mkfs.xfs: allow specification of 0 data stripe width & unit

The "noalign" option works for this too, but it seems reasonable
to allow explicit specification of stripe unit and stripe width
to 0; today, doing so today makes the code think it's unspecified,
and so it goes ahead and detects stripe geometry and sets it in the
superblock.  That's unexpected and surprising.

Create a new flag that tracks whtether a geometry option has been
specified, and if it's set along with 0 values, treat it the
same as if "noalign" had been specified.

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

diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c
index a69190b9e8dd69e8cbe96dd8ba1a2182aab027e1..b5c3a57e686eaf59ee1dde95f06cab3eb4e01c7e 100644 (file)
--- a/mkfs/xfs_mkfs.c
+++ b/mkfs/xfs_mkfs.c
@@ -1419,6 +1419,7 @@ main(
        int                     dsw;
        int                     dsunit;
        int                     dswidth;
+       int                     dsflag;
        int                     force_overwrite;
        struct fsxattr          fsx;
        int                     ilflag;
@@ -1521,7 +1522,7 @@ main(
        dfile = logfile = rtfile = NULL;
        dsize = logsize = rtsize = rtextsize = protofile = NULL;
        dsu = dsw = dsunit = dswidth = lalign = lsu = lsunit = 0;
-       nodsflag = norsflag = 0;
+       dsflag = nodsflag = norsflag = 0;
        force_overwrite = 0;
        worst_freelist = 0;
        memset(&fsx, 0, sizeof(fsx));
@@ -1587,16 +1588,20 @@ main(
                                        break;
                                case D_SUNIT:
                                        dsunit = getnum(value, &dopts, D_SUNIT);
+                                       dsflag = 1;
                                        break;
                                case D_SWIDTH:
                                        dswidth = getnum(value, &dopts,
                                                         D_SWIDTH);
+                                       dsflag = 1;
                                        break;
                                case D_SU:
                                        dsu = getnum(value, &dopts, D_SU);
+                                       dsflag = 1;
                                        break;
                                case D_SW:
                                        dsw = getnum(value, &dopts, D_SW);
+                                       dsflag = 1;
                                        break;
                                case D_NOALIGN:
                                        nodsflag = getnum(value, &dopts,
@@ -2303,6 +2308,10 @@ _("rmapbt not supported with realtime devices\n"));
        calc_stripe_factors(dsu, dsw, sectorsize, lsu, lsectorsize,
                                &dsunit, &dswidth, &lsunit);
 
+       /* If sunit & swidth were manually specified as 0, same as noalign */
+       if (dsflag && !dsunit && !dswidth)
+               nodsflag = 1;
+
        xi.setblksize = sectorsize;
 
        /*