From 325ae8d548ebeee99cbebd38e2ff0909a9081c50 Mon Sep 17 00:00:00 2001 From: Chen Fan Date: Thu, 30 Jun 2016 13:00:23 -0600 Subject: [PATCH] vfio: add pcie extended capability support For vfio pcie device, we could expose the extended capability on PCIE bus. due to add a new pcie capability at the tail of the chain, in order to avoid config space overwritten, we introduce a copy config for parsing extended caps. and rebuild the pcie extended config space. Signed-off-by: Chen Fan Tested-by: Laszlo Ersek Signed-off-by: Alex Williamson --- hw/vfio/pci.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 71 insertions(+), 1 deletion(-) diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index 53b87b76ea04..a171056b41de 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -1502,6 +1502,21 @@ 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; + + 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); @@ -1749,16 +1764,71 @@ static int vfio_add_std_cap(VFIOPCIDevice *vdev, uint8_t pos) return 0; } +static int vfio_add_ext_cap(VFIOPCIDevice *vdev) +{ + PCIDevice *pdev = &vdev->pdev; + uint32_t header; + uint16_t cap_id, next, size; + uint8_t cap_ver; + uint8_t *config; + + /* + * pcie_add_capability always inserts the new capability at the tail + * of the chain. Therefore to end up with a chain that matches the + * physical device, we cache the config space to avoid overwriting + * the original config space when we parse the extended capabilities. + */ + config = g_memdup(pdev->config, vdev->config_size); + + for (next = PCI_CONFIG_SPACE_SIZE; next; + next = PCI_EXT_CAP_NEXT(pci_get_long(config + next))) { + header = pci_get_long(config + next); + cap_id = PCI_EXT_CAP_ID(header); + cap_ver = PCI_EXT_CAP_VER(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, next); + + pcie_add_capability(pdev, cap_id, cap_ver, next, size); + pci_set_long(pdev->config + next, PCI_EXT_CAP(cap_id, cap_ver, 0)); + + /* Use emulated next pointer to allow dropping extended caps */ + pci_long_test_and_set_mask(vdev->emulated_config_bits + next, + PCI_EXT_CAP_NEXT_MASK); + } + + g_free(config); + return 0; +} + static int vfio_add_capabilities(VFIOPCIDevice *vdev) { PCIDevice *pdev = &vdev->pdev; + int ret; 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_is_express(pdev) || + !pci_bus_is_express(pdev->bus) || + !pci_get_long(pdev->config + PCI_CONFIG_SPACE_SIZE)) { + return 0; + } + + return vfio_add_ext_cap(vdev); } static void vfio_pci_pre_reset(VFIOPCIDevice *vdev)