uverbs_ioctl.h 14.3 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438
/*
 * 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>

/*
 * =======================================
 *	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,
};

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 */
	UVERBS_ATTR_SPEC_F_MIN_SZ	= 1U << 1,
};

struct uverbs_attr_spec {
	enum uverbs_attr_type		type;
	union {
		u16				len;
		struct {
			/*
			 * higher bits mean the namespace and lower bits mean
			 * the type id within the namespace.
			 */
			u16			obj_type;
			u8			access;
		} obj;
	};
	/* Combination of bits from enum UVERBS_ATTR_SPEC_F_XXXX */
	u8				flags;
};

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, _len, _type, ...)                           \
	((const struct uverbs_attr_def)				  \
	 {.id = _id, .attr = {.type = _type, {.len = _len}, .flags = 0, } })
#define __UVERBS_ATTR1(_id, _len, _type, _flags)                        \
	((const struct uverbs_attr_def)				  \
	 {.id = _id, .attr = {.type = _type, {.len = _len}, _flags, } })
#define __UVERBS_ATTR(_id, _len, _type, _flags, _n, ...)		\
	__UVERBS_ATTR##_n(_id, _len, _type, _flags)
/*
 * 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, _len, _type, ...)				\
	__UVERBS_ATTR(_id, _len, _type, ##__VA_ARGS__, 1, 0)
#define UVERBS_ATTR_PTR_IN_SZ(_id, _len, ...)				\
	UVERBS_ATTR(_id, _len, UVERBS_ATTR_TYPE_PTR_IN, ##__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, sizeof(_type), ##__VA_ARGS__)
#define UVERBS_ATTR_PTR_OUT_SZ(_id, _len, ...)				\
	UVERBS_ATTR(_id, _len, UVERBS_ATTR_TYPE_PTR_OUT, ##__VA_ARGS__)
#define UVERBS_ATTR_PTR_OUT(_id, _type, ...)				\
	UVERBS_ATTR_PTR_OUT_SZ(_id, sizeof(_type), ##__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 = {.type = _obj_class,					\
		  {.obj = {.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 = {.type = _obj_class,					\
		 {.obj = {.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 _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 {
	union {
		u64		data;
		void	__user *ptr;
	};
	u16		len;
	/* Combination of bits from enum UVERBS_ATTR_F_XXXX */
	u16		flags;
};

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);
}

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_copy_to(const struct uverbs_attr_bundle *attrs_bundle,
				 size_t idx, const void *from)
{
	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
	u16 flags;

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

	flags = attr->ptr_attr.flags | UVERBS_ATTR_F_VALID_OUTPUT;
	return (!copy_to_user(attr->ptr_attr.ptr, from, attr->ptr_attr.len) &&
		!put_user(flags, &attr->uattr->flags)) ? 0 : -EFAULT;
}

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

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

	if (to_size <= sizeof(((struct ib_uverbs_attr *)0)->data))
		memcpy(to, &attr->ptr_attr.data, attr->ptr_attr.len);
	else if (copy_from_user(to, attr->ptr_attr.ptr, attr->ptr_attr.len))
		return -EFAULT;

	return 0;
}

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

/* =================================================
 *	 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