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;
32 struct virtio_device *vdev;
34 /* The disk structure for the kernel. */
37 /* Block layer tags. */
38 struct blk_mq_tag_set tag_set;
40 /* Process context for config space updates */
41 struct work_struct config_work;
43 /* What host tells us, plus 2 for header & tailer. */
44 unsigned int sg_elems;
46 /* Ida index - used to track minor number allocations. */
51 struct virtio_blk_vq *vqs;
56 struct virtio_blk_outhdr out_hdr;
57 struct virtio_scsi_inhdr in_hdr;
59 u8 sense[SCSI_SENSE_BUFFERSIZE];
60 struct scatterlist sg[];
63 static inline int virtblk_result(struct virtblk_req *vbr)
65 switch (vbr->status) {
68 case VIRTIO_BLK_S_UNSUPP:
75 static int __virtblk_add_req(struct virtqueue *vq,
76 struct virtblk_req *vbr,
77 struct scatterlist *data_sg,
80 struct scatterlist hdr, status, cmd, sense, inhdr, *sgs[6];
81 unsigned int num_out = 0, num_in = 0;
82 __virtio32 type = vbr->out_hdr.type & ~cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_OUT);
84 sg_init_one(&hdr, &vbr->out_hdr, sizeof(vbr->out_hdr));
85 sgs[num_out++] = &hdr;
88 * If this is a packet command we need a couple of additional headers.
89 * Behind the normal outhdr we put a segment with the scsi command
90 * block, and before the normal inhdr we put the sense data and the
91 * inhdr with additional status information.
93 if (type == cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_SCSI_CMD)) {
94 sg_init_one(&cmd, vbr->req->cmd, vbr->req->cmd_len);
95 sgs[num_out++] = &cmd;
99 if (vbr->out_hdr.type & cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_OUT))
100 sgs[num_out++] = data_sg;
102 sgs[num_out + num_in++] = data_sg;
105 if (type == cpu_to_virtio32(vq->vdev, VIRTIO_BLK_T_SCSI_CMD)) {
106 memcpy(vbr->sense, vbr->req->sense, SCSI_SENSE_BUFFERSIZE);
107 sg_init_one(&sense, vbr->sense, SCSI_SENSE_BUFFERSIZE);
108 sgs[num_out + num_in++] = &sense;
109 sg_init_one(&inhdr, &vbr->in_hdr, sizeof(vbr->in_hdr));
110 sgs[num_out + num_in++] = &inhdr;
113 sg_init_one(&status, &vbr->status, sizeof(vbr->status));
114 sgs[num_out + num_in++] = &status;
116 return virtqueue_add_sgs(vq, sgs, num_out, num_in, vbr, GFP_ATOMIC);
119 static inline void virtblk_request_done(struct request *req)
121 struct virtblk_req *vbr = blk_mq_rq_to_pdu(req);
122 struct virtio_blk *vblk = req->q->queuedata;
123 int error = virtblk_result(vbr);
125 if (req->cmd_type == REQ_TYPE_BLOCK_PC) {
126 req->resid_len = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.residual);
127 req->sense_len = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.sense_len);
128 req->errors = virtio32_to_cpu(vblk->vdev, vbr->in_hdr.errors);
129 } else if (req->cmd_type == REQ_TYPE_DRV_PRIV) {
130 req->errors = (error != 0);
133 blk_mq_end_request(req, error);
136 static void virtblk_done(struct virtqueue *vq)
138 struct virtio_blk *vblk = vq->vdev->priv;
139 bool req_done = false;
141 struct virtblk_req *vbr;
145 spin_lock_irqsave(&vblk->vqs[qid].lock, flags);
147 virtqueue_disable_cb(vq);
148 while ((vbr = virtqueue_get_buf(vblk->vqs[qid].vq, &len)) != NULL) {
149 blk_mq_complete_request(vbr->req, vbr->req->errors);
152 if (unlikely(virtqueue_is_broken(vq)))
154 } while (!virtqueue_enable_cb(vq));
156 /* In case queue is stopped waiting for more buffers. */
158 blk_mq_start_stopped_hw_queues(vblk->disk->queue, true);
159 spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags);
162 static int virtio_queue_rq(struct blk_mq_hw_ctx *hctx,
163 const struct blk_mq_queue_data *bd)
165 struct virtio_blk *vblk = hctx->queue->queuedata;
166 struct request *req = bd->rq;
167 struct virtblk_req *vbr = blk_mq_rq_to_pdu(req);
170 int qid = hctx->queue_num;
174 BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems);
177 if (req_op(req) == REQ_OP_FLUSH) {
178 vbr->out_hdr.type = cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_FLUSH);
179 vbr->out_hdr.sector = 0;
180 vbr->out_hdr.ioprio = cpu_to_virtio32(vblk->vdev, req_get_ioprio(vbr->req));
182 switch (req->cmd_type) {
184 vbr->out_hdr.type = 0;
185 vbr->out_hdr.sector = cpu_to_virtio64(vblk->vdev, blk_rq_pos(vbr->req));
186 vbr->out_hdr.ioprio = cpu_to_virtio32(vblk->vdev, req_get_ioprio(vbr->req));
188 case REQ_TYPE_BLOCK_PC:
189 vbr->out_hdr.type = cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_SCSI_CMD);
190 vbr->out_hdr.sector = 0;
191 vbr->out_hdr.ioprio = cpu_to_virtio32(vblk->vdev, req_get_ioprio(vbr->req));
193 case REQ_TYPE_DRV_PRIV:
194 vbr->out_hdr.type = cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_GET_ID);
195 vbr->out_hdr.sector = 0;
196 vbr->out_hdr.ioprio = cpu_to_virtio32(vblk->vdev, req_get_ioprio(vbr->req));
199 /* We don't put anything else in the queue. */
204 blk_mq_start_request(req);
206 num = blk_rq_map_sg(hctx->queue, vbr->req, vbr->sg);
208 if (rq_data_dir(vbr->req) == WRITE)
209 vbr->out_hdr.type |= cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_OUT);
211 vbr->out_hdr.type |= cpu_to_virtio32(vblk->vdev, VIRTIO_BLK_T_IN);
214 spin_lock_irqsave(&vblk->vqs[qid].lock, flags);
215 err = __virtblk_add_req(vblk->vqs[qid].vq, vbr, vbr->sg, num);
217 virtqueue_kick(vblk->vqs[qid].vq);
218 blk_mq_stop_hw_queue(hctx);
219 spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags);
220 /* Out of mem doesn't actually happen, since we fall back
221 * to direct descriptors */
222 if (err == -ENOMEM || err == -ENOSPC)
223 return BLK_MQ_RQ_QUEUE_BUSY;
224 return BLK_MQ_RQ_QUEUE_ERROR;
227 if (bd->last && virtqueue_kick_prepare(vblk->vqs[qid].vq))
229 spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags);
232 virtqueue_notify(vblk->vqs[qid].vq);
233 return BLK_MQ_RQ_QUEUE_OK;
236 /* return id (s/n) string for *disk to *id_str
238 static int virtblk_get_id(struct gendisk *disk, char *id_str)
240 struct virtio_blk *vblk = disk->private_data;
241 struct request_queue *q = vblk->disk->queue;
245 req = blk_get_request(q, READ, GFP_KERNEL);
248 req->cmd_type = REQ_TYPE_DRV_PRIV;
250 err = blk_rq_map_kern(q, req, id_str, VIRTIO_BLK_ID_BYTES, GFP_KERNEL);
254 err = blk_execute_rq(vblk->disk->queue, vblk->disk, req, false);
256 blk_put_request(req);
260 static int virtblk_ioctl(struct block_device *bdev, fmode_t mode,
261 unsigned int cmd, unsigned long data)
263 struct gendisk *disk = bdev->bd_disk;
264 struct virtio_blk *vblk = disk->private_data;
267 * Only allow the generic SCSI ioctls if the host can support it.
269 if (!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_SCSI))
272 return scsi_cmd_blk_ioctl(bdev, mode, cmd,
273 (void __user *)data);
276 /* We provide getgeo only to please some old bootloader/partitioning tools */
277 static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo)
279 struct virtio_blk *vblk = bd->bd_disk->private_data;
281 /* see if the host passed in geometry config */
282 if (virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_GEOMETRY)) {
283 virtio_cread(vblk->vdev, struct virtio_blk_config,
284 geometry.cylinders, &geo->cylinders);
285 virtio_cread(vblk->vdev, struct virtio_blk_config,
286 geometry.heads, &geo->heads);
287 virtio_cread(vblk->vdev, struct virtio_blk_config,
288 geometry.sectors, &geo->sectors);
290 /* some standard values, similar to sd */
292 geo->sectors = 1 << 5;
293 geo->cylinders = get_capacity(bd->bd_disk) >> 11;
298 static const struct block_device_operations virtblk_fops = {
299 .ioctl = virtblk_ioctl,
300 .owner = THIS_MODULE,
301 .getgeo = virtblk_getgeo,
304 static int index_to_minor(int index)
306 return index << PART_BITS;
309 static int minor_to_index(int minor)
311 return minor >> PART_BITS;
314 static ssize_t virtblk_serial_show(struct device *dev,
315 struct device_attribute *attr, char *buf)
317 struct gendisk *disk = dev_to_disk(dev);
320 /* sysfs gives us a PAGE_SIZE buffer */
321 BUILD_BUG_ON(PAGE_SIZE < VIRTIO_BLK_ID_BYTES);
323 buf[VIRTIO_BLK_ID_BYTES] = '\0';
324 err = virtblk_get_id(disk, buf);
328 if (err == -EIO) /* Unsupported? Make it empty. */
334 static DEVICE_ATTR(serial, S_IRUGO, virtblk_serial_show, NULL);
336 static void virtblk_config_changed_work(struct work_struct *work)
338 struct virtio_blk *vblk =
339 container_of(work, struct virtio_blk, config_work);
340 struct virtio_device *vdev = vblk->vdev;
341 struct request_queue *q = vblk->disk->queue;
342 char cap_str_2[10], cap_str_10[10];
343 char *envp[] = { "RESIZE=1", NULL };
346 /* Host must always specify the capacity. */
347 virtio_cread(vdev, struct virtio_blk_config, capacity, &capacity);
349 /* If capacity is too big, truncate with warning. */
350 if ((sector_t)capacity != capacity) {
351 dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n",
352 (unsigned long long)capacity);
353 capacity = (sector_t)-1;
356 string_get_size(capacity, queue_logical_block_size(q),
357 STRING_UNITS_2, cap_str_2, sizeof(cap_str_2));
358 string_get_size(capacity, queue_logical_block_size(q),
359 STRING_UNITS_10, cap_str_10, sizeof(cap_str_10));
361 dev_notice(&vdev->dev,
362 "new size: %llu %d-byte logical blocks (%s/%s)\n",
363 (unsigned long long)capacity,
364 queue_logical_block_size(q),
365 cap_str_10, cap_str_2);
367 set_capacity(vblk->disk, capacity);
368 revalidate_disk(vblk->disk);
369 kobject_uevent_env(&disk_to_dev(vblk->disk)->kobj, KOBJ_CHANGE, envp);
372 static void virtblk_config_changed(struct virtio_device *vdev)
374 struct virtio_blk *vblk = vdev->priv;
376 queue_work(virtblk_wq, &vblk->config_work);
379 static int init_vq(struct virtio_blk *vblk)
383 vq_callback_t **callbacks;
385 struct virtqueue **vqs;
386 unsigned short num_vqs;
387 struct virtio_device *vdev = vblk->vdev;
389 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_MQ,
390 struct virtio_blk_config, num_queues,
395 vblk->vqs = kmalloc_array(num_vqs, sizeof(*vblk->vqs), GFP_KERNEL);
399 names = kmalloc_array(num_vqs, sizeof(*names), GFP_KERNEL);
400 callbacks = kmalloc_array(num_vqs, sizeof(*callbacks), GFP_KERNEL);
401 vqs = kmalloc_array(num_vqs, sizeof(*vqs), GFP_KERNEL);
402 if (!names || !callbacks || !vqs) {
407 for (i = 0; i < num_vqs; i++) {
408 callbacks[i] = virtblk_done;
409 snprintf(vblk->vqs[i].name, VQ_NAME_LEN, "req.%d", i);
410 names[i] = vblk->vqs[i].name;
413 /* Discover virtqueues and write information to configuration. */
414 err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names,
419 for (i = 0; i < num_vqs; i++) {
420 spin_lock_init(&vblk->vqs[i].lock);
421 vblk->vqs[i].vq = vqs[i];
423 vblk->num_vqs = num_vqs;
435 * Legacy naming scheme used for virtio devices. We are stuck with it for
436 * virtio blk but don't ever use it for any new driver.
438 static int virtblk_name_format(char *prefix, int index, char *buf, int buflen)
440 const int base = 'z' - 'a' + 1;
441 char *begin = buf + strlen(prefix);
442 char *end = buf + buflen;
452 *--p = 'a' + (index % unit);
453 index = (index / unit) - 1;
454 } while (index >= 0);
456 memmove(begin, p, end - p);
457 memcpy(buf, prefix, strlen(prefix));
462 static int virtblk_get_cache_mode(struct virtio_device *vdev)
467 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE,
468 struct virtio_blk_config, wce,
472 * If WCE is not configurable and flush is not available,
473 * assume no writeback cache is in use.
476 writeback = virtio_has_feature(vdev, VIRTIO_BLK_F_FLUSH);
481 static void virtblk_update_cache_mode(struct virtio_device *vdev)
483 u8 writeback = virtblk_get_cache_mode(vdev);
484 struct virtio_blk *vblk = vdev->priv;
486 blk_queue_write_cache(vblk->disk->queue, writeback, false);
487 revalidate_disk(vblk->disk);
490 static const char *const virtblk_cache_types[] = {
491 "write through", "write back"
495 virtblk_cache_type_store(struct device *dev, struct device_attribute *attr,
496 const char *buf, size_t count)
498 struct gendisk *disk = dev_to_disk(dev);
499 struct virtio_blk *vblk = disk->private_data;
500 struct virtio_device *vdev = vblk->vdev;
503 BUG_ON(!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_CONFIG_WCE));
504 for (i = ARRAY_SIZE(virtblk_cache_types); --i >= 0; )
505 if (sysfs_streq(buf, virtblk_cache_types[i]))
511 virtio_cwrite8(vdev, offsetof(struct virtio_blk_config, wce), i);
512 virtblk_update_cache_mode(vdev);
517 virtblk_cache_type_show(struct device *dev, struct device_attribute *attr,
520 struct gendisk *disk = dev_to_disk(dev);
521 struct virtio_blk *vblk = disk->private_data;
522 u8 writeback = virtblk_get_cache_mode(vblk->vdev);
524 BUG_ON(writeback >= ARRAY_SIZE(virtblk_cache_types));
525 return snprintf(buf, 40, "%s\n", virtblk_cache_types[writeback]);
528 static const struct device_attribute dev_attr_cache_type_ro =
529 __ATTR(cache_type, S_IRUGO,
530 virtblk_cache_type_show, NULL);
531 static const struct device_attribute dev_attr_cache_type_rw =
532 __ATTR(cache_type, S_IRUGO|S_IWUSR,
533 virtblk_cache_type_show, virtblk_cache_type_store);
535 static int virtblk_init_request(void *data, struct request *rq,
536 unsigned int hctx_idx, unsigned int request_idx,
537 unsigned int numa_node)
539 struct virtio_blk *vblk = data;
540 struct virtblk_req *vbr = blk_mq_rq_to_pdu(rq);
542 sg_init_table(vbr->sg, vblk->sg_elems);
546 static struct blk_mq_ops virtio_mq_ops = {
547 .queue_rq = virtio_queue_rq,
548 .complete = virtblk_request_done,
549 .init_request = virtblk_init_request,
552 static unsigned int virtblk_queue_depth;
553 module_param_named(queue_depth, virtblk_queue_depth, uint, 0444);
555 static int virtblk_probe(struct virtio_device *vdev)
557 struct virtio_blk *vblk;
558 struct request_queue *q;
562 u32 v, blk_size, sg_elems, opt_io_size;
564 u8 physical_block_exp, alignment_offset;
566 if (!vdev->config->get) {
567 dev_err(&vdev->dev, "%s failure: config access disabled\n",
572 err = ida_simple_get(&vd_index_ida, 0, minor_to_index(1 << MINORBITS),
578 /* We need to know how many segments before we allocate. */
579 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_SEG_MAX,
580 struct virtio_blk_config, seg_max,
583 /* We need at least one SG element, whatever they say. */
584 if (err || !sg_elems)
587 /* We need an extra sg elements at head and tail. */
589 vdev->priv = vblk = kmalloc(sizeof(*vblk), GFP_KERNEL);
596 vblk->sg_elems = sg_elems;
598 INIT_WORK(&vblk->config_work, virtblk_config_changed_work);
604 /* FIXME: How many partitions? How long is a piece of string? */
605 vblk->disk = alloc_disk(1 << PART_BITS);
611 /* Default queue sizing is to fill the ring. */
612 if (!virtblk_queue_depth) {
613 virtblk_queue_depth = vblk->vqs[0].vq->num_free;
614 /* ... but without indirect descs, we use 2 descs per req */
615 if (!virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC))
616 virtblk_queue_depth /= 2;
619 memset(&vblk->tag_set, 0, sizeof(vblk->tag_set));
620 vblk->tag_set.ops = &virtio_mq_ops;
621 vblk->tag_set.queue_depth = virtblk_queue_depth;
622 vblk->tag_set.numa_node = NUMA_NO_NODE;
623 vblk->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
624 vblk->tag_set.cmd_size =
625 sizeof(struct virtblk_req) +
626 sizeof(struct scatterlist) * sg_elems;
627 vblk->tag_set.driver_data = vblk;
628 vblk->tag_set.nr_hw_queues = vblk->num_vqs;
630 err = blk_mq_alloc_tag_set(&vblk->tag_set);
634 q = blk_mq_init_queue(&vblk->tag_set);
639 vblk->disk->queue = q;
643 virtblk_name_format("vd", index, vblk->disk->disk_name, DISK_NAME_LEN);
645 vblk->disk->major = major;
646 vblk->disk->first_minor = index_to_minor(index);
647 vblk->disk->private_data = vblk;
648 vblk->disk->fops = &virtblk_fops;
649 vblk->disk->flags |= GENHD_FL_EXT_DEVT;
652 /* configure queue flush support */
653 virtblk_update_cache_mode(vdev);
655 /* If disk is read-only in the host, the guest should obey */
656 if (virtio_has_feature(vdev, VIRTIO_BLK_F_RO))
657 set_disk_ro(vblk->disk, 1);
659 /* Host must always specify the capacity. */
660 virtio_cread(vdev, struct virtio_blk_config, capacity, &cap);
662 /* If capacity is too big, truncate with warning. */
663 if ((sector_t)cap != cap) {
664 dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n",
665 (unsigned long long)cap);
668 set_capacity(vblk->disk, cap);
670 /* We can handle whatever the host told us to handle. */
671 blk_queue_max_segments(q, vblk->sg_elems-2);
673 /* No need to bounce any requests */
674 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
676 /* No real sector limit. */
677 blk_queue_max_hw_sectors(q, -1U);
679 /* Host can optionally specify maximum segment size and number of
681 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_SIZE_MAX,
682 struct virtio_blk_config, size_max, &v);
684 blk_queue_max_segment_size(q, v);
686 blk_queue_max_segment_size(q, -1U);
688 /* Host can optionally specify the block size of the device */
689 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_BLK_SIZE,
690 struct virtio_blk_config, blk_size,
693 blk_queue_logical_block_size(q, blk_size);
695 blk_size = queue_logical_block_size(q);
697 /* Use topology information if available */
698 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY,
699 struct virtio_blk_config, physical_block_exp,
700 &physical_block_exp);
701 if (!err && physical_block_exp)
702 blk_queue_physical_block_size(q,
703 blk_size * (1 << physical_block_exp));
705 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY,
706 struct virtio_blk_config, alignment_offset,
708 if (!err && alignment_offset)
709 blk_queue_alignment_offset(q, blk_size * alignment_offset);
711 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY,
712 struct virtio_blk_config, min_io_size,
714 if (!err && min_io_size)
715 blk_queue_io_min(q, blk_size * min_io_size);
717 err = virtio_cread_feature(vdev, VIRTIO_BLK_F_TOPOLOGY,
718 struct virtio_blk_config, opt_io_size,
720 if (!err && opt_io_size)
721 blk_queue_io_opt(q, blk_size * opt_io_size);
723 virtio_device_ready(vdev);
725 device_add_disk(&vdev->dev, vblk->disk);
726 err = device_create_file(disk_to_dev(vblk->disk), &dev_attr_serial);
730 if (virtio_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE))
731 err = device_create_file(disk_to_dev(vblk->disk),
732 &dev_attr_cache_type_rw);
734 err = device_create_file(disk_to_dev(vblk->disk),
735 &dev_attr_cache_type_ro);
741 del_gendisk(vblk->disk);
742 blk_cleanup_queue(vblk->disk->queue);
744 blk_mq_free_tag_set(&vblk->tag_set);
746 put_disk(vblk->disk);
748 vdev->config->del_vqs(vdev);
752 ida_simple_remove(&vd_index_ida, index);
757 static void virtblk_remove(struct virtio_device *vdev)
759 struct virtio_blk *vblk = vdev->priv;
760 int index = vblk->index;
763 /* Make sure no work handler is accessing the device. */
764 flush_work(&vblk->config_work);
766 del_gendisk(vblk->disk);
767 blk_cleanup_queue(vblk->disk->queue);
769 blk_mq_free_tag_set(&vblk->tag_set);
771 /* Stop all the virtqueues. */
772 vdev->config->reset(vdev);
774 refc = atomic_read(&disk_to_dev(vblk->disk)->kobj.kref.refcount);
775 put_disk(vblk->disk);
776 vdev->config->del_vqs(vdev);
780 /* Only free device id if we don't have any users */
782 ida_simple_remove(&vd_index_ida, index);
785 #ifdef CONFIG_PM_SLEEP
786 static int virtblk_freeze(struct virtio_device *vdev)
788 struct virtio_blk *vblk = vdev->priv;
790 /* Ensure we don't receive any more interrupts */
791 vdev->config->reset(vdev);
793 /* Make sure no work handler is accessing the device. */
794 flush_work(&vblk->config_work);
796 blk_mq_stop_hw_queues(vblk->disk->queue);
798 vdev->config->del_vqs(vdev);
802 static int virtblk_restore(struct virtio_device *vdev)
804 struct virtio_blk *vblk = vdev->priv;
807 ret = init_vq(vdev->priv);
811 virtio_device_ready(vdev);
813 blk_mq_start_stopped_hw_queues(vblk->disk->queue, true);
818 static const struct virtio_device_id id_table[] = {
819 { VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID },
823 static unsigned int features_legacy[] = {
824 VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY,
825 VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, VIRTIO_BLK_F_SCSI,
826 VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_TOPOLOGY, VIRTIO_BLK_F_CONFIG_WCE,
830 static unsigned int features[] = {
831 VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY,
832 VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE,
833 VIRTIO_BLK_F_FLUSH, VIRTIO_BLK_F_TOPOLOGY, VIRTIO_BLK_F_CONFIG_WCE,
837 static struct virtio_driver virtio_blk = {
838 .feature_table = features,
839 .feature_table_size = ARRAY_SIZE(features),
840 .feature_table_legacy = features_legacy,
841 .feature_table_size_legacy = ARRAY_SIZE(features_legacy),
842 .driver.name = KBUILD_MODNAME,
843 .driver.owner = THIS_MODULE,
844 .id_table = id_table,
845 .probe = virtblk_probe,
846 .remove = virtblk_remove,
847 .config_changed = virtblk_config_changed,
848 #ifdef CONFIG_PM_SLEEP
849 .freeze = virtblk_freeze,
850 .restore = virtblk_restore,
854 static int __init init(void)
858 virtblk_wq = alloc_workqueue("virtio-blk", 0, 0);
862 major = register_blkdev(0, "virtblk");
865 goto out_destroy_workqueue;
868 error = register_virtio_driver(&virtio_blk);
870 goto out_unregister_blkdev;
873 out_unregister_blkdev:
874 unregister_blkdev(major, "virtblk");
875 out_destroy_workqueue:
876 destroy_workqueue(virtblk_wq);
880 static void __exit fini(void)
882 unregister_virtio_driver(&virtio_blk);
883 unregister_blkdev(major, "virtblk");
884 destroy_workqueue(virtblk_wq);
889 MODULE_DEVICE_TABLE(virtio, id_table);
890 MODULE_DESCRIPTION("Virtio block driver");
891 MODULE_LICENSE("GPL");