diff options
| author | Xie Yongji <xieyongji@bytedance.com> | 2022-03-04 13:00:58 +0300 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2022-03-06 14:06:50 +0300 |
| commit | e030759a1ddcbf61d42b6e996bfeb675e0032d8b (patch) | |
| tree | 70775c214722e94d19e491586189eccda4d12bdc /drivers/block | |
| parent | dacc73ed0b88f1a787ec20385f42ca9dd9eddcd0 (diff) | |
| download | linux-e030759a1ddcbf61d42b6e996bfeb675e0032d8b.tar.xz | |
virtio-blk: Remove BUG_ON() in virtio_queue_rq()
Currently we have a BUG_ON() to make sure the number of sg
list does not exceed queue_max_segments() in virtio_queue_rq().
However, the block layer uses queue_max_discard_segments()
instead of queue_max_segments() to limit the sg list for
discard requests. So the BUG_ON() might be triggered if
virtio-blk device reports a larger value for max discard
segment than queue_max_segments(). To fix it, let's simply
remove the BUG_ON() which has become unnecessary after commit
02746e26c39e("virtio-blk: avoid preallocating big SGL for data").
And the unused vblk->sg_elems can also be removed together.
Fixes: 1f23816b8eb8 ("virtio_blk: add discard and write zeroes support")
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Link: https://lore.kernel.org/r/20220304100058.116-2-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'drivers/block')
| -rw-r--r-- | drivers/block/virtio_blk.c | 12 |
1 files changed, 2 insertions, 10 deletions
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 7fc2c8b97077..8c415be86732 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -76,9 +76,6 @@ struct virtio_blk { */ refcount_t refs; - /* What host tells us, plus 2 for header & tailer. */ - unsigned int sg_elems; - /* Ida index - used to track minor number allocations. */ int index; @@ -322,8 +319,6 @@ static blk_status_t virtio_queue_rq(struct blk_mq_hw_ctx *hctx, blk_status_t status; int err; - BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems); - status = virtblk_setup_cmd(vblk->vdev, req, vbr); if (unlikely(status)) return status; @@ -783,8 +778,6 @@ static int virtblk_probe(struct virtio_device *vdev) /* Prevent integer overflows and honor max vq size */ sg_elems = min_t(u32, sg_elems, VIRTIO_BLK_MAX_SG_ELEMS - 2); - /* We need extra sg elements at head and tail. */ - sg_elems += 2; vdev->priv = vblk = kmalloc(sizeof(*vblk), GFP_KERNEL); if (!vblk) { err = -ENOMEM; @@ -796,7 +789,6 @@ static int virtblk_probe(struct virtio_device *vdev) mutex_init(&vblk->vdev_mutex); vblk->vdev = vdev; - vblk->sg_elems = sg_elems; INIT_WORK(&vblk->config_work, virtblk_config_changed_work); @@ -853,7 +845,7 @@ static int virtblk_probe(struct virtio_device *vdev) set_disk_ro(vblk->disk, 1); /* We can handle whatever the host told us to handle. */ - blk_queue_max_segments(q, vblk->sg_elems-2); + blk_queue_max_segments(q, sg_elems); /* No real sector limit. */ blk_queue_max_hw_sectors(q, -1U); @@ -931,7 +923,7 @@ static int virtblk_probe(struct virtio_device *vdev) * handled it. */ if (!v) - v = sg_elems - 2; + v = sg_elems; blk_queue_max_discard_segments(q, min(v, MAX_DISCARD_SEGMENTS)); |