From cdc537ada9528e09f8c70219f5a9a1ce8a4efa7e Mon Sep 17 00:00:00 2001 From: Gerd Hoffmann Date: Thu, 6 May 2021 11:10:01 +0200 Subject: [PATCH 02/12] virtio-gpu: handle partial maps properly RH-Author: Eric Auger RH-MergeRequest: 15: virtio-gpu: handle partial maps properly RH-Commit: [1/1] f2b0fd9758251d1f3a5ff9563911c8bdb4b191f0 (eauger1/centos-qemu-kvm) RH-Bugzilla: 1974795 RH-Acked-by: Gavin Shan RH-Acked-by: Andrew Jones RH-Acked-by: Peter Xu dma_memory_map() may map only a part of the request. Happens if the request can't be mapped in one go, for example due to a iommu creating a linear dma mapping for scattered physical pages. Should that be the case virtio-gpu must call dma_memory_map() again with the remaining range instead of simply throwing an error. Note that this change implies the number of iov entries may differ from the number of mapping entries sent by the guest. Therefore the iov_len bookkeeping needs some updates too, we have to explicitly pass around the iov length now. Reported-by: Auger Eric Signed-off-by: Gerd Hoffmann Message-id: 20210506091001.1301250-1-kraxel@redhat.com Reviewed-by: Eric Auger Tested-by: Eric Auger Message-Id: <20210506091001.1301250-1-kraxel@redhat.com> (cherry picked from commit 9049f8bc445d50c0b5fe5500c0ec51fcc821c2ef) Signed-off-by: Eric Auger Signed-off-by: Miroslav Rezanina --- hw/display/virtio-gpu-3d.c | 7 ++-- hw/display/virtio-gpu.c | 76 ++++++++++++++++++++-------------- include/hw/virtio/virtio-gpu.h | 3 +- 3 files changed, 52 insertions(+), 34 deletions(-) diff --git a/hw/display/virtio-gpu-3d.c b/hw/display/virtio-gpu-3d.c index d98964858e..72c14d9132 100644 --- a/hw/display/virtio-gpu-3d.c +++ b/hw/display/virtio-gpu-3d.c @@ -283,22 +283,23 @@ static void virgl_resource_attach_backing(VirtIOGPU *g, { struct virtio_gpu_resource_attach_backing att_rb; struct iovec *res_iovs; + uint32_t res_niov; int ret; VIRTIO_GPU_FILL_CMD(att_rb); trace_virtio_gpu_cmd_res_back_attach(att_rb.resource_id); - ret = virtio_gpu_create_mapping_iov(g, &att_rb, cmd, NULL, &res_iovs); + ret = virtio_gpu_create_mapping_iov(g, &att_rb, cmd, NULL, &res_iovs, &res_niov); if (ret != 0) { cmd->error = VIRTIO_GPU_RESP_ERR_UNSPEC; return; } ret = virgl_renderer_resource_attach_iov(att_rb.resource_id, - res_iovs, att_rb.nr_entries); + res_iovs, res_niov); if (ret != 0) - virtio_gpu_cleanup_mapping_iov(g, res_iovs, att_rb.nr_entries); + virtio_gpu_cleanup_mapping_iov(g, res_iovs, res_niov); } static void virgl_resource_detach_backing(VirtIOGPU *g, diff --git a/hw/display/virtio-gpu.c b/hw/display/virtio-gpu.c index c9f5e36fd0..6f3791deb3 100644 --- a/hw/display/virtio-gpu.c +++ b/hw/display/virtio-gpu.c @@ -608,11 +608,12 @@ static void virtio_gpu_set_scanout(VirtIOGPU *g, int virtio_gpu_create_mapping_iov(VirtIOGPU *g, struct virtio_gpu_resource_attach_backing *ab, struct virtio_gpu_ctrl_command *cmd, - uint64_t **addr, struct iovec **iov) + uint64_t **addr, struct iovec **iov, + uint32_t *niov) { struct virtio_gpu_mem_entry *ents; size_t esize, s; - int i; + int e, v; if (ab->nr_entries > 16384) { qemu_log_mask(LOG_GUEST_ERROR, @@ -633,37 +634,53 @@ int virtio_gpu_create_mapping_iov(VirtIOGPU *g, return -1; } - *iov = g_malloc0(sizeof(struct iovec) * ab->nr_entries); + *iov = NULL; if (addr) { - *addr = g_malloc0(sizeof(uint64_t) * ab->nr_entries); + *addr = NULL; } - for (i = 0; i < ab->nr_entries; i++) { - uint64_t a = le64_to_cpu(ents[i].addr); - uint32_t l = le32_to_cpu(ents[i].length); - hwaddr len = l; - (*iov)[i].iov_base = dma_memory_map(VIRTIO_DEVICE(g)->dma_as, - a, &len, DMA_DIRECTION_TO_DEVICE); - (*iov)[i].iov_len = len; - if (addr) { - (*addr)[i] = a; - } - if (!(*iov)[i].iov_base || len != l) { - qemu_log_mask(LOG_GUEST_ERROR, "%s: failed to map MMIO memory for" - " resource %d element %d\n", - __func__, ab->resource_id, i); - if ((*iov)[i].iov_base) { - i++; /* cleanup the 'i'th map */ + for (e = 0, v = 0; e < ab->nr_entries; e++) { + uint64_t a = le64_to_cpu(ents[e].addr); + uint32_t l = le32_to_cpu(ents[e].length); + hwaddr len; + void *map; + + do { + len = l; + map = dma_memory_map(VIRTIO_DEVICE(g)->dma_as, + a, &len, DMA_DIRECTION_TO_DEVICE); + if (!map) { + qemu_log_mask(LOG_GUEST_ERROR, "%s: failed to map MMIO memory for" + " resource %d element %d\n", + __func__, ab->resource_id, e); + virtio_gpu_cleanup_mapping_iov(g, *iov, v); + g_free(ents); + *iov = NULL; + if (addr) { + g_free(*addr); + *addr = NULL; + } + return -1; + } + + if (!(v % 16)) { + *iov = g_realloc(*iov, sizeof(struct iovec) * (v + 16)); + if (addr) { + *addr = g_realloc(*addr, sizeof(uint64_t) * (v + 16)); + } } - virtio_gpu_cleanup_mapping_iov(g, *iov, i); - g_free(ents); - *iov = NULL; + (*iov)[v].iov_base = map; + (*iov)[v].iov_len = len; if (addr) { - g_free(*addr); - *addr = NULL; + (*addr)[v] = a; } - return -1; - } + + a += len; + l -= len; + v += 1; + } while (l > 0); } + *niov = v; + g_free(ents); return 0; } @@ -717,13 +734,12 @@ virtio_gpu_resource_attach_backing(VirtIOGPU *g, return; } - ret = virtio_gpu_create_mapping_iov(g, &ab, cmd, &res->addrs, &res->iov); + ret = virtio_gpu_create_mapping_iov(g, &ab, cmd, &res->addrs, + &res->iov, &res->iov_cnt); if (ret != 0) { cmd->error = VIRTIO_GPU_RESP_ERR_UNSPEC; return; } - - res->iov_cnt = ab.nr_entries; } static void diff --git a/include/hw/virtio/virtio-gpu.h b/include/hw/virtio/virtio-gpu.h index fae149235c..0d15af41d9 100644 --- a/include/hw/virtio/virtio-gpu.h +++ b/include/hw/virtio/virtio-gpu.h @@ -209,7 +209,8 @@ void virtio_gpu_get_edid(VirtIOGPU *g, int virtio_gpu_create_mapping_iov(VirtIOGPU *g, struct virtio_gpu_resource_attach_backing *ab, struct virtio_gpu_ctrl_command *cmd, - uint64_t **addr, struct iovec **iov); + uint64_t **addr, struct iovec **iov, + uint32_t *niov); void virtio_gpu_cleanup_mapping_iov(VirtIOGPU *g, struct iovec *iov, uint32_t count); void virtio_gpu_process_cmdq(VirtIOGPU *g); -- 2.27.0