Commit d3ba7afc authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'ext4_for_linus_bugfixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 

Pull ext4 fixes from Ted Ts'o:
 "Two ext4 bug fixes, one being a revert of a commit sent during the
  merge window"

* tag 'ext4_for_linus_bugfixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  Revert "ext4: fix superblock checksum calculation race"
  ext4: handle dax mount option collision
parents 585e5b17 d196e229

fs/ext4/ext4.h

+3 −3
Original line number Diff line number Diff line
@@ -1231,13 +1231,13 @@ struct ext4_inode_info { 
						      blocks */

#define EXT4_MOUNT2_HURD_COMPAT		0x00000004 /* Support HURD-castrated

						      file systems */

#define EXT4_MOUNT2_DAX_NEVER		0x00000008 /* Do not allow Direct Access */

#define EXT4_MOUNT2_DAX_INODE		0x00000010 /* For printing options only */



#define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly

						specified journal checksum */



#define EXT4_MOUNT2_JOURNAL_FAST_COMMIT	0x00000010 /* Journal fast commit */

#define EXT4_MOUNT2_DAX_NEVER		0x00000020 /* Do not allow Direct Access */

#define EXT4_MOUNT2_DAX_INODE		0x00000040 /* For printing options only */





#define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \

						~EXT4_MOUNT_##opt

fs/ext4/super.c

+0 −11
Original line number Diff line number Diff line
@@ -289,18 +289,7 @@ void ext4_superblock_csum_set(struct super_block *sb) 
	if (!ext4_has_metadata_csum(sb))

		return;



	/*

	 * Locking the superblock prevents the scenario

	 * where:

	 *  1) a first thread pauses during checksum calculation.

	 *  2) a second thread updates the superblock, recalculates

	 *     the checksum, and updates s_checksum

	 *  3) the first thread resumes and finishes its checksum calculation

	 *     and updates s_checksum with a potentially stale or torn value.

	 */

	lock_buffer(EXT4_SB(sb)->s_sbh);

	es->s_checksum = ext4_superblock_csum(sb, es);

	unlock_buffer(EXT4_SB(sb)->s_sbh);

}



ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,