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/*
* 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>
*
* 4/3/2011: K. Y. Srinivasan - Significant restructuring and cleanup.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/blkdev.h>
#include <linux/major.h>
#include <linux/delay.h>
#include <linux/hdreg.h>
#include <linux/slab.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_dbg.h>
#include "hv_api.h"
#include "logging.h"
#include "version_info.h"
#include "vmbus.h"
#include "storvsc_api.h"
#define BLKVSC_MINORS 64
enum blkvsc_device_type {
UNKNOWN_DEV_TYPE,
HARDDISK_TYPE,
DVD_TYPE,
};
enum blkvsc_op_type {
DO_INQUIRY,
DO_CAPACITY,
DO_FLUSH,
};
/*
* This request ties the struct request and struct
* blkvsc_request/hv_storvsc_request together A struct request may be
* represented by 1 or more struct blkvsc_request
*/
struct blkvsc_request_group {
int outstanding;
int status;
struct list_head blkvsc_req_list; /* list of blkvsc_requests */
};
struct blkvsc_request {
/* blkvsc_request_group.blkvsc_req_list */
struct list_head req_entry;
/* block_device_context.pending_list */
struct list_head pend_entry;
/* This may be null if we generate a request internally */
struct request *req;
struct block_device_context *dev;
/* The group this request is part of. Maybe null */
struct blkvsc_request_group *group;
int write;
sector_t sector_start;
unsigned long sector_count;
unsigned char sense_buffer[SCSI_SENSE_BUFFERSIZE];
unsigned char cmd_len;
unsigned char cmnd[MAX_COMMAND_SIZE];
struct hv_storvsc_request request;
};
/* Per device structure */
struct block_device_context {
/* point back to our device context */
struct hv_device *device_ctx;
struct kmem_cache *request_pool;
spinlock_t lock;
struct gendisk *gd;
enum blkvsc_device_type device_type;
struct list_head pending_list;
unsigned char device_id[64];
unsigned int device_id_len;
int num_outstanding_reqs;
int shutting_down;
unsigned int sector_size;
sector_t capacity;
unsigned int port;
unsigned char path;
unsigned char target;
int users;
};
static const char *drv_name = "blkvsc";
/* {32412632-86cb-44a2-9b5c-50d1417354f5} */
static const struct hv_guid dev_type = {
.data = {
0x32, 0x26, 0x41, 0x32, 0xcb, 0x86, 0xa2, 0x44,
0x9b, 0x5c, 0x50, 0xd1, 0x41, 0x73, 0x54, 0xf5
}
};
/*
* There is a circular dependency involving blkvsc_request_completion()
* and blkvsc_do_request().
*/
static void blkvsc_request_completion(struct hv_storvsc_request *request);
static int blkvsc_ringbuffer_size = BLKVSC_RING_BUFFER_SIZE;
module_param(blkvsc_ringbuffer_size, int, S_IRUGO);
MODULE_PARM_DESC(ring_size, "Ring buffer size (in bytes)");
/*
* There is a circular dependency involving blkvsc_probe()
* and block_ops.
*/
static int blkvsc_probe(struct hv_device *dev);
static int blkvsc_device_add(struct hv_device *device,
void *additional_info)
{
struct storvsc_device_info *device_info;
int ret = 0;
device_info = (struct storvsc_device_info *)additional_info;
ret = storvsc_dev_add(device, additional_info);
if (ret != 0)
return ret;
/*
* We need to use the device instance guid to set the path and target
* id. For IDE devices, the device instance id is formatted as
* <bus id> * - <device id> - 8899 - 000000000000.
*/
device_info->path_id = device->dev_instance.data[3] << 24 |
device->dev_instance.data[2] << 16 |
device->dev_instance.data[1] << 8 |
device->dev_instance.data[0];
device_info->target_id = device->dev_instance.data[5] << 8 |
device->dev_instance.data[4];
return ret;
}
static int blk_vsc_initialize(struct hv_driver *driver)
{
struct storvsc_driver *stor_driver;
int ret = 0;
stor_driver = hvdr_to_stordr(driver);
/* Make sure we are at least 2 pages since 1 page is used for control */
driver->name = drv_name;
memcpy(&driver->dev_type, &dev_type, sizeof(struct hv_guid));
/*
* 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)
*/
stor_driver->max_outstanding_req_per_channel =
((stor_driver->ring_buffer_size - PAGE_SIZE) /
ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
sizeof(struct vstor_packet) + sizeof(u64),
sizeof(u64)));
DPRINT_INFO(BLKVSC, "max io outstd %u",
stor_driver->max_outstanding_req_per_channel);
/* Setup the dispatch table */
stor_driver->base.dev_rm = storvsc_dev_remove;
stor_driver->base.cleanup = stor_vsc_on_cleanup;
stor_driver->on_io_request = stor_vsc_on_io_request;
return ret;
}
static int blkvsc_submit_request(struct blkvsc_request *blkvsc_req,
void (*request_completion)(struct hv_storvsc_request *))
{
struct block_device_context *blkdev = blkvsc_req->dev;
struct hv_device *device_ctx = blkdev->device_ctx;
struct storvsc_driver *storvsc_drv =
drv_to_stordrv(device_ctx->device.driver);
struct hv_storvsc_request *storvsc_req;
struct vmscsi_request *vm_srb;
int ret;
storvsc_req = &blkvsc_req->request;
vm_srb = &storvsc_req->vstor_packet.vm_srb;
vm_srb->data_in = blkvsc_req->write ? WRITE_TYPE : READ_TYPE;
storvsc_req->on_io_completion = request_completion;
storvsc_req->context = blkvsc_req;
vm_srb->port_number = blkdev->port;
vm_srb->path_id = blkdev->path;
vm_srb->target_id = blkdev->target;
vm_srb->lun = 0; /* this is not really used at all */
vm_srb->cdb_length = blkvsc_req->cmd_len;
memcpy(vm_srb->cdb, blkvsc_req->cmnd, vm_srb->cdb_length);
storvsc_req->sense_buffer = blkvsc_req->sense_buffer;
ret = storvsc_drv->on_io_request(blkdev->device_ctx,
&blkvsc_req->request);
if (ret == 0)
blkdev->num_outstanding_reqs++;
return ret;
}
static int blkvsc_open(struct block_device *bdev, fmode_t mode)
{
struct block_device_context *blkdev = bdev->bd_disk->private_data;
unsigned long flags;
spin_lock_irqsave(&blkdev->lock, flags);
blkdev->users++;
spin_unlock_irqrestore(&blkdev->lock, flags);
return 0;
}
static int blkvsc_getgeo(struct block_device *bd, struct hd_geometry *hg)
{
sector_t nsect = get_capacity(bd->bd_disk);
sector_t cylinders = nsect;
/*
* We are making up these values; let us keep it simple.
*/
hg->heads = 0xff;
hg->sectors = 0x3f;
sector_div(cylinders, hg->heads * hg->sectors);
hg->cylinders = cylinders;
if ((sector_t)(hg->cylinders + 1) * hg->heads * hg->sectors < nsect)
hg->cylinders = 0xffff;
return 0;
}
static void blkvsc_init_rw(struct blkvsc_request *blkvsc_req)
{
blkvsc_req->cmd_len = 16;
if (rq_data_dir(blkvsc_req->req)) {
blkvsc_req->write = 1;
blkvsc_req->cmnd[0] = WRITE_16;
} else {
blkvsc_req->write = 0;
blkvsc_req->cmnd[0] = READ_16;
}
blkvsc_req->cmnd[1] |=
(blkvsc_req->req->cmd_flags & REQ_FUA) ? 0x8 : 0;
*(unsigned long long *)&blkvsc_req->cmnd[2] =
cpu_to_be64(blkvsc_req->sector_start);
*(unsigned int *)&blkvsc_req->cmnd[10] =
cpu_to_be32(blkvsc_req->sector_count);
}
static int blkvsc_ioctl(struct block_device *bd, fmode_t mode,
unsigned cmd, unsigned long arg)
{
struct block_device_context *blkdev = bd->bd_disk->private_data;
int ret = 0;
switch (cmd) {
case HDIO_GET_IDENTITY:
if (copy_to_user((void __user *)arg, blkdev->device_id,
blkdev->device_id_len))
ret = -EFAULT;
break;
default:
ret = -EINVAL;
break;
}
return ret;
}
static void blkvsc_cmd_completion(struct hv_storvsc_request *request)
{
struct blkvsc_request *blkvsc_req =
(struct blkvsc_request *)request->context;
struct block_device_context *blkdev =
(struct block_device_context *)blkvsc_req->dev;
struct scsi_sense_hdr sense_hdr;
struct vmscsi_request *vm_srb;
unsigned long flags;
vm_srb = &blkvsc_req->request.vstor_packet.vm_srb;
spin_lock_irqsave(&blkdev->lock, flags);
blkdev->num_outstanding_reqs--;
spin_unlock_irqrestore(&blkdev->lock, flags);
if (vm_srb->scsi_status)
if (scsi_normalize_sense(blkvsc_req->sense_buffer,
SCSI_SENSE_BUFFERSIZE, &sense_hdr))
scsi_print_sense_hdr("blkvsc", &sense_hdr);
complete(&blkvsc_req->request.wait_event);
}
static int blkvsc_do_operation(struct block_device_context *blkdev,
enum blkvsc_op_type op)
{
struct blkvsc_request *blkvsc_req;
struct page *page_buf;
unsigned char *buf;
unsigned char device_type;
struct scsi_sense_hdr sense_hdr;
struct vmscsi_request *vm_srb;
unsigned long flags;
int ret = 0;
blkvsc_req = kmem_cache_zalloc(blkdev->request_pool, GFP_KERNEL);
if (!blkvsc_req)
return -ENOMEM;
page_buf = alloc_page(GFP_KERNEL);
if (!page_buf) {
kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
return -ENOMEM;
}
vm_srb = &blkvsc_req->request.vstor_packet.vm_srb;
init_completion(&blkvsc_req->request.wait_event);
blkvsc_req->dev = blkdev;
blkvsc_req->req = NULL;
blkvsc_req->write = 0;
blkvsc_req->request.data_buffer.pfn_array[0] =
page_to_pfn(page_buf);
blkvsc_req->request.data_buffer.offset = 0;
switch (op) {
case DO_INQUIRY:
blkvsc_req->cmnd[0] = INQUIRY;
blkvsc_req->cmnd[1] = 0x1; /* Get product data */
blkvsc_req->cmnd[2] = 0x83; /* mode page 83 */
blkvsc_req->cmnd[4] = 64;
blkvsc_req->cmd_len = 6;
blkvsc_req->request.data_buffer.len = 64;
break;
case DO_CAPACITY:
blkdev->sector_size = 0;
blkdev->capacity = 0;
blkvsc_req->cmnd[0] = READ_CAPACITY;
blkvsc_req->cmd_len = 16;
blkvsc_req->request.data_buffer.len = 8;
break;
case DO_FLUSH:
blkvsc_req->cmnd[0] = SYNCHRONIZE_CACHE;
blkvsc_req->cmd_len = 10;
blkvsc_req->request.data_buffer.pfn_array[0] = 0;
blkvsc_req->request.data_buffer.len = 0;
break;
default:
ret = -EINVAL;
goto cleanup;
}
spin_lock_irqsave(&blkdev->lock, flags);
blkvsc_submit_request(blkvsc_req, blkvsc_cmd_completion);
spin_unlock_irqrestore(&blkdev->lock, flags);
wait_for_completion_interruptible(&blkvsc_req->request.wait_event);
/* check error */
if (vm_srb->scsi_status) {
scsi_normalize_sense(blkvsc_req->sense_buffer,
SCSI_SENSE_BUFFERSIZE, &sense_hdr);
return 0;
}
buf = kmap(page_buf);
switch (op) {
case DO_INQUIRY:
device_type = buf[0] & 0x1F;
if (device_type == 0x0)
blkdev->device_type = HARDDISK_TYPE;
else
blkdev->device_type = UNKNOWN_DEV_TYPE;
blkdev->device_id_len = buf[7];
if (blkdev->device_id_len > 64)
blkdev->device_id_len = 64;
memcpy(blkdev->device_id, &buf[8], blkdev->device_id_len);
break;
case DO_CAPACITY:
/* be to le */
blkdev->capacity =
((buf[0] << 24) | (buf[1] << 16) |
(buf[2] << 8) | buf[3]) + 1;
blkdev->sector_size =
(buf[4] << 24) | (buf[5] << 16) |
(buf[6] << 8) | buf[7];
break;
default:
break;
}
cleanup:
kunmap(page_buf);
__free_page(page_buf);
kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
return ret;
}
static int blkvsc_cancel_pending_reqs(struct block_device_context *blkdev)
{
struct blkvsc_request *pend_req, *tmp;
struct blkvsc_request *comp_req, *tmp2;
struct vmscsi_request *vm_srb;
int ret = 0;
/* Flush the pending list first */
list_for_each_entry_safe(pend_req, tmp, &blkdev->pending_list,
pend_entry) {
/*
* The pend_req could be part of a partially completed
* request. If so, complete those req first until we
* hit the pend_req
*/
list_for_each_entry_safe(comp_req, tmp2,
&pend_req->group->blkvsc_req_list,
req_entry) {
if (comp_req == pend_req)
break;
list_del(&comp_req->req_entry);
if (comp_req->req) {
vm_srb =
&comp_req->request.vstor_packet.
vm_srb;
ret = __blk_end_request(comp_req->req,
(!vm_srb->scsi_status ? 0 : -EIO),
comp_req->sector_count *
blkdev->sector_size);
/* FIXME: shouldn't this do more than return? */
if (ret)
goto out;
}
kmem_cache_free(blkdev->request_pool, comp_req);
}
list_del(&pend_req->pend_entry);
list_del(&pend_req->req_entry);
if (comp_req->req) {
if (!__blk_end_request(pend_req->req, -EIO,
pend_req->sector_count *
blkdev->sector_size)) {
/*
* All the sectors have been xferred ie the
* request is done
*/
kmem_cache_free(blkdev->request_pool,
pend_req->group);
}
}
kmem_cache_free(blkdev->request_pool, pend_req);
}
out:
return ret;
}
/*
* blkvsc_remove() - Callback when our device is removed
*/
static int blkvsc_remove(struct hv_device *dev)
{
struct storvsc_driver *storvsc_drv =
drv_to_stordrv(dev->device.driver);
struct block_device_context *blkdev = dev_get_drvdata(&dev->device);
unsigned long flags;
/*
* Call to the vsc driver to let it know that the device is being
* removed
*/
storvsc_drv->base.dev_rm(dev);
/* Get to a known state */
spin_lock_irqsave(&blkdev->lock, flags);
blkdev->shutting_down = 1;
blk_stop_queue(blkdev->gd->queue);
blkvsc_cancel_pending_reqs(blkdev);
spin_unlock_irqrestore(&blkdev->lock, flags);
while (blkdev->num_outstanding_reqs) {
DPRINT_INFO(STORVSC, "waiting for %d requests to complete...",
blkdev->num_outstanding_reqs);
udelay(100);
}
blkvsc_do_operation(blkdev, DO_FLUSH);
blk_cleanup_queue(blkdev->gd->queue);
del_gendisk(blkdev->gd);
kmem_cache_destroy(blkdev->request_pool);
kfree(blkdev);
return 0;
}
static void blkvsc_shutdown(struct hv_device *dev)
{
struct block_device_context *blkdev = dev_get_drvdata(&dev->device);
unsigned long flags;
if (!blkdev)
return;
spin_lock_irqsave(&blkdev->lock, flags);
blkdev->shutting_down = 1;
blk_stop_queue(blkdev->gd->queue);
blkvsc_cancel_pending_reqs(blkdev);
spin_unlock_irqrestore(&blkdev->lock, flags);
while (blkdev->num_outstanding_reqs) {
DPRINT_INFO(STORVSC, "waiting for %d requests to complete...",
blkdev->num_outstanding_reqs);
udelay(100);
}
blkvsc_do_operation(blkdev, DO_FLUSH);
}
static int blkvsc_release(struct gendisk *disk, fmode_t mode)
{
struct block_device_context *blkdev = disk->private_data;
unsigned long flags;
if (blkdev->users == 1) {
blkvsc_do_operation(blkdev, DO_FLUSH);
}
spin_lock_irqsave(&blkdev->lock, flags);
blkdev->users--;
spin_unlock_irqrestore(&blkdev->lock, flags);
return 0;
}
/*
* We break the request into 1 or more blkvsc_requests and submit
* them. If we cant submit them all, we put them on the
* pending_list. The blkvsc_request() will work on the pending_list.
*/
static int blkvsc_do_request(struct block_device_context *blkdev,
struct request *req)
{
struct bio *bio = NULL;
struct bio_vec *bvec = NULL;
struct bio_vec *prev_bvec = NULL;
struct blkvsc_request *blkvsc_req = NULL;
struct blkvsc_request *tmp;
int databuf_idx = 0;
int seg_idx = 0;
sector_t start_sector;
unsigned long num_sectors = 0;
int ret = 0;
int pending = 0;
struct blkvsc_request_group *group = NULL;
/* Create a group to tie req to list of blkvsc_reqs */
group = kmem_cache_zalloc(blkdev->request_pool, GFP_ATOMIC);
if (!group)
return -ENOMEM;
INIT_LIST_HEAD(&group->blkvsc_req_list);
group->outstanding = group->status = 0;
start_sector = blk_rq_pos(req);
/* foreach bio in the request */
if (req->bio) {
for (bio = req->bio; bio; bio = bio->bi_next) {
/*
* Map this bio into an existing or new storvsc request
*/
bio_for_each_segment(bvec, bio, seg_idx) {
/* Get a new storvsc request */
/* 1st-time */
if ((!blkvsc_req) ||
(databuf_idx >= MAX_MULTIPAGE_BUFFER_COUNT)
/* hole at the begin of page */
|| (bvec->bv_offset != 0) ||
/* hold at the end of page */
(prev_bvec &&
(prev_bvec->bv_len != PAGE_SIZE))) {
/* submit the prev one */
if (blkvsc_req) {
blkvsc_req->sector_start =
start_sector;
sector_div(
blkvsc_req->sector_start,
(blkdev->sector_size >> 9));
blkvsc_req->sector_count =
num_sectors /
(blkdev->sector_size >> 9);
blkvsc_init_rw(blkvsc_req);
}
/*
* Create new blkvsc_req to represent
* the current bvec
*/
blkvsc_req =
kmem_cache_zalloc(
blkdev->request_pool, GFP_ATOMIC);
if (!blkvsc_req) {
/* free up everything */
list_for_each_entry_safe(
blkvsc_req, tmp,
&group->blkvsc_req_list,
req_entry) {
list_del(
&blkvsc_req->req_entry);
kmem_cache_free(
blkdev->request_pool,
blkvsc_req);
}
kmem_cache_free(
blkdev->request_pool, group);
return -ENOMEM;
}
memset(blkvsc_req, 0,
sizeof(struct blkvsc_request));
blkvsc_req->dev = blkdev;
blkvsc_req->req = req;
blkvsc_req->request.
data_buffer.offset
= bvec->bv_offset;
blkvsc_req->request.
data_buffer.len = 0;
/* Add to the group */
blkvsc_req->group = group;
blkvsc_req->group->outstanding++;
list_add_tail(&blkvsc_req->req_entry,
&blkvsc_req->group->blkvsc_req_list);
start_sector += num_sectors;
num_sectors = 0;
databuf_idx = 0;
}
/*
* Add the curr bvec/segment to the curr
* blkvsc_req
*/
blkvsc_req->request.data_buffer.
pfn_array[databuf_idx]
= page_to_pfn(bvec->bv_page);
blkvsc_req->request.data_buffer.len
+= bvec->bv_len;
prev_bvec = bvec;
databuf_idx++;
num_sectors += bvec->bv_len >> 9;
} /* bio_for_each_segment */
} /* rq_for_each_bio */
}
/* Handle the last one */
if (blkvsc_req) {
blkvsc_req->sector_start = start_sector;
sector_div(blkvsc_req->sector_start,
(blkdev->sector_size >> 9));
blkvsc_req->sector_count = num_sectors /
(blkdev->sector_size >> 9);
blkvsc_init_rw(blkvsc_req);
}
list_for_each_entry(blkvsc_req, &group->blkvsc_req_list, req_entry) {
if (pending) {
list_add_tail(&blkvsc_req->pend_entry,
&blkdev->pending_list);
} else {
ret = blkvsc_submit_request(blkvsc_req,
blkvsc_request_completion);
if (ret == -1) {
pending = 1;
list_add_tail(&blkvsc_req->pend_entry,
&blkdev->pending_list);
}
}
}
return pending;
}
static int blkvsc_do_pending_reqs(struct block_device_context *blkdev)
{
struct blkvsc_request *pend_req, *tmp;
int ret = 0;
/* Flush the pending list first */
list_for_each_entry_safe(pend_req, tmp, &blkdev->pending_list,
pend_entry) {
ret = blkvsc_submit_request(pend_req,
blkvsc_request_completion);
if (ret != 0)
break;
else
list_del(&pend_req->pend_entry);
}
return ret;
}
static void blkvsc_request(struct request_queue *queue)
{
struct block_device_context *blkdev = NULL;
struct request *req;
int ret = 0;
while ((req = blk_peek_request(queue)) != NULL) {
blkdev = req->rq_disk->private_data;
if (blkdev->shutting_down || req->cmd_type != REQ_TYPE_FS) {
__blk_end_request_cur(req, 0);
continue;
}
ret = blkvsc_do_pending_reqs(blkdev);
if (ret != 0) {
blk_stop_queue(queue);
break;
}
blk_start_request(req);
ret = blkvsc_do_request(blkdev, req);
if (ret > 0) {
blk_stop_queue(queue);
break;
} else if (ret < 0) {
blk_requeue_request(queue, req);
blk_stop_queue(queue);
break;
}
}
}
/* The one and only one */
static struct storvsc_driver blkvsc_drv;
static const struct block_device_operations block_ops = {
.owner = THIS_MODULE,
.open = blkvsc_open,
.release = blkvsc_release,
.getgeo = blkvsc_getgeo,
.ioctl = blkvsc_ioctl,
};
/*
* blkvsc_drv_init - BlkVsc driver initialization.
*/
static int blkvsc_drv_init(void)
{
struct storvsc_driver *storvsc_drv = &blkvsc_drv;
struct hv_driver *drv = &blkvsc_drv.base;
int ret;
storvsc_drv->ring_buffer_size = blkvsc_ringbuffer_size;
/* Callback to client driver to complete the initialization */
blk_vsc_initialize(&storvsc_drv->base);
drv->driver.name = storvsc_drv->base.name;
drv->probe = blkvsc_probe;
drv->remove = blkvsc_remove;
drv->shutdown = blkvsc_shutdown;
/* The driver belongs to vmbus */
ret = vmbus_child_driver_register(&drv->driver);
return ret;
}
static int blkvsc_drv_exit_cb(struct device *dev, void *data)
{
struct device **curr = (struct device **)data;
*curr = dev;
return 1; /* stop iterating */
}
static void blkvsc_drv_exit(void)
{
struct storvsc_driver *storvsc_drv = &blkvsc_drv;
struct hv_driver *drv = &blkvsc_drv.base;
struct device *current_dev;
int ret;
while (1) {
current_dev = NULL;
/* Get the device */
ret = driver_for_each_device(&drv->driver, NULL,
(void *) ¤t_dev,
blkvsc_drv_exit_cb);
if (ret)
DPRINT_WARN(BLKVSC_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->base.cleanup)
storvsc_drv->base.cleanup(&storvsc_drv->base);
vmbus_child_driver_unregister(&drv->driver);
return;
}
/*
* blkvsc_probe - Add a new device for this driver
*/
static int blkvsc_probe(struct hv_device *dev)
{
struct storvsc_driver *storvsc_drv =
drv_to_stordrv(dev->device.driver);
struct block_device_context *blkdev = NULL;
struct storvsc_device_info device_info;
struct storvsc_major_info major_info;
int ret = 0;
blkdev = kzalloc(sizeof(struct block_device_context), GFP_KERNEL);
if (!blkdev) {
ret = -ENOMEM;
goto cleanup;
}
INIT_LIST_HEAD(&blkdev->pending_list);
/* Initialize what we can here */
spin_lock_init(&blkdev->lock);
blkdev->request_pool = kmem_cache_create(dev_name(&dev->device),
sizeof(struct blkvsc_request), 0,
SLAB_HWCACHE_ALIGN, NULL);
if (!blkdev->request_pool) {
ret = -ENOMEM;
goto cleanup;
}
ret = blkvsc_device_add(dev, &device_info);
if (ret != 0)
goto cleanup;
blkdev->device_ctx = dev;
/* this identified the device 0 or 1 */
blkdev->target = device_info.target_id;
/* this identified the ide ctrl 0 or 1 */
blkdev->path = device_info.path_id;
dev_set_drvdata(&dev->device, blkdev);
ret = stor_vsc_get_major_info(&device_info, &major_info);
if (ret)
goto cleanup;
if (major_info.do_register) {
ret = register_blkdev(major_info.major, major_info.devname);
if (ret != 0) {
DPRINT_ERR(BLKVSC_DRV,
"register_blkdev() failed! ret %d", ret);
goto remove;
}
}
DPRINT_INFO(BLKVSC_DRV, "blkvsc registered for major %d!!",
major_info.major);
blkdev->gd = alloc_disk(BLKVSC_MINORS);
if (!blkdev->gd) {
ret = -1;
goto cleanup;
}
blkdev->gd->queue = blk_init_queue(blkvsc_request, &blkdev->lock);
blk_queue_max_segment_size(blkdev->gd->queue, PAGE_SIZE);
blk_queue_max_segments(blkdev->gd->queue, MAX_MULTIPAGE_BUFFER_COUNT);
blk_queue_segment_boundary(blkdev->gd->queue, PAGE_SIZE-1);
blk_queue_bounce_limit(blkdev->gd->queue, BLK_BOUNCE_ANY);
blk_queue_dma_alignment(blkdev->gd->queue, 511);
blkdev->gd->major = major_info.major;
if (major_info.index == 1 || major_info.index == 3)
blkdev->gd->first_minor = BLKVSC_MINORS;
else
blkdev->gd->first_minor = 0;
blkdev->gd->fops = &block_ops;
blkdev->gd->events = DISK_EVENT_MEDIA_CHANGE;
blkdev->gd->private_data = blkdev;
blkdev->gd->driverfs_dev = &(blkdev->device_ctx->device);
sprintf(blkdev->gd->disk_name, "hd%c", 'a' + major_info.index);
blkvsc_do_operation(blkdev, DO_INQUIRY);
blkvsc_do_operation(blkdev, DO_CAPACITY);
set_capacity(blkdev->gd, blkdev->capacity * (blkdev->sector_size/512));
blk_queue_logical_block_size(blkdev->gd->queue, blkdev->sector_size);
/* go! */
add_disk(blkdev->gd);
DPRINT_INFO(BLKVSC_DRV, "%s added!! capacity %lu sector_size %d",
blkdev->gd->disk_name, (unsigned long)blkdev->capacity,
blkdev->sector_size);
return ret;
remove:
storvsc_drv->base.dev_rm(dev);
cleanup:
if (blkdev) {
if (blkdev->request_pool) {
kmem_cache_destroy(blkdev->request_pool);
blkdev->request_pool = NULL;
}
kfree(blkdev);
blkdev = NULL;
}
return ret;
}
static void blkvsc_request_completion(struct hv_storvsc_request *request)
{
struct blkvsc_request *blkvsc_req =
(struct blkvsc_request *)request->context;
struct block_device_context *blkdev =
(struct block_device_context *)blkvsc_req->dev;
unsigned long flags;
struct blkvsc_request *comp_req, *tmp;
struct vmscsi_request *vm_srb;
spin_lock_irqsave(&blkdev->lock, flags);
blkdev->num_outstanding_reqs--;
blkvsc_req->group->outstanding--;
/*
* Only start processing when all the blkvsc_reqs are
* completed. This guarantees no out-of-order blkvsc_req
* completion when calling end_that_request_first()
*/
if (blkvsc_req->group->outstanding == 0) {
list_for_each_entry_safe(comp_req, tmp,
&blkvsc_req->group->blkvsc_req_list,
req_entry) {
list_del(&comp_req->req_entry);
vm_srb =
&comp_req->request.vstor_packet.vm_srb;
if (!__blk_end_request(comp_req->req,
(!vm_srb->scsi_status ? 0 : -EIO),
comp_req->sector_count * blkdev->sector_size)) {
/*
* All the sectors have been xferred ie the
* request is done
*/
kmem_cache_free(blkdev->request_pool,
comp_req->group);
}
kmem_cache_free(blkdev->request_pool, comp_req);
}
if (!blkdev->shutting_down) {
blkvsc_do_pending_reqs(blkdev);
blk_start_queue(blkdev->gd->queue);
blkvsc_request(blkdev->gd->queue);
}
}
spin_unlock_irqrestore(&blkdev->lock, flags);
}
static int __init blkvsc_init(void)
{
int ret;
BUILD_BUG_ON(sizeof(sector_t) != 8);
ret = blkvsc_drv_init();
return ret;
}
static void __exit blkvsc_exit(void)
{
blkvsc_drv_exit();
}
MODULE_LICENSE("GPL");
MODULE_VERSION(HV_DRV_VERSION);
MODULE_DESCRIPTION("Microsoft Hyper-V virtual block driver");
module_init(blkvsc_init);
module_exit(blkvsc_exit);
|