text: // SPDX-License-Identifier: GPL-2.0
  /* Copyright (c) 2021 Facebook */
  #include <test_progs.h>
  #include <sys/types.h>
  #include <unistd.h>
  #include "find_vma.skel.h"
  #include "find_vma_fail1.skel.h"
  #include "find_vma_fail2.skel.h"
  
  static void test_and_reset_skel(struct find_vma *skel, int expected_find_zero_ret)
  {
  	ASSERT_EQ(skel->bss->found_vm_exec, 1, "found_vm_exec");
  	ASSERT_EQ(skel->data->find_addr_ret, 0, "find_addr_ret");
  	ASSERT_EQ(skel->data->find_zero_ret, expected_find_zero_ret, "find_zero_ret");
  	ASSERT_OK_PTR(strstr(skel->bss->d_iname, "test_progs"), "find_test_progs");
  
  	skel->bss->found_vm_exec = 0;
  	skel->data->find_addr_ret = -1;
  	skel->data->find_zero_ret = -1;
  	skel->bss->d_iname[0] = 0;
  }
  
  static int open_pe(void)
  {
  	struct perf_event_attr attr = {0};
  	int pfd;
  
  	/* create perf event */
  	attr.size = sizeof(attr);
  	attr.type = PERF_TYPE_HARDWARE;
  	attr.config = PERF_COUNT_HW_CPU_CYCLES;
  	attr.freq = 1;
  	attr.sample_freq = 4000;
  	pfd = syscall(__NR_perf_event_open, &attr, 0, -1, -1, PERF_FLAG_FD_CLOEXEC);
  
  	return pfd >= 0 ? pfd : -errno;
  }
  
  static void test_find_vma_pe(struct find_vma *skel)
  {
  	struct bpf_link *link = NULL;
  	volatile int j = 0;
  	int pfd, i;
  
  	pfd = open_pe();
  	if (pfd < 0) {
  		if (pfd == -ENOENT || pfd == -EOPNOTSUPP) {
  			printf("%s:SKIP:no PERF_COUNT_HW_CPU_CYCLES\n", __func__);
  			test__skip();
  			goto cleanup;
  		}
  		if (!ASSERT_GE(pfd, 0, "perf_event_open"))
  			goto cleanup;
  	}
  
  	link = bpf_program__attach_perf_event(skel->progs.handle_pe, pfd);
  	if (!ASSERT_OK_PTR(link, "attach_perf_event"))
  		goto cleanup;
  
  	for (i = 0; i < 1000000; ++i)
  		++j;
  
  	test_and_reset_skel(skel, -EBUSY /* in nmi, irq_work is busy */);
  cleanup:
  	bpf_link__destroy(link);
  	close(pfd);
  }
  
  static void test_find_vma_kprobe(struct find_vma *skel)
  {
  	int err;
  
  	err = find_vma__attach(skel);
  	if (!ASSERT_OK(err, "get_branch_snapshot__attach"))
  		return;
  
  	getpgid(skel->bss->target_pid);
  	test_and_reset_skel(skel, -ENOENT /* could not find vma for ptr 0 */);
  }
  
  static void test_illegal_write_vma(void)
  {
  	struct find_vma_fail1 *skel;
  
  	skel = find_vma_fail1__open_and_load();
  	if (!ASSERT_ERR_PTR(skel, "find_vma_fail1__open_and_load"))
  		find_vma_fail1__destroy(skel);
  }
  
  static void test_illegal_write_task(void)
  {
  	struct find_vma_fail2 *skel;
  
  	skel = find_vma_fail2__open_and_load();
  	if (!ASSERT_ERR_PTR(skel, "find_vma_fail2__open_and_load"))
  		find_vma_fail2__destroy(skel);
  }
  
  void serial_test_find_vma(void)
  {
  	struct find_vma *skel;
  
  	skel = find_vma__open_and_load();
  	if (!ASSERT_OK_PTR(skel, "find_vma__open_and_load"))
  		return;
  
  	skel->bss->target_pid = getpid();
  	skel->bss->addr = (__u64)(uintptr_t)test_find_vma_pe;
  
  	test_find_vma_pe(skel);
  	usleep(100000); /* allow the irq_work to finish */
  	test_find_vma_kprobe(skel);
  
  	find_vma__destroy(skel);
  	test_illegal_write_vma();
  	test_illegal_write_task();
  }
  