// SPDX-License-Identifier: GPL-2.0
/*
 * page_fault_test.c - Test stage 2 faults.
 *
 * This test tries different combinations of guest accesses (e.g., write,
 * S1PTW), backing source type (e.g., anon) and types of faults (e.g., read on
 * hugetlbfs with a hole). It checks that the expected handling method is
 * called (e.g., uffd faults with the right address and write/read flag).
 */
#include <linux/bitmap.h>
#include <fcntl.h>
#include <test_util.h>
#include <kvm_util.h>
#include <processor.h>
#include <asm/sysreg.h>
#include <linux/bitfield.h>
#include "guest_modes.h"
#include "userfaultfd_util.h"

/* Guest virtual addresses that point to the test page and its PTE. */
#define TEST_GVA                                0xc0000000
#define TEST_EXEC_GVA                           (TEST_GVA + 0x8)
#define TEST_PTE_GVA                            0xb0000000
#define TEST_DATA                               0x0123456789ABCDEF

static uint64_t *guest_test_memory = (uint64_t *)TEST_GVA;

#define CMD_NONE                                (0)
#define CMD_SKIP_TEST                           (1ULL << 1)
#define CMD_HOLE_PT                             (1ULL << 2)
#define CMD_HOLE_DATA                           (1ULL << 3)
#define CMD_CHECK_WRITE_IN_DIRTY_LOG            (1ULL << 4)
#define CMD_CHECK_S1PTW_WR_IN_DIRTY_LOG         (1ULL << 5)
#define CMD_CHECK_NO_WRITE_IN_DIRTY_LOG         (1ULL << 6)
#define CMD_CHECK_NO_S1PTW_WR_IN_DIRTY_LOG      (1ULL << 7)
#define CMD_SET_PTE_AF                          (1ULL << 8)

#define PREPARE_FN_NR                           10
#define CHECK_FN_NR                             10

static struct event_cnt {
        int mmio_exits;
        int fail_vcpu_runs;
        int uffd_faults;
        /* uffd_faults is incremented from multiple threads. */
        pthread_mutex_t uffd_faults_mutex;
} events;

struct test_desc {
        const char *name;
        uint64_t mem_mark_cmd;
        /* Skip the test if any prepare function returns false */
        bool (*guest_prepare[PREPARE_FN_NR])(void);
        void (*guest_test)(void);
        void (*guest_test_check[CHECK_FN_NR])(void);
        uffd_handler_t uffd_pt_handler;
        uffd_handler_t uffd_data_handler;
        void (*dabt_handler)(struct ex_regs *regs);
        void (*iabt_handler)(struct ex_regs *regs);
        void (*mmio_handler)(struct kvm_vm *vm, struct kvm_run *run);
        void (*fail_vcpu_run_handler)(int ret);
        uint32_t pt_memslot_flags;
        uint32_t data_memslot_flags;
        bool skip;
        struct event_cnt expected_events;
};

struct test_params {
        enum vm_mem_backing_src_type src_type;
        struct test_desc *test_desc;
};

static inline void flush_tlb_page(uint64_t vaddr)
{
        uint64_t page = vaddr >> 12;

        dsb(ishst);
        asm volatile("tlbi vaae1is, %0" :: "r" (page));
        dsb(ish);
        isb();
}

static void guest_write64(void)
{
        uint64_t val;

        WRITE_ONCE(*guest_test_memory, TEST_DATA);
        val = READ_ONCE(*guest_test_memory);
        GUEST_ASSERT_EQ(val, TEST_DATA);
}

/* Check the system for atomic instructions. */
static bool guest_check_lse(void)
{
        uint64_t isar0 = read_sysreg(id_aa64isar0_el1);
        uint64_t atomic;

        atomic = FIELD_GET(ID_AA64ISAR0_EL1_ATOMIC, isar0);
        return atomic >= 2;
}

static bool guest_check_dc_zva(void)
{
        uint64_t dczid = read_sysreg(dczid_el0);
        uint64_t dzp = FIELD_GET(DCZID_EL0_DZP, dczid);

        return dzp == 0;
}

/* Compare and swap instruction. */
static void guest_cas(void)
{
        uint64_t val;

        GUEST_ASSERT(guest_check_lse());
        asm volatile(".arch_extension lse\n"
                     "casal %0, %1, [%2]\n"
                     :: "r" (0ul), "r" (TEST_DATA), "r" (guest_test_memory));
        val = READ_ONCE(*guest_test_memory);
        GUEST_ASSERT_EQ(val, TEST_DATA);
}

static void guest_read64(void)
{
        uint64_t val;

        val = READ_ONCE(*guest_test_memory);
        GUEST_ASSERT_EQ(val, 0);
}

/* Address translation instruction */
static void guest_at(void)
{
        uint64_t par;

        asm volatile("at s1e1r, %0" :: "r" (guest_test_memory));
        isb();
        par = read_sysreg(par_el1);

        /* Bit 1 indicates whether the AT was successful */
        GUEST_ASSERT_EQ(par & 1, 0);
}

/*
 * The size of the block written by "dc zva" is guaranteed to be between (2 <<
 * 0) and (2 << 9), which is safe in our case as we need the write to happen
 * for at least a word, and not more than a page.
 */
static void guest_dc_zva(void)
{
        uint16_t val;

        asm volatile("dc zva, %0" :: "r" (guest_test_memory));
        dsb(ish);
        val = READ_ONCE(*guest_test_memory);
        GUEST_ASSERT_EQ(val, 0);
}

/*
 * Pre-indexing loads and stores don't have a valid syndrome (ESR_EL2.ISV==0).
 * And that's special because KVM must take special care with those: they
 * should still count as accesses for dirty logging or user-faulting, but
 * should be handled differently on mmio.
 */
static void guest_ld_preidx(void)
{
        uint64_t val;
        uint64_t addr = TEST_GVA - 8;

        /*
         * This ends up accessing "TEST_GVA + 8 - 8", where "TEST_GVA - 8" is
         * in a gap between memslots not backing by anything.
         */
        asm volatile("ldr %0, [%1, #8]!"
                     : "=r" (val), "+r" (addr));
        GUEST_ASSERT_EQ(val, 0);
        GUEST_ASSERT_EQ(addr, TEST_GVA);
}

static void guest_st_preidx(void)
{
        uint64_t val = TEST_DATA;
        uint64_t addr = TEST_GVA - 8;

        asm volatile("str %0, [%1, #8]!"
                     : "+r" (val), "+r" (addr));

        GUEST_ASSERT_EQ(addr, TEST_GVA);
        val = READ_ONCE(*guest_test_memory);
}

static bool guest_set_ha(void)
{
        uint64_t mmfr1 = read_sysreg(id_aa64mmfr1_el1);
        uint64_t hadbs, tcr;

        /* Skip if HA is not supported. */
        hadbs = FIELD_GET(ID_AA64MMFR1_EL1_HAFDBS, mmfr1);
        if (hadbs == 0)
                return false;

        tcr = read_sysreg(tcr_el1) | TCR_HA;
        write_sysreg(tcr, tcr_el1);
        isb();

        return true;
}

static bool guest_clear_pte_af(void)
{
        *((uint64_t *)TEST_PTE_GVA) &= ~PTE_AF;
        flush_tlb_page(TEST_GVA);

        return true;
}

static void guest_check_pte_af(void)
{
        dsb(ish);
        GUEST_ASSERT_EQ(*((uint64_t *)TEST_PTE_GVA) & PTE_AF, PTE_AF);
}

static void guest_check_write_in_dirty_log(void)
{
        GUEST_SYNC(CMD_CHECK_WRITE_IN_DIRTY_LOG);
}

static void guest_check_no_write_in_dirty_log(void)
{
        GUEST_SYNC(CMD_CHECK_NO_WRITE_IN_DIRTY_LOG);
}

static void guest_check_s1ptw_wr_in_dirty_log(void)
{
        GUEST_SYNC(CMD_CHECK_S1PTW_WR_IN_DIRTY_LOG);
}

static void guest_check_no_s1ptw_wr_in_dirty_log(void)
{
        GUEST_SYNC(CMD_CHECK_NO_S1PTW_WR_IN_DIRTY_LOG);
}

static void guest_exec(void)
{
        int (*code)(void) = (int (*)(void))TEST_EXEC_GVA;
        int ret;

        ret = code();
        GUEST_ASSERT_EQ(ret, 0x77);
}

static bool guest_prepare(struct test_desc *test)
{
        bool (*prepare_fn)(void);
        int i;

        for (i = 0; i < PREPARE_FN_NR; i++) {
                prepare_fn = test->guest_prepare[i];
                if (prepare_fn && !prepare_fn())
                        return false;
        }

        return true;
}

static void guest_test_check(struct test_desc *test)
{
        void (*check_fn)(void);
        int i;

        for (i = 0; i < CHECK_FN_NR; i++) {
                check_fn = test->guest_test_check[i];
                if (check_fn)
                        check_fn();
        }
}

static void guest_code(struct test_desc *test)
{
        if (!guest_prepare(test))
                GUEST_SYNC(CMD_SKIP_TEST);

        GUEST_SYNC(test->mem_mark_cmd);

        if (test->guest_test)
                test->guest_test();

        guest_test_check(test);
        GUEST_DONE();
}

static void no_dabt_handler(struct ex_regs *regs)
{
        GUEST_FAIL("Unexpected dabt, far_el1 = 0x%lx", read_sysreg(far_el1));
}

static void no_iabt_handler(struct ex_regs *regs)
{
        GUEST_FAIL("Unexpected iabt, pc = 0x%lx", regs->pc);
}

static struct uffd_args {
        char *copy;
        void *hva;
        uint64_t paging_size;
} pt_args, data_args;

/* Returns true to continue the test, and false if it should be skipped. */
static int uffd_generic_handler(int uffd_mode, int uffd, struct uffd_msg *msg,
                                struct uffd_args *args)
{
        uint64_t addr = msg->arg.pagefault.address;
        uint64_t flags = msg->arg.pagefault.flags;
        struct uffdio_copy copy;
        int ret;

        TEST_ASSERT(uffd_mode == UFFDIO_REGISTER_MODE_MISSING,
                    "The only expected UFFD mode is MISSING");
        TEST_ASSERT_EQ(addr, (uint64_t)args->hva);

        pr_debug("uffd fault: addr=%p write=%d\n",
                 (void *)addr, !!(flags & UFFD_PAGEFAULT_FLAG_WRITE));

        copy.src = (uint64_t)args->copy;
        copy.dst = addr;
        copy.len = args->paging_size;
        copy.mode = 0;

        ret = ioctl(uffd, UFFDIO_COPY, &copy);
        if (ret == -1) {
                pr_info("Failed UFFDIO_COPY in 0x%lx with errno: %d\n",
                        addr, errno);
                return ret;
        }

        pthread_mutex_lock(&events.uffd_faults_mutex);
        events.uffd_faults += 1;
        pthread_mutex_unlock(&events.uffd_faults_mutex);
        return 0;
}

static int uffd_pt_handler(int mode, int uffd, struct uffd_msg *msg)
{
        return uffd_generic_handler(mode, uffd, msg, &pt_args);
}

static int uffd_data_handler(int mode, int uffd, struct uffd_msg *msg)
{
        return uffd_generic_handler(mode, uffd, msg, &data_args);
}

static void setup_uffd_args(struct userspace_mem_region *region,
                            struct uffd_args *args)
{
        args->hva = (void *)region->region.userspace_addr;
        args->paging_size = region->region.memory_size;

        args->copy = malloc(args->paging_size);
        TEST_ASSERT(args->copy, "Failed to allocate data copy.");
        memcpy(args->copy, args->hva, args->paging_size);
}

static void setup_uffd(struct kvm_vm *vm, struct test_params *p,
                       struct uffd_desc **pt_uffd, struct uffd_desc **data_uffd)
{
        struct test_desc *test = p->test_desc;
        int uffd_mode = UFFDIO_REGISTER_MODE_MISSING;

        setup_uffd_args(vm_get_mem_region(vm, MEM_REGION_PT), &pt_args);
        setup_uffd_args(vm_get_mem_region(vm, MEM_REGION_TEST_DATA), &data_args);

        *pt_uffd = NULL;
        if (test->uffd_pt_handler)
                *pt_uffd = uffd_setup_demand_paging(uffd_mode, 0,
                                                    pt_args.hva,
                                                    pt_args.paging_size,
                                                    1, test->uffd_pt_handler);

        *data_uffd = NULL;
        if (test->uffd_data_handler)
                *data_uffd = uffd_setup_demand_paging(uffd_mode, 0,
                                                      data_args.hva,
                                                      data_args.paging_size,
                                                      1, test->uffd_data_handler);
}

static void free_uffd(struct test_desc *test, struct uffd_desc *pt_uffd,
                      struct uffd_desc *data_uffd)
{
        if (test->uffd_pt_handler)
                uffd_stop_demand_paging(pt_uffd);
        if (test->uffd_data_handler)
                uffd_stop_demand_paging(data_uffd);

        free(pt_args.copy);
        free(data_args.copy);
}

static int uffd_no_handler(int mode, int uffd, struct uffd_msg *msg)
{
        TEST_FAIL("There was no UFFD fault expected.");
        return -1;
}

/* Returns false if the test should be skipped. */
static bool punch_hole_in_backing_store(struct kvm_vm *vm,
                                        struct userspace_mem_region *region)
{
        void *hva = (void *)region->region.userspace_addr;
        uint64_t paging_size = region->region.memory_size;
        int ret, fd = region->fd;

        if (fd != -1) {
                ret = fallocate(fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
                                0, paging_size);
                TEST_ASSERT(ret == 0, "fallocate failed");
        } else {
                ret = madvise(hva, paging_size, MADV_DONTNEED);
                TEST_ASSERT(ret == 0, "madvise failed");
        }

        return true;
}

static void mmio_on_test_gpa_handler(struct kvm_vm *vm, struct kvm_run *run)
{
        struct userspace_mem_region *region;
        void *hva;

        region = vm_get_mem_region(vm, MEM_REGION_TEST_DATA);
        hva = (void *)region->region.userspace_addr;

        TEST_ASSERT_EQ(run->mmio.phys_addr, region->region.guest_phys_addr);

        memcpy(hva, run->mmio.data, run->mmio.len);
        events.mmio_exits += 1;
}

static void mmio_no_handler(struct kvm_vm *vm, struct kvm_run *run)
{
        uint64_t data;

        memcpy(&data, run->mmio.data, sizeof(data));
        pr_debug("addr=%lld len=%d w=%d data=%lx\n",
                 run->mmio.phys_addr, run->mmio.len,
                 run->mmio.is_write, data);
        TEST_FAIL("There was no MMIO exit expected.");
}

static bool check_write_in_dirty_log(struct kvm_vm *vm,
                                     struct userspace_mem_region *region,
                                     uint64_t host_pg_nr)
{
        unsigned long *bmap;
        bool first_page_dirty;
        uint64_t size = region->region.memory_size;

        /* getpage_size() is not always equal to vm->page_size */
        bmap = bitmap_zalloc(size / getpagesize());
        kvm_vm_get_dirty_log(vm, region->region.slot, bmap);
        first_page_dirty = test_bit(host_pg_nr, bmap);
        free(bmap);
        return first_page_dirty;
}

/* Returns true to continue the test, and false if it should be skipped. */
static bool handle_cmd(struct kvm_vm *vm, int cmd)
{
        struct userspace_mem_region *data_region, *pt_region;
        bool continue_test = true;
        uint64_t pte_gpa, pte_pg;

        data_region = vm_get_mem_region(vm, MEM_REGION_TEST_DATA);
        pt_region = vm_get_mem_region(vm, MEM_REGION_PT);
        pte_gpa = addr_hva2gpa(vm, virt_get_pte_hva(vm, TEST_GVA));
        pte_pg = (pte_gpa - pt_region->region.guest_phys_addr) / getpagesize();

        if (cmd == CMD_SKIP_TEST)
                continue_test = false;

        if (cmd & CMD_HOLE_PT)
                continue_test = punch_hole_in_backing_store(vm, pt_region);
        if (cmd & CMD_HOLE_DATA)
                continue_test = punch_hole_in_backing_store(vm, data_region);
        if (cmd & CMD_CHECK_WRITE_IN_DIRTY_LOG)
                TEST_ASSERT(check_write_in_dirty_log(vm, data_region, 0),
                            "Missing write in dirty log");
        if (cmd & CMD_CHECK_S1PTW_WR_IN_DIRTY_LOG)
                TEST_ASSERT(check_write_in_dirty_log(vm, pt_region, pte_pg),
                            "Missing s1ptw write in dirty log");
        if (cmd & CMD_CHECK_NO_WRITE_IN_DIRTY_LOG)
                TEST_ASSERT(!check_write_in_dirty_log(vm, data_region, 0),
                            "Unexpected write in dirty log");
        if (cmd & CMD_CHECK_NO_S1PTW_WR_IN_DIRTY_LOG)
                TEST_ASSERT(!check_write_in_dirty_log(vm, pt_region, pte_pg),
                            "Unexpected s1ptw write in dirty log");

        return continue_test;
}

void fail_vcpu_run_no_handler(int ret)
{
        TEST_FAIL("Unexpected vcpu run failure");
}

void fail_vcpu_run_mmio_no_syndrome_handler(int ret)
{
        TEST_ASSERT(errno == ENOSYS,
                    "The mmio handler should have returned not implemented.");
        events.fail_vcpu_runs += 1;
}

typedef uint32_t aarch64_insn_t;
extern aarch64_insn_t __exec_test[2];

noinline void __return_0x77(void)
{
        asm volatile("__exec_test: mov x0, #0x77\n"
                     "ret\n");
}

/*
 * Note that this function runs on the host before the test VM starts: there's
 * no need to sync the D$ and I$ caches.
 */
static void load_exec_code_for_test(struct kvm_vm *vm)
{
        uint64_t *code;
        struct userspace_mem_region *region;
        void *hva;

        region = vm_get_mem_region(vm, MEM_REGION_TEST_DATA);
        hva = (void *)region->region.userspace_addr;

        assert(TEST_EXEC_GVA > TEST_GVA);
        code = hva + TEST_EXEC_GVA - TEST_GVA;
        memcpy(code, __exec_test, sizeof(__exec_test));
}

static void setup_abort_handlers(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
                                 struct test_desc *test)
{
        vm_init_descriptor_tables(vm);
        vcpu_init_descriptor_tables(vcpu);

        vm_install_sync_handler(vm, VECTOR_SYNC_CURRENT,
                                ESR_ELx_EC_DABT_CUR, no_dabt_handler);
        vm_install_sync_handler(vm, VECTOR_SYNC_CURRENT,
                                ESR_ELx_EC_IABT_CUR, no_iabt_handler);
}

static void setup_gva_maps(struct kvm_vm *vm)
{
        struct userspace_mem_region *region;
        uint64_t pte_gpa;

        region = vm_get_mem_region(vm, MEM_REGION_TEST_DATA);
        /* Map TEST_GVA first. This will install a new PTE. */
        virt_pg_map(vm, TEST_GVA, region->region.guest_phys_addr);
        /* Then map TEST_PTE_GVA to the above PTE. */
        pte_gpa = addr_hva2gpa(vm, virt_get_pte_hva(vm, TEST_GVA));
        virt_pg_map(vm, TEST_PTE_GVA, pte_gpa);
}

enum pf_test_memslots {
        CODE_AND_DATA_MEMSLOT,
        PAGE_TABLE_MEMSLOT,
        TEST_DATA_MEMSLOT,
};

/*
 * Create a memslot for code and data at pfn=0, and test-data and PT ones
 * at max_gfn.
 */
static void setup_memslots(struct kvm_vm *vm, struct test_params *p)
{
        uint64_t backing_src_pagesz = get_backing_src_pagesz(p->src_type);
        uint64_t guest_page_size = vm->page_size;
        uint64_t max_gfn = vm_compute_max_gfn(vm);
        /* Enough for 2M of code when using 4K guest pages. */
        uint64_t code_npages = 512;
        uint64_t pt_size, data_size, data_gpa;

        /*
         * This test requires 1 pgd, 2 pud, 4 pmd, and 6 pte pages when using
         * VM_MODE_P48V48_4K. Note that the .text takes ~1.6MBs.  That's 13
         * pages. VM_MODE_P48V48_4K is the mode with most PT pages; let's use
         * twice that just in case.
         */
        pt_size = 26 * guest_page_size;

        /* memslot sizes and gpa's must be aligned to the backing page size */
        pt_size = align_up(pt_size, backing_src_pagesz);
        data_size = align_up(guest_page_size, backing_src_pagesz);
        data_gpa = (max_gfn * guest_page_size) - data_size;
        data_gpa = align_down(data_gpa, backing_src_pagesz);

        vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 0,
                                    CODE_AND_DATA_MEMSLOT, code_npages, 0);
        vm->memslots[MEM_REGION_CODE] = CODE_AND_DATA_MEMSLOT;
        vm->memslots[MEM_REGION_DATA] = CODE_AND_DATA_MEMSLOT;

        vm_userspace_mem_region_add(vm, p->src_type, data_gpa - pt_size,
                                    PAGE_TABLE_MEMSLOT, pt_size / guest_page_size,
                                    p->test_desc->pt_memslot_flags);
        vm->memslots[MEM_REGION_PT] = PAGE_TABLE_MEMSLOT;

        vm_userspace_mem_region_add(vm, p->src_type, data_gpa, TEST_DATA_MEMSLOT,
                                    data_size / guest_page_size,
                                    p->test_desc->data_memslot_flags);
        vm->memslots[MEM_REGION_TEST_DATA] = TEST_DATA_MEMSLOT;
}

static void setup_ucall(struct kvm_vm *vm)
{
        struct userspace_mem_region *region = vm_get_mem_region(vm, MEM_REGION_TEST_DATA);

        ucall_init(vm, region->region.guest_phys_addr + region->region.memory_size);
}

static void setup_default_handlers(struct test_desc *test)
{
        if (!test->mmio_handler)
                test->mmio_handler = mmio_no_handler;

        if (!test->fail_vcpu_run_handler)
                test->fail_vcpu_run_handler = fail_vcpu_run_no_handler;
}

static void check_event_counts(struct test_desc *test)
{
        TEST_ASSERT_EQ(test->expected_events.uffd_faults, events.uffd_faults);
        TEST_ASSERT_EQ(test->expected_events.mmio_exits, events.mmio_exits);
        TEST_ASSERT_EQ(test->expected_events.fail_vcpu_runs, events.fail_vcpu_runs);
}

static void print_test_banner(enum vm_guest_mode mode, struct test_params *p)
{
        struct test_desc *test = p->test_desc;

        pr_debug("Test: %s\n", test->name);
        pr_debug("Testing guest mode: %s\n", vm_guest_mode_string(mode));
        pr_debug("Testing memory backing src type: %s\n",
                 vm_mem_backing_src_alias(p->src_type)->name);
}

static void reset_event_counts(void)
{
        memset(&events, 0, sizeof(events));
}

/*
 * This function either succeeds, skips the test (after setting test->skip), or
 * fails with a TEST_FAIL that aborts all tests.
 */
static void vcpu_run_loop(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
                          struct test_desc *test)
{
        struct kvm_run *run;
        struct ucall uc;
        int ret;

        run = vcpu->run;

        for (;;) {
                ret = _vcpu_run(vcpu);
                if (ret) {
                        test->fail_vcpu_run_handler(ret);
                        goto done;
                }

                switch (get_ucall(vcpu, &uc)) {
                case UCALL_SYNC:
                        if (!handle_cmd(vm, uc.args[1])) {
                                test->skip = true;
                                goto done;
                        }
                        break;
                case UCALL_ABORT:
                        REPORT_GUEST_ASSERT(uc);
                        break;
                case UCALL_DONE:
                        goto done;
                case UCALL_NONE:
                        if (run->exit_reason == KVM_EXIT_MMIO)
                                test->mmio_handler(vm, run);
                        break;
                default:
                        TEST_FAIL("Unknown ucall %lu", uc.cmd);
                }
        }

done:
        pr_debug(test->skip ? "Skipped.\n" : "Done.\n");
}

static void run_test(enum vm_guest_mode mode, void *arg)
{
        struct test_params *p = (struct test_params *)arg;
        struct test_desc *test = p->test_desc;
        struct kvm_vm *vm;
        struct kvm_vcpu *vcpu;
        struct uffd_desc *pt_uffd, *data_uffd;

        print_test_banner(mode, p);

        vm = ____vm_create(VM_SHAPE(mode));
        setup_memslots(vm, p);
        kvm_vm_elf_load(vm, program_invocation_name);
        setup_ucall(vm);
        vcpu = vm_vcpu_add(vm, 0, guest_code);

        setup_gva_maps(vm);

        reset_event_counts();

        /*
         * Set some code in the data memslot for the guest to execute (only
         * applicable to the EXEC tests). This has to be done before
         * setup_uffd() as that function copies the memslot data for the uffd
         * handler.
         */
        load_exec_code_for_test(vm);
        setup_uffd(vm, p, &pt_uffd, &data_uffd);
        setup_abort_handlers(vm, vcpu, test);
        setup_default_handlers(test);
        vcpu_args_set(vcpu, 1, test);

        vcpu_run_loop(vm, vcpu, test);

        kvm_vm_free(vm);
        free_uffd(test, pt_uffd, data_uffd);

        /*
         * Make sure we check the events after the uffd threads have exited,
         * which means they updated their respective event counters.
         */
        if (!test->skip)
                check_event_counts(test);
}

static void help(char *name)
{
        puts("");
        printf("usage: %s [-h] [-s mem-type]\n", name);
        puts("");
        guest_modes_help();
        backing_src_help("-s");
        puts("");
}

#define SNAME(s)                        #s
#define SCAT2(a, b)                     SNAME(a ## _ ## b)
#define SCAT3(a, b, c)                  SCAT2(a, SCAT2(b, c))
#define SCAT4(a, b, c, d)               SCAT2(a, SCAT3(b, c, d))

#define _CHECK(_test)                   _CHECK_##_test
#define _PREPARE(_test)                 _PREPARE_##_test
#define _PREPARE_guest_read64           NULL
#define _PREPARE_guest_ld_preidx        NULL
#define _PREPARE_guest_write64          NULL
#define _PREPARE_guest_st_preidx        NULL
#define _PREPARE_guest_exec             NULL
#define _PREPARE_guest_at               NULL
#define _PREPARE_guest_dc_zva           guest_check_dc_zva
#define _PREPARE_guest_cas              guest_check_lse

/* With or without access flag checks */
#define _PREPARE_with_af                guest_set_ha, guest_clear_pte_af
#define _PREPARE_no_af                  NULL
#define _CHECK_with_af                  guest_check_pte_af
#define _CHECK_no_af                    NULL

/* Performs an access and checks that no faults were triggered. */
#define TEST_ACCESS(_access, _with_af, _mark_cmd)                               \
{                                                                               \
        .name                   = SCAT3(_access, _with_af, #_mark_cmd),         \
        .guest_prepare          = { _PREPARE(_with_af),                         \
                                    _PREPARE(_access) },                        \
        .mem_mark_cmd           = _mark_cmd,                                    \
        .guest_test             = _access,                                      \
        .guest_test_check       = { _CHECK(_with_af) },                         \
        .expected_events        = { 0 },                                        \
}

#define TEST_UFFD(_access, _with_af, _mark_cmd,                                 \
                  _uffd_data_handler, _uffd_pt_handler, _uffd_faults)           \
{                                                                               \
        .name                   = SCAT4(uffd, _access, _with_af, #_mark_cmd),   \
        .guest_prepare          = { _PREPARE(_with_af),                         \
                                    _PREPARE(_access) },                        \
        .guest_test             = _access,                                      \
        .mem_mark_cmd           = _mark_cmd,                                    \
        .guest_test_check       = { _CHECK(_with_af) },                         \
        .uffd_data_handler      = _uffd_data_handler,                           \
        .uffd_pt_handler        = _uffd_pt_handler,                             \
        .expected_events        = { .uffd_faults = _uffd_faults, },             \
}

#define TEST_DIRTY_LOG(_access, _with_af, _test_check, _pt_check)               \
{                                                                               \
        .name                   = SCAT3(dirty_log, _access, _with_af),          \
        .data_memslot_flags     = KVM_MEM_LOG_DIRTY_PAGES,                      \
        .pt_memslot_flags       = KVM_MEM_LOG_DIRTY_PAGES,                      \
        .guest_prepare          = { _PREPARE(_with_af),                         \
                                    _PREPARE(_access) },                        \
        .guest_test             = _access,                                      \
        .guest_test_check       = { _CHECK(_with_af), _test_check, _pt_check }, \
        .expected_events        = { 0 },                                        \
}

#define TEST_UFFD_AND_DIRTY_LOG(_access, _with_af, _uffd_data_handler,          \
                                _uffd_faults, _test_check, _pt_check)           \
{                                                                               \
        .name                   = SCAT3(uffd_and_dirty_log, _access, _with_af), \
        .data_memslot_flags     = KVM_MEM_LOG_DIRTY_PAGES,                      \
        .pt_memslot_flags       = KVM_MEM_LOG_DIRTY_PAGES,                      \
        .guest_prepare          = { _PREPARE(_with_af),                         \
                                    _PREPARE(_access) },                        \
        .guest_test             = _access,                                      \
        .mem_mark_cmd           = CMD_HOLE_DATA | CMD_HOLE_PT,                  \
        .guest_test_check       = { _CHECK(_with_af), _test_check, _pt_check }, \
        .uffd_data_handler      = _uffd_data_handler,                           \
        .uffd_pt_handler        = uffd_pt_handler,                              \
        .expected_events        = { .uffd_faults = _uffd_faults, },             \
}

#define TEST_RO_MEMSLOT(_access, _mmio_handler, _mmio_exits)                    \
{                                                                               \
        .name                   = SCAT2(ro_memslot, _access),                   \
        .data_memslot_flags     = KVM_MEM_READONLY,                             \
        .pt_memslot_flags       = KVM_MEM_READONLY,                             \
        .guest_prepare          = { _PREPARE(_access) },                        \
        .guest_test             = _access,                                      \
        .mmio_handler           = _mmio_handler,                                \
        .expected_events        = { .mmio_exits = _mmio_exits },                \
}

#define TEST_RO_MEMSLOT_NO_SYNDROME(_access)                                    \
{                                                                               \
        .name                   = SCAT2(ro_memslot_no_syndrome, _access),       \
        .data_memslot_flags     = KVM_MEM_READONLY,                             \
        .pt_memslot_flags       = KVM_MEM_READONLY,                             \
        .guest_prepare          = { _PREPARE(_access) },                        \
        .guest_test             = _access,                                      \
        .fail_vcpu_run_handler  = fail_vcpu_run_mmio_no_syndrome_handler,       \
        .expected_events        = { .fail_vcpu_runs = 1 },                      \
}

#define TEST_RO_MEMSLOT_AND_DIRTY_LOG(_access, _mmio_handler, _mmio_exits,      \
                                      _test_check)                              \
{                                                                               \
        .name                   = SCAT2(ro_memslot, _access),                   \
        .data_memslot_flags     = KVM_MEM_READONLY | KVM_MEM_LOG_DIRTY_PAGES,   \
        .pt_memslot_flags       = KVM_MEM_READONLY | KVM_MEM_LOG_DIRTY_PAGES,   \
        .guest_prepare          = { _PREPARE(_access) },                        \
        .guest_test             = _access,                                      \
        .guest_test_check       = { _test_check },                              \
        .mmio_handler           = _mmio_handler,                                \
        .expected_events        = { .mmio_exits = _mmio_exits},                 \
}

#define TEST_RO_MEMSLOT_NO_SYNDROME_AND_DIRTY_LOG(_access, _test_check)         \
{                                                                               \
        .name                   = SCAT2(ro_memslot_no_syn_and_dlog, _access),   \
        .data_memslot_flags     = KVM_MEM_READONLY | KVM_MEM_LOG_DIRTY_PAGES,   \
        .pt_memslot_flags       = KVM_MEM_READONLY | KVM_MEM_LOG_DIRTY_PAGES,   \
        .guest_prepare          = { _PREPARE(_access) },                        \
        .guest_test             = _access,                                      \
        .guest_test_check       = { _test_check },                              \
        .fail_vcpu_run_handler  = fail_vcpu_run_mmio_no_syndrome_handler,       \
        .expected_events        = { .fail_vcpu_runs = 1 },                      \
}

#define TEST_RO_MEMSLOT_AND_UFFD(_access, _mmio_handler, _mmio_exits,           \
                                 _uffd_data_handler, _uffd_faults)              \
{                                                                               \
        .name                   = SCAT2(ro_memslot_uffd, _access),              \
        .data_memslot_flags     = KVM_MEM_READONLY,                             \
        .pt_memslot_flags       = KVM_MEM_READONLY,                             \
        .mem_mark_cmd           = CMD_HOLE_DATA | CMD_HOLE_PT,                  \
        .guest_prepare          = { _PREPARE(_access) },                        \
        .guest_test             = _access,                                      \
        .uffd_data_handler      = _uffd_data_handler,                           \
        .uffd_pt_handler        = uffd_pt_handler,                              \
        .mmio_handler           = _mmio_handler,                                \
        .expected_events        = { .mmio_exits = _mmio_exits,                  \
                                    .uffd_faults = _uffd_faults },              \
}

#define TEST_RO_MEMSLOT_NO_SYNDROME_AND_UFFD(_access, _uffd_data_handler,       \
                                             _uffd_faults)                      \
{                                                                               \
        .name                   = SCAT2(ro_memslot_no_syndrome, _access),       \
        .data_memslot_flags     = KVM_MEM_READONLY,                             \
        .pt_memslot_flags       = KVM_MEM_READONLY,                             \
        .mem_mark_cmd           = CMD_HOLE_DATA | CMD_HOLE_PT,                  \
        .guest_prepare          = { _PREPARE(_access) },                        \
        .guest_test             = _access,                                      \
        .uffd_data_handler      = _uffd_data_handler,                           \
        .uffd_pt_handler        = uffd_pt_handler,                      \
        .fail_vcpu_run_handler  = fail_vcpu_run_mmio_no_syndrome_handler,       \
        .expected_events        = { .fail_vcpu_runs = 1,                        \
                                    .uffd_faults = _uffd_faults },              \
}

static struct test_desc tests[] = {

        /* Check that HW is setting the Access Flag (AF) (sanity checks). */
        TEST_ACCESS(guest_read64, with_af, CMD_NONE),
        TEST_ACCESS(guest_ld_preidx, with_af, CMD_NONE),
        TEST_ACCESS(guest_cas, with_af, CMD_NONE),
        TEST_ACCESS(guest_write64, with_af, CMD_NONE),
        TEST_ACCESS(guest_st_preidx, with_af, CMD_NONE),
        TEST_ACCESS(guest_dc_zva, with_af, CMD_NONE),
        TEST_ACCESS(guest_exec, with_af, CMD_NONE),

        /*
         * Punch a hole in the data backing store, and then try multiple
         * accesses: reads should rturn zeroes, and writes should
         * re-populate the page. Moreover, the test also check that no
         * exception was generated in the guest.  Note that this
         * reading/writing behavior is the same as reading/writing a
         * punched page (with fallocate(FALLOC_FL_PUNCH_HOLE)) from
         * userspace.
         */
        TEST_ACCESS(guest_read64, no_af, CMD_HOLE_DATA),
        TEST_ACCESS(guest_cas, no_af, CMD_HOLE_DATA),
        TEST_ACCESS(guest_ld_preidx, no_af, CMD_HOLE_DATA),
        TEST_ACCESS(guest_write64, no_af, CMD_HOLE_DATA),
        TEST_ACCESS(guest_st_preidx, no_af, CMD_HOLE_DATA),
        TEST_ACCESS(guest_at, no_af, CMD_HOLE_DATA),
        TEST_ACCESS(guest_dc_zva, no_af, CMD_HOLE_DATA),

        /*
         * Punch holes in the data and PT backing stores and mark them for
         * userfaultfd handling. This should result in 2 faults: the access
         * on the data backing store, and its respective S1 page table walk
         * (S1PTW).
         */
        TEST_UFFD(guest_read64, with_af, CMD_HOLE_DATA | CMD_HOLE_PT,
                  uffd_data_handler, uffd_pt_handler, 2),
        TEST_UFFD(guest_read64, no_af, CMD_HOLE_DATA | CMD_HOLE_PT,
                  uffd_data_handler, uffd_pt_handler, 2),
        TEST_UFFD(guest_cas, with_af, CMD_HOLE_DATA | CMD_HOLE_PT,
                  uffd_data_handler, uffd_pt_handler, 2),
        /*
         * Can't test guest_at with_af as it's IMPDEF whether the AF is set.
         * The S1PTW fault should still be marked as a write.
         */
        TEST_UFFD(guest_at, no_af, CMD_HOLE_DATA | CMD_HOLE_PT,
                  uffd_no_handler, uffd_pt_handler, 1),
        TEST_UFFD(guest_ld_preidx, with_af, CMD_HOLE_DATA | CMD_HOLE_PT,
                  uffd_data_handler, uffd_pt_handler, 2),
        TEST_UFFD(guest_write64, with_af, CMD_HOLE_DATA | CMD_HOLE_PT,
                  uffd_data_handler, uffd_pt_handler, 2),
        TEST_UFFD(guest_dc_zva, with_af, CMD_HOLE_DATA | CMD_HOLE_PT,
                  uffd_data_handler, uffd_pt_handler, 2),
        TEST_UFFD(guest_st_preidx, with_af, CMD_HOLE_DATA | CMD_HOLE_PT,
                  uffd_data_handler, uffd_pt_handler, 2),
        TEST_UFFD(guest_exec, with_af, CMD_HOLE_DATA | CMD_HOLE_PT,
                  uffd_data_handler, uffd_pt_handler, 2),

        /*
         * Try accesses when the data and PT memory regions are both
         * tracked for dirty logging.
         */
        TEST_DIRTY_LOG(guest_read64, with_af, guest_check_no_write_in_dirty_log,
                       guest_check_s1ptw_wr_in_dirty_log),
        TEST_DIRTY_LOG(guest_read64, no_af, guest_check_no_write_in_dirty_log,
                       guest_check_no_s1ptw_wr_in_dirty_log),
        TEST_DIRTY_LOG(guest_ld_preidx, with_af,
                       guest_check_no_write_in_dirty_log,
                       guest_check_s1ptw_wr_in_dirty_log),
        TEST_DIRTY_LOG(guest_at, no_af, guest_check_no_write_in_dirty_log,
                       guest_check_no_s1ptw_wr_in_dirty_log),
        TEST_DIRTY_LOG(guest_exec, with_af, guest_check_no_write_in_dirty_log,
                       guest_check_s1ptw_wr_in_dirty_log),
        TEST_DIRTY_LOG(guest_write64, with_af, guest_check_write_in_dirty_log,
                       guest_check_s1ptw_wr_in_dirty_log),
        TEST_DIRTY_LOG(guest_cas, with_af, guest_check_write_in_dirty_log,
                       guest_check_s1ptw_wr_in_dirty_log),
        TEST_DIRTY_LOG(guest_dc_zva, with_af, guest_check_write_in_dirty_log,
                       guest_check_s1ptw_wr_in_dirty_log),
        TEST_DIRTY_LOG(guest_st_preidx, with_af, guest_check_write_in_dirty_log,
                       guest_check_s1ptw_wr_in_dirty_log),

        /*
         * Access when the data and PT memory regions are both marked for
         * dirty logging and UFFD at the same time. The expected result is
         * that writes should mark the dirty log and trigger a userfaultfd
         * write fault.  Reads/execs should result in a read userfaultfd
         * fault, and nothing in the dirty log.  Any S1PTW should result in
         * a write in the dirty log and a userfaultfd write.
         */
        TEST_UFFD_AND_DIRTY_LOG(guest_read64, with_af,
                                uffd_data_handler, 2,
                                guest_check_no_write_in_dirty_log,
                                guest_check_s1ptw_wr_in_dirty_log),
        TEST_UFFD_AND_DIRTY_LOG(guest_read64, no_af,
                                uffd_data_handler, 2,
                                guest_check_no_write_in_dirty_log,
                                guest_check_no_s1ptw_wr_in_dirty_log),
        TEST_UFFD_AND_DIRTY_LOG(guest_ld_preidx, with_af,
                                uffd_data_handler,
                                2, guest_check_no_write_in_dirty_log,
                                guest_check_s1ptw_wr_in_dirty_log),
        TEST_UFFD_AND_DIRTY_LOG(guest_at, with_af, uffd_no_handler, 1,
                                guest_check_no_write_in_dirty_log,
                                guest_check_s1ptw_wr_in_dirty_log),
        TEST_UFFD_AND_DIRTY_LOG(guest_exec, with_af,
                                uffd_data_handler, 2,
                                guest_check_no_write_in_dirty_log,
                                guest_check_s1ptw_wr_in_dirty_log),
        TEST_UFFD_AND_DIRTY_LOG(guest_write64, with_af,
                                uffd_data_handler,
                                2, guest_check_write_in_dirty_log,
                                guest_check_s1ptw_wr_in_dirty_log),
        TEST_UFFD_AND_DIRTY_LOG(guest_cas, with_af,
                                uffd_data_handler, 2,
                                guest_check_write_in_dirty_log,
                                guest_check_s1ptw_wr_in_dirty_log),
        TEST_UFFD_AND_DIRTY_LOG(guest_dc_zva, with_af,
                                uffd_data_handler,
                                2, guest_check_write_in_dirty_log,
                                guest_check_s1ptw_wr_in_dirty_log),
        TEST_UFFD_AND_DIRTY_LOG(guest_st_preidx, with_af,
                                uffd_data_handler, 2,
                                guest_check_write_in_dirty_log,
                                guest_check_s1ptw_wr_in_dirty_log),
        /*
         * Access when both the PT and data regions are marked read-only
         * (with KVM_MEM_READONLY). Writes with a syndrome result in an
         * MMIO exit, writes with no syndrome (e.g., CAS) result in a
         * failed vcpu run, and reads/execs with and without syndroms do
         * not fault.
         */
        TEST_RO_MEMSLOT(guest_read64, 0, 0),
        TEST_RO_MEMSLOT(guest_ld_preidx, 0, 0),
        TEST_RO_MEMSLOT(guest_at, 0, 0),
        TEST_RO_MEMSLOT(guest_exec, 0, 0),
        TEST_RO_MEMSLOT(guest_write64, mmio_on_test_gpa_handler, 1),
        TEST_RO_MEMSLOT_NO_SYNDROME(guest_dc_zva),
        TEST_RO_MEMSLOT_NO_SYNDROME(guest_cas),
        TEST_RO_MEMSLOT_NO_SYNDROME(guest_st_preidx),

        /*
         * The PT and data regions are both read-only and marked
         * for dirty logging at the same time. The expected result is that
         * for writes there should be no write in the dirty log. The
         * readonly handling is the same as if the memslot was not marked
         * for dirty logging: writes with a syndrome result in an MMIO
         * exit, and writes with no syndrome result in a failed vcpu run.
         */
        TEST_RO_MEMSLOT_AND_DIRTY_LOG(guest_read64, 0, 0,
                                      guest_check_no_write_in_dirty_log),
        TEST_RO_MEMSLOT_AND_DIRTY_LOG(guest_ld_preidx, 0, 0,
                                      guest_check_no_write_in_dirty_log),
        TEST_RO_MEMSLOT_AND_DIRTY_LOG(guest_at, 0, 0,
                                      guest_check_no_write_in_dirty_log),
        TEST_RO_MEMSLOT_AND_DIRTY_LOG(guest_exec, 0, 0,
                                      guest_check_no_write_in_dirty_log),
        TEST_RO_MEMSLOT_AND_DIRTY_LOG(guest_write64, mmio_on_test_gpa_handler,
                                      1, guest_check_no_write_in_dirty_log),
        TEST_RO_MEMSLOT_NO_SYNDROME_AND_DIRTY_LOG(guest_dc_zva,
                                                  guest_check_no_write_in_dirty_log),
        TEST_RO_MEMSLOT_NO_SYNDROME_AND_DIRTY_LOG(guest_cas,
                                                  guest_check_no_write_in_dirty_log),
        TEST_RO_MEMSLOT_NO_SYNDROME_AND_DIRTY_LOG(guest_st_preidx,
                                                  guest_check_no_write_in_dirty_log),

        /*
         * The PT and data regions are both read-only and punched with
         * holes tracked with userfaultfd.  The expected result is the
         * union of both userfaultfd and read-only behaviors. For example,
         * write accesses result in a userfaultfd write fault and an MMIO
         * exit.  Writes with no syndrome result in a failed vcpu run and
         * no userfaultfd write fault. Reads result in userfaultfd getting
         * triggered.
         */
        TEST_RO_MEMSLOT_AND_UFFD(guest_read64, 0, 0, uffd_data_handler, 2),
        TEST_RO_MEMSLOT_AND_UFFD(guest_ld_preidx, 0, 0, uffd_data_handler, 2),
        TEST_RO_MEMSLOT_AND_UFFD(guest_at, 0, 0, uffd_no_handler, 1),
        TEST_RO_MEMSLOT_AND_UFFD(guest_exec, 0, 0, uffd_data_handler, 2),
        TEST_RO_MEMSLOT_AND_UFFD(guest_write64, mmio_on_test_gpa_handler, 1,
                                 uffd_data_handler, 2),
        TEST_RO_MEMSLOT_NO_SYNDROME_AND_UFFD(guest_cas, uffd_data_handler, 2),
        TEST_RO_MEMSLOT_NO_SYNDROME_AND_UFFD(guest_dc_zva, uffd_no_handler, 1),
        TEST_RO_MEMSLOT_NO_SYNDROME_AND_UFFD(guest_st_preidx, uffd_no_handler, 1),

        { 0 }
};

static void for_each_test_and_guest_mode(enum vm_mem_backing_src_type src_type)
{
        struct test_desc *t;

        for (t = &tests[0]; t->name; t++) {
                if (t->skip)
                        continue;

                struct test_params p = {
                        .src_type = src_type,
                        .test_desc = t,
                };

                for_each_guest_mode(run_test, &p);
        }
}

int main(int argc, char *argv[])
{
        enum vm_mem_backing_src_type src_type;
        int opt;

        src_type = DEFAULT_VM_MEM_SRC;

        while ((opt = getopt(argc, argv, "hm:s:")) != -1) {
                switch (opt) {
                case 'm':
                        guest_modes_cmdline(optarg);
                        break;
                case 's':
                        src_type = parse_backing_src_type(optarg);
                        break;
                case 'h':
                default:
                        help(argv[0]);
                        exit(0);
                }
        }

        for_each_test_and_guest_mode(src_type);
        return 0;
}