cachepc-qemu

Fork of AMDESE/qemu with changes for cachepc side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-qemu
Log | Files | Refs | Submodules | LICENSE | sfeed.txt

virtio-pci-modern.c (15180B)


      1/*
      2 * libqos VIRTIO 1.0 PCI driver
      3 *
      4 * Copyright (c) 2019 Red Hat, Inc
      5 *
      6 * This work is licensed under the terms of the GNU GPL, version 2 or later.
      7 * See the COPYING file in the top-level directory.
      8 */
      9
     10#include "qemu/osdep.h"
     11#include "standard-headers/linux/pci_regs.h"
     12#include "standard-headers/linux/virtio_pci.h"
     13#include "standard-headers/linux/virtio_config.h"
     14#include "virtio-pci-modern.h"
     15
     16static uint8_t config_readb(QVirtioDevice *d, uint64_t addr)
     17{
     18    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
     19    return qpci_io_readb(dev->pdev, dev->bar, dev->device_cfg_offset + addr);
     20}
     21
     22static uint16_t config_readw(QVirtioDevice *d, uint64_t addr)
     23{
     24    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
     25    return qpci_io_readw(dev->pdev, dev->bar, dev->device_cfg_offset + addr);
     26}
     27
     28static uint32_t config_readl(QVirtioDevice *d, uint64_t addr)
     29{
     30    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
     31    return qpci_io_readl(dev->pdev, dev->bar, dev->device_cfg_offset + addr);
     32}
     33
     34static uint64_t config_readq(QVirtioDevice *d, uint64_t addr)
     35{
     36    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
     37    return qpci_io_readq(dev->pdev, dev->bar, dev->device_cfg_offset + addr);
     38}
     39
     40static uint64_t get_features(QVirtioDevice *d)
     41{
     42    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
     43    uint64_t lo, hi;
     44
     45    qpci_io_writel(dev->pdev, dev->bar, dev->common_cfg_offset +
     46                   offsetof(struct virtio_pci_common_cfg,
     47                            device_feature_select),
     48                   0);
     49    lo = qpci_io_readl(dev->pdev, dev->bar, dev->common_cfg_offset +
     50                       offsetof(struct virtio_pci_common_cfg, device_feature));
     51
     52    qpci_io_writel(dev->pdev, dev->bar, dev->common_cfg_offset +
     53                   offsetof(struct virtio_pci_common_cfg,
     54                            device_feature_select),
     55                   1);
     56    hi = qpci_io_readl(dev->pdev, dev->bar, dev->common_cfg_offset +
     57                       offsetof(struct virtio_pci_common_cfg, device_feature));
     58
     59    return (hi << 32) | lo;
     60}
     61
     62static void set_features(QVirtioDevice *d, uint64_t features)
     63{
     64    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
     65
     66    /* Drivers must enable VIRTIO 1.0 or else use the Legacy interface */
     67    g_assert_cmphex(features & (1ull << VIRTIO_F_VERSION_1), !=, 0);
     68
     69    qpci_io_writel(dev->pdev, dev->bar, dev->common_cfg_offset +
     70                   offsetof(struct virtio_pci_common_cfg,
     71                            guest_feature_select),
     72                   0);
     73    qpci_io_writel(dev->pdev, dev->bar, dev->common_cfg_offset +
     74                   offsetof(struct virtio_pci_common_cfg,
     75                            guest_feature),
     76                   features);
     77    qpci_io_writel(dev->pdev, dev->bar, dev->common_cfg_offset +
     78                   offsetof(struct virtio_pci_common_cfg,
     79                            guest_feature_select),
     80                   1);
     81    qpci_io_writel(dev->pdev, dev->bar, dev->common_cfg_offset +
     82                   offsetof(struct virtio_pci_common_cfg,
     83                            guest_feature),
     84                   features >> 32);
     85}
     86
     87static uint64_t get_guest_features(QVirtioDevice *d)
     88{
     89    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
     90    uint64_t lo, hi;
     91
     92    qpci_io_writel(dev->pdev, dev->bar, dev->common_cfg_offset +
     93                   offsetof(struct virtio_pci_common_cfg,
     94                            guest_feature_select),
     95                   0);
     96    lo = qpci_io_readl(dev->pdev, dev->bar, dev->common_cfg_offset +
     97                       offsetof(struct virtio_pci_common_cfg, guest_feature));
     98
     99    qpci_io_writel(dev->pdev, dev->bar, dev->common_cfg_offset +
    100                   offsetof(struct virtio_pci_common_cfg,
    101                            guest_feature_select),
    102                   1);
    103    hi = qpci_io_readl(dev->pdev, dev->bar, dev->common_cfg_offset +
    104                       offsetof(struct virtio_pci_common_cfg, guest_feature));
    105
    106    return (hi << 32) | lo;
    107}
    108
    109static uint8_t get_status(QVirtioDevice *d)
    110{
    111    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
    112
    113    return qpci_io_readb(dev->pdev, dev->bar, dev->common_cfg_offset +
    114                         offsetof(struct virtio_pci_common_cfg,
    115                                  device_status));
    116}
    117
    118static void set_status(QVirtioDevice *d, uint8_t status)
    119{
    120    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
    121
    122    return qpci_io_writeb(dev->pdev, dev->bar, dev->common_cfg_offset +
    123                          offsetof(struct virtio_pci_common_cfg,
    124                                   device_status),
    125                          status);
    126}
    127
    128static bool get_msix_status(QVirtioPCIDevice *dev, uint32_t msix_entry,
    129                            uint32_t msix_addr, uint32_t msix_data)
    130{
    131    uint32_t data;
    132
    133    g_assert_cmpint(msix_entry, !=, -1);
    134    if (qpci_msix_masked(dev->pdev, msix_entry)) {
    135        /* No ISR checking should be done if masked, but read anyway */
    136        return qpci_msix_pending(dev->pdev, msix_entry);
    137    }
    138
    139    data = qtest_readl(dev->pdev->bus->qts, msix_addr);
    140    if (data == msix_data) {
    141        qtest_writel(dev->pdev->bus->qts, msix_addr, 0);
    142        return true;
    143    } else {
    144        return false;
    145    }
    146}
    147
    148static bool get_queue_isr_status(QVirtioDevice *d, QVirtQueue *vq)
    149{
    150    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
    151
    152    if (dev->pdev->msix_enabled) {
    153        QVirtQueuePCI *vqpci = container_of(vq, QVirtQueuePCI, vq);
    154
    155        return get_msix_status(dev, vqpci->msix_entry, vqpci->msix_addr,
    156                               vqpci->msix_data);
    157    }
    158
    159    return qpci_io_readb(dev->pdev, dev->bar, dev->isr_cfg_offset) & 1;
    160}
    161
    162static bool get_config_isr_status(QVirtioDevice *d)
    163{
    164    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
    165
    166    if (dev->pdev->msix_enabled) {
    167        return get_msix_status(dev, dev->config_msix_entry,
    168                               dev->config_msix_addr, dev->config_msix_data);
    169    }
    170
    171    return qpci_io_readb(dev->pdev, dev->bar, dev->isr_cfg_offset) & 2;
    172}
    173
    174static void wait_config_isr_status(QVirtioDevice *d, gint64 timeout_us)
    175{
    176    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
    177    gint64 start_time = g_get_monotonic_time();
    178
    179    do {
    180        g_assert(g_get_monotonic_time() - start_time <= timeout_us);
    181        qtest_clock_step(dev->pdev->bus->qts, 100);
    182    } while (!get_config_isr_status(d));
    183}
    184
    185static void queue_select(QVirtioDevice *d, uint16_t index)
    186{
    187    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
    188
    189    qpci_io_writew(dev->pdev, dev->bar, dev->common_cfg_offset +
    190                   offsetof(struct virtio_pci_common_cfg, queue_select),
    191                   index);
    192}
    193
    194static uint16_t get_queue_size(QVirtioDevice *d)
    195{
    196    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
    197
    198    return qpci_io_readw(dev->pdev, dev->bar, dev->common_cfg_offset +
    199                         offsetof(struct virtio_pci_common_cfg, queue_size));
    200}
    201
    202static void set_queue_address(QVirtioDevice *d, QVirtQueue *vq)
    203{
    204    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
    205
    206    qpci_io_writel(dev->pdev, dev->bar, dev->common_cfg_offset +
    207                   offsetof(struct virtio_pci_common_cfg, queue_desc_lo),
    208                   vq->desc);
    209    qpci_io_writel(dev->pdev, dev->bar, dev->common_cfg_offset +
    210                   offsetof(struct virtio_pci_common_cfg, queue_desc_hi),
    211                   vq->desc >> 32);
    212
    213    qpci_io_writel(dev->pdev, dev->bar, dev->common_cfg_offset +
    214                   offsetof(struct virtio_pci_common_cfg, queue_avail_lo),
    215                   vq->avail);
    216    qpci_io_writel(dev->pdev, dev->bar, dev->common_cfg_offset +
    217                   offsetof(struct virtio_pci_common_cfg, queue_avail_hi),
    218                   vq->avail >> 32);
    219
    220    qpci_io_writel(dev->pdev, dev->bar, dev->common_cfg_offset +
    221                   offsetof(struct virtio_pci_common_cfg, queue_used_lo),
    222                   vq->used);
    223    qpci_io_writel(dev->pdev, dev->bar, dev->common_cfg_offset +
    224                   offsetof(struct virtio_pci_common_cfg, queue_used_hi),
    225                   vq->used >> 32);
    226}
    227
    228static QVirtQueue *virtqueue_setup(QVirtioDevice *d, QGuestAllocator *alloc,
    229                                   uint16_t index)
    230{
    231    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
    232    QVirtQueue *vq;
    233    QVirtQueuePCI *vqpci;
    234    uint16_t notify_off;
    235
    236    vq = qvirtio_pci_virtqueue_setup_common(d, alloc, index);
    237    vqpci = container_of(vq, QVirtQueuePCI, vq);
    238
    239    notify_off = qpci_io_readw(dev->pdev, dev->bar, dev->common_cfg_offset +
    240                               offsetof(struct virtio_pci_common_cfg,
    241                                        queue_notify_off));
    242
    243    vqpci->notify_offset = dev->notify_cfg_offset +
    244                           notify_off * dev->notify_off_multiplier;
    245
    246    qpci_io_writew(dev->pdev, dev->bar, dev->common_cfg_offset +
    247                   offsetof(struct virtio_pci_common_cfg, queue_enable), 1);
    248
    249    return vq;
    250}
    251
    252static void virtqueue_kick(QVirtioDevice *d, QVirtQueue *vq)
    253{
    254    QVirtioPCIDevice *dev = container_of(d, QVirtioPCIDevice, vdev);
    255    QVirtQueuePCI *vqpci = container_of(vq, QVirtQueuePCI, vq);
    256
    257    qpci_io_writew(dev->pdev, dev->bar, vqpci->notify_offset, vq->index);
    258}
    259
    260static const QVirtioBus qvirtio_pci_virtio_1 = {
    261    .config_readb = config_readb,
    262    .config_readw = config_readw,
    263    .config_readl = config_readl,
    264    .config_readq = config_readq,
    265    .get_features = get_features,
    266    .set_features = set_features,
    267    .get_guest_features = get_guest_features,
    268    .get_status = get_status,
    269    .set_status = set_status,
    270    .get_queue_isr_status = get_queue_isr_status,
    271    .wait_config_isr_status = wait_config_isr_status,
    272    .queue_select = queue_select,
    273    .get_queue_size = get_queue_size,
    274    .set_queue_address = set_queue_address,
    275    .virtqueue_setup = virtqueue_setup,
    276    .virtqueue_cleanup = qvirtio_pci_virtqueue_cleanup_common,
    277    .virtqueue_kick = virtqueue_kick,
    278};
    279
    280static void set_config_vector(QVirtioPCIDevice *d, uint16_t entry)
    281{
    282    uint16_t vector;
    283
    284    qpci_io_writew(d->pdev, d->bar, d->common_cfg_offset +
    285                   offsetof(struct virtio_pci_common_cfg, msix_config), entry);
    286    vector = qpci_io_readw(d->pdev, d->bar, d->common_cfg_offset +
    287                           offsetof(struct virtio_pci_common_cfg,
    288                                    msix_config));
    289    g_assert_cmphex(vector, !=, VIRTIO_MSI_NO_VECTOR);
    290}
    291
    292static void set_queue_vector(QVirtioPCIDevice *d, uint16_t vq_idx,
    293                             uint16_t entry)
    294{
    295    uint16_t vector;
    296
    297    queue_select(&d->vdev, vq_idx);
    298    qpci_io_writew(d->pdev, d->bar, d->common_cfg_offset +
    299                   offsetof(struct virtio_pci_common_cfg, queue_msix_vector),
    300                   entry);
    301    vector = qpci_io_readw(d->pdev, d->bar, d->common_cfg_offset +
    302                           offsetof(struct virtio_pci_common_cfg,
    303                                    queue_msix_vector));
    304    g_assert_cmphex(vector, !=, VIRTIO_MSI_NO_VECTOR);
    305}
    306
    307static const QVirtioPCIMSIXOps qvirtio_pci_msix_ops_virtio_1 = {
    308    .set_config_vector = set_config_vector,
    309    .set_queue_vector = set_queue_vector,
    310};
    311
    312static bool probe_device_type(QVirtioPCIDevice *dev)
    313{
    314    uint16_t vendor_id;
    315    uint16_t device_id;
    316
    317    /* "Drivers MUST match devices with the PCI Vendor ID 0x1AF4" */
    318    vendor_id = qpci_config_readw(dev->pdev, PCI_VENDOR_ID);
    319    if (vendor_id != 0x1af4) {
    320        return false;
    321    }
    322
    323    /*
    324     * "Any PCI device with ... PCI Device ID 0x1000 through 0x107F inclusive
    325     * is a virtio device"
    326     */
    327    device_id = qpci_config_readw(dev->pdev, PCI_DEVICE_ID);
    328    if (device_id < 0x1000 || device_id > 0x107f) {
    329        return false;
    330    }
    331
    332    /*
    333     * "Devices MAY utilize a Transitional PCI Device ID range, 0x1000 to
    334     * 0x103F depending on the device type"
    335     */
    336    if (device_id < 0x1040) {
    337        /*
    338         * "Transitional devices MUST have the PCI Subsystem Device ID matching
    339         * the Virtio Device ID"
    340         */
    341        dev->vdev.device_type = qpci_config_readw(dev->pdev, PCI_SUBSYSTEM_ID);
    342    } else {
    343        /*
    344         * "The PCI Device ID is calculated by adding 0x1040 to the Virtio
    345         * Device ID"
    346         */
    347        dev->vdev.device_type = device_id - 0x1040;
    348    }
    349
    350    return true;
    351}
    352
    353/* Find the first VIRTIO 1.0 PCI structure for a given type */
    354static bool find_structure(QVirtioPCIDevice *dev, uint8_t cfg_type,
    355                           uint8_t *bar, uint32_t *offset, uint32_t *length,
    356                           uint8_t *cfg_addr)
    357{
    358    uint8_t addr = 0;
    359
    360    while ((addr = qpci_find_capability(dev->pdev, PCI_CAP_ID_VNDR,
    361                                        addr)) != 0) {
    362        uint8_t type;
    363
    364        type = qpci_config_readb(dev->pdev,
    365                addr + offsetof(struct virtio_pci_cap, cfg_type));
    366        if (type != cfg_type) {
    367            continue;
    368        }
    369
    370        *bar = qpci_config_readb(dev->pdev,
    371                addr + offsetof(struct virtio_pci_cap, bar));
    372        *offset = qpci_config_readl(dev->pdev,
    373                addr + offsetof(struct virtio_pci_cap, offset));
    374        *length = qpci_config_readl(dev->pdev,
    375                addr + offsetof(struct virtio_pci_cap, length));
    376        if (cfg_addr) {
    377            *cfg_addr = addr;
    378        }
    379
    380        return true;
    381    }
    382
    383    return false;
    384}
    385
    386static bool probe_device_layout(QVirtioPCIDevice *dev)
    387{
    388    uint8_t bar;
    389    uint8_t cfg_addr;
    390    uint32_t length;
    391
    392    /*
    393     * Due to the qpci_iomap() API we only support devices that put all
    394     * structures in the same PCI BAR.  Luckily this is true with QEMU.
    395     */
    396
    397    if (!find_structure(dev, VIRTIO_PCI_CAP_COMMON_CFG, &bar,
    398                        &dev->common_cfg_offset, &length, NULL)) {
    399        return false;
    400    }
    401    dev->bar_idx = bar;
    402
    403    if (!find_structure(dev, VIRTIO_PCI_CAP_NOTIFY_CFG, &bar,
    404                        &dev->notify_cfg_offset, &length, &cfg_addr)) {
    405        return false;
    406    }
    407    g_assert_cmphex(bar, ==, dev->bar_idx);
    408
    409    dev->notify_off_multiplier = qpci_config_readl(dev->pdev,
    410            cfg_addr + offsetof(struct virtio_pci_notify_cap,
    411                                notify_off_multiplier));
    412
    413    if (!find_structure(dev, VIRTIO_PCI_CAP_ISR_CFG, &bar,
    414                        &dev->isr_cfg_offset, &length, NULL)) {
    415        return false;
    416    }
    417    g_assert_cmphex(bar, ==, dev->bar_idx);
    418
    419    if (!find_structure(dev, VIRTIO_PCI_CAP_DEVICE_CFG, &bar,
    420                        &dev->device_cfg_offset, &length, NULL)) {
    421        return false;
    422    }
    423    g_assert_cmphex(bar, ==, dev->bar_idx);
    424
    425    return true;
    426}
    427
    428/* Probe a VIRTIO 1.0 device */
    429bool qvirtio_pci_init_virtio_1(QVirtioPCIDevice *dev)
    430{
    431    if (!probe_device_type(dev)) {
    432        return false;
    433    }
    434
    435    if (!probe_device_layout(dev)) {
    436        return false;
    437    }
    438
    439    dev->vdev.bus = &qvirtio_pci_virtio_1;
    440    dev->msix_ops = &qvirtio_pci_msix_ops_virtio_1;
    441    dev->vdev.big_endian = false;
    442    return true;
    443}