include/rdma/uverbs_ioctl.h - linux-mtk - Git at Google

 /*
  * 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
	/*
	* 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