ext4: return early for non-eligible fast_commit track events

Currently ext4_fc_track_template() checks, whether the trace event
path belongs to replay or does sb has ineligible set, if yes it simply
returns. This patch pulls those checks before calling
ext4_fc_track_template() in the callers of ext4_fc_track_template().

[ Add checks to ext4_rename() which calls the __ext4_fc_track_*()
  functions directly. -- TYT ]
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/3cd025d9c490218a92e6d8fb30b6123e693373e3.1647057583.git.riteshh@linux.ibm.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

fs/ext4/fast_commit.c

@@ -379,13 +379,6 @@ static int ext4_fc_track_template(
 	tid_t tid = 0;
 	int ret;
 
-	if (!test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT) ||
-	    (sbi->s_mount_state & EXT4_FC_REPLAY))
-		return -EOPNOTSUPP;
-
-	if (ext4_test_mount_flag(inode->i_sb, EXT4_MF_FC_INELIGIBLE))
-		return -EINVAL;
-
 	tid = handle->h_transaction->t_tid;
 	mutex_lock(&ei->i_fc_lock);
 	if (tid == ei->i_sync_tid) {
@@ -499,7 +492,17 @@ void __ext4_fc_track_unlink(handle_t *handle,
 
 void ext4_fc_track_unlink(handle_t *handle, struct dentry *dentry)
 {
-	__ext4_fc_track_unlink(handle, d_inode(dentry), dentry);
+	struct inode *inode = d_inode(dentry);
+	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+
+	if (!test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT) ||
+	    (sbi->s_mount_state & EXT4_FC_REPLAY))
+		return;
+
+	if (ext4_test_mount_flag(inode->i_sb, EXT4_MF_FC_INELIGIBLE))
+		return;
+
+	__ext4_fc_track_unlink(handle, inode, dentry);
 }
 
 void __ext4_fc_track_link(handle_t *handle,
@@ -518,7 +521,17 @@ void __ext4_fc_track_link(handle_t *handle,
 
 void ext4_fc_track_link(handle_t *handle, struct dentry *dentry)
 {
-	__ext4_fc_track_link(handle, d_inode(dentry), dentry);
+	struct inode *inode = d_inode(dentry);
+	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+
+	if (!test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT) ||
+	    (sbi->s_mount_state & EXT4_FC_REPLAY))
+		return;
+
+	if (ext4_test_mount_flag(inode->i_sb, EXT4_MF_FC_INELIGIBLE))
+		return;
+
+	__ext4_fc_track_link(handle, inode, dentry);
 }
 
 void __ext4_fc_track_create(handle_t *handle, struct inode *inode,
@@ -537,7 +550,17 @@ void __ext4_fc_track_create(handle_t *handle, struct inode *inode,
 
 void ext4_fc_track_create(handle_t *handle, struct dentry *dentry)
 {
-	__ext4_fc_track_create(handle, d_inode(dentry), dentry);
+	struct inode *inode = d_inode(dentry);
+	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+
+	if (!test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT) ||
+	    (sbi->s_mount_state & EXT4_FC_REPLAY))
+		return;
+
+	if (ext4_test_mount_flag(inode->i_sb, EXT4_MF_FC_INELIGIBLE))
+		return;
+
+	__ext4_fc_track_create(handle, inode, dentry);
 }
 
 /* __track_fn for inode tracking */
@@ -553,6 +576,7 @@ static int __track_inode(struct inode *inode, void *arg, bool update)
 
 void ext4_fc_track_inode(handle_t *handle, struct inode *inode)
 {
+	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
 	int ret;
 
 	if (S_ISDIR(inode->i_mode))
@@ -564,6 +588,13 @@ void ext4_fc_track_inode(handle_t *handle, struct inode *inode)
 		return;
 	}
 
+	if (!test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT) ||
+	    (sbi->s_mount_state & EXT4_FC_REPLAY))
+		return;
+
+	if (ext4_test_mount_flag(inode->i_sb, EXT4_MF_FC_INELIGIBLE))
+		return;
+
 	ret = ext4_fc_track_template(handle, inode, __track_inode, NULL, 1);
 	trace_ext4_fc_track_inode(inode, ret);
 }
@@ -603,12 +634,20 @@ static int __track_range(struct inode *inode, void *arg, bool update)
 void ext4_fc_track_range(handle_t *handle, struct inode *inode, ext4_lblk_t start,
 			 ext4_lblk_t end)
 {
+	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
 	struct __track_range_args args;
 	int ret;
 
 	if (S_ISDIR(inode->i_mode))
 		return;
 
+	if (!test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT) ||
+	    (sbi->s_mount_state & EXT4_FC_REPLAY))
+		return;
+
+	if (ext4_test_mount_flag(inode->i_sb, EXT4_MF_FC_INELIGIBLE))
+		return;
+
 	args.start = start;
 	args.end = end;
 

fs/ext4/namei.c

@@ -3891,12 +3891,19 @@ static int ext4_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
 		ext4_fc_mark_ineligible(old.inode->i_sb,
 			EXT4_FC_REASON_RENAME_DIR, handle);
 	} else {
+		struct super_block *sb = old.inode->i_sb;
+
 		if (new.inode)
 			ext4_fc_track_unlink(handle, new.dentry);
-		__ext4_fc_track_link(handle, old.inode, new.dentry);
-		__ext4_fc_track_unlink(handle, old.inode, old.dentry);
-		if (whiteout)
-			__ext4_fc_track_create(handle, whiteout, old.dentry);
+		if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
+		    !(EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY) &&
+		    !(ext4_test_mount_flag(sb, EXT4_MF_FC_INELIGIBLE))) {
+			__ext4_fc_track_link(handle, old.inode, new.dentry);
+			__ext4_fc_track_unlink(handle, old.inode, old.dentry);
+			if (whiteout)
+				__ext4_fc_track_create(handle, whiteout,
+						       old.dentry);
+		}
 	}
 
 	if (new.inode) {