On Tue, 31 Dec 2024 23:19:52 +0800
Tomita Moeko <tomitamo...@gmail.com> wrote:
> Device may only expose a specific portion of PCI config space through a
> region in a BAR, such behavior is seen in igd GGC and BDSM mirrors in
> BAR0. To handle these, config_offset is introduced to allow mirroring
> arbitrary region in PCI config space.
>
> Signed-off-by: Tomita Moeko <tomitamo...@gmail.com>
> ---
> hw/vfio/pci-quirks.c | 5 +++++
> hw/vfio/pci-quirks.h | 3 ++-
> 2 files changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/hw/vfio/pci-quirks.c b/hw/vfio/pci-quirks.c
> index bb2ce1d904..5a0b25a544 100644
> --- a/hw/vfio/pci-quirks.c
> +++ b/hw/vfio/pci-quirks.c
> @@ -162,6 +162,7 @@ static uint64_t vfio_generic_quirk_mirror_read(void
> *opaque,
> (void)vfio_region_read(&vdev->bars[mirror->bar].region,
> addr + mirror->offset, size);
>
> + addr += mirror->config_offset;
> data = vfio_pci_read_config(&vdev->pdev, addr, size);
> trace_vfio_quirk_generic_mirror_read(vdev->vbasedev.name,
> memory_region_name(mirror->mem),
> @@ -175,6 +176,7 @@ static void vfio_generic_quirk_mirror_write(void *opaque,
> hwaddr addr,
> VFIOConfigMirrorQuirk *mirror = opaque;
> VFIOPCIDevice *vdev = mirror->vdev;
>
> + addr += mirror->config_offset;
> vfio_pci_write_config(&vdev->pdev, addr, data, size);
> trace_vfio_quirk_generic_mirror_write(vdev->vbasedev.name,
> memory_region_name(mirror->mem),
> @@ -456,6 +458,7 @@ static void vfio_probe_ati_bar2_quirk(VFIOPCIDevice
> *vdev, int nr)
> mirror->mem = quirk->mem;
> mirror->vdev = vdev;
> mirror->offset = 0x4000;
> + mirror->config_offset = 0;
These are all allocated with g_malloc0(), we don't need to explicitly
initialize this field in any of these existing uses. Thanks,
Alex
> mirror->bar = nr;
>
> memory_region_init_io(mirror->mem, OBJECT(vdev),
> @@ -908,6 +911,7 @@ static void vfio_probe_nvidia_bar0_quirk(VFIOPCIDevice
> *vdev, int nr)
> mirror->mem = quirk->mem;
> mirror->vdev = vdev;
> mirror->offset = 0x88000;
> + mirror->config_offset = 0;
> mirror->bar = nr;
> last = (LastDataSet *)&mirror->data;
> last->quirk = quirk;
> @@ -929,6 +933,7 @@ static void vfio_probe_nvidia_bar0_quirk(VFIOPCIDevice
> *vdev, int nr)
> mirror->mem = quirk->mem;
> mirror->vdev = vdev;
> mirror->offset = 0x1800;
> + mirror->config_offset = 0;
> mirror->bar = nr;
> last = (LastDataSet *)&mirror->data;
> last->quirk = quirk;
> diff --git a/hw/vfio/pci-quirks.h b/hw/vfio/pci-quirks.h
> index c0e96a01cc..d1532e379b 100644
> --- a/hw/vfio/pci-quirks.h
> +++ b/hw/vfio/pci-quirks.h
> @@ -60,7 +60,8 @@ extern const MemoryRegionOps vfio_generic_window_data_quirk;
> */
> typedef struct VFIOConfigMirrorQuirk {
> struct VFIOPCIDevice *vdev;
> - uint32_t offset;
> + uint32_t offset; /* Offset in BAR */
> + uint32_t config_offset; /* Offset in PCI config space */
> uint8_t bar;
> MemoryRegion *mem;
> uint8_t data[];
