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 dma_buf_map;
  43 struct drm_gem_object;
  44
  45 /**
  46  * struct drm_gem_object_funcs - GEM object functions
  47  */
  48 struct drm_gem_object_funcs {
  49         /**
  50          * @free:
  51          *
  52          * Deconstructor for drm_gem_objects.
  53          *
  54          * This callback is mandatory.
  55          */
  56         void (*free)(struct drm_gem_object *obj);
  57
  58         /**
  59          * @open:
  60          *
  61          * Called upon GEM handle creation.
  62          *
  63          * This callback is optional.
  64          */
  65         int (*open)(struct drm_gem_object *obj, struct drm_file *file);
  66
  67         /**
  68          * @close:
  69          *
  70          * Called upon GEM handle release.
  71          *
  72          * This callback is optional.
  73          */
  74         void (*close)(struct drm_gem_object *obj, struct drm_file *file);
  75
  76         /**
  77          * @print_info:
  78          *
  79          * If driver subclasses struct &drm_gem_object, it can implement this
  80          * optional hook for printing additional driver specific info.
  81          *
  82          * drm_printf_indent() should be used in the callback passing it the
  83          * indent argument.
  84          *
  85          * This callback is called from drm_gem_print_info().
  86          *
  87          * This callback is optional.
  88          */
  89         void (*print_info)(struct drm_printer *p, unsigned int indent,
  90                            const struct drm_gem_object *obj);
  91
  92         /**
  93          * @export:
  94          *
  95          * Export backing buffer as a &dma_buf.
  96          * If this is not set drm_gem_prime_export() is used.
  97          *
  98          * This callback is optional.
  99          */
 100         struct dma_buf *(*export)(struct drm_gem_object *obj, int flags);
 101
 102         /**
 103          * @pin:
 104          *
 105          * Pin backing buffer in memory. Used by the drm_gem_map_attach() helper.
 106          *
 107          * This callback is optional.
 108          */
 109         int (*pin)(struct drm_gem_object *obj);
 110
 111         /**
 112          * @unpin:
 113          *
 114          * Unpin backing buffer. Used by the drm_gem_map_detach() helper.
 115          *
 116          * This callback is optional.
 117          */
 118         void (*unpin)(struct drm_gem_object *obj);
 119
 120         /**
 121          * @get_sg_table:
 122          *
 123          * Returns a Scatter-Gather table representation of the buffer.
 124          * Used when exporting a buffer by the drm_gem_map_dma_buf() helper.
 125          * Releasing is done by calling dma_unmap_sg_attrs() and sg_free_table()
 126          * in drm_gem_unmap_buf(), therefore these helpers and this callback
 127          * here cannot be used for sg tables pointing at driver private memory
 128          * ranges.
 129          *
 130          * See also drm_prime_pages_to_sg().
 131          */
 132         struct sg_table *(*get_sg_table)(struct drm_gem_object *obj);
 133
 134         /**
 135          * @vmap:
 136          *
 137          * Returns a virtual address for the buffer. Used by the
 138          * drm_gem_dmabuf_vmap() helper.
 139          *
 140          * This callback is optional.
 141          */
 142         int (*vmap)(struct drm_gem_object *obj, struct dma_buf_map *map);
 143
 144         /**
 145          * @vunmap:
 146          *
 147          * Releases the address previously returned by @vmap. Used by the
 148          * drm_gem_dmabuf_vunmap() helper.
 149          *
 150          * This callback is optional.
 151          */
 152         void (*vunmap)(struct drm_gem_object *obj, struct dma_buf_map *map);
 153
 154         /**
 155          * @mmap:
 156          *
 157          * Handle mmap() of the gem object, setup vma accordingly.
 158          *
 159          * This callback is optional.
 160          *
 161          * The callback is used by both drm_gem_mmap_obj() and
 162          * drm_gem_prime_mmap().  When @mmap is present @vm_ops is not
 163          * used, the @mmap callback must set vma->vm_ops instead.
 164          */
 165         int (*mmap)(struct drm_gem_object *obj, struct vm_area_struct *vma);
 166
 167         /**
 168          * @vm_ops:
 169          *
 170          * Virtual memory operations used with mmap.
 171          *
 172          * This is optional but necessary for mmap support.
 173          */
 174         const struct vm_operations_struct *vm_ops;
 175 };
 176
 177 /**
 178  * struct drm_gem_object - GEM buffer object
 179  *
 180  * This structure defines the generic parts for GEM buffer objects, which are
 181  * mostly around handling mmap and userspace handles.
 182  *
 183  * Buffer objects are often abbreviated to BO.
 184  */
 185 struct drm_gem_object {
 186         /**
 187          * @refcount:
 188          *
 189          * Reference count of this object
 190          *
 191          * Please use drm_gem_object_get() to acquire and drm_gem_object_put_locked()
 192          * or drm_gem_object_put() to release a reference to a GEM
 193          * buffer object.
 194          */
 195         struct kref refcount;
 196
 197         /**
 198          * @handle_count:
 199          *
 200          * This is the GEM file_priv handle count of this object.
 201          *
 202          * Each handle also holds a reference. Note that when the handle_count
 203          * drops to 0 any global names (e.g. the id in the flink namespace) will
 204          * be cleared.
 205          *
 206          * Protected by &drm_device.object_name_lock.
 207          */
 208         unsigned handle_count;
 209
 210         /**
 211          * @dev: DRM dev this object belongs to.
 212          */
 213         struct drm_device *dev;
 214
 215         /**
 216          * @filp:
 217          *
 218          * SHMEM file node used as backing storage for swappable buffer objects.
 219          * GEM also supports driver private objects with driver-specific backing
 220          * storage (contiguous CMA memory, special reserved blocks). In this
 221          * case @filp is NULL.
 222          */
 223         struct file *filp;
 224
 225         /**
 226          * @vma_node:
 227          *
 228          * Mapping info for this object to support mmap. Drivers are supposed to
 229          * allocate the mmap offset using drm_gem_create_mmap_offset(). The
 230          * offset itself can be retrieved using drm_vma_node_offset_addr().
 231          *
 232          * Memory mapping itself is handled by drm_gem_mmap(), which also checks
 233          * that userspace is allowed to access the object.
 234          */
 235         struct drm_vma_offset_node vma_node;
 236
 237         /**
 238          * @size:
 239          *
 240          * Size of the object, in bytes.  Immutable over the object's
 241          * lifetime.
 242          */
 243         size_t size;
 244
 245         /**
 246          * @name:
 247          *
 248          * Global name for this object, starts at 1. 0 means unnamed.
 249          * Access is covered by &drm_device.object_name_lock. This is used by
 250          * the GEM_FLINK and GEM_OPEN ioctls.
 251          */
 252         int name;
 253
 254         /**
 255          * @dma_buf:
 256          *
 257          * dma-buf associated with this GEM object.
 258          *
 259          * Pointer to the dma-buf associated with this gem object (either
 260          * through importing or exporting). We break the resulting reference
 261          * loop when the last gem handle for this object is released.
 262          *
 263          * Protected by &drm_device.object_name_lock.
 264          */
 265         struct dma_buf *dma_buf;
 266
 267         /**
 268          * @import_attach:
 269          *
 270          * dma-buf attachment backing this object.
 271          *
 272          * Any foreign dma_buf imported as a gem object has this set to the
 273          * attachment point for the device. This is invariant over the lifetime
 274          * of a gem object.
 275          *
 276          * The &drm_gem_object_funcs.free callback is responsible for
 277          * cleaning up the dma_buf attachment and references acquired at import
 278          * time.
 279          *
 280          * Note that the drm gem/prime core does not depend upon drivers setting
 281          * this field any more. So for drivers where this doesn't make sense
 282          * (e.g. virtual devices or a displaylink behind an usb bus) they can
 283          * simply leave it as NULL.
 284          */
 285         struct dma_buf_attachment *import_attach;
 286
 287         /**
 288          * @resv:
 289          *
 290          * Pointer to reservation object associated with the this GEM object.
 291          *
 292          * Normally (@resv == &@_resv) except for imported GEM objects.
 293          */
 294         struct dma_resv *resv;
 295
 296         /**
 297          * @_resv:
 298          *
 299          * A reservation object for this GEM object.
 300          *
 301          * This is unused for imported GEM objects.
 302          */
 303         struct dma_resv _resv;
 304
 305         /**
 306          * @funcs:
 307          *
 308          * Optional GEM object functions. If this is set, it will be used instead of the
 309          * corresponding &drm_driver GEM callbacks.
 310          *
 311          * New drivers should use this.
 312          *
 313          */
 314         const struct drm_gem_object_funcs *funcs;
 315 };
 316
 317 /**
 318  * DEFINE_DRM_GEM_FOPS() - macro to generate file operations for GEM drivers
 319  * @name: name for the generated structure
 320  *
 321  * This macro autogenerates a suitable &struct file_operations for GEM based
 322  * drivers, which can be assigned to &drm_driver.fops. Note that this structure
 323  * cannot be shared between drivers, because it contains a reference to the
 324  * current module using THIS_MODULE.
 325  *
 326  * Note that the declaration is already marked as static - if you need a
 327  * non-static version of this you're probably doing it wrong and will break the
 328  * THIS_MODULE reference by accident.
 329  */
 330 #define DEFINE_DRM_GEM_FOPS(name) \
 331         static const struct file_operations name = {\
 332                 .owner          = THIS_MODULE,\
 333                 .open           = drm_open,\
 334                 .release        = drm_release,\
 335                 .unlocked_ioctl = drm_ioctl,\
 336                 .compat_ioctl   = drm_compat_ioctl,\
 337                 .poll           = drm_poll,\
 338                 .read           = drm_read,\
 339                 .llseek         = noop_llseek,\
 340                 .mmap           = drm_gem_mmap,\
 341         }
 342
 343 void drm_gem_object_release(struct drm_gem_object *obj);
 344 void drm_gem_object_free(struct kref *kref);
 345 int drm_gem_object_init(struct drm_device *dev,
 346                         struct drm_gem_object *obj, size_t size);
 347 void drm_gem_private_object_init(struct drm_device *dev,
 348                                  struct drm_gem_object *obj, size_t size);
 349 void drm_gem_vm_open(struct vm_area_struct *vma);
 350 void drm_gem_vm_close(struct vm_area_struct *vma);
 351 int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
 352                      struct vm_area_struct *vma);
 353 int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma);
 354
 355 /**
 356  * drm_gem_object_get - acquire a GEM buffer object reference
 357  * @obj: GEM buffer object
 358  *
 359  * This function acquires an additional reference to @obj. It is illegal to
 360  * call this without already holding a reference. No locks required.
 361  */
 362 static inline void drm_gem_object_get(struct drm_gem_object *obj)
 363 {
 364         kref_get(&obj->refcount);
 365 }
 366
 367 __attribute__((nonnull))
 368 static inline void
 369 __drm_gem_object_put(struct drm_gem_object *obj)
 370 {
 371         kref_put(&obj->refcount, drm_gem_object_free);
 372 }
 373
 374 /**
 375  * drm_gem_object_put - drop a GEM buffer object reference
 376  * @obj: GEM buffer object
 377  *
 378  * This releases a reference to @obj.
 379  */
 380 static inline void
 381 drm_gem_object_put(struct drm_gem_object *obj)
 382 {
 383         if (obj)
 384                 __drm_gem_object_put(obj);
 385 }
 386
 387 void drm_gem_object_put_locked(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__ */