/*
 * QTest testcase for VirtIO 9P
 *
 * Copyright (c) 2014 SUSE LINUX Products GmbH
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or later.
 * See the COPYING file in the top-level directory.
 */

#include "qemu/osdep.h"
#include "libqtest.h"
#include "qemu-common.h"
#include "libqos/libqos-pc.h"
#include "libqos/libqos-spapr.h"
#include "libqos/virtio.h"
#include "libqos/virtio-pci.h"
#include "standard-headers/linux/virtio_ids.h"
#include "standard-headers/linux/virtio_pci.h"
#include "hw/9pfs/9p.h"

static const char mount_tag[] = "qtest";

typedef struct {
    QVirtioDevice *dev;
    QOSState *qs;
    QVirtQueue *vq;
    char *test_share;
} QVirtIO9P;

static QVirtIO9P *qvirtio_9p_start(const char *driver)
{
    const char *arch = qtest_get_arch();
    const char *cmd = "-fsdev local,id=fsdev0,security_model=none,path=%s "
                      "-device %s,fsdev=fsdev0,mount_tag=%s";
    QVirtIO9P *v9p = g_new0(QVirtIO9P, 1);

    v9p->test_share = g_strdup("/tmp/qtest.XXXXXX");
    g_assert_nonnull(mkdtemp(v9p->test_share));

    if (strcmp(arch, "i386") == 0 || strcmp(arch, "x86_64") == 0) {
        v9p->qs = qtest_pc_boot(cmd, v9p->test_share, driver, mount_tag);
    } else if (strcmp(arch, "ppc64") == 0) {
        v9p->qs = qtest_spapr_boot(cmd, v9p->test_share, driver, mount_tag);
    } else {
        g_printerr("virtio-9p tests are only available on x86 or ppc64\n");
        exit(EXIT_FAILURE);
    }

    return v9p;
}

static void qvirtio_9p_stop(QVirtIO9P *v9p)
{
    qtest_shutdown(v9p->qs);
    rmdir(v9p->test_share);
    g_free(v9p->test_share);
    g_free(v9p);
}

static QVirtIO9P *qvirtio_9p_pci_start(void)
{
    QVirtIO9P *v9p = qvirtio_9p_start("virtio-9p-pci");
    QVirtioPCIDevice *dev = qvirtio_pci_device_find(v9p->qs->pcibus,
                                                    VIRTIO_ID_9P);
    g_assert_nonnull(dev);
    g_assert_cmphex(dev->vdev.device_type, ==, VIRTIO_ID_9P);
    v9p->dev = (QVirtioDevice *) dev;

    qvirtio_pci_device_enable(dev);
    qvirtio_reset(v9p->dev);
    qvirtio_set_acknowledge(v9p->dev);
    qvirtio_set_driver(v9p->dev);

    v9p->vq = qvirtqueue_setup(v9p->dev, v9p->qs->alloc, 0);
    return v9p;
}

static void qvirtio_9p_pci_stop(QVirtIO9P *v9p)
{
    qvirtqueue_cleanup(v9p->dev->bus, v9p->vq, v9p->qs->alloc);
    qvirtio_pci_device_disable(container_of(v9p->dev, QVirtioPCIDevice, vdev));
    g_free(v9p->dev);
    qvirtio_9p_stop(v9p);
}

static void pci_config(QVirtIO9P *v9p)
{
    size_t tag_len = qvirtio_config_readw(v9p->dev, 0);
    char *tag;
    int i;

    g_assert_cmpint(tag_len, ==, strlen(mount_tag));

    tag = g_malloc(tag_len);
    for (i = 0; i < tag_len; i++) {
        tag[i] = qvirtio_config_readb(v9p->dev, i + 2);
    }
    g_assert_cmpmem(tag, tag_len, mount_tag, tag_len);
    g_free(tag);
}

#define P9_MAX_SIZE 4096 /* Max size of a T-message or R-message */

typedef struct {
    QVirtIO9P *v9p;
    uint16_t tag;
    uint64_t t_msg;
    uint32_t t_size;
    uint64_t r_msg;
    /* No r_size, it is hardcoded to P9_MAX_SIZE */
    size_t t_off;
    size_t r_off;
} P9Req;

static void v9fs_memwrite(P9Req *req, const void *addr, size_t len)
{
    memwrite(req->t_msg + req->t_off, addr, len);
    req->t_off += len;
}

static void v9fs_memskip(P9Req *req, size_t len)
{
    req->r_off += len;
}

static void v9fs_memrewind(P9Req *req, size_t len)
{
    req->r_off -= len;
}

static void v9fs_memread(P9Req *req, void *addr, size_t len)
{
    memread(req->r_msg + req->r_off, addr, len);
    req->r_off += len;
}

static void v9fs_uint16_write(P9Req *req, uint16_t val)
{
    uint16_t le_val = cpu_to_le16(val);

    v9fs_memwrite(req, &le_val, 2);
}

static void v9fs_uint16_read(P9Req *req, uint16_t *val)
{
    v9fs_memread(req, val, 2);
    le16_to_cpus(val);
}

static void v9fs_uint32_write(P9Req *req, uint32_t val)
{
    uint32_t le_val = cpu_to_le32(val);

    v9fs_memwrite(req, &le_val, 4);
}

static void v9fs_uint32_read(P9Req *req, uint32_t *val)
{
    v9fs_memread(req, val, 4);
    le32_to_cpus(val);
}

/* len[2] string[len] */
static uint16_t v9fs_string_size(const char *string)
{
    size_t len = strlen(string);

    g_assert_cmpint(len, <=, UINT16_MAX);

    return 2 + len;
}

static void v9fs_string_write(P9Req *req, const char *string)
{
    int len = strlen(string);

    g_assert_cmpint(len, <=, UINT16_MAX);

    v9fs_uint16_write(req, (uint16_t) len);
    v9fs_memwrite(req, string, len);
}

static void v9fs_string_read(P9Req *req, uint16_t *len, char **string)
{
    uint16_t local_len;

    v9fs_uint16_read(req, &local_len);
    if (len) {
        *len = local_len;
    }
    if (string) {
        *string = g_malloc(local_len);
        v9fs_memread(req, *string, local_len);
    } else {
        v9fs_memskip(req, local_len);
    }
}

 typedef struct {
    uint32_t size;
    uint8_t id;
    uint16_t tag;
} QEMU_PACKED P9Hdr;

static P9Req *v9fs_req_init(QVirtIO9P *v9p, uint32_t size, uint8_t id,
                            uint16_t tag)
{
    P9Req *req = g_new0(P9Req, 1);
    uint32_t t_size = 7 + size; /* 9P header has well-known size of 7 bytes */
    P9Hdr hdr = {
        .size = cpu_to_le32(t_size),
        .id = id,
        .tag = cpu_to_le16(tag)
    };

    g_assert_cmpint(t_size, <=, P9_MAX_SIZE);

    req->v9p = v9p;
    req->t_size = t_size;
    req->t_msg = guest_alloc(v9p->qs->alloc, req->t_size);
    v9fs_memwrite(req, &hdr, 7);
    req->tag = tag;
    return req;
}

static void v9fs_req_send(P9Req *req)
{
    QVirtIO9P *v9p = req->v9p;
    uint32_t free_head;

    req->r_msg = guest_alloc(v9p->qs->alloc, P9_MAX_SIZE);
    free_head = qvirtqueue_add(v9p->vq, req->t_msg, req->t_size, false, true);
    qvirtqueue_add(v9p->vq, req->r_msg, P9_MAX_SIZE, true, false);
    qvirtqueue_kick(v9p->dev, v9p->vq, free_head);
    req->t_off = 0;
}

static void v9fs_req_recv(P9Req *req, uint8_t id)
{
    QVirtIO9P *v9p = req->v9p;
    P9Hdr hdr;
    int i;

    for (i = 0; i < 10; i++) {
        qvirtio_wait_queue_isr(v9p->dev, v9p->vq, 1000 * 1000);

        v9fs_memread(req, &hdr, 7);
        le32_to_cpus(&hdr.size);
        le16_to_cpus(&hdr.tag);
        if (hdr.size >= 7) {
            break;
        }
        v9fs_memrewind(req, 7);
    }

    g_assert_cmpint(hdr.size, >=, 7);
    g_assert_cmpint(hdr.size, <=, P9_MAX_SIZE);
    g_assert_cmpint(hdr.tag, ==, req->tag);

    if (hdr.id != id && hdr.id == P9_RLERROR) {
        uint32_t err;
        v9fs_uint32_read(req, &err);
        g_printerr("Received Rlerror (%d) instead of Response %d\n", err, id);
        g_assert_not_reached();
    }
    g_assert_cmpint(hdr.id, ==, id);
}

static void v9fs_req_free(P9Req *req)
{
    QVirtIO9P *v9p = req->v9p;

    guest_free(v9p->qs->alloc, req->t_msg);
    guest_free(v9p->qs->alloc, req->r_msg);
    g_free(req);
}

/* size[4] Tversion tag[2] msize[4] version[s] */
static P9Req *v9fs_tversion(QVirtIO9P *v9p, uint32_t msize, const char *version)
{
    P9Req *req = v9fs_req_init(v9p, 4 + v9fs_string_size(version), P9_TVERSION,
                               P9_NOTAG);

    v9fs_uint32_write(req, msize);
    v9fs_string_write(req, version);
    v9fs_req_send(req);
    return req;
}

/* size[4] Rversion tag[2] msize[4] version[s] */
static void v9fs_rversion(P9Req *req, uint16_t *len, char **version)
{
    uint32_t msize;

    v9fs_req_recv(req, P9_RVERSION);
    v9fs_uint32_read(req, &msize);

    g_assert_cmpint(msize, ==, P9_MAX_SIZE);

    if (len || version) {
        v9fs_string_read(req, len, version);
    }

    v9fs_req_free(req);
}

static void fs_version(QVirtIO9P *v9p)
{
    const char *version = "9P2000.L";
    uint16_t server_len;
    char *server_version;
    P9Req *req;

    req = v9fs_tversion(v9p, P9_MAX_SIZE, version);
    v9fs_rversion(req, &server_len, &server_version);

    g_assert_cmpmem(server_version, server_len, version, strlen(version));

    g_free(server_version);
}

typedef void (*v9fs_test_fn)(QVirtIO9P *v9p);

static void v9fs_run_pci_test(gconstpointer data)
{
    v9fs_test_fn fn = data;
    QVirtIO9P *v9p = qvirtio_9p_pci_start();

    if (fn) {
        fn(v9p);
    }
    qvirtio_9p_pci_stop(v9p);
}

static void v9fs_qtest_pci_add(const char *path, v9fs_test_fn fn)
{
    qtest_add_data_func(path, fn, v9fs_run_pci_test);
}

int main(int argc, char **argv)
{
    g_test_init(&argc, &argv, NULL);
    v9fs_qtest_pci_add("/virtio/9p/pci/nop", NULL);
    v9fs_qtest_pci_add("/virtio/9p/pci/config", pci_config);
    v9fs_qtest_pci_add("/virtio/9p/pci/fs/version/basic", fs_version);

    return g_test_run();
}