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>
18 module_param(use_bio, bool, S_IRUGO);
21 static DEFINE_IDA(vd_index_ida);
23 struct workqueue_struct *virtblk_wq;
27 struct virtio_device *vdev;
29 wait_queue_head_t queue_wait;
31 /* The disk structure for the kernel. */
36 /* Process context for config space updates */
37 struct work_struct config_work;
39 /* Lock for config space updates */
40 struct mutex config_lock;
42 /* enable config space updates */
45 /* What host tells us, plus 2 for header & tailer. */
46 unsigned int sg_elems;
48 /* Ida index - used to track minor number allocations. */
51 /* Scatterlist: can be too big for stack. */
52 struct scatterlist sg[/*sg_elems*/];
59 struct virtio_blk_outhdr out_hdr;
60 struct virtio_scsi_inhdr in_hdr;
61 struct work_struct work;
62 struct virtio_blk *vblk;
65 struct scatterlist sg[];
75 static inline int virtblk_result(struct virtblk_req *vbr)
77 switch (vbr->status) {
80 case VIRTIO_BLK_S_UNSUPP:
87 static inline struct virtblk_req *virtblk_alloc_req(struct virtio_blk *vblk,
90 struct virtblk_req *vbr;
92 vbr = mempool_alloc(vblk->pool, gfp_mask);
98 sg_init_table(vbr->sg, vblk->sg_elems);
103 static void virtblk_add_buf_wait(struct virtio_blk *vblk,
104 struct virtblk_req *vbr,
111 prepare_to_wait_exclusive(&vblk->queue_wait, &wait,
112 TASK_UNINTERRUPTIBLE);
114 spin_lock_irq(vblk->disk->queue->queue_lock);
115 if (virtqueue_add_buf(vblk->vq, vbr->sg, out, in, vbr,
117 spin_unlock_irq(vblk->disk->queue->queue_lock);
120 virtqueue_kick(vblk->vq);
121 spin_unlock_irq(vblk->disk->queue->queue_lock);
127 finish_wait(&vblk->queue_wait, &wait);
130 static inline void virtblk_add_req(struct virtblk_req *vbr,
131 unsigned int out, unsigned int in)
133 struct virtio_blk *vblk = vbr->vblk;
135 spin_lock_irq(vblk->disk->queue->queue_lock);
136 if (unlikely(virtqueue_add_buf(vblk->vq, vbr->sg, out, in, vbr,
138 spin_unlock_irq(vblk->disk->queue->queue_lock);
139 virtblk_add_buf_wait(vblk, vbr, out, in);
142 virtqueue_kick(vblk->vq);
143 spin_unlock_irq(vblk->disk->queue->queue_lock);
146 static int virtblk_bio_send_flush(struct virtblk_req *vbr)
148 unsigned int out = 0, in = 0;
150 vbr->flags |= VBLK_IS_FLUSH;
151 vbr->out_hdr.type = VIRTIO_BLK_T_FLUSH;
152 vbr->out_hdr.sector = 0;
153 vbr->out_hdr.ioprio = 0;
154 sg_set_buf(&vbr->sg[out++], &vbr->out_hdr, sizeof(vbr->out_hdr));
155 sg_set_buf(&vbr->sg[out + in++], &vbr->status, sizeof(vbr->status));
157 virtblk_add_req(vbr, out, in);
162 static int virtblk_bio_send_data(struct virtblk_req *vbr)
164 struct virtio_blk *vblk = vbr->vblk;
165 unsigned int num, out = 0, in = 0;
166 struct bio *bio = vbr->bio;
168 vbr->flags &= ~VBLK_IS_FLUSH;
169 vbr->out_hdr.type = 0;
170 vbr->out_hdr.sector = bio->bi_sector;
171 vbr->out_hdr.ioprio = bio_prio(bio);
173 sg_set_buf(&vbr->sg[out++], &vbr->out_hdr, sizeof(vbr->out_hdr));
175 num = blk_bio_map_sg(vblk->disk->queue, bio, vbr->sg + out);
177 sg_set_buf(&vbr->sg[num + out + in++], &vbr->status,
178 sizeof(vbr->status));
181 if (bio->bi_rw & REQ_WRITE) {
182 vbr->out_hdr.type |= VIRTIO_BLK_T_OUT;
185 vbr->out_hdr.type |= VIRTIO_BLK_T_IN;
190 virtblk_add_req(vbr, out, in);
195 static void virtblk_bio_send_data_work(struct work_struct *work)
197 struct virtblk_req *vbr;
199 vbr = container_of(work, struct virtblk_req, work);
201 virtblk_bio_send_data(vbr);
204 static void virtblk_bio_send_flush_work(struct work_struct *work)
206 struct virtblk_req *vbr;
208 vbr = container_of(work, struct virtblk_req, work);
210 virtblk_bio_send_flush(vbr);
213 static inline void virtblk_request_done(struct virtblk_req *vbr)
215 struct virtio_blk *vblk = vbr->vblk;
216 struct request *req = vbr->req;
217 int error = virtblk_result(vbr);
219 if (req->cmd_type == REQ_TYPE_BLOCK_PC) {
220 req->resid_len = vbr->in_hdr.residual;
221 req->sense_len = vbr->in_hdr.sense_len;
222 req->errors = vbr->in_hdr.errors;
223 } else if (req->cmd_type == REQ_TYPE_SPECIAL) {
224 req->errors = (error != 0);
227 __blk_end_request_all(req, error);
228 mempool_free(vbr, vblk->pool);
231 static inline void virtblk_bio_flush_done(struct virtblk_req *vbr)
233 struct virtio_blk *vblk = vbr->vblk;
235 if (vbr->flags & VBLK_REQ_DATA) {
236 /* Send out the actual write data */
237 INIT_WORK(&vbr->work, virtblk_bio_send_data_work);
238 queue_work(virtblk_wq, &vbr->work);
240 bio_endio(vbr->bio, virtblk_result(vbr));
241 mempool_free(vbr, vblk->pool);
245 static inline void virtblk_bio_data_done(struct virtblk_req *vbr)
247 struct virtio_blk *vblk = vbr->vblk;
249 if (unlikely(vbr->flags & VBLK_REQ_FUA)) {
250 /* Send out a flush before end the bio */
251 vbr->flags &= ~VBLK_REQ_DATA;
252 INIT_WORK(&vbr->work, virtblk_bio_send_flush_work);
253 queue_work(virtblk_wq, &vbr->work);
255 bio_endio(vbr->bio, virtblk_result(vbr));
256 mempool_free(vbr, vblk->pool);
260 static inline void virtblk_bio_done(struct virtblk_req *vbr)
262 if (unlikely(vbr->flags & VBLK_IS_FLUSH))
263 virtblk_bio_flush_done(vbr);
265 virtblk_bio_data_done(vbr);
268 static void virtblk_done(struct virtqueue *vq)
270 struct virtio_blk *vblk = vq->vdev->priv;
271 bool bio_done = false, req_done = false;
272 struct virtblk_req *vbr;
276 spin_lock_irqsave(vblk->disk->queue->queue_lock, flags);
278 virtqueue_disable_cb(vq);
279 while ((vbr = virtqueue_get_buf(vblk->vq, &len)) != NULL) {
281 virtblk_bio_done(vbr);
284 virtblk_request_done(vbr);
288 } while (!virtqueue_enable_cb(vq));
289 /* In case queue is stopped waiting for more buffers. */
291 blk_start_queue(vblk->disk->queue);
292 spin_unlock_irqrestore(vblk->disk->queue->queue_lock, flags);
295 wake_up(&vblk->queue_wait);
298 static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
301 unsigned long num, out = 0, in = 0;
302 struct virtblk_req *vbr;
304 vbr = virtblk_alloc_req(vblk, GFP_ATOMIC);
306 /* When another request finishes we'll try again. */
311 if (req->cmd_flags & REQ_FLUSH) {
312 vbr->out_hdr.type = VIRTIO_BLK_T_FLUSH;
313 vbr->out_hdr.sector = 0;
314 vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
316 switch (req->cmd_type) {
318 vbr->out_hdr.type = 0;
319 vbr->out_hdr.sector = blk_rq_pos(vbr->req);
320 vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
322 case REQ_TYPE_BLOCK_PC:
323 vbr->out_hdr.type = VIRTIO_BLK_T_SCSI_CMD;
324 vbr->out_hdr.sector = 0;
325 vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
327 case REQ_TYPE_SPECIAL:
328 vbr->out_hdr.type = VIRTIO_BLK_T_GET_ID;
329 vbr->out_hdr.sector = 0;
330 vbr->out_hdr.ioprio = req_get_ioprio(vbr->req);
333 /* We don't put anything else in the queue. */
338 sg_set_buf(&vblk->sg[out++], &vbr->out_hdr, sizeof(vbr->out_hdr));
341 * If this is a packet command we need a couple of additional headers.
342 * Behind the normal outhdr we put a segment with the scsi command
343 * block, and before the normal inhdr we put the sense data and the
344 * inhdr with additional status information before the normal inhdr.
346 if (vbr->req->cmd_type == REQ_TYPE_BLOCK_PC)
347 sg_set_buf(&vblk->sg[out++], vbr->req->cmd, vbr->req->cmd_len);
349 num = blk_rq_map_sg(q, vbr->req, vblk->sg + out);
351 if (vbr->req->cmd_type == REQ_TYPE_BLOCK_PC) {
352 sg_set_buf(&vblk->sg[num + out + in++], vbr->req->sense, SCSI_SENSE_BUFFERSIZE);
353 sg_set_buf(&vblk->sg[num + out + in++], &vbr->in_hdr,
354 sizeof(vbr->in_hdr));
357 sg_set_buf(&vblk->sg[num + out + in++], &vbr->status,
358 sizeof(vbr->status));
361 if (rq_data_dir(vbr->req) == WRITE) {
362 vbr->out_hdr.type |= VIRTIO_BLK_T_OUT;
365 vbr->out_hdr.type |= VIRTIO_BLK_T_IN;
370 if (virtqueue_add_buf(vblk->vq, vblk->sg, out, in, vbr,
372 mempool_free(vbr, vblk->pool);
379 static void virtblk_request(struct request_queue *q)
381 struct virtio_blk *vblk = q->queuedata;
383 unsigned int issued = 0;
385 while ((req = blk_peek_request(q)) != NULL) {
386 BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems);
388 /* If this request fails, stop queue and wait for something to
389 finish to restart it. */
390 if (!do_req(q, vblk, req)) {
394 blk_start_request(req);
399 virtqueue_kick(vblk->vq);
402 static void virtblk_make_request(struct request_queue *q, struct bio *bio)
404 struct virtio_blk *vblk = q->queuedata;
405 struct virtblk_req *vbr;
407 BUG_ON(bio->bi_phys_segments + 2 > vblk->sg_elems);
409 vbr = virtblk_alloc_req(vblk, GFP_NOIO);
411 bio_endio(bio, -ENOMEM);
417 if (bio->bi_rw & REQ_FLUSH)
418 vbr->flags |= VBLK_REQ_FLUSH;
419 if (bio->bi_rw & REQ_FUA)
420 vbr->flags |= VBLK_REQ_FUA;
422 vbr->flags |= VBLK_REQ_DATA;
424 if (unlikely(vbr->flags & VBLK_REQ_FLUSH))
425 virtblk_bio_send_flush(vbr);
427 virtblk_bio_send_data(vbr);
430 /* return id (s/n) string for *disk to *id_str
432 static int virtblk_get_id(struct gendisk *disk, char *id_str)
434 struct virtio_blk *vblk = disk->private_data;
439 bio = bio_map_kern(vblk->disk->queue, id_str, VIRTIO_BLK_ID_BYTES,
444 req = blk_make_request(vblk->disk->queue, bio, GFP_KERNEL);
450 req->cmd_type = REQ_TYPE_SPECIAL;
451 err = blk_execute_rq(vblk->disk->queue, vblk->disk, req, false);
452 blk_put_request(req);
457 static int virtblk_ioctl(struct block_device *bdev, fmode_t mode,
458 unsigned int cmd, unsigned long data)
460 struct gendisk *disk = bdev->bd_disk;
461 struct virtio_blk *vblk = disk->private_data;
464 * Only allow the generic SCSI ioctls if the host can support it.
466 if (!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_SCSI))
469 return scsi_cmd_blk_ioctl(bdev, mode, cmd,
470 (void __user *)data);
473 /* We provide getgeo only to please some old bootloader/partitioning tools */
474 static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo)
476 struct virtio_blk *vblk = bd->bd_disk->private_data;
477 struct virtio_blk_geometry vgeo;
480 /* see if the host passed in geometry config */
481 err = virtio_config_val(vblk->vdev, VIRTIO_BLK_F_GEOMETRY,
482 offsetof(struct virtio_blk_config, geometry),
486 geo->heads = vgeo.heads;
487 geo->sectors = vgeo.sectors;
488 geo->cylinders = vgeo.cylinders;
490 /* some standard values, similar to sd */
492 geo->sectors = 1 << 5;
493 geo->cylinders = get_capacity(bd->bd_disk) >> 11;
498 static const struct block_device_operations virtblk_fops = {
499 .ioctl = virtblk_ioctl,
500 .owner = THIS_MODULE,
501 .getgeo = virtblk_getgeo,
504 static int index_to_minor(int index)
506 return index << PART_BITS;
509 static int minor_to_index(int minor)
511 return minor >> PART_BITS;
514 static ssize_t virtblk_serial_show(struct device *dev,
515 struct device_attribute *attr, char *buf)
517 struct gendisk *disk = dev_to_disk(dev);
520 /* sysfs gives us a PAGE_SIZE buffer */
521 BUILD_BUG_ON(PAGE_SIZE < VIRTIO_BLK_ID_BYTES);
523 buf[VIRTIO_BLK_ID_BYTES] = '\0';
524 err = virtblk_get_id(disk, buf);
528 if (err == -EIO) /* Unsupported? Make it empty. */
533 DEVICE_ATTR(serial, S_IRUGO, virtblk_serial_show, NULL);
535 static void virtblk_config_changed_work(struct work_struct *work)
537 struct virtio_blk *vblk =
538 container_of(work, struct virtio_blk, config_work);
539 struct virtio_device *vdev = vblk->vdev;
540 struct request_queue *q = vblk->disk->queue;
541 char cap_str_2[10], cap_str_10[10];
544 mutex_lock(&vblk->config_lock);
545 if (!vblk->config_enable)
548 /* Host must always specify the capacity. */
549 vdev->config->get(vdev, offsetof(struct virtio_blk_config, capacity),
550 &capacity, sizeof(capacity));
552 /* If capacity is too big, truncate with warning. */
553 if ((sector_t)capacity != capacity) {
554 dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n",
555 (unsigned long long)capacity);
556 capacity = (sector_t)-1;
559 size = capacity * queue_logical_block_size(q);
560 string_get_size(size, STRING_UNITS_2, cap_str_2, sizeof(cap_str_2));
561 string_get_size(size, STRING_UNITS_10, cap_str_10, sizeof(cap_str_10));
563 dev_notice(&vdev->dev,
564 "new size: %llu %d-byte logical blocks (%s/%s)\n",
565 (unsigned long long)capacity,
566 queue_logical_block_size(q),
567 cap_str_10, cap_str_2);
569 set_capacity(vblk->disk, capacity);
570 revalidate_disk(vblk->disk);
572 mutex_unlock(&vblk->config_lock);
575 static void virtblk_config_changed(struct virtio_device *vdev)
577 struct virtio_blk *vblk = vdev->priv;
579 queue_work(virtblk_wq, &vblk->config_work);
582 static int init_vq(struct virtio_blk *vblk)
586 /* We expect one virtqueue, for output. */
587 vblk->vq = virtio_find_single_vq(vblk->vdev, virtblk_done, "requests");
588 if (IS_ERR(vblk->vq))
589 err = PTR_ERR(vblk->vq);
595 * Legacy naming scheme used for virtio devices. We are stuck with it for
596 * virtio blk but don't ever use it for any new driver.
598 static int virtblk_name_format(char *prefix, int index, char *buf, int buflen)
600 const int base = 'z' - 'a' + 1;
601 char *begin = buf + strlen(prefix);
602 char *end = buf + buflen;
612 *--p = 'a' + (index % unit);
613 index = (index / unit) - 1;
614 } while (index >= 0);
616 memmove(begin, p, end - p);
617 memcpy(buf, prefix, strlen(prefix));
622 static int virtblk_get_cache_mode(struct virtio_device *vdev)
627 err = virtio_config_val(vdev, VIRTIO_BLK_F_CONFIG_WCE,
628 offsetof(struct virtio_blk_config, wce),
631 writeback = virtio_has_feature(vdev, VIRTIO_BLK_F_WCE);
636 static void virtblk_update_cache_mode(struct virtio_device *vdev)
638 u8 writeback = virtblk_get_cache_mode(vdev);
639 struct virtio_blk *vblk = vdev->priv;
642 blk_queue_flush(vblk->disk->queue, REQ_FLUSH);
644 blk_queue_flush(vblk->disk->queue, 0);
646 revalidate_disk(vblk->disk);
649 static const char *const virtblk_cache_types[] = {
650 "write through", "write back"
654 virtblk_cache_type_store(struct device *dev, struct device_attribute *attr,
655 const char *buf, size_t count)
657 struct gendisk *disk = dev_to_disk(dev);
658 struct virtio_blk *vblk = disk->private_data;
659 struct virtio_device *vdev = vblk->vdev;
663 BUG_ON(!virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_CONFIG_WCE));
664 for (i = ARRAY_SIZE(virtblk_cache_types); --i >= 0; )
665 if (sysfs_streq(buf, virtblk_cache_types[i]))
672 vdev->config->set(vdev,
673 offsetof(struct virtio_blk_config, wce),
674 &writeback, sizeof(writeback));
676 virtblk_update_cache_mode(vdev);
681 virtblk_cache_type_show(struct device *dev, struct device_attribute *attr,
684 struct gendisk *disk = dev_to_disk(dev);
685 struct virtio_blk *vblk = disk->private_data;
686 u8 writeback = virtblk_get_cache_mode(vblk->vdev);
688 BUG_ON(writeback >= ARRAY_SIZE(virtblk_cache_types));
689 return snprintf(buf, 40, "%s\n", virtblk_cache_types[writeback]);
692 static const struct device_attribute dev_attr_cache_type_ro =
693 __ATTR(cache_type, S_IRUGO,
694 virtblk_cache_type_show, NULL);
695 static const struct device_attribute dev_attr_cache_type_rw =
696 __ATTR(cache_type, S_IRUGO|S_IWUSR,
697 virtblk_cache_type_show, virtblk_cache_type_store);
699 static int virtblk_probe(struct virtio_device *vdev)
701 struct virtio_blk *vblk;
702 struct request_queue *q;
707 u32 v, blk_size, sg_elems, opt_io_size;
709 u8 physical_block_exp, alignment_offset;
711 err = ida_simple_get(&vd_index_ida, 0, minor_to_index(1 << MINORBITS),
717 /* We need to know how many segments before we allocate. */
718 err = virtio_config_val(vdev, VIRTIO_BLK_F_SEG_MAX,
719 offsetof(struct virtio_blk_config, seg_max),
722 /* We need at least one SG element, whatever they say. */
723 if (err || !sg_elems)
726 /* We need an extra sg elements at head and tail. */
728 vdev->priv = vblk = kmalloc(sizeof(*vblk) +
729 sizeof(vblk->sg[0]) * sg_elems, GFP_KERNEL);
735 init_waitqueue_head(&vblk->queue_wait);
737 vblk->sg_elems = sg_elems;
738 sg_init_table(vblk->sg, vblk->sg_elems);
739 mutex_init(&vblk->config_lock);
741 INIT_WORK(&vblk->config_work, virtblk_config_changed_work);
742 vblk->config_enable = true;
748 pool_size = sizeof(struct virtblk_req);
750 pool_size += sizeof(struct scatterlist) * sg_elems;
751 vblk->pool = mempool_create_kmalloc_pool(1, pool_size);
757 /* FIXME: How many partitions? How long is a piece of string? */
758 vblk->disk = alloc_disk(1 << PART_BITS);
764 q = vblk->disk->queue = blk_init_queue(virtblk_request, NULL);
771 blk_queue_make_request(q, virtblk_make_request);
774 virtblk_name_format("vd", index, vblk->disk->disk_name, DISK_NAME_LEN);
776 vblk->disk->major = major;
777 vblk->disk->first_minor = index_to_minor(index);
778 vblk->disk->private_data = vblk;
779 vblk->disk->fops = &virtblk_fops;
780 vblk->disk->driverfs_dev = &vdev->dev;
783 /* configure queue flush support */
784 virtblk_update_cache_mode(vdev);
786 /* If disk is read-only in the host, the guest should obey */
787 if (virtio_has_feature(vdev, VIRTIO_BLK_F_RO))
788 set_disk_ro(vblk->disk, 1);
790 /* Host must always specify the capacity. */
791 vdev->config->get(vdev, offsetof(struct virtio_blk_config, capacity),
794 /* If capacity is too big, truncate with warning. */
795 if ((sector_t)cap != cap) {
796 dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n",
797 (unsigned long long)cap);
800 set_capacity(vblk->disk, cap);
802 /* We can handle whatever the host told us to handle. */
803 blk_queue_max_segments(q, vblk->sg_elems-2);
805 /* No need to bounce any requests */
806 blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
808 /* No real sector limit. */
809 blk_queue_max_hw_sectors(q, -1U);
811 /* Host can optionally specify maximum segment size and number of
813 err = virtio_config_val(vdev, VIRTIO_BLK_F_SIZE_MAX,
814 offsetof(struct virtio_blk_config, size_max),
817 blk_queue_max_segment_size(q, v);
819 blk_queue_max_segment_size(q, -1U);
821 /* Host can optionally specify the block size of the device */
822 err = virtio_config_val(vdev, VIRTIO_BLK_F_BLK_SIZE,
823 offsetof(struct virtio_blk_config, blk_size),
826 blk_queue_logical_block_size(q, blk_size);
828 blk_size = queue_logical_block_size(q);
830 /* Use topology information if available */
831 err = virtio_config_val(vdev, VIRTIO_BLK_F_TOPOLOGY,
832 offsetof(struct virtio_blk_config, physical_block_exp),
833 &physical_block_exp);
834 if (!err && physical_block_exp)
835 blk_queue_physical_block_size(q,
836 blk_size * (1 << physical_block_exp));
838 err = virtio_config_val(vdev, VIRTIO_BLK_F_TOPOLOGY,
839 offsetof(struct virtio_blk_config, alignment_offset),
841 if (!err && alignment_offset)
842 blk_queue_alignment_offset(q, blk_size * alignment_offset);
844 err = virtio_config_val(vdev, VIRTIO_BLK_F_TOPOLOGY,
845 offsetof(struct virtio_blk_config, min_io_size),
847 if (!err && min_io_size)
848 blk_queue_io_min(q, blk_size * min_io_size);
850 err = virtio_config_val(vdev, VIRTIO_BLK_F_TOPOLOGY,
851 offsetof(struct virtio_blk_config, opt_io_size),
853 if (!err && opt_io_size)
854 blk_queue_io_opt(q, blk_size * opt_io_size);
856 add_disk(vblk->disk);
857 err = device_create_file(disk_to_dev(vblk->disk), &dev_attr_serial);
861 if (virtio_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE))
862 err = device_create_file(disk_to_dev(vblk->disk),
863 &dev_attr_cache_type_rw);
865 err = device_create_file(disk_to_dev(vblk->disk),
866 &dev_attr_cache_type_ro);
872 del_gendisk(vblk->disk);
873 blk_cleanup_queue(vblk->disk->queue);
875 put_disk(vblk->disk);
877 mempool_destroy(vblk->pool);
879 vdev->config->del_vqs(vdev);
883 ida_simple_remove(&vd_index_ida, index);
888 static void virtblk_remove(struct virtio_device *vdev)
890 struct virtio_blk *vblk = vdev->priv;
891 int index = vblk->index;
894 /* Prevent config work handler from accessing the device. */
895 mutex_lock(&vblk->config_lock);
896 vblk->config_enable = false;
897 mutex_unlock(&vblk->config_lock);
899 del_gendisk(vblk->disk);
900 blk_cleanup_queue(vblk->disk->queue);
902 /* Stop all the virtqueues. */
903 vdev->config->reset(vdev);
905 flush_work(&vblk->config_work);
907 refc = atomic_read(&disk_to_dev(vblk->disk)->kobj.kref.refcount);
908 put_disk(vblk->disk);
909 mempool_destroy(vblk->pool);
910 vdev->config->del_vqs(vdev);
913 /* Only free device id if we don't have any users */
915 ida_simple_remove(&vd_index_ida, index);
919 static int virtblk_freeze(struct virtio_device *vdev)
921 struct virtio_blk *vblk = vdev->priv;
923 /* Ensure we don't receive any more interrupts */
924 vdev->config->reset(vdev);
926 /* Prevent config work handler from accessing the device. */
927 mutex_lock(&vblk->config_lock);
928 vblk->config_enable = false;
929 mutex_unlock(&vblk->config_lock);
931 flush_work(&vblk->config_work);
933 spin_lock_irq(vblk->disk->queue->queue_lock);
934 blk_stop_queue(vblk->disk->queue);
935 spin_unlock_irq(vblk->disk->queue->queue_lock);
936 blk_sync_queue(vblk->disk->queue);
938 vdev->config->del_vqs(vdev);
942 static int virtblk_restore(struct virtio_device *vdev)
944 struct virtio_blk *vblk = vdev->priv;
947 vblk->config_enable = true;
948 ret = init_vq(vdev->priv);
950 spin_lock_irq(vblk->disk->queue->queue_lock);
951 blk_start_queue(vblk->disk->queue);
952 spin_unlock_irq(vblk->disk->queue->queue_lock);
958 static const struct virtio_device_id id_table[] = {
959 { VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID },
963 static unsigned int features[] = {
964 VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY,
965 VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, VIRTIO_BLK_F_SCSI,
966 VIRTIO_BLK_F_WCE, VIRTIO_BLK_F_TOPOLOGY, VIRTIO_BLK_F_CONFIG_WCE
969 static struct virtio_driver virtio_blk = {
970 .feature_table = features,
971 .feature_table_size = ARRAY_SIZE(features),
972 .driver.name = KBUILD_MODNAME,
973 .driver.owner = THIS_MODULE,
974 .id_table = id_table,
975 .probe = virtblk_probe,
976 .remove = virtblk_remove,
977 .config_changed = virtblk_config_changed,
979 .freeze = virtblk_freeze,
980 .restore = virtblk_restore,
984 static int __init init(void)
988 virtblk_wq = alloc_workqueue("virtio-blk", 0, 0);
992 major = register_blkdev(0, "virtblk");
995 goto out_destroy_workqueue;
998 error = register_virtio_driver(&virtio_blk);
1000 goto out_unregister_blkdev;
1003 out_unregister_blkdev:
1004 unregister_blkdev(major, "virtblk");
1005 out_destroy_workqueue:
1006 destroy_workqueue(virtblk_wq);
1010 static void __exit fini(void)
1012 unregister_blkdev(major, "virtblk");
1013 unregister_virtio_driver(&virtio_blk);
1014 destroy_workqueue(virtblk_wq);
1019 MODULE_DEVICE_TABLE(virtio, id_table);
1020 MODULE_DESCRIPTION("Virtio block driver");
1021 MODULE_LICENSE("GPL");