#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"
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, <rec, &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(<rec, 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, >rec, &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(>rec, 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, <rec);
+ 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, >rec);
+ 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,
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;
}
projects / linux-2.6-block.git / blobdiff