From: Alexei Starovoitov <ast@xxxxxxxxxx>
Add a test that mounts two bpffs instances and checks progs.debug
and maps.debug for sanity data.
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
---
.../selftests/bpf/prog_tests/test_bpffs.c | 94 +++++++++++++++++++
1 file changed, 94 insertions(+)
create mode 100644 tools/testing/selftests/bpf/prog_tests/test_bpffs.c
diff --git a/tools/testing/selftests/bpf/prog_tests/test_bpffs.c b/tools/testing/selftests/bpf/prog_tests/test_bpffs.c
new file mode 100644
index 000000000000..172c999e523c
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/test_bpffs.c
@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2020 Facebook */
+#define _GNU_SOURCE
+#include <sched.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <test_progs.h>
+
+#define TDIR "/sys/kernel/debug"
+
+static int read_iter(char *file)
+{
+ /* 1024 should be enough to get contiguous 4 "iter" letters at some point */
+ char buf[1024];
+ int fd, len;
+
+ fd = open(file, 0);
+ if (fd < 0)
+ return -1;
+ while ((len = read(fd, buf, sizeof(buf))) > 0)
+ if (strstr(buf, "iter")) {
+ close(fd);
+ return 0;
+ }
+ close(fd);
+ return -1;
+}
+
+static int fn(void)
+{
+ int err, duration = 0;
+
+ err = unshare(CLONE_NEWNS);
+ if (CHECK(err, "unshare", "failed: %d\n", errno))
+ goto out;
+
+ err = mount("", "/", "", MS_REC | MS_PRIVATE, NULL);
+ if (CHECK(err, "mount /", "failed: %d\n", errno))
+ goto out;
+
+ err = umount(TDIR);
+ if (CHECK(err, "umount " TDIR, "failed: %d\n", errno))
+ goto out;
+
+ err = mount("none", TDIR, "tmpfs", 0, NULL);
+ if (CHECK(err, "mount", "mount root failed: %d\n", errno))
+ goto out;
+
+ err = mkdir(TDIR "/fs1", 0777);
+ if (CHECK(err, "mkdir "TDIR"/fs1", "failed: %d\n", errno))
+ goto out;
+ err = mkdir(TDIR "/fs2", 0777);
+ if (CHECK(err, "mkdir "TDIR"/fs2", "failed: %d\n", errno))
+ goto out;
+
+ err = mount("bpf", TDIR "/fs1", "bpf", 0, NULL);
+ if (CHECK(err, "mount bpffs "TDIR"/fs1", "failed: %d\n", errno))
+ goto out;
+ err = mount("bpf", TDIR "/fs2", "bpf", 0, NULL);
+ if (CHECK(err, "mount bpffs " TDIR "/fs2", "failed: %d\n", errno))
+ goto out;
+
+ err = read_iter(TDIR "/fs1/maps.debug");
+ if (CHECK(err, "reading " TDIR "/fs1/maps.debug", "failed\n"))
+ goto out;
+ err = read_iter(TDIR "/fs2/progs.debug");
+ if (CHECK(err, "reading " TDIR "/fs2/progs.debug", "failed\n"))
+ goto out;
+out:
+ umount(TDIR "/fs1");
+ umount(TDIR "/fs2");
+ rmdir(TDIR "/fs1");
+ rmdir(TDIR "/fs2");
+ umount(TDIR);
+ exit(err);
+}
+
+void test_test_bpffs(void)
+{
+ int err, duration = 0, status = 0;
+ pid_t pid;
+
+ pid = fork();
+ if (CHECK(pid == -1, "clone", "clone failed %d", errno))
+ return;
+ if (pid == 0)
+ fn();
+ err = waitpid(pid, &status, 0);
+ if (CHECK(err == -1 && errno != ECHILD, "waitpid", "failed %d", errno))
+ return;
+ if (CHECK(WEXITSTATUS(status), "bpffs test ", "failed %d", WEXITSTATUS(status)))
+ return;
+}
--
2.23.0
