block: Add a wrapper for setting minimum request size without a queue

Introduce blk_limits_io_min() and make blk_queue_io_min() call it.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
Martin K. Petersen 2009-07-31 11:49:11 -04:00 committed by Jens Axboe
parent fef246672b
commit 7c958e3264
2 changed files with 25 additions and 7 deletions

View File

@ -383,6 +383,29 @@ void blk_queue_alignment_offset(struct request_queue *q, unsigned int offset)
}
EXPORT_SYMBOL(blk_queue_alignment_offset);
/**
* blk_limits_io_min - set minimum request size for a device
* @limits: the queue limits
* @min: smallest I/O size in bytes
*
* Description:
* Some devices have an internal block size bigger than the reported
* hardware sector size. This function can be used to signal the
* smallest I/O the device can perform without incurring a performance
* penalty.
*/
void blk_limits_io_min(struct queue_limits *limits, unsigned int min)
{
limits->io_min = min;
if (limits->io_min < limits->logical_block_size)
limits->io_min = limits->logical_block_size;
if (limits->io_min < limits->physical_block_size)
limits->io_min = limits->physical_block_size;
}
EXPORT_SYMBOL(blk_limits_io_min);
/**
* blk_queue_io_min - set minimum request size for the queue
* @q: the request queue for the device
@ -396,13 +419,7 @@ EXPORT_SYMBOL(blk_queue_alignment_offset);
*/
void blk_queue_io_min(struct request_queue *q, unsigned int min)
{
q->limits.io_min = min;
if (q->limits.io_min < q->limits.logical_block_size)
q->limits.io_min = q->limits.logical_block_size;
if (q->limits.io_min < q->limits.physical_block_size)
q->limits.io_min = q->limits.physical_block_size;
blk_limits_io_min(&q->limits, min);
}
EXPORT_SYMBOL(blk_queue_io_min);

View File

@ -913,6 +913,7 @@ extern void blk_queue_logical_block_size(struct request_queue *, unsigned short)
extern void blk_queue_physical_block_size(struct request_queue *, unsigned short);
extern void blk_queue_alignment_offset(struct request_queue *q,
unsigned int alignment);
extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
extern void blk_set_default_limits(struct queue_limits *lim);