ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/fs/xfs/libxfs/xfs_da_btree.c b/marvell/linux/fs/xfs/libxfs/xfs_da_btree.c
new file mode 100644
index 0000000..12ef16c
--- /dev/null
+++ b/marvell/linux/fs/xfs/libxfs/xfs_da_btree.c
@@ -0,0 +1,2731 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2000-2005 Silicon Graphics, Inc.
+ * Copyright (c) 2013 Red Hat, Inc.
+ * All Rights Reserved.
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_shared.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_bit.h"
+#include "xfs_mount.h"
+#include "xfs_dir2.h"
+#include "xfs_dir2_priv.h"
+#include "xfs_inode.h"
+#include "xfs_trans.h"
+#include "xfs_bmap.h"
+#include "xfs_attr_leaf.h"
+#include "xfs_error.h"
+#include "xfs_trace.h"
+#include "xfs_buf_item.h"
+#include "xfs_log.h"
+
+/*
+ * xfs_da_btree.c
+ *
+ * Routines to implement directories as Btrees of hashed names.
+ */
+
+/*========================================================================
+ * Function prototypes for the kernel.
+ *========================================================================*/
+
+/*
+ * Routines used for growing the Btree.
+ */
+STATIC int xfs_da3_root_split(xfs_da_state_t *state,
+ xfs_da_state_blk_t *existing_root,
+ xfs_da_state_blk_t *new_child);
+STATIC int xfs_da3_node_split(xfs_da_state_t *state,
+ xfs_da_state_blk_t *existing_blk,
+ xfs_da_state_blk_t *split_blk,
+ xfs_da_state_blk_t *blk_to_add,
+ int treelevel,
+ int *result);
+STATIC void xfs_da3_node_rebalance(xfs_da_state_t *state,
+ xfs_da_state_blk_t *node_blk_1,
+ xfs_da_state_blk_t *node_blk_2);
+STATIC void xfs_da3_node_add(xfs_da_state_t *state,
+ xfs_da_state_blk_t *old_node_blk,
+ xfs_da_state_blk_t *new_node_blk);
+
+/*
+ * Routines used for shrinking the Btree.
+ */
+STATIC int xfs_da3_root_join(xfs_da_state_t *state,
+ xfs_da_state_blk_t *root_blk);
+STATIC int xfs_da3_node_toosmall(xfs_da_state_t *state, int *retval);
+STATIC void xfs_da3_node_remove(xfs_da_state_t *state,
+ xfs_da_state_blk_t *drop_blk);
+STATIC void xfs_da3_node_unbalance(xfs_da_state_t *state,
+ xfs_da_state_blk_t *src_node_blk,
+ xfs_da_state_blk_t *dst_node_blk);
+
+/*
+ * Utility routines.
+ */
+STATIC int xfs_da3_blk_unlink(xfs_da_state_t *state,
+ xfs_da_state_blk_t *drop_blk,
+ xfs_da_state_blk_t *save_blk);
+
+
+kmem_zone_t *xfs_da_state_zone; /* anchor for state struct zone */
+
+/*
+ * Allocate a dir-state structure.
+ * We don't put them on the stack since they're large.
+ */
+xfs_da_state_t *
+xfs_da_state_alloc(void)
+{
+ return kmem_zone_zalloc(xfs_da_state_zone, KM_NOFS);
+}
+
+/*
+ * Kill the altpath contents of a da-state structure.
+ */
+STATIC void
+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;
+}
+
+/*
+ * Free a da-state structure.
+ */
+void
+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);
+}
+
+/*
+ * Verify an xfs_da3_blkinfo structure. Note that the da3 fields are only
+ * accessible on v5 filesystems. This header format is common across da node,
+ * attr leaf and dir leaf blocks.
+ */
+xfs_failaddr_t
+xfs_da3_blkinfo_verify(
+ struct xfs_buf *bp,
+ struct xfs_da3_blkinfo *hdr3)
+{
+ struct xfs_mount *mp = bp->b_mount;
+ struct xfs_da_blkinfo *hdr = &hdr3->hdr;
+
+ if (!xfs_verify_magic16(bp, hdr->magic))
+ return __this_address;
+
+ if (xfs_sb_version_hascrc(&mp->m_sb)) {
+ if (!uuid_equal(&hdr3->uuid, &mp->m_sb.sb_meta_uuid))
+ return __this_address;
+ if (be64_to_cpu(hdr3->blkno) != bp->b_bn)
+ return __this_address;
+ if (!xfs_log_check_lsn(mp, be64_to_cpu(hdr3->lsn)))
+ return __this_address;
+ }
+
+ return NULL;
+}
+
+static xfs_failaddr_t
+xfs_da3_node_verify(
+ struct xfs_buf *bp)
+{
+ struct xfs_mount *mp = bp->b_mount;
+ struct xfs_da_intnode *hdr = bp->b_addr;
+ struct xfs_da3_icnode_hdr ichdr;
+ const struct xfs_dir_ops *ops;
+ xfs_failaddr_t fa;
+
+ ops = xfs_dir_get_ops(mp, NULL);
+
+ ops->node_hdr_from_disk(&ichdr, hdr);
+
+ fa = xfs_da3_blkinfo_verify(bp, bp->b_addr);
+ if (fa)
+ return fa;
+
+ if (ichdr.level == 0)
+ return __this_address;
+ if (ichdr.level > XFS_DA_NODE_MAXDEPTH)
+ return __this_address;
+ if (ichdr.count == 0)
+ return __this_address;
+
+ /*
+ * 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_geo->node_ents &&
+ ichdr.count > mp->m_attr_geo->node_ents)
+ return __this_address;
+
+ /* XXX: hash order check? */
+
+ return NULL;
+}
+
+static void
+xfs_da3_node_write_verify(
+ struct xfs_buf *bp)
+{
+ struct xfs_mount *mp = bp->b_mount;
+ struct xfs_buf_log_item *bip = bp->b_log_item;
+ struct xfs_da3_node_hdr *hdr3 = bp->b_addr;
+ xfs_failaddr_t fa;
+
+ fa = xfs_da3_node_verify(bp);
+ if (fa) {
+ xfs_verifier_error(bp, -EFSCORRUPTED, fa);
+ return;
+ }
+
+ if (!xfs_sb_version_hascrc(&mp->m_sb))
+ return;
+
+ if (bip)
+ hdr3->info.lsn = cpu_to_be64(bip->bli_item.li_lsn);
+
+ xfs_buf_update_cksum(bp, XFS_DA3_NODE_CRC_OFF);
+}
+
+/*
+ * leaf/node format detection on trees is sketchy, so a node read can be done on
+ * leaf level blocks when detection identifies the tree as a node format tree
+ * incorrectly. In this case, we need to swap the verifier to match the correct
+ * format of the block being read.
+ */
+static void
+xfs_da3_node_read_verify(
+ struct xfs_buf *bp)
+{
+ struct xfs_da_blkinfo *info = bp->b_addr;
+ xfs_failaddr_t fa;
+
+ switch (be16_to_cpu(info->magic)) {
+ case XFS_DA3_NODE_MAGIC:
+ if (!xfs_buf_verify_cksum(bp, XFS_DA3_NODE_CRC_OFF)) {
+ xfs_verifier_error(bp, -EFSBADCRC,
+ __this_address);
+ break;
+ }
+ /* fall through */
+ case XFS_DA_NODE_MAGIC:
+ fa = xfs_da3_node_verify(bp);
+ if (fa)
+ xfs_verifier_error(bp, -EFSCORRUPTED, fa);
+ 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:
+ xfs_verifier_error(bp, -EFSCORRUPTED, __this_address);
+ break;
+ }
+}
+
+/* Verify the structure of a da3 block. */
+static xfs_failaddr_t
+xfs_da3_node_verify_struct(
+ struct xfs_buf *bp)
+{
+ struct xfs_da_blkinfo *info = bp->b_addr;
+
+ switch (be16_to_cpu(info->magic)) {
+ case XFS_DA3_NODE_MAGIC:
+ case XFS_DA_NODE_MAGIC:
+ return xfs_da3_node_verify(bp);
+ case XFS_ATTR_LEAF_MAGIC:
+ case XFS_ATTR3_LEAF_MAGIC:
+ bp->b_ops = &xfs_attr3_leaf_buf_ops;
+ return bp->b_ops->verify_struct(bp);
+ case XFS_DIR2_LEAFN_MAGIC:
+ case XFS_DIR3_LEAFN_MAGIC:
+ bp->b_ops = &xfs_dir3_leafn_buf_ops;
+ return bp->b_ops->verify_struct(bp);
+ default:
+ return __this_address;
+ }
+}
+
+const struct xfs_buf_ops xfs_da3_node_buf_ops = {
+ .name = "xfs_da3_node",
+ .magic16 = { cpu_to_be16(XFS_DA_NODE_MAGIC),
+ cpu_to_be16(XFS_DA3_NODE_MAGIC) },
+ .verify_read = xfs_da3_node_read_verify,
+ .verify_write = xfs_da3_node_write_verify,
+ .verify_struct = xfs_da3_node_verify_struct,
+};
+
+int
+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 && *bpp) {
+ 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:
+ XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW,
+ tp->t_mountp, info, sizeof(*info));
+ xfs_trans_brelse(tp, *bpp);
+ *bpp = NULL;
+ return -EFSCORRUPTED;
+ }
+ xfs_trans_buf_set_type(tp, *bpp, type);
+ }
+ return err;
+}
+
+/*========================================================================
+ * Routines used for growing the Btree.
+ *========================================================================*/
+
+/*
+ * Create the initial contents of an intermediate node.
+ */
+int
+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;
+
+ memset(hdr3, 0, sizeof(struct xfs_da3_node_hdr));
+ 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_meta_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;
+}
+
+/*
+ * Split a leaf node, rebalance, then possibly split
+ * intermediate nodes, rebalance, etc.
+ */
+int /* error */
+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;
+ 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. The new
+ * extrablk will be consumed by xfs_da3_node_split if
+ * the node is split.
+ */
+ 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;
+
+ /*
+ * xfs_da3_node_split() should have consumed any extra blocks we added
+ * during a double leaf split in the attr fork. This is guaranteed as
+ * we can't be here if the attr fork only has a single leaf block.
+ */
+ ASSERT(state->extravalid == 0 ||
+ state->path.blk[max].magic == XFS_DIR2_LEAFN_MAGIC);
+
+ /*
+ * Split the root node.
+ */
+ ASSERT(state->path.active == 0);
+ oldblk = &state->path.blk[0];
+ error = xfs_da3_root_split(state, oldblk, addblk);
+ if (error)
+ goto out;
+
+ /*
+ * Update pointers to the node which used to be block 0 and just got
+ * bumped because of the addition of a new root node. Note that the
+ * original block 0 could be at any position in the list of blocks in
+ * the tree.
+ *
+ * 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) {
+ xfs_buf_mark_corrupt(oldblk->bp);
+ error = -EFSCORRUPTED;
+ goto out;
+ }
+ node = addblk->bp->b_addr;
+ node->hdr.info.back = cpu_to_be32(oldblk->blkno);
+ xfs_trans_log_buf(state->args->trans, addblk->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) {
+ xfs_buf_mark_corrupt(oldblk->bp);
+ error = -EFSCORRUPTED;
+ goto out;
+ }
+ node = addblk->bp->b_addr;
+ node->hdr.info.forw = cpu_to_be32(oldblk->blkno);
+ xfs_trans_log_buf(state->args->trans, addblk->bp,
+ XFS_DA_LOGRANGE(node, &node->hdr.info,
+ sizeof(node->hdr.info)));
+ }
+out:
+ addblk->bp = NULL;
+ return error;
+}
+
+/*
+ * Split the root. We have to create a new root and point to the two
+ * parts (the split old root) that we just created. Copy block zero to
+ * the EOF, extending the inode in process.
+ */
+STATIC int /* error */
+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_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;
+ 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 icnodehdr;
+
+ dp->d_ops->node_hdr_from_disk(&icnodehdr, oldroot);
+ btree = dp->d_ops->node_tree_p(oldroot);
+ size = (int)((char *)&btree[icnodehdr.count] - (char *)oldroot);
+ level = icnodehdr.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) ? args->geo->leafblk : 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 >= args->geo->leafblk &&
+ blk1->blkno < args->geo->freeblk);
+ ASSERT(blk2->blkno >= args->geo->leafblk &&
+ blk2->blkno < args->geo->freeblk);
+ }
+#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;
+}
+
+/*
+ * Split the node, rebalance, then add the new entry.
+ */
+STATIC int /* error */
+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->args->geo->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;
+}
+
+/*
+ * Balance the btree elements between two intermediate nodes,
+ * usually one full and one empty.
+ *
+ * NOTE: if blk2 is empty, then it will get the upper half of blk1.
+ */
+STATIC void
+xfs_da3_node_rebalance(
+ struct xfs_da_state *state,
+ struct xfs_da_state_blk *blk1,
+ struct xfs_da_state_blk *blk2)
+{
+ struct xfs_da_intnode *node1;
+ struct xfs_da_intnode *node2;
+ struct xfs_da_intnode *tmpnode;
+ struct xfs_da_node_entry *btree1;
+ struct xfs_da_node_entry *btree2;
+ struct xfs_da_node_entry *btree_s;
+ struct xfs_da_node_entry *btree_d;
+ struct xfs_da3_icnode_hdr nodehdr1;
+ struct xfs_da3_icnode_hdr nodehdr2;
+ struct xfs_trans *tp;
+ int count;
+ int tmp;
+ int swap = 0;
+ struct xfs_inode *dp = state->args->dp;
+
+ trace_xfs_da_node_rebalance(state->args);
+
+ node1 = blk1->bp->b_addr;
+ node2 = blk2->bp->b_addr;
+ dp->d_ops->node_hdr_from_disk(&nodehdr1, node1);
+ dp->d_ops->node_hdr_from_disk(&nodehdr2, node2);
+ btree1 = dp->d_ops->node_tree_p(node1);
+ btree2 = dp->d_ops->node_tree_p(node2);
+
+ /*
+ * Figure out how many entries need to move, and in which direction.
+ * Swap the nodes around if that makes it simpler.
+ */
+ if (nodehdr1.count > 0 && nodehdr2.count > 0 &&
+ ((be32_to_cpu(btree2[0].hashval) < be32_to_cpu(btree1[0].hashval)) ||
+ (be32_to_cpu(btree2[nodehdr2.count - 1].hashval) <
+ be32_to_cpu(btree1[nodehdr1.count - 1].hashval)))) {
+ tmpnode = node1;
+ node1 = node2;
+ node2 = tmpnode;
+ dp->d_ops->node_hdr_from_disk(&nodehdr1, node1);
+ dp->d_ops->node_hdr_from_disk(&nodehdr2, node2);
+ btree1 = dp->d_ops->node_tree_p(node1);
+ btree2 = dp->d_ops->node_tree_p(node2);
+ swap = 1;
+ }
+
+ count = (nodehdr1.count - nodehdr2.count) / 2;
+ if (count == 0)
+ return;
+ tp = state->args->trans;
+ /*
+ * Two cases: high-to-low and low-to-high.
+ */
+ if (count > 0) {
+ /*
+ * Move elements in node2 up to make a hole.
+ */
+ tmp = nodehdr2.count;
+ if (tmp > 0) {
+ tmp *= (uint)sizeof(xfs_da_node_entry_t);
+ btree_s = &btree2[0];
+ btree_d = &btree2[count];
+ memmove(btree_d, btree_s, tmp);
+ }
+
+ /*
+ * Move the req'd B-tree elements from high in node1 to
+ * low in node2.
+ */
+ nodehdr2.count += count;
+ tmp = count * (uint)sizeof(xfs_da_node_entry_t);
+ btree_s = &btree1[nodehdr1.count - count];
+ btree_d = &btree2[0];
+ memcpy(btree_d, btree_s, tmp);
+ nodehdr1.count -= count;
+ } else {
+ /*
+ * Move the req'd B-tree elements from low in node2 to
+ * high in node1.
+ */
+ count = -count;
+ tmp = count * (uint)sizeof(xfs_da_node_entry_t);
+ btree_s = &btree2[0];
+ btree_d = &btree1[nodehdr1.count];
+ memcpy(btree_d, btree_s, tmp);
+ nodehdr1.count += count;
+
+ xfs_trans_log_buf(tp, blk1->bp,
+ XFS_DA_LOGRANGE(node1, btree_d, tmp));
+
+ /*
+ * Move elements in node2 down to fill the hole.
+ */
+ tmp = nodehdr2.count - count;
+ tmp *= (uint)sizeof(xfs_da_node_entry_t);
+ btree_s = &btree2[count];
+ btree_d = &btree2[0];
+ memmove(btree_d, btree_s, tmp);
+ nodehdr2.count -= count;
+ }
+
+ /*
+ * Log header of node 1 and all current bits of node 2.
+ */
+ dp->d_ops->node_hdr_to_disk(node1, &nodehdr1);
+ xfs_trans_log_buf(tp, blk1->bp,
+ XFS_DA_LOGRANGE(node1, &node1->hdr, dp->d_ops->node_hdr_size));
+
+ dp->d_ops->node_hdr_to_disk(node2, &nodehdr2);
+ xfs_trans_log_buf(tp, blk2->bp,
+ XFS_DA_LOGRANGE(node2, &node2->hdr,
+ dp->d_ops->node_hdr_size +
+ (sizeof(btree2[0]) * nodehdr2.count)));
+
+ /*
+ * Record the last hashval from each block for upward propagation.
+ * (note: don't use the swapped node pointers)
+ */
+ if (swap) {
+ node1 = blk1->bp->b_addr;
+ node2 = blk2->bp->b_addr;
+ dp->d_ops->node_hdr_from_disk(&nodehdr1, node1);
+ dp->d_ops->node_hdr_from_disk(&nodehdr2, node2);
+ btree1 = dp->d_ops->node_tree_p(node1);
+ btree2 = dp->d_ops->node_tree_p(node2);
+ }
+ blk1->hashval = be32_to_cpu(btree1[nodehdr1.count - 1].hashval);
+ blk2->hashval = be32_to_cpu(btree2[nodehdr2.count - 1].hashval);
+
+ /*
+ * Adjust the expected index for insertion.
+ */
+ if (blk1->index >= nodehdr1.count) {
+ blk2->index = blk1->index - nodehdr1.count;
+ blk1->index = nodehdr1.count + 1; /* make it invalid */
+ }
+}
+
+/*
+ * Add a new entry to an intermediate node.
+ */
+STATIC void
+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->args->geo->leafblk &&
+ newblk->blkno < state->args->geo->freeblk);
+
+ /*
+ * 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);
+}
+
+/*========================================================================
+ * Routines used for shrinking the Btree.
+ *========================================================================*/
+
+/*
+ * Deallocate an empty leaf node, remove it from its parent,
+ * possibly deallocating that block, etc...
+ */
+int
+xfs_da3_join(
+ struct xfs_da_state *state)
+{
+ struct xfs_da_state_blk *drop_blk;
+ struct xfs_da_state_blk *save_blk;
+ int action = 0;
+ int error;
+
+ trace_xfs_da_join(state->args);
+
+ drop_blk = &state->path.blk[ state->path.active-1 ];
+ save_blk = &state->altpath.blk[ state->path.active-1 ];
+ ASSERT(state->path.blk[0].magic == XFS_DA_NODE_MAGIC);
+ ASSERT(drop_blk->magic == XFS_ATTR_LEAF_MAGIC ||
+ drop_blk->magic == XFS_DIR2_LEAFN_MAGIC);
+
+ /*
+ * Walk back up the tree joining/deallocating as necessary.
+ * When we stop dropping blocks, break out.
+ */
+ for ( ; state->path.active >= 2; drop_blk--, save_blk--,
+ state->path.active--) {
+ /*
+ * See if we can combine the block with a neighbor.
+ * (action == 0) => no options, just leave
+ * (action == 1) => coalesce, then unlink
+ * (action == 2) => block empty, unlink it
+ */
+ switch (drop_blk->magic) {
+ case XFS_ATTR_LEAF_MAGIC:
+ error = xfs_attr3_leaf_toosmall(state, &action);
+ if (error)
+ return error;
+ if (action == 0)
+ return 0;
+ xfs_attr3_leaf_unbalance(state, drop_blk, save_blk);
+ break;
+ case XFS_DIR2_LEAFN_MAGIC:
+ error = xfs_dir2_leafn_toosmall(state, &action);
+ if (error)
+ return error;
+ if (action == 0)
+ return 0;
+ xfs_dir2_leafn_unbalance(state, drop_blk, save_blk);
+ break;
+ case XFS_DA_NODE_MAGIC:
+ /*
+ * Remove the offending node, fixup hashvals,
+ * check for a toosmall neighbor.
+ */
+ xfs_da3_node_remove(state, drop_blk);
+ xfs_da3_fixhashpath(state, &state->path);
+ error = xfs_da3_node_toosmall(state, &action);
+ if (error)
+ return error;
+ if (action == 0)
+ return 0;
+ xfs_da3_node_unbalance(state, drop_blk, save_blk);
+ break;
+ }
+ xfs_da3_fixhashpath(state, &state->altpath);
+ error = xfs_da3_blk_unlink(state, drop_blk, save_blk);
+ xfs_da_state_kill_altpath(state);
+ if (error)
+ return error;
+ error = xfs_da_shrink_inode(state->args, drop_blk->blkno,
+ drop_blk->bp);
+ drop_blk->bp = NULL;
+ if (error)
+ return error;
+ }
+ /*
+ * We joined all the way to the top. If it turns out that
+ * we only have one entry in the root, make the child block
+ * the new root.
+ */
+ xfs_da3_node_remove(state, drop_blk);
+ xfs_da3_fixhashpath(state, &state->path);
+ error = xfs_da3_root_join(state, &state->path.blk[0]);
+ return error;
+}
+
+#ifdef DEBUG
+static void
+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);
+}
+#else /* !DEBUG */
+#define xfs_da_blkinfo_onlychild_validate(blkinfo, level)
+#endif /* !DEBUG */
+
+/*
+ * We have only one entry in the root. Copy the only remaining child of
+ * the old root to block 0 as the new root node.
+ */
+STATIC int
+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, args->geo->blksize);
+ 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,
+ args->geo->blksize - 1);
+ error = xfs_da_shrink_inode(args, child, bp);
+ return error;
+}
+
+/*
+ * Check a node block and its neighbors to see if the block should be
+ * collapsed into one or the other neighbor. Always keep the block
+ * with the smaller block number.
+ * If the current block is over 50% full, don't try to join it, return 0.
+ * If the block is empty, fill in the state structure and return 2.
+ * If it can be collapsed, fill in the state structure and return 1.
+ * If nothing can be done, return 0.
+ */
+STATIC int
+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->args->geo->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->args->geo->node_ents;
+ count -= state->args->geo->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;
+}
+
+/*
+ * Pick up the last hashvalue from an intermediate node.
+ */
+STATIC uint
+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);
+}
+
+/*
+ * Walk back up the tree adjusting hash values as necessary,
+ * when we stop making changes, return.
+ */
+void
+xfs_da3_fixhashpath(
+ struct xfs_da_state *state,
+ struct xfs_da_state_path *path)
+{
+ struct xfs_da_state_blk *blk;
+ struct xfs_da_intnode *node;
+ struct xfs_da_node_entry *btree;
+ xfs_dahash_t lasthash=0;
+ int level;
+ int count;
+ struct xfs_inode *dp = state->args->dp;
+
+ trace_xfs_da_fixhashpath(state->args);
+
+ level = path->active-1;
+ blk = &path->blk[ level ];
+ switch (blk->magic) {
+ case XFS_ATTR_LEAF_MAGIC:
+ lasthash = xfs_attr_leaf_lasthash(blk->bp, &count);
+ if (count == 0)
+ return;
+ break;
+ case XFS_DIR2_LEAFN_MAGIC:
+ lasthash = xfs_dir2_leaf_lasthash(dp, blk->bp, &count);
+ if (count == 0)
+ return;
+ break;
+ case XFS_DA_NODE_MAGIC:
+ lasthash = xfs_da3_node_lasthash(dp, blk->bp, &count);
+ if (count == 0)
+ return;
+ break;
+ }
+ for (blk--, level--; level >= 0; blk--, level--) {
+ struct xfs_da3_icnode_hdr nodehdr;
+
+ node = blk->bp->b_addr;
+ dp->d_ops->node_hdr_from_disk(&nodehdr, node);
+ btree = dp->d_ops->node_tree_p(node);
+ if (be32_to_cpu(btree[blk->index].hashval) == lasthash)
+ break;
+ blk->hashval = lasthash;
+ btree[blk->index].hashval = cpu_to_be32(lasthash);
+ xfs_trans_log_buf(state->args->trans, blk->bp,
+ XFS_DA_LOGRANGE(node, &btree[blk->index],
+ sizeof(*btree)));
+
+ lasthash = be32_to_cpu(btree[nodehdr.count - 1].hashval);
+ }
+}
+
+/*
+ * Remove an entry from an intermediate node.
+ */
+STATIC void
+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);
+}
+
+/*
+ * Unbalance the elements between two intermediate nodes,
+ * move all Btree elements from one node into another.
+ */
+STATIC void
+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);
+}
+
+/*========================================================================
+ * Routines used for finding things in the Btree.
+ *========================================================================*/
+
+/*
+ * Walk down the Btree looking for a particular filename, filling
+ * in the state structure as we go.
+ *
+ * We will set the state structure to point to each of the elements
+ * in each of the nodes where either the hashval is or should be.
+ *
+ * We support duplicate hashval's so for each entry in the current
+ * node that could contain the desired hashval, descend. This is a
+ * pruned depth-first tree search.
+ */
+int /* error */
+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;
+ unsigned int expected_level = 0;
+ uint16_t magic;
+ 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->geo->leafblk;
+ 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;
+ magic = be16_to_cpu(curr->magic);
+
+ if (magic == XFS_ATTR_LEAF_MAGIC ||
+ magic == XFS_ATTR3_LEAF_MAGIC) {
+ blk->magic = XFS_ATTR_LEAF_MAGIC;
+ blk->hashval = xfs_attr_leaf_lasthash(blk->bp, NULL);
+ break;
+ }
+
+ if (magic == XFS_DIR2_LEAFN_MAGIC ||
+ magic == XFS_DIR3_LEAFN_MAGIC) {
+ blk->magic = XFS_DIR2_LEAFN_MAGIC;
+ blk->hashval = xfs_dir2_leaf_lasthash(args->dp,
+ blk->bp, NULL);
+ break;
+ }
+
+ if (magic != XFS_DA_NODE_MAGIC && magic != XFS_DA3_NODE_MAGIC) {
+ xfs_buf_mark_corrupt(blk->bp);
+ return -EFSCORRUPTED;
+ }
+
+ 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);
+
+ /* Tree taller than we can handle; bail out! */
+ if (nodehdr.level >= XFS_DA_NODE_MAXDEPTH) {
+ xfs_buf_mark_corrupt(blk->bp);
+ return -EFSCORRUPTED;
+ }
+
+ /* Check the level from the root. */
+ if (blkno == args->geo->leafblk)
+ expected_level = nodehdr.level - 1;
+ else if (expected_level != nodehdr.level) {
+ xfs_buf_mark_corrupt(blk->bp);
+ return -EFSCORRUPTED;
+ } else
+ expected_level--;
+
+ 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);
+ }
+
+ /* We can't point back to the root. */
+ if (blkno == args->geo->leafblk) {
+ XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW,
+ dp->i_mount);
+ return -EFSCORRUPTED;
+ }
+ }
+
+ if (expected_level != 0) {
+ XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, dp->i_mount);
+ return -EFSCORRUPTED;
+ }
+
+ /*
+ * 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 -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 = -ENOATTR;
+ }
+ }
+ break;
+ }
+ *result = retval;
+ return 0;
+}
+
+/*========================================================================
+ * Utility routines.
+ *========================================================================*/
+
+/*
+ * Compare two intermediate nodes for "order".
+ */
+STATIC int
+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;
+}
+
+/*
+ * Link a new block into a doubly linked list of blocks (of whatever type).
+ */
+int /* error */
+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;
+}
+
+/*
+ * Unlink a block from a doubly linked list of blocks.
+ */
+STATIC int /* error */
+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;
+}
+
+/*
+ * Move a path "forward" or "!forward" one block at the current level.
+ *
+ * This routine will adjust a "path" to point to the next block
+ * "forward" (higher hashvalues) or "!forward" (lower hashvals) in the
+ * Btree, including updating pointers to the intermediate nodes between
+ * the new bottom and the root.
+ */
+int /* error */
+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;
+ struct xfs_buf *bp;
+ 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 = -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++) {
+ /*
+ * Read the next child block into a local buffer.
+ */
+ error = xfs_da3_node_read(args->trans, dp, blkno, -1, &bp,
+ args->whichfork);
+ if (error)
+ return error;
+
+ /*
+ * 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;
+ 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) ||
+ 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_leaf_lasthash(args->dp,
+ blk->bp, NULL);
+ break;
+ default:
+ ASSERT(0);
+ break;
+ }
+ }
+ *result = 0;
+ return 0;
+}
+
+
+/*========================================================================
+ * Utility routines.
+ *========================================================================*/
+
+/*
+ * Implement a simple hash on a character string.
+ * Rotate the hash value by 7 bits, then XOR each character in.
+ * This is implemented with some source-level loop unrolling.
+ */
+xfs_dahash_t
+xfs_da_hashname(const uint8_t *name, int namelen)
+{
+ xfs_dahash_t hash;
+
+ /*
+ * Do four characters at a time as long as we can.
+ */
+ for (hash = 0; namelen >= 4; namelen -= 4, name += 4)
+ hash = (name[0] << 21) ^ (name[1] << 14) ^ (name[2] << 7) ^
+ (name[3] << 0) ^ rol32(hash, 7 * 4);
+
+ /*
+ * Now do the rest of the characters.
+ */
+ switch (namelen) {
+ case 3:
+ return (name[0] << 14) ^ (name[1] << 7) ^ (name[2] << 0) ^
+ rol32(hash, 7 * 3);
+ case 2:
+ return (name[0] << 7) ^ (name[1] << 0) ^ rol32(hash, 7 * 2);
+ case 1:
+ return (name[0] << 0) ^ rol32(hash, 7 * 1);
+ default: /* case 0: */
+ return hash;
+ }
+}
+
+enum xfs_dacmp
+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;
+}
+
+static xfs_dahash_t
+xfs_default_hashname(
+ struct xfs_name *name)
+{
+ return xfs_da_hashname(name->name, name->len);
+}
+
+const struct xfs_nameops xfs_default_nameops = {
+ .hashname = xfs_default_hashname,
+ .compname = xfs_da_compname
+};
+
+int
+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_rfsblock_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;
+ error = xfs_bmapi_write(tp, dp, *bno, count,
+ xfs_bmapi_aflag(w)|XFS_BMAPI_METADATA|XFS_BMAPI_CONTIG,
+ args->total, &map, &nmap);
+ if (error)
+ return error;
+
+ ASSERT(nmap <= 1);
+ if (nmap == 1) {
+ mapp = ↦
+ 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, 0);
+ 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->total, &mapp[mapi], &nmap);
+ 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 = -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;
+}
+
+/*
+ * Add a block to the btree ahead of the file.
+ * Return the new block number to the caller.
+ */
+int
+xfs_da_grow_inode(
+ struct xfs_da_args *args,
+ xfs_dablk_t *new_blkno)
+{
+ xfs_fileoff_t bno;
+ int error;
+
+ trace_xfs_da_grow_inode(args);
+
+ bno = args->geo->leafblk;
+ error = xfs_da_grow_inode_int(args, &bno, args->geo->fsbcount);
+ if (!error)
+ *new_blkno = (xfs_dablk_t)bno;
+ return error;
+}
+
+/*
+ * Ick. We need to always be able to remove a btree block, even
+ * if there's no space reservation because the filesystem is full.
+ * This is called if xfs_bunmapi on a btree block fails due to ENOSPC.
+ * It swaps the target block with the last block in the file. The
+ * last block in the file can always be removed since it can't cause
+ * a bmap btree split to do that.
+ */
+STATIC int
+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 = args->geo->freeblk;
+ 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 -EFSCORRUPTED;
+ }
+ /*
+ * Read the last block in the btree space.
+ */
+ last_blkno = (xfs_dablk_t)lastoff - args->geo->fsbcount;
+ 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, args->geo->blksize);
+ xfs_trans_log_buf(tp, dead_buf, 0, args->geo->blksize - 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 = -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 = -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 = args->geo->leafblk;
+ 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 = -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 = -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 = -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 = -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;
+}
+
+/*
+ * Remove a btree block from a directory or attribute.
+ */
+int
+xfs_da_shrink_inode(
+ struct xfs_da_args *args,
+ xfs_dablk_t dead_blkno,
+ struct xfs_buf *dead_buf)
+{
+ struct xfs_inode *dp;
+ int done, error, w, count;
+ struct xfs_trans *tp;
+
+ trace_xfs_da_shrink_inode(args);
+
+ dp = args->dp;
+ w = args->whichfork;
+ tp = args->trans;
+ count = args->geo->fsbcount;
+ 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), 0, &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;
+}
+
+/*
+ * See if the mapping(s) for this btree block are valid, i.e.
+ * don't contain holes, are logically contiguous, and cover the whole range.
+ */
+STATIC int
+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;
+}
+
+/*
+ * Convert a struct xfs_bmbt_irec to a struct xfs_buf_map.
+ *
+ * For the single map case, it is assumed that the caller has provided a pointer
+ * to a valid xfs_buf_map. For the multiple map case, this function will
+ * allocate the xfs_buf_map to hold all the maps and replace the caller's single
+ * map pointer with the allocated map.
+ */
+static int
+xfs_buf_map_from_irec(
+ struct xfs_mount *mp,
+ struct xfs_buf_map **mapp,
+ int *nmaps,
+ struct xfs_bmbt_irec *irecs,
+ int nirecs)
+{
+ struct xfs_buf_map *map;
+ int i;
+
+ ASSERT(*nmaps == 1);
+ ASSERT(nirecs >= 1);
+
+ if (nirecs > 1) {
+ map = kmem_zalloc(nirecs * sizeof(struct xfs_buf_map),
+ KM_NOFS);
+ if (!map)
+ return -ENOMEM;
+ *mapp = map;
+ }
+
+ *nmaps = nirecs;
+ map = *mapp;
+ for (i = 0; i < *nmaps; i++) {
+ ASSERT(irecs[i].br_startblock != DELAYSTARTBLOCK &&
+ irecs[i].br_startblock != HOLESTARTBLOCK);
+ map[i].bm_bn = XFS_FSB_TO_DADDR(mp, irecs[i].br_startblock);
+ map[i].bm_len = XFS_FSB_TO_BB(mp, irecs[i].br_blockcount);
+ }
+ return 0;
+}
+
+/*
+ * Map the block we are given ready for reading. There are three possible return
+ * values:
+ * -1 - will be returned if we land in a hole and mappedbno == -2 so the
+ * caller knows not to execute a subsequent read.
+ * 0 - if we mapped the block successfully
+ * >0 - positive error number if there was an error.
+ */
+static int
+xfs_dabuf_map(
+ 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);
+
+ if (whichfork == XFS_DATA_FORK)
+ nfsb = mp->m_dir_geo->fsbcount;
+ else
+ nfsb = mp->m_attr_geo->fsbcount;
+
+ /*
+ * 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_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 : -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;
+}
+
+/*
+ * Get a buffer for the dir/attr block.
+ */
+int
+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 = ↦
+ nmap = 1;
+ error = xfs_dabuf_map(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 : -EIO;
+ if (error) {
+ if (bp)
+ xfs_trans_brelse(trans, bp);
+ goto out_free;
+ }
+
+ *bpp = bp;
+
+out_free:
+ if (mapp != &map)
+ kmem_free(mapp);
+
+ return error;
+}
+
+/*
+ * Get a buffer for the dir/attr block, fill in the contents.
+ */
+int
+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 = ↦
+ nmap = 1;
+ error = xfs_dabuf_map(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);
+ *bpp = bp;
+out_free:
+ if (mapp != &map)
+ kmem_free(mapp);
+
+ return error;
+}
+
+/*
+ * Readahead the dir/attr block.
+ */
+int
+xfs_da_reada_buf(
+ 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 = ↦
+ nmap = 1;
+ error = xfs_dabuf_map(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);
+
+ return error;
+}