Commit message: xfs: fix directory hash ordering bug

Commit f5ea1100 ("xfs: add CRCs to dir2/da node blocks") introduced
in 3.10 incorrectly converted the btree hash index array pointer in
xfs_da3_fixhashpath(). It resulted in the the current hash always
being compared against the first entry in the btree rather than the
current block index into the btree block's hash entry array. As a
result, it was comparing the wrong hashes, and so could misorder the
entries in the btree.

For most cases, this doesn't cause any problems as it requires hash
collisions to expose the ordering problem. However, when there are
hash collisions within a directory there is a very good probability
that the entries will be ordered incorrectly and that actually
matters when duplicate hashes are placed into or removed from the
btree block hash entry array.

This bug results in an on-disk directory corruption and that results
in directory verifier functions throwing corruption warnings into
the logs. While no data or directory entries are lost, access to
them may be compromised, and attempts to remove entries from a
directory that has suffered from this corruption may result in a
filesystem shutdown.  xfs_repair will fix the directory hash
ordering without data loss occuring.

[dchinner: wrote useful a commit message]

cc: <stable@vger.kernel.org>
Reported-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
CVE: CVE-2014-7283
CWE: CWE-399
Vulnerability description: The xfs_da3_fixhashpath function in fs/xfs/xfs_da_btree.c in the xfs implementation in the Linux kernel before 3.14.2 does not properly compare btree hash values, which allows local users to cause a denial of service (filesystem corruption, and OOPS or panic) via operations on directories that have hash collisions, as demonstrated by rmdir operations.

Project: linux
File: xfs_da_btree.c

xfs_da3_blk_link(
	struct xfs_da_state	*state,
	struct xfs_da_state_blk	*old_blk,
	struct xfs_da_state_blk	*new_blk)
{
	struct xfs_da_blkinfo	*old_info;
	struct xfs_da_blkinfo	*new_info;
	struct xfs_da_blkinfo	*tmp_info;
	struct xfs_da_args	*args;
	struct xfs_buf		*bp;
	int			before = 0;
	int			error;
	struct xfs_inode	*dp = state->args->dp;

	/*
	 * Set up environment.
	 */
	args = state->args;
	ASSERT(args != NULL);
	old_info = old_blk->bp->b_addr;
	new_info = new_blk->bp->b_addr;
	ASSERT(old_blk->magic == XFS_DA_NODE_MAGIC ||
	       old_blk->magic == XFS_DIR2_LEAFN_MAGIC ||
	       old_blk->magic == XFS_ATTR_LEAF_MAGIC);

	switch (old_blk->magic) {
	case XFS_ATTR_LEAF_MAGIC:
		before = xfs_attr_leaf_order(old_blk->bp, new_blk->bp);
		break;
	case XFS_DIR2_LEAFN_MAGIC:
		before = xfs_dir2_leafn_order(dp, old_blk->bp, new_blk->bp);
		break;
	case XFS_DA_NODE_MAGIC:
		before = xfs_da3_node_order(dp, old_blk->bp, new_blk->bp);
		break;
	}

	/*
	 * Link blocks in appropriate order.
	 */
	if (before) {
		/*
		 * Link new block in before existing block.
		 */
		trace_xfs_da_link_before(args);
		new_info->forw = cpu_to_be32(old_blk->blkno);
		new_info->back = old_info->back;
		if (old_info->back) {
			error = xfs_da3_node_read(args->trans, dp,
						be32_to_cpu(old_info->back),
						-1, &bp, args->whichfork);
			if (error)
				return(error);
			ASSERT(bp != NULL);
			tmp_info = bp->b_addr;
			ASSERT(tmp_info->magic == old_info->magic);
			ASSERT(be32_to_cpu(tmp_info->forw) == old_blk->blkno);
			tmp_info->forw = cpu_to_be32(new_blk->blkno);
			xfs_trans_log_buf(args->trans, bp, 0, sizeof(*tmp_info)-1);
		}
		old_info->back = cpu_to_be32(new_blk->blkno);
	} else {
		/*
		 * Link new block in after existing block.
		 */
		trace_xfs_da_link_after(args);
		new_info->forw = old_info->forw;
		new_info->back = cpu_to_be32(old_blk->blkno);
		if (old_info->forw) {
			error = xfs_da3_node_read(args->trans, dp,
						be32_to_cpu(old_info->forw),
						-1, &bp, args->whichfork);
			if (error)
				return(error);
			ASSERT(bp != NULL);
			tmp_info = bp->b_addr;
			ASSERT(tmp_info->magic == old_info->magic);
			ASSERT(be32_to_cpu(tmp_info->back) == old_blk->blkno);
			tmp_info->back = cpu_to_be32(new_blk->blkno);
			xfs_trans_log_buf(args->trans, bp, 0, sizeof(*tmp_info)-1);
		}
		old_info->forw = cpu_to_be32(new_blk->blkno);
	}

	xfs_trans_log_buf(args->trans, old_blk->bp, 0, sizeof(*tmp_info) - 1);
	xfs_trans_log_buf(args->trans, new_blk->bp, 0, sizeof(*tmp_info) - 1);
	return(0);
}

Project: linux
File: xfs_da_btree.c

xfs_da3_blk_unlink(
	struct xfs_da_state	*state,
	struct xfs_da_state_blk	*drop_blk,
	struct xfs_da_state_blk	*save_blk)
{
	struct xfs_da_blkinfo	*drop_info;
	struct xfs_da_blkinfo	*save_info;
	struct xfs_da_blkinfo	*tmp_info;
	struct xfs_da_args	*args;
	struct xfs_buf		*bp;
	int			error;

	/*
	 * Set up environment.
	 */
	args = state->args;
	ASSERT(args != NULL);
	save_info = save_blk->bp->b_addr;
	drop_info = drop_blk->bp->b_addr;
	ASSERT(save_blk->magic == XFS_DA_NODE_MAGIC ||
	       save_blk->magic == XFS_DIR2_LEAFN_MAGIC ||
	       save_blk->magic == XFS_ATTR_LEAF_MAGIC);
	ASSERT(save_blk->magic == drop_blk->magic);
	ASSERT((be32_to_cpu(save_info->forw) == drop_blk->blkno) ||
	       (be32_to_cpu(save_info->back) == drop_blk->blkno));
	ASSERT((be32_to_cpu(drop_info->forw) == save_blk->blkno) ||
	       (be32_to_cpu(drop_info->back) == save_blk->blkno));

	/*
	 * Unlink the leaf block from the doubly linked chain of leaves.
	 */
	if (be32_to_cpu(save_info->back) == drop_blk->blkno) {
		trace_xfs_da_unlink_back(args);
		save_info->back = drop_info->back;
		if (drop_info->back) {
			error = xfs_da3_node_read(args->trans, args->dp,
						be32_to_cpu(drop_info->back),
						-1, &bp, args->whichfork);
			if (error)
				return(error);
			ASSERT(bp != NULL);
			tmp_info = bp->b_addr;
			ASSERT(tmp_info->magic == save_info->magic);
			ASSERT(be32_to_cpu(tmp_info->forw) == drop_blk->blkno);
			tmp_info->forw = cpu_to_be32(save_blk->blkno);
			xfs_trans_log_buf(args->trans, bp, 0,
						    sizeof(*tmp_info) - 1);
		}
	} else {
		trace_xfs_da_unlink_forward(args);
		save_info->forw = drop_info->forw;
		if (drop_info->forw) {
			error = xfs_da3_node_read(args->trans, args->dp,
						be32_to_cpu(drop_info->forw),
						-1, &bp, args->whichfork);
			if (error)
				return(error);
			ASSERT(bp != NULL);
			tmp_info = bp->b_addr;
			ASSERT(tmp_info->magic == save_info->magic);
			ASSERT(be32_to_cpu(tmp_info->back) == drop_blk->blkno);
			tmp_info->back = cpu_to_be32(save_blk->blkno);
			xfs_trans_log_buf(args->trans, bp, 0,
						    sizeof(*tmp_info) - 1);
		}
	}

	xfs_trans_log_buf(args->trans, save_blk->bp, 0, sizeof(*save_info) - 1);
	return(0);
}

Project: linux
File: xfs_da_btree.c

xfs_da3_node_add(
	struct xfs_da_state	*state,
	struct xfs_da_state_blk	*oldblk,
	struct xfs_da_state_blk	*newblk)
{
	struct xfs_da_intnode	*node;
	struct xfs_da3_icnode_hdr nodehdr;
	struct xfs_da_node_entry *btree;
	int			tmp;
	struct xfs_inode	*dp = state->args->dp;

	trace_xfs_da_node_add(state->args);

	node = oldblk->bp->b_addr;
	dp->d_ops->node_hdr_from_disk(&nodehdr, node);
	btree = dp->d_ops->node_tree_p(node);

	ASSERT(oldblk->index >= 0 && oldblk->index <= nodehdr.count);
	ASSERT(newblk->blkno != 0);
	if (state->args->whichfork == XFS_DATA_FORK)
		ASSERT(newblk->blkno >= state->mp->m_dirleafblk &&
		       newblk->blkno < state->mp->m_dirfreeblk);

	/*
	 * We may need to make some room before we insert the new node.
	 */
	tmp = 0;
	if (oldblk->index < nodehdr.count) {
		tmp = (nodehdr.count - oldblk->index) * (uint)sizeof(*btree);
		memmove(&btree[oldblk->index + 1], &btree[oldblk->index], tmp);
	}
	btree[oldblk->index].hashval = cpu_to_be32(newblk->hashval);
	btree[oldblk->index].before = cpu_to_be32(newblk->blkno);
	xfs_trans_log_buf(state->args->trans, oldblk->bp,
		XFS_DA_LOGRANGE(node, &btree[oldblk->index],
				tmp + sizeof(*btree)));

	nodehdr.count += 1;
	dp->d_ops->node_hdr_to_disk(node, &nodehdr);
	xfs_trans_log_buf(state->args->trans, oldblk->bp,
		XFS_DA_LOGRANGE(node, &node->hdr, dp->d_ops->node_hdr_size));

	/*
	 * Copy the last hash value from the oldblk to propagate upwards.
	 */
	oldblk->hashval = be32_to_cpu(btree[nodehdr.count - 1].hashval);
}

Project: linux
File: xfs_da_btree.c

xfs_da3_node_create(
	struct xfs_da_args	*args,
	xfs_dablk_t		blkno,
	int			level,
	struct xfs_buf		**bpp,
	int			whichfork)
{
	struct xfs_da_intnode	*node;
	struct xfs_trans	*tp = args->trans;
	struct xfs_mount	*mp = tp->t_mountp;
	struct xfs_da3_icnode_hdr ichdr = {0};
	struct xfs_buf		*bp;
	int			error;
	struct xfs_inode	*dp = args->dp;

	trace_xfs_da_node_create(args);
	ASSERT(level <= XFS_DA_NODE_MAXDEPTH);

	error = xfs_da_get_buf(tp, dp, blkno, -1, &bp, whichfork);
	if (error)
		return(error);
	bp->b_ops = &xfs_da3_node_buf_ops;
	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DA_NODE_BUF);
	node = bp->b_addr;

	if (xfs_sb_version_hascrc(&mp->m_sb)) {
		struct xfs_da3_node_hdr *hdr3 = bp->b_addr;

		ichdr.magic = XFS_DA3_NODE_MAGIC;
		hdr3->info.blkno = cpu_to_be64(bp->b_bn);
		hdr3->info.owner = cpu_to_be64(args->dp->i_ino);
		uuid_copy(&hdr3->info.uuid, &mp->m_sb.sb_uuid);
	} else {
		ichdr.magic = XFS_DA_NODE_MAGIC;
	}
	ichdr.level = level;

	dp->d_ops->node_hdr_to_disk(node, &ichdr);
	xfs_trans_log_buf(tp, bp,
		XFS_DA_LOGRANGE(node, &node->hdr, dp->d_ops->node_hdr_size));

	*bpp = bp;
	return(0);
}

Project: linux
File: xfs_da_btree.c

xfs_da3_node_lasthash(
	struct xfs_inode	*dp,
	struct xfs_buf		*bp,
	int			*count)
{
	struct xfs_da_intnode	 *node;
	struct xfs_da_node_entry *btree;
	struct xfs_da3_icnode_hdr nodehdr;

	node = bp->b_addr;
	dp->d_ops->node_hdr_from_disk(&nodehdr, node);
	if (count)
		*count = nodehdr.count;
	if (!nodehdr.count)
		return 0;
	btree = dp->d_ops->node_tree_p(node);
	return be32_to_cpu(btree[nodehdr.count - 1].hashval);
}

Project: linux
File: xfs_da_btree.c

xfs_da3_node_lookup_int(
	struct xfs_da_state	*state,
	int			*result)
{
	struct xfs_da_state_blk	*blk;
	struct xfs_da_blkinfo	*curr;
	struct xfs_da_intnode	*node;
	struct xfs_da_node_entry *btree;
	struct xfs_da3_icnode_hdr nodehdr;
	struct xfs_da_args	*args;
	xfs_dablk_t		blkno;
	xfs_dahash_t		hashval;
	xfs_dahash_t		btreehashval;
	int			probe;
	int			span;
	int			max;
	int			error;
	int			retval;
	struct xfs_inode	*dp = state->args->dp;

	args = state->args;

	/*
	 * Descend thru the B-tree searching each level for the right
	 * node to use, until the right hashval is found.
	 */
	blkno = (args->whichfork == XFS_DATA_FORK)? state->mp->m_dirleafblk : 0;
	for (blk = &state->path.blk[0], state->path.active = 1;
			 state->path.active <= XFS_DA_NODE_MAXDEPTH;
			 blk++, state->path.active++) {
		/*
		 * Read the next node down in the tree.
		 */
		blk->blkno = blkno;
		error = xfs_da3_node_read(args->trans, args->dp, blkno,
					-1, &blk->bp, args->whichfork);
		if (error) {
			blk->blkno = 0;
			state->path.active--;
			return(error);
		}
		curr = blk->bp->b_addr;
		blk->magic = be16_to_cpu(curr->magic);

		if (blk->magic == XFS_ATTR_LEAF_MAGIC ||
		    blk->magic == XFS_ATTR3_LEAF_MAGIC) {
			blk->magic = XFS_ATTR_LEAF_MAGIC;
			blk->hashval = xfs_attr_leaf_lasthash(blk->bp, NULL);
			break;
		}

		if (blk->magic == XFS_DIR2_LEAFN_MAGIC ||
		    blk->magic == XFS_DIR3_LEAFN_MAGIC) {
			blk->magic = XFS_DIR2_LEAFN_MAGIC;
			blk->hashval = xfs_dir2_leafn_lasthash(args->dp,
							       blk->bp, NULL);
			break;
		}

		blk->magic = XFS_DA_NODE_MAGIC;


		/*
		 * Search an intermediate node for a match.
		 */
		node = blk->bp->b_addr;
		dp->d_ops->node_hdr_from_disk(&nodehdr, node);
		btree = dp->d_ops->node_tree_p(node);

		max = nodehdr.count;
		blk->hashval = be32_to_cpu(btree[max - 1].hashval);

		/*
		 * Binary search.  (note: small blocks will skip loop)
		 */
		probe = span = max / 2;
		hashval = args->hashval;
		while (span > 4) {
			span /= 2;
			btreehashval = be32_to_cpu(btree[probe].hashval);
			if (btreehashval < hashval)
				probe += span;
			else if (btreehashval > hashval)
				probe -= span;
			else
				break;
		}
		ASSERT((probe >= 0) && (probe < max));
		ASSERT((span <= 4) ||
			(be32_to_cpu(btree[probe].hashval) == hashval));

		/*
		 * Since we may have duplicate hashval's, find the first
		 * matching hashval in the node.
		 */
		while (probe > 0 &&
		       be32_to_cpu(btree[probe].hashval) >= hashval) {
			probe--;
		}
		while (probe < max &&
		       be32_to_cpu(btree[probe].hashval) < hashval) {
			probe++;
		}

		/*
		 * Pick the right block to descend on.
		 */
		if (probe == max) {
			blk->index = max - 1;
			blkno = be32_to_cpu(btree[max - 1].before);
		} else {
			blk->index = probe;
			blkno = be32_to_cpu(btree[probe].before);
		}
	}

	/*
	 * A leaf block that ends in the hashval that we are interested in
	 * (final hashval == search hashval) means that the next block may
	 * contain more entries with the same hashval, shift upward to the
	 * next leaf and keep searching.
	 */
	for (;;) {
		if (blk->magic == XFS_DIR2_LEAFN_MAGIC) {
			retval = xfs_dir2_leafn_lookup_int(blk->bp, args,
							&blk->index, state);
		} else if (blk->magic == XFS_ATTR_LEAF_MAGIC) {
			retval = xfs_attr3_leaf_lookup_int(blk->bp, args);
			blk->index = args->index;
			args->blkno = blk->blkno;
		} else {
			ASSERT(0);
			return XFS_ERROR(EFSCORRUPTED);
		}
		if (((retval == ENOENT) || (retval == ENOATTR)) &&
		    (blk->hashval == args->hashval)) {
			error = xfs_da3_path_shift(state, &state->path, 1, 1,
							 &retval);
			if (error)
				return(error);
			if (retval == 0) {
				continue;
			} else if (blk->magic == XFS_ATTR_LEAF_MAGIC) {
				/* path_shift() gives ENOENT */
				retval = XFS_ERROR(ENOATTR);
			}
		}
		break;
	}
	*result = retval;
	return(0);
}

Project: linux
File: xfs_da_btree.c

xfs_da3_node_order(
	struct xfs_inode *dp,
	struct xfs_buf	*node1_bp,
	struct xfs_buf	*node2_bp)
{
	struct xfs_da_intnode	*node1;
	struct xfs_da_intnode	*node2;
	struct xfs_da_node_entry *btree1;
	struct xfs_da_node_entry *btree2;
	struct xfs_da3_icnode_hdr node1hdr;
	struct xfs_da3_icnode_hdr node2hdr;

	node1 = node1_bp->b_addr;
	node2 = node2_bp->b_addr;
	dp->d_ops->node_hdr_from_disk(&node1hdr, node1);
	dp->d_ops->node_hdr_from_disk(&node2hdr, node2);
	btree1 = dp->d_ops->node_tree_p(node1);
	btree2 = dp->d_ops->node_tree_p(node2);

	if (node1hdr.count > 0 && node2hdr.count > 0 &&
	    ((be32_to_cpu(btree2[0].hashval) < be32_to_cpu(btree1[0].hashval)) ||
	     (be32_to_cpu(btree2[node2hdr.count - 1].hashval) <
	      be32_to_cpu(btree1[node1hdr.count - 1].hashval)))) {
		return 1;
	}
	return 0;
}

Project: linux
File: xfs_da_btree.c

xfs_da3_node_read(
	struct xfs_trans	*tp,
	struct xfs_inode	*dp,
	xfs_dablk_t		bno,
	xfs_daddr_t		mappedbno,
	struct xfs_buf		**bpp,
	int			which_fork)
{
	int			err;

	err = xfs_da_read_buf(tp, dp, bno, mappedbno, bpp,
					which_fork, &xfs_da3_node_buf_ops);
	if (!err && tp) {
		struct xfs_da_blkinfo	*info = (*bpp)->b_addr;
		int			type;

		switch (be16_to_cpu(info->magic)) {
		case XFS_DA_NODE_MAGIC:
		case XFS_DA3_NODE_MAGIC:
			type = XFS_BLFT_DA_NODE_BUF;
			break;
		case XFS_ATTR_LEAF_MAGIC:
		case XFS_ATTR3_LEAF_MAGIC:
			type = XFS_BLFT_ATTR_LEAF_BUF;
			break;
		case XFS_DIR2_LEAFN_MAGIC:
		case XFS_DIR3_LEAFN_MAGIC:
			type = XFS_BLFT_DIR_LEAFN_BUF;
			break;
		default:
			type = 0;
			ASSERT(0);
			break;
		}
		xfs_trans_buf_set_type(tp, *bpp, type);
	}
	return err;
}

Project: linux
File: xfs_da_btree.c

xfs_da3_node_read_verify(
	struct xfs_buf		*bp)
{
	struct xfs_mount	*mp = bp->b_target->bt_mount;
	struct xfs_da_blkinfo	*info = bp->b_addr;

	switch (be16_to_cpu(info->magic)) {
		case XFS_DA3_NODE_MAGIC:
			if (!xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
					      XFS_DA3_NODE_CRC_OFF))
				break;
			/* fall through */
		case XFS_DA_NODE_MAGIC:
			if (!xfs_da3_node_verify(bp))
				break;
			return;
		case XFS_ATTR_LEAF_MAGIC:
		case XFS_ATTR3_LEAF_MAGIC:
			bp->b_ops = &xfs_attr3_leaf_buf_ops;
			bp->b_ops->verify_read(bp);
			return;
		case XFS_DIR2_LEAFN_MAGIC:
		case XFS_DIR3_LEAFN_MAGIC:
			bp->b_ops = &xfs_dir3_leafn_buf_ops;
			bp->b_ops->verify_read(bp);
			return;
		default:
			break;
	}

	/* corrupt block */
	XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
	xfs_buf_ioerror(bp, EFSCORRUPTED);
}

Project: linux
File: xfs_da_btree.c

xfs_da3_node_remove(
	struct xfs_da_state	*state,
	struct xfs_da_state_blk	*drop_blk)
{
	struct xfs_da_intnode	*node;
	struct xfs_da3_icnode_hdr nodehdr;
	struct xfs_da_node_entry *btree;
	int			index;
	int			tmp;
	struct xfs_inode	*dp = state->args->dp;

	trace_xfs_da_node_remove(state->args);

	node = drop_blk->bp->b_addr;
	dp->d_ops->node_hdr_from_disk(&nodehdr, node);
	ASSERT(drop_blk->index < nodehdr.count);
	ASSERT(drop_blk->index >= 0);

	/*
	 * Copy over the offending entry, or just zero it out.
	 */
	index = drop_blk->index;
	btree = dp->d_ops->node_tree_p(node);
	if (index < nodehdr.count - 1) {
		tmp  = nodehdr.count - index - 1;
		tmp *= (uint)sizeof(xfs_da_node_entry_t);
		memmove(&btree[index], &btree[index + 1], tmp);
		xfs_trans_log_buf(state->args->trans, drop_blk->bp,
		    XFS_DA_LOGRANGE(node, &btree[index], tmp));
		index = nodehdr.count - 1;
	}
	memset(&btree[index], 0, sizeof(xfs_da_node_entry_t));
	xfs_trans_log_buf(state->args->trans, drop_blk->bp,
	    XFS_DA_LOGRANGE(node, &btree[index], sizeof(btree[index])));
	nodehdr.count -= 1;
	dp->d_ops->node_hdr_to_disk(node, &nodehdr);
	xfs_trans_log_buf(state->args->trans, drop_blk->bp,
	    XFS_DA_LOGRANGE(node, &node->hdr, dp->d_ops->node_hdr_size));

	/*
	 * Copy the last hash value from the block to propagate upwards.
	 */
	drop_blk->hashval = be32_to_cpu(btree[index - 1].hashval);
}

Project: linux
File: xfs_da_btree.c

xfs_da3_node_split(
	struct xfs_da_state	*state,
	struct xfs_da_state_blk	*oldblk,
	struct xfs_da_state_blk	*newblk,
	struct xfs_da_state_blk	*addblk,
	int			treelevel,
	int			*result)
{
	struct xfs_da_intnode	*node;
	struct xfs_da3_icnode_hdr nodehdr;
	xfs_dablk_t		blkno;
	int			newcount;
	int			error;
	int			useextra;
	struct xfs_inode	*dp = state->args->dp;

	trace_xfs_da_node_split(state->args);

	node = oldblk->bp->b_addr;
	dp->d_ops->node_hdr_from_disk(&nodehdr, node);

	/*
	 * With V2 dirs the extra block is data or freespace.
	 */
	useextra = state->extravalid && state->args->whichfork == XFS_ATTR_FORK;
	newcount = 1 + useextra;
	/*
	 * Do we have to split the node?
	 */
	if (nodehdr.count + newcount > state->node_ents) {
		/*
		 * Allocate a new node, add to the doubly linked chain of
		 * nodes, then move some of our excess entries into it.
		 */
		error = xfs_da_grow_inode(state->args, &blkno);
		if (error)
			return(error);	/* GROT: dir is inconsistent */

		error = xfs_da3_node_create(state->args, blkno, treelevel,
					   &newblk->bp, state->args->whichfork);
		if (error)
			return(error);	/* GROT: dir is inconsistent */
		newblk->blkno = blkno;
		newblk->magic = XFS_DA_NODE_MAGIC;
		xfs_da3_node_rebalance(state, oldblk, newblk);
		error = xfs_da3_blk_link(state, oldblk, newblk);
		if (error)
			return(error);
		*result = 1;
	} else {
		*result = 0;
	}

	/*
	 * Insert the new entry(s) into the correct block
	 * (updating last hashval in the process).
	 *
	 * xfs_da3_node_add() inserts BEFORE the given index,
	 * and as a result of using node_lookup_int() we always
	 * point to a valid entry (not after one), but a split
	 * operation always results in a new block whose hashvals
	 * FOLLOW the current block.
	 *
	 * If we had double-split op below us, then add the extra block too.
	 */
	node = oldblk->bp->b_addr;
	dp->d_ops->node_hdr_from_disk(&nodehdr, node);
	if (oldblk->index <= nodehdr.count) {
		oldblk->index++;
		xfs_da3_node_add(state, oldblk, addblk);
		if (useextra) {
			if (state->extraafter)
				oldblk->index++;
			xfs_da3_node_add(state, oldblk, &state->extrablk);
			state->extravalid = 0;
		}
	} else {
		newblk->index++;
		xfs_da3_node_add(state, newblk, addblk);
		if (useextra) {
			if (state->extraafter)
				newblk->index++;
			xfs_da3_node_add(state, newblk, &state->extrablk);
			state->extravalid = 0;
		}
	}

	return(0);
}

Project: linux
File: xfs_da_btree.c

xfs_da3_node_toosmall(
	struct xfs_da_state	*state,
	int			*action)
{
	struct xfs_da_intnode	*node;
	struct xfs_da_state_blk	*blk;
	struct xfs_da_blkinfo	*info;
	xfs_dablk_t		blkno;
	struct xfs_buf		*bp;
	struct xfs_da3_icnode_hdr nodehdr;
	int			count;
	int			forward;
	int			error;
	int			retval;
	int			i;
	struct xfs_inode	*dp = state->args->dp;

	trace_xfs_da_node_toosmall(state->args);

	/*
	 * Check for the degenerate case of the block being over 50% full.
	 * If so, it's not worth even looking to see if we might be able
	 * to coalesce with a sibling.
	 */
	blk = &state->path.blk[ state->path.active-1 ];
	info = blk->bp->b_addr;
	node = (xfs_da_intnode_t *)info;
	dp->d_ops->node_hdr_from_disk(&nodehdr, node);
	if (nodehdr.count > (state->node_ents >> 1)) {
		*action = 0;	/* blk over 50%, don't try to join */
		return(0);	/* blk over 50%, don't try to join */
	}

	/*
	 * Check for the degenerate case of the block being empty.
	 * If the block is empty, we'll simply delete it, no need to
	 * coalesce it with a sibling block.  We choose (arbitrarily)
	 * to merge with the forward block unless it is NULL.
	 */
	if (nodehdr.count == 0) {
		/*
		 * Make altpath point to the block we want to keep and
		 * path point to the block we want to drop (this one).
		 */
		forward = (info->forw != 0);
		memcpy(&state->altpath, &state->path, sizeof(state->path));
		error = xfs_da3_path_shift(state, &state->altpath, forward,
						 0, &retval);
		if (error)
			return(error);
		if (retval) {
			*action = 0;
		} else {
			*action = 2;
		}
		return(0);
	}

	/*
	 * Examine each sibling block to see if we can coalesce with
	 * at least 25% free space to spare.  We need to figure out
	 * whether to merge with the forward or the backward block.
	 * We prefer coalescing with the lower numbered sibling so as
	 * to shrink a directory over time.
	 */
	count  = state->node_ents;
	count -= state->node_ents >> 2;
	count -= nodehdr.count;

	/* start with smaller blk num */
	forward = nodehdr.forw < nodehdr.back;
	for (i = 0; i < 2; forward = !forward, i++) {
		struct xfs_da3_icnode_hdr thdr;
		if (forward)
			blkno = nodehdr.forw;
		else
			blkno = nodehdr.back;
		if (blkno == 0)
			continue;
		error = xfs_da3_node_read(state->args->trans, dp,
					blkno, -1, &bp, state->args->whichfork);
		if (error)
			return(error);

		node = bp->b_addr;
		dp->d_ops->node_hdr_from_disk(&thdr, node);
		xfs_trans_brelse(state->args->trans, bp);

		if (count - thdr.count >= 0)
			break;	/* fits with at least 25% to spare */
	}
	if (i >= 2) {
		*action = 0;
		return 0;
	}

	/*
	 * Make altpath point to the block we want to keep (the lower
	 * numbered block) and path point to the block we want to drop.
	 */
	memcpy(&state->altpath, &state->path, sizeof(state->path));
	if (blkno < blk->blkno) {
		error = xfs_da3_path_shift(state, &state->altpath, forward,
						 0, &retval);
	} else {
		error = xfs_da3_path_shift(state, &state->path, forward,
						 0, &retval);
	}
	if (error)
		return error;
	if (retval) {
		*action = 0;
		return 0;
	}
	*action = 1;
	return 0;
}

Project: linux
File: xfs_da_btree.c

xfs_da3_node_unbalance(
	struct xfs_da_state	*state,
	struct xfs_da_state_blk	*drop_blk,
	struct xfs_da_state_blk	*save_blk)
{
	struct xfs_da_intnode	*drop_node;
	struct xfs_da_intnode	*save_node;
	struct xfs_da_node_entry *drop_btree;
	struct xfs_da_node_entry *save_btree;
	struct xfs_da3_icnode_hdr drop_hdr;
	struct xfs_da3_icnode_hdr save_hdr;
	struct xfs_trans	*tp;
	int			sindex;
	int			tmp;
	struct xfs_inode	*dp = state->args->dp;

	trace_xfs_da_node_unbalance(state->args);

	drop_node = drop_blk->bp->b_addr;
	save_node = save_blk->bp->b_addr;
	dp->d_ops->node_hdr_from_disk(&drop_hdr, drop_node);
	dp->d_ops->node_hdr_from_disk(&save_hdr, save_node);
	drop_btree = dp->d_ops->node_tree_p(drop_node);
	save_btree = dp->d_ops->node_tree_p(save_node);
	tp = state->args->trans;

	/*
	 * If the dying block has lower hashvals, then move all the
	 * elements in the remaining block up to make a hole.
	 */
	if ((be32_to_cpu(drop_btree[0].hashval) <
			be32_to_cpu(save_btree[0].hashval)) ||
	    (be32_to_cpu(drop_btree[drop_hdr.count - 1].hashval) <
			be32_to_cpu(save_btree[save_hdr.count - 1].hashval))) {
		/* XXX: check this - is memmove dst correct? */
		tmp = save_hdr.count * sizeof(xfs_da_node_entry_t);
		memmove(&save_btree[drop_hdr.count], &save_btree[0], tmp);

		sindex = 0;
		xfs_trans_log_buf(tp, save_blk->bp,
			XFS_DA_LOGRANGE(save_node, &save_btree[0],
				(save_hdr.count + drop_hdr.count) *
						sizeof(xfs_da_node_entry_t)));
	} else {
		sindex = save_hdr.count;
		xfs_trans_log_buf(tp, save_blk->bp,
			XFS_DA_LOGRANGE(save_node, &save_btree[sindex],
				drop_hdr.count * sizeof(xfs_da_node_entry_t)));
	}

	/*
	 * Move all the B-tree elements from drop_blk to save_blk.
	 */
	tmp = drop_hdr.count * (uint)sizeof(xfs_da_node_entry_t);
	memcpy(&save_btree[sindex], &drop_btree[0], tmp);
	save_hdr.count += drop_hdr.count;

	dp->d_ops->node_hdr_to_disk(save_node, &save_hdr);
	xfs_trans_log_buf(tp, save_blk->bp,
		XFS_DA_LOGRANGE(save_node, &save_node->hdr,
				dp->d_ops->node_hdr_size));

	/*
	 * Save the last hashval in the remaining block for upward propagation.
	 */
	save_blk->hashval = be32_to_cpu(save_btree[save_hdr.count - 1].hashval);
}

Project: linux
File: xfs_da_btree.c

xfs_da3_node_verify(
	struct xfs_buf		*bp)
{
	struct xfs_mount	*mp = bp->b_target->bt_mount;
	struct xfs_da_intnode	*hdr = bp->b_addr;
	struct xfs_da3_icnode_hdr ichdr;
	const struct xfs_dir_ops *ops;

	ops = xfs_dir_get_ops(mp, NULL);

	ops->node_hdr_from_disk(&ichdr, hdr);

	if (xfs_sb_version_hascrc(&mp->m_sb)) {
		struct xfs_da3_node_hdr *hdr3 = bp->b_addr;

		if (ichdr.magic != XFS_DA3_NODE_MAGIC)
			return false;

		if (!uuid_equal(&hdr3->info.uuid, &mp->m_sb.sb_uuid))
			return false;
		if (be64_to_cpu(hdr3->info.blkno) != bp->b_bn)
			return false;
	} else {
		if (ichdr.magic != XFS_DA_NODE_MAGIC)
			return false;
	}
	if (ichdr.level == 0)
		return false;
	if (ichdr.level > XFS_DA_NODE_MAXDEPTH)
		return false;
	if (ichdr.count == 0)
		return false;

	/*
	 * we don't know if the node is for and attribute or directory tree,
	 * so only fail if the count is outside both bounds
	 */
	if (ichdr.count > mp->m_dir_node_ents &&
	    ichdr.count > mp->m_attr_node_ents)
		return false;

	/* XXX: hash order check? */

	return true;
}

Project: linux
File: xfs_da_btree.c

xfs_da3_node_write_verify(
	struct xfs_buf	*bp)
{
	struct xfs_mount	*mp = bp->b_target->bt_mount;
	struct xfs_buf_log_item	*bip = bp->b_fspriv;
	struct xfs_da3_node_hdr *hdr3 = bp->b_addr;

	if (!xfs_da3_node_verify(bp)) {
		XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
		xfs_buf_ioerror(bp, EFSCORRUPTED);
		return;
	}

	if (!xfs_sb_version_hascrc(&mp->m_sb))
		return;

	if (bip)
		hdr3->info.lsn = cpu_to_be64(bip->bli_item.li_lsn);

	xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length), XFS_DA3_NODE_CRC_OFF);
}

Project: linux
File: xfs_da_btree.c

xfs_da3_path_shift(
	struct xfs_da_state	*state,
	struct xfs_da_state_path *path,
	int			forward,
	int			release,
	int			*result)
{
	struct xfs_da_state_blk	*blk;
	struct xfs_da_blkinfo	*info;
	struct xfs_da_intnode	*node;
	struct xfs_da_args	*args;
	struct xfs_da_node_entry *btree;
	struct xfs_da3_icnode_hdr nodehdr;
	xfs_dablk_t		blkno = 0;
	int			level;
	int			error;
	struct xfs_inode	*dp = state->args->dp;

	trace_xfs_da_path_shift(state->args);

	/*
	 * Roll up the Btree looking for the first block where our
	 * current index is not at the edge of the block.  Note that
	 * we skip the bottom layer because we want the sibling block.
	 */
	args = state->args;
	ASSERT(args != NULL);
	ASSERT(path != NULL);
	ASSERT((path->active > 0) && (path->active < XFS_DA_NODE_MAXDEPTH));
	level = (path->active-1) - 1;	/* skip bottom layer in path */
	for (blk = &path->blk[level]; level >= 0; blk--, level--) {
		node = blk->bp->b_addr;
		dp->d_ops->node_hdr_from_disk(&nodehdr, node);
		btree = dp->d_ops->node_tree_p(node);

		if (forward && (blk->index < nodehdr.count - 1)) {
			blk->index++;
			blkno = be32_to_cpu(btree[blk->index].before);
			break;
		} else if (!forward && (blk->index > 0)) {
			blk->index--;
			blkno = be32_to_cpu(btree[blk->index].before);
			break;
		}
	}
	if (level < 0) {
		*result = XFS_ERROR(ENOENT);	/* we're out of our tree */
		ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
		return(0);
	}

	/*
	 * Roll down the edge of the subtree until we reach the
	 * same depth we were at originally.
	 */
	for (blk++, level++; level < path->active; blk++, level++) {
		/*
		 * Release the old block.
		 * (if it's dirty, trans won't actually let go)
		 */
		if (release)
			xfs_trans_brelse(args->trans, blk->bp);

		/*
		 * Read the next child block.
		 */
		blk->blkno = blkno;
		error = xfs_da3_node_read(args->trans, dp, blkno, -1,
					&blk->bp, args->whichfork);
		if (error)
			return(error);
		info = blk->bp->b_addr;
		ASSERT(info->magic == cpu_to_be16(XFS_DA_NODE_MAGIC) ||
		       info->magic == cpu_to_be16(XFS_DA3_NODE_MAGIC) ||
		       info->magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
		       info->magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC) ||
		       info->magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC) ||
		       info->magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC));


		/*
		 * Note: we flatten the magic number to a single type so we
		 * don't have to compare against crc/non-crc types elsewhere.
		 */
		switch (be16_to_cpu(info->magic)) {
		case XFS_DA_NODE_MAGIC:
		case XFS_DA3_NODE_MAGIC:
			blk->magic = XFS_DA_NODE_MAGIC;
			node = (xfs_da_intnode_t *)info;
			dp->d_ops->node_hdr_from_disk(&nodehdr, node);
			btree = dp->d_ops->node_tree_p(node);
			blk->hashval = be32_to_cpu(btree[nodehdr.count - 1].hashval);
			if (forward)
				blk->index = 0;
			else
				blk->index = nodehdr.count - 1;
			blkno = be32_to_cpu(btree[blk->index].before);
			break;
		case XFS_ATTR_LEAF_MAGIC:
		case XFS_ATTR3_LEAF_MAGIC:
			blk->magic = XFS_ATTR_LEAF_MAGIC;
			ASSERT(level == path->active-1);
			blk->index = 0;
			blk->hashval = xfs_attr_leaf_lasthash(blk->bp, NULL);
			break;
		case XFS_DIR2_LEAFN_MAGIC:
		case XFS_DIR3_LEAFN_MAGIC:
			blk->magic = XFS_DIR2_LEAFN_MAGIC;
			ASSERT(level == path->active-1);
			blk->index = 0;
			blk->hashval = xfs_dir2_leafn_lasthash(args->dp,
							       blk->bp, NULL);
			break;
		default:
			ASSERT(0);
			break;
		}
	}
	*result = 0;
	return 0;
}

Project: linux
File: xfs_da_btree.c

xfs_da3_root_join(
	struct xfs_da_state	*state,
	struct xfs_da_state_blk	*root_blk)
{
	struct xfs_da_intnode	*oldroot;
	struct xfs_da_args	*args;
	xfs_dablk_t		child;
	struct xfs_buf		*bp;
	struct xfs_da3_icnode_hdr oldroothdr;
	struct xfs_da_node_entry *btree;
	int			error;
	struct xfs_inode	*dp = state->args->dp;

	trace_xfs_da_root_join(state->args);

	ASSERT(root_blk->magic == XFS_DA_NODE_MAGIC);

	args = state->args;
	oldroot = root_blk->bp->b_addr;
	dp->d_ops->node_hdr_from_disk(&oldroothdr, oldroot);
	ASSERT(oldroothdr.forw == 0);
	ASSERT(oldroothdr.back == 0);

	/*
	 * If the root has more than one child, then don't do anything.
	 */
	if (oldroothdr.count > 1)
		return 0;

	/*
	 * Read in the (only) child block, then copy those bytes into
	 * the root block's buffer and free the original child block.
	 */
	btree = dp->d_ops->node_tree_p(oldroot);
	child = be32_to_cpu(btree[0].before);
	ASSERT(child != 0);
	error = xfs_da3_node_read(args->trans, dp, child, -1, &bp,
					     args->whichfork);
	if (error)
		return error;
	xfs_da_blkinfo_onlychild_validate(bp->b_addr, oldroothdr.level);

	/*
	 * This could be copying a leaf back into the root block in the case of
	 * there only being a single leaf block left in the tree. Hence we have
	 * to update the b_ops pointer as well to match the buffer type change
	 * that could occur. For dir3 blocks we also need to update the block
	 * number in the buffer header.
	 */
	memcpy(root_blk->bp->b_addr, bp->b_addr, state->blocksize);
	root_blk->bp->b_ops = bp->b_ops;
	xfs_trans_buf_copy_type(root_blk->bp, bp);
	if (oldroothdr.magic == XFS_DA3_NODE_MAGIC) {
		struct xfs_da3_blkinfo *da3 = root_blk->bp->b_addr;
		da3->blkno = cpu_to_be64(root_blk->bp->b_bn);
	}
	xfs_trans_log_buf(args->trans, root_blk->bp, 0, state->blocksize - 1);
	error = xfs_da_shrink_inode(args, child, bp);
	return(error);
}

Project: linux
File: xfs_da_btree.c

xfs_da3_root_split(
	struct xfs_da_state	*state,
	struct xfs_da_state_blk	*blk1,
	struct xfs_da_state_blk	*blk2)
{
	struct xfs_da_intnode	*node;
	struct xfs_da_intnode	*oldroot;
	struct xfs_da_node_entry *btree;
	struct xfs_da3_icnode_hdr nodehdr;
	struct xfs_da_args	*args;
	struct xfs_buf		*bp;
	struct xfs_inode	*dp;
	struct xfs_trans	*tp;
	struct xfs_mount	*mp;
	struct xfs_dir2_leaf	*leaf;
	xfs_dablk_t		blkno;
	int			level;
	int			error;
	int			size;

	trace_xfs_da_root_split(state->args);

	/*
	 * Copy the existing (incorrect) block from the root node position
	 * to a free space somewhere.
	 */
	args = state->args;
	error = xfs_da_grow_inode(args, &blkno);
	if (error)
		return error;

	dp = args->dp;
	tp = args->trans;
	mp = state->mp;
	error = xfs_da_get_buf(tp, dp, blkno, -1, &bp, args->whichfork);
	if (error)
		return error;
	node = bp->b_addr;
	oldroot = blk1->bp->b_addr;
	if (oldroot->hdr.info.magic == cpu_to_be16(XFS_DA_NODE_MAGIC) ||
	    oldroot->hdr.info.magic == cpu_to_be16(XFS_DA3_NODE_MAGIC)) {
		struct xfs_da3_icnode_hdr nodehdr;

		dp->d_ops->node_hdr_from_disk(&nodehdr, oldroot);
		btree = dp->d_ops->node_tree_p(oldroot);
		size = (int)((char *)&btree[nodehdr.count] - (char *)oldroot);
		level = nodehdr.level;

		/*
		 * we are about to copy oldroot to bp, so set up the type
		 * of bp while we know exactly what it will be.
		 */
		xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DA_NODE_BUF);
	} else {
		struct xfs_dir3_icleaf_hdr leafhdr;
		struct xfs_dir2_leaf_entry *ents;

		leaf = (xfs_dir2_leaf_t *)oldroot;
		dp->d_ops->leaf_hdr_from_disk(&leafhdr, leaf);
		ents = dp->d_ops->leaf_ents_p(leaf);

		ASSERT(leafhdr.magic == XFS_DIR2_LEAFN_MAGIC ||
		       leafhdr.magic == XFS_DIR3_LEAFN_MAGIC);
		size = (int)((char *)&ents[leafhdr.count] - (char *)leaf);
		level = 0;

		/*
		 * we are about to copy oldroot to bp, so set up the type
		 * of bp while we know exactly what it will be.
		 */
		xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAFN_BUF);
	}

	/*
	 * we can copy most of the information in the node from one block to
	 * another, but for CRC enabled headers we have to make sure that the
	 * block specific identifiers are kept intact. We update the buffer
	 * directly for this.
	 */
	memcpy(node, oldroot, size);
	if (oldroot->hdr.info.magic == cpu_to_be16(XFS_DA3_NODE_MAGIC) ||
	    oldroot->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC)) {
		struct xfs_da3_intnode *node3 = (struct xfs_da3_intnode *)node;

		node3->hdr.info.blkno = cpu_to_be64(bp->b_bn);
	}
	xfs_trans_log_buf(tp, bp, 0, size - 1);

	bp->b_ops = blk1->bp->b_ops;
	xfs_trans_buf_copy_type(bp, blk1->bp);
	blk1->bp = bp;
	blk1->blkno = blkno;

	/*
	 * Set up the new root node.
	 */
	error = xfs_da3_node_create(args,
		(args->whichfork == XFS_DATA_FORK) ? mp->m_dirleafblk : 0,
		level + 1, &bp, args->whichfork);
	if (error)
		return error;

	node = bp->b_addr;
	dp->d_ops->node_hdr_from_disk(&nodehdr, node);
	btree = dp->d_ops->node_tree_p(node);
	btree[0].hashval = cpu_to_be32(blk1->hashval);
	btree[0].before = cpu_to_be32(blk1->blkno);
	btree[1].hashval = cpu_to_be32(blk2->hashval);
	btree[1].before = cpu_to_be32(blk2->blkno);
	nodehdr.count = 2;
	dp->d_ops->node_hdr_to_disk(node, &nodehdr);

#ifdef DEBUG
	if (oldroot->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
	    oldroot->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC)) {
		ASSERT(blk1->blkno >= mp->m_dirleafblk &&
		       blk1->blkno < mp->m_dirfreeblk);
		ASSERT(blk2->blkno >= mp->m_dirleafblk &&
		       blk2->blkno < mp->m_dirfreeblk);
	}
#endif

	/* Header is already logged by xfs_da_node_create */
	xfs_trans_log_buf(tp, bp,
		XFS_DA_LOGRANGE(node, btree, sizeof(xfs_da_node_entry_t) * 2));

	return 0;
}

Project: linux
File: xfs_da_btree.c

xfs_da3_split(
	struct xfs_da_state	*state)
{
	struct xfs_da_state_blk	*oldblk;
	struct xfs_da_state_blk	*newblk;
	struct xfs_da_state_blk	*addblk;
	struct xfs_da_intnode	*node;
	struct xfs_buf		*bp;
	int			max;
	int			action = 0;
	int			error;
	int			i;

	trace_xfs_da_split(state->args);

	/*
	 * Walk back up the tree splitting/inserting/adjusting as necessary.
	 * If we need to insert and there isn't room, split the node, then
	 * decide which fragment to insert the new block from below into.
	 * Note that we may split the root this way, but we need more fixup.
	 */
	max = state->path.active - 1;
	ASSERT((max >= 0) && (max < XFS_DA_NODE_MAXDEPTH));
	ASSERT(state->path.blk[max].magic == XFS_ATTR_LEAF_MAGIC ||
	       state->path.blk[max].magic == XFS_DIR2_LEAFN_MAGIC);

	addblk = &state->path.blk[max];		/* initial dummy value */
	for (i = max; (i >= 0) && addblk; state->path.active--, i--) {
		oldblk = &state->path.blk[i];
		newblk = &state->altpath.blk[i];

		/*
		 * If a leaf node then
		 *     Allocate a new leaf node, then rebalance across them.
		 * else if an intermediate node then
		 *     We split on the last layer, must we split the node?
		 */
		switch (oldblk->magic) {
		case XFS_ATTR_LEAF_MAGIC:
			error = xfs_attr3_leaf_split(state, oldblk, newblk);
			if ((error != 0) && (error != ENOSPC)) {
				return(error);	/* GROT: attr is inconsistent */
			}
			if (!error) {
				addblk = newblk;
				break;
			}
			/*
			 * Entry wouldn't fit, split the leaf again.
			 */
			state->extravalid = 1;
			if (state->inleaf) {
				state->extraafter = 0;	/* before newblk */
				trace_xfs_attr_leaf_split_before(state->args);
				error = xfs_attr3_leaf_split(state, oldblk,
							    &state->extrablk);
			} else {
				state->extraafter = 1;	/* after newblk */
				trace_xfs_attr_leaf_split_after(state->args);
				error = xfs_attr3_leaf_split(state, newblk,
							    &state->extrablk);
			}
			if (error)
				return(error);	/* GROT: attr inconsistent */
			addblk = newblk;
			break;
		case XFS_DIR2_LEAFN_MAGIC:
			error = xfs_dir2_leafn_split(state, oldblk, newblk);
			if (error)
				return error;
			addblk = newblk;
			break;
		case XFS_DA_NODE_MAGIC:
			error = xfs_da3_node_split(state, oldblk, newblk, addblk,
							 max - i, &action);
			addblk->bp = NULL;
			if (error)
				return(error);	/* GROT: dir is inconsistent */
			/*
			 * Record the newly split block for the next time thru?
			 */
			if (action)
				addblk = newblk;
			else
				addblk = NULL;
			break;
		}

		/*
		 * Update the btree to show the new hashval for this child.
		 */
		xfs_da3_fixhashpath(state, &state->path);
	}
	if (!addblk)
		return(0);

	/*
	 * Split the root node.
	 */
	ASSERT(state->path.active == 0);
	oldblk = &state->path.blk[0];
	error = xfs_da3_root_split(state, oldblk, addblk);
	if (error) {
		addblk->bp = NULL;
		return(error);	/* GROT: dir is inconsistent */
	}

	/*
	 * Update pointers to the node which used to be block 0 and
	 * just got bumped because of the addition of a new root node.
	 * There might be three blocks involved if a double split occurred,
	 * and the original block 0 could be at any position in the list.
	 *
	 * Note: the magic numbers and sibling pointers are in the same
	 * physical place for both v2 and v3 headers (by design). Hence it
	 * doesn't matter which version of the xfs_da_intnode structure we use
	 * here as the result will be the same using either structure.
	 */
	node = oldblk->bp->b_addr;
	if (node->hdr.info.forw) {
		if (be32_to_cpu(node->hdr.info.forw) == addblk->blkno) {
			bp = addblk->bp;
		} else {
			ASSERT(state->extravalid);
			bp = state->extrablk.bp;
		}
		node = bp->b_addr;
		node->hdr.info.back = cpu_to_be32(oldblk->blkno);
		xfs_trans_log_buf(state->args->trans, bp,
		    XFS_DA_LOGRANGE(node, &node->hdr.info,
		    sizeof(node->hdr.info)));
	}
	node = oldblk->bp->b_addr;
	if (node->hdr.info.back) {
		if (be32_to_cpu(node->hdr.info.back) == addblk->blkno) {
			bp = addblk->bp;
		} else {
			ASSERT(state->extravalid);
			bp = state->extrablk.bp;
		}
		node = bp->b_addr;
		node->hdr.info.forw = cpu_to_be32(oldblk->blkno);
		xfs_trans_log_buf(state->args->trans, bp,
		    XFS_DA_LOGRANGE(node, &node->hdr.info,
		    sizeof(node->hdr.info)));
	}
	addblk->bp = NULL;
	return(0);
}

Project: linux
File: xfs_da_btree.c

xfs_da3_swap_lastblock(
	struct xfs_da_args	*args,
	xfs_dablk_t		*dead_blknop,
	struct xfs_buf		**dead_bufp)
{
	struct xfs_da_blkinfo	*dead_info;
	struct xfs_da_blkinfo	*sib_info;
	struct xfs_da_intnode	*par_node;
	struct xfs_da_intnode	*dead_node;
	struct xfs_dir2_leaf	*dead_leaf2;
	struct xfs_da_node_entry *btree;
	struct xfs_da3_icnode_hdr par_hdr;
	struct xfs_inode	*dp;
	struct xfs_trans	*tp;
	struct xfs_mount	*mp;
	struct xfs_buf		*dead_buf;
	struct xfs_buf		*last_buf;
	struct xfs_buf		*sib_buf;
	struct xfs_buf		*par_buf;
	xfs_dahash_t		dead_hash;
	xfs_fileoff_t		lastoff;
	xfs_dablk_t		dead_blkno;
	xfs_dablk_t		last_blkno;
	xfs_dablk_t		sib_blkno;
	xfs_dablk_t		par_blkno;
	int			error;
	int			w;
	int			entno;
	int			level;
	int			dead_level;

	trace_xfs_da_swap_lastblock(args);

	dead_buf = *dead_bufp;
	dead_blkno = *dead_blknop;
	tp = args->trans;
	dp = args->dp;
	w = args->whichfork;
	ASSERT(w == XFS_DATA_FORK);
	mp = dp->i_mount;
	lastoff = mp->m_dirfreeblk;
	error = xfs_bmap_last_before(tp, dp, &lastoff, w);
	if (error)
		return error;
	if (unlikely(lastoff == 0)) {
		XFS_ERROR_REPORT("xfs_da_swap_lastblock(1)", XFS_ERRLEVEL_LOW,
				 mp);
		return XFS_ERROR(EFSCORRUPTED);
	}
	/*
	 * Read the last block in the btree space.
	 */
	last_blkno = (xfs_dablk_t)lastoff - mp->m_dirblkfsbs;
	error = xfs_da3_node_read(tp, dp, last_blkno, -1, &last_buf, w);
	if (error)
		return error;
	/*
	 * Copy the last block into the dead buffer and log it.
	 */
	memcpy(dead_buf->b_addr, last_buf->b_addr, mp->m_dirblksize);
	xfs_trans_log_buf(tp, dead_buf, 0, mp->m_dirblksize - 1);
	dead_info = dead_buf->b_addr;
	/*
	 * Get values from the moved block.
	 */
	if (dead_info->magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
	    dead_info->magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC)) {
		struct xfs_dir3_icleaf_hdr leafhdr;
		struct xfs_dir2_leaf_entry *ents;

		dead_leaf2 = (xfs_dir2_leaf_t *)dead_info;
		dp->d_ops->leaf_hdr_from_disk(&leafhdr, dead_leaf2);
		ents = dp->d_ops->leaf_ents_p(dead_leaf2);
		dead_level = 0;
		dead_hash = be32_to_cpu(ents[leafhdr.count - 1].hashval);
	} else {
		struct xfs_da3_icnode_hdr deadhdr;

		dead_node = (xfs_da_intnode_t *)dead_info;
		dp->d_ops->node_hdr_from_disk(&deadhdr, dead_node);
		btree = dp->d_ops->node_tree_p(dead_node);
		dead_level = deadhdr.level;
		dead_hash = be32_to_cpu(btree[deadhdr.count - 1].hashval);
	}
	sib_buf = par_buf = NULL;
	/*
	 * If the moved block has a left sibling, fix up the pointers.
	 */
	if ((sib_blkno = be32_to_cpu(dead_info->back))) {
		error = xfs_da3_node_read(tp, dp, sib_blkno, -1, &sib_buf, w);
		if (error)
			goto done;
		sib_info = sib_buf->b_addr;
		if (unlikely(
		    be32_to_cpu(sib_info->forw) != last_blkno ||
		    sib_info->magic != dead_info->magic)) {
			XFS_ERROR_REPORT("xfs_da_swap_lastblock(2)",
					 XFS_ERRLEVEL_LOW, mp);
			error = XFS_ERROR(EFSCORRUPTED);
			goto done;
		}
		sib_info->forw = cpu_to_be32(dead_blkno);
		xfs_trans_log_buf(tp, sib_buf,
			XFS_DA_LOGRANGE(sib_info, &sib_info->forw,
					sizeof(sib_info->forw)));
		sib_buf = NULL;
	}
	/*
	 * If the moved block has a right sibling, fix up the pointers.
	 */
	if ((sib_blkno = be32_to_cpu(dead_info->forw))) {
		error = xfs_da3_node_read(tp, dp, sib_blkno, -1, &sib_buf, w);
		if (error)
			goto done;
		sib_info = sib_buf->b_addr;
		if (unlikely(
		       be32_to_cpu(sib_info->back) != last_blkno ||
		       sib_info->magic != dead_info->magic)) {
			XFS_ERROR_REPORT("xfs_da_swap_lastblock(3)",
					 XFS_ERRLEVEL_LOW, mp);
			error = XFS_ERROR(EFSCORRUPTED);
			goto done;
		}
		sib_info->back = cpu_to_be32(dead_blkno);
		xfs_trans_log_buf(tp, sib_buf,
			XFS_DA_LOGRANGE(sib_info, &sib_info->back,
					sizeof(sib_info->back)));
		sib_buf = NULL;
	}
	par_blkno = mp->m_dirleafblk;
	level = -1;
	/*
	 * Walk down the tree looking for the parent of the moved block.
	 */
	for (;;) {
		error = xfs_da3_node_read(tp, dp, par_blkno, -1, &par_buf, w);
		if (error)
			goto done;
		par_node = par_buf->b_addr;
		dp->d_ops->node_hdr_from_disk(&par_hdr, par_node);
		if (level >= 0 && level != par_hdr.level + 1) {
			XFS_ERROR_REPORT("xfs_da_swap_lastblock(4)",
					 XFS_ERRLEVEL_LOW, mp);
			error = XFS_ERROR(EFSCORRUPTED);
			goto done;
		}
		level = par_hdr.level;
		btree = dp->d_ops->node_tree_p(par_node);
		for (entno = 0;
		     entno < par_hdr.count &&
		     be32_to_cpu(btree[entno].hashval) < dead_hash;
		     entno++)
			continue;
		if (entno == par_hdr.count) {
			XFS_ERROR_REPORT("xfs_da_swap_lastblock(5)",
					 XFS_ERRLEVEL_LOW, mp);
			error = XFS_ERROR(EFSCORRUPTED);
			goto done;
		}
		par_blkno = be32_to_cpu(btree[entno].before);
		if (level == dead_level + 1)
			break;
		xfs_trans_brelse(tp, par_buf);
		par_buf = NULL;
	}
	/*
	 * We're in the right parent block.
	 * Look for the right entry.
	 */
	for (;;) {
		for (;
		     entno < par_hdr.count &&
		     be32_to_cpu(btree[entno].before) != last_blkno;
		     entno++)
			continue;
		if (entno < par_hdr.count)
			break;
		par_blkno = par_hdr.forw;
		xfs_trans_brelse(tp, par_buf);
		par_buf = NULL;
		if (unlikely(par_blkno == 0)) {
			XFS_ERROR_REPORT("xfs_da_swap_lastblock(6)",
					 XFS_ERRLEVEL_LOW, mp);
			error = XFS_ERROR(EFSCORRUPTED);
			goto done;
		}
		error = xfs_da3_node_read(tp, dp, par_blkno, -1, &par_buf, w);
		if (error)
			goto done;
		par_node = par_buf->b_addr;
		dp->d_ops->node_hdr_from_disk(&par_hdr, par_node);
		if (par_hdr.level != level) {
			XFS_ERROR_REPORT("xfs_da_swap_lastblock(7)",
					 XFS_ERRLEVEL_LOW, mp);
			error = XFS_ERROR(EFSCORRUPTED);
			goto done;
		}
		btree = dp->d_ops->node_tree_p(par_node);
		entno = 0;
	}
	/*
	 * Update the parent entry pointing to the moved block.
	 */
	btree[entno].before = cpu_to_be32(dead_blkno);
	xfs_trans_log_buf(tp, par_buf,
		XFS_DA_LOGRANGE(par_node, &btree[entno].before,
				sizeof(btree[entno].before)));
	*dead_blknop = last_blkno;
	*dead_bufp = last_buf;
	return 0;
done:
	if (par_buf)
		xfs_trans_brelse(tp, par_buf);
	if (sib_buf)
		xfs_trans_brelse(tp, sib_buf);
	xfs_trans_brelse(tp, last_buf);
	return error;
}

Project: linux
File: xfs_da_btree.c

xfs_da_blkinfo_onlychild_validate(struct xfs_da_blkinfo *blkinfo, __u16 level)
{
	__be16	magic = blkinfo->magic;

	if (level == 1) {
		ASSERT(magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
		       magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC) ||
		       magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC) ||
		       magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC));
	} else {
		ASSERT(magic == cpu_to_be16(XFS_DA_NODE_MAGIC) ||
		       magic == cpu_to_be16(XFS_DA3_NODE_MAGIC));
	}
	ASSERT(!blkinfo->forw);
	ASSERT(!blkinfo->back);
}

Project: linux
File: xfs_da_btree.c

xfs_da_compname(
	struct xfs_da_args *args,
	const unsigned char *name,
	int		len)
{
	return (args->namelen == len && memcmp(args->name, name, len) == 0) ?
					XFS_CMP_EXACT : XFS_CMP_DIFFERENT;
}

Project: linux
File: xfs_da_btree.c

xfs_da_get_buf(
	struct xfs_trans	*trans,
	struct xfs_inode	*dp,
	xfs_dablk_t		bno,
	xfs_daddr_t		mappedbno,
	struct xfs_buf		**bpp,
	int			whichfork)
{
	struct xfs_buf		*bp;
	struct xfs_buf_map	map;
	struct xfs_buf_map	*mapp;
	int			nmap;
	int			error;

	*bpp = NULL;
	mapp = &map;
	nmap = 1;
	error = xfs_dabuf_map(trans, dp, bno, mappedbno, whichfork,
				&mapp, &nmap);
	if (error) {
		/* mapping a hole is not an error, but we don't continue */
		if (error == -1)
			error = 0;
		goto out_free;
	}

	bp = xfs_trans_get_buf_map(trans, dp->i_mount->m_ddev_targp,
				    mapp, nmap, 0);
	error = bp ? bp->b_error : XFS_ERROR(EIO);
	if (error) {
		xfs_trans_brelse(trans, bp);
		goto out_free;
	}

	*bpp = bp;

out_free:
	if (mapp != &map)
		kmem_free(mapp);

	return error;
}

Project: linux
File: xfs_da_btree.c

xfs_da_grow_inode(
	struct xfs_da_args	*args,
	xfs_dablk_t		*new_blkno)
{
	xfs_fileoff_t		bno;
	int			count;
	int			error;

	trace_xfs_da_grow_inode(args);

	if (args->whichfork == XFS_DATA_FORK) {
		bno = args->dp->i_mount->m_dirleafblk;
		count = args->dp->i_mount->m_dirblkfsbs;
	} else {
		bno = 0;
		count = 1;
	}

	error = xfs_da_grow_inode_int(args, &bno, count);
	if (!error)
		*new_blkno = (xfs_dablk_t)bno;
	return error;
}

Project: linux
File: xfs_da_btree.c

xfs_da_grow_inode_int(
	struct xfs_da_args	*args,
	xfs_fileoff_t		*bno,
	int			count)
{
	struct xfs_trans	*tp = args->trans;
	struct xfs_inode	*dp = args->dp;
	int			w = args->whichfork;
	xfs_drfsbno_t		nblks = dp->i_d.di_nblocks;
	struct xfs_bmbt_irec	map, *mapp;
	int			nmap, error, got, i, mapi;

	/*
	 * Find a spot in the file space to put the new block.
	 */
	error = xfs_bmap_first_unused(tp, dp, count, bno, w);
	if (error)
		return error;

	/*
	 * Try mapping it in one filesystem block.
	 */
	nmap = 1;
	ASSERT(args->firstblock != NULL);
	error = xfs_bmapi_write(tp, dp, *bno, count,
			xfs_bmapi_aflag(w)|XFS_BMAPI_METADATA|XFS_BMAPI_CONTIG,
			args->firstblock, args->total, &map, &nmap,
			args->flist);
	if (error)
		return error;

	ASSERT(nmap <= 1);
	if (nmap == 1) {
		mapp = &map;
		mapi = 1;
	} else if (nmap == 0 && count > 1) {
		xfs_fileoff_t		b;
		int			c;

		/*
		 * If we didn't get it and the block might work if fragmented,
		 * try without the CONTIG flag.  Loop until we get it all.
		 */
		mapp = kmem_alloc(sizeof(*mapp) * count, KM_SLEEP);
		for (b = *bno, mapi = 0; b < *bno + count; ) {
			nmap = MIN(XFS_BMAP_MAX_NMAP, count);
			c = (int)(*bno + count - b);
			error = xfs_bmapi_write(tp, dp, b, c,
					xfs_bmapi_aflag(w)|XFS_BMAPI_METADATA,
					args->firstblock, args->total,
					&mapp[mapi], &nmap, args->flist);
			if (error)
				goto out_free_map;
			if (nmap < 1)
				break;
			mapi += nmap;
			b = mapp[mapi - 1].br_startoff +
			    mapp[mapi - 1].br_blockcount;
		}
	} else {
		mapi = 0;
		mapp = NULL;
	}

	/*
	 * Count the blocks we got, make sure it matches the total.
	 */
	for (i = 0, got = 0; i < mapi; i++)
		got += mapp[i].br_blockcount;
	if (got != count || mapp[0].br_startoff != *bno ||
	    mapp[mapi - 1].br_startoff + mapp[mapi - 1].br_blockcount !=
	    *bno + count) {
		error = XFS_ERROR(ENOSPC);
		goto out_free_map;
	}

	/* account for newly allocated blocks in reserved blocks total */
	args->total -= dp->i_d.di_nblocks - nblks;

out_free_map:
	if (mapp != &map)
		kmem_free(mapp);
	return error;
}

Project: linux
File: xfs_da_btree.c

xfs_da_map_covers_blocks(
	int		nmap,
	xfs_bmbt_irec_t	*mapp,
	xfs_dablk_t	bno,
	int		count)
{
	int		i;
	xfs_fileoff_t	off;

	for (i = 0, off = bno; i < nmap; i++) {
		if (mapp[i].br_startblock == HOLESTARTBLOCK ||
		    mapp[i].br_startblock == DELAYSTARTBLOCK) {
			return 0;
		}
		if (off != mapp[i].br_startoff) {
			return 0;
		}
		off += mapp[i].br_blockcount;
	}
	return off == bno + count;
}

Project: linux
File: xfs_da_btree.c

xfs_da_read_buf(
	struct xfs_trans	*trans,
	struct xfs_inode	*dp,
	xfs_dablk_t		bno,
	xfs_daddr_t		mappedbno,
	struct xfs_buf		**bpp,
	int			whichfork,
	const struct xfs_buf_ops *ops)
{
	struct xfs_buf		*bp;
	struct xfs_buf_map	map;
	struct xfs_buf_map	*mapp;
	int			nmap;
	int			error;

	*bpp = NULL;
	mapp = &map;
	nmap = 1;
	error = xfs_dabuf_map(trans, dp, bno, mappedbno, whichfork,
				&mapp, &nmap);
	if (error) {
		/* mapping a hole is not an error, but we don't continue */
		if (error == -1)
			error = 0;
		goto out_free;
	}

	error = xfs_trans_read_buf_map(dp->i_mount, trans,
					dp->i_mount->m_ddev_targp,
					mapp, nmap, 0, &bp, ops);
	if (error)
		goto out_free;

	if (whichfork == XFS_ATTR_FORK)
		xfs_buf_set_ref(bp, XFS_ATTR_BTREE_REF);
	else
		xfs_buf_set_ref(bp, XFS_DIR_BTREE_REF);

	/*
	 * This verification code will be moved to a CRC verification callback
	 * function so just leave it here unchanged until then.
	 */
	{
		xfs_dir2_data_hdr_t	*hdr = bp->b_addr;
		xfs_dir2_free_t		*free = bp->b_addr;
		xfs_da_blkinfo_t	*info = bp->b_addr;
		uint			magic, magic1;
		struct xfs_mount	*mp = dp->i_mount;

		magic = be16_to_cpu(info->magic);
		magic1 = be32_to_cpu(hdr->magic);
		if (unlikely(
		    XFS_TEST_ERROR((magic != XFS_DA_NODE_MAGIC) &&
				   (magic != XFS_DA3_NODE_MAGIC) &&
				   (magic != XFS_ATTR_LEAF_MAGIC) &&
				   (magic != XFS_ATTR3_LEAF_MAGIC) &&
				   (magic != XFS_DIR2_LEAF1_MAGIC) &&
				   (magic != XFS_DIR3_LEAF1_MAGIC) &&
				   (magic != XFS_DIR2_LEAFN_MAGIC) &&
				   (magic != XFS_DIR3_LEAFN_MAGIC) &&
				   (magic1 != XFS_DIR2_BLOCK_MAGIC) &&
				   (magic1 != XFS_DIR3_BLOCK_MAGIC) &&
				   (magic1 != XFS_DIR2_DATA_MAGIC) &&
				   (magic1 != XFS_DIR3_DATA_MAGIC) &&
				   (free->hdr.magic !=
					cpu_to_be32(XFS_DIR2_FREE_MAGIC)) &&
				   (free->hdr.magic !=
					cpu_to_be32(XFS_DIR3_FREE_MAGIC)),
				mp, XFS_ERRTAG_DA_READ_BUF,
				XFS_RANDOM_DA_READ_BUF))) {
			trace_xfs_da_btree_corrupt(bp, _RET_IP_);
			XFS_CORRUPTION_ERROR("xfs_da_do_buf(2)",
					     XFS_ERRLEVEL_LOW, mp, info);
			error = XFS_ERROR(EFSCORRUPTED);
			xfs_trans_brelse(trans, bp);
			goto out_free;
		}
	}
	*bpp = bp;
out_free:
	if (mapp != &map)
		kmem_free(mapp);

	return error;
}

Project: linux
File: xfs_da_btree.c

xfs_da_reada_buf(
	struct xfs_trans	*trans,
	struct xfs_inode	*dp,
	xfs_dablk_t		bno,
	xfs_daddr_t		mappedbno,
	int			whichfork,
	const struct xfs_buf_ops *ops)
{
	struct xfs_buf_map	map;
	struct xfs_buf_map	*mapp;
	int			nmap;
	int			error;

	mapp = &map;
	nmap = 1;
	error = xfs_dabuf_map(trans, dp, bno, mappedbno, whichfork,
				&mapp, &nmap);
	if (error) {
		/* mapping a hole is not an error, but we don't continue */
		if (error == -1)
			error = 0;
		goto out_free;
	}

	mappedbno = mapp[0].bm_bn;
	xfs_buf_readahead_map(dp->i_mount->m_ddev_targp, mapp, nmap, ops);

out_free:
	if (mapp != &map)
		kmem_free(mapp);

	if (error)
		return -1;
	return mappedbno;
}

Project: linux
File: xfs_da_btree.c

xfs_da_shrink_inode(
	xfs_da_args_t	*args,
	xfs_dablk_t	dead_blkno,
	struct xfs_buf	*dead_buf)
{
	xfs_inode_t *dp;
	int done, error, w, count;
	xfs_trans_t *tp;
	xfs_mount_t *mp;

	trace_xfs_da_shrink_inode(args);

	dp = args->dp;
	w = args->whichfork;
	tp = args->trans;
	mp = dp->i_mount;
	if (w == XFS_DATA_FORK)
		count = mp->m_dirblkfsbs;
	else
		count = 1;
	for (;;) {
		/*
		 * Remove extents.  If we get ENOSPC for a dir we have to move
		 * the last block to the place we want to kill.
		 */
		error = xfs_bunmapi(tp, dp, dead_blkno, count,
				    xfs_bmapi_aflag(w)|XFS_BMAPI_METADATA,
				    0, args->firstblock, args->flist, &done);
		if (error == ENOSPC) {
			if (w != XFS_DATA_FORK)
				break;
			error = xfs_da3_swap_lastblock(args, &dead_blkno,
						      &dead_buf);
			if (error)
				break;
		} else {
			break;
		}
	}
	xfs_trans_binval(tp, dead_buf);
	return error;
}

Project: linux
File: xfs_da_btree.c

xfs_da_state_alloc(void)
{
	return kmem_zone_zalloc(xfs_da_state_zone, KM_NOFS);
}

Project: linux
File: xfs_da_btree.c

xfs_da_state_free(xfs_da_state_t *state)
{
	xfs_da_state_kill_altpath(state);
#ifdef DEBUG
	memset((char *)state, 0, sizeof(*state));
#endif /* DEBUG */
	kmem_zone_free(xfs_da_state_zone, state);
}

Project: linux
File: xfs_da_btree.c

xfs_da_state_kill_altpath(xfs_da_state_t *state)
{
	int	i;

	for (i = 0; i < state->altpath.active; i++)
		state->altpath.blk[i].bp = NULL;
	state->altpath.active = 0;
}

Project: linux
File: xfs_da_btree.c

xfs_dabuf_map(
	struct xfs_trans	*trans,
	struct xfs_inode	*dp,
	xfs_dablk_t		bno,
	xfs_daddr_t		mappedbno,
	int			whichfork,
	struct xfs_buf_map	**map,
	int			*nmaps)
{
	struct xfs_mount	*mp = dp->i_mount;
	int			nfsb;
	int			error = 0;
	struct xfs_bmbt_irec	irec;
	struct xfs_bmbt_irec	*irecs = &irec;
	int			nirecs;

	ASSERT(map && *map);
	ASSERT(*nmaps == 1);

	nfsb = (whichfork == XFS_DATA_FORK) ? mp->m_dirblkfsbs : 1;

	/*
	 * Caller doesn't have a mapping.  -2 means don't complain
	 * if we land in a hole.
	 */
	if (mappedbno == -1 || mappedbno == -2) {
		/*
		 * Optimize the one-block case.
		 */
		if (nfsb != 1)
			irecs = kmem_zalloc(sizeof(irec) * nfsb,
					    KM_SLEEP | KM_NOFS);

		nirecs = nfsb;
		error = xfs_bmapi_read(dp, (xfs_fileoff_t)bno, nfsb, irecs,
				       &nirecs, xfs_bmapi_aflag(whichfork));
		if (error)
			goto out;
	} else {
		irecs->br_startblock = XFS_DADDR_TO_FSB(mp, mappedbno);
		irecs->br_startoff = (xfs_fileoff_t)bno;
		irecs->br_blockcount = nfsb;
		irecs->br_state = 0;
		nirecs = 1;
	}

	if (!xfs_da_map_covers_blocks(nirecs, irecs, bno, nfsb)) {
		error = mappedbno == -2 ? -1 : XFS_ERROR(EFSCORRUPTED);
		if (unlikely(error == EFSCORRUPTED)) {
			if (xfs_error_level >= XFS_ERRLEVEL_LOW) {
				int i;
				xfs_alert(mp, "%s: bno %lld dir: inode %lld",
					__func__, (long long)bno,
					(long long)dp->i_ino);
				for (i = 0; i < *nmaps; i++) {
					xfs_alert(mp,
"[%02d] br_startoff %lld br_startblock %lld br_blockcount %lld br_state %d",
						i,
						(long long)irecs[i].br_startoff,
						(long long)irecs[i].br_startblock,
						(long long)irecs[i].br_blockcount,
						irecs[i].br_state);
				}
			}
			XFS_ERROR_REPORT("xfs_da_do_buf(1)",
					 XFS_ERRLEVEL_LOW, mp);
		}
		goto out;
	}
	error = xfs_buf_map_from_irec(mp, map, nmaps, irecs, nirecs);
out:
	if (irecs != &irec)
		kmem_free(irecs);
	return error;
}

Project: linux
File: xfs_da_btree.c

xfs_default_hashname(
	struct xfs_name	*name)
{
	return xfs_da_hashname(name->name, name->len);
}