From 4a4fc043f594d39edc976a3a3dce7c40ebb86f3f Mon Sep 17 00:00:00 2001 From: Fengnan Chang Date: Mon, 9 Aug 2021 10:21:04 +0800 Subject: f2fs: compress: allow write compress released file after truncate to zero For compressed file, after release compress blocks, don't allow write direct, but we should allow write direct after truncate to zero. Reviewed-by: Chao Yu Signed-off-by: Fengnan Chang Signed-off-by: Jaegeuk Kim --- Documentation/filesystems/f2fs.rst | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/f2fs.rst b/Documentation/filesystems/f2fs.rst index 8f251a662542..9b0517d90063 100644 --- a/Documentation/filesystems/f2fs.rst +++ b/Documentation/filesystems/f2fs.rst @@ -865,8 +865,11 @@ Compression implementation directly in order to guarantee potential data updates later to the space. Instead, the main goal is to reduce data writes to flash disk as much as possible, resulting in extending disk life time as well as relaxing IO - congestion. Alternatively, we've added ioctl interface to reclaim compressed - space and show it to user after putting the immutable bit. + congestion. Alternatively, we've added ioctl(F2FS_IOC_RELEASE_COMPRESS_BLOCKS) + interface to reclaim compressed space and show it to user after putting the + immutable bit. Immutable bit, after release, it doesn't allow writing/mmaping + on the file, until reserving compressed space via + ioctl(F2FS_IOC_RESERVE_COMPRESS_BLOCKS) or truncating filesize to zero. Compress metadata layout:: -- cgit