1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* exynos_drm_gem.c 3 * 4 * Copyright (c) 2011 Samsung Electronics Co., Ltd. 5 * Author: Inki Dae <inki.dae@samsung.com> 6 */ 7 8 9 #include <linux/dma-buf.h> 10 #include <linux/shmem_fs.h> 11 #include <linux/module.h> 12 13 #include <drm/drm_dumb_buffers.h> 14 #include <drm/drm_prime.h> 15 #include <drm/drm_print.h> 16 #include <drm/drm_vma_manager.h> 17 #include <drm/exynos_drm.h> 18 19 #include "exynos_drm_drv.h" 20 #include "exynos_drm_gem.h" 21 22 MODULE_IMPORT_NS("DMA_BUF"); 23 24 static int exynos_drm_gem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma); 25 26 static int exynos_drm_alloc_buf(struct exynos_drm_gem *exynos_gem, bool kvmap) 27 { 28 struct drm_device *dev = exynos_gem->base.dev; 29 unsigned long attr = 0; 30 31 if (exynos_gem->dma_addr) { 32 DRM_DEV_DEBUG_KMS(to_dma_dev(dev), "already allocated.\n"); 33 return 0; 34 } 35 36 /* 37 * if EXYNOS_BO_CONTIG, fully physically contiguous memory 38 * region will be allocated else physically contiguous 39 * as possible. 40 */ 41 if (!(exynos_gem->flags & EXYNOS_BO_NONCONTIG)) 42 attr |= DMA_ATTR_FORCE_CONTIGUOUS; 43 44 /* 45 * if EXYNOS_BO_WC or EXYNOS_BO_NONCACHABLE, writecombine mapping 46 * else cachable mapping. 47 */ 48 if (exynos_gem->flags & EXYNOS_BO_WC || 49 !(exynos_gem->flags & EXYNOS_BO_CACHABLE)) 50 attr |= DMA_ATTR_WRITE_COMBINE; 51 52 /* FBDev emulation requires kernel mapping */ 53 if (!kvmap) 54 attr |= DMA_ATTR_NO_KERNEL_MAPPING; 55 56 exynos_gem->dma_attrs = attr; 57 exynos_gem->cookie = dma_alloc_attrs(to_dma_dev(dev), exynos_gem->size, 58 &exynos_gem->dma_addr, GFP_KERNEL, 59 exynos_gem->dma_attrs); 60 if (!exynos_gem->cookie) { 61 DRM_DEV_ERROR(to_dma_dev(dev), "failed to allocate buffer.\n"); 62 return -ENOMEM; 63 } 64 65 if (kvmap) 66 exynos_gem->kvaddr = exynos_gem->cookie; 67 68 DRM_DEV_DEBUG_KMS(to_dma_dev(dev), "dma_addr(0x%lx), size(0x%lx)\n", 69 (unsigned long)exynos_gem->dma_addr, exynos_gem->size); 70 return 0; 71 } 72 73 static void exynos_drm_free_buf(struct exynos_drm_gem *exynos_gem) 74 { 75 struct drm_device *dev = exynos_gem->base.dev; 76 77 if (!exynos_gem->dma_addr) { 78 DRM_DEV_DEBUG_KMS(dev->dev, "dma_addr is invalid.\n"); 79 return; 80 } 81 82 DRM_DEV_DEBUG_KMS(dev->dev, "dma_addr(0x%lx), size(0x%lx)\n", 83 (unsigned long)exynos_gem->dma_addr, exynos_gem->size); 84 85 dma_free_attrs(to_dma_dev(dev), exynos_gem->size, exynos_gem->cookie, 86 (dma_addr_t)exynos_gem->dma_addr, 87 exynos_gem->dma_attrs); 88 } 89 90 static int exynos_drm_gem_handle_create(struct drm_gem_object *obj, 91 struct drm_file *file_priv, 92 unsigned int *handle) 93 { 94 int ret; 95 96 /* 97 * allocate a id of idr table where the obj is registered 98 * and handle has the id what user can see. 99 */ 100 ret = drm_gem_handle_create(file_priv, obj, handle); 101 if (ret) 102 return ret; 103 104 DRM_DEV_DEBUG_KMS(to_dma_dev(obj->dev), "gem handle = 0x%x\n", *handle); 105 106 /* drop reference from allocate - handle holds it now. */ 107 drm_gem_object_put(obj); 108 109 return 0; 110 } 111 112 void exynos_drm_gem_destroy(struct exynos_drm_gem *exynos_gem) 113 { 114 struct drm_gem_object *obj = &exynos_gem->base; 115 116 DRM_DEV_DEBUG_KMS(to_dma_dev(obj->dev), "handle count = %d\n", 117 obj->handle_count); 118 119 /* 120 * do not release memory region from exporter. 121 * 122 * the region will be released by exporter 123 * once dmabuf's refcount becomes 0. 124 */ 125 if (obj->import_attach) 126 drm_prime_gem_destroy(obj, exynos_gem->sgt); 127 else 128 exynos_drm_free_buf(exynos_gem); 129 130 /* release file pointer to gem object. */ 131 drm_gem_object_release(obj); 132 133 kfree(exynos_gem); 134 } 135 136 static const struct vm_operations_struct exynos_drm_gem_vm_ops = { 137 .open = drm_gem_vm_open, 138 .close = drm_gem_vm_close, 139 }; 140 141 static const struct drm_gem_object_funcs exynos_drm_gem_object_funcs = { 142 .free = exynos_drm_gem_free_object, 143 .get_sg_table = exynos_drm_gem_prime_get_sg_table, 144 .mmap = exynos_drm_gem_mmap, 145 .vm_ops = &exynos_drm_gem_vm_ops, 146 }; 147 148 static struct exynos_drm_gem *exynos_drm_gem_init(struct drm_device *dev, 149 unsigned long size) 150 { 151 struct exynos_drm_gem *exynos_gem; 152 struct drm_gem_object *obj; 153 int ret; 154 155 exynos_gem = kzalloc(sizeof(*exynos_gem), GFP_KERNEL); 156 if (!exynos_gem) 157 return ERR_PTR(-ENOMEM); 158 159 exynos_gem->size = size; 160 obj = &exynos_gem->base; 161 162 obj->funcs = &exynos_drm_gem_object_funcs; 163 164 ret = drm_gem_object_init(dev, obj, size); 165 if (ret < 0) { 166 DRM_DEV_ERROR(dev->dev, "failed to initialize gem object\n"); 167 kfree(exynos_gem); 168 return ERR_PTR(ret); 169 } 170 171 ret = drm_gem_create_mmap_offset(obj); 172 if (ret < 0) { 173 drm_gem_object_release(obj); 174 kfree(exynos_gem); 175 return ERR_PTR(ret); 176 } 177 178 DRM_DEV_DEBUG_KMS(dev->dev, "created file object = %p\n", obj->filp); 179 180 return exynos_gem; 181 } 182 183 struct exynos_drm_gem *exynos_drm_gem_create(struct drm_device *dev, 184 unsigned int flags, 185 unsigned long size, 186 bool kvmap) 187 { 188 struct exynos_drm_gem *exynos_gem; 189 int ret; 190 191 if (flags & ~(EXYNOS_BO_MASK)) { 192 DRM_DEV_ERROR(dev->dev, 193 "invalid GEM buffer flags: %u\n", flags); 194 return ERR_PTR(-EINVAL); 195 } 196 197 if (!size) { 198 DRM_DEV_ERROR(dev->dev, "invalid GEM buffer size: %lu\n", size); 199 return ERR_PTR(-EINVAL); 200 } 201 202 size = roundup(size, PAGE_SIZE); 203 204 exynos_gem = exynos_drm_gem_init(dev, size); 205 if (IS_ERR(exynos_gem)) 206 return exynos_gem; 207 208 if (!is_drm_iommu_supported(dev) && (flags & EXYNOS_BO_NONCONTIG)) { 209 /* 210 * when no IOMMU is available, all allocated buffers are 211 * contiguous anyway, so drop EXYNOS_BO_NONCONTIG flag 212 */ 213 flags &= ~EXYNOS_BO_NONCONTIG; 214 DRM_WARN("Non-contiguous allocation is not supported without IOMMU, falling back to contiguous buffer\n"); 215 } 216 217 /* set memory type and cache attribute from user side. */ 218 exynos_gem->flags = flags; 219 220 ret = exynos_drm_alloc_buf(exynos_gem, kvmap); 221 if (ret < 0) { 222 drm_gem_object_release(&exynos_gem->base); 223 kfree(exynos_gem); 224 return ERR_PTR(ret); 225 } 226 227 return exynos_gem; 228 } 229 230 int exynos_drm_gem_create_ioctl(struct drm_device *dev, void *data, 231 struct drm_file *file_priv) 232 { 233 struct drm_exynos_gem_create *args = data; 234 struct exynos_drm_gem *exynos_gem; 235 int ret; 236 237 exynos_gem = exynos_drm_gem_create(dev, args->flags, args->size, false); 238 if (IS_ERR(exynos_gem)) 239 return PTR_ERR(exynos_gem); 240 241 ret = exynos_drm_gem_handle_create(&exynos_gem->base, file_priv, 242 &args->handle); 243 if (ret) { 244 exynos_drm_gem_destroy(exynos_gem); 245 return ret; 246 } 247 248 return 0; 249 } 250 251 int exynos_drm_gem_map_ioctl(struct drm_device *dev, void *data, 252 struct drm_file *file_priv) 253 { 254 struct drm_exynos_gem_map *args = data; 255 256 return drm_gem_dumb_map_offset(file_priv, dev, args->handle, 257 &args->offset); 258 } 259 260 struct exynos_drm_gem *exynos_drm_gem_get(struct drm_file *filp, 261 unsigned int gem_handle) 262 { 263 struct drm_gem_object *obj; 264 265 obj = drm_gem_object_lookup(filp, gem_handle); 266 if (!obj) 267 return NULL; 268 return to_exynos_gem(obj); 269 } 270 271 static int exynos_drm_gem_mmap_buffer(struct exynos_drm_gem *exynos_gem, 272 struct vm_area_struct *vma) 273 { 274 struct drm_device *drm_dev = exynos_gem->base.dev; 275 unsigned long vm_size; 276 int ret; 277 278 vm_flags_clear(vma, VM_PFNMAP); 279 vma->vm_pgoff = 0; 280 281 vm_size = vma->vm_end - vma->vm_start; 282 283 /* check if user-requested size is valid. */ 284 if (vm_size > exynos_gem->size) 285 return -EINVAL; 286 287 ret = dma_mmap_attrs(to_dma_dev(drm_dev), vma, exynos_gem->cookie, 288 exynos_gem->dma_addr, exynos_gem->size, 289 exynos_gem->dma_attrs); 290 if (ret < 0) { 291 DRM_ERROR("failed to mmap.\n"); 292 return ret; 293 } 294 295 return 0; 296 } 297 298 int exynos_drm_gem_get_ioctl(struct drm_device *dev, void *data, 299 struct drm_file *file_priv) 300 { 301 struct exynos_drm_gem *exynos_gem; 302 struct drm_exynos_gem_info *args = data; 303 struct drm_gem_object *obj; 304 305 obj = drm_gem_object_lookup(file_priv, args->handle); 306 if (!obj) { 307 DRM_DEV_ERROR(dev->dev, "failed to lookup gem object.\n"); 308 return -EINVAL; 309 } 310 311 exynos_gem = to_exynos_gem(obj); 312 313 args->flags = exynos_gem->flags; 314 args->size = exynos_gem->size; 315 316 drm_gem_object_put(obj); 317 318 return 0; 319 } 320 321 void exynos_drm_gem_free_object(struct drm_gem_object *obj) 322 { 323 exynos_drm_gem_destroy(to_exynos_gem(obj)); 324 } 325 326 int exynos_drm_gem_dumb_create(struct drm_file *file_priv, 327 struct drm_device *dev, 328 struct drm_mode_create_dumb *args) 329 { 330 struct exynos_drm_gem *exynos_gem; 331 unsigned int flags; 332 int ret; 333 334 ret = drm_mode_size_dumb(dev, args, 0, 0); 335 if (ret) 336 return ret; 337 338 /* 339 * allocate memory to be used for framebuffer. 340 * - this callback would be called by user application 341 * with DRM_IOCTL_MODE_CREATE_DUMB command. 342 */ 343 344 if (is_drm_iommu_supported(dev)) 345 flags = EXYNOS_BO_NONCONTIG | EXYNOS_BO_WC; 346 else 347 flags = EXYNOS_BO_CONTIG | EXYNOS_BO_WC; 348 349 exynos_gem = exynos_drm_gem_create(dev, flags, args->size, false); 350 if (IS_ERR(exynos_gem)) { 351 dev_warn(dev->dev, "FB allocation failed.\n"); 352 return PTR_ERR(exynos_gem); 353 } 354 355 ret = exynos_drm_gem_handle_create(&exynos_gem->base, file_priv, 356 &args->handle); 357 if (ret) { 358 exynos_drm_gem_destroy(exynos_gem); 359 return ret; 360 } 361 362 return 0; 363 } 364 365 static int exynos_drm_gem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma) 366 { 367 struct exynos_drm_gem *exynos_gem = to_exynos_gem(obj); 368 int ret; 369 370 if (obj->import_attach) 371 return dma_buf_mmap(obj->dma_buf, vma, 0); 372 373 vm_flags_set(vma, VM_IO | VM_DONTEXPAND | VM_DONTDUMP); 374 375 DRM_DEV_DEBUG_KMS(to_dma_dev(obj->dev), "flags = 0x%x\n", 376 exynos_gem->flags); 377 378 /* non-cachable as default. */ 379 if (exynos_gem->flags & EXYNOS_BO_CACHABLE) 380 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); 381 else if (exynos_gem->flags & EXYNOS_BO_WC) 382 vma->vm_page_prot = 383 pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); 384 else 385 vma->vm_page_prot = 386 pgprot_noncached(vm_get_page_prot(vma->vm_flags)); 387 388 ret = exynos_drm_gem_mmap_buffer(exynos_gem, vma); 389 if (ret) 390 goto err_close_vm; 391 392 return ret; 393 394 err_close_vm: 395 drm_gem_vm_close(vma); 396 397 return ret; 398 } 399 400 /* low-level interface prime helpers */ 401 struct drm_gem_object *exynos_drm_gem_prime_import(struct drm_device *dev, 402 struct dma_buf *dma_buf) 403 { 404 return drm_gem_prime_import_dev(dev, dma_buf, to_dma_dev(dev)); 405 } 406 407 struct sg_table *exynos_drm_gem_prime_get_sg_table(struct drm_gem_object *obj) 408 { 409 struct exynos_drm_gem *exynos_gem = to_exynos_gem(obj); 410 struct drm_device *drm_dev = obj->dev; 411 struct sg_table *sgt; 412 int ret; 413 414 sgt = kzalloc(sizeof(*sgt), GFP_KERNEL); 415 if (!sgt) 416 return ERR_PTR(-ENOMEM); 417 418 ret = dma_get_sgtable_attrs(to_dma_dev(drm_dev), sgt, exynos_gem->cookie, 419 exynos_gem->dma_addr, exynos_gem->size, 420 exynos_gem->dma_attrs); 421 if (ret) { 422 DRM_ERROR("failed to get sgtable, %d\n", ret); 423 kfree(sgt); 424 return ERR_PTR(ret); 425 } 426 427 return sgt; 428 } 429 430 struct drm_gem_object * 431 exynos_drm_gem_prime_import_sg_table(struct drm_device *dev, 432 struct dma_buf_attachment *attach, 433 struct sg_table *sgt) 434 { 435 struct exynos_drm_gem *exynos_gem; 436 437 /* check if the entries in the sg_table are contiguous */ 438 if (drm_prime_get_contiguous_size(sgt) < attach->dmabuf->size) { 439 DRM_ERROR("buffer chunks must be mapped contiguously"); 440 return ERR_PTR(-EINVAL); 441 } 442 443 exynos_gem = exynos_drm_gem_init(dev, attach->dmabuf->size); 444 if (IS_ERR(exynos_gem)) 445 return ERR_CAST(exynos_gem); 446 447 /* 448 * Buffer has been mapped as contiguous into DMA address space, 449 * but if there is IOMMU, it can be either CONTIG or NONCONTIG. 450 * We assume a simplified logic below: 451 */ 452 if (is_drm_iommu_supported(dev)) 453 exynos_gem->flags |= EXYNOS_BO_NONCONTIG; 454 else 455 exynos_gem->flags |= EXYNOS_BO_CONTIG; 456 457 exynos_gem->dma_addr = sg_dma_address(sgt->sgl); 458 exynos_gem->sgt = sgt; 459 return &exynos_gem->base; 460 } 461