For vfio pcie device, we could expose the extanded capability on PCIE bus. in order to avoid config space broken, we introduce a copy config for parsing extended caps. and rebuild the pcie extended config space.
Signed-off-by: Chen Fan <[email protected]> --- hw/vfio/pci.c | 83 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 82 insertions(+), 1 deletion(-) diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index 84e9d99..96cb52b 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -2482,6 +2482,21 @@ static uint8_t vfio_std_cap_max_size(PCIDevice *pdev, uint8_t pos) return next - pos; } + +static uint16_t vfio_ext_cap_max_size(const uint8_t *config, uint16_t pos) +{ + uint16_t tmp, next = PCIE_CONFIG_SPACE_SIZE - 1; + + for (tmp = PCI_CONFIG_SPACE_SIZE; tmp; + tmp = PCI_EXT_CAP_NEXT(pci_get_long(config + tmp))) { + if (tmp > pos && tmp < next) { + next = tmp; + } + } + + return next - pos; +} + static void vfio_set_word_bits(uint8_t *buf, uint16_t val, uint16_t mask) { pci_set_word(buf, (pci_get_word(buf) & ~mask) | val); @@ -2705,16 +2720,82 @@ static int vfio_add_std_cap(VFIOPCIDevice *vdev, uint8_t pos) return 0; } +static int vfio_add_ext_cap(VFIOPCIDevice *vdev, const uint8_t *config, + uint16_t pos) +{ + PCIDevice *pdev = &vdev->pdev; + uint32_t header; + uint16_t cap_id, next, size; + uint8_t cap_ver; + int ret; + + header = pci_get_long(config + pos); + cap_id = PCI_EXT_CAP_ID(header); + cap_ver = PCI_EXT_CAP_VER(header); + next = PCI_EXT_CAP_NEXT(header); + + /* + * If it becomes important to configure extended capabilities to their + * actual size, use this as the default when it's something we don't + * recognize. Since QEMU doesn't actually handle many of the config + * accesses, exact size doesn't seem worthwhile. + */ + size = vfio_ext_cap_max_size(config, pos); + + pcie_add_capability(pdev, cap_id, cap_ver, pos, size); + if (pos == PCI_CONFIG_SPACE_SIZE) { + /* Begin the rebuild, we should set the next offset zero. */ + pci_set_long(pdev->config + pos, PCI_EXT_CAP(cap_id, cap_ver, 0)); + } + + /* Use emulated header pointer to allow dropping extended caps */ + pci_set_long(vdev->emulated_config_bits + pos, 0xffffffff); + + if (next) { + ret = vfio_add_ext_cap(vdev, config, next); + if (ret) { + return ret; + } + } + + return 0; +} + static int vfio_add_capabilities(VFIOPCIDevice *vdev) { PCIDevice *pdev = &vdev->pdev; + int ret; + uint8_t *config; if (!(pdev->config[PCI_STATUS] & PCI_STATUS_CAP_LIST) || !pdev->config[PCI_CAPABILITY_LIST]) { return 0; /* Nothing to add */ } - return vfio_add_std_cap(vdev, pdev->config[PCI_CAPABILITY_LIST]); + ret = vfio_add_std_cap(vdev, pdev->config[PCI_CAPABILITY_LIST]); + if (ret) { + return ret; + } + + /* on PCI bus, it doesn't make sense to expose extended capabilities. */ + if (!pci_bus_is_express(vdev->pdev.bus) || + !pci_get_long(pdev->config + PCI_CONFIG_SPACE_SIZE)) { + return 0; + } + + /* + * In order to avoid config space broken, here using a copy config to + * parse extended capabilitiess. + */ + config = g_malloc0(vdev->config_size); + if (!config) { + return -ENOMEM; + } + memcpy(config, pdev->config, vdev->config_size); + ret = vfio_add_ext_cap(vdev, config, PCI_CONFIG_SPACE_SIZE); + + g_free(config); + return ret; } static void vfio_pci_pre_reset(VFIOPCIDevice *vdev) -- 1.9.3
