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xfs_dir2_node.c
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xfs_dir2_node.c
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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_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_dir2.h"
#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_da_btree.h"
#include "xfs_bmap_btree.h"
#include "xfs_dir2_sf.h"
#include "xfs_attr_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_bmap.h"
#include "xfs_dir2_data.h"
#include "xfs_dir2_leaf.h"
#include "xfs_dir2_block.h"
#include "xfs_dir2_node.h"
#include "xfs_dir2_trace.h"
#include "xfs_error.h"
/*
* Function declarations.
*/
static void xfs_dir2_free_log_header(xfs_trans_t *tp, xfs_dabuf_t *bp);
static int xfs_dir2_leafn_add(xfs_dabuf_t *bp, xfs_da_args_t *args, int index);
#ifdef DEBUG
static void xfs_dir2_leafn_check(xfs_inode_t *dp, xfs_dabuf_t *bp);
#else
#define xfs_dir2_leafn_check(dp, bp)
#endif
static void xfs_dir2_leafn_moveents(xfs_da_args_t *args, xfs_dabuf_t *bp_s,
int start_s, xfs_dabuf_t *bp_d, int start_d,
int count);
static void xfs_dir2_leafn_rebalance(xfs_da_state_t *state,
xfs_da_state_blk_t *blk1,
xfs_da_state_blk_t *blk2);
static int xfs_dir2_leafn_remove(xfs_da_args_t *args, xfs_dabuf_t *bp,
int index, xfs_da_state_blk_t *dblk,
int *rval);
static int xfs_dir2_node_addname_int(xfs_da_args_t *args,
xfs_da_state_blk_t *fblk);
/*
* Log entries from a freespace block.
*/
void
xfs_dir2_free_log_bests(
xfs_trans_t *tp, /* transaction pointer */
xfs_dabuf_t *bp, /* freespace buffer */
int first, /* first entry to log */
int last) /* last entry to log */
{
xfs_dir2_free_t *free; /* freespace structure */
free = bp->data;
ASSERT(be32_to_cpu(free->hdr.magic) == XFS_DIR2_FREE_MAGIC);
xfs_da_log_buf(tp, bp,
(uint)((char *)&free->bests[first] - (char *)free),
(uint)((char *)&free->bests[last] - (char *)free +
sizeof(free->bests[0]) - 1));
}
/*
* Log header from a freespace block.
*/
static void
xfs_dir2_free_log_header(
xfs_trans_t *tp, /* transaction pointer */
xfs_dabuf_t *bp) /* freespace buffer */
{
xfs_dir2_free_t *free; /* freespace structure */
free = bp->data;
ASSERT(be32_to_cpu(free->hdr.magic) == XFS_DIR2_FREE_MAGIC);
xfs_da_log_buf(tp, bp, (uint)((char *)&free->hdr - (char *)free),
(uint)(sizeof(xfs_dir2_free_hdr_t) - 1));
}
/*
* Convert a leaf-format directory to a node-format directory.
* We need to change the magic number of the leaf block, and copy
* the freespace table out of the leaf block into its own block.
*/
int /* error */
xfs_dir2_leaf_to_node(
xfs_da_args_t *args, /* operation arguments */
xfs_dabuf_t *lbp) /* leaf buffer */
{
xfs_inode_t *dp; /* incore directory inode */
int error; /* error return value */
xfs_dabuf_t *fbp; /* freespace buffer */
xfs_dir2_db_t fdb; /* freespace block number */
xfs_dir2_free_t *free; /* freespace structure */
__be16 *from; /* pointer to freespace entry */
int i; /* leaf freespace index */
xfs_dir2_leaf_t *leaf; /* leaf structure */
xfs_dir2_leaf_tail_t *ltp; /* leaf tail structure */
xfs_mount_t *mp; /* filesystem mount point */
int n; /* count of live freespc ents */
xfs_dir2_data_off_t off; /* freespace entry value */
__be16 *to; /* pointer to freespace entry */
xfs_trans_t *tp; /* transaction pointer */
xfs_dir2_trace_args_b("leaf_to_node", args, lbp);
dp = args->dp;
mp = dp->i_mount;
tp = args->trans;
/*
* Add a freespace block to the directory.
*/
if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE, &fdb))) {
return error;
}
ASSERT(fdb == XFS_DIR2_FREE_FIRSTDB(mp));
/*
* Get the buffer for the new freespace block.
*/
if ((error = xfs_da_get_buf(tp, dp, XFS_DIR2_DB_TO_DA(mp, fdb), -1, &fbp,
XFS_DATA_FORK))) {
return error;
}
ASSERT(fbp != NULL);
free = fbp->data;
leaf = lbp->data;
ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
/*
* Initialize the freespace block header.
*/
free->hdr.magic = cpu_to_be32(XFS_DIR2_FREE_MAGIC);
free->hdr.firstdb = 0;
ASSERT(be32_to_cpu(ltp->bestcount) <= (uint)dp->i_d.di_size / mp->m_dirblksize);
free->hdr.nvalid = ltp->bestcount;
/*
* Copy freespace entries from the leaf block to the new block.
* Count active entries.
*/
for (i = n = 0, from = XFS_DIR2_LEAF_BESTS_P(ltp), to = free->bests;
i < be32_to_cpu(ltp->bestcount); i++, from++, to++) {
if ((off = be16_to_cpu(*from)) != NULLDATAOFF)
n++;
*to = cpu_to_be16(off);
}
free->hdr.nused = cpu_to_be32(n);
leaf->hdr.info.magic = cpu_to_be16(XFS_DIR2_LEAFN_MAGIC);
/*
* Log everything.
*/
xfs_dir2_leaf_log_header(tp, lbp);
xfs_dir2_free_log_header(tp, fbp);
xfs_dir2_free_log_bests(tp, fbp, 0, be32_to_cpu(free->hdr.nvalid) - 1);
xfs_da_buf_done(fbp);
xfs_dir2_leafn_check(dp, lbp);
return 0;
}
/*
* Add a leaf entry to a leaf block in a node-form directory.
* The other work necessary is done from the caller.
*/
static int /* error */
xfs_dir2_leafn_add(
xfs_dabuf_t *bp, /* leaf buffer */
xfs_da_args_t *args, /* operation arguments */
int index) /* insertion pt for new entry */
{
int compact; /* compacting stale leaves */
xfs_inode_t *dp; /* incore directory inode */
int highstale; /* next stale entry */
xfs_dir2_leaf_t *leaf; /* leaf structure */
xfs_dir2_leaf_entry_t *lep; /* leaf entry */
int lfloghigh; /* high leaf entry logging */
int lfloglow; /* low leaf entry logging */
int lowstale; /* previous stale entry */
xfs_mount_t *mp; /* filesystem mount point */
xfs_trans_t *tp; /* transaction pointer */
xfs_dir2_trace_args_sb("leafn_add", args, index, bp);
dp = args->dp;
mp = dp->i_mount;
tp = args->trans;
leaf = bp->data;
/*
* Quick check just to make sure we are not going to index
* into other peoples memory
*/
if (index < 0)
return XFS_ERROR(EFSCORRUPTED);
/*
* If there are already the maximum number of leaf entries in
* the block, if there are no stale entries it won't fit.
* Caller will do a split. If there are stale entries we'll do
* a compact.
*/
if (be16_to_cpu(leaf->hdr.count) == XFS_DIR2_MAX_LEAF_ENTS(mp)) {
if (!leaf->hdr.stale)
return XFS_ERROR(ENOSPC);
compact = be16_to_cpu(leaf->hdr.stale) > 1;
} else
compact = 0;
ASSERT(index == 0 || be32_to_cpu(leaf->ents[index - 1].hashval) <= args->hashval);
ASSERT(index == be16_to_cpu(leaf->hdr.count) ||
be32_to_cpu(leaf->ents[index].hashval) >= args->hashval);
if (args->justcheck)
return 0;
/*
* Compact out all but one stale leaf entry. Leaves behind
* the entry closest to index.
*/
if (compact) {
xfs_dir2_leaf_compact_x1(bp, &index, &lowstale, &highstale,
&lfloglow, &lfloghigh);
}
/*
* Set impossible logging indices for this case.
*/
else if (leaf->hdr.stale) {
lfloglow = be16_to_cpu(leaf->hdr.count);
lfloghigh = -1;
}
/*
* No stale entries, just insert a space for the new entry.
*/
if (!leaf->hdr.stale) {
lep = &leaf->ents[index];
if (index < be16_to_cpu(leaf->hdr.count))
memmove(lep + 1, lep,
(be16_to_cpu(leaf->hdr.count) - index) * sizeof(*lep));
lfloglow = index;
lfloghigh = be16_to_cpu(leaf->hdr.count);
be16_add(&leaf->hdr.count, 1);
}
/*
* There are stale entries. We'll use one for the new entry.
*/
else {
/*
* If we didn't do a compact then we need to figure out
* which stale entry will be used.
*/
if (compact == 0) {
/*
* Find first stale entry before our insertion point.
*/
for (lowstale = index - 1;
lowstale >= 0 &&
be32_to_cpu(leaf->ents[lowstale].address) !=
XFS_DIR2_NULL_DATAPTR;
lowstale--)
continue;
/*
* Find next stale entry after insertion point.
* Stop looking if the answer would be worse than
* lowstale already found.
*/
for (highstale = index;
highstale < be16_to_cpu(leaf->hdr.count) &&
be32_to_cpu(leaf->ents[highstale].address) !=
XFS_DIR2_NULL_DATAPTR &&
(lowstale < 0 ||
index - lowstale - 1 >= highstale - index);
highstale++)
continue;
}
/*
* Using the low stale entry.
* Shift entries up toward the stale slot.
*/
if (lowstale >= 0 &&
(highstale == be16_to_cpu(leaf->hdr.count) ||
index - lowstale - 1 < highstale - index)) {
ASSERT(be32_to_cpu(leaf->ents[lowstale].address) ==
XFS_DIR2_NULL_DATAPTR);
ASSERT(index - lowstale - 1 >= 0);
if (index - lowstale - 1 > 0)
memmove(&leaf->ents[lowstale],
&leaf->ents[lowstale + 1],
(index - lowstale - 1) * sizeof(*lep));
lep = &leaf->ents[index - 1];
lfloglow = MIN(lowstale, lfloglow);
lfloghigh = MAX(index - 1, lfloghigh);
}
/*
* Using the high stale entry.
* Shift entries down toward the stale slot.
*/
else {
ASSERT(be32_to_cpu(leaf->ents[highstale].address) ==
XFS_DIR2_NULL_DATAPTR);
ASSERT(highstale - index >= 0);
if (highstale - index > 0)
memmove(&leaf->ents[index + 1],
&leaf->ents[index],
(highstale - index) * sizeof(*lep));
lep = &leaf->ents[index];
lfloglow = MIN(index, lfloglow);
lfloghigh = MAX(highstale, lfloghigh);
}
be16_add(&leaf->hdr.stale, -1);
}
/*
* Insert the new entry, log everything.
*/
lep->hashval = cpu_to_be32(args->hashval);
lep->address = cpu_to_be32(XFS_DIR2_DB_OFF_TO_DATAPTR(mp,
args->blkno, args->index));
xfs_dir2_leaf_log_header(tp, bp);
xfs_dir2_leaf_log_ents(tp, bp, lfloglow, lfloghigh);
xfs_dir2_leafn_check(dp, bp);
return 0;
}
#ifdef DEBUG
/*
* Check internal consistency of a leafn block.
*/
void
xfs_dir2_leafn_check(
xfs_inode_t *dp, /* incore directory inode */
xfs_dabuf_t *bp) /* leaf buffer */
{
int i; /* leaf index */
xfs_dir2_leaf_t *leaf; /* leaf structure */
xfs_mount_t *mp; /* filesystem mount point */
int stale; /* count of stale leaves */
leaf = bp->data;
mp = dp->i_mount;
ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
ASSERT(be16_to_cpu(leaf->hdr.count) <= XFS_DIR2_MAX_LEAF_ENTS(mp));
for (i = stale = 0; i < be16_to_cpu(leaf->hdr.count); i++) {
if (i + 1 < be16_to_cpu(leaf->hdr.count)) {
ASSERT(be32_to_cpu(leaf->ents[i].hashval) <=
be32_to_cpu(leaf->ents[i + 1].hashval));
}
if (be32_to_cpu(leaf->ents[i].address) == XFS_DIR2_NULL_DATAPTR)
stale++;
}
ASSERT(be16_to_cpu(leaf->hdr.stale) == stale);
}
#endif /* DEBUG */
/*
* Return the last hash value in the leaf.
* Stale entries are ok.
*/
xfs_dahash_t /* hash value */
xfs_dir2_leafn_lasthash(
xfs_dabuf_t *bp, /* leaf buffer */
int *count) /* count of entries in leaf */
{
xfs_dir2_leaf_t *leaf; /* leaf structure */
leaf = bp->data;
ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
if (count)
*count = be16_to_cpu(leaf->hdr.count);
if (!leaf->hdr.count)
return 0;
return be32_to_cpu(leaf->ents[be16_to_cpu(leaf->hdr.count) - 1].hashval);
}
/*
* Look up a leaf entry in a node-format leaf block.
* If this is an addname then the extrablk in state is a freespace block,
* otherwise it's a data block.
*/
int
xfs_dir2_leafn_lookup_int(
xfs_dabuf_t *bp, /* leaf buffer */
xfs_da_args_t *args, /* operation arguments */
int *indexp, /* out: leaf entry index */
xfs_da_state_t *state) /* state to fill in */
{
xfs_dabuf_t *curbp; /* current data/free buffer */
xfs_dir2_db_t curdb; /* current data block number */
xfs_dir2_db_t curfdb; /* current free block number */
xfs_dir2_data_entry_t *dep; /* data block entry */
xfs_inode_t *dp; /* incore directory inode */
int error; /* error return value */
int fi; /* free entry index */
xfs_dir2_free_t *free=NULL; /* free block structure */
int index; /* leaf entry index */
xfs_dir2_leaf_t *leaf; /* leaf structure */
int length=0; /* length of new data entry */
xfs_dir2_leaf_entry_t *lep; /* leaf entry */
xfs_mount_t *mp; /* filesystem mount point */
xfs_dir2_db_t newdb; /* new data block number */
xfs_dir2_db_t newfdb; /* new free block number */
xfs_trans_t *tp; /* transaction pointer */
dp = args->dp;
tp = args->trans;
mp = dp->i_mount;
leaf = bp->data;
ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
#ifdef __KERNEL__
ASSERT(be16_to_cpu(leaf->hdr.count) > 0);
#endif
xfs_dir2_leafn_check(dp, bp);
/*
* Look up the hash value in the leaf entries.
*/
index = xfs_dir2_leaf_search_hash(args, bp);
/*
* Do we have a buffer coming in?
*/
if (state->extravalid)
curbp = state->extrablk.bp;
else
curbp = NULL;
/*
* For addname, it's a free block buffer, get the block number.
*/
if (args->addname) {
curfdb = curbp ? state->extrablk.blkno : -1;
curdb = -1;
length = XFS_DIR2_DATA_ENTSIZE(args->namelen);
if ((free = (curbp ? curbp->data : NULL)))
ASSERT(be32_to_cpu(free->hdr.magic) == XFS_DIR2_FREE_MAGIC);
}
/*
* For others, it's a data block buffer, get the block number.
*/
else {
curfdb = -1;
curdb = curbp ? state->extrablk.blkno : -1;
}
/*
* Loop over leaf entries with the right hash value.
*/
for (lep = &leaf->ents[index];
index < be16_to_cpu(leaf->hdr.count) && be32_to_cpu(lep->hashval) == args->hashval;
lep++, index++) {
/*
* Skip stale leaf entries.
*/
if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
continue;
/*
* Pull the data block number from the entry.
*/
newdb = XFS_DIR2_DATAPTR_TO_DB(mp, be32_to_cpu(lep->address));
/*
* For addname, we're looking for a place to put the new entry.
* We want to use a data block with an entry of equal
* hash value to ours if there is one with room.
*/
if (args->addname) {
/*
* If this block isn't the data block we already have
* in hand, take a look at it.
*/
if (newdb != curdb) {
curdb = newdb;
/*
* Convert the data block to the free block
* holding its freespace information.
*/
newfdb = XFS_DIR2_DB_TO_FDB(mp, newdb);
/*
* If it's not the one we have in hand,
* read it in.
*/
if (newfdb != curfdb) {
/*
* If we had one before, drop it.
*/
if (curbp)
xfs_da_brelse(tp, curbp);
/*
* Read the free block.
*/
if ((error = xfs_da_read_buf(tp, dp,
XFS_DIR2_DB_TO_DA(mp,
newfdb),
-1, &curbp,
XFS_DATA_FORK))) {
return error;
}
free = curbp->data;
ASSERT(be32_to_cpu(free->hdr.magic) ==
XFS_DIR2_FREE_MAGIC);
ASSERT((be32_to_cpu(free->hdr.firstdb) %
XFS_DIR2_MAX_FREE_BESTS(mp)) ==
0);
ASSERT(be32_to_cpu(free->hdr.firstdb) <= curdb);
ASSERT(curdb <
be32_to_cpu(free->hdr.firstdb) +
be32_to_cpu(free->hdr.nvalid));
}
/*
* Get the index for our entry.
*/
fi = XFS_DIR2_DB_TO_FDINDEX(mp, curdb);
/*
* If it has room, return it.
*/
if (unlikely(be16_to_cpu(free->bests[fi]) == NULLDATAOFF)) {
XFS_ERROR_REPORT("xfs_dir2_leafn_lookup_int",
XFS_ERRLEVEL_LOW, mp);
if (curfdb != newfdb)
xfs_da_brelse(tp, curbp);
return XFS_ERROR(EFSCORRUPTED);
}
curfdb = newfdb;
if (be16_to_cpu(free->bests[fi]) >= length) {
*indexp = index;
state->extravalid = 1;
state->extrablk.bp = curbp;
state->extrablk.blkno = curfdb;
state->extrablk.index = fi;
state->extrablk.magic =
XFS_DIR2_FREE_MAGIC;
ASSERT(args->oknoent);
return XFS_ERROR(ENOENT);
}
}
}
/*
* Not adding a new entry, so we really want to find
* the name given to us.
*/
else {
/*
* If it's a different data block, go get it.
*/
if (newdb != curdb) {
/*
* If we had a block before, drop it.
*/
if (curbp)
xfs_da_brelse(tp, curbp);
/*
* Read the data block.
*/
if ((error =
xfs_da_read_buf(tp, dp,
XFS_DIR2_DB_TO_DA(mp, newdb), -1,
&curbp, XFS_DATA_FORK))) {
return error;
}
xfs_dir2_data_check(dp, curbp);
curdb = newdb;
}
/*
* Point to the data entry.
*/
dep = (xfs_dir2_data_entry_t *)
((char *)curbp->data +
XFS_DIR2_DATAPTR_TO_OFF(mp, be32_to_cpu(lep->address)));
/*
* Compare the entry, return it if it matches.
*/
if (dep->namelen == args->namelen &&
dep->name[0] == args->name[0] &&
memcmp(dep->name, args->name, args->namelen) == 0) {
args->inumber = be64_to_cpu(dep->inumber);
*indexp = index;
state->extravalid = 1;
state->extrablk.bp = curbp;
state->extrablk.blkno = curdb;
state->extrablk.index =
(int)((char *)dep -
(char *)curbp->data);
state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
return XFS_ERROR(EEXIST);
}
}
}
/*
* Didn't find a match.
* If we are holding a buffer, give it back in case our caller
* finds it useful.
*/
if ((state->extravalid = (curbp != NULL))) {
state->extrablk.bp = curbp;
state->extrablk.index = -1;
/*
* For addname, giving back a free block.
*/
if (args->addname) {
state->extrablk.blkno = curfdb;
state->extrablk.magic = XFS_DIR2_FREE_MAGIC;
}
/*
* For other callers, giving back a data block.
*/
else {
state->extrablk.blkno = curdb;
state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
}
}
/*
* Return the final index, that will be the insertion point.
*/
*indexp = index;
ASSERT(index == be16_to_cpu(leaf->hdr.count) || args->oknoent);
return XFS_ERROR(ENOENT);
}
/*
* Move count leaf entries from source to destination leaf.
* Log entries and headers. Stale entries are preserved.
*/
static void
xfs_dir2_leafn_moveents(
xfs_da_args_t *args, /* operation arguments */
xfs_dabuf_t *bp_s, /* source leaf buffer */
int start_s, /* source leaf index */
xfs_dabuf_t *bp_d, /* destination leaf buffer */
int start_d, /* destination leaf index */
int count) /* count of leaves to copy */
{
xfs_dir2_leaf_t *leaf_d; /* destination leaf structure */
xfs_dir2_leaf_t *leaf_s; /* source leaf structure */
int stale; /* count stale leaves copied */
xfs_trans_t *tp; /* transaction pointer */
xfs_dir2_trace_args_bibii("leafn_moveents", args, bp_s, start_s, bp_d,
start_d, count);
/*
* Silently return if nothing to do.
*/
if (count == 0) {
return;
}
tp = args->trans;
leaf_s = bp_s->data;
leaf_d = bp_d->data;
/*
* If the destination index is not the end of the current
* destination leaf entries, open up a hole in the destination
* to hold the new entries.
*/
if (start_d < be16_to_cpu(leaf_d->hdr.count)) {
memmove(&leaf_d->ents[start_d + count], &leaf_d->ents[start_d],
(be16_to_cpu(leaf_d->hdr.count) - start_d) *
sizeof(xfs_dir2_leaf_entry_t));
xfs_dir2_leaf_log_ents(tp, bp_d, start_d + count,
count + be16_to_cpu(leaf_d->hdr.count) - 1);
}
/*
* If the source has stale leaves, count the ones in the copy range
* so we can update the header correctly.
*/
if (leaf_s->hdr.stale) {
int i; /* temp leaf index */
for (i = start_s, stale = 0; i < start_s + count; i++) {
if (be32_to_cpu(leaf_s->ents[i].address) == XFS_DIR2_NULL_DATAPTR)
stale++;
}
} else
stale = 0;
/*
* Copy the leaf entries from source to destination.
*/
memcpy(&leaf_d->ents[start_d], &leaf_s->ents[start_s],
count * sizeof(xfs_dir2_leaf_entry_t));
xfs_dir2_leaf_log_ents(tp, bp_d, start_d, start_d + count - 1);
/*
* If there are source entries after the ones we copied,
* delete the ones we copied by sliding the next ones down.
*/
if (start_s + count < be16_to_cpu(leaf_s->hdr.count)) {
memmove(&leaf_s->ents[start_s], &leaf_s->ents[start_s + count],
count * sizeof(xfs_dir2_leaf_entry_t));
xfs_dir2_leaf_log_ents(tp, bp_s, start_s, start_s + count - 1);
}
/*
* Update the headers and log them.
*/
be16_add(&leaf_s->hdr.count, -(count));
be16_add(&leaf_s->hdr.stale, -(stale));
be16_add(&leaf_d->hdr.count, count);
be16_add(&leaf_d->hdr.stale, stale);
xfs_dir2_leaf_log_header(tp, bp_s);
xfs_dir2_leaf_log_header(tp, bp_d);
xfs_dir2_leafn_check(args->dp, bp_s);
xfs_dir2_leafn_check(args->dp, bp_d);
}
/*
* Determine the sort order of two leaf blocks.
* Returns 1 if both are valid and leaf2 should be before leaf1, else 0.
*/
int /* sort order */
xfs_dir2_leafn_order(
xfs_dabuf_t *leaf1_bp, /* leaf1 buffer */
xfs_dabuf_t *leaf2_bp) /* leaf2 buffer */
{
xfs_dir2_leaf_t *leaf1; /* leaf1 structure */
xfs_dir2_leaf_t *leaf2; /* leaf2 structure */
leaf1 = leaf1_bp->data;
leaf2 = leaf2_bp->data;
ASSERT(be16_to_cpu(leaf1->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
ASSERT(be16_to_cpu(leaf2->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
if (be16_to_cpu(leaf1->hdr.count) > 0 &&
be16_to_cpu(leaf2->hdr.count) > 0 &&
(be32_to_cpu(leaf2->ents[0].hashval) < be32_to_cpu(leaf1->ents[0].hashval) ||
be32_to_cpu(leaf2->ents[be16_to_cpu(leaf2->hdr.count) - 1].hashval) <
be32_to_cpu(leaf1->ents[be16_to_cpu(leaf1->hdr.count) - 1].hashval)))
return 1;
return 0;
}
/*
* Rebalance leaf entries between two leaf blocks.
* This is actually only called when the second block is new,
* though the code deals with the general case.
* A new entry will be inserted in one of the blocks, and that
* entry is taken into account when balancing.
*/
static void
xfs_dir2_leafn_rebalance(
xfs_da_state_t *state, /* btree cursor */
xfs_da_state_blk_t *blk1, /* first btree block */
xfs_da_state_blk_t *blk2) /* second btree block */
{
xfs_da_args_t *args; /* operation arguments */
int count; /* count (& direction) leaves */
int isleft; /* new goes in left leaf */
xfs_dir2_leaf_t *leaf1; /* first leaf structure */
xfs_dir2_leaf_t *leaf2; /* second leaf structure */
int mid; /* midpoint leaf index */
#ifdef DEBUG
int oldstale; /* old count of stale leaves */
#endif
int oldsum; /* old total leaf count */
int swap; /* swapped leaf blocks */
args = state->args;
/*
* If the block order is wrong, swap the arguments.
*/
if ((swap = xfs_dir2_leafn_order(blk1->bp, blk2->bp))) {
xfs_da_state_blk_t *tmp; /* temp for block swap */
tmp = blk1;
blk1 = blk2;
blk2 = tmp;
}
leaf1 = blk1->bp->data;
leaf2 = blk2->bp->data;
oldsum = be16_to_cpu(leaf1->hdr.count) + be16_to_cpu(leaf2->hdr.count);
#ifdef DEBUG
oldstale = be16_to_cpu(leaf1->hdr.stale) + be16_to_cpu(leaf2->hdr.stale);
#endif
mid = oldsum >> 1;
/*
* If the old leaf count was odd then the new one will be even,
* so we need to divide the new count evenly.
*/
if (oldsum & 1) {
xfs_dahash_t midhash; /* middle entry hash value */
if (mid >= be16_to_cpu(leaf1->hdr.count))
midhash = be32_to_cpu(leaf2->ents[mid - be16_to_cpu(leaf1->hdr.count)].hashval);
else
midhash = be32_to_cpu(leaf1->ents[mid].hashval);
isleft = args->hashval <= midhash;
}
/*
* If the old count is even then the new count is odd, so there's
* no preferred side for the new entry.
* Pick the left one.
*/
else
isleft = 1;
/*
* Calculate moved entry count. Positive means left-to-right,
* negative means right-to-left. Then move the entries.
*/
count = be16_to_cpu(leaf1->hdr.count) - mid + (isleft == 0);
if (count > 0)
xfs_dir2_leafn_moveents(args, blk1->bp,
be16_to_cpu(leaf1->hdr.count) - count, blk2->bp, 0, count);
else if (count < 0)
xfs_dir2_leafn_moveents(args, blk2->bp, 0, blk1->bp,
be16_to_cpu(leaf1->hdr.count), count);
ASSERT(be16_to_cpu(leaf1->hdr.count) + be16_to_cpu(leaf2->hdr.count) == oldsum);
ASSERT(be16_to_cpu(leaf1->hdr.stale) + be16_to_cpu(leaf2->hdr.stale) == oldstale);
/*
* Mark whether we're inserting into the old or new leaf.
*/
if (be16_to_cpu(leaf1->hdr.count) < be16_to_cpu(leaf2->hdr.count))
state->inleaf = swap;
else if (be16_to_cpu(leaf1->hdr.count) > be16_to_cpu(leaf2->hdr.count))
state->inleaf = !swap;
else
state->inleaf =
swap ^ (blk1->index <= be16_to_cpu(leaf1->hdr.count));
/*
* Adjust the expected index for insertion.
*/
if (!state->inleaf)
blk2->index = blk1->index - be16_to_cpu(leaf1->hdr.count);
/*
* Finally sanity check just to make sure we are not returning a negative index
*/
if(blk2->index < 0) {
state->inleaf = 1;
blk2->index = 0;
cmn_err(CE_ALERT,
"xfs_dir2_leafn_rebalance: picked the wrong leaf? reverting original leaf: "
"blk1->index %d\n",
blk1->index);
}
}
/*
* Remove an entry from a node directory.
* This removes the leaf entry and the data entry,
* and updates the free block if necessary.
*/
static int /* error */
xfs_dir2_leafn_remove(
xfs_da_args_t *args, /* operation arguments */
xfs_dabuf_t *bp, /* leaf buffer */
int index, /* leaf entry index */
xfs_da_state_blk_t *dblk, /* data block */
int *rval) /* resulting block needs join */
{
xfs_dir2_data_t *data; /* data block structure */
xfs_dir2_db_t db; /* data block number */
xfs_dabuf_t *dbp; /* data block buffer */
xfs_dir2_data_entry_t *dep; /* data block entry */
xfs_inode_t *dp; /* incore directory inode */
xfs_dir2_leaf_t *leaf; /* leaf structure */
xfs_dir2_leaf_entry_t *lep; /* leaf entry */
int longest; /* longest data free entry */
int off; /* data block entry offset */
xfs_mount_t *mp; /* filesystem mount point */
int needlog; /* need to log data header */
int needscan; /* need to rescan data frees */
xfs_trans_t *tp; /* transaction pointer */
xfs_dir2_trace_args_sb("leafn_remove", args, index, bp);
dp = args->dp;
tp = args->trans;
mp = dp->i_mount;
leaf = bp->data;
ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
/*
* Point to the entry we're removing.
*/
lep = &leaf->ents[index];
/*
* Extract the data block and offset from the entry.
*/
db = XFS_DIR2_DATAPTR_TO_DB(mp, be32_to_cpu(lep->address));
ASSERT(dblk->blkno == db);
off = XFS_DIR2_DATAPTR_TO_OFF(mp, be32_to_cpu(lep->address));
ASSERT(dblk->index == off);
/*
* Kill the leaf entry by marking it stale.
* Log the leaf block changes.
*/
be16_add(&leaf->hdr.stale, 1);
xfs_dir2_leaf_log_header(tp, bp);
lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
xfs_dir2_leaf_log_ents(tp, bp, index, index);
/*
* Make the data entry free. Keep track of the longest freespace
* in the data block in case it changes.
*/
dbp = dblk->bp;
data = dbp->data;
dep = (xfs_dir2_data_entry_t *)((char *)data + off);
longest = be16_to_cpu(data->hdr.bestfree[0].length);
needlog = needscan = 0;
xfs_dir2_data_make_free(tp, dbp, off,
XFS_DIR2_DATA_ENTSIZE(dep->namelen), &needlog, &needscan);
/*
* Rescan the data block freespaces for bestfree.
* Log the data block header if needed.
*/
if (needscan)
xfs_dir2_data_freescan(mp, data, &needlog, NULL);
if (needlog)
xfs_dir2_data_log_header(tp, dbp);
xfs_dir2_data_check(dp, dbp);
/*
* If the longest data block freespace changes, need to update
* the corresponding freeblock entry.
*/
if (longest < be16_to_cpu(data->hdr.bestfree[0].length)) {
int error; /* error return value */
xfs_dabuf_t *fbp; /* freeblock buffer */
xfs_dir2_db_t fdb; /* freeblock block number */
int findex; /* index in freeblock entries */
xfs_dir2_free_t *free; /* freeblock structure */
int logfree; /* need to log free entry */
/*
* Convert the data block number to a free block,
* read in the free block.
*/
fdb = XFS_DIR2_DB_TO_FDB(mp, db);
if ((error = xfs_da_read_buf(tp, dp, XFS_DIR2_DB_TO_DA(mp, fdb),
-1, &fbp, XFS_DATA_FORK))) {
return error;
}
free = fbp->data;
ASSERT(be32_to_cpu(free->hdr.magic) == XFS_DIR2_FREE_MAGIC);
ASSERT(be32_to_cpu(free->hdr.firstdb) ==
XFS_DIR2_MAX_FREE_BESTS(mp) *
(fdb - XFS_DIR2_FREE_FIRSTDB(mp)));
/*
* Calculate which entry we need to fix.
*/
findex = XFS_DIR2_DB_TO_FDINDEX(mp, db);
longest = be16_to_cpu(data->hdr.bestfree[0].length);
/*
* If the data block is now empty we can get rid of it
* (usually).
*/
if (longest == mp->m_dirblksize - (uint)sizeof(data->hdr)) {
/*
* Try to punch out the data block.
*/
error = xfs_dir2_shrink_inode(args, db, dbp);
if (error == 0) {
dblk->bp = NULL;
data = NULL;
}
/*
* We can get ENOSPC if there's no space reservation.
* In this case just drop the buffer and some one else
* will eventually get rid of the empty block.
*/
else if (error == ENOSPC && args->total == 0)
xfs_da_buf_done(dbp);
else
return error;
}
/*
* If we got rid of the data block, we can eliminate that entry
* in the free block.
*/
if (data == NULL) {
/*
* One less used entry in the free table.
*/
be32_add(&free->hdr.nused, -1);
xfs_dir2_free_log_header(tp, fbp);
/*
* If this was the last entry in the table, we can
* trim the table size back. There might be other
* entries at the end referring to non-existent
* data blocks, get those too.
*/
if (findex == be32_to_cpu(free->hdr.nvalid) - 1) {
int i; /* free entry index */
for (i = findex - 1;
i >= 0 && be16_to_cpu(free->bests[i]) == NULLDATAOFF;
i--)
continue;
free->hdr.nvalid = cpu_to_be32(i + 1);
logfree = 0;
}
/*
* Not the last entry, just punch it out.
*/
else {
free->bests[findex] = cpu_to_be16(NULLDATAOFF);
logfree = 1;
}
/*
* If there are no useful entries left in the block,
* get rid of the block if we can.