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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /fs/xfs/libxfs/xfs_bmap_btree.c
Initial import
Diffstat (limited to 'fs/xfs/libxfs/xfs_bmap_btree.c')
-rw-r--r--fs/xfs/libxfs/xfs_bmap_btree.c883
1 files changed, 883 insertions, 0 deletions
diff --git a/fs/xfs/libxfs/xfs_bmap_btree.c b/fs/xfs/libxfs/xfs_bmap_btree.c
new file mode 100644
index 000000000..2c44c8e50
--- /dev/null
+++ b/fs/xfs/libxfs/xfs_bmap_btree.c
@@ -0,0 +1,883 @@
+/*
+ * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_shared.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_bit.h"
+#include "xfs_mount.h"
+#include "xfs_inode.h"
+#include "xfs_trans.h"
+#include "xfs_inode_item.h"
+#include "xfs_alloc.h"
+#include "xfs_btree.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_bmap.h"
+#include "xfs_error.h"
+#include "xfs_quota.h"
+#include "xfs_trace.h"
+#include "xfs_cksum.h"
+
+/*
+ * Determine the extent state.
+ */
+/* ARGSUSED */
+STATIC xfs_exntst_t
+xfs_extent_state(
+ xfs_filblks_t blks,
+ int extent_flag)
+{
+ if (extent_flag) {
+ ASSERT(blks != 0); /* saved for DMIG */
+ return XFS_EXT_UNWRITTEN;
+ }
+ return XFS_EXT_NORM;
+}
+
+/*
+ * Convert on-disk form of btree root to in-memory form.
+ */
+void
+xfs_bmdr_to_bmbt(
+ struct xfs_inode *ip,
+ xfs_bmdr_block_t *dblock,
+ int dblocklen,
+ struct xfs_btree_block *rblock,
+ int rblocklen)
+{
+ struct xfs_mount *mp = ip->i_mount;
+ int dmxr;
+ xfs_bmbt_key_t *fkp;
+ __be64 *fpp;
+ xfs_bmbt_key_t *tkp;
+ __be64 *tpp;
+
+ if (xfs_sb_version_hascrc(&mp->m_sb))
+ xfs_btree_init_block_int(mp, rblock, XFS_BUF_DADDR_NULL,
+ XFS_BMAP_CRC_MAGIC, 0, 0, ip->i_ino,
+ XFS_BTREE_LONG_PTRS | XFS_BTREE_CRC_BLOCKS);
+ else
+ xfs_btree_init_block_int(mp, rblock, XFS_BUF_DADDR_NULL,
+ XFS_BMAP_MAGIC, 0, 0, ip->i_ino,
+ XFS_BTREE_LONG_PTRS);
+
+ rblock->bb_level = dblock->bb_level;
+ ASSERT(be16_to_cpu(rblock->bb_level) > 0);
+ rblock->bb_numrecs = dblock->bb_numrecs;
+ dmxr = xfs_bmdr_maxrecs(dblocklen, 0);
+ fkp = XFS_BMDR_KEY_ADDR(dblock, 1);
+ tkp = XFS_BMBT_KEY_ADDR(mp, rblock, 1);
+ fpp = XFS_BMDR_PTR_ADDR(dblock, 1, dmxr);
+ tpp = XFS_BMAP_BROOT_PTR_ADDR(mp, rblock, 1, rblocklen);
+ dmxr = be16_to_cpu(dblock->bb_numrecs);
+ memcpy(tkp, fkp, sizeof(*fkp) * dmxr);
+ memcpy(tpp, fpp, sizeof(*fpp) * dmxr);
+}
+
+/*
+ * Convert a compressed bmap extent record to an uncompressed form.
+ * This code must be in sync with the routines xfs_bmbt_get_startoff,
+ * xfs_bmbt_get_startblock, xfs_bmbt_get_blockcount and xfs_bmbt_get_state.
+ */
+STATIC void
+__xfs_bmbt_get_all(
+ __uint64_t l0,
+ __uint64_t l1,
+ xfs_bmbt_irec_t *s)
+{
+ int ext_flag;
+ xfs_exntst_t st;
+
+ ext_flag = (int)(l0 >> (64 - BMBT_EXNTFLAG_BITLEN));
+ s->br_startoff = ((xfs_fileoff_t)l0 &
+ xfs_mask64lo(64 - BMBT_EXNTFLAG_BITLEN)) >> 9;
+ s->br_startblock = (((xfs_fsblock_t)l0 & xfs_mask64lo(9)) << 43) |
+ (((xfs_fsblock_t)l1) >> 21);
+ s->br_blockcount = (xfs_filblks_t)(l1 & xfs_mask64lo(21));
+ /* This is xfs_extent_state() in-line */
+ if (ext_flag) {
+ ASSERT(s->br_blockcount != 0); /* saved for DMIG */
+ st = XFS_EXT_UNWRITTEN;
+ } else
+ st = XFS_EXT_NORM;
+ s->br_state = st;
+}
+
+void
+xfs_bmbt_get_all(
+ xfs_bmbt_rec_host_t *r,
+ xfs_bmbt_irec_t *s)
+{
+ __xfs_bmbt_get_all(r->l0, r->l1, s);
+}
+
+/*
+ * Extract the blockcount field from an in memory bmap extent record.
+ */
+xfs_filblks_t
+xfs_bmbt_get_blockcount(
+ xfs_bmbt_rec_host_t *r)
+{
+ return (xfs_filblks_t)(r->l1 & xfs_mask64lo(21));
+}
+
+/*
+ * Extract the startblock field from an in memory bmap extent record.
+ */
+xfs_fsblock_t
+xfs_bmbt_get_startblock(
+ xfs_bmbt_rec_host_t *r)
+{
+ return (((xfs_fsblock_t)r->l0 & xfs_mask64lo(9)) << 43) |
+ (((xfs_fsblock_t)r->l1) >> 21);
+}
+
+/*
+ * Extract the startoff field from an in memory bmap extent record.
+ */
+xfs_fileoff_t
+xfs_bmbt_get_startoff(
+ xfs_bmbt_rec_host_t *r)
+{
+ return ((xfs_fileoff_t)r->l0 &
+ xfs_mask64lo(64 - BMBT_EXNTFLAG_BITLEN)) >> 9;
+}
+
+xfs_exntst_t
+xfs_bmbt_get_state(
+ xfs_bmbt_rec_host_t *r)
+{
+ int ext_flag;
+
+ ext_flag = (int)((r->l0) >> (64 - BMBT_EXNTFLAG_BITLEN));
+ return xfs_extent_state(xfs_bmbt_get_blockcount(r),
+ ext_flag);
+}
+
+/*
+ * Extract the blockcount field from an on disk bmap extent record.
+ */
+xfs_filblks_t
+xfs_bmbt_disk_get_blockcount(
+ xfs_bmbt_rec_t *r)
+{
+ return (xfs_filblks_t)(be64_to_cpu(r->l1) & xfs_mask64lo(21));
+}
+
+/*
+ * Extract the startoff field from a disk format bmap extent record.
+ */
+xfs_fileoff_t
+xfs_bmbt_disk_get_startoff(
+ xfs_bmbt_rec_t *r)
+{
+ return ((xfs_fileoff_t)be64_to_cpu(r->l0) &
+ xfs_mask64lo(64 - BMBT_EXNTFLAG_BITLEN)) >> 9;
+}
+
+
+/*
+ * Set all the fields in a bmap extent record from the arguments.
+ */
+void
+xfs_bmbt_set_allf(
+ xfs_bmbt_rec_host_t *r,
+ xfs_fileoff_t startoff,
+ xfs_fsblock_t startblock,
+ xfs_filblks_t blockcount,
+ xfs_exntst_t state)
+{
+ int extent_flag = (state == XFS_EXT_NORM) ? 0 : 1;
+
+ ASSERT(state == XFS_EXT_NORM || state == XFS_EXT_UNWRITTEN);
+ ASSERT((startoff & xfs_mask64hi(64-BMBT_STARTOFF_BITLEN)) == 0);
+ ASSERT((blockcount & xfs_mask64hi(64-BMBT_BLOCKCOUNT_BITLEN)) == 0);
+
+ ASSERT((startblock & xfs_mask64hi(64-BMBT_STARTBLOCK_BITLEN)) == 0);
+
+ r->l0 = ((xfs_bmbt_rec_base_t)extent_flag << 63) |
+ ((xfs_bmbt_rec_base_t)startoff << 9) |
+ ((xfs_bmbt_rec_base_t)startblock >> 43);
+ r->l1 = ((xfs_bmbt_rec_base_t)startblock << 21) |
+ ((xfs_bmbt_rec_base_t)blockcount &
+ (xfs_bmbt_rec_base_t)xfs_mask64lo(21));
+}
+
+/*
+ * Set all the fields in a bmap extent record from the uncompressed form.
+ */
+void
+xfs_bmbt_set_all(
+ xfs_bmbt_rec_host_t *r,
+ xfs_bmbt_irec_t *s)
+{
+ xfs_bmbt_set_allf(r, s->br_startoff, s->br_startblock,
+ s->br_blockcount, s->br_state);
+}
+
+
+/*
+ * Set all the fields in a disk format bmap extent record from the arguments.
+ */
+void
+xfs_bmbt_disk_set_allf(
+ xfs_bmbt_rec_t *r,
+ xfs_fileoff_t startoff,
+ xfs_fsblock_t startblock,
+ xfs_filblks_t blockcount,
+ xfs_exntst_t state)
+{
+ int extent_flag = (state == XFS_EXT_NORM) ? 0 : 1;
+
+ ASSERT(state == XFS_EXT_NORM || state == XFS_EXT_UNWRITTEN);
+ ASSERT((startoff & xfs_mask64hi(64-BMBT_STARTOFF_BITLEN)) == 0);
+ ASSERT((blockcount & xfs_mask64hi(64-BMBT_BLOCKCOUNT_BITLEN)) == 0);
+ ASSERT((startblock & xfs_mask64hi(64-BMBT_STARTBLOCK_BITLEN)) == 0);
+
+ r->l0 = cpu_to_be64(
+ ((xfs_bmbt_rec_base_t)extent_flag << 63) |
+ ((xfs_bmbt_rec_base_t)startoff << 9) |
+ ((xfs_bmbt_rec_base_t)startblock >> 43));
+ r->l1 = cpu_to_be64(
+ ((xfs_bmbt_rec_base_t)startblock << 21) |
+ ((xfs_bmbt_rec_base_t)blockcount &
+ (xfs_bmbt_rec_base_t)xfs_mask64lo(21)));
+}
+
+/*
+ * Set all the fields in a bmap extent record from the uncompressed form.
+ */
+STATIC void
+xfs_bmbt_disk_set_all(
+ xfs_bmbt_rec_t *r,
+ xfs_bmbt_irec_t *s)
+{
+ xfs_bmbt_disk_set_allf(r, s->br_startoff, s->br_startblock,
+ s->br_blockcount, s->br_state);
+}
+
+/*
+ * Set the blockcount field in a bmap extent record.
+ */
+void
+xfs_bmbt_set_blockcount(
+ xfs_bmbt_rec_host_t *r,
+ xfs_filblks_t v)
+{
+ ASSERT((v & xfs_mask64hi(43)) == 0);
+ r->l1 = (r->l1 & (xfs_bmbt_rec_base_t)xfs_mask64hi(43)) |
+ (xfs_bmbt_rec_base_t)(v & xfs_mask64lo(21));
+}
+
+/*
+ * Set the startblock field in a bmap extent record.
+ */
+void
+xfs_bmbt_set_startblock(
+ xfs_bmbt_rec_host_t *r,
+ xfs_fsblock_t v)
+{
+ ASSERT((v & xfs_mask64hi(12)) == 0);
+ r->l0 = (r->l0 & (xfs_bmbt_rec_base_t)xfs_mask64hi(55)) |
+ (xfs_bmbt_rec_base_t)(v >> 43);
+ r->l1 = (r->l1 & (xfs_bmbt_rec_base_t)xfs_mask64lo(21)) |
+ (xfs_bmbt_rec_base_t)(v << 21);
+}
+
+/*
+ * Set the startoff field in a bmap extent record.
+ */
+void
+xfs_bmbt_set_startoff(
+ xfs_bmbt_rec_host_t *r,
+ xfs_fileoff_t v)
+{
+ ASSERT((v & xfs_mask64hi(9)) == 0);
+ r->l0 = (r->l0 & (xfs_bmbt_rec_base_t) xfs_mask64hi(1)) |
+ ((xfs_bmbt_rec_base_t)v << 9) |
+ (r->l0 & (xfs_bmbt_rec_base_t)xfs_mask64lo(9));
+}
+
+/*
+ * Set the extent state field in a bmap extent record.
+ */
+void
+xfs_bmbt_set_state(
+ xfs_bmbt_rec_host_t *r,
+ xfs_exntst_t v)
+{
+ ASSERT(v == XFS_EXT_NORM || v == XFS_EXT_UNWRITTEN);
+ if (v == XFS_EXT_NORM)
+ r->l0 &= xfs_mask64lo(64 - BMBT_EXNTFLAG_BITLEN);
+ else
+ r->l0 |= xfs_mask64hi(BMBT_EXNTFLAG_BITLEN);
+}
+
+/*
+ * Convert in-memory form of btree root to on-disk form.
+ */
+void
+xfs_bmbt_to_bmdr(
+ struct xfs_mount *mp,
+ struct xfs_btree_block *rblock,
+ int rblocklen,
+ xfs_bmdr_block_t *dblock,
+ int dblocklen)
+{
+ int dmxr;
+ xfs_bmbt_key_t *fkp;
+ __be64 *fpp;
+ xfs_bmbt_key_t *tkp;
+ __be64 *tpp;
+
+ if (xfs_sb_version_hascrc(&mp->m_sb)) {
+ ASSERT(rblock->bb_magic == cpu_to_be32(XFS_BMAP_CRC_MAGIC));
+ ASSERT(uuid_equal(&rblock->bb_u.l.bb_uuid, &mp->m_sb.sb_uuid));
+ ASSERT(rblock->bb_u.l.bb_blkno ==
+ cpu_to_be64(XFS_BUF_DADDR_NULL));
+ } else
+ ASSERT(rblock->bb_magic == cpu_to_be32(XFS_BMAP_MAGIC));
+ ASSERT(rblock->bb_u.l.bb_leftsib == cpu_to_be64(NULLFSBLOCK));
+ ASSERT(rblock->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK));
+ ASSERT(rblock->bb_level != 0);
+ dblock->bb_level = rblock->bb_level;
+ dblock->bb_numrecs = rblock->bb_numrecs;
+ dmxr = xfs_bmdr_maxrecs(dblocklen, 0);
+ fkp = XFS_BMBT_KEY_ADDR(mp, rblock, 1);
+ tkp = XFS_BMDR_KEY_ADDR(dblock, 1);
+ fpp = XFS_BMAP_BROOT_PTR_ADDR(mp, rblock, 1, rblocklen);
+ tpp = XFS_BMDR_PTR_ADDR(dblock, 1, dmxr);
+ dmxr = be16_to_cpu(dblock->bb_numrecs);
+ memcpy(tkp, fkp, sizeof(*fkp) * dmxr);
+ memcpy(tpp, fpp, sizeof(*fpp) * dmxr);
+}
+
+/*
+ * Check extent records, which have just been read, for
+ * any bit in the extent flag field. ASSERT on debug
+ * kernels, as this condition should not occur.
+ * Return an error condition (1) if any flags found,
+ * otherwise return 0.
+ */
+
+int
+xfs_check_nostate_extents(
+ xfs_ifork_t *ifp,
+ xfs_extnum_t idx,
+ xfs_extnum_t num)
+{
+ for (; num > 0; num--, idx++) {
+ xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, idx);
+ if ((ep->l0 >>
+ (64 - BMBT_EXNTFLAG_BITLEN)) != 0) {
+ ASSERT(0);
+ return 1;
+ }
+ }
+ return 0;
+}
+
+
+STATIC struct xfs_btree_cur *
+xfs_bmbt_dup_cursor(
+ struct xfs_btree_cur *cur)
+{
+ struct xfs_btree_cur *new;
+
+ new = xfs_bmbt_init_cursor(cur->bc_mp, cur->bc_tp,
+ cur->bc_private.b.ip, cur->bc_private.b.whichfork);
+
+ /*
+ * Copy the firstblock, flist, and flags values,
+ * since init cursor doesn't get them.
+ */
+ new->bc_private.b.firstblock = cur->bc_private.b.firstblock;
+ new->bc_private.b.flist = cur->bc_private.b.flist;
+ new->bc_private.b.flags = cur->bc_private.b.flags;
+
+ return new;
+}
+
+STATIC void
+xfs_bmbt_update_cursor(
+ struct xfs_btree_cur *src,
+ struct xfs_btree_cur *dst)
+{
+ ASSERT((dst->bc_private.b.firstblock != NULLFSBLOCK) ||
+ (dst->bc_private.b.ip->i_d.di_flags & XFS_DIFLAG_REALTIME));
+ ASSERT(dst->bc_private.b.flist == src->bc_private.b.flist);
+
+ dst->bc_private.b.allocated += src->bc_private.b.allocated;
+ dst->bc_private.b.firstblock = src->bc_private.b.firstblock;
+
+ src->bc_private.b.allocated = 0;
+}
+
+STATIC int
+xfs_bmbt_alloc_block(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_ptr *start,
+ union xfs_btree_ptr *new,
+ int *stat)
+{
+ xfs_alloc_arg_t args; /* block allocation args */
+ int error; /* error return value */
+
+ memset(&args, 0, sizeof(args));
+ args.tp = cur->bc_tp;
+ args.mp = cur->bc_mp;
+ args.fsbno = cur->bc_private.b.firstblock;
+ args.firstblock = args.fsbno;
+
+ if (args.fsbno == NULLFSBLOCK) {
+ args.fsbno = be64_to_cpu(start->l);
+ args.type = XFS_ALLOCTYPE_START_BNO;
+ /*
+ * Make sure there is sufficient room left in the AG to
+ * complete a full tree split for an extent insert. If
+ * we are converting the middle part of an extent then
+ * we may need space for two tree splits.
+ *
+ * We are relying on the caller to make the correct block
+ * reservation for this operation to succeed. If the
+ * reservation amount is insufficient then we may fail a
+ * block allocation here and corrupt the filesystem.
+ */
+ args.minleft = xfs_trans_get_block_res(args.tp);
+ } else if (cur->bc_private.b.flist->xbf_low) {
+ args.type = XFS_ALLOCTYPE_START_BNO;
+ } else {
+ args.type = XFS_ALLOCTYPE_NEAR_BNO;
+ }
+
+ args.minlen = args.maxlen = args.prod = 1;
+ args.wasdel = cur->bc_private.b.flags & XFS_BTCUR_BPRV_WASDEL;
+ if (!args.wasdel && xfs_trans_get_block_res(args.tp) == 0) {
+ error = -ENOSPC;
+ goto error0;
+ }
+ error = xfs_alloc_vextent(&args);
+ if (error)
+ goto error0;
+
+ if (args.fsbno == NULLFSBLOCK && args.minleft) {
+ /*
+ * Could not find an AG with enough free space to satisfy
+ * a full btree split. Try again without minleft and if
+ * successful activate the lowspace algorithm.
+ */
+ args.fsbno = 0;
+ args.type = XFS_ALLOCTYPE_FIRST_AG;
+ args.minleft = 0;
+ error = xfs_alloc_vextent(&args);
+ if (error)
+ goto error0;
+ cur->bc_private.b.flist->xbf_low = 1;
+ }
+ if (args.fsbno == NULLFSBLOCK) {
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ *stat = 0;
+ return 0;
+ }
+ ASSERT(args.len == 1);
+ cur->bc_private.b.firstblock = args.fsbno;
+ cur->bc_private.b.allocated++;
+ cur->bc_private.b.ip->i_d.di_nblocks++;
+ xfs_trans_log_inode(args.tp, cur->bc_private.b.ip, XFS_ILOG_CORE);
+ xfs_trans_mod_dquot_byino(args.tp, cur->bc_private.b.ip,
+ XFS_TRANS_DQ_BCOUNT, 1L);
+
+ new->l = cpu_to_be64(args.fsbno);
+
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
+ *stat = 1;
+ return 0;
+
+ error0:
+ XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
+ return error;
+}
+
+STATIC int
+xfs_bmbt_free_block(
+ struct xfs_btree_cur *cur,
+ struct xfs_buf *bp)
+{
+ struct xfs_mount *mp = cur->bc_mp;
+ struct xfs_inode *ip = cur->bc_private.b.ip;
+ struct xfs_trans *tp = cur->bc_tp;
+ xfs_fsblock_t fsbno = XFS_DADDR_TO_FSB(mp, XFS_BUF_ADDR(bp));
+
+ xfs_bmap_add_free(fsbno, 1, cur->bc_private.b.flist, mp);
+ ip->i_d.di_nblocks--;
+
+ xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
+ xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, -1L);
+ xfs_trans_binval(tp, bp);
+ return 0;
+}
+
+STATIC int
+xfs_bmbt_get_minrecs(
+ struct xfs_btree_cur *cur,
+ int level)
+{
+ if (level == cur->bc_nlevels - 1) {
+ struct xfs_ifork *ifp;
+
+ ifp = XFS_IFORK_PTR(cur->bc_private.b.ip,
+ cur->bc_private.b.whichfork);
+
+ return xfs_bmbt_maxrecs(cur->bc_mp,
+ ifp->if_broot_bytes, level == 0) / 2;
+ }
+
+ return cur->bc_mp->m_bmap_dmnr[level != 0];
+}
+
+int
+xfs_bmbt_get_maxrecs(
+ struct xfs_btree_cur *cur,
+ int level)
+{
+ if (level == cur->bc_nlevels - 1) {
+ struct xfs_ifork *ifp;
+
+ ifp = XFS_IFORK_PTR(cur->bc_private.b.ip,
+ cur->bc_private.b.whichfork);
+
+ return xfs_bmbt_maxrecs(cur->bc_mp,
+ ifp->if_broot_bytes, level == 0);
+ }
+
+ return cur->bc_mp->m_bmap_dmxr[level != 0];
+
+}
+
+/*
+ * Get the maximum records we could store in the on-disk format.
+ *
+ * For non-root nodes this is equivalent to xfs_bmbt_get_maxrecs, but
+ * for the root node this checks the available space in the dinode fork
+ * so that we can resize the in-memory buffer to match it. After a
+ * resize to the maximum size this function returns the same value
+ * as xfs_bmbt_get_maxrecs for the root node, too.
+ */
+STATIC int
+xfs_bmbt_get_dmaxrecs(
+ struct xfs_btree_cur *cur,
+ int level)
+{
+ if (level != cur->bc_nlevels - 1)
+ return cur->bc_mp->m_bmap_dmxr[level != 0];
+ return xfs_bmdr_maxrecs(cur->bc_private.b.forksize, level == 0);
+}
+
+STATIC void
+xfs_bmbt_init_key_from_rec(
+ union xfs_btree_key *key,
+ union xfs_btree_rec *rec)
+{
+ key->bmbt.br_startoff =
+ cpu_to_be64(xfs_bmbt_disk_get_startoff(&rec->bmbt));
+}
+
+STATIC void
+xfs_bmbt_init_rec_from_key(
+ union xfs_btree_key *key,
+ union xfs_btree_rec *rec)
+{
+ ASSERT(key->bmbt.br_startoff != 0);
+
+ xfs_bmbt_disk_set_allf(&rec->bmbt, be64_to_cpu(key->bmbt.br_startoff),
+ 0, 0, XFS_EXT_NORM);
+}
+
+STATIC void
+xfs_bmbt_init_rec_from_cur(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_rec *rec)
+{
+ xfs_bmbt_disk_set_all(&rec->bmbt, &cur->bc_rec.b);
+}
+
+STATIC void
+xfs_bmbt_init_ptr_from_cur(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_ptr *ptr)
+{
+ ptr->l = 0;
+}
+
+STATIC __int64_t
+xfs_bmbt_key_diff(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_key *key)
+{
+ return (__int64_t)be64_to_cpu(key->bmbt.br_startoff) -
+ cur->bc_rec.b.br_startoff;
+}
+
+static bool
+xfs_bmbt_verify(
+ struct xfs_buf *bp)
+{
+ struct xfs_mount *mp = bp->b_target->bt_mount;
+ struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
+ unsigned int level;
+
+ switch (block->bb_magic) {
+ case cpu_to_be32(XFS_BMAP_CRC_MAGIC):
+ if (!xfs_sb_version_hascrc(&mp->m_sb))
+ return false;
+ if (!uuid_equal(&block->bb_u.l.bb_uuid, &mp->m_sb.sb_uuid))
+ return false;
+ if (be64_to_cpu(block->bb_u.l.bb_blkno) != bp->b_bn)
+ return false;
+ /*
+ * XXX: need a better way of verifying the owner here. Right now
+ * just make sure there has been one set.
+ */
+ if (be64_to_cpu(block->bb_u.l.bb_owner) == 0)
+ return false;
+ /* fall through */
+ case cpu_to_be32(XFS_BMAP_MAGIC):
+ break;
+ default:
+ return false;
+ }
+
+ /*
+ * numrecs and level verification.
+ *
+ * We don't know what fork we belong to, so just verify that the level
+ * is less than the maximum of the two. Later checks will be more
+ * precise.
+ */
+ level = be16_to_cpu(block->bb_level);
+ if (level > max(mp->m_bm_maxlevels[0], mp->m_bm_maxlevels[1]))
+ return false;
+ if (be16_to_cpu(block->bb_numrecs) > mp->m_bmap_dmxr[level != 0])
+ return false;
+
+ /* sibling pointer verification */
+ if (!block->bb_u.l.bb_leftsib ||
+ (block->bb_u.l.bb_leftsib != cpu_to_be64(NULLFSBLOCK) &&
+ !XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_u.l.bb_leftsib))))
+ return false;
+ if (!block->bb_u.l.bb_rightsib ||
+ (block->bb_u.l.bb_rightsib != cpu_to_be64(NULLFSBLOCK) &&
+ !XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_u.l.bb_rightsib))))
+ return false;
+
+ return true;
+}
+
+static void
+xfs_bmbt_read_verify(
+ struct xfs_buf *bp)
+{
+ if (!xfs_btree_lblock_verify_crc(bp))
+ xfs_buf_ioerror(bp, -EFSBADCRC);
+ else if (!xfs_bmbt_verify(bp))
+ xfs_buf_ioerror(bp, -EFSCORRUPTED);
+
+ if (bp->b_error) {
+ trace_xfs_btree_corrupt(bp, _RET_IP_);
+ xfs_verifier_error(bp);
+ }
+}
+
+static void
+xfs_bmbt_write_verify(
+ struct xfs_buf *bp)
+{
+ if (!xfs_bmbt_verify(bp)) {
+ trace_xfs_btree_corrupt(bp, _RET_IP_);
+ xfs_buf_ioerror(bp, -EFSCORRUPTED);
+ xfs_verifier_error(bp);
+ return;
+ }
+ xfs_btree_lblock_calc_crc(bp);
+}
+
+const struct xfs_buf_ops xfs_bmbt_buf_ops = {
+ .verify_read = xfs_bmbt_read_verify,
+ .verify_write = xfs_bmbt_write_verify,
+};
+
+
+#if defined(DEBUG) || defined(XFS_WARN)
+STATIC int
+xfs_bmbt_keys_inorder(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_key *k1,
+ union xfs_btree_key *k2)
+{
+ return be64_to_cpu(k1->bmbt.br_startoff) <
+ be64_to_cpu(k2->bmbt.br_startoff);
+}
+
+STATIC int
+xfs_bmbt_recs_inorder(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_rec *r1,
+ union xfs_btree_rec *r2)
+{
+ return xfs_bmbt_disk_get_startoff(&r1->bmbt) +
+ xfs_bmbt_disk_get_blockcount(&r1->bmbt) <=
+ xfs_bmbt_disk_get_startoff(&r2->bmbt);
+}
+#endif /* DEBUG */
+
+static const struct xfs_btree_ops xfs_bmbt_ops = {
+ .rec_len = sizeof(xfs_bmbt_rec_t),
+ .key_len = sizeof(xfs_bmbt_key_t),
+
+ .dup_cursor = xfs_bmbt_dup_cursor,
+ .update_cursor = xfs_bmbt_update_cursor,
+ .alloc_block = xfs_bmbt_alloc_block,
+ .free_block = xfs_bmbt_free_block,
+ .get_maxrecs = xfs_bmbt_get_maxrecs,
+ .get_minrecs = xfs_bmbt_get_minrecs,
+ .get_dmaxrecs = xfs_bmbt_get_dmaxrecs,
+ .init_key_from_rec = xfs_bmbt_init_key_from_rec,
+ .init_rec_from_key = xfs_bmbt_init_rec_from_key,
+ .init_rec_from_cur = xfs_bmbt_init_rec_from_cur,
+ .init_ptr_from_cur = xfs_bmbt_init_ptr_from_cur,
+ .key_diff = xfs_bmbt_key_diff,
+ .buf_ops = &xfs_bmbt_buf_ops,
+#if defined(DEBUG) || defined(XFS_WARN)
+ .keys_inorder = xfs_bmbt_keys_inorder,
+ .recs_inorder = xfs_bmbt_recs_inorder,
+#endif
+};
+
+/*
+ * Allocate a new bmap btree cursor.
+ */
+struct xfs_btree_cur * /* new bmap btree cursor */
+xfs_bmbt_init_cursor(
+ struct xfs_mount *mp, /* file system mount point */
+ struct xfs_trans *tp, /* transaction pointer */
+ struct xfs_inode *ip, /* inode owning the btree */
+ int whichfork) /* data or attr fork */
+{
+ struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
+ struct xfs_btree_cur *cur;
+
+ cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
+
+ cur->bc_tp = tp;
+ cur->bc_mp = mp;
+ cur->bc_nlevels = be16_to_cpu(ifp->if_broot->bb_level) + 1;
+ cur->bc_btnum = XFS_BTNUM_BMAP;
+ cur->bc_blocklog = mp->m_sb.sb_blocklog;
+
+ cur->bc_ops = &xfs_bmbt_ops;
+ cur->bc_flags = XFS_BTREE_LONG_PTRS | XFS_BTREE_ROOT_IN_INODE;
+ if (xfs_sb_version_hascrc(&mp->m_sb))
+ cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
+
+ cur->bc_private.b.forksize = XFS_IFORK_SIZE(ip, whichfork);
+ cur->bc_private.b.ip = ip;
+ cur->bc_private.b.firstblock = NULLFSBLOCK;
+ cur->bc_private.b.flist = NULL;
+ cur->bc_private.b.allocated = 0;
+ cur->bc_private.b.flags = 0;
+ cur->bc_private.b.whichfork = whichfork;
+
+ return cur;
+}
+
+/*
+ * Calculate number of records in a bmap btree block.
+ */
+int
+xfs_bmbt_maxrecs(
+ struct xfs_mount *mp,
+ int blocklen,
+ int leaf)
+{
+ blocklen -= XFS_BMBT_BLOCK_LEN(mp);
+
+ if (leaf)
+ return blocklen / sizeof(xfs_bmbt_rec_t);
+ return blocklen / (sizeof(xfs_bmbt_key_t) + sizeof(xfs_bmbt_ptr_t));
+}
+
+/*
+ * Calculate number of records in a bmap btree inode root.
+ */
+int
+xfs_bmdr_maxrecs(
+ int blocklen,
+ int leaf)
+{
+ blocklen -= sizeof(xfs_bmdr_block_t);
+
+ if (leaf)
+ return blocklen / sizeof(xfs_bmdr_rec_t);
+ return blocklen / (sizeof(xfs_bmdr_key_t) + sizeof(xfs_bmdr_ptr_t));
+}
+
+/*
+ * Change the owner of a btree format fork fo the inode passed in. Change it to
+ * the owner of that is passed in so that we can change owners before or after
+ * we switch forks between inodes. The operation that the caller is doing will
+ * determine whether is needs to change owner before or after the switch.
+ *
+ * For demand paged transactional modification, the fork switch should be done
+ * after reading in all the blocks, modifying them and pinning them in the
+ * transaction. For modification when the buffers are already pinned in memory,
+ * the fork switch can be done before changing the owner as we won't need to
+ * validate the owner until the btree buffers are unpinned and writes can occur
+ * again.
+ *
+ * For recovery based ownership change, there is no transactional context and
+ * so a buffer list must be supplied so that we can record the buffers that we
+ * modified for the caller to issue IO on.
+ */
+int
+xfs_bmbt_change_owner(
+ struct xfs_trans *tp,
+ struct xfs_inode *ip,
+ int whichfork,
+ xfs_ino_t new_owner,
+ struct list_head *buffer_list)
+{
+ struct xfs_btree_cur *cur;
+ int error;
+
+ ASSERT(tp || buffer_list);
+ ASSERT(!(tp && buffer_list));
+ if (whichfork == XFS_DATA_FORK)
+ ASSERT(ip->i_d.di_format == XFS_DINODE_FMT_BTREE);
+ else
+ ASSERT(ip->i_d.di_aformat == XFS_DINODE_FMT_BTREE);
+
+ cur = xfs_bmbt_init_cursor(ip->i_mount, tp, ip, whichfork);
+ if (!cur)
+ return -ENOMEM;
+
+ error = xfs_btree_change_owner(cur, new_owner, buffer_list);
+ xfs_btree_del_cursor(cur, error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
+ return error;
+}