include/drm/drm_gem.h

   1 #ifndef __DRM_GEM_H__
   2 #define __DRM_GEM_H__
   3
   4 /*
   5  * GEM Graphics Execution Manager Driver Interfaces
   6  *
   7  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
   8  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
   9  * Copyright (c) 2009-2010, Code Aurora Forum.
  10  * All rights reserved.
  11  * Copyright © 2014 Intel Corporation
  12  *   Daniel Vetter <daniel.vetter@ffwll.ch>
  13  *
  14  * Author: Rickard E. (Rik) Faith <faith@valinux.com>
  15  * Author: Gareth Hughes <gareth@valinux.com>
  16  *
  17  * Permission is hereby granted, free of charge, to any person obtaining a
  18  * copy of this software and associated documentation files (the "Software"),
  19  * to deal in the Software without restriction, including without limitation
  20  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  21  * and/or sell copies of the Software, and to permit persons to whom the
  22  * Software is furnished to do so, subject to the following conditions:
  23  *
  24  * The above copyright notice and this permission notice (including the next
  25  * paragraph) shall be included in all copies or substantial portions of the
  26  * Software.
  27  *
  28  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  29  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  30  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  31  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  32  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  33  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  34  * OTHER DEALINGS IN THE SOFTWARE.
  35  */
  36
  37 #include <linux/kref.h>
  38 #include <linux/dma-resv.h>
  39
  40 #include <drm/drm_vma_manager.h>
  41
  42 struct drm_gem_object;
  43
  44 /**
  45  * struct drm_gem_object_funcs - GEM object functions
  46  */
  47 struct drm_gem_object_funcs {
  48         /**
  49          * @free:
  50          *
  51          * Deconstructor for drm_gem_objects.
  52          *
  53          * This callback is mandatory.
  54          */
  55         void (*free)(struct drm_gem_object *obj);
  56
  57         /**
  58          * @open:
  59          *
  60          * Called upon GEM handle creation.
  61          *
  62          * This callback is optional.
  63          */
  64         int (*open)(struct drm_gem_object *obj, struct drm_file *file);
  65
  66         /**
  67          * @close:
  68          *
  69          * Called upon GEM handle release.
  70          *
  71          * This callback is optional.
  72          */
  73         void (*close)(struct drm_gem_object *obj, struct drm_file *file);
  74
  75         /**
  76          * @print_info:
  77          *
  78          * If driver subclasses struct &drm_gem_object, it can implement this
  79          * optional hook for printing additional driver specific info.
  80          *
  81          * drm_printf_indent() should be used in the callback passing it the
  82          * indent argument.
  83          *
  84          * This callback is called from drm_gem_print_info().
  85          *
  86          * This callback is optional.
  87          */
  88         void (*print_info)(struct drm_printer *p, unsigned int indent,
  89                            const struct drm_gem_object *obj);
  90
  91         /**
  92          * @export:
  93          *
  94          * Export backing buffer as a &dma_buf.
  95          * If this is not set drm_gem_prime_export() is used.
  96          *
  97          * This callback is optional.
  98          */
  99         struct dma_buf *(*export)(struct drm_gem_object *obj, int flags);
 100
 101         /**
 102          * @pin:
 103          *
 104          * Pin backing buffer in memory. Used by the drm_gem_map_attach() helper.
 105          *
 106          * This callback is optional.
 107          */
 108         int (*pin)(struct drm_gem_object *obj);
 109
 110         /**
 111          * @unpin:
 112          *
 113          * Unpin backing buffer. Used by the drm_gem_map_detach() helper.
 114          *
 115          * This callback is optional.
 116          */
 117         void (*unpin)(struct drm_gem_object *obj);
 118
 119         /**
 120          * @get_sg_table:
 121          *
 122          * Returns a Scatter-Gather table representation of the buffer.
 123          * Used when exporting a buffer by the drm_gem_map_dma_buf() helper.
 124          * Releasing is done by calling dma_unmap_sg_attrs() and sg_free_table()
 125          * in drm_gem_unmap_buf(), therefore these helpers and this callback
 126          * here cannot be used for sg tables pointing at driver private memory
 127          * ranges.
 128          *
 129          * See also drm_prime_pages_to_sg().
 130          */
 131         struct sg_table *(*get_sg_table)(struct drm_gem_object *obj);
 132
 133         /**
 134          * @vmap:
 135          *
 136          * Returns a virtual address for the buffer. Used by the
 137          * drm_gem_dmabuf_vmap() helper.
 138          *
 139          * This callback is optional.
 140          */
 141         void *(*vmap)(struct drm_gem_object *obj);
 142
 143         /**
 144          * @vunmap:
 145          *
 146          * Releases the the address previously returned by @vmap. Used by the
 147          * drm_gem_dmabuf_vunmap() helper.
 148          *
 149          * This callback is optional.
 150          */
 151         void (*vunmap)(struct drm_gem_object *obj, void *vaddr);
 152
 153         /**
 154          * @mmap:
 155          *
 156          * Handle mmap() of the gem object, setup vma accordingly.
 157          *
 158          * This callback is optional.
 159          *
 160          * The callback is used by by both drm_gem_mmap_obj() and
 161          * drm_gem_prime_mmap().  When @mmap is present @vm_ops is not
 162          * used, the @mmap callback must set vma->vm_ops instead.
 163          */
 164         int (*mmap)(struct drm_gem_object *obj, struct vm_area_struct *vma);
 165
 166         /**
 167          * @vm_ops:
 168          *
 169          * Virtual memory operations used with mmap.
 170          *
 171          * This is optional but necessary for mmap support.
 172          */
 173         const struct vm_operations_struct *vm_ops;
 174 };
 175
 176 /**
 177  * struct drm_gem_object - GEM buffer object
 178  *
 179  * This structure defines the generic parts for GEM buffer objects, which are
 180  * mostly around handling mmap and userspace handles.
 181  *
 182  * Buffer objects are often abbreviated to BO.
 183  */
 184 struct drm_gem_object {
 185         /**
 186          * @refcount:
 187          *
 188          * Reference count of this object
 189          *
 190          * Please use drm_gem_object_get() to acquire and drm_gem_object_put()
 191          * or drm_gem_object_put_unlocked() to release a reference to a GEM
 192          * buffer object.
 193          */
 194         struct kref refcount;
 195
 196         /**
 197          * @handle_count:
 198          *
 199          * This is the GEM file_priv handle count of this object.
 200          *
 201          * Each handle also holds a reference. Note that when the handle_count
 202          * drops to 0 any global names (e.g. the id in the flink namespace) will
 203          * be cleared.
 204          *
 205          * Protected by &drm_device.object_name_lock.
 206          */
 207         unsigned handle_count;
 208
 209         /**
 210          * @dev: DRM dev this object belongs to.
 211          */
 212         struct drm_device *dev;
 213
 214         /**
 215          * @filp:
 216          *
 217          * SHMEM file node used as backing storage for swappable buffer objects.
 218          * GEM also supports driver private objects with driver-specific backing
 219          * storage (contiguous CMA memory, special reserved blocks). In this
 220          * case @filp is NULL.
 221          */
 222         struct file *filp;
 223
 224         /**
 225          * @vma_node:
 226          *
 227          * Mapping info for this object to support mmap. Drivers are supposed to
 228          * allocate the mmap offset using drm_gem_create_mmap_offset(). The
 229          * offset itself can be retrieved using drm_vma_node_offset_addr().
 230          *
 231          * Memory mapping itself is handled by drm_gem_mmap(), which also checks
 232          * that userspace is allowed to access the object.
 233          */
 234         struct drm_vma_offset_node vma_node;
 235
 236         /**
 237          * @size:
 238          *
 239          * Size of the object, in bytes.  Immutable over the object's
 240          * lifetime.
 241          */
 242         size_t size;
 243
 244         /**
 245          * @name:
 246          *
 247          * Global name for this object, starts at 1. 0 means unnamed.
 248          * Access is covered by &drm_device.object_name_lock. This is used by
 249          * the GEM_FLINK and GEM_OPEN ioctls.
 250          */
 251         int name;
 252
 253         /**
 254          * @dma_buf:
 255          *
 256          * dma-buf associated with this GEM object.
 257          *
 258          * Pointer to the dma-buf associated with this gem object (either
 259          * through importing or exporting). We break the resulting reference
 260          * loop when the last gem handle for this object is released.
 261          *
 262          * Protected by &drm_device.object_name_lock.
 263          */
 264         struct dma_buf *dma_buf;
 265
 266         /**
 267          * @import_attach:
 268          *
 269          * dma-buf attachment backing this object.
 270          *
 271          * Any foreign dma_buf imported as a gem object has this set to the
 272          * attachment point for the device. This is invariant over the lifetime
 273          * of a gem object.
 274          *
 275          * The &drm_driver.gem_free_object callback is responsible for cleaning
 276          * up the dma_buf attachment and references acquired at import time.
 277          *
 278          * Note that the drm gem/prime core does not depend upon drivers setting
 279          * this field any more. So for drivers where this doesn't make sense
 280          * (e.g. virtual devices or a displaylink behind an usb bus) they can
 281          * simply leave it as NULL.
 282          */
 283         struct dma_buf_attachment *import_attach;
 284
 285         /**
 286          * @resv:
 287          *
 288          * Pointer to reservation object associated with the this GEM object.
 289          *
 290          * Normally (@resv == &@_resv) except for imported GEM objects.
 291          */
 292         struct dma_resv *resv;
 293
 294         /**
 295          * @_resv:
 296          *
 297          * A reservation object for this GEM object.
 298          *
 299          * This is unused for imported GEM objects.
 300          */
 301         struct dma_resv _resv;
 302
 303         /**
 304          * @funcs:
 305          *
 306          * Optional GEM object functions. If this is set, it will be used instead of the
 307          * corresponding &drm_driver GEM callbacks.
 308          *
 309          * New drivers should use this.
 310          *
 311          */
 312         const struct drm_gem_object_funcs *funcs;
 313 };
 314
 315 /**
 316  * DEFINE_DRM_GEM_FOPS() - macro to generate file operations for GEM drivers
 317  * @name: name for the generated structure
 318  *
 319  * This macro autogenerates a suitable &struct file_operations for GEM based
 320  * drivers, which can be assigned to &drm_driver.fops. Note that this structure
 321  * cannot be shared between drivers, because it contains a reference to the
 322  * current module using THIS_MODULE.
 323  *
 324  * Note that the declaration is already marked as static - if you need a
 325  * non-static version of this you're probably doing it wrong and will break the
 326  * THIS_MODULE reference by accident.
 327  */
 328 #define DEFINE_DRM_GEM_FOPS(name) \
 329         static const struct file_operations name = {\
 330                 .owner          = THIS_MODULE,\
 331                 .open           = drm_open,\
 332                 .release        = drm_release,\
 333                 .unlocked_ioctl = drm_ioctl,\
 334                 .compat_ioctl   = drm_compat_ioctl,\
 335                 .poll           = drm_poll,\
 336                 .read           = drm_read,\
 337                 .llseek         = noop_llseek,\
 338                 .mmap           = drm_gem_mmap,\
 339         }
 340
 341 void drm_gem_object_release(struct drm_gem_object *obj);
 342 void drm_gem_object_free(struct kref *kref);
 343 int drm_gem_object_init(struct drm_device *dev,
 344                         struct drm_gem_object *obj, size_t size);
 345 void drm_gem_private_object_init(struct drm_device *dev,
 346                                  struct drm_gem_object *obj, size_t size);
 347 void drm_gem_vm_open(struct vm_area_struct *vma);
 348 void drm_gem_vm_close(struct vm_area_struct *vma);
 349 int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
 350                      struct vm_area_struct *vma);
 351 int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma);
 352
 353 /**
 354  * drm_gem_object_get - acquire a GEM buffer object reference
 355  * @obj: GEM buffer object
 356  *
 357  * This function acquires an additional reference to @obj. It is illegal to
 358  * call this without already holding a reference. No locks required.
 359  */
 360 static inline void drm_gem_object_get(struct drm_gem_object *obj)
 361 {
 362         kref_get(&obj->refcount);
 363 }
 364
 365 /**
 366  * __drm_gem_object_put - raw function to release a GEM buffer object reference
 367  * @obj: GEM buffer object
 368  *
 369  * This function is meant to be used by drivers which are not encumbered with
 370  * &drm_device.struct_mutex legacy locking and which are using the
 371  * gem_free_object_unlocked callback. It avoids all the locking checks and
 372  * locking overhead of drm_gem_object_put() and drm_gem_object_put_unlocked().
 373  *
 374  * Drivers should never call this directly in their code. Instead they should
 375  * wrap it up into a ``driver_gem_object_put(struct driver_gem_object *obj)``
 376  * wrapper function, and use that. Shared code should never call this, to
 377  * avoid breaking drivers by accident which still depend upon
 378  * &drm_device.struct_mutex locking.
 379  */
 380 static inline void
 381 __drm_gem_object_put(struct drm_gem_object *obj)
 382 {
 383         kref_put(&obj->refcount, drm_gem_object_free);
 384 }
 385
 386 void drm_gem_object_put_unlocked(struct drm_gem_object *obj);
 387 void drm_gem_object_put(struct drm_gem_object *obj);
 388
 389 int drm_gem_handle_create(struct drm_file *file_priv,
 390                           struct drm_gem_object *obj,
 391                           u32 *handlep);
 392 int drm_gem_handle_delete(struct drm_file *filp, u32 handle);
 393
 394
 395 void drm_gem_free_mmap_offset(struct drm_gem_object *obj);
 396 int drm_gem_create_mmap_offset(struct drm_gem_object *obj);
 397 int drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size);
 398
 399 struct page **drm_gem_get_pages(struct drm_gem_object *obj);
 400 void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
 401                 bool dirty, bool accessed);
 402
 403 int drm_gem_objects_lookup(struct drm_file *filp, void __user *bo_handles,
 404                            int count, struct drm_gem_object ***objs_out);
 405 struct drm_gem_object *drm_gem_object_lookup(struct drm_file *filp, u32 handle);
 406 long drm_gem_dma_resv_wait(struct drm_file *filep, u32 handle,
 407                                     bool wait_all, unsigned long timeout);
 408 int drm_gem_lock_reservations(struct drm_gem_object **objs, int count,
 409                               struct ww_acquire_ctx *acquire_ctx);
 410 void drm_gem_unlock_reservations(struct drm_gem_object **objs, int count,
 411                                  struct ww_acquire_ctx *acquire_ctx);
 412 int drm_gem_fence_array_add(struct xarray *fence_array,
 413                             struct dma_fence *fence);
 414 int drm_gem_fence_array_add_implicit(struct xarray *fence_array,
 415                                      struct drm_gem_object *obj,
 416                                      bool write);
 417 int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
 418                             u32 handle, u64 *offset);
 419 int drm_gem_dumb_destroy(struct drm_file *file,
 420                          struct drm_device *dev,
 421                          uint32_t handle);
 422
 423 #endif /* __DRM_GEM_H__ */