These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / Documentation / device-mapper / cache.txt

diff --git a/kernel/Documentation/device-mapper/cache.txt b/kernel/Documentation/device-mapper/cache.txt
index 68c0f51..785eab8 100644 (file)
--- a/kernel/Documentation/device-mapper/cache.txt
+++ b/kernel/Documentation/device-mapper/cache.txt
@@ -221,6 +221,7 @@ Status
 <#read hits> <#read misses> <#write hits> <#write misses>
 <#demotions> <#promotions> <#dirty> <#features> <features>*
 <#core args> <core args>* <policy name> <#policy args> <policy args>*
+<cache metadata mode>
 
 metadata block size     : Fixed block size for each metadata block in
                             sectors
@@ -251,8 +252,18 @@ core args           : Key/value pairs for tuning the core
                             e.g. migration_threshold
 policy name             : Name of the policy
 #policy args            : Number of policy arguments to follow (must be even)
-policy args             : Key/value pairs
-                            e.g. sequential_threshold
+policy args             : Key/value pairs e.g. sequential_threshold
+cache metadata mode      : ro if read-only, rw if read-write
+       In serious cases where even a read-only mode is deemed unsafe
+       no further I/O will be permitted and the status will just
+       contain the string 'Fail'.  The userspace recovery tools
+       should then be used.
+needs_check             : 'needs_check' if set, '-' if not set
+       A metadata operation has failed, resulting in the needs_check
+       flag being set in the metadata's superblock.  The metadata
+       device must be deactivated and checked/repaired before the
+       cache can be made fully operational again.  '-' indicates
+       needs_check is not set.
 
 Messages
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