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