diff options
Diffstat (limited to 'drivers/scsi/storvsc_drv.c')
| -rw-r--r-- | drivers/scsi/storvsc_drv.c | 1935 |
1 files changed, 1935 insertions, 0 deletions
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c new file mode 100644 index 000000000..3c6584ff6 --- /dev/null +++ b/drivers/scsi/storvsc_drv.c @@ -0,0 +1,1935 @@ +/* + * 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> + */ + +#include <linux/kernel.h> +#include <linux/wait.h> +#include <linux/sched.h> +#include <linux/completion.h> +#include <linux/string.h> +#include <linux/mm.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/hyperv.h> +#include <linux/blkdev.h> +#include <scsi/scsi.h> +#include <scsi/scsi_cmnd.h> +#include <scsi/scsi_host.h> +#include <scsi/scsi_device.h> +#include <scsi/scsi_tcq.h> +#include <scsi/scsi_eh.h> +#include <scsi/scsi_devinfo.h> +#include <scsi/scsi_dbg.h> + +/* + * All wire protocol details (storage protocol between the guest and the host) + * are consolidated here. + * + * Begin protocol definitions. + */ + +/* + * Version history: + * V1 Beta: 0.1 + * V1 RC < 2008/1/31: 1.0 + * V1 RC > 2008/1/31: 2.0 + * Win7: 4.2 + * Win8: 5.1 + */ + + +#define VMSTOR_WIN7_MAJOR 4 +#define VMSTOR_WIN7_MINOR 2 + +#define VMSTOR_WIN8_MAJOR 5 +#define VMSTOR_WIN8_MINOR 1 + + +/* Packet structure describing virtual storage requests. */ +enum vstor_packet_operation { + VSTOR_OPERATION_COMPLETE_IO = 1, + VSTOR_OPERATION_REMOVE_DEVICE = 2, + VSTOR_OPERATION_EXECUTE_SRB = 3, + VSTOR_OPERATION_RESET_LUN = 4, + VSTOR_OPERATION_RESET_ADAPTER = 5, + VSTOR_OPERATION_RESET_BUS = 6, + VSTOR_OPERATION_BEGIN_INITIALIZATION = 7, + VSTOR_OPERATION_END_INITIALIZATION = 8, + VSTOR_OPERATION_QUERY_PROTOCOL_VERSION = 9, + VSTOR_OPERATION_QUERY_PROPERTIES = 10, + VSTOR_OPERATION_ENUMERATE_BUS = 11, + VSTOR_OPERATION_FCHBA_DATA = 12, + VSTOR_OPERATION_CREATE_SUB_CHANNELS = 13, + VSTOR_OPERATION_MAXIMUM = 13 +}; + +/* + * WWN packet for Fibre Channel HBA + */ + +struct hv_fc_wwn_packet { + bool primary_active; + u8 reserved1; + u8 reserved2; + u8 primary_port_wwn[8]; + u8 primary_node_wwn[8]; + u8 secondary_port_wwn[8]; + u8 secondary_node_wwn[8]; +}; + + + +/* + * SRB Flag Bits + */ + +#define SRB_FLAGS_QUEUE_ACTION_ENABLE 0x00000002 +#define SRB_FLAGS_DISABLE_DISCONNECT 0x00000004 +#define SRB_FLAGS_DISABLE_SYNCH_TRANSFER 0x00000008 +#define SRB_FLAGS_BYPASS_FROZEN_QUEUE 0x00000010 +#define SRB_FLAGS_DISABLE_AUTOSENSE 0x00000020 +#define SRB_FLAGS_DATA_IN 0x00000040 +#define SRB_FLAGS_DATA_OUT 0x00000080 +#define SRB_FLAGS_NO_DATA_TRANSFER 0x00000000 +#define SRB_FLAGS_UNSPECIFIED_DIRECTION (SRB_FLAGS_DATA_IN | SRB_FLAGS_DATA_OUT) +#define SRB_FLAGS_NO_QUEUE_FREEZE 0x00000100 +#define SRB_FLAGS_ADAPTER_CACHE_ENABLE 0x00000200 +#define SRB_FLAGS_FREE_SENSE_BUFFER 0x00000400 + +/* + * This flag indicates the request is part of the workflow for processing a D3. + */ +#define SRB_FLAGS_D3_PROCESSING 0x00000800 +#define SRB_FLAGS_IS_ACTIVE 0x00010000 +#define SRB_FLAGS_ALLOCATED_FROM_ZONE 0x00020000 +#define SRB_FLAGS_SGLIST_FROM_POOL 0x00040000 +#define SRB_FLAGS_BYPASS_LOCKED_QUEUE 0x00080000 +#define SRB_FLAGS_NO_KEEP_AWAKE 0x00100000 +#define SRB_FLAGS_PORT_DRIVER_ALLOCSENSE 0x00200000 +#define SRB_FLAGS_PORT_DRIVER_SENSEHASPORT 0x00400000 +#define SRB_FLAGS_DONT_START_NEXT_PACKET 0x00800000 +#define SRB_FLAGS_PORT_DRIVER_RESERVED 0x0F000000 +#define SRB_FLAGS_CLASS_DRIVER_RESERVED 0xF0000000 + + +/* + * Platform neutral description of a scsi request - + * this remains the same across the write regardless of 32/64 bit + * note: it's patterned off the SCSI_PASS_THROUGH structure + */ +#define STORVSC_MAX_CMD_LEN 0x10 + +#define POST_WIN7_STORVSC_SENSE_BUFFER_SIZE 0x14 +#define PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE 0x12 + +#define STORVSC_SENSE_BUFFER_SIZE 0x14 +#define STORVSC_MAX_BUF_LEN_WITH_PADDING 0x14 + +/* + * Sense buffer size changed in win8; have a run-time + * variable to track the size we should use. + */ +static int sense_buffer_size; + +/* + * The size of the vmscsi_request has changed in win8. The + * additional size is because of new elements added to the + * structure. These elements are valid only when we are talking + * to a win8 host. + * Track the correction to size we need to apply. + */ + +static int vmscsi_size_delta; +static int vmstor_current_major; +static int vmstor_current_minor; + +struct vmscsi_win8_extension { + /* + * The following were added in Windows 8 + */ + u16 reserve; + u8 queue_tag; + u8 queue_action; + u32 srb_flags; + u32 time_out_value; + u32 queue_sort_ey; +} __packed; + +struct vmscsi_request { + u16 length; + u8 srb_status; + u8 scsi_status; + + u8 port_number; + u8 path_id; + u8 target_id; + u8 lun; + + u8 cdb_length; + u8 sense_info_length; + u8 data_in; + u8 reserved; + + u32 data_transfer_length; + + union { + u8 cdb[STORVSC_MAX_CMD_LEN]; + u8 sense_data[STORVSC_SENSE_BUFFER_SIZE]; + u8 reserved_array[STORVSC_MAX_BUF_LEN_WITH_PADDING]; + }; + /* + * The following was added in win8. + */ + struct vmscsi_win8_extension win8_extension; + +} __attribute((packed)); + + +/* + * This structure is sent during the intialization phase to get the different + * properties of the channel. + */ + +#define STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL 0x1 + +struct vmstorage_channel_properties { + u32 reserved; + u16 max_channel_cnt; + u16 reserved1; + + u32 flags; + u32 max_transfer_bytes; + + u64 reserved2; +} __packed; + +/* This structure is sent during the storage protocol negotiations. */ +struct vmstorage_protocol_version { + /* Major (MSW) and minor (LSW) version numbers. */ + u16 major_minor; + + /* + * Revision number is auto-incremented whenever this file is changed + * (See FILL_VMSTOR_REVISION macro above). Mismatch does not + * definitely indicate incompatibility--but it does indicate mismatched + * builds. + * This is only used on the windows side. Just set it to 0. + */ + u16 revision; +} __packed; + +/* Channel Property Flags */ +#define STORAGE_CHANNEL_REMOVABLE_FLAG 0x1 +#define STORAGE_CHANNEL_EMULATED_IDE_FLAG 0x2 + +struct vstor_packet { + /* Requested operation type */ + enum vstor_packet_operation operation; + + /* Flags - see below for values */ + u32 flags; + + /* Status of the request returned from the server side. */ + u32 status; + + /* Data payload area */ + union { + /* + * Structure used to forward SCSI commands from the + * client to the server. + */ + struct vmscsi_request vm_srb; + + /* Structure used to query channel properties. */ + struct vmstorage_channel_properties storage_channel_properties; + + /* Used during version negotiations. */ + struct vmstorage_protocol_version version; + + /* Fibre channel address packet */ + struct hv_fc_wwn_packet wwn_packet; + + /* Number of sub-channels to create */ + u16 sub_channel_count; + + /* This will be the maximum of the union members */ + u8 buffer[0x34]; + }; +} __packed; + +/* + * Packet Flags: + * + * This flag indicates that the server should send back a completion for this + * packet. + */ + +#define REQUEST_COMPLETION_FLAG 0x1 + +/* Matches Windows-end */ +enum storvsc_request_type { + WRITE_TYPE = 0, + READ_TYPE, + UNKNOWN_TYPE, +}; + +/* + * SRB status codes and masks; a subset of the codes used here. + */ + +#define SRB_STATUS_AUTOSENSE_VALID 0x80 +#define SRB_STATUS_INVALID_LUN 0x20 +#define SRB_STATUS_SUCCESS 0x01 +#define SRB_STATUS_ABORTED 0x02 +#define SRB_STATUS_ERROR 0x04 + +/* + * This is the end of Protocol specific defines. + */ + +static int storvsc_ringbuffer_size = (256 * PAGE_SIZE); +static u32 max_outstanding_req_per_channel; + +static int storvsc_vcpus_per_sub_channel = 4; + +module_param(storvsc_ringbuffer_size, int, S_IRUGO); +MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)"); + +module_param(storvsc_vcpus_per_sub_channel, int, S_IRUGO); +MODULE_PARM_DESC(vcpus_per_sub_channel, "Ratio of VCPUs to subchannels"); +/* + * Timeout in seconds for all devices managed by this driver. + */ +static int storvsc_timeout = 180; + +static int msft_blist_flags = BLIST_TRY_VPD_PAGES; + + +static void storvsc_on_channel_callback(void *context); + +#define STORVSC_MAX_LUNS_PER_TARGET 255 +#define STORVSC_MAX_TARGETS 2 +#define STORVSC_MAX_CHANNELS 8 + +#define STORVSC_FC_MAX_LUNS_PER_TARGET 255 +#define STORVSC_FC_MAX_TARGETS 128 +#define STORVSC_FC_MAX_CHANNELS 8 + +#define STORVSC_IDE_MAX_LUNS_PER_TARGET 64 +#define STORVSC_IDE_MAX_TARGETS 1 +#define STORVSC_IDE_MAX_CHANNELS 1 + +struct storvsc_cmd_request { + struct scsi_cmnd *cmd; + + unsigned int bounce_sgl_count; + struct scatterlist *bounce_sgl; + + struct hv_device *device; + + /* Synchronize the request/response if needed */ + struct completion wait_event; + + struct vmbus_channel_packet_multipage_buffer mpb; + struct vmbus_packet_mpb_array *payload; + u32 payload_sz; + + struct vstor_packet vstor_packet; +}; + + +/* A storvsc device is a device object that contains a vmbus channel */ +struct storvsc_device { + struct hv_device *device; + + bool destroy; + bool drain_notify; + bool open_sub_channel; + atomic_t num_outstanding_req; + struct Scsi_Host *host; + + wait_queue_head_t waiting_to_drain; + + /* + * Each unique Port/Path/Target represents 1 channel ie scsi + * controller. In reality, the pathid, targetid is always 0 + * and the port is set by us + */ + unsigned int port_number; + unsigned char path_id; + unsigned char target_id; + + /* + * Max I/O, the device can support. + */ + u32 max_transfer_bytes; + /* Used for vsc/vsp channel reset process */ + struct storvsc_cmd_request init_request; + struct storvsc_cmd_request reset_request; +}; + +struct hv_host_device { + struct hv_device *dev; + unsigned int port; + unsigned char path; + unsigned char target; +}; + +struct storvsc_scan_work { + struct work_struct work; + struct Scsi_Host *host; + uint lun; +}; + +static void storvsc_device_scan(struct work_struct *work) +{ + struct storvsc_scan_work *wrk; + uint lun; + struct scsi_device *sdev; + + wrk = container_of(work, struct storvsc_scan_work, work); + lun = wrk->lun; + + sdev = scsi_device_lookup(wrk->host, 0, 0, lun); + if (!sdev) + goto done; + scsi_rescan_device(&sdev->sdev_gendev); + scsi_device_put(sdev); + +done: + kfree(wrk); +} + +static void storvsc_host_scan(struct work_struct *work) +{ + struct storvsc_scan_work *wrk; + struct Scsi_Host *host; + struct scsi_device *sdev; + unsigned long flags; + + wrk = container_of(work, struct storvsc_scan_work, work); + host = wrk->host; + + /* + * Before scanning the host, first check to see if any of the + * currrently known devices have been hot removed. We issue a + * "unit ready" command against all currently known devices. + * This I/O will result in an error for devices that have been + * removed. As part of handling the I/O error, we remove the device. + * + * When a LUN is added or removed, the host sends us a signal to + * scan the host. Thus we are forced to discover the LUNs that + * may have been removed this way. + */ + mutex_lock(&host->scan_mutex); + spin_lock_irqsave(host->host_lock, flags); + list_for_each_entry(sdev, &host->__devices, siblings) { + spin_unlock_irqrestore(host->host_lock, flags); + scsi_test_unit_ready(sdev, 1, 1, NULL); + spin_lock_irqsave(host->host_lock, flags); + continue; + } + spin_unlock_irqrestore(host->host_lock, flags); + mutex_unlock(&host->scan_mutex); + /* + * Now scan the host to discover LUNs that may have been added. + */ + scsi_scan_host(host); + + kfree(wrk); +} + +static void storvsc_remove_lun(struct work_struct *work) +{ + struct storvsc_scan_work *wrk; + struct scsi_device *sdev; + + wrk = container_of(work, struct storvsc_scan_work, work); + if (!scsi_host_get(wrk->host)) + goto done; + + sdev = scsi_device_lookup(wrk->host, 0, 0, wrk->lun); + + if (sdev) { + scsi_remove_device(sdev); + scsi_device_put(sdev); + } + scsi_host_put(wrk->host); + +done: + kfree(wrk); +} + +/* + * Major/minor macros. Minor version is in LSB, meaning that earlier flat + * version numbers will be interpreted as "0.x" (i.e., 1 becomes 0.1). + */ + +static inline u16 storvsc_get_version(u8 major, u8 minor) +{ + u16 version; + + version = ((major << 8) | minor); + return version; +} + +/* + * We can get incoming messages from the host that are not in response to + * messages that we have sent out. An example of this would be messages + * received by the guest to notify dynamic addition/removal of LUNs. To + * deal with potential race conditions where the driver may be in the + * midst of being unloaded when we might receive an unsolicited message + * from the host, we have implemented a mechanism to gurantee sequential + * consistency: + * + * 1) Once the device is marked as being destroyed, we will fail all + * outgoing messages. + * 2) We permit incoming messages when the device is being destroyed, + * only to properly account for messages already sent out. + */ + +static inline struct storvsc_device *get_out_stor_device( + struct hv_device *device) +{ + struct storvsc_device *stor_device; + + stor_device = hv_get_drvdata(device); + + if (stor_device && stor_device->destroy) + stor_device = NULL; + + return stor_device; +} + + +static inline void storvsc_wait_to_drain(struct storvsc_device *dev) +{ + dev->drain_notify = true; + wait_event(dev->waiting_to_drain, + atomic_read(&dev->num_outstanding_req) == 0); + dev->drain_notify = false; +} + +static inline struct storvsc_device *get_in_stor_device( + struct hv_device *device) +{ + struct storvsc_device *stor_device; + + stor_device = hv_get_drvdata(device); + + if (!stor_device) + goto get_in_err; + + /* + * If the device is being destroyed; allow incoming + * traffic only to cleanup outstanding requests. + */ + + if (stor_device->destroy && + (atomic_read(&stor_device->num_outstanding_req) == 0)) + stor_device = NULL; + +get_in_err: + return stor_device; + +} + +static void destroy_bounce_buffer(struct scatterlist *sgl, + unsigned int sg_count) +{ + int i; + struct page *page_buf; + + for (i = 0; i < sg_count; i++) { + page_buf = sg_page((&sgl[i])); + if (page_buf != NULL) + __free_page(page_buf); + } + + kfree(sgl); +} + +static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count) +{ + int i; + + /* No need to check */ + if (sg_count < 2) + return -1; + + /* We have at least 2 sg entries */ + for (i = 0; i < sg_count; i++) { + if (i == 0) { + /* make sure 1st one does not have hole */ + if (sgl[i].offset + sgl[i].length != PAGE_SIZE) + return i; + } else if (i == sg_count - 1) { + /* make sure last one does not have hole */ + if (sgl[i].offset != 0) + return i; + } else { + /* make sure no hole in the middle */ + if (sgl[i].length != PAGE_SIZE || sgl[i].offset != 0) + return i; + } + } + return -1; +} + +static struct scatterlist *create_bounce_buffer(struct scatterlist *sgl, + unsigned int sg_count, + unsigned int len, + int write) +{ + int i; + int num_pages; + struct scatterlist *bounce_sgl; + struct page *page_buf; + unsigned int buf_len = ((write == WRITE_TYPE) ? 0 : PAGE_SIZE); + + num_pages = ALIGN(len, PAGE_SIZE) >> PAGE_SHIFT; + + bounce_sgl = kcalloc(num_pages, sizeof(struct scatterlist), GFP_ATOMIC); + if (!bounce_sgl) + return NULL; + + sg_init_table(bounce_sgl, num_pages); + for (i = 0; i < num_pages; i++) { + page_buf = alloc_page(GFP_ATOMIC); + if (!page_buf) + goto cleanup; + sg_set_page(&bounce_sgl[i], page_buf, buf_len, 0); + } + + return bounce_sgl; + +cleanup: + destroy_bounce_buffer(bounce_sgl, num_pages); + return NULL; +} + +/* Assume the original sgl has enough room */ +static unsigned int copy_from_bounce_buffer(struct scatterlist *orig_sgl, + struct scatterlist *bounce_sgl, + unsigned int orig_sgl_count, + unsigned int bounce_sgl_count) +{ + int i; + int j = 0; + unsigned long src, dest; + unsigned int srclen, destlen, copylen; + unsigned int total_copied = 0; + unsigned long bounce_addr = 0; + unsigned long dest_addr = 0; + unsigned long flags; + struct scatterlist *cur_dest_sgl; + struct scatterlist *cur_src_sgl; + + local_irq_save(flags); + cur_dest_sgl = orig_sgl; + cur_src_sgl = bounce_sgl; + for (i = 0; i < orig_sgl_count; i++) { + dest_addr = (unsigned long) + kmap_atomic(sg_page(cur_dest_sgl)) + + cur_dest_sgl->offset; + dest = dest_addr; + destlen = cur_dest_sgl->length; + + if (bounce_addr == 0) + bounce_addr = (unsigned long)kmap_atomic( + sg_page(cur_src_sgl)); + + while (destlen) { + src = bounce_addr + cur_src_sgl->offset; + srclen = cur_src_sgl->length - cur_src_sgl->offset; + + copylen = min(srclen, destlen); + memcpy((void *)dest, (void *)src, copylen); + + total_copied += copylen; + cur_src_sgl->offset += copylen; + destlen -= copylen; + dest += copylen; + + if (cur_src_sgl->offset == cur_src_sgl->length) { + /* full */ + kunmap_atomic((void *)bounce_addr); + j++; + + /* + * It is possible that the number of elements + * in the bounce buffer may not be equal to + * the number of elements in the original + * scatter list. Handle this correctly. + */ + + if (j == bounce_sgl_count) { + /* + * We are done; cleanup and return. + */ + kunmap_atomic((void *)(dest_addr - + cur_dest_sgl->offset)); + local_irq_restore(flags); + return total_copied; + } + + /* if we need to use another bounce buffer */ + if (destlen || i != orig_sgl_count - 1) { + cur_src_sgl = sg_next(cur_src_sgl); + bounce_addr = (unsigned long) + kmap_atomic( + sg_page(cur_src_sgl)); + } + } else if (destlen == 0 && i == orig_sgl_count - 1) { + /* unmap the last bounce that is < PAGE_SIZE */ + kunmap_atomic((void *)bounce_addr); + } + } + + kunmap_atomic((void *)(dest_addr - cur_dest_sgl->offset)); + cur_dest_sgl = sg_next(cur_dest_sgl); + } + + local_irq_restore(flags); + + return total_copied; +} + +/* Assume the bounce_sgl has enough room ie using the create_bounce_buffer() */ +static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl, + struct scatterlist *bounce_sgl, + unsigned int orig_sgl_count) +{ + int i; + int j = 0; + unsigned long src, dest; + unsigned int srclen, destlen, copylen; + unsigned int total_copied = 0; + unsigned long bounce_addr = 0; + unsigned long src_addr = 0; + unsigned long flags; + struct scatterlist *cur_src_sgl; + struct scatterlist *cur_dest_sgl; + + local_irq_save(flags); + + cur_src_sgl = orig_sgl; + cur_dest_sgl = bounce_sgl; + + for (i = 0; i < orig_sgl_count; i++) { + src_addr = (unsigned long) + kmap_atomic(sg_page(cur_src_sgl)) + + cur_src_sgl->offset; + src = src_addr; + srclen = cur_src_sgl->length; + + if (bounce_addr == 0) + bounce_addr = (unsigned long) + kmap_atomic(sg_page(cur_dest_sgl)); + + while (srclen) { + /* assume bounce offset always == 0 */ + dest = bounce_addr + cur_dest_sgl->length; + destlen = PAGE_SIZE - cur_dest_sgl->length; + + copylen = min(srclen, destlen); + memcpy((void *)dest, (void *)src, copylen); + + total_copied += copylen; + cur_dest_sgl->length += copylen; + srclen -= copylen; + src += copylen; + + if (cur_dest_sgl->length == PAGE_SIZE) { + /* full..move to next entry */ + kunmap_atomic((void *)bounce_addr); + bounce_addr = 0; + j++; + } + + /* if we need to use another bounce buffer */ + if (srclen && bounce_addr == 0) { + cur_dest_sgl = sg_next(cur_dest_sgl); + bounce_addr = (unsigned long) + kmap_atomic( + sg_page(cur_dest_sgl)); + } + + } + + kunmap_atomic((void *)(src_addr - cur_src_sgl->offset)); + cur_src_sgl = sg_next(cur_src_sgl); + } + + if (bounce_addr) + kunmap_atomic((void *)bounce_addr); + + local_irq_restore(flags); + + return total_copied; +} + +static void handle_sc_creation(struct vmbus_channel *new_sc) +{ + struct hv_device *device = new_sc->primary_channel->device_obj; + struct storvsc_device *stor_device; + struct vmstorage_channel_properties props; + + stor_device = get_out_stor_device(device); + if (!stor_device) + return; + + if (stor_device->open_sub_channel == false) + return; + + memset(&props, 0, sizeof(struct vmstorage_channel_properties)); + + vmbus_open(new_sc, + storvsc_ringbuffer_size, + storvsc_ringbuffer_size, + (void *)&props, + sizeof(struct vmstorage_channel_properties), + storvsc_on_channel_callback, new_sc); +} + +static void handle_multichannel_storage(struct hv_device *device, int max_chns) +{ + struct storvsc_device *stor_device; + int num_cpus = num_online_cpus(); + int num_sc; + struct storvsc_cmd_request *request; + struct vstor_packet *vstor_packet; + int ret, t; + + num_sc = ((max_chns > num_cpus) ? num_cpus : max_chns); + stor_device = get_out_stor_device(device); + if (!stor_device) + return; + + request = &stor_device->init_request; + vstor_packet = &request->vstor_packet; + + stor_device->open_sub_channel = true; + /* + * Establish a handler for dealing with subchannels. + */ + vmbus_set_sc_create_callback(device->channel, handle_sc_creation); + + /* + * Check to see if sub-channels have already been created. This + * can happen when this driver is re-loaded after unloading. + */ + + if (vmbus_are_subchannels_present(device->channel)) + return; + + stor_device->open_sub_channel = false; + /* + * Request the host to create sub-channels. + */ + memset(request, 0, sizeof(struct storvsc_cmd_request)); + init_completion(&request->wait_event); + vstor_packet->operation = VSTOR_OPERATION_CREATE_SUB_CHANNELS; + vstor_packet->flags = REQUEST_COMPLETION_FLAG; + vstor_packet->sub_channel_count = num_sc; + + ret = vmbus_sendpacket(device->channel, vstor_packet, + (sizeof(struct vstor_packet) - + vmscsi_size_delta), + (unsigned long)request, + VM_PKT_DATA_INBAND, + VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + + if (ret != 0) + return; + + t = wait_for_completion_timeout(&request->wait_event, 10*HZ); + if (t == 0) + return; + + if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO || + vstor_packet->status != 0) + return; + + /* + * Now that we created the sub-channels, invoke the check; this + * may trigger the callback. + */ + stor_device->open_sub_channel = true; + vmbus_are_subchannels_present(device->channel); +} + +static int storvsc_channel_init(struct hv_device *device) +{ + struct storvsc_device *stor_device; + struct storvsc_cmd_request *request; + struct vstor_packet *vstor_packet; + int ret, t; + int max_chns; + bool process_sub_channels = false; + + stor_device = get_out_stor_device(device); + if (!stor_device) + return -ENODEV; + + request = &stor_device->init_request; + vstor_packet = &request->vstor_packet; + + /* + * Now, initiate the vsc/vsp initialization protocol on the open + * channel + */ + memset(request, 0, sizeof(struct storvsc_cmd_request)); + init_completion(&request->wait_event); + vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION; + vstor_packet->flags = REQUEST_COMPLETION_FLAG; + + ret = vmbus_sendpacket(device->channel, vstor_packet, + (sizeof(struct vstor_packet) - + vmscsi_size_delta), + (unsigned long)request, + VM_PKT_DATA_INBAND, + VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + if (ret != 0) + goto cleanup; + + t = wait_for_completion_timeout(&request->wait_event, 5*HZ); + if (t == 0) { + ret = -ETIMEDOUT; + goto cleanup; + } + + if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO || + vstor_packet->status != 0) + goto cleanup; + + + /* reuse the packet for version range supported */ + memset(vstor_packet, 0, sizeof(struct vstor_packet)); + vstor_packet->operation = VSTOR_OPERATION_QUERY_PROTOCOL_VERSION; + vstor_packet->flags = REQUEST_COMPLETION_FLAG; + + vstor_packet->version.major_minor = + storvsc_get_version(vmstor_current_major, vmstor_current_minor); + + /* + * The revision number is only used in Windows; set it to 0. + */ + vstor_packet->version.revision = 0; + + ret = vmbus_sendpacket(device->channel, vstor_packet, + (sizeof(struct vstor_packet) - + vmscsi_size_delta), + (unsigned long)request, + VM_PKT_DATA_INBAND, + VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + if (ret != 0) + goto cleanup; + + t = wait_for_completion_timeout(&request->wait_event, 5*HZ); + if (t == 0) { + ret = -ETIMEDOUT; + goto cleanup; + } + + if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO || + vstor_packet->status != 0) + goto cleanup; + + + memset(vstor_packet, 0, sizeof(struct vstor_packet)); + vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES; + vstor_packet->flags = REQUEST_COMPLETION_FLAG; + + ret = vmbus_sendpacket(device->channel, vstor_packet, + (sizeof(struct vstor_packet) - + vmscsi_size_delta), + (unsigned long)request, + VM_PKT_DATA_INBAND, + VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + + if (ret != 0) + goto cleanup; + + t = wait_for_completion_timeout(&request->wait_event, 5*HZ); + if (t == 0) { + ret = -ETIMEDOUT; + goto cleanup; + } + + if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO || + vstor_packet->status != 0) + goto cleanup; + + /* + * Check to see if multi-channel support is there. + * Hosts that implement protocol version of 5.1 and above + * support multi-channel. + */ + max_chns = vstor_packet->storage_channel_properties.max_channel_cnt; + if ((vmbus_proto_version != VERSION_WIN7) && + (vmbus_proto_version != VERSION_WS2008)) { + if (vstor_packet->storage_channel_properties.flags & + STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL) + process_sub_channels = true; + } + stor_device->max_transfer_bytes = + vstor_packet->storage_channel_properties.max_transfer_bytes; + + memset(vstor_packet, 0, sizeof(struct vstor_packet)); + vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION; + vstor_packet->flags = REQUEST_COMPLETION_FLAG; + + ret = vmbus_sendpacket(device->channel, vstor_packet, + (sizeof(struct vstor_packet) - + vmscsi_size_delta), + (unsigned long)request, + VM_PKT_DATA_INBAND, + VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + + if (ret != 0) + goto cleanup; + + t = wait_for_completion_timeout(&request->wait_event, 5*HZ); + if (t == 0) { + ret = -ETIMEDOUT; + goto cleanup; + } + + if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO || + vstor_packet->status != 0) + goto cleanup; + + if (process_sub_channels) + handle_multichannel_storage(device, max_chns); + + +cleanup: + return ret; +} + +static void storvsc_handle_error(struct vmscsi_request *vm_srb, + struct scsi_cmnd *scmnd, + struct Scsi_Host *host, + u8 asc, u8 ascq) +{ + struct storvsc_scan_work *wrk; + void (*process_err_fn)(struct work_struct *work); + bool do_work = false; + + switch (vm_srb->srb_status) { + case SRB_STATUS_ERROR: + /* + * If there is an error; offline the device since all + * error recovery strategies would have already been + * deployed on the host side. However, if the command + * were a pass-through command deal with it appropriately. + */ + switch (scmnd->cmnd[0]) { + case ATA_16: + case ATA_12: + set_host_byte(scmnd, DID_PASSTHROUGH); + break; + /* + * On Some Windows hosts TEST_UNIT_READY command can return + * SRB_STATUS_ERROR, let the upper level code deal with it + * based on the sense information. + */ + case TEST_UNIT_READY: + break; + default: + set_host_byte(scmnd, DID_TARGET_FAILURE); + } + break; + case SRB_STATUS_INVALID_LUN: + do_work = true; + process_err_fn = storvsc_remove_lun; + break; + case (SRB_STATUS_ABORTED | SRB_STATUS_AUTOSENSE_VALID): + if ((asc == 0x2a) && (ascq == 0x9)) { + do_work = true; + process_err_fn = storvsc_device_scan; + /* + * Retry the I/O that trigerred this. + */ + set_host_byte(scmnd, DID_REQUEUE); + } + break; + } + + if (!do_work) + return; + + /* + * We need to schedule work to process this error; schedule it. + */ + wrk = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC); + if (!wrk) { + set_host_byte(scmnd, DID_TARGET_FAILURE); + return; + } + + wrk->host = host; + wrk->lun = vm_srb->lun; + INIT_WORK(&wrk->work, process_err_fn); + schedule_work(&wrk->work); +} + + +static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request) +{ + struct scsi_cmnd *scmnd = cmd_request->cmd; + struct hv_host_device *host_dev = shost_priv(scmnd->device->host); + struct scsi_sense_hdr sense_hdr; + struct vmscsi_request *vm_srb; + struct Scsi_Host *host; + struct storvsc_device *stor_dev; + struct hv_device *dev = host_dev->dev; + u32 payload_sz = cmd_request->payload_sz; + void *payload = cmd_request->payload; + + stor_dev = get_in_stor_device(dev); + host = stor_dev->host; + + vm_srb = &cmd_request->vstor_packet.vm_srb; + if (cmd_request->bounce_sgl_count) { + if (vm_srb->data_in == READ_TYPE) + copy_from_bounce_buffer(scsi_sglist(scmnd), + cmd_request->bounce_sgl, + scsi_sg_count(scmnd), + cmd_request->bounce_sgl_count); + destroy_bounce_buffer(cmd_request->bounce_sgl, + cmd_request->bounce_sgl_count); + } + + scmnd->result = vm_srb->scsi_status; + + if (scmnd->result) { + if (scsi_normalize_sense(scmnd->sense_buffer, + SCSI_SENSE_BUFFERSIZE, &sense_hdr)) + scsi_print_sense_hdr(scmnd->device, "storvsc", + &sense_hdr); + } + + if (vm_srb->srb_status != SRB_STATUS_SUCCESS) + storvsc_handle_error(vm_srb, scmnd, host, sense_hdr.asc, + sense_hdr.ascq); + + scsi_set_resid(scmnd, + cmd_request->payload->range.len - + vm_srb->data_transfer_length); + + scmnd->scsi_done(scmnd); + + if (payload_sz > + sizeof(struct vmbus_channel_packet_multipage_buffer)) + kfree(payload); +} + +static void storvsc_on_io_completion(struct hv_device *device, + struct vstor_packet *vstor_packet, + struct storvsc_cmd_request *request) +{ + struct storvsc_device *stor_device; + struct vstor_packet *stor_pkt; + + stor_device = hv_get_drvdata(device); + stor_pkt = &request->vstor_packet; + + /* + * The current SCSI handling on the host side does + * not correctly handle: + * INQUIRY command with page code parameter set to 0x80 + * MODE_SENSE command with cmd[2] == 0x1c + * + * Setup srb and scsi status so this won't be fatal. + * We do this so we can distinguish truly fatal failues + * (srb status == 0x4) and off-line the device in that case. + */ + + if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) || + (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) { + vstor_packet->vm_srb.scsi_status = 0; + vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS; + } + + + /* Copy over the status...etc */ + stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status; + stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status; + stor_pkt->vm_srb.sense_info_length = + vstor_packet->vm_srb.sense_info_length; + + + if ((vstor_packet->vm_srb.scsi_status & 0xFF) == 0x02) { + /* CHECK_CONDITION */ + if (vstor_packet->vm_srb.srb_status & + SRB_STATUS_AUTOSENSE_VALID) { + /* autosense data available */ + + memcpy(request->cmd->sense_buffer, + vstor_packet->vm_srb.sense_data, + vstor_packet->vm_srb.sense_info_length); + + } + } + + stor_pkt->vm_srb.data_transfer_length = + vstor_packet->vm_srb.data_transfer_length; + + storvsc_command_completion(request); + + if (atomic_dec_and_test(&stor_device->num_outstanding_req) && + stor_device->drain_notify) + wake_up(&stor_device->waiting_to_drain); + + +} + +static void storvsc_on_receive(struct hv_device *device, + struct vstor_packet *vstor_packet, + struct storvsc_cmd_request *request) +{ + struct storvsc_scan_work *work; + struct storvsc_device *stor_device; + + switch (vstor_packet->operation) { + case VSTOR_OPERATION_COMPLETE_IO: + storvsc_on_io_completion(device, vstor_packet, request); + break; + + case VSTOR_OPERATION_REMOVE_DEVICE: + case VSTOR_OPERATION_ENUMERATE_BUS: + stor_device = get_in_stor_device(device); + work = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC); + if (!work) + return; + + INIT_WORK(&work->work, storvsc_host_scan); + work->host = stor_device->host; + schedule_work(&work->work); + break; + + default: + break; + } +} + +static void storvsc_on_channel_callback(void *context) +{ + struct vmbus_channel *channel = (struct vmbus_channel *)context; + struct hv_device *device; + struct storvsc_device *stor_device; + u32 bytes_recvd; + u64 request_id; + unsigned char packet[ALIGN(sizeof(struct vstor_packet), 8)]; + struct storvsc_cmd_request *request; + int ret; + + if (channel->primary_channel != NULL) + device = channel->primary_channel->device_obj; + else + device = channel->device_obj; + + stor_device = get_in_stor_device(device); + if (!stor_device) + return; + + do { + ret = vmbus_recvpacket(channel, packet, + ALIGN((sizeof(struct vstor_packet) - + vmscsi_size_delta), 8), + &bytes_recvd, &request_id); + if (ret == 0 && bytes_recvd > 0) { + + request = (struct storvsc_cmd_request *) + (unsigned long)request_id; + + if ((request == &stor_device->init_request) || + (request == &stor_device->reset_request)) { + + memcpy(&request->vstor_packet, packet, + (sizeof(struct vstor_packet) - + vmscsi_size_delta)); + complete(&request->wait_event); + } else { + storvsc_on_receive(device, + (struct vstor_packet *)packet, + request); + } + } else { + break; + } + } while (1); + + return; +} + +static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size) +{ + struct vmstorage_channel_properties props; + int ret; + + memset(&props, 0, sizeof(struct vmstorage_channel_properties)); + + ret = vmbus_open(device->channel, + ring_size, + ring_size, + (void *)&props, + sizeof(struct vmstorage_channel_properties), + storvsc_on_channel_callback, device->channel); + + if (ret != 0) + return ret; + + ret = storvsc_channel_init(device); + + return ret; +} + +static int storvsc_dev_remove(struct hv_device *device) +{ + struct storvsc_device *stor_device; + unsigned long flags; + + stor_device = hv_get_drvdata(device); + + spin_lock_irqsave(&device->channel->inbound_lock, flags); + stor_device->destroy = true; + spin_unlock_irqrestore(&device->channel->inbound_lock, flags); + + /* + * At this point, all outbound traffic should be disable. We + * only allow inbound traffic (responses) to proceed so that + * outstanding requests can be completed. + */ + + storvsc_wait_to_drain(stor_device); + + /* + * Since we have already drained, we don't need to busy wait + * as was done in final_release_stor_device() + * Note that we cannot set the ext pointer to NULL until + * we have drained - to drain the outgoing packets, we need to + * allow incoming packets. + */ + spin_lock_irqsave(&device->channel->inbound_lock, flags); + hv_set_drvdata(device, NULL); + spin_unlock_irqrestore(&device->channel->inbound_lock, flags); + + /* Close the channel */ + vmbus_close(device->channel); + + kfree(stor_device); + return 0; +} + +static int storvsc_do_io(struct hv_device *device, + struct storvsc_cmd_request *request) +{ + struct storvsc_device *stor_device; + struct vstor_packet *vstor_packet; + struct vmbus_channel *outgoing_channel; + int ret = 0; + + vstor_packet = &request->vstor_packet; + stor_device = get_out_stor_device(device); + + if (!stor_device) + return -ENODEV; + + + request->device = device; + /* + * Select an an appropriate channel to send the request out. + */ + + outgoing_channel = vmbus_get_outgoing_channel(device->channel); + + + vstor_packet->flags |= REQUEST_COMPLETION_FLAG; + + vstor_packet->vm_srb.length = (sizeof(struct vmscsi_request) - + vmscsi_size_delta); + + + vstor_packet->vm_srb.sense_info_length = sense_buffer_size; + + + vstor_packet->vm_srb.data_transfer_length = + request->payload->range.len; + + vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB; + + if (request->payload->range.len) { + + ret = vmbus_sendpacket_mpb_desc(outgoing_channel, + request->payload, request->payload_sz, + vstor_packet, + (sizeof(struct vstor_packet) - + vmscsi_size_delta), + (unsigned long)request); + } else { + ret = vmbus_sendpacket(outgoing_channel, vstor_packet, + (sizeof(struct vstor_packet) - + vmscsi_size_delta), + (unsigned long)request, + VM_PKT_DATA_INBAND, + VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + } + + if (ret != 0) + return ret; + + atomic_inc(&stor_device->num_outstanding_req); + + return ret; +} + +static int storvsc_device_configure(struct scsi_device *sdevice) +{ + + blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE); + + blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY); + + blk_queue_rq_timeout(sdevice->request_queue, (storvsc_timeout * HZ)); + + sdevice->no_write_same = 1; + + /* + * Add blist flags to permit the reading of the VPD pages even when + * the target may claim SPC-2 compliance. MSFT targets currently + * claim SPC-2 compliance while they implement post SPC-2 features. + * With this patch we can correctly handle WRITE_SAME_16 issues. + */ + sdevice->sdev_bflags |= msft_blist_flags; + + /* + * If the host is WIN8 or WIN8 R2, claim conformance to SPC-3 + * if the device is a MSFT virtual device. + */ + if (!strncmp(sdevice->vendor, "Msft", 4)) { + switch (vmbus_proto_version) { + case VERSION_WIN8: + case VERSION_WIN8_1: + sdevice->scsi_level = SCSI_SPC_3; + break; + } + } + + return 0; +} + +static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev, + sector_t capacity, int *info) +{ + sector_t nsect = capacity; + sector_t cylinders = nsect; + int heads, sectors_pt; + + /* + * We are making up these values; let us keep it simple. + */ + heads = 0xff; + sectors_pt = 0x3f; /* Sectors per track */ + sector_div(cylinders, heads * sectors_pt); + if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect) + cylinders = 0xffff; + + info[0] = heads; + info[1] = sectors_pt; + info[2] = (int)cylinders; + + return 0; +} + +static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd) +{ + struct hv_host_device *host_dev = shost_priv(scmnd->device->host); + struct hv_device *device = host_dev->dev; + + struct storvsc_device *stor_device; + struct storvsc_cmd_request *request; + struct vstor_packet *vstor_packet; + int ret, t; + + + stor_device = get_out_stor_device(device); + if (!stor_device) + return FAILED; + + request = &stor_device->reset_request; + vstor_packet = &request->vstor_packet; + + init_completion(&request->wait_event); + + vstor_packet->operation = VSTOR_OPERATION_RESET_BUS; + vstor_packet->flags = REQUEST_COMPLETION_FLAG; + vstor_packet->vm_srb.path_id = stor_device->path_id; + + ret = vmbus_sendpacket(device->channel, vstor_packet, + (sizeof(struct vstor_packet) - + vmscsi_size_delta), + (unsigned long)&stor_device->reset_request, + VM_PKT_DATA_INBAND, + VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); + if (ret != 0) + return FAILED; + + t = wait_for_completion_timeout(&request->wait_event, 5*HZ); + if (t == 0) + return TIMEOUT_ERROR; + + + /* + * At this point, all outstanding requests in the adapter + * should have been flushed out and return to us + * There is a potential race here where the host may be in + * the process of responding when we return from here. + * Just wait for all in-transit packets to be accounted for + * before we return from here. + */ + storvsc_wait_to_drain(stor_device); + + return SUCCESS; +} + +/* + * The host guarantees to respond to each command, although I/O latencies might + * be unbounded on Azure. Reset the timer unconditionally to give the host a + * chance to perform EH. + */ +static enum blk_eh_timer_return storvsc_eh_timed_out(struct scsi_cmnd *scmnd) +{ + return BLK_EH_RESET_TIMER; +} + +static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd) +{ + bool allowed = true; + u8 scsi_op = scmnd->cmnd[0]; + + switch (scsi_op) { + /* the host does not handle WRITE_SAME, log accident usage */ + case WRITE_SAME: + /* + * smartd sends this command and the host does not handle + * this. So, don't send it. + */ + case SET_WINDOW: + scmnd->result = ILLEGAL_REQUEST << 16; + allowed = false; + break; + default: + break; + } + return allowed; +} + +static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd) +{ + int ret; + struct hv_host_device *host_dev = shost_priv(host); + struct hv_device *dev = host_dev->dev; + struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd); + int i; + struct scatterlist *sgl; + unsigned int sg_count = 0; + struct vmscsi_request *vm_srb; + struct scatterlist *cur_sgl; + struct vmbus_packet_mpb_array *payload; + u32 payload_sz; + u32 length; + + if (vmstor_current_major <= VMSTOR_WIN8_MAJOR) { + /* + * On legacy hosts filter unimplemented commands. + * Future hosts are expected to correctly handle + * unsupported commands. Furthermore, it is + * possible that some of the currently + * unsupported commands maybe supported in + * future versions of the host. + */ + if (!storvsc_scsi_cmd_ok(scmnd)) { + scmnd->scsi_done(scmnd); + return 0; + } + } + + /* Setup the cmd request */ + cmd_request->cmd = scmnd; + + vm_srb = &cmd_request->vstor_packet.vm_srb; + vm_srb->win8_extension.time_out_value = 60; + + vm_srb->win8_extension.srb_flags |= + (SRB_FLAGS_QUEUE_ACTION_ENABLE | + SRB_FLAGS_DISABLE_SYNCH_TRANSFER); + + /* Build the SRB */ + switch (scmnd->sc_data_direction) { + case DMA_TO_DEVICE: + vm_srb->data_in = WRITE_TYPE; + vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_OUT; + break; + case DMA_FROM_DEVICE: + vm_srb->data_in = READ_TYPE; + vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_IN; + break; + default: + vm_srb->data_in = UNKNOWN_TYPE; + vm_srb->win8_extension.srb_flags |= SRB_FLAGS_NO_DATA_TRANSFER; + break; + } + + + vm_srb->port_number = host_dev->port; + vm_srb->path_id = scmnd->device->channel; + vm_srb->target_id = scmnd->device->id; + vm_srb->lun = scmnd->device->lun; + + vm_srb->cdb_length = scmnd->cmd_len; + + memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length); + + sgl = (struct scatterlist *)scsi_sglist(scmnd); + sg_count = scsi_sg_count(scmnd); + + length = scsi_bufflen(scmnd); + payload = (struct vmbus_packet_mpb_array *)&cmd_request->mpb; + payload_sz = sizeof(cmd_request->mpb); + + if (sg_count) { + /* check if we need to bounce the sgl */ + if (do_bounce_buffer(sgl, scsi_sg_count(scmnd)) != -1) { + cmd_request->bounce_sgl = + create_bounce_buffer(sgl, sg_count, + length, + vm_srb->data_in); + if (!cmd_request->bounce_sgl) + return SCSI_MLQUEUE_HOST_BUSY; + + cmd_request->bounce_sgl_count = + ALIGN(length, PAGE_SIZE) >> PAGE_SHIFT; + + if (vm_srb->data_in == WRITE_TYPE) + copy_to_bounce_buffer(sgl, + cmd_request->bounce_sgl, sg_count); + + sgl = cmd_request->bounce_sgl; + sg_count = cmd_request->bounce_sgl_count; + } + + + if (sg_count > MAX_PAGE_BUFFER_COUNT) { + + payload_sz = (sg_count * sizeof(void *) + + sizeof(struct vmbus_packet_mpb_array)); + payload = kmalloc(payload_sz, GFP_ATOMIC); + if (!payload) { + if (cmd_request->bounce_sgl_count) + destroy_bounce_buffer( + cmd_request->bounce_sgl, + cmd_request->bounce_sgl_count); + + return SCSI_MLQUEUE_DEVICE_BUSY; + } + } + + payload->range.len = length; + payload->range.offset = sgl[0].offset; + + cur_sgl = sgl; + for (i = 0; i < sg_count; i++) { + payload->range.pfn_array[i] = + page_to_pfn(sg_page((cur_sgl))); + cur_sgl = sg_next(cur_sgl); + } + + } else if (scsi_sglist(scmnd)) { + payload->range.len = length; + payload->range.offset = + virt_to_phys(scsi_sglist(scmnd)) & (PAGE_SIZE-1); + payload->range.pfn_array[0] = + virt_to_phys(scsi_sglist(scmnd)) >> PAGE_SHIFT; + } + + cmd_request->payload = payload; + cmd_request->payload_sz = payload_sz; + + /* Invokes the vsc to start an IO */ + ret = storvsc_do_io(dev, cmd_request); + + if (ret == -EAGAIN) { + /* no more space */ + + if (cmd_request->bounce_sgl_count) + destroy_bounce_buffer(cmd_request->bounce_sgl, + cmd_request->bounce_sgl_count); + + return SCSI_MLQUEUE_DEVICE_BUSY; + } + + return 0; +} + +static struct scsi_host_template scsi_driver = { + .module = THIS_MODULE, + .name = "storvsc_host_t", + .cmd_size = sizeof(struct storvsc_cmd_request), + .bios_param = storvsc_get_chs, + .queuecommand = storvsc_queuecommand, + .eh_host_reset_handler = storvsc_host_reset_handler, + .proc_name = "storvsc_host", + .eh_timed_out = storvsc_eh_timed_out, + .slave_configure = storvsc_device_configure, + .cmd_per_lun = 255, + .this_id = -1, + .use_clustering = ENABLE_CLUSTERING, + /* Make sure we dont get a sg segment crosses a page boundary */ + .dma_boundary = PAGE_SIZE-1, + .no_write_same = 1, +}; + +enum { + SCSI_GUID, + IDE_GUID, + SFC_GUID, +}; + +static const struct hv_vmbus_device_id id_table[] = { + /* SCSI guid */ + { HV_SCSI_GUID, + .driver_data = SCSI_GUID + }, + /* IDE guid */ + { HV_IDE_GUID, + .driver_data = IDE_GUID + }, + /* Fibre Channel GUID */ + { + HV_SYNTHFC_GUID, + .driver_data = SFC_GUID + }, + { }, +}; + +MODULE_DEVICE_TABLE(vmbus, id_table); + +static int storvsc_probe(struct hv_device *device, + const struct hv_vmbus_device_id *dev_id) +{ + int ret; + int num_cpus = num_online_cpus(); + struct Scsi_Host *host; + struct hv_host_device *host_dev; + bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false); + int target = 0; + struct storvsc_device *stor_device; + int max_luns_per_target; + int max_targets; + int max_channels; + int max_sub_channels = 0; + + /* + * Based on the windows host we are running on, + * set state to properly communicate with the host. + */ + + switch (vmbus_proto_version) { + case VERSION_WS2008: + case VERSION_WIN7: + sense_buffer_size = PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE; + vmscsi_size_delta = sizeof(struct vmscsi_win8_extension); + vmstor_current_major = VMSTOR_WIN7_MAJOR; + vmstor_current_minor = VMSTOR_WIN7_MINOR; + max_luns_per_target = STORVSC_IDE_MAX_LUNS_PER_TARGET; + max_targets = STORVSC_IDE_MAX_TARGETS; + max_channels = STORVSC_IDE_MAX_CHANNELS; + break; + default: + sense_buffer_size = POST_WIN7_STORVSC_SENSE_BUFFER_SIZE; + vmscsi_size_delta = 0; + vmstor_current_major = VMSTOR_WIN8_MAJOR; + vmstor_current_minor = VMSTOR_WIN8_MINOR; + max_luns_per_target = STORVSC_MAX_LUNS_PER_TARGET; + max_targets = STORVSC_MAX_TARGETS; + max_channels = STORVSC_MAX_CHANNELS; + /* + * On Windows8 and above, we support sub-channels for storage. + * The number of sub-channels offerred is based on the number of + * VCPUs in the guest. + */ + max_sub_channels = (num_cpus / storvsc_vcpus_per_sub_channel); + break; + } + + scsi_driver.can_queue = (max_outstanding_req_per_channel * + (max_sub_channels + 1)); + + host = scsi_host_alloc(&scsi_driver, + sizeof(struct hv_host_device)); + if (!host) + return -ENOMEM; + + host_dev = shost_priv(host); + memset(host_dev, 0, sizeof(struct hv_host_device)); + + host_dev->port = host->host_no; + host_dev->dev = device; + + + stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL); + if (!stor_device) { + ret = -ENOMEM; + goto err_out0; + } + + stor_device->destroy = false; + stor_device->open_sub_channel = false; + init_waitqueue_head(&stor_device->waiting_to_drain); + stor_device->device = device; + stor_device->host = host; + hv_set_drvdata(device, stor_device); + + stor_device->port_number = host->host_no; + ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size); + if (ret) + goto err_out1; + + host_dev->path = stor_device->path_id; + host_dev->target = stor_device->target_id; + + switch (dev_id->driver_data) { + case SFC_GUID: + host->max_lun = STORVSC_FC_MAX_LUNS_PER_TARGET; + host->max_id = STORVSC_FC_MAX_TARGETS; + host->max_channel = STORVSC_FC_MAX_CHANNELS - 1; + break; + + case SCSI_GUID: + host->max_lun = max_luns_per_target; + host->max_id = max_targets; + host->max_channel = max_channels - 1; + break; + + default: + host->max_lun = STORVSC_IDE_MAX_LUNS_PER_TARGET; + host->max_id = STORVSC_IDE_MAX_TARGETS; + host->max_channel = STORVSC_IDE_MAX_CHANNELS - 1; + break; + } + /* max cmd length */ + host->max_cmd_len = STORVSC_MAX_CMD_LEN; + + /* + * set the table size based on the info we got + * from the host. + */ + host->sg_tablesize = (stor_device->max_transfer_bytes >> PAGE_SHIFT); + + /* Register the HBA and start the scsi bus scan */ + ret = scsi_add_host(host, &device->device); + if (ret != 0) + goto err_out2; + + if (!dev_is_ide) { + scsi_scan_host(host); + } else { + target = (device->dev_instance.b[5] << 8 | + device->dev_instance.b[4]); + ret = scsi_add_device(host, 0, target, 0); + if (ret) { + scsi_remove_host(host); + goto err_out2; + } + } + return 0; + +err_out2: + /* + * Once we have connected with the host, we would need to + * to invoke storvsc_dev_remove() to rollback this state and + * this call also frees up the stor_device; hence the jump around + * err_out1 label. + */ + storvsc_dev_remove(device); + goto err_out0; + +err_out1: + kfree(stor_device); + +err_out0: + scsi_host_put(host); + return ret; +} + +static int storvsc_remove(struct hv_device *dev) +{ + struct storvsc_device *stor_device = hv_get_drvdata(dev); + struct Scsi_Host *host = stor_device->host; + + scsi_remove_host(host); + storvsc_dev_remove(dev); + scsi_host_put(host); + + return 0; +} + +static struct hv_driver storvsc_drv = { + .name = KBUILD_MODNAME, + .id_table = id_table, + .probe = storvsc_probe, + .remove = storvsc_remove, +}; + +static int __init storvsc_drv_init(void) +{ + + /* + * Divide the ring buffer data size (which is 1 page less + * than the ring buffer size since that page is reserved for + * the ring buffer indices) by the max request size (which is + * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64) + */ + max_outstanding_req_per_channel = + ((storvsc_ringbuffer_size - PAGE_SIZE) / + ALIGN(MAX_MULTIPAGE_BUFFER_PACKET + + sizeof(struct vstor_packet) + sizeof(u64) - + vmscsi_size_delta, + sizeof(u64))); + + return vmbus_driver_register(&storvsc_drv); +} + +static void __exit storvsc_drv_exit(void) +{ + vmbus_driver_unregister(&storvsc_drv); +} + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver"); +module_init(storvsc_drv_init); +module_exit(storvsc_drv_exit); |