1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2015 MediaTek Inc. 4 */ 5 6 #include <linux/dma-buf.h> 7 8 #include <drm/drm.h> 9 #include <drm/drm_device.h> 10 #include <drm/drm_gem.h> 11 #include <drm/drm_gem_dma_helper.h> 12 #include <drm/drm_prime.h> 13 14 #include "mtk_drm_drv.h" 15 #include "mtk_drm_gem.h" 16 17 static int mtk_drm_gem_object_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma); 18 19 static const struct vm_operations_struct vm_ops = { 20 .open = drm_gem_vm_open, 21 .close = drm_gem_vm_close, 22 }; 23 24 static const struct drm_gem_object_funcs mtk_drm_gem_object_funcs = { 25 .free = mtk_drm_gem_free_object, 26 .get_sg_table = mtk_gem_prime_get_sg_table, 27 .vmap = mtk_drm_gem_prime_vmap, 28 .vunmap = mtk_drm_gem_prime_vunmap, 29 .mmap = mtk_drm_gem_object_mmap, 30 .vm_ops = &vm_ops, 31 }; 32 33 static struct mtk_drm_gem_obj *mtk_drm_gem_init(struct drm_device *dev, 34 unsigned long size) 35 { 36 struct mtk_drm_gem_obj *mtk_gem_obj; 37 int ret; 38 39 size = round_up(size, PAGE_SIZE); 40 41 if (size == 0) 42 return ERR_PTR(-EINVAL); 43 44 mtk_gem_obj = kzalloc(sizeof(*mtk_gem_obj), GFP_KERNEL); 45 if (!mtk_gem_obj) 46 return ERR_PTR(-ENOMEM); 47 48 mtk_gem_obj->base.funcs = &mtk_drm_gem_object_funcs; 49 50 ret = drm_gem_object_init(dev, &mtk_gem_obj->base, size); 51 if (ret < 0) { 52 DRM_ERROR("failed to initialize gem object\n"); 53 kfree(mtk_gem_obj); 54 return ERR_PTR(ret); 55 } 56 57 return mtk_gem_obj; 58 } 59 60 struct mtk_drm_gem_obj *mtk_drm_gem_create(struct drm_device *dev, 61 size_t size, bool alloc_kmap) 62 { 63 struct mtk_drm_private *priv = dev->dev_private; 64 struct mtk_drm_gem_obj *mtk_gem; 65 struct drm_gem_object *obj; 66 int ret; 67 68 mtk_gem = mtk_drm_gem_init(dev, size); 69 if (IS_ERR(mtk_gem)) 70 return ERR_CAST(mtk_gem); 71 72 obj = &mtk_gem->base; 73 74 mtk_gem->dma_attrs = DMA_ATTR_WRITE_COMBINE; 75 76 if (!alloc_kmap) 77 mtk_gem->dma_attrs |= DMA_ATTR_NO_KERNEL_MAPPING; 78 79 mtk_gem->cookie = dma_alloc_attrs(priv->dma_dev, obj->size, 80 &mtk_gem->dma_addr, GFP_KERNEL, 81 mtk_gem->dma_attrs); 82 if (!mtk_gem->cookie) { 83 DRM_ERROR("failed to allocate %zx byte dma buffer", obj->size); 84 ret = -ENOMEM; 85 goto err_gem_free; 86 } 87 88 if (alloc_kmap) 89 mtk_gem->kvaddr = mtk_gem->cookie; 90 91 DRM_DEBUG_DRIVER("cookie = %p dma_addr = %pad size = %zu\n", 92 mtk_gem->cookie, &mtk_gem->dma_addr, 93 size); 94 95 return mtk_gem; 96 97 err_gem_free: 98 drm_gem_object_release(obj); 99 kfree(mtk_gem); 100 return ERR_PTR(ret); 101 } 102 103 void mtk_drm_gem_free_object(struct drm_gem_object *obj) 104 { 105 struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj); 106 struct mtk_drm_private *priv = obj->dev->dev_private; 107 108 if (mtk_gem->sg) 109 drm_prime_gem_destroy(obj, mtk_gem->sg); 110 else 111 dma_free_attrs(priv->dma_dev, obj->size, mtk_gem->cookie, 112 mtk_gem->dma_addr, mtk_gem->dma_attrs); 113 114 /* release file pointer to gem object. */ 115 drm_gem_object_release(obj); 116 117 kfree(mtk_gem); 118 } 119 120 int mtk_drm_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev, 121 struct drm_mode_create_dumb *args) 122 { 123 struct mtk_drm_gem_obj *mtk_gem; 124 int ret; 125 126 args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8); 127 128 /* 129 * Multiply 2 variables of different types, 130 * for example: args->size = args->spacing * args->height; 131 * may cause coverity issue with unintentional overflow. 132 */ 133 args->size = args->pitch; 134 args->size *= args->height; 135 136 mtk_gem = mtk_drm_gem_create(dev, args->size, false); 137 if (IS_ERR(mtk_gem)) 138 return PTR_ERR(mtk_gem); 139 140 /* 141 * allocate a id of idr table where the obj is registered 142 * and handle has the id what user can see. 143 */ 144 ret = drm_gem_handle_create(file_priv, &mtk_gem->base, &args->handle); 145 if (ret) 146 goto err_handle_create; 147 148 /* drop reference from allocate - handle holds it now. */ 149 drm_gem_object_put(&mtk_gem->base); 150 151 return 0; 152 153 err_handle_create: 154 mtk_drm_gem_free_object(&mtk_gem->base); 155 return ret; 156 } 157 158 static int mtk_drm_gem_object_mmap(struct drm_gem_object *obj, 159 struct vm_area_struct *vma) 160 161 { 162 int ret; 163 struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj); 164 struct mtk_drm_private *priv = obj->dev->dev_private; 165 166 /* 167 * Set vm_pgoff (used as a fake buffer offset by DRM) to 0 and map the 168 * whole buffer from the start. 169 */ 170 vma->vm_pgoff = 0; 171 172 /* 173 * dma_alloc_attrs() allocated a struct page table for mtk_gem, so clear 174 * VM_PFNMAP flag that was set by drm_gem_mmap_obj()/drm_gem_mmap(). 175 */ 176 vm_flags_set(vma, VM_IO | VM_DONTEXPAND | VM_DONTDUMP); 177 vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); 178 vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot); 179 180 ret = dma_mmap_attrs(priv->dma_dev, vma, mtk_gem->cookie, 181 mtk_gem->dma_addr, obj->size, mtk_gem->dma_attrs); 182 183 return ret; 184 } 185 186 /* 187 * Allocate a sg_table for this GEM object. 188 * Note: Both the table's contents, and the sg_table itself must be freed by 189 * the caller. 190 * Returns a pointer to the newly allocated sg_table, or an ERR_PTR() error. 191 */ 192 struct sg_table *mtk_gem_prime_get_sg_table(struct drm_gem_object *obj) 193 { 194 struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj); 195 struct mtk_drm_private *priv = obj->dev->dev_private; 196 struct sg_table *sgt; 197 int ret; 198 199 sgt = kzalloc(sizeof(*sgt), GFP_KERNEL); 200 if (!sgt) 201 return ERR_PTR(-ENOMEM); 202 203 ret = dma_get_sgtable_attrs(priv->dma_dev, sgt, mtk_gem->cookie, 204 mtk_gem->dma_addr, obj->size, 205 mtk_gem->dma_attrs); 206 if (ret) { 207 DRM_ERROR("failed to allocate sgt, %d\n", ret); 208 kfree(sgt); 209 return ERR_PTR(ret); 210 } 211 212 return sgt; 213 } 214 215 struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev, 216 struct dma_buf_attachment *attach, struct sg_table *sg) 217 { 218 struct mtk_drm_gem_obj *mtk_gem; 219 220 /* check if the entries in the sg_table are contiguous */ 221 if (drm_prime_get_contiguous_size(sg) < attach->dmabuf->size) { 222 DRM_ERROR("sg_table is not contiguous"); 223 return ERR_PTR(-EINVAL); 224 } 225 226 mtk_gem = mtk_drm_gem_init(dev, attach->dmabuf->size); 227 if (IS_ERR(mtk_gem)) 228 return ERR_CAST(mtk_gem); 229 230 mtk_gem->dma_addr = sg_dma_address(sg->sgl); 231 mtk_gem->sg = sg; 232 233 return &mtk_gem->base; 234 } 235 236 int mtk_drm_gem_prime_vmap(struct drm_gem_object *obj, struct iosys_map *map) 237 { 238 struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj); 239 struct sg_table *sgt = NULL; 240 unsigned int npages; 241 242 if (mtk_gem->kvaddr) 243 goto out; 244 245 sgt = mtk_gem_prime_get_sg_table(obj); 246 if (IS_ERR(sgt)) 247 return PTR_ERR(sgt); 248 249 npages = obj->size >> PAGE_SHIFT; 250 mtk_gem->pages = kcalloc(npages, sizeof(*mtk_gem->pages), GFP_KERNEL); 251 if (!mtk_gem->pages) { 252 sg_free_table(sgt); 253 kfree(sgt); 254 return -ENOMEM; 255 } 256 257 drm_prime_sg_to_page_array(sgt, mtk_gem->pages, npages); 258 259 mtk_gem->kvaddr = vmap(mtk_gem->pages, npages, VM_MAP, 260 pgprot_writecombine(PAGE_KERNEL)); 261 if (!mtk_gem->kvaddr) { 262 sg_free_table(sgt); 263 kfree(sgt); 264 kfree(mtk_gem->pages); 265 return -ENOMEM; 266 } 267 sg_free_table(sgt); 268 kfree(sgt); 269 270 out: 271 iosys_map_set_vaddr(map, mtk_gem->kvaddr); 272 273 return 0; 274 } 275 276 void mtk_drm_gem_prime_vunmap(struct drm_gem_object *obj, 277 struct iosys_map *map) 278 { 279 struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj); 280 void *vaddr = map->vaddr; 281 282 if (!mtk_gem->pages) 283 return; 284 285 vunmap(vaddr); 286 mtk_gem->kvaddr = NULL; 287 kfree(mtk_gem->pages); 288 } 289