diff options
| author | Dolev Raviv <draviv@codeaurora.org> | 2015-07-01 12:52:25 +0300 |
|---|---|---|
| committer | David Keitel <dkeitel@codeaurora.org> | 2016-03-22 11:01:36 -0700 |
| commit | 59049166893ae5d883db1cd2706114a40391c0df (patch) | |
| tree | edff13a54113fc160df32018a33f437c87dad42e /include | |
| parent | 7472ef2e312ebc37de6a3194868773ed0f4dae8a (diff) | |
block: blk-flush: Add support for Barrier flag
A barrier request is used to control ordering of write requests without
clearing the device's cache. LLD support for barrier is optional. If LLD
doesn't support barrier, flush will be issued instead to insure logical
correctness.
To maintain this fallback flush s/w path and flags are appended.
This patch implements the necessary requests marking in order to support
the barrier feature in the block layer.
This patch implements two major changes required for the barrier support.
(1) A new flush execution-policy is added to support "ordered" requests
and a fallback , in case barrier is not supported by LLD.
(2) If there is a flush pending in the flush-queue, the received barrier
is ignored, in order not to miss a demand for an actual flush.
Change-Id: I6072d759e5c3bd983105852d81732e949da3d448
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/blk_types.h | 2 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 1 | ||||
| -rw-r--r-- | include/linux/fs.h | 7 |
3 files changed, 10 insertions, 0 deletions
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 6509574f9b95..d32400f5402b 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -161,6 +161,7 @@ enum rq_flag_bits { __REQ_INTEGRITY, /* I/O includes block integrity payload */ __REQ_FUA, /* forced unit access */ __REQ_FLUSH, /* request for cache flush */ + __REQ_POST_FLUSH_BARRIER,/* cache barrier after a data req */ __REQ_BARRIER, /* marks flush req as barrier */ /* bio only flags */ @@ -239,6 +240,7 @@ enum rq_flag_bits { #define REQ_ALLOCED (1ULL << __REQ_ALLOCED) #define REQ_COPY_USER (1ULL << __REQ_COPY_USER) #define REQ_FLUSH (1ULL << __REQ_FLUSH) +#define REQ_POST_FLUSH_BARRIER (1ULL << __REQ_POST_FLUSH_BARRIER) #define REQ_FLUSH_SEQ (1ULL << __REQ_FLUSH_SEQ) #define REQ_IO_STAT (1ULL << __REQ_IO_STAT) #define REQ_MIXED_MERGE (1ULL << __REQ_MIXED_MERGE) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index c70e3588a48c..0adfa9e76f64 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1118,6 +1118,7 @@ static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */ extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *); +extern int blkdev_issue_barrier(struct block_device *, gfp_t, sector_t *); extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector, sector_t nr_sects, gfp_t gfp_mask, unsigned long flags); extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, diff --git a/include/linux/fs.h b/include/linux/fs.h index 3aa514254161..605454ccaa0e 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -202,8 +202,15 @@ typedef void (dax_iodone_t)(struct buffer_head *bh_map, int uptodate); #define WRITE_SYNC (WRITE | REQ_SYNC | REQ_NOIDLE) #define WRITE_ODIRECT (WRITE | REQ_SYNC) #define WRITE_FLUSH (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH) +#define WRITE_FLUSH_BARRIER (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH | \ + REQ_BARRIER) #define WRITE_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FUA) #define WRITE_FLUSH_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH | REQ_FUA) +#define WRITE_POST_FLUSH_BARRIER (WRITE | REQ_SYNC | REQ_NOIDLE | \ + REQ_POST_FLUSH_BARRIER | REQ_BARRIER) +#define WRITE_ORDERED_FLUSH_BARRIER (WRITE | REQ_SYNC | REQ_NOIDLE | \ + REQ_FLUSH | REQ_POST_FLUSH_BARRIER | \ + REQ_BARRIER) /* * Attribute flags. These should be or-ed together to figure out what |