f2fs: fix to avoid changing 'check only' behaior of recovery

The following two 'check only recovery' processes are very dependent on
the return value of f2fs_recover_fsync_data, especially when the return
value is greater than 0.
1. when device has readonly mode, shown as commit
23738e7 ("f2fs: fix to restrict mount condition on readonly block device")
2. mount optiont NORECOVERY or DISABLE_ROLL_FORWARD is set, shown as commit
6781eab ("f2fs: give -EINVAL for norecovery and rw mount")

However, commit c426d99 ("f2fs: Check write pointer consistency of open zones")
will change the return value unexpectedly, thereby changing the caller's behavior

This patch let the f2fs_recover_fsync_data return correct value,and not do
f2fs_check_and_fix_write_pointer when the device is read-only.

Fixes: c426d99 ("f2fs: Check write pointer consistency of open zones")
Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/recovery.c

@@ -899,10 +899,8 @@ int f2fs_recover_fsync_data(struct f2fs_sb_info *sbi, bool check_only)
 	 * and the f2fs is not read only, check and fix zoned block devices'
 	 * write pointer consistency.
 	 */
-	if (!err) {
+	if (!err)
 		err = f2fs_check_and_fix_write_pointer(sbi);
-		ret = err;
-	}
 
 	if (!err)
 		clear_sbi_flag(sbi, SBI_POR_DOING);

fs/f2fs/segment.c

@@ -5462,7 +5462,8 @@ int f2fs_check_and_fix_write_pointer(struct f2fs_sb_info *sbi)
 {
 	int ret;
 
-	if (!f2fs_sb_has_blkzoned(sbi) || f2fs_readonly(sbi->sb))
+	if (!f2fs_sb_has_blkzoned(sbi) || f2fs_readonly(sbi->sb) ||
+	    f2fs_hw_is_readonly(sbi))
 		return 0;
 
 	f2fs_notice(sbi, "Checking entire write pointers");