xfs: Compute bmap extent alignments in a separate function

This commit moves over the code which computes stripe alignment and
extent size hint alignment into a separate function. Apart from
xfs_bmap_btalloc(), the new function will be used by another function
introduced in a future commit.

Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Chandan Babu R <chandanrlinux@gmail.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 0b15b1ff4bdd34b1331983acb8ce9bf199850317..8955a0a938d55aff41d709e1ec8ca42435e4edee 100644 (file)
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -3463,13 +3463,59 @@ xfs_bmap_btalloc_accounting(
                args->len);
 }
 
+static int
+xfs_bmap_compute_alignments(
+       struct xfs_bmalloca     *ap,
+       struct xfs_alloc_arg    *args)
+{
+       struct xfs_mount        *mp = args->mp;
+       xfs_extlen_t            align = 0; /* minimum allocation alignment */
+       int                     stripe_align = 0;
+       int                     error;
+
+       /* stripe alignment for allocation is determined by mount parameters */
+       if (mp->m_swidth && (mp->m_flags & XFS_MOUNT_SWALLOC))
+               stripe_align = mp->m_swidth;
+       else if (mp->m_dalign)
+               stripe_align = mp->m_dalign;
+
+       if (ap->flags & XFS_BMAPI_COWFORK)
+               align = xfs_get_cowextsz_hint(ap->ip);
+       else if (ap->datatype & XFS_ALLOC_USERDATA)
+               align = xfs_get_extsz_hint(ap->ip);
+       if (align) {
+               error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev,
+                                               align, 0, ap->eof, 0, ap->conv,
+                                               &ap->offset, &ap->length);
+               ASSERT(!error);
+               ASSERT(ap->length);
+       }
+
+       /* apply extent size hints if obtained earlier */
+       if (align) {
+               args->prod = align;
+               div_u64_rem(ap->offset, args->prod, &args->mod);
+               if (args->mod)
+                       args->mod = args->prod - args->mod;
+       } else if (mp->m_sb.sb_blocksize >= PAGE_SIZE) {
+               args->prod = 1;
+               args->mod = 0;
+       } else {
+               args->prod = PAGE_SIZE >> mp->m_sb.sb_blocklog;
+               div_u64_rem(ap->offset, args->prod, &args->mod);
+               if (args->mod)
+                       args->mod = args->prod - args->mod;
+       }
+
+       return stripe_align;
+}
+
 STATIC int
 xfs_bmap_btalloc(
        struct xfs_bmalloca     *ap)    /* bmap alloc argument struct */
 {
        xfs_mount_t     *mp;            /* mount point structure */
        xfs_alloctype_t atype = 0;      /* type for allocation routines */
-       xfs_extlen_t    align = 0;      /* minimum allocation alignment */
        xfs_agnumber_t  fb_agno;        /* ag number of ap->firstblock */
        xfs_agnumber_t  ag;
        xfs_alloc_arg_t args;
@@ -3489,25 +3535,11 @@ xfs_bmap_btalloc(
 
        mp = ap->ip->i_mount;
 
-       /* stripe alignment for allocation is determined by mount parameters */
-       stripe_align = 0;
-       if (mp->m_swidth && (mp->m_flags & XFS_MOUNT_SWALLOC))
-               stripe_align = mp->m_swidth;
-       else if (mp->m_dalign)
-               stripe_align = mp->m_dalign;
-
-       if (ap->flags & XFS_BMAPI_COWFORK)
-               align = xfs_get_cowextsz_hint(ap->ip);
-       else if (ap->datatype & XFS_ALLOC_USERDATA)
-               align = xfs_get_extsz_hint(ap->ip);
-       if (align) {
-               error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev,
-                                               align, 0, ap->eof, 0, ap->conv,
-                                               &ap->offset, &ap->length);
-               ASSERT(!error);
-               ASSERT(ap->length);
-       }
+       memset(&args, 0, sizeof(args));
+       args.tp = ap->tp;
+       args.mp = mp;
 
+       stripe_align = xfs_bmap_compute_alignments(ap, &args);
 
        nullfb = ap->tp->t_firstblock == NULLFSBLOCK;
        fb_agno = nullfb ? NULLAGNUMBER : XFS_FSB_TO_AGNO(mp,
@@ -3538,9 +3570,6 @@ xfs_bmap_btalloc(
         * Normal allocation, done through xfs_alloc_vextent.
         */
        tryagain = isaligned = 0;
-       memset(&args, 0, sizeof(args));
-       args.tp = ap->tp;
-       args.mp = mp;
        args.fsbno = ap->blkno;
        args.oinfo = XFS_RMAP_OINFO_SKIP_UPDATE;
 
@@ -3571,21 +3600,7 @@ xfs_bmap_btalloc(
                args.total = ap->total;
                args.minlen = ap->minlen;
        }
-       /* apply extent size hints if obtained earlier */
-       if (align) {
-               args.prod = align;
-               div_u64_rem(ap->offset, args.prod, &args.mod);
-               if (args.mod)
-                       args.mod = args.prod - args.mod;
-       } else if (mp->m_sb.sb_blocksize >= PAGE_SIZE) {
-               args.prod = 1;
-               args.mod = 0;
-       } else {
-               args.prod = PAGE_SIZE >> mp->m_sb.sb_blocklog;
-               div_u64_rem(ap->offset, args.prod, &args.mod);
-               if (args.mod)
-                       args.mod = args.prod - args.mod;
-       }
+
        /*
         * If we are not low on available data blocks, and the underlying
         * logical volume manager is a stripe, and the file offset is zero then