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_device.h> 14 #include <drm/drm_dumb_buffers.h> 15 #include <drm/drm_prime.h> 16 #include <drm/drm_print.h> 17 #include <drm/drm_vma_manager.h> 18 #include <drm/exynos_drm.h> 19 20 #include "exynos_drm_drv.h" 21 #include "exynos_drm_gem.h" 22 23 MODULE_IMPORT_NS("DMA_BUF"); 24 25 static int exynos_drm_gem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma); 26 27 static int exynos_drm_alloc_buf(struct exynos_drm_gem *exynos_gem, bool kvmap) 28 { 29 struct drm_device *dev = exynos_gem->base.dev; 30 unsigned long attr = 0; 31 32 if (exynos_gem->dma_addr) { 33 DRM_DEV_DEBUG_KMS(drm_dev_dma_dev(dev), "already allocated.\n"); 34 return 0; 35 } 36 37 /* 38 * if EXYNOS_BO_CONTIG, fully physically contiguous memory 39 * region will be allocated else physically contiguous 40 * as possible. 41 */ 42 if (!(exynos_gem->flags & EXYNOS_BO_NONCONTIG)) 43 attr |= DMA_ATTR_FORCE_CONTIGUOUS; 44 45 /* 46 * if EXYNOS_BO_WC or EXYNOS_BO_NONCACHABLE, writecombine mapping 47 * else cachable mapping. 48 */ 49 if (exynos_gem->flags & EXYNOS_BO_WC || 50 !(exynos_gem->flags & EXYNOS_BO_CACHABLE)) 51 attr |= DMA_ATTR_WRITE_COMBINE; 52 53 /* FBDev emulation requires kernel mapping */ 54 if (!kvmap) 55 attr |= DMA_ATTR_NO_KERNEL_MAPPING; 56 57 exynos_gem->dma_attrs = attr; 58 exynos_gem->cookie = dma_alloc_attrs(drm_dev_dma_dev(dev), exynos_gem->base.size, 59 &exynos_gem->dma_addr, GFP_KERNEL, 60 exynos_gem->dma_attrs); 61 if (!exynos_gem->cookie) { 62 DRM_DEV_ERROR(drm_dev_dma_dev(dev), "failed to allocate buffer.\n"); 63 return -ENOMEM; 64 } 65 66 if (kvmap) 67 exynos_gem->kvaddr = exynos_gem->cookie; 68 69 DRM_DEV_DEBUG_KMS(drm_dev_dma_dev(dev), "dma_addr(%pad), size(0x%zx)\n", 70 &exynos_gem->dma_addr, exynos_gem->base.size); 71 return 0; 72 } 73 74 static void exynos_drm_free_buf(struct exynos_drm_gem *exynos_gem) 75 { 76 struct drm_device *dev = exynos_gem->base.dev; 77 78 if (!exynos_gem->dma_addr) { 79 DRM_DEV_DEBUG_KMS(dev->dev, "dma_addr is invalid.\n"); 80 return; 81 } 82 83 DRM_DEV_DEBUG_KMS(dev->dev, "dma_addr(0x%pad), size(0x%zx)\n", 84 &exynos_gem->dma_addr, exynos_gem->base.size); 85 86 dma_free_attrs(drm_dev_dma_dev(dev), exynos_gem->base.size, exynos_gem->cookie, 87 (dma_addr_t)exynos_gem->dma_addr, 88 exynos_gem->dma_attrs); 89 } 90 91 static int exynos_drm_gem_handle_create(struct drm_gem_object *obj, 92 struct drm_file *file_priv, 93 unsigned int *handle) 94 { 95 int ret; 96 97 /* 98 * allocate a id of idr table where the obj is registered 99 * and handle has the id what user can see. 100 */ 101 ret = drm_gem_handle_create(file_priv, obj, handle); 102 if (ret) 103 return ret; 104 105 DRM_DEV_DEBUG_KMS(drm_dev_dma_dev(obj->dev), "gem handle = 0x%x\n", *handle); 106 107 /* drop reference from allocate - handle holds it now. */ 108 drm_gem_object_put(obj); 109 110 return 0; 111 } 112 113 void exynos_drm_gem_destroy(struct exynos_drm_gem *exynos_gem) 114 { 115 struct drm_gem_object *obj = &exynos_gem->base; 116 117 DRM_DEV_DEBUG_KMS(drm_dev_dma_dev(obj->dev), "handle count = %d\n", 118 obj->handle_count); 119 120 /* 121 * do not release memory region from exporter. 122 * 123 * the region will be released by exporter 124 * once dmabuf's refcount becomes 0. 125 */ 126 if (obj->import_attach) 127 drm_prime_gem_destroy(obj, exynos_gem->sgt); 128 else 129 exynos_drm_free_buf(exynos_gem); 130 131 /* release file pointer to gem object. */ 132 drm_gem_object_release(obj); 133 134 kfree(exynos_gem); 135 } 136 137 static void exynos_drm_gem_free_object(struct drm_gem_object *obj) 138 { 139 exynos_drm_gem_destroy(to_exynos_gem(obj)); 140 } 141 142 static const struct vm_operations_struct exynos_drm_gem_vm_ops = { 143 .open = drm_gem_vm_open, 144 .close = drm_gem_vm_close, 145 }; 146 147 static const struct drm_gem_object_funcs exynos_drm_gem_object_funcs = { 148 .free = exynos_drm_gem_free_object, 149 .get_sg_table = exynos_drm_gem_prime_get_sg_table, 150 .mmap = exynos_drm_gem_mmap, 151 .vm_ops = &exynos_drm_gem_vm_ops, 152 }; 153 154 static struct exynos_drm_gem *exynos_drm_gem_init(struct drm_device *dev, 155 unsigned long size) 156 { 157 struct exynos_drm_gem *exynos_gem; 158 struct drm_gem_object *obj; 159 int ret; 160 161 exynos_gem = kzalloc_obj(*exynos_gem); 162 if (!exynos_gem) 163 return ERR_PTR(-ENOMEM); 164 165 obj = &exynos_gem->base; 166 167 obj->funcs = &exynos_drm_gem_object_funcs; 168 169 ret = drm_gem_object_init(dev, obj, size); 170 if (ret < 0) { 171 DRM_DEV_ERROR(dev->dev, "failed to initialize gem object\n"); 172 kfree(exynos_gem); 173 return ERR_PTR(ret); 174 } 175 176 ret = drm_gem_create_mmap_offset(obj); 177 if (ret < 0) { 178 drm_gem_object_release(obj); 179 kfree(exynos_gem); 180 return ERR_PTR(ret); 181 } 182 183 DRM_DEV_DEBUG_KMS(dev->dev, "created file object = %p\n", obj->filp); 184 185 return exynos_gem; 186 } 187 188 struct exynos_drm_gem *exynos_drm_gem_create(struct drm_device *dev, 189 unsigned int flags, 190 unsigned long size, 191 bool kvmap) 192 { 193 struct exynos_drm_gem *exynos_gem; 194 int ret; 195 196 if (flags & ~(EXYNOS_BO_MASK)) { 197 DRM_DEV_ERROR(dev->dev, 198 "invalid GEM buffer flags: %u\n", flags); 199 return ERR_PTR(-EINVAL); 200 } 201 202 if (!size) { 203 DRM_DEV_ERROR(dev->dev, "invalid GEM buffer size: %lu\n", size); 204 return ERR_PTR(-EINVAL); 205 } 206 207 size = roundup(size, PAGE_SIZE); 208 209 exynos_gem = exynos_drm_gem_init(dev, size); 210 if (IS_ERR(exynos_gem)) 211 return exynos_gem; 212 213 if (!is_drm_iommu_supported(dev) && (flags & EXYNOS_BO_NONCONTIG)) { 214 /* 215 * when no IOMMU is available, all allocated buffers are 216 * contiguous anyway, so drop EXYNOS_BO_NONCONTIG flag 217 */ 218 flags &= ~EXYNOS_BO_NONCONTIG; 219 DRM_WARN("Non-contiguous allocation is not supported without IOMMU, falling back to contiguous buffer\n"); 220 } 221 222 /* set memory type and cache attribute from user side. */ 223 exynos_gem->flags = flags; 224 225 ret = exynos_drm_alloc_buf(exynos_gem, kvmap); 226 if (ret < 0) { 227 drm_gem_object_release(&exynos_gem->base); 228 kfree(exynos_gem); 229 return ERR_PTR(ret); 230 } 231 232 return exynos_gem; 233 } 234 235 int exynos_drm_gem_create_ioctl(struct drm_device *dev, void *data, 236 struct drm_file *file_priv) 237 { 238 struct drm_exynos_gem_create *args = data; 239 struct exynos_drm_gem *exynos_gem; 240 int ret; 241 242 exynos_gem = exynos_drm_gem_create(dev, args->flags, args->size, false); 243 if (IS_ERR(exynos_gem)) 244 return PTR_ERR(exynos_gem); 245 246 ret = exynos_drm_gem_handle_create(&exynos_gem->base, file_priv, 247 &args->handle); 248 if (ret) { 249 exynos_drm_gem_destroy(exynos_gem); 250 return ret; 251 } 252 253 return 0; 254 } 255 256 int exynos_drm_gem_map_ioctl(struct drm_device *dev, void *data, 257 struct drm_file *file_priv) 258 { 259 struct drm_exynos_gem_map *args = data; 260 261 return drm_gem_dumb_map_offset(file_priv, dev, args->handle, 262 &args->offset); 263 } 264 265 struct exynos_drm_gem *exynos_drm_gem_get(struct drm_file *filp, 266 unsigned int gem_handle) 267 { 268 struct drm_gem_object *obj; 269 270 obj = drm_gem_object_lookup(filp, gem_handle); 271 if (!obj) 272 return NULL; 273 return to_exynos_gem(obj); 274 } 275 276 static int exynos_drm_gem_mmap_buffer(struct exynos_drm_gem *exynos_gem, 277 struct vm_area_struct *vma) 278 { 279 struct drm_device *drm_dev = exynos_gem->base.dev; 280 unsigned long vm_size; 281 int ret; 282 283 vm_flags_clear(vma, VM_PFNMAP); 284 vma->vm_pgoff = 0; 285 286 vm_size = vma->vm_end - vma->vm_start; 287 288 /* check if user-requested size is valid. */ 289 if (vm_size > exynos_gem->base.size) 290 return -EINVAL; 291 292 ret = dma_mmap_attrs(drm_dev_dma_dev(drm_dev), vma, exynos_gem->cookie, 293 exynos_gem->dma_addr, exynos_gem->base.size, 294 exynos_gem->dma_attrs); 295 if (ret < 0) { 296 DRM_ERROR("failed to mmap.\n"); 297 return ret; 298 } 299 300 return 0; 301 } 302 303 int exynos_drm_gem_get_ioctl(struct drm_device *dev, void *data, 304 struct drm_file *file_priv) 305 { 306 struct exynos_drm_gem *exynos_gem; 307 struct drm_exynos_gem_info *args = data; 308 struct drm_gem_object *obj; 309 310 obj = drm_gem_object_lookup(file_priv, args->handle); 311 if (!obj) { 312 DRM_DEV_ERROR(dev->dev, "failed to lookup gem object.\n"); 313 return -EINVAL; 314 } 315 316 exynos_gem = to_exynos_gem(obj); 317 318 args->flags = exynos_gem->flags; 319 args->size = obj->size; 320 321 drm_gem_object_put(obj); 322 323 return 0; 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(drm_dev_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 sg_table *exynos_drm_gem_prime_get_sg_table(struct drm_gem_object *obj) 402 { 403 struct exynos_drm_gem *exynos_gem = to_exynos_gem(obj); 404 struct drm_device *drm_dev = obj->dev; 405 struct sg_table *sgt; 406 int ret; 407 408 sgt = kzalloc_obj(*sgt); 409 if (!sgt) 410 return ERR_PTR(-ENOMEM); 411 412 ret = dma_get_sgtable_attrs(drm_dev_dma_dev(drm_dev), sgt, exynos_gem->cookie, 413 exynos_gem->dma_addr, obj->size, 414 exynos_gem->dma_attrs); 415 if (ret) { 416 DRM_ERROR("failed to get sgtable, %d\n", ret); 417 kfree(sgt); 418 return ERR_PTR(ret); 419 } 420 421 return sgt; 422 } 423 424 struct drm_gem_object * 425 exynos_drm_gem_prime_import_sg_table(struct drm_device *dev, 426 struct dma_buf_attachment *attach, 427 struct sg_table *sgt) 428 { 429 struct exynos_drm_gem *exynos_gem; 430 431 /* check if the entries in the sg_table are contiguous */ 432 if (drm_prime_get_contiguous_size(sgt) < attach->dmabuf->size) { 433 DRM_ERROR("buffer chunks must be mapped contiguously"); 434 return ERR_PTR(-EINVAL); 435 } 436 437 exynos_gem = exynos_drm_gem_init(dev, attach->dmabuf->size); 438 if (IS_ERR(exynos_gem)) 439 return ERR_CAST(exynos_gem); 440 441 /* 442 * Buffer has been mapped as contiguous into DMA address space, 443 * but if there is IOMMU, it can be either CONTIG or NONCONTIG. 444 * We assume a simplified logic below: 445 */ 446 if (is_drm_iommu_supported(dev)) 447 exynos_gem->flags |= EXYNOS_BO_NONCONTIG; 448 else 449 exynos_gem->flags |= EXYNOS_BO_CONTIG; 450 451 exynos_gem->dma_addr = sg_dma_address(sgt->sgl); 452 exynos_gem->sgt = sgt; 453 return &exynos_gem->base; 454 } 455