dm thin: add read only and fail io modes
authorJoe Thornber <ejt@redhat.com>
Fri, 27 Jul 2012 14:08:16 +0000 (15:08 +0100)
committerAlasdair G Kergon <agk@redhat.com>
Fri, 27 Jul 2012 14:08:16 +0000 (15:08 +0100)
commite49e582965b3694f07a106adc83ddb44aa4f0890
treefcc6ff02fd4bd9afa59b5fd3bdbb9991f1271d8a
parentda105ed5fd7edcc5e0df7dbacef4dadda74e7ebe
dm thin: add read only and fail io modes

Add read-only and fail-io modes to thin provisioning.

If a transaction commit fails the pool's metadata device will transition
to "read-only" mode.  If a commit fails once already in read-only mode
the transition to "fail-io" mode occurs.

Once in fail-io mode the pool and all associated thin devices will
report a status of "Fail".

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Documentation/device-mapper/thin-provisioning.txt
drivers/md/dm-thin.c