From: Yu Kuai <[email protected]> In order to make code related to sync_thread cleaner in following patches, also add detail comment about each sync action.
Signed-off-by: Yu Kuai <[email protected]> --- drivers/md/md.h | 57 ++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 56 insertions(+), 1 deletion(-) diff --git a/drivers/md/md.h b/drivers/md/md.h index 2a1cb7b889e5..2edad966f90a 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -34,6 +34,61 @@ */ #define MD_FAILFAST (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT) +/* Status of sync thread. */ +enum sync_action { + /* + * Represent by MD_RECOVERY_SYNC, start when: + * 1) after assemble, sync data from first rdev to other copies, this + * must be done first before other sync actions and will only execute + * once; + * 2) resize the array(notice that this is not reshape), sync data for + * the new range; + */ + ACTION_RESYNC, + /* + * Represent by MD_RECOVERY_RECOVER, start when: + * 1) for new replacement, sync data based on the replace rdev or + * available copies from other rdev; + * 2) for new member disk while the array is degraded, sync data from + * other rdev; + * 3) reassemble after power failure or re-add a hot removed rdev, sync + * data from first rdev to other copies based on bitmap; + */ + ACTION_RECOVER, + /* + * Represent by MD_RECOVERY_SYNC | MD_RECOVERY_REQUESTED | + * MD_RECOVERY_CHECK, start when user echo "check" to sysfs api + * sync_action, used to check if data copies from differenct rdev are + * the same. The number of mismatch sectors will be exported to user + * by sysfs api mismatch_cnt; + */ + ACTION_CHECK, + /* + * Represent by MD_RECOVERY_SYNC | MD_RECOVERY_REQUESTED, start when + * user echo "repair" to sysfs api sync_action, usually paired with + * ACTION_CHECK, used to force syncing data once user found that there + * are inconsistent data, + */ + ACTION_REPAIR, + /* + * Represent by MD_RECOVERY_RESHAPE, start when new member disk is added + * to the conf, notice that this is different from spares or + * replacement; + */ + ACTION_RESHAPE, + /* + * Represent by MD_RECOVERY_FROZEN, can be set by sysfs api sync_action + * or internal usage like setting the array read-only, will forbid above + * actions. + */ + ACTION_FROZEN, + /* + * All above actions don't match. + */ + ACTION_IDLE, + NR_SYNC_ACTIONS, +}; + /* * The struct embedded in rdev is used to serialize IO. */ @@ -571,7 +626,7 @@ enum recovery_flags { /* interrupted because io-error */ MD_RECOVERY_ERROR, - /* flags determines sync action */ + /* flags determines sync action, see details in enum sync_action */ /* if just this flag is set, action is resync. */ MD_RECOVERY_SYNC, -- 2.39.2
