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Commit 687b890a authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Lachlan McIlroy
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[XFS] implement generic xfs_btree_lshift 

Make the btree left shift code generic. Based on a patch from David
Chinner with lots of changes to follow the original btree implementations
more closely. While this loses some of the generic helper routines for
inserting/moving/removing records it also solves some of the one off bugs
in the original code and makes it easier to verify.

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32197a
Signed-off-by: default avatarChristoph Hellwig <hch@infradead.org>
Signed-off-by: default avatarLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: default avatarBill O'Donnell <billodo@sgi.com>
Signed-off-by: default avatarDavid Chinner <david@fromorbit.com>
parent 9eaead51
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Showing with 192 additions and 425 deletions
fs/xfs/xfs_alloc_btree.c
View file @ 687b890a
......@@ -47,7 +47,6 @@ STATIC void xfs_alloc_log_block(xfs_trans_t *, xfs_buf_t *, int);
STATIC void xfs_alloc_log_keys(xfs_btree_cur_t *, xfs_buf_t *, int, int);
STATIC void xfs_alloc_log_ptrs(xfs_btree_cur_t *, xfs_buf_t *, int, int);
STATIC void xfs_alloc_log_recs(xfs_btree_cur_t *, xfs_buf_t *, int, int);
STATIC int xfs_alloc_lshift(xfs_btree_cur_t *, int, int *);
STATIC int xfs_alloc_newroot(xfs_btree_cur_t *, int *);
STATIC int xfs_alloc_split(xfs_btree_cur_t *, int, xfs_agblock_t *,
xfs_alloc_key_t *, xfs_btree_cur_t **, int *);
......@@ -326,7 +325,7 @@ xfs_alloc_delrec(
*/
if (be16_to_cpu(right->bb_numrecs) - 1 >=
XFS_ALLOC_BLOCK_MINRECS(level, cur)) {
if ((error = xfs_alloc_lshift(tcur, level, &i)))
if ((error = xfs_btree_lshift(tcur, level, &i)))
goto error0;
if (i) {
ASSERT(be16_to_cpu(block->bb_numrecs) >=
......@@ -691,7 +690,7 @@ xfs_alloc_insrec(
* Next, try shifting an entry to the left neighbor.
*/
else {
if ((error = xfs_alloc_lshift(cur, level, &i)))
if ((error = xfs_btree_lshift(cur, level, &i)))
return error;
if (i)
optr = ptr = cur->bc_ptrs[level];
......@@ -935,147 +934,6 @@ xfs_alloc_log_recs(
xfs_trans_log_buf(cur->bc_tp, bp, first, last);
}
/*
* Move 1 record left from cur/level if possible.
* Update cur to reflect the new path.
*/
STATIC int /* error */
xfs_alloc_lshift(
xfs_btree_cur_t *cur, /* btree cursor */
int level, /* level to shift record on */
int *stat) /* success/failure */
{
int error; /* error return value */
#ifdef DEBUG
int i; /* loop index */
#endif
xfs_alloc_key_t key; /* key value for leaf level upward */
xfs_buf_t *lbp; /* buffer for left neighbor block */
xfs_alloc_block_t *left; /* left neighbor btree block */
int nrec; /* new number of left block entries */
xfs_buf_t *rbp; /* buffer for right (current) block */
xfs_alloc_block_t *right; /* right (current) btree block */
xfs_alloc_key_t *rkp=NULL; /* key pointer for right block */
xfs_alloc_ptr_t *rpp=NULL; /* address pointer for right block */
xfs_alloc_rec_t *rrp=NULL; /* record pointer for right block */
/*
* Set up variables for this block as "right".
*/
rbp = cur->bc_bufs[level];
right = XFS_BUF_TO_ALLOC_BLOCK(rbp);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, right, level, rbp)))
return error;
#endif
/*
* If we've got no left sibling then we can't shift an entry left.
*/
if (be32_to_cpu(right->bb_leftsib) == NULLAGBLOCK) {
*stat = 0;
return 0;
}
/*
* If the cursor entry is the one that would be moved, don't
* do it... it's too complicated.
*/
if (cur->bc_ptrs[level] <= 1) {
*stat = 0;
return 0;
}
/*
* Set up the left neighbor as "left".
*/
if ((error = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, be32_to_cpu(right->bb_leftsib),
0, &lbp, XFS_ALLOC_BTREE_REF)))
return error;
left = XFS_BUF_TO_ALLOC_BLOCK(lbp);
if ((error = xfs_btree_check_sblock(cur, left, level, lbp)))
return error;
/*
* If it's full, it can't take another entry.
*/
if (be16_to_cpu(left->bb_numrecs) == XFS_ALLOC_BLOCK_MAXRECS(level, cur)) {
*stat = 0;
return 0;
}
nrec = be16_to_cpu(left->bb_numrecs) + 1;
/*
* If non-leaf, copy a key and a ptr to the left block.
*/
if (level > 0) {
xfs_alloc_key_t *lkp; /* key pointer for left block */
xfs_alloc_ptr_t *lpp; /* address pointer for left block */
lkp = XFS_ALLOC_KEY_ADDR(left, nrec, cur);
rkp = XFS_ALLOC_KEY_ADDR(right, 1, cur);
*lkp = *rkp;
xfs_alloc_log_keys(cur, lbp, nrec, nrec);
lpp = XFS_ALLOC_PTR_ADDR(left, nrec, cur);
rpp = XFS_ALLOC_PTR_ADDR(right, 1, cur);
#ifdef DEBUG
if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(*rpp), level)))
return error;
#endif
*lpp = *rpp;
xfs_alloc_log_ptrs(cur, lbp, nrec, nrec);
xfs_btree_check_key(cur->bc_btnum, lkp - 1, lkp);
}
/*
* If leaf, copy a record to the left block.
*/
else {
xfs_alloc_rec_t *lrp; /* record pointer for left block */
lrp = XFS_ALLOC_REC_ADDR(left, nrec, cur);
rrp = XFS_ALLOC_REC_ADDR(right, 1, cur);
*lrp = *rrp;
xfs_alloc_log_recs(cur, lbp, nrec, nrec);
xfs_btree_check_rec(cur->bc_btnum, lrp - 1, lrp);
}
/*
* Bump and log left's numrecs, decrement and log right's numrecs.
*/
be16_add_cpu(&left->bb_numrecs, 1);
xfs_alloc_log_block(cur->bc_tp, lbp, XFS_BB_NUMRECS);
be16_add_cpu(&right->bb_numrecs, -1);
xfs_alloc_log_block(cur->bc_tp, rbp, XFS_BB_NUMRECS);
/*
* Slide the contents of right down one entry.
*/
if (level > 0) {
#ifdef DEBUG
for (i = 0; i < be16_to_cpu(right->bb_numrecs); i++) {
if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(rpp[i + 1]),
level)))
return error;
}
#endif
memmove(rkp, rkp + 1, be16_to_cpu(right->bb_numrecs) * sizeof(*rkp));
memmove(rpp, rpp + 1, be16_to_cpu(right->bb_numrecs) * sizeof(*rpp));
xfs_alloc_log_keys(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
xfs_alloc_log_ptrs(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
} else {
memmove(rrp, rrp + 1, be16_to_cpu(right->bb_numrecs) * sizeof(*rrp));
xfs_alloc_log_recs(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
key.ar_startblock = rrp->ar_startblock;
key.ar_blockcount = rrp->ar_blockcount;
rkp = &key;
}
/*
* Update the parent key values of right.
*/
if ((error = xfs_btree_updkey(cur, (union xfs_btree_key *)rkp, level + 1)))
return error;
/*
* Slide the cursor value left one.
*/
cur->bc_ptrs[level]--;
*stat = 1;
return 0;
}
/*
* Allocate a new root block, fill it in.
*/
......
fs/xfs/xfs_bmap_btree.c
View file @ 687b890a
......@@ -52,7 +52,6 @@
STATIC int xfs_bmbt_killroot(xfs_btree_cur_t *);
STATIC void xfs_bmbt_log_keys(xfs_btree_cur_t *, xfs_buf_t *, int, int);
STATIC void xfs_bmbt_log_ptrs(xfs_btree_cur_t *, xfs_buf_t *, int, int);
STATIC int xfs_bmbt_lshift(xfs_btree_cur_t *, int, int *);
STATIC int xfs_bmbt_split(xfs_btree_cur_t *, int, xfs_fsblock_t *,
__uint64_t *, xfs_btree_cur_t **, int *);
......@@ -270,7 +269,7 @@ xfs_bmbt_delrec(
bno = be64_to_cpu(right->bb_leftsib);
if (be16_to_cpu(right->bb_numrecs) - 1 >=
XFS_BMAP_BLOCK_IMINRECS(level, cur)) {
if ((error = xfs_bmbt_lshift(tcur, level, &i))) {
if ((error = xfs_btree_lshift(tcur, level, &i))) {
XFS_BMBT_TRACE_CURSOR(cur, ERROR);
goto error0;
}
......@@ -544,7 +543,7 @@ xfs_bmbt_insrec(
if (i) {
/* nothing */
} else {
if ((error = xfs_bmbt_lshift(cur, level, &i))) {
if ((error = xfs_btree_lshift(cur, level, &i))) {
XFS_BMBT_TRACE_CURSOR(cur, ERROR);
return error;
}
......@@ -810,139 +809,6 @@ xfs_bmbt_log_ptrs(
XFS_BMBT_TRACE_CURSOR(cur, EXIT);
}
/*
* Move 1 record left from cur/level if possible.
* Update cur to reflect the new path.
*/
STATIC int /* error */
xfs_bmbt_lshift(
xfs_btree_cur_t *cur,
int level,
int *stat) /* success/failure */
{
int error; /* error return value */
#ifdef DEBUG
int i; /* loop counter */
#endif
xfs_bmbt_key_t key; /* bmap btree key */
xfs_buf_t *lbp; /* left buffer pointer */
xfs_bmbt_block_t *left; /* left btree block */
xfs_bmbt_key_t *lkp=NULL; /* left btree key */
xfs_bmbt_ptr_t *lpp; /* left address pointer */
int lrecs; /* left record count */
xfs_bmbt_rec_t *lrp=NULL; /* left record pointer */
xfs_mount_t *mp; /* file system mount point */
xfs_buf_t *rbp; /* right buffer pointer */
xfs_bmbt_block_t *right; /* right btree block */
xfs_bmbt_key_t *rkp=NULL; /* right btree key */
xfs_bmbt_ptr_t *rpp=NULL; /* right address pointer */
xfs_bmbt_rec_t *rrp=NULL; /* right record pointer */
int rrecs; /* right record count */
XFS_BMBT_TRACE_CURSOR(cur, ENTRY);
XFS_BMBT_TRACE_ARGI(cur, level);
if (level == cur->bc_nlevels - 1) {
XFS_BMBT_TRACE_CURSOR(cur, EXIT);
*stat = 0;
return 0;
}
rbp = cur->bc_bufs[level];
right = XFS_BUF_TO_BMBT_BLOCK(rbp);
#ifdef DEBUG
if ((error = xfs_btree_check_lblock(cur, right, level, rbp))) {
XFS_BMBT_TRACE_CURSOR(cur, ERROR);
return error;
}
#endif
if (be64_to_cpu(right->bb_leftsib) == NULLDFSBNO) {
XFS_BMBT_TRACE_CURSOR(cur, EXIT);
*stat = 0;
return 0;
}
if (cur->bc_ptrs[level] <= 1) {
XFS_BMBT_TRACE_CURSOR(cur, EXIT);
*stat = 0;
return 0;
}
mp = cur->bc_mp;
if ((error = xfs_btree_read_bufl(mp, cur->bc_tp, be64_to_cpu(right->bb_leftsib), 0,
&lbp, XFS_BMAP_BTREE_REF))) {
XFS_BMBT_TRACE_CURSOR(cur, ERROR);
return error;
}
left = XFS_BUF_TO_BMBT_BLOCK(lbp);
if ((error = xfs_btree_check_lblock(cur, left, level, lbp))) {
XFS_BMBT_TRACE_CURSOR(cur, ERROR);
return error;
}
if (be16_to_cpu(left->bb_numrecs) == XFS_BMAP_BLOCK_IMAXRECS(level, cur)) {
XFS_BMBT_TRACE_CURSOR(cur, EXIT);
*stat = 0;
return 0;
}
lrecs = be16_to_cpu(left->bb_numrecs) + 1;
if (level > 0) {
lkp = XFS_BMAP_KEY_IADDR(left, lrecs, cur);
rkp = XFS_BMAP_KEY_IADDR(right, 1, cur);
*lkp = *rkp;
xfs_bmbt_log_keys(cur, lbp, lrecs, lrecs);
lpp = XFS_BMAP_PTR_IADDR(left, lrecs, cur);
rpp = XFS_BMAP_PTR_IADDR(right, 1, cur);
#ifdef DEBUG
if ((error = xfs_btree_check_lptr_disk(cur, *rpp, level))) {
XFS_BMBT_TRACE_CURSOR(cur, ERROR);
return error;
}
#endif
*lpp = *rpp;
xfs_bmbt_log_ptrs(cur, lbp, lrecs, lrecs);
} else {
lrp = XFS_BMAP_REC_IADDR(left, lrecs, cur);
rrp = XFS_BMAP_REC_IADDR(right, 1, cur);
*lrp = *rrp;
xfs_bmbt_log_recs(cur, lbp, lrecs, lrecs);
}
left->bb_numrecs = cpu_to_be16(lrecs);
xfs_bmbt_log_block(cur, lbp, XFS_BB_NUMRECS);
#ifdef DEBUG
if (level > 0)
xfs_btree_check_key(XFS_BTNUM_BMAP, lkp - 1, lkp);
else
xfs_btree_check_rec(XFS_BTNUM_BMAP, lrp - 1, lrp);
#endif
rrecs = be16_to_cpu(right->bb_numrecs) - 1;
right->bb_numrecs = cpu_to_be16(rrecs);
xfs_bmbt_log_block(cur, rbp, XFS_BB_NUMRECS);
if (level > 0) {
#ifdef DEBUG
for (i = 0; i < rrecs; i++) {
if ((error = xfs_btree_check_lptr_disk(cur, rpp[i + 1],
level))) {
XFS_BMBT_TRACE_CURSOR(cur, ERROR);
return error;
}
}
#endif
memmove(rkp, rkp + 1, rrecs * sizeof(*rkp));
memmove(rpp, rpp + 1, rrecs * sizeof(*rpp));
xfs_bmbt_log_keys(cur, rbp, 1, rrecs);
xfs_bmbt_log_ptrs(cur, rbp, 1, rrecs);
} else {
memmove(rrp, rrp + 1, rrecs * sizeof(*rrp));
xfs_bmbt_log_recs(cur, rbp, 1, rrecs);
key.br_startoff = cpu_to_be64(xfs_bmbt_disk_get_startoff(rrp));
rkp = &key;
}
if ((error = xfs_btree_updkey(cur, (union xfs_btree_key *)rkp, level + 1))) {
XFS_BMBT_TRACE_CURSOR(cur, ERROR);
return error;
}
cur->bc_ptrs[level]--;
XFS_BMBT_TRACE_CURSOR(cur, EXIT);
*stat = 1;
return 0;
}
/*
* Determine the extent state.
*/
......
fs/xfs/xfs_btree.c
View file @ 687b890a
......@@ -1840,6 +1840,191 @@ xfs_btree_update(
return error;
}
/*
* Move 1 record left from cur/level if possible.
* Update cur to reflect the new path.
*/
int /* error */
xfs_btree_lshift(
struct xfs_btree_cur *cur,
int level,
int *stat) /* success/failure */
{
union xfs_btree_key key; /* btree key */
struct xfs_buf *lbp; /* left buffer pointer */
struct xfs_btree_block *left; /* left btree block */
int lrecs; /* left record count */
struct xfs_buf *rbp; /* right buffer pointer */
struct xfs_btree_block *right; /* right btree block */
int rrecs; /* right record count */
union xfs_btree_ptr lptr; /* left btree pointer */
union xfs_btree_key *rkp = NULL; /* right btree key */
union xfs_btree_ptr *rpp = NULL; /* right address pointer */
union xfs_btree_rec *rrp = NULL; /* right record pointer */
int error; /* error return value */
XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
XFS_BTREE_TRACE_ARGI(cur, level);
if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
level == cur->bc_nlevels - 1)
goto out0;
/* Set up variables for this block as "right". */
right = xfs_btree_get_block(cur, level, &rbp);
#ifdef DEBUG
error = xfs_btree_check_block(cur, right, level, rbp);
if (error)
goto error0;
#endif
/* If we've got no left sibling then we can't shift an entry left. */
xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
if (xfs_btree_ptr_is_null(cur, &lptr))
goto out0;
/*
* If the cursor entry is the one that would be moved, don't
* do it... it's too complicated.
*/
if (cur->bc_ptrs[level] <= 1)
goto out0;
/* Set up the left neighbor as "left". */
error = xfs_btree_read_buf_block(cur, &lptr, level, 0, &left, &lbp);
if (error)
goto error0;
/* If it's full, it can't take another entry. */
lrecs = xfs_btree_get_numrecs(left);
if (lrecs == cur->bc_ops->get_maxrecs(cur, level))
goto out0;
rrecs = xfs_btree_get_numrecs(right);
/*
* We add one entry to the left side and remove one for the right side.
* Accout for it here, the changes will be updated on disk and logged
* later.
*/
lrecs++;
rrecs--;
XFS_BTREE_STATS_INC(cur, lshift);
XFS_BTREE_STATS_ADD(cur, moves, 1);
/*
* If non-leaf, copy a key and a ptr to the left block.
* Log the changes to the left block.
*/
if (level > 0) {
/* It's a non-leaf. Move keys and pointers. */
union xfs_btree_key *lkp; /* left btree key */
union xfs_btree_ptr *lpp; /* left address pointer */
lkp = xfs_btree_key_addr(cur, lrecs, left);
rkp = xfs_btree_key_addr(cur, 1, right);
lpp = xfs_btree_ptr_addr(cur, lrecs, left);
rpp = xfs_btree_ptr_addr(cur, 1, right);
#ifdef DEBUG
error = xfs_btree_check_ptr(cur, rpp, 0, level);
if (error)
goto error0;
#endif
xfs_btree_copy_keys(cur, lkp, rkp, 1);
xfs_btree_copy_ptrs(cur, lpp, rpp, 1);
xfs_btree_log_keys(cur, lbp, lrecs, lrecs);
xfs_btree_log_ptrs(cur, lbp, lrecs, lrecs);
xfs_btree_check_key(cur->bc_btnum,
xfs_btree_key_addr(cur, lrecs - 1, left),
lkp);
} else {
/* It's a leaf. Move records. */
union xfs_btree_rec *lrp; /* left record pointer */
lrp = xfs_btree_rec_addr(cur, lrecs, left);
rrp = xfs_btree_rec_addr(cur, 1, right);
xfs_btree_copy_recs(cur, lrp, rrp, 1);
xfs_btree_log_recs(cur, lbp, lrecs, lrecs);
xfs_btree_check_rec(cur->bc_btnum,
xfs_btree_rec_addr(cur, lrecs - 1, left),
lrp);
}
xfs_btree_set_numrecs(left, lrecs);
xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS);
xfs_btree_set_numrecs(right, rrecs);
xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS);
/*
* Slide the contents of right down one entry.
*/
XFS_BTREE_STATS_ADD(cur, moves, rrecs - 1);
if (level > 0) {
/* It's a nonleaf. operate on keys and ptrs */
#ifdef DEBUG
int i; /* loop index */
for (i = 0; i < rrecs; i++) {
error = xfs_btree_check_ptr(cur, rpp, i + 1, level);
if (error)
goto error0;
}
#endif
xfs_btree_shift_keys(cur,
xfs_btree_key_addr(cur, 2, right),
-1, rrecs);
xfs_btree_shift_ptrs(cur,
xfs_btree_ptr_addr(cur, 2, right),
-1, rrecs);
xfs_btree_log_keys(cur, rbp, 1, rrecs);
xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
} else {
/* It's a leaf. operate on records */
xfs_btree_shift_recs(cur,
xfs_btree_rec_addr(cur, 2, right),
-1, rrecs);
xfs_btree_log_recs(cur, rbp, 1, rrecs);
/*
* If it's the first record in the block, we'll need a key
* structure to pass up to the next level (updkey).
*/
cur->bc_ops->init_key_from_rec(&key,
xfs_btree_rec_addr(cur, 1, right));
rkp = &key;
}
/* Update the parent key values of right. */
error = xfs_btree_updkey(cur, rkp, level + 1);
if (error)
goto error0;
/* Slide the cursor value left one. */
cur->bc_ptrs[level]--;
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
*stat = 1;
return 0;
out0:
XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
*stat = 0;
return 0;
error0:
XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
return error;
}
/*
* Move 1 record right from cur/level if possible.
* Update cur to reflect the new path.
......
fs/xfs/xfs_btree.h
View file @ 687b890a
......@@ -533,6 +533,7 @@ int xfs_btree_decrement(struct xfs_btree_cur *, int, int *);
int xfs_btree_lookup(struct xfs_btree_cur *, xfs_lookup_t, int *);
int xfs_btree_updkey(struct xfs_btree_cur *, union xfs_btree_key *, int);
int xfs_btree_update(struct xfs_btree_cur *, union xfs_btree_rec *);
int xfs_btree_lshift(struct xfs_btree_cur *, int, int *);
int xfs_btree_rshift(struct xfs_btree_cur *, int, int *);
/*
......
fs/xfs/xfs_ialloc_btree.c
View file @ 687b890a
......@@ -43,7 +43,6 @@ STATIC void xfs_inobt_log_block(xfs_trans_t *, xfs_buf_t *, int);
STATIC void xfs_inobt_log_keys(xfs_btree_cur_t *, xfs_buf_t *, int, int);
STATIC void xfs_inobt_log_ptrs(xfs_btree_cur_t *, xfs_buf_t *, int, int);
STATIC void xfs_inobt_log_recs(xfs_btree_cur_t *, xfs_buf_t *, int, int);
STATIC int xfs_inobt_lshift(xfs_btree_cur_t *, int, int *);
STATIC int xfs_inobt_newroot(xfs_btree_cur_t *, int *);
STATIC int xfs_inobt_split(xfs_btree_cur_t *, int, xfs_agblock_t *,
xfs_inobt_key_t *, xfs_btree_cur_t **, int *);
......@@ -276,7 +275,7 @@ xfs_inobt_delrec(
*/
if (be16_to_cpu(right->bb_numrecs) - 1 >=
XFS_INOBT_BLOCK_MINRECS(level, cur)) {
if ((error = xfs_inobt_lshift(tcur, level, &i)))
if ((error = xfs_btree_lshift(tcur, level, &i)))
goto error0;
if (i) {
ASSERT(be16_to_cpu(block->bb_numrecs) >=
......@@ -616,7 +615,7 @@ xfs_inobt_insrec(
* Next, try shifting an entry to the left neighbor.
*/
else {
if ((error = xfs_inobt_lshift(cur, level, &i)))
if ((error = xfs_btree_lshift(cur, level, &i)))
return error;
if (i) {
optr = ptr = cur->bc_ptrs[level];
......@@ -826,148 +825,6 @@ xfs_inobt_log_recs(
xfs_trans_log_buf(cur->bc_tp, bp, first, last);
}
/*
* Move 1 record left from cur/level if possible.
* Update cur to reflect the new path.
*/
STATIC int /* error */
xfs_inobt_lshift(
xfs_btree_cur_t *cur, /* btree cursor */
int level, /* level to shift record on */
int *stat) /* success/failure */
{
int error; /* error return value */
#ifdef DEBUG
int i; /* loop index */
#endif
xfs_inobt_key_t key; /* key value for leaf level upward */
xfs_buf_t *lbp; /* buffer for left neighbor block */
xfs_inobt_block_t *left; /* left neighbor btree block */
xfs_inobt_key_t *lkp=NULL; /* key pointer for left block */
xfs_inobt_ptr_t *lpp; /* address pointer for left block */
xfs_inobt_rec_t *lrp=NULL; /* record pointer for left block */
int nrec; /* new number of left block entries */
xfs_buf_t *rbp; /* buffer for right (current) block */
xfs_inobt_block_t *right; /* right (current) btree block */
xfs_inobt_key_t *rkp=NULL; /* key pointer for right block */
xfs_inobt_ptr_t *rpp=NULL; /* address pointer for right block */
xfs_inobt_rec_t *rrp=NULL; /* record pointer for right block */
/*
* Set up variables for this block as "right".
*/
rbp = cur->bc_bufs[level];
right = XFS_BUF_TO_INOBT_BLOCK(rbp);
#ifdef DEBUG
if ((error = xfs_btree_check_sblock(cur, right, level, rbp)))
return error;
#endif
/*
* If we've got no left sibling then we can't shift an entry left.
*/
if (be32_to_cpu(right->bb_leftsib) == NULLAGBLOCK) {
*stat = 0;
return 0;
}
/*
* If the cursor entry is the one that would be moved, don't
* do it... it's too complicated.
*/
if (cur->bc_ptrs[level] <= 1) {
*stat = 0;
return 0;
}
/*
* Set up the left neighbor as "left".
*/
if ((error = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
cur->bc_private.a.agno, be32_to_cpu(right->bb_leftsib),
0, &lbp, XFS_INO_BTREE_REF)))
return error;
left = XFS_BUF_TO_INOBT_BLOCK(lbp);
if ((error = xfs_btree_check_sblock(cur, left, level, lbp)))
return error;
/*
* If it's full, it can't take another entry.
*/
if (be16_to_cpu(left->bb_numrecs) == XFS_INOBT_BLOCK_MAXRECS(level, cur)) {
*stat = 0;
return 0;
}
nrec = be16_to_cpu(left->bb_numrecs) + 1;
/*
* If non-leaf, copy a key and a ptr to the left block.
*/
if (level > 0) {
lkp = XFS_INOBT_KEY_ADDR(left, nrec, cur);
rkp = XFS_INOBT_KEY_ADDR(right, 1, cur);
*lkp = *rkp;
xfs_inobt_log_keys(cur, lbp, nrec, nrec);
lpp = XFS_INOBT_PTR_ADDR(left, nrec, cur);
rpp = XFS_INOBT_PTR_ADDR(right, 1, cur);
#ifdef DEBUG
if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(*rpp), level)))
return error;
#endif
*lpp = *rpp;
xfs_inobt_log_ptrs(cur, lbp, nrec, nrec);
}
/*
* If leaf, copy a record to the left block.
*/
else {
lrp = XFS_INOBT_REC_ADDR(left, nrec, cur);
rrp = XFS_INOBT_REC_ADDR(right, 1, cur);
*lrp = *rrp;
xfs_inobt_log_recs(cur, lbp, nrec, nrec);
}
/*
* Bump and log left's numrecs, decrement and log right's numrecs.
*/
be16_add_cpu(&left->bb_numrecs, 1);
xfs_inobt_log_block(cur->bc_tp, lbp, XFS_BB_NUMRECS);
#ifdef DEBUG
if (level > 0)
xfs_btree_check_key(cur->bc_btnum, lkp - 1, lkp);
else
xfs_btree_check_rec(cur->bc_btnum, lrp - 1, lrp);
#endif
be16_add_cpu(&right->bb_numrecs, -1);
xfs_inobt_log_block(cur->bc_tp, rbp, XFS_BB_NUMRECS);
/*
* Slide the contents of right down one entry.
*/
if (level > 0) {
#ifdef DEBUG
for (i = 0; i < be16_to_cpu(right->bb_numrecs); i++) {
if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(rpp[i + 1]),
level)))
return error;
}
#endif
memmove(rkp, rkp + 1, be16_to_cpu(right->bb_numrecs) * sizeof(*rkp));
memmove(rpp, rpp + 1, be16_to_cpu(right->bb_numrecs) * sizeof(*rpp));
xfs_inobt_log_keys(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
xfs_inobt_log_ptrs(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
} else {
memmove(rrp, rrp + 1, be16_to_cpu(right->bb_numrecs) * sizeof(*rrp));
xfs_inobt_log_recs(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
key.ir_startino = rrp->ir_startino;
rkp = &key;
}
/*
* Update the parent key values of right.
*/
if ((error = xfs_btree_updkey(cur, (union xfs_btree_key *)rkp, level + 1)))
return error;
/*
* Slide the cursor value left one.
*/
cur->bc_ptrs[level]--;
*stat = 1;
return 0;
}
/*
* Allocate a new root block, fill it in.
*/
......
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