[XFS] implement generic xfs_btree_get_rec

Not really much reason to make it generic given that it's so small, but
this is the last non-method in xfs_alloc_btree.c and xfs_ialloc_btree.c,
so it makes the whole btree implementation more structured.

SGI-PV: 985583

SGI-Modid: xfs-linux-melb:xfs-kern:32206a

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>

1 files changed, 21 insertions, 0 deletions

diff --git a/fs/xfs/xfs_alloc.c b/fs/xfs/xfs_alloc.c
index e9c70249d2c5..54fa69e27761 100644
--- a/fs/xfs/xfs_alloc.c
+++ b/fs/xfs/xfs_alloc.c
@@ -155,6 +155,27 @@ xfs_alloc_update(
 }
 
 /*
+ * Get the data from the pointed-to record.
+ */
+STATIC int                              /* error */
+xfs_alloc_get_rec(
+        struct xfs_btree_cur    *cur,   /* btree cursor */
+        xfs_agblock_t           *bno,   /* output: starting block of extent */
+        xfs_extlen_t            *len,   /* output: length of extent */
+        int                     *stat)  /* output: success/failure */
+{
+        union xfs_btree_rec     *rec;
+        int                     error;
+
+        error = xfs_btree_get_rec(cur, &rec, stat);
+        if (!error && *stat == 1) {
+                *bno = be32_to_cpu(rec->alloc.ar_startblock);
+                *len = be32_to_cpu(rec->alloc.ar_blockcount);
+        }
+        return error;
+}
+
+/*
  * Compute aligned version of the found extent.
  * Takes alignment and min length into account.
  */