diff options
| author | Mike Snitzer <snitzer@redhat.com> | 2013-08-23 00:21:38 +0200 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2013-09-06 02:46:05 +0200 |
| commit | 169e2cc279c443085f7e423561eb1fe6158ade44 (patch) | |
| tree | 109acfea689865bb69e1c12a3ad36d34b8293429 /drivers/md/dm.h | |
| parent | math64: New separate div64_u64_rem helper (diff) | |
| download | linux-169e2cc279c443085f7e423561eb1fe6158ade44.tar.xz linux-169e2cc279c443085f7e423561eb1fe6158ade44.zip | |
dm: allow error target to replace bio-based and request-based targets
It may be useful to switch a request-based table to the "error" target.
Enhance the DM core to allow a hybrid target_type which is capable of
handling either bios (via .map) or requests (via .map_rq).
Add a request-based map function (.map_rq) to the "error" target_type;
making it DM's first hybrid target. Train dm_table_set_type() to prefer
the mapped device's established type (request-based or bio-based). If
the mapped device doesn't have an established type default to making the
table with the hybrid target(s) bio-based.
Tested 'dmsetup wipe_table' to work on both bio-based and request-based
devices.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Joe Jin <joe.jin@oracle.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Diffstat (limited to 'drivers/md/dm.h')
| -rw-r--r-- | drivers/md/dm.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/md/dm.h b/drivers/md/dm.h index 45b97da1bd06..8b4c075d9a2f 100644 --- a/drivers/md/dm.h +++ b/drivers/md/dm.h @@ -89,10 +89,21 @@ int dm_setup_md_queue(struct mapped_device *md); #define dm_target_is_valid(t) ((t)->table) /* + * To check whether the target type is bio-based or not (request-based). + */ +#define dm_target_bio_based(t) ((t)->type->map != NULL) + +/* * To check whether the target type is request-based or not (bio-based). */ #define dm_target_request_based(t) ((t)->type->map_rq != NULL) +/* + * To check whether the target type is a hybrid (capable of being + * either request-based or bio-based). + */ +#define dm_target_hybrid(t) (dm_target_bio_based(t) && dm_target_request_based(t)) + /*----------------------------------------------------------------- * A registry of target types. *---------------------------------------------------------------*/ |