drivers/gpu/drm/virtio/virtgpu_vram.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include "virtgpu_drv.h"
   3
   4 static void virtio_gpu_vram_free(struct drm_gem_object *obj)
   5 {
   6         struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);
   7         struct virtio_gpu_device *vgdev = obj->dev->dev_private;
   8         struct virtio_gpu_object_vram *vram = to_virtio_gpu_vram(bo);
   9         bool unmap;
  10
  11         if (bo->created) {
  12                 spin_lock(&vgdev->host_visible_lock);
  13                 unmap = drm_mm_node_allocated(&vram->vram_node);
  14                 spin_unlock(&vgdev->host_visible_lock);
  15
  16                 if (unmap)
  17                         virtio_gpu_cmd_unmap(vgdev, bo);
  18
  19                 virtio_gpu_cmd_unref_resource(vgdev, bo);
  20                 virtio_gpu_notify(vgdev);
  21                 return;
  22         }
  23 }
  24
  25 static const struct vm_operations_struct virtio_gpu_vram_vm_ops = {
  26         .open = drm_gem_vm_open,
  27         .close = drm_gem_vm_close,
  28 };
  29
  30 static int virtio_gpu_vram_mmap(struct drm_gem_object *obj,
  31                                 struct vm_area_struct *vma)
  32 {
  33         int ret;
  34         struct virtio_gpu_device *vgdev = obj->dev->dev_private;
  35         struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);
  36         struct virtio_gpu_object_vram *vram = to_virtio_gpu_vram(bo);
  37         unsigned long vm_size = vma->vm_end - vma->vm_start;
  38
  39         if (!(bo->blob_flags & VIRTGPU_BLOB_FLAG_USE_MAPPABLE))
  40                 return -EINVAL;
  41
  42         wait_event(vgdev->resp_wq, vram->map_state != STATE_INITIALIZING);
  43         if (vram->map_state != STATE_OK)
  44                 return -EINVAL;
  45
  46         vma->vm_pgoff -= drm_vma_node_start(&obj->vma_node);
  47         vma->vm_flags |= VM_MIXEDMAP | VM_DONTEXPAND;
  48         vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
  49         vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
  50         vma->vm_ops = &virtio_gpu_vram_vm_ops;
  51
  52         if (vram->map_info == VIRTIO_GPU_MAP_CACHE_WC)
  53                 vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
  54         else if (vram->map_info == VIRTIO_GPU_MAP_CACHE_UNCACHED)
  55                 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
  56
  57         /* Partial mappings of GEM buffers don't happen much in practice. */
  58         if (vm_size != vram->vram_node.size)
  59                 return -EINVAL;
  60
  61         ret = io_remap_pfn_range(vma, vma->vm_start,
  62                                  vram->vram_node.start >> PAGE_SHIFT,
  63                                  vm_size, vma->vm_page_prot);
  64         return ret;
  65 }
  66
  67 static const struct drm_gem_object_funcs virtio_gpu_vram_funcs = {
  68         .open = virtio_gpu_gem_object_open,
  69         .close = virtio_gpu_gem_object_close,
  70         .free = virtio_gpu_vram_free,
  71         .mmap = virtio_gpu_vram_mmap,
  72 };
  73
  74 bool virtio_gpu_is_vram(struct virtio_gpu_object *bo)
  75 {
  76         return bo->base.base.funcs == &virtio_gpu_vram_funcs;
  77 }
  78
  79 static int virtio_gpu_vram_map(struct virtio_gpu_object *bo)
  80 {
  81         int ret;
  82         uint64_t offset;
  83         struct virtio_gpu_object_array *objs;
  84         struct virtio_gpu_device *vgdev = bo->base.base.dev->dev_private;
  85         struct virtio_gpu_object_vram *vram = to_virtio_gpu_vram(bo);
  86
  87         if (!vgdev->has_host_visible)
  88                 return -EINVAL;
  89
  90         spin_lock(&vgdev->host_visible_lock);
  91         ret = drm_mm_insert_node(&vgdev->host_visible_mm, &vram->vram_node,
  92                                  bo->base.base.size);
  93         spin_unlock(&vgdev->host_visible_lock);
  94
  95         if (ret)
  96                 return ret;
  97
  98         objs = virtio_gpu_array_alloc(1);
  99         if (!objs) {
 100                 ret = -ENOMEM;
 101                 goto err_remove_node;
 102         }
 103
 104         virtio_gpu_array_add_obj(objs, &bo->base.base);
 105         /*TODO: Add an error checking helper function in drm_mm.h */
 106         offset = vram->vram_node.start - vgdev->host_visible_region.addr;
 107
 108         ret = virtio_gpu_cmd_map(vgdev, objs, offset);
 109         if (ret) {
 110                 virtio_gpu_array_put_free(objs);
 111                 goto err_remove_node;
 112         }
 113
 114         return 0;
 115
 116 err_remove_node:
 117         spin_lock(&vgdev->host_visible_lock);
 118         drm_mm_remove_node(&vram->vram_node);
 119         spin_unlock(&vgdev->host_visible_lock);
 120         return ret;
 121 }
 122
 123 int virtio_gpu_vram_create(struct virtio_gpu_device *vgdev,
 124                            struct virtio_gpu_object_params *params,
 125                            struct virtio_gpu_object **bo_ptr)
 126 {
 127         struct drm_gem_object *obj;
 128         struct virtio_gpu_object_vram *vram;
 129         int ret;
 130
 131         vram = kzalloc(sizeof(*vram), GFP_KERNEL);
 132         if (!vram)
 133                 return -ENOMEM;
 134
 135         obj = &vram->base.base.base;
 136         obj->funcs = &virtio_gpu_vram_funcs;
 137         drm_gem_private_object_init(vgdev->ddev, obj, params->size);
 138
 139         /* Create fake offset */
 140         ret = drm_gem_create_mmap_offset(obj);
 141         if (ret) {
 142                 kfree(vram);
 143                 return ret;
 144         }
 145
 146         ret = virtio_gpu_resource_id_get(vgdev, &vram->base.hw_res_handle);
 147         if (ret) {
 148                 kfree(vram);
 149                 return ret;
 150         }
 151
 152         virtio_gpu_cmd_resource_create_blob(vgdev, &vram->base, params, NULL,
 153                                             0);
 154         if (params->blob_flags & VIRTGPU_BLOB_FLAG_USE_MAPPABLE) {
 155                 ret = virtio_gpu_vram_map(&vram->base);
 156                 if (ret) {
 157                         virtio_gpu_vram_free(obj);
 158                         return ret;
 159                 }
 160         }
 161
 162         *bo_ptr = &vram->base;
 163         return 0;
 164 }