Linux-libre 4.3.2-gnu

1 files changed, 98 insertions, 43 deletions

diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 3da9f4da4..dc40a6d5a 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -164,7 +164,7 @@ xfs_ilock(
 	       (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
 	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
-	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
+	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
 
 	if (lock_flags & XFS_IOLOCK_EXCL)
 		mrupdate_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags));
@@ -212,7 +212,7 @@ xfs_ilock_nowait(
 	       (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
 	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
-	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
+	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
 
 	if (lock_flags & XFS_IOLOCK_EXCL) {
 		if (!mrtryupdate(&ip->i_iolock))
@@ -281,7 +281,7 @@ xfs_iunlock(
 	       (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
 	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
-	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
+	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
 	ASSERT(lock_flags != 0);
 
 	if (lock_flags & XFS_IOLOCK_EXCL)
@@ -363,31 +363,57 @@ int xfs_lock_delays;
 #endif
 
 /*
+ * xfs_lockdep_subclass_ok() is only used in an ASSERT, so is only called when
+ * DEBUG or XFS_WARN is set. And MAX_LOCKDEP_SUBCLASSES is then only defined
+ * when CONFIG_LOCKDEP is set. Hence the complex define below to avoid build
+ * errors and warnings.
+ */
+#if (defined(DEBUG) || defined(XFS_WARN)) && defined(CONFIG_LOCKDEP)
+static bool
+xfs_lockdep_subclass_ok(
+	int subclass)
+{
+	return subclass < MAX_LOCKDEP_SUBCLASSES;
+}
+#else
+#define xfs_lockdep_subclass_ok(subclass)	(true)
+#endif
+
+/*
  * Bump the subclass so xfs_lock_inodes() acquires each lock with a different
- * value. This shouldn't be called for page fault locking, but we also need to
- * ensure we don't overrun the number of lockdep subclasses for the iolock or
- * mmaplock as that is limited to 12 by the mmap lock lockdep annotations.
+ * value. This can be called for any type of inode lock combination, including
+ * parent locking. Care must be taken to ensure we don't overrun the subclass
+ * storage fields in the class mask we build.
  */
 static inline int
 xfs_lock_inumorder(int lock_mode, int subclass)
 {
+	int	class = 0;
+
+	ASSERT(!(lock_mode & (XFS_ILOCK_PARENT | XFS_ILOCK_RTBITMAP |
+			      XFS_ILOCK_RTSUM)));
+	ASSERT(xfs_lockdep_subclass_ok(subclass));
+
 	if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) {
-		ASSERT(subclass + XFS_LOCK_INUMORDER <
-			(1 << (XFS_MMAPLOCK_SHIFT - XFS_IOLOCK_SHIFT)));
-		lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_IOLOCK_SHIFT;
+		ASSERT(subclass <= XFS_IOLOCK_MAX_SUBCLASS);
+		ASSERT(xfs_lockdep_subclass_ok(subclass +
+						XFS_IOLOCK_PARENT_VAL));
+		class += subclass << XFS_IOLOCK_SHIFT;
+		if (lock_mode & XFS_IOLOCK_PARENT)
+			class += XFS_IOLOCK_PARENT_VAL << XFS_IOLOCK_SHIFT;
 	}
 
 	if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) {
-		ASSERT(subclass + XFS_LOCK_INUMORDER <
-			(1 << (XFS_ILOCK_SHIFT - XFS_MMAPLOCK_SHIFT)));
-		lock_mode |= (subclass + XFS_LOCK_INUMORDER) <<
-							XFS_MMAPLOCK_SHIFT;
+		ASSERT(subclass <= XFS_MMAPLOCK_MAX_SUBCLASS);
+		class += subclass << XFS_MMAPLOCK_SHIFT;
 	}
 
-	if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL))
-		lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_ILOCK_SHIFT;
+	if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) {
+		ASSERT(subclass <= XFS_ILOCK_MAX_SUBCLASS);
+		class += subclass << XFS_ILOCK_SHIFT;
+	}
 
-	return lock_mode;
+	return (lock_mode & ~XFS_LOCK_SUBCLASS_MASK) | class;
 }
 
 /*
@@ -399,6 +425,11 @@ xfs_lock_inumorder(int lock_mode, int subclass)
  * transaction (such as truncate). This can result in deadlock since the long
  * running trans might need to wait for the inode we just locked in order to
  * push the tail and free space in the log.
+ *
+ * xfs_lock_inodes() can only be used to lock one type of lock at a time -
+ * the iolock, the mmaplock or the ilock, but not more than one at a time. If we
+ * lock more than one at a time, lockdep will report false positives saying we
+ * have violated locking orders.
  */
 void
 xfs_lock_inodes(
@@ -409,8 +440,29 @@ xfs_lock_inodes(
 	int		attempts = 0, i, j, try_lock;
 	xfs_log_item_t	*lp;
 
-	/* currently supports between 2 and 5 inodes */
+	/*
+	 * Currently supports between 2 and 5 inodes with exclusive locking.  We
+	 * support an arbitrary depth of locking here, but absolute limits on
+	 * inodes depend on the the type of locking and the limits placed by
+	 * lockdep annotations in xfs_lock_inumorder.  These are all checked by
+	 * the asserts.
+	 */
 	ASSERT(ips && inodes >= 2 && inodes <= 5);
+	ASSERT(lock_mode & (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL |
+			    XFS_ILOCK_EXCL));
+	ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED | XFS_MMAPLOCK_SHARED |
+			      XFS_ILOCK_SHARED)));
+	ASSERT(!(lock_mode & XFS_IOLOCK_EXCL) ||
+		inodes <= XFS_IOLOCK_MAX_SUBCLASS + 1);
+	ASSERT(!(lock_mode & XFS_MMAPLOCK_EXCL) ||
+		inodes <= XFS_MMAPLOCK_MAX_SUBCLASS + 1);
+	ASSERT(!(lock_mode & XFS_ILOCK_EXCL) ||
+		inodes <= XFS_ILOCK_MAX_SUBCLASS + 1);
+
+	if (lock_mode & XFS_IOLOCK_EXCL) {
+		ASSERT(!(lock_mode & (XFS_MMAPLOCK_EXCL | XFS_ILOCK_EXCL)));
+	} else if (lock_mode & XFS_MMAPLOCK_EXCL)
+		ASSERT(!(lock_mode & XFS_ILOCK_EXCL));
 
 	try_lock = 0;
 	i = 0;
@@ -629,30 +681,29 @@ xfs_lookup(
 {
 	xfs_ino_t		inum;
 	int			error;
-	uint			lock_mode;
 
 	trace_xfs_lookup(dp, name);
 
 	if (XFS_FORCED_SHUTDOWN(dp->i_mount))
 		return -EIO;
 
-	lock_mode = xfs_ilock_data_map_shared(dp);
+	xfs_ilock(dp, XFS_IOLOCK_SHARED);
 	error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
-	xfs_iunlock(dp, lock_mode);
-
 	if (error)
-		goto out;
+		goto out_unlock;
 
 	error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
 	if (error)
 		goto out_free_name;
 
+	xfs_iunlock(dp, XFS_IOLOCK_SHARED);
 	return 0;
 
 out_free_name:
 	if (ci_name)
 		kmem_free(ci_name->name);
-out:
+out_unlock:
+	xfs_iunlock(dp, XFS_IOLOCK_SHARED);
 	*ipp = NULL;
 	return error;
 }
@@ -787,7 +838,7 @@ xfs_ialloc(
 
 	if (ip->i_d.di_version == 3) {
 		ASSERT(ip->i_d.di_ino == ino);
-		ASSERT(uuid_equal(&ip->i_d.di_uuid, &mp->m_sb.sb_uuid));
+		ASSERT(uuid_equal(&ip->i_d.di_uuid, &mp->m_sb.sb_meta_uuid));
 		ip->i_d.di_crc = 0;
 		ip->i_d.di_changecount = 1;
 		ip->i_d.di_lsn = 0;
@@ -1149,7 +1200,8 @@ xfs_create(
 		goto out_trans_cancel;
 
 
-	xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
+	xfs_ilock(dp, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL |
+		      XFS_IOLOCK_PARENT | XFS_ILOCK_PARENT);
 	unlock_dp_on_error = true;
 
 	xfs_bmap_init(&free_list, &first_block);
@@ -1175,11 +1227,8 @@ xfs_create(
 	 */
 	error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev,
 			       prid, resblks > 0, &ip, &committed);
-	if (error) {
-		if (error == -ENOSPC)
-			goto out_trans_cancel;
+	if (error)
 		goto out_trans_cancel;
-	}
 
 	/*
 	 * Now we join the directory inode to the transaction.  We do not do it
@@ -1188,7 +1237,7 @@ xfs_create(
 	 * the transaction cancel unlocking dp so don't do it explicitly in the
 	 * error path.
 	 */
-	xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
+	xfs_trans_ijoin(tp, dp, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
 	unlock_dp_on_error = false;
 
 	error = xfs_dir_createname(tp, dp, name, ip->i_ino,
@@ -1261,7 +1310,7 @@ xfs_create(
 	xfs_qm_dqrele(pdqp);
 
 	if (unlock_dp_on_error)
-		xfs_iunlock(dp, XFS_ILOCK_EXCL);
+		xfs_iunlock(dp, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
 	return error;
 }
 
@@ -1318,11 +1367,8 @@ xfs_create_tmpfile(
 
 	error = xfs_dir_ialloc(&tp, dp, mode, 1, 0,
 				prid, resblks > 0, &ip, NULL);
-	if (error) {
-		if (error == -ENOSPC)
-			goto out_trans_cancel;
+	if (error)
 		goto out_trans_cancel;
-	}
 
 	if (mp->m_flags & XFS_MOUNT_WSYNC)
 		xfs_trans_set_sync(tp);
@@ -1409,10 +1455,11 @@ xfs_link(
 	if (error)
 		goto error_return;
 
+	xfs_ilock(tdp, XFS_IOLOCK_EXCL | XFS_IOLOCK_PARENT);
 	xfs_lock_two_inodes(sip, tdp, XFS_ILOCK_EXCL);
 
 	xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL);
-	xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL);
+	xfs_trans_ijoin(tp, tdp, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
 
 	/*
 	 * If we are using project inheritance, we only allow hard link
@@ -1791,14 +1838,15 @@ xfs_inactive_ifree(
 	xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
 
 	/*
-	 * Just ignore errors at this point.  There is nothing we can
-	 * do except to try to keep going. Make sure it's not a silent
-	 * error.
+	 * Just ignore errors at this point.  There is nothing we can do except
+	 * to try to keep going. Make sure it's not a silent error.
 	 */
 	error = xfs_bmap_finish(&tp,  &free_list, &committed);
-	if (error)
+	if (error) {
 		xfs_notice(mp, "%s: xfs_bmap_finish returned error %d",
 			__func__, error);
+		xfs_bmap_cancel(&free_list);
+	}
 	error = xfs_trans_commit(tp);
 	if (error)
 		xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
@@ -2515,9 +2563,10 @@ xfs_remove(
 		goto out_trans_cancel;
 	}
 
+	xfs_ilock(dp, XFS_IOLOCK_EXCL | XFS_IOLOCK_PARENT);
 	xfs_lock_two_inodes(dp, ip, XFS_ILOCK_EXCL);
 
-	xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
+	xfs_trans_ijoin(tp, dp, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
 	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 
 	/*
@@ -2898,6 +2947,12 @@ xfs_rename(
 	 * whether the target directory is the same as the source
 	 * directory, we can lock from 2 to 4 inodes.
 	 */
+	if (!new_parent)
+		xfs_ilock(src_dp, XFS_IOLOCK_EXCL | XFS_IOLOCK_PARENT);
+	else
+		xfs_lock_two_inodes(src_dp, target_dp,
+				    XFS_IOLOCK_EXCL | XFS_IOLOCK_PARENT);
+
 	xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
 
 	/*
@@ -2905,9 +2960,9 @@ xfs_rename(
 	 * we can rely on either trans_commit or trans_cancel to unlock
 	 * them.
 	 */
-	xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
+	xfs_trans_ijoin(tp, src_dp, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
 	if (new_parent)
-		xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
+		xfs_trans_ijoin(tp, target_dp, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
 	xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
 	if (target_ip)
 		xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);