diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-10-09 16:58:11 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-10-09 16:58:11 -0700 |
| commit | 0444555670350b419496686f4012b9cef808c105 (patch) | |
| tree | e9f20837bc0772829c6585ef21d70ee510a0e172 /Documentation | |
| parent | 175d58cfed70f132b8d4df39e19267ad6094bd16 (diff) | |
| parent | b0d3cc011e532d8c9db76cf717bcafa53c135595 (diff) | |
Merge tag 'dm-4.3-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull dm fixes from Mike Snitzer:
"Three stable fixes:
- DM core AB-BA deadlock fix in the device destruction path (vs
device creation's DM table swap).
- DM raid fix to properly round up the region_size to the next
power-of-2.
- DM cache fix for a NULL pointer seen while switching from the
"cleaner" cache policy.
Two fixes for regressions introduced during the 4.3 merge:
- request-based DM error propagation regressed due to incorrect
changes introduced when adding the bi_error field to bio.
- DM snapshot fix to only support snapshots that overflow if the
client (e.g. lvm2) is prepared to deal with the associated
snapshot status interface change"
* tag 'dm-4.3-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm snapshot: add new persistent store option to support overflow
dm cache: fix NULL pointer when switching from cleaner policy
dm: fix request-based dm error reporting
dm raid: fix round up of default region size
dm: fix AB-BA deadlock in __dm_destroy()
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/device-mapper/snapshot.txt | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/Documentation/device-mapper/snapshot.txt b/Documentation/device-mapper/snapshot.txt index 0d5bc46dc167..ad6949bff2e3 100644 --- a/Documentation/device-mapper/snapshot.txt +++ b/Documentation/device-mapper/snapshot.txt @@ -41,9 +41,13 @@ useless and be disabled, returning errors. So it is important to monitor the amount of free space and expand the <COW device> before it fills up. <persistent?> is P (Persistent) or N (Not persistent - will not survive -after reboot). -The difference is that for transient snapshots less metadata must be -saved on disk - they can be kept in memory by the kernel. +after reboot). O (Overflow) can be added as a persistent store option +to allow userspace to advertise its support for seeing "Overflow" in the +snapshot status. So supported store types are "P", "PO" and "N". + +The difference between persistent and transient is with transient +snapshots less metadata must be saved on disk - they can be kept in +memory by the kernel. * snapshot-merge <origin> <COW device> <persistent> <chunksize> |