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authorMike Snitzer <snitzer@redhat.com>2020-09-22 05:32:49 +0300
committerJens Axboe <axboe@kernel.dk>2020-09-23 19:38:14 +0300
commit07d098e6bbad04030dab5b3e64149601fcb063ce (patch)
tree43d4d82eda0a5ea4e466a5ac0fd2125865e65b11 /block
parent22ada802ede89829dd010a317d9b812b7df7111a (diff)
downloadlinux-07d098e6bbad04030dab5b3e64149601fcb063ce.tar.xz
block: allow 'chunk_sectors' to be non-power-of-2
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>
Diffstat (limited to 'block')
-rw-r--r--block/blk-settings.c10
1 files changed, 4 insertions, 6 deletions
diff --git a/block/blk-settings.c b/block/blk-settings.c
index b2e1a929a6db..5ea3de48afba 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -172,15 +172,13 @@ EXPORT_SYMBOL(blk_queue_max_hw_sectors);
*
* Description:
* If a driver doesn't want IOs to cross a given chunk size, it can set
- * this limit and prevent merging across chunks. Note that the chunk size
- * must currently be a power-of-2 in sectors. Also note that the block
- * layer must accept a page worth of data at any offset. So if the
- * crossing of chunks is a hard limitation in the driver, it must still be
- * prepared to split single page bios.
+ * this limit and prevent merging across chunks. Note that the block layer
+ * must accept a page worth of data at any offset. So if the crossing of
+ * chunks is a hard limitation in the driver, it must still be prepared
+ * to split single page bios.
**/
void blk_queue_chunk_sectors(struct request_queue *q, unsigned int chunk_sectors)
{
- BUG_ON(!is_power_of_2(chunk_sectors));
q->limits.chunk_sectors = chunk_sectors;
}
EXPORT_SYMBOL(blk_queue_chunk_sectors);