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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
21enum 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
32enum 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 */
41struct 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 */
127enum 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
159static 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
174static inline __attribute_const__ bool uapi_key_is_object(u32 key)
175{
176 return (key & ~UVERBS_API_OBJ_KEY_MASK) == 0;
177}
178
179static 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
195static 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
202static 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
209static inline __attribute_const__ u32
210uapi_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
216static 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
224static 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
229static 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
235static 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
241static 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 */
265static 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 */
279static inline __attribute_const__ u32 uapi_bkey_attr(u32 attr_key)
280{
281 return attr_key - 1;
282}
283
284static 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
295struct uverbs_attr_def {
296 u16 id;
297 struct uverbs_attr_spec attr;
298};
299
300struct 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
309struct 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
316enum 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
326enum uapi_definition_scope {
327 UAPI_SCOPE_OBJECT = 1,
328 UAPI_SCOPE_METHOD = 2,
329};
330
331struct 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, \
440 PTR_IF(IS_ENABLED(CONFIG_INFINIBAND_USER_ACCESS), \
441 &UVERBS_OBJECT(_object_enum)), \
442 ##__VA_ARGS__)
443
444/*
445 * =======================================
446 * Attribute Specifications
447 * =======================================
448 */
449
450#define UVERBS_ATTR_SIZE(_min_len, _len) \
451 .u.ptr.min_len = _min_len, .u.ptr.len = _len
452
453#define UVERBS_ATTR_NO_DATA() UVERBS_ATTR_SIZE(0, 0)
454
455/*
456 * Specifies a uapi structure that cannot be extended. The user must always
457 * supply the whole structure and nothing more. The structure must be declared
458 * in a header under include/uapi/rdma.
459 */
460#define UVERBS_ATTR_TYPE(_type) \
461 .u.ptr.min_len = sizeof(_type), .u.ptr.len = sizeof(_type)
462/*
463 * Specifies a uapi structure where the user must provide at least up to
464 * member 'last'. Anything after last and up until the end of the structure
465 * can be non-zero, anything longer than the end of the structure must be
466 * zero. The structure must be declared in a header under include/uapi/rdma.
467 */
468#define UVERBS_ATTR_STRUCT(_type, _last) \
469 .zero_trailing = 1, \
470 UVERBS_ATTR_SIZE(offsetofend(_type, _last), sizeof(_type))
471/*
472 * Specifies at least min_len bytes must be passed in, but the amount can be
473 * larger, up to the protocol maximum size. No check for zeroing is done.
474 */
475#define UVERBS_ATTR_MIN_SIZE(_min_len) UVERBS_ATTR_SIZE(_min_len, USHRT_MAX)
476
477/* Must be used in the '...' of any UVERBS_ATTR */
478#define UA_ALLOC_AND_COPY .alloc_and_copy = 1
479#define UA_MANDATORY .mandatory = 1
480#define UA_OPTIONAL .mandatory = 0
481
482/*
483 * min_len must be bigger than 0 and _max_len must be smaller than 4095. Only
484 * READ\WRITE accesses are supported.
485 */
486#define UVERBS_ATTR_IDRS_ARR(_attr_id, _idr_type, _access, _min_len, _max_len, \
487 ...) \
488 (&(const struct uverbs_attr_def){ \
489 .id = (_attr_id) + \
490 BUILD_BUG_ON_ZERO((_min_len) == 0 || \
491 (_max_len) > \
492 PAGE_SIZE / sizeof(void *) || \
493 (_min_len) > (_max_len) || \
494 (_access) == UVERBS_ACCESS_NEW || \
495 (_access) == UVERBS_ACCESS_DESTROY), \
496 .attr = { .type = UVERBS_ATTR_TYPE_IDRS_ARRAY, \
497 .u2.objs_arr.obj_type = _idr_type, \
498 .u2.objs_arr.access = _access, \
499 .u2.objs_arr.min_len = _min_len, \
500 .u2.objs_arr.max_len = _max_len, \
501 __VA_ARGS__ } })
502
503/*
504 * Only for use with UVERBS_ATTR_IDR, allows any uobject type to be accepted,
505 * the user must validate the type of the uobject instead.
506 */
507#define UVERBS_IDR_ANY_OBJECT 0xFFFF
508
509#define UVERBS_ATTR_IDR(_attr_id, _idr_type, _access, ...) \
510 (&(const struct uverbs_attr_def){ \
511 .id = _attr_id, \
512 .attr = { .type = UVERBS_ATTR_TYPE_IDR, \
513 .u.obj.obj_type = _idr_type, \
514 .u.obj.access = _access, \
515 __VA_ARGS__ } })
516
517#define UVERBS_ATTR_FD(_attr_id, _fd_type, _access, ...) \
518 (&(const struct uverbs_attr_def){ \
519 .id = (_attr_id) + \
520 BUILD_BUG_ON_ZERO((_access) != UVERBS_ACCESS_NEW && \
521 (_access) != UVERBS_ACCESS_READ), \
522 .attr = { .type = UVERBS_ATTR_TYPE_FD, \
523 .u.obj.obj_type = _fd_type, \
524 .u.obj.access = _access, \
525 __VA_ARGS__ } })
526
527#define UVERBS_ATTR_RAW_FD(_attr_id, ...) \
528 (&(const struct uverbs_attr_def){ \
529 .id = (_attr_id), \
530 .attr = { .type = UVERBS_ATTR_TYPE_RAW_FD, __VA_ARGS__ } })
531
532#define UVERBS_ATTR_PTR_IN(_attr_id, _type, ...) \
533 (&(const struct uverbs_attr_def){ \
534 .id = _attr_id, \
535 .attr = { .type = UVERBS_ATTR_TYPE_PTR_IN, \
536 _type, \
537 __VA_ARGS__ } })
538
539#define UVERBS_ATTR_PTR_OUT(_attr_id, _type, ...) \
540 (&(const struct uverbs_attr_def){ \
541 .id = _attr_id, \
542 .attr = { .type = UVERBS_ATTR_TYPE_PTR_OUT, \
543 _type, \
544 __VA_ARGS__ } })
545
546/* _enum_arry should be a 'static const union uverbs_attr_spec[]' */
547#define UVERBS_ATTR_ENUM_IN(_attr_id, _enum_arr, ...) \
548 (&(const struct uverbs_attr_def){ \
549 .id = _attr_id, \
550 .attr = { .type = UVERBS_ATTR_TYPE_ENUM_IN, \
551 .u2.enum_def.ids = _enum_arr, \
552 .u.enum_def.num_elems = ARRAY_SIZE(_enum_arr), \
553 __VA_ARGS__ }, \
554 })
555
556/* An input value that is a member in the enum _enum_type. */
557#define UVERBS_ATTR_CONST_IN(_attr_id, _enum_type, ...) \
558 UVERBS_ATTR_PTR_IN( \
559 _attr_id, \
560 UVERBS_ATTR_SIZE( \
561 sizeof(u64) + BUILD_BUG_ON_ZERO(!sizeof(_enum_type)), \
562 sizeof(u64)), \
563 __VA_ARGS__)
564
565/*
566 * An input value that is a bitwise combination of values of _enum_type.
567 * This permits the flag value to be passed as either a u32 or u64, it must
568 * be retrieved via uverbs_get_flag().
569 */
570#define UVERBS_ATTR_FLAGS_IN(_attr_id, _enum_type, ...) \
571 UVERBS_ATTR_PTR_IN( \
572 _attr_id, \
573 UVERBS_ATTR_SIZE(sizeof(u32) + BUILD_BUG_ON_ZERO( \
574 !sizeof(_enum_type *)), \
575 sizeof(u64)), \
576 __VA_ARGS__)
577
578/*
579 * This spec is used in order to pass information to the hardware driver in a
580 * legacy way. Every verb that could get driver specific data should get this
581 * spec.
582 */
583#define UVERBS_ATTR_UHW() \
584 UVERBS_ATTR_PTR_IN(UVERBS_ATTR_UHW_IN, \
585 UVERBS_ATTR_MIN_SIZE(0), \
586 UA_OPTIONAL, \
587 .is_udata = 1), \
588 UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_UHW_OUT, \
589 UVERBS_ATTR_MIN_SIZE(0), \
590 UA_OPTIONAL, \
591 .is_udata = 1)
592
593/*
594 * Per-attribute UMEM descriptor. The payload is a single
595 * struct ib_uverbs_buffer_desc identifying a memory region backed by
596 * dma-buf or user virtual address. _access selects UA_OPTIONAL or
597 * UA_MANDATORY. Drivers obtain a umem from the attribute via the
598 * ib_umem_get_*() wrapper helpers.
599 */
600#define UVERBS_ATTR_UMEM(_attr_id, _access) \
601 UVERBS_ATTR_PTR_IN(_attr_id, \
602 UVERBS_ATTR_TYPE(struct ib_uverbs_buffer_desc), \
603 _access)
604
605/*
606 * Bit masks of the @flags / @optional_flags fields of struct
607 * ib_uverbs_buffer_desc that the kernel understands. @flags is strict:
608 * any bit outside the known mask makes the call fail with -EINVAL.
609 * @optional_flags is advisory: bits outside the known mask are silently
610 * dropped. Both masks are extended as new bits are introduced.
611 */
612#define IB_UVERBS_BUFFER_DESC_FLAGS_KNOWN_MASK 0U
613#define IB_UVERBS_BUFFER_DESC_OPTIONAL_FLAGS_KNOWN_MASK 0U
614
615/* =================================================
616 * Parsing infrastructure
617 * =================================================
618 */
619
620
621struct uverbs_ptr_attr {
622 /*
623 * If UVERBS_ATTR_SPEC_F_ALLOC_AND_COPY is set then the 'ptr' is
624 * used.
625 */
626 union {
627 void *ptr;
628 u64 data;
629 };
630 u16 len;
631 u16 uattr_idx;
632 u8 enum_id;
633};
634
635struct uverbs_obj_attr {
636 struct ib_uobject *uobject;
637 const struct uverbs_api_attr *attr_elm;
638};
639
640struct uverbs_objs_arr_attr {
641 struct ib_uobject **uobjects;
642 u16 len;
643};
644
645struct uverbs_attr {
646 union {
647 struct uverbs_ptr_attr ptr_attr;
648 struct uverbs_obj_attr obj_attr;
649 struct uverbs_objs_arr_attr objs_arr_attr;
650 };
651};
652
653struct uverbs_attr_bundle {
654 struct_group_tagged(uverbs_attr_bundle_hdr, hdr,
655 struct ib_udata driver_udata;
656 struct ib_udata ucore;
657 struct ib_uverbs_file *ufile;
658 struct ib_ucontext *context;
659 struct ib_uobject *uobject;
660 const struct uverbs_api_ioctl_method *method_elm;
661 DECLARE_BITMAP(attr_present, UVERBS_API_ATTR_BKEY_LEN);
662 );
663 struct uverbs_attr attrs[];
664};
665
666static inline bool uverbs_attr_is_valid(const struct uverbs_attr_bundle *attrs_bundle,
667 unsigned int idx)
668{
669 return test_bit(uapi_bkey_attr(uapi_key_attr(idx)),
670 attrs_bundle->attr_present);
671}
672
673/**
674 * rdma_udata_to_drv_context - Helper macro to get the driver's context out of
675 * ib_udata which is embedded in uverbs_attr_bundle.
676 *
677 * If udata is not NULL this cannot fail. Otherwise a NULL udata will result
678 * in a NULL ucontext pointer, as a safety precaution. Callers should be using
679 * 'udata' to determine if the driver call is in user or kernel mode, not
680 * 'ucontext'.
681 *
682 */
683static inline struct uverbs_attr_bundle *
684rdma_udata_to_uverbs_attr_bundle(struct ib_udata *udata)
685{
686 return container_of(udata, struct uverbs_attr_bundle, driver_udata);
687}
688
689#define rdma_udata_to_drv_context(udata, drv_dev_struct, member) \
690 (udata ? container_of(rdma_udata_to_uverbs_attr_bundle(udata)->context, \
691 drv_dev_struct, member) : (drv_dev_struct *)NULL)
692
693#define IS_UVERBS_COPY_ERR(_ret) ((_ret) && (_ret) != -ENOENT)
694
695static inline const struct uverbs_attr *uverbs_attr_get(const struct uverbs_attr_bundle *attrs_bundle,
696 u16 idx)
697{
698 if (!uverbs_attr_is_valid(attrs_bundle, idx))
699 return ERR_PTR(-ENOENT);
700
701 return &attrs_bundle->attrs[uapi_bkey_attr(uapi_key_attr(idx))];
702}
703
704static inline int uverbs_attr_get_enum_id(const struct uverbs_attr_bundle *attrs_bundle,
705 u16 idx)
706{
707 const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
708
709 if (IS_ERR(attr))
710 return PTR_ERR(attr);
711
712 return attr->ptr_attr.enum_id;
713}
714
715static inline void *uverbs_attr_get_obj(const struct uverbs_attr_bundle *attrs_bundle,
716 u16 idx)
717{
718 const struct uverbs_attr *attr;
719
720 attr = uverbs_attr_get(attrs_bundle, idx);
721 if (IS_ERR(attr))
722 return ERR_CAST(attr);
723
724 return attr->obj_attr.uobject->object;
725}
726
727static inline struct ib_uobject *uverbs_attr_get_uobject(const struct uverbs_attr_bundle *attrs_bundle,
728 u16 idx)
729{
730 const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
731
732 if (IS_ERR(attr))
733 return ERR_CAST(attr);
734
735 return attr->obj_attr.uobject;
736}
737
738static inline int
739uverbs_attr_get_len(const struct uverbs_attr_bundle *attrs_bundle, u16 idx)
740{
741 const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
742
743 if (IS_ERR(attr))
744 return PTR_ERR(attr);
745
746 return attr->ptr_attr.len;
747}
748
749void uverbs_finalize_uobj_create(const struct uverbs_attr_bundle *attrs_bundle,
750 u16 idx);
751
752/*
753 * uverbs_attr_ptr_get_array_size() - Get array size pointer by a ptr
754 * attribute.
755 * @attrs: The attribute bundle
756 * @idx: The ID of the attribute
757 * @elem_size: The size of the element in the array
758 */
759static inline int
760uverbs_attr_ptr_get_array_size(struct uverbs_attr_bundle *attrs, u16 idx,
761 size_t elem_size)
762{
763 int size = uverbs_attr_get_len(attrs, idx);
764
765 if (size < 0)
766 return size;
767
768 if (size % elem_size)
769 return -EINVAL;
770
771 return size / elem_size;
772}
773
774/**
775 * uverbs_attr_get_uobjs_arr() - Provides array's properties for attribute for
776 * UVERBS_ATTR_TYPE_IDRS_ARRAY.
777 * @arr: Returned pointer to array of pointers for uobjects or NULL if
778 * the attribute isn't provided.
779 *
780 * Return: The array length or 0 if no attribute was provided.
781 */
782static inline int uverbs_attr_get_uobjs_arr(
783 const struct uverbs_attr_bundle *attrs_bundle, u16 attr_idx,
784 struct ib_uobject ***arr)
785{
786 const struct uverbs_attr *attr =
787 uverbs_attr_get(attrs_bundle, attr_idx);
788
789 if (IS_ERR(attr)) {
790 *arr = NULL;
791 return 0;
792 }
793
794 *arr = attr->objs_arr_attr.uobjects;
795
796 return attr->objs_arr_attr.len;
797}
798
799static inline bool uverbs_attr_ptr_is_inline(const struct uverbs_attr *attr)
800{
801 return attr->ptr_attr.len <= sizeof(attr->ptr_attr.data);
802}
803
804static inline void *uverbs_attr_get_alloced_ptr(
805 const struct uverbs_attr_bundle *attrs_bundle, u16 idx)
806{
807 const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
808
809 if (IS_ERR(attr))
810 return (void *)attr;
811
812 return uverbs_attr_ptr_is_inline(attr) ? (void *)&attr->ptr_attr.data :
813 attr->ptr_attr.ptr;
814}
815
816static inline int _uverbs_copy_from(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
823 if (IS_ERR(attr))
824 return PTR_ERR(attr);
825
826 /*
827 * Validation ensures attr->ptr_attr.len >= size. If the caller is
828 * using UVERBS_ATTR_SPEC_F_MIN_SZ_OR_ZERO then it must call
829 * uverbs_copy_from_or_zero.
830 */
831 if (unlikely(size < attr->ptr_attr.len))
832 return -EINVAL;
833
834 if (uverbs_attr_ptr_is_inline(attr))
835 memcpy(to, &attr->ptr_attr.data, attr->ptr_attr.len);
836 else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
837 attr->ptr_attr.len))
838 return -EFAULT;
839
840 return 0;
841}
842
843static inline int _uverbs_copy_from_or_zero(void *to,
844 const struct uverbs_attr_bundle *attrs_bundle,
845 size_t idx,
846 size_t size)
847{
848 const struct uverbs_attr *attr = uverbs_attr_get(attrs_bundle, idx);
849 size_t min_size;
850
851 if (IS_ERR(attr))
852 return PTR_ERR(attr);
853
854 min_size = min_t(size_t, size, attr->ptr_attr.len);
855
856 if (uverbs_attr_ptr_is_inline(attr))
857 memcpy(to, &attr->ptr_attr.data, min_size);
858 else if (copy_from_user(to, u64_to_user_ptr(attr->ptr_attr.data),
859 min_size))
860 return -EFAULT;
861
862 if (size > min_size)
863 memset(to + min_size, 0, size - min_size);
864
865 return 0;
866}
867
868#define uverbs_copy_from(to, attrs_bundle, idx) \
869 _uverbs_copy_from(to, attrs_bundle, idx, sizeof(*to))
870
871#define uverbs_copy_from_or_zero(to, attrs_bundle, idx) \
872 _uverbs_copy_from_or_zero(to, attrs_bundle, idx, sizeof(*to))
873
874static inline struct ib_ucontext *
875ib_uverbs_get_ucontext(const struct uverbs_attr_bundle *attrs)
876{
877 return ib_uverbs_get_ucontext_file(attrs->ufile);
878}
879
880#if IS_ENABLED(CONFIG_INFINIBAND_USER_ACCESS)
881int uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle,
882 size_t idx, u64 allowed_bits);
883int uverbs_get_flags32(u32 *to, const struct uverbs_attr_bundle *attrs_bundle,
884 size_t idx, u64 allowed_bits);
885int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle, size_t idx,
886 const void *from, size_t size);
887int uverbs_get_buffer_desc(const struct uverbs_attr_bundle *attrs_bundle,
888 u16 attr_id, struct ib_uverbs_buffer_desc *desc);
889__malloc void *_uverbs_alloc(struct uverbs_attr_bundle *bundle, size_t size,
890 gfp_t flags);
891
892static inline __malloc void *uverbs_alloc(struct uverbs_attr_bundle *bundle,
893 size_t size)
894{
895 return _uverbs_alloc(bundle, size, GFP_KERNEL);
896}
897
898static inline __malloc void *uverbs_zalloc(struct uverbs_attr_bundle *bundle,
899 size_t size)
900{
901 return _uverbs_alloc(bundle, size, GFP_KERNEL | __GFP_ZERO);
902}
903
904static inline __malloc void *uverbs_kcalloc(struct uverbs_attr_bundle *bundle,
905 size_t n, size_t size)
906{
907 size_t bytes;
908
909 if (unlikely(check_mul_overflow(n, size, &bytes)))
910 return ERR_PTR(-EOVERFLOW);
911 return uverbs_zalloc(bundle, bytes);
912}
913
914int _uverbs_get_const_signed(s64 *to,
915 const struct uverbs_attr_bundle *attrs_bundle,
916 size_t idx, s64 lower_bound, u64 upper_bound,
917 s64 *def_val);
918int _uverbs_get_const_unsigned(u64 *to,
919 const struct uverbs_attr_bundle *attrs_bundle,
920 size_t idx, u64 upper_bound, u64 *def_val);
921int uverbs_copy_to_struct_or_zero(const struct uverbs_attr_bundle *bundle,
922 size_t idx, const void *from, size_t size);
923
924int _ib_copy_validate_udata_in(struct ib_udata *udata, void *req,
925 size_t kernel_size, size_t minimum_size);
926int _ib_respond_udata(struct ib_udata *udata, const void *src, size_t len);
927int _ib_copy_validate_udata_cm_fail(struct ib_udata *udata, u64 req_cm,
928 u64 valid_cm);
929#else
930static inline int
931uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle,
932 size_t idx, u64 allowed_bits)
933{
934 return -EINVAL;
935}
936static inline int
937uverbs_get_flags32(u32 *to, const struct uverbs_attr_bundle *attrs_bundle,
938 size_t idx, u64 allowed_bits)
939{
940 return -EINVAL;
941}
942static inline int uverbs_copy_to(const struct uverbs_attr_bundle *attrs_bundle,
943 size_t idx, const void *from, size_t size)
944{
945 return -EINVAL;
946}
947static inline int
948uverbs_get_buffer_desc(const struct uverbs_attr_bundle *attrs_bundle,
949 u16 attr_id, struct ib_uverbs_buffer_desc *desc)
950{
951 return -EINVAL;
952}
953static inline __malloc void *uverbs_alloc(struct uverbs_attr_bundle *bundle,
954 size_t size)
955{
956 return ERR_PTR(-EINVAL);
957}
958static inline __malloc void *uverbs_zalloc(struct uverbs_attr_bundle *bundle,
959 size_t size)
960{
961 return ERR_PTR(-EINVAL);
962}
963static inline int
964_uverbs_get_const(s64 *to, const struct uverbs_attr_bundle *attrs_bundle,
965 size_t idx, s64 lower_bound, u64 upper_bound,
966 s64 *def_val)
967{
968 return -EINVAL;
969}
970static inline int
971uverbs_copy_to_struct_or_zero(const struct uverbs_attr_bundle *bundle,
972 size_t idx, const void *from, size_t size)
973{
974 return -EINVAL;
975}
976static inline int
977_uverbs_get_const_signed(s64 *to,
978 const struct uverbs_attr_bundle *attrs_bundle,
979 size_t idx, s64 lower_bound, u64 upper_bound,
980 s64 *def_val)
981{
982 return -EINVAL;
983}
984static inline int
985_uverbs_get_const_unsigned(u64 *to,
986 const struct uverbs_attr_bundle *attrs_bundle,
987 size_t idx, u64 upper_bound, u64 *def_val)
988{
989 return -EINVAL;
990}
991
992static inline int _ib_copy_validate_udata_in(struct ib_udata *udata, void *req,
993 size_t kernel_size,
994 size_t minimum_size)
995{
996 return -EINVAL;
997}
998
999static inline int _ib_respond_udata(struct ib_udata *udata, const void *src,
1000 size_t len)
1001{
1002 return -EINVAL;
1003}
1004
1005static inline int _ib_copy_validate_udata_cm_fail(struct ib_udata *udata,
1006 u64 req_cm, u64 valid_cm)
1007{
1008 return -EINVAL;
1009}
1010#endif
1011
1012#define uverbs_get_const_signed(_to, _attrs_bundle, _idx) \
1013 ({ \
1014 s64 _val; \
1015 int _ret = \
1016 _uverbs_get_const_signed(&_val, _attrs_bundle, _idx, \
1017 type_min(typeof(*(_to))), \
1018 type_max(typeof(*(_to))), NULL); \
1019 (*(_to)) = _val; \
1020 _ret; \
1021 })
1022
1023#define uverbs_get_const_unsigned(_to, _attrs_bundle, _idx) \
1024 ({ \
1025 u64 _val; \
1026 int _ret = \
1027 _uverbs_get_const_unsigned(&_val, _attrs_bundle, _idx, \
1028 type_max(typeof(*(_to))), NULL); \
1029 (*(_to)) = _val; \
1030 _ret; \
1031 })
1032
1033#define uverbs_get_const_default_signed(_to, _attrs_bundle, _idx, _default) \
1034 ({ \
1035 s64 _val; \
1036 s64 _def_val = _default; \
1037 int _ret = \
1038 _uverbs_get_const_signed(&_val, _attrs_bundle, _idx, \
1039 type_min(typeof(*(_to))), \
1040 type_max(typeof(*(_to))), &_def_val); \
1041 (*(_to)) = _val; \
1042 _ret; \
1043 })
1044
1045#define uverbs_get_const_default_unsigned(_to, _attrs_bundle, _idx, _default) \
1046 ({ \
1047 u64 _val; \
1048 u64 _def_val = _default; \
1049 int _ret = \
1050 _uverbs_get_const_unsigned(&_val, _attrs_bundle, _idx, \
1051 type_max(typeof(*(_to))), &_def_val); \
1052 (*(_to)) = _val; \
1053 _ret; \
1054 })
1055
1056#define uverbs_get_const(_to, _attrs_bundle, _idx) \
1057 (is_signed_type(typeof(*(_to))) ? \
1058 uverbs_get_const_signed(_to, _attrs_bundle, _idx) : \
1059 uverbs_get_const_unsigned(_to, _attrs_bundle, _idx)) \
1060
1061#define uverbs_get_const_default(_to, _attrs_bundle, _idx, _default) \
1062 (is_signed_type(typeof(*(_to))) ? \
1063 uverbs_get_const_default_signed(_to, _attrs_bundle, _idx, \
1064 _default) : \
1065 uverbs_get_const_default_unsigned(_to, _attrs_bundle, _idx, \
1066 _default))
1067
1068static inline int
1069uverbs_get_raw_fd(int *to, const struct uverbs_attr_bundle *attrs_bundle,
1070 size_t idx)
1071{
1072 return uverbs_get_const_signed(to, attrs_bundle, idx);
1073}
1074
1075/**
1076 * ib_copy_validate_udata_in - Copy and validate that the request structure is
1077 * compatible with this kernel
1078 * @_udata: The system calls ib_udata struct
1079 * @_req: The name of an on-stack structure that holds the driver data
1080 * @_end_member: The member in the struct that is the original end of struct
1081 * from the first kernel to introduce it.
1082 *
1083 * Check that the udata input request struct is properly formed for this kernel.
1084 * Then copy it into req
1085 */
1086#define ib_copy_validate_udata_in(_udata, _req, _end_member) \
1087 _ib_copy_validate_udata_in(_udata, &(_req), sizeof(_req), \
1088 offsetofend(typeof(_req), _end_member))
1089
1090/**
1091 * ib_copy_validate_udata_in_cm - Copy the req structure and check the comp_mask
1092 * @_udata: The system calls ib_udata struct
1093 * @_req: The name of an on-stack structure that holds the driver data
1094 * @_end_member: The member in the struct that is the original end of struct
1095 * from the first kernel to introduce it.
1096 * @_valid_cm: A bitmask of bits permitted in the comp_mask_field.
1097 *
1098 * Check that the udata input request struct is properly formed for this kernel.
1099 * Then copy it into req
1100 */
1101#define ib_copy_validate_udata_in_cm(_udata, _req, _end_member, _valid_cm) \
1102 ({ \
1103 typeof((_req).comp_mask) __valid_cm = _valid_cm; \
1104 int ret = \
1105 ib_copy_validate_udata_in(_udata, _req, _end_member); \
1106 if (!ret && ((_req).comp_mask & ~__valid_cm)) \
1107 ret = _ib_copy_validate_udata_cm_fail( \
1108 _udata, (_req).comp_mask, __valid_cm); \
1109 ret; \
1110 })
1111
1112/**
1113 * ib_is_udata_in_empty - Check if the udata input buffer is all zeros
1114 * @udata: The system calls ib_udata struct
1115 *
1116 * This should be used if the driver does not currently define a driver data
1117 * struct. Returns 0 if the buffer is empty or all zeros, -EOPNOTSUPP if
1118 * non-zero data is present, or a negative error code on failure.
1119 */
1120static inline int ib_is_udata_in_empty(struct ib_udata *udata)
1121{
1122 if (!udata || udata->inlen == 0)
1123 return 0;
1124 return _ib_copy_validate_udata_in(udata, NULL, 0, 0);
1125}
1126
1127/**
1128 * ib_respond_udata - Copy a driver data response to userspace
1129 * @_udata: The system calls ib_udata struct
1130 * @_rep: Kernel buffer containing the response driver data on the stack
1131 *
1132 * Copy driver data response structures back to userspace in a way that
1133 * is forwards and backwards compatible. Longer kernel structs are truncated,
1134 * userspace has made some kind of error if it needed the truncated information.
1135 * Shorter structs are zero padded.
1136 */
1137#define ib_respond_udata(_udata, _rep) \
1138 _ib_respond_udata(_udata, &(_rep), sizeof(_rep))
1139
1140/**
1141 * ib_respond_empty_udata - Zero fill the response buffer to userspace
1142 * @_udata: The system calls ib_udata struct
1143 *
1144 * Used when there is no driver response data to return. Provides forward
1145 * compatability by zeroing any buffer the user may have provided.
1146 */
1147static inline int ib_respond_empty_udata(struct ib_udata *udata)
1148{
1149 if (udata && udata->outlen && clear_user(udata->outbuf, udata->outlen))
1150 return -EFAULT;
1151 return 0;
1152}
1153
1154/**
1155 * ib_no_udata_io - Ensure no input data and zero fill the response buffer
1156 * @udata: The system call's ib_udata struct
1157 *
1158 * Driver ops which do not accept any input data and do not provide any response
1159 * data may call this at the beginning of their handler to fully adhere to the
1160 * uAPI forward/backward compatibility rules.
1161 *
1162 * Return: Negative failure code if the op should be denied, 0 otherwise.
1163 */
1164static inline int ib_no_udata_io(struct ib_udata *udata)
1165{
1166 int ret = ib_is_udata_in_empty(udata);
1167
1168 if (ret)
1169 return ret;
1170
1171 return ib_respond_empty_udata(udata);
1172}
1173
1174#endif