xref: /openbmc/linux/include/rdma/uverbs_ioctl.h (revision 61c581a4)
1 /* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
2 /*
3  * Copyright (c) 2017, Mellanox Technologies inc.  All rights reserved.
4  */
5 
6 #ifndef _UVERBS_IOCTL_
7 #define _UVERBS_IOCTL_
8 
9 #include <rdma/uverbs_types.h>
10 #include <linux/uaccess.h>
11 #include <rdma/rdma_user_ioctl.h>
12 #include <rdma/ib_user_ioctl_verbs.h>
13 #include <rdma/ib_user_ioctl_cmds.h>
14 
15 /*
16  * =======================================
17  *	Verbs action specifications
18  * =======================================
19  */
20 
21 enum uverbs_attr_type {
22 	UVERBS_ATTR_TYPE_NA,
23 	UVERBS_ATTR_TYPE_PTR_IN,
24 	UVERBS_ATTR_TYPE_PTR_OUT,
25 	UVERBS_ATTR_TYPE_IDR,
26 	UVERBS_ATTR_TYPE_FD,
27 	UVERBS_ATTR_TYPE_RAW_FD,
28 	UVERBS_ATTR_TYPE_ENUM_IN,
29 	UVERBS_ATTR_TYPE_IDRS_ARRAY,
30 };
31 
32 enum uverbs_obj_access {
33 	UVERBS_ACCESS_READ,
34 	UVERBS_ACCESS_WRITE,
35 	UVERBS_ACCESS_NEW,
36 	UVERBS_ACCESS_DESTROY
37 };
38 
39 /* Specification of a single attribute inside the ioctl message */
40 /* good size 16 */
41 struct uverbs_attr_spec {
42 	u8 type;
43 
44 	/*
45 	 * Support extending attributes by length. Allow the user to provide
46 	 * more bytes than ptr.len, but check that everything after is zero'd
47 	 * by the user.
48 	 */
49 	u8 zero_trailing:1;
50 	/*
51 	 * Valid only for PTR_IN. Allocate and copy the data inside
52 	 * the parser
53 	 */
54 	u8 alloc_and_copy:1;
55 	u8 mandatory:1;
56 	/* True if this is from UVERBS_ATTR_UHW */
57 	u8 is_udata:1;
58 
59 	union {
60 		struct {
61 			/* Current known size to kernel */
62 			u16 len;
63 			/* User isn't allowed to provide something < min_len */
64 			u16 min_len;
65 		} ptr;
66 
67 		struct {
68 			/*
69 			 * higher bits mean the namespace and lower bits mean
70 			 * the type id within the namespace.
71 			 */
72 			u16 obj_type;
73 			u8 access;
74 		} obj;
75 
76 		struct {
77 			u8 num_elems;
78 		} enum_def;
79 	} u;
80 
81 	/* This weird split lets us remove some padding */
82 	union {
83 		struct {
84 			/*
85 			 * The enum attribute can select one of the attributes
86 			 * contained in the ids array. Currently only PTR_IN
87 			 * attributes are supported in the ids array.
88 			 */
89 			const struct uverbs_attr_spec *ids;
90 		} enum_def;
91 
92 		struct {
93 			/*
94 			 * higher bits mean the namespace and lower bits mean
95 			 * the type id within the namespace.
96 			 */
97 			u16				obj_type;
98 			u16				min_len;
99 			u16				max_len;
100 			u8				access;
101 		} objs_arr;
102 	} u2;
103 };
104 
105 /*
106  * Information about the API is loaded into a radix tree. For IOCTL we start
107  * with a tuple of:
108  *  object_id, attr_id, method_id
109  *
110  * Which is a 48 bit value, with most of the bits guaranteed to be zero. Based
111  * on the current kernel support this is compressed into 16 bit key for the
112  * radix tree. Since this compression is entirely internal to the kernel the
113  * below limits can be revised if the kernel gains additional data.
114  *
115  * With 64 leafs per node this is a 3 level radix tree.
116  *
117  * The tree encodes multiple types, and uses a scheme where OBJ_ID,0,0 returns
118  * the object slot, and OBJ_ID,METH_ID,0 and returns the method slot.
119  *
120  * This also encodes the tables for the write() and write() extended commands
121  * using the coding
122  *   OBJ_ID,UVERBS_API_METHOD_IS_WRITE,command #
123  *   OBJ_ID,UVERBS_API_METHOD_IS_WRITE_EX,command_ex #
124  * ie the WRITE path is treated as a special method type in the ioctl
125  * framework.
126  */
127 enum uapi_radix_data {
128 	UVERBS_API_NS_FLAG = 1U << UVERBS_ID_NS_SHIFT,
129 
130 	UVERBS_API_ATTR_KEY_BITS = 6,
131 	UVERBS_API_ATTR_KEY_MASK = GENMASK(UVERBS_API_ATTR_KEY_BITS - 1, 0),
132 	UVERBS_API_ATTR_BKEY_LEN = (1 << UVERBS_API_ATTR_KEY_BITS) - 1,
133 	UVERBS_API_WRITE_KEY_NUM = 1 << UVERBS_API_ATTR_KEY_BITS,
134 
135 	UVERBS_API_METHOD_KEY_BITS = 5,
136 	UVERBS_API_METHOD_KEY_SHIFT = UVERBS_API_ATTR_KEY_BITS,
137 	UVERBS_API_METHOD_KEY_NUM_CORE = 22,
138 	UVERBS_API_METHOD_IS_WRITE = 30 << UVERBS_API_METHOD_KEY_SHIFT,
139 	UVERBS_API_METHOD_IS_WRITE_EX = 31 << UVERBS_API_METHOD_KEY_SHIFT,
140 	UVERBS_API_METHOD_KEY_NUM_DRIVER =
141 		(UVERBS_API_METHOD_IS_WRITE >> UVERBS_API_METHOD_KEY_SHIFT) -
142 		UVERBS_API_METHOD_KEY_NUM_CORE,
143 	UVERBS_API_METHOD_KEY_MASK = GENMASK(
144 		UVERBS_API_METHOD_KEY_BITS + UVERBS_API_METHOD_KEY_SHIFT - 1,
145 		UVERBS_API_METHOD_KEY_SHIFT),
146 
147 	UVERBS_API_OBJ_KEY_BITS = 5,
148 	UVERBS_API_OBJ_KEY_SHIFT =
149 		UVERBS_API_METHOD_KEY_BITS + UVERBS_API_METHOD_KEY_SHIFT,
150 	UVERBS_API_OBJ_KEY_NUM_CORE = 20,
151 	UVERBS_API_OBJ_KEY_NUM_DRIVER =
152 		(1 << UVERBS_API_OBJ_KEY_BITS) - UVERBS_API_OBJ_KEY_NUM_CORE,
153 	UVERBS_API_OBJ_KEY_MASK = GENMASK(31, UVERBS_API_OBJ_KEY_SHIFT),
154 
155 	/* This id guaranteed to not exist in the radix tree */
156 	UVERBS_API_KEY_ERR = 0xFFFFFFFF,
157 };
158 
159 static inline __attribute_const__ u32 uapi_key_obj(u32 id)
160 {
161 	if (id & UVERBS_API_NS_FLAG) {
162 		id &= ~UVERBS_API_NS_FLAG;
163 		if (id >= UVERBS_API_OBJ_KEY_NUM_DRIVER)
164 			return UVERBS_API_KEY_ERR;
165 		id = id + UVERBS_API_OBJ_KEY_NUM_CORE;
166 	} else {
167 		if (id >= UVERBS_API_OBJ_KEY_NUM_CORE)
168 			return UVERBS_API_KEY_ERR;
169 	}
170 
171 	return id << UVERBS_API_OBJ_KEY_SHIFT;
172 }
173 
174 static inline __attribute_const__ bool uapi_key_is_object(u32 key)
175 {
176 	return (key & ~UVERBS_API_OBJ_KEY_MASK) == 0;
177 }
178 
179 static inline __attribute_const__ u32 uapi_key_ioctl_method(u32 id)
180 {
181 	if (id & UVERBS_API_NS_FLAG) {
182 		id &= ~UVERBS_API_NS_FLAG;
183 		if (id >= UVERBS_API_METHOD_KEY_NUM_DRIVER)
184 			return UVERBS_API_KEY_ERR;
185 		id = id + UVERBS_API_METHOD_KEY_NUM_CORE;
186 	} else {
187 		id++;
188 		if (id >= UVERBS_API_METHOD_KEY_NUM_CORE)
189 			return UVERBS_API_KEY_ERR;
190 	}
191 
192 	return id << UVERBS_API_METHOD_KEY_SHIFT;
193 }
194 
195 static inline __attribute_const__ u32 uapi_key_write_method(u32 id)
196 {
197 	if (id >= UVERBS_API_WRITE_KEY_NUM)
198 		return UVERBS_API_KEY_ERR;
199 	return UVERBS_API_METHOD_IS_WRITE | id;
200 }
201 
202 static inline __attribute_const__ u32 uapi_key_write_ex_method(u32 id)
203 {
204 	if (id >= UVERBS_API_WRITE_KEY_NUM)
205 		return UVERBS_API_KEY_ERR;
206 	return UVERBS_API_METHOD_IS_WRITE_EX | id;
207 }
208 
209 static inline __attribute_const__ u32
210 uapi_key_attr_to_ioctl_method(u32 attr_key)
211 {
212 	return attr_key &
213 	       (UVERBS_API_OBJ_KEY_MASK | UVERBS_API_METHOD_KEY_MASK);
214 }
215 
216 static inline __attribute_const__ bool uapi_key_is_ioctl_method(u32 key)
217 {
218 	unsigned int method = key & UVERBS_API_METHOD_KEY_MASK;
219 
220 	return method != 0 && method < UVERBS_API_METHOD_IS_WRITE &&
221 	       (key & UVERBS_API_ATTR_KEY_MASK) == 0;
222 }
223 
224 static inline __attribute_const__ bool uapi_key_is_write_method(u32 key)
225 {
226 	return (key & UVERBS_API_METHOD_KEY_MASK) == UVERBS_API_METHOD_IS_WRITE;
227 }
228 
229 static inline __attribute_const__ bool uapi_key_is_write_ex_method(u32 key)
230 {
231 	return (key & UVERBS_API_METHOD_KEY_MASK) ==
232 	       UVERBS_API_METHOD_IS_WRITE_EX;
233 }
234 
235 static inline __attribute_const__ u32 uapi_key_attrs_start(u32 ioctl_method_key)
236 {
237 	/* 0 is the method slot itself */
238 	return ioctl_method_key + 1;
239 }
240 
241 static inline __attribute_const__ u32 uapi_key_attr(u32 id)
242 {
243 	/*
244 	 * The attr is designed to fit in the typical single radix tree node
245 	 * of 64 entries. Since allmost all methods have driver attributes we
246 	 * organize things so that the driver and core attributes interleave to
247 	 * reduce the length of the attributes array in typical cases.
248 	 */
249 	if (id & UVERBS_API_NS_FLAG) {
250 		id &= ~UVERBS_API_NS_FLAG;
251 		id++;
252 		if (id >= 1 << (UVERBS_API_ATTR_KEY_BITS - 1))
253 			return UVERBS_API_KEY_ERR;
254 		id = (id << 1) | 0;
255 	} else {
256 		if (id >= 1 << (UVERBS_API_ATTR_KEY_BITS - 1))
257 			return UVERBS_API_KEY_ERR;
258 		id = (id << 1) | 1;
259 	}
260 
261 	return id;
262 }
263 
264 /* Only true for ioctl methods */
265 static inline __attribute_const__ bool uapi_key_is_attr(u32 key)
266 {
267 	unsigned int method = key & UVERBS_API_METHOD_KEY_MASK;
268 
269 	return method != 0 && method < UVERBS_API_METHOD_IS_WRITE &&
270 	       (key & UVERBS_API_ATTR_KEY_MASK) != 0;
271 }
272 
273 /*
274  * This returns a value in the range [0 to UVERBS_API_ATTR_BKEY_LEN),
275  * basically it undoes the reservation of 0 in the ID numbering. attr_key
276  * must already be masked with UVERBS_API_ATTR_KEY_MASK, or be the output of
277  * uapi_key_attr().
278  */
279 static inline __attribute_const__ u32 uapi_bkey_attr(u32 attr_key)
280 {
281 	return attr_key - 1;
282 }
283 
284 static inline __attribute_const__ u32 uapi_bkey_to_key_attr(u32 attr_bkey)
285 {
286 	return attr_bkey + 1;
287 }
288 
289 /*
290  * =======================================
291  *	Verbs definitions
292  * =======================================
293  */
294 
295 struct uverbs_attr_def {
296 	u16                           id;
297 	struct uverbs_attr_spec       attr;
298 };
299 
300 struct uverbs_method_def {
301 	u16                                  id;
302 	/* Combination of bits from enum UVERBS_ACTION_FLAG_XXXX */
303 	u32				     flags;
304 	size_t				     num_attrs;
305 	const struct uverbs_attr_def * const (*attrs)[];
306 	int (*handler)(struct uverbs_attr_bundle *attrs);
307 };
308 
309 struct uverbs_object_def {
310 	u16					 id;
311 	const struct uverbs_obj_type	        *type_attrs;
312 	size_t				         num_methods;
313 	const struct uverbs_method_def * const (*methods)[];
314 };
315 
316 enum uapi_definition_kind {
317 	UAPI_DEF_END = 0,
318 	UAPI_DEF_OBJECT_START,
319 	UAPI_DEF_WRITE,
320 	UAPI_DEF_CHAIN_OBJ_TREE,
321 	UAPI_DEF_CHAIN,
322 	UAPI_DEF_IS_SUPPORTED_FUNC,
323 	UAPI_DEF_IS_SUPPORTED_DEV_FN,
324 };
325 
326 enum uapi_definition_scope {
327 	UAPI_SCOPE_OBJECT = 1,
328 	UAPI_SCOPE_METHOD = 2,
329 };
330 
331 struct uapi_definition {
332 	u8 kind;
333 	u8 scope;
334 	union {
335 		struct {
336 			u16 object_id;
337 		} object_start;
338 		struct {
339 			u16 command_num;
340 			u8 is_ex:1;
341 			u8 has_udata:1;
342 			u8 has_resp:1;
343 			u8 req_size;
344 			u8 resp_size;
345 		} write;
346 	};
347 
348 	union {
349 		bool (*func_is_supported)(struct ib_device *device);
350 		int (*func_write)(struct uverbs_attr_bundle *attrs);
351 		const struct uapi_definition *chain;
352 		const struct uverbs_object_def *chain_obj_tree;
353 		size_t needs_fn_offset;
354 	};
355 };
356 
357 /* Define things connected to object_id */
358 #define DECLARE_UVERBS_OBJECT(_object_id, ...)                                 \
359 	{                                                                      \
360 		.kind = UAPI_DEF_OBJECT_START,                                 \
361 		.object_start = { .object_id = _object_id },                   \
362 	},                                                                     \
363 		##__VA_ARGS__
364 
365 /* Use in a var_args of DECLARE_UVERBS_OBJECT */
366 #define DECLARE_UVERBS_WRITE(_command_num, _func, _cmd_desc, ...)              \
367 	{                                                                      \
368 		.kind = UAPI_DEF_WRITE,                                        \
369 		.scope = UAPI_SCOPE_OBJECT,                                    \
370 		.write = { .is_ex = 0, .command_num = _command_num },          \
371 		.func_write = _func,                                           \
372 		_cmd_desc,                                                     \
373 	},                                                                     \
374 		##__VA_ARGS__
375 
376 /* Use in a var_args of DECLARE_UVERBS_OBJECT */
377 #define DECLARE_UVERBS_WRITE_EX(_command_num, _func, _cmd_desc, ...)           \
378 	{                                                                      \
379 		.kind = UAPI_DEF_WRITE,                                        \
380 		.scope = UAPI_SCOPE_OBJECT,                                    \
381 		.write = { .is_ex = 1, .command_num = _command_num },          \
382 		.func_write = _func,                                           \
383 		_cmd_desc,                                                     \
384 	},                                                                     \
385 		##__VA_ARGS__
386 
387 /*
388  * Object is only supported if the function pointer named ibdev_fn in struct
389  * ib_device is not NULL.
390  */
391 #define UAPI_DEF_OBJ_NEEDS_FN(ibdev_fn)                                        \
392 	{                                                                      \
393 		.kind = UAPI_DEF_IS_SUPPORTED_DEV_FN,                          \
394 		.scope = UAPI_SCOPE_OBJECT,                                    \
395 		.needs_fn_offset =                                             \
396 			offsetof(struct ib_device_ops, ibdev_fn) +             \
397 			BUILD_BUG_ON_ZERO(sizeof_field(struct ib_device_ops,   \
398 						       ibdev_fn) !=            \
399 					  sizeof(void *)),                     \
400 	}
401 
402 /*
403  * Method is only supported if the function pointer named ibdev_fn in struct
404  * ib_device is not NULL.
405  */
406 #define UAPI_DEF_METHOD_NEEDS_FN(ibdev_fn)                                     \
407 	{                                                                      \
408 		.kind = UAPI_DEF_IS_SUPPORTED_DEV_FN,                          \
409 		.scope = UAPI_SCOPE_METHOD,                                    \
410 		.needs_fn_offset =                                             \
411 			offsetof(struct ib_device_ops, ibdev_fn) +             \
412 			BUILD_BUG_ON_ZERO(sizeof_field(struct ib_device_ops,   \
413 						       ibdev_fn) !=            \
414 					  sizeof(void *)),                     \
415 	}
416 
417 /* Call a function to determine if the entire object is supported or not */
418 #define UAPI_DEF_IS_OBJ_SUPPORTED(_func)                                       \
419 	{                                                                      \
420 		.kind = UAPI_DEF_IS_SUPPORTED_FUNC,                            \
421 		.scope = UAPI_SCOPE_OBJECT, .func_is_supported = _func,        \
422 	}
423 
424 /* Include another struct uapi_definition in this one */
425 #define UAPI_DEF_CHAIN(_def_var)                                               \
426 	{                                                                      \
427 		.kind = UAPI_DEF_CHAIN, .chain = _def_var,                     \
428 	}
429 
430 /* Temporary until the tree base description is replaced */
431 #define UAPI_DEF_CHAIN_OBJ_TREE(_object_enum, _object_ptr, ...)                \
432 	{                                                                      \
433 		.kind = UAPI_DEF_CHAIN_OBJ_TREE,                               \
434 		.object_start = { .object_id = _object_enum },                 \
435 		.chain_obj_tree = _object_ptr,                                 \
436 	},								       \
437 		##__VA_ARGS__
438 #define UAPI_DEF_CHAIN_OBJ_TREE_NAMED(_object_enum, ...)                       \
439 	UAPI_DEF_CHAIN_OBJ_TREE(_object_enum, &UVERBS_OBJECT(_object_enum),    \
440 				##__VA_ARGS__)
441 
442 /*
443  * =======================================
444  *	Attribute Specifications
445  * =======================================
446  */
447 
448 #define UVERBS_ATTR_SIZE(_min_len, _len)			\
449 	.u.ptr.min_len = _min_len, .u.ptr.len = _len
450 
451 #define UVERBS_ATTR_NO_DATA() UVERBS_ATTR_SIZE(0, 0)
452 
453 /*
454  * Specifies a uapi structure that cannot be extended. The user must always
455  * supply the whole structure and nothing more. The structure must be declared
456  * in a header under include/uapi/rdma.
457  */
458 #define UVERBS_ATTR_TYPE(_type)					\
459 	.u.ptr.min_len = sizeof(_type), .u.ptr.len = sizeof(_type)
460 /*
461  * Specifies a uapi structure where the user must provide at least up to
462  * member 'last'.  Anything after last and up until the end of the structure
463  * can be non-zero, anything longer than the end of the structure must be
464  * zero. The structure must be declared in a header under include/uapi/rdma.
465  */
466 #define UVERBS_ATTR_STRUCT(_type, _last)                                       \
467 	.zero_trailing = 1,                                                    \
468 	UVERBS_ATTR_SIZE(offsetofend(_type, _last), sizeof(_type))
469 /*
470  * Specifies at least min_len bytes must be passed in, but the amount can be
471  * larger, up to the protocol maximum size. No check for zeroing is done.
472  */
473 #define UVERBS_ATTR_MIN_SIZE(_min_len) UVERBS_ATTR_SIZE(_min_len, USHRT_MAX)
474 
475 /* Must be used in the '...' of any UVERBS_ATTR */
476 #define UA_ALLOC_AND_COPY .alloc_and_copy = 1
477 #define UA_MANDATORY .mandatory = 1
478 #define UA_OPTIONAL .mandatory = 0
479 
480 /*
481  * min_len must be bigger than 0 and _max_len must be smaller than 4095.  Only
482  * READ\WRITE accesses are supported.
483  */
484 #define UVERBS_ATTR_IDRS_ARR(_attr_id, _idr_type, _access, _min_len, _max_len, \
485 			     ...)                                              \
486 	(&(const struct uverbs_attr_def){                                      \
487 		.id = (_attr_id) +                                             \
488 		      BUILD_BUG_ON_ZERO((_min_len) == 0 ||                     \
489 					(_max_len) >                           \
490 						PAGE_SIZE / sizeof(void *) ||  \
491 					(_min_len) > (_max_len) ||             \
492 					(_access) == UVERBS_ACCESS_NEW ||      \
493 					(_access) == UVERBS_ACCESS_DESTROY),   \
494 		.attr = { .type = UVERBS_ATTR_TYPE_IDRS_ARRAY,                 \
495 			  .u2.objs_arr.obj_type = _idr_type,                   \
496 			  .u2.objs_arr.access = _access,                       \
497 			  .u2.objs_arr.min_len = _min_len,                     \
498 			  .u2.objs_arr.max_len = _max_len,                     \
499 			  __VA_ARGS__ } })
500 
501 /*
502  * Only for use with UVERBS_ATTR_IDR, allows any uobject type to be accepted,
503  * the user must validate the type of the uobject instead.
504  */
505 #define UVERBS_IDR_ANY_OBJECT 0xFFFF
506 
507 #define UVERBS_ATTR_IDR(_attr_id, _idr_type, _access, ...)                     \
508 	(&(const struct uverbs_attr_def){                                      \
509 		.id = _attr_id,                                                \
510 		.attr = { .type = UVERBS_ATTR_TYPE_IDR,                        \
511 			  .u.obj.obj_type = _idr_type,                         \
512 			  .u.obj.access = _access,                             \
513 			  __VA_ARGS__ } })
514 
515 #define UVERBS_ATTR_FD(_attr_id, _fd_type, _access, ...)                       \
516 	(&(const struct uverbs_attr_def){                                      \
517 		.id = (_attr_id) +                                             \
518 		      BUILD_BUG_ON_ZERO((_access) != UVERBS_ACCESS_NEW &&      \
519 					(_access) != UVERBS_ACCESS_READ),      \
520 		.attr = { .type = UVERBS_ATTR_TYPE_FD,                         \
521 			  .u.obj.obj_type = _fd_type,                          \
522 			  .u.obj.access = _access,                             \
523 			  __VA_ARGS__ } })
524 
525 #define UVERBS_ATTR_RAW_FD(_attr_id, ...)                                      \
526 	(&(const struct uverbs_attr_def){                                      \
527 		.id = (_attr_id),                                              \
528 		.attr = { .type = UVERBS_ATTR_TYPE_RAW_FD, __VA_ARGS__ } })
529 
530 #define UVERBS_ATTR_PTR_IN(_attr_id, _type, ...)                               \
531 	(&(const struct uverbs_attr_def){                                      \
532 		.id = _attr_id,                                                \
533 		.attr = { .type = UVERBS_ATTR_TYPE_PTR_IN,                     \
534 			  _type,                                               \
535 			  __VA_ARGS__ } })
536 
537 #define UVERBS_ATTR_PTR_OUT(_attr_id, _type, ...)                              \
538 	(&(const struct uverbs_attr_def){                                      \
539 		.id = _attr_id,                                                \
540 		.attr = { .type = UVERBS_ATTR_TYPE_PTR_OUT,                    \
541 			  _type,                                               \
542 			  __VA_ARGS__ } })
543 
544 /* _enum_arry should be a 'static const union uverbs_attr_spec[]' */
545 #define UVERBS_ATTR_ENUM_IN(_attr_id, _enum_arr, ...)                          \
546 	(&(const struct uverbs_attr_def){                                      \
547 		.id = _attr_id,                                                \
548 		.attr = { .type = UVERBS_ATTR_TYPE_ENUM_IN,                    \
549 			  .u2.enum_def.ids = _enum_arr,                        \
550 			  .u.enum_def.num_elems = ARRAY_SIZE(_enum_arr),       \
551 			  __VA_ARGS__ },                                       \
552 	})
553 
554 /* An input value that is a member in the enum _enum_type. */
555 #define UVERBS_ATTR_CONST_IN(_attr_id, _enum_type, ...)                        \
556 	UVERBS_ATTR_PTR_IN(                                                    \
557 		_attr_id,                                                      \
558 		UVERBS_ATTR_SIZE(                                              \
559 			sizeof(u64) + BUILD_BUG_ON_ZERO(!sizeof(_enum_type)),  \
560 			sizeof(u64)),                                          \
561 		__VA_ARGS__)
562 
563 /*
564  * An input value that is a bitwise combination of values of _enum_type.
565  * This permits the flag value to be passed as either a u32 or u64, it must
566  * be retrieved via uverbs_get_flag().
567  */
568 #define UVERBS_ATTR_FLAGS_IN(_attr_id, _enum_type, ...)                        \
569 	UVERBS_ATTR_PTR_IN(                                                    \
570 		_attr_id,                                                      \
571 		UVERBS_ATTR_SIZE(sizeof(u32) + BUILD_BUG_ON_ZERO(              \
572 						       !sizeof(_enum_type *)), \
573 				 sizeof(u64)),                                 \
574 		__VA_ARGS__)
575 
576 /*
577  * This spec is used in order to pass information to the hardware driver in a
578  * legacy way. Every verb that could get driver specific data should get this
579  * spec.
580  */
581 #define UVERBS_ATTR_UHW()                                                      \
582 	UVERBS_ATTR_PTR_IN(UVERBS_ATTR_UHW_IN,                                 \
583 			   UVERBS_ATTR_MIN_SIZE(0),			       \
584 			   UA_OPTIONAL,                                        \
585 			   .is_udata = 1),				       \
586 	UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_UHW_OUT,                               \
587 			    UVERBS_ATTR_MIN_SIZE(0),			       \
588 			    UA_OPTIONAL,                                       \
589 			    .is_udata = 1)
590 
591 /* =================================================
592  *              Parsing infrastructure
593  * =================================================
594  */
595 
596 
597 struct uverbs_ptr_attr {
598 	/*
599 	 * If UVERBS_ATTR_SPEC_F_ALLOC_AND_COPY is set then the 'ptr' is
600 	 * used.
601 	 */
602 	union {
603 		void *ptr;
604 		u64 data;
605 	};
606 	u16		len;
607 	u16		uattr_idx;
608 	u8		enum_id;
609 };
610 
611 struct uverbs_obj_attr {
612 	struct ib_uobject		*uobject;
613 	const struct uverbs_api_attr	*attr_elm;
614 };
615 
616 struct uverbs_objs_arr_attr {
617 	struct ib_uobject **uobjects;
618 	u16 len;
619 };
620 
621 struct uverbs_attr {
622 	union {
623 		struct uverbs_ptr_attr	ptr_attr;
624 		struct uverbs_obj_attr	obj_attr;
625 		struct uverbs_objs_arr_attr objs_arr_attr;
626 	};
627 };
628 
629 struct uverbs_attr_bundle {
630 	struct ib_udata driver_udata;
631 	struct ib_udata ucore;
632 	struct ib_uverbs_file *ufile;
633 	struct ib_ucontext *context;
634 	struct ib_uobject *uobject;
635 	DECLARE_BITMAP(attr_present, UVERBS_API_ATTR_BKEY_LEN);
636 	struct uverbs_attr attrs[];
637 };
638 
639 static inline bool uverbs_attr_is_valid(const struct uverbs_attr_bundle *attrs_bundle,
640 					unsigned int idx)
641 {
642 	return test_bit(uapi_bkey_attr(uapi_key_attr(idx)),
643 			attrs_bundle->attr_present);
644 }
645 
646 /**
647  * rdma_udata_to_drv_context - Helper macro to get the driver's context out of
648  *                             ib_udata which is embedded in uverbs_attr_bundle.
649  *
650  * If udata is not NULL this cannot fail. Otherwise a NULL udata will result
651  * in a NULL ucontext pointer, as a safety precaution. Callers should be using
652  * 'udata' to determine if the driver call is in user or kernel mode, not
653  * 'ucontext'.
654  *
655  */
656 static inline struct uverbs_attr_bundle *
657 rdma_udata_to_uverbs_attr_bundle(struct ib_udata *udata)
658 {
659 	return container_of(udata, struct uverbs_attr_bundle, driver_udata);
660 }
661 
662 #define rdma_udata_to_drv_context(udata, drv_dev_struct, member)                \
663 	(udata ? container_of(rdma_udata_to_uverbs_attr_bundle(udata)->context, \
664 			      drv_dev_struct, member) : (drv_dev_struct *)NULL)
665 
666 #define IS_UVERBS_COPY_ERR(_ret)		((_ret) && (_ret) != -ENOENT)
667 
668 static inline const struct uverbs_attr *uverbs_attr_get(const struct uverbs_attr_bundle *attrs_bundle,
669 							u16 idx)
670 {
671 	if (!uverbs_attr_is_valid(attrs_bundle, idx))
672 		return ERR_PTR(-ENOENT);
673 
674 	return &attrs_bundle->attrs[uapi_bkey_attr(uapi_key_attr(idx))];
675 }
676 
677 static inline int uverbs_attr_get_enum_id(const struct uverbs_attr_bundle *attrs_bundle,
678 					  u16 idx)
679 {
680 	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
681 
682 	if (IS_ERR(attr))
683 		return PTR_ERR(attr);
684 
685 	return attr->ptr_attr.enum_id;
686 }
687 
688 static inline void *uverbs_attr_get_obj(const struct uverbs_attr_bundle *attrs_bundle,
689 					u16 idx)
690 {
691 	const struct uverbs_attr *attr;
692 
693 	attr = uverbs_attr_get(attrs_bundle, idx);
694 	if (IS_ERR(attr))
695 		return ERR_CAST(attr);
696 
697 	return attr->obj_attr.uobject->object;
698 }
699 
700 static inline struct ib_uobject *uverbs_attr_get_uobject(const struct uverbs_attr_bundle *attrs_bundle,
701 							 u16 idx)
702 {
703 	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
704 
705 	if (IS_ERR(attr))
706 		return ERR_CAST(attr);
707 
708 	return attr->obj_attr.uobject;
709 }
710 
711 static inline int
712 uverbs_attr_get_len(const struct uverbs_attr_bundle *attrs_bundle, u16 idx)
713 {
714 	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
715 
716 	if (IS_ERR(attr))
717 		return PTR_ERR(attr);
718 
719 	return attr->ptr_attr.len;
720 }
721 
722 void uverbs_finalize_uobj_create(const struct uverbs_attr_bundle *attrs_bundle,
723 				 u16 idx);
724 
725 /*
726  * uverbs_attr_ptr_get_array_size() - Get array size pointer by a ptr
727  * attribute.
728  * @attrs: The attribute bundle
729  * @idx: The ID of the attribute
730  * @elem_size: The size of the element in the array
731  */
732 static inline int
733 uverbs_attr_ptr_get_array_size(struct uverbs_attr_bundle *attrs, u16 idx,
734 			       size_t elem_size)
735 {
736 	int size = uverbs_attr_get_len(attrs, idx);
737 
738 	if (size < 0)
739 		return size;
740 
741 	if (size % elem_size)
742 		return -EINVAL;
743 
744 	return size / elem_size;
745 }
746 
747 /**
748  * uverbs_attr_get_uobjs_arr() - Provides array's properties for attribute for
749  * UVERBS_ATTR_TYPE_IDRS_ARRAY.
750  * @arr: Returned pointer to array of pointers for uobjects or NULL if
751  *       the attribute isn't provided.
752  *
753  * Return: The array length or 0 if no attribute was provided.
754  */
755 static inline int uverbs_attr_get_uobjs_arr(
756 	const struct uverbs_attr_bundle *attrs_bundle, u16 attr_idx,
757 	struct ib_uobject ***arr)
758 {
759 	const struct uverbs_attr *attr =
760 			uverbs_attr_get(attrs_bundle, attr_idx);
761 
762 	if (IS_ERR(attr)) {
763 		*arr = NULL;
764 		return 0;
765 	}
766 
767 	*arr = attr->objs_arr_attr.uobjects;
768 
769 	return attr->objs_arr_attr.len;
770 }
771 
772 static inline bool uverbs_attr_ptr_is_inline(const struct uverbs_attr *attr)
773 {
774 	return attr->ptr_attr.len <= sizeof(attr->ptr_attr.data);
775 }
776 
777 static inline void *uverbs_attr_get_alloced_ptr(
778 	const struct uverbs_attr_bundle *attrs_bundle, u16 idx)
779 {
780 	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
781 
782 	if (IS_ERR(attr))
783 		return (void *)attr;
784 
785 	return uverbs_attr_ptr_is_inline(attr) ? (void *)&attr->ptr_attr.data :
786 						 attr->ptr_attr.ptr;
787 }
788 
789 static inline int _uverbs_copy_from(void *to,
790 				    const struct uverbs_attr_bundle *attrs_bundle,
791 				    size_t idx,
792 				    size_t size)
793 {
794 	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
795 
796 	if (IS_ERR(attr))
797 		return PTR_ERR(attr);
798 
799 	/*
800 	 * Validation ensures attr->ptr_attr.len >= size. If the caller is
801 	 * using UVERBS_ATTR_SPEC_F_MIN_SZ_OR_ZERO then it must call
802 	 * uverbs_copy_from_or_zero.
803 	 */
804 	if (unlikely(size < attr->ptr_attr.len))
805 		return -EINVAL;
806 
807 	if (uverbs_attr_ptr_is_inline(attr))
808 		memcpy(to, &attr->ptr_attr.data, attr->ptr_attr.len);
809 	else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
810 				attr->ptr_attr.len))
811 		return -EFAULT;
812 
813 	return 0;
814 }
815 
816 static inline int _uverbs_copy_from_or_zero(void *to,
817 					    const struct uverbs_attr_bundle *attrs_bundle,
818 					    size_t idx,
819 					    size_t size)
820 {
821 	const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
822 	size_t min_size;
823 
824 	if (IS_ERR(attr))
825 		return PTR_ERR(attr);
826 
827 	min_size = min_t(size_t, size, attr->ptr_attr.len);
828 
829 	if (uverbs_attr_ptr_is_inline(attr))
830 		memcpy(to, &attr->ptr_attr.data, min_size);
831 	else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
832 				min_size))
833 		return -EFAULT;
834 
835 	if (size > min_size)
836 		memset(to + min_size, 0, size - min_size);
837 
838 	return 0;
839 }
840 
841 #define uverbs_copy_from(to, attrs_bundle, idx)				      \
842 	_uverbs_copy_from(to, attrs_bundle, idx, sizeof(*to))
843 
844 #define uverbs_copy_from_or_zero(to, attrs_bundle, idx)			      \
845 	_uverbs_copy_from_or_zero(to, attrs_bundle, idx, sizeof(*to))
846 
847 static inline struct ib_ucontext *
848 ib_uverbs_get_ucontext(const struct uverbs_attr_bundle *attrs)
849 {
850 	return ib_uverbs_get_ucontext_file(attrs->ufile);
851 }
852 
853 #if IS_ENABLED(CONFIG_INFINIBAND_USER_ACCESS)
854 int uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle,
855 		       size_t idx, u64 allowed_bits);
856 int uverbs_get_flags32(u32 *to, const struct uverbs_attr_bundle *attrs_bundle,
857 		       size_t idx, u64 allowed_bits);
858 int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle, size_t idx,
859 		   const void *from, size_t size);
860 __malloc void *_uverbs_alloc(struct uverbs_attr_bundle *bundle, size_t size,
861 			     gfp_t flags);
862 
863 static inline __malloc void *uverbs_alloc(struct uverbs_attr_bundle *bundle,
864 					  size_t size)
865 {
866 	return _uverbs_alloc(bundle, size, GFP_KERNEL);
867 }
868 
869 static inline __malloc void *uverbs_zalloc(struct uverbs_attr_bundle *bundle,
870 					   size_t size)
871 {
872 	return _uverbs_alloc(bundle, size, GFP_KERNEL | __GFP_ZERO);
873 }
874 
875 static inline __malloc void *uverbs_kcalloc(struct uverbs_attr_bundle *bundle,
876 					    size_t n, size_t size)
877 {
878 	size_t bytes;
879 
880 	if (unlikely(check_mul_overflow(n, size, &bytes)))
881 		return ERR_PTR(-EOVERFLOW);
882 	return uverbs_zalloc(bundle, bytes);
883 }
884 
885 int _uverbs_get_const_signed(s64 *to,
886 			     const struct uverbs_attr_bundle *attrs_bundle,
887 			     size_t idx, s64 lower_bound, u64 upper_bound,
888 			     s64 *def_val);
889 int _uverbs_get_const_unsigned(u64 *to,
890 			       const struct uverbs_attr_bundle *attrs_bundle,
891 			       size_t idx, u64 upper_bound, u64 *def_val);
892 int uverbs_copy_to_struct_or_zero(const struct uverbs_attr_bundle *bundle,
893 				  size_t idx, const void *from, size_t size);
894 #else
895 static inline int
896 uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle,
897 		   size_t idx, u64 allowed_bits)
898 {
899 	return -EINVAL;
900 }
901 static inline int
902 uverbs_get_flags32(u32 *to, const struct uverbs_attr_bundle *attrs_bundle,
903 		   size_t idx, u64 allowed_bits)
904 {
905 	return -EINVAL;
906 }
907 static inline int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle,
908 				 size_t idx, const void *from, size_t size)
909 {
910 	return -EINVAL;
911 }
912 static inline __malloc void *uverbs_alloc(struct uverbs_attr_bundle *bundle,
913 					  size_t size)
914 {
915 	return ERR_PTR(-EINVAL);
916 }
917 static inline __malloc void *uverbs_zalloc(struct uverbs_attr_bundle *bundle,
918 					   size_t size)
919 {
920 	return ERR_PTR(-EINVAL);
921 }
922 static inline int
923 _uverbs_get_const(s64 *to, const struct uverbs_attr_bundle *attrs_bundle,
924 		  size_t idx, s64 lower_bound, u64 upper_bound,
925 		  s64 *def_val)
926 {
927 	return -EINVAL;
928 }
929 static inline int
930 uverbs_copy_to_struct_or_zero(const struct uverbs_attr_bundle *bundle,
931 			      size_t idx, const void *from, size_t size)
932 {
933 	return -EINVAL;
934 }
935 static inline int
936 _uverbs_get_const_signed(s64 *to,
937 			 const struct uverbs_attr_bundle *attrs_bundle,
938 			 size_t idx, s64 lower_bound, u64 upper_bound,
939 			 s64 *def_val)
940 {
941 	return -EINVAL;
942 }
943 static inline int
944 _uverbs_get_const_unsigned(u64 *to,
945 			   const struct uverbs_attr_bundle *attrs_bundle,
946 			   size_t idx, u64 upper_bound, u64 *def_val)
947 {
948 	return -EINVAL;
949 }
950 #endif
951 
952 #define uverbs_get_const_signed(_to, _attrs_bundle, _idx)                      \
953 	({                                                                     \
954 		s64 _val;                                                      \
955 		int _ret =                                                     \
956 			_uverbs_get_const_signed(&_val, _attrs_bundle, _idx,   \
957 					  type_min(typeof(*(_to))),            \
958 					  type_max(typeof(*(_to))), NULL);     \
959 		(*(_to)) = _val;                                               \
960 		_ret;                                                          \
961 	})
962 
963 #define uverbs_get_const_unsigned(_to, _attrs_bundle, _idx)                    \
964 	({                                                                     \
965 		u64 _val;                                                      \
966 		int _ret =                                                     \
967 			_uverbs_get_const_unsigned(&_val, _attrs_bundle, _idx, \
968 					  type_max(typeof(*(_to))), NULL);     \
969 		(*(_to)) = _val;                                               \
970 		_ret;                                                          \
971 	})
972 
973 #define uverbs_get_const_default_signed(_to, _attrs_bundle, _idx, _default)    \
974 	({                                                                     \
975 		s64 _val;                                                      \
976 		s64 _def_val = _default;                                       \
977 		int _ret =                                                     \
978 			_uverbs_get_const_signed(&_val, _attrs_bundle, _idx,   \
979 				type_min(typeof(*(_to))),                      \
980 				type_max(typeof(*(_to))), &_def_val);          \
981 		(*(_to)) = _val;                                               \
982 		_ret;                                                          \
983 	})
984 
985 #define uverbs_get_const_default_unsigned(_to, _attrs_bundle, _idx, _default)  \
986 	({                                                                     \
987 		u64 _val;                                                      \
988 		u64 _def_val = _default;                                       \
989 		int _ret =                                                     \
990 			_uverbs_get_const_unsigned(&_val, _attrs_bundle, _idx, \
991 				type_max(typeof(*(_to))), &_def_val);          \
992 		(*(_to)) = _val;                                               \
993 		_ret;                                                          \
994 	})
995 
996 #define uverbs_get_const(_to, _attrs_bundle, _idx)                             \
997 	(is_signed_type(typeof(*(_to))) ?                                      \
998 		 uverbs_get_const_signed(_to, _attrs_bundle, _idx) :           \
999 		 uverbs_get_const_unsigned(_to, _attrs_bundle, _idx))          \
1000 
1001 #define uverbs_get_const_default(_to, _attrs_bundle, _idx, _default)           \
1002 	(is_signed_type(typeof(*(_to))) ?                                      \
1003 		 uverbs_get_const_default_signed(_to, _attrs_bundle, _idx,     \
1004 						  _default) :                  \
1005 		 uverbs_get_const_default_unsigned(_to, _attrs_bundle, _idx,   \
1006 						    _default))
1007 
1008 static inline int
1009 uverbs_get_raw_fd(int *to, const struct uverbs_attr_bundle *attrs_bundle,
1010 		  size_t idx)
1011 {
1012 	return uverbs_get_const_signed(to, attrs_bundle, idx);
1013 }
1014 
1015 #endif
1016