ext4: don't update s_rev_level if not required

Don't update the superblock s_rev_level during mount if it isn't
actually necessary, only if superblock features are being set by
the kernel.  This was originally added for ext3 since it always
set the INCOMPAT_RECOVER and HAS_JOURNAL features during mount,
but this is not needed since no journal mode was added to ext4.

That will allow Geert to mount his 20-year-old ext2 rev 0.0 m68k
filesystem, as a testament of the backward compatibility of ext4.

Fixes: 0390131ba8 ("ext4: Allow ext4 to run without a journal")
Signed-off-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Andreas Dilger 2019-02-14 17:52:18 -05:00 committed by Theodore Ts'o
parent a58ca99266
commit c9e716eb9b
3 changed files with 5 additions and 3 deletions

View File

@ -1665,6 +1665,8 @@ static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
#define EXT4_FEATURE_INCOMPAT_INLINE_DATA 0x8000 /* data in inode */
#define EXT4_FEATURE_INCOMPAT_ENCRYPT 0x10000
extern void ext4_update_dynamic_rev(struct super_block *sb);
#define EXT4_FEATURE_COMPAT_FUNCS(name, flagname) \
static inline bool ext4_has_feature_##name(struct super_block *sb) \
{ \
@ -1673,6 +1675,7 @@ static inline bool ext4_has_feature_##name(struct super_block *sb) \
} \
static inline void ext4_set_feature_##name(struct super_block *sb) \
{ \
ext4_update_dynamic_rev(sb); \
EXT4_SB(sb)->s_es->s_feature_compat |= \
cpu_to_le32(EXT4_FEATURE_COMPAT_##flagname); \
} \
@ -1690,6 +1693,7 @@ static inline bool ext4_has_feature_##name(struct super_block *sb) \
} \
static inline void ext4_set_feature_##name(struct super_block *sb) \
{ \
ext4_update_dynamic_rev(sb); \
EXT4_SB(sb)->s_es->s_feature_ro_compat |= \
cpu_to_le32(EXT4_FEATURE_RO_COMPAT_##flagname); \
} \
@ -1707,6 +1711,7 @@ static inline bool ext4_has_feature_##name(struct super_block *sb) \
} \
static inline void ext4_set_feature_##name(struct super_block *sb) \
{ \
ext4_update_dynamic_rev(sb); \
EXT4_SB(sb)->s_es->s_feature_incompat |= \
cpu_to_le32(EXT4_FEATURE_INCOMPAT_##flagname); \
} \
@ -2675,7 +2680,6 @@ do { \
#endif
extern void ext4_update_dynamic_rev(struct super_block *sb);
extern int ext4_update_compat_feature(handle_t *handle, struct super_block *sb,
__u32 compat);
extern int ext4_update_rocompat_feature(handle_t *handle,

View File

@ -5345,7 +5345,6 @@ static int ext4_do_update_inode(handle_t *handle,
err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh);
if (err)
goto out_brelse;
ext4_update_dynamic_rev(sb);
ext4_set_feature_large_file(sb);
ext4_handle_sync(handle);
err = ext4_handle_dirty_super(handle, sb);

View File

@ -2249,7 +2249,6 @@ static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
le16_add_cpu(&es->s_mnt_count, 1);
ext4_update_tstamp(es, s_mtime);
ext4_update_dynamic_rev(sb);
if (sbi->s_journal)
ext4_set_feature_journal_needs_recovery(sb);