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| author | Jonathan Brassow <jbrassow@redhat.com> | 2012-10-11 13:40:24 +1100 |
|---|---|---|
| committer | NeilBrown <neilb@suse.de> | 2012-10-11 13:40:24 +1100 |
| commit | 4ec1e369af83f7ecdfbd48a905e44fc9910115ba (patch) | |
| tree | 5e7287f870140e041190604ede472ae4d7fa2baf | |
| parent | eb6491236f283eb6ebc5421fcdb14b86701a7e36 (diff) | |
| download | linux-4ec1e369af83f7ecdfbd48a905e44fc9910115ba.tar.gz linux-4ec1e369af83f7ecdfbd48a905e44fc9910115ba.tar.bz2 linux-4ec1e369af83f7ecdfbd48a905e44fc9910115ba.zip | |
DM RAID: Add rebuild capability for RAID10
DM RAID: Add code to validate replacement slots for RAID10 arrays
RAID10 can handle 'copies - 1' failures for each mirror group. This code
ensures the user has provided a valid array - one whose devices specified for
rebuild do not exceed the amount of redundancy available.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
| -rw-r--r-- | Documentation/device-mapper/dm-raid.txt | 9 | ||||
| -rw-r--r-- | drivers/md/dm-raid.c | 34 |
2 files changed, 42 insertions, 1 deletions
diff --git a/Documentation/device-mapper/dm-raid.txt b/Documentation/device-mapper/dm-raid.txt index 1c1844957166..728c38c242d6 100644 --- a/Documentation/device-mapper/dm-raid.txt +++ b/Documentation/device-mapper/dm-raid.txt @@ -132,3 +132,12 @@ Here we can see the RAID type is raid4, there are 5 devices - all of which are 'A'live, and the array is 2/490221568 complete with recovery. Faulty or missing devices are marked 'D'. Devices that are out-of-sync are marked 'a'. + + +Version History +--------------- +1.0.0 Initial version. Support for RAID 4/5/6 +1.1.0 Added support for RAID 1 +1.2.0 Handle creation of arrays that contain failed devices. +1.3.0 Added support for RAID 10 +1.3.1 Allow device replacement/rebuild for RAID 10 diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c index 10635e965fec..4e79ebaab3c1 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -349,6 +349,7 @@ static int validate_region_size(struct raid_set *rs, unsigned long region_size) static int validate_rebuild_devices(struct raid_set *rs) { unsigned i, rebuild_cnt = 0; + unsigned rebuilds_per_group, copies, d; if (!(rs->print_flags & DMPF_REBUILD)) return 0; @@ -369,6 +370,37 @@ static int validate_rebuild_devices(struct raid_set *rs) goto too_many; break; case 10: + copies = raid10_md_layout_to_copies(rs->md.layout); + if (rebuild_cnt < copies) + break; + + /* + * It is possible to have a higher rebuild count for RAID10, + * as long as the failed devices occur in different mirror + * groups (i.e. different stripes). + * + * Right now, we only allow for "near" copies. When other + * formats are added, we will have to check those too. + * + * When checking "near" format, make sure no adjacent devices + * have failed beyond what can be handled. In addition to the + * simple case where the number of devices is a multiple of the + * number of copies, we must also handle cases where the number + * of devices is not a multiple of the number of copies. + * E.g. dev1 dev2 dev3 dev4 dev5 + * A A B B C + * C D D E E + */ + rebuilds_per_group = 0; + for (i = 0; i < rs->md.raid_disks * copies; i++) { + d = i % rs->md.raid_disks; + if (!test_bit(In_sync, &rs->dev[d].rdev.flags) && + (++rebuilds_per_group >= copies)) + goto too_many; + if (!((i + 1) % copies)) + rebuilds_per_group = 0; + } + break; default: DMERR("The rebuild parameter is not supported for %s", rs->raid_type->name); @@ -1385,7 +1417,7 @@ static void raid_resume(struct dm_target *ti) static struct target_type raid_target = { .name = "raid", - .version = {1, 3, 0}, + .version = {1, 3, 1}, .module = THIS_MODULE, .ctr = raid_ctr, .dtr = raid_dtr, |