Commit 4a4fc043 authored Aug 09, 2021 by Fengnan Chang Committed by Jaegeuk Kim Aug 17, 2021

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 <chao@kernel.org>
Signed-off-by: Fengnan Chang <changfengnan@vivo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

parent 1927ccdb

Documentation/filesystems/f2fs.rst

+5 −2

Original line number	Original line	Diff line number	Diff line
	@@ -865,8 +865,11 @@ Compression implementation
	directly in order to guarantee potential data updates later to the space.		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		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		possible, resulting in extending disk life time as well as relaxing IO
	congestion. Alternatively, we've added ioctl interface to reclaim compressed		congestion. Alternatively, we've added ioctl(F2FS_IOC_RELEASE_COMPRESS_BLOCKS)
	space and show it to user after putting the immutable bit.		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::		Compress metadata layout::

fs/f2fs/file.c

+8 −0

Original line number	Original line	Diff line number	Diff line
	@@ -753,6 +753,14 @@ int f2fs_truncate_blocks(struct inode *inode, u64 from, bool lock)
	return err;		return err;

	#ifdef CONFIG_F2FS_FS_COMPRESSION		#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) {		if (from != free_from) {
	err = f2fs_truncate_partial_cluster(inode, from, lock);		err = f2fs_truncate_partial_cluster(inode, from, lock);
	if (err)		if (err)