block: add a non-queueable flush flag

flush request isn't queueable in some drives. Add a flag to let driver
notify block layer about this. We can optimize flush performance with the
knowledge.

Stable: 2.6.39 only

Cc: stable@kernel.org
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
This commit is contained in:
shaohua.li@intel.com 2011-05-06 11:34:32 -06:00 committed by Jens Axboe
parent 490b94be02
commit f387693095
2 changed files with 13 additions and 0 deletions

View File

@ -790,6 +790,12 @@ void blk_queue_flush(struct request_queue *q, unsigned int flush)
}
EXPORT_SYMBOL_GPL(blk_queue_flush);
void blk_queue_flush_queueable(struct request_queue *q, bool queueable)
{
q->flush_not_queueable = !queueable;
}
EXPORT_SYMBOL_GPL(blk_queue_flush_queueable);
static int __init blk_settings_init(void)
{
blk_max_low_pfn = max_low_pfn - 1;

View File

@ -364,6 +364,7 @@ struct request_queue
* for flush operations
*/
unsigned int flush_flags;
unsigned int flush_not_queueable:1;
unsigned int flush_pending_idx:1;
unsigned int flush_running_idx:1;
unsigned long flush_pending_since;
@ -843,6 +844,7 @@ extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
extern void blk_queue_flush(struct request_queue *q, unsigned int flush);
extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
@ -1111,6 +1113,11 @@ static inline unsigned int block_size(struct block_device *bdev)
return bdev->bd_block_size;
}
static inline bool queue_flush_queueable(struct request_queue *q)
{
return !q->flush_not_queueable;
}
typedef struct {struct page *v;} Sector;
unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);