On 3/17/23 15:39, Damien Le Moal wrote:
On 3/18/23 04:50, Bart Van Assche wrote:
Make it easier for filesystems to submit zone append bios that exceed
the block device limits by adding support for REQ_OP_ZONE_APPEND in
bio_split(). See also commit 0512a75b98f8 ("block: Introduce
REQ_OP_ZONE_APPEND").
This patch is a bug fix for commit d5e4377d5051 because that commit
introduces a call to bio_split() for zone append bios without adding
support for splitting REQ_OP_ZONE_APPEND bios in bio_split().
Untested.
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Keith Busch <kbusch@xxxxxxxxxx>
Cc: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>
Cc: Josef Bacik <josef@xxxxxxxxxxxxxx>
Cc: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Fixes: d5e4377d5051 ("btrfs: split zone append bios in btrfs_submit_bio")
Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
Nack. This will break zonefs.
zonefs uses zone append commands for sync writes. If zonefs does not have
guarantees that a single write is processed with a single command, the user data
can get corrupted because of the possible reordering of zone append commands.
Hi Damien,
It is not clear to me how this would break zonefs? Is my understanding
correct that the size of bios built by zonefs is such that bio_split()
won't split these?
Thanks,
Bart.
