/*
* 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);