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/*
* Copyright (c) 2000 Silicon Graphics, Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 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.
*
* Further, this software is distributed without any warranty that it is
* free of the rightful claim of any third person regarding infringement
* or the like. Any license provided herein, whether implied or
* otherwise, applies only to this software file. Patent licenses, if
* any, provided herein do not apply to combinations of this program with
* other software, or any other product whatsoever.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write the Free Software Foundation, Inc., 59
* Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
* Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
* Mountain View, CA 94043, or:
*
* http://www.sgi.com
*
* For further information regarding this notice, see:
*
* http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
*/
#include <xfs.h>
#if defined(XFSDEBUG) && defined(CONFIG_KDB)
#undef xfs_buftrace
#define xfs_buftrace(A,B) panic(" xfs_buftrace : %s (0x%p)\n", A, B);
#endif
/*
* 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);
/*========================================================================
* 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;
INT_ZERO(node->hdr.info.forw, ARCH_CONVERT);
INT_ZERO(node->hdr.info.back, ARCH_CONVERT);
INT_SET(node->hdr.info.magic, ARCH_CONVERT, XFS_DA_NODE_MAGIC);
INT_ZERO(node->hdr.info.pad, ARCH_CONVERT);
INT_ZERO(node->hdr.count, ARCH_CONVERT);
INT_SET(node->hdr.level, ARCH_CONVERT, 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_DIRX_LEAF_MAGIC(state->mp));
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:
#ifndef __KERNEL__
return(ENOTTY);
#else
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;
#endif
case XFS_DIR_LEAF_MAGIC:
ASSERT(XFS_DIR_IS_V1(state->mp));
error = xfs_dir_leaf_split(state, oldblk, newblk);
if ((error != 0) && (error != ENOSPC)) {
return(error); /* GROT: dir 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_dir_leaf_split(state, oldblk,
&state->extrablk);
if (error)
return(error); /* GROT: dir incon. */
addblk = newblk;
} else {
state->extraafter = 1; /* after newblk */
error = xfs_dir_leaf_split(state, newblk,
&state->extrablk);
if (error)
return(error); /* GROT: dir incon. */
addblk = newblk;
}
break;
case XFS_DIR2_LEAFN_MAGIC:
ASSERT(XFS_DIR_IS_V2(state->mp));
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 (!INT_ISZERO(node->hdr.info.forw, ARCH_CONVERT)) {
if (INT_GET(node->hdr.info.forw, ARCH_CONVERT) == addblk->blkno) {
bp = addblk->bp;
} else {
ASSERT(state->extravalid);
bp = state->extrablk.bp;
}
node = bp->data;
INT_SET(node->hdr.info.back, ARCH_CONVERT, 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 (INT_GET(node->hdr.info.back, ARCH_CONVERT)) {
if (INT_GET(node->hdr.info.back, ARCH_CONVERT) == addblk->blkno) {
bp = addblk->bp;
} else {
ASSERT(state->extravalid);
bp = state->extrablk.bp;
}
node = bp->data;
INT_SET(node->hdr.info.forw, ARCH_CONVERT, 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 (INT_GET(oldroot->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC) {
size = (int)((char *)&oldroot->btree[INT_GET(oldroot->hdr.count, ARCH_CONVERT)] -
(char *)oldroot);
} else {
ASSERT(XFS_DIR_IS_V2(mp));
ASSERT(INT_GET(oldroot->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
leaf = (xfs_dir2_leaf_t *)oldroot;
size = (int)((char *)&leaf->ents[INT_GET(leaf->hdr.count, ARCH_CONVERT)] -
(char *)leaf);
}
bcopy(oldroot, node, 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 &&
XFS_DIR_IS_V2(mp) ? mp->m_dirleafblk : 0,
INT_GET(node->hdr.level, ARCH_CONVERT) + 1, &bp, args->whichfork);
if (error)
return(error);
node = bp->data;
INT_SET(node->btree[0].hashval, ARCH_CONVERT, blk1->hashval);
INT_SET(node->btree[0].before, ARCH_CONVERT, blk1->blkno);
INT_SET(node->btree[1].hashval, ARCH_CONVERT, blk2->hashval);
INT_SET(node->btree[1].before, ARCH_CONVERT, blk2->blkno);
INT_SET(node->hdr.count, ARCH_CONVERT, 2);
if (XFS_DIR_IS_V2(mp)) {
ASSERT(blk1->blkno >= mp->m_dirleafblk &&
blk1->blkno < mp->m_dirfreeblk);
ASSERT(blk2->blkno >= mp->m_dirleafblk &&
blk2->blkno < mp->m_dirfreeblk);
}
/* 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(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
/*
* With V2 the extra block is data or freespace.
*/
useextra = state->extravalid && XFS_DIR_IS_V1(state->mp);
newcount = 1 + useextra;
/*
* Do we have to split the node?
*/
if ((INT_GET(node->hdr.count, ARCH_CONVERT) + newcount) > XFS_DA_NODE_ENTRIES(state->mp)) {
/*
* 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 <= INT_GET(node->hdr.count, ARCH_CONVERT)) {
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 ((INT_GET(node1->hdr.count, ARCH_CONVERT) > 0) && (INT_GET(node2->hdr.count, ARCH_CONVERT) > 0) &&
((INT_GET(node2->btree[ 0 ].hashval, ARCH_CONVERT) < INT_GET(node1->btree[ 0 ].hashval, ARCH_CONVERT)) ||
(INT_GET(node2->btree[ INT_GET(node2->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT) <
INT_GET(node1->btree[ INT_GET(node1->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT)))) {
tmpnode = node1;
node1 = node2;
node2 = tmpnode;
}
ASSERT(INT_GET(node1->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
ASSERT(INT_GET(node2->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
count = (INT_GET(node1->hdr.count, ARCH_CONVERT) - INT_GET(node2->hdr.count, ARCH_CONVERT)) / 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 = INT_GET(node2->hdr.count, ARCH_CONVERT)) > 0) {
tmp *= (uint)sizeof(xfs_da_node_entry_t);
btree_s = &node2->btree[0];
btree_d = &node2->btree[count];
ovbcopy(btree_s, btree_d, tmp);
}
/*
* Move the req'd B-tree elements from high in node1 to
* low in node2.
*/
INT_MOD(node2->hdr.count, ARCH_CONVERT, count);
tmp = count * (uint)sizeof(xfs_da_node_entry_t);
btree_s = &node1->btree[INT_GET(node1->hdr.count, ARCH_CONVERT) - count];
btree_d = &node2->btree[0];
bcopy(btree_s, btree_d, tmp);
INT_MOD(node1->hdr.count, ARCH_CONVERT, -(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[INT_GET(node1->hdr.count, ARCH_CONVERT)];
bcopy(btree_s, btree_d, tmp);
INT_MOD(node1->hdr.count, ARCH_CONVERT, 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 = INT_GET(node2->hdr.count, ARCH_CONVERT) - count;
tmp *= (uint)sizeof(xfs_da_node_entry_t);
btree_s = &node2->btree[count];
btree_d = &node2->btree[0];
ovbcopy(btree_s, btree_d, tmp);
INT_MOD(node2->hdr.count, ARCH_CONVERT, -(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]) * INT_GET(node2->hdr.count, ARCH_CONVERT)));
/*
* 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 = INT_GET(node1->btree[ INT_GET(node1->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
blk2->hashval = INT_GET(node2->btree[ INT_GET(node2->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
/*
* Adjust the expected index for insertion.
*/
if (blk1->index >= INT_GET(node1->hdr.count, ARCH_CONVERT)) {
blk2->index = blk1->index - INT_GET(node1->hdr.count, ARCH_CONVERT);
blk1->index = INT_GET(node1->hdr.count, ARCH_CONVERT) + 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(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
ASSERT((oldblk->index >= 0) && (oldblk->index <= INT_GET(node->hdr.count, ARCH_CONVERT)));
ASSERT(newblk->blkno != 0);
if (state->args->whichfork == XFS_DATA_FORK && XFS_DIR_IS_V2(mp))
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 < INT_GET(node->hdr.count, ARCH_CONVERT)) {
tmp = (INT_GET(node->hdr.count, ARCH_CONVERT) - oldblk->index) * (uint)sizeof(*btree);
ovbcopy(btree, btree + 1, tmp);
}
INT_SET(btree->hashval, ARCH_CONVERT, newblk->hashval);
INT_SET(btree->before, ARCH_CONVERT, newblk->blkno);
xfs_da_log_buf(state->args->trans, oldblk->bp,
XFS_DA_LOGRANGE(node, btree, tmp + sizeof(*btree)));
INT_MOD(node->hdr.count, ARCH_CONVERT, +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 = INT_GET(node->btree[ INT_GET(node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
}
/*========================================================================
* 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_DIRX_LEAF_MAGIC(state->mp));
/*
* 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:
#ifndef __KERNEL__
error = ENOTTY;
#else
error = xfs_attr_leaf_toosmall(state, &action);
#endif
if (error)
return(error);
if (action == 0)
return(0);
#ifdef __KERNEL__
xfs_attr_leaf_unbalance(state, drop_blk, save_blk);
#endif
break;
case XFS_DIR_LEAF_MAGIC:
ASSERT(XFS_DIR_IS_V1(state->mp));
error = xfs_dir_leaf_toosmall(state, &action);
if (error)
return(error);
if (action == 0)
return(0);
xfs_dir_leaf_unbalance(state, drop_blk, save_blk);
break;
case XFS_DIR2_LEAFN_MAGIC:
ASSERT(XFS_DIR_IS_V2(state->mp));
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(INT_GET(oldroot->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
ASSERT(INT_ISZERO(oldroot->hdr.info.forw, ARCH_CONVERT));
ASSERT(INT_ISZERO(oldroot->hdr.info.back, ARCH_CONVERT));
/*
* If the root has more than one child, then don't do anything.
*/
if (INT_GET(oldroot->hdr.count, ARCH_CONVERT) > 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 = INT_GET(oldroot->btree[ 0 ].before, ARCH_CONVERT);
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 (INT_GET(oldroot->hdr.level, ARCH_CONVERT) == 1) {
ASSERT(INT_GET(blkinfo->magic, ARCH_CONVERT) == XFS_DIRX_LEAF_MAGIC(state->mp) ||
INT_GET(blkinfo->magic, ARCH_CONVERT) == XFS_ATTR_LEAF_MAGIC);
} else {
ASSERT(INT_GET(blkinfo->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
}
ASSERT(INT_GET(blkinfo->forw, ARCH_CONVERT) == 0);
ASSERT(INT_GET(blkinfo->back, ARCH_CONVERT) == 0);
bcopy(bp->data, root_blk->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(INT_GET(info->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
node = (xfs_da_intnode_t *)info;
count = INT_GET(node->hdr.count, ARCH_CONVERT);
if (count > (XFS_DA_NODE_ENTRIES(state->mp) >> 1)) {
*action = 0; /* blk over 50%, dont try to join */
return(0); /* blk over 50%, dont 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 (aribtrarily)
* 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 = (!INT_ISZERO(info->forw, ARCH_CONVERT));
bcopy(&state->path, &state->altpath, 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 = (INT_GET(info->forw, ARCH_CONVERT)
< INT_GET(info->back, ARCH_CONVERT));
for (i = 0; i < 2; forward = !forward, i++) {
if (forward)
blkno = INT_GET(info->forw, ARCH_CONVERT);
else
blkno = INT_GET(info->back, ARCH_CONVERT);
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 = XFS_DA_NODE_ENTRIES(state->mp);
count -= XFS_DA_NODE_ENTRIES(state->mp) >> 2;
count -= INT_GET(node->hdr.count, ARCH_CONVERT);
node = bp->data;
ASSERT(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
count -= INT_GET(node->hdr.count, ARCH_CONVERT);
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.
*/
bcopy(&state->path, &state->altpath, 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) {
#ifdef __KERNEL__
case XFS_ATTR_LEAF_MAGIC:
lasthash = xfs_attr_leaf_lasthash(blk->bp, &count);
if (count == 0)
return;
break;
#endif
case XFS_DIR_LEAF_MAGIC:
ASSERT(XFS_DIR_IS_V1(state->mp));
lasthash = xfs_dir_leaf_lasthash(blk->bp, &count);
if (count == 0)
return;
break;
case XFS_DIR2_LEAFN_MAGIC:
ASSERT(XFS_DIR_IS_V2(state->mp));
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(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
btree = &node->btree[ blk->index ];
if (INT_GET(btree->hashval, ARCH_CONVERT) == lasthash)
break;
blk->hashval = lasthash;
INT_SET(btree->hashval, ARCH_CONVERT, lasthash);
xfs_da_log_buf(state->args->trans, blk->bp,
XFS_DA_LOGRANGE(node, btree, sizeof(*btree)));
lasthash = INT_GET(node->btree[ INT_GET(node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
}
}
/*
* 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 < INT_GET(node->hdr.count, ARCH_CONVERT));
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 < (INT_GET(node->hdr.count, ARCH_CONVERT)-1)) {
tmp = INT_GET(node->hdr.count, ARCH_CONVERT) - drop_blk->index - 1;
tmp *= (uint)sizeof(xfs_da_node_entry_t);
ovbcopy(btree + 1, btree, tmp);
xfs_da_log_buf(state->args->trans, drop_blk->bp,
XFS_DA_LOGRANGE(node, btree, tmp));
btree = &node->btree[ INT_GET(node->hdr.count, ARCH_CONVERT)-1 ];
}
bzero((char *)btree, sizeof(xfs_da_node_entry_t));
xfs_da_log_buf(state->args->trans, drop_blk->bp,
XFS_DA_LOGRANGE(node, btree, sizeof(*btree)));
INT_MOD(node->hdr.count, ARCH_CONVERT, -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 = INT_GET(btree->hashval, ARCH_CONVERT);
}
/*
* 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(INT_GET(drop_node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
ASSERT(INT_GET(save_node->hdr.info.magic, ARCH_CONVERT) == 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 ((INT_GET(drop_node->btree[ 0 ].hashval, ARCH_CONVERT) < INT_GET(save_node->btree[ 0 ].hashval, ARCH_CONVERT)) ||
(INT_GET(drop_node->btree[ INT_GET(drop_node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT) <
INT_GET(save_node->btree[ INT_GET(save_node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT)))
{
btree = &save_node->btree[ INT_GET(drop_node->hdr.count, ARCH_CONVERT) ];
tmp = INT_GET(save_node->hdr.count, ARCH_CONVERT) * (uint)sizeof(xfs_da_node_entry_t);
ovbcopy(&save_node->btree[0], btree, tmp);
btree = &save_node->btree[0];
xfs_da_log_buf(tp, save_blk->bp,
XFS_DA_LOGRANGE(save_node, btree,
(INT_GET(save_node->hdr.count, ARCH_CONVERT) + INT_GET(drop_node->hdr.count, ARCH_CONVERT)) *
sizeof(xfs_da_node_entry_t)));
} else {
btree = &save_node->btree[ INT_GET(save_node->hdr.count, ARCH_CONVERT) ];
xfs_da_log_buf(tp, save_blk->bp,
XFS_DA_LOGRANGE(save_node, btree,
INT_GET(drop_node->hdr.count, ARCH_CONVERT) *
sizeof(xfs_da_node_entry_t)));
}
/*
* Move all the B-tree elements from drop_blk to save_blk.
*/
tmp = INT_GET(drop_node->hdr.count, ARCH_CONVERT) * (uint)sizeof(xfs_da_node_entry_t);
bcopy(&drop_node->btree[0], btree, tmp);
INT_MOD(save_node->hdr.count, ARCH_CONVERT, INT_GET(drop_node->hdr.count, ARCH_CONVERT));
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 = INT_GET(save_node->btree[ INT_GET(save_node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
}
/*========================================================================
* 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;
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.
*/
if (args->whichfork == XFS_DATA_FORK && XFS_DIR_IS_V2(state->mp))
blkno = state->mp->m_dirleafblk;
else
blkno = 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(state->args->trans, state->args->dp,
blkno, -1, &blk->bp,
state->args->whichfork);
if (error) {
blk->blkno = 0;
state->path.active--;
return(error);
}
ASSERT(blk->bp != NULL);
curr = blk->bp->data;
ASSERT(INT_GET(curr->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC ||
INT_GET(curr->magic, ARCH_CONVERT) == XFS_DIRX_LEAF_MAGIC(state->mp) ||
INT_GET(curr->magic, ARCH_CONVERT) == XFS_ATTR_LEAF_MAGIC);
/*
* Search an intermediate node for a match.
*/
blk->magic = INT_GET(curr->magic, ARCH_CONVERT);
if (INT_GET(curr->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC) {
node = blk->bp->data;
blk->hashval = INT_GET(node->btree[ INT_GET(node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
/*
* Binary search. (note: small blocks will skip loop)
*/
max = INT_GET(node->hdr.count, ARCH_CONVERT);
probe = span = max / 2;
hashval = state->args->hashval;
for (btree = &node->btree[probe]; span > 4;
btree = &node->btree[probe]) {
span /= 2;
if (INT_GET(btree->hashval, ARCH_CONVERT) < hashval)
probe += span;
else if (INT_GET(btree->hashval, ARCH_CONVERT) > hashval)
probe -= span;
else
break;
}
ASSERT((probe >= 0) && (probe < max));
ASSERT((span <= 4) || (INT_GET(btree->hashval, ARCH_CONVERT) == hashval));
/*
* Since we may have duplicate hashval's, find the first
* matching hashval in the node.
*/
while ((probe > 0) && (INT_GET(btree->hashval, ARCH_CONVERT) >= hashval)) {
btree--;
probe--;
}
while ((probe < max) && (INT_GET(btree->hashval, ARCH_CONVERT) < hashval)) {
btree++;
probe++;
}
/*
* Pick the right block to descend on.
*/
if (probe == max) {
blk->index = max-1;
blkno = INT_GET(node->btree[ max-1 ].before, ARCH_CONVERT);
} else {
blk->index = probe;
blkno = INT_GET(btree->before, ARCH_CONVERT);
}
}
#ifdef __KERNEL__
else if (INT_GET(curr->magic, ARCH_CONVERT) == XFS_ATTR_LEAF_MAGIC) {
blk->hashval = xfs_attr_leaf_lasthash(blk->bp, NULL);
break;
}
#endif
else if (INT_GET(curr->magic, ARCH_CONVERT) == XFS_DIR_LEAF_MAGIC) {
blk->hashval = xfs_dir_leaf_lasthash(blk->bp, NULL);
break;
}
else if (INT_GET(curr->magic, ARCH_CONVERT) == 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_DIR_LEAF_MAGIC) {
ASSERT(XFS_DIR_IS_V1(state->mp));
retval = xfs_dir_leaf_lookup_int(blk->bp, state->args,
&blk->index);
} else if (blk->magic == XFS_DIR2_LEAFN_MAGIC) {
ASSERT(XFS_DIR_IS_V2(state->mp));
retval = xfs_dir2_leafn_lookup_int(blk->bp, state->args,
&blk->index, state);
}
#ifdef __KERNEL__
else if (blk->magic == XFS_ATTR_LEAF_MAGIC) {
retval = xfs_attr_leaf_lookup_int(blk->bp, state->args);
blk->index = state->args->index;
state->args->blkno = blk->blkno;
}
#endif
if (((retval == ENOENT) || (retval == ENOATTR)) &&
(blk->hashval == state->args->hashval)) {
error = xfs_da_path_shift(state, &state->path, 1, 1,
&retval);
if (error)
return(error);
if (retval == 0) {
continue;
}
#ifdef __KERNEL__
else if (blk->magic == XFS_ATTR_LEAF_MAGIC) {
/* path_shift() gives ENOENT */
retval = XFS_ERROR(ENOATTR);
}
#endif
}
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_DIRX_LEAF_MAGIC(state->mp) ||
old_blk->magic == XFS_ATTR_LEAF_MAGIC);
ASSERT(old_blk->magic == INT_GET(old_info->magic, ARCH_CONVERT));
ASSERT(new_blk->magic == INT_GET(new_info->magic, ARCH_CONVERT));
ASSERT(old_blk->magic == new_blk->magic);
switch (old_blk->magic) {
#ifdef __KERNEL__
case XFS_ATTR_LEAF_MAGIC:
before = xfs_attr_leaf_order(old_blk->bp, new_blk->bp);
break;
#endif
case XFS_DIR_LEAF_MAGIC:
ASSERT(XFS_DIR_IS_V1(state->mp));
before = xfs_dir_leaf_order(old_blk->bp, new_blk->bp);
break;
case XFS_DIR2_LEAFN_MAGIC:
ASSERT(XFS_DIR_IS_V2(state->mp));
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.
*/
INT_SET(new_info->forw, ARCH_CONVERT, old_blk->blkno);
new_info->back = old_info->back; /* INT_: direct copy */
if (INT_GET(old_info->back, ARCH_CONVERT)) {
error = xfs_da_read_buf(args->trans, args->dp,
INT_GET(old_info->back,
ARCH_CONVERT), -1, &bp,
args->whichfork);
if (error)
return(error);
ASSERT(bp != NULL);
tmp_info = bp->data;
ASSERT(INT_GET(tmp_info->magic, ARCH_CONVERT) == INT_GET(old_info->magic, ARCH_CONVERT));
ASSERT(INT_GET(tmp_info->forw, ARCH_CONVERT) == old_blk->blkno);
INT_SET(tmp_info->forw, ARCH_CONVERT, new_blk->blkno);
xfs_da_log_buf(args->trans, bp, 0, sizeof(*tmp_info)-1);
xfs_da_buf_done(bp);
}
INT_SET(old_info->back, ARCH_CONVERT, new_blk->blkno);
} else {
/*
* Link new block in after existing block.
*/
new_info->forw = old_info->forw; /* INT_: direct copy */
INT_SET(new_info->back, ARCH_CONVERT, old_blk->blkno);
if (INT_GET(old_info->forw, ARCH_CONVERT)) {
error = xfs_da_read_buf(args->trans, args->dp,
INT_GET(old_info->forw, ARCH_CONVERT), -1, &bp,
args->whichfork);
if (error)
return(error);
ASSERT(bp != NULL);
tmp_info = bp->data;
ASSERT(INT_GET(tmp_info->magic, ARCH_CONVERT)
== INT_GET(old_info->magic, ARCH_CONVERT));
ASSERT(INT_GET(tmp_info->back, ARCH_CONVERT)
== old_blk->blkno);
INT_SET(tmp_info->back, ARCH_CONVERT, new_blk->blkno);
xfs_da_log_buf(args->trans, bp, 0, sizeof(*tmp_info)-1);
xfs_da_buf_done(bp);
}
INT_SET(old_info->forw, ARCH_CONVERT, 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((INT_GET(node1->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC) &&
(INT_GET(node2->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC));
if ((INT_GET(node1->hdr.count, ARCH_CONVERT) > 0) && (INT_GET(node2->hdr.count, ARCH_CONVERT) > 0) &&
((INT_GET(node2->btree[ 0 ].hashval, ARCH_CONVERT) <
INT_GET(node1->btree[ 0 ].hashval, ARCH_CONVERT)) ||
(INT_GET(node2->btree[ INT_GET(node2->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT) <
INT_GET(node1->btree[ INT_GET(node1->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT)))) {
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(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
if (count)
*count = INT_GET(node->hdr.count, ARCH_CONVERT);
if (INT_GET(node->hdr.count, ARCH_CONVERT) == 0)
return(0);
return(INT_GET(node->btree[ INT_GET(node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT));
}
/*
* Unlink a block from a doubly linked list of blocks.
*/
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_DIRX_LEAF_MAGIC(state->mp) ||
save_blk->magic == XFS_ATTR_LEAF_MAGIC);
ASSERT(save_blk->magic == INT_GET(save_info->magic, ARCH_CONVERT));
ASSERT(drop_blk->magic == INT_GET(drop_info->magic, ARCH_CONVERT));
ASSERT(save_blk->magic == drop_blk->magic);
ASSERT((INT_GET(save_info->forw, ARCH_CONVERT) == drop_blk->blkno) ||
(INT_GET(save_info->back, ARCH_CONVERT) == drop_blk->blkno));
ASSERT((INT_GET(drop_info->forw, ARCH_CONVERT) == save_blk->blkno) ||
(INT_GET(drop_info->back, ARCH_CONVERT) == save_blk->blkno));
/*
* Unlink the leaf block from the doubly linked chain of leaves.
*/
if (INT_GET(save_info->back, ARCH_CONVERT) == drop_blk->blkno) {
save_info->back = drop_info->back; /* INT_: direct copy */
if (INT_GET(drop_info->back, ARCH_CONVERT)) {
error = xfs_da_read_buf(args->trans, args->dp,
INT_GET(drop_info->back,
ARCH_CONVERT), -1, &bp,
args->whichfork);
if (error)
return(error);
ASSERT(bp != NULL);
tmp_info = bp->data;
ASSERT(INT_GET(tmp_info->magic, ARCH_CONVERT) == INT_GET(save_info->magic, ARCH_CONVERT));
ASSERT(INT_GET(tmp_info->forw, ARCH_CONVERT) == drop_blk->blkno);
INT_SET(tmp_info->forw, ARCH_CONVERT, 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; /* INT_: direct copy */
if (INT_GET(drop_info->forw, ARCH_CONVERT)) {
error = xfs_da_read_buf(args->trans, args->dp,
INT_GET(drop_info->forw, ARCH_CONVERT), -1, &bp,
args->whichfork);
if (error)
return(error);
ASSERT(bp != NULL);
tmp_info = bp->data;
ASSERT(INT_GET(tmp_info->magic, ARCH_CONVERT)
== INT_GET(save_info->magic, ARCH_CONVERT));
ASSERT(INT_GET(tmp_info->back, ARCH_CONVERT)
== drop_blk->blkno);
INT_SET(tmp_info->back, ARCH_CONVERT, 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(INT_GET(node->hdr.info.magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
if (forward && (blk->index < INT_GET(node->hdr.count, ARCH_CONVERT)-1)) {
blk->index++;
blkno = INT_GET(node->btree[ blk->index ].before, ARCH_CONVERT);
break;
} else if (!forward && (blk->index > 0)) {
blk->index--;
blkno = INT_GET(node->btree[ blk->index ].before, ARCH_CONVERT);
break;
}
}
if (level < 0) {
*result = XFS_ERROR(ENOENT); /* we're out of our tree */
ASSERT(args->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(INT_GET(info->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC ||
INT_GET(info->magic, ARCH_CONVERT) == XFS_DIRX_LEAF_MAGIC(state->mp) ||
INT_GET(info->magic, ARCH_CONVERT) == XFS_ATTR_LEAF_MAGIC);
blk->magic = INT_GET(info->magic, ARCH_CONVERT);
if (INT_GET(info->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC) {
node = (xfs_da_intnode_t *)info;
blk->hashval = INT_GET(node->btree[ INT_GET(node->hdr.count, ARCH_CONVERT)-1 ].hashval, ARCH_CONVERT);
if (forward)
blk->index = 0;
else
blk->index = INT_GET(node->hdr.count, ARCH_CONVERT)-1;
blkno = INT_GET(node->btree[ blk->index ].before, ARCH_CONVERT);
} else {
ASSERT(level == path->active-1);
blk->index = 0;
switch(blk->magic) {
#ifdef __KERNEL__
case XFS_ATTR_LEAF_MAGIC:
blk->hashval = xfs_attr_leaf_lasthash(blk->bp,
NULL);
break;
#endif
case XFS_DIR_LEAF_MAGIC:
ASSERT(XFS_DIR_IS_V1(state->mp));
blk->hashval = xfs_dir_leaf_lasthash(blk->bp,
NULL);
break;
case XFS_DIR2_LEAFN_MAGIC:
ASSERT(XFS_DIR_IS_V2(state->mp));
blk->hashval = xfs_dir2_leafn_lasthash(blk->bp,
NULL);
break;
default:
ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC ||
blk->magic ==
XFS_DIRX_LEAF_MAGIC(state->mp));
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(uchar_t *name, int namelen)
{
xfs_dahash_t hash;
#define ROTL(x,y) (((x) << (y)) | ((x) >> (32 - (y))))
#ifdef SLOWVERSION
/*
* This is the old one-byte-at-a-time version.
*/
for (hash = 0; namelen > 0; namelen--) {
hash = *name++ ^ ROTL(hash, 7);
}
return(hash);
#else
/*
* 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) ^ ROTL(hash, 7 * 4);
}
/*
* Now do the rest of the characters.
*/
switch (namelen) {
case 3:
return (name[0] << 14) ^ (name[1] << 7) ^ (name[2] << 0) ^
ROTL(hash, 7 * 3);
case 2:
return (name[0] << 7) ^ (name[1] << 0) ^ ROTL(hash, 7 * 2);
case 1:
return (name[0] << 0) ^ ROTL(hash, 7 * 1);
case 0:
return hash;
}
/* NOTREACHED */
#endif
#undef ROTL
return 0; /* keep gcc happy */
}
/*
* 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_fsize_t size;
xfs_trans_t *tp;
xfs_mount_t *mp;
dp = args->dp;
mp = dp->i_mount;
w = args->whichfork;
tp = args->trans;
/*
* For new directories adjust the file offset and block count.
*/
if (w == XFS_DATA_FORK && XFS_DIR_IS_V2(mp)) {
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 && XFS_DIR_IS_V2(mp))
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 = ↦
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, sizeof(*mapp) * count);
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, sizeof(*mapp) * count);
return XFS_ERROR(ENOSPC);
}
if (mapp != &map)
kmem_free(mapp, sizeof(*mapp) * count);
*new_blkno = (xfs_dablk_t)bno;
/*
* For version 1 directories, adjust the file size if it changed.
*/
if (w == XFS_DATA_FORK && XFS_DIR_IS_V1(mp)) {
ASSERT(mapi == 1);
if ((error = xfs_bmap_last_offset(tp, dp, &bno, w)))
return error;
size = XFS_FSB_TO_B(mp, bno);
if (size != dp->i_d.di_size) {
dp->i_d.di_size = size;
xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
}
}
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_dir_leafblock_t *dead_leaf;
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;
if (XFS_DIR_IS_V2(mp)) {
lastoff = mp->m_dirfreeblk;
error = xfs_bmap_last_before(tp, ip, &lastoff, w);
} else
error = xfs_bmap_last_offset(tp, ip, &lastoff, w);
if (error)
return error;
if (lastoff == 0)
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.
*/
bcopy(last_buf->data, dead_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 (INT_GET(dead_info->magic, ARCH_CONVERT) == XFS_DIR_LEAF_MAGIC) {
ASSERT(XFS_DIR_IS_V1(mp));
dead_leaf = (xfs_dir_leafblock_t *)dead_info;
dead_level = 0;
dead_hash =
INT_GET(dead_leaf->entries[INT_GET(dead_leaf->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT);
} else if (INT_GET(dead_info->magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC) {
ASSERT(XFS_DIR_IS_V2(mp));
dead_leaf2 = (xfs_dir2_leaf_t *)dead_info;
dead_level = 0;
dead_hash = INT_GET(dead_leaf2->ents[INT_GET(dead_leaf2->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT);
} else {
ASSERT(INT_GET(dead_info->magic, ARCH_CONVERT) == XFS_DA_NODE_MAGIC);
dead_node = (xfs_da_intnode_t *)dead_info;
dead_level = INT_GET(dead_node->hdr.level, ARCH_CONVERT);
dead_hash = INT_GET(dead_node->btree[INT_GET(dead_node->hdr.count, ARCH_CONVERT) - 1].hashval, ARCH_CONVERT);
}
sib_buf = par_buf = NULL;
/*
* If the moved block has a left sibling, fix up the pointers.
*/
if ((sib_blkno = INT_GET(dead_info->back, ARCH_CONVERT))) {
if ((error = xfs_da_read_buf(tp, ip, sib_blkno, -1, &sib_buf, w)))
goto done;
sib_info = sib_buf->data;
if (INT_GET(sib_info->forw, ARCH_CONVERT) != last_blkno ||
INT_GET(sib_info->magic, ARCH_CONVERT) != INT_GET(dead_info->magic, ARCH_CONVERT)) {
error = XFS_ERROR(EFSCORRUPTED);
goto done;
}
INT_SET(sib_info->forw, ARCH_CONVERT, 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 = INT_GET(dead_info->forw, ARCH_CONVERT))) {
if ((error = xfs_da_read_buf(tp, ip, sib_blkno, -1, &sib_buf, w)))
goto done;
sib_info = sib_buf->data;
if ( INT_GET(sib_info->back, ARCH_CONVERT) != last_blkno
|| INT_GET(sib_info->magic, ARCH_CONVERT)
!= INT_GET(dead_info->magic, ARCH_CONVERT)) {
error = XFS_ERROR(EFSCORRUPTED);
goto done;
}
INT_SET(sib_info->back, ARCH_CONVERT, 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 = XFS_DIR_IS_V1(mp) ? 0 : 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 (INT_GET(par_node->hdr.info.magic, ARCH_CONVERT) != XFS_DA_NODE_MAGIC ||
(level >= 0 && level != INT_GET(par_node->hdr.level, ARCH_CONVERT) + 1)) {
error = XFS_ERROR(EFSCORRUPTED);
goto done;
}
level = INT_GET(par_node->hdr.level, ARCH_CONVERT);
for (entno = 0;
entno < INT_GET(par_node->hdr.count, ARCH_CONVERT) &&
INT_GET(par_node->btree[entno].hashval, ARCH_CONVERT) < dead_hash;
entno++)
continue;
if (entno == INT_GET(par_node->hdr.count, ARCH_CONVERT)) {
error = XFS_ERROR(EFSCORRUPTED);
goto done;
}
par_blkno = INT_GET(par_node->btree[entno].before, ARCH_CONVERT);
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 < INT_GET(par_node->hdr.count, ARCH_CONVERT) &&
INT_GET(par_node->btree[entno].before, ARCH_CONVERT) != last_blkno;
entno++)
continue;
if (entno < INT_GET(par_node->hdr.count, ARCH_CONVERT))
break;
par_blkno = INT_GET(par_node->hdr.info.forw, ARCH_CONVERT);
xfs_da_brelse(tp, par_buf);
par_buf = NULL;
if (par_blkno == 0) {
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 (INT_GET(par_node->hdr.level, ARCH_CONVERT) != level ||
INT_GET(par_node->hdr.info.magic, ARCH_CONVERT) != XFS_DA_NODE_MAGIC) {
error = XFS_ERROR(EFSCORRUPTED);
goto done;
}
entno = 0;
}
/*
* Update the parent entry pointing to the moved block.
*/
INT_SET(par_node->btree[entno].before, ARCH_CONVERT, 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_fileoff_t bno;
xfs_fsize_t size;
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 && XFS_DIR_IS_V2(mp))
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)
goto done;
if ((error = xfs_da_swap_lastblock(args, &dead_blkno,
&dead_buf)))
goto done;
} else if (error)
goto done;
else
break;
}
ASSERT(done);
xfs_da_binval(tp, dead_buf);
/*
* Adjust the directory size for version 1.
*/
if (w == XFS_DATA_FORK && XFS_DIR_IS_V1(mp)) {
if ((error = xfs_bmap_last_offset(tp, dp, &bno, w)))
return error;
size = XFS_FSB_TO_B(dp->i_mount, bno);
if (size != dp->i_d.di_size) {
dp->i_d.di_size = size;
xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
}
}
return 0;
done:
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 = 0;
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;
if (whichfork == XFS_DATA_FORK && XFS_DIR_IS_V2(mp))
nfsb = mp->m_dirblkfsbs;
else
nfsb = 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 = ↦
if (fsb == NULLFSBLOCK) {
nmap = 0;
} else {
map.br_startblock = fsb;
map.br_startoff = (xfs_fileoff_t)bno;
map.br_blockcount = 1;
nmap = 1;
}
} else {
xfs_fsblock_t firstblock;
firstblock = NULLFSBLOCK;
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),
&firstblock, 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 = ↦
nmap = 1;
}
if (!xfs_da_map_covers_blocks(nmap, mapp, bno, nfsb)) {
error = mappedbno == -2 ? 0 : XFS_ERROR(EFSCORRUPTED);
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:
#ifndef __KERNEL__
case 2:
#endif
bp = NULL;
error = xfs_trans_read_buf(mp, trans, mp->m_ddev_targp,
mappedbno, nmapped, 0, &bp);
break;
#ifdef __KERNEL__
case 3:
xfs_baread(mp->m_ddev_targp, mappedbno, nmapped);
error = 0;
bp = NULL;
break;
#endif
}
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;
info = rbp->data;
data = rbp->data;
free = rbp->data;
if (XFS_TEST_ERROR((INT_GET(info->magic, ARCH_CONVERT) != XFS_DA_NODE_MAGIC) &&
(INT_GET(info->magic, ARCH_CONVERT) != XFS_DIR_LEAF_MAGIC) &&
(INT_GET(info->magic, ARCH_CONVERT) != XFS_ATTR_LEAF_MAGIC) &&
(INT_GET(info->magic, ARCH_CONVERT) != XFS_DIR2_LEAF1_MAGIC) &&
(INT_GET(info->magic, ARCH_CONVERT) != XFS_DIR2_LEAFN_MAGIC) &&
(INT_GET(data->hdr.magic, ARCH_CONVERT) != XFS_DIR2_BLOCK_MAGIC) &&
(INT_GET(data->hdr.magic, ARCH_CONVERT) != XFS_DIR2_DATA_MAGIC) &&
(INT_GET(free->hdr.magic, ARCH_CONVERT) != XFS_DIR2_FREE_MAGIC),
mp, XFS_ERRTAG_DA_READ_BUF,
XFS_RANDOM_DA_READ_BUF)) {
xfs_buftrace("DA READ ERROR", rbp->bps[0]);
error = XFS_ERROR(EFSCORRUPTED);
xfs_da_brelse(trans, rbp);
nbplist = 0;
goto exit1;
}
}
if (bplist) {
kmem_free(bplist, sizeof(*bplist) * nmap);
}
if (mapp != &map) {
kmem_free(mapp, sizeof(*mapp) * nfsb);
}
if (bpp)
*bpp = rbp;
return 0;
exit1:
if (bplist) {
for (i = 0; i < nbplist; i++)
xfs_trans_brelse(trans, bplist[i]);
kmem_free(bplist, sizeof(*bplist) * nmap);
}
exit0:
if (mapp != &map)
kmem_free(mapp, sizeof(*mapp) * nfsb);
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;
}
/*
* Calculate the number of bits needed to hold i different values.
*/
uint
xfs_da_log2_roundup(uint i)
{
uint rval;
for (rval = 0; rval < NBBY * sizeof(i); rval++) {
if ((1 << rval) >= i)
break;
}
return(rval);
}
xfs_zone_t *xfs_da_state_zone; /* anchor for state struct zone */
xfs_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_SLEEP);
}
/*
* Kill the altpath contents of a da-state structure.
*/
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
bzero((char *)state, sizeof(*state));
#endif /* DEBUG */
kmem_zone_free(xfs_da_state_zone, state);
}
#ifdef XFS_DABUF_DEBUG
xfs_dabuf_t *xfs_dabuf_global_list;
lock_t 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_SLEEP);
else
dabuf = kmem_alloc(XFS_DA_BUF_SIZE(nbuf), KM_SLEEP);
dabuf->dirty = 0;
#ifdef XFS_DABUF_DEBUG
dabuf->ra = ra;
dabuf->dev = 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];
bcopy(XFS_BUF_PTR(bp), (char *)dabuf->data + off,
XFS_BUF_COUNT(bp));
}
}
#ifdef XFS_DABUF_DEBUG
{
int s;
xfs_dabuf_t *p;
s = mutex_spinlock(&xfs_dabuf_global_lock);
for (p = xfs_dabuf_global_list; p; p = p->next) {
ASSERT(p->blkno != dabuf->blkno ||
p->dev != dabuf->dev);
}
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;
mutex_spinunlock(&xfs_dabuf_global_lock, s);
}
#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];
bcopy((char *)dabuf->data + off, XFS_BUF_PTR(bp),
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, BBTOB(dabuf->bbcount));
#ifdef XFS_DABUF_DEBUG
{
int s;
s = mutex_spinlock(&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;
mutex_spinunlock(&xfs_dabuf_global_lock, s);
}
bzero(dabuf, XFS_DA_BUF_SIZE(dabuf->nbuf));
#endif
if (dabuf->nbuf == 1)
kmem_zone_free(xfs_dabuf_zone, dabuf);
else
kmem_free(dabuf, XFS_DA_BUF_SIZE(dabuf->nbuf));
}
/*
* 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);
bcopy(dabuf->bps, bplist, 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, nbuf * sizeof(*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);
bcopy(dabuf->bps, bplist, 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, nbuf * sizeof(*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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