ext4: remove pointless sb_rdonly() checks from freezing code

ext4_freeze() and ext4_unfreeze() checks for sb_rdonly(). However this
check is pointless as VFS already checks for read-only filesystem before
calling filesystem specific methods. Remove the pointless checks.
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230616165109.21695-1-jack@suse.czSigned-off-by: Theodore Ts'o <tytso@mit.edu>

fs/ext4/super.c

@@ -6347,12 +6347,7 @@ static int ext4_sync_fs(struct super_block *sb, int wait)
 static int ext4_freeze(struct super_block *sb)
 {
 	int error = 0;
-	journal_t *journal;
-
-	if (sb_rdonly(sb))
-		return 0;
-
-	journal = EXT4_SB(sb)->s_journal;
+	journal_t *journal = EXT4_SB(sb)->s_journal;
 
 	if (journal) {
 		/* Now we set up the journal barrier. */
@@ -6386,7 +6381,7 @@ static int ext4_freeze(struct super_block *sb)
  */
 static int ext4_unfreeze(struct super_block *sb)
 {
-	if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
+	if (ext4_forced_shutdown(EXT4_SB(sb)))
 		return 0;
 
 	if (EXT4_SB(sb)->s_journal) {