]> git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blobdiff - fs/xfs/libxfs/xfs_rmap.c
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[mirror_ubuntu-zesty-kernel.git] / fs / xfs / libxfs / xfs_rmap.c
index ce29d6b7cd58e3b179e3cff9e8cbcbc83fbfd835..73d05407d6636240a4c9ef29442102bbb9d9a198 100644 (file)
 #include "xfs_trans.h"
 #include "xfs_alloc.h"
 #include "xfs_rmap.h"
+#include "xfs_rmap_btree.h"
 #include "xfs_trans_space.h"
 #include "xfs_trace.h"
 #include "xfs_error.h"
 #include "xfs_extent_busy.h"
+#include "xfs_bmap.h"
+#include "xfs_inode.h"
 
 /*
  * Lookup the first record less than or equal to [bno, len, owner, offset]
@@ -91,13 +94,58 @@ xfs_rmap_update(
        struct xfs_rmap_irec    *irec)
 {
        union xfs_btree_rec     rec;
+       int                     error;
+
+       trace_xfs_rmap_update(cur->bc_mp, cur->bc_private.a.agno,
+                       irec->rm_startblock, irec->rm_blockcount,
+                       irec->rm_owner, irec->rm_offset, irec->rm_flags);
 
        rec.rmap.rm_startblock = cpu_to_be32(irec->rm_startblock);
        rec.rmap.rm_blockcount = cpu_to_be32(irec->rm_blockcount);
        rec.rmap.rm_owner = cpu_to_be64(irec->rm_owner);
        rec.rmap.rm_offset = cpu_to_be64(
                        xfs_rmap_irec_offset_pack(irec));
-       return xfs_btree_update(cur, &rec);
+       error = xfs_btree_update(cur, &rec);
+       if (error)
+               trace_xfs_rmap_update_error(cur->bc_mp,
+                               cur->bc_private.a.agno, error, _RET_IP_);
+       return error;
+}
+
+int
+xfs_rmap_insert(
+       struct xfs_btree_cur    *rcur,
+       xfs_agblock_t           agbno,
+       xfs_extlen_t            len,
+       uint64_t                owner,
+       uint64_t                offset,
+       unsigned int            flags)
+{
+       int                     i;
+       int                     error;
+
+       trace_xfs_rmap_insert(rcur->bc_mp, rcur->bc_private.a.agno, agbno,
+                       len, owner, offset, flags);
+
+       error = xfs_rmap_lookup_eq(rcur, agbno, len, owner, offset, flags, &i);
+       if (error)
+               goto done;
+       XFS_WANT_CORRUPTED_GOTO(rcur->bc_mp, i == 0, done);
+
+       rcur->bc_rec.r.rm_startblock = agbno;
+       rcur->bc_rec.r.rm_blockcount = len;
+       rcur->bc_rec.r.rm_owner = owner;
+       rcur->bc_rec.r.rm_offset = offset;
+       rcur->bc_rec.r.rm_flags = flags;
+       error = xfs_btree_insert(rcur, &i);
+       if (error)
+               goto done;
+       XFS_WANT_CORRUPTED_GOTO(rcur->bc_mp, i == 1, done);
+done:
+       if (error)
+               trace_xfs_rmap_insert_error(rcur->bc_mp,
+                               rcur->bc_private.a.agno, error, _RET_IP_);
+       return error;
 }
 
 static int
@@ -132,6 +180,212 @@ xfs_rmap_get_rec(
        return xfs_rmap_btrec_to_irec(rec, irec);
 }
 
+/*
+ * Find the extent in the rmap btree and remove it.
+ *
+ * The record we find should always be an exact match for the extent that we're
+ * looking for, since we insert them into the btree without modification.
+ *
+ * Special Case #1: when growing the filesystem, we "free" an extent when
+ * growing the last AG. This extent is new space and so it is not tracked as
+ * used space in the btree. The growfs code will pass in an owner of
+ * XFS_RMAP_OWN_NULL to indicate that it expected that there is no owner of this
+ * extent. We verify that - the extent lookup result in a record that does not
+ * overlap.
+ *
+ * Special Case #2: EFIs do not record the owner of the extent, so when
+ * recovering EFIs from the log we pass in XFS_RMAP_OWN_UNKNOWN to tell the rmap
+ * btree to ignore the owner (i.e. wildcard match) so we don't trigger
+ * corruption checks during log recovery.
+ */
+STATIC int
+xfs_rmap_unmap(
+       struct xfs_btree_cur    *cur,
+       xfs_agblock_t           bno,
+       xfs_extlen_t            len,
+       bool                    unwritten,
+       struct xfs_owner_info   *oinfo)
+{
+       struct xfs_mount        *mp = cur->bc_mp;
+       struct xfs_rmap_irec    ltrec;
+       uint64_t                ltoff;
+       int                     error = 0;
+       int                     i;
+       uint64_t                owner;
+       uint64_t                offset;
+       unsigned int            flags;
+       bool                    ignore_off;
+
+       xfs_owner_info_unpack(oinfo, &owner, &offset, &flags);
+       ignore_off = XFS_RMAP_NON_INODE_OWNER(owner) ||
+                       (flags & XFS_RMAP_BMBT_BLOCK);
+       if (unwritten)
+               flags |= XFS_RMAP_UNWRITTEN;
+       trace_xfs_rmap_unmap(mp, cur->bc_private.a.agno, bno, len,
+                       unwritten, oinfo);
+
+       /*
+        * We should always have a left record because there's a static record
+        * for the AG headers at rm_startblock == 0 created by mkfs/growfs that
+        * will not ever be removed from the tree.
+        */
+       error = xfs_rmap_lookup_le(cur, bno, len, owner, offset, flags, &i);
+       if (error)
+               goto out_error;
+       XFS_WANT_CORRUPTED_GOTO(mp, i == 1, out_error);
+
+       error = xfs_rmap_get_rec(cur, &ltrec, &i);
+       if (error)
+               goto out_error;
+       XFS_WANT_CORRUPTED_GOTO(mp, i == 1, out_error);
+       trace_xfs_rmap_lookup_le_range_result(cur->bc_mp,
+                       cur->bc_private.a.agno, ltrec.rm_startblock,
+                       ltrec.rm_blockcount, ltrec.rm_owner,
+                       ltrec.rm_offset, ltrec.rm_flags);
+       ltoff = ltrec.rm_offset;
+
+       /*
+        * For growfs, the incoming extent must be beyond the left record we
+        * just found as it is new space and won't be used by anyone. This is
+        * just a corruption check as we don't actually do anything with this
+        * extent.  Note that we need to use >= instead of > because it might
+        * be the case that the "left" extent goes all the way to EOFS.
+        */
+       if (owner == XFS_RMAP_OWN_NULL) {
+               XFS_WANT_CORRUPTED_GOTO(mp, bno >= ltrec.rm_startblock +
+                                               ltrec.rm_blockcount, out_error);
+               goto out_done;
+       }
+
+       /* Make sure the unwritten flag matches. */
+       XFS_WANT_CORRUPTED_GOTO(mp, (flags & XFS_RMAP_UNWRITTEN) ==
+                       (ltrec.rm_flags & XFS_RMAP_UNWRITTEN), out_error);
+
+       /* Make sure the extent we found covers the entire freeing range. */
+       XFS_WANT_CORRUPTED_GOTO(mp, ltrec.rm_startblock <= bno &&
+               ltrec.rm_startblock + ltrec.rm_blockcount >=
+               bno + len, out_error);
+
+       /* Make sure the owner matches what we expect to find in the tree. */
+       XFS_WANT_CORRUPTED_GOTO(mp, owner == ltrec.rm_owner ||
+                                   XFS_RMAP_NON_INODE_OWNER(owner), out_error);
+
+       /* Check the offset, if necessary. */
+       if (!XFS_RMAP_NON_INODE_OWNER(owner)) {
+               if (flags & XFS_RMAP_BMBT_BLOCK) {
+                       XFS_WANT_CORRUPTED_GOTO(mp,
+                                       ltrec.rm_flags & XFS_RMAP_BMBT_BLOCK,
+                                       out_error);
+               } else {
+                       XFS_WANT_CORRUPTED_GOTO(mp,
+                                       ltrec.rm_offset <= offset, out_error);
+                       XFS_WANT_CORRUPTED_GOTO(mp,
+                                       ltoff + ltrec.rm_blockcount >= offset + len,
+                                       out_error);
+               }
+       }
+
+       if (ltrec.rm_startblock == bno && ltrec.rm_blockcount == len) {
+               /* exact match, simply remove the record from rmap tree */
+               trace_xfs_rmap_delete(mp, cur->bc_private.a.agno,
+                               ltrec.rm_startblock, ltrec.rm_blockcount,
+                               ltrec.rm_owner, ltrec.rm_offset,
+                               ltrec.rm_flags);
+               error = xfs_btree_delete(cur, &i);
+               if (error)
+                       goto out_error;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, out_error);
+       } else if (ltrec.rm_startblock == bno) {
+               /*
+                * overlap left hand side of extent: move the start, trim the
+                * length and update the current record.
+                *
+                *       ltbno                ltlen
+                * Orig:    |oooooooooooooooooooo|
+                * Freeing: |fffffffff|
+                * Result:            |rrrrrrrrrr|
+                *         bno       len
+                */
+               ltrec.rm_startblock += len;
+               ltrec.rm_blockcount -= len;
+               if (!ignore_off)
+                       ltrec.rm_offset += len;
+               error = xfs_rmap_update(cur, &ltrec);
+               if (error)
+                       goto out_error;
+       } else if (ltrec.rm_startblock + ltrec.rm_blockcount == bno + len) {
+               /*
+                * overlap right hand side of extent: trim the length and update
+                * the current record.
+                *
+                *       ltbno                ltlen
+                * Orig:    |oooooooooooooooooooo|
+                * Freeing:            |fffffffff|
+                * Result:  |rrrrrrrrrr|
+                *                    bno       len
+                */
+               ltrec.rm_blockcount -= len;
+               error = xfs_rmap_update(cur, &ltrec);
+               if (error)
+                       goto out_error;
+       } else {
+
+               /*
+                * overlap middle of extent: trim the length of the existing
+                * record to the length of the new left-extent size, increment
+                * the insertion position so we can insert a new record
+                * containing the remaining right-extent space.
+                *
+                *       ltbno                ltlen
+                * Orig:    |oooooooooooooooooooo|
+                * Freeing:       |fffffffff|
+                * Result:  |rrrrr|         |rrrr|
+                *               bno       len
+                */
+               xfs_extlen_t    orig_len = ltrec.rm_blockcount;
+
+               ltrec.rm_blockcount = bno - ltrec.rm_startblock;
+               error = xfs_rmap_update(cur, &ltrec);
+               if (error)
+                       goto out_error;
+
+               error = xfs_btree_increment(cur, 0, &i);
+               if (error)
+                       goto out_error;
+
+               cur->bc_rec.r.rm_startblock = bno + len;
+               cur->bc_rec.r.rm_blockcount = orig_len - len -
+                                                    ltrec.rm_blockcount;
+               cur->bc_rec.r.rm_owner = ltrec.rm_owner;
+               if (ignore_off)
+                       cur->bc_rec.r.rm_offset = 0;
+               else
+                       cur->bc_rec.r.rm_offset = offset + len;
+               cur->bc_rec.r.rm_flags = flags;
+               trace_xfs_rmap_insert(mp, cur->bc_private.a.agno,
+                               cur->bc_rec.r.rm_startblock,
+                               cur->bc_rec.r.rm_blockcount,
+                               cur->bc_rec.r.rm_owner,
+                               cur->bc_rec.r.rm_offset,
+                               cur->bc_rec.r.rm_flags);
+               error = xfs_btree_insert(cur, &i);
+               if (error)
+                       goto out_error;
+       }
+
+out_done:
+       trace_xfs_rmap_unmap_done(mp, cur->bc_private.a.agno, bno, len,
+                       unwritten, oinfo);
+out_error:
+       if (error)
+               trace_xfs_rmap_unmap_error(mp, cur->bc_private.a.agno,
+                               error, _RET_IP_);
+       return error;
+}
+
+/*
+ * Remove a reference to an extent in the rmap btree.
+ */
 int
 xfs_rmap_free(
        struct xfs_trans        *tp,
@@ -142,22 +396,238 @@ xfs_rmap_free(
        struct xfs_owner_info   *oinfo)
 {
        struct xfs_mount        *mp = tp->t_mountp;
-       int                     error = 0;
+       struct xfs_btree_cur    *cur;
+       int                     error;
 
        if (!xfs_sb_version_hasrmapbt(&mp->m_sb))
                return 0;
 
-       trace_xfs_rmap_unmap(mp, agno, bno, len, false, oinfo);
-       if (1)
+       cur = xfs_rmapbt_init_cursor(mp, tp, agbp, agno);
+
+       error = xfs_rmap_unmap(cur, bno, len, false, oinfo);
+       if (error)
                goto out_error;
-       trace_xfs_rmap_unmap_done(mp, agno, bno, len, false, oinfo);
+
+       xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
        return 0;
 
 out_error:
-       trace_xfs_rmap_unmap_error(mp, agno, error, _RET_IP_);
+       xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
        return error;
 }
 
+/*
+ * A mergeable rmap must have the same owner and the same values for
+ * the unwritten, attr_fork, and bmbt flags.  The startblock and
+ * offset are checked separately.
+ */
+static bool
+xfs_rmap_is_mergeable(
+       struct xfs_rmap_irec    *irec,
+       uint64_t                owner,
+       unsigned int            flags)
+{
+       if (irec->rm_owner == XFS_RMAP_OWN_NULL)
+               return false;
+       if (irec->rm_owner != owner)
+               return false;
+       if ((flags & XFS_RMAP_UNWRITTEN) ^
+           (irec->rm_flags & XFS_RMAP_UNWRITTEN))
+               return false;
+       if ((flags & XFS_RMAP_ATTR_FORK) ^
+           (irec->rm_flags & XFS_RMAP_ATTR_FORK))
+               return false;
+       if ((flags & XFS_RMAP_BMBT_BLOCK) ^
+           (irec->rm_flags & XFS_RMAP_BMBT_BLOCK))
+               return false;
+       return true;
+}
+
+/*
+ * When we allocate a new block, the first thing we do is add a reference to
+ * the extent in the rmap btree. This takes the form of a [agbno, length,
+ * owner, offset] record.  Flags are encoded in the high bits of the offset
+ * field.
+ */
+STATIC int
+xfs_rmap_map(
+       struct xfs_btree_cur    *cur,
+       xfs_agblock_t           bno,
+       xfs_extlen_t            len,
+       bool                    unwritten,
+       struct xfs_owner_info   *oinfo)
+{
+       struct xfs_mount        *mp = cur->bc_mp;
+       struct xfs_rmap_irec    ltrec;
+       struct xfs_rmap_irec    gtrec;
+       int                     have_gt;
+       int                     have_lt;
+       int                     error = 0;
+       int                     i;
+       uint64_t                owner;
+       uint64_t                offset;
+       unsigned int            flags = 0;
+       bool                    ignore_off;
+
+       xfs_owner_info_unpack(oinfo, &owner, &offset, &flags);
+       ASSERT(owner != 0);
+       ignore_off = XFS_RMAP_NON_INODE_OWNER(owner) ||
+                       (flags & XFS_RMAP_BMBT_BLOCK);
+       if (unwritten)
+               flags |= XFS_RMAP_UNWRITTEN;
+       trace_xfs_rmap_map(mp, cur->bc_private.a.agno, bno, len,
+                       unwritten, oinfo);
+
+       /*
+        * For the initial lookup, look for an exact match or the left-adjacent
+        * record for our insertion point. This will also give us the record for
+        * start block contiguity tests.
+        */
+       error = xfs_rmap_lookup_le(cur, bno, len, owner, offset, flags,
+                       &have_lt);
+       if (error)
+               goto out_error;
+       XFS_WANT_CORRUPTED_GOTO(mp, have_lt == 1, out_error);
+
+       error = xfs_rmap_get_rec(cur, &ltrec, &have_lt);
+       if (error)
+               goto out_error;
+       XFS_WANT_CORRUPTED_GOTO(mp, have_lt == 1, out_error);
+       trace_xfs_rmap_lookup_le_range_result(cur->bc_mp,
+                       cur->bc_private.a.agno, ltrec.rm_startblock,
+                       ltrec.rm_blockcount, ltrec.rm_owner,
+                       ltrec.rm_offset, ltrec.rm_flags);
+
+       if (!xfs_rmap_is_mergeable(&ltrec, owner, flags))
+               have_lt = 0;
+
+       XFS_WANT_CORRUPTED_GOTO(mp,
+               have_lt == 0 ||
+               ltrec.rm_startblock + ltrec.rm_blockcount <= bno, out_error);
+
+       /*
+        * Increment the cursor to see if we have a right-adjacent record to our
+        * insertion point. This will give us the record for end block
+        * contiguity tests.
+        */
+       error = xfs_btree_increment(cur, 0, &have_gt);
+       if (error)
+               goto out_error;
+       if (have_gt) {
+               error = xfs_rmap_get_rec(cur, &gtrec, &have_gt);
+               if (error)
+                       goto out_error;
+               XFS_WANT_CORRUPTED_GOTO(mp, have_gt == 1, out_error);
+               XFS_WANT_CORRUPTED_GOTO(mp, bno + len <= gtrec.rm_startblock,
+                                       out_error);
+               trace_xfs_rmap_find_right_neighbor_result(cur->bc_mp,
+                       cur->bc_private.a.agno, gtrec.rm_startblock,
+                       gtrec.rm_blockcount, gtrec.rm_owner,
+                       gtrec.rm_offset, gtrec.rm_flags);
+               if (!xfs_rmap_is_mergeable(&gtrec, owner, flags))
+                       have_gt = 0;
+       }
+
+       /*
+        * Note: cursor currently points one record to the right of ltrec, even
+        * if there is no record in the tree to the right.
+        */
+       if (have_lt &&
+           ltrec.rm_startblock + ltrec.rm_blockcount == bno &&
+           (ignore_off || ltrec.rm_offset + ltrec.rm_blockcount == offset)) {
+               /*
+                * left edge contiguous, merge into left record.
+                *
+                *       ltbno     ltlen
+                * orig:   |ooooooooo|
+                * adding:           |aaaaaaaaa|
+                * result: |rrrrrrrrrrrrrrrrrrr|
+                *                  bno       len
+                */
+               ltrec.rm_blockcount += len;
+               if (have_gt &&
+                   bno + len == gtrec.rm_startblock &&
+                   (ignore_off || offset + len == gtrec.rm_offset) &&
+                   (unsigned long)ltrec.rm_blockcount + len +
+                               gtrec.rm_blockcount <= XFS_RMAP_LEN_MAX) {
+                       /*
+                        * right edge also contiguous, delete right record
+                        * and merge into left record.
+                        *
+                        *       ltbno     ltlen    gtbno     gtlen
+                        * orig:   |ooooooooo|         |ooooooooo|
+                        * adding:           |aaaaaaaaa|
+                        * result: |rrrrrrrrrrrrrrrrrrrrrrrrrrrrr|
+                        */
+                       ltrec.rm_blockcount += gtrec.rm_blockcount;
+                       trace_xfs_rmap_delete(mp, cur->bc_private.a.agno,
+                                       gtrec.rm_startblock,
+                                       gtrec.rm_blockcount,
+                                       gtrec.rm_owner,
+                                       gtrec.rm_offset,
+                                       gtrec.rm_flags);
+                       error = xfs_btree_delete(cur, &i);
+                       if (error)
+                               goto out_error;
+                       XFS_WANT_CORRUPTED_GOTO(mp, i == 1, out_error);
+               }
+
+               /* point the cursor back to the left record and update */
+               error = xfs_btree_decrement(cur, 0, &have_gt);
+               if (error)
+                       goto out_error;
+               error = xfs_rmap_update(cur, &ltrec);
+               if (error)
+                       goto out_error;
+       } else if (have_gt &&
+                  bno + len == gtrec.rm_startblock &&
+                  (ignore_off || offset + len == gtrec.rm_offset)) {
+               /*
+                * right edge contiguous, merge into right record.
+                *
+                *                 gtbno     gtlen
+                * Orig:             |ooooooooo|
+                * adding: |aaaaaaaaa|
+                * Result: |rrrrrrrrrrrrrrrrrrr|
+                *        bno       len
+                */
+               gtrec.rm_startblock = bno;
+               gtrec.rm_blockcount += len;
+               if (!ignore_off)
+                       gtrec.rm_offset = offset;
+               error = xfs_rmap_update(cur, &gtrec);
+               if (error)
+                       goto out_error;
+       } else {
+               /*
+                * no contiguous edge with identical owner, insert
+                * new record at current cursor position.
+                */
+               cur->bc_rec.r.rm_startblock = bno;
+               cur->bc_rec.r.rm_blockcount = len;
+               cur->bc_rec.r.rm_owner = owner;
+               cur->bc_rec.r.rm_offset = offset;
+               cur->bc_rec.r.rm_flags = flags;
+               trace_xfs_rmap_insert(mp, cur->bc_private.a.agno, bno, len,
+                       owner, offset, flags);
+               error = xfs_btree_insert(cur, &i);
+               if (error)
+                       goto out_error;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, out_error);
+       }
+
+       trace_xfs_rmap_map_done(mp, cur->bc_private.a.agno, bno, len,
+                       unwritten, oinfo);
+out_error:
+       if (error)
+               trace_xfs_rmap_map_error(mp, cur->bc_private.a.agno,
+                               error, _RET_IP_);
+       return error;
+}
+
+/*
+ * Add a reference to an extent in the rmap btree.
+ */
 int
 xfs_rmap_alloc(
        struct xfs_trans        *tp,
@@ -168,18 +638,762 @@ xfs_rmap_alloc(
        struct xfs_owner_info   *oinfo)
 {
        struct xfs_mount        *mp = tp->t_mountp;
-       int                     error = 0;
+       struct xfs_btree_cur    *cur;
+       int                     error;
 
        if (!xfs_sb_version_hasrmapbt(&mp->m_sb))
                return 0;
 
-       trace_xfs_rmap_map(mp, agno, bno, len, false, oinfo);
-       if (1)
+       cur = xfs_rmapbt_init_cursor(mp, tp, agbp, agno);
+       error = xfs_rmap_map(cur, bno, len, false, oinfo);
+       if (error)
                goto out_error;
-       trace_xfs_rmap_map_done(mp, agno, bno, len, false, oinfo);
+
+       xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
        return 0;
 
 out_error:
-       trace_xfs_rmap_map_error(mp, agno, error, _RET_IP_);
+       xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
        return error;
 }
+
+#define RMAP_LEFT_CONTIG       (1 << 0)
+#define RMAP_RIGHT_CONTIG      (1 << 1)
+#define RMAP_LEFT_FILLING      (1 << 2)
+#define RMAP_RIGHT_FILLING     (1 << 3)
+#define RMAP_LEFT_VALID                (1 << 6)
+#define RMAP_RIGHT_VALID       (1 << 7)
+
+#define LEFT           r[0]
+#define RIGHT          r[1]
+#define PREV           r[2]
+#define NEW            r[3]
+
+/*
+ * Convert an unwritten extent to a real extent or vice versa.
+ * Does not handle overlapping extents.
+ */
+STATIC int
+xfs_rmap_convert(
+       struct xfs_btree_cur    *cur,
+       xfs_agblock_t           bno,
+       xfs_extlen_t            len,
+       bool                    unwritten,
+       struct xfs_owner_info   *oinfo)
+{
+       struct xfs_mount        *mp = cur->bc_mp;
+       struct xfs_rmap_irec    r[4];   /* neighbor extent entries */
+                                       /* left is 0, right is 1, prev is 2 */
+                                       /* new is 3 */
+       uint64_t                owner;
+       uint64_t                offset;
+       uint64_t                new_endoff;
+       unsigned int            oldext;
+       unsigned int            newext;
+       unsigned int            flags = 0;
+       int                     i;
+       int                     state = 0;
+       int                     error;
+
+       xfs_owner_info_unpack(oinfo, &owner, &offset, &flags);
+       ASSERT(!(XFS_RMAP_NON_INODE_OWNER(owner) ||
+                       (flags & (XFS_RMAP_ATTR_FORK | XFS_RMAP_BMBT_BLOCK))));
+       oldext = unwritten ? XFS_RMAP_UNWRITTEN : 0;
+       new_endoff = offset + len;
+       trace_xfs_rmap_convert(mp, cur->bc_private.a.agno, bno, len,
+                       unwritten, oinfo);
+
+       /*
+        * For the initial lookup, look for an exact match or the left-adjacent
+        * record for our insertion point. This will also give us the record for
+        * start block contiguity tests.
+        */
+       error = xfs_rmap_lookup_le(cur, bno, len, owner, offset, oldext, &i);
+       if (error)
+               goto done;
+       XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+
+       error = xfs_rmap_get_rec(cur, &PREV, &i);
+       if (error)
+               goto done;
+       XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+       trace_xfs_rmap_lookup_le_range_result(cur->bc_mp,
+                       cur->bc_private.a.agno, PREV.rm_startblock,
+                       PREV.rm_blockcount, PREV.rm_owner,
+                       PREV.rm_offset, PREV.rm_flags);
+
+       ASSERT(PREV.rm_offset <= offset);
+       ASSERT(PREV.rm_offset + PREV.rm_blockcount >= new_endoff);
+       ASSERT((PREV.rm_flags & XFS_RMAP_UNWRITTEN) == oldext);
+       newext = ~oldext & XFS_RMAP_UNWRITTEN;
+
+       /*
+        * Set flags determining what part of the previous oldext allocation
+        * extent is being replaced by a newext allocation.
+        */
+       if (PREV.rm_offset == offset)
+               state |= RMAP_LEFT_FILLING;
+       if (PREV.rm_offset + PREV.rm_blockcount == new_endoff)
+               state |= RMAP_RIGHT_FILLING;
+
+       /*
+        * Decrement the cursor to see if we have a left-adjacent record to our
+        * insertion point. This will give us the record for end block
+        * contiguity tests.
+        */
+       error = xfs_btree_decrement(cur, 0, &i);
+       if (error)
+               goto done;
+       if (i) {
+               state |= RMAP_LEFT_VALID;
+               error = xfs_rmap_get_rec(cur, &LEFT, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               XFS_WANT_CORRUPTED_GOTO(mp,
+                               LEFT.rm_startblock + LEFT.rm_blockcount <= bno,
+                               done);
+               trace_xfs_rmap_find_left_neighbor_result(cur->bc_mp,
+                               cur->bc_private.a.agno, LEFT.rm_startblock,
+                               LEFT.rm_blockcount, LEFT.rm_owner,
+                               LEFT.rm_offset, LEFT.rm_flags);
+               if (LEFT.rm_startblock + LEFT.rm_blockcount == bno &&
+                   LEFT.rm_offset + LEFT.rm_blockcount == offset &&
+                   xfs_rmap_is_mergeable(&LEFT, owner, newext))
+                       state |= RMAP_LEFT_CONTIG;
+       }
+
+       /*
+        * Increment the cursor to see if we have a right-adjacent record to our
+        * insertion point. This will give us the record for end block
+        * contiguity tests.
+        */
+       error = xfs_btree_increment(cur, 0, &i);
+       if (error)
+               goto done;
+       XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+       error = xfs_btree_increment(cur, 0, &i);
+       if (error)
+               goto done;
+       if (i) {
+               state |= RMAP_RIGHT_VALID;
+               error = xfs_rmap_get_rec(cur, &RIGHT, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               XFS_WANT_CORRUPTED_GOTO(mp, bno + len <= RIGHT.rm_startblock,
+                                       done);
+               trace_xfs_rmap_find_right_neighbor_result(cur->bc_mp,
+                               cur->bc_private.a.agno, RIGHT.rm_startblock,
+                               RIGHT.rm_blockcount, RIGHT.rm_owner,
+                               RIGHT.rm_offset, RIGHT.rm_flags);
+               if (bno + len == RIGHT.rm_startblock &&
+                   offset + len == RIGHT.rm_offset &&
+                   xfs_rmap_is_mergeable(&RIGHT, owner, newext))
+                       state |= RMAP_RIGHT_CONTIG;
+       }
+
+       /* check that left + prev + right is not too long */
+       if ((state & (RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG |
+                        RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG)) ==
+           (RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG |
+            RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG) &&
+           (unsigned long)LEFT.rm_blockcount + len +
+            RIGHT.rm_blockcount > XFS_RMAP_LEN_MAX)
+               state &= ~RMAP_RIGHT_CONTIG;
+
+       trace_xfs_rmap_convert_state(mp, cur->bc_private.a.agno, state,
+                       _RET_IP_);
+
+       /* reset the cursor back to PREV */
+       error = xfs_rmap_lookup_le(cur, bno, len, owner, offset, oldext, &i);
+       if (error)
+               goto done;
+       XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+
+       /*
+        * Switch out based on the FILLING and CONTIG state bits.
+        */
+       switch (state & (RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG |
+                        RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG)) {
+       case RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG |
+            RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG:
+               /*
+                * Setting all of a previous oldext extent to newext.
+                * The left and right neighbors are both contiguous with new.
+                */
+               error = xfs_btree_increment(cur, 0, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               trace_xfs_rmap_delete(mp, cur->bc_private.a.agno,
+                               RIGHT.rm_startblock, RIGHT.rm_blockcount,
+                               RIGHT.rm_owner, RIGHT.rm_offset,
+                               RIGHT.rm_flags);
+               error = xfs_btree_delete(cur, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               error = xfs_btree_decrement(cur, 0, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               trace_xfs_rmap_delete(mp, cur->bc_private.a.agno,
+                               PREV.rm_startblock, PREV.rm_blockcount,
+                               PREV.rm_owner, PREV.rm_offset,
+                               PREV.rm_flags);
+               error = xfs_btree_delete(cur, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               error = xfs_btree_decrement(cur, 0, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               NEW = LEFT;
+               NEW.rm_blockcount += PREV.rm_blockcount + RIGHT.rm_blockcount;
+               error = xfs_rmap_update(cur, &NEW);
+               if (error)
+                       goto done;
+               break;
+
+       case RMAP_LEFT_FILLING | RMAP_RIGHT_FILLING | RMAP_LEFT_CONTIG:
+               /*
+                * Setting all of a previous oldext extent to newext.
+                * The left neighbor is contiguous, the right is not.
+                */
+               trace_xfs_rmap_delete(mp, cur->bc_private.a.agno,
+                               PREV.rm_startblock, PREV.rm_blockcount,
+                               PREV.rm_owner, PREV.rm_offset,
+                               PREV.rm_flags);
+               error = xfs_btree_delete(cur, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               error = xfs_btree_decrement(cur, 0, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               NEW = LEFT;
+               NEW.rm_blockcount += PREV.rm_blockcount;
+               error = xfs_rmap_update(cur, &NEW);
+               if (error)
+                       goto done;
+               break;
+
+       case RMAP_LEFT_FILLING | RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG:
+               /*
+                * Setting all of a previous oldext extent to newext.
+                * The right neighbor is contiguous, the left is not.
+                */
+               error = xfs_btree_increment(cur, 0, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               trace_xfs_rmap_delete(mp, cur->bc_private.a.agno,
+                               RIGHT.rm_startblock, RIGHT.rm_blockcount,
+                               RIGHT.rm_owner, RIGHT.rm_offset,
+                               RIGHT.rm_flags);
+               error = xfs_btree_delete(cur, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               error = xfs_btree_decrement(cur, 0, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               NEW = PREV;
+               NEW.rm_blockcount = len + RIGHT.rm_blockcount;
+               NEW.rm_flags = newext;
+               error = xfs_rmap_update(cur, &NEW);
+               if (error)
+                       goto done;
+               break;
+
+       case RMAP_LEFT_FILLING | RMAP_RIGHT_FILLING:
+               /*
+                * Setting all of a previous oldext extent to newext.
+                * Neither the left nor right neighbors are contiguous with
+                * the new one.
+                */
+               NEW = PREV;
+               NEW.rm_flags = newext;
+               error = xfs_rmap_update(cur, &NEW);
+               if (error)
+                       goto done;
+               break;
+
+       case RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG:
+               /*
+                * Setting the first part of a previous oldext extent to newext.
+                * The left neighbor is contiguous.
+                */
+               NEW = PREV;
+               NEW.rm_offset += len;
+               NEW.rm_startblock += len;
+               NEW.rm_blockcount -= len;
+               error = xfs_rmap_update(cur, &NEW);
+               if (error)
+                       goto done;
+               error = xfs_btree_decrement(cur, 0, &i);
+               if (error)
+                       goto done;
+               NEW = LEFT;
+               NEW.rm_blockcount += len;
+               error = xfs_rmap_update(cur, &NEW);
+               if (error)
+                       goto done;
+               break;
+
+       case RMAP_LEFT_FILLING:
+               /*
+                * Setting the first part of a previous oldext extent to newext.
+                * The left neighbor is not contiguous.
+                */
+               NEW = PREV;
+               NEW.rm_startblock += len;
+               NEW.rm_offset += len;
+               NEW.rm_blockcount -= len;
+               error = xfs_rmap_update(cur, &NEW);
+               if (error)
+                       goto done;
+               NEW.rm_startblock = bno;
+               NEW.rm_owner = owner;
+               NEW.rm_offset = offset;
+               NEW.rm_blockcount = len;
+               NEW.rm_flags = newext;
+               cur->bc_rec.r = NEW;
+               trace_xfs_rmap_insert(mp, cur->bc_private.a.agno, bno,
+                               len, owner, offset, newext);
+               error = xfs_btree_insert(cur, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               break;
+
+       case RMAP_RIGHT_FILLING | RMAP_RIGHT_CONTIG:
+               /*
+                * Setting the last part of a previous oldext extent to newext.
+                * The right neighbor is contiguous with the new allocation.
+                */
+               NEW = PREV;
+               NEW.rm_blockcount -= len;
+               error = xfs_rmap_update(cur, &NEW);
+               if (error)
+                       goto done;
+               error = xfs_btree_increment(cur, 0, &i);
+               if (error)
+                       goto done;
+               NEW = RIGHT;
+               NEW.rm_offset = offset;
+               NEW.rm_startblock = bno;
+               NEW.rm_blockcount += len;
+               error = xfs_rmap_update(cur, &NEW);
+               if (error)
+                       goto done;
+               break;
+
+       case RMAP_RIGHT_FILLING:
+               /*
+                * Setting the last part of a previous oldext extent to newext.
+                * The right neighbor is not contiguous.
+                */
+               NEW = PREV;
+               NEW.rm_blockcount -= len;
+               error = xfs_rmap_update(cur, &NEW);
+               if (error)
+                       goto done;
+               error = xfs_rmap_lookup_eq(cur, bno, len, owner, offset,
+                               oldext, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
+               NEW.rm_startblock = bno;
+               NEW.rm_owner = owner;
+               NEW.rm_offset = offset;
+               NEW.rm_blockcount = len;
+               NEW.rm_flags = newext;
+               cur->bc_rec.r = NEW;
+               trace_xfs_rmap_insert(mp, cur->bc_private.a.agno, bno,
+                               len, owner, offset, newext);
+               error = xfs_btree_insert(cur, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               break;
+
+       case 0:
+               /*
+                * Setting the middle part of a previous oldext extent to
+                * newext.  Contiguity is impossible here.
+                * One extent becomes three extents.
+                */
+               /* new right extent - oldext */
+               NEW.rm_startblock = bno + len;
+               NEW.rm_owner = owner;
+               NEW.rm_offset = new_endoff;
+               NEW.rm_blockcount = PREV.rm_offset + PREV.rm_blockcount -
+                               new_endoff;
+               NEW.rm_flags = PREV.rm_flags;
+               error = xfs_rmap_update(cur, &NEW);
+               if (error)
+                       goto done;
+               /* new left extent - oldext */
+               NEW = PREV;
+               NEW.rm_blockcount = offset - PREV.rm_offset;
+               cur->bc_rec.r = NEW;
+               trace_xfs_rmap_insert(mp, cur->bc_private.a.agno,
+                               NEW.rm_startblock, NEW.rm_blockcount,
+                               NEW.rm_owner, NEW.rm_offset,
+                               NEW.rm_flags);
+               error = xfs_btree_insert(cur, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               /*
+                * Reset the cursor to the position of the new extent
+                * we are about to insert as we can't trust it after
+                * the previous insert.
+                */
+               error = xfs_rmap_lookup_eq(cur, bno, len, owner, offset,
+                               oldext, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
+               /* new middle extent - newext */
+               cur->bc_rec.r.rm_flags &= ~XFS_RMAP_UNWRITTEN;
+               cur->bc_rec.r.rm_flags |= newext;
+               trace_xfs_rmap_insert(mp, cur->bc_private.a.agno, bno, len,
+                               owner, offset, newext);
+               error = xfs_btree_insert(cur, &i);
+               if (error)
+                       goto done;
+               XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
+               break;
+
+       case RMAP_LEFT_FILLING | RMAP_LEFT_CONTIG | RMAP_RIGHT_CONTIG:
+       case RMAP_RIGHT_FILLING | RMAP_LEFT_CONTIG | RMAP_RIGHT_CONTIG:
+       case RMAP_LEFT_FILLING | RMAP_RIGHT_CONTIG:
+       case RMAP_RIGHT_FILLING | RMAP_LEFT_CONTIG:
+       case RMAP_LEFT_CONTIG | RMAP_RIGHT_CONTIG:
+       case RMAP_LEFT_CONTIG:
+       case RMAP_RIGHT_CONTIG:
+               /*
+                * These cases are all impossible.
+                */
+               ASSERT(0);
+       }
+
+       trace_xfs_rmap_convert_done(mp, cur->bc_private.a.agno, bno, len,
+                       unwritten, oinfo);
+done:
+       if (error)
+               trace_xfs_rmap_convert_error(cur->bc_mp,
+                               cur->bc_private.a.agno, error, _RET_IP_);
+       return error;
+}
+
+#undef NEW
+#undef LEFT
+#undef RIGHT
+#undef PREV
+
+struct xfs_rmap_query_range_info {
+       xfs_rmap_query_range_fn fn;
+       void                            *priv;
+};
+
+/* Format btree record and pass to our callback. */
+STATIC int
+xfs_rmap_query_range_helper(
+       struct xfs_btree_cur    *cur,
+       union xfs_btree_rec     *rec,
+       void                    *priv)
+{
+       struct xfs_rmap_query_range_info        *query = priv;
+       struct xfs_rmap_irec                    irec;
+       int                                     error;
+
+       error = xfs_rmap_btrec_to_irec(rec, &irec);
+       if (error)
+               return error;
+       return query->fn(cur, &irec, query->priv);
+}
+
+/* Find all rmaps between two keys. */
+int
+xfs_rmap_query_range(
+       struct xfs_btree_cur            *cur,
+       struct xfs_rmap_irec            *low_rec,
+       struct xfs_rmap_irec            *high_rec,
+       xfs_rmap_query_range_fn fn,
+       void                            *priv)
+{
+       union xfs_btree_irec            low_brec;
+       union xfs_btree_irec            high_brec;
+       struct xfs_rmap_query_range_info        query;
+
+       low_brec.r = *low_rec;
+       high_brec.r = *high_rec;
+       query.priv = priv;
+       query.fn = fn;
+       return xfs_btree_query_range(cur, &low_brec, &high_brec,
+                       xfs_rmap_query_range_helper, &query);
+}
+
+/* Clean up after calling xfs_rmap_finish_one. */
+void
+xfs_rmap_finish_one_cleanup(
+       struct xfs_trans        *tp,
+       struct xfs_btree_cur    *rcur,
+       int                     error)
+{
+       struct xfs_buf          *agbp;
+
+       if (rcur == NULL)
+               return;
+       agbp = rcur->bc_private.a.agbp;
+       xfs_btree_del_cursor(rcur, error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
+       if (error)
+               xfs_trans_brelse(tp, agbp);
+}
+
+/*
+ * Process one of the deferred rmap operations.  We pass back the
+ * btree cursor to maintain our lock on the rmapbt between calls.
+ * This saves time and eliminates a buffer deadlock between the
+ * superblock and the AGF because we'll always grab them in the same
+ * order.
+ */
+int
+xfs_rmap_finish_one(
+       struct xfs_trans                *tp,
+       enum xfs_rmap_intent_type       type,
+       __uint64_t                      owner,
+       int                             whichfork,
+       xfs_fileoff_t                   startoff,
+       xfs_fsblock_t                   startblock,
+       xfs_filblks_t                   blockcount,
+       xfs_exntst_t                    state,
+       struct xfs_btree_cur            **pcur)
+{
+       struct xfs_mount                *mp = tp->t_mountp;
+       struct xfs_btree_cur            *rcur;
+       struct xfs_buf                  *agbp = NULL;
+       int                             error = 0;
+       xfs_agnumber_t                  agno;
+       struct xfs_owner_info           oinfo;
+       xfs_agblock_t                   bno;
+       bool                            unwritten;
+
+       agno = XFS_FSB_TO_AGNO(mp, startblock);
+       ASSERT(agno != NULLAGNUMBER);
+       bno = XFS_FSB_TO_AGBNO(mp, startblock);
+
+       trace_xfs_rmap_deferred(mp, agno, type, bno, owner, whichfork,
+                       startoff, blockcount, state);
+
+       if (XFS_TEST_ERROR(false, mp,
+                       XFS_ERRTAG_RMAP_FINISH_ONE,
+                       XFS_RANDOM_RMAP_FINISH_ONE))
+               return -EIO;
+
+       /*
+        * If we haven't gotten a cursor or the cursor AG doesn't match
+        * the startblock, get one now.
+        */
+       rcur = *pcur;
+       if (rcur != NULL && rcur->bc_private.a.agno != agno) {
+               xfs_rmap_finish_one_cleanup(tp, rcur, 0);
+               rcur = NULL;
+               *pcur = NULL;
+       }
+       if (rcur == NULL) {
+               /*
+                * Refresh the freelist before we start changing the
+                * rmapbt, because a shape change could cause us to
+                * allocate blocks.
+                */
+               error = xfs_free_extent_fix_freelist(tp, agno, &agbp);
+               if (error)
+                       return error;
+               if (!agbp)
+                       return -EFSCORRUPTED;
+
+               rcur = xfs_rmapbt_init_cursor(mp, tp, agbp, agno);
+               if (!rcur) {
+                       error = -ENOMEM;
+                       goto out_cur;
+               }
+       }
+       *pcur = rcur;
+
+       xfs_rmap_ino_owner(&oinfo, owner, whichfork, startoff);
+       unwritten = state == XFS_EXT_UNWRITTEN;
+       bno = XFS_FSB_TO_AGBNO(rcur->bc_mp, startblock);
+
+       switch (type) {
+       case XFS_RMAP_ALLOC:
+       case XFS_RMAP_MAP:
+               error = xfs_rmap_map(rcur, bno, blockcount, unwritten, &oinfo);
+               break;
+       case XFS_RMAP_FREE:
+       case XFS_RMAP_UNMAP:
+               error = xfs_rmap_unmap(rcur, bno, blockcount, unwritten,
+                               &oinfo);
+               break;
+       case XFS_RMAP_CONVERT:
+               error = xfs_rmap_convert(rcur, bno, blockcount, !unwritten,
+                               &oinfo);
+               break;
+       default:
+               ASSERT(0);
+               error = -EFSCORRUPTED;
+       }
+       return error;
+
+out_cur:
+       xfs_trans_brelse(tp, agbp);
+
+       return error;
+}
+
+/*
+ * Don't defer an rmap if we aren't an rmap filesystem.
+ */
+static bool
+xfs_rmap_update_is_needed(
+       struct xfs_mount        *mp)
+{
+       return xfs_sb_version_hasrmapbt(&mp->m_sb);
+}
+
+/*
+ * Record a rmap intent; the list is kept sorted first by AG and then by
+ * increasing age.
+ */
+static int
+__xfs_rmap_add(
+       struct xfs_mount                *mp,
+       struct xfs_defer_ops            *dfops,
+       enum xfs_rmap_intent_type       type,
+       __uint64_t                      owner,
+       int                             whichfork,
+       struct xfs_bmbt_irec            *bmap)
+{
+       struct xfs_rmap_intent  *ri;
+
+       trace_xfs_rmap_defer(mp, XFS_FSB_TO_AGNO(mp, bmap->br_startblock),
+                       type,
+                       XFS_FSB_TO_AGBNO(mp, bmap->br_startblock),
+                       owner, whichfork,
+                       bmap->br_startoff,
+                       bmap->br_blockcount,
+                       bmap->br_state);
+
+       ri = kmem_alloc(sizeof(struct xfs_rmap_intent), KM_SLEEP | KM_NOFS);
+       INIT_LIST_HEAD(&ri->ri_list);
+       ri->ri_type = type;
+       ri->ri_owner = owner;
+       ri->ri_whichfork = whichfork;
+       ri->ri_bmap = *bmap;
+
+       xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_RMAP, &ri->ri_list);
+       return 0;
+}
+
+/* Map an extent into a file. */
+int
+xfs_rmap_map_extent(
+       struct xfs_mount        *mp,
+       struct xfs_defer_ops    *dfops,
+       struct xfs_inode        *ip,
+       int                     whichfork,
+       struct xfs_bmbt_irec    *PREV)
+{
+       if (!xfs_rmap_update_is_needed(mp))
+               return 0;
+
+       return __xfs_rmap_add(mp, dfops, XFS_RMAP_MAP, ip->i_ino,
+                       whichfork, PREV);
+}
+
+/* Unmap an extent out of a file. */
+int
+xfs_rmap_unmap_extent(
+       struct xfs_mount        *mp,
+       struct xfs_defer_ops    *dfops,
+       struct xfs_inode        *ip,
+       int                     whichfork,
+       struct xfs_bmbt_irec    *PREV)
+{
+       if (!xfs_rmap_update_is_needed(mp))
+               return 0;
+
+       return __xfs_rmap_add(mp, dfops, XFS_RMAP_UNMAP, ip->i_ino,
+                       whichfork, PREV);
+}
+
+/* Convert a data fork extent from unwritten to real or vice versa. */
+int
+xfs_rmap_convert_extent(
+       struct xfs_mount        *mp,
+       struct xfs_defer_ops    *dfops,
+       struct xfs_inode        *ip,
+       int                     whichfork,
+       struct xfs_bmbt_irec    *PREV)
+{
+       if (!xfs_rmap_update_is_needed(mp))
+               return 0;
+
+       return __xfs_rmap_add(mp, dfops, XFS_RMAP_CONVERT, ip->i_ino,
+                       whichfork, PREV);
+}
+
+/* Schedule the creation of an rmap for non-file data. */
+int
+xfs_rmap_alloc_extent(
+       struct xfs_mount        *mp,
+       struct xfs_defer_ops    *dfops,
+       xfs_agnumber_t          agno,
+       xfs_agblock_t           bno,
+       xfs_extlen_t            len,
+       __uint64_t              owner)
+{
+       struct xfs_bmbt_irec    bmap;
+
+       if (!xfs_rmap_update_is_needed(mp))
+               return 0;
+
+       bmap.br_startblock = XFS_AGB_TO_FSB(mp, agno, bno);
+       bmap.br_blockcount = len;
+       bmap.br_startoff = 0;
+       bmap.br_state = XFS_EXT_NORM;
+
+       return __xfs_rmap_add(mp, dfops, XFS_RMAP_ALLOC, owner,
+                       XFS_DATA_FORK, &bmap);
+}
+
+/* Schedule the deletion of an rmap for non-file data. */
+int
+xfs_rmap_free_extent(
+       struct xfs_mount        *mp,
+       struct xfs_defer_ops    *dfops,
+       xfs_agnumber_t          agno,
+       xfs_agblock_t           bno,
+       xfs_extlen_t            len,
+       __uint64_t              owner)
+{
+       struct xfs_bmbt_irec    bmap;
+
+       if (!xfs_rmap_update_is_needed(mp))
+               return 0;
+
+       bmap.br_startblock = XFS_AGB_TO_FSB(mp, agno, bno);
+       bmap.br_blockcount = len;
+       bmap.br_startoff = 0;
+       bmap.br_state = XFS_EXT_NORM;
+
+       return __xfs_rmap_add(mp, dfops, XFS_RMAP_FREE, owner,
+                       XFS_DATA_FORK, &bmap);
+}