xfs: refactor xfs_bmapi_allocate

Avoid duplicate userdata and data fork checks by restructuring the code
so we only have a helper for userdata allocations that combines these
checks in a straight foward way.  That also helps to obsoletes the
comments explaining what the code does as it is now clearly obvious.

Signed-off-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_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index 77e52874e8c5951ce64cd01f8630af5243ed7193..6af74f08b1c77c8df37fae2dc0c02556f227baa5 100644 (file)
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -3604,20 +3604,6 @@ xfs_bmap_btalloc(
        return 0;
 }
 
-/*
- * xfs_bmap_alloc is called by xfs_bmapi to allocate an extent for a file.
- * It figures out where to ask the underlying allocator to put the new extent.
- */
-STATIC int
-xfs_bmap_alloc(
-       struct xfs_bmalloca     *ap)    /* bmap alloc argument struct */
-{
-       if (XFS_IS_REALTIME_INODE(ap->ip) &&
-           xfs_alloc_is_userdata(ap->datatype))
-               return xfs_bmap_rtalloc(ap);
-       return xfs_bmap_btalloc(ap);
-}
-
 /* Trim extent to fit a logical block range. */
 void
 xfs_trim_extent(
@@ -3973,6 +3959,42 @@ out_unreserve_quota:
        return error;
 }
 
+static int
+xfs_bmap_alloc_userdata(
+       struct xfs_bmalloca     *bma)
+{
+       struct xfs_mount        *mp = bma->ip->i_mount;
+       int                     whichfork = xfs_bmapi_whichfork(bma->flags);
+       int                     error;
+
+       /*
+        * Set the data type being allocated. For the data fork, the first data
+        * in the file is treated differently to all other allocations. For the
+        * attribute fork, we only need to ensure the allocated range is not on
+        * the busy list.
+        */
+       bma->datatype = XFS_ALLOC_NOBUSY;
+       if (bma->flags & XFS_BMAPI_ZERO)
+               bma->datatype |= XFS_ALLOC_USERDATA_ZERO;
+       if (whichfork == XFS_DATA_FORK) {
+               if (bma->offset == 0)
+                       bma->datatype |= XFS_ALLOC_INITIAL_USER_DATA;
+               else
+                       bma->datatype |= XFS_ALLOC_USERDATA;
+
+               if (mp->m_dalign && bma->length >= mp->m_dalign) {
+                       error = xfs_bmap_isaeof(bma, whichfork);
+                       if (error)
+                               return error;
+               }
+
+               if (XFS_IS_REALTIME_INODE(bma->ip))
+                       return xfs_bmap_rtalloc(bma);
+       }
+
+       return xfs_bmap_btalloc(bma);
+}
+
 static int
 xfs_bmapi_allocate(
        struct xfs_bmalloca     *bma)
@@ -4000,43 +4022,18 @@ xfs_bmapi_allocate(
                                        bma->got.br_startoff - bma->offset);
        }
 
-       /*
-        * Set the data type being allocated. For the data fork, the first data
-        * in the file is treated differently to all other allocations. For the
-        * attribute fork, we only need to ensure the allocated range is not on
-        * the busy list.
-        */
-       if (!(bma->flags & XFS_BMAPI_METADATA)) {
-               bma->datatype = XFS_ALLOC_NOBUSY;
-               if (whichfork == XFS_DATA_FORK) {
-                       if (bma->offset == 0)
-                               bma->datatype |= XFS_ALLOC_INITIAL_USER_DATA;
-                       else
-                               bma->datatype |= XFS_ALLOC_USERDATA;
-               }
-               if (bma->flags & XFS_BMAPI_ZERO)
-                       bma->datatype |= XFS_ALLOC_USERDATA_ZERO;
-       }
-
-       bma->minlen = (bma->flags & XFS_BMAPI_CONTIG) ? bma->length : 1;
-
-       /*
-        * Only want to do the alignment at the eof if it is userdata and
-        * allocation length is larger than a stripe unit.
-        */
-       if (mp->m_dalign && bma->length >= mp->m_dalign &&
-           !(bma->flags & XFS_BMAPI_METADATA) && whichfork == XFS_DATA_FORK) {
-               error = xfs_bmap_isaeof(bma, whichfork);
-               if (error)
-                       return error;
-       }
+       if (bma->flags & XFS_BMAPI_CONTIG)
+               bma->minlen = bma->length;
+       else
+               bma->minlen = 1;
 
-       error = xfs_bmap_alloc(bma);
-       if (error)
+       if (bma->flags & XFS_BMAPI_METADATA)
+               error = xfs_bmap_btalloc(bma);
+       else
+               error = xfs_bmap_alloc_userdata(bma);
+       if (error || bma->blkno == NULLFSBLOCK)
                return error;
 
-       if (bma->blkno == NULLFSBLOCK)
-               return 0;
        if ((ifp->if_flags & XFS_IFBROOT) && !bma->cur)
                bma->cur = xfs_bmbt_init_cursor(mp, bma->tp, bma->ip, whichfork);
        /*