Merge tag 'xfs-5.1-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs fixes from Darrick Wong:
 "Here are a few fixes for some corruption bugs and uninitialized
  variable problems. The few patches here have gone through a few days
  worth of fstest runs with no new problems observed.

  Changes since last update:

   - Fix a bunch of static checker complaints about uninitialized
     variables and insufficient range checks.

   - Avoid a crash when incore extent map data are corrupt.

   - Disallow FITRIM when we haven't recovered the log and know the
     metadata are stale.

   - Fix a data corruption when doing unaligned overlapping dio writes"

* tag 'xfs-5.1-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: serialize unaligned dio writes against all other dio writes
  xfs: prohibit fstrim in norecovery mode
  xfs: always init bma in xfs_bmapi_write
  xfs: fix btree scrub checking with regards to root-in-inode
  xfs: dabtree scrub needs to range-check level
  xfs: don't trip over uninitialized buffer on extent read of corrupted inode
diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index 48502cb..4637ae1 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -1191,7 +1191,10 @@ xfs_iread_extents(
 	 * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
 	 */
 	level = be16_to_cpu(block->bb_level);
-	ASSERT(level > 0);
+	if (unlikely(level == 0)) {
+		XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
+		return -EFSCORRUPTED;
+	}
 	pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes);
 	bno = be64_to_cpu(*pp);
 
@@ -4249,9 +4252,13 @@ xfs_bmapi_write(
 	struct xfs_bmbt_irec	*mval,		/* output: map values */
 	int			*nmap)		/* i/o: mval size/count */
 {
+	struct xfs_bmalloca	bma = {
+		.tp		= tp,
+		.ip		= ip,
+		.total		= total,
+	};
 	struct xfs_mount	*mp = ip->i_mount;
 	struct xfs_ifork	*ifp;
-	struct xfs_bmalloca	bma = { NULL };	/* args for xfs_bmap_alloc */
 	xfs_fileoff_t		end;		/* end of mapped file region */
 	bool			eof = false;	/* after the end of extents */
 	int			error;		/* error return */
@@ -4319,10 +4326,6 @@ xfs_bmapi_write(
 		eof = true;
 	if (!xfs_iext_peek_prev_extent(ifp, &bma.icur, &bma.prev))
 		bma.prev.br_startoff = NULLFILEOFF;
-	bma.tp = tp;
-	bma.ip = ip;
-	bma.total = total;
-	bma.datatype = 0;
 	bma.minleft = xfs_bmapi_minleft(tp, ip, whichfork);
 
 	n = 0;
diff --git a/fs/xfs/scrub/btree.c b/fs/xfs/scrub/btree.c
index 6f94d1f..117910d 100644
--- a/fs/xfs/scrub/btree.c
+++ b/fs/xfs/scrub/btree.c
@@ -415,8 +415,17 @@ xchk_btree_check_owner(
 	struct xfs_btree_cur	*cur = bs->cur;
 	struct check_owner	*co;
 
-	if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && bp == NULL)
+	/*
+	 * In theory, xfs_btree_get_block should only give us a null buffer
+	 * pointer for the root of a root-in-inode btree type, but we need
+	 * to check defensively here in case the cursor state is also screwed
+	 * up.
+	 */
+	if (bp == NULL) {
+		if (!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE))
+			xchk_btree_set_corrupt(bs->sc, bs->cur, level);
 		return 0;
+	}
 
 	/*
 	 * We want to cross-reference each btree block with the bnobt
diff --git a/fs/xfs/scrub/dabtree.c b/fs/xfs/scrub/dabtree.c
index f1260b4..90527b0 100644
--- a/fs/xfs/scrub/dabtree.c
+++ b/fs/xfs/scrub/dabtree.c
@@ -574,6 +574,11 @@ xchk_da_btree(
 		/* Drill another level deeper. */
 		blkno = be32_to_cpu(key->before);
 		level++;
+		if (level >= XFS_DA_NODE_MAXDEPTH) {
+			/* Too deep! */
+			xchk_da_set_corrupt(&ds, level - 1);
+			break;
+		}
 		ds.tree_level--;
 		error = xchk_da_btree_block(&ds, level, blkno);
 		if (error)
diff --git a/fs/xfs/xfs_discard.c b/fs/xfs/xfs_discard.c
index 93f07ed..9ee2a7d 100644
--- a/fs/xfs/xfs_discard.c
+++ b/fs/xfs/xfs_discard.c
@@ -161,6 +161,14 @@ xfs_ioc_trim(
 		return -EPERM;
 	if (!blk_queue_discard(q))
 		return -EOPNOTSUPP;
+
+	/*
+	 * We haven't recovered the log, so we cannot use our bnobt-guided
+	 * storage zapping commands.
+	 */
+	if (mp->m_flags & XFS_MOUNT_NORECOVERY)
+		return -EROFS;
+
 	if (copy_from_user(&range, urange, sizeof(range)))
 		return -EFAULT;
 
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 1f2e284..a7ceae9 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -529,18 +529,17 @@ xfs_file_dio_aio_write(
 	count = iov_iter_count(from);
 
 	/*
-	 * If we are doing unaligned IO, wait for all other IO to drain,
-	 * otherwise demote the lock if we had to take the exclusive lock
-	 * for other reasons in xfs_file_aio_write_checks.
+	 * If we are doing unaligned IO, we can't allow any other overlapping IO
+	 * in-flight at the same time or we risk data corruption. Wait for all
+	 * other IO to drain before we submit. If the IO is aligned, demote the
+	 * iolock if we had to take the exclusive lock in
+	 * xfs_file_aio_write_checks() for other reasons.
 	 */
 	if (unaligned_io) {
-		/* If we are going to wait for other DIO to finish, bail */
-		if (iocb->ki_flags & IOCB_NOWAIT) {
-			if (atomic_read(&inode->i_dio_count))
-				return -EAGAIN;
-		} else {
-			inode_dio_wait(inode);
-		}
+		/* unaligned dio always waits, bail */
+		if (iocb->ki_flags & IOCB_NOWAIT)
+			return -EAGAIN;
+		inode_dio_wait(inode);
 	} else if (iolock == XFS_IOLOCK_EXCL) {
 		xfs_ilock_demote(ip, XFS_IOLOCK_EXCL);
 		iolock = XFS_IOLOCK_SHARED;
@@ -548,6 +547,14 @@ xfs_file_dio_aio_write(
 
 	trace_xfs_file_direct_write(ip, count, iocb->ki_pos);
 	ret = iomap_dio_rw(iocb, from, &xfs_iomap_ops, xfs_dio_write_end_io);
+
+	/*
+	 * If unaligned, this is the only IO in-flight. If it has not yet
+	 * completed, wait on it before we release the iolock to prevent
+	 * subsequent overlapping IO.
+	 */
+	if (ret == -EIOCBQUEUED && unaligned_io)
+		inode_dio_wait(inode);
 out:
 	xfs_iunlock(ip, iolock);