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Diffstat (limited to 'Documentation/filesystems/porting')
-rw-r--r-- | Documentation/filesystems/porting | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting index 7fcac6393cd..dfbcd1b00b0 100644 --- a/Documentation/filesystems/porting +++ b/Documentation/filesystems/porting @@ -385,3 +385,12 @@ Documentation/filesystems/vfs.txt for more details. on many or all directory inodes on the way down a path walk (to check for exec permission). These must now be rcu-walk aware (flags & IPERM_FLAG_RCU). See Documentation/filesystems/vfs.txt for more details. + +-- +[mandatory] + In ->fallocate() you must check the mode option passed in. If your +filesystem does not support hole punching (deallocating space in the middle of a +file) you must return -EOPNOTSUPP if FALLOC_FL_PUNCH_HOLE is set in mode. +Currently you can only have FALLOC_FL_PUNCH_HOLE with FALLOC_FL_KEEP_SIZE set, +so the i_size should not change when hole punching, even when puching the end of +a file off. |