[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
};

/* Specification of a single attribute inside the ioctl message */
/* good size 16 */
struct uverbs_attr_spec {
	u8 type;

	/*
	 * Support extending attributes by length. Allow the user to provide
	 * more bytes than ptr.len, but check that everything after is zero'd
	 * by the user.
	 */
	u8 zero_trailing:1;
	/*
	 * Valid only for PTR_IN. Allocate and copy the data inside
	 * the parser
	 */
	u8 alloc_and_copy:1;
	u8 mandatory:1;

	union {
		struct {
			/* Current known size to kernel */
			u16 len;
			/* User isn't allowed to provide something < min_len */
			u16 min_len;
		} ptr;

		struct {
			/*
			 * higher bits mean the namespace and lower bits mean
			 * the type id within the namespace.
			 */
			u16 obj_type;
			u8 access;
		} obj;

		struct {
			u8 num_elems;
		} enum_def;
	} u;

	/* This weird split of the enum lets us remove some padding */
	union {
		struct {
			/*
			 * 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;
	} u2;
};

/*
 * Information about the API is loaded into a radix tree. For IOCTL we start
 * with a tuple of:
 *  object_id, attr_id, method_id
 *
 * Which is a 48 bit value, with most of the bits guaranteed to be zero. Based
 * on the current kernel support this is compressed into 16 bit key for the
 * radix tree. Since this compression is entirely internal to the kernel the
 * below limits can be revised if the kernel gains additional data.
 *
 * With 64 leafs per node this is a 3 level radix tree.
 *
 * The tree encodes multiple types, and uses a scheme where OBJ_ID,0,0 returns
 * the object slot, and OBJ_ID,METH_ID,0 and returns the method slot.
 */
enum uapi_radix_data {
	UVERBS_API_NS_FLAG = 1U << UVERBS_ID_NS_SHIFT,

	UVERBS_API_ATTR_KEY_BITS = 6,
	UVERBS_API_ATTR_KEY_MASK = GENMASK(UVERBS_API_ATTR_KEY_BITS - 1, 0),
	UVERBS_API_ATTR_BKEY_LEN = (1 << UVERBS_API_ATTR_KEY_BITS) - 1,

	UVERBS_API_METHOD_KEY_BITS = 5,
	UVERBS_API_METHOD_KEY_SHIFT = UVERBS_API_ATTR_KEY_BITS,
	UVERBS_API_METHOD_KEY_NUM_CORE = 24,
	UVERBS_API_METHOD_KEY_NUM_DRIVER = (1 << UVERBS_API_METHOD_KEY_BITS) -
					   UVERBS_API_METHOD_KEY_NUM_CORE,
	UVERBS_API_METHOD_KEY_MASK = GENMASK(
		UVERBS_API_METHOD_KEY_BITS + UVERBS_API_METHOD_KEY_SHIFT - 1,
		UVERBS_API_METHOD_KEY_SHIFT),

	UVERBS_API_OBJ_KEY_BITS = 5,
	UVERBS_API_OBJ_KEY_SHIFT =
		UVERBS_API_METHOD_KEY_BITS + UVERBS_API_METHOD_KEY_SHIFT,
	UVERBS_API_OBJ_KEY_NUM_CORE = 24,
	UVERBS_API_OBJ_KEY_NUM_DRIVER =
		(1 << UVERBS_API_OBJ_KEY_BITS) - UVERBS_API_OBJ_KEY_NUM_CORE,
	UVERBS_API_OBJ_KEY_MASK = GENMASK(31, UVERBS_API_OBJ_KEY_SHIFT),

	/* This id guaranteed to not exist in the radix tree */
	UVERBS_API_KEY_ERR = 0xFFFFFFFF,
};

static inline __attribute_const__ u32 uapi_key_obj(u32 id)
{
	if (id & UVERBS_API_NS_FLAG) {
		id &= ~UVERBS_API_NS_FLAG;
		if (id >= UVERBS_API_OBJ_KEY_NUM_DRIVER)
			return UVERBS_API_KEY_ERR;
		id = id + UVERBS_API_OBJ_KEY_NUM_CORE;
	} else {
		if (id >= UVERBS_API_OBJ_KEY_NUM_CORE)
			return UVERBS_API_KEY_ERR;
	}

	return id << UVERBS_API_OBJ_KEY_SHIFT;
}

static inline __attribute_const__ bool uapi_key_is_object(u32 key)
{
	return (key & ~UVERBS_API_OBJ_KEY_MASK) == 0;
}

static inline __attribute_const__ u32 uapi_key_ioctl_method(u32 id)
{
	if (id & UVERBS_API_NS_FLAG) {
		id &= ~UVERBS_API_NS_FLAG;
		if (id >= UVERBS_API_METHOD_KEY_NUM_DRIVER)
			return UVERBS_API_KEY_ERR;
		id = id + UVERBS_API_METHOD_KEY_NUM_CORE;
	} else {
		id++;
		if (id >= UVERBS_API_METHOD_KEY_NUM_CORE)
			return UVERBS_API_KEY_ERR;
	}

	return id << UVERBS_API_METHOD_KEY_SHIFT;
}

static inline __attribute_const__ u32 uapi_key_attr_to_method(u32 attr_key)
{
	return attr_key &
	       (UVERBS_API_OBJ_KEY_MASK | UVERBS_API_METHOD_KEY_MASK);
}

static inline __attribute_const__ bool uapi_key_is_ioctl_method(u32 key)
{
	return (key & UVERBS_API_METHOD_KEY_MASK) != 0 &&
	       (key & UVERBS_API_ATTR_KEY_MASK) == 0;
}

static inline __attribute_const__ u32 uapi_key_attrs_start(u32 ioctl_method_key)
{
	/* 0 is the method slot itself */
	return ioctl_method_key + 1;
}

static inline __attribute_const__ u32 uapi_key_attr(u32 id)
{
	/*
	 * The attr is designed to fit in the typical single radix tree node
	 * of 64 entries. Since allmost all methods have driver attributes we
	 * organize things so that the driver and core attributes interleave to
	 * reduce the length of the attributes array in typical cases.
	 */
	if (id & UVERBS_API_NS_FLAG) {
		id &= ~UVERBS_API_NS_FLAG;
		id++;
		if (id >= 1 << (UVERBS_API_ATTR_KEY_BITS - 1))
			return UVERBS_API_KEY_ERR;
		id = (id << 1) | 0;
	} else {
		if (id >= 1 << (UVERBS_API_ATTR_KEY_BITS - 1))
			return UVERBS_API_KEY_ERR;
		id = (id << 1) | 1;
	}

	return id;
}

static inline __attribute_const__ bool uapi_key_is_attr(u32 key)
{
	return (key & UVERBS_API_METHOD_KEY_MASK) != 0 &&
	       (key & UVERBS_API_ATTR_KEY_MASK) != 0;
}

/*
 * This returns a value in the range [0 to UVERBS_API_ATTR_BKEY_LEN),
 * basically it undoes the reservation of 0 in the ID numbering. attr_key
 * must already be masked with UVERBS_API_ATTR_KEY_MASK, or be the output of
 * uapi_key_attr().
 */
static inline __attribute_const__ u32 uapi_bkey_attr(u32 attr_key)
{
	return attr_key - 1;
}

/*
 * =======================================
 *	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_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)[];
};

/*
 * =======================================
 *	Attribute Specifications
 * =======================================
 */

#define UVERBS_ATTR_SIZE(_min_len, _len)			\
	.u.ptr.min_len = _min_len, .u.ptr.len = _len

#define UVERBS_ATTR_NO_DATA() UVERBS_ATTR_SIZE(0, 0)

/*
 * Specifies a uapi structure that cannot be extended. The user must always
 * supply the whole structure and nothing more. The structure must be declared
 * in a header under include/uapi/rdma.
 */
#define UVERBS_ATTR_TYPE(_type)					\
	.u.ptr.min_len = sizeof(_type), .u.ptr.len = sizeof(_type)
/*
 * Specifies a uapi structure where the user must provide at least up to
 * member 'last'.  Anything after last and up until the end of the structure
 * can be non-zero, anything longer than the end of the structure must be
 * zero. The structure must be declared in a header under include/uapi/rdma.
 */
#define UVERBS_ATTR_STRUCT(_type, _last)                                       \
	.zero_trailing = 1,                                                    \
	UVERBS_ATTR_SIZE(((uintptr_t)(&((_type *)0)->_last + 1)),              \
			 sizeof(_type))
/*
 * Specifies at least min_len bytes must be passed in, but the amount can be
 * larger, up to the protocol maximum size. No check for zeroing is done.
 */
#define UVERBS_ATTR_MIN_SIZE(_min_len) UVERBS_ATTR_SIZE(_min_len, USHRT_MAX)

/* Must be used in the '...' of any UVERBS_ATTR */
#define UA_ALLOC_AND_COPY .alloc_and_copy = 1
#define UA_MANDATORY .mandatory = 1
#define UA_OPTIONAL .mandatory = 0

#define UVERBS_ATTR_IDR(_attr_id, _idr_type, _access, ...)                     \
	(&(const struct uverbs_attr_def){                                      \
		.id = _attr_id,                                                \
		.attr = { .type = UVERBS_ATTR_TYPE_IDR,                        \
			  .u.obj.obj_type = _idr_type,                         \
			  .u.obj.access = _access,                             \
			  __VA_ARGS__ } })

#define UVERBS_ATTR_FD(_attr_id, _fd_type, _access, ...)                       \
	(&(const struct uverbs_attr_def){                                      \
		.id = (_attr_id) +                                             \
		      BUILD_BUG_ON_ZERO((_access) != UVERBS_ACCESS_NEW &&      \
					(_access) != UVERBS_ACCESS_READ),      \
		.attr = { .type = UVERBS_ATTR_TYPE_FD,                         \
			  .u.obj.obj_type = _fd_type,                          \
			  .u.obj.access = _access,                             \
			  __VA_ARGS__ } })

#define UVERBS_ATTR_PTR_IN(_attr_id, _type, ...)                               \
	(&(const struct uverbs_attr_def){                                      \
		.id = _attr_id,                                                \
		.attr = { .type = UVERBS_ATTR_TYPE_PTR_IN,                     \
			  _type,                                               \
			  __VA_ARGS__ } })

#define UVERBS_ATTR_PTR_OUT(_attr_id, _type, ...)                              \
	(&(const struct uverbs_attr_def){                                      \
		.id = _attr_id,                                                \
		.attr = { .type = UVERBS_ATTR_TYPE_PTR_OUT,                    \
			  _type,                                               \
			  __VA_ARGS__ } })

/* _enum_arry should be a 'static const union uverbs_attr_spec[]' */
#define UVERBS_ATTR_ENUM_IN(_attr_id, _enum_arr, ...)                          \
	(&(const struct uverbs_attr_def){                                      \
		.id = _attr_id,                                                \
		.attr = { .type = UVERBS_ATTR_TYPE_ENUM_IN,                    \
			  .u2.enum_def.ids = _enum_arr,                        \
			  .u.enum_def.num_elems = ARRAY_SIZE(_enum_arr),       \
			  __VA_ARGS__ },                                       \
	})

/*
 * An input value that is a bitwise combination of values of _enum_type.
 * This permits the flag value to be passed as either a u32 or u64, it must
 * be retrieved via uverbs_get_flag().
 */
#define UVERBS_ATTR_FLAGS_IN(_attr_id, _enum_type, ...)                        \
	UVERBS_ATTR_PTR_IN(                                                    \
		_attr_id,                                                      \
		UVERBS_ATTR_SIZE(sizeof(u32) + BUILD_BUG_ON_ZERO(              \
						       !sizeof(_enum_type *)), \
				 sizeof(u64)),                                 \
		__VA_ARGS__)

/*
 * This spec is used in order to pass information to the hardware driver in a
 * legacy way. Every verb that could get driver specific data should get this
 * spec.
 */
#define UVERBS_ATTR_UHW()                                                      \
	UVERBS_ATTR_PTR_IN(UVERBS_ATTR_UHW_IN,                                 \
			   UVERBS_ATTR_MIN_SIZE(0),			       \
			   UA_OPTIONAL),				       \
	UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_UHW_OUT,                               \
			    UVERBS_ATTR_MIN_SIZE(0),			       \
			    UA_OPTIONAL)

/*
 * =======================================
 *	Declaration helpers
 * =======================================
 */

#define DECLARE_UVERBS_OBJECT_TREE(_name, ...)                                 \
	static const struct uverbs_object_def *const _name##_ptr[] = {         \
		__VA_ARGS__,                                                   \
	};                                                                     \
	static const struct uverbs_object_tree_def _name = {                   \
		.num_objects = ARRAY_SIZE(_name##_ptr),                        \
		.objects = &_name##_ptr,                                       \
	}

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


struct uverbs_ptr_attr {
	/*
	 * If UVERBS_ATTR_SPEC_F_ALLOC_AND_COPY is set then the 'ptr' is
	 * used.
	 */
	union {
		void *ptr;
		u64 data;
	};
	u16		len;
	u16		uattr_idx;
	u8		enum_id;
};

struct uverbs_obj_attr {
	struct ib_uobject		*uobject;
	const struct uverbs_api_attr	*attr_elm;
};

struct uverbs_attr {
	union {
		struct uverbs_ptr_attr	ptr_attr;
		struct uverbs_obj_attr	obj_attr;
	};
};

struct uverbs_attr_bundle {
	struct ib_uverbs_file *ufile;
	DECLARE_BITMAP(attr_present, UVERBS_API_ATTR_BKEY_LEN);
	struct uverbs_attr attrs[];
};

static inline bool uverbs_attr_is_valid(const struct uverbs_attr_bundle *attrs_bundle,
					unsigned int idx)
{
	return test_bit(uapi_bkey_attr(uapi_key_attr(idx)),
			attrs_bundle->attr_present);
}

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

	return &attrs_bundle->attrs[uapi_bkey_attr(uapi_key_attr(idx))];
}

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)
{
	const struct uverbs_attr *attr;

	attr = uverbs_attr_get(attrs_bundle, idx);
	if (IS_ERR(attr))
		return ERR_CAST(attr);

	return attr->obj_attr.uobject->object;
}

static inline struct ib_uobject *uverbs_attr_get_uobject(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 ERR_CAST(attr);

	return attr->obj_attr.uobject;
}

static inline int
uverbs_attr_get_len(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.len;
}

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 void *uverbs_attr_get_alloced_ptr(
	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 (void *)attr;

	return uverbs_attr_ptr_is_inline(attr) ? (void *)&attr->ptr_attr.data :
						 attr->ptr_attr.ptr;
}

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))

#if IS_ENABLED(CONFIG_INFINIBAND_USER_ACCESS)
int uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle,
		       size_t idx, u64 allowed_bits);
int uverbs_get_flags32(u32 *to, const struct uverbs_attr_bundle *attrs_bundle,
		       size_t idx, u64 allowed_bits);
int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle, size_t idx,
		   const void *from, size_t size);
__malloc void *_uverbs_alloc(struct uverbs_attr_bundle *bundle, size_t size,
			     gfp_t flags);

static inline __malloc void *uverbs_alloc(struct uverbs_attr_bundle *bundle,
					  size_t size)
{
	return _uverbs_alloc(bundle, size, GFP_KERNEL);
}

static inline __malloc void *uverbs_zalloc(struct uverbs_attr_bundle *bundle,
					   size_t size)
{
	return _uverbs_alloc(bundle, size, GFP_KERNEL | __GFP_ZERO);
}
#else
static inline int
uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle,
		   size_t idx, u64 allowed_bits)
{
	return -EINVAL;
}
static inline int
uverbs_get_flags32(u32 *to, const struct uverbs_attr_bundle *attrs_bundle,
		   size_t idx, u64 allowed_bits)
{
	return -EINVAL;
}
static inline int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle,
				 size_t idx, const void *from, size_t size)
{
	return -EINVAL;
}
static inline __malloc void *uverbs_alloc(struct uverbs_attr_bundle *bundle,
					  size_t size)
{
	return ERR_PTR(-EINVAL);
}
static inline __malloc void *uverbs_zalloc(struct uverbs_attr_bundle *bundle,
					   size_t size)
{
	return ERR_PTR(-EINVAL);
}
#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
1f07e08f	64	/* Specification of a single attribute inside the ioctl message */
83bb4442	65	/* good size 16 */
f43dbebf	66	struct uverbs_attr_spec {
d108dac0	67	u8 type;
83bb4442 JG	68
83bb4442 JG	69	/*
422e3d37 JG	70	* Support extending attributes by length. Allow the user to provide
	71	* more bytes than ptr.len, but check that everything after is zero'd
	72	* by the user.
83bb4442	73	*/
422e3d37	74	u8 zero_trailing:1;
83bb4442 JG	75	/*
	76	* Valid only for PTR_IN. Allocate and copy the data inside
	77	* the parser
	78	*/
	79	u8 alloc_and_copy:1;
	80	u8 mandatory:1;
d108dac0	81
fac9658c	82	union {
1f07e08f	83	struct {
c66db311	84	/* Current known size to kernel */
d108dac0	85	u16 len;
c66db311	86	/* User isn't allowed to provide something < min_len */
d108dac0	87	u16 min_len;
1f07e08f	88	} ptr;
d108dac0	89
1f07e08f	90	struct {
fac9658c MB	91	/*
	92	* higher bits mean the namespace and lower bits mean
	93	* the type id within the namespace.
	94	*/
d108dac0 JG	95	u16 obj_type;
d108dac0 JG	96	u8 access;
fac9658c	97	} obj;
d108dac0 JG	98
	99	struct {
	100	u8 num_elems;
	101	} enum_def;
	102	} u;
	103
	104	/* This weird split of the enum lets us remove some padding */
	105	union {
494c5580	106	struct {
494c5580 MB	107	/*
	108	* The enum attribute can select one of the attributes
	109	* contained in the ids array. Currently only PTR_IN
	110	* attributes are supported in the ids array.
	111	*/
d108dac0	112	const struct uverbs_attr_spec *ids;
494c5580	113	} enum_def;
d108dac0	114	} u2;
f43dbebf MB	115	};
f43dbebf MB	116
9ed3e5f4 JG	117	/*
	118	* Information about the API is loaded into a radix tree. For IOCTL we start
	119	* with a tuple of:
	120	* object_id, attr_id, method_id
	121	*
	122	* Which is a 48 bit value, with most of the bits guaranteed to be zero. Based
	123	* on the current kernel support this is compressed into 16 bit key for the
	124	* radix tree. Since this compression is entirely internal to the kernel the
	125	* below limits can be revised if the kernel gains additional data.
	126	*
	127	* With 64 leafs per node this is a 3 level radix tree.
	128	*
	129	* The tree encodes multiple types, and uses a scheme where OBJ_ID,0,0 returns
	130	* the object slot, and OBJ_ID,METH_ID,0 and returns the method slot.
	131	*/
	132	enum uapi_radix_data {
	133	UVERBS_API_NS_FLAG = 1U << UVERBS_ID_NS_SHIFT,
	134
	135	UVERBS_API_ATTR_KEY_BITS = 6,
	136	UVERBS_API_ATTR_KEY_MASK = GENMASK(UVERBS_API_ATTR_KEY_BITS - 1, 0),
	137	UVERBS_API_ATTR_BKEY_LEN = (1 << UVERBS_API_ATTR_KEY_BITS) - 1,
	138
	139	UVERBS_API_METHOD_KEY_BITS = 5,
	140	UVERBS_API_METHOD_KEY_SHIFT = UVERBS_API_ATTR_KEY_BITS,
	141	UVERBS_API_METHOD_KEY_NUM_CORE = 24,
	142	UVERBS_API_METHOD_KEY_NUM_DRIVER = (1 << UVERBS_API_METHOD_KEY_BITS) -
	143	UVERBS_API_METHOD_KEY_NUM_CORE,
	144	UVERBS_API_METHOD_KEY_MASK = GENMASK(
	145	UVERBS_API_METHOD_KEY_BITS + UVERBS_API_METHOD_KEY_SHIFT - 1,
	146	UVERBS_API_METHOD_KEY_SHIFT),
	147
	148	UVERBS_API_OBJ_KEY_BITS = 5,
	149	UVERBS_API_OBJ_KEY_SHIFT =
	150	UVERBS_API_METHOD_KEY_BITS + UVERBS_API_METHOD_KEY_SHIFT,
	151	UVERBS_API_OBJ_KEY_NUM_CORE = 24,
	152	UVERBS_API_OBJ_KEY_NUM_DRIVER =
	153	(1 << UVERBS_API_OBJ_KEY_BITS) - UVERBS_API_OBJ_KEY_NUM_CORE,
	154	UVERBS_API_OBJ_KEY_MASK = GENMASK(31, UVERBS_API_OBJ_KEY_SHIFT),
	155
	156	/* This id guaranteed to not exist in the radix tree */
	157	UVERBS_API_KEY_ERR = 0xFFFFFFFF,
	158	};
	159
	160	static inline __attribute_const__ u32 uapi_key_obj(u32 id)
	161	{
	162	if (id & UVERBS_API_NS_FLAG) {
	163	id &= ~UVERBS_API_NS_FLAG;
	164	if (id >= UVERBS_API_OBJ_KEY_NUM_DRIVER)
	165	return UVERBS_API_KEY_ERR;
	166	id = id + UVERBS_API_OBJ_KEY_NUM_CORE;
	167	} else {
	168	if (id >= UVERBS_API_OBJ_KEY_NUM_CORE)
	169	return UVERBS_API_KEY_ERR;
	170	}
	171
	172	return id << UVERBS_API_OBJ_KEY_SHIFT;
	173	}
	174
	175	static inline __attribute_const__ bool uapi_key_is_object(u32 key)
	176	{
	177	return (key & ~UVERBS_API_OBJ_KEY_MASK) == 0;
	178	}
	179
	180	static inline __attribute_const__ u32 uapi_key_ioctl_method(u32 id)
181	{
182	if (id & UVERBS_API_NS_FLAG) {
183	id &= ~UVERBS_API_NS_FLAG;
184	if (id >= UVERBS_API_METHOD_KEY_NUM_DRIVER)
185	return UVERBS_API_KEY_ERR;
186	id = id + UVERBS_API_METHOD_KEY_NUM_CORE;
187	} else {
188	id++;
189	if (id >= UVERBS_API_METHOD_KEY_NUM_CORE)
190	return UVERBS_API_KEY_ERR;
191	}
192
193	return id << UVERBS_API_METHOD_KEY_SHIFT;
194	}
195
196	static inline __attribute_const__ u32 uapi_key_attr_to_method(u32 attr_key)
197	{
198	return attr_key &
199	(UVERBS_API_OBJ_KEY_MASK \| UVERBS_API_METHOD_KEY_MASK);
200	}
201
202	static inline __attribute_const__ bool uapi_key_is_ioctl_method(u32 key)
203	{
204	return (key & UVERBS_API_METHOD_KEY_MASK) != 0 &&
205	(key & UVERBS_API_ATTR_KEY_MASK) == 0;
206	}
207
208	static inline __attribute_const__ u32 uapi_key_attrs_start(u32 ioctl_method_key)
209	{
210	/* 0 is the method slot itself */
211	return ioctl_method_key + 1;
212	}
213
214	static inline __attribute_const__ u32 uapi_key_attr(u32 id)
215	{
216	/*
217	* The attr is designed to fit in the typical single radix tree node
218	* of 64 entries. Since allmost all methods have driver attributes we
219	* organize things so that the driver and core attributes interleave to
220	* reduce the length of the attributes array in typical cases.
221	*/
222	if (id & UVERBS_API_NS_FLAG) {
223	id &= ~UVERBS_API_NS_FLAG;
224	id++;
225	if (id >= 1 << (UVERBS_API_ATTR_KEY_BITS - 1))
226	return UVERBS_API_KEY_ERR;
227	id = (id << 1) \| 0;
228	} else {
229	if (id >= 1 << (UVERBS_API_ATTR_KEY_BITS - 1))
230	return UVERBS_API_KEY_ERR;
231	id = (id << 1) \| 1;
232	}
233
234	return id;
235	}
236
237	static inline __attribute_const__ bool uapi_key_is_attr(u32 key)
238	{
239	return (key & UVERBS_API_METHOD_KEY_MASK) != 0 &&
240	(key & UVERBS_API_ATTR_KEY_MASK) != 0;
241	}
242
243	/*
244	* This returns a value in the range [0 to UVERBS_API_ATTR_BKEY_LEN),
245	* basically it undoes the reservation of 0 in the ID numbering. attr_key
246	* must already be masked with UVERBS_API_ATTR_KEY_MASK, or be the output of
247	* uapi_key_attr().
248	*/
249	static inline __attribute_const__ u32 uapi_bkey_attr(u32 attr_key)
250	{
251	return attr_key - 1;
252	}
253
5009010f MB	254	/*
	255	* =======================================
	256	* Verbs definitions
	257	* =======================================
	258	*/
	259
09e3ebf8 MB	260	struct uverbs_attr_def {
	261	u16 id;
	262	struct uverbs_attr_spec attr;
	263	};
	264
	265	struct uverbs_method_def {
	266	u16 id;
	267	/* Combination of bits from enum UVERBS_ACTION_FLAG_XXXX */
	268	u32 flags;
	269	size_t num_attrs;
	270	const struct uverbs_attr_def * const (*attrs)[];
e83f0ecd	271	int (handler)(struct ib_uverbs_file ufile,
09e3ebf8 MB	272	struct uverbs_attr_bundle *ctx);
	273	};
	274
5009010f	275	struct uverbs_object_def {
09e3ebf8	276	u16 id;
5009010f	277	const struct uverbs_obj_type *type_attrs;
09e3ebf8 MB	278	size_t num_methods;
	279	const struct uverbs_method_def * const (*methods)[];
	280	};
	281
	282	struct uverbs_object_tree_def {
	283	size_t num_objects;
	284	const struct uverbs_object_def * const (*objects)[];
5009010f MB	285	};
5009010f MB	286
d108dac0 JG	287	/*
	288	* =======================================
	289	* Attribute Specifications
	290	* =======================================
	291	*/
c66db311	292
c66db311	293	#define UVERBS_ATTR_SIZE(_min_len, _len) \
d108dac0	294	.u.ptr.min_len = _min_len, .u.ptr.len = _len
422e3d37	295
fd44e385 YH	296	#define UVERBS_ATTR_NO_DATA() UVERBS_ATTR_SIZE(0, 0)
fd44e385 YH	297
422e3d37 JG	298	/*
	299	* Specifies a uapi structure that cannot be extended. The user must always
	300	* supply the whole structure and nothing more. The structure must be declared
	301	* in a header under include/uapi/rdma.
	302	*/
	303	#define UVERBS_ATTR_TYPE(_type) \
	304	.u.ptr.min_len = sizeof(_type), .u.ptr.len = sizeof(_type)
	305	/*
	306	* Specifies a uapi structure where the user must provide at least up to
	307	* member 'last'. Anything after last and up until the end of the structure
	308	* can be non-zero, anything longer than the end of the structure must be
	309	* zero. The structure must be declared in a header under include/uapi/rdma.
	310	*/
	311	#define UVERBS_ATTR_STRUCT(_type, _last) \
	312	.zero_trailing = 1, \
	313	UVERBS_ATTR_SIZE(((uintptr_t)(&((_type *)0)->_last + 1)), \
	314	sizeof(_type))
540cd692 JG	315	/*
	316	* Specifies at least min_len bytes must be passed in, but the amount can be
	317	* larger, up to the protocol maximum size. No check for zeroing is done.
	318	*/
	319	#define UVERBS_ATTR_MIN_SIZE(_min_len) UVERBS_ATTR_SIZE(_min_len, USHRT_MAX)
c66db311	320
d108dac0	321	/* Must be used in the '...' of any UVERBS_ATTR */
83bb4442 JG	322	#define UA_ALLOC_AND_COPY .alloc_and_copy = 1
83bb4442 JG	323	#define UA_MANDATORY .mandatory = 1
83bb4442	324	#define UA_OPTIONAL .mandatory = 0
d108dac0 JG	325
d108dac0 JG	326	#define UVERBS_ATTR_IDR(_attr_id, _idr_type, _access, ...) \
9a119cd5	327	(&(const struct uverbs_attr_def){ \
d108dac0 JG	328	.id = _attr_id, \
	329	.attr = { .type = UVERBS_ATTR_TYPE_IDR, \
	330	.u.obj.obj_type = _idr_type, \
	331	.u.obj.access = _access, \
	332	__VA_ARGS__ } })
	333
	334	#define UVERBS_ATTR_FD(_attr_id, _fd_type, _access, ...) \
9a119cd5	335	(&(const struct uverbs_attr_def){ \
d108dac0 JG	336	.id = (_attr_id) + \
	337	BUILD_BUG_ON_ZERO((_access) != UVERBS_ACCESS_NEW && \
	338	(_access) != UVERBS_ACCESS_READ), \
	339	.attr = { .type = UVERBS_ATTR_TYPE_FD, \
	340	.u.obj.obj_type = _fd_type, \
	341	.u.obj.access = _access, \
	342	__VA_ARGS__ } })
	343
	344	#define UVERBS_ATTR_PTR_IN(_attr_id, _type, ...) \
9a119cd5	345	(&(const struct uverbs_attr_def){ \
d108dac0 JG	346	.id = _attr_id, \
	347	.attr = { .type = UVERBS_ATTR_TYPE_PTR_IN, \
	348	_type, \
	349	__VA_ARGS__ } })
	350
	351	#define UVERBS_ATTR_PTR_OUT(_attr_id, _type, ...) \
9a119cd5	352	(&(const struct uverbs_attr_def){ \
d108dac0 JG	353	.id = _attr_id, \
	354	.attr = { .type = UVERBS_ATTR_TYPE_PTR_OUT, \
	355	_type, \
	356	__VA_ARGS__ } })
	357
	358	/* _enum_arry should be a 'static const union uverbs_attr_spec[]' */
	359	#define UVERBS_ATTR_ENUM_IN(_attr_id, _enum_arr, ...) \
9a119cd5	360	(&(const struct uverbs_attr_def){ \
d108dac0 JG	361	.id = _attr_id, \
	362	.attr = { .type = UVERBS_ATTR_TYPE_ENUM_IN, \
	363	.u2.enum_def.ids = _enum_arr, \
	364	.u.enum_def.num_elems = ARRAY_SIZE(_enum_arr), \
	365	__VA_ARGS__ }, \
	366	})
35410306	367
bccd0622 JG	368	/*
	369	* An input value that is a bitwise combination of values of _enum_type.
	370	* This permits the flag value to be passed as either a u32 or u64, it must
	371	* be retrieved via uverbs_get_flag().
	372	*/
	373	#define UVERBS_ATTR_FLAGS_IN(_attr_id, _enum_type, ...) \
	374	UVERBS_ATTR_PTR_IN( \
	375	_attr_id, \
	376	UVERBS_ATTR_SIZE(sizeof(u32) + BUILD_BUG_ON_ZERO( \
	377	!sizeof(_enum_type *)), \
	378	sizeof(u64)), \
	379	__VA_ARGS__)
	380
6c61d2a5 JG	381	/*
	382	* This spec is used in order to pass information to the hardware driver in a
	383	* legacy way. Every verb that could get driver specific data should get this
	384	* spec.
	385	*/
	386	#define UVERBS_ATTR_UHW() \
9a119cd5	387	UVERBS_ATTR_PTR_IN(UVERBS_ATTR_UHW_IN, \
540cd692 JG	388	UVERBS_ATTR_MIN_SIZE(0), \
540cd692 JG	389	UA_OPTIONAL), \
9a119cd5	390	UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_UHW_OUT, \
540cd692 JG	391	UVERBS_ATTR_MIN_SIZE(0), \
540cd692 JG	392	UA_OPTIONAL)
6c61d2a5	393
35410306	394	/*
d108dac0 JG	395	* =======================================
	396	* Declaration helpers
	397	* =======================================
35410306	398	*/
6c61d2a5 JG	399
	400	#define DECLARE_UVERBS_OBJECT_TREE(_name, ...) \
	401	static const struct uverbs_object_def *const _name##_ptr[] = { \
	402	__VA_ARGS__, \
	403	}; \
	404	static const struct uverbs_object_tree_def _name = { \
	405	.num_objects = ARRAY_SIZE(_name##_ptr), \
	406	.objects = &_name##_ptr, \
	407	}
09e3ebf8	408
fac9658c MB	409	/* =================================================
	410	* Parsing infrastructure
	411	* =================================================
	412	*/
	413
3a863577	414
fac9658c	415	struct uverbs_ptr_attr {
8762d149 MB	416	/*
	417	* If UVERBS_ATTR_SPEC_F_ALLOC_AND_COPY is set then the 'ptr' is
	418	* used.
	419	*/
	420	union {
	421	void *ptr;
	422	u64 data;
	423	};
fac9658c	424	u16 len;
6a1f444f	425	u16 uattr_idx;
494c5580	426	u8 enum_id;
fac9658c MB	427	};
fac9658c MB	428
f43dbebf MB	429	struct uverbs_obj_attr {
f43dbebf MB	430	struct ib_uobject *uobject;
3a863577	431	const struct uverbs_api_attr *attr_elm;
f43dbebf MB	432	};
	433
	434	struct uverbs_attr {
fac9658c MB	435	union {
	436	struct uverbs_ptr_attr ptr_attr;
	437	struct uverbs_obj_attr obj_attr;
	438	};
f43dbebf MB	439	};
f43dbebf MB	440
f43dbebf	441	struct uverbs_attr_bundle {
4b3dd2bb	442	struct ib_uverbs_file *ufile;
3a863577 JG	443	DECLARE_BITMAP(attr_present, UVERBS_API_ATTR_BKEY_LEN);
3a863577 JG	444	struct uverbs_attr attrs[];
f43dbebf MB	445	};
f43dbebf MB	446
35410306 MB	447	static inline bool uverbs_attr_is_valid(const struct uverbs_attr_bundle *attrs_bundle,
	448	unsigned int idx)
	449	{
3a863577 JG	450	return test_bit(uapi_bkey_attr(uapi_key_attr(idx)),
3a863577 JG	451	attrs_bundle->attr_present);
35410306 MB	452	}
35410306 MB	453
41b2a71f MB	454	#define IS_UVERBS_COPY_ERR(_ret) ((_ret) && (_ret) != -ENOENT)
41b2a71f MB	455
d70724f1 MB	456	static inline const struct uverbs_attr uverbs_attr_get(const struct uverbs_attr_bundle attrs_bundle,
	457	u16 idx)
	458	{
d70724f1 MB	459	if (!uverbs_attr_is_valid(attrs_bundle, idx))
	460	return ERR_PTR(-ENOENT);
	461
3a863577	462	return &attrs_bundle->attrs[uapi_bkey_attr(uapi_key_attr(idx))];
d70724f1 MB	463	}
d70724f1 MB	464
494c5580 MB	465	static inline int uverbs_attr_get_enum_id(const struct uverbs_attr_bundle *attrs_bundle,
	466	u16 idx)
	467	{
	468	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
	469
	470	if (IS_ERR(attr))
	471	return PTR_ERR(attr);
	472
	473	return attr->ptr_attr.enum_id;
	474	}
	475
be934cca AL	476	static inline void uverbs_attr_get_obj(const struct uverbs_attr_bundle attrs_bundle,
	477	u16 idx)
	478	{
f4602cbb	479	const struct uverbs_attr *attr;
be934cca	480
f4602cbb JG	481	attr = uverbs_attr_get(attrs_bundle, idx);
	482	if (IS_ERR(attr))
	483	return ERR_CAST(attr);
be934cca	484
f4602cbb	485	return attr->obj_attr.uobject->object;
be934cca AL	486	}
be934cca AL	487
3efa3812 MB	488	static inline struct ib_uobject uverbs_attr_get_uobject(const struct uverbs_attr_bundle attrs_bundle,
	489	u16 idx)
	490	{
	491	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
	492
	493	if (IS_ERR(attr))
	494	return ERR_CAST(attr);
	495
	496	return attr->obj_attr.uobject;
	497	}
	498
8762d149 MB	499	static inline int
	500	uverbs_attr_get_len(const struct uverbs_attr_bundle *attrs_bundle, u16 idx)
	501	{
	502	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
	503
	504	if (IS_ERR(attr))
	505	return PTR_ERR(attr);
	506
	507	return attr->ptr_attr.len;
	508	}
	509
89d9e8d3 MB	510	static inline bool uverbs_attr_ptr_is_inline(const struct uverbs_attr *attr)
	511	{
	512	return attr->ptr_attr.len <= sizeof(attr->ptr_attr.data);
	513	}
	514
8762d149 MB	515	static inline void *uverbs_attr_get_alloced_ptr(
	516	const struct uverbs_attr_bundle *attrs_bundle, u16 idx)
	517	{
	518	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
	519
	520	if (IS_ERR(attr))
	521	return (void *)attr;
	522
	523	return uverbs_attr_ptr_is_inline(attr) ? (void *)&attr->ptr_attr.data :
	524	attr->ptr_attr.ptr;
	525	}
	526
89d9e8d3	527	static inline int _uverbs_copy_from(void *to,
d70724f1	528	const struct uverbs_attr_bundle *attrs_bundle,
89d9e8d3 MB	529	size_t idx,
89d9e8d3 MB	530	size_t size)
d70724f1 MB	531	{
	532	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
	533
	534	if (IS_ERR(attr))
	535	return PTR_ERR(attr);
	536
89d9e8d3 MB	537	/*
89d9e8d3 MB	538	* Validation ensures attr->ptr_attr.len >= size. If the caller is
c66db311 MB	539	* using UVERBS_ATTR_SPEC_F_MIN_SZ_OR_ZERO then it must call
c66db311 MB	540	* uverbs_copy_from_or_zero.
89d9e8d3 MB	541	*/
	542	if (unlikely(size < attr->ptr_attr.len))
	543	return -EINVAL;
	544
	545	if (uverbs_attr_ptr_is_inline(attr))
d70724f1	546	memcpy(to, &attr->ptr_attr.data, attr->ptr_attr.len);
2f36028c JG	547	else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
2f36028c JG	548	attr->ptr_attr.len))
d70724f1 MB	549	return -EFAULT;
	550
	551	return 0;
	552	}
	553
c66db311 MB	554	static inline int _uverbs_copy_from_or_zero(void *to,
	555	const struct uverbs_attr_bundle *attrs_bundle,
	556	size_t idx,
	557	size_t size)
	558	{
	559	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
	560	size_t min_size;
	561
	562	if (IS_ERR(attr))
	563	return PTR_ERR(attr);
	564
	565	min_size = min_t(size_t, size, attr->ptr_attr.len);
	566
	567	if (uverbs_attr_ptr_is_inline(attr))
	568	memcpy(to, &attr->ptr_attr.data, min_size);
	569	else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
	570	min_size))
	571	return -EFAULT;
	572
	573	if (size > min_size)
	574	memset(to + min_size, 0, size - min_size);
	575
	576	return 0;
	577	}
	578
d70724f1	579	#define uverbs_copy_from(to, attrs_bundle, idx) \
89d9e8d3	580	_uverbs_copy_from(to, attrs_bundle, idx, sizeof(*to))
d70724f1	581
c66db311 MB	582	#define uverbs_copy_from_or_zero(to, attrs_bundle, idx) \
	583	_uverbs_copy_from_or_zero(to, attrs_bundle, idx, sizeof(*to))
	584
bccd0622 JG	585	#if IS_ENABLED(CONFIG_INFINIBAND_USER_ACCESS)
	586	int uverbs_get_flags64(u64 to, const struct uverbs_attr_bundle attrs_bundle,
	587	size_t idx, u64 allowed_bits);
	588	int uverbs_get_flags32(u32 to, const struct uverbs_attr_bundle attrs_bundle,
	589	size_t idx, u64 allowed_bits);
6a1f444f JG	590	int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle, size_t idx,
6a1f444f JG	591	const void *from, size_t size);
461bb2ee JG	592	__malloc void _uverbs_alloc(struct uverbs_attr_bundle bundle, size_t size,
	593	gfp_t flags);
	594
	595	static inline __malloc void uverbs_alloc(struct uverbs_attr_bundle bundle,
	596	size_t size)
	597	{
	598	return _uverbs_alloc(bundle, size, GFP_KERNEL);
	599	}
	600
	601	static inline __malloc void uverbs_zalloc(struct uverbs_attr_bundle bundle,
	602	size_t size)
	603	{
	604	return _uverbs_alloc(bundle, size, GFP_KERNEL \| __GFP_ZERO);
	605	}
bccd0622 JG	606	#else
	607	static inline int
	608	uverbs_get_flags64(u64 to, const struct uverbs_attr_bundle attrs_bundle,
	609	size_t idx, u64 allowed_bits)
	610	{
	611	return -EINVAL;
	612	}
	613	static inline int
	614	uverbs_get_flags32(u32 to, const struct uverbs_attr_bundle attrs_bundle,
	615	size_t idx, u64 allowed_bits)
	616	{
	617	return -EINVAL;
	618	}
6a1f444f JG	619	static inline int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle,
	620	size_t idx, const void *from, size_t size)
	621	{
	622	return -EINVAL;
	623	}
461bb2ee JG	624	static inline __malloc void uverbs_alloc(struct uverbs_attr_bundle bundle,
	625	size_t size)
	626	{
	627	return ERR_PTR(-EINVAL);
	628	}
	629	static inline __malloc void uverbs_zalloc(struct uverbs_attr_bundle bundle,
	630	size_t size)
	631	{
	632	return ERR_PTR(-EINVAL);
	633	}
bccd0622 JG	634	#endif
bccd0622 JG	635
118620d3	636	#endif