| 1 | /* |
| 2 | * Copyright © 2008 Intel Corporation |
| 3 | * |
| 4 | * Permission is hereby granted, free of charge, to any person obtaining a |
| 5 | * copy of this software and associated documentation files (the "Software"), |
| 6 | * to deal in the Software without restriction, including without limitation |
| 7 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| 8 | * and/or sell copies of the Software, and to permit persons to whom the |
| 9 | * Software is furnished to do so, subject to the following conditions: |
| 10 | * |
| 11 | * The above copyright notice and this permission notice (including the next |
| 12 | * paragraph) shall be included in all copies or substantial portions of the |
| 13 | * Software. |
| 14 | * |
| 15 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 16 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 17 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| 18 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 19 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| 20 | * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
| 21 | * IN THE SOFTWARE. |
| 22 | * |
| 23 | * Authors: |
| 24 | * Eric Anholt <eric@anholt.net> |
| 25 | * |
| 26 | */ |
| 27 | |
| 28 | #include <linux/types.h> |
| 29 | #include <linux/slab.h> |
| 30 | #include <linux/mm.h> |
| 31 | #include <linux/uaccess.h> |
| 32 | #include <linux/fs.h> |
| 33 | #include <linux/file.h> |
| 34 | #include <linux/module.h> |
| 35 | #include <linux/mman.h> |
| 36 | #include <linux/pagemap.h> |
| 37 | #include <linux/shmem_fs.h> |
| 38 | #include <linux/dma-buf.h> |
| 39 | #include <linux/err.h> |
| 40 | #include <linux/export.h> |
| 41 | #include <asm/bug.h> |
| 42 | #include <drm/drmP.h> |
| 43 | #include <drm/drm_vma_manager.h> |
| 44 | |
| 45 | #ifdef __NetBSD__ |
| 46 | #include <uvm/uvm_extern.h> |
| 47 | #endif |
| 48 | |
| 49 | /** @file drm_gem.c |
| 50 | * |
| 51 | * This file provides some of the base ioctls and library routines for |
| 52 | * the graphics memory manager implemented by each device driver. |
| 53 | * |
| 54 | * Because various devices have different requirements in terms of |
| 55 | * synchronization and migration strategies, implementing that is left up to |
| 56 | * the driver, and all that the general API provides should be generic -- |
| 57 | * allocating objects, reading/writing data with the cpu, freeing objects. |
| 58 | * Even there, platform-dependent optimizations for reading/writing data with |
| 59 | * the CPU mean we'll likely hook those out to driver-specific calls. However, |
| 60 | * the DRI2 implementation wants to have at least allocate/mmap be generic. |
| 61 | * |
| 62 | * The goal was to have swap-backed object allocation managed through |
| 63 | * struct file. However, file descriptors as handles to a struct file have |
| 64 | * two major failings: |
| 65 | * - Process limits prevent more than 1024 or so being used at a time by |
| 66 | * default. |
| 67 | * - Inability to allocate high fds will aggravate the X Server's select() |
| 68 | * handling, and likely that of many GL client applications as well. |
| 69 | * |
| 70 | * This led to a plan of using our own integer IDs (called handles, following |
| 71 | * DRM terminology) to mimic fds, and implement the fd syscalls we need as |
| 72 | * ioctls. The objects themselves will still include the struct file so |
| 73 | * that we can transition to fds if the required kernel infrastructure shows |
| 74 | * up at a later date, and as our interface with shmfs for memory allocation. |
| 75 | */ |
| 76 | |
| 77 | /* |
| 78 | * We make up offsets for buffer objects so we can recognize them at |
| 79 | * mmap time. |
| 80 | */ |
| 81 | |
| 82 | /* pgoff in mmap is an unsigned long, so we need to make sure that |
| 83 | * the faked up offset will fit |
| 84 | */ |
| 85 | |
| 86 | #if BITS_PER_LONG == 64 |
| 87 | #define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFFUL >> PAGE_SHIFT) + 1) |
| 88 | #define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFFUL >> PAGE_SHIFT) * 16) |
| 89 | #else |
| 90 | #define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFUL >> PAGE_SHIFT) + 1) |
| 91 | #define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFUL >> PAGE_SHIFT) * 16) |
| 92 | #endif |
| 93 | |
| 94 | /** |
| 95 | * drm_gem_init - Initialize the GEM device fields |
| 96 | * @dev: drm_devic structure to initialize |
| 97 | */ |
| 98 | int |
| 99 | drm_gem_init(struct drm_device *dev) |
| 100 | { |
| 101 | struct drm_vma_offset_manager *vma_offset_manager; |
| 102 | |
| 103 | #ifdef __NetBSD__ |
| 104 | linux_mutex_init(&dev->object_name_lock); |
| 105 | #else |
| 106 | mutex_init(&dev->object_name_lock); |
| 107 | #endif |
| 108 | idr_init(&dev->object_name_idr); |
| 109 | |
| 110 | vma_offset_manager = kzalloc(sizeof(*vma_offset_manager), GFP_KERNEL); |
| 111 | if (!vma_offset_manager) { |
| 112 | DRM_ERROR("out of memory\n" ); |
| 113 | return -ENOMEM; |
| 114 | } |
| 115 | |
| 116 | dev->vma_offset_manager = vma_offset_manager; |
| 117 | drm_vma_offset_manager_init(vma_offset_manager, |
| 118 | DRM_FILE_PAGE_OFFSET_START, |
| 119 | DRM_FILE_PAGE_OFFSET_SIZE); |
| 120 | |
| 121 | return 0; |
| 122 | } |
| 123 | |
| 124 | void |
| 125 | drm_gem_destroy(struct drm_device *dev) |
| 126 | { |
| 127 | |
| 128 | drm_vma_offset_manager_destroy(dev->vma_offset_manager); |
| 129 | kfree(dev->vma_offset_manager); |
| 130 | dev->vma_offset_manager = NULL; |
| 131 | |
| 132 | idr_destroy(&dev->object_name_idr); |
| 133 | #ifdef __NetBSD__ |
| 134 | linux_mutex_destroy(&dev->object_name_lock); |
| 135 | #endif |
| 136 | } |
| 137 | |
| 138 | /** |
| 139 | * drm_gem_object_init - initialize an allocated shmem-backed GEM object |
| 140 | * @dev: drm_device the object should be initialized for |
| 141 | * @obj: drm_gem_object to initialize |
| 142 | * @size: object size |
| 143 | * |
| 144 | * Initialize an already allocated GEM object of the specified size with |
| 145 | * shmfs backing store. |
| 146 | */ |
| 147 | int drm_gem_object_init(struct drm_device *dev, |
| 148 | struct drm_gem_object *obj, size_t size) |
| 149 | { |
| 150 | #ifndef __NetBSD__ |
| 151 | struct file *filp; |
| 152 | #endif |
| 153 | |
| 154 | drm_gem_private_object_init(dev, obj, size); |
| 155 | |
| 156 | #ifdef __NetBSD__ |
| 157 | /* |
| 158 | * A uao may not have size 0, but a gem object may. Allocate a |
| 159 | * spurious page so we needn't teach uao how to have size 0. |
| 160 | */ |
| 161 | obj->gemo_shm_uao = uao_create(MAX(size, PAGE_SIZE), 0); |
| 162 | /* |
| 163 | * XXX This is gross. We ought to do it the other way around: |
| 164 | * set the uao to have the main uvm object's lock. However, |
| 165 | * uvm_obj_setlock is not safe on uvm_aobjs. |
| 166 | */ |
| 167 | mutex_obj_hold(obj->gemo_shm_uao->vmobjlock); |
| 168 | uvm_obj_setlock(&obj->gemo_uvmobj, obj->gemo_shm_uao->vmobjlock); |
| 169 | #else |
| 170 | filp = shmem_file_setup("drm mm object" , size, VM_NORESERVE); |
| 171 | if (IS_ERR(filp)) |
| 172 | return PTR_ERR(filp); |
| 173 | |
| 174 | obj->filp = filp; |
| 175 | #endif |
| 176 | |
| 177 | return 0; |
| 178 | } |
| 179 | EXPORT_SYMBOL(drm_gem_object_init); |
| 180 | |
| 181 | /** |
| 182 | * drm_gem_object_init - initialize an allocated private GEM object |
| 183 | * @dev: drm_device the object should be initialized for |
| 184 | * @obj: drm_gem_object to initialize |
| 185 | * @size: object size |
| 186 | * |
| 187 | * Initialize an already allocated GEM object of the specified size with |
| 188 | * no GEM provided backing store. Instead the caller is responsible for |
| 189 | * backing the object and handling it. |
| 190 | */ |
| 191 | void drm_gem_private_object_init(struct drm_device *dev, |
| 192 | struct drm_gem_object *obj, size_t size) |
| 193 | { |
| 194 | BUG_ON((size & (PAGE_SIZE - 1)) != 0); |
| 195 | |
| 196 | obj->dev = dev; |
| 197 | #ifdef __NetBSD__ |
| 198 | obj->gemo_shm_uao = NULL; |
| 199 | KASSERT(drm_core_check_feature(dev, DRIVER_GEM)); |
| 200 | KASSERT(dev->driver->gem_uvm_ops != NULL); |
| 201 | uvm_obj_init(&obj->gemo_uvmobj, dev->driver->gem_uvm_ops, true, 1); |
| 202 | #else |
| 203 | obj->filp = NULL; |
| 204 | #endif |
| 205 | |
| 206 | kref_init(&obj->refcount); |
| 207 | obj->handle_count = 0; |
| 208 | obj->size = size; |
| 209 | #ifdef __NetBSD__ |
| 210 | drm_vma_node_init(&obj->vma_node); |
| 211 | #else |
| 212 | drm_vma_node_reset(&obj->vma_node); |
| 213 | #endif |
| 214 | } |
| 215 | EXPORT_SYMBOL(drm_gem_private_object_init); |
| 216 | |
| 217 | static void |
| 218 | drm_gem_remove_prime_handles(struct drm_gem_object *obj, struct drm_file *filp) |
| 219 | { |
| 220 | #ifndef __NetBSD__ /* XXX drm prime */ |
| 221 | /* |
| 222 | * Note: obj->dma_buf can't disappear as long as we still hold a |
| 223 | * handle reference in obj->handle_count. |
| 224 | */ |
| 225 | mutex_lock(&filp->prime.lock); |
| 226 | if (obj->dma_buf) { |
| 227 | drm_prime_remove_buf_handle_locked(&filp->prime, |
| 228 | obj->dma_buf); |
| 229 | } |
| 230 | mutex_unlock(&filp->prime.lock); |
| 231 | #endif |
| 232 | } |
| 233 | |
| 234 | /** |
| 235 | * drm_gem_object_free - release resources bound to userspace handles |
| 236 | * @obj: GEM object to clean up. |
| 237 | * |
| 238 | * Called after the last handle to the object has been closed |
| 239 | * |
| 240 | * Removes any name for the object. Note that this must be |
| 241 | * called before drm_gem_object_free or we'll be touching |
| 242 | * freed memory |
| 243 | */ |
| 244 | static void drm_gem_object_handle_free(struct drm_gem_object *obj) |
| 245 | { |
| 246 | struct drm_device *dev = obj->dev; |
| 247 | |
| 248 | /* Remove any name for this object */ |
| 249 | if (obj->name) { |
| 250 | idr_remove(&dev->object_name_idr, obj->name); |
| 251 | obj->name = 0; |
| 252 | } |
| 253 | } |
| 254 | |
| 255 | static void drm_gem_object_exported_dma_buf_free(struct drm_gem_object *obj) |
| 256 | { |
| 257 | #ifndef __NetBSD__ |
| 258 | /* Unbreak the reference cycle if we have an exported dma_buf. */ |
| 259 | if (obj->dma_buf) { |
| 260 | dma_buf_put(obj->dma_buf); |
| 261 | obj->dma_buf = NULL; |
| 262 | } |
| 263 | #endif |
| 264 | } |
| 265 | |
| 266 | static void |
| 267 | drm_gem_object_handle_unreference_unlocked(struct drm_gem_object *obj) |
| 268 | { |
| 269 | if (WARN_ON(obj->handle_count == 0)) |
| 270 | return; |
| 271 | |
| 272 | /* |
| 273 | * Must bump handle count first as this may be the last |
| 274 | * ref, in which case the object would disappear before we |
| 275 | * checked for a name |
| 276 | */ |
| 277 | |
| 278 | mutex_lock(&obj->dev->object_name_lock); |
| 279 | if (--obj->handle_count == 0) { |
| 280 | drm_gem_object_handle_free(obj); |
| 281 | drm_gem_object_exported_dma_buf_free(obj); |
| 282 | } |
| 283 | mutex_unlock(&obj->dev->object_name_lock); |
| 284 | |
| 285 | drm_gem_object_unreference_unlocked(obj); |
| 286 | } |
| 287 | |
| 288 | /** |
| 289 | * drm_gem_handle_delete - deletes the given file-private handle |
| 290 | * @filp: drm file-private structure to use for the handle look up |
| 291 | * @handle: userspace handle to delete |
| 292 | * |
| 293 | * Removes the GEM handle from the @filp lookup table and if this is the last |
| 294 | * handle also cleans up linked resources like GEM names. |
| 295 | */ |
| 296 | int |
| 297 | drm_gem_handle_delete(struct drm_file *filp, u32 handle) |
| 298 | { |
| 299 | struct drm_device *dev; |
| 300 | struct drm_gem_object *obj; |
| 301 | |
| 302 | /* This is gross. The idr system doesn't let us try a delete and |
| 303 | * return an error code. It just spews if you fail at deleting. |
| 304 | * So, we have to grab a lock around finding the object and then |
| 305 | * doing the delete on it and dropping the refcount, or the user |
| 306 | * could race us to double-decrement the refcount and cause a |
| 307 | * use-after-free later. Given the frequency of our handle lookups, |
| 308 | * we may want to use ida for number allocation and a hash table |
| 309 | * for the pointers, anyway. |
| 310 | */ |
| 311 | spin_lock(&filp->table_lock); |
| 312 | |
| 313 | /* Check if we currently have a reference on the object */ |
| 314 | obj = idr_find(&filp->object_idr, handle); |
| 315 | if (obj == NULL) { |
| 316 | spin_unlock(&filp->table_lock); |
| 317 | return -EINVAL; |
| 318 | } |
| 319 | dev = obj->dev; |
| 320 | |
| 321 | /* Release reference and decrement refcount. */ |
| 322 | idr_remove(&filp->object_idr, handle); |
| 323 | spin_unlock(&filp->table_lock); |
| 324 | |
| 325 | if (drm_core_check_feature(dev, DRIVER_PRIME)) |
| 326 | drm_gem_remove_prime_handles(obj, filp); |
| 327 | drm_vma_node_revoke(&obj->vma_node, filp->filp); |
| 328 | |
| 329 | if (dev->driver->gem_close_object) |
| 330 | dev->driver->gem_close_object(obj, filp); |
| 331 | drm_gem_object_handle_unreference_unlocked(obj); |
| 332 | |
| 333 | return 0; |
| 334 | } |
| 335 | EXPORT_SYMBOL(drm_gem_handle_delete); |
| 336 | |
| 337 | /** |
| 338 | * drm_gem_dumb_destroy - dumb fb callback helper for gem based drivers |
| 339 | * @file: drm file-private structure to remove the dumb handle from |
| 340 | * @dev: corresponding drm_device |
| 341 | * @handle: the dumb handle to remove |
| 342 | * |
| 343 | * This implements the ->dumb_destroy kms driver callback for drivers which use |
| 344 | * gem to manage their backing storage. |
| 345 | */ |
| 346 | int drm_gem_dumb_destroy(struct drm_file *file, |
| 347 | struct drm_device *dev, |
| 348 | uint32_t handle) |
| 349 | { |
| 350 | return drm_gem_handle_delete(file, handle); |
| 351 | } |
| 352 | EXPORT_SYMBOL(drm_gem_dumb_destroy); |
| 353 | |
| 354 | /** |
| 355 | * drm_gem_handle_create_tail - internal functions to create a handle |
| 356 | * @file_priv: drm file-private structure to register the handle for |
| 357 | * @obj: object to register |
| 358 | * @handlep: pionter to return the created handle to the caller |
| 359 | * |
| 360 | * This expects the dev->object_name_lock to be held already and will drop it |
| 361 | * before returning. Used to avoid races in establishing new handles when |
| 362 | * importing an object from either an flink name or a dma-buf. |
| 363 | */ |
| 364 | int |
| 365 | drm_gem_handle_create_tail(struct drm_file *file_priv, |
| 366 | struct drm_gem_object *obj, |
| 367 | u32 *handlep) |
| 368 | { |
| 369 | struct drm_device *dev = obj->dev; |
| 370 | int ret; |
| 371 | |
| 372 | WARN_ON(!mutex_is_locked(&dev->object_name_lock)); |
| 373 | |
| 374 | /* |
| 375 | * Get the user-visible handle using idr. Preload and perform |
| 376 | * allocation under our spinlock. |
| 377 | */ |
| 378 | idr_preload(GFP_KERNEL); |
| 379 | spin_lock(&file_priv->table_lock); |
| 380 | |
| 381 | ret = idr_alloc(&file_priv->object_idr, obj, 1, 0, GFP_NOWAIT); |
| 382 | drm_gem_object_reference(obj); |
| 383 | obj->handle_count++; |
| 384 | spin_unlock(&file_priv->table_lock); |
| 385 | idr_preload_end(); |
| 386 | mutex_unlock(&dev->object_name_lock); |
| 387 | if (ret < 0) { |
| 388 | drm_gem_object_handle_unreference_unlocked(obj); |
| 389 | return ret; |
| 390 | } |
| 391 | *handlep = ret; |
| 392 | |
| 393 | ret = drm_vma_node_allow(&obj->vma_node, file_priv->filp); |
| 394 | if (ret) { |
| 395 | drm_gem_handle_delete(file_priv, *handlep); |
| 396 | return ret; |
| 397 | } |
| 398 | |
| 399 | if (dev->driver->gem_open_object) { |
| 400 | ret = dev->driver->gem_open_object(obj, file_priv); |
| 401 | if (ret) { |
| 402 | drm_gem_handle_delete(file_priv, *handlep); |
| 403 | return ret; |
| 404 | } |
| 405 | } |
| 406 | |
| 407 | return 0; |
| 408 | } |
| 409 | |
| 410 | /** |
| 411 | * gem_handle_create - create a gem handle for an object |
| 412 | * @file_priv: drm file-private structure to register the handle for |
| 413 | * @obj: object to register |
| 414 | * @handlep: pionter to return the created handle to the caller |
| 415 | * |
| 416 | * Create a handle for this object. This adds a handle reference |
| 417 | * to the object, which includes a regular reference count. Callers |
| 418 | * will likely want to dereference the object afterwards. |
| 419 | */ |
| 420 | int |
| 421 | drm_gem_handle_create(struct drm_file *file_priv, |
| 422 | struct drm_gem_object *obj, |
| 423 | u32 *handlep) |
| 424 | { |
| 425 | mutex_lock(&obj->dev->object_name_lock); |
| 426 | |
| 427 | return drm_gem_handle_create_tail(file_priv, obj, handlep); |
| 428 | } |
| 429 | EXPORT_SYMBOL(drm_gem_handle_create); |
| 430 | |
| 431 | |
| 432 | /** |
| 433 | * drm_gem_free_mmap_offset - release a fake mmap offset for an object |
| 434 | * @obj: obj in question |
| 435 | * |
| 436 | * This routine frees fake offsets allocated by drm_gem_create_mmap_offset(). |
| 437 | */ |
| 438 | void |
| 439 | drm_gem_free_mmap_offset(struct drm_gem_object *obj) |
| 440 | { |
| 441 | struct drm_device *dev = obj->dev; |
| 442 | |
| 443 | drm_vma_offset_remove(dev->vma_offset_manager, &obj->vma_node); |
| 444 | } |
| 445 | EXPORT_SYMBOL(drm_gem_free_mmap_offset); |
| 446 | |
| 447 | /** |
| 448 | * drm_gem_create_mmap_offset_size - create a fake mmap offset for an object |
| 449 | * @obj: obj in question |
| 450 | * @size: the virtual size |
| 451 | * |
| 452 | * GEM memory mapping works by handing back to userspace a fake mmap offset |
| 453 | * it can use in a subsequent mmap(2) call. The DRM core code then looks |
| 454 | * up the object based on the offset and sets up the various memory mapping |
| 455 | * structures. |
| 456 | * |
| 457 | * This routine allocates and attaches a fake offset for @obj, in cases where |
| 458 | * the virtual size differs from the physical size (ie. obj->size). Otherwise |
| 459 | * just use drm_gem_create_mmap_offset(). |
| 460 | */ |
| 461 | int |
| 462 | drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size) |
| 463 | { |
| 464 | struct drm_device *dev = obj->dev; |
| 465 | |
| 466 | return drm_vma_offset_add(dev->vma_offset_manager, &obj->vma_node, |
| 467 | size / PAGE_SIZE); |
| 468 | } |
| 469 | EXPORT_SYMBOL(drm_gem_create_mmap_offset_size); |
| 470 | |
| 471 | /** |
| 472 | * drm_gem_create_mmap_offset - create a fake mmap offset for an object |
| 473 | * @obj: obj in question |
| 474 | * |
| 475 | * GEM memory mapping works by handing back to userspace a fake mmap offset |
| 476 | * it can use in a subsequent mmap(2) call. The DRM core code then looks |
| 477 | * up the object based on the offset and sets up the various memory mapping |
| 478 | * structures. |
| 479 | * |
| 480 | * This routine allocates and attaches a fake offset for @obj. |
| 481 | */ |
| 482 | int drm_gem_create_mmap_offset(struct drm_gem_object *obj) |
| 483 | { |
| 484 | return drm_gem_create_mmap_offset_size(obj, obj->size); |
| 485 | } |
| 486 | EXPORT_SYMBOL(drm_gem_create_mmap_offset); |
| 487 | |
| 488 | /** |
| 489 | * drm_gem_get_pages - helper to allocate backing pages for a GEM object |
| 490 | * from shmem |
| 491 | * @obj: obj in question |
| 492 | * @gfpmask: gfp mask of requested pages |
| 493 | */ |
| 494 | #ifdef __NetBSD__ |
| 495 | struct page ** |
| 496 | drm_gem_get_pages(struct drm_gem_object *obj, gfp_t gfpmask) |
| 497 | { |
| 498 | struct pglist pglist; |
| 499 | struct vm_page *vm_page; |
| 500 | struct page **pages; |
| 501 | unsigned i; |
| 502 | int ret; |
| 503 | |
| 504 | KASSERT((obj->size & (PAGE_SIZE - 1)) != 0); |
| 505 | |
| 506 | pages = drm_malloc_ab(obj->size >> PAGE_SHIFT, sizeof(*pages)); |
| 507 | if (pages == NULL) { |
| 508 | ret = -ENOMEM; |
| 509 | goto fail0; |
| 510 | } |
| 511 | |
| 512 | TAILQ_INIT(&pglist); |
| 513 | /* XXX errno NetBSD->Linux */ |
| 514 | ret = -uvm_obj_wirepages(obj->gemo_shm_uao, 0, obj->size, &pglist); |
| 515 | if (ret) |
| 516 | goto fail1; |
| 517 | |
| 518 | i = 0; |
| 519 | TAILQ_FOREACH(vm_page, &pglist, pageq.queue) |
| 520 | pages[i++] = container_of(vm_page, struct page, p_vmp); |
| 521 | |
| 522 | return pages; |
| 523 | |
| 524 | fail1: drm_free_large(pages); |
| 525 | fail0: return ERR_PTR(ret); |
| 526 | } |
| 527 | #else |
| 528 | struct page **drm_gem_get_pages(struct drm_gem_object *obj, gfp_t gfpmask) |
| 529 | { |
| 530 | struct inode *inode; |
| 531 | struct address_space *mapping; |
| 532 | struct page *p, **pages; |
| 533 | int i, npages; |
| 534 | |
| 535 | /* This is the shared memory object that backs the GEM resource */ |
| 536 | inode = file_inode(obj->filp); |
| 537 | mapping = inode->i_mapping; |
| 538 | |
| 539 | /* We already BUG_ON() for non-page-aligned sizes in |
| 540 | * drm_gem_object_init(), so we should never hit this unless |
| 541 | * driver author is doing something really wrong: |
| 542 | */ |
| 543 | WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0); |
| 544 | |
| 545 | npages = obj->size >> PAGE_SHIFT; |
| 546 | |
| 547 | pages = drm_malloc_ab(npages, sizeof(struct page *)); |
| 548 | if (pages == NULL) |
| 549 | return ERR_PTR(-ENOMEM); |
| 550 | |
| 551 | gfpmask |= mapping_gfp_mask(mapping); |
| 552 | |
| 553 | for (i = 0; i < npages; i++) { |
| 554 | p = shmem_read_mapping_page_gfp(mapping, i, gfpmask); |
| 555 | if (IS_ERR(p)) |
| 556 | goto fail; |
| 557 | pages[i] = p; |
| 558 | |
| 559 | /* There is a hypothetical issue w/ drivers that require |
| 560 | * buffer memory in the low 4GB.. if the pages are un- |
| 561 | * pinned, and swapped out, they can end up swapped back |
| 562 | * in above 4GB. If pages are already in memory, then |
| 563 | * shmem_read_mapping_page_gfp will ignore the gfpmask, |
| 564 | * even if the already in-memory page disobeys the mask. |
| 565 | * |
| 566 | * It is only a theoretical issue today, because none of |
| 567 | * the devices with this limitation can be populated with |
| 568 | * enough memory to trigger the issue. But this BUG_ON() |
| 569 | * is here as a reminder in case the problem with |
| 570 | * shmem_read_mapping_page_gfp() isn't solved by the time |
| 571 | * it does become a real issue. |
| 572 | * |
| 573 | * See this thread: http://lkml.org/lkml/2011/7/11/238 |
| 574 | */ |
| 575 | BUG_ON((gfpmask & __GFP_DMA32) && |
| 576 | (page_to_pfn(p) >= 0x00100000UL)); |
| 577 | } |
| 578 | |
| 579 | return pages; |
| 580 | |
| 581 | fail: |
| 582 | while (i--) |
| 583 | page_cache_release(pages[i]); |
| 584 | |
| 585 | drm_free_large(pages); |
| 586 | return ERR_CAST(p); |
| 587 | } |
| 588 | #endif |
| 589 | EXPORT_SYMBOL(drm_gem_get_pages); |
| 590 | |
| 591 | /** |
| 592 | * drm_gem_put_pages - helper to free backing pages for a GEM object |
| 593 | * @obj: obj in question |
| 594 | * @pages: pages to free |
| 595 | * @dirty: if true, pages will be marked as dirty |
| 596 | * @accessed: if true, the pages will be marked as accessed |
| 597 | */ |
| 598 | #ifdef __NetBSD__ |
| 599 | void |
| 600 | drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages, bool dirty, |
| 601 | bool accessed __unused /* XXX */) |
| 602 | { |
| 603 | unsigned i; |
| 604 | |
| 605 | for (i = 0; i < (obj->size >> PAGE_SHIFT); i++) { |
| 606 | if (dirty) |
| 607 | pages[i]->p_vmp.flags &= ~PG_CLEAN; |
| 608 | } |
| 609 | |
| 610 | uvm_obj_unwirepages(obj->gemo_shm_uao, 0, obj->size); |
| 611 | } |
| 612 | #else |
| 613 | void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages, |
| 614 | bool dirty, bool accessed) |
| 615 | { |
| 616 | int i, npages; |
| 617 | |
| 618 | /* We already BUG_ON() for non-page-aligned sizes in |
| 619 | * drm_gem_object_init(), so we should never hit this unless |
| 620 | * driver author is doing something really wrong: |
| 621 | */ |
| 622 | WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0); |
| 623 | |
| 624 | npages = obj->size >> PAGE_SHIFT; |
| 625 | |
| 626 | for (i = 0; i < npages; i++) { |
| 627 | if (dirty) |
| 628 | set_page_dirty(pages[i]); |
| 629 | |
| 630 | if (accessed) |
| 631 | mark_page_accessed(pages[i]); |
| 632 | |
| 633 | /* Undo the reference we took when populating the table */ |
| 634 | page_cache_release(pages[i]); |
| 635 | } |
| 636 | |
| 637 | drm_free_large(pages); |
| 638 | } |
| 639 | #endif |
| 640 | EXPORT_SYMBOL(drm_gem_put_pages); |
| 641 | |
| 642 | /** Returns a reference to the object named by the handle. */ |
| 643 | struct drm_gem_object * |
| 644 | drm_gem_object_lookup(struct drm_device *dev, struct drm_file *filp, |
| 645 | u32 handle) |
| 646 | { |
| 647 | struct drm_gem_object *obj; |
| 648 | |
| 649 | spin_lock(&filp->table_lock); |
| 650 | |
| 651 | /* Check if we currently have a reference on the object */ |
| 652 | obj = idr_find(&filp->object_idr, handle); |
| 653 | if (obj == NULL) { |
| 654 | spin_unlock(&filp->table_lock); |
| 655 | return NULL; |
| 656 | } |
| 657 | |
| 658 | drm_gem_object_reference(obj); |
| 659 | |
| 660 | spin_unlock(&filp->table_lock); |
| 661 | |
| 662 | return obj; |
| 663 | } |
| 664 | EXPORT_SYMBOL(drm_gem_object_lookup); |
| 665 | |
| 666 | /** |
| 667 | * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl |
| 668 | * @dev: drm_device |
| 669 | * @data: ioctl data |
| 670 | * @file_priv: drm file-private structure |
| 671 | * |
| 672 | * Releases the handle to an mm object. |
| 673 | */ |
| 674 | int |
| 675 | drm_gem_close_ioctl(struct drm_device *dev, void *data, |
| 676 | struct drm_file *file_priv) |
| 677 | { |
| 678 | struct drm_gem_close *args = data; |
| 679 | int ret; |
| 680 | |
| 681 | if (!(dev->driver->driver_features & DRIVER_GEM)) |
| 682 | return -ENODEV; |
| 683 | |
| 684 | ret = drm_gem_handle_delete(file_priv, args->handle); |
| 685 | |
| 686 | return ret; |
| 687 | } |
| 688 | |
| 689 | /** |
| 690 | * drm_gem_flink_ioctl - implementation of the GEM_FLINK ioctl |
| 691 | * @dev: drm_device |
| 692 | * @data: ioctl data |
| 693 | * @file_priv: drm file-private structure |
| 694 | * |
| 695 | * Create a global name for an object, returning the name. |
| 696 | * |
| 697 | * Note that the name does not hold a reference; when the object |
| 698 | * is freed, the name goes away. |
| 699 | */ |
| 700 | int |
| 701 | drm_gem_flink_ioctl(struct drm_device *dev, void *data, |
| 702 | struct drm_file *file_priv) |
| 703 | { |
| 704 | struct drm_gem_flink *args = data; |
| 705 | struct drm_gem_object *obj; |
| 706 | int ret; |
| 707 | |
| 708 | if (!(dev->driver->driver_features & DRIVER_GEM)) |
| 709 | return -ENODEV; |
| 710 | |
| 711 | obj = drm_gem_object_lookup(dev, file_priv, args->handle); |
| 712 | if (obj == NULL) |
| 713 | return -ENOENT; |
| 714 | |
| 715 | mutex_lock(&dev->object_name_lock); |
| 716 | idr_preload(GFP_KERNEL); |
| 717 | /* prevent races with concurrent gem_close. */ |
| 718 | if (obj->handle_count == 0) { |
| 719 | ret = -ENOENT; |
| 720 | goto err; |
| 721 | } |
| 722 | |
| 723 | if (!obj->name) { |
| 724 | ret = idr_alloc(&dev->object_name_idr, obj, 1, 0, GFP_NOWAIT); |
| 725 | if (ret < 0) |
| 726 | goto err; |
| 727 | |
| 728 | obj->name = ret; |
| 729 | } |
| 730 | |
| 731 | args->name = (uint64_t) obj->name; |
| 732 | ret = 0; |
| 733 | |
| 734 | err: |
| 735 | idr_preload_end(); |
| 736 | mutex_unlock(&dev->object_name_lock); |
| 737 | drm_gem_object_unreference_unlocked(obj); |
| 738 | return ret; |
| 739 | } |
| 740 | |
| 741 | /** |
| 742 | * drm_gem_open - implementation of the GEM_OPEN ioctl |
| 743 | * @dev: drm_device |
| 744 | * @data: ioctl data |
| 745 | * @file_priv: drm file-private structure |
| 746 | * |
| 747 | * Open an object using the global name, returning a handle and the size. |
| 748 | * |
| 749 | * This handle (of course) holds a reference to the object, so the object |
| 750 | * will not go away until the handle is deleted. |
| 751 | */ |
| 752 | int |
| 753 | drm_gem_open_ioctl(struct drm_device *dev, void *data, |
| 754 | struct drm_file *file_priv) |
| 755 | { |
| 756 | struct drm_gem_open *args = data; |
| 757 | struct drm_gem_object *obj; |
| 758 | int ret; |
| 759 | u32 handle; |
| 760 | |
| 761 | if (!(dev->driver->driver_features & DRIVER_GEM)) |
| 762 | return -ENODEV; |
| 763 | |
| 764 | mutex_lock(&dev->object_name_lock); |
| 765 | obj = idr_find(&dev->object_name_idr, (int) args->name); |
| 766 | if (obj) { |
| 767 | drm_gem_object_reference(obj); |
| 768 | } else { |
| 769 | mutex_unlock(&dev->object_name_lock); |
| 770 | return -ENOENT; |
| 771 | } |
| 772 | |
| 773 | /* drm_gem_handle_create_tail unlocks dev->object_name_lock. */ |
| 774 | ret = drm_gem_handle_create_tail(file_priv, obj, &handle); |
| 775 | drm_gem_object_unreference_unlocked(obj); |
| 776 | if (ret) |
| 777 | return ret; |
| 778 | |
| 779 | args->handle = handle; |
| 780 | args->size = obj->size; |
| 781 | |
| 782 | return 0; |
| 783 | } |
| 784 | |
| 785 | /** |
| 786 | * gem_gem_open - initalizes GEM file-private structures at devnode open time |
| 787 | * @dev: drm_device which is being opened by userspace |
| 788 | * @file_private: drm file-private structure to set up |
| 789 | * |
| 790 | * Called at device open time, sets up the structure for handling refcounting |
| 791 | * of mm objects. |
| 792 | */ |
| 793 | void |
| 794 | drm_gem_open(struct drm_device *dev, struct drm_file *file_private) |
| 795 | { |
| 796 | idr_init(&file_private->object_idr); |
| 797 | spin_lock_init(&file_private->table_lock); |
| 798 | } |
| 799 | |
| 800 | /* |
| 801 | * Called at device close to release the file's |
| 802 | * handle references on objects. |
| 803 | */ |
| 804 | static int |
| 805 | drm_gem_object_release_handle(int id, void *ptr, void *data) |
| 806 | { |
| 807 | struct drm_file *file_priv = data; |
| 808 | struct drm_gem_object *obj = ptr; |
| 809 | struct drm_device *dev = obj->dev; |
| 810 | |
| 811 | #ifndef __NetBSD__ /* XXX drm prime */ |
| 812 | if (drm_core_check_feature(dev, DRIVER_PRIME)) |
| 813 | drm_gem_remove_prime_handles(obj, file_priv); |
| 814 | #endif |
| 815 | drm_vma_node_revoke(&obj->vma_node, file_priv->filp); |
| 816 | |
| 817 | if (dev->driver->gem_close_object) |
| 818 | dev->driver->gem_close_object(obj, file_priv); |
| 819 | |
| 820 | drm_gem_object_handle_unreference_unlocked(obj); |
| 821 | |
| 822 | return 0; |
| 823 | } |
| 824 | |
| 825 | /** |
| 826 | * drm_gem_release - release file-private GEM resources |
| 827 | * @dev: drm_device which is being closed by userspace |
| 828 | * @file_private: drm file-private structure to clean up |
| 829 | * |
| 830 | * Called at close time when the filp is going away. |
| 831 | * |
| 832 | * Releases any remaining references on objects by this filp. |
| 833 | */ |
| 834 | void |
| 835 | drm_gem_release(struct drm_device *dev, struct drm_file *file_private) |
| 836 | { |
| 837 | idr_for_each(&file_private->object_idr, |
| 838 | &drm_gem_object_release_handle, file_private); |
| 839 | idr_destroy(&file_private->object_idr); |
| 840 | #ifdef __NetBSD__ |
| 841 | spin_lock_destroy(&file_private->table_lock); |
| 842 | #endif |
| 843 | } |
| 844 | |
| 845 | void |
| 846 | drm_gem_object_release(struct drm_gem_object *obj) |
| 847 | { |
| 848 | #ifndef __NetBSD__ |
| 849 | WARN_ON(obj->dma_buf); |
| 850 | #endif |
| 851 | |
| 852 | #ifdef __NetBSD__ |
| 853 | drm_vma_node_destroy(&obj->vma_node); |
| 854 | if (obj->gemo_shm_uao) |
| 855 | uao_detach(obj->gemo_shm_uao); |
| 856 | uvm_obj_destroy(&obj->gemo_uvmobj, true); |
| 857 | #else |
| 858 | if (obj->filp) |
| 859 | fput(obj->filp); |
| 860 | #endif |
| 861 | |
| 862 | drm_gem_free_mmap_offset(obj); |
| 863 | } |
| 864 | EXPORT_SYMBOL(drm_gem_object_release); |
| 865 | |
| 866 | /** |
| 867 | * drm_gem_object_free - free a GEM object |
| 868 | * @kref: kref of the object to free |
| 869 | * |
| 870 | * Called after the last reference to the object has been lost. |
| 871 | * Must be called holding struct_ mutex |
| 872 | * |
| 873 | * Frees the object |
| 874 | */ |
| 875 | void |
| 876 | drm_gem_object_free(struct kref *kref) |
| 877 | { |
| 878 | struct drm_gem_object *obj = (struct drm_gem_object *) kref; |
| 879 | struct drm_device *dev = obj->dev; |
| 880 | |
| 881 | BUG_ON(!mutex_is_locked(&dev->struct_mutex)); |
| 882 | |
| 883 | if (dev->driver->gem_free_object != NULL) |
| 884 | dev->driver->gem_free_object(obj); |
| 885 | } |
| 886 | EXPORT_SYMBOL(drm_gem_object_free); |
| 887 | |
| 888 | #ifndef __NetBSD__ |
| 889 | |
| 890 | void drm_gem_vm_open(struct vm_area_struct *vma) |
| 891 | { |
| 892 | struct drm_gem_object *obj = vma->vm_private_data; |
| 893 | |
| 894 | drm_gem_object_reference(obj); |
| 895 | |
| 896 | mutex_lock(&obj->dev->struct_mutex); |
| 897 | drm_vm_open_locked(obj->dev, vma); |
| 898 | mutex_unlock(&obj->dev->struct_mutex); |
| 899 | } |
| 900 | EXPORT_SYMBOL(drm_gem_vm_open); |
| 901 | |
| 902 | void drm_gem_vm_close(struct vm_area_struct *vma) |
| 903 | { |
| 904 | struct drm_gem_object *obj = vma->vm_private_data; |
| 905 | struct drm_device *dev = obj->dev; |
| 906 | |
| 907 | mutex_lock(&dev->struct_mutex); |
| 908 | drm_vm_close_locked(obj->dev, vma); |
| 909 | drm_gem_object_unreference(obj); |
| 910 | mutex_unlock(&dev->struct_mutex); |
| 911 | } |
| 912 | EXPORT_SYMBOL(drm_gem_vm_close); |
| 913 | |
| 914 | /** |
| 915 | * drm_gem_mmap_obj - memory map a GEM object |
| 916 | * @obj: the GEM object to map |
| 917 | * @obj_size: the object size to be mapped, in bytes |
| 918 | * @vma: VMA for the area to be mapped |
| 919 | * |
| 920 | * Set up the VMA to prepare mapping of the GEM object using the gem_vm_ops |
| 921 | * provided by the driver. Depending on their requirements, drivers can either |
| 922 | * provide a fault handler in their gem_vm_ops (in which case any accesses to |
| 923 | * the object will be trapped, to perform migration, GTT binding, surface |
| 924 | * register allocation, or performance monitoring), or mmap the buffer memory |
| 925 | * synchronously after calling drm_gem_mmap_obj. |
| 926 | * |
| 927 | * This function is mainly intended to implement the DMABUF mmap operation, when |
| 928 | * the GEM object is not looked up based on its fake offset. To implement the |
| 929 | * DRM mmap operation, drivers should use the drm_gem_mmap() function. |
| 930 | * |
| 931 | * drm_gem_mmap_obj() assumes the user is granted access to the buffer while |
| 932 | * drm_gem_mmap() prevents unprivileged users from mapping random objects. So |
| 933 | * callers must verify access restrictions before calling this helper. |
| 934 | * |
| 935 | * NOTE: This function has to be protected with dev->struct_mutex |
| 936 | * |
| 937 | * Return 0 or success or -EINVAL if the object size is smaller than the VMA |
| 938 | * size, or if no gem_vm_ops are provided. |
| 939 | */ |
| 940 | int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size, |
| 941 | struct vm_area_struct *vma) |
| 942 | { |
| 943 | struct drm_device *dev = obj->dev; |
| 944 | |
| 945 | lockdep_assert_held(&dev->struct_mutex); |
| 946 | |
| 947 | /* Check for valid size. */ |
| 948 | if (obj_size < vma->vm_end - vma->vm_start) |
| 949 | return -EINVAL; |
| 950 | |
| 951 | if (!dev->driver->gem_vm_ops) |
| 952 | return -EINVAL; |
| 953 | |
| 954 | vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP; |
| 955 | vma->vm_ops = dev->driver->gem_vm_ops; |
| 956 | vma->vm_private_data = obj; |
| 957 | vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); |
| 958 | |
| 959 | /* Take a ref for this mapping of the object, so that the fault |
| 960 | * handler can dereference the mmap offset's pointer to the object. |
| 961 | * This reference is cleaned up by the corresponding vm_close |
| 962 | * (which should happen whether the vma was created by this call, or |
| 963 | * by a vm_open due to mremap or partial unmap or whatever). |
| 964 | */ |
| 965 | drm_gem_object_reference(obj); |
| 966 | |
| 967 | drm_vm_open_locked(dev, vma); |
| 968 | return 0; |
| 969 | } |
| 970 | EXPORT_SYMBOL(drm_gem_mmap_obj); |
| 971 | |
| 972 | /** |
| 973 | * drm_gem_mmap - memory map routine for GEM objects |
| 974 | * @filp: DRM file pointer |
| 975 | * @vma: VMA for the area to be mapped |
| 976 | * |
| 977 | * If a driver supports GEM object mapping, mmap calls on the DRM file |
| 978 | * descriptor will end up here. |
| 979 | * |
| 980 | * Look up the GEM object based on the offset passed in (vma->vm_pgoff will |
| 981 | * contain the fake offset we created when the GTT map ioctl was called on |
| 982 | * the object) and map it with a call to drm_gem_mmap_obj(). |
| 983 | * |
| 984 | * If the caller is not granted access to the buffer object, the mmap will fail |
| 985 | * with EACCES. Please see the vma manager for more information. |
| 986 | */ |
| 987 | int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma) |
| 988 | { |
| 989 | struct drm_file *priv = filp->private_data; |
| 990 | struct drm_device *dev = priv->minor->dev; |
| 991 | struct drm_gem_object *obj; |
| 992 | struct drm_vma_offset_node *node; |
| 993 | int ret; |
| 994 | |
| 995 | if (drm_device_is_unplugged(dev)) |
| 996 | return -ENODEV; |
| 997 | |
| 998 | mutex_lock(&dev->struct_mutex); |
| 999 | |
| 1000 | node = drm_vma_offset_exact_lookup(dev->vma_offset_manager, |
| 1001 | vma->vm_pgoff, |
| 1002 | vma_pages(vma)); |
| 1003 | if (!node) { |
| 1004 | mutex_unlock(&dev->struct_mutex); |
| 1005 | return drm_mmap(filp, vma); |
| 1006 | } else if (!drm_vma_node_is_allowed(node, filp)) { |
| 1007 | mutex_unlock(&dev->struct_mutex); |
| 1008 | return -EACCES; |
| 1009 | } |
| 1010 | |
| 1011 | obj = container_of(node, struct drm_gem_object, vma_node); |
| 1012 | ret = drm_gem_mmap_obj(obj, drm_vma_node_size(node) << PAGE_SHIFT, vma); |
| 1013 | |
| 1014 | mutex_unlock(&dev->struct_mutex); |
| 1015 | |
| 1016 | return ret; |
| 1017 | } |
| 1018 | EXPORT_SYMBOL(drm_gem_mmap); |
| 1019 | |
| 1020 | #endif /* defined(__NetBSD__) */ |
| 1021 | |