On 2/22/21 2:48 AM, Jan Kara wrote:
> Commit 384d87ef2c95 ("block: Do not discard buffers under a mounted
> filesystem") made paths issuing discard or zeroout requests to the
> underlying device try to grab block device in exclusive mode. If that
> failed we returned EBUSY to userspace. This however caused unexpected
> fallout in userspace where e.g. FUSE filesystems issue discard requests
> from userspace daemons although the device is open exclusively by the
> kernel. Also shrinking of logical volume by LVM issues discard requests
> to a device which may be claimed exclusively because there's another LV
> on the same PV. So to avoid these userspace regressions, fall back to
> invalidate_inode_pages2_range() instead of returning EBUSY to userspace
> and return EBUSY only of that call fails as well (meaning that there's
> indeed someone using the particular device range we are trying to
> discard).
This missed -rc2, but I'll queue it up for -rc3.
--
Jens Axboe
