aboutsummaryrefslogtreecommitdiffstats
path: root/include/rdma/uverbs_ioctl.h
blob: 28570ac2b6a02a846ecd097c610d0d3d9fbd5352 (plain) (blame)
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
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
/*
 * 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,
	UVERBS_ATTR_TYPE_IDRS_ARRAY,
};

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;
	/* True if this is from UVERBS_ATTR_UHW */
	u8 is_udata: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 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;

		struct {
			/*
			 * higher bits mean the namespace and lower bits mean
			 * the type id within the namespace.
			 */
			u16				obj_type;
			u16				min_len;
			u16				max_len;
			u8				access;
		} objs_arr;
	} 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.
 *
 * This also encodes the tables for the write() and write() extended commands
 * using the coding
 *   OBJ_ID,UVERBS_API_METHOD_IS_WRITE,command #
 *   OBJ_ID,UVERBS_API_METHOD_IS_WRITE_EX,command_ex #
 * ie the WRITE path is treated as a special method type in the ioctl
 * framework.
 */
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_WRITE_KEY_NUM = 1 << UVERBS_API_ATTR_KEY_BITS,

	UVERBS_API_METHOD_KEY_BITS = 5,
	UVERBS_API_METHOD_KEY_SHIFT = UVERBS_API_ATTR_KEY_BITS,
	UVERBS_API_METHOD_KEY_NUM_CORE = 22,
	UVERBS_API_METHOD_IS_WRITE = 30 << UVERBS_API_METHOD_KEY_SHIFT,
	UVERBS_API_METHOD_IS_WRITE_EX = 31 << UVERBS_API_METHOD_KEY_SHIFT,
	UVERBS_API_METHOD_KEY_NUM_DRIVER =
		(UVERBS_API_METHOD_IS_WRITE >> UVERBS_API_METHOD_KEY_SHIFT) -
		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_write_method(u32 id)
{
	if (id >= UVERBS_API_WRITE_KEY_NUM)
		return UVERBS_API_KEY_ERR;
	return UVERBS_API_METHOD_IS_WRITE | id;
}

static inline __attribute_const__ u32 uapi_key_write_ex_method(u32 id)
{
	if (id >= UVERBS_API_WRITE_KEY_NUM)
		return UVERBS_API_KEY_ERR;
	return UVERBS_API_METHOD_IS_WRITE_EX | id;
}

static inline __attribute_const__ u32
uapi_key_attr_to_ioctl_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)
{
	unsigned int method = key & UVERBS_API_METHOD_KEY_MASK;

	return method != 0 && method < UVERBS_API_METHOD_IS_WRITE &&
	       (key & UVERBS_API_ATTR_KEY_MASK) == 0;
}

static inline __attribute_const__ bool uapi_key_is_write_method(u32 key)
{
	return (key & UVERBS_API_METHOD_KEY_MASK) == UVERBS_API_METHOD_IS_WRITE;
}

static inline __attribute_const__ bool uapi_key_is_write_ex_method(u32 key)
{
	return (key & UVERBS_API_METHOD_KEY_MASK) ==
	       UVERBS_API_METHOD_IS_WRITE_EX;
}

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;
}

/* Only true for ioctl methods */
static inline __attribute_const__ bool uapi_key_is_attr(u32 key)
{
	unsigned int method = key & UVERBS_API_METHOD_KEY_MASK;

	return method != 0 && method < UVERBS_API_METHOD_IS_WRITE &&
	       (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;
}

static inline __attribute_const__ u32 uapi_bkey_to_key_attr(u32 attr_bkey)
{
	return attr_bkey + 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 uverbs_attr_bundle *attrs);
};

struct uverbs_object_def {
	u16					 id;
	const struct uverbs_obj_type	        *type_attrs;
	size_t				         num_methods;
	const struct uverbs_method_def * const (*methods)[];
};

enum uapi_definition_kind {
	UAPI_DEF_END = 0,
	UAPI_DEF_OBJECT_START,
	UAPI_DEF_WRITE,
	UAPI_DEF_CHAIN_OBJ_TREE,
	UAPI_DEF_CHAIN,
	UAPI_DEF_IS_SUPPORTED_FUNC,
	UAPI_DEF_IS_SUPPORTED_DEV_FN,
};

enum uapi_definition_scope {
	UAPI_SCOPE_OBJECT = 1,
	UAPI_SCOPE_METHOD = 2,
};

struct uapi_definition {
	u8 kind;
	u8 scope;
	union {
		struct {
			u16 object_id;
		} object_start;
		struct {
			u16 command_num;
			u8 is_ex:1;
			u8 has_udata:1;
			u8 has_resp:1;
			u8 req_size;
			u8 resp_size;
		} write;
	};

	union {
		bool (*func_is_supported)(struct ib_device *device);
		int (*func_write)(struct uverbs_attr_bundle *attrs);
		const struct uapi_definition *chain;
		const struct uverbs_object_def *chain_obj_tree;
		size_t needs_fn_offset;
	};
};

/* Define things connected to object_id */
#define DECLARE_UVERBS_OBJECT(_object_id, ...)                                 \
	{                                                                      \
		.kind = UAPI_DEF_OBJECT_START,                                 \
		.object_start = { .object_id = _object_id },                   \
	},                                                                     \
		##__VA_ARGS__

/* Use in a var_args of DECLARE_UVERBS_OBJECT */
#define DECLARE_UVERBS_WRITE(_command_num, _func, _cmd_desc, ...)              \
	{                                                                      \
		.kind = UAPI_DEF_WRITE,                                        \
		.scope = UAPI_SCOPE_OBJECT,                                    \
		.write = { .is_ex = 0, .command_num = _command_num },          \
		.func_write = _func,                                           \
		_cmd_desc,                                                     \
	},                                                                     \
		##__VA_ARGS__

/* Use in a var_args of DECLARE_UVERBS_OBJECT */
#define DECLARE_UVERBS_WRITE_EX(_command_num, _func, _cmd_desc, ...)           \
	{                                                                      \
		.kind = UAPI_DEF_WRITE,                                        \
		.scope = UAPI_SCOPE_OBJECT,                                    \
		.write = { .is_ex = 1, .command_num = _command_num },          \
		.func_write = _func,                                           \
		_cmd_desc,                                                     \
	},                                                                     \
		##__VA_ARGS__

/*
 * Object is only supported if the function pointer named ibdev_fn in struct
 * ib_device is not NULL.
 */
#define UAPI_DEF_OBJ_NEEDS_FN(ibdev_fn)                                        \
	{                                                                      \
		.kind = UAPI_DEF_IS_SUPPORTED_DEV_FN,                          \
		.scope = UAPI_SCOPE_OBJECT,                                    \
		.needs_fn_offset =                                             \
			offsetof(struct ib_device_ops, ibdev_fn) +             \
			BUILD_BUG_ON_ZERO(                                     \
			    sizeof(((struct ib_device_ops *)0)->ibdev_fn) !=   \
			    sizeof(void *)),				       \
	}

/*
 * Method is only supported if the function pointer named ibdev_fn in struct
 * ib_device is not NULL.
 */
#define UAPI_DEF_METHOD_NEEDS_FN(ibdev_fn)                                     \
	{                                                                      \
		.kind = UAPI_DEF_IS_SUPPORTED_DEV_FN,                          \
		.scope = UAPI_SCOPE_METHOD,                                    \
		.needs_fn_offset =                                             \
			offsetof(struct ib_device_ops, ibdev_fn) +             \
			BUILD_BUG_ON_ZERO(                                     \
			    sizeof(((struct ib_device_ops *)0)->ibdev_fn) !=   \
			    sizeof(void *)),                                   \
	}

/* Call a function to determine if the entire object is supported or not */
#define UAPI_DEF_IS_OBJ_SUPPORTED(_func)                                       \
	{                                                                      \
		.kind = UAPI_DEF_IS_SUPPORTED_FUNC,                            \
		.scope = UAPI_SCOPE_OBJECT, .func_is_supported = _func,        \
	}

/* Include another struct uapi_definition in this one */
#define UAPI_DEF_CHAIN(_def_var)                                               \
	{                                                                      \
		.kind = UAPI_DEF_CHAIN, .chain = _def_var,                     \
	}

/* Temporary until the tree base description is replaced */
#define UAPI_DEF_CHAIN_OBJ_TREE(_object_enum, _object_ptr, ...)                \
	{                                                                      \
		.kind = UAPI_DEF_CHAIN_OBJ_TREE,                               \
		.object_start = { .object_id = _object_enum },                 \
		.chain_obj_tree = _object_ptr,                                 \
	},								       \
		##__VA_ARGS__
#define UAPI_DEF_CHAIN_OBJ_TREE_NAMED(_object_enum, ...)                       \
	UAPI_DEF_CHAIN_OBJ_TREE(_object_enum, &UVERBS_OBJECT(_object_enum),    \
				##__VA_ARGS__)

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

/*
 * min_len must be bigger than 0 and _max_len must be smaller than 4095.  Only
 * READ\WRITE accesses are supported.
 */
#define UVERBS_ATTR_IDRS_ARR(_attr_id, _idr_type, _access, _min_len, _max_len, \
			     ...)                                              \
	(&(const struct uverbs_attr_def){                                      \
		.id = (_attr_id) +                                             \
		      BUILD_BUG_ON_ZERO((_min_len) == 0 ||                     \
					(_max_len) >                           \
						PAGE_SIZE / sizeof(void *) ||  \
					(_min_len) > (_max_len) ||             \
					(_access) == UVERBS_ACCESS_NEW ||      \
					(_access) == UVERBS_ACCESS_DESTROY),   \
		.attr = { .type = UVERBS_ATTR_TYPE_IDRS_ARRAY,                 \
			  .u2.objs_arr.obj_type = _idr_type,                   \
			  .u2.objs_arr.access = _access,                       \
			  .u2.objs_arr.min_len = _min_len,                     \
			  .u2.objs_arr.max_len = _max_len,                     \
			  __VA_ARGS__ } })

/*
 * Only for use with UVERBS_ATTR_IDR, allows any uobject type to be accepted,
 * the user must validate the type of the uobject instead.
 */
#define UVERBS_IDR_ANY_OBJECT 0xFFFF

#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 member in the enum _enum_type. */
#define UVERBS_ATTR_CONST_IN(_attr_id, _enum_type, ...)                        \
	UVERBS_ATTR_PTR_IN(                                                    \
		_attr_id,                                                      \
		UVERBS_ATTR_SIZE(                                              \
			sizeof(u64) + BUILD_BUG_ON_ZERO(!sizeof(_enum_type)),  \
			sizeof(u64)),                                          \
		__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,                                        \
			   .is_udata = 1),				       \
	UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_UHW_OUT,                               \
			    UVERBS_ATTR_MIN_SIZE(0),			       \
			    UA_OPTIONAL,                                       \
			    .is_udata = 1)

/* =================================================
 *              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_objs_arr_attr {
	struct ib_uobject **uobjects;
	u16 len;
};

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

struct uverbs_attr_bundle {
	struct ib_udata driver_udata;
	struct ib_udata ucore;
	struct ib_uverbs_file *ufile;
	struct ib_ucontext *context;
	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);
}

/**
 * rdma_udata_to_drv_context - Helper macro to get the driver's context out of
 *                             ib_udata which is embedded in uverbs_attr_bundle.
 *
 * If udata is not NULL this cannot fail. Otherwise a NULL udata will result
 * in a NULL ucontext pointer, as a safety precaution. Callers should be using
 * 'udata' to determine if the driver call is in user or kernel mode, not
 * 'ucontext'.
 *
 */
#define rdma_udata_to_drv_context(udata, drv_dev_struct, member)               \
	(udata ? container_of(container_of(udata, struct uverbs_attr_bundle,   \
					   driver_udata)                       \
				      ->context,                               \
			      drv_dev_struct, member) :                        \
		 (drv_dev_struct *)NULL)

#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;
}

/*
 * uverbs_attr_ptr_get_array_size() - Get array size pointer by a ptr
 * attribute.
 * @attrs: The attribute bundle
 * @idx: The ID of the attribute
 * @elem_size: The size of the element in the array
 */
static inline int
uverbs_attr_ptr_get_array_size(struct uverbs_attr_bundle *attrs, u16 idx,
			       size_t elem_size)
{
	int size = uverbs_attr_get_len(attrs, idx);

	if (size < 0)
		return size;

	if (size % elem_size)
		return -EINVAL;

	return size / elem_size;
}

/**
 * uverbs_attr_get_uobjs_arr() - Provides array's properties for attribute for
 * UVERBS_ATTR_TYPE_IDRS_ARRAY.
 * @arr: Returned pointer to array of pointers for uobjects or NULL if
 *       the attribute isn't provided.
 *
 * Return: The array length or 0 if no attribute was provided.
 */
static inline int uverbs_attr_get_uobjs_arr(
	const struct uverbs_attr_bundle *attrs_bundle, u16 attr_idx,
	struct ib_uobject ***arr)
{
	const struct uverbs_attr *attr =
			uverbs_attr_get(attrs_bundle, attr_idx);

	if (IS_ERR(attr)) {
		*arr = NULL;
		return 0;
	}

	*arr = attr->objs_arr_attr.uobjects;

	return attr->objs_arr_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))

static inline struct ib_ucontext *
ib_uverbs_get_ucontext(const struct uverbs_attr_bundle *attrs)
{
	return ib_uverbs_get_ucontext_file(attrs->ufile);
}

#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);
}
int _uverbs_get_const(s64 *to, const struct uverbs_attr_bundle *attrs_bundle,
		      size_t idx, s64 lower_bound, u64 upper_bound,
		      s64 *def_val);
int uverbs_copy_to_struct_or_zero(const struct uverbs_attr_bundle *bundle,
				  size_t idx, const void *from, size_t size);
#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);
}
static inline int
_uverbs_get_const(s64 *to, const struct uverbs_attr_bundle *attrs_bundle,
		  size_t idx, s64 lower_bound, u64 upper_bound,
		  s64 *def_val)
{
	return -EINVAL;
}
static inline int
uverbs_copy_to_struct_or_zero(const struct uverbs_attr_bundle *bundle,
			      size_t idx, const void *from, size_t size)
{
	return -EINVAL;
}
#endif

#define uverbs_get_const(_to, _attrs_bundle, _idx)                             \
	({                                                                     \
		s64 _val;                                                      \
		int _ret = _uverbs_get_const(&_val, _attrs_bundle, _idx,       \
					     type_min(typeof(*_to)),           \
					     type_max(typeof(*_to)), NULL);    \
		(*_to) = _val;                                                 \
		_ret;                                                          \
	})

#define uverbs_get_const_default(_to, _attrs_bundle, _idx, _default)           \
	({                                                                     \
		s64 _val;                                                      \
		s64 _def_val = _default;                                       \
		int _ret =                                                     \
			_uverbs_get_const(&_val, _attrs_bundle, _idx,          \
					  type_min(typeof(*_to)),              \
					  type_max(typeof(*_to)), &_def_val);  \
		(*_to) = _val;                                                 \
		_ret;                                                          \
	})
#endif