xfs: move RT inode locking out of __xfs_bunmapi

__xfs_bunmapi is a bit of an odd place to lock the rtbitmap and rtsummary
inodes given that it is very high level code.  While this only looks ugly
right now, it will become a problem when supporting delayed allocations
for RT inodes as __xfs_bunmapi might end up deleting only delalloc extents
and thus never unlock the rt inodes.

Move the locking into xfs_bmap_del_extent_real just before the call to
xfs_rtfree_blocks instead and use a new flag in the transaction to ensure
that the locking happens only once.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>

diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index f529aa4071092460ef375a26bb8378a49b206a27..22d44627ec59938f45c726d94d02e1872998ae93 100644 (file)
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -5307,6 +5307,14 @@ xfs_bmap_del_extent_real(
                if (xfs_is_reflink_inode(ip) && whichfork == XFS_DATA_FORK) {
                        xfs_refcount_decrease_extent(tp, del);
                } else if (xfs_ifork_is_realtime(ip, whichfork)) {
+                       /*
+                        * Ensure the bitmap and summary inodes are locked
+                        * and joined to the transaction before modifying them.
+                        */
+                       if (!(tp->t_flags & XFS_TRANS_RTBITMAP_LOCKED)) {
+                               tp->t_flags |= XFS_TRANS_RTBITMAP_LOCKED;
+                               xfs_rtbitmap_lock(tp, mp);
+                       }
                        error = xfs_rtfree_blocks(tp, del->br_startblock,
                                        del->br_blockcount);
                } else {
@@ -5408,13 +5416,6 @@ __xfs_bunmapi(
        } else
                cur = NULL;
 
-       if (isrt) {
-               /*
-                * Synchronize by locking the realtime bitmap.
-                */
-               xfs_rtbitmap_lock(tp, mp);
-       }
-
        extno = 0;
        while (end != (xfs_fileoff_t)-1 && end >= start &&
               (nexts == 0 || extno < nexts)) {

diff --git a/fs/xfs/libxfs/xfs_shared.h b/fs/xfs/libxfs/xfs_shared.h
index f35640ad3e7fe4c7de37c87cca2ba27163a5c56e..34f104ed372c096ec45a76195b5ff497bf847ebb 100644 (file)
--- a/fs/xfs/libxfs/xfs_shared.h
+++ b/fs/xfs/libxfs/xfs_shared.h
@@ -137,6 +137,9 @@ void        xfs_log_get_max_trans_res(struct xfs_mount *mp,
  */
 #define XFS_TRANS_LOWMODE              (1u << 8)
 
+/* Transaction has locked the rtbitmap and rtsum inodes */
+#define XFS_TRANS_RTBITMAP_LOCKED      (1u << 9)
+
 /*
  * Field values for xfs_trans_mod_sb.
  */