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| author | Mike Snitzer <snitzer@redhat.com> | 2010-12-17 08:34:20 +0100 |
|---|---|---|
| committer | Jens Axboe <jaxboe@fusionio.com> | 2010-12-17 08:36:01 +0100 |
| commit | 72d4cd9f38b5ed96b75df4c622be25e1c2648dd3 (patch) | |
| tree | a229645cbbc63aad3fa5b57ea9f092e618588890 /block/blk-settings.c | |
| parent | e692cb668fdd5a712c6ed2a2d6f2a36ee83997b4 (diff) | |
| download | lwn-72d4cd9f38b5ed96b75df4c622be25e1c2648dd3.tar.gz lwn-72d4cd9f38b5ed96b75df4c622be25e1c2648dd3.zip | |
block: max hardware sectors limit wrapper
Implement blk_limits_max_hw_sectors() and make
blk_queue_max_hw_sectors() a wrapper around it.
DM needs this to avoid setting queue_limits' max_hw_sectors and
max_sectors directly. dm_set_device_limits() now leverages
blk_limits_max_hw_sectors() logic to establish the appropriate
max_hw_sectors minimum (PAGE_SIZE). Fixes issue where DM was
incorrectly setting max_sectors rather than max_hw_sectors (which
caused dm_merge_bvec()'s max_hw_sectors check to be ineffective).
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@kernel.org
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Diffstat (limited to 'block/blk-settings.c')
| -rw-r--r-- | block/blk-settings.c | 26 |
1 files changed, 20 insertions, 6 deletions
diff --git a/block/blk-settings.c b/block/blk-settings.c index e55f5fc4ca22..36c8c1f2af18 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -229,8 +229,8 @@ void blk_queue_bounce_limit(struct request_queue *q, u64 dma_mask) EXPORT_SYMBOL(blk_queue_bounce_limit); /** - * blk_queue_max_hw_sectors - set max sectors for a request for this queue - * @q: the request queue for the device + * blk_limits_max_hw_sectors - set hard and soft limit of max sectors for request + * @limits: the queue limits * @max_hw_sectors: max hardware sectors in the usual 512b unit * * Description: @@ -244,7 +244,7 @@ EXPORT_SYMBOL(blk_queue_bounce_limit); * per-device basis in /sys/block/<device>/queue/max_sectors_kb. * The soft limit can not exceed max_hw_sectors. **/ -void blk_queue_max_hw_sectors(struct request_queue *q, unsigned int max_hw_sectors) +void blk_limits_max_hw_sectors(struct queue_limits *limits, unsigned int max_hw_sectors) { if ((max_hw_sectors << 9) < PAGE_CACHE_SIZE) { max_hw_sectors = 1 << (PAGE_CACHE_SHIFT - 9); @@ -252,9 +252,23 @@ void blk_queue_max_hw_sectors(struct request_queue *q, unsigned int max_hw_secto __func__, max_hw_sectors); } - q->limits.max_hw_sectors = max_hw_sectors; - q->limits.max_sectors = min_t(unsigned int, max_hw_sectors, - BLK_DEF_MAX_SECTORS); + limits->max_hw_sectors = max_hw_sectors; + limits->max_sectors = min_t(unsigned int, max_hw_sectors, + BLK_DEF_MAX_SECTORS); +} +EXPORT_SYMBOL(blk_limits_max_hw_sectors); + +/** + * blk_queue_max_hw_sectors - set max sectors for a request for this queue + * @q: the request queue for the device + * @max_hw_sectors: max hardware sectors in the usual 512b unit + * + * Description: + * See description for blk_limits_max_hw_sectors(). + **/ +void blk_queue_max_hw_sectors(struct request_queue *q, unsigned int max_hw_sectors) +{ + blk_limits_max_hw_sectors(&q->limits, max_hw_sectors); } EXPORT_SYMBOL(blk_queue_max_hw_sectors); |