// 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, bool need_test)
{
        if (need_test) {
                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_SOFTWARE;
        attr.config = PERF_COUNT_SW_CPU_CLOCK;
        attr.freq = 1;
        attr.sample_freq = 1000;
        pfd = syscall(__NR_perf_event_open, &attr, 0, -1, -1, PERF_FLAG_FD_CLOEXEC);

        return pfd >= 0 ? pfd : -errno;
}

static bool find_vma_pe_condition(struct find_vma *skel)
{
        return skel->bss->found_vm_exec == 0 ||
                skel->data->find_addr_ret != 0 ||
                skel->data->find_zero_ret == -1 ||
                strcmp(skel->bss->d_iname, "test_progs") != 0;
}

static void test_find_vma_pe(struct find_vma *skel)
{
        struct bpf_link *link = NULL;
        volatile int j = 0;
        int pfd, i;
        const int one_bn = 1000000000;

        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 < one_bn && find_vma_pe_condition(skel); ++i)
                ++j;

        test_and_reset_skel(skel, -EBUSY /* in nmi, irq_work is busy */, i == one_bn);
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 */, true);
}

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);
        test_find_vma_kprobe(skel);

        find_vma__destroy(skel);
        test_illegal_write_vma();
        test_illegal_write_task();
}