drm_gem_cma_helper.c 19 KB

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  1. // SPDX-License-Identifier: GPL-2.0-or-later
  2. /*
  3. * drm gem CMA (contiguous memory allocator) helper functions
  4. *
  5. * Copyright (C) 2012 Sascha Hauer, Pengutronix
  6. *
  7. * Based on Samsung Exynos code
  8. *
  9. * Copyright (c) 2011 Samsung Electronics Co., Ltd.
  10. */
  11. #include <linux/dma-buf.h>
  12. #include <linux/dma-mapping.h>
  13. #include <linux/export.h>
  14. #include <linux/mm.h>
  15. #include <linux/mutex.h>
  16. #include <linux/slab.h>
  17. #include <drm/drm.h>
  18. #include <drm/drm_device.h>
  19. #include <drm/drm_drv.h>
  20. #include <drm/drm_gem_cma_helper.h>
  21. #include <drm/drm_vma_manager.h>
  22. /**
  23. * DOC: cma helpers
  24. *
  25. * The Contiguous Memory Allocator reserves a pool of memory at early boot
  26. * that is used to service requests for large blocks of contiguous memory.
  27. *
  28. * The DRM GEM/CMA helpers use this allocator as a means to provide buffer
  29. * objects that are physically contiguous in memory. This is useful for
  30. * display drivers that are unable to map scattered buffers via an IOMMU.
  31. */
  32. /**
  33. * __drm_gem_cma_create - Create a GEM CMA object without allocating memory
  34. * @drm: DRM device
  35. * @size: size of the object to allocate
  36. *
  37. * This function creates and initializes a GEM CMA object of the given size,
  38. * but doesn't allocate any memory to back the object.
  39. *
  40. * Returns:
  41. * A struct drm_gem_cma_object * on success or an ERR_PTR()-encoded negative
  42. * error code on failure.
  43. */
  44. static struct drm_gem_cma_object *
  45. __drm_gem_cma_create(struct drm_device *drm, size_t size)
  46. {
  47. struct drm_gem_cma_object *cma_obj;
  48. struct drm_gem_object *gem_obj;
  49. int ret;
  50. if (drm->driver->gem_create_object)
  51. gem_obj = drm->driver->gem_create_object(drm, size);
  52. else
  53. gem_obj = kzalloc(sizeof(*cma_obj), GFP_KERNEL);
  54. if (!gem_obj)
  55. return ERR_PTR(-ENOMEM);
  56. cma_obj = container_of(gem_obj, struct drm_gem_cma_object, base);
  57. ret = drm_gem_object_init(drm, gem_obj, size);
  58. if (ret)
  59. goto error;
  60. ret = drm_gem_create_mmap_offset(gem_obj);
  61. if (ret) {
  62. drm_gem_object_release(gem_obj);
  63. goto error;
  64. }
  65. return cma_obj;
  66. error:
  67. kfree(cma_obj);
  68. return ERR_PTR(ret);
  69. }
  70. /**
  71. * drm_gem_cma_create - allocate an object with the given size
  72. * @drm: DRM device
  73. * @size: size of the object to allocate
  74. *
  75. * This function creates a CMA GEM object and allocates a contiguous chunk of
  76. * memory as backing store. The backing memory has the writecombine attribute
  77. * set.
  78. *
  79. * Returns:
  80. * A struct drm_gem_cma_object * on success or an ERR_PTR()-encoded negative
  81. * error code on failure.
  82. */
  83. struct drm_gem_cma_object *drm_gem_cma_create(struct drm_device *drm,
  84. size_t size)
  85. {
  86. struct drm_gem_cma_object *cma_obj;
  87. int ret;
  88. size = round_up(size, PAGE_SIZE);
  89. cma_obj = __drm_gem_cma_create(drm, size);
  90. if (IS_ERR(cma_obj))
  91. return cma_obj;
  92. cma_obj->vaddr = dma_alloc_wc(drm->dev, size, &cma_obj->paddr,
  93. GFP_KERNEL | __GFP_NOWARN);
  94. if (!cma_obj->vaddr) {
  95. drm_dbg(drm, "failed to allocate buffer with size %zu\n",
  96. size);
  97. ret = -ENOMEM;
  98. goto error;
  99. }
  100. return cma_obj;
  101. error:
  102. drm_gem_object_put(&cma_obj->base);
  103. return ERR_PTR(ret);
  104. }
  105. EXPORT_SYMBOL_GPL(drm_gem_cma_create);
  106. /**
  107. * drm_gem_cma_create_with_handle - allocate an object with the given size and
  108. * return a GEM handle to it
  109. * @file_priv: DRM file-private structure to register the handle for
  110. * @drm: DRM device
  111. * @size: size of the object to allocate
  112. * @handle: return location for the GEM handle
  113. *
  114. * This function creates a CMA GEM object, allocating a physically contiguous
  115. * chunk of memory as backing store. The GEM object is then added to the list
  116. * of object associated with the given file and a handle to it is returned.
  117. *
  118. * Returns:
  119. * A struct drm_gem_cma_object * on success or an ERR_PTR()-encoded negative
  120. * error code on failure.
  121. */
  122. static struct drm_gem_cma_object *
  123. drm_gem_cma_create_with_handle(struct drm_file *file_priv,
  124. struct drm_device *drm, size_t size,
  125. uint32_t *handle)
  126. {
  127. struct drm_gem_cma_object *cma_obj;
  128. struct drm_gem_object *gem_obj;
  129. int ret;
  130. cma_obj = drm_gem_cma_create(drm, size);
  131. if (IS_ERR(cma_obj))
  132. return cma_obj;
  133. gem_obj = &cma_obj->base;
  134. /*
  135. * allocate a id of idr table where the obj is registered
  136. * and handle has the id what user can see.
  137. */
  138. ret = drm_gem_handle_create(file_priv, gem_obj, handle);
  139. /* drop reference from allocate - handle holds it now. */
  140. drm_gem_object_put(gem_obj);
  141. if (ret)
  142. return ERR_PTR(ret);
  143. return cma_obj;
  144. }
  145. /**
  146. * drm_gem_cma_free_object - free resources associated with a CMA GEM object
  147. * @gem_obj: GEM object to free
  148. *
  149. * This function frees the backing memory of the CMA GEM object, cleans up the
  150. * GEM object state and frees the memory used to store the object itself.
  151. * If the buffer is imported and the virtual address is set, it is released.
  152. * Drivers using the CMA helpers should set this as their
  153. * &drm_driver.gem_free_object_unlocked callback.
  154. */
  155. void drm_gem_cma_free_object(struct drm_gem_object *gem_obj)
  156. {
  157. struct drm_gem_cma_object *cma_obj;
  158. cma_obj = to_drm_gem_cma_obj(gem_obj);
  159. if (gem_obj->import_attach) {
  160. if (cma_obj->vaddr)
  161. dma_buf_vunmap(gem_obj->import_attach->dmabuf, cma_obj->vaddr);
  162. drm_prime_gem_destroy(gem_obj, cma_obj->sgt);
  163. } else if (cma_obj->vaddr) {
  164. dma_free_wc(gem_obj->dev->dev, cma_obj->base.size,
  165. cma_obj->vaddr, cma_obj->paddr);
  166. }
  167. drm_gem_object_release(gem_obj);
  168. kfree(cma_obj);
  169. }
  170. EXPORT_SYMBOL_GPL(drm_gem_cma_free_object);
  171. /**
  172. * drm_gem_cma_dumb_create_internal - create a dumb buffer object
  173. * @file_priv: DRM file-private structure to create the dumb buffer for
  174. * @drm: DRM device
  175. * @args: IOCTL data
  176. *
  177. * This aligns the pitch and size arguments to the minimum required. This is
  178. * an internal helper that can be wrapped by a driver to account for hardware
  179. * with more specific alignment requirements. It should not be used directly
  180. * as their &drm_driver.dumb_create callback.
  181. *
  182. * Returns:
  183. * 0 on success or a negative error code on failure.
  184. */
  185. int drm_gem_cma_dumb_create_internal(struct drm_file *file_priv,
  186. struct drm_device *drm,
  187. struct drm_mode_create_dumb *args)
  188. {
  189. unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
  190. struct drm_gem_cma_object *cma_obj;
  191. if (args->pitch < min_pitch)
  192. args->pitch = min_pitch;
  193. if (args->size < args->pitch * args->height)
  194. args->size = args->pitch * args->height;
  195. cma_obj = drm_gem_cma_create_with_handle(file_priv, drm, args->size,
  196. &args->handle);
  197. return PTR_ERR_OR_ZERO(cma_obj);
  198. }
  199. EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_create_internal);
  200. /**
  201. * drm_gem_cma_dumb_create - create a dumb buffer object
  202. * @file_priv: DRM file-private structure to create the dumb buffer for
  203. * @drm: DRM device
  204. * @args: IOCTL data
  205. *
  206. * This function computes the pitch of the dumb buffer and rounds it up to an
  207. * integer number of bytes per pixel. Drivers for hardware that doesn't have
  208. * any additional restrictions on the pitch can directly use this function as
  209. * their &drm_driver.dumb_create callback.
  210. *
  211. * For hardware with additional restrictions, drivers can adjust the fields
  212. * set up by userspace and pass the IOCTL data along to the
  213. * drm_gem_cma_dumb_create_internal() function.
  214. *
  215. * Returns:
  216. * 0 on success or a negative error code on failure.
  217. */
  218. int drm_gem_cma_dumb_create(struct drm_file *file_priv,
  219. struct drm_device *drm,
  220. struct drm_mode_create_dumb *args)
  221. {
  222. struct drm_gem_cma_object *cma_obj;
  223. args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
  224. args->size = args->pitch * args->height;
  225. cma_obj = drm_gem_cma_create_with_handle(file_priv, drm, args->size,
  226. &args->handle);
  227. return PTR_ERR_OR_ZERO(cma_obj);
  228. }
  229. EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_create);
  230. const struct vm_operations_struct drm_gem_cma_vm_ops = {
  231. .open = drm_gem_vm_open,
  232. .close = drm_gem_vm_close,
  233. };
  234. EXPORT_SYMBOL_GPL(drm_gem_cma_vm_ops);
  235. static int drm_gem_cma_mmap_obj(struct drm_gem_cma_object *cma_obj,
  236. struct vm_area_struct *vma)
  237. {
  238. int ret;
  239. /*
  240. * Clear the VM_PFNMAP flag that was set by drm_gem_mmap(), and set the
  241. * vm_pgoff (used as a fake buffer offset by DRM) to 0 as we want to map
  242. * the whole buffer.
  243. */
  244. vma->vm_flags &= ~VM_PFNMAP;
  245. vma->vm_pgoff = 0;
  246. ret = dma_mmap_wc(cma_obj->base.dev->dev, vma, cma_obj->vaddr,
  247. cma_obj->paddr, vma->vm_end - vma->vm_start);
  248. if (ret)
  249. drm_gem_vm_close(vma);
  250. return ret;
  251. }
  252. /**
  253. * drm_gem_cma_mmap - memory-map a CMA GEM object
  254. * @filp: file object
  255. * @vma: VMA for the area to be mapped
  256. *
  257. * This function implements an augmented version of the GEM DRM file mmap
  258. * operation for CMA objects: In addition to the usual GEM VMA setup it
  259. * immediately faults in the entire object instead of using on-demaind
  260. * faulting. Drivers which employ the CMA helpers should use this function
  261. * as their ->mmap() handler in the DRM device file's file_operations
  262. * structure.
  263. *
  264. * Instead of directly referencing this function, drivers should use the
  265. * DEFINE_DRM_GEM_CMA_FOPS().macro.
  266. *
  267. * Returns:
  268. * 0 on success or a negative error code on failure.
  269. */
  270. int drm_gem_cma_mmap(struct file *filp, struct vm_area_struct *vma)
  271. {
  272. struct drm_gem_cma_object *cma_obj;
  273. struct drm_gem_object *gem_obj;
  274. int ret;
  275. ret = drm_gem_mmap(filp, vma);
  276. if (ret)
  277. return ret;
  278. gem_obj = vma->vm_private_data;
  279. cma_obj = to_drm_gem_cma_obj(gem_obj);
  280. return drm_gem_cma_mmap_obj(cma_obj, vma);
  281. }
  282. EXPORT_SYMBOL_GPL(drm_gem_cma_mmap);
  283. #ifndef CONFIG_MMU
  284. /**
  285. * drm_gem_cma_get_unmapped_area - propose address for mapping in noMMU cases
  286. * @filp: file object
  287. * @addr: memory address
  288. * @len: buffer size
  289. * @pgoff: page offset
  290. * @flags: memory flags
  291. *
  292. * This function is used in noMMU platforms to propose address mapping
  293. * for a given buffer.
  294. * It's intended to be used as a direct handler for the struct
  295. * &file_operations.get_unmapped_area operation.
  296. *
  297. * Returns:
  298. * mapping address on success or a negative error code on failure.
  299. */
  300. unsigned long drm_gem_cma_get_unmapped_area(struct file *filp,
  301. unsigned long addr,
  302. unsigned long len,
  303. unsigned long pgoff,
  304. unsigned long flags)
  305. {
  306. struct drm_gem_cma_object *cma_obj;
  307. struct drm_gem_object *obj = NULL;
  308. struct drm_file *priv = filp->private_data;
  309. struct drm_device *dev = priv->minor->dev;
  310. struct drm_vma_offset_node *node;
  311. if (drm_dev_is_unplugged(dev))
  312. return -ENODEV;
  313. drm_vma_offset_lock_lookup(dev->vma_offset_manager);
  314. node = drm_vma_offset_exact_lookup_locked(dev->vma_offset_manager,
  315. pgoff,
  316. len >> PAGE_SHIFT);
  317. if (likely(node)) {
  318. obj = container_of(node, struct drm_gem_object, vma_node);
  319. /*
  320. * When the object is being freed, after it hits 0-refcnt it
  321. * proceeds to tear down the object. In the process it will
  322. * attempt to remove the VMA offset and so acquire this
  323. * mgr->vm_lock. Therefore if we find an object with a 0-refcnt
  324. * that matches our range, we know it is in the process of being
  325. * destroyed and will be freed as soon as we release the lock -
  326. * so we have to check for the 0-refcnted object and treat it as
  327. * invalid.
  328. */
  329. if (!kref_get_unless_zero(&obj->refcount))
  330. obj = NULL;
  331. }
  332. drm_vma_offset_unlock_lookup(dev->vma_offset_manager);
  333. if (!obj)
  334. return -EINVAL;
  335. if (!drm_vma_node_is_allowed(node, priv)) {
  336. drm_gem_object_put(obj);
  337. return -EACCES;
  338. }
  339. cma_obj = to_drm_gem_cma_obj(obj);
  340. drm_gem_object_put(obj);
  341. return cma_obj->vaddr ? (unsigned long)cma_obj->vaddr : -EINVAL;
  342. }
  343. EXPORT_SYMBOL_GPL(drm_gem_cma_get_unmapped_area);
  344. #endif
  345. /**
  346. * drm_gem_cma_print_info() - Print &drm_gem_cma_object info for debugfs
  347. * @p: DRM printer
  348. * @indent: Tab indentation level
  349. * @obj: GEM object
  350. *
  351. * This function can be used as the &drm_driver->gem_print_info callback.
  352. * It prints paddr and vaddr for use in e.g. debugfs output.
  353. */
  354. void drm_gem_cma_print_info(struct drm_printer *p, unsigned int indent,
  355. const struct drm_gem_object *obj)
  356. {
  357. const struct drm_gem_cma_object *cma_obj = to_drm_gem_cma_obj(obj);
  358. drm_printf_indent(p, indent, "paddr=%pad\n", &cma_obj->paddr);
  359. drm_printf_indent(p, indent, "vaddr=%p\n", cma_obj->vaddr);
  360. }
  361. EXPORT_SYMBOL(drm_gem_cma_print_info);
  362. /**
  363. * drm_gem_cma_prime_get_sg_table - provide a scatter/gather table of pinned
  364. * pages for a CMA GEM object
  365. * @obj: GEM object
  366. *
  367. * This function exports a scatter/gather table suitable for PRIME usage by
  368. * calling the standard DMA mapping API. Drivers using the CMA helpers should
  369. * set this as their &drm_driver.gem_prime_get_sg_table callback.
  370. *
  371. * Returns:
  372. * A pointer to the scatter/gather table of pinned pages or NULL on failure.
  373. */
  374. struct sg_table *drm_gem_cma_prime_get_sg_table(struct drm_gem_object *obj)
  375. {
  376. struct drm_gem_cma_object *cma_obj = to_drm_gem_cma_obj(obj);
  377. struct sg_table *sgt;
  378. int ret;
  379. sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
  380. if (!sgt)
  381. return ERR_PTR(-ENOMEM);
  382. ret = dma_get_sgtable(obj->dev->dev, sgt, cma_obj->vaddr,
  383. cma_obj->paddr, obj->size);
  384. if (ret < 0)
  385. goto out;
  386. return sgt;
  387. out:
  388. kfree(sgt);
  389. return ERR_PTR(ret);
  390. }
  391. EXPORT_SYMBOL_GPL(drm_gem_cma_prime_get_sg_table);
  392. /**
  393. * drm_gem_cma_prime_import_sg_table - produce a CMA GEM object from another
  394. * driver's scatter/gather table of pinned pages
  395. * @dev: device to import into
  396. * @attach: DMA-BUF attachment
  397. * @sgt: scatter/gather table of pinned pages
  398. *
  399. * This function imports a scatter/gather table exported via DMA-BUF by
  400. * another driver. Imported buffers must be physically contiguous in memory
  401. * (i.e. the scatter/gather table must contain a single entry). Drivers that
  402. * use the CMA helpers should set this as their
  403. * &drm_driver.gem_prime_import_sg_table callback.
  404. *
  405. * Returns:
  406. * A pointer to a newly created GEM object or an ERR_PTR-encoded negative
  407. * error code on failure.
  408. */
  409. struct drm_gem_object *
  410. drm_gem_cma_prime_import_sg_table(struct drm_device *dev,
  411. struct dma_buf_attachment *attach,
  412. struct sg_table *sgt)
  413. {
  414. struct drm_gem_cma_object *cma_obj;
  415. /* check if the entries in the sg_table are contiguous */
  416. if (drm_prime_get_contiguous_size(sgt) < attach->dmabuf->size)
  417. return ERR_PTR(-EINVAL);
  418. /* Create a CMA GEM buffer. */
  419. cma_obj = __drm_gem_cma_create(dev, attach->dmabuf->size);
  420. if (IS_ERR(cma_obj))
  421. return ERR_CAST(cma_obj);
  422. cma_obj->paddr = sg_dma_address(sgt->sgl);
  423. cma_obj->sgt = sgt;
  424. DRM_DEBUG_PRIME("dma_addr = %pad, size = %zu\n", &cma_obj->paddr, attach->dmabuf->size);
  425. return &cma_obj->base;
  426. }
  427. EXPORT_SYMBOL_GPL(drm_gem_cma_prime_import_sg_table);
  428. /**
  429. * drm_gem_cma_prime_mmap - memory-map an exported CMA GEM object
  430. * @obj: GEM object
  431. * @vma: VMA for the area to be mapped
  432. *
  433. * This function maps a buffer imported via DRM PRIME into a userspace
  434. * process's address space. Drivers that use the CMA helpers should set this
  435. * as their &drm_driver.gem_prime_mmap callback.
  436. *
  437. * Returns:
  438. * 0 on success or a negative error code on failure.
  439. */
  440. int drm_gem_cma_prime_mmap(struct drm_gem_object *obj,
  441. struct vm_area_struct *vma)
  442. {
  443. struct drm_gem_cma_object *cma_obj;
  444. int ret;
  445. ret = drm_gem_mmap_obj(obj, obj->size, vma);
  446. if (ret < 0)
  447. return ret;
  448. cma_obj = to_drm_gem_cma_obj(obj);
  449. return drm_gem_cma_mmap_obj(cma_obj, vma);
  450. }
  451. EXPORT_SYMBOL_GPL(drm_gem_cma_prime_mmap);
  452. /**
  453. * drm_gem_cma_prime_vmap - map a CMA GEM object into the kernel's virtual
  454. * address space
  455. * @obj: GEM object
  456. *
  457. * This function maps a buffer exported via DRM PRIME into the kernel's
  458. * virtual address space. Since the CMA buffers are already mapped into the
  459. * kernel virtual address space this simply returns the cached virtual
  460. * address. Drivers using the CMA helpers should set this as their DRM
  461. * driver's &drm_driver.gem_prime_vmap callback.
  462. *
  463. * Returns:
  464. * The kernel virtual address of the CMA GEM object's backing store.
  465. */
  466. void *drm_gem_cma_prime_vmap(struct drm_gem_object *obj)
  467. {
  468. struct drm_gem_cma_object *cma_obj = to_drm_gem_cma_obj(obj);
  469. return cma_obj->vaddr;
  470. }
  471. EXPORT_SYMBOL_GPL(drm_gem_cma_prime_vmap);
  472. /**
  473. * drm_gem_cma_prime_vunmap - unmap a CMA GEM object from the kernel's virtual
  474. * address space
  475. * @obj: GEM object
  476. * @vaddr: kernel virtual address where the CMA GEM object was mapped
  477. *
  478. * This function removes a buffer exported via DRM PRIME from the kernel's
  479. * virtual address space. This is a no-op because CMA buffers cannot be
  480. * unmapped from kernel space. Drivers using the CMA helpers should set this
  481. * as their &drm_driver.gem_prime_vunmap callback.
  482. */
  483. void drm_gem_cma_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
  484. {
  485. /* Nothing to do */
  486. }
  487. EXPORT_SYMBOL_GPL(drm_gem_cma_prime_vunmap);
  488. static const struct drm_gem_object_funcs drm_gem_cma_default_funcs = {
  489. .free = drm_gem_cma_free_object,
  490. .print_info = drm_gem_cma_print_info,
  491. .get_sg_table = drm_gem_cma_prime_get_sg_table,
  492. .vmap = drm_gem_cma_prime_vmap,
  493. .vm_ops = &drm_gem_cma_vm_ops,
  494. };
  495. /**
  496. * drm_gem_cma_create_object_default_funcs - Create a CMA GEM object with a
  497. * default function table
  498. * @dev: DRM device
  499. * @size: Size of the object to allocate
  500. *
  501. * This sets the GEM object functions to the default CMA helper functions.
  502. * This function can be used as the &drm_driver.gem_create_object callback.
  503. *
  504. * Returns:
  505. * A pointer to a allocated GEM object or an error pointer on failure.
  506. */
  507. struct drm_gem_object *
  508. drm_gem_cma_create_object_default_funcs(struct drm_device *dev, size_t size)
  509. {
  510. struct drm_gem_cma_object *cma_obj;
  511. cma_obj = kzalloc(sizeof(*cma_obj), GFP_KERNEL);
  512. if (!cma_obj)
  513. return NULL;
  514. cma_obj->base.funcs = &drm_gem_cma_default_funcs;
  515. return &cma_obj->base;
  516. }
  517. EXPORT_SYMBOL(drm_gem_cma_create_object_default_funcs);
  518. /**
  519. * drm_gem_cma_prime_import_sg_table_vmap - PRIME import another driver's
  520. * scatter/gather table and get the virtual address of the buffer
  521. * @dev: DRM device
  522. * @attach: DMA-BUF attachment
  523. * @sgt: Scatter/gather table of pinned pages
  524. *
  525. * This function imports a scatter/gather table using
  526. * drm_gem_cma_prime_import_sg_table() and uses dma_buf_vmap() to get the kernel
  527. * virtual address. This ensures that a CMA GEM object always has its virtual
  528. * address set. This address is released when the object is freed.
  529. *
  530. * This function can be used as the &drm_driver.gem_prime_import_sg_table
  531. * callback. The &DRM_GEM_CMA_DRIVER_OPS_VMAP macro provides a shortcut to set
  532. * the necessary DRM driver operations.
  533. *
  534. * Returns:
  535. * A pointer to a newly created GEM object or an ERR_PTR-encoded negative
  536. * error code on failure.
  537. */
  538. struct drm_gem_object *
  539. drm_gem_cma_prime_import_sg_table_vmap(struct drm_device *dev,
  540. struct dma_buf_attachment *attach,
  541. struct sg_table *sgt)
  542. {
  543. struct drm_gem_cma_object *cma_obj;
  544. struct drm_gem_object *obj;
  545. void *vaddr;
  546. vaddr = dma_buf_vmap(attach->dmabuf);
  547. if (!vaddr) {
  548. DRM_ERROR("Failed to vmap PRIME buffer\n");
  549. return ERR_PTR(-ENOMEM);
  550. }
  551. obj = drm_gem_cma_prime_import_sg_table(dev, attach, sgt);
  552. if (IS_ERR(obj)) {
  553. dma_buf_vunmap(attach->dmabuf, vaddr);
  554. return obj;
  555. }
  556. cma_obj = to_drm_gem_cma_obj(obj);
  557. cma_obj->vaddr = vaddr;
  558. return obj;
  559. }
  560. EXPORT_SYMBOL(drm_gem_cma_prime_import_sg_table_vmap);