From: Fengnan Chang Date: Mon, 9 Aug 2021 02:21:04 +0000 (+0800) Subject: f2fs: compress: allow write compress released file after truncate to zero X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=4a4fc043f594d39edc976a3a3dce7c40ebb86f3f;p=linux.git 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 --- diff --git a/Documentation/filesystems/f2fs.rst b/Documentation/filesystems/f2fs.rst index 8f251a6625424..9b0517d900637 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:: diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 7d8ee60f6c1f9..d4fc5e0d2ffe1 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -753,6 +753,14 @@ int f2fs_truncate_blocks(struct inode *inode, u64 from, bool lock) return err; #ifdef CONFIG_F2FS_FS_COMPRESSION + /* + * For compressed file, after release compress blocks, don't allow write + * direct, but we should allow write direct after truncate to zero. + */ + if (f2fs_compressed_file(inode) && !free_from + && is_inode_flag_set(inode, FI_COMPRESS_RELEASED)) + clear_inode_flag(inode, FI_COMPRESS_RELEASED); + if (from != free_from) { err = f2fs_truncate_partial_cluster(inode, from, lock); if (err)