ext4: make fsync to sync parent dir in no-journal for real this time (e12fb972) · Commits · 戴 / test

Previously commit added a support for for syncing parent directory of newly created inodes to make sure that the inode is not lost after a power failure in no-journal mode. However this does not work in majority of cases, namely: - if the directory has inline data - if the directory is already indexed - if the directory already has at least one block and: - the new entry fits into it - or we've successfully converted it to indexed So in those cases we might lose the inode entirely even after fsync in the no-journal mode. This also includes ext2 default mode obviously. I've noticed this while running xfstest generic/321 and even though the test should fail (we need to run fsck after a crash in no-journal mode) I could not find a newly created entries even when if it was fsynced before. Fix this by adjusting the ext4_add_entry() successful exit paths to set the inode EXT4_STATE_NEWENTRY so that fsync has the chance to fsync the parent directory as well. Signed-off-by:

Lukas Czerner <lczerner@redhat.com> Signed-off-by:

Theodore Ts'o <tytso@mit.edu> Reviewed-by:

Jan Kara <jack@suse.cz> Cc: Frank Mayhar <fmayhar@google.com> Cc: stable@vger.kernel.org

fs/ext4/namei.c

+11 −9

Original line number	Diff line number	Diff line
		@@ -1864,7 +1864,7 @@ static int ext4_add_entry(handle_t handle, struct dentry dentry,
		struct inode *inode)
		{
		struct inode *dir = dentry->d_parent->d_inode;
		struct buffer_head *bh;
		struct buffer_head *bh = NULL;
		struct ext4_dir_entry_2 *de;
		struct ext4_dir_entry_tail *t;
		struct super_block *sb;
		@@ -1888,14 +1888,14 @@ static int ext4_add_entry(handle_t handle, struct dentry dentry,
		return retval;
		if (retval == 1) {
		retval = 0;
		return retval;
		goto out;
		}
		}

		if (is_dx(dir)) {
		retval = ext4_dx_add_entry(handle, dentry, inode);
		if (!retval \|\| (retval != ERR_BAD_DX_DIR))
		return retval;
		goto out;
		ext4_clear_inode_flag(dir, EXT4_INODE_INDEX);
		dx_fallback++;
		ext4_mark_inode_dirty(handle, dir);
		@@ -1907,14 +1907,15 @@ static int ext4_add_entry(handle_t handle, struct dentry dentry,
		return PTR_ERR(bh);

		retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
		if (retval != -ENOSPC) {
		brelse(bh);
		return retval;
		}
		if (retval != -ENOSPC)
		goto out;

		if (blocks == 1 && !dx_fallback &&
		EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX))
		return make_indexed_dir(handle, dentry, inode, bh);
		EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX)) {
		retval = make_indexed_dir(handle, dentry, inode, bh);
		bh = NULL; /* make_indexed_dir releases bh */
		goto out;
		}
		brelse(bh);
		}
		bh = ext4_append(handle, dir, &block);
		@@ -1930,6 +1931,7 @@ static int ext4_add_entry(handle_t handle, struct dentry dentry,
		}

		retval = add_dirent_to_buf(handle, dentry, inode, de, bh);
		out:
		brelse(bh);
		if (retval == 0)
		ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY);

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