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From:   Jeff Layton <jlayton@kernel.org>
To:     tytso@mit.edu, adilger.kernel@dilger.ca
Cc:     linux-ext4@vger.kernel.org, Dave Chinner <david@fromorbit.com>,
        Lukas Czerner <lczerner@redhat.com>,
        Benjamin Coddington <bcodding@redhat.com>,
        Christoph Hellwig <hch@infradead.org>
Subject: [PATCH] ext4: unconditionally enable the i_version counter
Date:   Mon, 25 Jul 2022 15:29:46 -0400
Message-Id: <20220725192946.330619-1-jlayton@kernel.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

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.

Have ext4 ignore the SB_I_VERSION flag, and just enable it
unconditionally.

Cc: Dave Chinner <david@fromorbit.com>
Cc: Lukas Czerner <lczerner@redhat.com>
Cc: Benjamin Coddington <bcodding@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 fs/ext4/inode.c | 5 ++---
 fs/ext4/super.c | 8 ++++----
 2 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 84c0eb55071d..c785c0b72116 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5411,7 +5411,7 @@ int ext4_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
 			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) {
@@ -5717,8 +5717,7 @@ int ext4_mark_iloc_dirty(handle_t *handle,
 	}
 	ext4_fc_track_inode(handle, inode);
 
-	if (IS_I_VERSION(inode))
-		inode_inc_iversion(inode);
+	inode_inc_iversion(inode);
 
 	/* the do_update_inode consumes one bh->b_count */
 	get_bh(iloc->bh);
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 845f2f8aee5f..30645d4343b6 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2142,8 +2142,7 @@ static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
 		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);
+		ext4_msg(NULL, KERN_WARNING, "i_version counter is always enabled.\n");
 		return 0;
 	case Opt_inlinecrypt:
 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
@@ -2970,8 +2969,6 @@ static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
 		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 &
@@ -4630,6 +4627,9 @@ static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
 	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) ||
-- 
2.37.1