Commit 
a53f4f8e9c8eb ("btrfs: Don't call btrfs_start_transaction() on
frozen fs to avoid deadlock.") started using internal calls and we
replace them with more suitable ones.
Signed-off-by: Rakesh Pandit <rakesh@tuxera.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
                         * happens. The pending operations are delayed to the
                         * next commit after thawing.
                         */
-                       if (__sb_start_write(sb, SB_FREEZE_WRITE, false))
-                               __sb_end_write(sb, SB_FREEZE_WRITE);
+                       if (sb_start_write_trylock(sb))
+                               sb_end_write(sb);
                        else
                                return 0;
                        trans = btrfs_start_transaction(root, 0);