2 #include <linux/spinlock.h>
3 #include <linux/slab.h>
4 #include <linux/blkdev.h>
5 #include <linux/hdreg.h>
6 #include <linux/module.h>
7 #include <linux/mutex.h>
8 #include <linux/virtio.h>
9 #include <linux/virtio_blk.h>
10 #include <linux/scatterlist.h>
11 #include <linux/string_helpers.h>
12 #include <scsi/scsi_cmnd.h>
13 #include <linux/idr.h>
14 #include <linux/blk-mq.h>
15 #include <linux/numa.h>
18 #define VQ_NAME_LEN 16
21 static DEFINE_IDA(vd_index_ida);
23 static struct workqueue_struct *virtblk_wq;
25 struct virtio_blk_vq {
28 char name[VQ_NAME_LEN];
29 } ____cacheline_aligned_in_smp;
33 struct virtio_device *vdev;
35 /* The disk structure for the kernel. */
38 /* Block layer tags. */
39 struct blk_mq_tag_set tag_set;
41 /* Process context for config space updates */
42 struct work_struct config_work;
44 /* Lock for config space updates */
45 struct mutex config_lock;
47 /* What host tells us, plus 2 for header & tailer. */
48 unsigned int sg_elems;
50 /* Ida index - used to track minor number allocations. */
55 struct virtio_blk_vq *vqs;
61 struct virtio_blk_outhdr out_hdr;
62 struct virtio_scsi_inhdr in_hdr;
64 struct scatterlist sg[];
67 static inline int virtblk_result(struct virtblk_req *vbr)
69 switch (vbr->status) {
72 case VIRTIO_BLK_S_UNSUPP:
79 static int __virtblk_add_req(struct virtqueue *vq,
80 struct virtblk_req *vbr,
81 struct scatterlist *data_sg,
84 struct scatterlist hdr, status, cmd, sense, inhdr, *sgs[6];
85 unsigned int num_out = 0, num_in = 0;
86 int type = vbr->out_hdr.type & ~VIRTIO_BLK_T_OUT;
88 sg_init_one(&hdr, &vbr->out_hdr, sizeof(vbr->out_hdr));
89 sgs[num_out++] = &hdr;
92 * If this is a packet command we need a couple of additional headers.
93 * Behind the normal outhdr we put a segment with the scsi command
94 * block, and before the normal inhdr we put the sense data and the
95 * inhdr with additional status information.
97 if (type == VIRTIO_BLK_T_SCSI_CMD) {
98 sg_init_one(&cmd, vbr->req->cmd, vbr->req->cmd_len);
99 sgs[num_out++] = &cmd;
103 if (vbr->out_hdr.type & VIRTIO_BLK_T_OUT)
104 sgs[num_out++] = data_sg;
106 sgs[num_out + num_in++] = data_sg;
109 if (type == VIRTIO_BLK_T_SCSI_CMD) {
110 sg_init_one(&sense, vbr->req->sense, SCSI_SENSE_BUFFERSIZE);
111 sgs[num_out + num_in++] = &sense;
112 sg_init_one(&inhdr, &vbr->in_hdr, sizeof(vbr->in_hdr));
113 sgs[num_out + num_in++] = &inhdr;
116 sg_init_one(&status, &vbr->status, sizeof(vbr->status));
117 sgs[num_out + num_in++] = &status;
119 return virtqueue_add_sgs(vq, sgs, num_out, num_in, vbr, GFP_ATOMIC);
122 static inline void virtblk_request_done(struct request *req)
124 struct virtblk_req *vbr = blk_mq_rq_to_pdu(req);
125 int error = virtblk_result(vbr);
127 if (req->cmd_type == REQ_TYPE_BLOCK_PC) {
128 req->resid_len = vbr->in_hdr.residual;
129 req->sense_len = vbr->in_hdr.sense_len;
130 req->errors = vbr->in_hdr.errors;
131 } else if (req->cmd_type == REQ_TYPE_SPECIAL) {
132 req->errors = (error != 0);
135 blk_mq_end_io(req, error);
138 static void virtblk_done(struct virtqueue *vq)
140 struct virtio_blk *vblk = vq->vdev->priv;
141 bool req_done = false;
143 struct virtblk_req *vbr;
147 spin_lock_irqsave(&vblk->vqs[qid].lock, flags);
149 virtqueue_disable_cb(vq);
150 while ((vbr = virtqueue_get_buf(vblk->vqs[qid].vq, &len)) != NULL) {
151 blk_mq_complete_request(vbr->req);
154 if (unlikely(virtqueue_is_broken(vq)))
156 } while (!virtqueue_enable_cb(vq));
158 /* In case queue is stopped waiting for more buffers. */
160 blk_mq_start_stopped_hw_queues(vblk->disk->queue, true);
161 spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags);
164 static int virtio_queue_rq(struct blk_mq_hw_ctx *hctx, struct request *req)
166 struct virtio_blk *vblk = hctx->queue->queuedata;
167 struct virtblk_req *vbr = blk_mq_rq_to_pdu(req);
170 int qid = hctx->queue_num;
171 const bool last = (req->cmd_flags & REQ_END) != 0;
175 BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems);
178 if (req->cmd_flags & REQ_FLUSH) {
179 vbr->out_hdr.type = VIRTIO_BLK_T_FLUSH;
180 vbr->out_hdr.sector = 0;
181 vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
183 switch (req->cmd_type) {
185 vbr->out_hdr.type = 0;
186 vbr->out_hdr.sector = blk_rq_pos(vbr->req);
187 vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
189 case REQ_TYPE_BLOCK_PC:
190 vbr->out_hdr.type = VIRTIO_BLK_T_SCSI_CMD;
191 vbr->out_hdr.sector = 0;
192 vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
194 case REQ_TYPE_SPECIAL:
195 vbr->out_hdr.type = VIRTIO_BLK_T_GET_ID;
196 vbr->out_hdr.sector = 0;
197 vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
200 /* We don't put anything else in the queue. */
205 num = blk_rq_map_sg(hctx->queue, vbr->req, vbr->sg);
207 if (rq_data_dir(vbr->req) == WRITE)
208 vbr->out_hdr.type |= VIRTIO_BLK_T_OUT;
210 vbr->out_hdr.type |= VIRTIO_BLK_T_IN;
213 spin_lock_irqsave(&vblk->vqs[qid].lock, flags);
214 err = __virtblk_add_req(vblk->vqs[qid].vq, vbr, vbr->sg, num);
216 virtqueue_kick(vblk->vqs[qid].vq);
217 blk_mq_stop_hw_queue(hctx);
218 spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags);
219 /* Out of mem doesn't actually happen, since we fall back
220 * to direct descriptors */
221 if (err == -ENOMEM || err == -ENOSPC)
222 return BLK_MQ_RQ_QUEUE_BUSY;
223 return BLK_MQ_RQ_QUEUE_ERROR;
226 if (last && virtqueue_kick_prepare(vblk->vqs[qid].vq))
228 spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags);
231 virtqueue_notify(vblk->vqs[qid].vq);
232 return BLK_MQ_RQ_QUEUE_OK;
235 /* return id (s/n) string for *disk to *id_str
237 static int virtblk_get_id(struct gendisk *disk, char *id_str)
239 struct virtio_blk *vblk = disk->private_data;
244 bio = bio_map_kern(vblk->disk->queue, id_str, VIRTIO_BLK_ID_BYTES,
249 req = blk_make_request(vblk->disk->queue, bio, GFP_KERNEL);
255 req->cmd_type = REQ_TYPE_SPECIAL;
256 err = blk_execute_rq(vblk->disk->queue, vblk->disk, req, false);
257 blk_put_request(req);
262 static int virtblk_ioctl(struct block_device *bdev, fmode_t mode,
263 unsigned int cmd, unsigned long data)
265 struct gendisk *disk = bdev->bd_disk;
266 struct virtio_blk *vblk = disk->private_data;
269 * Only allow the generic SCSI ioctls if the host can support it.
271 if (!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_SCSI))
274 return scsi_cmd_blk_ioctl(bdev, mode, cmd,
275 (void __user *)data);
278 /* We provide getgeo only to please some old bootloader/partitioning tools */
279 static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo)
281 struct virtio_blk *vblk = bd->bd_disk->private_data;
283 /* see if the host passed in geometry config */
284 if (virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_GEOMETRY)) {
285 virtio_cread(vblk->vdev, struct virtio_blk_config,
286 geometry.cylinders, &geo->cylinders);
287 virtio_cread(vblk->vdev, struct virtio_blk_config,
288 geometry.heads, &geo->heads);
289 virtio_cread(vblk->vdev, struct virtio_blk_config,
290 geometry.sectors, &geo->sectors);
292 /* some standard values, similar to sd */
294 geo->sectors = 1 << 5;
295 geo->cylinders = get_capacity(bd->bd_disk) >> 11;
300 static const struct block_device_operations virtblk_fops = {
301 .ioctl = virtblk_ioctl,
302 .owner = THIS_MODULE,
303 .getgeo = virtblk_getgeo,
306 static int index_to_minor(int index)
308 return index << PART_BITS;
311 static int minor_to_index(int minor)
313 return minor >> PART_BITS;
316 static ssize_t virtblk_serial_show(struct device *dev,
317 struct device_attribute *attr, char *buf)
319 struct gendisk *disk = dev_to_disk(dev);
322 /* sysfs gives us a PAGE_SIZE buffer */
323 BUILD_BUG_ON(PAGE_SIZE < VIRTIO_BLK_ID_BYTES);
325 buf[VIRTIO_BLK_ID_BYTES] = '\0';
326 err = virtblk_get_id(disk, buf);
330 if (err == -EIO) /* Unsupported? Make it empty. */
335 DEVICE_ATTR(serial, S_IRUGO, virtblk_serial_show, NULL);
337 static void virtblk_config_changed_work(struct work_struct *work)
339 struct virtio_blk *vblk =
340 container_of(work, struct virtio_blk, config_work);
341 struct virtio_device *vdev = vblk->vdev;
342 struct request_queue *q = vblk->disk->queue;
343 char cap_str_2[10], cap_str_10[10];
344 char *envp[] = { "RESIZE=1", NULL };
347 mutex_lock(&vblk->config_lock);
349 /* Host must always specify the capacity. */
350 virtio_cread(vdev, struct virtio_blk_config, capacity, &capacity);
352 /* If capacity is too big, truncate with warning. */
353 if ((sector_t)capacity != capacity) {
354 dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n",
355 (unsigned long long)capacity);
356 capacity = (sector_t)-1;
359 size = capacity * queue_logical_block_size(q);
360 string_get_size(size, STRING_UNITS_2, cap_str_2, sizeof(cap_str_2));
361 string_get_size(size, STRING_UNITS_10, cap_str_10, sizeof(cap_str_10));
363 dev_notice(&vdev->dev,
364 "new size: %llu %d-byte logical blocks (%s/%s)\n",
365 (unsigned long long)capacity,
366 queue_logical_block_size(q),
367 cap_str_10, cap_str_2);
369 set_capacity(vblk->disk, capacity);
370 revalidate_disk(vblk->disk);
371 kobject_uevent_env(&disk_to_dev(vblk->disk)->kobj, KOBJ_CHANGE, envp);
373 mutex_unlock(&vblk->config_lock);
376 static void virtblk_config_changed(struct virtio_device *vdev)
378 struct virtio_blk *vblk = vdev->priv;
380 queue_work(virtblk_wq, &vblk->config_work);
383 static int init_vq(struct virtio_blk *vblk)
387 vq_callback_t **callbacks;
389 struct virtqueue **vqs;
390 unsigned short num_vqs;
391 struct virtio_device *vdev = vblk->vdev;
393 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_MQ,
394 struct virtio_blk_config, num_queues,
399 vblk->vqs = kmalloc(sizeof(*vblk->vqs) * num_vqs, GFP_KERNEL);
405 names = kmalloc(sizeof(*names) * num_vqs, GFP_KERNEL);
409 callbacks = kmalloc(sizeof(*callbacks) * num_vqs, GFP_KERNEL);
413 vqs = kmalloc(sizeof(*vqs) * num_vqs, GFP_KERNEL);
417 for (i = 0; i < num_vqs; i++) {
418 callbacks[i] = virtblk_done;
419 snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req.%d", i);
420 names[i] = vblk->vqs[i].name;
423 /* Discover virtqueues and write information to configuration. */
424 err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names);
428 for (i = 0; i < num_vqs; i++) {
429 spin_lock_init(&vblk->vqs[i].lock);
430 vblk->vqs[i].vq = vqs[i];
432 vblk->num_vqs = num_vqs;
448 * Legacy naming scheme used for virtio devices. We are stuck with it for
449 * virtio blk but don't ever use it for any new driver.
451 static int virtblk_name_format(char *prefix, int index, char *buf, int buflen)
453 const int base = 'z' - 'a' + 1;
454 char *begin = buf + strlen(prefix);
455 char *end = buf + buflen;
465 *--p = 'a' + (index % unit);
466 index = (index / unit) - 1;
467 } while (index >= 0);
469 memmove(begin, p, end - p);
470 memcpy(buf, prefix, strlen(prefix));
475 static int virtblk_get_cache_mode(struct virtio_device *vdev)
480 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE,
481 struct virtio_blk_config, wce,
484 writeback = virtio_has_feature(vdev, VIRTIO_BLK_F_WCE);
489 static void virtblk_update_cache_mode(struct virtio_device *vdev)
491 u8 writeback = virtblk_get_cache_mode(vdev);
492 struct virtio_blk *vblk = vdev->priv;
495 blk_queue_flush(vblk->disk->queue, REQ_FLUSH);
497 blk_queue_flush(vblk->disk->queue, 0);
499 revalidate_disk(vblk->disk);
502 static const char *const virtblk_cache_types[] = {
503 "write through", "write back"
507 virtblk_cache_type_store(struct device *dev, struct device_attribute *attr,
508 const char *buf, size_t count)
510 struct gendisk *disk = dev_to_disk(dev);
511 struct virtio_blk *vblk = disk->private_data;
512 struct virtio_device *vdev = vblk->vdev;
515 BUG_ON(!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_CONFIG_WCE));
516 for (i = ARRAY_SIZE(virtblk_cache_types); --i >= 0; )
517 if (sysfs_streq(buf, virtblk_cache_types[i]))
523 virtio_cwrite8(vdev, offsetof(struct virtio_blk_config, wce), i);
524 virtblk_update_cache_mode(vdev);
529 virtblk_cache_type_show(struct device *dev, struct device_attribute *attr,
532 struct gendisk *disk = dev_to_disk(dev);
533 struct virtio_blk *vblk = disk->private_data;
534 u8 writeback = virtblk_get_cache_mode(vblk->vdev);
536 BUG_ON(writeback >= ARRAY_SIZE(virtblk_cache_types));
537 return snprintf(buf, 40, "%s\n", virtblk_cache_types[writeback]);
540 static const struct device_attribute dev_attr_cache_type_ro =
541 __ATTR(cache_type, S_IRUGO,
542 virtblk_cache_type_show, NULL);
543 static const struct device_attribute dev_attr_cache_type_rw =
544 __ATTR(cache_type, S_IRUGO|S_IWUSR,
545 virtblk_cache_type_show, virtblk_cache_type_store);
547 static int virtblk_init_request(void *data, struct request *rq,
548 unsigned int hctx_idx, unsigned int request_idx,
549 unsigned int numa_node)
551 struct virtio_blk *vblk = data;
552 struct virtblk_req *vbr = blk_mq_rq_to_pdu(rq);
554 sg_init_table(vbr->sg, vblk->sg_elems);
558 static struct blk_mq_ops virtio_mq_ops = {
559 .queue_rq = virtio_queue_rq,
560 .map_queue = blk_mq_map_queue,
561 .complete = virtblk_request_done,
562 .init_request = virtblk_init_request,
565 static unsigned int virtblk_queue_depth;
566 module_param_named(queue_depth, virtblk_queue_depth, uint, 0444);
568 static int virtblk_probe(struct virtio_device *vdev)
570 struct virtio_blk *vblk;
571 struct request_queue *q;
575 u32 v, blk_size, sg_elems, opt_io_size;
577 u8 physical_block_exp, alignment_offset;
579 err = ida_simple_get(&vd_index_ida, 0, minor_to_index(1 << MINORBITS),
585 /* We need to know how many segments before we allocate. */
586 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_SEG_MAX,
587 struct virtio_blk_config, seg_max,
590 /* We need at least one SG element, whatever they say. */
591 if (err || !sg_elems)
594 /* We need an extra sg elements at head and tail. */
596 vdev->priv = vblk = kmalloc(sizeof(*vblk), GFP_KERNEL);
603 vblk->sg_elems = sg_elems;
604 mutex_init(&vblk->config_lock);
606 INIT_WORK(&vblk->config_work, virtblk_config_changed_work);
612 /* FIXME: How many partitions? How long is a piece of string? */
613 vblk->disk = alloc_disk(1 << PART_BITS);
619 /* Default queue sizing is to fill the ring. */
620 if (!virtblk_queue_depth) {
621 virtblk_queue_depth = vblk->vqs[0].vq->num_free;
622 /* ... but without indirect descs, we use 2 descs per req */
623 if (!virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC))
624 virtblk_queue_depth /= 2;
627 memset(&vblk->tag_set, 0, sizeof(vblk->tag_set));
628 vblk->tag_set.ops = &virtio_mq_ops;
629 vblk->tag_set.queue_depth = virtblk_queue_depth;
630 vblk->tag_set.numa_node = NUMA_NO_NODE;
631 vblk->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
632 vblk->tag_set.cmd_size =
633 sizeof(struct virtblk_req) +
634 sizeof(struct scatterlist) * sg_elems;
635 vblk->tag_set.driver_data = vblk;
636 vblk->tag_set.nr_hw_queues = vblk->num_vqs;
638 err = blk_mq_alloc_tag_set(&vblk->tag_set);
642 q = vblk->disk->queue = blk_mq_init_queue(&vblk->tag_set);
650 virtblk_name_format("vd", index, vblk->disk->disk_name, DISK_NAME_LEN);
652 vblk->disk->major = major;
653 vblk->disk->first_minor = index_to_minor(index);
654 vblk->disk->private_data = vblk;
655 vblk->disk->fops = &virtblk_fops;
656 vblk->disk->driverfs_dev = &vdev->dev;
659 /* configure queue flush support */
660 virtblk_update_cache_mode(vdev);
662 /* If disk is read-only in the host, the guest should obey */
663 if (virtio_has_feature(vdev, VIRTIO_BLK_F_RO))
664 set_disk_ro(vblk->disk, 1);
666 /* Host must always specify the capacity. */
667 virtio_cread(vdev, struct virtio_blk_config, capacity, &cap);
669 /* If capacity is too big, truncate with warning. */
670 if ((sector_t)cap != cap) {
671 dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n",
672 (unsigned long long)cap);
675 set_capacity(vblk->disk, cap);
677 /* We can handle whatever the host told us to handle. */
678 blk_queue_max_segments(q, vblk->sg_elems-2);
680 /* No need to bounce any requests */
681 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
683 /* No real sector limit. */
684 blk_queue_max_hw_sectors(q, -1U);
686 /* Host can optionally specify maximum segment size and number of
688 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_SIZE_MAX,
689 struct virtio_blk_config, size_max, &v);
691 blk_queue_max_segment_size(q, v);
693 blk_queue_max_segment_size(q, -1U);
695 /* Host can optionally specify the block size of the device */
696 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_BLK_SIZE,
697 struct virtio_blk_config, blk_size,
700 blk_queue_logical_block_size(q, blk_size);
702 blk_size = queue_logical_block_size(q);
704 /* Use topology information if available */
705 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY,
706 struct virtio_blk_config, physical_block_exp,
707 &physical_block_exp);
708 if (!err && physical_block_exp)
709 blk_queue_physical_block_size(q,
710 blk_size * (1 << physical_block_exp));
712 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY,
713 struct virtio_blk_config, alignment_offset,
715 if (!err && alignment_offset)
716 blk_queue_alignment_offset(q, blk_size * alignment_offset);
718 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY,
719 struct virtio_blk_config, min_io_size,
721 if (!err && min_io_size)
722 blk_queue_io_min(q, blk_size * min_io_size);
724 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY,
725 struct virtio_blk_config, opt_io_size,
727 if (!err && opt_io_size)
728 blk_queue_io_opt(q, blk_size * opt_io_size);
730 add_disk(vblk->disk);
731 err = device_create_file(disk_to_dev(vblk->disk), &dev_attr_serial);
735 if (virtio_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE))
736 err = device_create_file(disk_to_dev(vblk->disk),
737 &dev_attr_cache_type_rw);
739 err = device_create_file(disk_to_dev(vblk->disk),
740 &dev_attr_cache_type_ro);
746 del_gendisk(vblk->disk);
747 blk_cleanup_queue(vblk->disk->queue);
749 blk_mq_free_tag_set(&vblk->tag_set);
751 put_disk(vblk->disk);
753 vdev->config->del_vqs(vdev);
757 ida_simple_remove(&vd_index_ida, index);
762 static void virtblk_remove(struct virtio_device *vdev)
764 struct virtio_blk *vblk = vdev->priv;
765 int index = vblk->index;
768 /* Make sure no work handler is accessing the device. */
769 flush_work(&vblk->config_work);
771 del_gendisk(vblk->disk);
772 blk_cleanup_queue(vblk->disk->queue);
774 blk_mq_free_tag_set(&vblk->tag_set);
776 /* Stop all the virtqueues. */
777 vdev->config->reset(vdev);
779 refc = atomic_read(&disk_to_dev(vblk->disk)->kobj.kref.refcount);
780 put_disk(vblk->disk);
781 vdev->config->del_vqs(vdev);
785 /* Only free device id if we don't have any users */
787 ida_simple_remove(&vd_index_ida, index);
790 #ifdef CONFIG_PM_SLEEP
791 static int virtblk_freeze(struct virtio_device *vdev)
793 struct virtio_blk *vblk = vdev->priv;
795 /* Ensure we don't receive any more interrupts */
796 vdev->config->reset(vdev);
798 /* Make sure no work handler is accessing the device. */
799 flush_work(&vblk->config_work);
801 blk_mq_stop_hw_queues(vblk->disk->queue);
803 vdev->config->del_vqs(vdev);
807 static int virtblk_restore(struct virtio_device *vdev)
809 struct virtio_blk *vblk = vdev->priv;
812 ret = init_vq(vdev->priv);
814 blk_mq_start_stopped_hw_queues(vblk->disk->queue, true);
820 static const struct virtio_device_id id_table[] = {
821 { VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID },
825 static unsigned int features[] = {
826 VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY,
827 VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, VIRTIO_BLK_F_SCSI,
828 VIRTIO_BLK_F_WCE, VIRTIO_BLK_F_TOPOLOGY, VIRTIO_BLK_F_CONFIG_WCE,
832 static struct virtio_driver virtio_blk = {
833 .feature_table = features,
834 .feature_table_size = ARRAY_SIZE(features),
835 .driver.name = KBUILD_MODNAME,
836 .driver.owner = THIS_MODULE,
837 .id_table = id_table,
838 .probe = virtblk_probe,
839 .remove = virtblk_remove,
840 .config_changed = virtblk_config_changed,
841 #ifdef CONFIG_PM_SLEEP
842 .freeze = virtblk_freeze,
843 .restore = virtblk_restore,
847 static int __init init(void)
851 virtblk_wq = alloc_workqueue("virtio-blk", 0, 0);
855 major = register_blkdev(0, "virtblk");
858 goto out_destroy_workqueue;
861 error = register_virtio_driver(&virtio_blk);
863 goto out_unregister_blkdev;
866 out_unregister_blkdev:
867 unregister_blkdev(major, "virtblk");
868 out_destroy_workqueue:
869 destroy_workqueue(virtblk_wq);
873 static void __exit fini(void)
875 unregister_blkdev(major, "virtblk");
876 unregister_virtio_driver(&virtio_blk);
877 destroy_workqueue(virtblk_wq);
882 MODULE_DEVICE_TABLE(virtio, id_table);
883 MODULE_DESCRIPTION("Virtio block driver");
884 MODULE_LICENSE("GPL");