diff options
| -rw-r--r-- | hw/vfio_pci.c | 80 |
1 files changed, 42 insertions, 38 deletions
diff --git a/hw/vfio_pci.c b/hw/vfio_pci.c index 288361d0fb..a3bae7bd7a 100644 --- a/hw/vfio_pci.c +++ b/hw/vfio_pci.c @@ -117,6 +117,7 @@ typedef struct VFIODevice { int fd; VFIOINTx intx; unsigned int config_size; + uint8_t *emulated_config_bits; /* QEMU emulated bits, little-endian */ off_t config_offset; /* Offset of config space region within device fd */ unsigned int rom_size; off_t rom_offset; /* Offset of ROM region within device fd */ @@ -963,44 +964,29 @@ static const MemoryRegionOps vfio_bar_ops = { static uint32_t vfio_pci_read_config(PCIDevice *pdev, uint32_t addr, int len) { VFIODevice *vdev = DO_UPCAST(VFIODevice, pdev, pdev); - uint32_t val = 0; + uint32_t emu_bits = 0, emu_val = 0, phys_val = 0, val; - /* - * We only need QEMU PCI config support for the ROM BAR, the MSI and MSIX - * capabilities, and the multifunction bit below. We let VFIO handle - * virtualizing everything else. Performance is not a concern here. - */ - if (ranges_overlap(addr, len, PCI_ROM_ADDRESS, 4) || - (pdev->cap_present & QEMU_PCI_CAP_MSIX && - ranges_overlap(addr, len, pdev->msix_cap, MSIX_CAP_LENGTH)) || - (pdev->cap_present & QEMU_PCI_CAP_MSI && - ranges_overlap(addr, len, pdev->msi_cap, vdev->msi_cap_size))) { + memcpy(&emu_bits, vdev->emulated_config_bits + addr, len); + emu_bits = le32_to_cpu(emu_bits); - val = pci_default_read_config(pdev, addr, len); - } else { - if (pread(vdev->fd, &val, len, vdev->config_offset + addr) != len) { + if (emu_bits) { + emu_val = pci_default_read_config(pdev, addr, len); + } + + if (~emu_bits & (0xffffffffU >> (32 - len * 8))) { + ssize_t ret; + + ret = pread(vdev->fd, &phys_val, len, vdev->config_offset + addr); + if (ret != len) { error_report("%s(%04x:%02x:%02x.%x, 0x%x, 0x%x) failed: %m", __func__, vdev->host.domain, vdev->host.bus, vdev->host.slot, vdev->host.function, addr, len); return -errno; } - val = le32_to_cpu(val); + phys_val = le32_to_cpu(phys_val); } - /* Multifunction bit is virualized in QEMU */ - if (unlikely(ranges_overlap(addr, len, PCI_HEADER_TYPE, 1))) { - uint32_t mask = PCI_HEADER_TYPE_MULTI_FUNCTION; - - if (len == 4) { - mask <<= 16; - } - - if (pdev->cap_present & QEMU_PCI_CAP_MULTIFUNCTION) { - val |= mask; - } else { - val &= ~mask; - } - } + val = (emu_val & emu_bits) | (phys_val & ~emu_bits); DPRINTF("%s(%04x:%02x:%02x.%x, @0x%x, len=0x%x) %x\n", __func__, vdev->host.domain, vdev->host.bus, vdev->host.slot, @@ -1026,12 +1012,6 @@ static void vfio_pci_write_config(PCIDevice *pdev, uint32_t addr, vdev->host.slot, vdev->host.function, addr, val, len); } - /* Write standard header bits to emulation */ - if (addr < PCI_CONFIG_HEADER_SIZE) { - pci_default_write_config(pdev, addr, val, len); - return; - } - /* MSI/MSI-X Enabling/Disabling */ if (pdev->cap_present & QEMU_PCI_CAP_MSI && ranges_overlap(addr, len, pdev->msi_cap, vdev->msi_cap_size)) { @@ -1046,9 +1026,7 @@ static void vfio_pci_write_config(PCIDevice *pdev, uint32_t addr, } else if (was_enabled && !is_enabled) { vfio_disable_msi(vdev); } - } - - if (pdev->cap_present & QEMU_PCI_CAP_MSIX && + } else if (pdev->cap_present & QEMU_PCI_CAP_MSIX && ranges_overlap(addr, len, pdev->msix_cap, MSIX_CAP_LENGTH)) { int is_enabled, was_enabled = msix_enabled(pdev); @@ -1061,6 +1039,9 @@ static void vfio_pci_write_config(PCIDevice *pdev, uint32_t addr, } else if (was_enabled && !is_enabled) { vfio_disable_msix(vdev); } + } else { + /* Write everything to QEMU to keep emulated bits correct */ + pci_default_write_config(pdev, addr, val, len); } } @@ -2003,6 +1984,16 @@ static int vfio_initfn(PCIDevice *pdev) goto out_put; } + /* vfio emulates a lot for us, but some bits need extra love */ + vdev->emulated_config_bits = g_malloc0(vdev->config_size); + + /* QEMU can choose to expose the ROM or not */ + memset(vdev->emulated_config_bits + PCI_ROM_ADDRESS, 0xff, 4); + + /* QEMU can change multi-function devices to single function, or reverse */ + vdev->emulated_config_bits[PCI_HEADER_TYPE] = + PCI_HEADER_TYPE_MULTI_FUNCTION; + /* * Clear host resource mapping info. If we choose not to register a * BAR, such as might be the case with the option ROM, we can get @@ -2025,6 +2016,17 @@ static int vfio_initfn(PCIDevice *pdev) goto out_teardown; } + /* QEMU emulates all of MSI & MSIX */ + if (pdev->cap_present & QEMU_PCI_CAP_MSIX) { + memset(vdev->emulated_config_bits + pdev->msix_cap, 0xff, + MSIX_CAP_LENGTH); + } + + if (pdev->cap_present & QEMU_PCI_CAP_MSI) { + memset(vdev->emulated_config_bits + pdev->msi_cap, 0xff, + vdev->msi_cap_size); + } + if (vfio_pci_read_config(&vdev->pdev, PCI_INTERRUPT_PIN, 1)) { vdev->intx.mmap_timer = qemu_new_timer_ms(vm_clock, vfio_intx_mmap_enable, vdev); @@ -2042,6 +2044,7 @@ out_teardown: vfio_teardown_msi(vdev); vfio_unmap_bars(vdev); out_put: + g_free(vdev->emulated_config_bits); vfio_put_device(vdev); vfio_put_group(group); return ret; @@ -2059,6 +2062,7 @@ static void vfio_exitfn(PCIDevice *pdev) } vfio_teardown_msi(vdev); vfio_unmap_bars(vdev); + g_free(vdev->emulated_config_bits); vfio_put_device(vdev); vfio_put_group(group); } |