Merge branch 'xfs-extent-list-locking-fixes' into for-next

A set of fixes which makes sure we are taking the ilock whenever accessing the
extent list.  This was associated with "Access to block zero" messages which
may result in extent list corruption.

1 files changed, 23 insertions, 12 deletions

diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index 82e0dab46ee5..f264616080ca 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -618,22 +618,27 @@ xfs_getbmap(
                 return XFS_ERROR(ENOMEM);
 
         xfs_ilock(ip, XFS_IOLOCK_SHARED);
-        if (whichfork == XFS_DATA_FORK && !(iflags & BMV_IF_DELALLOC)) {
-                if (ip->i_delayed_blks || XFS_ISIZE(ip) > ip->i_d.di_size) {
+        if (whichfork == XFS_DATA_FORK) {
+                if (!(iflags & BMV_IF_DELALLOC) &&
+                    (ip->i_delayed_blks || XFS_ISIZE(ip) > ip->i_d.di_size)) {
                         error = -filemap_write_and_wait(VFS_I(ip)->i_mapping);
                         if (error)
                                 goto out_unlock_iolock;
+
+                        /*
+                         * Even after flushing the inode, there can still be
+                         * delalloc blocks on the inode beyond EOF due to
+                         * speculative preallocation.  These are not removed
+                         * until the release function is called or the inode
+                         * is inactivated.  Hence we cannot assert here that
+                         * ip->i_delayed_blks == 0.
+                         */
                 }
-                /*
-                 * even after flushing the inode, there can still be delalloc
-                 * blocks on the inode beyond EOF due to speculative
-                 * preallocation. These are not removed until the release
-                 * function is called or the inode is inactivated. Hence we
-                 * cannot assert here that ip->i_delayed_blks == 0.
-                 */
-        }
 
-        lock = xfs_ilock_map_shared(ip);
+                lock = xfs_ilock_data_map_shared(ip);
+        } else {
+                lock = xfs_ilock_attr_map_shared(ip);
+        }
 
         /*
          * Don't let nex be bigger than the number of extents
@@ -738,7 +743,7 @@ xfs_getbmap(
  out_free_map:
         kmem_free(map);
  out_unlock_ilock:
-        xfs_iunlock_map_shared(ip, lock);
+        xfs_iunlock(ip, lock);
  out_unlock_iolock:
         xfs_iunlock(ip, XFS_IOLOCK_SHARED);
 
@@ -1169,9 +1174,15 @@ xfs_zero_remaining_bytes(
         xfs_buf_unlock(bp);
 
         for (offset = startoff; offset <= endoff; offset = lastoffset + 1) {
+                uint lock_mode;
+
                 offset_fsb = XFS_B_TO_FSBT(mp, offset);
                 nimap = 1;
+
+                lock_mode = xfs_ilock_data_map_shared(ip);
                 error = xfs_bmapi_read(ip, offset_fsb, 1, &imap, &nimap, 0);
+                xfs_iunlock(ip, lock_mode);
+
                 if (error || nimap < 1)
                         break;
                 ASSERT(imap.br_blockcount >= 1);