On Wed, Oct 20, 2021 at 1:30 AM Lorenz Bauer lmb@cloudflare.com wrote:

Add tests to exercise the behaviour of RENAME_EXCHANGE and RENAME_NOREPLACE on bpffs. The former checks that after an exchange the inode of two directories has changed. The latter checks that the source still exists after a failed rename.

Signed-off-by: Lorenz Bauer lmb@cloudflare.com

.../selftests/bpf/prog_tests/test_bpffs.c | 39 +++++++++++++++++++ 1 file changed, 39 insertions(+)

diff --git a/tools/testing/selftests/bpf/prog_tests/test_bpffs.c b/tools/testing/selftests/bpf/prog_tests/test_bpffs.c index 172c999e523c..9c28ae9589bf 100644 --- a/tools/testing/selftests/bpf/prog_tests/test_bpffs.c +++ b/tools/testing/selftests/bpf/prog_tests/test_bpffs.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2020 Facebook */ #define _GNU_SOURCE +#include <stdio.h> #include <sched.h> #include <sys/mount.h> #include <sys/stat.h> @@ -29,6 +30,7 @@ static int read_iter(char *file)

static int fn(void) {

•   struct stat a, b;
    int err, duration = 0;
  
    err = unshare(CLONE_NEWNS);
  

@@ -67,6 +69,43 @@ static int fn(void) err = read_iter(TDIR "/fs2/progs.debug"); if (CHECK(err, "reading " TDIR "/fs2/progs.debug", "failed\n")) goto out;

•   err = mkdir(TDIR "/fs1/a", 0777);
  

•   if (CHECK(err, "creating " TDIR "/fs1/a", "failed\n"))
  

•           goto out;
  

•   err = mkdir(TDIR "/fs1/a/1", 0777);
  

•   if (CHECK(err, "creating " TDIR "/fs1/a/1", "failed\n"))
  

•           goto out;
  

•   err = mkdir(TDIR "/fs1/b", 0777);
  

•   if (CHECK(err, "creating " TDIR "/fs1/b", "failed\n"))
  

•           goto out;
  

•   /* Check that RENAME_EXCHANGE works. */
  

•   err = stat(TDIR "/fs1/a", &a);
  

•   if (CHECK(err, "stat(" TDIR "/fs1/a)", "failed\n"))
  

•           goto out;
  

•   err = renameat2(0, TDIR "/fs1/a", 0, TDIR "/fs1/b", RENAME_EXCHANGE);
  

•   if (CHECK(err, "renameat2(RENAME_EXCHANGE)", "failed\n"))
  

•           goto out;
  

•   err = stat(TDIR "/fs1/b", &b);
  

•   if (CHECK(err, "stat(" TDIR "/fs1/b)", "failed\n"))
  

•           goto out;
  

•   if (CHECK(a.st_ino != b.st_ino, "b should have a's inode", "failed\n"))
  

•           goto out;
  

•   err = access(TDIR "/fs1/b/1", F_OK);
  

•   if (CHECK(err, "access(" TDIR "/fs1/b/1)", "failed\n"))
  

•           goto out;
  

•   /* Check that RENAME_NOREPLACE works. */
  

•   err = renameat2(0, TDIR "/fs1/b", 0, TDIR "/fs1/a", RENAME_NOREPLACE);
  

•   if (CHECK(!err, "renameat2(RENAME_NOREPLACE)", "succeeded\n")) {
  

•           err = -EINVAL;
  

•           goto out;
  

•   }
  

•   err = access(TDIR "/fs1/b", F_OK);
  

•   if (CHECK(err, "access(" TDIR "/fs1/b)", "failed\n"))
  

•           goto out;
  

Please use ASSERT_xxx() for new code.

out: umount(TDIR "/fs1"); umount(TDIR "/fs2"); -- 2.30.2