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
  39 #include <drm/drm_vma_manager.h>
  40
  41 struct drm_gem_object;
  42
  43 /**
  44  * struct drm_gem_object_funcs - GEM object functions
  45  */
  46 struct drm_gem_object_funcs {
  47         /**
  48          * @free:
  49          *
  50          * Deconstructor for drm_gem_objects.
  51          *
  52          * This callback is mandatory.
  53          */
  54         void (*free)(struct drm_gem_object *obj);
  55
  56         /**
  57          * @open:
  58          *
  59          * Called upon GEM handle creation.
  60          *
  61          * This callback is optional.
  62          */
  63         int (*open)(struct drm_gem_object *obj, struct drm_file *file);
  64
  65         /**
  66          * @close:
  67          *
  68          * Called upon GEM handle release.
  69          *
  70          * This callback is optional.
  71          */
  72         void (*close)(struct drm_gem_object *obj, struct drm_file *file);
  73
  74         /**
  75          * @print_info:
  76          *
  77          * If driver subclasses struct &drm_gem_object, it can implement this
  78          * optional hook for printing additional driver specific info.
  79          *
  80          * drm_printf_indent() should be used in the callback passing it the
  81          * indent argument.
  82          *
  83          * This callback is called from drm_gem_print_info().
  84          *
  85          * This callback is optional.
  86          */
  87         void (*print_info)(struct drm_printer *p, unsigned int indent,
  88                            const struct drm_gem_object *obj);
  89
  90         /**
  91          * @export:
  92          *
  93          * Export backing buffer as a &dma_buf.
  94          * If this is not set drm_gem_prime_export() is used.
  95          *
  96          * This callback is optional.
  97          */
  98         struct dma_buf *(*export)(struct drm_gem_object *obj, int flags);
  99
 100         /**
 101          * @pin:
 102          *
 103          * Pin backing buffer in memory.
 104          *
 105          * This callback is optional.
 106          */
 107         int (*pin)(struct drm_gem_object *obj);
 108
 109         /**
 110          * @unpin:
 111          *
 112          * Unpin backing buffer.
 113          *
 114          * This callback is optional.
 115          */
 116         void (*unpin)(struct drm_gem_object *obj);
 117
 118         /**
 119          * @get_sg_table:
 120          *
 121          * Returns a Scatter-Gather table representation of the buffer.
 122          * Used when exporting a buffer.
 123          *
 124          * This callback is mandatory if buffer export is supported.
 125          */
 126         struct sg_table *(*get_sg_table)(struct drm_gem_object *obj);
 127
 128         /**
 129          * @vmap:
 130          *
 131          * Returns a virtual address for the buffer.
 132          *
 133          * This callback is optional.
 134          */
 135         void *(*vmap)(struct drm_gem_object *obj);
 136
 137         /**
 138          * @vunmap:
 139          *
 140          * Releases the the address previously returned by @vmap.
 141          *
 142          * This callback is optional.
 143          */
 144         void (*vunmap)(struct drm_gem_object *obj, void *vaddr);
 145
 146         /**
 147          * @vm_ops:
 148          *
 149          * Virtual memory operations used with mmap.
 150          *
 151          * This is optional but necessary for mmap support.
 152          */
 153         const struct vm_operations_struct *vm_ops;
 154 };
 155
 156 /**
 157  * struct drm_gem_object - GEM buffer object
 158  *
 159  * This structure defines the generic parts for GEM buffer objects, which are
 160  * mostly around handling mmap and userspace handles.
 161  *
 162  * Buffer objects are often abbreviated to BO.
 163  */
 164 struct drm_gem_object {
 165         /**
 166          * @refcount:
 167          *
 168          * Reference count of this object
 169          *
 170          * Please use drm_gem_object_get() to acquire and drm_gem_object_put()
 171          * or drm_gem_object_put_unlocked() to release a reference to a GEM
 172          * buffer object.
 173          */
 174         struct kref refcount;
 175
 176         /**
 177          * @handle_count:
 178          *
 179          * This is the GEM file_priv handle count of this object.
 180          *
 181          * Each handle also holds a reference. Note that when the handle_count
 182          * drops to 0 any global names (e.g. the id in the flink namespace) will
 183          * be cleared.
 184          *
 185          * Protected by &drm_device.object_name_lock.
 186          */
 187         unsigned handle_count;
 188
 189         /**
 190          * @dev: DRM dev this object belongs to.
 191          */
 192         struct drm_device *dev;
 193
 194         /**
 195          * @filp:
 196          *
 197          * SHMEM file node used as backing storage for swappable buffer objects.
 198          * GEM also supports driver private objects with driver-specific backing
 199          * storage (contiguous CMA memory, special reserved blocks). In this
 200          * case @filp is NULL.
 201          */
 202         struct file *filp;
 203
 204         /**
 205          * @vma_node:
 206          *
 207          * Mapping info for this object to support mmap. Drivers are supposed to
 208          * allocate the mmap offset using drm_gem_create_mmap_offset(). The
 209          * offset itself can be retrieved using drm_vma_node_offset_addr().
 210          *
 211          * Memory mapping itself is handled by drm_gem_mmap(), which also checks
 212          * that userspace is allowed to access the object.
 213          */
 214         struct drm_vma_offset_node vma_node;
 215
 216         /**
 217          * @size:
 218          *
 219          * Size of the object, in bytes.  Immutable over the object's
 220          * lifetime.
 221          */
 222         size_t size;
 223
 224         /**
 225          * @name:
 226          *
 227          * Global name for this object, starts at 1. 0 means unnamed.
 228          * Access is covered by &drm_device.object_name_lock. This is used by
 229          * the GEM_FLINK and GEM_OPEN ioctls.
 230          */
 231         int name;
 232
 233         /**
 234          * @dma_buf:
 235          *
 236          * dma-buf associated with this GEM object.
 237          *
 238          * Pointer to the dma-buf associated with this gem object (either
 239          * through importing or exporting). We break the resulting reference
 240          * loop when the last gem handle for this object is released.
 241          *
 242          * Protected by &drm_device.object_name_lock.
 243          */
 244         struct dma_buf *dma_buf;
 245
 246         /**
 247          * @import_attach:
 248          *
 249          * dma-buf attachment backing this object.
 250          *
 251          * Any foreign dma_buf imported as a gem object has this set to the
 252          * attachment point for the device. This is invariant over the lifetime
 253          * of a gem object.
 254          *
 255          * The &drm_driver.gem_free_object callback is responsible for cleaning
 256          * up the dma_buf attachment and references acquired at import time.
 257          *
 258          * Note that the drm gem/prime core does not depend upon drivers setting
 259          * this field any more. So for drivers where this doesn't make sense
 260          * (e.g. virtual devices or a displaylink behind an usb bus) they can
 261          * simply leave it as NULL.
 262          */
 263         struct dma_buf_attachment *import_attach;
 264
 265         /**
 266          * @funcs:
 267          *
 268          * Optional GEM object functions. If this is set, it will be used instead of the
 269          * corresponding &drm_driver GEM callbacks.
 270          *
 271          * New drivers should use this.
 272          *
 273          */
 274         const struct drm_gem_object_funcs *funcs;
 275 };
 276
 277 /**
 278  * DEFINE_DRM_GEM_FOPS() - macro to generate file operations for GEM drivers
 279  * @name: name for the generated structure
 280  *
 281  * This macro autogenerates a suitable &struct file_operations for GEM based
 282  * drivers, which can be assigned to &drm_driver.fops. Note that this structure
 283  * cannot be shared between drivers, because it contains a reference to the
 284  * current module using THIS_MODULE.
 285  *
 286  * Note that the declaration is already marked as static - if you need a
 287  * non-static version of this you're probably doing it wrong and will break the
 288  * THIS_MODULE reference by accident.
 289  */
 290 #define DEFINE_DRM_GEM_FOPS(name) \
 291         static const struct file_operations name = {\
 292                 .owner          = THIS_MODULE,\
 293                 .open           = drm_open,\
 294                 .release        = drm_release,\
 295                 .unlocked_ioctl = drm_ioctl,\
 296                 .compat_ioctl   = drm_compat_ioctl,\
 297                 .poll           = drm_poll,\
 298                 .read           = drm_read,\
 299                 .llseek         = noop_llseek,\
 300                 .mmap           = drm_gem_mmap,\
 301         }
 302
 303 void drm_gem_object_release(struct drm_gem_object *obj);
 304 void drm_gem_object_free(struct kref *kref);
 305 int drm_gem_object_init(struct drm_device *dev,
 306                         struct drm_gem_object *obj, size_t size);
 307 void drm_gem_private_object_init(struct drm_device *dev,
 308                                  struct drm_gem_object *obj, size_t size);
 309 void drm_gem_vm_open(struct vm_area_struct *vma);
 310 void drm_gem_vm_close(struct vm_area_struct *vma);
 311 int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
 312                      struct vm_area_struct *vma);
 313 int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma);
 314
 315 /**
 316  * drm_gem_object_get - acquire a GEM buffer object reference
 317  * @obj: GEM buffer object
 318  *
 319  * This function acquires an additional reference to @obj. It is illegal to
 320  * call this without already holding a reference. No locks required.
 321  */
 322 static inline void drm_gem_object_get(struct drm_gem_object *obj)
 323 {
 324         kref_get(&obj->refcount);
 325 }
 326
 327 /**
 328  * __drm_gem_object_put - raw function to release a GEM buffer object reference
 329  * @obj: GEM buffer object
 330  *
 331  * This function is meant to be used by drivers which are not encumbered with
 332  * &drm_device.struct_mutex legacy locking and which are using the
 333  * gem_free_object_unlocked callback. It avoids all the locking checks and
 334  * locking overhead of drm_gem_object_put() and drm_gem_object_put_unlocked().
 335  *
 336  * Drivers should never call this directly in their code. Instead they should
 337  * wrap it up into a ``driver_gem_object_put(struct driver_gem_object *obj)``
 338  * wrapper function, and use that. Shared code should never call this, to
 339  * avoid breaking drivers by accident which still depend upon
 340  * &drm_device.struct_mutex locking.
 341  */
 342 static inline void
 343 __drm_gem_object_put(struct drm_gem_object *obj)
 344 {
 345         kref_put(&obj->refcount, drm_gem_object_free);
 346 }
 347
 348 void drm_gem_object_put_unlocked(struct drm_gem_object *obj);
 349 void drm_gem_object_put(struct drm_gem_object *obj);
 350
 351 int drm_gem_handle_create(struct drm_file *file_priv,
 352                           struct drm_gem_object *obj,
 353                           u32 *handlep);
 354 int drm_gem_handle_delete(struct drm_file *filp, u32 handle);
 355
 356
 357 void drm_gem_free_mmap_offset(struct drm_gem_object *obj);
 358 int drm_gem_create_mmap_offset(struct drm_gem_object *obj);
 359 int drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size);
 360
 361 struct page **drm_gem_get_pages(struct drm_gem_object *obj);
 362 void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
 363                 bool dirty, bool accessed);
 364
 365 struct drm_gem_object *drm_gem_object_lookup(struct drm_file *filp, u32 handle);
 366 int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
 367                             u32 handle, u64 *offset);
 368 int drm_gem_dumb_destroy(struct drm_file *file,
 369                          struct drm_device *dev,
 370                          uint32_t handle);
 371
 372 int drm_gem_pin(struct drm_gem_object *obj);
 373 void drm_gem_unpin(struct drm_gem_object *obj);
 374 void *drm_gem_vmap(struct drm_gem_object *obj);
 375 void drm_gem_vunmap(struct drm_gem_object *obj, void *vaddr);
 376
 377 #endif /* __DRM_GEM_H__ */