diff options
| author | Joe Thornber <ejt@redhat.com> | 2014-09-17 10:17:39 +0100 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2014-11-10 15:25:30 -0500 |
| commit | 5f274d886598c9fd26d2499bf3f68306f170e9db (patch) | |
| tree | af0ded19382c65e832ea51e2b01efb40581c81dd /drivers/md/dm-bio-prison.h | |
| parent | f1afb36a6102b52949c2c6d8eb250eddcce3fc5f (diff) | |
dm bio prison: introduce support for locking ranges of blocks
Ranges will be placed in the same cell if they overlap.
Range locking is a prerequisite for more efficient multi-block discard
support in both the cache and thin-provisioning targets.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md/dm-bio-prison.h')
| -rw-r--r-- | drivers/md/dm-bio-prison.h | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/drivers/md/dm-bio-prison.h b/drivers/md/dm-bio-prison.h index b03988667740..74cf01144b1f 100644 --- a/drivers/md/dm-bio-prison.h +++ b/drivers/md/dm-bio-prison.h @@ -23,11 +23,14 @@ */ struct dm_bio_prison; -/* FIXME: this needs to be more abstract */ +/* + * Keys define a range of blocks within either a virtual or physical + * device. + */ struct dm_cell_key { int virtual; dm_thin_id dev; - dm_block_t block; + dm_block_t block_begin, block_end; }; /* @@ -59,7 +62,7 @@ void dm_bio_prison_free_cell(struct dm_bio_prison *prison, struct dm_bio_prison_cell *cell); /* - * Creates, or retrieves a cell for the given key. + * Creates, or retrieves a cell that overlaps the given key. * * Returns 1 if pre-existing cell returned, zero if new cell created using * @cell_prealloc. @@ -70,7 +73,8 @@ int dm_get_cell(struct dm_bio_prison *prison, struct dm_bio_prison_cell **cell_result); /* - * An atomic op that combines retrieving a cell, and adding a bio to it. + * An atomic op that combines retrieving or creating a cell, and adding a + * bio to it. * * Returns 1 if the cell was already held, 0 if @inmate is the new holder. */ |