1 /************************************************************************** 2 * 3 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA 4 * All Rights Reserved. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, sub license, and/or sell copies of the Software, and to 11 * permit persons to whom the Software is furnished to do so, subject to 12 * the following conditions: 13 * 14 * The above copyright notice and this permission notice (including the 15 * next paragraph) shall be included in all copies or substantial portions 16 * of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, 22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 24 * USE OR OTHER DEALINGS IN THE SOFTWARE. 25 * 26 **************************************************************************/ 27 /* 28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com> 29 */ 30 /** @file ttm_object.h 31 * 32 * Base- and reference object implementation for the various 33 * ttm objects. Implements reference counting, minimal security checks 34 * and release on file close. 35 */ 36 37 #ifndef _TTM_OBJECT_H_ 38 #define _TTM_OBJECT_H_ 39 40 #include <dev/drm2/drm_hashtab.h> 41 #include <dev/drm2/ttm/ttm_memory.h> 42 43 /** 44 * enum ttm_ref_type 45 * 46 * Describes what type of reference a ref object holds. 47 * 48 * TTM_REF_USAGE is a simple refcount on a base object. 49 * 50 * TTM_REF_SYNCCPU_READ is a SYNCCPU_READ reference on a 51 * buffer object. 52 * 53 * TTM_REF_SYNCCPU_WRITE is a SYNCCPU_WRITE reference on a 54 * buffer object. 55 * 56 */ 57 58 enum ttm_ref_type { 59 TTM_REF_USAGE, 60 TTM_REF_SYNCCPU_READ, 61 TTM_REF_SYNCCPU_WRITE, 62 TTM_REF_NUM 63 }; 64 65 /** 66 * enum ttm_object_type 67 * 68 * One entry per ttm object type. 69 * Device-specific types should use the 70 * ttm_driver_typex types. 71 */ 72 73 enum ttm_object_type { 74 ttm_fence_type, 75 ttm_buffer_type, 76 ttm_lock_type, 77 ttm_driver_type0 = 256, 78 ttm_driver_type1, 79 ttm_driver_type2, 80 ttm_driver_type3, 81 ttm_driver_type4, 82 ttm_driver_type5 83 }; 84 85 struct ttm_object_file; 86 struct ttm_object_device; 87 88 /** 89 * struct ttm_base_object 90 * 91 * @hash: hash entry for the per-device object hash. 92 * @type: derived type this object is base class for. 93 * @shareable: Other ttm_object_files can access this object. 94 * 95 * @tfile: Pointer to ttm_object_file of the creator. 96 * NULL if the object was not created by a user request. 97 * (kernel object). 98 * 99 * @refcount: Number of references to this object, not 100 * including the hash entry. A reference to a base object can 101 * only be held by a ref object. 102 * 103 * @refcount_release: A function to be called when there are 104 * no more references to this object. This function should 105 * destroy the object (or make sure destruction eventually happens), 106 * and when it is called, the object has 107 * already been taken out of the per-device hash. The parameter 108 * "base" should be set to NULL by the function. 109 * 110 * @ref_obj_release: A function to be called when a reference object 111 * with another ttm_ref_type than TTM_REF_USAGE is deleted. 112 * This function may, for example, release a lock held by a user-space 113 * process. 114 * 115 * This struct is intended to be used as a base struct for objects that 116 * are visible to user-space. It provides a global name, race-safe 117 * access and refcounting, minimal access contol and hooks for unref actions. 118 */ 119 120 struct ttm_base_object { 121 /* struct rcu_head rhead;XXXKIB */ 122 struct drm_hash_item hash; 123 enum ttm_object_type object_type; 124 bool shareable; 125 struct ttm_object_file *tfile; 126 u_int refcount; 127 void (*refcount_release) (struct ttm_base_object **base); 128 void (*ref_obj_release) (struct ttm_base_object *base, 129 enum ttm_ref_type ref_type); 130 }; 131 132 /** 133 * ttm_base_object_init 134 * 135 * @tfile: Pointer to a struct ttm_object_file. 136 * @base: The struct ttm_base_object to initialize. 137 * @shareable: This object is shareable with other applcations. 138 * (different @tfile pointers.) 139 * @type: The object type. 140 * @refcount_release: See the struct ttm_base_object description. 141 * @ref_obj_release: See the struct ttm_base_object description. 142 * 143 * Initializes a struct ttm_base_object. 144 */ 145 146 extern int ttm_base_object_init(struct ttm_object_file *tfile, 147 struct ttm_base_object *base, 148 bool shareable, 149 enum ttm_object_type type, 150 void (*refcount_release) (struct ttm_base_object 151 **), 152 void (*ref_obj_release) (struct ttm_base_object 153 *, 154 enum ttm_ref_type 155 ref_type)); 156 157 /** 158 * ttm_base_object_lookup 159 * 160 * @tfile: Pointer to a struct ttm_object_file. 161 * @key: Hash key 162 * 163 * Looks up a struct ttm_base_object with the key @key. 164 * Also verifies that the object is visible to the application, by 165 * comparing the @tfile argument and checking the object shareable flag. 166 */ 167 168 extern struct ttm_base_object *ttm_base_object_lookup(struct ttm_object_file 169 *tfile, uint32_t key); 170 171 /** 172 * ttm_base_object_unref 173 * 174 * @p_base: Pointer to a pointer referencing a struct ttm_base_object. 175 * 176 * Decrements the base object refcount and clears the pointer pointed to by 177 * p_base. 178 */ 179 180 extern void ttm_base_object_unref(struct ttm_base_object **p_base); 181 182 /** 183 * ttm_ref_object_add. 184 * 185 * @tfile: A struct ttm_object_file representing the application owning the 186 * ref_object. 187 * @base: The base object to reference. 188 * @ref_type: The type of reference. 189 * @existed: Upon completion, indicates that an identical reference object 190 * already existed, and the refcount was upped on that object instead. 191 * 192 * Adding a ref object to a base object is basically like referencing the 193 * base object, but a user-space application holds the reference. When the 194 * file corresponding to @tfile is closed, all its reference objects are 195 * deleted. A reference object can have different types depending on what 196 * it's intended for. It can be refcounting to prevent object destruction, 197 * When user-space takes a lock, it can add a ref object to that lock to 198 * make sure the lock is released if the application dies. A ref object 199 * will hold a single reference on a base object. 200 */ 201 extern int ttm_ref_object_add(struct ttm_object_file *tfile, 202 struct ttm_base_object *base, 203 enum ttm_ref_type ref_type, bool *existed); 204 /** 205 * ttm_ref_object_base_unref 206 * 207 * @key: Key representing the base object. 208 * @ref_type: Ref type of the ref object to be dereferenced. 209 * 210 * Unreference a ref object with type @ref_type 211 * on the base object identified by @key. If there are no duplicate 212 * references, the ref object will be destroyed and the base object 213 * will be unreferenced. 214 */ 215 extern int ttm_ref_object_base_unref(struct ttm_object_file *tfile, 216 unsigned long key, 217 enum ttm_ref_type ref_type); 218 219 /** 220 * ttm_object_file_init - initialize a struct ttm_object file 221 * 222 * @tdev: A struct ttm_object device this file is initialized on. 223 * @hash_order: Order of the hash table used to hold the reference objects. 224 * 225 * This is typically called by the file_ops::open function. 226 */ 227 228 extern struct ttm_object_file *ttm_object_file_init(struct ttm_object_device 229 *tdev, 230 unsigned int hash_order); 231 232 /** 233 * ttm_object_file_release - release data held by a ttm_object_file 234 * 235 * @p_tfile: Pointer to pointer to the ttm_object_file object to release. 236 * *p_tfile will be set to NULL by this function. 237 * 238 * Releases all data associated by a ttm_object_file. 239 * Typically called from file_ops::release. The caller must 240 * ensure that there are no concurrent users of tfile. 241 */ 242 243 extern void ttm_object_file_release(struct ttm_object_file **p_tfile); 244 245 /** 246 * ttm_object device init - initialize a struct ttm_object_device 247 * 248 * @hash_order: Order of hash table used to hash the base objects. 249 * 250 * This function is typically called on device initialization to prepare 251 * data structures needed for ttm base and ref objects. 252 */ 253 254 extern struct ttm_object_device *ttm_object_device_init 255 (struct ttm_mem_global *mem_glob, unsigned int hash_order); 256 257 /** 258 * ttm_object_device_release - release data held by a ttm_object_device 259 * 260 * @p_tdev: Pointer to pointer to the ttm_object_device object to release. 261 * *p_tdev will be set to NULL by this function. 262 * 263 * Releases all data associated by a ttm_object_device. 264 * Typically called from driver::unload before the destruction of the 265 * device private data structure. 266 */ 267 268 extern void ttm_object_device_release(struct ttm_object_device **p_tdev); 269 270 #endif 271