */
+
+enum PARSER_WHICH_STRING {
+	PARSERSTRING_INITIATOR,
+	PARSERSTRING_TARGET,
+	PARSERSTRING_CONNECTION,
+	PARSERSTRING_NAME, /* TODO: only PARSERSTRING_NAME is used ? */
+};
+
+static void
+parser_param_start(struct parser_context *ctx,
+		   enum PARSER_WHICH_STRING which_string)
+{
+	struct spar_controlvm_parameters_header *phdr = NULL;
+
+	if (ctx == NULL)
+		goto Away;
+	phdr = (struct spar_controlvm_parameters_header *)(ctx->data);
+	switch (which_string) {
+	case PARSERSTRING_INITIATOR:
+		ctx->curr = ctx->data + phdr->initiator_offset;
+		ctx->bytes_remaining = phdr->initiator_length;
+		break;
+	case PARSERSTRING_TARGET:
+		ctx->curr = ctx->data + phdr->target_offset;
+		ctx->bytes_remaining = phdr->target_length;
+		break;
+	case PARSERSTRING_CONNECTION:
+		ctx->curr = ctx->data + phdr->connection_offset;
+		ctx->bytes_remaining = phdr->connection_length;
+		break;
+	case PARSERSTRING_NAME:
+		ctx->curr = ctx->data + phdr->name_offset;
+		ctx->bytes_remaining = phdr->name_length;
+		break;
+	default:
+		break;
+	}
+
+Away:
+	return;
+}
+
+static void parser_done(struct parser_context *ctx)
+{
+	if (!ctx)
+		return;
+	controlvm_payload_bytes_buffered -= ctx->param_bytes;
+	kfree(ctx);
+}
+
+static void *
+parser_string_get(struct parser_context *ctx)
+{
+	u8 *pscan;
+	unsigned long nscan;
+	int value_length = -1;
+	void *value = NULL;
+	int i;
+
+	if (!ctx)
+		return NULL;
+	pscan = ctx->curr;
+	nscan = ctx->bytes_remaining;
+	if (nscan == 0)
+		return NULL;
+	if (!pscan)
+		return NULL;
+	for (i = 0, value_length = -1; i < nscan; i++)
+		if (pscan[i] == '\0') {
+			value_length = i;
+			break;
+		}
+	if (value_length < 0)	/* '\0' was not included in the length */
+		value_length = nscan;
+	value = kmalloc(value_length + 1, GFP_KERNEL|__GFP_NORETRY);
+	if (value == NULL)
+		return NULL;
+	if (value_length > 0)
+		memcpy(value, pscan, value_length);
+	((u8 *) (value))[value_length] = '\0';
+	return value;
+}
+
+
+static ssize_t toolaction_show(struct device *dev,
+			       struct device_attribute *attr,
+			       char *buf)
+{
+	u8 tool_action;
+
+	visorchannel_read(controlvm_channel,
+		offsetof(struct spar_controlvm_channel_protocol,
+			 tool_action), &tool_action, sizeof(u8));
+	return scnprintf(buf, PAGE_SIZE, "%u\n", tool_action);
+}
+
+static ssize_t toolaction_store(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t count)
+{
+	u8 tool_action;
+	int ret;
+
+	if (kstrtou8(buf, 10, &tool_action))
+		return -EINVAL;
+
+	ret = visorchannel_write(controlvm_channel,
+		offsetof(struct spar_controlvm_channel_protocol,
+			 tool_action),
+		&tool_action, sizeof(u8));
+
+	if (ret)
+		return ret;
+	return count;
+}
+
+static ssize_t boottotool_show(struct device *dev,
+			       struct device_attribute *attr,
+			       char *buf)
+{
+	struct efi_spar_indication efi_spar_indication;
+
+	visorchannel_read(controlvm_channel,
+			  offsetof(struct spar_controlvm_channel_protocol,
+				   efi_spar_ind), &efi_spar_indication,
+			  sizeof(struct efi_spar_indication));
+	return scnprintf(buf, PAGE_SIZE, "%u\n",
+			 efi_spar_indication.boot_to_tool);
+}
+
+static ssize_t boottotool_store(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t count)
+{
+	int val, ret;
+	struct efi_spar_indication efi_spar_indication;
+
+	if (kstrtoint(buf, 10, &val))
+		return -EINVAL;
+
+	efi_spar_indication.boot_to_tool = val;
+	ret = visorchannel_write(controlvm_channel,
+			offsetof(struct spar_controlvm_channel_protocol,
+				 efi_spar_ind), &(efi_spar_indication),
+				 sizeof(struct efi_spar_indication));
+
+	if (ret)
+		return ret;
+	return count;
+}
+
+static ssize_t error_show(struct device *dev, struct device_attribute *attr,
+			  char *buf)
+{
+	u32 error;
+
+	visorchannel_read(controlvm_channel,
+			  offsetof(struct spar_controlvm_channel_protocol,
+				   installation_error),
+			  &error, sizeof(u32));
+	return scnprintf(buf, PAGE_SIZE, "%i\n", error);
+}
+
+static ssize_t error_store(struct device *dev, struct device_attribute *attr,
+			   const char *buf, size_t count)
+{
+	u32 error;
+	int ret;
+
+	if (kstrtou32(buf, 10, &error))
+		return -EINVAL;
+
+	ret = visorchannel_write(controlvm_channel,
+		offsetof(struct spar_controlvm_channel_protocol,
+			 installation_error),
+		&error, sizeof(u32));
+	if (ret)
+		return ret;
+	return count;
+}
+
+static ssize_t textid_show(struct device *dev, struct device_attribute *attr,
+			   char *buf)
+{
+	u32 text_id;
+
+	visorchannel_read(controlvm_channel,
+			  offsetof(struct spar_controlvm_channel_protocol,
+				   installation_text_id),
+			  &text_id, sizeof(u32));
+	return scnprintf(buf, PAGE_SIZE, "%i\n", text_id);
+}
+
+static ssize_t textid_store(struct device *dev, struct device_attribute *attr,
+			    const char *buf, size_t count)
+{
+	u32 text_id;
+	int ret;
+
+	if (kstrtou32(buf, 10, &text_id))
+		return -EINVAL;
+
+	ret = visorchannel_write(controlvm_channel,
+		offsetof(struct spar_controlvm_channel_protocol,
+			 installation_text_id),
+		&text_id, sizeof(u32));
+	if (ret)
+		return ret;
+	return count;
+}
+
+static ssize_t remaining_steps_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	u16 remaining_steps;
+
+	visorchannel_read(controlvm_channel,
+			  offsetof(struct spar_controlvm_channel_protocol,
+				   installation_remaining_steps),
+			  &remaining_steps, sizeof(u16));
+	return scnprintf(buf, PAGE_SIZE, "%hu\n", remaining_steps);
+}
+
+static ssize_t remaining_steps_store(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf, size_t count)
+{
+	u16 remaining_steps;
+	int ret;
+
+	if (kstrtou16(buf, 10, &remaining_steps))
+		return -EINVAL;
+
+	ret = visorchannel_write(controlvm_channel,
+		offsetof(struct spar_controlvm_channel_protocol,
+			 installation_remaining_steps),
+		&remaining_steps, sizeof(u16));
+	if (ret)
+		return ret;
+	return count;
+}
+
+struct visor_busdev {
+	u32 bus_no;
+	u32 dev_no;
+};
+
+static int match_visorbus_dev_by_id(struct device *dev, void *data)
+{
+	struct visor_device *vdev = to_visor_device(dev);
+	struct visor_busdev *id = (struct visor_busdev *)data;
+	u32 bus_no = id->bus_no;
+	u32 dev_no = id->dev_no;
+
+	if ((vdev->chipset_bus_no == bus_no) &&
+	    (vdev->chipset_dev_no == dev_no))
+		return 1;
+
+	return 0;
+}
+struct visor_device *visorbus_get_device_by_id(u32 bus_no, u32 dev_no,
+					       struct visor_device *from)
+{
+	struct device *dev;
+	struct device *dev_start = NULL;
+	struct visor_device *vdev = NULL;
+	struct visor_busdev id = {
+			.bus_no = bus_no,
+			.dev_no = dev_no
+		};
+
+	if (from)
+		dev_start = &from->device;
+	dev = bus_find_device(&visorbus_type, dev_start, (void *)&id,
+			      match_visorbus_dev_by_id);
+	if (dev)
+		vdev = to_visor_device(dev);
+	return vdev;
+}
+EXPORT_SYMBOL(visorbus_get_device_by_id);
+
+static u8
+check_chipset_events(void)
+{
+	int i;
+	u8 send_msg = 1;
+	/* Check events to determine if response should be sent */
+	for (i = 0; i < MAX_CHIPSET_EVENTS; i++)
+		send_msg &= chipset_events[i];
+	return send_msg;
+}
+
+static void
+clear_chipset_events(void)
+{
+	int i;
+	/* Clear chipset_events */
+	for (i = 0; i < MAX_CHIPSET_EVENTS; i++)
+		chipset_events[i] = 0;
+}
+
+void
+visorchipset_register_busdev(
+			struct visorchipset_busdev_notifiers *notifiers,
+			struct visorchipset_busdev_responders *responders,
+			struct ultra_vbus_deviceinfo *driver_info)
+{
+	down(&notifier_lock);
+	if (!notifiers) {
+		memset(&busdev_notifiers, 0,
+		       sizeof(busdev_notifiers));
+		visorbusregistered = 0;	/* clear flag */
+	} else {
+		busdev_notifiers = *notifiers;
+		visorbusregistered = 1;	/* set flag */
+	}
+	if (responders)
+		*responders = busdev_responders;
+	if (driver_info)
+		bus_device_info_init(driver_info, "chipset", "visorchipset",
+				     VERSION, NULL);
+
+	up(&notifier_lock);
+}
+EXPORT_SYMBOL_GPL(visorchipset_register_busdev);
+
+static void
+chipset_init(struct controlvm_message *inmsg)
+{
+	static int chipset_inited;
+	enum ultra_chipset_feature features = 0;
+	int rc = CONTROLVM_RESP_SUCCESS;
+
+	POSTCODE_LINUX_2(CHIPSET_INIT_ENTRY_PC, POSTCODE_SEVERITY_INFO);
+	if (chipset_inited) {
+		rc = -CONTROLVM_RESP_ERROR_ALREADY_DONE;
+		goto cleanup;
+	}
+	chipset_inited = 1;
+	POSTCODE_LINUX_2(CHIPSET_INIT_EXIT_PC, POSTCODE_SEVERITY_INFO);
+
+	/* Set features to indicate we support parahotplug (if Command
+	 * also supports it). */
+	features =
+	    inmsg->cmd.init_chipset.
+	    features & ULTRA_CHIPSET_FEATURE_PARA_HOTPLUG;
+
+	/* Set the "reply" bit so Command knows this is a
+	 * features-aware driver. */
+	features |= ULTRA_CHIPSET_FEATURE_REPLY;
+
+cleanup:
+	if (inmsg->hdr.flags.response_expected)
+		controlvm_respond_chipset_init(&inmsg->hdr, rc, features);
+}
+
+static void
+controlvm_init_response(struct controlvm_message *msg,
+			struct controlvm_message_header *msg_hdr, int response)
+{
+	memset(msg, 0, sizeof(struct controlvm_message));
+	memcpy(&msg->hdr, msg_hdr, sizeof(struct controlvm_message_header));
+	msg->hdr.payload_bytes = 0;
+	msg->hdr.payload_vm_offset = 0;
+	msg->hdr.payload_max_bytes = 0;
+	if (response < 0) {
+		msg->hdr.flags.failed = 1;
+		msg->hdr.completion_status = (u32) (-response);
+	}
+}
+
+static void
+controlvm_respond(struct controlvm_message_header *msg_hdr, int response)
+{
+	struct controlvm_message outmsg;
+
+	controlvm_init_response(&outmsg, msg_hdr, response);
+	if (outmsg.hdr.flags.test_message == 1)
+		return;
+
+	if (!visorchannel_signalinsert(controlvm_channel,
+				       CONTROLVM_QUEUE_REQUEST, &outmsg)) {
+		return;
+	}
+}
+
+static void
+controlvm_respond_chipset_init(struct controlvm_message_header *msg_hdr,
+			       int response,
+			       enum ultra_chipset_feature features)
+{
+	struct controlvm_message outmsg;
+
+	controlvm_init_response(&outmsg, msg_hdr, response);
+	outmsg.cmd.init_chipset.features = features;
+	if (!visorchannel_signalinsert(controlvm_channel,
+				       CONTROLVM_QUEUE_REQUEST, &outmsg)) {
+		return;
+	}
+}
+
+static void controlvm_respond_physdev_changestate(
+		struct controlvm_message_header *msg_hdr, int response,
+		struct spar_segment_state state)
+{
+	struct controlvm_message outmsg;
+
+	controlvm_init_response(&outmsg, msg_hdr, response);
+	outmsg.cmd.device_change_state.state = state;
+	outmsg.cmd.device_change_state.flags.phys_device = 1;
+	if (!visorchannel_signalinsert(controlvm_channel,
+				       CONTROLVM_QUEUE_REQUEST, &outmsg)) {
+		return;
+	}
+}
+
+enum crash_obj_type {
+	CRASH_DEV,
+	CRASH_BUS,
+};
+
+static void
+bus_responder(enum controlvm_id cmd_id,
+	      struct controlvm_message_header *pending_msg_hdr,
+	      int response)
+{
+	if (pending_msg_hdr == NULL)
+		return;		/* no controlvm response needed */
+
+	if (pending_msg_hdr->id != (u32)cmd_id)
+		return;
+
+	controlvm_respond(pending_msg_hdr, response);
+}
+
+static void
+device_changestate_responder(enum controlvm_id cmd_id,
+			     struct visor_device *p, int response,
+			     struct spar_segment_state response_state)
+{
+	struct controlvm_message outmsg;
+	u32 bus_no = p->chipset_bus_no;
+	u32 dev_no = p->chipset_dev_no;
+
+	if (p->pending_msg_hdr == NULL)
+		return;		/* no controlvm response needed */
+	if (p->pending_msg_hdr->id != cmd_id)
+		return;
+
+	controlvm_init_response(&outmsg, p->pending_msg_hdr, response);
+
+	outmsg.cmd.device_change_state.bus_no = bus_no;
+	outmsg.cmd.device_change_state.dev_no = dev_no;
+	outmsg.cmd.device_change_state.state = response_state;
+
+	if (!visorchannel_signalinsert(controlvm_channel,
+				       CONTROLVM_QUEUE_REQUEST, &outmsg))
+		return;
+}
+
+static void
+device_responder(enum controlvm_id cmd_id,
+		 struct controlvm_message_header *pending_msg_hdr,
+		 int response)
+{
+	if (pending_msg_hdr == NULL)
+		return;		/* no controlvm response needed */
+
+	if (pending_msg_hdr->id != (u32)cmd_id)
+		return;
+
+	controlvm_respond(pending_msg_hdr, response);
+}
+
+static void
+bus_epilog(struct visor_device *bus_info,
+	   u32 cmd, struct controlvm_message_header *msg_hdr,
+	   int response, bool need_response)
+{
+	bool notified = false;
+	struct controlvm_message_header *pmsg_hdr = NULL;
+
+	if (!bus_info) {
+		/* relying on a valid passed in response code */
+		/* be lazy and re-use msg_hdr for this failure, is this ok?? */
+		pmsg_hdr = msg_hdr;
+		goto away;
+	}
+
+	if (bus_info->pending_msg_hdr) {
+		/* only non-NULL if dev is still waiting on a response */
+		response = -CONTROLVM_RESP_ERROR_MESSAGE_ID_INVALID_FOR_CLIENT;
+		pmsg_hdr = bus_info->pending_msg_hdr;
+		goto away;
+	}
+
+	if (need_response) {
+		pmsg_hdr = kzalloc(sizeof(*pmsg_hdr), GFP_KERNEL);
+		if (!pmsg_hdr) {
+			response = -CONTROLVM_RESP_ERROR_KMALLOC_FAILED;
+			goto away;
+		}
+
+		memcpy(pmsg_hdr, msg_hdr,
+		       sizeof(struct controlvm_message_header));
+		bus_info->pending_msg_hdr = pmsg_hdr;
+	}
+
+	down(&notifier_lock);
+	if (response == CONTROLVM_RESP_SUCCESS) {
+		switch (cmd) {
+		case CONTROLVM_BUS_CREATE:
+			if (busdev_notifiers.bus_create) {
+				(*busdev_notifiers.bus_create) (bus_info);
+				notified = true;
+			}
+			break;
+		case CONTROLVM_BUS_DESTROY:
+			if (busdev_notifiers.bus_destroy) {
+				(*busdev_notifiers.bus_destroy) (bus_info);
+				notified = true;
+			}
+			break;
+		}
+	}
+away:
+	if (notified)
+		/* The callback function just called above is responsible
+		 * for calling the appropriate visorchipset_busdev_responders
+		 * function, which will call bus_responder()
+		 */
+		;
+	else
+		/*
+		 * Do not kfree(pmsg_hdr) as this is the failure path.
+		 * The success path ('notified') will call the responder
+		 * directly and kfree() there.
+		 */
+		bus_responder(cmd, pmsg_hdr, response);
+	up(&notifier_lock);
+}
+
+static void
+device_epilog(struct visor_device *dev_info,
+	      struct spar_segment_state state, u32 cmd,
+	      struct controlvm_message_header *msg_hdr, int response,
+	      bool need_response, bool for_visorbus)
+{
+	struct visorchipset_busdev_notifiers *notifiers;
+	bool notified = false;
+	struct controlvm_message_header *pmsg_hdr = NULL;
+
+	notifiers = &busdev_notifiers;
+
+	if (!dev_info) {
+		/* relying on a valid passed in response code */
+		/* be lazy and re-use msg_hdr for this failure, is this ok?? */
+		pmsg_hdr = msg_hdr;
+		goto away;
+	}
+
+	if (dev_info->pending_msg_hdr) {
+		/* only non-NULL if dev is still waiting on a response */
+		response = -CONTROLVM_RESP_ERROR_MESSAGE_ID_INVALID_FOR_CLIENT;
+		pmsg_hdr = dev_info->pending_msg_hdr;
+		goto away;
+	}
+
+	if (need_response) {
+		pmsg_hdr = kzalloc(sizeof(*pmsg_hdr), GFP_KERNEL);
+		if (!pmsg_hdr) {
+			response = -CONTROLVM_RESP_ERROR_KMALLOC_FAILED;
+			goto away;
+		}
+
+		memcpy(pmsg_hdr, msg_hdr,
+		       sizeof(struct controlvm_message_header));
+		dev_info->pending_msg_hdr = pmsg_hdr;
+	}
+
+	down(&notifier_lock);
+	if (response >= 0) {
+		switch (cmd) {
+		case CONTROLVM_DEVICE_CREATE:
+			if (notifiers->device_create) {
+				(*notifiers->device_create) (dev_info);
+				notified = true;
+			}
+			break;
+		case CONTROLVM_DEVICE_CHANGESTATE:
+			/* ServerReady / ServerRunning / SegmentStateRunning */
+			if (state.alive == segment_state_running.alive &&
+			    state.operating ==
+				segment_state_running.operating) {
+				if (notifiers->device_resume) {
+					(*notifiers->device_resume) (dev_info);
+					notified = true;
+				}
+			}
+			/* ServerNotReady / ServerLost / SegmentStateStandby */
+			else if (state.alive == segment_state_standby.alive &&
+				 state.operating ==
+				 segment_state_standby.operating) {
+				/* technically this is standby case
+				 * where server is lost
+				 */
+				if (notifiers->device_pause) {
+					(*notifiers->device_pause) (dev_info);
+					notified = true;
+				}
+			}
+			break;
+		case CONTROLVM_DEVICE_DESTROY:
+			if (notifiers->device_destroy) {
+				(*notifiers->device_destroy) (dev_info);
+				notified = true;
+			}
+			break;
+		}
+	}
+away:
+	if (notified)
+		/* The callback function just called above is responsible
+		 * for calling the appropriate visorchipset_busdev_responders
+		 * function, which will call device_responder()
+		 */
+		;
+	else
+		/*
+		 * Do not kfree(pmsg_hdr) as this is the failure path.
+		 * The success path ('notified') will call the responder
+		 * directly and kfree() there.
+		 */
+		device_responder(cmd, pmsg_hdr, response);
+	up(&notifier_lock);
+}
+
+static void
+bus_create(struct controlvm_message *inmsg)
+{
+	struct controlvm_message_packet *cmd = &inmsg->cmd;
+	u32 bus_no = cmd->create_bus.bus_no;
+	int rc = CONTROLVM_RESP_SUCCESS;
+	struct visor_device *bus_info;
+	struct visorchannel *visorchannel;
+
+	bus_info = visorbus_get_device_by_id(bus_no, BUS_ROOT_DEVICE, NULL);
+	if (bus_info && (bus_info->state.created == 1)) {
+		POSTCODE_LINUX_3(BUS_CREATE_FAILURE_PC, bus_no,
+				 POSTCODE_SEVERITY_ERR);
+		rc = -CONTROLVM_RESP_ERROR_ALREADY_DONE;
+		goto cleanup;
+	}
+	bus_info = kzalloc(sizeof(*bus_info), GFP_KERNEL);
+	if (!bus_info) {
+		POSTCODE_LINUX_3(BUS_CREATE_FAILURE_PC, bus_no,
+				 POSTCODE_SEVERITY_ERR);
+		rc = -CONTROLVM_RESP_ERROR_KMALLOC_FAILED;
+		goto cleanup;
+	}
+
+	INIT_LIST_HEAD(&bus_info->list_all);
+	bus_info->chipset_bus_no = bus_no;
+	bus_info->chipset_dev_no = BUS_ROOT_DEVICE;
+
+	POSTCODE_LINUX_3(BUS_CREATE_ENTRY_PC, bus_no, POSTCODE_SEVERITY_INFO);
+
+	visorchannel = visorchannel_create(cmd->create_bus.channel_addr,
+					   cmd->create_bus.channel_bytes,
+					   GFP_KERNEL,
+					   cmd->create_bus.bus_data_type_uuid);
+
+	if (!visorchannel) {
+		POSTCODE_LINUX_3(BUS_CREATE_FAILURE_PC, bus_no,
+				 POSTCODE_SEVERITY_ERR);
+		rc = -CONTROLVM_RESP_ERROR_KMALLOC_FAILED;
+		kfree(bus_info);
+		bus_info = NULL;
+		goto cleanup;
+	}
+	bus_info->visorchannel = visorchannel;
+
+	POSTCODE_LINUX_3(BUS_CREATE_EXIT_PC, bus_no, POSTCODE_SEVERITY_INFO);
+
+cleanup:
+	bus_epilog(bus_info, CONTROLVM_BUS_CREATE, &inmsg->hdr,
+		   rc, inmsg->hdr.flags.response_expected == 1);
+}
+
+static void
+bus_destroy(struct controlvm_message *inmsg)
+{
+	struct controlvm_message_packet *cmd = &inmsg->cmd;
+	u32 bus_no = cmd->destroy_bus.bus_no;
+	struct visor_device *bus_info;
+	int rc = CONTROLVM_RESP_SUCCESS;
+
+	bus_info = visorbus_get_device_by_id(bus_no, BUS_ROOT_DEVICE, NULL);
+	if (!bus_info)
+		rc = -CONTROLVM_RESP_ERROR_BUS_INVALID;
+	else if (bus_info->state.created == 0)
+		rc = -CONTROLVM_RESP_ERROR_ALREADY_DONE;
+
+	bus_epilog(bus_info, CONTROLVM_BUS_DESTROY, &inmsg->hdr,
+		   rc, inmsg->hdr.flags.response_expected == 1);
+
+	/* bus_info is freed as part of the busdevice_release function */
+}
+
+static void
+bus_configure(struct controlvm_message *inmsg,
+	      struct parser_context *parser_ctx)
+{
+	struct controlvm_message_packet *cmd = &inmsg->cmd;
+	u32 bus_no;
+	struct visor_device *bus_info;
+	int rc = CONTROLVM_RESP_SUCCESS;
+
+	bus_no = cmd->configure_bus.bus_no;
+	POSTCODE_LINUX_3(BUS_CONFIGURE_ENTRY_PC, bus_no,
+			 POSTCODE_SEVERITY_INFO);
+
+	bus_info = visorbus_get_device_by_id(bus_no, BUS_ROOT_DEVICE, NULL);
+	if (!bus_info) {
+		POSTCODE_LINUX_3(BUS_CONFIGURE_FAILURE_PC, bus_no,
+				 POSTCODE_SEVERITY_ERR);
+		rc = -CONTROLVM_RESP_ERROR_BUS_INVALID;
+	} else if (bus_info->state.created == 0) {
+		POSTCODE_LINUX_3(BUS_CONFIGURE_FAILURE_PC, bus_no,
+				 POSTCODE_SEVERITY_ERR);
+		rc = -CONTROLVM_RESP_ERROR_BUS_INVALID;
+	} else if (bus_info->pending_msg_hdr != NULL) {
+		POSTCODE_LINUX_3(BUS_CONFIGURE_FAILURE_PC, bus_no,
+				 POSTCODE_SEVERITY_ERR);
+		rc = -CONTROLVM_RESP_ERROR_MESSAGE_ID_INVALID_FOR_CLIENT;
+	} else {
+		visorchannel_set_clientpartition(bus_info->visorchannel,
+				cmd->configure_bus.guest_handle);
+		bus_info->partition_uuid = parser_id_get(parser_ctx);
+		parser_param_start(parser_ctx, PARSERSTRING_NAME);
+		bus_info->name = parser_string_get(parser_ctx);
+
+		POSTCODE_LINUX_3(BUS_CONFIGURE_EXIT_PC, bus_no,
+				 POSTCODE_SEVERITY_INFO);
+	}
+	bus_epilog(bus_info, CONTROLVM_BUS_CONFIGURE, &inmsg->hdr,
+		   rc, inmsg->hdr.flags.response_expected == 1);
+}
+
+static void
+my_device_create(struct controlvm_message *inmsg)
+{
+	struct controlvm_message_packet *cmd = &inmsg->cmd;
+	u32 bus_no = cmd->create_device.bus_no;
+	u32 dev_no = cmd->create_device.dev_no;
+	struct visor_device *dev_info = NULL;
+	struct visor_device *bus_info;
+	struct visorchannel *visorchannel;
+	int rc = CONTROLVM_RESP_SUCCESS;
+
+	bus_info = visorbus_get_device_by_id(bus_no, BUS_ROOT_DEVICE, NULL);
+	if (!bus_info) {
+		POSTCODE_LINUX_4(DEVICE_CREATE_FAILURE_PC, dev_no, bus_no,
+				 POSTCODE_SEVERITY_ERR);
+		rc = -CONTROLVM_RESP_ERROR_BUS_INVALID;
+		goto cleanup;
+	}
+
+	if (bus_info->state.created == 0) {
+		POSTCODE_LINUX_4(DEVICE_CREATE_FAILURE_PC, dev_no, bus_no,
+				 POSTCODE_SEVERITY_ERR);
+		rc = -CONTROLVM_RESP_ERROR_BUS_INVALID;
+		goto cleanup;
+	}
+
+	dev_info = visorbus_get_device_by_id(bus_no, dev_no, NULL);
+	if (dev_info && (dev_info->state.created == 1)) {
+		POSTCODE_LINUX_4(DEVICE_CREATE_FAILURE_PC, dev_no, bus_no,
+				 POSTCODE_SEVERITY_ERR);
+		rc = -CONTROLVM_RESP_ERROR_ALREADY_DONE;
+		goto cleanup;
+	}
+
+	dev_info = kzalloc(sizeof(*dev_info), GFP_KERNEL);
+	if (!dev_info) {
+		POSTCODE_LINUX_4(DEVICE_CREATE_FAILURE_PC, dev_no, bus_no,
+				 POSTCODE_SEVERITY_ERR);
+		rc = -CONTROLVM_RESP_ERROR_KMALLOC_FAILED;
+		goto cleanup;
+	}
+
+	dev_info->chipset_bus_no = bus_no;
+	dev_info->chipset_dev_no = dev_no;
+	dev_info->inst = cmd->create_device.dev_inst_uuid;
+
+	/* not sure where the best place to set the 'parent' */
+	dev_info->device.parent = &bus_info->device;
+
+	POSTCODE_LINUX_4(DEVICE_CREATE_ENTRY_PC, dev_no, bus_no,
+			 POSTCODE_SEVERITY_INFO);
+
+	visorchannel = visorchannel_create(cmd->create_device.channel_addr,
+					   cmd->create_device.channel_bytes,
+					   GFP_KERNEL,
+					   cmd->create_device.data_type_uuid);
+
+	if (!visorchannel) {
+		POSTCODE_LINUX_4(DEVICE_CREATE_FAILURE_PC, dev_no, bus_no,
+				 POSTCODE_SEVERITY_ERR);
+		rc = -CONTROLVM_RESP_ERROR_KMALLOC_FAILED;
+		kfree(dev_info);
+		dev_info = NULL;
+		goto cleanup;
+	}
+	dev_info->visorchannel = visorchannel;
+	dev_info->channel_type_guid = cmd->create_device.data_type_uuid;
+	POSTCODE_LINUX_4(DEVICE_CREATE_EXIT_PC, dev_no, bus_no,
+			 POSTCODE_SEVERITY_INFO);
+cleanup:
+	device_epilog(dev_info, segment_state_running,
+		      CONTROLVM_DEVICE_CREATE, &inmsg->hdr, rc,
+		      inmsg->hdr.flags.response_expected == 1, 1);
+}
+
+static void
+my_device_changestate(struct controlvm_message *inmsg)
+{
+	struct controlvm_message_packet *cmd = &inmsg->cmd;
+	u32 bus_no = cmd->device_change_state.bus_no;
+	u32 dev_no = cmd->device_change_state.dev_no;
+	struct spar_segment_state state = cmd->device_change_state.state;
+	struct visor_device *dev_info;
+	int rc = CONTROLVM_RESP_SUCCESS;
+
+	dev_info = visorbus_get_device_by_id(bus_no, dev_no, NULL);
+	if (!dev_info) {
+		POSTCODE_LINUX_4(DEVICE_CHANGESTATE_FAILURE_PC, dev_no, bus_no,
+				 POSTCODE_SEVERITY_ERR);
+		rc = -CONTROLVM_RESP_ERROR_DEVICE_INVALID;
+	} else if (dev_info->state.created == 0) {
+		POSTCODE_LINUX_4(DEVICE_CHANGESTATE_FAILURE_PC, dev_no, bus_no,
+				 POSTCODE_SEVERITY_ERR);
+		rc = -CONTROLVM_RESP_ERROR_DEVICE_INVALID;
+	}
+	if ((rc >= CONTROLVM_RESP_SUCCESS) && dev_info)
+		device_epilog(dev_info, state,
+			      CONTROLVM_DEVICE_CHANGESTATE, &inmsg->hdr, rc,
+			      inmsg->hdr.flags.response_expected == 1, 1);
+}
+
+static void
+my_device_destroy(struct controlvm_message *inmsg)
+{
+	struct controlvm_message_packet *cmd = &inmsg->cmd;
+	u32 bus_no = cmd->destroy_device.bus_no;
+	u32 dev_no = cmd->destroy_device.dev_no;
+	struct visor_device *dev_info;
+	int rc = CONTROLVM_RESP_SUCCESS;
+
+	dev_info = visorbus_get_device_by_id(bus_no, dev_no, NULL);
+	if (!dev_info)
+		rc = -CONTROLVM_RESP_ERROR_DEVICE_INVALID;
+	else if (dev_info->state.created == 0)
+		rc = -CONTROLVM_RESP_ERROR_ALREADY_DONE;
+
+	if ((rc >= CONTROLVM_RESP_SUCCESS) && dev_info)
+		device_epilog(dev_info, segment_state_running,
+			      CONTROLVM_DEVICE_DESTROY, &inmsg->hdr, rc,
+			      inmsg->hdr.flags.response_expected == 1, 1);
+}
+
+/* When provided with the physical address of the controlvm channel
+ * (phys_addr), the offset to the payload area we need to manage
+ * (offset), and the size of this payload area (bytes), fills in the
+ * controlvm_payload_info struct.  Returns true for success or false
+ * for failure.
+ */
+static int
+initialize_controlvm_payload_info(u64 phys_addr, u64 offset, u32 bytes,
+				  struct visor_controlvm_payload_info *info)
+{
+	u8 __iomem *payload = NULL;
+	int rc = CONTROLVM_RESP_SUCCESS;
+
+	if (!info) {
+		rc = -CONTROLVM_RESP_ERROR_PAYLOAD_INVALID;
+		goto cleanup;
+	}
+	memset(info, 0, sizeof(struct visor_controlvm_payload_info));
+	if ((offset == 0) || (bytes == 0)) {
+		rc = -CONTROLVM_RESP_ERROR_PAYLOAD_INVALID;
+		goto cleanup;
+	}
+	payload = ioremap_cache(phys_addr + offset, bytes);
+	if (!payload) {
+		rc = -CONTROLVM_RESP_ERROR_IOREMAP_FAILED;
+		goto cleanup;
+	}
+
+	info->offset = offset;
+	info->bytes = bytes;
+	info->ptr = payload;
+
+cleanup:
+	if (rc < 0) {
+		if (payload) {
+			iounmap(payload);
+			payload = NULL;
+		}
+	}
+	return rc;
+}
+
+static void
+destroy_controlvm_payload_info(struct visor_controlvm_payload_info *info)
+{
+	if (info->ptr) {
+		iounmap(info->ptr);
+		info->ptr = NULL;
+	}
+	memset(info, 0, sizeof(struct visor_controlvm_payload_info));
+}
+
+static void
+initialize_controlvm_payload(void)
+{
+	u64 phys_addr = visorchannel_get_physaddr(controlvm_channel);
+	u64 payload_offset = 0;
+	u32 payload_bytes = 0;
+
+	if (visorchannel_read(controlvm_channel,
+			      offsetof(struct spar_controlvm_channel_protocol,
+				       request_payload_offset),
+			      &payload_offset, sizeof(payload_offset)) < 0) {
+		POSTCODE_LINUX_2(CONTROLVM_INIT_FAILURE_PC,
+				 POSTCODE_SEVERITY_ERR);
+		return;
+	}
+	if (visorchannel_read(controlvm_channel,
+			      offsetof(struct spar_controlvm_channel_protocol,
+				       request_payload_bytes),
+			      &payload_bytes, sizeof(payload_bytes)) < 0) {
+		POSTCODE_LINUX_2(CONTROLVM_INIT_FAILURE_PC,
+				 POSTCODE_SEVERITY_ERR);
+		return;
+	}
+	initialize_controlvm_payload_info(phys_addr,
+					  payload_offset, payload_bytes,
+					  &controlvm_payload_info);
+}
+
+/*  Send ACTION=online for DEVPATH=/sys/devices/platform/visorchipset.
+ *  Returns CONTROLVM_RESP_xxx code.
+ */
+static int
+visorchipset_chipset_ready(void)
+{
+	kobject_uevent(&visorchipset_platform_device.dev.kobj, KOBJ_ONLINE);
+	return CONTROLVM_RESP_SUCCESS;
+}
+
+static int
+visorchipset_chipset_selftest(void)
+{
+	char env_selftest[20];
+	char *envp[] = { env_selftest, NULL };
+
+	sprintf(env_selftest, "SPARSP_SELFTEST=%d", 1);
+	kobject_uevent_env(&visorchipset_platform_device.dev.kobj, KOBJ_CHANGE,
+			   envp);
+	return CONTROLVM_RESP_SUCCESS;
+}
+
+/*  Send ACTION=offline for DEVPATH=/sys/devices/platform/visorchipset.
+ *  Returns CONTROLVM_RESP_xxx code.
+ */
+static int
+visorchipset_chipset_notready(void)
+{
+	kobject_uevent(&visorchipset_platform_device.dev.kobj, KOBJ_OFFLINE);
+	return CONTROLVM_RESP_SUCCESS;
+}
+
+static void
+chipset_ready(struct controlvm_message_header *msg_hdr)
+{
+	int rc = visorchipset_chipset_ready();
+
+	if (rc != CONTROLVM_RESP_SUCCESS)
+		rc = -rc;
+	if (msg_hdr->flags.response_expected && !visorchipset_holdchipsetready)
+		controlvm_respond(msg_hdr, rc);
+	if (msg_hdr->flags.response_expected && visorchipset_holdchipsetready) {
+		/* Send CHIPSET_READY response when all modules have been loaded
+		 * and disks mounted for the partition
+		 */
+		g_chipset_msg_hdr = *msg_hdr;
+	}
+}
+
+static void
+chipset_selftest(struct controlvm_message_header *msg_hdr)
+{
+	int rc = visorchipset_chipset_selftest();
+
+	if (rc != CONTROLVM_RESP_SUCCESS)
+		rc = -rc;
+	if (msg_hdr->flags.response_expected)
+		controlvm_respond(msg_hdr, rc);
+}
+
+static void
+chipset_notready(struct controlvm_message_header *msg_hdr)
+{
+	int rc = visorchipset_chipset_notready();
+
+	if (rc != CONTROLVM_RESP_SUCCESS)
+		rc = -rc;
+	if (msg_hdr->flags.response_expected)
+		controlvm_respond(msg_hdr, rc);
+}
+
+/* This is your "one-stop" shop for grabbing the next message from the
+ * CONTROLVM_QUEUE_EVENT queue in the controlvm channel.
+ */
+static bool
+read_controlvm_event(struct controlvm_message *msg)
+{
+	if (visorchannel_signalremove(controlvm_channel,
+				      CONTROLVM_QUEUE_EVENT, msg)) {
+		/* got a message */
+		if (msg->hdr.flags.test_message == 1)
+			return false;
+		return true;
+	}
+	return false;
+}
+
+/*
+ * The general parahotplug flow works as follows.  The visorchipset
+ * driver receives a DEVICE_CHANGESTATE message from Command
+ * specifying a physical device to enable or disable.  The CONTROLVM
+ * message handler calls parahotplug_process_message, which then adds
+ * the message to a global list and kicks off a udev event which
+ * causes a user level script to enable or disable the specified
+ * device.  The udev script then writes to
+ * /proc/visorchipset/parahotplug, which causes parahotplug_proc_write
+ * to get called, at which point the appropriate CONTROLVM message is
+ * retrieved from the list and responded to.
+ */
+
+#define PARAHOTPLUG_TIMEOUT_MS 2000
+
+/*
+ * Generate unique int to match an outstanding CONTROLVM message with a
+ * udev script /proc response
+ */
+static int
+parahotplug_next_id(void)
+{
+	static atomic_t id = ATOMIC_INIT(0);
+
+	return atomic_inc_return(&id);
+}
+
+/*
+ * Returns the time (in jiffies) when a CONTROLVM message on the list
+ * should expire -- PARAHOTPLUG_TIMEOUT_MS in the future
+ */
+static unsigned long
+parahotplug_next_expiration(void)
+{
+	return jiffies + msecs_to_jiffies(PARAHOTPLUG_TIMEOUT_MS);
+}
+
+/*
+ * Create a parahotplug_request, which is basically a wrapper for a
+ * CONTROLVM_MESSAGE that we can stick on a list
+ */
+static struct parahotplug_request *
+parahotplug_request_create(struct controlvm_message *msg)
+{
+	struct parahotplug_request *req;
+
+	req = kmalloc(sizeof(*req), GFP_KERNEL | __GFP_NORETRY);
+	if (!req)
+		return NULL;
+
+	req->id = parahotplug_next_id();
+	req->expiration = parahotplug_next_expiration();
+	req->msg = *msg;
+
+	return req;
+}
+
+/*
+ * Free a parahotplug_request.
+ */
+static void
+parahotplug_request_destroy(struct parahotplug_request *req)
+{
+	kfree(req);
+}
+
+/*
+ * Cause uevent to run the user level script to do the disable/enable
+ * specified in (the CONTROLVM message in) the specified
+ * parahotplug_request
+ */
+static void
+parahotplug_request_kickoff(struct parahotplug_request *req)
+{
+	struct controlvm_message_packet *cmd = &req->msg.cmd;
+	char env_cmd[40], env_id[40], env_state[40], env_bus[40], env_dev[40],
+	    env_func[40];
+	char *envp[] = {
+		env_cmd, env_id, env_state, env_bus, env_dev, env_func, NULL
+	};
+
+	sprintf(env_cmd, "SPAR_PARAHOTPLUG=1");
+	sprintf(env_id, "SPAR_PARAHOTPLUG_ID=%d", req->id);
+	sprintf(env_state, "SPAR_PARAHOTPLUG_STATE=%d",
+		cmd->device_change_state.state.active);
+	sprintf(env_bus, "SPAR_PARAHOTPLUG_BUS=%d",
+		cmd->device_change_state.bus_no);
+	sprintf(env_dev, "SPAR_PARAHOTPLUG_DEVICE=%d",
+		cmd->device_change_state.dev_no >> 3);
+	sprintf(env_func, "SPAR_PARAHOTPLUG_FUNCTION=%d",
+		cmd->device_change_state.dev_no & 0x7);
+
+	kobject_uevent_env(&visorchipset_platform_device.dev.kobj, KOBJ_CHANGE,
+			   envp);
+}
+
+/*
+ * Remove any request from the list that's been on there too long and
+ * respond with an error.
+ */
+static void
+parahotplug_process_list(void)
+{
+	struct list_head *pos;
+	struct list_head *tmp;
+
+	spin_lock(&parahotplug_request_list_lock);
+
+	list_for_each_safe(pos, tmp, &parahotplug_request_list) {
+		struct parahotplug_request *req =
+		    list_entry(pos, struct parahotplug_request, list);
+
+		if (!time_after_eq(jiffies, req->expiration))
+			continue;
+
+		list_del(pos);
+		if (req->msg.hdr.flags.response_expected)
+			controlvm_respond_physdev_changestate(
+				&req->msg.hdr,
+				CONTROLVM_RESP_ERROR_DEVICE_UDEV_TIMEOUT,
+				req->msg.cmd.device_change_state.state);
+		parahotplug_request_destroy(req);
+	}
+
+	spin_unlock(&parahotplug_request_list_lock);
+}
+
+/*
+ * Called from the /proc handler, which means the user script has
+ * finished the enable/disable.  Find the matching identifier, and
+ * respond to the CONTROLVM message with success.
+ */
+static int
+parahotplug_request_complete(int id, u16 active)
+{
+	struct list_head *pos;
+	struct list_head *tmp;
+
+	spin_lock(&parahotplug_request_list_lock);
+
+	/* Look for a request matching "id". */
+	list_for_each_safe(pos, tmp, &parahotplug_request_list) {
+		struct parahotplug_request *req =
+		    list_entry(pos, struct parahotplug_request, list);
+		if (req->id == id) {
+			/* Found a match.  Remove it from the list and
+			 * respond.
+			 */
+			list_del(pos);
+			spin_unlock(&parahotplug_request_list_lock);
+			req->msg.cmd.device_change_state.state.active = active;
+			if (req->msg.hdr.flags.response_expected)
+				controlvm_respond_physdev_changestate(
+					&req->msg.hdr, CONTROLVM_RESP_SUCCESS,
+					req->msg.cmd.device_change_state.state);
+			parahotplug_request_destroy(req);
+			return 0;
+		}
+	}
+
+	spin_unlock(&parahotplug_request_list_lock);
+	return -1;
+}
+
+/*
+ * Enables or disables a PCI device by kicking off a udev script
+ */
+static void
+parahotplug_process_message(struct controlvm_message *inmsg)
+{
+	struct parahotplug_request *req;
+
+	req = parahotplug_request_create(inmsg);
+
+	if (!req)
+		return;
+
+	if (inmsg->cmd.device_change_state.state.active) {
+		/* For enable messages, just respond with success
+		* right away.  This is a bit of a hack, but there are
+		* issues with the early enable messages we get (with
+		* either the udev script not detecting that the device
+		* is up, or not getting called at all).  Fortunately
+		* the messages that get lost don't matter anyway, as
+		* devices are automatically enabled at
+		* initialization.
+		*/
+		parahotplug_request_kickoff(req);
+		controlvm_respond_physdev_changestate(&inmsg->hdr,
+			CONTROLVM_RESP_SUCCESS,
+			inmsg->cmd.device_change_state.state);
+		parahotplug_request_destroy(req);
+	} else {
+		/* For disable messages, add the request to the
+		* request list before kicking off the udev script.  It
+		* won't get responded to until the script has
+		* indicated it's done.
+		*/
+		spin_lock(&parahotplug_request_list_lock);
+		list_add_tail(&req->list, &parahotplug_request_list);
+		spin_unlock(&parahotplug_request_list_lock);
+
+		parahotplug_request_kickoff(req);
+	}
+}
+
+/* Process a controlvm message.
+ * Return result:
+ *    false - this function will return false only in the case where the
+ *            controlvm message was NOT processed, but processing must be
+ *            retried before reading the next controlvm message; a
+ *            scenario where this can occur is when we need to throttle
+ *            the allocation of memory in which to copy out controlvm
+ *            payload data
+ *    true  - processing of the controlvm message completed,
+ *            either successfully or with an error.
+ */
+static bool
+handle_command(struct controlvm_message inmsg, u64 channel_addr)
+{
+	struct controlvm_message_packet *cmd = &inmsg.cmd;
+	u64 parm_addr;
+	u32 parm_bytes;
+	struct parser_context *parser_ctx = NULL;
+	bool local_addr;
+	struct controlvm_message ackmsg;
+
+	/* create parsing context if necessary */
+	local_addr = (inmsg.hdr.flags.test_message == 1);
+	if (channel_addr == 0)
+		return true;
+	parm_addr = channel_addr + inmsg.hdr.payload_vm_offset;
+	parm_bytes = inmsg.hdr.payload_bytes;
+
+	/* Parameter and channel addresses within test messages actually lie
+	 * within our OS-controlled memory.  We need to know that, because it
+	 * makes a difference in how we compute the virtual address.
+	 */
+	if (parm_addr && parm_bytes) {
+		bool retry = false;
+
+		parser_ctx =
+		    parser_init_byte_stream(parm_addr, parm_bytes,
+					    local_addr, &retry);
+		if (!parser_ctx && retry)
+			return false;
+	}
+
+	if (!local_addr) {
+		controlvm_init_response(&ackmsg, &inmsg.hdr,
+					CONTROLVM_RESP_SUCCESS);
+		if (controlvm_channel)
+			visorchannel_signalinsert(controlvm_channel,
+						  CONTROLVM_QUEUE_ACK,
+						  &ackmsg);
+	}
+	switch (inmsg.hdr.id) {
+	case CONTROLVM_CHIPSET_INIT:
+		chipset_init(&inmsg);
+		break;
+	case CONTROLVM_BUS_CREATE:
+		bus_create(&inmsg);
+		break;
+	case CONTROLVM_BUS_DESTROY:
+		bus_destroy(&inmsg);
+		break;
+	case CONTROLVM_BUS_CONFIGURE:
+		bus_configure(&inmsg, parser_ctx);
+		break;
+	case CONTROLVM_DEVICE_CREATE:
+		my_device_create(&inmsg);
+		break;
+	case CONTROLVM_DEVICE_CHANGESTATE:
+		if (cmd->device_change_state.flags.phys_device) {
+			parahotplug_process_message(&inmsg);
+		} else {
+			/* save the hdr and cmd structures for later use */
+			/* when sending back the response to Command */
+			my_device_changestate(&inmsg);
+			g_devicechangestate_packet = inmsg.cmd;
+			break;
+		}
+		break;
+	case CONTROLVM_DEVICE_DESTROY:
+		my_device_destroy(&inmsg);
+		break;
+	case CONTROLVM_DEVICE_CONFIGURE:
+		/* no op for now, just send a respond that we passed */
+		if (inmsg.hdr.flags.response_expected)
+			controlvm_respond(&inmsg.hdr, CONTROLVM_RESP_SUCCESS);
+		break;
+	case CONTROLVM_CHIPSET_READY:
+		chipset_ready(&inmsg.hdr);
+		break;
+	case CONTROLVM_CHIPSET_SELFTEST:
+		chipset_selftest(&inmsg.hdr);
+		break;
+	case CONTROLVM_CHIPSET_STOP:
+		chipset_notready(&inmsg.hdr);
+		break;
+	default:
+		if (inmsg.hdr.flags.response_expected)
+			controlvm_respond(&inmsg.hdr,
+				-CONTROLVM_RESP_ERROR_MESSAGE_ID_UNKNOWN);
+		break;
+	}
+
+	if (parser_ctx) {
+		parser_done(parser_ctx);
+		parser_ctx = NULL;
+	}
+	return true;
+}
+
+static inline unsigned int
+issue_vmcall_io_controlvm_addr(u64 *control_addr, u32 *control_bytes)
+{
+	struct vmcall_io_controlvm_addr_params params;
+	int result = VMCALL_SUCCESS;
+	u64 physaddr;
+
+	physaddr = virt_to_phys(&params);
+	ISSUE_IO_VMCALL(VMCALL_IO_CONTROLVM_ADDR, physaddr, result);
+	if (VMCALL_SUCCESSFUL(result)) {
+		*control_addr = params.address;
+		*control_bytes = params.channel_bytes;
+	}
+	return result;
+}
+
+static u64 controlvm_get_channel_address(void)
+{
+	u64 addr = 0;
+	u32 size = 0;
+
+	if (!VMCALL_SUCCESSFUL(issue_vmcall_io_controlvm_addr(&addr, &size)))
+		return 0;
+
+	return addr;
+}
+
+static void
+controlvm_periodic_work(struct work_struct *work)
+{
+	struct controlvm_message inmsg;
+	bool got_command = false;
+	bool handle_command_failed = false;
+	static u64 poll_count;
+
+	/* make sure visorbus server is registered for controlvm callbacks */
+	if (visorchipset_visorbusregwait && !visorbusregistered)
+		goto cleanup;
+
+	poll_count++;
+	if (poll_count >= 250)
+		;	/* keep going */
+	else
+		goto cleanup;
+
+	/* Check events to determine if response to CHIPSET_READY
+	 * should be sent
+	 */
+	if (visorchipset_holdchipsetready &&
+	    (g_chipset_msg_hdr.id != CONTROLVM_INVALID)) {
+		if (check_chipset_events() == 1) {
+			controlvm_respond(&g_chipset_msg_hdr, 0);
+			clear_chipset_events();
+			memset(&g_chipset_msg_hdr, 0,
+			       sizeof(struct controlvm_message_header));
+		}
+	}
+
+	while (visorchannel_signalremove(controlvm_channel,
+					 CONTROLVM_QUEUE_RESPONSE,
+					 &inmsg))
+		;
+	if (!got_command) {
+		if (controlvm_pending_msg_valid) {
+			/* we throttled processing of a prior
+			* msg, so try to process it again
+			* rather than reading a new one
+			*/
+			inmsg = controlvm_pending_msg;
+			controlvm_pending_msg_valid = false;
+			got_command = true;
+		} else {
+			got_command = read_controlvm_event(&inmsg);
+		}
+	}
+
+	handle_command_failed = false;
+	while (got_command && (!handle_command_failed)) {
+		most_recent_message_jiffies = jiffies;
+		if (handle_command(inmsg,
+				   visorchannel_get_physaddr
+				   (controlvm_channel)))
+			got_command = read_controlvm_event(&inmsg);
+		else {
+			/* this is a scenario where throttling
+			* is required, but probably NOT an
+			* error...; we stash the current
+			* controlvm msg so we will attempt to
+			* reprocess it on our next loop
+			*/
+			handle_command_failed = true;
+			controlvm_pending_msg = inmsg;
+			controlvm_pending_msg_valid = true;
+		}
+	}
+
+	/* parahotplug_worker */
+	parahotplug_process_list();
+
+cleanup:
+
+	if (time_after(jiffies,
+		       most_recent_message_jiffies + (HZ * MIN_IDLE_SECONDS))) {
+		/* it's been longer than MIN_IDLE_SECONDS since we
+		* processed our last controlvm message; slow down the
+		* polling
+		*/
+		if (poll_jiffies != POLLJIFFIES_CONTROLVMCHANNEL_SLOW)
+			poll_jiffies = POLLJIFFIES_CONTROLVMCHANNEL_SLOW;
+	} else {
+		if (poll_jiffies != POLLJIFFIES_CONTROLVMCHANNEL_FAST)
+			poll_jiffies = POLLJIFFIES_CONTROLVMCHANNEL_FAST;
+	}
+
+	queue_delayed_work(periodic_controlvm_workqueue,
+			   &periodic_controlvm_work, poll_jiffies);
+}
+
+static void
+setup_crash_devices_work_queue(struct work_struct *work)
+{
+	struct controlvm_message local_crash_bus_msg;
+	struct controlvm_message local_crash_dev_msg;
+	struct controlvm_message msg;
+	u32 local_crash_msg_offset;
+	u16 local_crash_msg_count;
+
+	/* make sure visorbus is registered for controlvm callbacks */
+	if (visorchipset_visorbusregwait && !visorbusregistered)
+		goto cleanup;
+
+	POSTCODE_LINUX_2(CRASH_DEV_ENTRY_PC, POSTCODE_SEVERITY_INFO);
+
+	/* send init chipset msg */
+	msg.hdr.id = CONTROLVM_CHIPSET_INIT;
+	msg.cmd.init_chipset.bus_count = 23;
+	msg.cmd.init_chipset.switch_count = 0;
+
+	chipset_init(&msg);
+
+	/* get saved message count */
+	if (visorchannel_read(controlvm_channel,
+			      offsetof(struct spar_controlvm_channel_protocol,
+				       saved_crash_message_count),
+			      &local_crash_msg_count, sizeof(u16)) < 0) {
+		POSTCODE_LINUX_2(CRASH_DEV_CTRL_RD_FAILURE_PC,
+				 POSTCODE_SEVERITY_ERR);
+		return;
+	}
+
+	if (local_crash_msg_count != CONTROLVM_CRASHMSG_MAX) {
+		POSTCODE_LINUX_3(CRASH_DEV_COUNT_FAILURE_PC,
+				 local_crash_msg_count,
+				 POSTCODE_SEVERITY_ERR);
+		return;
+	}
+
+	/* get saved crash message offset */
+	if (visorchannel_read(controlvm_channel,
+			      offsetof(struct spar_controlvm_channel_protocol,
+				       saved_crash_message_offset),
+			      &local_crash_msg_offset, sizeof(u32)) < 0) {
+		POSTCODE_LINUX_2(CRASH_DEV_CTRL_RD_FAILURE_PC,
+				 POSTCODE_SEVERITY_ERR);
+		return;
+	}
+
+	/* read create device message for storage bus offset */
+	if (visorchannel_read(controlvm_channel,
+			      local_crash_msg_offset,
+			      &local_crash_bus_msg,
+			      sizeof(struct controlvm_message)) < 0) {
+		POSTCODE_LINUX_2(CRASH_DEV_RD_BUS_FAIULRE_PC,
+				 POSTCODE_SEVERITY_ERR);
+		return;
+	}
+
+	/* read create device message for storage device */
+	if (visorchannel_read(controlvm_channel,
+			      local_crash_msg_offset +
+			      sizeof(struct controlvm_message),
+			      &local_crash_dev_msg,
+			      sizeof(struct controlvm_message)) < 0) {
+		POSTCODE_LINUX_2(CRASH_DEV_RD_DEV_FAIULRE_PC,
+				 POSTCODE_SEVERITY_ERR);
+		return;
+	}
+
+	/* reuse IOVM create bus message */
+	if (local_crash_bus_msg.cmd.create_bus.channel_addr) {
+		bus_create(&local_crash_bus_msg);
+	} else {
+		POSTCODE_LINUX_2(CRASH_DEV_BUS_NULL_FAILURE_PC,
+				 POSTCODE_SEVERITY_ERR);
+		return;
+	}
+
+	/* reuse create device message for storage device */
+	if (local_crash_dev_msg.cmd.create_device.channel_addr) {
+		my_device_create(&local_crash_dev_msg);
+	} else {
+		POSTCODE_LINUX_2(CRASH_DEV_DEV_NULL_FAILURE_PC,
+				 POSTCODE_SEVERITY_ERR);
+		return;
+	}
+	POSTCODE_LINUX_2(CRASH_DEV_EXIT_PC, POSTCODE_SEVERITY_INFO);
+	return;
+
+cleanup:
+
+	poll_jiffies = POLLJIFFIES_CONTROLVMCHANNEL_SLOW;
+
+	queue_delayed_work(periodic_controlvm_workqueue,
+			   &periodic_controlvm_work, poll_jiffies);
+}
+
+static void
+bus_create_response(struct visor_device *bus_info, int response)
+{
+	if (response >= 0)
+		bus_info->state.created = 1;
+
+	bus_responder(CONTROLVM_BUS_CREATE, bus_info->pending_msg_hdr,
+		      response);
+
+	kfree(bus_info->pending_msg_hdr);
+	bus_info->pending_msg_hdr = NULL;
+}
+
+static void
+bus_destroy_response(struct visor_device *bus_info, int response)
+{
+	bus_responder(CONTROLVM_BUS_DESTROY, bus_info->pending_msg_hdr,
+		      response);
+
+	kfree(bus_info->pending_msg_hdr);
+	bus_info->pending_msg_hdr = NULL;
+}
+
+static void
+device_create_response(struct visor_device *dev_info, int response)
+{
+	if (response >= 0)
+		dev_info->state.created = 1;
+
+	device_responder(CONTROLVM_DEVICE_CREATE, dev_info->pending_msg_hdr,
+			 response);
+
+	kfree(dev_info->pending_msg_hdr);
+}
+
+static void
+device_destroy_response(struct visor_device *dev_info, int response)
+{
+	device_responder(CONTROLVM_DEVICE_DESTROY, dev_info->pending_msg_hdr,
+			 response);
+
+	kfree(dev_info->pending_msg_hdr);
+	dev_info->pending_msg_hdr = NULL;
+}
+
+static void
+visorchipset_device_pause_response(struct visor_device *dev_info,
+				   int response)
+{
+	device_changestate_responder(CONTROLVM_DEVICE_CHANGESTATE,
+				     dev_info, response,
+				     segment_state_standby);
+
+	kfree(dev_info->pending_msg_hdr);
+	dev_info->pending_msg_hdr = NULL;
+}
+
+static void
+device_resume_response(struct visor_device *dev_info, int response)
+{
+	device_changestate_responder(CONTROLVM_DEVICE_CHANGESTATE,
+				     dev_info, response,
+				     segment_state_running);
+
+	kfree(dev_info->pending_msg_hdr);
+	dev_info->pending_msg_hdr = NULL;
+}
+
+static ssize_t chipsetready_store(struct device *dev,
+				  struct device_attribute *attr,
+				  const char *buf, size_t count)
+{
+	char msgtype[64];
+
+	if (sscanf(buf, "%63s", msgtype) != 1)
+		return -EINVAL;
+
+	if (!strcmp(msgtype, "CALLHOMEDISK_MOUNTED")) {
+		chipset_events[0] = 1;
+		return count;
+	} else if (!strcmp(msgtype, "MODULES_LOADED")) {
+		chipset_events[1] = 1;
+		return count;
+	}
+	return -EINVAL;
+}
+
+/* The parahotplug/devicedisabled interface gets called by our support script
+ * when an SR-IOV device has been shut down. The ID is passed to the script
+ * and then passed back when the device has been removed.
+ */
+static ssize_t devicedisabled_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+	unsigned int id;
+
+	if (kstrtouint(buf, 10, &id))
+		return -EINVAL;
+
+	parahotplug_request_complete(id, 0);
+	return count;
+}
+
+/* The parahotplug/deviceenabled interface gets called by our support script
+ * when an SR-IOV device has been recovered. The ID is passed to the script
+ * and then passed back when the device has been brought back up.
+ */
+static ssize_t deviceenabled_store(struct device *dev,
+				   struct device_attribute *attr,
+				   const char *buf, size_t count)
+{
+	unsigned int id;
+
+	if (kstrtouint(buf, 10, &id))
+		return -EINVAL;
+
+	parahotplug_request_complete(id, 1);
+	return count;
+}
+
+static int
+visorchipset_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	unsigned long physaddr = 0;
+	unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
+	u64 addr = 0;
+
+	/* sv_enable_dfp(); */
+	if (offset & (PAGE_SIZE - 1))
+		return -ENXIO;	/* need aligned offsets */
+
+	switch (offset) {
+	case VISORCHIPSET_MMAP_CONTROLCHANOFFSET:
+		vma->vm_flags |= VM_IO;
+		if (!*file_controlvm_channel)
+			return -ENXIO;
+
+		visorchannel_read(*file_controlvm_channel,
+			offsetof(struct spar_controlvm_channel_protocol,
+				 gp_control_channel),
+			&addr, sizeof(addr));
+		if (!addr)
+			return -ENXIO;
+
+		physaddr = (unsigned long)addr;
+		if (remap_pfn_range(vma, vma->vm_start,
+				    physaddr >> PAGE_SHIFT,
+				    vma->vm_end - vma->vm_start,
+				    /*pgprot_noncached */
+				    (vma->vm_page_prot))) {
+			return -EAGAIN;
+		}
+		break;
+	default:
+		return -ENXIO;
+	}
+	return 0;
+}
+
+static inline s64 issue_vmcall_query_guest_virtual_time_offset(void)
+{
+	u64 result = VMCALL_SUCCESS;
+	u64 physaddr = 0;
+
+	ISSUE_IO_VMCALL(VMCALL_QUERY_GUEST_VIRTUAL_TIME_OFFSET, physaddr,
+			result);
+	return result;
+}
+
+static inline int issue_vmcall_update_physical_time(u64 adjustment)
+{
+	int result = VMCALL_SUCCESS;
+
+	ISSUE_IO_VMCALL(VMCALL_UPDATE_PHYSICAL_TIME, adjustment, result);
+	return result;
+}
+
+static long visorchipset_ioctl(struct file *file, unsigned int cmd,
+			       unsigned long arg)
+{
+	s64 adjustment;
+	s64 vrtc_offset;
+
+	switch (cmd) {
+	case VMCALL_QUERY_GUEST_VIRTUAL_TIME_OFFSET:
+		/* get the physical rtc offset */
+		vrtc_offset = issue_vmcall_query_guest_virtual_time_offset();
+		if (copy_to_user((void __user *)arg, &vrtc_offset,
+				 sizeof(vrtc_offset))) {
+			return -EFAULT;
+		}
+		return 0;
+	case VMCALL_UPDATE_PHYSICAL_TIME:
+		if (copy_from_user(&adjustment, (void __user *)arg,
+				   sizeof(adjustment))) {
+			return -EFAULT;
+		}
+		return issue_vmcall_update_physical_time(adjustment);
+	default:
+		return -EFAULT;
+	}
+}
+
+static const struct file_operations visorchipset_fops = {
+	.owner = THIS_MODULE,
+	.open = visorchipset_open,
+	.read = NULL,
+	.write = NULL,
+	.unlocked_ioctl = visorchipset_ioctl,
+	.release = visorchipset_release,
+	.mmap = visorchipset_mmap,
+};
+
+static int
+visorchipset_file_init(dev_t major_dev, struct visorchannel **controlvm_channel)
+{
+	int rc = 0;
+
+	file_controlvm_channel = controlvm_channel;
+	cdev_init(&file_cdev, &visorchipset_fops);
+	file_cdev.owner = THIS_MODULE;
+	if (MAJOR(major_dev) == 0) {
+		rc = alloc_chrdev_region(&major_dev, 0, 1, "visorchipset");
+		/* dynamic major device number registration required */
+		if (rc < 0)
+			return rc;
+	} else {
+		/* static major device number registration required */
+		rc = register_chrdev_region(major_dev, 1, "visorchipset");
+		if (rc < 0)
+			return rc;
+	}
+	rc = cdev_add(&file_cdev, MKDEV(MAJOR(major_dev), 0), 1);
+	if (rc < 0) {
+		unregister_chrdev_region(major_dev, 1);
+		return rc;
+	}
+	return 0;
+}
+
+static int
+visorchipset_init(struct acpi_device *acpi_device)
+{
+	int rc = 0;
+	u64 addr;
+	int tmp_sz = sizeof(struct spar_controlvm_channel_protocol);
+	uuid_le uuid = SPAR_CONTROLVM_CHANNEL_PROTOCOL_UUID;
+
+	addr = controlvm_get_channel_address();
+	if (!addr)
+		return -ENODEV;
+
+	memset(&busdev_notifiers, 0, sizeof(busdev_notifiers));
+	memset(&controlvm_payload_info, 0, sizeof(controlvm_payload_info));
+
+	controlvm_channel = visorchannel_create_with_lock(addr, tmp_sz,
+							  GFP_KERNEL, uuid);
+	if (SPAR_CONTROLVM_CHANNEL_OK_CLIENT(
+		    visorchannel_get_header(controlvm_channel))) {
+		initialize_controlvm_payload();
+	} else {
+		visorchannel_destroy(controlvm_channel);
+		controlvm_channel = NULL;
+		return -ENODEV;
+	}
+
+	major_dev = MKDEV(visorchipset_major, 0);
+	rc = visorchipset_file_init(major_dev, &controlvm_channel);
+	if (rc < 0) {
+		POSTCODE_LINUX_2(CHIPSET_INIT_FAILURE_PC, DIAG_SEVERITY_ERR);
+		goto cleanup;
+	}
+
+	memset(&g_chipset_msg_hdr, 0, sizeof(struct controlvm_message_header));
+
+	/* if booting in a crash kernel */
+	if (is_kdump_kernel())
+		INIT_DELAYED_WORK(&periodic_controlvm_work,
+				  setup_crash_devices_work_queue);
+	else
+		INIT_DELAYED_WORK(&periodic_controlvm_work,
+				  controlvm_periodic_work);
+	periodic_controlvm_workqueue =
+	    create_singlethread_workqueue("visorchipset_controlvm");
+
+	if (!periodic_controlvm_workqueue) {
+		POSTCODE_LINUX_2(CREATE_WORKQUEUE_FAILED_PC,
+				 DIAG_SEVERITY_ERR);
+		rc = -ENOMEM;
+		goto cleanup;
+	}
+	most_recent_message_jiffies = jiffies;
+	poll_jiffies = POLLJIFFIES_CONTROLVMCHANNEL_FAST;
+	rc = queue_delayed_work(periodic_controlvm_workqueue,
+				&periodic_controlvm_work, poll_jiffies);
+	if (rc < 0) {
+		POSTCODE_LINUX_2(QUEUE_DELAYED_WORK_PC,
+				 DIAG_SEVERITY_ERR);
+		goto cleanup;
+	}
+
+	visorchipset_platform_device.dev.devt = major_dev;
+	if (platform_device_register(&visorchipset_platform_device) < 0) {
+		POSTCODE_LINUX_2(DEVICE_REGISTER_FAILURE_PC, DIAG_SEVERITY_ERR);
+		rc = -1;
+		goto cleanup;
+	}
+	POSTCODE_LINUX_2(CHIPSET_INIT_SUCCESS_PC, POSTCODE_SEVERITY_INFO);
+
+	rc = visorbus_init();
+cleanup:
+	if (rc) {
+		POSTCODE_LINUX_3(CHIPSET_INIT_FAILURE_PC, rc,
+				 POSTCODE_SEVERITY_ERR);
+	}
+	return rc;
+}
+
+static void
+visorchipset_file_cleanup(dev_t major_dev)
+{
+	if (file_cdev.ops)
+		cdev_del(&file_cdev);
+	file_cdev.ops = NULL;
+	unregister_chrdev_region(major_dev, 1);
+}
+
+static int
+visorchipset_exit(struct acpi_device *acpi_device)
+{
+	POSTCODE_LINUX_2(DRIVER_EXIT_PC, POSTCODE_SEVERITY_INFO);
+
+	visorbus_exit();
+
+	cancel_delayed_work(&periodic_controlvm_work);
+	flush_workqueue(periodic_controlvm_workqueue);
+	destroy_workqueue(periodic_controlvm_workqueue);
+	periodic_controlvm_workqueue = NULL;
+	destroy_controlvm_payload_info(&controlvm_payload_info);
+
+	memset(&g_chipset_msg_hdr, 0, sizeof(struct controlvm_message_header));
+
+	visorchannel_destroy(controlvm_channel);
+
+	visorchipset_file_cleanup(visorchipset_platform_device.dev.devt);
+	platform_device_unregister(&visorchipset_platform_device);
+	POSTCODE_LINUX_2(DRIVER_EXIT_PC, POSTCODE_SEVERITY_INFO);
+
+	return 0;
+}
+
+static const struct acpi_device_id unisys_device_ids[] = {
+	{"PNP0A07", 0},
+	{"", 0},
+};
+
+static struct acpi_driver unisys_acpi_driver = {
+	.name = "unisys_acpi",
+	.class = "unisys_acpi_class",
+	.owner = THIS_MODULE,
+	.ids = unisys_device_ids,
+	.ops = {
+		.add = visorchipset_init,
+		.remove = visorchipset_exit,
+		},
+};
+static __init uint32_t visorutil_spar_detect(void)
+{
+	unsigned int eax, ebx, ecx, edx;
+
+	if (cpu_has_hypervisor) {
+		/* check the ID */
+		cpuid(UNISYS_SPAR_LEAF_ID, &eax, &ebx, &ecx, &edx);
+		return  (ebx == UNISYS_SPAR_ID_EBX) &&
+			(ecx == UNISYS_SPAR_ID_ECX) &&
+			(edx == UNISYS_SPAR_ID_EDX);
+	} else {
+		return 0;
+	}
+}
+
+static int init_unisys(void)
+{
+	int result;
+
+	if (!visorutil_spar_detect())
+		return -ENODEV;
+
+	result = acpi_bus_register_driver(&unisys_acpi_driver);
+	if (result)
+		return -ENODEV;
+
+	pr_info("Unisys Visorchipset Driver Loaded.\n");
+	return 0;
+};
+
+static void exit_unisys(void)
+{
+	acpi_bus_unregister_driver(&unisys_acpi_driver);
+}
+
+module_param_named(major, visorchipset_major, int, S_IRUGO);
+MODULE_PARM_DESC(visorchipset_major,
+		 "major device number to use for the device node");
+module_param_named(visorbusregwait, visorchipset_visorbusregwait, int, S_IRUGO);
+MODULE_PARM_DESC(visorchipset_visorbusreqwait,
+		 "1 to have the module wait for the visor bus to register");
+module_param_named(holdchipsetready, visorchipset_holdchipsetready,
+		   int, S_IRUGO);
+MODULE_PARM_DESC(visorchipset_holdchipsetready,
+		 "1 to hold response to CHIPSET_READY");
+
+module_init(init_unisys);
+module_exit(exit_unisys);
+
+MODULE_AUTHOR("Unisys");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Supervisor chipset driver for service partition: ver "
+		   VERSION);
+MODULE_VERSION(VERSION);