xfs: factor and verify attr leaf reads

Some reads are not converted yet because it isn't obvious ahead of
time what the format of the block is going to be. Need to determine
how to tell if the first block in the tree is a node or leaf format
block. That will be done in later patches.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NPhil White <pwhite@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

fs/xfs/xfs_attr.c

@@ -903,11 +903,9 @@ xfs_attr_leaf_addname(xfs_da_args_t *args)
 	 */
 	dp = args->dp;
 	args->blkno = 0;
-	error = xfs_da_read_buf(args->trans, args->dp, args->blkno, -1, &bp,
-					     XFS_ATTR_FORK, NULL);
+	error = xfs_attr_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
 	if (error)
-		return(error);
-	ASSERT(bp != NULL);
+		return error;
 
 	/*
 	 * Look up the given attribute in the leaf block.  Figure out if
@@ -1031,12 +1029,12 @@ xfs_attr_leaf_addname(xfs_da_args_t *args)
 		 * Read in the block containing the "old" attr, then
 		 * remove the "old" attr from that block (neat, huh!)
 		 */
-		error = xfs_da_read_buf(args->trans, args->dp, args->blkno, -1,
-						     &bp, XFS_ATTR_FORK, NULL);
+		error = xfs_attr_leaf_read(args->trans, args->dp, args->blkno,
+					   -1, &bp);
 		if (error)
-			return(error);
-		ASSERT(bp != NULL);
-		(void)xfs_attr_leaf_remove(bp, args);
+			return error;
+
+		xfs_attr_leaf_remove(bp, args);
 
 		/*
 		 * If the result is small enough, shrink it all into the inode.
@@ -1100,20 +1098,17 @@ xfs_attr_leaf_removename(xfs_da_args_t *args)
 	 */
 	dp = args->dp;
 	args->blkno = 0;
-	error = xfs_da_read_buf(args->trans, args->dp, args->blkno, -1, &bp,
-					     XFS_ATTR_FORK, NULL);
-	if (error) {
-		return(error);
-	}
+	error = xfs_attr_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
+	if (error)
+		return error;
 
-	ASSERT(bp != NULL);
 	error = xfs_attr_leaf_lookup_int(bp, args);
 	if (error == ENOATTR) {
 		xfs_trans_brelse(args->trans, bp);
 		return(error);
 	}
 
-	(void)xfs_attr_leaf_remove(bp, args);
+	xfs_attr_leaf_remove(bp, args);
 
 	/*
 	 * If the result is small enough, shrink it all into the inode.
@@ -1158,11 +1153,9 @@ xfs_attr_leaf_get(xfs_da_args_t *args)
 	trace_xfs_attr_leaf_get(args);
 
 	args->blkno = 0;
-	error = xfs_da_read_buf(args->trans, args->dp, args->blkno, -1, &bp,
-					     XFS_ATTR_FORK, NULL);
+	error = xfs_attr_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
 	if (error)
-		return(error);
-	ASSERT(bp != NULL);
+		return error;
 
 	error = xfs_attr_leaf_lookup_int(bp, args);
 	if (error != EEXIST)  {
@@ -1183,25 +1176,15 @@ xfs_attr_leaf_get(xfs_da_args_t *args)
 STATIC int
 xfs_attr_leaf_list(xfs_attr_list_context_t *context)
 {
-	xfs_attr_leafblock_t *leaf;
 	int error;
 	struct xfs_buf *bp;
 
 	trace_xfs_attr_leaf_list(context);
 
 	context->cursor->blkno = 0;
-	error = xfs_da_read_buf(NULL, context->dp, 0, -1, &bp, XFS_ATTR_FORK,
-				NULL);
+	error = xfs_attr_leaf_read(NULL, context->dp, 0, -1, &bp);
 	if (error)
 		return XFS_ERROR(error);
-	ASSERT(bp != NULL);
-	leaf = bp->b_addr;
-	if (unlikely(leaf->hdr.info.magic != cpu_to_be16(XFS_ATTR_LEAF_MAGIC))) {
-		XFS_CORRUPTION_ERROR("xfs_attr_leaf_list", XFS_ERRLEVEL_LOW,
-				     context->dp->i_mount, leaf);
-		xfs_trans_brelse(NULL, bp);
-		return XFS_ERROR(EFSCORRUPTED);
-	}
 
 	error = xfs_attr_leaf_list_int(bp, context);
 	xfs_trans_brelse(NULL, bp);
@@ -1605,12 +1588,9 @@ xfs_attr_node_removename(xfs_da_args_t *args)
 		ASSERT(state->path.blk[0].bp);
 		state->path.blk[0].bp = NULL;
 
-		error = xfs_da_read_buf(args->trans, args->dp, 0, -1, &bp,
-						     XFS_ATTR_FORK, NULL);
+		error = xfs_attr_leaf_read(args->trans, args->dp, 0, -1, &bp);
 		if (error)
 			goto out;
-		ASSERT((((xfs_attr_leafblock_t *)bp->b_addr)->hdr.info.magic) ==
-		       cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
 
 		if ((forkoff = xfs_attr_shortform_allfit(bp, dp))) {
 			xfs_bmap_init(args->flist, args->firstblock);
@@ -1920,14 +1900,6 @@ xfs_attr_node_list(xfs_attr_list_context_t *context)
 	 */
 	for (;;) {
 		leaf = bp->b_addr;
-		if (unlikely(leaf->hdr.info.magic !=
-			     cpu_to_be16(XFS_ATTR_LEAF_MAGIC))) {
-			XFS_CORRUPTION_ERROR("xfs_attr_node_list(4)",
-					     XFS_ERRLEVEL_LOW,
-					     context->dp->i_mount, leaf);
-			xfs_trans_brelse(NULL, bp);
-			return(XFS_ERROR(EFSCORRUPTED));
-		}
 		error = xfs_attr_leaf_list_int(bp, context);
 		if (error) {
 			xfs_trans_brelse(NULL, bp);
@@ -1937,16 +1909,10 @@ xfs_attr_node_list(xfs_attr_list_context_t *context)
 			break;
 		cursor->blkno = be32_to_cpu(leaf->hdr.info.forw);
 		xfs_trans_brelse(NULL, bp);
-		error = xfs_da_read_buf(NULL, context->dp, cursor->blkno, -1,
-					      &bp, XFS_ATTR_FORK, NULL);
+		error = xfs_attr_leaf_read(NULL, context->dp, cursor->blkno, -1,
+					   &bp);
 		if (error)
-			return(error);
-		if (unlikely((bp == NULL))) {
-			XFS_ERROR_REPORT("xfs_attr_node_list(5)",
-					 XFS_ERRLEVEL_LOW,
-					 context->dp->i_mount);
-			return(XFS_ERROR(EFSCORRUPTED));
-		}
+			return error;
 	}
 	xfs_trans_brelse(NULL, bp);
 	return(0);

fs/xfs/xfs_attr_leaf.c

@@ -88,6 +88,36 @@ STATIC void xfs_attr_leaf_moveents(xfs_attr_leafblock_t *src_leaf,
 					 xfs_mount_t *mp);
 STATIC int xfs_attr_leaf_entsize(xfs_attr_leafblock_t *leaf, int index);
 
+static void
+xfs_attr_leaf_verify(
+	struct xfs_buf		*bp)
+{
+	struct xfs_mount	*mp = bp->b_target->bt_mount;
+	struct xfs_attr_leaf_hdr *hdr = bp->b_addr;
+	int			block_ok = 0;
+
+	block_ok = hdr->info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC);
+	if (!block_ok) {
+		XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, hdr);
+		xfs_buf_ioerror(bp, EFSCORRUPTED);
+	}
+
+	bp->b_iodone = NULL;
+	xfs_buf_ioend(bp, 0);
+}
+
+int
+xfs_attr_leaf_read(
+	struct xfs_trans	*tp,
+	struct xfs_inode	*dp,
+	xfs_dablk_t		bno,
+	xfs_daddr_t		mappedbno,
+	struct xfs_buf		**bpp)
+{
+	return xfs_da_read_buf(tp, dp, bno, mappedbno, bpp,
+					XFS_ATTR_FORK, xfs_attr_leaf_verify);
+}
+
 /*========================================================================
  * Namespace helper routines
  *========================================================================*/
@@ -870,11 +900,10 @@ xfs_attr_leaf_to_node(xfs_da_args_t *args)
 	error = xfs_da_grow_inode(args, &blkno);
 	if (error)
 		goto out;
-	error = xfs_da_read_buf(args->trans, args->dp, 0, -1, &bp1,
-					     XFS_ATTR_FORK, NULL);
+	error = xfs_attr_leaf_read(args->trans, args->dp, 0, -1, &bp1);
 	if (error)
 		goto out;
-	ASSERT(bp1 != NULL);
+
 	bp2 = NULL;
 	error = xfs_da_get_buf(args->trans, args->dp, blkno, -1, &bp2,
 					    XFS_ATTR_FORK);
@@ -1641,18 +1670,16 @@ xfs_attr_leaf_toosmall(xfs_da_state_t *state, int *action)
 			blkno = be32_to_cpu(info->back);
 		if (blkno == 0)
 			continue;
-		error = xfs_da_read_buf(state->args->trans, state->args->dp,
-					blkno, -1, &bp, XFS_ATTR_FORK, NULL);
+		error = xfs_attr_leaf_read(state->args->trans, state->args->dp,
+					blkno, -1, &bp);
 		if (error)
 			return(error);
-		ASSERT(bp != NULL);
 
 		leaf = (xfs_attr_leafblock_t *)info;
 		count  = be16_to_cpu(leaf->hdr.count);
 		bytes  = state->blocksize - (state->blocksize>>2);
 		bytes -= be16_to_cpu(leaf->hdr.usedbytes);
 		leaf = bp->b_addr;
-		ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
 		count += be16_to_cpu(leaf->hdr.count);
 		bytes -= be16_to_cpu(leaf->hdr.usedbytes);
 		bytes -= count * sizeof(xfs_attr_leaf_entry_t);
@@ -2518,15 +2545,11 @@ xfs_attr_leaf_clearflag(xfs_da_args_t *args)
 	/*
 	 * Set up the operation.
 	 */
-	error = xfs_da_read_buf(args->trans, args->dp, args->blkno, -1, &bp,
-					     XFS_ATTR_FORK, NULL);
-	if (error) {
+	error = xfs_attr_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
+	if (error)
 		return(error);
-	}
-	ASSERT(bp != NULL);
 
 	leaf = bp->b_addr;
-	ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
 	ASSERT(args->index < be16_to_cpu(leaf->hdr.count));
 	ASSERT(args->index >= 0);
 	entry = &leaf->entries[ args->index ];
@@ -2583,15 +2606,11 @@ xfs_attr_leaf_setflag(xfs_da_args_t *args)
 	/*
 	 * Set up the operation.
 	 */
-	error = xfs_da_read_buf(args->trans, args->dp, args->blkno, -1, &bp,
-					     XFS_ATTR_FORK, NULL);
-	if (error) {
+	error = xfs_attr_leaf_read(args->trans, args->dp, args->blkno, -1, &bp);
+	if (error)
 		return(error);
-	}
-	ASSERT(bp != NULL);
 
 	leaf = bp->b_addr;
-	ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
 	ASSERT(args->index < be16_to_cpu(leaf->hdr.count));
 	ASSERT(args->index >= 0);
 	entry = &leaf->entries[ args->index ];
@@ -2640,35 +2659,28 @@ xfs_attr_leaf_flipflags(xfs_da_args_t *args)
 	/*
 	 * Read the block containing the "old" attr
 	 */
-	error = xfs_da_read_buf(args->trans, args->dp, args->blkno, -1, &bp1,
-					     XFS_ATTR_FORK, NULL);
-	if (error) {
-		return(error);
-	}
-	ASSERT(bp1 != NULL);
+	error = xfs_attr_leaf_read(args->trans, args->dp, args->blkno, -1, &bp1);
+	if (error)
+		return error;
 
 	/*
 	 * Read the block containing the "new" attr, if it is different
 	 */
 	if (args->blkno2 != args->blkno) {
-		error = xfs_da_read_buf(args->trans, args->dp, args->blkno2,
-					-1, &bp2, XFS_ATTR_FORK, NULL);
-		if (error) {
-			return(error);
-		}
-		ASSERT(bp2 != NULL);
+		error = xfs_attr_leaf_read(args->trans, args->dp, args->blkno2,
+					   -1, &bp2);
+		if (error)
+			return error;
 	} else {
 		bp2 = bp1;
 	}
 
 	leaf1 = bp1->b_addr;
-	ASSERT(leaf1->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
 	ASSERT(args->index < be16_to_cpu(leaf1->hdr.count));
 	ASSERT(args->index >= 0);
 	entry1 = &leaf1->entries[ args->index ];
 
 	leaf2 = bp2->b_addr;
-	ASSERT(leaf2->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
 	ASSERT(args->index2 < be16_to_cpu(leaf2->hdr.count));
 	ASSERT(args->index2 >= 0);
 	entry2 = &leaf2->entries[ args->index2 ];

fs/xfs/xfs_attr_leaf.h

@@ -227,6 +227,9 @@ int	xfs_attr_leaf_to_shortform(struct xfs_buf *bp,
 int	xfs_attr_leaf_clearflag(struct xfs_da_args *args);
 int	xfs_attr_leaf_setflag(struct xfs_da_args *args);
 int	xfs_attr_leaf_flipflags(xfs_da_args_t *args);
+int	xfs_attr_leaf_read(struct xfs_trans *tp, struct xfs_inode *dp,
+			xfs_dablk_t bno, xfs_daddr_t mappedbno,
+			struct xfs_buf **bpp);
 
 /*
  * Routines used for growing the Btree.