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Diffstat (limited to 'drivers/gpu/drm/vmwgfx/ttm_object.h')
| -rw-r--r-- | drivers/gpu/drm/vmwgfx/ttm_object.h | 310 |
1 files changed, 310 insertions, 0 deletions
diff --git a/drivers/gpu/drm/vmwgfx/ttm_object.h b/drivers/gpu/drm/vmwgfx/ttm_object.h new file mode 100644 index 000000000..8098a3846 --- /dev/null +++ b/drivers/gpu/drm/vmwgfx/ttm_object.h @@ -0,0 +1,310 @@ +/************************************************************************** + * + * Copyright (c) 2006-2022 VMware, Inc., Palo Alto, CA., USA + * All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sub license, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE + * USE OR OTHER DEALINGS IN THE SOFTWARE. + * + **************************************************************************/ +/* + * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com> + */ +/** @file ttm_object.h + * + * Base- and reference object implementation for the various + * ttm objects. Implements reference counting, minimal security checks + * and release on file close. + */ + +#ifndef _TTM_OBJECT_H_ +#define _TTM_OBJECT_H_ + +#include <linux/dma-buf.h> +#include <linux/kref.h> +#include <linux/list.h> +#include <linux/rcupdate.h> + +/** + * enum ttm_object_type + * + * One entry per ttm object type. + * Device-specific types should use the + * ttm_driver_typex types. + */ + +enum ttm_object_type { + ttm_fence_type, + ttm_lock_type, + ttm_prime_type, + ttm_driver_type0 = 256, + ttm_driver_type1, + ttm_driver_type2, + ttm_driver_type3, + ttm_driver_type4, + ttm_driver_type5 +}; + +struct ttm_object_file; +struct ttm_object_device; + +/** + * struct ttm_base_object + * + * @hash: hash entry for the per-device object hash. + * @type: derived type this object is base class for. + * @shareable: Other ttm_object_files can access this object. + * + * @tfile: Pointer to ttm_object_file of the creator. + * NULL if the object was not created by a user request. + * (kernel object). + * + * @refcount: Number of references to this object, not + * including the hash entry. A reference to a base object can + * only be held by a ref object. + * + * @refcount_release: A function to be called when there are + * no more references to this object. This function should + * destroy the object (or make sure destruction eventually happens), + * and when it is called, the object has + * already been taken out of the per-device hash. The parameter + * "base" should be set to NULL by the function. + * + * @ref_obj_release: A function to be called when a reference object + * with another ttm_ref_type than TTM_REF_USAGE is deleted. + * This function may, for example, release a lock held by a user-space + * process. + * + * This struct is intended to be used as a base struct for objects that + * are visible to user-space. It provides a global name, race-safe + * access and refcounting, minimal access control and hooks for unref actions. + */ + +struct ttm_base_object { + struct rcu_head rhead; + struct ttm_object_file *tfile; + struct kref refcount; + void (*refcount_release) (struct ttm_base_object **base); + u64 handle; + enum ttm_object_type object_type; + u32 shareable; +}; + + +/** + * struct ttm_prime_object - Modified base object that is prime-aware + * + * @base: struct ttm_base_object that we derive from + * @mutex: Mutex protecting the @dma_buf member. + * @size: Size of the dma_buf associated with this object + * @real_type: Type of the underlying object. Needed since we're setting + * the value of @base::object_type to ttm_prime_type + * @dma_buf: Non ref-coutned pointer to a struct dma_buf created from this + * object. + * @refcount_release: The underlying object's release method. Needed since + * we set @base::refcount_release to our own release method. + */ + +struct ttm_prime_object { + struct ttm_base_object base; + struct mutex mutex; + size_t size; + enum ttm_object_type real_type; + struct dma_buf *dma_buf; + void (*refcount_release) (struct ttm_base_object **); +}; + +/** + * ttm_base_object_init + * + * @tfile: Pointer to a struct ttm_object_file. + * @base: The struct ttm_base_object to initialize. + * @shareable: This object is shareable with other applications. + * (different @tfile pointers.) + * @type: The object type. + * @refcount_release: See the struct ttm_base_object description. + * @ref_obj_release: See the struct ttm_base_object description. + * + * Initializes a struct ttm_base_object. + */ + +extern int ttm_base_object_init(struct ttm_object_file *tfile, + struct ttm_base_object *base, + bool shareable, + enum ttm_object_type type, + void (*refcount_release) (struct ttm_base_object + **)); + +/** + * ttm_base_object_lookup + * + * @tfile: Pointer to a struct ttm_object_file. + * @key: Hash key + * + * Looks up a struct ttm_base_object with the key @key. + */ + +extern struct ttm_base_object *ttm_base_object_lookup(struct ttm_object_file + *tfile, uint64_t key); + +/** + * ttm_base_object_lookup_for_ref + * + * @tdev: Pointer to a struct ttm_object_device. + * @key: Hash key + * + * Looks up a struct ttm_base_object with the key @key. + * This function should only be used when the struct tfile associated with the + * caller doesn't yet have a reference to the base object. + */ + +extern struct ttm_base_object * +ttm_base_object_lookup_for_ref(struct ttm_object_device *tdev, uint64_t key); + +/** + * ttm_base_object_unref + * + * @p_base: Pointer to a pointer referencing a struct ttm_base_object. + * + * Decrements the base object refcount and clears the pointer pointed to by + * p_base. + */ + +extern void ttm_base_object_unref(struct ttm_base_object **p_base); + +/** + * ttm_ref_object_add. + * + * @tfile: A struct ttm_object_file representing the application owning the + * ref_object. + * @base: The base object to reference. + * @ref_type: The type of reference. + * @existed: Upon completion, indicates that an identical reference object + * already existed, and the refcount was upped on that object instead. + * @require_existed: Fail with -EPERM if an identical ref object didn't + * already exist. + * + * Checks that the base object is shareable and adds a ref object to it. + * + * Adding a ref object to a base object is basically like referencing the + * base object, but a user-space application holds the reference. When the + * file corresponding to @tfile is closed, all its reference objects are + * deleted. A reference object can have different types depending on what + * it's intended for. It can be refcounting to prevent object destruction, + * When user-space takes a lock, it can add a ref object to that lock to + * make sure the lock is released if the application dies. A ref object + * will hold a single reference on a base object. + */ +extern int ttm_ref_object_add(struct ttm_object_file *tfile, + struct ttm_base_object *base, + bool *existed, + bool require_existed); + +/** + * ttm_ref_object_base_unref + * + * @key: Key representing the base object. + * @ref_type: Ref type of the ref object to be dereferenced. + * + * Unreference a ref object with type @ref_type + * on the base object identified by @key. If there are no duplicate + * references, the ref object will be destroyed and the base object + * will be unreferenced. + */ +extern int ttm_ref_object_base_unref(struct ttm_object_file *tfile, + unsigned long key); + +/** + * ttm_object_file_init - initialize a struct ttm_object file + * + * @tdev: A struct ttm_object device this file is initialized on. + * + * This is typically called by the file_ops::open function. + */ + +extern struct ttm_object_file *ttm_object_file_init(struct ttm_object_device + *tdev); + +/** + * ttm_object_file_release - release data held by a ttm_object_file + * + * @p_tfile: Pointer to pointer to the ttm_object_file object to release. + * *p_tfile will be set to NULL by this function. + * + * Releases all data associated by a ttm_object_file. + * Typically called from file_ops::release. The caller must + * ensure that there are no concurrent users of tfile. + */ + +extern void ttm_object_file_release(struct ttm_object_file **p_tfile); + +/** + * ttm_object device init - initialize a struct ttm_object_device + * + * @ops: DMA buf ops for prime objects of this device. + * + * This function is typically called on device initialization to prepare + * data structures needed for ttm base and ref objects. + */ + +extern struct ttm_object_device * +ttm_object_device_init(const struct dma_buf_ops *ops); + +/** + * ttm_object_device_release - release data held by a ttm_object_device + * + * @p_tdev: Pointer to pointer to the ttm_object_device object to release. + * *p_tdev will be set to NULL by this function. + * + * Releases all data associated by a ttm_object_device. + * Typically called from driver::unload before the destruction of the + * device private data structure. + */ + +extern void ttm_object_device_release(struct ttm_object_device **p_tdev); + +#define ttm_base_object_kfree(__object, __base)\ + kfree_rcu(__object, __base.rhead) + +extern int ttm_prime_object_init(struct ttm_object_file *tfile, + size_t size, + struct ttm_prime_object *prime, + bool shareable, + enum ttm_object_type type, + void (*refcount_release) + (struct ttm_base_object **)); + +static inline enum ttm_object_type +ttm_base_object_type(struct ttm_base_object *base) +{ + return (base->object_type == ttm_prime_type) ? + container_of(base, struct ttm_prime_object, base)->real_type : + base->object_type; +} +extern int ttm_prime_fd_to_handle(struct ttm_object_file *tfile, + int fd, u32 *handle); +extern int ttm_prime_handle_to_fd(struct ttm_object_file *tfile, + uint32_t handle, uint32_t flags, + int *prime_fd); + +#define ttm_prime_object_kfree(__obj, __prime) \ + kfree_rcu(__obj, __prime.base.rhead) + +#endif |