[PATCH] mkfs.xfs: fix ftype-vs-crc option combination testing

[Eric Sandeen <sandeen@xxxxxxxxxxx>]

mkfs.xfs got weird along the way; today it has different outcomes
depending on the order of option specification:

$ mkfs/mkfs.xfs -n ftype=1 -m crc=0 -dfile,name=fsfile,size=16g
cannot specify both crc and ftype
$ mkfs/mkfs.xfs -m crc=0 -n ftype=1 -dfile,name=fsfile,size=16g
<succeeds>

Somehow the tests got written as being constrained on what options
are specified - and in what order! - vs actually testing for
incompatible feature sets.

It's fine to specify both crc & ftype options, as long as it's an
allowed combination, so just test for the incompatible combination
(crc=1 and ftype=0) after all options have been processed.

Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
---

diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c
index 69d61c7..9042796 100644
--- a/mkfs/xfs_mkfs.c
+++ b/mkfs/xfs_mkfs.c
@@ -1477,11 +1477,6 @@ main(
                                        if (c < 0 || c > 1)
                                                illegal(value, "m crc");
                                        crcs_enabled = c;
-                                       if (nftype && crcs_enabled) {
-                                               fprintf(stderr,
-_("cannot specify both crc and ftype\n"));
-                                               usage();
-                                       }
                                        break;
                                case M_FINOBT:
                                        if (!value || *value == '\0')
@@ -1555,11 +1550,6 @@ _("cannot specify both crc and ftype\n"));
                                        if (nftype)
                                                respec('n', nopts, N_FTYPE);
                                        dirftype = atoi(value);
-                                       if (crcs_enabled) {
-                                               fprintf(stderr,
-_("cannot specify both crc and ftype\n"));
-                                               usage();
-                                       }
                                        nftype = 1;
                                        break;
                                default:
@@ -1714,6 +1704,10 @@ _("Minimum block size for CRC enabled filesystems is %d 
bytes.\n"),
                        XFS_MIN_CRC_BLOCKSIZE);
                usage();
        }
+       if (crcs_enabled && !dirftype) {
+               fprintf(stderr, _("cannot disable ftype with crcs enabled\n"));
+               usage();
+       }
 
        memset(&ft, 0, sizeof(ft));
        get_topology(&xi, &ft, force_overwrite);