repair: reduce byte swap operations in scanfunc_allocbt

Store native endian version of the extent startblock and length in
local variables instead of converting them over and over again.

Signed-off-by: Barry Naujok <bnaujok@sgi.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>

diff --git a/repair/scan.c b/repair/scan.c
index f9915bb8e6718b7e407c8a91d3cef20a71b5a32d..2196f8152638ef1adccd8bbe82693e9f9fae4b8f 100644 (file)
--- a/repair/scan.c
+++ b/repair/scan.c
@@ -449,7 +449,6 @@ scanfunc_allocbt(
        __uint32_t              magic)
 {
        const char              *name;
-       xfs_agblock_t           b, e;
        int                     i;
        xfs_alloc_ptr_t         *pp;
        xfs_alloc_rec_t         *rp;
@@ -511,20 +510,21 @@ _("%s freespace btree block claimed (state %d), agno %d, bno %d, suspect %d\n"),
 
                rp = XFS_ALLOC_REC_ADDR(mp, block, 1);
                for (i = 0; i < numrecs; i++) {
-                       if (be32_to_cpu(rp[i].ar_blockcount) == 0 ||
-                           be32_to_cpu(rp[i].ar_startblock) == 0 ||
-                           !verify_agbno(mp, agno,
-                               be32_to_cpu(rp[i].ar_startblock)) ||
-                           be32_to_cpu(rp[i].ar_blockcount) >
-                                       MAXEXTLEN)
-                               continue;
+                       xfs_agblock_t           b, end;
+                       xfs_extlen_t            len;
+
+                       b = be32_to_cpu(rp[i].ar_startblock);
+                       len = be32_to_cpu(rp[i].ar_blockcount);
+                       end = b + len;
 
-                       e = be32_to_cpu(rp[i].ar_startblock) +
-                               be32_to_cpu(rp[i].ar_blockcount);
-                       if (!verify_agbno(mp, agno, e - 1))
+                       if (b == 0 || !verify_agbno(mp, agno, b))
+                               continue;
+                       if (len == 0 || len > MAXEXTLEN)
                                continue;
-                       for (b = be32_to_cpu(rp[i].ar_startblock);
-                            b < e; b++)  {
+                       if (!verify_agbno(mp, agno, end - 1))
+                               continue;
+
+                       for ( ; b < end; b++)  {
                                state = get_agbno_state(mp, agno, b);
                                switch (state) {
                                case XR_E_UNKNOWN:
@@ -581,6 +581,8 @@ _("%s freespace btree block claimed (state %d), agno %d, bno %d, suspect %d\n"),
        }
 
        for (i = 0; i < numrecs; i++)  {
+               xfs_agblock_t           bno = be32_to_cpu(pp[i]);
+
                /*
                 * XXX - put sibling detection right here.
                 * we know our sibling chain is good.  So as we go,
@@ -590,11 +592,11 @@ _("%s freespace btree block claimed (state %d), agno %d, bno %d, suspect %d\n"),
                 * pointer mismatch, try and extract as much data
                 * as possible.
                 */
-               if (be32_to_cpu(pp[i]) != 0 && verify_agbno(mp, agno,
-                                                       be32_to_cpu(pp[i])))
-                       scan_sbtree(be32_to_cpu(pp[i]), level, agno, suspect,
+               if (bno != 0 && verify_agbno(mp, agno, bno)) {
+                       scan_sbtree(bno, level, agno, suspect,
                                    (magic == XFS_ABTB_MAGIC) ?
                                     scanfunc_bno : scanfunc_cnt, 0);
+               }
        }
 }