ich777/linux_media
1
0
Fork 0
mirror of https://github.com/tbsdtv/linux_media.git synced 2025-07-23 12:43:29 +02:00
Code Issues Packages Projects Releases Wiki Activity

block: allow 'chunk_sectors' to be non-power-of-2

Browse Source 
It is possible, albeit more unlikely, for a block device to have a non
power-of-2 for chunk_sectors (e.g. 10+2 RAID6 with 128K chunk_sectors,
which results in a full-stripe size of 1280K. This causes the RAID6's
io_opt to be advertised as 1280K, and a stacked device _could_ then be
made to use a blocksize, aka chunk_sectors, that matches non power-of-2
io_opt of underlying RAID6 -- resulting in stacked device's
chunk_sectors being a non power-of-2).

Update blk_queue_chunk_sectors() and blk_max_size_offset() to
accommodate drivers that need a non power-of-2 chunk_sectors.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Mike Snitzer
2020-09-21 22:32:49 -04:00
committed by Jens Axboe
parent 22ada802ed
commit 07d098e6bb
2 changed files with 13 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
include/linux/blkdev.h
View File

@@ -1063,11 +1063,17 @@ static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
static inline unsigned int blk_max_size_offset(struct request_queue *q,
sector_t offset)
{
if (!q->limits.chunk_sectors)
unsigned int chunk_sectors = q->limits.chunk_sectors;
if (!chunk_sectors)
return q->limits.max_sectors;
return min(q->limits.max_sectors, (unsigned int)(q->limits.chunk_sectors -
(offset & (q->limits.chunk_sectors - 1))));
if (likely(is_power_of_2(chunk_sectors)))
chunk_sectors -= offset & (chunk_sectors - 1);
else
chunk_sectors -= sector_div(offset, chunk_sectors);
return min(q->limits.max_sectors, chunk_sectors);
}
static inline unsigned int blk_rq_get_max_sectors(struct request *rq,