/*
 * tools/testing/selftests/kvm/lib/kvm_util.c
 *
 * Copyright (C) 2018, Google LLC.
 *
 * This work is licensed under the terms of the GNU GPL, version 2.
 */

#include "test_util.h"
#include "kvm_util.h"
#include "kvm_util_internal.h"

#include <assert.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <linux/kernel.h>

#define KVM_UTIL_PGS_PER_HUGEPG 512
#define KVM_UTIL_MIN_PFN        2

/* Aligns x up to the next multiple of size. Size must be a power of 2. */
static void *align(void *x, size_t size)
{
        size_t mask = size - 1;
        TEST_ASSERT(size != 0 && !(size & (size - 1)),
                    "size not a power of 2: %lu", size);
        return (void *) (((size_t) x + mask) & ~mask);
}

/*
 * Capability
 *
 * Input Args:
 *   cap - Capability
 *
 * Output Args: None
 *
 * Return:
 *   On success, the Value corresponding to the capability (KVM_CAP_*)
 *   specified by the value of cap.  On failure a TEST_ASSERT failure
 *   is produced.
 *
 * Looks up and returns the value corresponding to the capability
 * (KVM_CAP_*) given by cap.
 */
int kvm_check_cap(long cap)
{
        int ret;
        int kvm_fd;

        kvm_fd = open(KVM_DEV_PATH, O_RDONLY);
        if (kvm_fd < 0)
                exit(KSFT_SKIP);

        ret = ioctl(kvm_fd, KVM_CHECK_EXTENSION, cap);
        TEST_ASSERT(ret != -1, "KVM_CHECK_EXTENSION IOCTL failed,\n"
                "  rc: %i errno: %i", ret, errno);

        close(kvm_fd);

        return ret;
}

/* VM Enable Capability
 *
 * Input Args:
 *   vm - Virtual Machine
 *   cap - Capability
 *
 * Output Args: None
 *
 * Return: On success, 0. On failure a TEST_ASSERT failure is produced.
 *
 * Enables a capability (KVM_CAP_*) on the VM.
 */
int vm_enable_cap(struct kvm_vm *vm, struct kvm_enable_cap *cap)
{
        int ret;

        ret = ioctl(vm->fd, KVM_ENABLE_CAP, cap);
        TEST_ASSERT(ret == 0, "KVM_ENABLE_CAP IOCTL failed,\n"
                "  rc: %i errno: %i", ret, errno);

        return ret;
}

static void vm_open(struct kvm_vm *vm, int perm, unsigned long type)
{
        vm->kvm_fd = open(KVM_DEV_PATH, perm);
        if (vm->kvm_fd < 0)
                exit(KSFT_SKIP);

        if (!kvm_check_cap(KVM_CAP_IMMEDIATE_EXIT)) {
                fprintf(stderr, "immediate_exit not available, skipping test\n");
                exit(KSFT_SKIP);
        }

        vm->fd = ioctl(vm->kvm_fd, KVM_CREATE_VM, type);
        TEST_ASSERT(vm->fd >= 0, "KVM_CREATE_VM ioctl failed, "
                "rc: %i errno: %i", vm->fd, errno);
}

const char * const vm_guest_mode_string[] = {
        "PA-bits:52, VA-bits:48, 4K pages",
        "PA-bits:52, VA-bits:48, 64K pages",
        "PA-bits:48, VA-bits:48, 4K pages",
        "PA-bits:48, VA-bits:48, 64K pages",
        "PA-bits:40, VA-bits:48, 4K pages",
        "PA-bits:40, VA-bits:48, 64K pages",
};
_Static_assert(sizeof(vm_guest_mode_string)/sizeof(char *) == NUM_VM_MODES,
               "Missing new mode strings?");

/*
 * VM Create
 *
 * Input Args:
 *   mode - VM Mode (e.g. VM_MODE_P52V48_4K)
 *   phy_pages - Physical memory pages
 *   perm - permission
 *
 * Output Args: None
 *
 * Return:
 *   Pointer to opaque structure that describes the created VM.
 *
 * Creates a VM with the mode specified by mode (e.g. VM_MODE_P52V48_4K).
 * When phy_pages is non-zero, a memory region of phy_pages physical pages
 * is created and mapped starting at guest physical address 0.  The file
 * descriptor to control the created VM is created with the permissions
 * given by perm (e.g. O_RDWR).
 */
struct kvm_vm *_vm_create(enum vm_guest_mode mode, uint64_t phy_pages,
                          int perm, unsigned long type)
{
        struct kvm_vm *vm;
        int kvm_fd;

        vm = calloc(1, sizeof(*vm));
        TEST_ASSERT(vm != NULL, "Insufficient Memory");

        vm->mode = mode;
        vm->type = type;
        vm_open(vm, perm, type);

        /* Setup mode specific traits. */
        switch (vm->mode) {
        case VM_MODE_P52V48_4K:
                vm->pgtable_levels = 4;
                vm->pa_bits = 52;
                vm->va_bits = 48;
                vm->page_size = 0x1000;
                vm->page_shift = 12;
                break;
        case VM_MODE_P52V48_64K:
                vm->pgtable_levels = 3;
                vm->pa_bits = 52;
                vm->va_bits = 48;
                vm->page_size = 0x10000;
                vm->page_shift = 16;
                break;
        case VM_MODE_P48V48_4K:
                vm->pgtable_levels = 4;
                vm->pa_bits = 48;
                vm->va_bits = 48;
                vm->page_size = 0x1000;
                vm->page_shift = 12;
                break;
        case VM_MODE_P48V48_64K:
                vm->pgtable_levels = 3;
                vm->pa_bits = 48;
                vm->va_bits = 48;
                vm->page_size = 0x10000;
                vm->page_shift = 16;
                break;
        case VM_MODE_P40V48_4K:
                vm->pgtable_levels = 4;
                vm->pa_bits = 40;
                vm->va_bits = 48;
                vm->page_size = 0x1000;
                vm->page_shift = 12;
                break;
        case VM_MODE_P40V48_64K:
                vm->pgtable_levels = 3;
                vm->pa_bits = 40;
                vm->va_bits = 48;
                vm->page_size = 0x10000;
                vm->page_shift = 16;
                break;
        default:
                TEST_ASSERT(false, "Unknown guest mode, mode: 0x%x", mode);
        }

        /* Limit to VA-bit canonical virtual addresses. */
        vm->vpages_valid = sparsebit_alloc();
        sparsebit_set_num(vm->vpages_valid,
                0, (1ULL << (vm->va_bits - 1)) >> vm->page_shift);
        sparsebit_set_num(vm->vpages_valid,
                (~((1ULL << (vm->va_bits - 1)) - 1)) >> vm->page_shift,
                (1ULL << (vm->va_bits - 1)) >> vm->page_shift);

        /* Limit physical addresses to PA-bits. */
        vm->max_gfn = ((1ULL << vm->pa_bits) >> vm->page_shift) - 1;

        /* Allocate and setup memory for guest. */
        vm->vpages_mapped = sparsebit_alloc();
        if (phy_pages != 0)
                vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
                                            0, 0, phy_pages, 0);

        return vm;
}

struct kvm_vm *vm_create(enum vm_guest_mode mode, uint64_t phy_pages, int perm)
{
        return _vm_create(mode, phy_pages, perm, 0);
}

/*
 * VM Restart
 *
 * Input Args:
 *   vm - VM that has been released before
 *   perm - permission
 *
 * Output Args: None
 *
 * Reopens the file descriptors associated to the VM and reinstates the
 * global state, such as the irqchip and the memory regions that are mapped
 * into the guest.
 */
void kvm_vm_restart(struct kvm_vm *vmp, int perm)
{
        struct userspace_mem_region *region;

        vm_open(vmp, perm, vmp->type);
        if (vmp->has_irqchip)
                vm_create_irqchip(vmp);

        for (region = vmp->userspace_mem_region_head; region;
                region = region->next) {
                int ret = ioctl(vmp->fd, KVM_SET_USER_MEMORY_REGION, &region->region);
                TEST_ASSERT(ret == 0, "KVM_SET_USER_MEMORY_REGION IOCTL failed,\n"
                            "  rc: %i errno: %i\n"
                            "  slot: %u flags: 0x%x\n"
                            "  guest_phys_addr: 0x%lx size: 0x%lx",
                            ret, errno, region->region.slot,
                            region->region.flags,
                            region->region.guest_phys_addr,
                            region->region.memory_size);
        }
}

void kvm_vm_get_dirty_log(struct kvm_vm *vm, int slot, void *log)
{
        struct kvm_dirty_log args = { .dirty_bitmap = log, .slot = slot };
        int ret;

        ret = ioctl(vm->fd, KVM_GET_DIRTY_LOG, &args);
        TEST_ASSERT(ret == 0, "%s: KVM_GET_DIRTY_LOG failed: %s",
                    strerror(-ret));
}

void kvm_vm_clear_dirty_log(struct kvm_vm *vm, int slot, void *log,
                            uint64_t first_page, uint32_t num_pages)
{
        struct kvm_clear_dirty_log args = { .dirty_bitmap = log, .slot = slot,
                                            .first_page = first_page,
                                            .num_pages = num_pages };
        int ret;

        ret = ioctl(vm->fd, KVM_CLEAR_DIRTY_LOG, &args);
        TEST_ASSERT(ret == 0, "%s: KVM_CLEAR_DIRTY_LOG failed: %s",
                    strerror(-ret));
}

/*
 * Userspace Memory Region Find
 *
 * Input Args:
 *   vm - Virtual Machine
 *   start - Starting VM physical address
 *   end - Ending VM physical address, inclusive.
 *
 * Output Args: None
 *
 * Return:
 *   Pointer to overlapping region, NULL if no such region.
 *
 * Searches for a region with any physical memory that overlaps with
 * any portion of the guest physical addresses from start to end
 * inclusive.  If multiple overlapping regions exist, a pointer to any
 * of the regions is returned.  Null is returned only when no overlapping
 * region exists.
 */
static struct userspace_mem_region *
userspace_mem_region_find(struct kvm_vm *vm, uint64_t start, uint64_t end)
{
        struct userspace_mem_region *region;

        for (region = vm->userspace_mem_region_head; region;
                region = region->next) {
                uint64_t existing_start = region->region.guest_phys_addr;
                uint64_t existing_end = region->region.guest_phys_addr
                        + region->region.memory_size - 1;
                if (start <= existing_end && end >= existing_start)
                        return region;
        }

        return NULL;
}

/*
 * KVM Userspace Memory Region Find
 *
 * Input Args:
 *   vm - Virtual Machine
 *   start - Starting VM physical address
 *   end - Ending VM physical address, inclusive.
 *
 * Output Args: None
 *
 * Return:
 *   Pointer to overlapping region, NULL if no such region.
 *
 * Public interface to userspace_mem_region_find. Allows tests to look up
 * the memslot datastructure for a given range of guest physical memory.
 */
struct kvm_userspace_memory_region *
kvm_userspace_memory_region_find(struct kvm_vm *vm, uint64_t start,
                                 uint64_t end)
{
        struct userspace_mem_region *region;

        region = userspace_mem_region_find(vm, start, end);
        if (!region)
                return NULL;

        return &region->region;
}

/*
 * VCPU Find
 *
 * Input Args:
 *   vm - Virtual Machine
 *   vcpuid - VCPU ID
 *
 * Output Args: None
 *
 * Return:
 *   Pointer to VCPU structure
 *
 * Locates a vcpu structure that describes the VCPU specified by vcpuid and
 * returns a pointer to it.  Returns NULL if the VM doesn't contain a VCPU
 * for the specified vcpuid.
 */
struct vcpu *vcpu_find(struct kvm_vm *vm, uint32_t vcpuid)
{
        struct vcpu *vcpup;

        for (vcpup = vm->vcpu_head; vcpup; vcpup = vcpup->next) {
                if (vcpup->id == vcpuid)
                        return vcpup;
        }

        return NULL;
}

/*
 * VM VCPU Remove
 *
 * Input Args:
 *   vm - Virtual Machine
 *   vcpuid - VCPU ID
 *
 * Output Args: None
 *
 * Return: None, TEST_ASSERT failures for all error conditions
 *
 * Within the VM specified by vm, removes the VCPU given by vcpuid.
 */
static void vm_vcpu_rm(struct kvm_vm *vm, uint32_t vcpuid)
{
        struct vcpu *vcpu = vcpu_find(vm, vcpuid);
        int ret;

        ret = munmap(vcpu->state, sizeof(*vcpu->state));
        TEST_ASSERT(ret == 0, "munmap of VCPU fd failed, rc: %i "
                "errno: %i", ret, errno);
        close(vcpu->fd);
        TEST_ASSERT(ret == 0, "Close of VCPU fd failed, rc: %i "
                "errno: %i", ret, errno);

        if (vcpu->next)
                vcpu->next->prev = vcpu->prev;
        if (vcpu->prev)
                vcpu->prev->next = vcpu->next;
        else
                vm->vcpu_head = vcpu->next;
        free(vcpu);
}

void kvm_vm_release(struct kvm_vm *vmp)
{
        int ret;

        while (vmp->vcpu_head)
                vm_vcpu_rm(vmp, vmp->vcpu_head->id);

        ret = close(vmp->fd);
        TEST_ASSERT(ret == 0, "Close of vm fd failed,\n"
                "  vmp->fd: %i rc: %i errno: %i", vmp->fd, ret, errno);

        close(vmp->kvm_fd);
        TEST_ASSERT(ret == 0, "Close of /dev/kvm fd failed,\n"
                "  vmp->kvm_fd: %i rc: %i errno: %i", vmp->kvm_fd, ret, errno);
}

/*
 * Destroys and frees the VM pointed to by vmp.
 */
void kvm_vm_free(struct kvm_vm *vmp)
{
        int ret;

        if (vmp == NULL)
                return;

        /* Free userspace_mem_regions. */
        while (vmp->userspace_mem_region_head) {
                struct userspace_mem_region *region
                        = vmp->userspace_mem_region_head;

                region->region.memory_size = 0;
                ret = ioctl(vmp->fd, KVM_SET_USER_MEMORY_REGION,
                        &region->region);
                TEST_ASSERT(ret == 0, "KVM_SET_USER_MEMORY_REGION IOCTL failed, "
                        "rc: %i errno: %i", ret, errno);

                vmp->userspace_mem_region_head = region->next;
                sparsebit_free(&region->unused_phy_pages);
                ret = munmap(region->mmap_start, region->mmap_size);
                TEST_ASSERT(ret == 0, "munmap failed, rc: %i errno: %i",
                            ret, errno);

                free(region);
        }

        /* Free sparsebit arrays. */
        sparsebit_free(&vmp->vpages_valid);
        sparsebit_free(&vmp->vpages_mapped);

        kvm_vm_release(vmp);

        /* Free the structure describing the VM. */
        free(vmp);
}

/*
 * Memory Compare, host virtual to guest virtual
 *
 * Input Args:
 *   hva - Starting host virtual address
 *   vm - Virtual Machine
 *   gva - Starting guest virtual address
 *   len - number of bytes to compare
 *
 * Output Args: None
 *
 * Input/Output Args: None
 *
 * Return:
 *   Returns 0 if the bytes starting at hva for a length of len
 *   are equal the guest virtual bytes starting at gva.  Returns
 *   a value < 0, if bytes at hva are less than those at gva.
 *   Otherwise a value > 0 is returned.
 *
 * Compares the bytes starting at the host virtual address hva, for
 * a length of len, to the guest bytes starting at the guest virtual
 * address given by gva.
 */
int kvm_memcmp_hva_gva(void *hva, struct kvm_vm *vm, vm_vaddr_t gva, size_t len)
{
        size_t amt;

        /*
         * Compare a batch of bytes until either a match is found
         * or all the bytes have been compared.
         */
        for (uintptr_t offset = 0; offset < len; offset += amt) {
                uintptr_t ptr1 = (uintptr_t)hva + offset;

                /*
                 * Determine host address for guest virtual address
                 * at offset.
                 */
                uintptr_t ptr2 = (uintptr_t)addr_gva2hva(vm, gva + offset);

                /*
                 * Determine amount to compare on this pass.
                 * Don't allow the comparsion to cross a page boundary.
                 */
                amt = len - offset;
                if ((ptr1 >> vm->page_shift) != ((ptr1 + amt) >> vm->page_shift))
                        amt = vm->page_size - (ptr1 % vm->page_size);
                if ((ptr2 >> vm->page_shift) != ((ptr2 + amt) >> vm->page_shift))
                        amt = vm->page_size - (ptr2 % vm->page_size);

                assert((ptr1 >> vm->page_shift) == ((ptr1 + amt - 1) >> vm->page_shift));
                assert((ptr2 >> vm->page_shift) == ((ptr2 + amt - 1) >> vm->page_shift));

                /*
                 * Perform the comparison.  If there is a difference
                 * return that result to the caller, otherwise need
                 * to continue on looking for a mismatch.
                 */
                int ret = memcmp((void *)ptr1, (void *)ptr2, amt);
                if (ret != 0)
                        return ret;
        }

        /*
         * No mismatch found.  Let the caller know the two memory
         * areas are equal.
         */
        return 0;
}

/*
 * VM Userspace Memory Region Add
 *
 * Input Args:
 *   vm - Virtual Machine
 *   backing_src - Storage source for this region.
 *                 NULL to use anonymous memory.
 *   guest_paddr - Starting guest physical address
 *   slot - KVM region slot
 *   npages - Number of physical pages
 *   flags - KVM memory region flags (e.g. KVM_MEM_LOG_DIRTY_PAGES)
 *
 * Output Args: None
 *
 * Return: None
 *
 * Allocates a memory area of the number of pages specified by npages
 * and maps it to the VM specified by vm, at a starting physical address
 * given by guest_paddr.  The region is created with a KVM region slot
 * given by slot, which must be unique and < KVM_MEM_SLOTS_NUM.  The
 * region is created with the flags given by flags.
 */
void vm_userspace_mem_region_add(struct kvm_vm *vm,
        enum vm_mem_backing_src_type src_type,
        uint64_t guest_paddr, uint32_t slot, uint64_t npages,
        uint32_t flags)
{
        int ret;
        unsigned long pmem_size = 0;
        struct userspace_mem_region *region;
        size_t huge_page_size = KVM_UTIL_PGS_PER_HUGEPG * vm->page_size;

        TEST_ASSERT((guest_paddr % vm->page_size) == 0, "Guest physical "
                "address not on a page boundary.\n"
                "  guest_paddr: 0x%lx vm->page_size: 0x%x",
                guest_paddr, vm->page_size);
        TEST_ASSERT((((guest_paddr >> vm->page_shift) + npages) - 1)
                <= vm->max_gfn, "Physical range beyond maximum "
                "supported physical address,\n"
                "  guest_paddr: 0x%lx npages: 0x%lx\n"
                "  vm->max_gfn: 0x%lx vm->page_size: 0x%x",
                guest_paddr, npages, vm->max_gfn, vm->page_size);

        /*
         * Confirm a mem region with an overlapping address doesn't
         * already exist.
         */
        region = (struct userspace_mem_region *) userspace_mem_region_find(
                vm, guest_paddr, (guest_paddr + npages * vm->page_size) - 1);
        if (region != NULL)
                TEST_ASSERT(false, "overlapping userspace_mem_region already "
                        "exists\n"
                        "  requested guest_paddr: 0x%lx npages: 0x%lx "
                        "page_size: 0x%x\n"
                        "  existing guest_paddr: 0x%lx size: 0x%lx",
                        guest_paddr, npages, vm->page_size,
                        (uint64_t) region->region.guest_phys_addr,
                        (uint64_t) region->region.memory_size);

        /* Confirm no region with the requested slot already exists. */
        for (region = vm->userspace_mem_region_head; region;
                region = region->next) {
                if (region->region.slot == slot)
                        break;
        }
        if (region != NULL)
                TEST_ASSERT(false, "A mem region with the requested slot "
                        "already exists.\n"
                        "  requested slot: %u paddr: 0x%lx npages: 0x%lx\n"
                        "  existing slot: %u paddr: 0x%lx size: 0x%lx",
                        slot, guest_paddr, npages,
                        region->region.slot,
                        (uint64_t) region->region.guest_phys_addr,
                        (uint64_t) region->region.memory_size);

        /* Allocate and initialize new mem region structure. */
        region = calloc(1, sizeof(*region));
        TEST_ASSERT(region != NULL, "Insufficient Memory");
        region->mmap_size = npages * vm->page_size;

        /* Enough memory to align up to a huge page. */
        if (src_type == VM_MEM_SRC_ANONYMOUS_THP)
                region->mmap_size += huge_page_size;
        region->mmap_start = mmap(NULL, region->mmap_size,
                                  PROT_READ | PROT_WRITE,
                                  MAP_PRIVATE | MAP_ANONYMOUS
                                  | (src_type == VM_MEM_SRC_ANONYMOUS_HUGETLB ? MAP_HUGETLB : 0),
                                  -1, 0);
        TEST_ASSERT(region->mmap_start != MAP_FAILED,
                    "test_malloc failed, mmap_start: %p errno: %i",
                    region->mmap_start, errno);

        /* Align THP allocation up to start of a huge page. */
        region->host_mem = align(region->mmap_start,
                                 src_type == VM_MEM_SRC_ANONYMOUS_THP ?  huge_page_size : 1);

        /* As needed perform madvise */
        if (src_type == VM_MEM_SRC_ANONYMOUS || src_type == VM_MEM_SRC_ANONYMOUS_THP) {
                ret = madvise(region->host_mem, npages * vm->page_size,
                             src_type == VM_MEM_SRC_ANONYMOUS ? MADV_NOHUGEPAGE : MADV_HUGEPAGE);
                TEST_ASSERT(ret == 0, "madvise failed,\n"
                            "  addr: %p\n"
                            "  length: 0x%lx\n"
                            "  src_type: %x",
                            region->host_mem, npages * vm->page_size, src_type);
        }

        region->unused_phy_pages = sparsebit_alloc();
        sparsebit_set_num(region->unused_phy_pages,
                guest_paddr >> vm->page_shift, npages);
        region->region.slot = slot;
        region->region.flags = flags;
        region->region.guest_phys_addr = guest_paddr;
        region->region.memory_size = npages * vm->page_size;
        region->region.userspace_addr = (uintptr_t) region->host_mem;
        ret = ioctl(vm->fd, KVM_SET_USER_MEMORY_REGION, &region->region);
        TEST_ASSERT(ret == 0, "KVM_SET_USER_MEMORY_REGION IOCTL failed,\n"
                "  rc: %i errno: %i\n"
                "  slot: %u flags: 0x%x\n"
                "  guest_phys_addr: 0x%lx size: 0x%lx",
                ret, errno, slot, flags,
                guest_paddr, (uint64_t) region->region.memory_size);

        /* Add to linked-list of memory regions. */
        if (vm->userspace_mem_region_head)
                vm->userspace_mem_region_head->prev = region;
        region->next = vm->userspace_mem_region_head;
        vm->userspace_mem_region_head = region;
}

/*
 * Memslot to region
 *
 * Input Args:
 *   vm - Virtual Machine
 *   memslot - KVM memory slot ID
 *
 * Output Args: None
 *
 * Return:
 *   Pointer to memory region structure that describe memory region
 *   using kvm memory slot ID given by memslot.  TEST_ASSERT failure
 *   on error (e.g. currently no memory region using memslot as a KVM
 *   memory slot ID).
 */
static struct userspace_mem_region *
memslot2region(struct kvm_vm *vm, uint32_t memslot)
{
        struct userspace_mem_region *region;

        for (region = vm->userspace_mem_region_head; region;
                region = region->next) {
                if (region->region.slot == memslot)
                        break;
        }
        if (region == NULL) {
                fprintf(stderr, "No mem region with the requested slot found,\n"
                        "  requested slot: %u\n", memslot);
                fputs("---- vm dump ----\n", stderr);
                vm_dump(stderr, vm, 2);
                TEST_ASSERT(false, "Mem region not found");
        }

        return region;
}

/*
 * VM Memory Region Flags Set
 *
 * Input Args:
 *   vm - Virtual Machine
 *   flags - Starting guest physical address
 *
 * Output Args: None
 *
 * Return: None
 *
 * Sets the flags of the memory region specified by the value of slot,
 * to the values given by flags.
 */
void vm_mem_region_set_flags(struct kvm_vm *vm, uint32_t slot, uint32_t flags)
{
        int ret;
        struct userspace_mem_region *region;

        region = memslot2region(vm, slot);

        region->region.flags = flags;

        ret = ioctl(vm->fd, KVM_SET_USER_MEMORY_REGION, &region->region);

        TEST_ASSERT(ret == 0, "KVM_SET_USER_MEMORY_REGION IOCTL failed,\n"
                "  rc: %i errno: %i slot: %u flags: 0x%x",
                ret, errno, slot, flags);
}

/*
 * VCPU mmap Size
 *
 * Input Args: None
 *
 * Output Args: None
 *
 * Return:
 *   Size of VCPU state
 *
 * Returns the size of the structure pointed to by the return value
 * of vcpu_state().
 */
static int vcpu_mmap_sz(void)
{
        int dev_fd, ret;

        dev_fd = open(KVM_DEV_PATH, O_RDONLY);
        if (dev_fd < 0)
                exit(KSFT_SKIP);

        ret = ioctl(dev_fd, KVM_GET_VCPU_MMAP_SIZE, NULL);
        TEST_ASSERT(ret >= sizeof(struct kvm_run),
                "%s KVM_GET_VCPU_MMAP_SIZE ioctl failed, rc: %i errno: %i",
                __func__, ret, errno);

        close(dev_fd);

        return ret;
}

/*
 * VM VCPU Add
 *
 * Input Args:
 *   vm - Virtual Machine
 *   vcpuid - VCPU ID
 *
 * Output Args: None
 *
 * Return: None
 *
 * Creates and adds to the VM specified by vm and virtual CPU with
 * the ID given by vcpuid.
 */
void vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpuid, int pgd_memslot,
                 int gdt_memslot)
{
        struct vcpu *vcpu;

        /* Confirm a vcpu with the specified id doesn't already exist. */
        vcpu = vcpu_find(vm, vcpuid);
        if (vcpu != NULL)
                TEST_ASSERT(false, "vcpu with the specified id "
                        "already exists,\n"
                        "  requested vcpuid: %u\n"
                        "  existing vcpuid: %u state: %p",
                        vcpuid, vcpu->id, vcpu->state);

        /* Allocate and initialize new vcpu structure. */
        vcpu = calloc(1, sizeof(*vcpu));
        TEST_ASSERT(vcpu != NULL, "Insufficient Memory");
        vcpu->id = vcpuid;
        vcpu->fd = ioctl(vm->fd, KVM_CREATE_VCPU, vcpuid);
        TEST_ASSERT(vcpu->fd >= 0, "KVM_CREATE_VCPU failed, rc: %i errno: %i",
                vcpu->fd, errno);

        TEST_ASSERT(vcpu_mmap_sz() >= sizeof(*vcpu->state), "vcpu mmap size "
                "smaller than expected, vcpu_mmap_sz: %i expected_min: %zi",
                vcpu_mmap_sz(), sizeof(*vcpu->state));
        vcpu->state = (struct kvm_run *) mmap(NULL, sizeof(*vcpu->state),
                PROT_READ | PROT_WRITE, MAP_SHARED, vcpu->fd, 0);
        TEST_ASSERT(vcpu->state != MAP_FAILED, "mmap vcpu_state failed, "
                "vcpu id: %u errno: %i", vcpuid, errno);

        /* Add to linked-list of VCPUs. */
        if (vm->vcpu_head)
                vm->vcpu_head->prev = vcpu;
        vcpu->next = vm->vcpu_head;
        vm->vcpu_head = vcpu;

        vcpu_setup(vm, vcpuid, pgd_memslot, gdt_memslot);
}

/*
 * VM Virtual Address Unused Gap
 *
 * Input Args:
 *   vm - Virtual Machine
 *   sz - Size (bytes)
 *   vaddr_min - Minimum Virtual Address
 *
 * Output Args: None
 *
 * Return:
 *   Lowest virtual address at or below vaddr_min, with at least
 *   sz unused bytes.  TEST_ASSERT failure if no area of at least
 *   size sz is available.
 *
 * Within the VM specified by vm, locates the lowest starting virtual
 * address >= vaddr_min, that has at least sz unallocated bytes.  A
 * TEST_ASSERT failure occurs for invalid input or no area of at least
 * sz unallocated bytes >= vaddr_min is available.
 */
static vm_vaddr_t vm_vaddr_unused_gap(struct kvm_vm *vm, size_t sz,
                                      vm_vaddr_t vaddr_min)
{
        uint64_t pages = (sz + vm->page_size - 1) >> vm->page_shift;

        /* Determine lowest permitted virtual page index. */
        uint64_t pgidx_start = (vaddr_min + vm->page_size - 1) >> vm->page_shift;
        if ((pgidx_start * vm->page_size) < vaddr_min)
                goto no_va_found;

        /* Loop over section with enough valid virtual page indexes. */
        if (!sparsebit_is_set_num(vm->vpages_valid,
                pgidx_start, pages))
                pgidx_start = sparsebit_next_set_num(vm->vpages_valid,
                        pgidx_start, pages);
        do {
                /*
                 * Are there enough unused virtual pages available at
                 * the currently proposed starting virtual page index.
                 * If not, adjust proposed starting index to next
                 * possible.
                 */
                if (sparsebit_is_clear_num(vm->vpages_mapped,
                        pgidx_start, pages))
                        goto va_found;
                pgidx_start = sparsebit_next_clear_num(vm->vpages_mapped,
                        pgidx_start, pages);
                if (pgidx_start == 0)
                        goto no_va_found;

                /*
                 * If needed, adjust proposed starting virtual address,
                 * to next range of valid virtual addresses.
                 */
                if (!sparsebit_is_set_num(vm->vpages_valid,
                        pgidx_start, pages)) {
                        pgidx_start = sparsebit_next_set_num(
                                vm->vpages_valid, pgidx_start, pages);
                        if (pgidx_start == 0)
                                goto no_va_found;
                }
        } while (pgidx_start != 0);

no_va_found:
        TEST_ASSERT(false, "No vaddr of specified pages available, "
                "pages: 0x%lx", pages);

        /* NOT REACHED */
        return -1;

va_found:
        TEST_ASSERT(sparsebit_is_set_num(vm->vpages_valid,
                pgidx_start, pages),
                "Unexpected, invalid virtual page index range,\n"
                "  pgidx_start: 0x%lx\n"
                "  pages: 0x%lx",
                pgidx_start, pages);
        TEST_ASSERT(sparsebit_is_clear_num(vm->vpages_mapped,
                pgidx_start, pages),
                "Unexpected, pages already mapped,\n"
                "  pgidx_start: 0x%lx\n"
                "  pages: 0x%lx",
                pgidx_start, pages);

        return pgidx_start * vm->page_size;
}

/*
 * VM Virtual Address Allocate
 *
 * Input Args:
 *   vm - Virtual Machine
 *   sz - Size in bytes
 *   vaddr_min - Minimum starting virtual address
 *   data_memslot - Memory region slot for data pages
 *   pgd_memslot - Memory region slot for new virtual translation tables
 *
 * Output Args: None
 *
 * Return:
 *   Starting guest virtual address
 *
 * Allocates at least sz bytes within the virtual address space of the vm
 * given by vm.  The allocated bytes are mapped to a virtual address >=
 * the address given by vaddr_min.  Note that each allocation uses a
 * a unique set of pages, with the minimum real allocation being at least
 * a page.
 */
vm_vaddr_t vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min,
                          uint32_t data_memslot, uint32_t pgd_memslot)
{
        uint64_t pages = (sz >> vm->page_shift) + ((sz % vm->page_size) != 0);

        virt_pgd_alloc(vm, pgd_memslot);

        /*
         * Find an unused range of virtual page addresses of at least
         * pages in length.
         */
        vm_vaddr_t vaddr_start = vm_vaddr_unused_gap(vm, sz, vaddr_min);

        /* Map the virtual pages. */
        for (vm_vaddr_t vaddr = vaddr_start; pages > 0;
                pages--, vaddr += vm->page_size) {
                vm_paddr_t paddr;

                paddr = vm_phy_page_alloc(vm,
                                KVM_UTIL_MIN_PFN * vm->page_size, data_memslot);

                virt_pg_map(vm, vaddr, paddr, pgd_memslot);

                sparsebit_set(vm->vpages_mapped,
                        vaddr >> vm->page_shift);
        }

        return vaddr_start;
}

/*
 * Map a range of VM virtual address to the VM's physical address
 *
 * Input Args:
 *   vm - Virtual Machine
 *   vaddr - Virtuall address to map
 *   paddr - VM Physical Address
 *   size - The size of the range to map
 *   pgd_memslot - Memory region slot for new virtual translation tables
 *
 * Output Args: None
 *
 * Return: None
 *
 * Within the VM given by vm, creates a virtual translation for the
 * page range starting at vaddr to the page range starting at paddr.
 */
void virt_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
              size_t size, uint32_t pgd_memslot)
{
        size_t page_size = vm->page_size;
        size_t npages = size / page_size;

        TEST_ASSERT(vaddr + size > vaddr, "Vaddr overflow");
        TEST_ASSERT(paddr + size > paddr, "Paddr overflow");

        while (npages--) {
                virt_pg_map(vm, vaddr, paddr, pgd_memslot);
                vaddr += page_size;
                paddr += page_size;
        }
}

/*
 * Address VM Physical to Host Virtual
 *
 * Input Args:
 *   vm - Virtual Machine
 *   gpa - VM physical address
 *
 * Output Args: None
 *
 * Return:
 *   Equivalent host virtual address
 *
 * Locates the memory region containing the VM physical address given
 * by gpa, within the VM given by vm.  When found, the host virtual
 * address providing the memory to the vm physical address is returned.
 * A TEST_ASSERT failure occurs if no region containing gpa exists.
 */
void *addr_gpa2hva(struct kvm_vm *vm, vm_paddr_t gpa)
{

        struct userspace_mem_region *region;
        for (region = vm->userspace_mem_region_head; region;
             region = region->next) {
                if ((gpa >= region->region.guest_phys_addr)
                        && (gpa <= (region->region.guest_phys_addr
                                + region->region.memory_size - 1)))
                        return (void *) ((uintptr_t) region->host_mem
                                + (gpa - region->region.guest_phys_addr));
        }

        TEST_ASSERT(false, "No vm physical memory at 0x%lx", gpa);
        return NULL;
}

/*
 * Address Host Virtual to VM Physical
 *
 * Input Args:
 *   vm - Virtual Machine
 *   hva - Host virtual address
 *
 * Output Args: None
 *
 * Return:
 *   Equivalent VM physical address
 *
 * Locates the memory region containing the host virtual address given
 * by hva, within the VM given by vm.  When found, the equivalent
 * VM physical address is returned. A TEST_ASSERT failure occurs if no
 * region containing hva exists.
 */
vm_paddr_t addr_hva2gpa(struct kvm_vm *vm, void *hva)
{
        struct userspace_mem_region *region;
        for (region = vm->userspace_mem_region_head; region;
             region = region->next) {
                if ((hva >= region->host_mem)
                        && (hva <= (region->host_mem
                                + region->region.memory_size - 1)))
                        return (vm_paddr_t) ((uintptr_t)
                                region->region.guest_phys_addr
                                + (hva - (uintptr_t) region->host_mem));
        }

        TEST_ASSERT(false, "No mapping to a guest physical address, "
                "hva: %p", hva);
        return -1;
}

/*
 * VM Create IRQ Chip
 *
 * Input Args:
 *   vm - Virtual Machine
 *
 * Output Args: None
 *
 * Return: None
 *
 * Creates an interrupt controller chip for the VM specified by vm.
 */
void vm_create_irqchip(struct kvm_vm *vm)
{
        int ret;

        ret = ioctl(vm->fd, KVM_CREATE_IRQCHIP, 0);
        TEST_ASSERT(ret == 0, "KVM_CREATE_IRQCHIP IOCTL failed, "
                "rc: %i errno: %i", ret, errno);

        vm->has_irqchip = true;
}

/*
 * VM VCPU State
 *
 * Input Args:
 *   vm - Virtual Machine
 *   vcpuid - VCPU ID
 *
 * Output Args: None
 *
 * Return:
 *   Pointer to structure that describes the state of the VCPU.
 *
 * Locates and returns a pointer to a structure that describes the
 * state of the VCPU with the given vcpuid.
 */
struct kvm_run *vcpu_state(struct kvm_vm *vm, uint32_t vcpuid)
{
        struct vcpu *vcpu = vcpu_find(vm, vcpuid);
        TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);

        return vcpu->state;
}

/*
 * VM VCPU Run
 *
 * Input Args:
 *   vm - Virtual Machine
 *   vcpuid - VCPU ID
 *
 * Output Args: None
 *
 * Return: None
 *
 * Switch to executing the code for the VCPU given by vcpuid, within the VM
 * given by vm.
 */
void vcpu_run(struct kvm_vm *vm, uint32_t vcpuid)
{
        int ret = _vcpu_run(vm, vcpuid);
        TEST_ASSERT(ret == 0, "KVM_RUN IOCTL failed, "
                "rc: %i errno: %i", ret, errno);
}

int _vcpu_run(struct kvm_vm *vm, uint32_t vcpuid)
{
        struct vcpu *vcpu = vcpu_find(vm, vcpuid);
        int rc;

        TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);
        do {
                rc = ioctl(vcpu->fd, KVM_RUN, NULL);
        } while (rc == -1 && errno == EINTR);
        return rc;
}

void vcpu_run_complete_io(struct kvm_vm *vm, uint32_t vcpuid)
{
        struct vcpu *vcpu = vcpu_find(vm, vcpuid);
        int ret;

        TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);

        vcpu->state->immediate_exit = 1;
        ret = ioctl(vcpu->fd, KVM_RUN, NULL);
        vcpu->state->immediate_exit = 0;

        TEST_ASSERT(ret == -1 && errno == EINTR,
                    "KVM_RUN IOCTL didn't exit immediately, rc: %i, errno: %i",
                    ret, errno);
}

/*
 * VM VCPU Set MP State
 *
 * Input Args:
 *   vm - Virtual Machine
 *   vcpuid - VCPU ID
 *   mp_state - mp_state to be set
 *
 * Output Args: None
 *
 * Return: None
 *
 * Sets the MP state of the VCPU given by vcpuid, to the state given
 * by mp_state.
 */
void vcpu_set_mp_state(struct kvm_vm *vm, uint32_t vcpuid,
                       struct kvm_mp_state *mp_state)
{
        struct vcpu *vcpu = vcpu_find(vm, vcpuid);
        int ret;

        TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);

        ret = ioctl(vcpu->fd, KVM_SET_MP_STATE, mp_state);
        TEST_ASSERT(ret == 0, "KVM_SET_MP_STATE IOCTL failed, "
                "rc: %i errno: %i", ret, errno);
}

/*
 * VM VCPU Regs Get
 *
 * Input Args:
 *   vm - Virtual Machine
 *   vcpuid - VCPU ID
 *
 * Output Args:
 *   regs - current state of VCPU regs
 *
 * Return: None
 *
 * Obtains the current register state for the VCPU specified by vcpuid
 * and stores it at the location given by regs.
 */
void vcpu_regs_get(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_regs *regs)
{
        struct vcpu *vcpu = vcpu_find(vm, vcpuid);
        int ret;

        TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);

        ret = ioctl(vcpu->fd, KVM_GET_REGS, regs);
        TEST_ASSERT(ret == 0, "KVM_GET_REGS failed, rc: %i errno: %i",
                ret, errno);
}

/*
 * VM VCPU Regs Set
 *
 * Input Args:
 *   vm - Virtual Machine
 *   vcpuid - VCPU ID
 *   regs - Values to set VCPU regs to
 *
 * Output Args: None
 *
 * Return: None
 *
 * Sets the regs of the VCPU specified by vcpuid to the values
 * given by regs.
 */
void vcpu_regs_set(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_regs *regs)
{
        struct vcpu *vcpu = vcpu_find(vm, vcpuid);
        int ret;

        TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);

        ret = ioctl(vcpu->fd, KVM_SET_REGS, regs);
        TEST_ASSERT(ret == 0, "KVM_SET_REGS failed, rc: %i errno: %i",
                ret, errno);
}

void vcpu_events_get(struct kvm_vm *vm, uint32_t vcpuid,
                     struct kvm_vcpu_events *events)
{
        struct vcpu *vcpu = vcpu_find(vm, vcpuid);
        int ret;

        TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);

        ret = ioctl(vcpu->fd, KVM_GET_VCPU_EVENTS, events);
        TEST_ASSERT(ret == 0, "KVM_GET_VCPU_EVENTS, failed, rc: %i errno: %i",
                ret, errno);
}

void vcpu_events_set(struct kvm_vm *vm, uint32_t vcpuid,
                     struct kvm_vcpu_events *events)
{
        struct vcpu *vcpu = vcpu_find(vm, vcpuid);
        int ret;

        TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);

        ret = ioctl(vcpu->fd, KVM_SET_VCPU_EVENTS, events);
        TEST_ASSERT(ret == 0, "KVM_SET_VCPU_EVENTS, failed, rc: %i errno: %i",
                ret, errno);
}

/*
 * VM VCPU System Regs Get
 *
 * Input Args:
 *   vm - Virtual Machine
 *   vcpuid - VCPU ID
 *
 * Output Args:
 *   sregs - current state of VCPU system regs
 *
 * Return: None
 *
 * Obtains the current system register state for the VCPU specified by
 * vcpuid and stores it at the location given by sregs.
 */
void vcpu_sregs_get(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_sregs *sregs)
{
        struct vcpu *vcpu = vcpu_find(vm, vcpuid);
        int ret;

        TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);

        ret = ioctl(vcpu->fd, KVM_GET_SREGS, sregs);
        TEST_ASSERT(ret == 0, "KVM_GET_SREGS failed, rc: %i errno: %i",
                ret, errno);
}

/*
 * VM VCPU System Regs Set
 *
 * Input Args:
 *   vm - Virtual Machine
 *   vcpuid - VCPU ID
 *   sregs - Values to set VCPU system regs to
 *
 * Output Args: None
 *
 * Return: None
 *
 * Sets the system regs of the VCPU specified by vcpuid to the values
 * given by sregs.
 */
void vcpu_sregs_set(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_sregs *sregs)
{
        int ret = _vcpu_sregs_set(vm, vcpuid, sregs);
        TEST_ASSERT(ret == 0, "KVM_RUN IOCTL failed, "
                "rc: %i errno: %i", ret, errno);
}

int _vcpu_sregs_set(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_sregs *sregs)
{
        struct vcpu *vcpu = vcpu_find(vm, vcpuid);
        int ret;

        TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);

        return ioctl(vcpu->fd, KVM_SET_SREGS, sregs);
}

/*
 * VCPU Ioctl
 *
 * Input Args:
 *   vm - Virtual Machine
 *   vcpuid - VCPU ID
 *   cmd - Ioctl number
 *   arg - Argument to pass to the ioctl
 *
 * Return: None
 *
 * Issues an arbitrary ioctl on a VCPU fd.
 */
void vcpu_ioctl(struct kvm_vm *vm, uint32_t vcpuid,
                unsigned long cmd, void *arg)
{
        int ret;

        ret = _vcpu_ioctl(vm, vcpuid, cmd, arg);
        TEST_ASSERT(ret == 0, "vcpu ioctl %lu failed, rc: %i errno: %i (%s)",
                cmd, ret, errno, strerror(errno));
}

int _vcpu_ioctl(struct kvm_vm *vm, uint32_t vcpuid,
                unsigned long cmd, void *arg)
{
        struct vcpu *vcpu = vcpu_find(vm, vcpuid);
        int ret;

        TEST_ASSERT(vcpu != NULL, "vcpu not found, vcpuid: %u", vcpuid);

        ret = ioctl(vcpu->fd, cmd, arg);

        return ret;
}

/*
 * VM Ioctl
 *
 * Input Args:
 *   vm - Virtual Machine
 *   cmd - Ioctl number
 *   arg - Argument to pass to the ioctl
 *
 * Return: None
 *
 * Issues an arbitrary ioctl on a VM fd.
 */
void vm_ioctl(struct kvm_vm *vm, unsigned long cmd, void *arg)
{
        int ret;

        ret = ioctl(vm->fd, cmd, arg);
        TEST_ASSERT(ret == 0, "vm ioctl %lu failed, rc: %i errno: %i (%s)",
                cmd, ret, errno, strerror(errno));
}

/*
 * VM Dump
 *
 * Input Args:
 *   vm - Virtual Machine
 *   indent - Left margin indent amount
 *
 * Output Args:
 *   stream - Output FILE stream
 *
 * Return: None
 *
 * Dumps the current state of the VM given by vm, to the FILE stream
 * given by stream.
 */
void vm_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent)
{
        struct userspace_mem_region *region;
        struct vcpu *vcpu;

        fprintf(stream, "%*smode: 0x%x\n", indent, "", vm->mode);
        fprintf(stream, "%*sfd: %i\n", indent, "", vm->fd);
        fprintf(stream, "%*spage_size: 0x%x\n", indent, "", vm->page_size);
        fprintf(stream, "%*sMem Regions:\n", indent, "");
        for (region = vm->userspace_mem_region_head; region;
                region = region->next) {
                fprintf(stream, "%*sguest_phys: 0x%lx size: 0x%lx "
                        "host_virt: %p\n", indent + 2, "",
                        (uint64_t) region->region.guest_phys_addr,
                        (uint64_t) region->region.memory_size,
                        region->host_mem);
                fprintf(stream, "%*sunused_phy_pages: ", indent + 2, "");
                sparsebit_dump(stream, region->unused_phy_pages, 0);
        }
        fprintf(stream, "%*sMapped Virtual Pages:\n", indent, "");
        sparsebit_dump(stream, vm->vpages_mapped, indent + 2);
        fprintf(stream, "%*spgd_created: %u\n", indent, "",
                vm->pgd_created);
        if (vm->pgd_created) {
                fprintf(stream, "%*sVirtual Translation Tables:\n",
                        indent + 2, "");
                virt_dump(stream, vm, indent + 4);
        }
        fprintf(stream, "%*sVCPUs:\n", indent, "");
        for (vcpu = vm->vcpu_head; vcpu; vcpu = vcpu->next)
                vcpu_dump(stream, vm, vcpu->id, indent + 2);
}

/* Known KVM exit reasons */
static struct exit_reason {
        unsigned int reason;
        const char *name;
} exit_reasons_known[] = {
        {KVM_EXIT_UNKNOWN, "UNKNOWN"},
        {KVM_EXIT_EXCEPTION, "EXCEPTION"},
        {KVM_EXIT_IO, "IO"},
        {KVM_EXIT_HYPERCALL, "HYPERCALL"},
        {KVM_EXIT_DEBUG, "DEBUG"},
        {KVM_EXIT_HLT, "HLT"},
        {KVM_EXIT_MMIO, "MMIO"},
        {KVM_EXIT_IRQ_WINDOW_OPEN, "IRQ_WINDOW_OPEN"},
        {KVM_EXIT_SHUTDOWN, "SHUTDOWN"},
        {KVM_EXIT_FAIL_ENTRY, "FAIL_ENTRY"},
        {KVM_EXIT_INTR, "INTR"},
        {KVM_EXIT_SET_TPR, "SET_TPR"},
        {KVM_EXIT_TPR_ACCESS, "TPR_ACCESS"},
        {KVM_EXIT_S390_SIEIC, "S390_SIEIC"},
        {KVM_EXIT_S390_RESET, "S390_RESET"},
        {KVM_EXIT_DCR, "DCR"},
        {KVM_EXIT_NMI, "NMI"},
        {KVM_EXIT_INTERNAL_ERROR, "INTERNAL_ERROR"},
        {KVM_EXIT_OSI, "OSI"},
        {KVM_EXIT_PAPR_HCALL, "PAPR_HCALL"},
#ifdef KVM_EXIT_MEMORY_NOT_PRESENT
        {KVM_EXIT_MEMORY_NOT_PRESENT, "MEMORY_NOT_PRESENT"},
#endif
};

/*
 * Exit Reason String
 *
 * Input Args:
 *   exit_reason - Exit reason
 *
 * Output Args: None
 *
 * Return:
 *   Constant string pointer describing the exit reason.
 *
 * Locates and returns a constant string that describes the KVM exit
 * reason given by exit_reason.  If no such string is found, a constant
 * string of "Unknown" is returned.
 */
const char *exit_reason_str(unsigned int exit_reason)
{
        unsigned int n1;

        for (n1 = 0; n1 < ARRAY_SIZE(exit_reasons_known); n1++) {
                if (exit_reason == exit_reasons_known[n1].reason)
                        return exit_reasons_known[n1].name;
        }

        return "Unknown";
}

/*
 * Physical Contiguous Page Allocator
 *
 * Input Args:
 *   vm - Virtual Machine
 *   num - number of pages
 *   paddr_min - Physical address minimum
 *   memslot - Memory region to allocate page from
 *
 * Output Args: None
 *
 * Return:
 *   Starting physical address
 *
 * Within the VM specified by vm, locates a range of available physical
 * pages at or above paddr_min. If found, the pages are marked as in use
 * and their base address is returned. A TEST_ASSERT failure occurs if
 * not enough pages are available at or above paddr_min.
 */
vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
                              vm_paddr_t paddr_min, uint32_t memslot)
{
        struct userspace_mem_region *region;
        sparsebit_idx_t pg, base;

        TEST_ASSERT(num > 0, "Must allocate at least one page");

        TEST_ASSERT((paddr_min % vm->page_size) == 0, "Min physical address "
                "not divisible by page size.\n"
                "  paddr_min: 0x%lx page_size: 0x%x",
                paddr_min, vm->page_size);

        region = memslot2region(vm, memslot);
        base = pg = paddr_min >> vm->page_shift;

        do {
                for (; pg < base + num; ++pg) {
                        if (!sparsebit_is_set(region->unused_phy_pages, pg)) {
                                base = pg = sparsebit_next_set(region->unused_phy_pages, pg);
                                break;
                        }
                }
        } while (pg && pg != base + num);

        if (pg == 0) {
                fprintf(stderr, "No guest physical page available, "
                        "paddr_min: 0x%lx page_size: 0x%x memslot: %u\n",
                        paddr_min, vm->page_size, memslot);
                fputs("---- vm dump ----\n", stderr);
                vm_dump(stderr, vm, 2);
                abort();
        }

        for (pg = base; pg < base + num; ++pg)
                sparsebit_clear(region->unused_phy_pages, pg);

        return base * vm->page_size;
}

vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min,
                             uint32_t memslot)
{
        return vm_phy_pages_alloc(vm, 1, paddr_min, memslot);
}

/*
 * Address Guest Virtual to Host Virtual
 *
 * Input Args:
 *   vm - Virtual Machine
 *   gva - VM virtual address
 *
 * Output Args: None
 *
 * Return:
 *   Equivalent host virtual address
 */
void *addr_gva2hva(struct kvm_vm *vm, vm_vaddr_t gva)
{
        return addr_gpa2hva(vm, addr_gva2gpa(vm, gva));
}