[linux-block.git] / include / rdma / uverbs_types.h

/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
/*
 * Copyright (c) 2017, Mellanox Technologies inc.  All rights reserved.
 */

#ifndef _UVERBS_TYPES_
#define _UVERBS_TYPES_

#include <linux/kernel.h>
#include <rdma/ib_verbs.h>

struct uverbs_obj_type;
struct uverbs_api_object;

enum rdma_lookup_mode {
	UVERBS_LOOKUP_READ,
	UVERBS_LOOKUP_WRITE,
	/*
	 * Destroy is like LOOKUP_WRITE, except that the uobject is not
	 * locked.  uobj_destroy is used to convert a LOOKUP_DESTROY lock into
	 * a LOOKUP_WRITE lock.
	 */
	UVERBS_LOOKUP_DESTROY,
};

/*
 * The following sequences are valid:
 * Success flow:
 *   alloc_begin
 *   alloc_commit
 *    [..]
 * Access flow:
 *   lookup_get(exclusive=false) & uverbs_try_lock_object
 *   lookup_put(exclusive=false) via rdma_lookup_put_uobject
 * Destruction flow:
 *   lookup_get(exclusive=true) & uverbs_try_lock_object
 *   remove_commit
 *   remove_handle (optional)
 *   lookup_put(exclusive=true) via rdma_lookup_put_uobject
 *
 * Allocate Error flow #1
 *   alloc_begin
 *   alloc_abort
 * Allocate Error flow #2
 *   alloc_begin
 *   remove_commit
 *   alloc_abort
 * Allocate Error flow #3
 *   alloc_begin
 *   alloc_commit (fails)
 *   remove_commit
 *   alloc_abort
 *
 * In all cases the caller must hold the ufile kref until alloc_commit or
 * alloc_abort returns.
 */
struct uverbs_obj_type_class {
	struct ib_uobject *(*alloc_begin)(const struct uverbs_api_object *obj,
					  struct uverbs_attr_bundle *attrs);
	/* This consumes the kref on uobj */
	void (*alloc_commit)(struct ib_uobject *uobj);
	/* This does not consume the kref on uobj */
	void (*alloc_abort)(struct ib_uobject *uobj);

	struct ib_uobject *(*lookup_get)(const struct uverbs_api_object *obj,
					 struct ib_uverbs_file *ufile, s64 id,
					 enum rdma_lookup_mode mode);
	void (*lookup_put)(struct ib_uobject *uobj, enum rdma_lookup_mode mode);
	/* This does not consume the kref on uobj */
	int __must_check (*destroy_hw)(struct ib_uobject *uobj,
				       enum rdma_remove_reason why,
				       struct uverbs_attr_bundle *attrs);
	void (*remove_handle)(struct ib_uobject *uobj);
	void (*swap_uobjects)(struct ib_uobject *obj_old,
			      struct ib_uobject *obj_new);
};

struct uverbs_obj_type {
	const struct uverbs_obj_type_class * const type_class;
	size_t	     obj_size;
};

/*
 * Objects type classes which support a detach state (object is still alive but
 * it's not attached to any context need to make sure:
 * (a) no call through to a driver after a detach is called
 * (b) detach isn't called concurrently with context_cleanup
 */

struct uverbs_obj_idr_type {
	/*
	 * In idr based objects, uverbs_obj_type_class points to a generic
	 * idr operations. In order to specialize the underlying types (e.g. CQ,
	 * QPs, etc.), we add destroy_object specific callbacks.
	 */
	struct uverbs_obj_type  type;

	/* Free driver resources from the uobject, make the driver uncallable,
	 * and move the uobject to the detached state. If the object was
	 * destroyed by the user's request, a failure should leave the uobject
	 * completely unchanged.
	 */
	int __must_check (*destroy_object)(struct ib_uobject *uobj,
					   enum rdma_remove_reason why,
					   struct uverbs_attr_bundle *attrs);
};

struct ib_uobject *rdma_lookup_get_uobject(const struct uverbs_api_object *obj,
					   struct ib_uverbs_file *ufile, s64 id,
					   enum rdma_lookup_mode mode,
					   struct uverbs_attr_bundle *attrs);
void rdma_lookup_put_uobject(struct ib_uobject *uobj,
			     enum rdma_lookup_mode mode);
struct ib_uobject *rdma_alloc_begin_uobject(const struct uverbs_api_object *obj,
					    struct uverbs_attr_bundle *attrs);
void rdma_alloc_abort_uobject(struct ib_uobject *uobj,
			      struct uverbs_attr_bundle *attrs,
			      bool hw_obj_valid);
void rdma_alloc_commit_uobject(struct ib_uobject *uobj,
			       struct uverbs_attr_bundle *attrs);
void rdma_assign_uobject(struct ib_uobject *to_uobj,
			 struct ib_uobject *new_uobj,
			 struct uverbs_attr_bundle *attrs);

/*
 * uverbs_uobject_get is called in order to increase the reference count on
 * an uobject. This is useful when a handler wants to keep the uobject's memory
 * alive, regardless if this uobject is still alive in the context's objects
 * repository. Objects are put via uverbs_uobject_put.
 */
static inline void uverbs_uobject_get(struct ib_uobject *uobject)
{
	kref_get(&uobject->ref);
}
void uverbs_uobject_put(struct ib_uobject *uobject);

struct uverbs_obj_fd_type {
	/*
	 * In fd based objects, uverbs_obj_type_ops points to generic
	 * fd operations. In order to specialize the underlying types (e.g.
	 * completion_channel), we use fops, name and flags for fd creation.
	 * destroy_object is called when the uobject is to be destroyed,
	 * because the driver is removed or the FD is closed.
	 */
	struct uverbs_obj_type  type;
	void (*destroy_object)(struct ib_uobject *uobj,
			       enum rdma_remove_reason why);
	const struct file_operations	*fops;
	const char			*name;
	int				flags;
};

extern const struct uverbs_obj_type_class uverbs_idr_class;
extern const struct uverbs_obj_type_class uverbs_fd_class;
int uverbs_uobject_fd_release(struct inode *inode, struct file *filp);

#define UVERBS_BUILD_BUG_ON(cond) (sizeof(char[1 - 2 * !!(cond)]) -	\
				   sizeof(char))
#define UVERBS_TYPE_ALLOC_FD(_obj_size, _destroy_object, _fops, _name, _flags) \
	((&((const struct uverbs_obj_fd_type)				\
	 {.type = {							\
		.type_class = &uverbs_fd_class,				\
		.obj_size = (_obj_size) +				\
			UVERBS_BUILD_BUG_ON((_obj_size) <               \
					    sizeof(struct ib_uobject)), \
	 },								\
	 .destroy_object = _destroy_object,				\
	 .fops = _fops,							\
	 .name = _name,							\
	 .flags = _flags}))->type)
#define UVERBS_TYPE_ALLOC_IDR_SZ(_size, _destroy_object)	\
	((&((const struct uverbs_obj_idr_type)				\
	 {.type = {							\
		.type_class = &uverbs_idr_class,			\
		.obj_size = (_size) +					\
			UVERBS_BUILD_BUG_ON((_size) <			\
					    sizeof(struct ib_uobject))	\
	 },								\
	 .destroy_object = _destroy_object,}))->type)
#define UVERBS_TYPE_ALLOC_IDR(_destroy_object)			\
	 UVERBS_TYPE_ALLOC_IDR_SZ(sizeof(struct ib_uobject),	\
				  _destroy_object)

#endif
Commit	Line	Data
6bf9d8f6	1	/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
38321256 MB	2	/*
38321256 MB	3	* Copyright (c) 2017, Mellanox Technologies inc. All rights reserved.
38321256 MB	4	*/
	5
	6	#ifndef _UVERBS_TYPES_
	7	#define _UVERBS_TYPES_
	8
	9	#include <linux/kernel.h>
	10	#include <rdma/ib_verbs.h>
	11
	12	struct uverbs_obj_type;
6b0d08f4	13	struct uverbs_api_object;
38321256	14
9867f5c6 JG	15	enum rdma_lookup_mode {
	16	UVERBS_LOOKUP_READ,
	17	UVERBS_LOOKUP_WRITE,
7452a3c7 JG	18	/*
	19	* Destroy is like LOOKUP_WRITE, except that the uobject is not
	20	* locked. uobj_destroy is used to convert a LOOKUP_DESTROY lock into
	21	* a LOOKUP_WRITE lock.
	22	*/
	23	UVERBS_LOOKUP_DESTROY,
9867f5c6 JG	24	};
9867f5c6 JG	25
87ad80ab JG	26	/*
	27	* The following sequences are valid:
	28	* Success flow:
	29	* alloc_begin
	30	* alloc_commit
	31	* [..]
	32	* Access flow:
	33	* lookup_get(exclusive=false) & uverbs_try_lock_object
	34	* lookup_put(exclusive=false) via rdma_lookup_put_uobject
	35	* Destruction flow:
	36	* lookup_get(exclusive=true) & uverbs_try_lock_object
	37	* remove_commit
0f50d88a	38	* remove_handle (optional)
87ad80ab JG	39	* lookup_put(exclusive=true) via rdma_lookup_put_uobject
	40	*
	41	* Allocate Error flow #1
	42	* alloc_begin
	43	* alloc_abort
	44	* Allocate Error flow #2
	45	* alloc_begin
	46	* remove_commit
	47	* alloc_abort
	48	* Allocate Error flow #3
	49	* alloc_begin
	50	* alloc_commit (fails)
	51	* remove_commit
	52	* alloc_abort
	53	*
	54	* In all cases the caller must hold the ufile kref until alloc_commit or
	55	* alloc_abort returns.
	56	*/
38321256	57	struct uverbs_obj_type_class {
6b0d08f4	58	struct ib_uobject (alloc_begin)(const struct uverbs_api_object *obj,
39e83af8	59	struct uverbs_attr_bundle *attrs);
87ad80ab	60	/* This consumes the kref on uobj */
849e1490	61	void (alloc_commit)(struct ib_uobject uobj);
87ad80ab	62	/* This does not consume the kref on uobj */
38321256 MB	63	void (alloc_abort)(struct ib_uobject uobj);
38321256 MB	64
6b0d08f4	65	struct ib_uobject (lookup_get)(const struct uverbs_api_object *obj,
1250c304	66	struct ib_uverbs_file *ufile, s64 id,
9867f5c6 JG	67	enum rdma_lookup_mode mode);
9867f5c6 JG	68	void (lookup_put)(struct ib_uobject uobj, enum rdma_lookup_mode mode);
87ad80ab	69	/* This does not consume the kref on uobj */
0f50d88a	70	int __must_check (destroy_hw)(struct ib_uobject uobj,
a6a3797d SR	71	enum rdma_remove_reason why,
a6a3797d SR	72	struct uverbs_attr_bundle *attrs);
0f50d88a	73	void (remove_handle)(struct ib_uobject uobj);
6e0954b1 JG	74	void (swap_uobjects)(struct ib_uobject obj_old,
6e0954b1 JG	75	struct ib_uobject *obj_new);
38321256 MB	76	};
	77
	78	struct uverbs_obj_type {
	79	const struct uverbs_obj_type_class * const type_class;
	80	size_t obj_size;
38321256 MB	81	};
	82
	83	/*
	84	* Objects type classes which support a detach state (object is still alive but
	85	* it's not attached to any context need to make sure:
	86	* (a) no call through to a driver after a detach is called
	87	* (b) detach isn't called concurrently with context_cleanup
	88	*/
	89
	90	struct uverbs_obj_idr_type {
	91	/*
	92	* In idr based objects, uverbs_obj_type_class points to a generic
	93	* idr operations. In order to specialize the underlying types (e.g. CQ,
	94	* QPs, etc.), we add destroy_object specific callbacks.
	95	*/
	96	struct uverbs_obj_type type;
	97
	98	/* Free driver resources from the uobject, make the driver uncallable,
	99	* and move the uobject to the detached state. If the object was
	100	* destroyed by the user's request, a failure should leave the uobject
	101	* completely unchanged.
	102	*/
	103	int __must_check (destroy_object)(struct ib_uobject uobj,
a6a3797d SR	104	enum rdma_remove_reason why,
a6a3797d SR	105	struct uverbs_attr_bundle *attrs);
38321256 MB	106	};
38321256 MB	107
6b0d08f4	108	struct ib_uobject rdma_lookup_get_uobject(const struct uverbs_api_object obj,
9867f5c6	109	struct ib_uverbs_file *ufile, s64 id,
70f06b26 SR	110	enum rdma_lookup_mode mode,
70f06b26 SR	111	struct uverbs_attr_bundle *attrs);
9867f5c6 JG	112	void rdma_lookup_put_uobject(struct ib_uobject *uobj,
9867f5c6 JG	113	enum rdma_lookup_mode mode);
6b0d08f4	114	struct ib_uobject rdma_alloc_begin_uobject(const struct uverbs_api_object obj,
70f06b26	115	struct uverbs_attr_bundle *attrs);
a6a3797d	116	void rdma_alloc_abort_uobject(struct ib_uobject *uobj,
0ac8903c JG	117	struct uverbs_attr_bundle *attrs,
0ac8903c JG	118	bool hw_obj_valid);
849e1490 JG	119	void rdma_alloc_commit_uobject(struct ib_uobject *uobj,
849e1490 JG	120	struct uverbs_attr_bundle *attrs);
6e0954b1 JG	121	void rdma_assign_uobject(struct ib_uobject *to_uobj,
	122	struct ib_uobject *new_uobj,
	123	struct uverbs_attr_bundle *attrs);
38321256	124
6898d1c6 JG	125	/*
	126	* uverbs_uobject_get is called in order to increase the reference count on
	127	* an uobject. This is useful when a handler wants to keep the uobject's memory
	128	* alive, regardless if this uobject is still alive in the context's objects
	129	* repository. Objects are put via uverbs_uobject_put.
	130	*/
	131	static inline void uverbs_uobject_get(struct ib_uobject *uobject)
	132	{
	133	kref_get(&uobject->ref);
	134	}
	135	void uverbs_uobject_put(struct ib_uobject *uobject);
	136
cf8966b3 MB	137	struct uverbs_obj_fd_type {
	138	/*
	139	* In fd based objects, uverbs_obj_type_ops points to generic
	140	* fd operations. In order to specialize the underlying types (e.g.
	141	* completion_channel), we use fops, name and flags for fd creation.
f7c8416c JG	142	* destroy_object is called when the uobject is to be destroyed,
f7c8416c JG	143	* because the driver is removed or the FD is closed.
cf8966b3 MB	144	*/
cf8966b3 MB	145	struct uverbs_obj_type type;
c5633a72 LR	146	void (destroy_object)(struct ib_uobject uobj,
c5633a72 LR	147	enum rdma_remove_reason why);
cf8966b3 MB	148	const struct file_operations *fops;
	149	const char *name;
	150	int flags;
	151	};
	152
6be60aed	153	extern const struct uverbs_obj_type_class uverbs_idr_class;
1e7710f3	154	extern const struct uverbs_obj_type_class uverbs_fd_class;
f7c8416c	155	int uverbs_uobject_fd_release(struct inode inode, struct file filp);
6be60aed MB	156
	157	#define UVERBS_BUILD_BUG_ON(cond) (sizeof(char[1 - 2 * !!(cond)]) - \
	158	sizeof(char))
f7c8416c	159	#define UVERBS_TYPE_ALLOC_FD(_obj_size, _destroy_object, _fops, _name, _flags) \
5009010f MB	160	((&((const struct uverbs_obj_fd_type) \
5009010f MB	161	{.type = { \
5009010f MB	162	.type_class = &uverbs_fd_class, \
5009010f MB	163	.obj_size = (_obj_size) + \
d0259e82 JG	164	UVERBS_BUILD_BUG_ON((_obj_size) < \
d0259e82 JG	165	sizeof(struct ib_uobject)), \
5009010f	166	}, \
f7c8416c	167	.destroy_object = _destroy_object, \
5009010f MB	168	.fops = _fops, \
	169	.name = _name, \
	170	.flags = _flags}))->type)
1c77483e	171	#define UVERBS_TYPE_ALLOC_IDR_SZ(_size, _destroy_object) \
5009010f MB	172	((&((const struct uverbs_obj_idr_type) \
5009010f MB	173	{.type = { \
6be60aed MB	174	.type_class = &uverbs_idr_class, \
6be60aed MB	175	.obj_size = (_size) + \
5009010f MB	176	UVERBS_BUILD_BUG_ON((_size) < \
	177	sizeof(struct ib_uobject)) \
	178	}, \
	179	.destroy_object = _destroy_object,}))->type)
1c77483e YH	180	#define UVERBS_TYPE_ALLOC_IDR(_destroy_object) \
1c77483e YH	181	UVERBS_TYPE_ALLOC_IDR_SZ(sizeof(struct ib_uobject), \
5009010f MB	182	_destroy_object)
5009010f MB	183
38321256	184	#endif