zero-length bvec segments are allowed in general, but not handled by bio
and down the block layer so filtered out. This inconsistency may be
confusing and prevent from optimisations. As zero-length segments are
useless and places that were generating them are patched, declare them
not allowed.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
(cherry picked from commit 9b2e0016d04c6542ace0128eb82ecb3b10c97e43)
(cherry picked from commit 87afbd40acbb99860f846ad6f199e62e93be96c2)
(cherry picked from commit f0677085687d50b5ecd6e7a2e19e4aff23251cb6)
(cherry picked from commit affb154c088db678d4a541f8a4080fa5088cb10b)
(cherry picked from commit 9b383b80e8432af1d0421acf9287076db26996d7)
(cherry picked from commit f643066fcac50220888ecfe9b86c5d895d621648)
(cherry picked from commit d2f588cf9664d76f78287142f505e4f375503ae6)
Correct the comments since bfq_fifo_expire[0] is for async request,
while bfq_fifo_expire[1] is for sync request.
Also update docs, according the source code, the default
fifo_expire_async is 250ms, and fifo_expire_sync is 125ms.
Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
(cherry picked from commit 4168a8d27ed3a00f160e7f885c956f060d2a0741)
(cherry picked from commit a31ff2eb7d7cfa8331e513bb282f304117f18a77)
(cherry picked from commit a78637befaa4106f9858b3ad8e3273960d3de82b)
(cherry picked from commit bd8e7d3845c7a3b602aee361c7e3d0b5764ce060)
(cherry picked from commit a8543954accfadbb9a1cf1f64c6b3749ee3a629b)
(cherry picked from commit 960981f44b77dcd0d4e786aaef72d39057ccfc03)
(cherry picked from commit 50cfb4b6c1c2e4a3778f66510fee7a2e86e053f2)
[ Upstream commit a805a4fa4fa376bbc145762bb8b09caa2fa8af48 ]
Per ZBC and ZAC specifications, host-managed SMR hard-disks mandate that
all writes into sequential write required zones be aligned to the device
physical block size. However, NVMe ZNS does not have this constraint and
allows write operations into sequential zones to be aligned to the
device logical block size. This inconsistency does not help with
software portability across device types.
To solve this, introduce the zone_write_granularity queue limit to
indicate the alignment constraint, in bytes, of write operations into
zones of a zoned block device. This new limit is exported as a
read-only sysfs queue attribute and the helper
blk_queue_zone_write_granularity() introduced for drivers to set this
limit.
The function blk_queue_set_zoned() is modified to set this new limit to
the device logical block size by default. NVMe ZNS devices as well as
zoned nullb devices use this default value as is. The scsi disk driver
is modified to execute the blk_queue_zone_write_granularity() helper to
set the zone write granularity of host-managed SMR disks to the disk
physical block size.
The accessor functions queue_zone_write_granularity() and
bdev_zone_write_granularity() are also introduced.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@edc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: c8f6f88d2592 ("block: Clear zone limits for a non-zoned stacked queue")
Signed-off-by: Sasha Levin <sashal@kernel.org>
