1 // SPDX-License-Identifier: GPL-2.0+ 2 /* Copyright (C) 2015-2018 Broadcom */ 3 4 /** 5 * DOC: V3D GEM BO management support 6 * 7 * Compared to VC4 (V3D 2.x), V3D 3.3 introduces an MMU between the 8 * GPU and the bus, allowing us to use shmem objects for our storage 9 * instead of CMA. 10 * 11 * Physically contiguous objects may still be imported to V3D, but the 12 * driver doesn't allocate physically contiguous objects on its own. 13 * Display engines requiring physically contiguous allocations should 14 * look into Mesa's "renderonly" support (as used by the Mesa pl111 15 * driver) for an example of how to integrate with V3D. 16 * 17 * Long term, we should support evicting pages from the MMU when under 18 * memory pressure (thus the v3d_bo_get_pages() refcounting), but 19 * that's not a high priority since our systems tend to not have swap. 20 */ 21 22 #include <linux/dma-buf.h> 23 #include <linux/pfn_t.h> 24 25 #include "v3d_drv.h" 26 #include "uapi/drm/v3d_drm.h" 27 28 /* Called DRM core on the last userspace/kernel unreference of the 29 * BO. 30 */ 31 void v3d_free_object(struct drm_gem_object *obj) 32 { 33 struct v3d_dev *v3d = to_v3d_dev(obj->dev); 34 struct v3d_bo *bo = to_v3d_bo(obj); 35 36 v3d_mmu_remove_ptes(bo); 37 38 mutex_lock(&v3d->bo_lock); 39 v3d->bo_stats.num_allocated--; 40 v3d->bo_stats.pages_allocated -= obj->size >> PAGE_SHIFT; 41 mutex_unlock(&v3d->bo_lock); 42 43 spin_lock(&v3d->mm_lock); 44 drm_mm_remove_node(&bo->node); 45 spin_unlock(&v3d->mm_lock); 46 47 /* GPU execution may have dirtied any pages in the BO. */ 48 bo->base.pages_mark_dirty_on_put = true; 49 50 drm_gem_shmem_free(&bo->base); 51 } 52 53 static const struct drm_gem_object_funcs v3d_gem_funcs = { 54 .free = v3d_free_object, 55 .print_info = drm_gem_shmem_object_print_info, 56 .pin = drm_gem_shmem_object_pin, 57 .unpin = drm_gem_shmem_object_unpin, 58 .get_sg_table = drm_gem_shmem_object_get_sg_table, 59 .vmap = drm_gem_shmem_object_vmap, 60 .vunmap = drm_gem_shmem_object_vunmap, 61 .mmap = drm_gem_shmem_object_mmap, 62 .vm_ops = &drm_gem_shmem_vm_ops, 63 }; 64 65 /* gem_create_object function for allocating a BO struct and doing 66 * early setup. 67 */ 68 struct drm_gem_object *v3d_create_object(struct drm_device *dev, size_t size) 69 { 70 struct v3d_bo *bo; 71 struct drm_gem_object *obj; 72 73 if (size == 0) 74 return ERR_PTR(-EINVAL); 75 76 bo = kzalloc(sizeof(*bo), GFP_KERNEL); 77 if (!bo) 78 return ERR_PTR(-ENOMEM); 79 obj = &bo->base.base; 80 81 obj->funcs = &v3d_gem_funcs; 82 bo->base.map_wc = true; 83 INIT_LIST_HEAD(&bo->unref_head); 84 85 return &bo->base.base; 86 } 87 88 static int 89 v3d_bo_create_finish(struct drm_gem_object *obj) 90 { 91 struct v3d_dev *v3d = to_v3d_dev(obj->dev); 92 struct v3d_bo *bo = to_v3d_bo(obj); 93 struct sg_table *sgt; 94 int ret; 95 96 /* So far we pin the BO in the MMU for its lifetime, so use 97 * shmem's helper for getting a lifetime sgt. 98 */ 99 sgt = drm_gem_shmem_get_pages_sgt(&bo->base); 100 if (IS_ERR(sgt)) 101 return PTR_ERR(sgt); 102 103 spin_lock(&v3d->mm_lock); 104 /* Allocate the object's space in the GPU's page tables. 105 * Inserting PTEs will happen later, but the offset is for the 106 * lifetime of the BO. 107 */ 108 ret = drm_mm_insert_node_generic(&v3d->mm, &bo->node, 109 obj->size >> PAGE_SHIFT, 110 GMP_GRANULARITY >> PAGE_SHIFT, 0, 0); 111 spin_unlock(&v3d->mm_lock); 112 if (ret) 113 return ret; 114 115 /* Track stats for /debug/dri/n/bo_stats. */ 116 mutex_lock(&v3d->bo_lock); 117 v3d->bo_stats.num_allocated++; 118 v3d->bo_stats.pages_allocated += obj->size >> PAGE_SHIFT; 119 mutex_unlock(&v3d->bo_lock); 120 121 v3d_mmu_insert_ptes(bo); 122 123 return 0; 124 } 125 126 struct v3d_bo *v3d_bo_create(struct drm_device *dev, struct drm_file *file_priv, 127 size_t unaligned_size) 128 { 129 struct drm_gem_shmem_object *shmem_obj; 130 struct v3d_bo *bo; 131 int ret; 132 133 shmem_obj = drm_gem_shmem_create(dev, unaligned_size); 134 if (IS_ERR(shmem_obj)) 135 return ERR_CAST(shmem_obj); 136 bo = to_v3d_bo(&shmem_obj->base); 137 138 ret = v3d_bo_create_finish(&shmem_obj->base); 139 if (ret) 140 goto free_obj; 141 142 return bo; 143 144 free_obj: 145 drm_gem_shmem_free(shmem_obj); 146 return ERR_PTR(ret); 147 } 148 149 struct drm_gem_object * 150 v3d_prime_import_sg_table(struct drm_device *dev, 151 struct dma_buf_attachment *attach, 152 struct sg_table *sgt) 153 { 154 struct drm_gem_object *obj; 155 int ret; 156 157 obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt); 158 if (IS_ERR(obj)) 159 return obj; 160 161 ret = v3d_bo_create_finish(obj); 162 if (ret) { 163 drm_gem_shmem_free(&to_v3d_bo(obj)->base); 164 return ERR_PTR(ret); 165 } 166 167 return obj; 168 } 169 170 int v3d_create_bo_ioctl(struct drm_device *dev, void *data, 171 struct drm_file *file_priv) 172 { 173 struct drm_v3d_create_bo *args = data; 174 struct v3d_bo *bo = NULL; 175 int ret; 176 177 if (args->flags != 0) { 178 DRM_INFO("unknown create_bo flags: %d\n", args->flags); 179 return -EINVAL; 180 } 181 182 bo = v3d_bo_create(dev, file_priv, PAGE_ALIGN(args->size)); 183 if (IS_ERR(bo)) 184 return PTR_ERR(bo); 185 186 args->offset = bo->node.start << PAGE_SHIFT; 187 188 ret = drm_gem_handle_create(file_priv, &bo->base.base, &args->handle); 189 drm_gem_object_put(&bo->base.base); 190 191 return ret; 192 } 193 194 int v3d_mmap_bo_ioctl(struct drm_device *dev, void *data, 195 struct drm_file *file_priv) 196 { 197 struct drm_v3d_mmap_bo *args = data; 198 struct drm_gem_object *gem_obj; 199 200 if (args->flags != 0) { 201 DRM_INFO("unknown mmap_bo flags: %d\n", args->flags); 202 return -EINVAL; 203 } 204 205 gem_obj = drm_gem_object_lookup(file_priv, args->handle); 206 if (!gem_obj) { 207 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle); 208 return -ENOENT; 209 } 210 211 args->offset = drm_vma_node_offset_addr(&gem_obj->vma_node); 212 drm_gem_object_put(gem_obj); 213 214 return 0; 215 } 216 217 int v3d_get_bo_offset_ioctl(struct drm_device *dev, void *data, 218 struct drm_file *file_priv) 219 { 220 struct drm_v3d_get_bo_offset *args = data; 221 struct drm_gem_object *gem_obj; 222 struct v3d_bo *bo; 223 224 gem_obj = drm_gem_object_lookup(file_priv, args->handle); 225 if (!gem_obj) { 226 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle); 227 return -ENOENT; 228 } 229 bo = to_v3d_bo(gem_obj); 230 231 args->offset = bo->node.start << PAGE_SHIFT; 232 233 drm_gem_object_put(gem_obj); 234 return 0; 235 } 236