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 /* enable config space updates */
50 /* What host tells us, plus 2 for header & tailer. */
51 unsigned int sg_elems;
53 /* Ida index - used to track minor number allocations. */
58 struct virtio_blk_vq *vqs;
64 struct virtio_blk_outhdr out_hdr;
65 struct virtio_scsi_inhdr in_hdr;
67 struct scatterlist sg[];
70 static inline int virtblk_result(struct virtblk_req *vbr)
72 switch (vbr->status) {
75 case VIRTIO_BLK_S_UNSUPP:
82 static int __virtblk_add_req(struct virtqueue *vq,
83 struct virtblk_req *vbr,
84 struct scatterlist *data_sg,
87 struct scatterlist hdr, status, cmd, sense, inhdr, *sgs[6];
88 unsigned int num_out = 0, num_in = 0;
89 int type = vbr->out_hdr.type & ~VIRTIO_BLK_T_OUT;
91 sg_init_one(&hdr, &vbr->out_hdr, sizeof(vbr->out_hdr));
92 sgs[num_out++] = &hdr;
95 * If this is a packet command we need a couple of additional headers.
96 * Behind the normal outhdr we put a segment with the scsi command
97 * block, and before the normal inhdr we put the sense data and the
98 * inhdr with additional status information.
100 if (type == VIRTIO_BLK_T_SCSI_CMD) {
101 sg_init_one(&cmd, vbr->req->cmd, vbr->req->cmd_len);
102 sgs[num_out++] = &cmd;
106 if (vbr->out_hdr.type & VIRTIO_BLK_T_OUT)
107 sgs[num_out++] = data_sg;
109 sgs[num_out + num_in++] = data_sg;
112 if (type == VIRTIO_BLK_T_SCSI_CMD) {
113 sg_init_one(&sense, vbr->req->sense, SCSI_SENSE_BUFFERSIZE);
114 sgs[num_out + num_in++] = &sense;
115 sg_init_one(&inhdr, &vbr->in_hdr, sizeof(vbr->in_hdr));
116 sgs[num_out + num_in++] = &inhdr;
119 sg_init_one(&status, &vbr->status, sizeof(vbr->status));
120 sgs[num_out + num_in++] = &status;
122 return virtqueue_add_sgs(vq, sgs, num_out, num_in, vbr, GFP_ATOMIC);
125 static inline void virtblk_request_done(struct request *req)
127 struct virtblk_req *vbr = blk_mq_rq_to_pdu(req);
128 int error = virtblk_result(vbr);
130 if (req->cmd_type == REQ_TYPE_BLOCK_PC) {
131 req->resid_len = vbr->in_hdr.residual;
132 req->sense_len = vbr->in_hdr.sense_len;
133 req->errors = vbr->in_hdr.errors;
134 } else if (req->cmd_type == REQ_TYPE_SPECIAL) {
135 req->errors = (error != 0);
138 blk_mq_end_request(req, error);
141 static void virtblk_done(struct virtqueue *vq)
143 struct virtio_blk *vblk = vq->vdev->priv;
144 bool req_done = false;
146 struct virtblk_req *vbr;
150 spin_lock_irqsave(&vblk->vqs[qid].lock, flags);
152 virtqueue_disable_cb(vq);
153 while ((vbr = virtqueue_get_buf(vblk->vqs[qid].vq, &len)) != NULL) {
154 blk_mq_complete_request(vbr->req);
157 if (unlikely(virtqueue_is_broken(vq)))
159 } while (!virtqueue_enable_cb(vq));
161 /* In case queue is stopped waiting for more buffers. */
163 blk_mq_start_stopped_hw_queues(vblk->disk->queue, true);
164 spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags);
167 static int virtio_queue_rq(struct blk_mq_hw_ctx *hctx, struct request *req,
170 struct virtio_blk *vblk = hctx->queue->queuedata;
171 struct virtblk_req *vbr = blk_mq_rq_to_pdu(req);
174 int qid = hctx->queue_num;
178 BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems);
181 if (req->cmd_flags & REQ_FLUSH) {
182 vbr->out_hdr.type = VIRTIO_BLK_T_FLUSH;
183 vbr->out_hdr.sector = 0;
184 vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
186 switch (req->cmd_type) {
188 vbr->out_hdr.type = 0;
189 vbr->out_hdr.sector = blk_rq_pos(vbr->req);
190 vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
192 case REQ_TYPE_BLOCK_PC:
193 vbr->out_hdr.type = VIRTIO_BLK_T_SCSI_CMD;
194 vbr->out_hdr.sector = 0;
195 vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
197 case REQ_TYPE_SPECIAL:
198 vbr->out_hdr.type = VIRTIO_BLK_T_GET_ID;
199 vbr->out_hdr.sector = 0;
200 vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
203 /* We don't put anything else in the queue. */
208 blk_mq_start_request(req);
210 num = blk_rq_map_sg(hctx->queue, vbr->req, vbr->sg);
212 if (rq_data_dir(vbr->req) == WRITE)
213 vbr->out_hdr.type |= VIRTIO_BLK_T_OUT;
215 vbr->out_hdr.type |= VIRTIO_BLK_T_IN;
218 spin_lock_irqsave(&vblk->vqs[qid].lock, flags);
219 err = __virtblk_add_req(vblk->vqs[qid].vq, vbr, vbr->sg, num);
221 virtqueue_kick(vblk->vqs[qid].vq);
222 blk_mq_stop_hw_queue(hctx);
223 spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags);
224 /* Out of mem doesn't actually happen, since we fall back
225 * to direct descriptors */
226 if (err == -ENOMEM || err == -ENOSPC)
227 return BLK_MQ_RQ_QUEUE_BUSY;
228 return BLK_MQ_RQ_QUEUE_ERROR;
231 if (last && virtqueue_kick_prepare(vblk->vqs[qid].vq))
233 spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags);
236 virtqueue_notify(vblk->vqs[qid].vq);
237 return BLK_MQ_RQ_QUEUE_OK;
240 /* return id (s/n) string for *disk to *id_str
242 static int virtblk_get_id(struct gendisk *disk, char *id_str)
244 struct virtio_blk *vblk = disk->private_data;
249 bio = bio_map_kern(vblk->disk->queue, id_str, VIRTIO_BLK_ID_BYTES,
254 req = blk_make_request(vblk->disk->queue, bio, GFP_KERNEL);
260 req->cmd_type = REQ_TYPE_SPECIAL;
261 err = blk_execute_rq(vblk->disk->queue, vblk->disk, req, false);
262 blk_put_request(req);
267 static int virtblk_ioctl(struct block_device *bdev, fmode_t mode,
268 unsigned int cmd, unsigned long data)
270 struct gendisk *disk = bdev->bd_disk;
271 struct virtio_blk *vblk = disk->private_data;
274 * Only allow the generic SCSI ioctls if the host can support it.
276 if (!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_SCSI))
279 return scsi_cmd_blk_ioctl(bdev, mode, cmd,
280 (void __user *)data);
283 /* We provide getgeo only to please some old bootloader/partitioning tools */
284 static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo)
286 struct virtio_blk *vblk = bd->bd_disk->private_data;
288 /* see if the host passed in geometry config */
289 if (virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_GEOMETRY)) {
290 virtio_cread(vblk->vdev, struct virtio_blk_config,
291 geometry.cylinders, &geo->cylinders);
292 virtio_cread(vblk->vdev, struct virtio_blk_config,
293 geometry.heads, &geo->heads);
294 virtio_cread(vblk->vdev, struct virtio_blk_config,
295 geometry.sectors, &geo->sectors);
297 /* some standard values, similar to sd */
299 geo->sectors = 1 << 5;
300 geo->cylinders = get_capacity(bd->bd_disk) >> 11;
305 static const struct block_device_operations virtblk_fops = {
306 .ioctl = virtblk_ioctl,
307 .owner = THIS_MODULE,
308 .getgeo = virtblk_getgeo,
311 static int index_to_minor(int index)
313 return index << PART_BITS;
316 static int minor_to_index(int minor)
318 return minor >> PART_BITS;
321 static ssize_t virtblk_serial_show(struct device *dev,
322 struct device_attribute *attr, char *buf)
324 struct gendisk *disk = dev_to_disk(dev);
327 /* sysfs gives us a PAGE_SIZE buffer */
328 BUILD_BUG_ON(PAGE_SIZE < VIRTIO_BLK_ID_BYTES);
330 buf[VIRTIO_BLK_ID_BYTES] = '\0';
331 err = virtblk_get_id(disk, buf);
335 if (err == -EIO) /* Unsupported? Make it empty. */
340 DEVICE_ATTR(serial, S_IRUGO, virtblk_serial_show, NULL);
342 static void virtblk_config_changed_work(struct work_struct *work)
344 struct virtio_blk *vblk =
345 container_of(work, struct virtio_blk, config_work);
346 struct virtio_device *vdev = vblk->vdev;
347 struct request_queue *q = vblk->disk->queue;
348 char cap_str_2[10], cap_str_10[10];
349 char *envp[] = { "RESIZE=1", NULL };
352 mutex_lock(&vblk->config_lock);
353 if (!vblk->config_enable)
356 /* Host must always specify the capacity. */
357 virtio_cread(vdev, struct virtio_blk_config, capacity, &capacity);
359 /* If capacity is too big, truncate with warning. */
360 if ((sector_t)capacity != capacity) {
361 dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n",
362 (unsigned long long)capacity);
363 capacity = (sector_t)-1;
366 size = capacity * queue_logical_block_size(q);
367 string_get_size(size, STRING_UNITS_2, cap_str_2, sizeof(cap_str_2));
368 string_get_size(size, STRING_UNITS_10, cap_str_10, sizeof(cap_str_10));
370 dev_notice(&vdev->dev,
371 "new size: %llu %d-byte logical blocks (%s/%s)\n",
372 (unsigned long long)capacity,
373 queue_logical_block_size(q),
374 cap_str_10, cap_str_2);
376 set_capacity(vblk->disk, capacity);
377 revalidate_disk(vblk->disk);
378 kobject_uevent_env(&disk_to_dev(vblk->disk)->kobj, KOBJ_CHANGE, envp);
380 mutex_unlock(&vblk->config_lock);
383 static void virtblk_config_changed(struct virtio_device *vdev)
385 struct virtio_blk *vblk = vdev->priv;
387 queue_work(virtblk_wq, &vblk->config_work);
390 static int init_vq(struct virtio_blk *vblk)
394 vq_callback_t **callbacks;
396 struct virtqueue **vqs;
397 unsigned short num_vqs;
398 struct virtio_device *vdev = vblk->vdev;
400 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_MQ,
401 struct virtio_blk_config, num_queues,
406 vblk->vqs = kmalloc(sizeof(*vblk->vqs) * num_vqs, GFP_KERNEL);
412 names = kmalloc(sizeof(*names) * num_vqs, GFP_KERNEL);
416 callbacks = kmalloc(sizeof(*callbacks) * num_vqs, GFP_KERNEL);
420 vqs = kmalloc(sizeof(*vqs) * num_vqs, GFP_KERNEL);
424 for (i = 0; i < num_vqs; i++) {
425 callbacks[i] = virtblk_done;
426 snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req.%d", i);
427 names[i] = vblk->vqs[i].name;
430 /* Discover virtqueues and write information to configuration. */
431 err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names);
435 for (i = 0; i < num_vqs; i++) {
436 spin_lock_init(&vblk->vqs[i].lock);
437 vblk->vqs[i].vq = vqs[i];
439 vblk->num_vqs = num_vqs;
455 * Legacy naming scheme used for virtio devices. We are stuck with it for
456 * virtio blk but don't ever use it for any new driver.
458 static int virtblk_name_format(char *prefix, int index, char *buf, int buflen)
460 const int base = 'z' - 'a' + 1;
461 char *begin = buf + strlen(prefix);
462 char *end = buf + buflen;
472 *--p = 'a' + (index % unit);
473 index = (index / unit) - 1;
474 } while (index >= 0);
476 memmove(begin, p, end - p);
477 memcpy(buf, prefix, strlen(prefix));
482 static int virtblk_get_cache_mode(struct virtio_device *vdev)
487 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE,
488 struct virtio_blk_config, wce,
491 writeback = virtio_has_feature(vdev, VIRTIO_BLK_F_WCE);
496 static void virtblk_update_cache_mode(struct virtio_device *vdev)
498 u8 writeback = virtblk_get_cache_mode(vdev);
499 struct virtio_blk *vblk = vdev->priv;
502 blk_queue_flush(vblk->disk->queue, REQ_FLUSH);
504 blk_queue_flush(vblk->disk->queue, 0);
506 revalidate_disk(vblk->disk);
509 static const char *const virtblk_cache_types[] = {
510 "write through", "write back"
514 virtblk_cache_type_store(struct device *dev, struct device_attribute *attr,
515 const char *buf, size_t count)
517 struct gendisk *disk = dev_to_disk(dev);
518 struct virtio_blk *vblk = disk->private_data;
519 struct virtio_device *vdev = vblk->vdev;
522 BUG_ON(!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_CONFIG_WCE));
523 for (i = ARRAY_SIZE(virtblk_cache_types); --i >= 0; )
524 if (sysfs_streq(buf, virtblk_cache_types[i]))
530 virtio_cwrite8(vdev, offsetof(struct virtio_blk_config, wce), i);
531 virtblk_update_cache_mode(vdev);
536 virtblk_cache_type_show(struct device *dev, struct device_attribute *attr,
539 struct gendisk *disk = dev_to_disk(dev);
540 struct virtio_blk *vblk = disk->private_data;
541 u8 writeback = virtblk_get_cache_mode(vblk->vdev);
543 BUG_ON(writeback >= ARRAY_SIZE(virtblk_cache_types));
544 return snprintf(buf, 40, "%s\n", virtblk_cache_types[writeback]);
547 static const struct device_attribute dev_attr_cache_type_ro =
548 __ATTR(cache_type, S_IRUGO,
549 virtblk_cache_type_show, NULL);
550 static const struct device_attribute dev_attr_cache_type_rw =
551 __ATTR(cache_type, S_IRUGO|S_IWUSR,
552 virtblk_cache_type_show, virtblk_cache_type_store);
554 static int virtblk_init_request(void *data, struct request *rq,
555 unsigned int hctx_idx, unsigned int request_idx,
556 unsigned int numa_node)
558 struct virtio_blk *vblk = data;
559 struct virtblk_req *vbr = blk_mq_rq_to_pdu(rq);
561 sg_init_table(vbr->sg, vblk->sg_elems);
565 static struct blk_mq_ops virtio_mq_ops = {
566 .queue_rq = virtio_queue_rq,
567 .map_queue = blk_mq_map_queue,
568 .complete = virtblk_request_done,
569 .init_request = virtblk_init_request,
572 static unsigned int virtblk_queue_depth;
573 module_param_named(queue_depth, virtblk_queue_depth, uint, 0444);
575 static int virtblk_probe(struct virtio_device *vdev)
577 struct virtio_blk *vblk;
578 struct request_queue *q;
582 u32 v, blk_size, sg_elems, opt_io_size;
584 u8 physical_block_exp, alignment_offset;
586 err = ida_simple_get(&vd_index_ida, 0, minor_to_index(1 << MINORBITS),
592 /* We need to know how many segments before we allocate. */
593 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_SEG_MAX,
594 struct virtio_blk_config, seg_max,
597 /* We need at least one SG element, whatever they say. */
598 if (err || !sg_elems)
601 /* We need an extra sg elements at head and tail. */
603 vdev->priv = vblk = kmalloc(sizeof(*vblk), GFP_KERNEL);
610 vblk->sg_elems = sg_elems;
611 mutex_init(&vblk->config_lock);
613 INIT_WORK(&vblk->config_work, virtblk_config_changed_work);
614 vblk->config_enable = true;
620 /* FIXME: How many partitions? How long is a piece of string? */
621 vblk->disk = alloc_disk(1 << PART_BITS);
627 /* Default queue sizing is to fill the ring. */
628 if (!virtblk_queue_depth) {
629 virtblk_queue_depth = vblk->vqs[0].vq->num_free;
630 /* ... but without indirect descs, we use 2 descs per req */
631 if (!virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC))
632 virtblk_queue_depth /= 2;
635 memset(&vblk->tag_set, 0, sizeof(vblk->tag_set));
636 vblk->tag_set.ops = &virtio_mq_ops;
637 vblk->tag_set.queue_depth = virtblk_queue_depth;
638 vblk->tag_set.numa_node = NUMA_NO_NODE;
639 vblk->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
640 vblk->tag_set.cmd_size =
641 sizeof(struct virtblk_req) +
642 sizeof(struct scatterlist) * sg_elems;
643 vblk->tag_set.driver_data = vblk;
644 vblk->tag_set.nr_hw_queues = vblk->num_vqs;
646 err = blk_mq_alloc_tag_set(&vblk->tag_set);
650 q = vblk->disk->queue = blk_mq_init_queue(&vblk->tag_set);
658 virtblk_name_format("vd", index, vblk->disk->disk_name, DISK_NAME_LEN);
660 vblk->disk->major = major;
661 vblk->disk->first_minor = index_to_minor(index);
662 vblk->disk->private_data = vblk;
663 vblk->disk->fops = &virtblk_fops;
664 vblk->disk->driverfs_dev = &vdev->dev;
667 /* configure queue flush support */
668 virtblk_update_cache_mode(vdev);
670 /* If disk is read-only in the host, the guest should obey */
671 if (virtio_has_feature(vdev, VIRTIO_BLK_F_RO))
672 set_disk_ro(vblk->disk, 1);
674 /* Host must always specify the capacity. */
675 virtio_cread(vdev, struct virtio_blk_config, capacity, &cap);
677 /* If capacity is too big, truncate with warning. */
678 if ((sector_t)cap != cap) {
679 dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n",
680 (unsigned long long)cap);
683 set_capacity(vblk->disk, cap);
685 /* We can handle whatever the host told us to handle. */
686 blk_queue_max_segments(q, vblk->sg_elems-2);
688 /* No need to bounce any requests */
689 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
691 /* No real sector limit. */
692 blk_queue_max_hw_sectors(q, -1U);
694 /* Host can optionally specify maximum segment size and number of
696 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_SIZE_MAX,
697 struct virtio_blk_config, size_max, &v);
699 blk_queue_max_segment_size(q, v);
701 blk_queue_max_segment_size(q, -1U);
703 /* Host can optionally specify the block size of the device */
704 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_BLK_SIZE,
705 struct virtio_blk_config, blk_size,
708 blk_queue_logical_block_size(q, blk_size);
710 blk_size = queue_logical_block_size(q);
712 /* Use topology information if available */
713 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY,
714 struct virtio_blk_config, physical_block_exp,
715 &physical_block_exp);
716 if (!err && physical_block_exp)
717 blk_queue_physical_block_size(q,
718 blk_size * (1 << physical_block_exp));
720 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY,
721 struct virtio_blk_config, alignment_offset,
723 if (!err && alignment_offset)
724 blk_queue_alignment_offset(q, blk_size * alignment_offset);
726 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY,
727 struct virtio_blk_config, min_io_size,
729 if (!err && min_io_size)
730 blk_queue_io_min(q, blk_size * min_io_size);
732 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY,
733 struct virtio_blk_config, opt_io_size,
735 if (!err && opt_io_size)
736 blk_queue_io_opt(q, blk_size * opt_io_size);
738 add_disk(vblk->disk);
739 err = device_create_file(disk_to_dev(vblk->disk), &dev_attr_serial);
743 if (virtio_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE))
744 err = device_create_file(disk_to_dev(vblk->disk),
745 &dev_attr_cache_type_rw);
747 err = device_create_file(disk_to_dev(vblk->disk),
748 &dev_attr_cache_type_ro);
754 del_gendisk(vblk->disk);
755 blk_cleanup_queue(vblk->disk->queue);
757 blk_mq_free_tag_set(&vblk->tag_set);
759 put_disk(vblk->disk);
761 vdev->config->del_vqs(vdev);
765 ida_simple_remove(&vd_index_ida, index);
770 static void virtblk_remove(struct virtio_device *vdev)
772 struct virtio_blk *vblk = vdev->priv;
773 int index = vblk->index;
776 /* Prevent config work handler from accessing the device. */
777 mutex_lock(&vblk->config_lock);
778 vblk->config_enable = false;
779 mutex_unlock(&vblk->config_lock);
781 del_gendisk(vblk->disk);
782 blk_cleanup_queue(vblk->disk->queue);
784 blk_mq_free_tag_set(&vblk->tag_set);
786 /* Stop all the virtqueues. */
787 vdev->config->reset(vdev);
789 flush_work(&vblk->config_work);
791 refc = atomic_read(&disk_to_dev(vblk->disk)->kobj.kref.refcount);
792 put_disk(vblk->disk);
793 vdev->config->del_vqs(vdev);
797 /* Only free device id if we don't have any users */
799 ida_simple_remove(&vd_index_ida, index);
802 #ifdef CONFIG_PM_SLEEP
803 static int virtblk_freeze(struct virtio_device *vdev)
805 struct virtio_blk *vblk = vdev->priv;
807 /* Ensure we don't receive any more interrupts */
808 vdev->config->reset(vdev);
810 /* Prevent config work handler from accessing the device. */
811 mutex_lock(&vblk->config_lock);
812 vblk->config_enable = false;
813 mutex_unlock(&vblk->config_lock);
815 flush_work(&vblk->config_work);
817 blk_mq_stop_hw_queues(vblk->disk->queue);
819 vdev->config->del_vqs(vdev);
823 static int virtblk_restore(struct virtio_device *vdev)
825 struct virtio_blk *vblk = vdev->priv;
828 vblk->config_enable = true;
829 ret = init_vq(vdev->priv);
831 blk_mq_start_stopped_hw_queues(vblk->disk->queue, true);
837 static const struct virtio_device_id id_table[] = {
838 { VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID },
842 static unsigned int features[] = {
843 VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY,
844 VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, VIRTIO_BLK_F_SCSI,
845 VIRTIO_BLK_F_WCE, VIRTIO_BLK_F_TOPOLOGY, VIRTIO_BLK_F_CONFIG_WCE,
849 static struct virtio_driver virtio_blk = {
850 .feature_table = features,
851 .feature_table_size = ARRAY_SIZE(features),
852 .driver.name = KBUILD_MODNAME,
853 .driver.owner = THIS_MODULE,
854 .id_table = id_table,
855 .probe = virtblk_probe,
856 .remove = virtblk_remove,
857 .config_changed = virtblk_config_changed,
858 #ifdef CONFIG_PM_SLEEP
859 .freeze = virtblk_freeze,
860 .restore = virtblk_restore,
864 static int __init init(void)
868 virtblk_wq = alloc_workqueue("virtio-blk", 0, 0);
872 major = register_blkdev(0, "virtblk");
875 goto out_destroy_workqueue;
878 error = register_virtio_driver(&virtio_blk);
880 goto out_unregister_blkdev;
883 out_unregister_blkdev:
884 unregister_blkdev(major, "virtblk");
885 out_destroy_workqueue:
886 destroy_workqueue(virtblk_wq);
890 static void __exit fini(void)
892 unregister_blkdev(major, "virtblk");
893 unregister_virtio_driver(&virtio_blk);
894 destroy_workqueue(virtblk_wq);
899 MODULE_DEVICE_TABLE(virtio, id_table);
900 MODULE_DESCRIPTION("Virtio block driver");
901 MODULE_LICENSE("GPL");