[PATCH 1/2] xfs: annotate grabbing the realtime bitmap/summary locks in growfs

["Darrick J. Wong" <darrick.wong@oracle.com>]

From: Darrick J. Wong <darrick.wong@oracle.com>

Use XFS_ILOCK_RT{BITMAP,SUM} to annotate grabbing the rt bitmap and
summary locks when we grow the realtime volume, just like we do most
everywhere else.  This shuts up lockdep warnings about grabbing the
ILOCK class of locks recursively:

============================================
WARNING: possible recursive locking detected
5.9.0-rc4-djw #rc4 Tainted: G           O
--------------------------------------------
xfs_growfs/4841 is trying to acquire lock:
ffff888035acc230 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_ilock+0xac/0x1a0 [xfs]

but task is already holding lock:
ffff888035acedb0 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_ilock+0xac/0x1a0 [xfs]

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&xfs_nondir_ilock_class);
  lock(&xfs_nondir_ilock_class);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_rtalloc.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)


diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c
index f9119ba3e9d0..ede1baf31413 100644
--- a/fs/xfs/xfs_rtalloc.c
+++ b/fs/xfs/xfs_rtalloc.c
@@ -1024,7 +1024,7 @@ xfs_growfs_rt(
 		/*
 		 * Lock out other callers by grabbing the bitmap inode lock.
 		 */
-		xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL);
+		xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL | XFS_ILOCK_RTBITMAP);
 		xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
 		/*
 		 * Update the bitmap inode's size ondisk and incore.  We need
@@ -1038,7 +1038,7 @@ xfs_growfs_rt(
 		/*
 		 * Get the summary inode into the transaction.
 		 */
-		xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL);
+		xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL | XFS_ILOCK_RTSUM);
 		xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
 		/*
 		 * Update the summary inode's size.  We need to update the