blob: c1ba458ca79a62deabcd2fa910e4217a4a28dcb9 [file] [log] [blame]
/*
* 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>
*/
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/device.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>
#include "osd.h"
#include "logging.h"
#include "version_info.h"
#include "vmbus.h"
#include "storvsc_api.h"
struct host_device_context {
/* must be 1st field
* FIXME this is a bug */
/* point back to our device context */
struct vm_device *device_ctx;
struct kmem_cache *request_pool;
unsigned int port;
unsigned char path;
unsigned char target;
};
struct storvsc_cmd_request {
struct list_head entry;
struct scsi_cmnd *cmd;
unsigned int bounce_sgl_count;
struct scatterlist *bounce_sgl;
struct hv_storvsc_request request;
/* !!!DO NOT ADD ANYTHING BELOW HERE!!! */
/* The extension buffer falls right here and is pointed to by
* request.Extension;
* Which sounds like a very bad design... */
};
struct storvsc_driver_context {
/* !! These must be the first 2 fields !! */
/* FIXME this is a bug... */
struct driver_context drv_ctx;
struct storvsc_driver_object drv_obj;
};
/* Static decl */
static int storvsc_probe(struct device *dev);
static int storvsc_queuecommand(struct scsi_cmnd *scmnd,
void (*done)(struct scsi_cmnd *));
static int storvsc_device_alloc(struct scsi_device *);
static int storvsc_device_configure(struct scsi_device *);
static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd);
static int storvsc_remove(struct device *dev);
static struct scatterlist *create_bounce_buffer(struct scatterlist *sgl,
unsigned int sg_count,
unsigned int len);
static void destroy_bounce_buffer(struct scatterlist *sgl,
unsigned int sg_count);
static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count);
static unsigned int copy_from_bounce_buffer(struct scatterlist *orig_sgl,
struct scatterlist *bounce_sgl,
unsigned int orig_sgl_count);
static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl,
struct scatterlist *bounce_sgl,
unsigned int orig_sgl_count);
static int storvsc_get_chs(struct scsi_device *sdev, struct block_device *bdev,
sector_t capacity, int *info);
static int storvsc_ringbuffer_size = STORVSC_RING_BUFFER_SIZE;
module_param(storvsc_ringbuffer_size, int, S_IRUGO);
MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
/* The one and only one */
static struct storvsc_driver_context g_storvsc_drv;
/* Scsi driver */
static struct scsi_host_template scsi_driver = {
.module = THIS_MODULE,
.name = "storvsc_host_t",
.bios_param = storvsc_get_chs,
.queuecommand = storvsc_queuecommand,
.eh_host_reset_handler = storvsc_host_reset_handler,
.slave_alloc = storvsc_device_alloc,
.slave_configure = storvsc_device_configure,
.cmd_per_lun = 1,
/* 64 max_queue * 1 target */
.can_queue = STORVSC_MAX_IO_REQUESTS*STORVSC_MAX_TARGETS,
.this_id = -1,
/* no use setting to 0 since ll_blk_rw reset it to 1 */
/* currently 32 */
.sg_tablesize = MAX_MULTIPAGE_BUFFER_COUNT,
/*
* ENABLE_CLUSTERING allows mutiple physically contig bio_vecs to merge
* into 1 sg element. If set, we must limit the max_segment_size to
* PAGE_SIZE, otherwise we may get 1 sg element that represents
* multiple
*/
/* physically contig pfns (ie sg[x].length > PAGE_SIZE). */
.use_clustering = ENABLE_CLUSTERING,
/* Make sure we dont get a sg segment crosses a page boundary */
.dma_boundary = PAGE_SIZE-1,
};
/*
* storvsc_drv_init - StorVsc driver initialization.
*/
static int storvsc_drv_init(int (*drv_init)(struct hv_driver *drv))
{
int ret;
struct storvsc_driver_object *storvsc_drv_obj = &g_storvsc_drv.drv_obj;
struct driver_context *drv_ctx = &g_storvsc_drv.drv_ctx;
DPRINT_ENTER(STORVSC_DRV);
vmbus_get_interface(&storvsc_drv_obj->Base.VmbusChannelInterface);
storvsc_drv_obj->RingBufferSize = storvsc_ringbuffer_size;
/* Callback to client driver to complete the initialization */
drv_init(&storvsc_drv_obj->Base);
DPRINT_INFO(STORVSC_DRV,
"request extension size %u, max outstanding reqs %u",
storvsc_drv_obj->RequestExtSize,
storvsc_drv_obj->MaxOutstandingRequestsPerChannel);
if (storvsc_drv_obj->MaxOutstandingRequestsPerChannel <
STORVSC_MAX_IO_REQUESTS) {
DPRINT_ERR(STORVSC_DRV,
"The number of outstanding io requests (%d) "
"is larger than that supported (%d) internally.",
STORVSC_MAX_IO_REQUESTS,
storvsc_drv_obj->MaxOutstandingRequestsPerChannel);
return -1;
}
drv_ctx->driver.name = storvsc_drv_obj->Base.name;
memcpy(&drv_ctx->class_id, &storvsc_drv_obj->Base.deviceType,
sizeof(struct hv_guid));
drv_ctx->probe = storvsc_probe;
drv_ctx->remove = storvsc_remove;
/* The driver belongs to vmbus */
ret = vmbus_child_driver_register(drv_ctx);
DPRINT_EXIT(STORVSC_DRV);
return ret;
}
static int storvsc_drv_exit_cb(struct device *dev, void *data)
{
struct device **curr = (struct device **)data;
*curr = dev;
return 1; /* stop iterating */
}
static void storvsc_drv_exit(void)
{
struct storvsc_driver_object *storvsc_drv_obj = &g_storvsc_drv.drv_obj;
struct driver_context *drv_ctx = &g_storvsc_drv.drv_ctx;
struct device *current_dev = NULL;
int ret;
DPRINT_ENTER(STORVSC_DRV);
while (1) {
current_dev = NULL;
/* Get the device */
ret = driver_for_each_device(&drv_ctx->driver, NULL,
(void *) &current_dev,
storvsc_drv_exit_cb);
if (ret)
DPRINT_WARN(STORVSC_DRV,
"driver_for_each_device returned %d", ret);
if (current_dev == NULL)
break;
/* Initiate removal from the top-down */
device_unregister(current_dev);
}
if (storvsc_drv_obj->Base.OnCleanup)
storvsc_drv_obj->Base.OnCleanup(&storvsc_drv_obj->Base);
vmbus_child_driver_unregister(drv_ctx);
DPRINT_EXIT(STORVSC_DRV);
return;
}
/*
* storvsc_probe - Add a new device for this driver
*/
static int storvsc_probe(struct device *device)
{
int ret;
struct driver_context *driver_ctx =
driver_to_driver_context(device->driver);
struct storvsc_driver_context *storvsc_drv_ctx =
(struct storvsc_driver_context *)driver_ctx;
struct storvsc_driver_object *storvsc_drv_obj =
&storvsc_drv_ctx->drv_obj;
struct vm_device *device_ctx = device_to_vm_device(device);
struct hv_device *device_obj = &device_ctx->device_obj;
struct Scsi_Host *host;
struct host_device_context *host_device_ctx;
struct storvsc_device_info device_info;
DPRINT_ENTER(STORVSC_DRV);
if (!storvsc_drv_obj->Base.OnDeviceAdd)
return -1;
host = scsi_host_alloc(&scsi_driver,
sizeof(struct host_device_context));
if (!host) {
DPRINT_ERR(STORVSC_DRV, "unable to allocate scsi host object");
return -ENOMEM;
}
dev_set_drvdata(device, host);
host_device_ctx = (struct host_device_context *)host->hostdata;
memset(host_device_ctx, 0, sizeof(struct host_device_context));
host_device_ctx->port = host->host_no;
host_device_ctx->device_ctx = device_ctx;
host_device_ctx->request_pool =
kmem_cache_create(dev_name(&device_ctx->device),
sizeof(struct storvsc_cmd_request) +
storvsc_drv_obj->RequestExtSize, 0,
SLAB_HWCACHE_ALIGN, NULL);
if (!host_device_ctx->request_pool) {
scsi_host_put(host);
DPRINT_EXIT(STORVSC_DRV);
return -ENOMEM;
}
device_info.PortNumber = host->host_no;
/* Call to the vsc driver to add the device */
ret = storvsc_drv_obj->Base.OnDeviceAdd(device_obj,
(void *)&device_info);
if (ret != 0) {
DPRINT_ERR(STORVSC_DRV, "unable to add scsi vsc device");
kmem_cache_destroy(host_device_ctx->request_pool);
scsi_host_put(host);
DPRINT_EXIT(STORVSC_DRV);
return -1;
}
/* host_device_ctx->port = device_info.PortNumber; */
host_device_ctx->path = device_info.PathId;
host_device_ctx->target = device_info.TargetId;
/* max # of devices per target */
host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;
/* max # of targets per channel */
host->max_id = STORVSC_MAX_TARGETS;
/* max # of channels */
host->max_channel = STORVSC_MAX_CHANNELS - 1;
/* Register the HBA and start the scsi bus scan */
ret = scsi_add_host(host, device);
if (ret != 0) {
DPRINT_ERR(STORVSC_DRV, "unable to add scsi host device");
storvsc_drv_obj->Base.OnDeviceRemove(device_obj);
kmem_cache_destroy(host_device_ctx->request_pool);
scsi_host_put(host);
DPRINT_EXIT(STORVSC_DRV);
return -1;
}
scsi_scan_host(host);
DPRINT_EXIT(STORVSC_DRV);
return ret;
}
/*
* storvsc_remove - Callback when our device is removed
*/
static int storvsc_remove(struct device *device)
{
int ret;
struct driver_context *driver_ctx =
driver_to_driver_context(device->driver);
struct storvsc_driver_context *storvsc_drv_ctx =
(struct storvsc_driver_context *)driver_ctx;
struct storvsc_driver_object *storvsc_drv_obj =
&storvsc_drv_ctx->drv_obj;
struct vm_device *device_ctx = device_to_vm_device(device);
struct hv_device *device_obj = &device_ctx->device_obj;
struct Scsi_Host *host = dev_get_drvdata(device);
struct host_device_context *host_device_ctx =
(struct host_device_context *)host->hostdata;
DPRINT_ENTER(STORVSC_DRV);
if (!storvsc_drv_obj->Base.OnDeviceRemove) {
DPRINT_EXIT(STORVSC_DRV);
return -1;
}
/*
* Call to the vsc driver to let it know that the device is being
* removed
*/
ret = storvsc_drv_obj->Base.OnDeviceRemove(device_obj);
if (ret != 0) {
/* TODO: */
DPRINT_ERR(STORVSC, "unable to remove vsc device (ret %d)",
ret);
}
if (host_device_ctx->request_pool) {
kmem_cache_destroy(host_device_ctx->request_pool);
host_device_ctx->request_pool = NULL;
}
DPRINT_INFO(STORVSC, "removing host adapter (%p)...", host);
scsi_remove_host(host);
DPRINT_INFO(STORVSC, "releasing host adapter (%p)...", host);
scsi_host_put(host);
DPRINT_EXIT(STORVSC_DRV);
return ret;
}
/*
* storvsc_commmand_completion - Command completion processing
*/
static void storvsc_commmand_completion(struct hv_storvsc_request *request)
{
struct storvsc_cmd_request *cmd_request =
(struct storvsc_cmd_request *)request->Context;
struct scsi_cmnd *scmnd = cmd_request->cmd;
struct host_device_context *host_device_ctx =
(struct host_device_context *)scmnd->device->host->hostdata;
void (*scsi_done_fn)(struct scsi_cmnd *);
struct scsi_sense_hdr sense_hdr;
/* ASSERT(request == &cmd_request->request); */
/* ASSERT(scmnd); */
/* ASSERT((unsigned long)scmnd->host_scribble == */
/* (unsigned long)cmd_request); */
/* ASSERT(scmnd->scsi_done); */
DPRINT_ENTER(STORVSC_DRV);
if (cmd_request->bounce_sgl_count) {
/* using bounce buffer */
/* printk("copy_from_bounce_buffer\n"); */
/* FIXME: We can optimize on writes by just skipping this */
copy_from_bounce_buffer(scsi_sglist(scmnd),
cmd_request->bounce_sgl,
scsi_sg_count(scmnd));
destroy_bounce_buffer(cmd_request->bounce_sgl,
cmd_request->bounce_sgl_count);
}
scmnd->result = request->Status;
if (scmnd->result) {
if (scsi_normalize_sense(scmnd->sense_buffer,
request->SenseBufferSize, &sense_hdr))
scsi_print_sense_hdr("storvsc", &sense_hdr);
}
/* ASSERT(request->BytesXfer <= request->DataBuffer.Length); */
scsi_set_resid(scmnd, request->DataBuffer.Length - request->BytesXfer);
scsi_done_fn = scmnd->scsi_done;
scmnd->host_scribble = NULL;
scmnd->scsi_done = NULL;
/* !!DO NOT MODIFY the scmnd after this call */
scsi_done_fn(scmnd);
kmem_cache_free(host_device_ctx->request_pool, cmd_request);
DPRINT_EXIT(STORVSC_DRV);
}
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 i;
int num_pages;
struct scatterlist *bounce_sgl;
struct page *page_buf;
num_pages = ALIGN_UP(len, PAGE_SIZE) >> PAGE_SHIFT;
bounce_sgl = kcalloc(num_pages, sizeof(struct scatterlist), GFP_ATOMIC);
if (!bounce_sgl)
return NULL;
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, 0, 0);
}
return bounce_sgl;
cleanup:
destroy_bounce_buffer(bounce_sgl, num_pages);
return NULL;
}
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);
}
/* 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;
local_irq_save(flags);
for (i = 0; i < orig_sgl_count; i++) {
src_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])),
KM_IRQ0) + orig_sgl[i].offset;
src = src_addr;
srclen = orig_sgl[i].length;
/* ASSERT(orig_sgl[i].offset + orig_sgl[i].length <= PAGE_SIZE); */
if (bounce_addr == 0)
bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
while (srclen) {
/* assume bounce offset always == 0 */
dest = bounce_addr + bounce_sgl[j].length;
destlen = PAGE_SIZE - bounce_sgl[j].length;
copylen = min(srclen, destlen);
memcpy((void *)dest, (void *)src, copylen);
total_copied += copylen;
bounce_sgl[j].length += copylen;
srclen -= copylen;
src += copylen;
if (bounce_sgl[j].length == PAGE_SIZE) {
/* full..move to next entry */
kunmap_atomic((void *)bounce_addr, KM_IRQ0);
j++;
/* if we need to use another bounce buffer */
if (srclen || i != orig_sgl_count - 1)
bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
} else if (srclen == 0 && i == orig_sgl_count - 1) {
/* unmap the last bounce that is < PAGE_SIZE */
kunmap_atomic((void *)bounce_addr, KM_IRQ0);
}
}
kunmap_atomic((void *)(src_addr - orig_sgl[i].offset), KM_IRQ0);
}
local_irq_restore(flags);
return total_copied;
}
/* 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)
{
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;
local_irq_save(flags);
for (i = 0; i < orig_sgl_count; i++) {
dest_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])),
KM_IRQ0) + orig_sgl[i].offset;
dest = dest_addr;
destlen = orig_sgl[i].length;
/* ASSERT(orig_sgl[i].offset + orig_sgl[i].length <= PAGE_SIZE); */
if (bounce_addr == 0)
bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
while (destlen) {
src = bounce_addr + bounce_sgl[j].offset;
srclen = bounce_sgl[j].length - bounce_sgl[j].offset;
copylen = min(srclen, destlen);
memcpy((void *)dest, (void *)src, copylen);
total_copied += copylen;
bounce_sgl[j].offset += copylen;
destlen -= copylen;
dest += copylen;
if (bounce_sgl[j].offset == bounce_sgl[j].length) {
/* full */
kunmap_atomic((void *)bounce_addr, KM_IRQ0);
j++;
/* if we need to use another bounce buffer */
if (destlen || i != orig_sgl_count - 1)
bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
} else if (destlen == 0 && i == orig_sgl_count - 1) {
/* unmap the last bounce that is < PAGE_SIZE */
kunmap_atomic((void *)bounce_addr, KM_IRQ0);
}
}
kunmap_atomic((void *)(dest_addr - orig_sgl[i].offset),
KM_IRQ0);
}
local_irq_restore(flags);
return total_copied;
}
/*
* storvsc_queuecommand - Initiate command processing
*/
static int storvsc_queuecommand(struct scsi_cmnd *scmnd,
void (*done)(struct scsi_cmnd *))
{
int ret;
struct host_device_context *host_device_ctx =
(struct host_device_context *)scmnd->device->host->hostdata;
struct vm_device *device_ctx = host_device_ctx->device_ctx;
struct driver_context *driver_ctx =
driver_to_driver_context(device_ctx->device.driver);
struct storvsc_driver_context *storvsc_drv_ctx =
(struct storvsc_driver_context *)driver_ctx;
struct storvsc_driver_object *storvsc_drv_obj =
&storvsc_drv_ctx->drv_obj;
struct hv_storvsc_request *request;
struct storvsc_cmd_request *cmd_request;
unsigned int request_size = 0;
int i;
struct scatterlist *sgl;
unsigned int sg_count = 0;
DPRINT_ENTER(STORVSC_DRV);
DPRINT_DBG(STORVSC_DRV, "scmnd %p dir %d, use_sg %d buf %p len %d "
"queue depth %d tagged %d", scmnd, scmnd->sc_data_direction,
scsi_sg_count(scmnd), scsi_sglist(scmnd),
scsi_bufflen(scmnd), scmnd->device->queue_depth,
scmnd->device->tagged_supported);
/* If retrying, no need to prep the cmd */
if (scmnd->host_scribble) {
/* ASSERT(scmnd->scsi_done != NULL); */
cmd_request =
(struct storvsc_cmd_request *)scmnd->host_scribble;
DPRINT_INFO(STORVSC_DRV, "retrying scmnd %p cmd_request %p",
scmnd, cmd_request);
goto retry_request;
}
/* ASSERT(scmnd->scsi_done == NULL); */
/* ASSERT(scmnd->host_scribble == NULL); */
scmnd->scsi_done = done;
request_size = sizeof(struct storvsc_cmd_request);
cmd_request = kmem_cache_alloc(host_device_ctx->request_pool,
GFP_ATOMIC);
if (!cmd_request) {
DPRINT_ERR(STORVSC_DRV, "scmnd (%p) - unable to allocate "
"storvsc_cmd_request...marking queue busy", scmnd);
scmnd->scsi_done = NULL;
return SCSI_MLQUEUE_DEVICE_BUSY;
}
/* Setup the cmd request */
cmd_request->bounce_sgl_count = 0;
cmd_request->bounce_sgl = NULL;
cmd_request->cmd = scmnd;
scmnd->host_scribble = (unsigned char *)cmd_request;
request = &cmd_request->request;
request->Extension =
(void *)((unsigned long)cmd_request + request_size);
DPRINT_DBG(STORVSC_DRV, "req %p size %d ext %d", request, request_size,
storvsc_drv_obj->RequestExtSize);
/* Build the SRB */
switch (scmnd->sc_data_direction) {
case DMA_TO_DEVICE:
request->Type = WRITE_TYPE;
break;
case DMA_FROM_DEVICE:
request->Type = READ_TYPE;
break;
default:
request->Type = UNKNOWN_TYPE;
break;
}
request->OnIOCompletion = storvsc_commmand_completion;
request->Context = cmd_request;/* scmnd; */
/* request->PortId = scmnd->device->channel; */
request->Host = host_device_ctx->port;
request->Bus = scmnd->device->channel;
request->TargetId = scmnd->device->id;
request->LunId = scmnd->device->lun;
/* ASSERT(scmnd->cmd_len <= 16); */
request->CdbLen = scmnd->cmd_len;
request->Cdb = scmnd->cmnd;
request->SenseBuffer = scmnd->sense_buffer;
request->SenseBufferSize = SCSI_SENSE_BUFFERSIZE;
request->DataBuffer.Length = scsi_bufflen(scmnd);
if (scsi_sg_count(scmnd)) {
sgl = (struct scatterlist *)scsi_sglist(scmnd);
sg_count = scsi_sg_count(scmnd);
/* check if we need to bounce the sgl */
if (do_bounce_buffer(sgl, scsi_sg_count(scmnd)) != -1) {
DPRINT_INFO(STORVSC_DRV,
"need to bounce buffer for this scmnd %p",
scmnd);
cmd_request->bounce_sgl =
create_bounce_buffer(sgl, scsi_sg_count(scmnd),
scsi_bufflen(scmnd));
if (!cmd_request->bounce_sgl) {
DPRINT_ERR(STORVSC_DRV,
"unable to create bounce buffer for "
"this scmnd %p", scmnd);
scmnd->scsi_done = NULL;
scmnd->host_scribble = NULL;
kmem_cache_free(host_device_ctx->request_pool,
cmd_request);
return SCSI_MLQUEUE_HOST_BUSY;
}
cmd_request->bounce_sgl_count =
ALIGN_UP(scsi_bufflen(scmnd), PAGE_SIZE) >>
PAGE_SHIFT;
/*
* FIXME: We can optimize on reads by just skipping
* this
*/
copy_to_bounce_buffer(sgl, cmd_request->bounce_sgl,
scsi_sg_count(scmnd));
sgl = cmd_request->bounce_sgl;
sg_count = cmd_request->bounce_sgl_count;
}
request->DataBuffer.Offset = sgl[0].offset;
for (i = 0; i < sg_count; i++) {
DPRINT_DBG(STORVSC_DRV, "sgl[%d] len %d offset %d\n",
i, sgl[i].length, sgl[i].offset);
request->DataBuffer.PfnArray[i] =
page_to_pfn(sg_page((&sgl[i])));
}
} else if (scsi_sglist(scmnd)) {
/* ASSERT(scsi_bufflen(scmnd) <= PAGE_SIZE); */
request->DataBuffer.Offset =
virt_to_phys(scsi_sglist(scmnd)) & (PAGE_SIZE-1);
request->DataBuffer.PfnArray[0] =
virt_to_phys(scsi_sglist(scmnd)) >> PAGE_SHIFT;
}
retry_request:
/* Invokes the vsc to start an IO */
ret = storvsc_drv_obj->OnIORequest(&device_ctx->device_obj,
&cmd_request->request);
if (ret == -1) {
/* no more space */
DPRINT_ERR(STORVSC_DRV,
"scmnd (%p) - queue FULL...marking queue busy",
scmnd);
if (cmd_request->bounce_sgl_count) {
/*
* FIXME: We can optimize on writes by just skipping
* this
*/
copy_from_bounce_buffer(scsi_sglist(scmnd),
cmd_request->bounce_sgl,
scsi_sg_count(scmnd));
destroy_bounce_buffer(cmd_request->bounce_sgl,
cmd_request->bounce_sgl_count);
}
kmem_cache_free(host_device_ctx->request_pool, cmd_request);
scmnd->scsi_done = NULL;
scmnd->host_scribble = NULL;
ret = SCSI_MLQUEUE_DEVICE_BUSY;
}
DPRINT_EXIT(STORVSC_DRV);
return ret;
}
static int storvsc_merge_bvec(struct request_queue *q,
struct bvec_merge_data *bmd, struct bio_vec *bvec)
{
/* checking done by caller. */
return bvec->bv_len;
}
/*
* storvsc_device_configure - Configure the specified scsi device
*/
static int storvsc_device_alloc(struct scsi_device *sdevice)
{
DPRINT_DBG(STORVSC_DRV, "sdev (%p) - setting device flag to %d",
sdevice, BLIST_SPARSELUN);
/*
* This enables luns to be located sparsely. Otherwise, we may not
* discovered them.
*/
sdevice->sdev_bflags |= BLIST_SPARSELUN | BLIST_LARGELUN;
return 0;
}
static int storvsc_device_configure(struct scsi_device *sdevice)
{
DPRINT_INFO(STORVSC_DRV, "sdev (%p) - curr queue depth %d", sdevice,
sdevice->queue_depth);
DPRINT_INFO(STORVSC_DRV, "sdev (%p) - setting queue depth to %d",
sdevice, STORVSC_MAX_IO_REQUESTS);
scsi_adjust_queue_depth(sdevice, MSG_SIMPLE_TAG,
STORVSC_MAX_IO_REQUESTS);
DPRINT_INFO(STORVSC_DRV, "sdev (%p) - setting max segment size to %ld",
sdevice, PAGE_SIZE);
blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE);
DPRINT_INFO(STORVSC_DRV, "sdev (%p) - adding merge bio vec routine",
sdevice);
blk_queue_merge_bvec(sdevice->request_queue, storvsc_merge_bvec);
blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY);
/* sdevice->timeout = (2000 * HZ);//(75 * HZ); */
return 0;
}
/*
* storvsc_host_reset_handler - Reset the scsi HBA
*/
static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
{
int ret;
struct host_device_context *host_device_ctx =
(struct host_device_context *)scmnd->device->host->hostdata;
struct vm_device *device_ctx = host_device_ctx->device_ctx;
DPRINT_ENTER(STORVSC_DRV);
DPRINT_INFO(STORVSC_DRV, "sdev (%p) dev obj (%p) - host resetting...",
scmnd->device, &device_ctx->device_obj);
/* Invokes the vsc to reset the host/bus */
ret = StorVscOnHostReset(&device_ctx->device_obj);
if (ret != 0) {
DPRINT_EXIT(STORVSC_DRV);
return ret;
}
DPRINT_INFO(STORVSC_DRV, "sdev (%p) dev obj (%p) - host reseted",
scmnd->device, &device_ctx->device_obj);
DPRINT_EXIT(STORVSC_DRV);
return ret;
}
static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
sector_t capacity, int *info)
{
sector_t total_sectors = capacity;
sector_t cylinder_times_heads = 0;
sector_t temp = 0;
int sectors_per_track = 0;
int heads = 0;
int cylinders = 0;
int rem = 0;
if (total_sectors > (65535 * 16 * 255))
total_sectors = (65535 * 16 * 255);
if (total_sectors >= (65535 * 16 * 63)) {
sectors_per_track = 255;
heads = 16;
cylinder_times_heads = total_sectors;
/* sector_div stores the quotient in cylinder_times_heads */
rem = sector_div(cylinder_times_heads, sectors_per_track);
} else {
sectors_per_track = 17;
cylinder_times_heads = total_sectors;
/* sector_div stores the quotient in cylinder_times_heads */
rem = sector_div(cylinder_times_heads, sectors_per_track);
temp = cylinder_times_heads + 1023;
/* sector_div stores the quotient in temp */
rem = sector_div(temp, 1024);
heads = temp;
if (heads < 4)
heads = 4;
if (cylinder_times_heads >= (heads * 1024) || (heads > 16)) {
sectors_per_track = 31;
heads = 16;
cylinder_times_heads = total_sectors;
/*
* sector_div stores the quotient in
* cylinder_times_heads
*/
rem = sector_div(cylinder_times_heads,
sectors_per_track);
}
if (cylinder_times_heads >= (heads * 1024)) {
sectors_per_track = 63;
heads = 16;
cylinder_times_heads = total_sectors;
/*
* sector_div stores the quotient in
* cylinder_times_heads
*/
rem = sector_div(cylinder_times_heads,
sectors_per_track);
}
}
temp = cylinder_times_heads;
/* sector_div stores the quotient in temp */
rem = sector_div(temp, heads);
cylinders = temp;
info[0] = heads;
info[1] = sectors_per_track;
info[2] = cylinders;
DPRINT_INFO(STORVSC_DRV, "CHS (%d, %d, %d)", cylinders, heads,
sectors_per_track);
return 0;
}
static int __init storvsc_init(void)
{
int ret;
DPRINT_ENTER(STORVSC_DRV);
DPRINT_INFO(STORVSC_DRV, "Storvsc initializing....");
ret = storvsc_drv_init(StorVscInitialize);
DPRINT_EXIT(STORVSC_DRV);
return ret;
}
static void __exit storvsc_exit(void)
{
DPRINT_ENTER(STORVSC_DRV);
storvsc_drv_exit();
DPRINT_ENTER(STORVSC_DRV);
}
MODULE_LICENSE("GPL");
MODULE_VERSION(HV_DRV_VERSION);
MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
module_init(storvsc_init);
module_exit(storvsc_exit);