Merge branch 'xfs-misc-fixes-for-4.3-2' into for-next

fs/xfs/libxfs/xfs_attr.c

@@ -139,6 +139,8 @@ xfs_attr_get(
 
 	args.value = value;
 	args.valuelen = *valuelenp;
+	/* Entirely possible to look up a name which doesn't exist */
+	args.op_flags = XFS_DA_OP_OKNOENT;
 
 	lock_mode = xfs_ilock_attr_map_shared(ip);
 	if (!xfs_inode_hasattr(ip))

fs/xfs/libxfs/xfs_da_btree.c

@@ -1822,6 +1822,7 @@ xfs_da3_path_shift(
 	struct xfs_da_args	*args;
 	struct xfs_da_node_entry *btree;
 	struct xfs_da3_icnode_hdr nodehdr;
+	struct xfs_buf		*bp;
 	xfs_dablk_t		blkno = 0;
 	int			level;
 	int			error;
@@ -1866,20 +1867,24 @@ xfs_da3_path_shift(
 	 */
 	for (blk++, level++; level < path->active; blk++, level++) {
 		/*
-		 * Release the old block.
-		 * (if it's dirty, trans won't actually let go)
+		 * Read the next child block into a local buffer.
 		 */
-		if (release)
-			xfs_trans_brelse(args->trans, blk->bp);
+		error = xfs_da3_node_read(args->trans, dp, blkno, -1, &bp,
+					  args->whichfork);
+		if (error)
+			return error;
 
 		/*
-		 * Read the next child block.
+		 * Release the old block (if it's dirty, the trans doesn't
+		 * actually let go) and swap the local buffer into the path
+		 * structure. This ensures failure of the above read doesn't set
+		 * a NULL buffer in an active slot in the path.
 		 */
+		if (release)
+			xfs_trans_brelse(args->trans, blk->bp);
 		blk->blkno = blkno;
-		error = xfs_da3_node_read(args->trans, dp, blkno, -1,
-					&blk->bp, args->whichfork);
-		if (error)
-			return error;
+		blk->bp = bp;
+
 		info = blk->bp->b_addr;
 		ASSERT(info->magic == cpu_to_be16(XFS_DA_NODE_MAGIC) ||
 		       info->magic == cpu_to_be16(XFS_DA3_NODE_MAGIC) ||

fs/xfs/libxfs/xfs_da_format.h

@@ -680,8 +680,15 @@ typedef struct xfs_attr_leaf_name_remote {
 typedef struct xfs_attr_leafblock {
 	xfs_attr_leaf_hdr_t	hdr;	/* constant-structure header block */
 	xfs_attr_leaf_entry_t	entries[1];	/* sorted on key, not name */
-	xfs_attr_leaf_name_local_t namelist;	/* grows from bottom of buf */
-	xfs_attr_leaf_name_remote_t valuelist;	/* grows from bottom of buf */
+	/*
+	 * The rest of the block contains the following structures after the
+	 * leaf entries, growing from the bottom up. The variables are never
+	 * referenced and definining them can actually make gcc optimize away
+	 * accesses to the 'entries' array above index 0 so don't do that.
+	 *
+	 * xfs_attr_leaf_name_local_t namelist;
+	 * xfs_attr_leaf_name_remote_t valuelist;
+	 */
 } xfs_attr_leafblock_t;
 
 /*

fs/xfs/libxfs/xfs_dir2.c

@@ -362,6 +362,7 @@ xfs_dir_lookup(
 	struct xfs_da_args *args;
 	int		rval;
 	int		v;		/* type-checking value */
+	int		lock_mode;
 
 	ASSERT(S_ISDIR(dp->i_d.di_mode));
 	XFS_STATS_INC(xs_dir_lookup);
@@ -387,6 +388,7 @@ xfs_dir_lookup(
 	if (ci_name)
 		args->op_flags |= XFS_DA_OP_CILOOKUP;
 
+	lock_mode = xfs_ilock_data_map_shared(dp);
 	if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
 		rval = xfs_dir2_sf_lookup(args);
 		goto out_check_rval;
@@ -419,6 +421,7 @@ out_check_rval:
 		}
 	}
 out_free:
+	xfs_iunlock(dp, lock_mode);
 	kmem_free(args);
 	return rval;
 }

fs/xfs/libxfs/xfs_dir2_data.c

@@ -252,7 +252,8 @@ xfs_dir3_data_reada_verify(
 		return;
 	case cpu_to_be32(XFS_DIR2_DATA_MAGIC):
 	case cpu_to_be32(XFS_DIR3_DATA_MAGIC):
-		xfs_dir3_data_verify(bp);
+		bp->b_ops = &xfs_dir3_data_buf_ops;
+		bp->b_ops->verify_read(bp);
 		return;
 	default:
 		xfs_buf_ioerror(bp, -EFSCORRUPTED);

fs/xfs/libxfs/xfs_sb.c

@@ -186,9 +186,6 @@ xfs_mount_validate_sb(
 	if (xfs_sb_version_hassparseinodes(sbp)) {
 		uint32_t	align;
 
-		xfs_alert(mp,
-	"EXPERIMENTAL sparse inode feature enabled. Use at your own risk!");
-
 		align = XFS_INODES_PER_CHUNK * sbp->sb_inodesize
 				>> sbp->sb_blocklog;
 		if (sbp->sb_inoalignmt != align) {

fs/xfs/xfs_dir2_readdir.c

@@ -171,6 +171,7 @@ xfs_dir2_block_getdents(
 	int			wantoff;	/* starting block offset */
 	xfs_off_t		cook;
 	struct xfs_da_geometry	*geo = args->geo;
+	int			lock_mode;
 
 	/*
 	 * If the block number in the offset is out of range, we're done.
@@ -178,7 +179,9 @@ xfs_dir2_block_getdents(
 	if (xfs_dir2_dataptr_to_db(geo, ctx->pos) > geo->datablk)
 		return 0;
 
+	lock_mode = xfs_ilock_data_map_shared(dp);
 	error = xfs_dir3_block_read(NULL, dp, &bp);
+	xfs_iunlock(dp, lock_mode);
 	if (error)
 		return error;
 
@@ -529,9 +532,12 @@ xfs_dir2_leaf_getdents(
 		 * current buffer, need to get another one.
 		 */
 		if (!bp || ptr >= (char *)bp->b_addr + geo->blksize) {
+			int	lock_mode;
 
+			lock_mode = xfs_ilock_data_map_shared(dp);
 			error = xfs_dir2_leaf_readbuf(args, bufsize, map_info,
 						      &curoff, &bp);
+			xfs_iunlock(dp, lock_mode);
 			if (error || !map_info->map_valid)
 				break;
 
@@ -653,7 +659,6 @@ xfs_readdir(
 	struct xfs_da_args	args = { NULL };
 	int			rval;
 	int			v;
-	uint			lock_mode;
 
 	trace_xfs_readdir(dp);
 
@@ -666,7 +671,7 @@ xfs_readdir(
 	args.dp = dp;
 	args.geo = dp->i_mount->m_dir_geo;
 
-	lock_mode = xfs_ilock_data_map_shared(dp);
+	xfs_ilock(dp, XFS_IOLOCK_SHARED);
 	if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
 		rval = xfs_dir2_sf_getdents(&args, ctx);
 	else if ((rval = xfs_dir2_isblock(&args, &v)))
@@ -675,7 +680,7 @@ xfs_readdir(
 		rval = xfs_dir2_block_getdents(&args, ctx);
 	else
 		rval = xfs_dir2_leaf_getdents(&args, ctx, bufsize);
-	xfs_iunlock(dp, lock_mode);
+	xfs_iunlock(dp, XFS_IOLOCK_SHARED);
 
 	return rval;
 }

fs/xfs/xfs_dquot.c

@@ -251,7 +251,7 @@ xfs_qm_init_dquot_blk(
 		d->dd_diskdq.d_id = cpu_to_be32(curid);
 		d->dd_diskdq.d_flags = type;
 		if (xfs_sb_version_hascrc(&mp->m_sb)) {
-			uuid_copy(&d->dd_uuid, &mp->m_sb.sb_uuid);
+			uuid_copy(&d->dd_uuid, &mp->m_sb.sb_meta_uuid);
 			xfs_update_cksum((char *)d, sizeof(struct xfs_dqblk),
 					 XFS_DQUOT_CRC_OFF);
 		}

fs/xfs/xfs_file.c

@@ -317,24 +317,33 @@ xfs_file_read_iter(
 		return -EIO;
 
 	/*
-	 * Locking is a bit tricky here. If we take an exclusive lock
-	 * for direct IO, we effectively serialise all new concurrent
-	 * read IO to this file and block it behind IO that is currently in
-	 * progress because IO in progress holds the IO lock shared. We only
-	 * need to hold the lock exclusive to blow away the page cache, so
-	 * only take lock exclusively if the page cache needs invalidation.
-	 * This allows the normal direct IO case of no page cache pages to
-	 * proceeed concurrently without serialisation.
+	 * Locking is a bit tricky here. If we take an exclusive lock for direct
+	 * IO, we effectively serialise all new concurrent read IO to this file
+	 * and block it behind IO that is currently in progress because IO in
+	 * progress holds the IO lock shared. We only need to hold the lock
+	 * exclusive to blow away the page cache, so only take lock exclusively
+	 * if the page cache needs invalidation. This allows the normal direct
+	 * IO case of no page cache pages to proceeed concurrently without
+	 * serialisation.
 	 */
 	xfs_rw_ilock(ip, XFS_IOLOCK_SHARED);
 	if ((ioflags & XFS_IO_ISDIRECT) && inode->i_mapping->nrpages) {
 		xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
 		xfs_rw_ilock(ip, XFS_IOLOCK_EXCL);
 
+		/*
+		 * The generic dio code only flushes the range of the particular
+		 * I/O. Because we take an exclusive lock here, this whole
+		 * sequence is considerably more expensive for us. This has a
+		 * noticeable performance impact for any file with cached pages,
+		 * even when outside of the range of the particular I/O.
+		 *
+		 * Hence, amortize the cost of the lock against a full file
+		 * flush and reduce the chances of repeated iolock cycles going
+		 * forward.
+		 */
 		if (inode->i_mapping->nrpages) {
-			ret = filemap_write_and_wait_range(
-							VFS_I(ip)->i_mapping,
-							pos, pos + size - 1);
+			ret = filemap_write_and_wait(VFS_I(ip)->i_mapping);
 			if (ret) {
 				xfs_rw_iunlock(ip, XFS_IOLOCK_EXCL);
 				return ret;
@@ -345,9 +354,7 @@ xfs_file_read_iter(
 			 * we fail to invalidate a page, but this should never
 			 * happen on XFS. Warn if it does fail.
 			 */
-			ret = invalidate_inode_pages2_range(VFS_I(ip)->i_mapping,
-					pos >> PAGE_CACHE_SHIFT,
-					(pos + size - 1) >> PAGE_CACHE_SHIFT);
+			ret = invalidate_inode_pages2(VFS_I(ip)->i_mapping);
 			WARN_ON_ONCE(ret);
 			ret = 0;
 		}
@@ -733,19 +740,19 @@ xfs_file_dio_aio_write(
 	pos = iocb->ki_pos;
 	end = pos + count - 1;
 
+	/*
+	 * See xfs_file_read_iter() for why we do a full-file flush here.
+	 */
 	if (mapping->nrpages) {
-		ret = filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
-						   pos, end);
+		ret = filemap_write_and_wait(VFS_I(ip)->i_mapping);
 		if (ret)
 			goto out;
 		/*
-		 * Invalidate whole pages. This can return an error if
-		 * we fail to invalidate a page, but this should never
-		 * happen on XFS. Warn if it does fail.
+		 * Invalidate whole pages. This can return an error if we fail
+		 * to invalidate a page, but this should never happen on XFS.
+		 * Warn if it does fail.
 		 */
-		ret = invalidate_inode_pages2_range(VFS_I(ip)->i_mapping,
-					pos >> PAGE_CACHE_SHIFT,
-					end >> PAGE_CACHE_SHIFT);
+		ret = invalidate_inode_pages2(VFS_I(ip)->i_mapping);
 		WARN_ON_ONCE(ret);
 		ret = 0;
 	}

fs/xfs/xfs_fsops.c

@@ -250,7 +250,7 @@ xfs_growfs_data_private(
 		agf->agf_freeblks = cpu_to_be32(tmpsize);
 		agf->agf_longest = cpu_to_be32(tmpsize);
 		if (xfs_sb_version_hascrc(&mp->m_sb))
-			uuid_copy(&agf->agf_uuid, &mp->m_sb.sb_uuid);
+			uuid_copy(&agf->agf_uuid, &mp->m_sb.sb_meta_uuid);
 
 		error = xfs_bwrite(bp);
 		xfs_buf_relse(bp);
@@ -273,7 +273,7 @@ xfs_growfs_data_private(
 		if (xfs_sb_version_hascrc(&mp->m_sb)) {
 			agfl->agfl_magicnum = cpu_to_be32(XFS_AGFL_MAGIC);
 			agfl->agfl_seqno = cpu_to_be32(agno);
-			uuid_copy(&agfl->agfl_uuid, &mp->m_sb.sb_uuid);
+			uuid_copy(&agfl->agfl_uuid, &mp->m_sb.sb_meta_uuid);
 		}
 
 		agfl_bno = XFS_BUF_TO_AGFL_BNO(mp, bp);
@@ -309,7 +309,7 @@ xfs_growfs_data_private(
 		agi->agi_newino = cpu_to_be32(NULLAGINO);
 		agi->agi_dirino = cpu_to_be32(NULLAGINO);
 		if (xfs_sb_version_hascrc(&mp->m_sb))
-			uuid_copy(&agi->agi_uuid, &mp->m_sb.sb_uuid);
+			uuid_copy(&agi->agi_uuid, &mp->m_sb.sb_meta_uuid);
 		if (xfs_sb_version_hasfinobt(&mp->m_sb)) {
 			agi->agi_free_root = cpu_to_be32(XFS_FIBT_BLOCK(mp));
 			agi->agi_free_level = cpu_to_be32(1);

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)
@@ -362,32 +362,52 @@ int xfs_lots_retries;
 int xfs_lock_delays;
 #endif
 
+#ifdef 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 +419,11 @@ 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 +434,29 @@ 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 +675,29 @@ 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 +832,7 @@ 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 +1194,8 @@ 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);
@@ -1185,7 +1231,7 @@ 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,
@@ -1258,7 +1304,7 @@ 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;
 }
 
@@ -1403,10 +1449,11 @@ 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
@@ -2510,9 +2557,10 @@ 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);
 
 	/*
@@ -2893,6 +2941,12 @@ 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);
 
 	/*
@@ -2900,9 +2954,9 @@ 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);

fs/xfs/xfs_inode.h

@@ -284,9 +284,9 @@ static inline int xfs_isiflocked(struct xfs_inode *ip)
  * Flags for lockdep annotations.
  *
  * XFS_LOCK_PARENT - for directory operations that require locking a
- * parent directory inode and a child entry inode.  The parent gets locked
- * with this flag so it gets a lockdep subclass of 1 and the child entry
- * lock will have a lockdep subclass of 0.
+ * parent directory inode and a child entry inode. IOLOCK requires nesting,
+ * MMAPLOCK does not support this class, ILOCK requires a single subclass
+ * to differentiate parent from child.
  *
  * XFS_LOCK_RTBITMAP/XFS_LOCK_RTSUM - the realtime device bitmap and summary
  * inodes do not participate in the normal lock order, and thus have their
@@ -295,30 +295,63 @@ static inline int xfs_isiflocked(struct xfs_inode *ip)
  * XFS_LOCK_INUMORDER - for locking several inodes at the some time
  * with xfs_lock_inodes().  This flag is used as the starting subclass
  * and each subsequent lock acquired will increment the subclass by one.
- * So the first lock acquired will have a lockdep subclass of 4, the
- * second lock will have a lockdep subclass of 5, and so on. It is
- * the responsibility of the class builder to shift this to the correct
- * portion of the lock_mode lockdep mask.
+ * However, MAX_LOCKDEP_SUBCLASSES == 8, which means we are greatly
+ * limited to the subclasses we can represent via nesting. We need at least
+ * 5 inodes nest depth for the ILOCK through rename, and we also have to support
+ * XFS_ILOCK_PARENT, which gives 6 subclasses. Then we have XFS_ILOCK_RTBITMAP
+ * and XFS_ILOCK_RTSUM, which are another 2 unique subclasses, so that's all
+ * 8 subclasses supported by lockdep.
+ *
+ * This also means we have to number the sub-classes in the lowest bits of
+ * the mask we keep, and we have to ensure we never exceed 3 bits of lockdep
+ * mask and we can't use bit-masking to build the subclasses. What a mess.
+ *
+ * Bit layout:
+ *
+ * Bit		Lock Region
+ * 16-19	XFS_IOLOCK_SHIFT dependencies
+ * 20-23	XFS_MMAPLOCK_SHIFT dependencies
+ * 24-31	XFS_ILOCK_SHIFT dependencies
+ *
+ * IOLOCK values
+ *
+ * 0-3		subclass value
+ * 4-7		PARENT subclass values
+ *
+ * MMAPLOCK values
+ *
+ * 0-3		subclass value
+ * 4-7		unused
+ *
+ * ILOCK values
+ * 0-4		subclass values
+ * 5		PARENT subclass (not nestable)
+ * 6		RTBITMAP subclass (not nestable)
+ * 7		RTSUM subclass (not nestable)
+ * 
  */
-#define XFS_LOCK_PARENT		1
-#define XFS_LOCK_RTBITMAP	2
-#define XFS_LOCK_RTSUM		3
-#define XFS_LOCK_INUMORDER	4
-
-#define XFS_IOLOCK_SHIFT	16
-#define	XFS_IOLOCK_PARENT	(XFS_LOCK_PARENT << XFS_IOLOCK_SHIFT)
-
-#define XFS_MMAPLOCK_SHIFT	20
-
-#define XFS_ILOCK_SHIFT		24
-#define	XFS_ILOCK_PARENT	(XFS_LOCK_PARENT << XFS_ILOCK_SHIFT)
-#define	XFS_ILOCK_RTBITMAP	(XFS_LOCK_RTBITMAP << XFS_ILOCK_SHIFT)
-#define	XFS_ILOCK_RTSUM		(XFS_LOCK_RTSUM << XFS_ILOCK_SHIFT)
-
-#define XFS_IOLOCK_DEP_MASK	0x000f0000
-#define XFS_MMAPLOCK_DEP_MASK	0x00f00000
-#define XFS_ILOCK_DEP_MASK	0xff000000
-#define XFS_LOCK_DEP_MASK	(XFS_IOLOCK_DEP_MASK | \
+#define XFS_IOLOCK_SHIFT		16
+#define XFS_IOLOCK_PARENT_VAL		4
+#define XFS_IOLOCK_MAX_SUBCLASS		(XFS_IOLOCK_PARENT_VAL - 1)
+#define XFS_IOLOCK_DEP_MASK		0x000f0000
+#define	XFS_IOLOCK_PARENT		(XFS_IOLOCK_PARENT_VAL << XFS_IOLOCK_SHIFT)
+
+#define XFS_MMAPLOCK_SHIFT		20
+#define XFS_MMAPLOCK_NUMORDER		0
+#define XFS_MMAPLOCK_MAX_SUBCLASS	3
+#define XFS_MMAPLOCK_DEP_MASK		0x00f00000
+
+#define XFS_ILOCK_SHIFT			24
+#define XFS_ILOCK_PARENT_VAL		5
+#define XFS_ILOCK_MAX_SUBCLASS		(XFS_ILOCK_PARENT_VAL - 1)
+#define XFS_ILOCK_RTBITMAP_VAL		6
+#define XFS_ILOCK_RTSUM_VAL		7
+#define XFS_ILOCK_DEP_MASK		0xff000000
+#define	XFS_ILOCK_PARENT		(XFS_ILOCK_PARENT_VAL << XFS_ILOCK_SHIFT)
+#define	XFS_ILOCK_RTBITMAP		(XFS_ILOCK_RTBITMAP_VAL << XFS_ILOCK_SHIFT)
+#define	XFS_ILOCK_RTSUM			(XFS_ILOCK_RTSUM_VAL << XFS_ILOCK_SHIFT)
+
+#define XFS_LOCK_SUBCLASS_MASK	(XFS_IOLOCK_DEP_MASK | \
 				 XFS_MMAPLOCK_DEP_MASK | \
 				 XFS_ILOCK_DEP_MASK)
 

fs/xfs/xfs_log_recover.c

@@ -1895,15 +1895,25 @@ xlog_recover_get_buf_lsn(
 		 */
 		goto recover_immediately;
 	case XFS_SB_MAGIC:
+		/*
+		 * superblock uuids are magic. We may or may not have a
+		 * sb_meta_uuid on disk, but it will be set in the in-core
+		 * superblock. We set the uuid pointer for verification
+		 * according to the superblock feature mask to ensure we check
+		 * the relevant UUID in the superblock.
+		 */
 		lsn = be64_to_cpu(((struct xfs_dsb *)blk)->sb_lsn);
-		uuid = &((struct xfs_dsb *)blk)->sb_uuid;
+		if (xfs_sb_version_hasmetauuid(&mp->m_sb))
+			uuid = &((struct xfs_dsb *)blk)->sb_meta_uuid;
+		else
+			uuid = &((struct xfs_dsb *)blk)->sb_uuid;
 		break;
 	default:
 		break;
 	}
 
 	if (lsn != (xfs_lsn_t)-1) {
-		if (!uuid_equal(&mp->m_sb.sb_uuid, uuid))
+		if (!uuid_equal(&mp->m_sb.sb_meta_uuid, uuid))
 			goto recover_immediately;
 		return lsn;
 	}

fs/xfs/xfs_super.c

@@ -1528,6 +1528,10 @@ xfs_fs_fill_super(
 		}
 	}
 
+	if (xfs_sb_version_hassparseinodes(&mp->m_sb))
+		xfs_alert(mp,
+	"EXPERIMENTAL sparse inode feature enabled. Use at your own risk!");
+
 	error = xfs_mountfs(mp);
 	if (error)
 		goto out_filestream_unmount;

fs/xfs/xfs_symlink.c

@@ -240,7 +240,8 @@ xfs_symlink(
 	if (error)
 		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;
 
 	/*
@@ -288,7 +289,7 @@ xfs_symlink(
 	 * 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;
 
 	/*
@@ -421,7 +422,7 @@ out_release_inode:
 	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;
 }