[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.c b/fs/xfs/xfs_alloc.c
index 6bda0ae..875e1ba 100644
--- a/fs/xfs/xfs_alloc.c
+++ b/fs/xfs/xfs_alloc.c
@@ -136,6 +136,23 @@
return xfs_btree_lookup(cur, XFS_LOOKUP_LE, stat);
}
+/*
+ * Update the record referred to by cur to the value given
+ * by [bno, len].
+ * This either works (return 0) or gets an EFSCORRUPTED error.
+ */
+STATIC int /* error */
+xfs_alloc_update(
+ struct xfs_btree_cur *cur, /* btree cursor */
+ xfs_agblock_t bno, /* starting block of extent */
+ xfs_extlen_t len) /* length of extent */
+{
+ union xfs_btree_rec rec;
+
+ rec.alloc.ar_startblock = cpu_to_be32(bno);
+ rec.alloc.ar_blockcount = cpu_to_be32(len);
+ return xfs_btree_update(cur, &rec);
+}
/*
* Compute aligned version of the found extent.