[PATCH 5.19 128/717] ext4: unconditionally enable the i_version counter

Greg Kroah-Hartman
2022-10-22T07:42:56Z

From: Jeff Layton <jlayton@kernel.org>

commit 1ff20307393e17dc57fde62226df625a3a3c36e9 upstream.

The original i_version implementation was pretty expensive, requiring a
log flush on every change. Because of this, it was gated behind a mount
option (implemented via the MS_I_VERSION mountoption flag).

Commit ae5e165d855d (fs: new API for handling inode->i_version) made the
i_version flag much less expensive, so there is no longer a performance
penalty from enabling it. xfs and btrfs already enable it
unconditionally when the on-disk format can support it.

Have ext4 ignore the SB_I_VERSION flag, and just enable it
unconditionally. While we're in here, mark the i_version mount
option Opt_removed.

[ Removed leftover bits of i_version from ext4_apply_options() since it
now can't ever be set in ctx->mask_s_flags -- lczerner ]

Cc: stable@kernel.org
Cc: Dave Chinner <david@fromorbit.com>
Cc: Benjamin Coddington <bcodding@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220824160349.39664-3-lczerner@redhat.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/ext4/inode.c | 5 ++---
fs/ext4/super.c | 22 +++++-----------------
2 files changed, 7 insertions(+), 20 deletions(-)

--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5425,7 +5425,7 @@ int ext4_setattr(struct user_namespace *
return -EINVAL;
}

- if (IS_I_VERSION(inode) && attr->ia_size != inode->i_size)
+ if (attr->ia_size != inode->i_size)
inode_inc_iversion(inode);

if (shrink) {
@@ -5735,8 +5735,7 @@ int ext4_mark_iloc_dirty(handle_t *handl
* ea_inodes are using i_version for storing reference count, don't
* mess with it
*/
- if (IS_I_VERSION(inode) &&
- !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL))
+ if (!(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL))
inode_inc_iversion(inode);

/* the do_update_inode consumes one bh->b_count */
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1585,7 +1585,7 @@ enum {
Opt_inlinecrypt,
Opt_usrjquota, Opt_grpjquota, Opt_quota,
Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
- Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
+ Opt_usrquota, Opt_grpquota, Opt_prjquota,
Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
Opt_nowarn_on_error, Opt_mblk_io_submit, Opt_debug_want_extra_isize,
@@ -1694,7 +1694,7 @@ static const struct fs_parameter_spec ex
fsparam_flag ("barrier", Opt_barrier),
fsparam_u32 ("barrier", Opt_barrier),
fsparam_flag ("nobarrier", Opt_nobarrier),
- fsparam_flag ("i_version", Opt_i_version),
+ fsparam_flag ("i_version", Opt_removed),
fsparam_flag ("dax", Opt_dax),
fsparam_enum ("dax", Opt_dax_type, ext4_param_dax),
fsparam_u32 ("stripe", Opt_stripe),
@@ -2140,11 +2140,6 @@ static int ext4_parse_param(struct fs_co
case Opt_abort:
ctx_set_mount_flag(ctx, EXT4_MF_FS_ABORTED);
return 0;
- case Opt_i_version:
- ext4_msg(NULL, KERN_WARNING, deprecated_msg, param->key, "5.20");
- ext4_msg(NULL, KERN_WARNING, "Use iversion instead\n");
- ctx_set_flags(ctx, SB_I_VERSION);
- return 0;
case Opt_inlinecrypt:
#ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
ctx_set_flags(ctx, SB_INLINECRYPT);
@@ -2814,14 +2809,6 @@ static void ext4_apply_options(struct fs
sb->s_flags &= ~ctx->mask_s_flags;
sb->s_flags |= ctx->vals_s_flags;

- /*
- * i_version differs from common mount option iversion so we have
- * to let vfs know that it was set, otherwise it would get cleared
- * on remount
- */
- if (ctx->mask_s_flags & SB_I_VERSION)
- fc->sb_flags |= SB_I_VERSION;
-
#define APPLY(X) ({ if (ctx->spec & EXT4_SPEC_##X) sbi->X = ctx->X; })
APPLY(s_commit_interval);
APPLY(s_stripe);
@@ -2970,8 +2957,6 @@ static int _ext4_show_options(struct seq
SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
- if (sb->s_flags & SB_I_VERSION)
- SEQ_OPTS_PUTS("i_version");
if (nodefs || sbi->s_stripe)
SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
if (nodefs || EXT4_MOUNT_DATA_FLAGS &
@@ -4631,6 +4616,9 @@ static int __ext4_fill_super(struct fs_c
sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);

+ /* i_version is always enabled now */
+ sb->s_flags |= SB_I_VERSION;
+
if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
(ext4_has_compat_features(sb) ||
ext4_has_ro_compat_features(sb) ||