[XFS] implement generic xfs_btree_update
From: Dave Chinner <dgc@sgi.com>
The most complicated part here is the lastrec tracking for the alloc
btree. Most logic is in the update_lastrec method which has to do some
hopefully good enough dirty magic to maintain it.
[hch: split out from bigger patch and a rework of the lastrec
logic]
SGI-PV: 985583
SGI-Modid: xfs-linux-melb:xfs-kern:32194a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Bill O'Donnell <billodo@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>
diff --git a/fs/xfs/xfs_alloc_btree.c b/fs/xfs/xfs_alloc_btree.c
index 28c6a69..c5c3299 100644
--- a/fs/xfs/xfs_alloc_btree.c
+++ b/fs/xfs/xfs_alloc_btree.c
@@ -1661,76 +1661,6 @@
return 0;
}
-/*
- * Update the record referred to by cur, to the value given by [bno, len].
- * This either works (return 0) or gets an EFSCORRUPTED error.
- */
-int /* error */
-xfs_alloc_update(
- xfs_btree_cur_t *cur, /* btree cursor */
- xfs_agblock_t bno, /* starting block of extent */
- xfs_extlen_t len) /* length of extent */
-{
- xfs_alloc_block_t *block; /* btree block to update */
- int error; /* error return value */
- int ptr; /* current record number (updating) */
-
- ASSERT(len > 0);
- /*
- * Pick up the a.g. freelist struct and the current block.
- */
- block = XFS_BUF_TO_ALLOC_BLOCK(cur->bc_bufs[0]);
-#ifdef DEBUG
- if ((error = xfs_btree_check_sblock(cur, block, 0, cur->bc_bufs[0])))
- return error;
-#endif
- /*
- * Get the address of the rec to be updated.
- */
- ptr = cur->bc_ptrs[0];
- {
- xfs_alloc_rec_t *rp; /* pointer to updated record */
-
- rp = XFS_ALLOC_REC_ADDR(block, ptr, cur);
- /*
- * Fill in the new contents and log them.
- */
- rp->ar_startblock = cpu_to_be32(bno);
- rp->ar_blockcount = cpu_to_be32(len);
- xfs_alloc_log_recs(cur, cur->bc_bufs[0], ptr, ptr);
- }
- /*
- * If it's the by-size btree and it's the last leaf block and
- * it's the last record... then update the size of the longest
- * extent in the a.g., which we cache in the a.g. freelist header.
- */
- if (cur->bc_btnum == XFS_BTNUM_CNT &&
- be32_to_cpu(block->bb_rightsib) == NULLAGBLOCK &&
- ptr == be16_to_cpu(block->bb_numrecs)) {
- xfs_agf_t *agf; /* a.g. freespace header */
- xfs_agnumber_t seqno;
-
- agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
- seqno = be32_to_cpu(agf->agf_seqno);
- cur->bc_mp->m_perag[seqno].pagf_longest = len;
- agf->agf_longest = cpu_to_be32(len);
- xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp,
- XFS_AGF_LONGEST);
- }
- /*
- * Updating first record in leaf. Pass new key value up to our parent.
- */
- if (ptr == 1) {
- xfs_alloc_key_t key; /* key containing [bno, len] */
-
- key.ar_startblock = cpu_to_be32(bno);
- key.ar_blockcount = cpu_to_be32(len);
- if ((error = xfs_btree_updkey(cur, (union xfs_btree_key *)&key, 1)))
- return error;
- }
- return 0;
-}
-
STATIC struct xfs_btree_cur *
xfs_allocbt_dup_cursor(
struct xfs_btree_cur *cur)
@@ -1740,6 +1670,43 @@
cur->bc_btnum);
}
+/*
+ * Update the longest extent in the AGF
+ */
+STATIC void
+xfs_allocbt_update_lastrec(
+ struct xfs_btree_cur *cur,
+ struct xfs_btree_block *block,
+ union xfs_btree_rec *rec,
+ int ptr,
+ int reason)
+{
+ struct xfs_agf *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
+ xfs_agnumber_t seqno = be32_to_cpu(agf->agf_seqno);
+ __be32 len;
+
+ ASSERT(cur->bc_btnum == XFS_BTNUM_CNT);
+
+ switch (reason) {
+ case LASTREC_UPDATE:
+ /*
+ * If this is the last leaf block and it's the last record,
+ * then update the size of the longest extent in the AG.
+ */
+ if (ptr != xfs_btree_get_numrecs(block))
+ return;
+ len = rec->alloc.ar_blockcount;
+ break;
+ default:
+ ASSERT(0);
+ return;
+ }
+
+ agf->agf_longest = len;
+ cur->bc_mp->m_perag[seqno].pagf_longest = be32_to_cpu(len);
+ xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp, XFS_AGF_LONGEST);
+}
+
STATIC int
xfs_allocbt_get_maxrecs(
struct xfs_btree_cur *cur,
@@ -1864,6 +1831,7 @@
.key_len = sizeof(xfs_alloc_key_t),
.dup_cursor = xfs_allocbt_dup_cursor,
+ .update_lastrec = xfs_allocbt_update_lastrec,
.get_maxrecs = xfs_allocbt_get_maxrecs,
.init_key_from_rec = xfs_allocbt_init_key_from_rec,
.init_ptr_from_cur = xfs_allocbt_init_ptr_from_cur,
@@ -1902,6 +1870,8 @@
cur->bc_blocklog = mp->m_sb.sb_blocklog;
cur->bc_ops = &xfs_allocbt_ops;
+ if (btnum == XFS_BTNUM_CNT)
+ cur->bc_flags = XFS_BTREE_LASTREC_UPDATE;
cur->bc_private.a.agbp = agbp;
cur->bc_private.a.agno = agno;