[linux-2.6-block.git] / include / rdma / uverbs_ioctl.h

/*
 * Copyright (c) 2017, Mellanox Technologies inc.  All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * 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
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * 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.
 */

#ifndef _UVERBS_IOCTL_
#define _UVERBS_IOCTL_

#include <rdma/uverbs_types.h>
#include <linux/uaccess.h>
#include <rdma/rdma_user_ioctl.h>
#include <rdma/ib_user_ioctl_verbs.h>
#include <rdma/ib_user_ioctl_cmds.h>

/*
 * =======================================
 *	Verbs action specifications
 * =======================================
 */

enum uverbs_attr_type {
	UVERBS_ATTR_TYPE_NA,
	UVERBS_ATTR_TYPE_PTR_IN,
	UVERBS_ATTR_TYPE_PTR_OUT,
	UVERBS_ATTR_TYPE_IDR,
	UVERBS_ATTR_TYPE_FD,
	UVERBS_ATTR_TYPE_ENUM_IN,
};

enum uverbs_obj_access {
	UVERBS_ACCESS_READ,
	UVERBS_ACCESS_WRITE,
	UVERBS_ACCESS_NEW,
	UVERBS_ACCESS_DESTROY
};

enum {
	UVERBS_ATTR_SPEC_F_MANDATORY	= 1U << 0,
	/* Support extending attributes by length, validate all unknown size == zero  */
	UVERBS_ATTR_SPEC_F_MIN_SZ_OR_ZERO = 1U << 1,
};

/* Specification of a single attribute inside the ioctl message */
struct uverbs_attr_spec {
	union {
		/* Header shared by all following union members - to reduce space. */
		struct {
			enum uverbs_attr_type		type;
			/* Combination of bits from enum UVERBS_ATTR_SPEC_F_XXXX */
			u8				flags;
		};
		struct {
			enum uverbs_attr_type		type;
			/* Combination of bits from enum UVERBS_ATTR_SPEC_F_XXXX */
			u8				flags;
			/* Current known size to kernel */
			u16				len;
			/* User isn't allowed to provide something < min_len */
			u16				min_len;
		} ptr;
		struct {
			enum uverbs_attr_type		type;
			/* Combination of bits from enum UVERBS_ATTR_SPEC_F_XXXX */
			u8				flags;
			/*
			 * higher bits mean the namespace and lower bits mean
			 * the type id within the namespace.
			 */
			u16			obj_type;
			u8			access;
		} obj;
		struct {
			enum uverbs_attr_type		type;
			/* Combination of bits from enum UVERBS_ATTR_SPEC_F_XXXX */
			u8				flags;
			u8				num_elems;
			/*
			 * The enum attribute can select one of the attributes
			 * contained in the ids array. Currently only PTR_IN
			 * attributes are supported in the ids array.
			 */
			const struct uverbs_attr_spec	*ids;
		} enum_def;
	};
};

struct uverbs_attr_spec_hash {
	size_t				num_attrs;
	unsigned long			*mandatory_attrs_bitmask;
	struct uverbs_attr_spec		attrs[0];
};

struct uverbs_attr_bundle;
struct ib_uverbs_file;

enum {
	/*
	 * Action marked with this flag creates a context (or root for all
	 * objects).
	 */
	UVERBS_ACTION_FLAG_CREATE_ROOT = 1U << 0,
};

struct uverbs_method_spec {
	/* Combination of bits from enum UVERBS_ACTION_FLAG_XXXX */
	u32						flags;
	size_t						num_buckets;
	size_t						num_child_attrs;
	int (*handler)(struct ib_device *ib_dev, struct ib_uverbs_file *ufile,
		       struct uverbs_attr_bundle *ctx);
	struct uverbs_attr_spec_hash		*attr_buckets[0];
};

struct uverbs_method_spec_hash {
	size_t					num_methods;
	struct uverbs_method_spec		*methods[0];
};

struct uverbs_object_spec {
	const struct uverbs_obj_type		*type_attrs;
	size_t					num_buckets;
	struct uverbs_method_spec_hash		*method_buckets[0];
};

struct uverbs_object_spec_hash {
	size_t					num_objects;
	struct uverbs_object_spec		*objects[0];
};

struct uverbs_root_spec {
	size_t					num_buckets;
	struct uverbs_object_spec_hash		*object_buckets[0];
};

/*
 * =======================================
 *	Verbs definitions
 * =======================================
 */

struct uverbs_attr_def {
	u16                           id;
	struct uverbs_attr_spec       attr;
};

struct uverbs_method_def {
	u16                                  id;
	/* Combination of bits from enum UVERBS_ACTION_FLAG_XXXX */
	u32				     flags;
	size_t				     num_attrs;
	const struct uverbs_attr_def * const (*attrs)[];
	int (*handler)(struct ib_device *ib_dev, struct ib_uverbs_file *ufile,
		       struct uverbs_attr_bundle *ctx);
};

struct uverbs_object_def {
	u16					 id;
	const struct uverbs_obj_type	        *type_attrs;
	size_t				         num_methods;
	const struct uverbs_method_def * const (*methods)[];
};

struct uverbs_object_tree_def {
	size_t					 num_objects;
	const struct uverbs_object_def * const (*objects)[];
};

#define UA_FLAGS(_flags)  .flags = _flags
#define __UVERBS_ATTR0(_id, _type, _fld, _attr, ...)              \
	((const struct uverbs_attr_def)				  \
	 {.id = _id, .attr = {{._fld = {.type = _type, _attr, .flags = 0, } }, } })
#define __UVERBS_ATTR1(_id, _type, _fld, _attr, _extra1, ...)      \
	((const struct uverbs_attr_def)				  \
	 {.id = _id, .attr = {{._fld = {.type = _type, _attr, _extra1 } },} })
#define __UVERBS_ATTR2(_id, _type, _fld, _attr, _extra1, _extra2)    \
	((const struct uverbs_attr_def)				  \
	 {.id = _id, .attr = {{._fld = {.type = _type, _attr, _extra1, _extra2 } },} })
#define __UVERBS_ATTR(_id, _type, _fld, _attr, _extra1, _extra2, _n, ...)	\
	__UVERBS_ATTR##_n(_id, _type, _fld, _attr, _extra1, _extra2)

#define UVERBS_ATTR_TYPE(_type)					\
	.min_len = sizeof(_type), .len = sizeof(_type)
#define UVERBS_ATTR_STRUCT(_type, _last)			\
	.min_len = ((uintptr_t)(&((_type *)0)->_last + 1)), .len = sizeof(_type)
#define UVERBS_ATTR_SIZE(_min_len, _len)			\
	.min_len = _min_len, .len = _len

/*
 * In new compiler, UVERBS_ATTR could be simplified by declaring it as
 * [_id] = {.type = _type, .len = _len, ##__VA_ARGS__}
 * But since we support older compilers too, we need the more complex code.
 */
#define UVERBS_ATTR(_id, _type, _fld, _attr, ...)			\
	__UVERBS_ATTR(_id, _type, _fld, _attr, ##__VA_ARGS__, 2, 1, 0)
#define UVERBS_ATTR_PTR_IN_SZ(_id, _len, ...)				\
	UVERBS_ATTR(_id, UVERBS_ATTR_TYPE_PTR_IN, ptr, _len, ##__VA_ARGS__)
/* If sizeof(_type) <= sizeof(u64), this will be inlined rather than a pointer */
#define UVERBS_ATTR_PTR_IN(_id, _type, ...)				\
	UVERBS_ATTR_PTR_IN_SZ(_id, _type, ##__VA_ARGS__)
#define UVERBS_ATTR_PTR_OUT_SZ(_id, _len, ...)				\
	UVERBS_ATTR(_id, UVERBS_ATTR_TYPE_PTR_OUT, ptr, _len, ##__VA_ARGS__)
#define UVERBS_ATTR_PTR_OUT(_id, _type, ...)				\
	UVERBS_ATTR_PTR_OUT_SZ(_id, _type, ##__VA_ARGS__)
#define UVERBS_ATTR_ENUM_IN(_id, _enum_arr, ...)			\
	UVERBS_ATTR(_id, UVERBS_ATTR_TYPE_ENUM_IN, enum_def,		\
		    .ids = (_enum_arr),					\
		    .num_elems = ARRAY_SIZE(_enum_arr), ##__VA_ARGS__)

/*
 * In new compiler, UVERBS_ATTR_IDR (and FD) could be simplified by declaring
 * it as
 * {.id = _id,								\
 *  .attr {.type = __obj_class,						\
 *         .obj = {.obj_type = _idr_type,				\
 *                       .access = _access                              \
 *                }, ##__VA_ARGS__ } }
 * But since we support older compilers too, we need the more complex code.
 */
#define ___UVERBS_ATTR_OBJ0(_id, _obj_class, _obj_type, _access, ...)\
	((const struct uverbs_attr_def)					\
	{.id = _id,							\
	 .attr = { {.obj = {.type = _obj_class, .obj_type = _obj_type,	\
			    .access = _access, .flags = 0 } }, } })
#define ___UVERBS_ATTR_OBJ1(_id, _obj_class, _obj_type, _access, _flags)\
	((const struct uverbs_attr_def)					\
	{.id = _id,							\
	.attr = { {.obj = {.type = _obj_class, .obj_type = _obj_type,	\
			   .access = _access, _flags} }, } })
#define ___UVERBS_ATTR_OBJ(_id, _obj_class, _obj_type, _access, _flags, \
			   _n, ...)					\
	___UVERBS_ATTR_OBJ##_n(_id, _obj_class, _obj_type, _access, _flags)
#define __UVERBS_ATTR_OBJ(_id, _obj_class, _obj_type, _access, ...)	\
	___UVERBS_ATTR_OBJ(_id, _obj_class, _obj_type, _access,		\
			   ##__VA_ARGS__, 1, 0)
#define UVERBS_ATTR_IDR(_id, _idr_type, _access, ...)			 \
	__UVERBS_ATTR_OBJ(_id, UVERBS_ATTR_TYPE_IDR, _idr_type, _access,\
			  ##__VA_ARGS__)
#define UVERBS_ATTR_FD(_id, _fd_type, _access, ...)			\
	__UVERBS_ATTR_OBJ(_id, UVERBS_ATTR_TYPE_FD, _fd_type,		\
			  (_access) + BUILD_BUG_ON_ZERO(		\
				(_access) != UVERBS_ACCESS_NEW &&	\
				(_access) != UVERBS_ACCESS_READ),	\
			  ##__VA_ARGS__)
#define DECLARE_UVERBS_ATTR_SPEC(_name, ...)				\
	const struct uverbs_attr_def _name = __VA_ARGS__

#define DECLARE_UVERBS_ENUM(_name, ...)					\
	const struct uverbs_enum_spec _name = {				\
		.len = ARRAY_SIZE(((struct uverbs_attr_spec[]){__VA_ARGS__})),\
		.ids = {__VA_ARGS__},					\
	}
#define _UVERBS_METHOD_ATTRS_SZ(...)					\
	(sizeof((const struct uverbs_attr_def * const []){__VA_ARGS__}) /\
	 sizeof(const struct uverbs_attr_def *))
#define _UVERBS_METHOD(_id, _handler, _flags, ...)			\
	((const struct uverbs_method_def) {				\
	 .id = _id,							\
	 .flags = _flags,						\
	 .handler = _handler,						\
	 .num_attrs = _UVERBS_METHOD_ATTRS_SZ(__VA_ARGS__),		\
	 .attrs = &(const struct uverbs_attr_def * const []){__VA_ARGS__} })
#define DECLARE_UVERBS_METHOD(_name, _id, _handler, ...)		\
	const struct uverbs_method_def _name =				\
		_UVERBS_METHOD(_id, _handler, 0, ##__VA_ARGS__)
#define DECLARE_UVERBS_CTX_METHOD(_name, _id, _handler, _flags, ...)	\
	const struct uverbs_method_def _name =				\
		_UVERBS_METHOD(_id, _handler,				\
			       UVERBS_ACTION_FLAG_CREATE_ROOT,		\
			       ##__VA_ARGS__)
#define _UVERBS_OBJECT_METHODS_SZ(...)					\
	(sizeof((const struct uverbs_method_def * const []){__VA_ARGS__}) / \
	 sizeof(const struct uverbs_method_def *))
#define _UVERBS_OBJECT(_id, _type_attrs, ...)				\
	((const struct uverbs_object_def) {				\
	 .id = _id,							\
	 .type_attrs = _type_attrs,					\
	 .num_methods = _UVERBS_OBJECT_METHODS_SZ(__VA_ARGS__),		\
	 .methods = &(const struct uverbs_method_def * const []){__VA_ARGS__} })
#define DECLARE_UVERBS_OBJECT(_name, _id, _type_attrs, ...)		\
	const struct uverbs_object_def _name =				\
		_UVERBS_OBJECT(_id, _type_attrs, ##__VA_ARGS__)
#define _UVERBS_TREE_OBJECTS_SZ(...)					\
	(sizeof((const struct uverbs_object_def * const []){__VA_ARGS__}) / \
	 sizeof(const struct uverbs_object_def *))
#define _UVERBS_OBJECT_TREE(...)					\
	((const struct uverbs_object_tree_def) {			\
	 .num_objects = _UVERBS_TREE_OBJECTS_SZ(__VA_ARGS__),		\
	 .objects = &(const struct uverbs_object_def * const []){__VA_ARGS__} })
#define DECLARE_UVERBS_OBJECT_TREE(_name, ...)				\
	const struct uverbs_object_tree_def _name =			\
		_UVERBS_OBJECT_TREE(__VA_ARGS__)

/* =================================================
 *              Parsing infrastructure
 * =================================================
 */

struct uverbs_ptr_attr {
	u64		data;
	u16		len;
	/* Combination of bits from enum UVERBS_ATTR_F_XXXX */
	u16		flags;
	u8		enum_id;
};

struct uverbs_obj_attr {
	/* pointer to the kernel descriptor -> type, access, etc */
	const struct uverbs_obj_type	*type;
	struct ib_uobject		*uobject;
	/* fd or id in idr of this object */
	int				id;
};

struct uverbs_attr {
	/*
	 * pointer to the user-space given attribute, in order to write the
	 * new uobject's id or update flags.
	 */
	struct ib_uverbs_attr __user	*uattr;
	union {
		struct uverbs_ptr_attr	ptr_attr;
		struct uverbs_obj_attr	obj_attr;
	};
};

struct uverbs_attr_bundle_hash {
	/* if bit i is set, it means attrs[i] contains valid information */
	unsigned long *valid_bitmap;
	size_t num_attrs;
	/*
	 * arrays of attributes, each element corresponds to the specification
	 * of the attribute in the same index.
	 */
	struct uverbs_attr *attrs;
};

struct uverbs_attr_bundle {
	size_t				num_buckets;
	struct uverbs_attr_bundle_hash  hash[];
};

static inline bool uverbs_attr_is_valid_in_hash(const struct uverbs_attr_bundle_hash *attrs_hash,
						unsigned int idx)
{
	return test_bit(idx, attrs_hash->valid_bitmap);
}

static inline bool uverbs_attr_is_valid(const struct uverbs_attr_bundle *attrs_bundle,
					unsigned int idx)
{
	u16 idx_bucket = idx >>	UVERBS_ID_NS_SHIFT;

	if (attrs_bundle->num_buckets <= idx_bucket)
		return false;

	return uverbs_attr_is_valid_in_hash(&attrs_bundle->hash[idx_bucket],
					    idx & ~UVERBS_ID_NS_MASK);
}

#define IS_UVERBS_COPY_ERR(_ret)		((_ret) && (_ret) != -ENOENT)

static inline const struct uverbs_attr *uverbs_attr_get(const struct uverbs_attr_bundle *attrs_bundle,
							u16 idx)
{
	u16 idx_bucket = idx >>	UVERBS_ID_NS_SHIFT;

	if (!uverbs_attr_is_valid(attrs_bundle, idx))
		return ERR_PTR(-ENOENT);

	return &attrs_bundle->hash[idx_bucket].attrs[idx & ~UVERBS_ID_NS_MASK];
}

static inline int uverbs_attr_get_enum_id(const struct uverbs_attr_bundle *attrs_bundle,
					  u16 idx)
{
	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);

	if (IS_ERR(attr))
		return PTR_ERR(attr);

	return attr->ptr_attr.enum_id;
}

static inline void *uverbs_attr_get_obj(const struct uverbs_attr_bundle *attrs_bundle,
					u16 idx)
{
	struct ib_uobject *uobj =
		uverbs_attr_get(attrs_bundle, idx)->obj_attr.uobject;

	if (IS_ERR(uobj))
		return uobj;

	return uobj->object;
}

static inline int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle,
				 size_t idx, const void *from, size_t size)
{
	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
	u16 flags;
	size_t min_size;

	if (IS_ERR(attr))
		return PTR_ERR(attr);

	min_size = min_t(size_t, attr->ptr_attr.len, size);
	if (copy_to_user(u64_to_user_ptr(attr->ptr_attr.data), from, min_size))
		return -EFAULT;

	flags = attr->ptr_attr.flags | UVERBS_ATTR_F_VALID_OUTPUT;
	if (put_user(flags, &attr->uattr->flags))
		return -EFAULT;

	return 0;
}

static inline bool uverbs_attr_ptr_is_inline(const struct uverbs_attr *attr)
{
	return attr->ptr_attr.len <= sizeof(attr->ptr_attr.data);
}

static inline int _uverbs_copy_from(void *to,
				    const struct uverbs_attr_bundle *attrs_bundle,
				    size_t idx,
				    size_t size)
{
	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);

	if (IS_ERR(attr))
		return PTR_ERR(attr);

	/*
	 * Validation ensures attr->ptr_attr.len >= size. If the caller is
	 * using UVERBS_ATTR_SPEC_F_MIN_SZ_OR_ZERO then it must call
	 * uverbs_copy_from_or_zero.
	 */
	if (unlikely(size < attr->ptr_attr.len))
		return -EINVAL;

	if (uverbs_attr_ptr_is_inline(attr))
		memcpy(to, &attr->ptr_attr.data, attr->ptr_attr.len);
	else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
				attr->ptr_attr.len))
		return -EFAULT;

	return 0;
}

static inline int _uverbs_copy_from_or_zero(void *to,
					    const struct uverbs_attr_bundle *attrs_bundle,
					    size_t idx,
					    size_t size)
{
	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
	size_t min_size;

	if (IS_ERR(attr))
		return PTR_ERR(attr);

	min_size = min_t(size_t, size, attr->ptr_attr.len);

	if (uverbs_attr_ptr_is_inline(attr))
		memcpy(to, &attr->ptr_attr.data, min_size);
	else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
				min_size))
		return -EFAULT;

	if (size > min_size)
		memset(to + min_size, 0, size - min_size);

	return 0;
}

#define uverbs_copy_from(to, attrs_bundle, idx)				      \
	_uverbs_copy_from(to, attrs_bundle, idx, sizeof(*to))

#define uverbs_copy_from_or_zero(to, attrs_bundle, idx)			      \
	_uverbs_copy_from_or_zero(to, attrs_bundle, idx, sizeof(*to))

/* =================================================
 *	 Definitions -> Specs infrastructure
 * =================================================
 */

/*
 * uverbs_alloc_spec_tree - Merges different common and driver specific feature
 *	into one parsing tree that every uverbs command will be parsed upon.
 *
 * @num_trees: Number of trees in the array @trees.
 * @trees: Array of pointers to tree root definitions to merge. Each such tree
 *	   possibly contains objects, methods and attributes definitions.
 *
 * Returns:
 *	uverbs_root_spec *: The root of the merged parsing tree.
 *	On error, we return an error code. Error is checked via IS_ERR.
 *
 * The following merges could take place:
 * a. Two trees representing the same method with different handler
 *	-> We take the handler of the tree that its handler != NULL
 *	   and its index in the trees array is greater. The incentive for that
 *	   is that developers are expected to first merge common trees and then
 *	   merge trees that gives specialized the behaviour.
 * b. Two trees representing the same object with different
 *    type_attrs (struct uverbs_obj_type):
 *	-> We take the type_attrs of the tree that its type_attr != NULL
 *	   and its index in the trees array is greater. This could be used
 *	   in order to override the free function, allocation size, etc.
 * c. Two trees representing the same method attribute (same id but possibly
 *    different attributes):
 *	-> ERROR (-ENOENT), we believe that's not the programmer's intent.
 *
 * An object without any methods is considered invalid and will abort the
 * function with -ENOENT error.
 */
#if IS_ENABLED(CONFIG_INFINIBAND_USER_ACCESS)
struct uverbs_root_spec *uverbs_alloc_spec_tree(unsigned int num_trees,
						const struct uverbs_object_tree_def **trees);
void uverbs_free_spec_tree(struct uverbs_root_spec *root);
#else
static inline struct uverbs_root_spec *uverbs_alloc_spec_tree(unsigned int num_trees,
							      const struct uverbs_object_tree_def **trees)
{
	return NULL;
}

static inline void uverbs_free_spec_tree(struct uverbs_root_spec *root)
{
}
#endif

#endif
Commit	Line	Data
a0aa309c MB	1	/*
	2	* Copyright (c) 2017, Mellanox Technologies inc. All rights reserved.
	3	*
	4	* This software is available to you under a choice of one of two
	5	* licenses. You may choose to be licensed under the terms of the GNU
	6	* General Public License (GPL) Version 2, available from the file
	7	* COPYING in the main directory of this source tree, or the
	8	* OpenIB.org BSD license below:
	9	*
	10	* Redistribution and use in source and binary forms, with or
	11	* without modification, are permitted provided that the following
	12	* conditions are met:
	13	*
	14	* - Redistributions of source code must retain the above
	15	* copyright notice, this list of conditions and the following
	16	* disclaimer.
	17	*
	18	* - Redistributions in binary form must reproduce the above
	19	* copyright notice, this list of conditions and the following
	20	* disclaimer in the documentation and/or other materials
	21	* provided with the distribution.
	22	*
	23	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	24	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	25	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	26	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	27	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	28	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	29	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	30	* SOFTWARE.
	31	*/
	32
	33	#ifndef _UVERBS_IOCTL_
	34	#define _UVERBS_IOCTL_
	35
	36	#include <rdma/uverbs_types.h>
35410306 MB	37	#include <linux/uaccess.h>
35410306 MB	38	#include <rdma/rdma_user_ioctl.h>
d70724f1	39	#include <rdma/ib_user_ioctl_verbs.h>
1f7ff9d5	40	#include <rdma/ib_user_ioctl_cmds.h>
a0aa309c MB	41
	42	/*
	43	* =======================================
	44	* Verbs action specifications
	45	* =======================================
	46	*/
	47
f43dbebf MB	48	enum uverbs_attr_type {
f43dbebf MB	49	UVERBS_ATTR_TYPE_NA,
fac9658c MB	50	UVERBS_ATTR_TYPE_PTR_IN,
fac9658c MB	51	UVERBS_ATTR_TYPE_PTR_OUT,
f43dbebf MB	52	UVERBS_ATTR_TYPE_IDR,
f43dbebf MB	53	UVERBS_ATTR_TYPE_FD,
494c5580	54	UVERBS_ATTR_TYPE_ENUM_IN,
f43dbebf MB	55	};
f43dbebf MB	56
a0aa309c MB	57	enum uverbs_obj_access {
	58	UVERBS_ACCESS_READ,
	59	UVERBS_ACCESS_WRITE,
	60	UVERBS_ACCESS_NEW,
	61	UVERBS_ACCESS_DESTROY
	62	};
	63
fac9658c MB	64	enum {
fac9658c MB	65	UVERBS_ATTR_SPEC_F_MANDATORY = 1U << 0,
c66db311 MB	66	/* Support extending attributes by length, validate all unknown size == zero */
c66db311 MB	67	UVERBS_ATTR_SPEC_F_MIN_SZ_OR_ZERO = 1U << 1,
fac9658c MB	68	};
fac9658c MB	69
1f07e08f	70	/* Specification of a single attribute inside the ioctl message */
f43dbebf	71	struct uverbs_attr_spec {
fac9658c	72	union {
1f07e08f	73	/* Header shared by all following union members - to reduce space. */
fac9658c	74	struct {
1f07e08f MB	75	enum uverbs_attr_type type;
	76	/* Combination of bits from enum UVERBS_ATTR_SPEC_F_XXXX */
	77	u8 flags;
	78	};
	79	struct {
	80	enum uverbs_attr_type type;
	81	/* Combination of bits from enum UVERBS_ATTR_SPEC_F_XXXX */
	82	u8 flags;
c66db311	83	/* Current known size to kernel */
1f07e08f	84	u16 len;
c66db311 MB	85	/* User isn't allowed to provide something < min_len */
c66db311 MB	86	u16 min_len;
1f07e08f MB	87	} ptr;
	88	struct {
	89	enum uverbs_attr_type type;
	90	/* Combination of bits from enum UVERBS_ATTR_SPEC_F_XXXX */
	91	u8 flags;
fac9658c MB	92	/*
	93	* higher bits mean the namespace and lower bits mean
	94	* the type id within the namespace.
	95	*/
	96	u16 obj_type;
	97	u8 access;
	98	} obj;
494c5580 MB	99	struct {
	100	enum uverbs_attr_type type;
	101	/* Combination of bits from enum UVERBS_ATTR_SPEC_F_XXXX */
	102	u8 flags;
	103	u8 num_elems;
	104	/*
	105	* The enum attribute can select one of the attributes
	106	* contained in the ids array. Currently only PTR_IN
	107	* attributes are supported in the ids array.
	108	*/
	109	const struct uverbs_attr_spec *ids;
	110	} enum_def;
fac9658c	111	};
f43dbebf MB	112	};
	113
	114	struct uverbs_attr_spec_hash {
	115	size_t num_attrs;
fac9658c	116	unsigned long *mandatory_attrs_bitmask;
f43dbebf MB	117	struct uverbs_attr_spec attrs[0];
	118	};
	119
fac9658c MB	120	struct uverbs_attr_bundle;
	121	struct ib_uverbs_file;
	122
	123	enum {
	124	/*
	125	* Action marked with this flag creates a context (or root for all
	126	* objects).
	127	*/
	128	UVERBS_ACTION_FLAG_CREATE_ROOT = 1U << 0,
	129	};
	130
	131	struct uverbs_method_spec {
	132	/* Combination of bits from enum UVERBS_ACTION_FLAG_XXXX */
	133	u32 flags;
	134	size_t num_buckets;
	135	size_t num_child_attrs;
	136	int (handler)(struct ib_device ib_dev, struct ib_uverbs_file *ufile,
	137	struct uverbs_attr_bundle *ctx);
	138	struct uverbs_attr_spec_hash *attr_buckets[0];
	139	};
	140
	141	struct uverbs_method_spec_hash {
	142	size_t num_methods;
	143	struct uverbs_method_spec *methods[0];
	144	};
	145
	146	struct uverbs_object_spec {
	147	const struct uverbs_obj_type *type_attrs;
	148	size_t num_buckets;
	149	struct uverbs_method_spec_hash *method_buckets[0];
	150	};
	151
	152	struct uverbs_object_spec_hash {
	153	size_t num_objects;
	154	struct uverbs_object_spec *objects[0];
	155	};
	156
	157	struct uverbs_root_spec {
	158	size_t num_buckets;
	159	struct uverbs_object_spec_hash *object_buckets[0];
	160	};
	161
5009010f MB	162	/*
	163	* =======================================
	164	* Verbs definitions
	165	* =======================================
	166	*/
	167
09e3ebf8 MB	168	struct uverbs_attr_def {
	169	u16 id;
	170	struct uverbs_attr_spec attr;
	171	};
	172
	173	struct uverbs_method_def {
	174	u16 id;
	175	/* Combination of bits from enum UVERBS_ACTION_FLAG_XXXX */
	176	u32 flags;
	177	size_t num_attrs;
	178	const struct uverbs_attr_def * const (*attrs)[];
	179	int (handler)(struct ib_device ib_dev, struct ib_uverbs_file *ufile,
	180	struct uverbs_attr_bundle *ctx);
	181	};
	182
5009010f	183	struct uverbs_object_def {
09e3ebf8	184	u16 id;
5009010f	185	const struct uverbs_obj_type *type_attrs;
09e3ebf8 MB	186	size_t num_methods;
	187	const struct uverbs_method_def * const (*methods)[];
	188	};
	189
	190	struct uverbs_object_tree_def {
	191	size_t num_objects;
	192	const struct uverbs_object_def * const (*objects)[];
5009010f MB	193	};
5009010f MB	194
35410306	195	#define UA_FLAGS(_flags) .flags = _flags
c66db311	196	#define __UVERBS_ATTR0(_id, _type, _fld, _attr, ...) \
35410306	197	((const struct uverbs_attr_def) \
c66db311 MB	198	{.id = _id, .attr = {{._fld = {.type = _type, _attr, .flags = 0, } }, } })
c66db311 MB	199	#define __UVERBS_ATTR1(_id, _type, _fld, _attr, _extra1, ...) \
35410306	200	((const struct uverbs_attr_def) \
c66db311 MB	201	{.id = _id, .attr = {{._fld = {.type = _type, _attr, _extra1 } },} })
	202	#define __UVERBS_ATTR2(_id, _type, _fld, _attr, _extra1, _extra2) \
	203	((const struct uverbs_attr_def) \
	204	{.id = _id, .attr = {{._fld = {.type = _type, _attr, _extra1, _extra2 } },} })
	205	#define __UVERBS_ATTR(_id, _type, _fld, _attr, _extra1, _extra2, _n, ...) \
	206	__UVERBS_ATTR##_n(_id, _type, _fld, _attr, _extra1, _extra2)
	207
	208	#define UVERBS_ATTR_TYPE(_type) \
	209	.min_len = sizeof(_type), .len = sizeof(_type)
	210	#define UVERBS_ATTR_STRUCT(_type, _last) \
	211	.min_len = ((uintptr_t)(&((_type *)0)->_last + 1)), .len = sizeof(_type)
	212	#define UVERBS_ATTR_SIZE(_min_len, _len) \
	213	.min_len = _min_len, .len = _len
	214
35410306 MB	215	/*
	216	* In new compiler, UVERBS_ATTR could be simplified by declaring it as
	217	* [_id] = {.type = _type, .len = _len, ##__VA_ARGS__}
	218	* But since we support older compilers too, we need the more complex code.
	219	*/
c66db311 MB	220	#define UVERBS_ATTR(_id, _type, _fld, _attr, ...) \
c66db311 MB	221	__UVERBS_ATTR(_id, _type, _fld, _attr, ##__VA_ARGS__, 2, 1, 0)
35410306	222	#define UVERBS_ATTR_PTR_IN_SZ(_id, _len, ...) \
c66db311	223	UVERBS_ATTR(_id, UVERBS_ATTR_TYPE_PTR_IN, ptr, _len, ##__VA_ARGS__)
35410306 MB	224	/* If sizeof(_type) <= sizeof(u64), this will be inlined rather than a pointer */
35410306 MB	225	#define UVERBS_ATTR_PTR_IN(_id, _type, ...) \
c66db311	226	UVERBS_ATTR_PTR_IN_SZ(_id, _type, ##__VA_ARGS__)
35410306	227	#define UVERBS_ATTR_PTR_OUT_SZ(_id, _len, ...) \
c66db311	228	UVERBS_ATTR(_id, UVERBS_ATTR_TYPE_PTR_OUT, ptr, _len, ##__VA_ARGS__)
35410306	229	#define UVERBS_ATTR_PTR_OUT(_id, _type, ...) \
c66db311	230	UVERBS_ATTR_PTR_OUT_SZ(_id, _type, ##__VA_ARGS__)
494c5580 MB	231	#define UVERBS_ATTR_ENUM_IN(_id, _enum_arr, ...) \
	232	UVERBS_ATTR(_id, UVERBS_ATTR_TYPE_ENUM_IN, enum_def, \
	233	.ids = (_enum_arr), \
	234	.num_elems = ARRAY_SIZE(_enum_arr), ##__VA_ARGS__)
35410306 MB	235
	236	/*
	237	* In new compiler, UVERBS_ATTR_IDR (and FD) could be simplified by declaring
	238	* it as
	239	* {.id = _id, \
	240	* .attr {.type = __obj_class, \
	241	* .obj = {.obj_type = _idr_type, \
	242	* .access = _access \
	243	* }, ##__VA_ARGS__ } }
	244	* But since we support older compilers too, we need the more complex code.
	245	*/
	246	#define ___UVERBS_ATTR_OBJ0(_id, _obj_class, _obj_type, _access, ...)\
	247	((const struct uverbs_attr_def) \
	248	{.id = _id, \
1f07e08f MB	249	.attr = { {.obj = {.type = _obj_class, .obj_type = _obj_type, \
1f07e08f MB	250	.access = _access, .flags = 0 } }, } })
35410306 MB	251	#define ___UVERBS_ATTR_OBJ1(_id, _obj_class, _obj_type, _access, _flags)\
	252	((const struct uverbs_attr_def) \
	253	{.id = _id, \
1f07e08f MB	254	.attr = { {.obj = {.type = _obj_class, .obj_type = _obj_type, \
1f07e08f MB	255	.access = _access, _flags} }, } })
35410306 MB	256	#define ___UVERBS_ATTR_OBJ(_id, _obj_class, _obj_type, _access, _flags, \
	257	_n, ...) \
	258	___UVERBS_ATTR_OBJ##_n(_id, _obj_class, _obj_type, _access, _flags)
	259	#define __UVERBS_ATTR_OBJ(_id, _obj_class, _obj_type, _access, ...) \
	260	___UVERBS_ATTR_OBJ(_id, _obj_class, _obj_type, _access, \
	261	##__VA_ARGS__, 1, 0)
	262	#define UVERBS_ATTR_IDR(_id, _idr_type, _access, ...) \
	263	__UVERBS_ATTR_OBJ(_id, UVERBS_ATTR_TYPE_IDR, _idr_type, _access,\
	264	##__VA_ARGS__)
	265	#define UVERBS_ATTR_FD(_id, _fd_type, _access, ...) \
	266	__UVERBS_ATTR_OBJ(_id, UVERBS_ATTR_TYPE_FD, _fd_type, \
	267	(_access) + BUILD_BUG_ON_ZERO( \
	268	(_access) != UVERBS_ACCESS_NEW && \
	269	(_access) != UVERBS_ACCESS_READ), \
	270	##__VA_ARGS__)
	271	#define DECLARE_UVERBS_ATTR_SPEC(_name, ...) \
	272	const struct uverbs_attr_def _name = __VA_ARGS__
	273
494c5580 MB	274	#define DECLARE_UVERBS_ENUM(_name, ...) \
	275	const struct uverbs_enum_spec _name = { \
	276	.len = ARRAY_SIZE(((struct uverbs_attr_spec[]){__VA_ARGS__})),\
	277	.ids = {__VA_ARGS__}, \
	278	}
35410306 MB	279	#define _UVERBS_METHOD_ATTRS_SZ(...) \
	280	(sizeof((const struct uverbs_attr_def * const []){__VA_ARGS__}) /\
	281	sizeof(const struct uverbs_attr_def *))
	282	#define _UVERBS_METHOD(_id, _handler, _flags, ...) \
	283	((const struct uverbs_method_def) { \
	284	.id = _id, \
	285	.flags = _flags, \
	286	.handler = _handler, \
	287	.num_attrs = _UVERBS_METHOD_ATTRS_SZ(__VA_ARGS__), \
	288	.attrs = &(const struct uverbs_attr_def * const []){__VA_ARGS__} })
	289	#define DECLARE_UVERBS_METHOD(_name, _id, _handler, ...) \
	290	const struct uverbs_method_def _name = \
	291	_UVERBS_METHOD(_id, _handler, 0, ##__VA_ARGS__)
	292	#define DECLARE_UVERBS_CTX_METHOD(_name, _id, _handler, _flags, ...) \
	293	const struct uverbs_method_def _name = \
	294	_UVERBS_METHOD(_id, _handler, \
	295	UVERBS_ACTION_FLAG_CREATE_ROOT, \
	296	##__VA_ARGS__)
	297	#define _UVERBS_OBJECT_METHODS_SZ(...) \
	298	(sizeof((const struct uverbs_method_def * const []){__VA_ARGS__}) / \
	299	sizeof(const struct uverbs_method_def *))
5009010f MB	300	#define _UVERBS_OBJECT(_id, _type_attrs, ...) \
5009010f MB	301	((const struct uverbs_object_def) { \
09e3ebf8	302	.id = _id, \
35410306 MB	303	.type_attrs = _type_attrs, \
	304	.num_methods = _UVERBS_OBJECT_METHODS_SZ(__VA_ARGS__), \
	305	.methods = &(const struct uverbs_method_def * const []){__VA_ARGS__} })
5009010f MB	306	#define DECLARE_UVERBS_OBJECT(_name, _id, _type_attrs, ...) \
	307	const struct uverbs_object_def _name = \
	308	_UVERBS_OBJECT(_id, _type_attrs, ##__VA_ARGS__)
09e3ebf8 MB	309	#define _UVERBS_TREE_OBJECTS_SZ(...) \
	310	(sizeof((const struct uverbs_object_def * const []){__VA_ARGS__}) / \
	311	sizeof(const struct uverbs_object_def *))
	312	#define _UVERBS_OBJECT_TREE(...) \
	313	((const struct uverbs_object_tree_def) { \
	314	.num_objects = _UVERBS_TREE_OBJECTS_SZ(__VA_ARGS__), \
	315	.objects = &(const struct uverbs_object_def * const []){__VA_ARGS__} })
	316	#define DECLARE_UVERBS_OBJECT_TREE(_name, ...) \
	317	const struct uverbs_object_tree_def _name = \
	318	_UVERBS_OBJECT_TREE(__VA_ARGS__)
	319
fac9658c MB	320	/* =================================================
	321	* Parsing infrastructure
	322	* =================================================
	323	*/
	324
	325	struct uverbs_ptr_attr {
2f36028c	326	u64 data;
fac9658c MB	327	u16 len;
	328	/* Combination of bits from enum UVERBS_ATTR_F_XXXX */
	329	u16 flags;
494c5580	330	u8 enum_id;
fac9658c MB	331	};
fac9658c MB	332
f43dbebf	333	struct uverbs_obj_attr {
fac9658c MB	334	/* pointer to the kernel descriptor -> type, access, etc */
fac9658c MB	335	const struct uverbs_obj_type *type;
f43dbebf	336	struct ib_uobject *uobject;
fac9658c MB	337	/* fd or id in idr of this object */
fac9658c MB	338	int id;
f43dbebf MB	339	};
	340
	341	struct uverbs_attr {
fac9658c MB	342	/*
	343	* pointer to the user-space given attribute, in order to write the
	344	* new uobject's id or update flags.
	345	*/
	346	struct ib_uverbs_attr __user *uattr;
	347	union {
	348	struct uverbs_ptr_attr ptr_attr;
	349	struct uverbs_obj_attr obj_attr;
	350	};
f43dbebf MB	351	};
	352
	353	struct uverbs_attr_bundle_hash {
	354	/* if bit i is set, it means attrs[i] contains valid information */
	355	unsigned long *valid_bitmap;
	356	size_t num_attrs;
	357	/*
	358	* arrays of attributes, each element corresponds to the specification
	359	* of the attribute in the same index.
	360	*/
	361	struct uverbs_attr *attrs;
	362	};
	363
	364	struct uverbs_attr_bundle {
	365	size_t num_buckets;
	366	struct uverbs_attr_bundle_hash hash[];
	367	};
	368
	369	static inline bool uverbs_attr_is_valid_in_hash(const struct uverbs_attr_bundle_hash *attrs_hash,
	370	unsigned int idx)
	371	{
	372	return test_bit(idx, attrs_hash->valid_bitmap);
	373	}
	374
35410306 MB	375	static inline bool uverbs_attr_is_valid(const struct uverbs_attr_bundle *attrs_bundle,
	376	unsigned int idx)
	377	{
	378	u16 idx_bucket = idx >> UVERBS_ID_NS_SHIFT;
	379
	380	if (attrs_bundle->num_buckets <= idx_bucket)
	381	return false;
	382
	383	return uverbs_attr_is_valid_in_hash(&attrs_bundle->hash[idx_bucket],
	384	idx & ~UVERBS_ID_NS_MASK);
	385	}
	386
41b2a71f MB	387	#define IS_UVERBS_COPY_ERR(_ret) ((_ret) && (_ret) != -ENOENT)
41b2a71f MB	388
d70724f1 MB	389	static inline const struct uverbs_attr uverbs_attr_get(const struct uverbs_attr_bundle attrs_bundle,
	390	u16 idx)
	391	{
	392	u16 idx_bucket = idx >> UVERBS_ID_NS_SHIFT;
	393
	394	if (!uverbs_attr_is_valid(attrs_bundle, idx))
	395	return ERR_PTR(-ENOENT);
	396
	397	return &attrs_bundle->hash[idx_bucket].attrs[idx & ~UVERBS_ID_NS_MASK];
	398	}
	399
494c5580 MB	400	static inline int uverbs_attr_get_enum_id(const struct uverbs_attr_bundle *attrs_bundle,
	401	u16 idx)
	402	{
	403	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
	404
	405	if (IS_ERR(attr))
	406	return PTR_ERR(attr);
	407
	408	return attr->ptr_attr.enum_id;
	409	}
	410
be934cca AL	411	static inline void uverbs_attr_get_obj(const struct uverbs_attr_bundle attrs_bundle,
	412	u16 idx)
	413	{
	414	struct ib_uobject *uobj =
	415	uverbs_attr_get(attrs_bundle, idx)->obj_attr.uobject;
	416
	417	if (IS_ERR(uobj))
	418	return uobj;
	419
	420	return uobj->object;
	421	}
	422
d70724f1	423	static inline int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle,
89d9e8d3	424	size_t idx, const void *from, size_t size)
d70724f1 MB	425	{
	426	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
	427	u16 flags;
89d9e8d3	428	size_t min_size;
d70724f1 MB	429
	430	if (IS_ERR(attr))
	431	return PTR_ERR(attr);
	432
89d9e8d3	433	min_size = min_t(size_t, attr->ptr_attr.len, size);
2f36028c	434	if (copy_to_user(u64_to_user_ptr(attr->ptr_attr.data), from, min_size))
89d9e8d3 MB	435	return -EFAULT;
89d9e8d3 MB	436
d70724f1	437	flags = attr->ptr_attr.flags \| UVERBS_ATTR_F_VALID_OUTPUT;
89d9e8d3 MB	438	if (put_user(flags, &attr->uattr->flags))
	439	return -EFAULT;
	440
	441	return 0;
d70724f1 MB	442	}
d70724f1 MB	443
89d9e8d3 MB	444	static inline bool uverbs_attr_ptr_is_inline(const struct uverbs_attr *attr)
	445	{
	446	return attr->ptr_attr.len <= sizeof(attr->ptr_attr.data);
	447	}
	448
	449	static inline int _uverbs_copy_from(void *to,
d70724f1	450	const struct uverbs_attr_bundle *attrs_bundle,
89d9e8d3 MB	451	size_t idx,
89d9e8d3 MB	452	size_t size)
d70724f1 MB	453	{
	454	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
	455
	456	if (IS_ERR(attr))
	457	return PTR_ERR(attr);
	458
89d9e8d3 MB	459	/*
89d9e8d3 MB	460	* Validation ensures attr->ptr_attr.len >= size. If the caller is
c66db311 MB	461	* using UVERBS_ATTR_SPEC_F_MIN_SZ_OR_ZERO then it must call
c66db311 MB	462	* uverbs_copy_from_or_zero.
89d9e8d3 MB	463	*/
	464	if (unlikely(size < attr->ptr_attr.len))
	465	return -EINVAL;
	466
	467	if (uverbs_attr_ptr_is_inline(attr))
d70724f1	468	memcpy(to, &attr->ptr_attr.data, attr->ptr_attr.len);
2f36028c JG	469	else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
2f36028c JG	470	attr->ptr_attr.len))
d70724f1 MB	471	return -EFAULT;
	472
	473	return 0;
	474	}
	475
c66db311 MB	476	static inline int _uverbs_copy_from_or_zero(void *to,
	477	const struct uverbs_attr_bundle *attrs_bundle,
	478	size_t idx,
	479	size_t size)
	480	{
	481	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
	482	size_t min_size;
	483
	484	if (IS_ERR(attr))
	485	return PTR_ERR(attr);
	486
	487	min_size = min_t(size_t, size, attr->ptr_attr.len);
	488
	489	if (uverbs_attr_ptr_is_inline(attr))
	490	memcpy(to, &attr->ptr_attr.data, min_size);
	491	else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
	492	min_size))
	493	return -EFAULT;
	494
	495	if (size > min_size)
	496	memset(to + min_size, 0, size - min_size);
	497
	498	return 0;
	499	}
	500
d70724f1	501	#define uverbs_copy_from(to, attrs_bundle, idx) \
89d9e8d3	502	_uverbs_copy_from(to, attrs_bundle, idx, sizeof(*to))
d70724f1	503
c66db311 MB	504	#define uverbs_copy_from_or_zero(to, attrs_bundle, idx) \
	505	_uverbs_copy_from_or_zero(to, attrs_bundle, idx, sizeof(*to))
	506
118620d3 MB	507	/* =================================================
	508	* Definitions -> Specs infrastructure
	509	* =================================================
	510	*/
	511
	512	/*
	513	* uverbs_alloc_spec_tree - Merges different common and driver specific feature
	514	* into one parsing tree that every uverbs command will be parsed upon.
	515	*
	516	* @num_trees: Number of trees in the array @trees.
	517	* @trees: Array of pointers to tree root definitions to merge. Each such tree
	518	* possibly contains objects, methods and attributes definitions.
	519	*
	520	* Returns:
	521	* uverbs_root_spec *: The root of the merged parsing tree.
	522	* On error, we return an error code. Error is checked via IS_ERR.
	523	*
	524	* The following merges could take place:
	525	* a. Two trees representing the same method with different handler
	526	* -> We take the handler of the tree that its handler != NULL
	527	* and its index in the trees array is greater. The incentive for that
	528	* is that developers are expected to first merge common trees and then
	529	* merge trees that gives specialized the behaviour.
	530	* b. Two trees representing the same object with different
	531	* type_attrs (struct uverbs_obj_type):
	532	* -> We take the type_attrs of the tree that its type_attr != NULL
	533	* and its index in the trees array is greater. This could be used
	534	* in order to override the free function, allocation size, etc.
	535	* c. Two trees representing the same method attribute (same id but possibly
	536	* different attributes):
	537	* -> ERROR (-ENOENT), we believe that's not the programmer's intent.
	538	*
	539	* An object without any methods is considered invalid and will abort the
	540	* function with -ENOENT error.
	541	*/
52427112	542	#if IS_ENABLED(CONFIG_INFINIBAND_USER_ACCESS)
118620d3 MB	543	struct uverbs_root_spec *uverbs_alloc_spec_tree(unsigned int num_trees,
	544	const struct uverbs_object_tree_def **trees);
	545	void uverbs_free_spec_tree(struct uverbs_root_spec *root);
52427112 MB	546	#else
	547	static inline struct uverbs_root_spec *uverbs_alloc_spec_tree(unsigned int num_trees,
	548	const struct uverbs_object_tree_def **trees)
	549	{
	550	return NULL;
	551	}
	552
	553	static inline void uverbs_free_spec_tree(struct uverbs_root_spec *root)
	554	{
	555	}
	556	#endif
a0aa309c	557
118620d3	558	#endif