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1/**************************************************************************2 *3 * Copyright (c) 2006-2023 VMware, Inc., Palo Alto, CA., USA4 * All Rights Reserved.5 *6 * Permission is hereby granted, free of charge, to any person obtaining a7 * copy of this software and associated documentation files (the8 * "Software"), to deal in the Software without restriction, including9 * without limitation the rights to use, copy, modify, merge, publish,10 * distribute, sub license, and/or sell copies of the Software, and to11 * permit persons to whom the Software is furnished to do so, subject to12 * the following conditions:13 *14 * The above copyright notice and this permission notice (including the15 * next paragraph) shall be included in all copies or substantial portions16 * of the Software.17 *18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL21 * 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 OR23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE24 * USE OR OTHER DEALINGS IN THE SOFTWARE.25 *26 **************************************************************************/27/*28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>29 */30/** @file ttm_object.h31 *32 * Base- and reference object implementation for the various33 * ttm objects. Implements reference counting, minimal security checks34 * and release on file close.35 */36 37#ifndef _TTM_OBJECT_H_38#define _TTM_OBJECT_H_39 40#include <linux/dma-buf.h>41#include <linux/kref.h>42#include <linux/list.h>43#include <linux/rcupdate.h>44 45#include <drm/ttm/ttm_bo.h>46 47/**48 * enum ttm_object_type49 *50 * One entry per ttm object type.51 * Device-specific types should use the52 * ttm_driver_typex types.53 */54 55enum ttm_object_type {56 ttm_fence_type,57 ttm_lock_type,58 ttm_prime_type,59 ttm_driver_type0 = 256,60 ttm_driver_type1,61 ttm_driver_type2,62 ttm_driver_type3,63 ttm_driver_type4,64 ttm_driver_type565};66 67struct ttm_object_file;68struct ttm_object_device;69 70/**71 * struct ttm_base_object72 *73 * @hash: hash entry for the per-device object hash.74 * @type: derived type this object is base class for.75 * @shareable: Other ttm_object_files can access this object.76 *77 * @tfile: Pointer to ttm_object_file of the creator.78 * NULL if the object was not created by a user request.79 * (kernel object).80 *81 * @refcount: Number of references to this object, not82 * including the hash entry. A reference to a base object can83 * only be held by a ref object.84 *85 * @refcount_release: A function to be called when there are86 * no more references to this object. This function should87 * destroy the object (or make sure destruction eventually happens),88 * and when it is called, the object has89 * already been taken out of the per-device hash. The parameter90 * "base" should be set to NULL by the function.91 *92 * @ref_obj_release: A function to be called when a reference object93 * with another ttm_ref_type than TTM_REF_USAGE is deleted.94 * This function may, for example, release a lock held by a user-space95 * process.96 *97 * This struct is intended to be used as a base struct for objects that98 * are visible to user-space. It provides a global name, race-safe99 * access and refcounting, minimal access control and hooks for unref actions.100 */101 102struct ttm_base_object {103 struct rcu_head rhead;104 struct ttm_object_file *tfile;105 struct kref refcount;106 void (*refcount_release) (struct ttm_base_object **base);107 u64 handle;108 enum ttm_object_type object_type;109 u32 shareable;110};111 112 113/**114 * struct ttm_prime_object - Modified base object that is prime-aware115 *116 * @base: struct ttm_base_object that we derive from117 * @mutex: Mutex protecting the @dma_buf member.118 * @size: Size of the dma_buf associated with this object119 * @real_type: Type of the underlying object. Needed since we're setting120 * the value of @base::object_type to ttm_prime_type121 * @dma_buf: Non ref-coutned pointer to a struct dma_buf created from this122 * object.123 * @refcount_release: The underlying object's release method. Needed since124 * we set @base::refcount_release to our own release method.125 */126 127struct ttm_prime_object {128 struct ttm_base_object base;129 struct mutex mutex;130 size_t size;131 enum ttm_object_type real_type;132 struct dma_buf *dma_buf;133 void (*refcount_release) (struct ttm_base_object **);134};135 136/**137 * ttm_base_object_init138 *139 * @tfile: Pointer to a struct ttm_object_file.140 * @base: The struct ttm_base_object to initialize.141 * @shareable: This object is shareable with other applications.142 * (different @tfile pointers.)143 * @type: The object type.144 * @refcount_release: See the struct ttm_base_object description.145 * @ref_obj_release: See the struct ttm_base_object description.146 *147 * Initializes a struct ttm_base_object.148 */149 150extern int ttm_base_object_init(struct ttm_object_file *tfile,151 struct ttm_base_object *base,152 bool shareable,153 enum ttm_object_type type,154 void (*refcount_release) (struct ttm_base_object155 **));156 157/**158 * ttm_base_object_lookup159 *160 * @tfile: Pointer to a struct ttm_object_file.161 * @key: Hash key162 *163 * Looks up a struct ttm_base_object with the key @key.164 */165 166extern struct ttm_base_object *ttm_base_object_lookup(struct ttm_object_file167 *tfile, uint64_t key);168 169/**170 * ttm_base_object_lookup_for_ref171 *172 * @tdev: Pointer to a struct ttm_object_device.173 * @key: Hash key174 *175 * Looks up a struct ttm_base_object with the key @key.176 * This function should only be used when the struct tfile associated with the177 * caller doesn't yet have a reference to the base object.178 */179 180extern struct ttm_base_object *181ttm_base_object_lookup_for_ref(struct ttm_object_device *tdev, uint64_t key);182 183/**184 * ttm_base_object_unref185 *186 * @p_base: Pointer to a pointer referencing a struct ttm_base_object.187 *188 * Decrements the base object refcount and clears the pointer pointed to by189 * p_base.190 */191 192extern void ttm_base_object_unref(struct ttm_base_object **p_base);193 194/**195 * ttm_ref_object_add.196 *197 * @tfile: A struct ttm_object_file representing the application owning the198 * ref_object.199 * @base: The base object to reference.200 * @ref_type: The type of reference.201 * @existed: Upon completion, indicates that an identical reference object202 * already existed, and the refcount was upped on that object instead.203 * @require_existed: Fail with -EPERM if an identical ref object didn't204 * already exist.205 *206 * Checks that the base object is shareable and adds a ref object to it.207 *208 * Adding a ref object to a base object is basically like referencing the209 * base object, but a user-space application holds the reference. When the210 * file corresponding to @tfile is closed, all its reference objects are211 * deleted. A reference object can have different types depending on what212 * it's intended for. It can be refcounting to prevent object destruction,213 * When user-space takes a lock, it can add a ref object to that lock to214 * make sure the lock is released if the application dies. A ref object215 * will hold a single reference on a base object.216 */217extern int ttm_ref_object_add(struct ttm_object_file *tfile,218 struct ttm_base_object *base,219 bool *existed,220 bool require_existed);221 222/**223 * ttm_ref_object_base_unref224 *225 * @key: Key representing the base object.226 * @ref_type: Ref type of the ref object to be dereferenced.227 *228 * Unreference a ref object with type @ref_type229 * on the base object identified by @key. If there are no duplicate230 * references, the ref object will be destroyed and the base object231 * will be unreferenced.232 */233extern int ttm_ref_object_base_unref(struct ttm_object_file *tfile,234 unsigned long key);235 236/**237 * ttm_object_file_init - initialize a struct ttm_object file238 *239 * @tdev: A struct ttm_object device this file is initialized on.240 *241 * This is typically called by the file_ops::open function.242 */243 244extern struct ttm_object_file *ttm_object_file_init(struct ttm_object_device245 *tdev);246 247/**248 * ttm_object_file_release - release data held by a ttm_object_file249 *250 * @p_tfile: Pointer to pointer to the ttm_object_file object to release.251 * *p_tfile will be set to NULL by this function.252 *253 * Releases all data associated by a ttm_object_file.254 * Typically called from file_ops::release. The caller must255 * ensure that there are no concurrent users of tfile.256 */257 258extern void ttm_object_file_release(struct ttm_object_file **p_tfile);259 260/**261 * ttm_object device init - initialize a struct ttm_object_device262 *263 * @ops: DMA buf ops for prime objects of this device.264 *265 * This function is typically called on device initialization to prepare266 * data structures needed for ttm base and ref objects.267 */268 269extern struct ttm_object_device *270ttm_object_device_init(const struct dma_buf_ops *ops);271 272/**273 * ttm_object_device_release - release data held by a ttm_object_device274 *275 * @p_tdev: Pointer to pointer to the ttm_object_device object to release.276 * *p_tdev will be set to NULL by this function.277 *278 * Releases all data associated by a ttm_object_device.279 * Typically called from driver::unload before the destruction of the280 * device private data structure.281 */282 283extern void ttm_object_device_release(struct ttm_object_device **p_tdev);284 285#define ttm_base_object_kfree(__object, __base)\286 kfree_rcu(__object, __base.rhead)287 288extern int ttm_prime_object_init(struct ttm_object_file *tfile,289 size_t size,290 struct ttm_prime_object *prime,291 enum ttm_object_type type,292 void (*refcount_release)293 (struct ttm_base_object **));294 295static inline enum ttm_object_type296ttm_base_object_type(struct ttm_base_object *base)297{298 return (base->object_type == ttm_prime_type) ?299 container_of(base, struct ttm_prime_object, base)->real_type :300 base->object_type;301}302extern int ttm_prime_fd_to_handle(struct ttm_object_file *tfile,303 int fd, u32 *handle);304extern int ttm_prime_handle_to_fd(struct ttm_object_file *tfile,305 uint32_t handle, uint32_t flags,306 int *prime_fd);307 308#define ttm_prime_object_kfree(__obj, __prime) \309 kfree_rcu(__obj, __prime.base.rhead)310 311static inline int ttm_bo_wait(struct ttm_buffer_object *bo, bool intr,312 bool no_wait)313{314 struct ttm_operation_ctx ctx = { intr, no_wait };315 316 return ttm_bo_wait_ctx(bo, &ctx);317}318 319#endif320