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          * @pending_read_domains:
 135          *
 136          * While validating an exec operation, the
 137          * new read/write domain values are computed here.
 138          * They will be transferred to the above values
 139          * at the point that any cache flushing occurs
 140          */
 141         uint32_t pending_read_domains;
 142
 143         /**
 144          * @pending_write_domain: Write domain similar to @pending_read_domains.
 145          */
 146         uint32_t pending_write_domain;
 147
 148         /**
 149          * @dma_buf:
 150          *
 151          * dma-buf associated with this GEM object.
 152          *
 153          * Pointer to the dma-buf associated with this gem object (either
 154          * through importing or exporting). We break the resulting reference
 155          * loop when the last gem handle for this object is released.
 156          *
 157          * Protected by &drm_device.object_name_lock.
 158          */
 159         struct dma_buf *dma_buf;
 160
 161         /**
 162          * @import_attach:
 163          *
 164          * dma-buf attachment backing this object.
 165          *
 166          * Any foreign dma_buf imported as a gem object has this set to the
 167          * attachment point for the device. This is invariant over the lifetime
 168          * of a gem object.
 169          *
 170          * The &drm_driver.gem_free_object callback is responsible for cleaning
 171          * up the dma_buf attachment and references acquired at import time.
 172          *
 173          * Note that the drm gem/prime core does not depend upon drivers setting
 174          * this field any more. So for drivers where this doesn't make sense
 175          * (e.g. virtual devices or a displaylink behind an usb bus) they can
 176          * simply leave it as NULL.
 177          */
 178         struct dma_buf_attachment *import_attach;
 179 };
 180
 181 /**
 182  * DEFINE_DRM_GEM_FOPS() - macro to generate file operations for GEM drivers
 183  * @name: name for the generated structure
 184  *
 185  * This macro autogenerates a suitable &struct file_operations for GEM based
 186  * drivers, which can be assigned to &drm_driver.fops. Note that this structure
 187  * cannot be shared between drivers, because it contains a reference to the
 188  * current module using THIS_MODULE.
 189  *
 190  * Note that the declaration is already marked as static - if you need a
 191  * non-static version of this you're probably doing it wrong and will break the
 192  * THIS_MODULE reference by accident.
 193  */
 194 #define DEFINE_DRM_GEM_FOPS(name) \
 195         static const struct file_operations name = {\
 196                 .owner          = THIS_MODULE,\
 197                 .open           = drm_open,\
 198                 .release        = drm_release,\
 199                 .unlocked_ioctl = drm_ioctl,\
 200                 .compat_ioctl   = drm_compat_ioctl,\
 201                 .poll           = drm_poll,\
 202                 .read           = drm_read,\
 203                 .llseek         = noop_llseek,\
 204                 .mmap           = drm_gem_mmap,\
 205         }
 206
 207 void drm_gem_object_release(struct drm_gem_object *obj);
 208 void drm_gem_object_free(struct kref *kref);
 209 int drm_gem_object_init(struct drm_device *dev,
 210                         struct drm_gem_object *obj, size_t size);
 211 void drm_gem_private_object_init(struct drm_device *dev,
 212                                  struct drm_gem_object *obj, size_t size);
 213 void drm_gem_vm_open(struct vm_area_struct *vma);
 214 void drm_gem_vm_close(struct vm_area_struct *vma);
 215 int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
 216                      struct vm_area_struct *vma);
 217 int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma);
 218
 219 /**
 220  * drm_gem_object_get - acquire a GEM buffer object reference
 221  * @obj: GEM buffer object
 222  *
 223  * This function acquires an additional reference to @obj. It is illegal to
 224  * call this without already holding a reference. No locks required.
 225  */
 226 static inline void drm_gem_object_get(struct drm_gem_object *obj)
 227 {
 228         kref_get(&obj->refcount);
 229 }
 230
 231 /**
 232  * __drm_gem_object_put - raw function to release a GEM buffer object reference
 233  * @obj: GEM buffer object
 234  *
 235  * This function is meant to be used by drivers which are not encumbered with
 236  * &drm_device.struct_mutex legacy locking and which are using the
 237  * gem_free_object_unlocked callback. It avoids all the locking checks and
 238  * locking overhead of drm_gem_object_put() and drm_gem_object_put_unlocked().
 239  *
 240  * Drivers should never call this directly in their code. Instead they should
 241  * wrap it up into a ``driver_gem_object_put(struct driver_gem_object *obj)``
 242  * wrapper function, and use that. Shared code should never call this, to
 243  * avoid breaking drivers by accident which still depend upon
 244  * &drm_device.struct_mutex locking.
 245  */
 246 static inline void
 247 __drm_gem_object_put(struct drm_gem_object *obj)
 248 {
 249         kref_put(&obj->refcount, drm_gem_object_free);
 250 }
 251
 252 void drm_gem_object_put_unlocked(struct drm_gem_object *obj);
 253 void drm_gem_object_put(struct drm_gem_object *obj);
 254
 255 /**
 256  * drm_gem_object_reference - acquire a GEM buffer object reference
 257  * @obj: GEM buffer object
 258  *
 259  * This is a compatibility alias for drm_gem_object_get() and should not be
 260  * used by new code.
 261  */
 262 static inline void drm_gem_object_reference(struct drm_gem_object *obj)
 263 {
 264         drm_gem_object_get(obj);
 265 }
 266
 267 /**
 268  * __drm_gem_object_unreference - raw function to release a GEM buffer object
 269  *                                reference
 270  * @obj: GEM buffer object
 271  *
 272  * This is a compatibility alias for __drm_gem_object_put() and should not be
 273  * used by new code.
 274  */
 275 static inline void __drm_gem_object_unreference(struct drm_gem_object *obj)
 276 {
 277         __drm_gem_object_put(obj);
 278 }
 279
 280 /**
 281  * drm_gem_object_unreference_unlocked - release a GEM buffer object reference
 282  * @obj: GEM buffer object
 283  *
 284  * This is a compatibility alias for drm_gem_object_put_unlocked() and should
 285  * not be used by new code.
 286  */
 287 static inline void
 288 drm_gem_object_unreference_unlocked(struct drm_gem_object *obj)
 289 {
 290         drm_gem_object_put_unlocked(obj);
 291 }
 292
 293 /**
 294  * drm_gem_object_unreference - release a GEM buffer object reference
 295  * @obj: GEM buffer object
 296  *
 297  * This is a compatibility alias for drm_gem_object_put() and should not be
 298  * used by new code.
 299  */
 300 static inline void drm_gem_object_unreference(struct drm_gem_object *obj)
 301 {
 302         drm_gem_object_put(obj);
 303 }
 304
 305 int drm_gem_handle_create(struct drm_file *file_priv,
 306                           struct drm_gem_object *obj,
 307                           u32 *handlep);
 308 int drm_gem_handle_delete(struct drm_file *filp, u32 handle);
 309
 310
 311 void drm_gem_free_mmap_offset(struct drm_gem_object *obj);
 312 int drm_gem_create_mmap_offset(struct drm_gem_object *obj);
 313 int drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size);
 314
 315 struct page **drm_gem_get_pages(struct drm_gem_object *obj);
 316 void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
 317                 bool dirty, bool accessed);
 318
 319 struct drm_gem_object *drm_gem_object_lookup(struct drm_file *filp, u32 handle);
 320 int drm_gem_dumb_destroy(struct drm_file *file,
 321                          struct drm_device *dev,
 322                          uint32_t handle);
 323
 324 #endif /* __DRM_GEM_H__ */