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linux/fs/xfs/xfs_da_btree.c
Christoph Hellwig b4e9181e77 xfs: remove unused delta tracking code in xfs_bmapi 
This code was introduced four years ago in commit
3e57ecf640 without any review and has
been unused since.  Remove it just as the rest of the code introduced
in that commit to reduce that stack usage and complexity in this central
piece of code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-07-26 13:16:39 -05:00

2467 lines
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/*
* Copyright (c) 2000-2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir2.h"
#include "xfs_mount.h"
#include "xfs_da_btree.h"
#include "xfs_bmap_btree.h"
#include "xfs_dir2_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_inode_item.h"
#include "xfs_alloc.h"
#include "xfs_bmap.h"
#include "xfs_attr.h"
#include "xfs_attr_leaf.h"
#include "xfs_dir2_data.h"
#include "xfs_dir2_leaf.h"
#include "xfs_dir2_block.h"
#include "xfs_dir2_node.h"
#include "xfs_error.h"
#include "xfs_trace.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_da_root_split(xfs_da_state_t *state,
xfs_da_state_blk_t *existing_root,
xfs_da_state_blk_t *new_child);
STATIC int xfs_da_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_da_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_da_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_da_root_join(xfs_da_state_t *state,
xfs_da_state_blk_t *root_blk);
STATIC int xfs_da_node_toosmall(xfs_da_state_t *state, int *retval);
STATIC void xfs_da_node_remove(xfs_da_state_t *state,
xfs_da_state_blk_t *drop_blk);
STATIC void xfs_da_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 uint xfs_da_node_lasthash(xfs_dabuf_t *bp, int *count);
STATIC int xfs_da_node_order(xfs_dabuf_t *node1_bp, xfs_dabuf_t *node2_bp);
STATIC xfs_dabuf_t *xfs_da_buf_make(int nbuf, xfs_buf_t **bps, inst_t *ra);
STATIC int xfs_da_blk_unlink(xfs_da_state_t *state,
xfs_da_state_blk_t *drop_blk,
xfs_da_state_blk_t *save_blk);
STATIC void xfs_da_state_kill_altpath(xfs_da_state_t *state);
/*========================================================================
* Routines used for growing the Btree.
*========================================================================*/
/*
* Create the initial contents of an intermediate node.
*/
int
xfs_da_node_create(xfs_da_args_t *args, xfs_dablk_t blkno, int level,
xfs_dabuf_t **bpp, int whichfork)
{
xfs_da_intnode_t *node;
xfs_dabuf_t *bp;
int error;
xfs_trans_t *tp;
tp = args->trans;
error = xfs_da_get_buf(tp, args->dp, blkno, -1, &bp, whichfork);
if (error)
return(error);
ASSERT(bp != NULL);
node = bp->data;
node->hdr.info.forw = 0;
node->hdr.info.back = 0;
node->hdr.info.magic = cpu_to_be16(XFS_DA_NODE_MAGIC);
node->hdr.info.pad = 0;
node->hdr.count = 0;
node->hdr.level = cpu_to_be16(level);
xfs_da_log_buf(tp, bp,
XFS_DA_LOGRANGE(node, &node->hdr, sizeof(node->hdr)));
*bpp = bp;
return(0);
}
/*
* Split a leaf node, rebalance, then possibly split
* intermediate nodes, rebalance, etc.
*/
int /* error */
xfs_da_split(xfs_da_state_t *state)
{
xfs_da_state_blk_t *oldblk, *newblk, *addblk;
xfs_da_intnode_t *node;
xfs_dabuf_t *bp;
int max, action, error, i;
/*
* 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_attr_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 */
error = xfs_attr_leaf_split(state, oldblk,
&state->extrablk);
} else {
state->extraafter = 1; /* after newblk */
error = xfs_attr_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_da_node_split(state, oldblk, newblk, addblk,
max - i, &action);
xfs_da_buf_done(addblk->bp);
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_da_fixhashpath(state, &state->path);
/*
* If we won't need this block again, it's getting dropped
* from the active path by the loop control, so we need
* to mark it done now.
*/
if (i > 0 || !addblk)
xfs_da_buf_done(oldblk->bp);
}
if (!addblk)
return(0);
/*
* Split the root node.
*/
ASSERT(state->path.active == 0);
oldblk = &state->path.blk[0];
error = xfs_da_root_split(state, oldblk, addblk);
if (error) {
xfs_da_buf_done(oldblk->bp);
xfs_da_buf_done(addblk->bp);
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.
*/
node = oldblk->bp->data;
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->data;
node->hdr.info.back = cpu_to_be32(oldblk->blkno);
xfs_da_log_buf(state->args->trans, bp,
XFS_DA_LOGRANGE(node, &node->hdr.info,
sizeof(node->hdr.info)));
}
node = oldblk->bp->data;
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->data;
node->hdr.info.forw = cpu_to_be32(oldblk->blkno);
xfs_da_log_buf(state->args->trans, bp,
XFS_DA_LOGRANGE(node, &node->hdr.info,
sizeof(node->hdr.info)));
}
xfs_da_buf_done(oldblk->bp);
xfs_da_buf_done(addblk->bp);
addblk->bp = NULL;
return(0);
}
/*
* 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_da_root_split(xfs_da_state_t *state, xfs_da_state_blk_t *blk1,
xfs_da_state_blk_t *blk2)
{
xfs_da_intnode_t *node, *oldroot;
xfs_da_args_t *args;
xfs_dablk_t blkno;
xfs_dabuf_t *bp;
int error, size;
xfs_inode_t *dp;
xfs_trans_t *tp;
xfs_mount_t *mp;
xfs_dir2_leaf_t *leaf;
/*
* Copy the existing (incorrect) block from the root node position
* to a free space somewhere.
*/
args = state->args;
ASSERT(args != NULL);
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);
ASSERT(bp != NULL);
node = bp->data;
oldroot = blk1->bp->data;
if (be16_to_cpu(oldroot->hdr.info.magic) == XFS_DA_NODE_MAGIC) {
size = (int)((char *)&oldroot->btree[be16_to_cpu(oldroot->hdr.count)] -
(char *)oldroot);
} else {
ASSERT(be16_to_cpu(oldroot->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
leaf = (xfs_dir2_leaf_t *)oldroot;
size = (int)((char *)&leaf->ents[be16_to_cpu(leaf->hdr.count)] -
(char *)leaf);
}
memcpy(node, oldroot, size);
xfs_da_log_buf(tp, bp, 0, size - 1);
xfs_da_buf_done(blk1->bp);
blk1->bp = bp;
blk1->blkno = blkno;
/*
* Set up the new root node.
*/
error = xfs_da_node_create(args,
(args->whichfork == XFS_DATA_FORK) ? mp->m_dirleafblk : 0,
be16_to_cpu(node->hdr.level) + 1, &bp, args->whichfork);
if (error)
return(error);
node = bp->data;
node->btree[0].hashval = cpu_to_be32(blk1->hashval);
node->btree[0].before = cpu_to_be32(blk1->blkno);
node->btree[1].hashval = cpu_to_be32(blk2->hashval);
node->btree[1].before = cpu_to_be32(blk2->blkno);
node->hdr.count = cpu_to_be16(2);
#ifdef DEBUG
if (be16_to_cpu(oldroot->hdr.info.magic) == XFS_DIR2_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_da_log_buf(tp, bp,
XFS_DA_LOGRANGE(node, node->btree,
sizeof(xfs_da_node_entry_t) * 2));
xfs_da_buf_done(bp);
return(0);
}
/*
* Split the node, rebalance, then add the new entry.
*/
STATIC int /* error */
xfs_da_node_split(xfs_da_state_t *state, xfs_da_state_blk_t *oldblk,
xfs_da_state_blk_t *newblk,
xfs_da_state_blk_t *addblk,
int treelevel, int *result)
{
xfs_da_intnode_t *node;
xfs_dablk_t blkno;
int newcount, error;
int useextra;
node = oldblk->bp->data;
ASSERT(be16_to_cpu(node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
/*
* 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 ((be16_to_cpu(node->hdr.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_da_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_da_node_rebalance(state, oldblk, newblk);
error = xfs_da_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_da_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->data;
if (oldblk->index <= be16_to_cpu(node->hdr.count)) {
oldblk->index++;
xfs_da_node_add(state, oldblk, addblk);
if (useextra) {
if (state->extraafter)
oldblk->index++;
xfs_da_node_add(state, oldblk, &state->extrablk);
state->extravalid = 0;
}
} else {
newblk->index++;
xfs_da_node_add(state, newblk, addblk);
if (useextra) {
if (state->extraafter)
newblk->index++;
xfs_da_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_da_node_rebalance(xfs_da_state_t *state, xfs_da_state_blk_t *blk1,
xfs_da_state_blk_t *blk2)
{
xfs_da_intnode_t *node1, *node2, *tmpnode;
xfs_da_node_entry_t *btree_s, *btree_d;
int count, tmp;
xfs_trans_t *tp;
node1 = blk1->bp->data;
node2 = blk2->bp->data;
/*
* Figure out how many entries need to move, and in which direction.
* Swap the nodes around if that makes it simpler.
*/
if ((be16_to_cpu(node1->hdr.count) > 0) && (be16_to_cpu(node2->hdr.count) > 0) &&
((be32_to_cpu(node2->btree[0].hashval) < be32_to_cpu(node1->btree[0].hashval)) ||
(be32_to_cpu(node2->btree[be16_to_cpu(node2->hdr.count)-1].hashval) <
be32_to_cpu(node1->btree[be16_to_cpu(node1->hdr.count)-1].hashval)))) {
tmpnode = node1;
node1 = node2;
node2 = tmpnode;
}
ASSERT(be16_to_cpu(node1->hdr.info.magic) == XFS_DA_NODE_MAGIC);
ASSERT(be16_to_cpu(node2->hdr.info.magic) == XFS_DA_NODE_MAGIC);
count = (be16_to_cpu(node1->hdr.count) - be16_to_cpu(node2->hdr.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.
*/
if ((tmp = be16_to_cpu(node2->hdr.count)) > 0) {
tmp *= (uint)sizeof(xfs_da_node_entry_t);
btree_s = &node2->btree[0];
btree_d = &node2->btree[count];
memmove(btree_d, btree_s, tmp);
}
/*
* Move the req'd B-tree elements from high in node1 to
* low in node2.
*/
be16_add_cpu(&node2->hdr.count, count);
tmp = count * (uint)sizeof(xfs_da_node_entry_t);
btree_s = &node1->btree[be16_to_cpu(node1->hdr.count) - count];
btree_d = &node2->btree[0];
memcpy(btree_d, btree_s, tmp);
be16_add_cpu(&node1->hdr.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 = &node2->btree[0];
btree_d = &node1->btree[be16_to_cpu(node1->hdr.count)];
memcpy(btree_d, btree_s, tmp);
be16_add_cpu(&node1->hdr.count, count);
xfs_da_log_buf(tp, blk1->bp,
XFS_DA_LOGRANGE(node1, btree_d, tmp));
/*
* Move elements in node2 down to fill the hole.
*/
tmp = be16_to_cpu(node2->hdr.count) - count;
tmp *= (uint)sizeof(xfs_da_node_entry_t);
btree_s = &node2->btree[count];
btree_d = &node2->btree[0];
memmove(btree_d, btree_s, tmp);
be16_add_cpu(&node2->hdr.count, -count);
}
/*
* Log header of node 1 and all current bits of node 2.
*/
xfs_da_log_buf(tp, blk1->bp,
XFS_DA_LOGRANGE(node1, &node1->hdr, sizeof(node1->hdr)));
xfs_da_log_buf(tp, blk2->bp,
XFS_DA_LOGRANGE(node2, &node2->hdr,
sizeof(node2->hdr) +
sizeof(node2->btree[0]) * be16_to_cpu(node2->hdr.count)));
/*
* Record the last hashval from each block for upward propagation.
* (note: don't use the swapped node pointers)
*/
node1 = blk1->bp->data;
node2 = blk2->bp->data;
blk1->hashval = be32_to_cpu(node1->btree[be16_to_cpu(node1->hdr.count)-1].hashval);
blk2->hashval = be32_to_cpu(node2->btree[be16_to_cpu(node2->hdr.count)-1].hashval);
/*
* Adjust the expected index for insertion.
*/
if (blk1->index >= be16_to_cpu(node1->hdr.count)) {
blk2->index = blk1->index - be16_to_cpu(node1->hdr.count);
blk1->index = be16_to_cpu(node1->hdr.count) + 1; /* make it invalid */
}
}
/*
* Add a new entry to an intermediate node.
*/
STATIC void
xfs_da_node_add(xfs_da_state_t *state, xfs_da_state_blk_t *oldblk,
xfs_da_state_blk_t *newblk)
{
xfs_da_intnode_t *node;
xfs_da_node_entry_t *btree;
int tmp;
xfs_mount_t *mp;
node = oldblk->bp->data;
mp = state->mp;
ASSERT(be16_to_cpu(node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
ASSERT((oldblk->index >= 0) && (oldblk->index <= be16_to_cpu(node->hdr.count)));
ASSERT(newblk->blkno != 0);
if (state->args->whichfork == XFS_DATA_FORK)
ASSERT(newblk->blkno >= mp->m_dirleafblk &&
newblk->blkno < mp->m_dirfreeblk);
/*
* We may need to make some room before we insert the new node.
*/
tmp = 0;
btree = &node->btree[ oldblk->index ];
if (oldblk->index < be16_to_cpu(node->hdr.count)) {
tmp = (be16_to_cpu(node->hdr.count) - oldblk->index) * (uint)sizeof(*btree);
memmove(btree + 1, btree, tmp);
}
btree->hashval = cpu_to_be32(newblk->hashval);
btree->before = cpu_to_be32(newblk->blkno);
xfs_da_log_buf(state->args->trans, oldblk->bp,
XFS_DA_LOGRANGE(node, btree, tmp + sizeof(*btree)));
be16_add_cpu(&node->hdr.count, 1);
xfs_da_log_buf(state->args->trans, oldblk->bp,
XFS_DA_LOGRANGE(node, &node->hdr, sizeof(node->hdr)));
/*
* Copy the last hash value from the oldblk to propagate upwards.
*/
oldblk->hashval = be32_to_cpu(node->btree[be16_to_cpu(node->hdr.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_da_join(xfs_da_state_t *state)
{
xfs_da_state_blk_t *drop_blk, *save_blk;
int action, error;
action = 0;
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_attr_leaf_toosmall(state, &action);
if (error)
return(error);
if (action == 0)
return(0);
xfs_attr_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_da_node_remove(state, drop_blk);
xfs_da_fixhashpath(state, &state->path);
error = xfs_da_node_toosmall(state, &action);
if (error)
return(error);
if (action == 0)
return 0;
xfs_da_node_unbalance(state, drop_blk, save_blk);
break;
}
xfs_da_fixhashpath(state, &state->altpath);
error = xfs_da_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_da_node_remove(state, drop_blk);
xfs_da_fixhashpath(state, &state->path);
error = xfs_da_root_join(state, &state->path.blk[0]);
return(error);
}
/*
* 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_da_root_join(xfs_da_state_t *state, xfs_da_state_blk_t *root_blk)
{
xfs_da_intnode_t *oldroot;
/* REFERENCED */
xfs_da_blkinfo_t *blkinfo;
xfs_da_args_t *args;
xfs_dablk_t child;
xfs_dabuf_t *bp;
int error;
args = state->args;
ASSERT(args != NULL);
ASSERT(root_blk->magic == XFS_DA_NODE_MAGIC);
oldroot = root_blk->bp->data;
ASSERT(be16_to_cpu(oldroot->hdr.info.magic) == XFS_DA_NODE_MAGIC);
ASSERT(!oldroot->hdr.info.forw);
ASSERT(!oldroot->hdr.info.back);
/*
* If the root has more than one child, then don't do anything.
*/
if (be16_to_cpu(oldroot->hdr.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.
*/
child = be32_to_cpu(oldroot->btree[0].before);
ASSERT(child != 0);
error = xfs_da_read_buf(args->trans, args->dp, child, -1, &bp,
args->whichfork);
if (error)
return(error);
ASSERT(bp != NULL);
blkinfo = bp->data;
if (be16_to_cpu(oldroot->hdr.level) == 1) {
ASSERT(be16_to_cpu(blkinfo->magic) == XFS_DIR2_LEAFN_MAGIC ||
be16_to_cpu(blkinfo->magic) == XFS_ATTR_LEAF_MAGIC);
} else {
ASSERT(be16_to_cpu(blkinfo->magic) == XFS_DA_NODE_MAGIC);
}
ASSERT(!blkinfo->forw);
ASSERT(!blkinfo->back);
memcpy(root_blk->bp->data, bp->data, state->blocksize);
xfs_da_log_buf(args->trans, root_blk->bp, 0, state->blocksize - 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_da_node_toosmall(xfs_da_state_t *state, int *action)
{
xfs_da_intnode_t *node;
xfs_da_state_blk_t *blk;
xfs_da_blkinfo_t *info;
int count, forward, error, retval, i;
xfs_dablk_t blkno;
xfs_dabuf_t *bp;
/*
* 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->data;
ASSERT(be16_to_cpu(info->magic) == XFS_DA_NODE_MAGIC);
node = (xfs_da_intnode_t *)info;
count = be16_to_cpu(node->hdr.count);
if (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 (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_da_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.
*/
/* start with smaller blk num */
forward = (be32_to_cpu(info->forw) < be32_to_cpu(info->back));
for (i = 0; i < 2; forward = !forward, i++) {
if (forward)
blkno = be32_to_cpu(info->forw);
else
blkno = be32_to_cpu(info->back);
if (blkno == 0)
continue;
error = xfs_da_read_buf(state->args->trans, state->args->dp,
blkno, -1, &bp, state->args->whichfork);
if (error)
return(error);
ASSERT(bp != NULL);
node = (xfs_da_intnode_t *)info;
count = state->node_ents;
count -= state->node_ents >> 2;
count -= be16_to_cpu(node->hdr.count);
node = bp->data;
ASSERT(be16_to_cpu(node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
count -= be16_to_cpu(node->hdr.count);
xfs_da_brelse(state->args->trans, bp);
if (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_da_path_shift(state, &state->altpath, forward,
0, &retval);
if (error) {
return(error);
}
if (retval) {
*action = 0;
return(0);
}
} else {
error = xfs_da_path_shift(state, &state->path, forward,
0, &retval);
if (error) {
return(error);
}
if (retval) {
*action = 0;
return(0);
}
}
*action = 1;
return(0);
}
/*
* Walk back up the tree adjusting hash values as necessary,
* when we stop making changes, return.
*/
void
xfs_da_fixhashpath(xfs_da_state_t *state, xfs_da_state_path_t *path)
{
xfs_da_state_blk_t *blk;
xfs_da_intnode_t *node;
xfs_da_node_entry_t *btree;
xfs_dahash_t lasthash=0;
int level, count;
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_leafn_lasthash(blk->bp, &count);
if (count == 0)
return;
break;
case XFS_DA_NODE_MAGIC:
lasthash = xfs_da_node_lasthash(blk->bp, &count);
if (count == 0)
return;
break;
}
for (blk--, level--; level >= 0; blk--, level--) {
node = blk->bp->data;
ASSERT(be16_to_cpu(node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
btree = &node->btree[ blk->index ];
if (be32_to_cpu(btree->hashval) == lasthash)
break;
blk->hashval = lasthash;
btree->hashval = cpu_to_be32(lasthash);
xfs_da_log_buf(state->args->trans, blk->bp,
XFS_DA_LOGRANGE(node, btree, sizeof(*btree)));
lasthash = be32_to_cpu(node->btree[be16_to_cpu(node->hdr.count)-1].hashval);
}
}
/*
* Remove an entry from an intermediate node.
*/
STATIC void
xfs_da_node_remove(xfs_da_state_t *state, xfs_da_state_blk_t *drop_blk)
{
xfs_da_intnode_t *node;
xfs_da_node_entry_t *btree;
int tmp;
node = drop_blk->bp->data;
ASSERT(drop_blk->index < be16_to_cpu(node->hdr.count));
ASSERT(drop_blk->index >= 0);
/*
* Copy over the offending entry, or just zero it out.
*/
btree = &node->btree[drop_blk->index];
if (drop_blk->index < (be16_to_cpu(node->hdr.count)-1)) {
tmp = be16_to_cpu(node->hdr.count) - drop_blk->index - 1;
tmp *= (uint)sizeof(xfs_da_node_entry_t);
memmove(btree, btree + 1, tmp);
xfs_da_log_buf(state->args->trans, drop_blk->bp,
XFS_DA_LOGRANGE(node, btree, tmp));
btree = &node->btree[be16_to_cpu(node->hdr.count)-1];
}
memset((char *)btree, 0, sizeof(xfs_da_node_entry_t));
xfs_da_log_buf(state->args->trans, drop_blk->bp,
XFS_DA_LOGRANGE(node, btree, sizeof(*btree)));
be16_add_cpu(&node->hdr.count, -1);
xfs_da_log_buf(state->args->trans, drop_blk->bp,
XFS_DA_LOGRANGE(node, &node->hdr, sizeof(node->hdr)));
/*
* Copy the last hash value from the block to propagate upwards.
*/
btree--;
drop_blk->hashval = be32_to_cpu(btree->hashval);
}
/*
* Unbalance the btree elements between two intermediate nodes,
* move all Btree elements from one node into another.
*/
STATIC void
xfs_da_node_unbalance(xfs_da_state_t *state, xfs_da_state_blk_t *drop_blk,
xfs_da_state_blk_t *save_blk)
{
xfs_da_intnode_t *drop_node, *save_node;
xfs_da_node_entry_t *btree;
int tmp;
xfs_trans_t *tp;
drop_node = drop_blk->bp->data;
save_node = save_blk->bp->data;
ASSERT(be16_to_cpu(drop_node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
ASSERT(be16_to_cpu(save_node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
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_node->btree[0].hashval) < be32_to_cpu(save_node->btree[ 0 ].hashval)) ||
(be32_to_cpu(drop_node->btree[be16_to_cpu(drop_node->hdr.count)-1].hashval) <
be32_to_cpu(save_node->btree[be16_to_cpu(save_node->hdr.count)-1].hashval)))
{
btree = &save_node->btree[be16_to_cpu(drop_node->hdr.count)];
tmp = be16_to_cpu(save_node->hdr.count) * (uint)sizeof(xfs_da_node_entry_t);
memmove(btree, &save_node->btree[0], tmp);
btree = &save_node->btree[0];
xfs_da_log_buf(tp, save_blk->bp,
XFS_DA_LOGRANGE(save_node, btree,
(be16_to_cpu(save_node->hdr.count) + be16_to_cpu(drop_node->hdr.count)) *
sizeof(xfs_da_node_entry_t)));
} else {
btree = &save_node->btree[be16_to_cpu(save_node->hdr.count)];
xfs_da_log_buf(tp, save_blk->bp,
XFS_DA_LOGRANGE(save_node, btree,
be16_to_cpu(drop_node->hdr.count) *
sizeof(xfs_da_node_entry_t)));
}
/*
* Move all the B-tree elements from drop_blk to save_blk.
*/
tmp = be16_to_cpu(drop_node->hdr.count) * (uint)sizeof(xfs_da_node_entry_t);
memcpy(btree, &drop_node->btree[0], tmp);
be16_add_cpu(&save_node->hdr.count, be16_to_cpu(drop_node->hdr.count));
xfs_da_log_buf(tp, save_blk->bp,
XFS_DA_LOGRANGE(save_node, &save_node->hdr,
sizeof(save_node->hdr)));
/*
* Save the last hashval in the remaining block for upward propagation.
*/
save_blk->hashval = be32_to_cpu(save_node->btree[be16_to_cpu(save_node->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_da_node_lookup_int(xfs_da_state_t *state, int *result)
{
xfs_da_state_blk_t *blk;
xfs_da_blkinfo_t *curr;
xfs_da_intnode_t *node;
xfs_da_node_entry_t *btree;
xfs_dablk_t blkno;
int probe, span, max, error, retval;
xfs_dahash_t hashval, btreehashval;
xfs_da_args_t *args;
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_da_read_buf(args->trans, args->dp, blkno,
-1, &blk->bp, args->whichfork);
if (error) {
blk->blkno = 0;
state->path.active--;
return(error);
}
curr = blk->bp->data;
blk->magic = be16_to_cpu(curr->magic);
ASSERT(blk->magic == XFS_DA_NODE_MAGIC ||
blk->magic == XFS_DIR2_LEAFN_MAGIC ||
blk->magic == XFS_ATTR_LEAF_MAGIC);
/*
* Search an intermediate node for a match.
*/
if (blk->magic == XFS_DA_NODE_MAGIC) {
node = blk->bp->data;
max = be16_to_cpu(node->hdr.count);
blk->hashval = be32_to_cpu(node->btree[max-1].hashval);
/*
* Binary search. (note: small blocks will skip loop)
*/
probe = span = max / 2;
hashval = args->hashval;
for (btree = &node->btree[probe]; span > 4;
btree = &node->btree[probe]) {
span /= 2;
btreehashval = be32_to_cpu(btree->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->hashval) == hashval));
/*
* Since we may have duplicate hashval's, find the first
* matching hashval in the node.
*/
while ((probe > 0) && (be32_to_cpu(btree->hashval) >= hashval)) {
btree--;
probe--;
}
while ((probe < max) && (be32_to_cpu(btree->hashval) < hashval)) {
btree++;
probe++;
}
/*
* Pick the right block to descend on.
*/
if (probe == max) {
blk->index = max-1;
blkno = be32_to_cpu(node->btree[max-1].before);
} else {
blk->index = probe;
blkno = be32_to_cpu(btree->before);
}
} else if (blk->magic == XFS_ATTR_LEAF_MAGIC) {
blk->hashval = xfs_attr_leaf_lasthash(blk->bp, NULL);
break;
} else if (blk->magic == XFS_DIR2_LEAFN_MAGIC) {
blk->hashval = xfs_dir2_leafn_lasthash(blk->bp, NULL);
break;
}
}
/*
* 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_attr_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_da_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);
}
/*========================================================================
* Utility routines.
*========================================================================*/
/*
* Link a new block into a doubly linked list of blocks (of whatever type).
*/
int /* error */
xfs_da_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk,
xfs_da_state_blk_t *new_blk)
{
xfs_da_blkinfo_t *old_info, *new_info, *tmp_info;
xfs_da_args_t *args;
int before=0, error;
xfs_dabuf_t *bp;
/*
* Set up environment.
*/
args = state->args;
ASSERT(args != NULL);
old_info = old_blk->bp->data;
new_info = new_blk->bp->data;
ASSERT(old_blk->magic == XFS_DA_NODE_MAGIC ||
old_blk->magic == XFS_DIR2_LEAFN_MAGIC ||
old_blk->magic == XFS_ATTR_LEAF_MAGIC);
ASSERT(old_blk->magic == be16_to_cpu(old_info->magic));
ASSERT(new_blk->magic == be16_to_cpu(new_info->magic));
ASSERT(old_blk->magic == new_blk->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(old_blk->bp, new_blk->bp);
break;
case XFS_DA_NODE_MAGIC:
before = xfs_da_node_order(old_blk->bp, new_blk->bp);
break;
}
/*
* Link blocks in appropriate order.
*/
if (before) {
/*
* Link new block in before existing block.
*/
new_info->forw = cpu_to_be32(old_blk->blkno);
new_info->back = old_info->back;
if (old_info->back) {
error = xfs_da_read_buf(args->trans, args->dp,
be32_to_cpu(old_info->back),
-1, &bp, args->whichfork);
if (error)
return(error);
ASSERT(bp != NULL);
tmp_info = bp->data;
ASSERT(be16_to_cpu(tmp_info->magic) == be16_to_cpu(old_info->magic));
ASSERT(be32_to_cpu(tmp_info->forw) == old_blk->blkno);
tmp_info->forw = cpu_to_be32(new_blk->blkno);
xfs_da_log_buf(args->trans, bp, 0, sizeof(*tmp_info)-1);
xfs_da_buf_done(bp);
}
old_info->back = cpu_to_be32(new_blk->blkno);
} else {
/*
* Link new block in after existing block.
*/
new_info->forw = old_info->forw;
new_info->back = cpu_to_be32(old_blk->blkno);
if (old_info->forw) {
error = xfs_da_read_buf(args->trans, args->dp,
be32_to_cpu(old_info->forw),
-1, &bp, args->whichfork);
if (error)
return(error);
ASSERT(bp != NULL);
tmp_info = bp->data;
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_da_log_buf(args->trans, bp, 0, sizeof(*tmp_info)-1);
xfs_da_buf_done(bp);
}
old_info->forw = cpu_to_be32(new_blk->blkno);
}
xfs_da_log_buf(args->trans, old_blk->bp, 0, sizeof(*tmp_info) - 1);
xfs_da_log_buf(args->trans, new_blk->bp, 0, sizeof(*tmp_info) - 1);
return(0);
}
/*
* Compare two intermediate nodes for "order".
*/
STATIC int
xfs_da_node_order(xfs_dabuf_t *node1_bp, xfs_dabuf_t *node2_bp)
{
xfs_da_intnode_t *node1, *node2;
node1 = node1_bp->data;
node2 = node2_bp->data;
ASSERT((be16_to_cpu(node1->hdr.info.magic) == XFS_DA_NODE_MAGIC) &&
(be16_to_cpu(node2->hdr.info.magic) == XFS_DA_NODE_MAGIC));
if ((be16_to_cpu(node1->hdr.count) > 0) && (be16_to_cpu(node2->hdr.count) > 0) &&
((be32_to_cpu(node2->btree[0].hashval) <
be32_to_cpu(node1->btree[0].hashval)) ||
(be32_to_cpu(node2->btree[be16_to_cpu(node2->hdr.count)-1].hashval) <
be32_to_cpu(node1->btree[be16_to_cpu(node1->hdr.count)-1].hashval)))) {
return(1);
}
return(0);
}
/*
* Pick up the last hashvalue from an intermediate node.
*/
STATIC uint
xfs_da_node_lasthash(xfs_dabuf_t *bp, int *count)
{
xfs_da_intnode_t *node;
node = bp->data;
ASSERT(be16_to_cpu(node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
if (count)
*count = be16_to_cpu(node->hdr.count);
if (!node->hdr.count)
return(0);
return be32_to_cpu(node->btree[be16_to_cpu(node->hdr.count)-1].hashval);
}
/*
* Unlink a block from a doubly linked list of blocks.
*/
STATIC int /* error */
xfs_da_blk_unlink(xfs_da_state_t *state, xfs_da_state_blk_t *drop_blk,
xfs_da_state_blk_t *save_blk)
{
xfs_da_blkinfo_t *drop_info, *save_info, *tmp_info;
xfs_da_args_t *args;
xfs_dabuf_t *bp;
int error;
/*
* Set up environment.
*/
args = state->args;
ASSERT(args != NULL);
save_info = save_blk->bp->data;
drop_info = drop_blk->bp->data;
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 == be16_to_cpu(save_info->magic));
ASSERT(drop_blk->magic == be16_to_cpu(drop_info->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) {
save_info->back = drop_info->back;
if (drop_info->back) {
error = xfs_da_read_buf(args->trans, args->dp,
be32_to_cpu(drop_info->back),
-1, &bp, args->whichfork);
if (error)
return(error);
ASSERT(bp != NULL);
tmp_info = bp->data;
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_da_log_buf(args->trans, bp, 0,
sizeof(*tmp_info) - 1);
xfs_da_buf_done(bp);
}
} else {
save_info->forw = drop_info->forw;
if (drop_info->forw) {
error = xfs_da_read_buf(args->trans, args->dp,
be32_to_cpu(drop_info->forw),
-1, &bp, args->whichfork);
if (error)
return(error);
ASSERT(bp != NULL);
tmp_info = bp->data;
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_da_log_buf(args->trans, bp, 0,
sizeof(*tmp_info) - 1);
xfs_da_buf_done(bp);
}
}
xfs_da_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_da_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path,
int forward, int release, int *result)
{
xfs_da_state_blk_t *blk;
xfs_da_blkinfo_t *info;
xfs_da_intnode_t *node;
xfs_da_args_t *args;
xfs_dablk_t blkno=0;
int level, error;
/*
* 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--) {
ASSERT(blk->bp != NULL);
node = blk->bp->data;
ASSERT(be16_to_cpu(node->hdr.info.magic) == XFS_DA_NODE_MAGIC);
if (forward && (blk->index < be16_to_cpu(node->hdr.count)-1)) {
blk->index++;
blkno = be32_to_cpu(node->btree[blk->index].before);
break;
} else if (!forward && (blk->index > 0)) {
blk->index--;
blkno = be32_to_cpu(node->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_da_brelse(args->trans, blk->bp);
/*
* Read the next child block.
*/
blk->blkno = blkno;
error = xfs_da_read_buf(args->trans, args->dp, blkno, -1,
&blk->bp, args->whichfork);
if (error)
return(error);
ASSERT(blk->bp != NULL);
info = blk->bp->data;
ASSERT(be16_to_cpu(info->magic) == XFS_DA_NODE_MAGIC ||
be16_to_cpu(info->magic) == XFS_DIR2_LEAFN_MAGIC ||
be16_to_cpu(info->magic) == XFS_ATTR_LEAF_MAGIC);
blk->magic = be16_to_cpu(info->magic);
if (blk->magic == XFS_DA_NODE_MAGIC) {
node = (xfs_da_intnode_t *)info;
blk->hashval = be32_to_cpu(node->btree[be16_to_cpu(node->hdr.count)-1].hashval);
if (forward)
blk->index = 0;
else
blk->index = be16_to_cpu(node->hdr.count)-1;
blkno = be32_to_cpu(node->btree[blk->index].before);
} else {
ASSERT(level == path->active-1);
blk->index = 0;
switch(blk->magic) {
case XFS_ATTR_LEAF_MAGIC:
blk->hashval = xfs_attr_leaf_lasthash(blk->bp,
NULL);
break;
case XFS_DIR2_LEAFN_MAGIC:
blk->hashval = xfs_dir2_leafn_lasthash(blk->bp,
NULL);
break;
default:
ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC ||
blk->magic == XFS_DIR2_LEAFN_MAGIC);
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
};
/*
* Add a block to the btree ahead of the file.
* Return the new block number to the caller.
*/
int
xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno)
{
xfs_fileoff_t bno, b;
xfs_bmbt_irec_t map;
xfs_bmbt_irec_t *mapp;
xfs_inode_t *dp;
int nmap, error, w, count, c, got, i, mapi;
xfs_trans_t *tp;
xfs_mount_t *mp;
xfs_drfsbno_t nblks;
dp = args->dp;
mp = dp->i_mount;
w = args->whichfork;
tp = args->trans;
nblks = dp->i_d.di_nblocks;
/*
* For new directories adjust the file offset and block count.
*/
if (w == XFS_DATA_FORK) {
bno = mp->m_dirleafblk;
count = mp->m_dirblkfsbs;
} else {
bno = 0;
count = 1;
}
/*
* Find a spot in the file space to put the new block.
*/
if ((error = xfs_bmap_first_unused(tp, dp, count, &bno, w)))
return error;
if (w == XFS_DATA_FORK)
ASSERT(bno >= mp->m_dirleafblk && bno < mp->m_dirfreeblk);
/*
* Try mapping it in one filesystem block.
*/
nmap = 1;
ASSERT(args->firstblock != NULL);
if ((error = xfs_bmapi(tp, dp, bno, count,
xfs_bmapi_aflag(w)|XFS_BMAPI_WRITE|XFS_BMAPI_METADATA|
XFS_BMAPI_CONTIG,
args->firstblock, args->total, &map, &nmap,
args->flist))) {
return error;
}
ASSERT(nmap <= 1);
if (nmap == 1) {
mapp = &map;
mapi = 1;
}
/*
* If we didn't get it and the block might work if fragmented,
* try without the CONTIG flag. Loop until we get it all.
*/
else if (nmap == 0 && count > 1) {
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);
if ((error = xfs_bmapi(tp, dp, b, c,
xfs_bmapi_aflag(w)|XFS_BMAPI_WRITE|
XFS_BMAPI_METADATA,
args->firstblock, args->total,
&mapp[mapi], &nmap, args->flist))) {
kmem_free(mapp);
return error;
}
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) {
if (mapp != &map)
kmem_free(mapp);
return XFS_ERROR(ENOSPC);
}
if (mapp != &map)
kmem_free(mapp);
/* account for newly allocated blocks in reserved blocks total */
args->total -= dp->i_d.di_nblocks - nblks;
*new_blkno = (xfs_dablk_t)bno;
return 0;
}
/*
* 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_da_swap_lastblock(xfs_da_args_t *args, xfs_dablk_t *dead_blknop,
xfs_dabuf_t **dead_bufp)
{
xfs_dablk_t dead_blkno, last_blkno, sib_blkno, par_blkno;
xfs_dabuf_t *dead_buf, *last_buf, *sib_buf, *par_buf;
xfs_fileoff_t lastoff;
xfs_inode_t *ip;
xfs_trans_t *tp;
xfs_mount_t *mp;
int error, w, entno, level, dead_level;
xfs_da_blkinfo_t *dead_info, *sib_info;
xfs_da_intnode_t *par_node, *dead_node;
xfs_dir2_leaf_t *dead_leaf2;
xfs_dahash_t dead_hash;
dead_buf = *dead_bufp;
dead_blkno = *dead_blknop;
tp = args->trans;
ip = args->dp;
w = args->whichfork;
ASSERT(w == XFS_DATA_FORK);
mp = ip->i_mount;
lastoff = mp->m_dirfreeblk;
error = xfs_bmap_last_before(tp, ip, &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;
if ((error = xfs_da_read_buf(tp, ip, last_blkno, -1, &last_buf, w)))
return error;
/*
* Copy the last block into the dead buffer and log it.
*/
memcpy(dead_buf->data, last_buf->data, mp->m_dirblksize);
xfs_da_log_buf(tp, dead_buf, 0, mp->m_dirblksize - 1);
dead_info = dead_buf->data;
/*
* Get values from the moved block.
*/
if (be16_to_cpu(dead_info->magic) == XFS_DIR2_LEAFN_MAGIC) {
dead_leaf2 = (xfs_dir2_leaf_t *)dead_info;
dead_level = 0;
dead_hash = be32_to_cpu(dead_leaf2->ents[be16_to_cpu(dead_leaf2->hdr.count) - 1].hashval);
} else {
ASSERT(be16_to_cpu(dead_info->magic) == XFS_DA_NODE_MAGIC);
dead_node = (xfs_da_intnode_t *)dead_info;
dead_level = be16_to_cpu(dead_node->hdr.level);
dead_hash = be32_to_cpu(dead_node->btree[be16_to_cpu(dead_node->hdr.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))) {
if ((error = xfs_da_read_buf(tp, ip, sib_blkno, -1, &sib_buf, w)))
goto done;
sib_info = sib_buf->data;
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_da_log_buf(tp, sib_buf,
XFS_DA_LOGRANGE(sib_info, &sib_info->forw,
sizeof(sib_info->forw)));
xfs_da_buf_done(sib_buf);
sib_buf = NULL;
}
/*
* If the moved block has a right sibling, fix up the pointers.
*/
if ((sib_blkno = be32_to_cpu(dead_info->forw))) {
if ((error = xfs_da_read_buf(tp, ip, sib_blkno, -1, &sib_buf, w)))
goto done;
sib_info = sib_buf->data;
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_da_log_buf(tp, sib_buf,
XFS_DA_LOGRANGE(sib_info, &sib_info->back,
sizeof(sib_info->back)));
xfs_da_buf_done(sib_buf);
sib_buf = NULL;
}
par_blkno = mp->m_dirleafblk;
level = -1;
/*
* Walk down the tree looking for the parent of the moved block.
*/
for (;;) {
if ((error = xfs_da_read_buf(tp, ip, par_blkno, -1, &par_buf, w)))
goto done;
par_node = par_buf->data;
if (unlikely(
be16_to_cpu(par_node->hdr.info.magic) != XFS_DA_NODE_MAGIC ||
(level >= 0 && level != be16_to_cpu(par_node->hdr.level) + 1))) {
XFS_ERROR_REPORT("xfs_da_swap_lastblock(4)",
XFS_ERRLEVEL_LOW, mp);
error = XFS_ERROR(EFSCORRUPTED);
goto done;
}
level = be16_to_cpu(par_node->hdr.level);
for (entno = 0;
entno < be16_to_cpu(par_node->hdr.count) &&
be32_to_cpu(par_node->btree[entno].hashval) < dead_hash;
entno++)
continue;
if (unlikely(entno == be16_to_cpu(par_node->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(par_node->btree[entno].before);
if (level == dead_level + 1)
break;
xfs_da_brelse(tp, par_buf);
par_buf = NULL;
}
/*
* We're in the right parent block.
* Look for the right entry.
*/
for (;;) {
for (;
entno < be16_to_cpu(par_node->hdr.count) &&
be32_to_cpu(par_node->btree[entno].before) != last_blkno;
entno++)
continue;
if (entno < be16_to_cpu(par_node->hdr.count))
break;
par_blkno = be32_to_cpu(par_node->hdr.info.forw);
xfs_da_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;
}
if ((error = xfs_da_read_buf(tp, ip, par_blkno, -1, &par_buf, w)))
goto done;
par_node = par_buf->data;
if (unlikely(
be16_to_cpu(par_node->hdr.level) != level ||
be16_to_cpu(par_node->hdr.info.magic) != XFS_DA_NODE_MAGIC)) {
XFS_ERROR_REPORT("xfs_da_swap_lastblock(7)",
XFS_ERRLEVEL_LOW, mp);
error = XFS_ERROR(EFSCORRUPTED);
goto done;
}
entno = 0;
}
/*
* Update the parent entry pointing to the moved block.
*/
par_node->btree[entno].before = cpu_to_be32(dead_blkno);
xfs_da_log_buf(tp, par_buf,
XFS_DA_LOGRANGE(par_node, &par_node->btree[entno].before,
sizeof(par_node->btree[entno].before)));
xfs_da_buf_done(par_buf);
xfs_da_buf_done(dead_buf);
*dead_blknop = last_blkno;
*dead_bufp = last_buf;
return 0;
done:
if (par_buf)
xfs_da_brelse(tp, par_buf);
if (sib_buf)
xfs_da_brelse(tp, sib_buf);
xfs_da_brelse(tp, last_buf);
return error;
}
/*
* Remove a btree block from a directory or attribute.
*/
int
xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno,
xfs_dabuf_t *dead_buf)
{
xfs_inode_t *dp;
int done, error, w, count;
xfs_trans_t *tp;
xfs_mount_t *mp;
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.
*/
if ((error = xfs_bunmapi(tp, dp, dead_blkno, count,
xfs_bmapi_aflag(w)|XFS_BMAPI_METADATA,
0, args->firstblock, args->flist,
&done)) == ENOSPC) {
if (w != XFS_DATA_FORK)
break;
if ((error = xfs_da_swap_lastblock(args, &dead_blkno,
&dead_buf)))
break;
} else {
break;
}
}
xfs_da_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;
}
/*
* Make a dabuf.
* Used for get_buf, read_buf, read_bufr, and reada_buf.
*/
STATIC int
xfs_da_do_buf(
xfs_trans_t *trans,
xfs_inode_t *dp,
xfs_dablk_t bno,
xfs_daddr_t *mappedbnop,
xfs_dabuf_t **bpp,
int whichfork,
int caller,
inst_t *ra)
{
xfs_buf_t *bp = NULL;
xfs_buf_t **bplist;
int error=0;
int i;
xfs_bmbt_irec_t map;
xfs_bmbt_irec_t *mapp;
xfs_daddr_t mappedbno;
xfs_mount_t *mp;
int nbplist=0;
int nfsb;
int nmap;
xfs_dabuf_t *rbp;
mp = dp->i_mount;
nfsb = (whichfork == XFS_DATA_FORK) ? mp->m_dirblkfsbs : 1;
mappedbno = *mappedbnop;
/*
* 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) {
xfs_fsblock_t fsb;
if ((error =
xfs_bmapi_single(trans, dp, whichfork, &fsb,
(xfs_fileoff_t)bno))) {
return error;
}
mapp = &map;
if (fsb == NULLFSBLOCK) {
nmap = 0;
} else {
map.br_startblock = fsb;
map.br_startoff = (xfs_fileoff_t)bno;
map.br_blockcount = 1;
nmap = 1;
}
} else {
mapp = kmem_alloc(sizeof(*mapp) * nfsb, KM_SLEEP);
nmap = nfsb;
if ((error = xfs_bmapi(trans, dp, (xfs_fileoff_t)bno,
nfsb,
XFS_BMAPI_METADATA |
xfs_bmapi_aflag(whichfork),
NULL, 0, mapp, &nmap, NULL)))
goto exit0;
}
} else {
map.br_startblock = XFS_DADDR_TO_FSB(mp, mappedbno);
map.br_startoff = (xfs_fileoff_t)bno;
map.br_blockcount = nfsb;
mapp = &map;
nmap = 1;
}
if (!xfs_da_map_covers_blocks(nmap, mapp, bno, nfsb)) {
error = mappedbno == -2 ? 0 : XFS_ERROR(EFSCORRUPTED);
if (unlikely(error == EFSCORRUPTED)) {
if (xfs_error_level >= XFS_ERRLEVEL_LOW) {
cmn_err(CE_ALERT, "xfs_da_do_buf: bno %lld\n",
(long long)bno);
cmn_err(CE_ALERT, "dir: inode %lld\n",
(long long)dp->i_ino);
for (i = 0; i < nmap; i++) {
cmn_err(CE_ALERT,
"[%02d] br_startoff %lld br_startblock %lld br_blockcount %lld br_state %d\n",
i,
(long long)mapp[i].br_startoff,
(long long)mapp[i].br_startblock,
(long long)mapp[i].br_blockcount,
mapp[i].br_state);
}
}
XFS_ERROR_REPORT("xfs_da_do_buf(1)",
XFS_ERRLEVEL_LOW, mp);
}
goto exit0;
}
if (caller != 3 && nmap > 1) {
bplist = kmem_alloc(sizeof(*bplist) * nmap, KM_SLEEP);
nbplist = 0;
} else
bplist = NULL;
/*
* Turn the mapping(s) into buffer(s).
*/
for (i = 0; i < nmap; i++) {
int nmapped;
mappedbno = XFS_FSB_TO_DADDR(mp, mapp[i].br_startblock);
if (i == 0)
*mappedbnop = mappedbno;
nmapped = (int)XFS_FSB_TO_BB(mp, mapp[i].br_blockcount);
switch (caller) {
case 0:
bp = xfs_trans_get_buf(trans, mp->m_ddev_targp,
mappedbno, nmapped, 0);
error = bp ? XFS_BUF_GETERROR(bp) : XFS_ERROR(EIO);
break;
case 1:
case 2:
bp = NULL;
error = xfs_trans_read_buf(mp, trans, mp->m_ddev_targp,
mappedbno, nmapped, 0, &bp);
break;
case 3:
xfs_baread(mp->m_ddev_targp, mappedbno, nmapped);
error = 0;
bp = NULL;
break;
}
if (error) {
if (bp)
xfs_trans_brelse(trans, bp);
goto exit1;
}
if (!bp)
continue;
if (caller == 1) {
if (whichfork == XFS_ATTR_FORK) {
XFS_BUF_SET_VTYPE_REF(bp, B_FS_ATTR_BTREE,
XFS_ATTR_BTREE_REF);
} else {
XFS_BUF_SET_VTYPE_REF(bp, B_FS_DIR_BTREE,
XFS_DIR_BTREE_REF);
}
}
if (bplist) {
bplist[nbplist++] = bp;
}
}
/*
* Build a dabuf structure.
*/
if (bplist) {
rbp = xfs_da_buf_make(nbplist, bplist, ra);
} else if (bp)
rbp = xfs_da_buf_make(1, &bp, ra);
else
rbp = NULL;
/*
* For read_buf, check the magic number.
*/
if (caller == 1) {
xfs_dir2_data_t *data;
xfs_dir2_free_t *free;
xfs_da_blkinfo_t *info;
uint magic, magic1;
info = rbp->data;
data = rbp->data;
free = rbp->data;
magic = be16_to_cpu(info->magic);
magic1 = be32_to_cpu(data->hdr.magic);
if (unlikely(
XFS_TEST_ERROR((magic != XFS_DA_NODE_MAGIC) &&
(magic != XFS_ATTR_LEAF_MAGIC) &&
(magic != XFS_DIR2_LEAF1_MAGIC) &&
(magic != XFS_DIR2_LEAFN_MAGIC) &&
(magic1 != XFS_DIR2_BLOCK_MAGIC) &&
(magic1 != XFS_DIR2_DATA_MAGIC) &&
(be32_to_cpu(free->hdr.magic) != XFS_DIR2_FREE_MAGIC),
mp, XFS_ERRTAG_DA_READ_BUF,
XFS_RANDOM_DA_READ_BUF))) {
trace_xfs_da_btree_corrupt(rbp->bps[0], _RET_IP_);
XFS_CORRUPTION_ERROR("xfs_da_do_buf(2)",
XFS_ERRLEVEL_LOW, mp, info);
error = XFS_ERROR(EFSCORRUPTED);
xfs_da_brelse(trans, rbp);
nbplist = 0;
goto exit1;
}
}
if (bplist) {
kmem_free(bplist);
}
if (mapp != &map) {
kmem_free(mapp);
}
if (bpp)
*bpp = rbp;
return 0;
exit1:
if (bplist) {
for (i = 0; i < nbplist; i++)
xfs_trans_brelse(trans, bplist[i]);
kmem_free(bplist);
}
exit0:
if (mapp != &map)
kmem_free(mapp);
if (bpp)
*bpp = NULL;
return error;
}
/*
* Get a buffer for the dir/attr block.
*/
int
xfs_da_get_buf(
xfs_trans_t *trans,
xfs_inode_t *dp,
xfs_dablk_t bno,
xfs_daddr_t mappedbno,
xfs_dabuf_t **bpp,
int whichfork)
{
return xfs_da_do_buf(trans, dp, bno, &mappedbno, bpp, whichfork, 0,
(inst_t *)__return_address);
}
/*
* Get a buffer for the dir/attr block, fill in the contents.
*/
int
xfs_da_read_buf(
xfs_trans_t *trans,
xfs_inode_t *dp,
xfs_dablk_t bno,
xfs_daddr_t mappedbno,
xfs_dabuf_t **bpp,
int whichfork)
{
return xfs_da_do_buf(trans, dp, bno, &mappedbno, bpp, whichfork, 1,
(inst_t *)__return_address);
}
/*
* Readahead the dir/attr block.
*/
xfs_daddr_t
xfs_da_reada_buf(
xfs_trans_t *trans,
xfs_inode_t *dp,
xfs_dablk_t bno,
int whichfork)
{
xfs_daddr_t rval;
rval = -1;
if (xfs_da_do_buf(trans, dp, bno, &rval, NULL, whichfork, 3,
(inst_t *)__return_address))
return -1;
else
return rval;
}
kmem_zone_t *xfs_da_state_zone; /* anchor for state struct zone */
kmem_zone_t *xfs_dabuf_zone; /* dabuf 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++) {
if (state->altpath.blk[i].bp) {
if (state->altpath.blk[i].bp != state->path.blk[i].bp)
xfs_da_buf_done(state->altpath.blk[i].bp);
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)
{
int i;
xfs_da_state_kill_altpath(state);
for (i = 0; i < state->path.active; i++) {
if (state->path.blk[i].bp)
xfs_da_buf_done(state->path.blk[i].bp);
}
if (state->extravalid && state->extrablk.bp)
xfs_da_buf_done(state->extrablk.bp);
#ifdef DEBUG
memset((char *)state, 0, sizeof(*state));
#endif /* DEBUG */
kmem_zone_free(xfs_da_state_zone, state);
}
#ifdef XFS_DABUF_DEBUG
xfs_dabuf_t *xfs_dabuf_global_list;
static DEFINE_SPINLOCK(xfs_dabuf_global_lock);
#endif
/*
* Create a dabuf.
*/
/* ARGSUSED */
STATIC xfs_dabuf_t *
xfs_da_buf_make(int nbuf, xfs_buf_t **bps, inst_t *ra)
{
xfs_buf_t *bp;
xfs_dabuf_t *dabuf;
int i;
int off;
if (nbuf == 1)
dabuf = kmem_zone_alloc(xfs_dabuf_zone, KM_NOFS);
else
dabuf = kmem_alloc(XFS_DA_BUF_SIZE(nbuf), KM_NOFS);
dabuf->dirty = 0;
#ifdef XFS_DABUF_DEBUG
dabuf->ra = ra;
dabuf->target = XFS_BUF_TARGET(bps[0]);
dabuf->blkno = XFS_BUF_ADDR(bps[0]);
#endif
if (nbuf == 1) {
dabuf->nbuf = 1;
bp = bps[0];
dabuf->bbcount = (short)BTOBB(XFS_BUF_COUNT(bp));
dabuf->data = XFS_BUF_PTR(bp);
dabuf->bps[0] = bp;
} else {
dabuf->nbuf = nbuf;
for (i = 0, dabuf->bbcount = 0; i < nbuf; i++) {
dabuf->bps[i] = bp = bps[i];
dabuf->bbcount += BTOBB(XFS_BUF_COUNT(bp));
}
dabuf->data = kmem_alloc(BBTOB(dabuf->bbcount), KM_SLEEP);
for (i = off = 0; i < nbuf; i++, off += XFS_BUF_COUNT(bp)) {
bp = bps[i];
memcpy((char *)dabuf->data + off, XFS_BUF_PTR(bp),
XFS_BUF_COUNT(bp));
}
}
#ifdef XFS_DABUF_DEBUG
{
xfs_dabuf_t *p;
spin_lock(&xfs_dabuf_global_lock);
for (p = xfs_dabuf_global_list; p; p = p->next) {
ASSERT(p->blkno != dabuf->blkno ||
p->target != dabuf->target);
}
dabuf->prev = NULL;
if (xfs_dabuf_global_list)
xfs_dabuf_global_list->prev = dabuf;
dabuf->next = xfs_dabuf_global_list;
xfs_dabuf_global_list = dabuf;
spin_unlock(&xfs_dabuf_global_lock);
}
#endif
return dabuf;
}
/*
* Un-dirty a dabuf.
*/
STATIC void
xfs_da_buf_clean(xfs_dabuf_t *dabuf)
{
xfs_buf_t *bp;
int i;
int off;
if (dabuf->dirty) {
ASSERT(dabuf->nbuf > 1);
dabuf->dirty = 0;
for (i = off = 0; i < dabuf->nbuf;
i++, off += XFS_BUF_COUNT(bp)) {
bp = dabuf->bps[i];
memcpy(XFS_BUF_PTR(bp), (char *)dabuf->data + off,
XFS_BUF_COUNT(bp));
}
}
}
/*
* Release a dabuf.
*/
void
xfs_da_buf_done(xfs_dabuf_t *dabuf)
{
ASSERT(dabuf);
ASSERT(dabuf->nbuf && dabuf->data && dabuf->bbcount && dabuf->bps[0]);
if (dabuf->dirty)
xfs_da_buf_clean(dabuf);
if (dabuf->nbuf > 1)
kmem_free(dabuf->data);
#ifdef XFS_DABUF_DEBUG
{
spin_lock(&xfs_dabuf_global_lock);
if (dabuf->prev)
dabuf->prev->next = dabuf->next;
else
xfs_dabuf_global_list = dabuf->next;
if (dabuf->next)
dabuf->next->prev = dabuf->prev;
spin_unlock(&xfs_dabuf_global_lock);
}
memset(dabuf, 0, XFS_DA_BUF_SIZE(dabuf->nbuf));
#endif
if (dabuf->nbuf == 1)
kmem_zone_free(xfs_dabuf_zone, dabuf);
else
kmem_free(dabuf);
}
/*
* Log transaction from a dabuf.
*/
void
xfs_da_log_buf(xfs_trans_t *tp, xfs_dabuf_t *dabuf, uint first, uint last)
{
xfs_buf_t *bp;
uint f;
int i;
uint l;
int off;
ASSERT(dabuf->nbuf && dabuf->data && dabuf->bbcount && dabuf->bps[0]);
if (dabuf->nbuf == 1) {
ASSERT(dabuf->data == (void *)XFS_BUF_PTR(dabuf->bps[0]));
xfs_trans_log_buf(tp, dabuf->bps[0], first, last);
return;
}
dabuf->dirty = 1;
ASSERT(first <= last);
for (i = off = 0; i < dabuf->nbuf; i++, off += XFS_BUF_COUNT(bp)) {
bp = dabuf->bps[i];
f = off;
l = f + XFS_BUF_COUNT(bp) - 1;
if (f < first)
f = first;
if (l > last)
l = last;
if (f <= l)
xfs_trans_log_buf(tp, bp, f - off, l - off);
/*
* B_DONE is set by xfs_trans_log buf.
* If we don't set it on a new buffer (get not read)
* then if we don't put anything in the buffer it won't
* be set, and at commit it it released into the cache,
* and then a read will fail.
*/
else if (!(XFS_BUF_ISDONE(bp)))
XFS_BUF_DONE(bp);
}
ASSERT(last < off);
}
/*
* Release dabuf from a transaction.
* Have to free up the dabuf before the buffers are released,
* since the synchronization on the dabuf is really the lock on the buffer.
*/
void
xfs_da_brelse(xfs_trans_t *tp, xfs_dabuf_t *dabuf)
{
xfs_buf_t *bp;
xfs_buf_t **bplist;
int i;
int nbuf;
ASSERT(dabuf->nbuf && dabuf->data && dabuf->bbcount && dabuf->bps[0]);
if ((nbuf = dabuf->nbuf) == 1) {
bplist = &bp;
bp = dabuf->bps[0];
} else {
bplist = kmem_alloc(nbuf * sizeof(*bplist), KM_SLEEP);
memcpy(bplist, dabuf->bps, nbuf * sizeof(*bplist));
}
xfs_da_buf_done(dabuf);
for (i = 0; i < nbuf; i++)
xfs_trans_brelse(tp, bplist[i]);
if (bplist != &bp)
kmem_free(bplist);
}
/*
* Invalidate dabuf from a transaction.
*/
void
xfs_da_binval(xfs_trans_t *tp, xfs_dabuf_t *dabuf)
{
xfs_buf_t *bp;
xfs_buf_t **bplist;
int i;
int nbuf;
ASSERT(dabuf->nbuf && dabuf->data && dabuf->bbcount && dabuf->bps[0]);
if ((nbuf = dabuf->nbuf) == 1) {
bplist = &bp;
bp = dabuf->bps[0];
} else {
bplist = kmem_alloc(nbuf * sizeof(*bplist), KM_SLEEP);
memcpy(bplist, dabuf->bps, nbuf * sizeof(*bplist));
}
xfs_da_buf_done(dabuf);
for (i = 0; i < nbuf; i++)
xfs_trans_binval(tp, bplist[i]);
if (bplist != &bp)
kmem_free(bplist);
}
/*
* Get the first daddr from a dabuf.
*/
xfs_daddr_t
xfs_da_blkno(xfs_dabuf_t *dabuf)
{
ASSERT(dabuf->nbuf);
ASSERT(dabuf->data);
return XFS_BUF_ADDR(dabuf->bps[0]);
}
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