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 /**
  38  * struct drm_gem_object - GEM buffer object
  39  *
  40  * This structure defines the generic parts for GEM buffer objects, which are
  41  * mostly around handling mmap and userspace handles.
  42  *
  43  * Buffer objects are often abbreviated to BO.
  44  */
  45 struct drm_gem_object {
  46         /**
  47          * @refcount:
  48          *
  49          * Reference count of this object
  50          *
  51          * Please use drm_gem_object_reference() to acquire and
  52          * drm_gem_object_unreference() or drm_gem_object_unreference_unlocked()
  53          * to release a reference to a GEM buffer object.
  54          */
  55         struct kref refcount;
  56
  57         /**
  58          * @handle_count:
  59          *
  60          * This is the GEM file_priv handle count of this object.
  61          *
  62          * Each handle also holds a reference. Note that when the handle_count
  63          * drops to 0 any global names (e.g. the id in the flink namespace) will
  64          * be cleared.
  65          *
  66          * Protected by dev->object_name_lock.
  67          */
  68         unsigned handle_count;
  69
  70         /**
  71          * @dev: DRM dev this object belongs to.
  72          */
  73         struct drm_device *dev;
  74
  75         /**
  76          * @filp:
  77          *
  78          * SHMEM file node used as backing storage for swappable buffer objects.
  79          * GEM also supports driver private objects with driver-specific backing
  80          * storage (contiguous CMA memory, special reserved blocks). In this
  81          * case @filp is NULL.
  82          */
  83         struct file *filp;
  84
  85         /**
  86          * @vma_node:
  87          *
  88          * Mapping info for this object to support mmap. Drivers are supposed to
  89          * allocate the mmap offset using drm_gem_create_mmap_offset(). The
  90          * offset itself can be retrieved using drm_vma_node_offset_addr().
  91          *
  92          * Memory mapping itself is handled by drm_gem_mmap(), which also checks
  93          * that userspace is allowed to access the object.
  94          */
  95         struct drm_vma_offset_node vma_node;
  96
  97         /**
  98          * @size:
  99          *
 100          * Size of the object, in bytes.  Immutable over the object's
 101          * lifetime.
 102          */
 103         size_t size;
 104
 105         /**
 106          * @name:
 107          *
 108          * Global name for this object, starts at 1. 0 means unnamed.
 109          * Access is covered by dev->object_name_lock. This is used by the GEM_FLINK
 110          * and GEM_OPEN ioctls.
 111          */
 112         int name;
 113
 114         /**
 115          * @read_domains:
 116          *
 117          * Read memory domains. These monitor which caches contain read/write data
 118          * related to the object. When transitioning from one set of domains
 119          * to another, the driver is called to ensure that caches are suitably
 120          * flushed and invalidated.
 121          */
 122         uint32_t read_domains;
 123
 124         /**
 125          * @write_domain: Corresponding unique write memory domain.
 126          */
 127         uint32_t write_domain;
 128
 129         /**
 130          * @pending_read_domains:
 131          *
 132          * While validating an exec operation, the
 133          * new read/write domain values are computed here.
 134          * They will be transferred to the above values
 135          * at the point that any cache flushing occurs
 136          */
 137         uint32_t pending_read_domains;
 138
 139         /**
 140          * @pending_write_domain: Write domain similar to @pending_read_domains.
 141          */
 142         uint32_t pending_write_domain;
 143
 144         /**
 145          * @dma_buf:
 146          *
 147          * dma-buf associated with this GEM object.
 148          *
 149          * Pointer to the dma-buf associated with this gem object (either
 150          * through importing or exporting). We break the resulting reference
 151          * loop when the last gem handle for this object is released.
 152          *
 153          * Protected by obj->object_name_lock.
 154          */
 155         struct dma_buf *dma_buf;
 156
 157         /**
 158          * @import_attach:
 159          *
 160          * dma-buf attachment backing this object.
 161          *
 162          * Any foreign dma_buf imported as a gem object has this set to the
 163          * attachment point for the device. This is invariant over the lifetime
 164          * of a gem object.
 165          *
 166          * The driver's ->gem_free_object callback is responsible for cleaning
 167          * up the dma_buf attachment and references acquired at import time.
 168          *
 169          * Note that the drm gem/prime core does not depend upon drivers setting
 170          * this field any more. So for drivers where this doesn't make sense
 171          * (e.g. virtual devices or a displaylink behind an usb bus) they can
 172          * simply leave it as NULL.
 173          */
 174         struct dma_buf_attachment *import_attach;
 175 };
 176
 177 void drm_gem_object_release(struct drm_gem_object *obj);
 178 void drm_gem_object_free(struct kref *kref);
 179 int drm_gem_object_init(struct drm_device *dev,
 180                         struct drm_gem_object *obj, size_t size);
 181 void drm_gem_private_object_init(struct drm_device *dev,
 182                                  struct drm_gem_object *obj, size_t size);
 183 void drm_gem_vm_open(struct vm_area_struct *vma);
 184 void drm_gem_vm_close(struct vm_area_struct *vma);
 185 int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
 186                      struct vm_area_struct *vma);
 187 int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma);
 188
 189 /**
 190  * drm_gem_object_reference - acquire a GEM BO reference
 191  * @obj: GEM buffer object
 192  *
 193  * This acquires additional reference to @obj. It is illegal to call this
 194  * without already holding a reference. No locks required.
 195  */
 196 static inline void
 197 drm_gem_object_reference(struct drm_gem_object *obj)
 198 {
 199         kref_get(&obj->refcount);
 200 }
 201
 202 /**
 203  * __drm_gem_object_unreference - raw function to release a GEM BO reference
 204  * @obj: GEM buffer object
 205  *
 206  * This function is meant to be used by drivers which are not encumbered with
 207  * dev->struct_mutex legacy locking and which are using the
 208  * gem_free_object_unlocked callback. It avoids all the locking checks and
 209  * locking overhead of drm_gem_object_unreference() and
 210  * drm_gem_object_unreference_unlocked().
 211  *
 212  * Drivers should never call this directly in their code. Instead they should
 213  * wrap it up into a driver_gem_object_unreference(struct driver_gem_object
 214  * *obj) wrapper function, and use that. Shared code should never call this, to
 215  * avoid breaking drivers by accident which still depend upon dev->struct_mutex
 216  * locking.
 217  */
 218 static inline void
 219 __drm_gem_object_unreference(struct drm_gem_object *obj)
 220 {
 221         kref_put(&obj->refcount, drm_gem_object_free);
 222 }
 223
 224 void drm_gem_object_unreference_unlocked(struct drm_gem_object *obj);
 225 void drm_gem_object_unreference(struct drm_gem_object *obj);
 226
 227 int drm_gem_handle_create(struct drm_file *file_priv,
 228                           struct drm_gem_object *obj,
 229                           u32 *handlep);
 230 int drm_gem_handle_delete(struct drm_file *filp, u32 handle);
 231
 232
 233 void drm_gem_free_mmap_offset(struct drm_gem_object *obj);
 234 int drm_gem_create_mmap_offset(struct drm_gem_object *obj);
 235 int drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size);
 236
 237 struct page **drm_gem_get_pages(struct drm_gem_object *obj);
 238 void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
 239                 bool dirty, bool accessed);
 240
 241 struct drm_gem_object *drm_gem_object_lookup(struct drm_file *filp, u32 handle);
 242 int drm_gem_dumb_destroy(struct drm_file *file,
 243                          struct drm_device *dev,
 244                          uint32_t handle);
 245
 246 #endif /* __DRM_GEM_H__ */