raspi/linux
1
0
Fork 1
mirror of https://github.com/raspberrypi/linux.git synced 2025-12-06 01:49:46 +00:00
Code Issues Projects Releases Wiki Activity

virtio-blk: Don't use MAX_DISCARD_SEGMENTS if max_discard_seg is zero

Browse Source 
[ Upstream commit dacc73ed0b ]

Currently the value of max_discard_segment will be set to
MAX_DISCARD_SEGMENTS (256) with no basis in hardware if device
set 0 to max_discard_seg in configuration space. It's incorrect
since the device might not be able to handle such large descriptors.
To fix it, let's follow max_segments restrictions in this case.

Fixes: 1f23816b8e ("virtio_blk: add discard and write zeroes support")
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: https://lore.kernel.org/r/20220304100058.116-1-xieyongji@bytedance.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Xie Yongji
2022-03-04 18:00:57 +08:00
committed by Greg Kroah-Hartman
parent a3d5fcc6cf
commit cca9d5035b
1 changed files with 8 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
drivers/block/virtio_blk.c
View File

@@ -869,9 +869,15 @@ static int virtblk_probe(struct virtio_device *vdev)
virtio_cread(vdev, struct virtio_blk_config, max_discard_seg, virtio_cread(vdev, struct virtio_blk_config, max_discard_seg,
&v); &v);
/*
* max_discard_seg == 0 is out of spec but we always
* handled it.
*/
if (!v)
v = sg_elems - 2;
blk_queue_max_discard_segments(q, blk_queue_max_discard_segments(q,
min_not_zero(v, min(v, MAX_DISCARD_SEGMENTS));
MAX_DISCARD_SEGMENTS));
blk_queue_flag_set(QUEUE_FLAG_DISCARD, q); blk_queue_flag_set(QUEUE_FLAG_DISCARD, q);
} }