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 /**
  42  * struct drm_gem_object - GEM buffer object
  43  *
  44  * This structure defines the generic parts for GEM buffer objects, which are
  45  * mostly around handling mmap and userspace handles.
  46  *
  47  * Buffer objects are often abbreviated to BO.
  48  */
  49 struct drm_gem_object {
  50         /**
  51          * @refcount:
  52          *
  53          * Reference count of this object
  54          *
  55          * Please use drm_gem_object_get() to acquire and drm_gem_object_put()
  56          * or drm_gem_object_put_unlocked() to release a reference to a GEM
  57          * buffer object.
  58          */
  59         struct kref refcount;
  60
  61         /**
  62          * @handle_count:
  63          *
  64          * This is the GEM file_priv handle count of this object.
  65          *
  66          * Each handle also holds a reference. Note that when the handle_count
  67          * drops to 0 any global names (e.g. the id in the flink namespace) will
  68          * be cleared.
  69          *
  70          * Protected by &drm_device.object_name_lock.
  71          */
  72         unsigned handle_count;
  73
  74         /**
  75          * @dev: DRM dev this object belongs to.
  76          */
  77         struct drm_device *dev;
  78
  79         /**
  80          * @filp:
  81          *
  82          * SHMEM file node used as backing storage for swappable buffer objects.
  83          * GEM also supports driver private objects with driver-specific backing
  84          * storage (contiguous CMA memory, special reserved blocks). In this
  85          * case @filp is NULL.
  86          */
  87         struct file *filp;
  88
  89         /**
  90          * @vma_node:
  91          *
  92          * Mapping info for this object to support mmap. Drivers are supposed to
  93          * allocate the mmap offset using drm_gem_create_mmap_offset(). The
  94          * offset itself can be retrieved using drm_vma_node_offset_addr().
  95          *
  96          * Memory mapping itself is handled by drm_gem_mmap(), which also checks
  97          * that userspace is allowed to access the object.
  98          */
  99         struct drm_vma_offset_node vma_node;
 100
 101         /**
 102          * @size:
 103          *
 104          * Size of the object, in bytes.  Immutable over the object's
 105          * lifetime.
 106          */
 107         size_t size;
 108
 109         /**
 110          * @name:
 111          *
 112          * Global name for this object, starts at 1. 0 means unnamed.
 113          * Access is covered by &drm_device.object_name_lock. This is used by
 114          * the GEM_FLINK and GEM_OPEN ioctls.
 115          */
 116         int name;
 117
 118         /**
 119          * @read_domains:
 120          *
 121          * Read memory domains. These monitor which caches contain read/write data
 122          * related to the object. When transitioning from one set of domains
 123          * to another, the driver is called to ensure that caches are suitably
 124          * flushed and invalidated.
 125          */
 126         uint32_t read_domains;
 127
 128         /**
 129          * @write_domain: Corresponding unique write memory domain.
 130          */
 131         uint32_t write_domain;
 132
 133         /**
 134          * @dma_buf:
 135          *
 136          * dma-buf associated with this GEM object.
 137          *
 138          * Pointer to the dma-buf associated with this gem object (either
 139          * through importing or exporting). We break the resulting reference
 140          * loop when the last gem handle for this object is released.
 141          *
 142          * Protected by &drm_device.object_name_lock.
 143          */
 144         struct dma_buf *dma_buf;
 145
 146         /**
 147          * @import_attach:
 148          *
 149          * dma-buf attachment backing this object.
 150          *
 151          * Any foreign dma_buf imported as a gem object has this set to the
 152          * attachment point for the device. This is invariant over the lifetime
 153          * of a gem object.
 154          *
 155          * The &drm_driver.gem_free_object callback is responsible for cleaning
 156          * up the dma_buf attachment and references acquired at import time.
 157          *
 158          * Note that the drm gem/prime core does not depend upon drivers setting
 159          * this field any more. So for drivers where this doesn't make sense
 160          * (e.g. virtual devices or a displaylink behind an usb bus) they can
 161          * simply leave it as NULL.
 162          */
 163         struct dma_buf_attachment *import_attach;
 164 };
 165
 166 /**
 167  * DEFINE_DRM_GEM_FOPS() - macro to generate file operations for GEM drivers
 168  * @name: name for the generated structure
 169  *
 170  * This macro autogenerates a suitable &struct file_operations for GEM based
 171  * drivers, which can be assigned to &drm_driver.fops. Note that this structure
 172  * cannot be shared between drivers, because it contains a reference to the
 173  * current module using THIS_MODULE.
 174  *
 175  * Note that the declaration is already marked as static - if you need a
 176  * non-static version of this you're probably doing it wrong and will break the
 177  * THIS_MODULE reference by accident.
 178  */
 179 #define DEFINE_DRM_GEM_FOPS(name) \
 180         static const struct file_operations name = {\
 181                 .owner          = THIS_MODULE,\
 182                 .open           = drm_open,\
 183                 .release        = drm_release,\
 184                 .unlocked_ioctl = drm_ioctl,\
 185                 .compat_ioctl   = drm_compat_ioctl,\
 186                 .poll           = drm_poll,\
 187                 .read           = drm_read,\
 188                 .llseek         = noop_llseek,\
 189                 .mmap           = drm_gem_mmap,\
 190         }
 191
 192 void drm_gem_object_release(struct drm_gem_object *obj);
 193 void drm_gem_object_free(struct kref *kref);
 194 int drm_gem_object_init(struct drm_device *dev,
 195                         struct drm_gem_object *obj, size_t size);
 196 void drm_gem_private_object_init(struct drm_device *dev,
 197                                  struct drm_gem_object *obj, size_t size);
 198 void drm_gem_vm_open(struct vm_area_struct *vma);
 199 void drm_gem_vm_close(struct vm_area_struct *vma);
 200 int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
 201                      struct vm_area_struct *vma);
 202 int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma);
 203
 204 /**
 205  * drm_gem_object_get - acquire a GEM buffer object reference
 206  * @obj: GEM buffer object
 207  *
 208  * This function acquires an additional reference to @obj. It is illegal to
 209  * call this without already holding a reference. No locks required.
 210  */
 211 static inline void drm_gem_object_get(struct drm_gem_object *obj)
 212 {
 213         kref_get(&obj->refcount);
 214 }
 215
 216 /**
 217  * __drm_gem_object_put - raw function to release a GEM buffer object reference
 218  * @obj: GEM buffer object
 219  *
 220  * This function is meant to be used by drivers which are not encumbered with
 221  * &drm_device.struct_mutex legacy locking and which are using the
 222  * gem_free_object_unlocked callback. It avoids all the locking checks and
 223  * locking overhead of drm_gem_object_put() and drm_gem_object_put_unlocked().
 224  *
 225  * Drivers should never call this directly in their code. Instead they should
 226  * wrap it up into a ``driver_gem_object_put(struct driver_gem_object *obj)``
 227  * wrapper function, and use that. Shared code should never call this, to
 228  * avoid breaking drivers by accident which still depend upon
 229  * &drm_device.struct_mutex locking.
 230  */
 231 static inline void
 232 __drm_gem_object_put(struct drm_gem_object *obj)
 233 {
 234         kref_put(&obj->refcount, drm_gem_object_free);
 235 }
 236
 237 void drm_gem_object_put_unlocked(struct drm_gem_object *obj);
 238 void drm_gem_object_put(struct drm_gem_object *obj);
 239
 240 /**
 241  * drm_gem_object_reference - acquire a GEM buffer object reference
 242  * @obj: GEM buffer object
 243  *
 244  * This is a compatibility alias for drm_gem_object_get() and should not be
 245  * used by new code.
 246  */
 247 static inline void drm_gem_object_reference(struct drm_gem_object *obj)
 248 {
 249         drm_gem_object_get(obj);
 250 }
 251
 252 /**
 253  * __drm_gem_object_unreference - raw function to release a GEM buffer object
 254  *                                reference
 255  * @obj: GEM buffer object
 256  *
 257  * This is a compatibility alias for __drm_gem_object_put() and should not be
 258  * used by new code.
 259  */
 260 static inline void __drm_gem_object_unreference(struct drm_gem_object *obj)
 261 {
 262         __drm_gem_object_put(obj);
 263 }
 264
 265 /**
 266  * drm_gem_object_unreference_unlocked - release a GEM buffer object reference
 267  * @obj: GEM buffer object
 268  *
 269  * This is a compatibility alias for drm_gem_object_put_unlocked() and should
 270  * not be used by new code.
 271  */
 272 static inline void
 273 drm_gem_object_unreference_unlocked(struct drm_gem_object *obj)
 274 {
 275         drm_gem_object_put_unlocked(obj);
 276 }
 277
 278 /**
 279  * drm_gem_object_unreference - release a GEM buffer object reference
 280  * @obj: GEM buffer object
 281  *
 282  * This is a compatibility alias for drm_gem_object_put() and should not be
 283  * used by new code.
 284  */
 285 static inline void drm_gem_object_unreference(struct drm_gem_object *obj)
 286 {
 287         drm_gem_object_put(obj);
 288 }
 289
 290 int drm_gem_handle_create(struct drm_file *file_priv,
 291                           struct drm_gem_object *obj,
 292                           u32 *handlep);
 293 int drm_gem_handle_delete(struct drm_file *filp, u32 handle);
 294
 295
 296 void drm_gem_free_mmap_offset(struct drm_gem_object *obj);
 297 int drm_gem_create_mmap_offset(struct drm_gem_object *obj);
 298 int drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size);
 299
 300 struct page **drm_gem_get_pages(struct drm_gem_object *obj);
 301 void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
 302                 bool dirty, bool accessed);
 303
 304 struct drm_gem_object *drm_gem_object_lookup(struct drm_file *filp, u32 handle);
 305 int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
 306                             u32 handle, u64 *offset);
 307 int drm_gem_dumb_destroy(struct drm_file *file,
 308                          struct drm_device *dev,
 309                          uint32_t handle);
 310
 311 #endif /* __DRM_GEM_H__ */