dm thin: add pool target flags to control discard

Add dm thin target arguments to control discard support.

ignore_discard: Disables discard support

no_discard_passdown: Don't pass discards down to the underlying data
device, but just remove the mapping within the thin provisioning target.

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>
This commit is contained in:
Joe Thornber
2012-03-28 18:41:29 +01:00
committed by Alasdair G Kergon
parent 104655fd4d
commit 67e2e2b281
2 changed files with 115 additions and 28 deletions

View File

@@ -223,7 +223,13 @@ i) Constructor
<low water mark (blocks)> [<number of feature args> [<arg>]*]
Optional feature arguments:
- 'skip_block_zeroing': skips the zeroing of newly-provisioned blocks.
skip_block_zeroing: Skip the zeroing of newly-provisioned blocks.
ignore_discard: Disable discard support.
no_discard_passdown: Don't pass discards down to the underlying
data device, but just remove the mapping.
Data block size must be between 64KB (128 sectors) and 1GB
(2097152 sectors) inclusive.