[src/trunk]: src/tests/fs/nullfs ``twistymount'' regression test for scenario...

[pooka <pooka%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/6d177ce93891
branches:  trunk
changeset: 755553:6d177ce93891
user:      pooka <pooka%NetBSD.org@localhost>
date:      Wed Jun 09 08:37:16 2010 +0000

description:
``twistymount'' regression test for scenario described in PR kern/43439

diffstat:

 tests/fs/nullfs/t_basic.c |  62 +++++++++++++++++++++++++++++++++++++++++-----
 1 files changed, 55 insertions(+), 7 deletions(-)

diffs (93 lines):

diff -r 70aaeea4195b -r 6d177ce93891 tests/fs/nullfs/t_basic.c
--- a/tests/fs/nullfs/t_basic.c Wed Jun 09 07:54:13 2010 +0000
+++ b/tests/fs/nullfs/t_basic.c Wed Jun 09 08:37:16 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: t_basic.c,v 1.2 2010/05/31 23:44:54 pooka Exp $        */
+/*     $NetBSD: t_basic.c,v 1.3 2010/06/09 08:37:16 pooka Exp $        */
 
 #include <sys/types.h>
 #include <sys/mount.h>
@@ -58,9 +58,20 @@
        return EPROGMISMATCH;
 }
 
+static void
+mountnull(const char *what, const char *mp, int flags)
+{
+       struct null_args nargs;
+
+       memset(&nargs, 0, sizeof(nargs));
+       nargs.nulla_target = __UNCONST(what);
+       if (rump_sys_mount(MOUNT_NULL, mp, flags, &nargs, sizeof(nargs)) == -1)
+               atf_tc_fail_errno("could not mount nullfs");
+
+}
+
 ATF_TC_BODY(basic, tc)
 {
-       struct null_args nargs;
        struct tmpfs_args targs;
        struct stat sb;
        int error;
@@ -78,10 +89,7 @@
        if (rump_sys_mount(MOUNT_TMPFS, "/td1", 0, &targs, sizeof(targs)) == -1)
                atf_tc_fail_errno("could not mount tmpfs td1");
 
-       memset(&nargs, 0, sizeof(nargs));
-       nargs.nulla_target = __UNCONST("/td1");
-       if (rump_sys_mount(MOUNT_NULL, "/td2", 0, &nargs, sizeof(nargs)) == -1)
-               atf_tc_fail_errno("could not mount nullfs");
+       mountnull("/td1", "/td2", 0);
 
        /* test unnull -> null */
        xput_tfile("/td1/tensti", "jeppe");
@@ -119,8 +127,48 @@
        /* done */
 }
 
+ATF_TC(twistymount);
+ATF_TC_HEAD(twistymount, tc)
+{
+
+       /* this is expected to fail until the PR is fixed */
+       atf_tc_set_md_var(tc, "descr", "\"recursive\" mounts deadlock"
+           " (kern/43439)");
+}
+
+/*
+ * Mapping to identifiers in kern/43439:
+ *  /td                = /home/current/pkgsrc
+ *  /td/dist   = /home/current/pkgsrc/distiles
+ *  /mp                = /usr/pkgsrc
+ *  /mp/dist   = /usr/pkgsrc/distfiles -- "created" by first null mount
+ */
+
+ATF_TC_BODY(twistymount, tc)
+{
+       int mkd = 0;
+
+       rump_init();
+
+       if (rump_sys_mkdir("/td", 0777) == -1)
+               atf_tc_fail_errno("mkdir %d", mkd++);
+       if (rump_sys_mkdir("/td/dist", 0777) == -1)
+               atf_tc_fail_errno("mkdir %d", mkd++);
+       if (rump_sys_mkdir("/mp", 0777) == -1)
+               atf_tc_fail_errno("mkdir %d", mkd++);
+
+       /* MNT_RDONLY doesn't matter, but just for compat with the PR */
+       mountnull("/td", "/mp", MNT_RDONLY);
+       mountnull("/td/dist", "/mp/dist", 0);
+
+       /* if we didn't get a locking-against-meself panic, we passed */
+}
+
 ATF_TP_ADD_TCS(tp)
 {
+
        ATF_TP_ADD_TC(tp, basic);
-       return 0; /*XXX?*/
+       ATF_TP_ADD_TC(tp, twistymount);
+
+       return atf_no_error();
 }