From a574b0614449760a83310226b548e21b08a805fa Mon Sep 17 00:00:00 2001 From: John Levon Date: Fri, 6 Jun 2025 17:10:36 -0700 Subject: [PATCH] vfio: mark posted writes in region write callbacks MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit For vfio-user, the region write implementation needs to know if the write is posted; add the necessary plumbing to support this. Signed-off-by: John Levon Reviewed-by: Cédric Le Goater Link: https://lore.kernel.org/qemu-devel/20250607001056.335310-5-john.levon@nutanix.com Signed-off-by: Cédric Le Goater --- hw/vfio/device.c | 3 ++- hw/vfio/pci.c | 5 ++++- hw/vfio/region.c | 3 ++- include/hw/vfio/vfio-device.h | 4 ++-- include/hw/vfio/vfio-region.h | 1 + 5 files changed, 11 insertions(+), 5 deletions(-) diff --git a/hw/vfio/device.c b/hw/vfio/device.c index a4bdde8e8b..d32600eda1 100644 --- a/hw/vfio/device.c +++ b/hw/vfio/device.c @@ -543,7 +543,8 @@ static int vfio_device_io_region_read(VFIODevice *vbasedev, uint8_t index, } static int vfio_device_io_region_write(VFIODevice *vbasedev, uint8_t index, - off_t off, uint32_t size, void *data) + off_t off, uint32_t size, void *data, + bool post) { struct vfio_region_info *info; int ret; diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index 2901cedf6f..89f9246416 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -989,7 +989,7 @@ static int vfio_pci_config_space_write(VFIOPCIDevice *vdev, off_t offset, { return vdev->vbasedev.io_ops->region_write(&vdev->vbasedev, VFIO_PCI_CONFIG_REGION_INDEX, - offset, size, data); + offset, size, data, false); } static uint64_t vfio_rom_read(void *opaque, hwaddr addr, unsigned size) @@ -1793,6 +1793,9 @@ static void vfio_bar_prepare(VFIOPCIDevice *vdev, int nr) bar->type = pci_bar & (bar->ioport ? ~PCI_BASE_ADDRESS_IO_MASK : ~PCI_BASE_ADDRESS_MEM_MASK); bar->size = bar->region.size; + + /* IO regions are sync, memory can be async */ + bar->region.post_wr = (bar->ioport == 0); } static void vfio_bars_prepare(VFIOPCIDevice *vdev) diff --git a/hw/vfio/region.c b/hw/vfio/region.c index cb172f2136..f5b8e3cbf1 100644 --- a/hw/vfio/region.c +++ b/hw/vfio/region.c @@ -66,7 +66,7 @@ void vfio_region_write(void *opaque, hwaddr addr, } ret = vbasedev->io_ops->region_write(vbasedev, region->nr, - addr, size, &buf); + addr, size, &buf, region->post_wr); if (ret != size) { error_report("%s(%s:region%d+0x%"HWADDR_PRIx", 0x%"PRIx64 ",%d) failed: %s", @@ -200,6 +200,7 @@ int vfio_region_setup(Object *obj, VFIODevice *vbasedev, VFIORegion *region, region->size = info->size; region->fd_offset = info->offset; region->nr = index; + region->post_wr = false; if (region->size) { region->mem = g_new0(MemoryRegion, 1); diff --git a/include/hw/vfio/vfio-device.h b/include/hw/vfio/vfio-device.h index bf54fc6920..9793b2dba0 100644 --- a/include/hw/vfio/vfio-device.h +++ b/include/hw/vfio/vfio-device.h @@ -205,10 +205,10 @@ struct VFIODeviceIOOps { * @region_write * * Write @size bytes to the region @nr at offset @off from the buffer - * @data. + * @data; if @post, the write is posted. */ int (*region_write)(VFIODevice *vdev, uint8_t nr, off_t off, uint32_t size, - void *data); + void *data, bool post); }; void vfio_device_prepare(VFIODevice *vbasedev, VFIOContainerBase *bcontainer, diff --git a/include/hw/vfio/vfio-region.h b/include/hw/vfio/vfio-region.h index cbffb26962..ede6e0c8f9 100644 --- a/include/hw/vfio/vfio-region.h +++ b/include/hw/vfio/vfio-region.h @@ -29,6 +29,7 @@ typedef struct VFIORegion { uint32_t nr_mmaps; VFIOMmap *mmaps; uint8_t nr; /* cache the region number for debug */ + bool post_wr; /* writes can be posted */ } VFIORegion; -- 2.39.5