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Diffstat (limited to 'Documentation/md.txt')
| -rw-r--r-- | Documentation/md.txt | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/Documentation/md.txt b/Documentation/md.txt index 18fad6876228..21d26fb5d02b 100644 --- a/Documentation/md.txt +++ b/Documentation/md.txt @@ -322,6 +322,22 @@ All md devices contain: 'backlog' sets a limit on the number of concurrent background writes. If there are more than this, new writes will by synchronous. + bitmap/metadata + This can be either 'internal' or 'external'. + 'internal' is the default and means the metadata for the bitmap + is stored in the first 256 bytes of the allocated space and is + managed by the md module. + 'external' means that bitmap metadata is managed externally to + the kernel (i.e. by some userspace program) + bitmap/can_clear + This is either 'true' or 'false'. If 'true', then bits in the + bitmap will be cleared when the corresponding blocks are thought + to be in-sync. If 'false', bits will never be cleared. + This is automatically set to 'false' if a write happens on a + degraded array, or if the array becomes degraded during a write. + When metadata is managed externally, it should be set to true + once the array becomes non-degraded, and this fact has been + recorded in the metadata. |