// SPDX-License-Identifier: GPL-2.0-only
#include <sys/ioctl.h>
#include <sys/mman.h>

#include <linux/sizes.h>
#include <linux/vfio.h>

#include <libvfio.h>

#include "kselftest_harness.h"

static const char *device_bdf;

#define ASSERT_NO_MSI(_eventfd) do {                    \
        u64 __value;                                    \
                                                        \
        ASSERT_EQ(-1, read(_eventfd, &__value, 8));     \
        ASSERT_EQ(EAGAIN, errno);                       \
} while (0)

static void region_setup(struct iommu *iommu,
                         struct iova_allocator *iova_allocator,
                         struct dma_region *region, u64 size)
{
        const int flags = MAP_SHARED | MAP_ANONYMOUS;
        const int prot = PROT_READ | PROT_WRITE;
        void *vaddr;

        vaddr = mmap(NULL, size, prot, flags, -1, 0);
        VFIO_ASSERT_NE(vaddr, MAP_FAILED);

        region->vaddr = vaddr;
        region->iova = iova_allocator_alloc(iova_allocator, size);
        region->size = size;

        iommu_map(iommu, region);
}

static void region_teardown(struct iommu *iommu, struct dma_region *region)
{
        iommu_unmap(iommu, region);
        VFIO_ASSERT_EQ(munmap(region->vaddr, region->size), 0);
}

FIXTURE(vfio_pci_driver_test) {
        struct iommu *iommu;
        struct vfio_pci_device *device;
        struct iova_allocator *iova_allocator;
        struct dma_region memcpy_region;
        void *vaddr;
        int msi_fd;

        u64 size;
        void *src;
        void *dst;
        iova_t src_iova;
        iova_t dst_iova;
        iova_t unmapped_iova;
};

FIXTURE_VARIANT(vfio_pci_driver_test) {
        const char *iommu_mode;
};

#define FIXTURE_VARIANT_ADD_IOMMU_MODE(_iommu_mode)             \
FIXTURE_VARIANT_ADD(vfio_pci_driver_test, _iommu_mode) {        \
        .iommu_mode = #_iommu_mode,                             \
}

FIXTURE_VARIANT_ADD_ALL_IOMMU_MODES();

FIXTURE_SETUP(vfio_pci_driver_test)
{
        struct vfio_pci_driver *driver;

        self->iommu = iommu_init(variant->iommu_mode);
        self->device = vfio_pci_device_init(device_bdf, self->iommu);
        self->iova_allocator = iova_allocator_init(self->iommu);

        driver = &self->device->driver;

        region_setup(self->iommu, self->iova_allocator, &self->memcpy_region, SZ_1G);
        region_setup(self->iommu, self->iova_allocator, &driver->region, SZ_2M);

        /* Any IOVA that doesn't overlap memcpy_region and driver->region. */
        self->unmapped_iova = iova_allocator_alloc(self->iova_allocator, SZ_1G);

        vfio_pci_driver_init(self->device);
        self->msi_fd = self->device->msi_eventfds[driver->msi];

        /*
         * Use the maximum size supported by the device for memcpy operations,
         * slimmed down to fit into the memcpy region (divided by 2 so src and
         * dst regions do not overlap).
         */
        self->size = self->device->driver.max_memcpy_size;
        self->size = min(self->size, self->memcpy_region.size / 2);

        self->src = self->memcpy_region.vaddr;
        self->dst = self->src + self->size;

        self->src_iova = to_iova(self->device, self->src);
        self->dst_iova = to_iova(self->device, self->dst);
}

FIXTURE_TEARDOWN(vfio_pci_driver_test)
{
        struct vfio_pci_driver *driver = &self->device->driver;

        vfio_pci_driver_remove(self->device);

        region_teardown(self->iommu, &self->memcpy_region);
        region_teardown(self->iommu, &driver->region);

        iova_allocator_cleanup(self->iova_allocator);
        vfio_pci_device_cleanup(self->device);
        iommu_cleanup(self->iommu);
}

TEST_F(vfio_pci_driver_test, init_remove)
{
        int i;

        for (i = 0; i < 10; i++) {
                vfio_pci_driver_remove(self->device);
                vfio_pci_driver_init(self->device);
        }
}

TEST_F(vfio_pci_driver_test, memcpy_success)
{
        fcntl_set_nonblock(self->msi_fd);

        memset(self->src, 'x', self->size);
        memset(self->dst, 'y', self->size);

        ASSERT_EQ(0, vfio_pci_driver_memcpy(self->device,
                                            self->src_iova,
                                            self->dst_iova,
                                            self->size));

        ASSERT_EQ(0, memcmp(self->src, self->dst, self->size));
        ASSERT_NO_MSI(self->msi_fd);
}

TEST_F(vfio_pci_driver_test, memcpy_from_unmapped_iova)
{
        fcntl_set_nonblock(self->msi_fd);

        /*
         * Ignore the return value since not all devices will detect and report
         * accesses to unmapped IOVAs as errors.
         */
        vfio_pci_driver_memcpy(self->device, self->unmapped_iova,
                               self->dst_iova, self->size);

        ASSERT_NO_MSI(self->msi_fd);
}

TEST_F(vfio_pci_driver_test, memcpy_to_unmapped_iova)
{
        fcntl_set_nonblock(self->msi_fd);

        /*
         * Ignore the return value since not all devices will detect and report
         * accesses to unmapped IOVAs as errors.
         */
        vfio_pci_driver_memcpy(self->device, self->src_iova,
                               self->unmapped_iova, self->size);

        ASSERT_NO_MSI(self->msi_fd);
}

TEST_F(vfio_pci_driver_test, send_msi)
{
        u64 value;

        vfio_pci_driver_send_msi(self->device);
        ASSERT_EQ(8, read(self->msi_fd, &value, 8));
        ASSERT_EQ(1, value);
}

TEST_F(vfio_pci_driver_test, mix_and_match)
{
        u64 value;
        int i;

        for (i = 0; i < 10; i++) {
                memset(self->src, 'x', self->size);
                memset(self->dst, 'y', self->size);

                ASSERT_EQ(0, vfio_pci_driver_memcpy(self->device,
                                                    self->src_iova,
                                                    self->dst_iova,
                                                    self->size));

                ASSERT_EQ(0, memcmp(self->src, self->dst, self->size));

                vfio_pci_driver_memcpy(self->device,
                                       self->unmapped_iova,
                                       self->dst_iova,
                                       self->size);

                vfio_pci_driver_send_msi(self->device);
                ASSERT_EQ(8, read(self->msi_fd, &value, 8));
                ASSERT_EQ(1, value);
        }
}

TEST_F_TIMEOUT(vfio_pci_driver_test, memcpy_storm, 60)
{
        struct vfio_pci_driver *driver = &self->device->driver;
        u64 total_size;
        u64 count;

        fcntl_set_nonblock(self->msi_fd);

        /*
         * Perform up to 250GiB worth of DMA reads and writes across several
         * memcpy operations. Some devices can support even more but the test
         * will take too long.
         */
        total_size = 250UL * SZ_1G;
        count = min(total_size / self->size, driver->max_memcpy_count);

        printf("Kicking off %lu memcpys of size 0x%lx\n", count, self->size);
        vfio_pci_driver_memcpy_start(self->device,
                                     self->src_iova,
                                     self->dst_iova,
                                     self->size, count);

        ASSERT_EQ(0, vfio_pci_driver_memcpy_wait(self->device));
        ASSERT_NO_MSI(self->msi_fd);
}

static bool device_has_selftests_driver(const char *bdf)
{
        struct vfio_pci_device *device;
        struct iommu *iommu;
        bool has_driver;

        iommu = iommu_init(default_iommu_mode);
        device = vfio_pci_device_init(device_bdf, iommu);

        has_driver = !!device->driver.ops;

        vfio_pci_device_cleanup(device);
        iommu_cleanup(iommu);

        return has_driver;
}

int main(int argc, char *argv[])
{
        device_bdf = vfio_selftests_get_bdf(&argc, argv);

        if (!device_has_selftests_driver(device_bdf)) {
                fprintf(stderr, "No driver found for device %s\n", device_bdf);
                return KSFT_SKIP;
        }

        return test_harness_run(argc, argv);
}