xfs: clean up small allocation helper

xfs_alloc_ag_vextent_small() is kind of a mess. Clean it up in
preparation for future changes. No functional changes.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
index 1bf3e1c63e9863363d9f9d08b74678104d9c267f..795e39b13b0e30e23af7751e9f52b1312c61d83d 100644 (file)
--- a/fs/xfs/libxfs/xfs_alloc.c
+++ b/fs/xfs/libxfs/xfs_alloc.c
@@ -1583,92 +1583,80 @@ out_nominleft:
 }
 
 /*
- * Deal with the case where only small freespaces remain.
- * Either return the contents of the last freespace record,
- * or allocate space from the freelist if there is nothing in the tree.
+ * Deal with the case where only small freespaces remain. Either return the
+ * contents of the last freespace record, or allocate space from the freelist if
+ * there is nothing in the tree.
  */
 STATIC int                     /* error */
 xfs_alloc_ag_vextent_small(
-       xfs_alloc_arg_t *args,  /* allocation argument structure */
-       xfs_btree_cur_t *ccur,  /* by-size cursor */
-       xfs_agblock_t   *fbnop, /* result block number */
-       xfs_extlen_t    *flenp, /* result length */
-       int             *stat)  /* status: 0-freelist, 1-normal/none */
+       struct xfs_alloc_arg    *args,  /* allocation argument structure */
+       struct xfs_btree_cur    *ccur,  /* optional by-size cursor */
+       xfs_agblock_t           *fbnop, /* result block number */
+       xfs_extlen_t            *flenp, /* result length */
+       int                     *stat)  /* status: 0-freelist, 1-normal/none */
 {
-       int             error;
-       xfs_agblock_t   fbno;
-       xfs_extlen_t    flen;
-       int             i;
+       int                     error = 0;
+       xfs_agblock_t           fbno = NULLAGBLOCK;
+       xfs_extlen_t            flen = 0;
+       int                     i;
 
-       if ((error = xfs_btree_decrement(ccur, 0, &i)))
-               goto error0;
+       error = xfs_btree_decrement(ccur, 0, &i);
+       if (error)
+               goto error;
        if (i) {
-               if ((error = xfs_alloc_get_rec(ccur, &fbno, &flen, &i)))
-                       goto error0;
-               XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, error0);
-       }
-       /*
-        * Nothing in the btree, try the freelist.  Make sure
-        * to respect minleft even when pulling from the
-        * freelist.
-        */
-       else if (args->minlen == 1 && args->alignment == 1 &&
-                args->resv != XFS_AG_RESV_AGFL &&
-                (be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_flcount)
-                 > args->minleft)) {
-               error = xfs_alloc_get_freelist(args->tp, args->agbp, &fbno, 0);
+               error = xfs_alloc_get_rec(ccur, &fbno, &flen, &i);
                if (error)
-                       goto error0;
-               if (fbno != NULLAGBLOCK) {
-                       xfs_extent_busy_reuse(args->mp, args->agno, fbno, 1,
-                             xfs_alloc_allow_busy_reuse(args->datatype));
+                       goto error;
+               XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, error);
+               goto out;
+       }
 
-                       if (xfs_alloc_is_userdata(args->datatype)) {
-                               xfs_buf_t       *bp;
+       if (args->minlen != 1 || args->alignment != 1 ||
+           args->resv == XFS_AG_RESV_AGFL ||
+           (be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_flcount) <=
+            args->minleft))
+               goto out;
 
-                               bp = xfs_btree_get_bufs(args->mp, args->tp,
-                                       args->agno, fbno);
-                               if (!bp) {
-                                       error = -EFSCORRUPTED;
-                                       goto error0;
-                               }
-                               xfs_trans_binval(args->tp, bp);
-                       }
-                       args->len = 1;
-                       args->agbno = fbno;
-                       XFS_WANT_CORRUPTED_GOTO(args->mp,
-                               args->agbno + args->len <=
-                               be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length),
-                               error0);
-                       args->wasfromfl = 1;
-                       trace_xfs_alloc_small_freelist(args);
+       error = xfs_alloc_get_freelist(args->tp, args->agbp, &fbno, 0);
+       if (error)
+               goto error;
+       if (fbno == NULLAGBLOCK)
+               goto out;
 
-                       /*
-                        * If we're feeding an AGFL block to something that
-                        * doesn't live in the free space, we need to clear
-                        * out the OWN_AG rmap.
-                        */
-                       error = xfs_rmap_free(args->tp, args->agbp, args->agno,
-                                       fbno, 1, &XFS_RMAP_OINFO_AG);
-                       if (error)
-                               goto error0;
+       xfs_extent_busy_reuse(args->mp, args->agno, fbno, 1,
+                             xfs_alloc_allow_busy_reuse(args->datatype));
 
-                       *stat = 0;
-                       return 0;
+       if (xfs_alloc_is_userdata(args->datatype)) {
+               struct xfs_buf  *bp;
+
+               bp = xfs_btree_get_bufs(args->mp, args->tp, args->agno, fbno);
+               if (!bp) {
+                       error = -EFSCORRUPTED;
+                       goto error;
                }
-               /*
-                * Nothing in the freelist.
-                */
-               else
-                       flen = 0;
+               xfs_trans_binval(args->tp, bp);
        }
+       args->len = 1;
+       args->agbno = fbno;
+       XFS_WANT_CORRUPTED_GOTO(args->mp,
+               fbno < be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length),
+               error);
+       args->wasfromfl = 1;
+       trace_xfs_alloc_small_freelist(args);
+
        /*
-        * Can't allocate from the freelist for some reason.
+        * If we're feeding an AGFL block to something that doesn't live in the
+        * free space, we need to clear out the OWN_AG rmap.
         */
-       else {
-               fbno = NULLAGBLOCK;
-               flen = 0;
-       }
+       error = xfs_rmap_free(args->tp, args->agbp, args->agno, fbno, 1,
+                             &XFS_RMAP_OINFO_AG);
+       if (error)
+               goto error;
+
+       *stat = 0;
+       return 0;
+
+out:
        /*
         * Can't do the allocation, give up.
         */
@@ -1683,7 +1671,7 @@ xfs_alloc_ag_vextent_small(
        trace_xfs_alloc_small_done(args);
        return 0;
 
-error0:
+error:
        trace_xfs_alloc_small_error(args);
        return error;
 }