#include "xfs_attr_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
+#include "xfs_inode_item.h"
#include "xfs_btree.h"
+#include "xfs_btree_trace.h"
#include "xfs_ialloc.h"
#include "xfs_error.h"
+#include "xfs_trace.h"
/*
* Cursor allocation zone.
XFS_ABTB_MAGIC, XFS_ABTC_MAGIC, XFS_BMAP_MAGIC, XFS_IBT_MAGIC
};
-/*
- * Checking routine: return maxrecs for the block.
- */
-STATIC int /* number of records fitting in block */
-xfs_btree_maxrecs(
- xfs_btree_cur_t *cur, /* btree cursor */
- xfs_btree_block_t *block) /* generic btree block pointer */
-{
- switch (cur->bc_btnum) {
- case XFS_BTNUM_BNO:
- case XFS_BTNUM_CNT:
- return (int)XFS_ALLOC_BLOCK_MAXRECS(
- be16_to_cpu(block->bb_level), cur);
- case XFS_BTNUM_BMAP:
- return (int)XFS_BMAP_BLOCK_IMAXRECS(
- be16_to_cpu(block->bb_level), cur);
- case XFS_BTNUM_INO:
- return (int)XFS_INOBT_BLOCK_MAXRECS(
- be16_to_cpu(block->bb_level), cur);
- default:
- ASSERT(0);
- return 0;
- }
-}
-
-/*
- * External routines.
- */
-
-#ifdef DEBUG
-/*
- * Debug routine: check that keys are in the right order.
- */
-void
-xfs_btree_check_key(
- xfs_btnum_t btnum, /* btree identifier */
- void *ak1, /* pointer to left (lower) key */
- void *ak2) /* pointer to right (higher) key */
-{
- switch (btnum) {
- case XFS_BTNUM_BNO: {
- xfs_alloc_key_t *k1;
- xfs_alloc_key_t *k2;
-
- k1 = ak1;
- k2 = ak2;
- ASSERT(be32_to_cpu(k1->ar_startblock) < be32_to_cpu(k2->ar_startblock));
- break;
- }
- case XFS_BTNUM_CNT: {
- xfs_alloc_key_t *k1;
- xfs_alloc_key_t *k2;
-
- k1 = ak1;
- k2 = ak2;
- ASSERT(be32_to_cpu(k1->ar_blockcount) < be32_to_cpu(k2->ar_blockcount) ||
- (k1->ar_blockcount == k2->ar_blockcount &&
- be32_to_cpu(k1->ar_startblock) < be32_to_cpu(k2->ar_startblock)));
- break;
- }
- case XFS_BTNUM_BMAP: {
- xfs_bmbt_key_t *k1;
- xfs_bmbt_key_t *k2;
-
- k1 = ak1;
- k2 = ak2;
- ASSERT(be64_to_cpu(k1->br_startoff) < be64_to_cpu(k2->br_startoff));
- break;
- }
- case XFS_BTNUM_INO: {
- xfs_inobt_key_t *k1;
- xfs_inobt_key_t *k2;
-
- k1 = ak1;
- k2 = ak2;
- ASSERT(be32_to_cpu(k1->ir_startino) < be32_to_cpu(k2->ir_startino));
- break;
- }
- default:
- ASSERT(0);
- }
-}
-
-/*
- * Debug routine: check that records are in the right order.
- */
-void
-xfs_btree_check_rec(
- xfs_btnum_t btnum, /* btree identifier */
- void *ar1, /* pointer to left (lower) record */
- void *ar2) /* pointer to right (higher) record */
-{
- switch (btnum) {
- case XFS_BTNUM_BNO: {
- xfs_alloc_rec_t *r1;
- xfs_alloc_rec_t *r2;
-
- r1 = ar1;
- r2 = ar2;
- ASSERT(be32_to_cpu(r1->ar_startblock) +
- be32_to_cpu(r1->ar_blockcount) <=
- be32_to_cpu(r2->ar_startblock));
- break;
- }
- case XFS_BTNUM_CNT: {
- xfs_alloc_rec_t *r1;
- xfs_alloc_rec_t *r2;
-
- r1 = ar1;
- r2 = ar2;
- ASSERT(be32_to_cpu(r1->ar_blockcount) < be32_to_cpu(r2->ar_blockcount) ||
- (r1->ar_blockcount == r2->ar_blockcount &&
- be32_to_cpu(r1->ar_startblock) < be32_to_cpu(r2->ar_startblock)));
- break;
- }
- case XFS_BTNUM_BMAP: {
- xfs_bmbt_rec_t *r1;
- xfs_bmbt_rec_t *r2;
-
- r1 = ar1;
- r2 = ar2;
- ASSERT(xfs_bmbt_disk_get_startoff(r1) +
- xfs_bmbt_disk_get_blockcount(r1) <=
- xfs_bmbt_disk_get_startoff(r2));
- break;
- }
- case XFS_BTNUM_INO: {
- xfs_inobt_rec_t *r1;
- xfs_inobt_rec_t *r2;
-
- r1 = ar1;
- r2 = ar2;
- ASSERT(be32_to_cpu(r1->ir_startino) + XFS_INODES_PER_CHUNK <=
- be32_to_cpu(r2->ir_startino));
- break;
- }
- default:
- ASSERT(0);
- }
-}
-#endif /* DEBUG */
-int /* error (0 or EFSCORRUPTED) */
+STATIC int /* error (0 or EFSCORRUPTED) */
xfs_btree_check_lblock(
struct xfs_btree_cur *cur, /* btree cursor */
- struct xfs_btree_lblock *block, /* btree long form block pointer */
+ struct xfs_btree_block *block, /* btree long form block pointer */
int level, /* level of the btree block */
struct xfs_buf *bp) /* buffer for block, if any */
{
be32_to_cpu(block->bb_magic) == xfs_magics[cur->bc_btnum] &&
be16_to_cpu(block->bb_level) == level &&
be16_to_cpu(block->bb_numrecs) <=
- xfs_btree_maxrecs(cur, (xfs_btree_block_t *)block) &&
- block->bb_leftsib &&
- (be64_to_cpu(block->bb_leftsib) == NULLDFSBNO ||
- XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_leftsib))) &&
- block->bb_rightsib &&
- (be64_to_cpu(block->bb_rightsib) == NULLDFSBNO ||
- XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_rightsib)));
+ cur->bc_ops->get_maxrecs(cur, level) &&
+ block->bb_u.l.bb_leftsib &&
+ (be64_to_cpu(block->bb_u.l.bb_leftsib) == NULLDFSBNO ||
+ XFS_FSB_SANITY_CHECK(mp,
+ be64_to_cpu(block->bb_u.l.bb_leftsib))) &&
+ block->bb_u.l.bb_rightsib &&
+ (be64_to_cpu(block->bb_u.l.bb_rightsib) == NULLDFSBNO ||
+ XFS_FSB_SANITY_CHECK(mp,
+ be64_to_cpu(block->bb_u.l.bb_rightsib)));
if (unlikely(XFS_TEST_ERROR(!lblock_ok, mp,
XFS_ERRTAG_BTREE_CHECK_LBLOCK,
XFS_RANDOM_BTREE_CHECK_LBLOCK))) {
if (bp)
- xfs_buftrace("LBTREE ERROR", bp);
+ trace_xfs_btree_corrupt(bp, _RET_IP_);
XFS_ERROR_REPORT("xfs_btree_check_lblock", XFS_ERRLEVEL_LOW,
mp);
return XFS_ERROR(EFSCORRUPTED);
return 0;
}
-int /* error (0 or EFSCORRUPTED) */
+STATIC int /* error (0 or EFSCORRUPTED) */
xfs_btree_check_sblock(
struct xfs_btree_cur *cur, /* btree cursor */
- struct xfs_btree_sblock *block, /* btree short form block pointer */
+ struct xfs_btree_block *block, /* btree short form block pointer */
int level, /* level of the btree block */
struct xfs_buf *bp) /* buffer containing block */
{
be32_to_cpu(block->bb_magic) == xfs_magics[cur->bc_btnum] &&
be16_to_cpu(block->bb_level) == level &&
be16_to_cpu(block->bb_numrecs) <=
- xfs_btree_maxrecs(cur, (xfs_btree_block_t *)block) &&
- (be32_to_cpu(block->bb_leftsib) == NULLAGBLOCK ||
- be32_to_cpu(block->bb_leftsib) < agflen) &&
- block->bb_leftsib &&
- (be32_to_cpu(block->bb_rightsib) == NULLAGBLOCK ||
- be32_to_cpu(block->bb_rightsib) < agflen) &&
- block->bb_rightsib;
+ cur->bc_ops->get_maxrecs(cur, level) &&
+ (be32_to_cpu(block->bb_u.s.bb_leftsib) == NULLAGBLOCK ||
+ be32_to_cpu(block->bb_u.s.bb_leftsib) < agflen) &&
+ block->bb_u.s.bb_leftsib &&
+ (be32_to_cpu(block->bb_u.s.bb_rightsib) == NULLAGBLOCK ||
+ be32_to_cpu(block->bb_u.s.bb_rightsib) < agflen) &&
+ block->bb_u.s.bb_rightsib;
if (unlikely(XFS_TEST_ERROR(!sblock_ok, cur->bc_mp,
XFS_ERRTAG_BTREE_CHECK_SBLOCK,
XFS_RANDOM_BTREE_CHECK_SBLOCK))) {
if (bp)
- xfs_buftrace("SBTREE ERROR", bp);
- XFS_ERROR_REPORT("xfs_btree_check_sblock", XFS_ERRLEVEL_LOW,
- cur->bc_mp);
+ trace_xfs_btree_corrupt(bp, _RET_IP_);
+ XFS_CORRUPTION_ERROR("xfs_btree_check_sblock",
+ XFS_ERRLEVEL_LOW, cur->bc_mp, block);
return XFS_ERROR(EFSCORRUPTED);
}
return 0;
int level, /* level of the btree block */
struct xfs_buf *bp) /* buffer containing block, if any */
{
- if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
- return xfs_btree_check_lblock(cur,
- (struct xfs_btree_lblock *)block, level, bp);
- } else {
- return xfs_btree_check_sblock(cur,
- (struct xfs_btree_sblock *)block, level, bp);
- }
+ if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
+ return xfs_btree_check_lblock(cur, block, level, bp);
+ else
+ return xfs_btree_check_sblock(cur, block, level, bp);
}
/*
return 0;
}
+#ifdef DEBUG
/*
* Check that (short) pointer is ok.
*/
-int /* error (0 or EFSCORRUPTED) */
+STATIC int /* error (0 or EFSCORRUPTED) */
xfs_btree_check_sptr(
struct xfs_btree_cur *cur, /* btree cursor */
xfs_agblock_t bno, /* btree block disk address */
/*
* Check that block ptr is ok.
*/
-int /* error (0 or EFSCORRUPTED) */
+STATIC int /* error (0 or EFSCORRUPTED) */
xfs_btree_check_ptr(
struct xfs_btree_cur *cur, /* btree cursor */
union xfs_btree_ptr *ptr, /* btree block disk address */
be32_to_cpu((&ptr->s)[index]), level);
}
}
+#endif
/*
* Delete the btree cursor.
}
/*
+ * XFS btree block layout and addressing:
+ *
+ * There are two types of blocks in the btree: leaf and non-leaf blocks.
+ *
+ * The leaf record start with a header then followed by records containing
+ * the values. A non-leaf block also starts with the same header, and
+ * then first contains lookup keys followed by an equal number of pointers
+ * to the btree blocks at the previous level.
+ *
+ * +--------+-------+-------+-------+-------+-------+-------+
+ * Leaf: | header | rec 1 | rec 2 | rec 3 | rec 4 | rec 5 | rec N |
+ * +--------+-------+-------+-------+-------+-------+-------+
+ *
+ * +--------+-------+-------+-------+-------+-------+-------+
+ * Non-Leaf: | header | key 1 | key 2 | key N | ptr 1 | ptr 2 | ptr N |
+ * +--------+-------+-------+-------+-------+-------+-------+
+ *
+ * The header is called struct xfs_btree_block for reasons better left unknown
+ * and comes in different versions for short (32bit) and long (64bit) block
+ * pointers. The record and key structures are defined by the btree instances
+ * and opaque to the btree core. The block pointers are simple disk endian
+ * integers, available in a short (32bit) and long (64bit) variant.
+ *
+ * The helpers below calculate the offset of a given record, key or pointer
+ * into a btree block (xfs_btree_*_offset) or return a pointer to the given
+ * record, key or pointer (xfs_btree_*_addr). Note that all addressing
+ * inside the btree block is done using indices starting at one, not zero!
+ */
+
+/*
+ * Return size of the btree block header for this btree instance.
+ */
+static inline size_t xfs_btree_block_len(struct xfs_btree_cur *cur)
+{
+ return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
+ XFS_BTREE_LBLOCK_LEN :
+ XFS_BTREE_SBLOCK_LEN;
+}
+
+/*
+ * Return size of btree block pointers for this btree instance.
+ */
+static inline size_t xfs_btree_ptr_len(struct xfs_btree_cur *cur)
+{
+ return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
+ sizeof(__be64) : sizeof(__be32);
+}
+
+/*
+ * Calculate offset of the n-th record in a btree block.
+ */
+STATIC size_t
+xfs_btree_rec_offset(
+ struct xfs_btree_cur *cur,
+ int n)
+{
+ return xfs_btree_block_len(cur) +
+ (n - 1) * cur->bc_ops->rec_len;
+}
+
+/*
+ * Calculate offset of the n-th key in a btree block.
+ */
+STATIC size_t
+xfs_btree_key_offset(
+ struct xfs_btree_cur *cur,
+ int n)
+{
+ return xfs_btree_block_len(cur) +
+ (n - 1) * cur->bc_ops->key_len;
+}
+
+/*
+ * Calculate offset of the n-th block pointer in a btree block.
+ */
+STATIC size_t
+xfs_btree_ptr_offset(
+ struct xfs_btree_cur *cur,
+ int n,
+ int level)
+{
+ return xfs_btree_block_len(cur) +
+ cur->bc_ops->get_maxrecs(cur, level) * cur->bc_ops->key_len +
+ (n - 1) * xfs_btree_ptr_len(cur);
+}
+
+/*
+ * Return a pointer to the n-th record in the btree block.
+ */
+STATIC union xfs_btree_rec *
+xfs_btree_rec_addr(
+ struct xfs_btree_cur *cur,
+ int n,
+ struct xfs_btree_block *block)
+{
+ return (union xfs_btree_rec *)
+ ((char *)block + xfs_btree_rec_offset(cur, n));
+}
+
+/*
+ * Return a pointer to the n-th key in the btree block.
+ */
+STATIC union xfs_btree_key *
+xfs_btree_key_addr(
+ struct xfs_btree_cur *cur,
+ int n,
+ struct xfs_btree_block *block)
+{
+ return (union xfs_btree_key *)
+ ((char *)block + xfs_btree_key_offset(cur, n));
+}
+
+/*
+ * Return a pointer to the n-th block pointer in the btree block.
+ */
+STATIC union xfs_btree_ptr *
+xfs_btree_ptr_addr(
+ struct xfs_btree_cur *cur,
+ int n,
+ struct xfs_btree_block *block)
+{
+ int level = xfs_btree_get_level(block);
+
+ ASSERT(block->bb_level != 0);
+
+ return (union xfs_btree_ptr *)
+ ((char *)block + xfs_btree_ptr_offset(cur, n, level));
+}
+
+/*
* Get a the root block which is stored in the inode.
*
* For now this btree implementation assumes the btree root is always
xfs_btree_cur_t *cur, /* btree cursor */
int level) /* level to check */
{
- xfs_btree_block_t *block; /* generic btree block pointer */
+ struct xfs_btree_block *block; /* generic btree block pointer */
xfs_buf_t *bp; /* buffer containing block */
block = xfs_btree_get_block(cur, level, &bp);
* Change the cursor to point to the first record at the given level.
* Other levels are unaffected.
*/
-int /* success=1, failure=0 */
+STATIC int /* success=1, failure=0 */
xfs_btree_firstrec(
xfs_btree_cur_t *cur, /* btree cursor */
int level) /* level to change */
{
- xfs_btree_block_t *block; /* generic btree block pointer */
+ struct xfs_btree_block *block; /* generic btree block pointer */
xfs_buf_t *bp; /* buffer containing block */
/*
* Change the cursor to point to the last record in the current block
* at the given level. Other levels are unaffected.
*/
-int /* success=1, failure=0 */
+STATIC int /* success=1, failure=0 */
xfs_btree_lastrec(
xfs_btree_cur_t *cur, /* btree cursor */
int level) /* level to change */
{
- xfs_btree_block_t *block; /* generic btree block pointer */
+ struct xfs_btree_block *block; /* generic btree block pointer */
xfs_buf_t *bp; /* buffer containing block */
/*
}
/*
- * Get a buffer for the block, return it read in.
- * Short-form addressing.
- */
-int /* error */
-xfs_btree_read_bufs(
- xfs_mount_t *mp, /* file system mount point */
- xfs_trans_t *tp, /* transaction pointer */
- xfs_agnumber_t agno, /* allocation group number */
- xfs_agblock_t agbno, /* allocation group block number */
- uint lock, /* lock flags for read_buf */
- xfs_buf_t **bpp, /* buffer for agno/agbno */
- int refval) /* ref count value for buffer */
-{
- xfs_buf_t *bp; /* return value */
- xfs_daddr_t d; /* real disk block address */
- int error;
-
- ASSERT(agno != NULLAGNUMBER);
- ASSERT(agbno != NULLAGBLOCK);
- d = XFS_AGB_TO_DADDR(mp, agno, agbno);
- if ((error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, d,
- mp->m_bsize, lock, &bp))) {
- return error;
- }
- ASSERT(!bp || !XFS_BUF_GETERROR(bp));
- if (bp != NULL) {
- switch (refval) {
- case XFS_ALLOC_BTREE_REF:
- XFS_BUF_SET_VTYPE_REF(bp, B_FS_MAP, refval);
- break;
- case XFS_INO_BTREE_REF:
- XFS_BUF_SET_VTYPE_REF(bp, B_FS_INOMAP, refval);
- break;
- }
- }
- *bpp = bp;
- return 0;
-}
-
-/*
* Read-ahead the block, don't wait for it, don't return a buffer.
* Long-form addressing.
*/
struct xfs_btree_block *block)
{
int rval = 0;
- xfs_fsblock_t left = be64_to_cpu(block->bb_u.l.bb_leftsib);
- xfs_fsblock_t right = be64_to_cpu(block->bb_u.l.bb_rightsib);
+ xfs_dfsbno_t left = be64_to_cpu(block->bb_u.l.bb_leftsib);
+ xfs_dfsbno_t right = be64_to_cpu(block->bb_u.l.bb_rightsib);
if ((lr & XFS_BTCUR_LEFTRA) && left != NULLDFSBNO) {
xfs_btree_reada_bufl(cur->bc_mp, left, 1);
* Read-ahead btree blocks, at the given level.
* Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA.
*/
-int
+STATIC int
xfs_btree_readahead(
struct xfs_btree_cur *cur, /* btree cursor */
int lev, /* level in btree */
int lev, /* level in btree */
xfs_buf_t *bp) /* new buffer to set */
{
- xfs_btree_block_t *b; /* btree block */
+ struct xfs_btree_block *b; /* btree block */
xfs_buf_t *obp; /* old buffer pointer */
obp = cur->bc_bufs[lev];
cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
}
}
+
+STATIC int
+xfs_btree_ptr_is_null(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_ptr *ptr)
+{
+ if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
+ return be64_to_cpu(ptr->l) == NULLDFSBNO;
+ else
+ return be32_to_cpu(ptr->s) == NULLAGBLOCK;
+}
+
+STATIC void
+xfs_btree_set_ptr_null(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_ptr *ptr)
+{
+ if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
+ ptr->l = cpu_to_be64(NULLDFSBNO);
+ else
+ ptr->s = cpu_to_be32(NULLAGBLOCK);
+}
+
+/*
+ * Get/set/init sibling pointers
+ */
+STATIC void
+xfs_btree_get_sibling(
+ struct xfs_btree_cur *cur,
+ struct xfs_btree_block *block,
+ union xfs_btree_ptr *ptr,
+ int lr)
+{
+ ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
+
+ if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
+ if (lr == XFS_BB_RIGHTSIB)
+ ptr->l = block->bb_u.l.bb_rightsib;
+ else
+ ptr->l = block->bb_u.l.bb_leftsib;
+ } else {
+ if (lr == XFS_BB_RIGHTSIB)
+ ptr->s = block->bb_u.s.bb_rightsib;
+ else
+ ptr->s = block->bb_u.s.bb_leftsib;
+ }
+}
+
+STATIC void
+xfs_btree_set_sibling(
+ struct xfs_btree_cur *cur,
+ struct xfs_btree_block *block,
+ union xfs_btree_ptr *ptr,
+ int lr)
+{
+ ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
+
+ if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
+ if (lr == XFS_BB_RIGHTSIB)
+ block->bb_u.l.bb_rightsib = ptr->l;
+ else
+ block->bb_u.l.bb_leftsib = ptr->l;
+ } else {
+ if (lr == XFS_BB_RIGHTSIB)
+ block->bb_u.s.bb_rightsib = ptr->s;
+ else
+ block->bb_u.s.bb_leftsib = ptr->s;
+ }
+}
+
+STATIC void
+xfs_btree_init_block(
+ struct xfs_btree_cur *cur,
+ int level,
+ int numrecs,
+ struct xfs_btree_block *new) /* new block */
+{
+ new->bb_magic = cpu_to_be32(xfs_magics[cur->bc_btnum]);
+ new->bb_level = cpu_to_be16(level);
+ new->bb_numrecs = cpu_to_be16(numrecs);
+
+ if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
+ new->bb_u.l.bb_leftsib = cpu_to_be64(NULLDFSBNO);
+ new->bb_u.l.bb_rightsib = cpu_to_be64(NULLDFSBNO);
+ } else {
+ new->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
+ new->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
+ }
+}
+
+/*
+ * Return true if ptr is the last record in the btree and
+ * we need to track updateѕ to this record. The decision
+ * will be further refined in the update_lastrec method.
+ */
+STATIC int
+xfs_btree_is_lastrec(
+ struct xfs_btree_cur *cur,
+ struct xfs_btree_block *block,
+ int level)
+{
+ union xfs_btree_ptr ptr;
+
+ if (level > 0)
+ return 0;
+ if (!(cur->bc_flags & XFS_BTREE_LASTREC_UPDATE))
+ return 0;
+
+ xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
+ if (!xfs_btree_ptr_is_null(cur, &ptr))
+ return 0;
+ return 1;
+}
+
+STATIC void
+xfs_btree_buf_to_ptr(
+ struct xfs_btree_cur *cur,
+ struct xfs_buf *bp,
+ union xfs_btree_ptr *ptr)
+{
+ if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
+ ptr->l = cpu_to_be64(XFS_DADDR_TO_FSB(cur->bc_mp,
+ XFS_BUF_ADDR(bp)));
+ else {
+ ptr->s = cpu_to_be32(xfs_daddr_to_agbno(cur->bc_mp,
+ XFS_BUF_ADDR(bp)));
+ }
+}
+
+STATIC xfs_daddr_t
+xfs_btree_ptr_to_daddr(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_ptr *ptr)
+{
+ if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
+ ASSERT(be64_to_cpu(ptr->l) != NULLDFSBNO);
+
+ return XFS_FSB_TO_DADDR(cur->bc_mp, be64_to_cpu(ptr->l));
+ } else {
+ ASSERT(cur->bc_private.a.agno != NULLAGNUMBER);
+ ASSERT(be32_to_cpu(ptr->s) != NULLAGBLOCK);
+
+ return XFS_AGB_TO_DADDR(cur->bc_mp, cur->bc_private.a.agno,
+ be32_to_cpu(ptr->s));
+ }
+}
+
+STATIC void
+xfs_btree_set_refs(
+ struct xfs_btree_cur *cur,
+ struct xfs_buf *bp)
+{
+ switch (cur->bc_btnum) {
+ case XFS_BTNUM_BNO:
+ case XFS_BTNUM_CNT:
+ XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_MAP, XFS_ALLOC_BTREE_REF);
+ break;
+ case XFS_BTNUM_INO:
+ XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_INOMAP, XFS_INO_BTREE_REF);
+ break;
+ case XFS_BTNUM_BMAP:
+ XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_MAP, XFS_BMAP_BTREE_REF);
+ break;
+ default:
+ ASSERT(0);
+ }
+}
+
+STATIC int
+xfs_btree_get_buf_block(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_ptr *ptr,
+ int flags,
+ struct xfs_btree_block **block,
+ struct xfs_buf **bpp)
+{
+ struct xfs_mount *mp = cur->bc_mp;
+ xfs_daddr_t d;
+
+ /* need to sort out how callers deal with failures first */
+ ASSERT(!(flags & XBF_TRYLOCK));
+
+ d = xfs_btree_ptr_to_daddr(cur, ptr);
+ *bpp = xfs_trans_get_buf(cur->bc_tp, mp->m_ddev_targp, d,
+ mp->m_bsize, flags);
+
+ ASSERT(*bpp);
+ ASSERT(!XFS_BUF_GETERROR(*bpp));
+
+ *block = XFS_BUF_TO_BLOCK(*bpp);
+ return 0;
+}
+
+/*
+ * Read in the buffer at the given ptr and return the buffer and
+ * the block pointer within the buffer.
+ */
+STATIC int
+xfs_btree_read_buf_block(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_ptr *ptr,
+ int level,
+ int flags,
+ struct xfs_btree_block **block,
+ struct xfs_buf **bpp)
+{
+ struct xfs_mount *mp = cur->bc_mp;
+ xfs_daddr_t d;
+ int error;
+
+ /* need to sort out how callers deal with failures first */
+ ASSERT(!(flags & XBF_TRYLOCK));
+
+ d = xfs_btree_ptr_to_daddr(cur, ptr);
+ error = xfs_trans_read_buf(mp, cur->bc_tp, mp->m_ddev_targp, d,
+ mp->m_bsize, flags, bpp);
+ if (error)
+ return error;
+
+ ASSERT(*bpp != NULL);
+ ASSERT(!XFS_BUF_GETERROR(*bpp));
+
+ xfs_btree_set_refs(cur, *bpp);
+ *block = XFS_BUF_TO_BLOCK(*bpp);
+
+ error = xfs_btree_check_block(cur, *block, level, *bpp);
+ if (error)
+ xfs_trans_brelse(cur->bc_tp, *bpp);
+ return error;
+}
+
+/*
+ * Copy keys from one btree block to another.
+ */
+STATIC void
+xfs_btree_copy_keys(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_key *dst_key,
+ union xfs_btree_key *src_key,
+ int numkeys)
+{
+ ASSERT(numkeys >= 0);
+ memcpy(dst_key, src_key, numkeys * cur->bc_ops->key_len);
+}
+
+/*
+ * Copy records from one btree block to another.
+ */
+STATIC void
+xfs_btree_copy_recs(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_rec *dst_rec,
+ union xfs_btree_rec *src_rec,
+ int numrecs)
+{
+ ASSERT(numrecs >= 0);
+ memcpy(dst_rec, src_rec, numrecs * cur->bc_ops->rec_len);
+}
+
+/*
+ * Copy block pointers from one btree block to another.
+ */
+STATIC void
+xfs_btree_copy_ptrs(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_ptr *dst_ptr,
+ union xfs_btree_ptr *src_ptr,
+ int numptrs)
+{
+ ASSERT(numptrs >= 0);
+ memcpy(dst_ptr, src_ptr, numptrs * xfs_btree_ptr_len(cur));
+}
+
+/*
+ * Shift keys one index left/right inside a single btree block.
+ */
+STATIC void
+xfs_btree_shift_keys(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_key *key,
+ int dir,
+ int numkeys)
+{
+ char *dst_key;
+
+ ASSERT(numkeys >= 0);
+ ASSERT(dir == 1 || dir == -1);
+
+ dst_key = (char *)key + (dir * cur->bc_ops->key_len);
+ memmove(dst_key, key, numkeys * cur->bc_ops->key_len);
+}
+
+/*
+ * Shift records one index left/right inside a single btree block.
+ */
+STATIC void
+xfs_btree_shift_recs(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_rec *rec,
+ int dir,
+ int numrecs)
+{
+ char *dst_rec;
+
+ ASSERT(numrecs >= 0);
+ ASSERT(dir == 1 || dir == -1);
+
+ dst_rec = (char *)rec + (dir * cur->bc_ops->rec_len);
+ memmove(dst_rec, rec, numrecs * cur->bc_ops->rec_len);
+}
+
+/*
+ * Shift block pointers one index left/right inside a single btree block.
+ */
+STATIC void
+xfs_btree_shift_ptrs(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_ptr *ptr,
+ int dir,
+ int numptrs)
+{
+ char *dst_ptr;
+
+ ASSERT(numptrs >= 0);
+ ASSERT(dir == 1 || dir == -1);
+
+ dst_ptr = (char *)ptr + (dir * xfs_btree_ptr_len(cur));
+ memmove(dst_ptr, ptr, numptrs * xfs_btree_ptr_len(cur));
+}
+
+/*
+ * Log key values from the btree block.
+ */
+STATIC void
+xfs_btree_log_keys(
+ struct xfs_btree_cur *cur,
+ struct xfs_buf *bp,
+ int first,
+ int last)
+{
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+ XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
+
+ if (bp) {
+ xfs_trans_log_buf(cur->bc_tp, bp,
+ xfs_btree_key_offset(cur, first),
+ xfs_btree_key_offset(cur, last + 1) - 1);
+ } else {
+ xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
+ xfs_ilog_fbroot(cur->bc_private.b.whichfork));
+ }
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+}
+
+/*
+ * Log record values from the btree block.
+ */
+void
+xfs_btree_log_recs(
+ struct xfs_btree_cur *cur,
+ struct xfs_buf *bp,
+ int first,
+ int last)
+{
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+ XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
+
+ xfs_trans_log_buf(cur->bc_tp, bp,
+ xfs_btree_rec_offset(cur, first),
+ xfs_btree_rec_offset(cur, last + 1) - 1);
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+}
+
+/*
+ * Log block pointer fields from a btree block (nonleaf).
+ */
+STATIC void
+xfs_btree_log_ptrs(
+ struct xfs_btree_cur *cur, /* btree cursor */
+ struct xfs_buf *bp, /* buffer containing btree block */
+ int first, /* index of first pointer to log */
+ int last) /* index of last pointer to log */
+{
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+ XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
+
+ if (bp) {
+ struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
+ int level = xfs_btree_get_level(block);
+
+ xfs_trans_log_buf(cur->bc_tp, bp,
+ xfs_btree_ptr_offset(cur, first, level),
+ xfs_btree_ptr_offset(cur, last + 1, level) - 1);
+ } else {
+ xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
+ xfs_ilog_fbroot(cur->bc_private.b.whichfork));
+ }
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+}
+
+/*
+ * Log fields from a btree block header.
+ */
+void
+xfs_btree_log_block(
+ struct xfs_btree_cur *cur, /* btree cursor */
+ struct xfs_buf *bp, /* buffer containing btree block */
+ int fields) /* mask of fields: XFS_BB_... */
+{
+ int first; /* first byte offset logged */
+ int last; /* last byte offset logged */
+ static const short soffsets[] = { /* table of offsets (short) */
+ offsetof(struct xfs_btree_block, bb_magic),
+ offsetof(struct xfs_btree_block, bb_level),
+ offsetof(struct xfs_btree_block, bb_numrecs),
+ offsetof(struct xfs_btree_block, bb_u.s.bb_leftsib),
+ offsetof(struct xfs_btree_block, bb_u.s.bb_rightsib),
+ XFS_BTREE_SBLOCK_LEN
+ };
+ static const short loffsets[] = { /* table of offsets (long) */
+ offsetof(struct xfs_btree_block, bb_magic),
+ offsetof(struct xfs_btree_block, bb_level),
+ offsetof(struct xfs_btree_block, bb_numrecs),
+ offsetof(struct xfs_btree_block, bb_u.l.bb_leftsib),
+ offsetof(struct xfs_btree_block, bb_u.l.bb_rightsib),
+ XFS_BTREE_LBLOCK_LEN
+ };
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+ XFS_BTREE_TRACE_ARGBI(cur, bp, fields);
+
+ if (bp) {
+ xfs_btree_offsets(fields,
+ (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
+ loffsets : soffsets,
+ XFS_BB_NUM_BITS, &first, &last);
+ xfs_trans_log_buf(cur->bc_tp, bp, first, last);
+ } else {
+ xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
+ xfs_ilog_fbroot(cur->bc_private.b.whichfork));
+ }
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+}
+
+/*
+ * Increment cursor by one record at the level.
+ * For nonzero levels the leaf-ward information is untouched.
+ */
+int /* error */
+xfs_btree_increment(
+ struct xfs_btree_cur *cur,
+ int level,
+ int *stat) /* success/failure */
+{
+ struct xfs_btree_block *block;
+ union xfs_btree_ptr ptr;
+ struct xfs_buf *bp;
+ int error; /* error return value */
+ int lev;
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+ XFS_BTREE_TRACE_ARGI(cur, level);
+
+ ASSERT(level < cur->bc_nlevels);
+
+ /* Read-ahead to the right at this level. */
+ xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
+
+ /* Get a pointer to the btree block. */
+ block = xfs_btree_get_block(cur, level, &bp);
+
+#ifdef DEBUG
+ error = xfs_btree_check_block(cur, block, level, bp);
+ if (error)
+ goto error0;
+#endif
+
+ /* We're done if we remain in the block after the increment. */
+ if (++cur->bc_ptrs[level] <= xfs_btree_get_numrecs(block))
+ goto out1;
+
+ /* Fail if we just went off the right edge of the tree. */
+ xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
+ if (xfs_btree_ptr_is_null(cur, &ptr))
+ goto out0;
+
+ XFS_BTREE_STATS_INC(cur, increment);
+
+ /*
+ * March up the tree incrementing pointers.
+ * Stop when we don't go off the right edge of a block.
+ */
+ for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
+ block = xfs_btree_get_block(cur, lev, &bp);
+
+#ifdef DEBUG
+ error = xfs_btree_check_block(cur, block, lev, bp);
+ if (error)
+ goto error0;
+#endif
+
+ if (++cur->bc_ptrs[lev] <= xfs_btree_get_numrecs(block))
+ break;
+
+ /* Read-ahead the right block for the next loop. */
+ xfs_btree_readahead(cur, lev, XFS_BTCUR_RIGHTRA);
+ }
+
+ /*
+ * If we went off the root then we are either seriously
+ * confused or have the tree root in an inode.
+ */
+ if (lev == cur->bc_nlevels) {
+ if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
+ goto out0;
+ ASSERT(0);
+ error = EFSCORRUPTED;
+ goto error0;
+ }
+ ASSERT(lev < cur->bc_nlevels);
+
+ /*
+ * Now walk back down the tree, fixing up the cursor's buffer
+ * pointers and key numbers.
+ */
+ for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
+ union xfs_btree_ptr *ptrp;
+
+ ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
+ error = xfs_btree_read_buf_block(cur, ptrp, --lev,
+ 0, &block, &bp);
+ if (error)
+ goto error0;
+
+ xfs_btree_setbuf(cur, lev, bp);
+ cur->bc_ptrs[lev] = 1;
+ }
+out1:
+ 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;
+}
+
+/*
+ * Decrement cursor by one record at the level.
+ * For nonzero levels the leaf-ward information is untouched.
+ */
+int /* error */
+xfs_btree_decrement(
+ struct xfs_btree_cur *cur,
+ int level,
+ int *stat) /* success/failure */
+{
+ struct xfs_btree_block *block;
+ xfs_buf_t *bp;
+ int error; /* error return value */
+ int lev;
+ union xfs_btree_ptr ptr;
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+ XFS_BTREE_TRACE_ARGI(cur, level);
+
+ ASSERT(level < cur->bc_nlevels);
+
+ /* Read-ahead to the left at this level. */
+ xfs_btree_readahead(cur, level, XFS_BTCUR_LEFTRA);
+
+ /* We're done if we remain in the block after the decrement. */
+ if (--cur->bc_ptrs[level] > 0)
+ goto out1;
+
+ /* Get a pointer to the btree block. */
+ block = xfs_btree_get_block(cur, level, &bp);
+
+#ifdef DEBUG
+ error = xfs_btree_check_block(cur, block, level, bp);
+ if (error)
+ goto error0;
+#endif
+
+ /* Fail if we just went off the left edge of the tree. */
+ xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB);
+ if (xfs_btree_ptr_is_null(cur, &ptr))
+ goto out0;
+
+ XFS_BTREE_STATS_INC(cur, decrement);
+
+ /*
+ * March up the tree decrementing pointers.
+ * Stop when we don't go off the left edge of a block.
+ */
+ for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
+ if (--cur->bc_ptrs[lev] > 0)
+ break;
+ /* Read-ahead the left block for the next loop. */
+ xfs_btree_readahead(cur, lev, XFS_BTCUR_LEFTRA);
+ }
+
+ /*
+ * If we went off the root then we are seriously confused.
+ * or the root of the tree is in an inode.
+ */
+ if (lev == cur->bc_nlevels) {
+ if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
+ goto out0;
+ ASSERT(0);
+ error = EFSCORRUPTED;
+ goto error0;
+ }
+ ASSERT(lev < cur->bc_nlevels);
+
+ /*
+ * Now walk back down the tree, fixing up the cursor's buffer
+ * pointers and key numbers.
+ */
+ for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
+ union xfs_btree_ptr *ptrp;
+
+ ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
+ error = xfs_btree_read_buf_block(cur, ptrp, --lev,
+ 0, &block, &bp);
+ if (error)
+ goto error0;
+ xfs_btree_setbuf(cur, lev, bp);
+ cur->bc_ptrs[lev] = xfs_btree_get_numrecs(block);
+ }
+out1:
+ 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;
+}
+
+STATIC int
+xfs_btree_lookup_get_block(
+ struct xfs_btree_cur *cur, /* btree cursor */
+ int level, /* level in the btree */
+ union xfs_btree_ptr *pp, /* ptr to btree block */
+ struct xfs_btree_block **blkp) /* return btree block */
+{
+ struct xfs_buf *bp; /* buffer pointer for btree block */
+ int error = 0;
+
+ /* special case the root block if in an inode */
+ if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
+ (level == cur->bc_nlevels - 1)) {
+ *blkp = xfs_btree_get_iroot(cur);
+ return 0;
+ }
+
+ /*
+ * If the old buffer at this level for the disk address we are
+ * looking for re-use it.
+ *
+ * Otherwise throw it away and get a new one.
+ */
+ bp = cur->bc_bufs[level];
+ if (bp && XFS_BUF_ADDR(bp) == xfs_btree_ptr_to_daddr(cur, pp)) {
+ *blkp = XFS_BUF_TO_BLOCK(bp);
+ return 0;
+ }
+
+ error = xfs_btree_read_buf_block(cur, pp, level, 0, blkp, &bp);
+ if (error)
+ return error;
+
+ xfs_btree_setbuf(cur, level, bp);
+ return 0;
+}
+
+/*
+ * Get current search key. For level 0 we don't actually have a key
+ * structure so we make one up from the record. For all other levels
+ * we just return the right key.
+ */
+STATIC union xfs_btree_key *
+xfs_lookup_get_search_key(
+ struct xfs_btree_cur *cur,
+ int level,
+ int keyno,
+ struct xfs_btree_block *block,
+ union xfs_btree_key *kp)
+{
+ if (level == 0) {
+ cur->bc_ops->init_key_from_rec(kp,
+ xfs_btree_rec_addr(cur, keyno, block));
+ return kp;
+ }
+
+ return xfs_btree_key_addr(cur, keyno, block);
+}
+
+/*
+ * Lookup the record. The cursor is made to point to it, based on dir.
+ * Return 0 if can't find any such record, 1 for success.
+ */
+int /* error */
+xfs_btree_lookup(
+ struct xfs_btree_cur *cur, /* btree cursor */
+ xfs_lookup_t dir, /* <=, ==, or >= */
+ int *stat) /* success/failure */
+{
+ struct xfs_btree_block *block; /* current btree block */
+ __int64_t diff; /* difference for the current key */
+ int error; /* error return value */
+ int keyno; /* current key number */
+ int level; /* level in the btree */
+ union xfs_btree_ptr *pp; /* ptr to btree block */
+ union xfs_btree_ptr ptr; /* ptr to btree block */
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+ XFS_BTREE_TRACE_ARGI(cur, dir);
+
+ XFS_BTREE_STATS_INC(cur, lookup);
+
+ block = NULL;
+ keyno = 0;
+
+ /* initialise start pointer from cursor */
+ cur->bc_ops->init_ptr_from_cur(cur, &ptr);
+ pp = &ptr;
+
+ /*
+ * Iterate over each level in the btree, starting at the root.
+ * For each level above the leaves, find the key we need, based
+ * on the lookup record, then follow the corresponding block
+ * pointer down to the next level.
+ */
+ for (level = cur->bc_nlevels - 1, diff = 1; level >= 0; level--) {
+ /* Get the block we need to do the lookup on. */
+ error = xfs_btree_lookup_get_block(cur, level, pp, &block);
+ if (error)
+ goto error0;
+
+ if (diff == 0) {
+ /*
+ * If we already had a key match at a higher level, we
+ * know we need to use the first entry in this block.
+ */
+ keyno = 1;
+ } else {
+ /* Otherwise search this block. Do a binary search. */
+
+ int high; /* high entry number */
+ int low; /* low entry number */
+
+ /* Set low and high entry numbers, 1-based. */
+ low = 1;
+ high = xfs_btree_get_numrecs(block);
+ if (!high) {
+ /* Block is empty, must be an empty leaf. */
+ ASSERT(level == 0 && cur->bc_nlevels == 1);
+
+ cur->bc_ptrs[0] = dir != XFS_LOOKUP_LE;
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ *stat = 0;
+ return 0;
+ }
+
+ /* Binary search the block. */
+ while (low <= high) {
+ union xfs_btree_key key;
+ union xfs_btree_key *kp;
+
+ XFS_BTREE_STATS_INC(cur, compare);
+
+ /* keyno is average of low and high. */
+ keyno = (low + high) >> 1;
+
+ /* Get current search key */
+ kp = xfs_lookup_get_search_key(cur, level,
+ keyno, block, &key);
+
+ /*
+ * Compute difference to get next direction:
+ * - less than, move right
+ * - greater than, move left
+ * - equal, we're done
+ */
+ diff = cur->bc_ops->key_diff(cur, kp);
+ if (diff < 0)
+ low = keyno + 1;
+ else if (diff > 0)
+ high = keyno - 1;
+ else
+ break;
+ }
+ }
+
+ /*
+ * If there are more levels, set up for the next level
+ * by getting the block number and filling in the cursor.
+ */
+ if (level > 0) {
+ /*
+ * If we moved left, need the previous key number,
+ * unless there isn't one.
+ */
+ if (diff > 0 && --keyno < 1)
+ keyno = 1;
+ pp = xfs_btree_ptr_addr(cur, keyno, block);
+
+#ifdef DEBUG
+ error = xfs_btree_check_ptr(cur, pp, 0, level);
+ if (error)
+ goto error0;
+#endif
+ cur->bc_ptrs[level] = keyno;
+ }
+ }
+
+ /* Done with the search. See if we need to adjust the results. */
+ if (dir != XFS_LOOKUP_LE && diff < 0) {
+ keyno++;
+ /*
+ * If ge search and we went off the end of the block, but it's
+ * not the last block, we're in the wrong block.
+ */
+ xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
+ if (dir == XFS_LOOKUP_GE &&
+ keyno > xfs_btree_get_numrecs(block) &&
+ !xfs_btree_ptr_is_null(cur, &ptr)) {
+ int i;
+
+ cur->bc_ptrs[0] = keyno;
+ error = xfs_btree_increment(cur, 0, &i);
+ if (error)
+ goto error0;
+ XFS_WANT_CORRUPTED_RETURN(i == 1);
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ *stat = 1;
+ return 0;
+ }
+ } else if (dir == XFS_LOOKUP_LE && diff > 0)
+ keyno--;
+ cur->bc_ptrs[0] = keyno;
+
+ /* Return if we succeeded or not. */
+ if (keyno == 0 || keyno > xfs_btree_get_numrecs(block))
+ *stat = 0;
+ else if (dir != XFS_LOOKUP_EQ || diff == 0)
+ *stat = 1;
+ else
+ *stat = 0;
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ return 0;
+
+error0:
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
+ return error;
+}
+
+/*
+ * Update keys at all levels from here to the root along the cursor's path.
+ */
+STATIC int
+xfs_btree_updkey(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_key *keyp,
+ int level)
+{
+ struct xfs_btree_block *block;
+ struct xfs_buf *bp;
+ union xfs_btree_key *kp;
+ int ptr;
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+ XFS_BTREE_TRACE_ARGIK(cur, level, keyp);
+
+ ASSERT(!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) || level >= 1);
+
+ /*
+ * Go up the tree from this level toward the root.
+ * At each level, update the key value to the value input.
+ * Stop when we reach a level where the cursor isn't pointing
+ * at the first entry in the block.
+ */
+ for (ptr = 1; ptr == 1 && level < cur->bc_nlevels; level++) {
+#ifdef DEBUG
+ int error;
+#endif
+ block = xfs_btree_get_block(cur, level, &bp);
+#ifdef DEBUG
+ error = xfs_btree_check_block(cur, block, level, bp);
+ if (error) {
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
+ return error;
+ }
+#endif
+ ptr = cur->bc_ptrs[level];
+ kp = xfs_btree_key_addr(cur, ptr, block);
+ xfs_btree_copy_keys(cur, kp, keyp, 1);
+ xfs_btree_log_keys(cur, bp, ptr, ptr);
+ }
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ return 0;
+}
+
+/*
+ * Update the record referred to by cur to the value in the
+ * given record. This either works (return 0) or gets an
+ * EFSCORRUPTED error.
+ */
+int
+xfs_btree_update(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_rec *rec)
+{
+ struct xfs_btree_block *block;
+ struct xfs_buf *bp;
+ int error;
+ int ptr;
+ union xfs_btree_rec *rp;
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+ XFS_BTREE_TRACE_ARGR(cur, rec);
+
+ /* Pick up the current block. */
+ block = xfs_btree_get_block(cur, 0, &bp);
+
+#ifdef DEBUG
+ error = xfs_btree_check_block(cur, block, 0, bp);
+ if (error)
+ goto error0;
+#endif
+ /* Get the address of the rec to be updated. */
+ ptr = cur->bc_ptrs[0];
+ rp = xfs_btree_rec_addr(cur, ptr, block);
+
+ /* Fill in the new contents and log them. */
+ xfs_btree_copy_recs(cur, rp, rec, 1);
+ xfs_btree_log_recs(cur, bp, ptr, ptr);
+
+ /*
+ * If we are tracking the last record in the tree and
+ * we are at the far right edge of the tree, update it.
+ */
+ if (xfs_btree_is_lastrec(cur, block, 0)) {
+ cur->bc_ops->update_lastrec(cur, block, rec,
+ ptr, LASTREC_UPDATE);
+ }
+
+ /* Updating first rec in leaf. Pass new key value up to our parent. */
+ if (ptr == 1) {
+ union xfs_btree_key key;
+
+ cur->bc_ops->init_key_from_rec(&key, rec);
+ error = xfs_btree_updkey(cur, &key, 1);
+ if (error)
+ goto error0;
+ }
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ return 0;
+
+error0:
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
+ return error;
+}
+
+/*
+ * Move 1 record left from cur/level if possible.
+ * Update cur to reflect the new path.
+ */
+STATIC 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.
+ * Account 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);
+
+ ASSERT(cur->bc_ops->keys_inorder(cur,
+ 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);
+
+ ASSERT(cur->bc_ops->recs_inorder(cur,
+ 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.
+ */
+STATIC int /* error */
+xfs_btree_rshift(
+ 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 */
+ struct xfs_buf *rbp; /* right buffer pointer */
+ struct xfs_btree_block *right; /* right btree block */
+ struct xfs_btree_cur *tcur; /* temporary btree cursor */
+ union xfs_btree_ptr rptr; /* right block pointer */
+ union xfs_btree_key *rkp; /* right btree key */
+ int rrecs; /* right record count */
+ int lrecs; /* left record count */
+ int error; /* error return value */
+ int i; /* loop counter */
+
+ 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 "left". */
+ left = xfs_btree_get_block(cur, level, &lbp);
+
+#ifdef DEBUG
+ error = xfs_btree_check_block(cur, left, level, lbp);
+ if (error)
+ goto error0;
+#endif
+
+ /* If we've got no right sibling then we can't shift an entry right. */
+ xfs_btree_get_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
+ if (xfs_btree_ptr_is_null(cur, &rptr))
+ goto out0;
+
+ /*
+ * If the cursor entry is the one that would be moved, don't
+ * do it... it's too complicated.
+ */
+ lrecs = xfs_btree_get_numrecs(left);
+ if (cur->bc_ptrs[level] >= lrecs)
+ goto out0;
+
+ /* Set up the right neighbor as "right". */
+ error = xfs_btree_read_buf_block(cur, &rptr, level, 0, &right, &rbp);
+ if (error)
+ goto error0;
+
+ /* If it's full, it can't take another entry. */
+ rrecs = xfs_btree_get_numrecs(right);
+ if (rrecs == cur->bc_ops->get_maxrecs(cur, level))
+ goto out0;
+
+ XFS_BTREE_STATS_INC(cur, rshift);
+ XFS_BTREE_STATS_ADD(cur, moves, rrecs);
+
+ /*
+ * Make a hole at the start of the right neighbor block, then
+ * copy the last left block entry to the hole.
+ */
+ if (level > 0) {
+ /* It's a nonleaf. make a hole in the keys and ptrs */
+ union xfs_btree_key *lkp;
+ union xfs_btree_ptr *lpp;
+ union xfs_btree_ptr *rpp;
+
+ lkp = xfs_btree_key_addr(cur, lrecs, left);
+ lpp = xfs_btree_ptr_addr(cur, lrecs, left);
+ rkp = xfs_btree_key_addr(cur, 1, right);
+ rpp = xfs_btree_ptr_addr(cur, 1, right);
+
+#ifdef DEBUG
+ for (i = rrecs - 1; i >= 0; i--) {
+ error = xfs_btree_check_ptr(cur, rpp, i, level);
+ if (error)
+ goto error0;
+ }
+#endif
+
+ xfs_btree_shift_keys(cur, rkp, 1, rrecs);
+ xfs_btree_shift_ptrs(cur, rpp, 1, rrecs);
+
+#ifdef DEBUG
+ error = xfs_btree_check_ptr(cur, lpp, 0, level);
+ if (error)
+ goto error0;
+#endif
+
+ /* Now put the new data in, and log it. */
+ xfs_btree_copy_keys(cur, rkp, lkp, 1);
+ xfs_btree_copy_ptrs(cur, rpp, lpp, 1);
+
+ xfs_btree_log_keys(cur, rbp, 1, rrecs + 1);
+ xfs_btree_log_ptrs(cur, rbp, 1, rrecs + 1);
+
+ ASSERT(cur->bc_ops->keys_inorder(cur, rkp,
+ xfs_btree_key_addr(cur, 2, right)));
+ } else {
+ /* It's a leaf. make a hole in the records */
+ union xfs_btree_rec *lrp;
+ union xfs_btree_rec *rrp;
+
+ lrp = xfs_btree_rec_addr(cur, lrecs, left);
+ rrp = xfs_btree_rec_addr(cur, 1, right);
+
+ xfs_btree_shift_recs(cur, rrp, 1, rrecs);
+
+ /* Now put the new data in, and log it. */
+ xfs_btree_copy_recs(cur, rrp, lrp, 1);
+ xfs_btree_log_recs(cur, rbp, 1, rrecs + 1);
+
+ cur->bc_ops->init_key_from_rec(&key, rrp);
+ rkp = &key;
+
+ ASSERT(cur->bc_ops->recs_inorder(cur, rrp,
+ xfs_btree_rec_addr(cur, 2, right)));
+ }
+
+ /*
+ * Decrement and log left's numrecs, bump and log right's numrecs.
+ */
+ 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);
+
+ /*
+ * Using a temporary cursor, update the parent key values of the
+ * block on the right.
+ */
+ error = xfs_btree_dup_cursor(cur, &tcur);
+ if (error)
+ goto error0;
+ i = xfs_btree_lastrec(tcur, level);
+ XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
+
+ error = xfs_btree_increment(tcur, level, &i);
+ if (error)
+ goto error1;
+
+ error = xfs_btree_updkey(tcur, rkp, level + 1);
+ if (error)
+ goto error1;
+
+ xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
+
+ 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;
+
+error1:
+ XFS_BTREE_TRACE_CURSOR(tcur, XBT_ERROR);
+ xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
+ return error;
+}
+
+/*
+ * Split cur/level block in half.
+ * Return new block number and the key to its first
+ * record (to be inserted into parent).
+ */
+STATIC int /* error */
+xfs_btree_split(
+ struct xfs_btree_cur *cur,
+ int level,
+ union xfs_btree_ptr *ptrp,
+ union xfs_btree_key *key,
+ struct xfs_btree_cur **curp,
+ int *stat) /* success/failure */
+{
+ union xfs_btree_ptr lptr; /* left sibling block ptr */
+ struct xfs_buf *lbp; /* left buffer pointer */
+ struct xfs_btree_block *left; /* left btree block */
+ union xfs_btree_ptr rptr; /* right sibling block ptr */
+ struct xfs_buf *rbp; /* right buffer pointer */
+ struct xfs_btree_block *right; /* right btree block */
+ union xfs_btree_ptr rrptr; /* right-right sibling ptr */
+ struct xfs_buf *rrbp; /* right-right buffer pointer */
+ struct xfs_btree_block *rrblock; /* right-right btree block */
+ int lrecs;
+ int rrecs;
+ int src_index;
+ int error; /* error return value */
+#ifdef DEBUG
+ int i;
+#endif
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+ XFS_BTREE_TRACE_ARGIPK(cur, level, *ptrp, key);
+
+ XFS_BTREE_STATS_INC(cur, split);
+
+ /* Set up left block (current one). */
+ left = xfs_btree_get_block(cur, level, &lbp);
+
+#ifdef DEBUG
+ error = xfs_btree_check_block(cur, left, level, lbp);
+ if (error)
+ goto error0;
+#endif
+
+ xfs_btree_buf_to_ptr(cur, lbp, &lptr);
+
+ /* Allocate the new block. If we can't do it, we're toast. Give up. */
+ error = cur->bc_ops->alloc_block(cur, &lptr, &rptr, 1, stat);
+ if (error)
+ goto error0;
+ if (*stat == 0)
+ goto out0;
+ XFS_BTREE_STATS_INC(cur, alloc);
+
+ /* Set up the new block as "right". */
+ error = xfs_btree_get_buf_block(cur, &rptr, 0, &right, &rbp);
+ if (error)
+ goto error0;
+
+ /* Fill in the btree header for the new right block. */
+ xfs_btree_init_block(cur, xfs_btree_get_level(left), 0, right);
+
+ /*
+ * Split the entries between the old and the new block evenly.
+ * Make sure that if there's an odd number of entries now, that
+ * each new block will have the same number of entries.
+ */
+ lrecs = xfs_btree_get_numrecs(left);
+ rrecs = lrecs / 2;
+ if ((lrecs & 1) && cur->bc_ptrs[level] <= rrecs + 1)
+ rrecs++;
+ src_index = (lrecs - rrecs + 1);
+
+ XFS_BTREE_STATS_ADD(cur, moves, rrecs);
+
+ /*
+ * Copy btree block entries from the left block over to the
+ * new block, the right. Update the right block and log the
+ * changes.
+ */
+ 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 */
+ union xfs_btree_key *rkp; /* right btree key */
+ union xfs_btree_ptr *rpp; /* right address pointer */
+
+ lkp = xfs_btree_key_addr(cur, src_index, left);
+ lpp = xfs_btree_ptr_addr(cur, src_index, left);
+ rkp = xfs_btree_key_addr(cur, 1, right);
+ rpp = xfs_btree_ptr_addr(cur, 1, right);
+
+#ifdef DEBUG
+ for (i = src_index; i < rrecs; i++) {
+ error = xfs_btree_check_ptr(cur, lpp, i, level);
+ if (error)
+ goto error0;
+ }
+#endif
+
+ xfs_btree_copy_keys(cur, rkp, lkp, rrecs);
+ xfs_btree_copy_ptrs(cur, rpp, lpp, rrecs);
+
+ xfs_btree_log_keys(cur, rbp, 1, rrecs);
+ xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
+
+ /* Grab the keys to the entries moved to the right block */
+ xfs_btree_copy_keys(cur, key, rkp, 1);
+ } else {
+ /* It's a leaf. Move records. */
+ union xfs_btree_rec *lrp; /* left record pointer */
+ union xfs_btree_rec *rrp; /* right record pointer */
+
+ lrp = xfs_btree_rec_addr(cur, src_index, left);
+ rrp = xfs_btree_rec_addr(cur, 1, right);
+
+ xfs_btree_copy_recs(cur, rrp, lrp, rrecs);
+ xfs_btree_log_recs(cur, rbp, 1, rrecs);
+
+ cur->bc_ops->init_key_from_rec(key,
+ xfs_btree_rec_addr(cur, 1, right));
+ }
+
+
+ /*
+ * Find the left block number by looking in the buffer.
+ * Adjust numrecs, sibling pointers.
+ */
+ xfs_btree_get_sibling(cur, left, &rrptr, XFS_BB_RIGHTSIB);
+ xfs_btree_set_sibling(cur, right, &rrptr, XFS_BB_RIGHTSIB);
+ xfs_btree_set_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
+ xfs_btree_set_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
+
+ lrecs -= rrecs;
+ xfs_btree_set_numrecs(left, lrecs);
+ xfs_btree_set_numrecs(right, xfs_btree_get_numrecs(right) + rrecs);
+
+ xfs_btree_log_block(cur, rbp, XFS_BB_ALL_BITS);
+ xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
+
+ /*
+ * If there's a block to the new block's right, make that block
+ * point back to right instead of to left.
+ */
+ if (!xfs_btree_ptr_is_null(cur, &rrptr)) {
+ error = xfs_btree_read_buf_block(cur, &rrptr, level,
+ 0, &rrblock, &rrbp);
+ if (error)
+ goto error0;
+ xfs_btree_set_sibling(cur, rrblock, &rptr, XFS_BB_LEFTSIB);
+ xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB);
+ }
+ /*
+ * If the cursor is really in the right block, move it there.
+ * If it's just pointing past the last entry in left, then we'll
+ * insert there, so don't change anything in that case.
+ */
+ if (cur->bc_ptrs[level] > lrecs + 1) {
+ xfs_btree_setbuf(cur, level, rbp);
+ cur->bc_ptrs[level] -= lrecs;
+ }
+ /*
+ * If there are more levels, we'll need another cursor which refers
+ * the right block, no matter where this cursor was.
+ */
+ if (level + 1 < cur->bc_nlevels) {
+ error = xfs_btree_dup_cursor(cur, curp);
+ if (error)
+ goto error0;
+ (*curp)->bc_ptrs[level + 1]++;
+ }
+ *ptrp = rptr;
+ 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;
+}
+
+/*
+ * Copy the old inode root contents into a real block and make the
+ * broot point to it.
+ */
+int /* error */
+xfs_btree_new_iroot(
+ struct xfs_btree_cur *cur, /* btree cursor */
+ int *logflags, /* logging flags for inode */
+ int *stat) /* return status - 0 fail */
+{
+ struct xfs_buf *cbp; /* buffer for cblock */
+ struct xfs_btree_block *block; /* btree block */
+ struct xfs_btree_block *cblock; /* child btree block */
+ union xfs_btree_key *ckp; /* child key pointer */
+ union xfs_btree_ptr *cpp; /* child ptr pointer */
+ union xfs_btree_key *kp; /* pointer to btree key */
+ union xfs_btree_ptr *pp; /* pointer to block addr */
+ union xfs_btree_ptr nptr; /* new block addr */
+ int level; /* btree level */
+ int error; /* error return code */
+#ifdef DEBUG
+ int i; /* loop counter */
+#endif
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+ XFS_BTREE_STATS_INC(cur, newroot);
+
+ ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
+
+ level = cur->bc_nlevels - 1;
+
+ block = xfs_btree_get_iroot(cur);
+ pp = xfs_btree_ptr_addr(cur, 1, block);
+
+ /* Allocate the new block. If we can't do it, we're toast. Give up. */
+ error = cur->bc_ops->alloc_block(cur, pp, &nptr, 1, stat);
+ if (error)
+ goto error0;
+ if (*stat == 0) {
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ return 0;
+ }
+ XFS_BTREE_STATS_INC(cur, alloc);
+
+ /* Copy the root into a real block. */
+ error = xfs_btree_get_buf_block(cur, &nptr, 0, &cblock, &cbp);
+ if (error)
+ goto error0;
+
+ memcpy(cblock, block, xfs_btree_block_len(cur));
+
+ be16_add_cpu(&block->bb_level, 1);
+ xfs_btree_set_numrecs(block, 1);
+ cur->bc_nlevels++;
+ cur->bc_ptrs[level + 1] = 1;
+
+ kp = xfs_btree_key_addr(cur, 1, block);
+ ckp = xfs_btree_key_addr(cur, 1, cblock);
+ xfs_btree_copy_keys(cur, ckp, kp, xfs_btree_get_numrecs(cblock));
+
+ cpp = xfs_btree_ptr_addr(cur, 1, cblock);
+#ifdef DEBUG
+ for (i = 0; i < be16_to_cpu(cblock->bb_numrecs); i++) {
+ error = xfs_btree_check_ptr(cur, pp, i, level);
+ if (error)
+ goto error0;
+ }
+#endif
+ xfs_btree_copy_ptrs(cur, cpp, pp, xfs_btree_get_numrecs(cblock));
+
+#ifdef DEBUG
+ error = xfs_btree_check_ptr(cur, &nptr, 0, level);
+ if (error)
+ goto error0;
+#endif
+ xfs_btree_copy_ptrs(cur, pp, &nptr, 1);
+
+ xfs_iroot_realloc(cur->bc_private.b.ip,
+ 1 - xfs_btree_get_numrecs(cblock),
+ cur->bc_private.b.whichfork);
+
+ xfs_btree_setbuf(cur, level, cbp);
+
+ /*
+ * Do all this logging at the end so that
+ * the root is at the right level.
+ */
+ xfs_btree_log_block(cur, cbp, XFS_BB_ALL_BITS);
+ xfs_btree_log_keys(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs));
+ xfs_btree_log_ptrs(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs));
+
+ *logflags |=
+ XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork);
+ *stat = 1;
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ return 0;
+error0:
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
+ return error;
+}
+
+/*
+ * Allocate a new root block, fill it in.
+ */
+STATIC int /* error */
+xfs_btree_new_root(
+ struct xfs_btree_cur *cur, /* btree cursor */
+ int *stat) /* success/failure */
+{
+ struct xfs_btree_block *block; /* one half of the old root block */
+ struct xfs_buf *bp; /* buffer containing block */
+ int error; /* error return value */
+ struct xfs_buf *lbp; /* left buffer pointer */
+ struct xfs_btree_block *left; /* left btree block */
+ struct xfs_buf *nbp; /* new (root) buffer */
+ struct xfs_btree_block *new; /* new (root) btree block */
+ int nptr; /* new value for key index, 1 or 2 */
+ struct xfs_buf *rbp; /* right buffer pointer */
+ struct xfs_btree_block *right; /* right btree block */
+ union xfs_btree_ptr rptr;
+ union xfs_btree_ptr lptr;
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+ XFS_BTREE_STATS_INC(cur, newroot);
+
+ /* initialise our start point from the cursor */
+ cur->bc_ops->init_ptr_from_cur(cur, &rptr);
+
+ /* Allocate the new block. If we can't do it, we're toast. Give up. */
+ error = cur->bc_ops->alloc_block(cur, &rptr, &lptr, 1, stat);
+ if (error)
+ goto error0;
+ if (*stat == 0)
+ goto out0;
+ XFS_BTREE_STATS_INC(cur, alloc);
+
+ /* Set up the new block. */
+ error = xfs_btree_get_buf_block(cur, &lptr, 0, &new, &nbp);
+ if (error)
+ goto error0;
+
+ /* Set the root in the holding structure increasing the level by 1. */
+ cur->bc_ops->set_root(cur, &lptr, 1);
+
+ /*
+ * At the previous root level there are now two blocks: the old root,
+ * and the new block generated when it was split. We don't know which
+ * one the cursor is pointing at, so we set up variables "left" and
+ * "right" for each case.
+ */
+ block = xfs_btree_get_block(cur, cur->bc_nlevels - 1, &bp);
+
+#ifdef DEBUG
+ error = xfs_btree_check_block(cur, block, cur->bc_nlevels - 1, bp);
+ if (error)
+ goto error0;
+#endif
+
+ xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
+ if (!xfs_btree_ptr_is_null(cur, &rptr)) {
+ /* Our block is left, pick up the right block. */
+ lbp = bp;
+ xfs_btree_buf_to_ptr(cur, lbp, &lptr);
+ left = block;
+ error = xfs_btree_read_buf_block(cur, &rptr,
+ cur->bc_nlevels - 1, 0, &right, &rbp);
+ if (error)
+ goto error0;
+ bp = rbp;
+ nptr = 1;
+ } else {
+ /* Our block is right, pick up the left block. */
+ rbp = bp;
+ xfs_btree_buf_to_ptr(cur, rbp, &rptr);
+ right = block;
+ xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
+ error = xfs_btree_read_buf_block(cur, &lptr,
+ cur->bc_nlevels - 1, 0, &left, &lbp);
+ if (error)
+ goto error0;
+ bp = lbp;
+ nptr = 2;
+ }
+ /* Fill in the new block's btree header and log it. */
+ xfs_btree_init_block(cur, cur->bc_nlevels, 2, new);
+ xfs_btree_log_block(cur, nbp, XFS_BB_ALL_BITS);
+ ASSERT(!xfs_btree_ptr_is_null(cur, &lptr) &&
+ !xfs_btree_ptr_is_null(cur, &rptr));
+
+ /* Fill in the key data in the new root. */
+ if (xfs_btree_get_level(left) > 0) {
+ xfs_btree_copy_keys(cur,
+ xfs_btree_key_addr(cur, 1, new),
+ xfs_btree_key_addr(cur, 1, left), 1);
+ xfs_btree_copy_keys(cur,
+ xfs_btree_key_addr(cur, 2, new),
+ xfs_btree_key_addr(cur, 1, right), 1);
+ } else {
+ cur->bc_ops->init_key_from_rec(
+ xfs_btree_key_addr(cur, 1, new),
+ xfs_btree_rec_addr(cur, 1, left));
+ cur->bc_ops->init_key_from_rec(
+ xfs_btree_key_addr(cur, 2, new),
+ xfs_btree_rec_addr(cur, 1, right));
+ }
+ xfs_btree_log_keys(cur, nbp, 1, 2);
+
+ /* Fill in the pointer data in the new root. */
+ xfs_btree_copy_ptrs(cur,
+ xfs_btree_ptr_addr(cur, 1, new), &lptr, 1);
+ xfs_btree_copy_ptrs(cur,
+ xfs_btree_ptr_addr(cur, 2, new), &rptr, 1);
+ xfs_btree_log_ptrs(cur, nbp, 1, 2);
+
+ /* Fix up the cursor. */
+ xfs_btree_setbuf(cur, cur->bc_nlevels, nbp);
+ cur->bc_ptrs[cur->bc_nlevels] = nptr;
+ cur->bc_nlevels++;
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ *stat = 1;
+ return 0;
+error0:
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
+ return error;
+out0:
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ *stat = 0;
+ return 0;
+}
+
+STATIC int
+xfs_btree_make_block_unfull(
+ struct xfs_btree_cur *cur, /* btree cursor */
+ int level, /* btree level */
+ int numrecs,/* # of recs in block */
+ int *oindex,/* old tree index */
+ int *index, /* new tree index */
+ union xfs_btree_ptr *nptr, /* new btree ptr */
+ struct xfs_btree_cur **ncur, /* new btree cursor */
+ union xfs_btree_rec *nrec, /* new record */
+ int *stat)
+{
+ union xfs_btree_key key; /* new btree key value */
+ int error = 0;
+
+ if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
+ level == cur->bc_nlevels - 1) {
+ struct xfs_inode *ip = cur->bc_private.b.ip;
+
+ if (numrecs < cur->bc_ops->get_dmaxrecs(cur, level)) {
+ /* A root block that can be made bigger. */
+
+ xfs_iroot_realloc(ip, 1, cur->bc_private.b.whichfork);
+ } else {
+ /* A root block that needs replacing */
+ int logflags = 0;
+
+ error = xfs_btree_new_iroot(cur, &logflags, stat);
+ if (error || *stat == 0)
+ return error;
+
+ xfs_trans_log_inode(cur->bc_tp, ip, logflags);
+ }
+
+ return 0;
+ }
+
+ /* First, try shifting an entry to the right neighbor. */
+ error = xfs_btree_rshift(cur, level, stat);
+ if (error || *stat)
+ return error;
+
+ /* Next, try shifting an entry to the left neighbor. */
+ error = xfs_btree_lshift(cur, level, stat);
+ if (error)
+ return error;
+
+ if (*stat) {
+ *oindex = *index = cur->bc_ptrs[level];
+ return 0;
+ }
+
+ /*
+ * Next, try splitting the current block in half.
+ *
+ * If this works we have to re-set our variables because we
+ * could be in a different block now.
+ */
+ error = xfs_btree_split(cur, level, nptr, &key, ncur, stat);
+ if (error || *stat == 0)
+ return error;
+
+
+ *index = cur->bc_ptrs[level];
+ cur->bc_ops->init_rec_from_key(&key, nrec);
+ return 0;
+}
+
+/*
+ * Insert one record/level. Return information to the caller
+ * allowing the next level up to proceed if necessary.
+ */
+STATIC int
+xfs_btree_insrec(
+ struct xfs_btree_cur *cur, /* btree cursor */
+ int level, /* level to insert record at */
+ union xfs_btree_ptr *ptrp, /* i/o: block number inserted */
+ union xfs_btree_rec *recp, /* i/o: record data inserted */
+ struct xfs_btree_cur **curp, /* output: new cursor replacing cur */
+ int *stat) /* success/failure */
+{
+ struct xfs_btree_block *block; /* btree block */
+ struct xfs_buf *bp; /* buffer for block */
+ union xfs_btree_key key; /* btree key */
+ union xfs_btree_ptr nptr; /* new block ptr */
+ struct xfs_btree_cur *ncur; /* new btree cursor */
+ union xfs_btree_rec nrec; /* new record count */
+ int optr; /* old key/record index */
+ int ptr; /* key/record index */
+ int numrecs;/* number of records */
+ int error; /* error return value */
+#ifdef DEBUG
+ int i;
+#endif
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+ XFS_BTREE_TRACE_ARGIPR(cur, level, *ptrp, recp);
+
+ ncur = NULL;
+
+ /*
+ * If we have an external root pointer, and we've made it to the
+ * root level, allocate a new root block and we're done.
+ */
+ if (!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
+ (level >= cur->bc_nlevels)) {
+ error = xfs_btree_new_root(cur, stat);
+ xfs_btree_set_ptr_null(cur, ptrp);
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ return error;
+ }
+
+ /* If we're off the left edge, return failure. */
+ ptr = cur->bc_ptrs[level];
+ if (ptr == 0) {
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ *stat = 0;
+ return 0;
+ }
+
+ /* Make a key out of the record data to be inserted, and save it. */
+ cur->bc_ops->init_key_from_rec(&key, recp);
+
+ optr = ptr;
+
+ XFS_BTREE_STATS_INC(cur, insrec);
+
+ /* Get pointers to the btree buffer and block. */
+ block = xfs_btree_get_block(cur, level, &bp);
+ numrecs = xfs_btree_get_numrecs(block);
+
+#ifdef DEBUG
+ error = xfs_btree_check_block(cur, block, level, bp);
+ if (error)
+ goto error0;
+
+ /* Check that the new entry is being inserted in the right place. */
+ if (ptr <= numrecs) {
+ if (level == 0) {
+ ASSERT(cur->bc_ops->recs_inorder(cur, recp,
+ xfs_btree_rec_addr(cur, ptr, block)));
+ } else {
+ ASSERT(cur->bc_ops->keys_inorder(cur, &key,
+ xfs_btree_key_addr(cur, ptr, block)));
+ }
+ }
+#endif
+
+ /*
+ * If the block is full, we can't insert the new entry until we
+ * make the block un-full.
+ */
+ xfs_btree_set_ptr_null(cur, &nptr);
+ if (numrecs == cur->bc_ops->get_maxrecs(cur, level)) {
+ error = xfs_btree_make_block_unfull(cur, level, numrecs,
+ &optr, &ptr, &nptr, &ncur, &nrec, stat);
+ if (error || *stat == 0)
+ goto error0;
+ }
+
+ /*
+ * The current block may have changed if the block was
+ * previously full and we have just made space in it.
+ */
+ block = xfs_btree_get_block(cur, level, &bp);
+ numrecs = xfs_btree_get_numrecs(block);
+
+#ifdef DEBUG
+ error = xfs_btree_check_block(cur, block, level, bp);
+ if (error)
+ return error;
+#endif
+
+ /*
+ * At this point we know there's room for our new entry in the block
+ * we're pointing at.
+ */
+ XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr + 1);
+
+ if (level > 0) {
+ /* It's a nonleaf. make a hole in the keys and ptrs */
+ union xfs_btree_key *kp;
+ union xfs_btree_ptr *pp;
+
+ kp = xfs_btree_key_addr(cur, ptr, block);
+ pp = xfs_btree_ptr_addr(cur, ptr, block);
+
+#ifdef DEBUG
+ for (i = numrecs - ptr; i >= 0; i--) {
+ error = xfs_btree_check_ptr(cur, pp, i, level);
+ if (error)
+ return error;
+ }
+#endif
+
+ xfs_btree_shift_keys(cur, kp, 1, numrecs - ptr + 1);
+ xfs_btree_shift_ptrs(cur, pp, 1, numrecs - ptr + 1);
+
+#ifdef DEBUG
+ error = xfs_btree_check_ptr(cur, ptrp, 0, level);
+ if (error)
+ goto error0;
+#endif
+
+ /* Now put the new data in, bump numrecs and log it. */
+ xfs_btree_copy_keys(cur, kp, &key, 1);
+ xfs_btree_copy_ptrs(cur, pp, ptrp, 1);
+ numrecs++;
+ xfs_btree_set_numrecs(block, numrecs);
+ xfs_btree_log_ptrs(cur, bp, ptr, numrecs);
+ xfs_btree_log_keys(cur, bp, ptr, numrecs);
+#ifdef DEBUG
+ if (ptr < numrecs) {
+ ASSERT(cur->bc_ops->keys_inorder(cur, kp,
+ xfs_btree_key_addr(cur, ptr + 1, block)));
+ }
+#endif
+ } else {
+ /* It's a leaf. make a hole in the records */
+ union xfs_btree_rec *rp;
+
+ rp = xfs_btree_rec_addr(cur, ptr, block);
+
+ xfs_btree_shift_recs(cur, rp, 1, numrecs - ptr + 1);
+
+ /* Now put the new data in, bump numrecs and log it. */
+ xfs_btree_copy_recs(cur, rp, recp, 1);
+ xfs_btree_set_numrecs(block, ++numrecs);
+ xfs_btree_log_recs(cur, bp, ptr, numrecs);
+#ifdef DEBUG
+ if (ptr < numrecs) {
+ ASSERT(cur->bc_ops->recs_inorder(cur, rp,
+ xfs_btree_rec_addr(cur, ptr + 1, block)));
+ }
+#endif
+ }
+
+ /* Log the new number of records in the btree header. */
+ xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS);
+
+ /* If we inserted at the start of a block, update the parents' keys. */
+ if (optr == 1) {
+ error = xfs_btree_updkey(cur, &key, level + 1);
+ if (error)
+ goto error0;
+ }
+
+ /*
+ * If we are tracking the last record in the tree and
+ * we are at the far right edge of the tree, update it.
+ */
+ if (xfs_btree_is_lastrec(cur, block, level)) {
+ cur->bc_ops->update_lastrec(cur, block, recp,
+ ptr, LASTREC_INSREC);
+ }
+
+ /*
+ * Return the new block number, if any.
+ * If there is one, give back a record value and a cursor too.
+ */
+ *ptrp = nptr;
+ if (!xfs_btree_ptr_is_null(cur, &nptr)) {
+ *recp = nrec;
+ *curp = ncur;
+ }
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ *stat = 1;
+ return 0;
+
+error0:
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
+ return error;
+}
+
+/*
+ * Insert the record at the point referenced by cur.
+ *
+ * A multi-level split of the tree on insert will invalidate the original
+ * cursor. All callers of this function should assume that the cursor is
+ * no longer valid and revalidate it.
+ */
+int
+xfs_btree_insert(
+ struct xfs_btree_cur *cur,
+ int *stat)
+{
+ int error; /* error return value */
+ int i; /* result value, 0 for failure */
+ int level; /* current level number in btree */
+ union xfs_btree_ptr nptr; /* new block number (split result) */
+ struct xfs_btree_cur *ncur; /* new cursor (split result) */
+ struct xfs_btree_cur *pcur; /* previous level's cursor */
+ union xfs_btree_rec rec; /* record to insert */
+
+ level = 0;
+ ncur = NULL;
+ pcur = cur;
+
+ xfs_btree_set_ptr_null(cur, &nptr);
+ cur->bc_ops->init_rec_from_cur(cur, &rec);
+
+ /*
+ * Loop going up the tree, starting at the leaf level.
+ * Stop when we don't get a split block, that must mean that
+ * the insert is finished with this level.
+ */
+ do {
+ /*
+ * Insert nrec/nptr into this level of the tree.
+ * Note if we fail, nptr will be null.
+ */
+ error = xfs_btree_insrec(pcur, level, &nptr, &rec, &ncur, &i);
+ if (error) {
+ if (pcur != cur)
+ xfs_btree_del_cursor(pcur, XFS_BTREE_ERROR);
+ goto error0;
+ }
+
+ XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
+ level++;
+
+ /*
+ * See if the cursor we just used is trash.
+ * Can't trash the caller's cursor, but otherwise we should
+ * if ncur is a new cursor or we're about to be done.
+ */
+ if (pcur != cur &&
+ (ncur || xfs_btree_ptr_is_null(cur, &nptr))) {
+ /* Save the state from the cursor before we trash it */
+ if (cur->bc_ops->update_cursor)
+ cur->bc_ops->update_cursor(pcur, cur);
+ cur->bc_nlevels = pcur->bc_nlevels;
+ xfs_btree_del_cursor(pcur, XFS_BTREE_NOERROR);
+ }
+ /* If we got a new cursor, switch to it. */
+ if (ncur) {
+ pcur = ncur;
+ ncur = NULL;
+ }
+ } while (!xfs_btree_ptr_is_null(cur, &nptr));
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ *stat = i;
+ return 0;
+error0:
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
+ return error;
+}
+
+/*
+ * Try to merge a non-leaf block back into the inode root.
+ *
+ * Note: the killroot names comes from the fact that we're effectively
+ * killing the old root block. But because we can't just delete the
+ * inode we have to copy the single block it was pointing to into the
+ * inode.
+ */
+STATIC int
+xfs_btree_kill_iroot(
+ struct xfs_btree_cur *cur)
+{
+ int whichfork = cur->bc_private.b.whichfork;
+ struct xfs_inode *ip = cur->bc_private.b.ip;
+ struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
+ struct xfs_btree_block *block;
+ struct xfs_btree_block *cblock;
+ union xfs_btree_key *kp;
+ union xfs_btree_key *ckp;
+ union xfs_btree_ptr *pp;
+ union xfs_btree_ptr *cpp;
+ struct xfs_buf *cbp;
+ int level;
+ int index;
+ int numrecs;
+#ifdef DEBUG
+ union xfs_btree_ptr ptr;
+ int i;
+#endif
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+
+ ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
+ ASSERT(cur->bc_nlevels > 1);
+
+ /*
+ * Don't deal with the root block needs to be a leaf case.
+ * We're just going to turn the thing back into extents anyway.
+ */
+ level = cur->bc_nlevels - 1;
+ if (level == 1)
+ goto out0;
+
+ /*
+ * Give up if the root has multiple children.
+ */
+ block = xfs_btree_get_iroot(cur);
+ if (xfs_btree_get_numrecs(block) != 1)
+ goto out0;
+
+ cblock = xfs_btree_get_block(cur, level - 1, &cbp);
+ numrecs = xfs_btree_get_numrecs(cblock);
+
+ /*
+ * Only do this if the next level will fit.
+ * Then the data must be copied up to the inode,
+ * instead of freeing the root you free the next level.
+ */
+ if (numrecs > cur->bc_ops->get_dmaxrecs(cur, level))
+ goto out0;
+
+ XFS_BTREE_STATS_INC(cur, killroot);
+
+#ifdef DEBUG
+ xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB);
+ ASSERT(xfs_btree_ptr_is_null(cur, &ptr));
+ xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
+ ASSERT(xfs_btree_ptr_is_null(cur, &ptr));
+#endif
+
+ index = numrecs - cur->bc_ops->get_maxrecs(cur, level);
+ if (index) {
+ xfs_iroot_realloc(cur->bc_private.b.ip, index,
+ cur->bc_private.b.whichfork);
+ block = ifp->if_broot;
+ }
+
+ be16_add_cpu(&block->bb_numrecs, index);
+ ASSERT(block->bb_numrecs == cblock->bb_numrecs);
+
+ kp = xfs_btree_key_addr(cur, 1, block);
+ ckp = xfs_btree_key_addr(cur, 1, cblock);
+ xfs_btree_copy_keys(cur, kp, ckp, numrecs);
+
+ pp = xfs_btree_ptr_addr(cur, 1, block);
+ cpp = xfs_btree_ptr_addr(cur, 1, cblock);
+#ifdef DEBUG
+ for (i = 0; i < numrecs; i++) {
+ int error;
+
+ error = xfs_btree_check_ptr(cur, cpp, i, level - 1);
+ if (error) {
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
+ return error;
+ }
+ }
+#endif
+ xfs_btree_copy_ptrs(cur, pp, cpp, numrecs);
+
+ cur->bc_ops->free_block(cur, cbp);
+ XFS_BTREE_STATS_INC(cur, free);
+
+ cur->bc_bufs[level - 1] = NULL;
+ be16_add_cpu(&block->bb_level, -1);
+ xfs_trans_log_inode(cur->bc_tp, ip,
+ XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork));
+ cur->bc_nlevels--;
+out0:
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ return 0;
+}
+
+STATIC int
+xfs_btree_dec_cursor(
+ struct xfs_btree_cur *cur,
+ int level,
+ int *stat)
+{
+ int error;
+ int i;
+
+ if (level > 0) {
+ error = xfs_btree_decrement(cur, level, &i);
+ if (error)
+ return error;
+ }
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ *stat = 1;
+ return 0;
+}
+
+/*
+ * Single level of the btree record deletion routine.
+ * Delete record pointed to by cur/level.
+ * Remove the record from its block then rebalance the tree.
+ * Return 0 for error, 1 for done, 2 to go on to the next level.
+ */
+STATIC int /* error */
+xfs_btree_delrec(
+ struct xfs_btree_cur *cur, /* btree cursor */
+ int level, /* level removing record from */
+ int *stat) /* fail/done/go-on */
+{
+ struct xfs_btree_block *block; /* btree block */
+ union xfs_btree_ptr cptr; /* current block ptr */
+ struct xfs_buf *bp; /* buffer for block */
+ int error; /* error return value */
+ int i; /* loop counter */
+ union xfs_btree_key key; /* storage for keyp */
+ union xfs_btree_key *keyp = &key; /* passed to the next level */
+ union xfs_btree_ptr lptr; /* left sibling block ptr */
+ struct xfs_buf *lbp; /* left buffer pointer */
+ struct xfs_btree_block *left; /* left btree block */
+ int lrecs = 0; /* left record count */
+ int ptr; /* key/record index */
+ union xfs_btree_ptr rptr; /* right sibling block ptr */
+ struct xfs_buf *rbp; /* right buffer pointer */
+ struct xfs_btree_block *right; /* right btree block */
+ struct xfs_btree_block *rrblock; /* right-right btree block */
+ struct xfs_buf *rrbp; /* right-right buffer pointer */
+ int rrecs = 0; /* right record count */
+ struct xfs_btree_cur *tcur; /* temporary btree cursor */
+ int numrecs; /* temporary numrec count */
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+ XFS_BTREE_TRACE_ARGI(cur, level);
+
+ tcur = NULL;
+
+ /* Get the index of the entry being deleted, check for nothing there. */
+ ptr = cur->bc_ptrs[level];
+ if (ptr == 0) {
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ *stat = 0;
+ return 0;
+ }
+
+ /* Get the buffer & block containing the record or key/ptr. */
+ block = xfs_btree_get_block(cur, level, &bp);
+ numrecs = xfs_btree_get_numrecs(block);
+
+#ifdef DEBUG
+ error = xfs_btree_check_block(cur, block, level, bp);
+ if (error)
+ goto error0;
+#endif
+
+ /* Fail if we're off the end of the block. */
+ if (ptr > numrecs) {
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ *stat = 0;
+ return 0;
+ }
+
+ XFS_BTREE_STATS_INC(cur, delrec);
+ XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr);
+
+ /* Excise the entries being deleted. */
+ if (level > 0) {
+ /* It's a nonleaf. operate on keys and ptrs */
+ union xfs_btree_key *lkp;
+ union xfs_btree_ptr *lpp;
+
+ lkp = xfs_btree_key_addr(cur, ptr + 1, block);
+ lpp = xfs_btree_ptr_addr(cur, ptr + 1, block);
+
+#ifdef DEBUG
+ for (i = 0; i < numrecs - ptr; i++) {
+ error = xfs_btree_check_ptr(cur, lpp, i, level);
+ if (error)
+ goto error0;
+ }
+#endif
+
+ if (ptr < numrecs) {
+ xfs_btree_shift_keys(cur, lkp, -1, numrecs - ptr);
+ xfs_btree_shift_ptrs(cur, lpp, -1, numrecs - ptr);
+ xfs_btree_log_keys(cur, bp, ptr, numrecs - 1);
+ xfs_btree_log_ptrs(cur, bp, ptr, numrecs - 1);
+ }
+
+ /*
+ * If it's the first record in the block, we'll need to pass a
+ * key up to the next level (updkey).
+ */
+ if (ptr == 1)
+ keyp = xfs_btree_key_addr(cur, 1, block);
+ } else {
+ /* It's a leaf. operate on records */
+ if (ptr < numrecs) {
+ xfs_btree_shift_recs(cur,
+ xfs_btree_rec_addr(cur, ptr + 1, block),
+ -1, numrecs - ptr);
+ xfs_btree_log_recs(cur, bp, ptr, numrecs - 1);
+ }
+
+ /*
+ * If it's the first record in the block, we'll need a key
+ * structure to pass up to the next level (updkey).
+ */
+ if (ptr == 1) {
+ cur->bc_ops->init_key_from_rec(&key,
+ xfs_btree_rec_addr(cur, 1, block));
+ keyp = &key;
+ }
+ }
+
+ /*
+ * Decrement and log the number of entries in the block.
+ */
+ xfs_btree_set_numrecs(block, --numrecs);
+ xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS);
+
+ /*
+ * If we are tracking the last record in the tree and
+ * we are at the far right edge of the tree, update it.
+ */
+ if (xfs_btree_is_lastrec(cur, block, level)) {
+ cur->bc_ops->update_lastrec(cur, block, NULL,
+ ptr, LASTREC_DELREC);
+ }
+
+ /*
+ * We're at the root level. First, shrink the root block in-memory.
+ * Try to get rid of the next level down. If we can't then there's
+ * nothing left to do.
+ */
+ if (level == cur->bc_nlevels - 1) {
+ if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) {
+ xfs_iroot_realloc(cur->bc_private.b.ip, -1,
+ cur->bc_private.b.whichfork);
+
+ error = xfs_btree_kill_iroot(cur);
+ if (error)
+ goto error0;
+
+ error = xfs_btree_dec_cursor(cur, level, stat);
+ if (error)
+ goto error0;
+ *stat = 1;
+ return 0;
+ }
+
+ /*
+ * If this is the root level, and there's only one entry left,
+ * and it's NOT the leaf level, then we can get rid of this
+ * level.
+ */
+ if (numrecs == 1 && level > 0) {
+ union xfs_btree_ptr *pp;
+ /*
+ * pp is still set to the first pointer in the block.
+ * Make it the new root of the btree.
+ */
+ pp = xfs_btree_ptr_addr(cur, 1, block);
+ error = cur->bc_ops->kill_root(cur, bp, level, pp);
+ if (error)
+ goto error0;
+ } else if (level > 0) {
+ error = xfs_btree_dec_cursor(cur, level, stat);
+ if (error)
+ goto error0;
+ }
+ *stat = 1;
+ return 0;
+ }
+
+ /*
+ * If we deleted the leftmost entry in the block, update the
+ * key values above us in the tree.
+ */
+ if (ptr == 1) {
+ error = xfs_btree_updkey(cur, keyp, level + 1);
+ if (error)
+ goto error0;
+ }
+
+ /*
+ * If the number of records remaining in the block is at least
+ * the minimum, we're done.
+ */
+ if (numrecs >= cur->bc_ops->get_minrecs(cur, level)) {
+ error = xfs_btree_dec_cursor(cur, level, stat);
+ if (error)
+ goto error0;
+ return 0;
+ }
+
+ /*
+ * Otherwise, we have to move some records around to keep the
+ * tree balanced. Look at the left and right sibling blocks to
+ * see if we can re-balance by moving only one record.
+ */
+ xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
+ xfs_btree_get_sibling(cur, block, &lptr, XFS_BB_LEFTSIB);
+
+ if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) {
+ /*
+ * One child of root, need to get a chance to copy its contents
+ * into the root and delete it. Can't go up to next level,
+ * there's nothing to delete there.
+ */
+ if (xfs_btree_ptr_is_null(cur, &rptr) &&
+ xfs_btree_ptr_is_null(cur, &lptr) &&
+ level == cur->bc_nlevels - 2) {
+ error = xfs_btree_kill_iroot(cur);
+ if (!error)
+ error = xfs_btree_dec_cursor(cur, level, stat);
+ if (error)
+ goto error0;
+ return 0;
+ }
+ }
+
+ ASSERT(!xfs_btree_ptr_is_null(cur, &rptr) ||
+ !xfs_btree_ptr_is_null(cur, &lptr));
+
+ /*
+ * Duplicate the cursor so our btree manipulations here won't
+ * disrupt the next level up.
+ */
+ error = xfs_btree_dup_cursor(cur, &tcur);
+ if (error)
+ goto error0;
+
+ /*
+ * If there's a right sibling, see if it's ok to shift an entry
+ * out of it.
+ */
+ if (!xfs_btree_ptr_is_null(cur, &rptr)) {
+ /*
+ * Move the temp cursor to the last entry in the next block.
+ * Actually any entry but the first would suffice.
+ */
+ i = xfs_btree_lastrec(tcur, level);
+ XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
+
+ error = xfs_btree_increment(tcur, level, &i);
+ if (error)
+ goto error0;
+ XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
+
+ i = xfs_btree_lastrec(tcur, level);
+ XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
+
+ /* Grab a pointer to the block. */
+ right = xfs_btree_get_block(tcur, level, &rbp);
+#ifdef DEBUG
+ error = xfs_btree_check_block(tcur, right, level, rbp);
+ if (error)
+ goto error0;
+#endif
+ /* Grab the current block number, for future use. */
+ xfs_btree_get_sibling(tcur, right, &cptr, XFS_BB_LEFTSIB);
+
+ /*
+ * If right block is full enough so that removing one entry
+ * won't make it too empty, and left-shifting an entry out
+ * of right to us works, we're done.
+ */
+ if (xfs_btree_get_numrecs(right) - 1 >=
+ cur->bc_ops->get_minrecs(tcur, level)) {
+ error = xfs_btree_lshift(tcur, level, &i);
+ if (error)
+ goto error0;
+ if (i) {
+ ASSERT(xfs_btree_get_numrecs(block) >=
+ cur->bc_ops->get_minrecs(tcur, level));
+
+ xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
+ tcur = NULL;
+
+ error = xfs_btree_dec_cursor(cur, level, stat);
+ if (error)
+ goto error0;
+ return 0;
+ }
+ }
+
+ /*
+ * Otherwise, grab the number of records in right for
+ * future reference, and fix up the temp cursor to point
+ * to our block again (last record).
+ */
+ rrecs = xfs_btree_get_numrecs(right);
+ if (!xfs_btree_ptr_is_null(cur, &lptr)) {
+ i = xfs_btree_firstrec(tcur, level);
+ XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
+
+ error = xfs_btree_decrement(tcur, level, &i);
+ if (error)
+ goto error0;
+ XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
+ }
+ }
+
+ /*
+ * If there's a left sibling, see if it's ok to shift an entry
+ * out of it.
+ */
+ if (!xfs_btree_ptr_is_null(cur, &lptr)) {
+ /*
+ * Move the temp cursor to the first entry in the
+ * previous block.
+ */
+ i = xfs_btree_firstrec(tcur, level);
+ XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
+
+ error = xfs_btree_decrement(tcur, level, &i);
+ if (error)
+ goto error0;
+ i = xfs_btree_firstrec(tcur, level);
+ XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
+
+ /* Grab a pointer to the block. */
+ left = xfs_btree_get_block(tcur, level, &lbp);
+#ifdef DEBUG
+ error = xfs_btree_check_block(cur, left, level, lbp);
+ if (error)
+ goto error0;
+#endif
+ /* Grab the current block number, for future use. */
+ xfs_btree_get_sibling(tcur, left, &cptr, XFS_BB_RIGHTSIB);
+
+ /*
+ * If left block is full enough so that removing one entry
+ * won't make it too empty, and right-shifting an entry out
+ * of left to us works, we're done.
+ */
+ if (xfs_btree_get_numrecs(left) - 1 >=
+ cur->bc_ops->get_minrecs(tcur, level)) {
+ error = xfs_btree_rshift(tcur, level, &i);
+ if (error)
+ goto error0;
+ if (i) {
+ ASSERT(xfs_btree_get_numrecs(block) >=
+ cur->bc_ops->get_minrecs(tcur, level));
+ xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
+ tcur = NULL;
+ if (level == 0)
+ cur->bc_ptrs[0]++;
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ *stat = 1;
+ return 0;
+ }
+ }
+
+ /*
+ * Otherwise, grab the number of records in right for
+ * future reference.
+ */
+ lrecs = xfs_btree_get_numrecs(left);
+ }
+
+ /* Delete the temp cursor, we're done with it. */
+ xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
+ tcur = NULL;
+
+ /* If here, we need to do a join to keep the tree balanced. */
+ ASSERT(!xfs_btree_ptr_is_null(cur, &cptr));
+
+ if (!xfs_btree_ptr_is_null(cur, &lptr) &&
+ lrecs + xfs_btree_get_numrecs(block) <=
+ cur->bc_ops->get_maxrecs(cur, level)) {
+ /*
+ * Set "right" to be the starting block,
+ * "left" to be the left neighbor.
+ */
+ rptr = cptr;
+ right = block;
+ rbp = bp;
+ error = xfs_btree_read_buf_block(cur, &lptr, level,
+ 0, &left, &lbp);
+ if (error)
+ goto error0;
+
+ /*
+ * If that won't work, see if we can join with the right neighbor block.
+ */
+ } else if (!xfs_btree_ptr_is_null(cur, &rptr) &&
+ rrecs + xfs_btree_get_numrecs(block) <=
+ cur->bc_ops->get_maxrecs(cur, level)) {
+ /*
+ * Set "left" to be the starting block,
+ * "right" to be the right neighbor.
+ */
+ lptr = cptr;
+ left = block;
+ lbp = bp;
+ error = xfs_btree_read_buf_block(cur, &rptr, level,
+ 0, &right, &rbp);
+ if (error)
+ goto error0;
+
+ /*
+ * Otherwise, we can't fix the imbalance.
+ * Just return. This is probably a logic error, but it's not fatal.
+ */
+ } else {
+ error = xfs_btree_dec_cursor(cur, level, stat);
+ if (error)
+ goto error0;
+ return 0;
+ }
+
+ rrecs = xfs_btree_get_numrecs(right);
+ lrecs = xfs_btree_get_numrecs(left);
+
+ /*
+ * We're now going to join "left" and "right" by moving all the stuff
+ * in "right" to "left" and deleting "right".
+ */
+ XFS_BTREE_STATS_ADD(cur, moves, rrecs);
+ 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 */
+ union xfs_btree_key *rkp; /* right btree key */
+ union xfs_btree_ptr *rpp; /* right address pointer */
+
+ lkp = xfs_btree_key_addr(cur, lrecs + 1, left);
+ lpp = xfs_btree_ptr_addr(cur, lrecs + 1, left);
+ rkp = xfs_btree_key_addr(cur, 1, right);
+ rpp = xfs_btree_ptr_addr(cur, 1, right);
+#ifdef DEBUG
+ for (i = 1; i < rrecs; i++) {
+ error = xfs_btree_check_ptr(cur, rpp, i, level);
+ if (error)
+ goto error0;
+ }
+#endif
+ xfs_btree_copy_keys(cur, lkp, rkp, rrecs);
+ xfs_btree_copy_ptrs(cur, lpp, rpp, rrecs);
+
+ xfs_btree_log_keys(cur, lbp, lrecs + 1, lrecs + rrecs);
+ xfs_btree_log_ptrs(cur, lbp, lrecs + 1, lrecs + rrecs);
+ } else {
+ /* It's a leaf. Move records. */
+ union xfs_btree_rec *lrp; /* left record pointer */
+ union xfs_btree_rec *rrp; /* right record pointer */
+
+ lrp = xfs_btree_rec_addr(cur, lrecs + 1, left);
+ rrp = xfs_btree_rec_addr(cur, 1, right);
+
+ xfs_btree_copy_recs(cur, lrp, rrp, rrecs);
+ xfs_btree_log_recs(cur, lbp, lrecs + 1, lrecs + rrecs);
+ }
+
+ XFS_BTREE_STATS_INC(cur, join);
+
+ /*
+ * Fix up the number of records and right block pointer in the
+ * surviving block, and log it.
+ */
+ xfs_btree_set_numrecs(left, lrecs + rrecs);
+ xfs_btree_get_sibling(cur, right, &cptr, XFS_BB_RIGHTSIB),
+ xfs_btree_set_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB);
+ xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
+
+ /* If there is a right sibling, point it to the remaining block. */
+ xfs_btree_get_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB);
+ if (!xfs_btree_ptr_is_null(cur, &cptr)) {
+ error = xfs_btree_read_buf_block(cur, &cptr, level,
+ 0, &rrblock, &rrbp);
+ if (error)
+ goto error0;
+ xfs_btree_set_sibling(cur, rrblock, &lptr, XFS_BB_LEFTSIB);
+ xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB);
+ }
+
+ /* Free the deleted block. */
+ error = cur->bc_ops->free_block(cur, rbp);
+ if (error)
+ goto error0;
+ XFS_BTREE_STATS_INC(cur, free);
+
+ /*
+ * If we joined with the left neighbor, set the buffer in the
+ * cursor to the left block, and fix up the index.
+ */
+ if (bp != lbp) {
+ cur->bc_bufs[level] = lbp;
+ cur->bc_ptrs[level] += lrecs;
+ cur->bc_ra[level] = 0;
+ }
+ /*
+ * If we joined with the right neighbor and there's a level above
+ * us, increment the cursor at that level.
+ */
+ else if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) ||
+ (level + 1 < cur->bc_nlevels)) {
+ error = xfs_btree_increment(cur, level + 1, &i);
+ if (error)
+ goto error0;
+ }
+
+ /*
+ * Readjust the ptr at this level if it's not a leaf, since it's
+ * still pointing at the deletion point, which makes the cursor
+ * inconsistent. If this makes the ptr 0, the caller fixes it up.
+ * We can't use decrement because it would change the next level up.
+ */
+ if (level > 0)
+ cur->bc_ptrs[level]--;
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ /* Return value means the next level up has something to do. */
+ *stat = 2;
+ return 0;
+
+error0:
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
+ if (tcur)
+ xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
+ return error;
+}
+
+/*
+ * Delete the record pointed to by cur.
+ * The cursor refers to the place where the record was (could be inserted)
+ * when the operation returns.
+ */
+int /* error */
+xfs_btree_delete(
+ struct xfs_btree_cur *cur,
+ int *stat) /* success/failure */
+{
+ int error; /* error return value */
+ int level;
+ int i;
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
+
+ /*
+ * Go up the tree, starting at leaf level.
+ *
+ * If 2 is returned then a join was done; go to the next level.
+ * Otherwise we are done.
+ */
+ for (level = 0, i = 2; i == 2; level++) {
+ error = xfs_btree_delrec(cur, level, &i);
+ if (error)
+ goto error0;
+ }
+
+ if (i == 0) {
+ for (level = 1; level < cur->bc_nlevels; level++) {
+ if (cur->bc_ptrs[level] == 0) {
+ error = xfs_btree_decrement(cur, level, &i);
+ if (error)
+ goto error0;
+ break;
+ }
+ }
+ }
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ *stat = i;
+ return 0;
+error0:
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
+ return error;
+}
+
+/*
+ * Get the data from the pointed-to record.
+ */
+int /* error */
+xfs_btree_get_rec(
+ struct xfs_btree_cur *cur, /* btree cursor */
+ union xfs_btree_rec **recp, /* output: btree record */
+ int *stat) /* output: success/failure */
+{
+ struct xfs_btree_block *block; /* btree block */
+ struct xfs_buf *bp; /* buffer pointer */
+ int ptr; /* record number */
+#ifdef DEBUG
+ int error; /* error return value */
+#endif
+
+ ptr = cur->bc_ptrs[0];
+ block = xfs_btree_get_block(cur, 0, &bp);
+
+#ifdef DEBUG
+ error = xfs_btree_check_block(cur, block, 0, bp);
+ if (error)
+ return error;
+#endif
+
+ /*
+ * Off the right end or left end, return failure.
+ */
+ if (ptr > xfs_btree_get_numrecs(block) || ptr <= 0) {
+ *stat = 0;
+ return 0;
+ }
+
+ /*
+ * Point to the record and extract its data.
+ */
+ *recp = xfs_btree_rec_addr(cur, ptr, block);
+ *stat = 1;
+ return 0;
+}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff