1/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
2/*
3 * Copyright (c) 2020, Mellanox Technologies inc. All rights reserved.
4 */
5#ifndef _IBA_DEFS_H_
6#define _IBA_DEFS_H_
7
8#include <linux/kernel.h>
9#include <linux/bitfield.h>
10#include <asm/unaligned.h>
11
12static inline u32 _iba_get8(const u8 *ptr)
13{
14 return *ptr;
15}
16
17static inline void _iba_set8(u8 *ptr, u32 mask, u32 prep_value)
18{
19 *ptr = (*ptr & ~mask) | prep_value;
20}
21
22static inline u16 _iba_get16(const __be16 *ptr)
23{
24 return be16_to_cpu(*ptr);
25}
26
27static inline void _iba_set16(__be16 *ptr, u16 mask, u16 prep_value)
28{
29 *ptr = cpu_to_be16((be16_to_cpu(*ptr) & ~mask) | prep_value);
30}
31
32static inline u32 _iba_get32(const __be32 *ptr)
33{
34 return be32_to_cpu(*ptr);
35}
36
37static inline void _iba_set32(__be32 *ptr, u32 mask, u32 prep_value)
38{
39 *ptr = cpu_to_be32((be32_to_cpu(*ptr) & ~mask) | prep_value);
40}
41
42static inline u64 _iba_get64(const __be64 *ptr)
43{
44 /*
45 * The mads are constructed so that 32 bit and smaller are naturally
46 * aligned, everything larger has a max alignment of 4 bytes.
47 */
48 return be64_to_cpu(get_unaligned(ptr));
49}
50
51static inline void _iba_set64(__be64 *ptr, u64 mask, u64 prep_value)
52{
53 put_unaligned(cpu_to_be64((_iba_get64(ptr) & ~mask) | prep_value), ptr);
54}
55
56#define _IBA_SET(field_struct, field_offset, field_mask, num_bits, ptr, value) \
57 ({ \
58 field_struct *_ptr = ptr; \
59 _iba_set##num_bits((void *)_ptr + (field_offset), field_mask, \
60 FIELD_PREP(field_mask, value)); \
61 })
62#define IBA_SET(field, ptr, value) _IBA_SET(field, ptr, value)
63
64#define _IBA_GET_MEM_PTR(field_struct, field_offset, type, num_bits, ptr) \
65 ({ \
66 field_struct *_ptr = ptr; \
67 (type *)((void *)_ptr + (field_offset)); \
68 })
69#define IBA_GET_MEM_PTR(field, ptr) _IBA_GET_MEM_PTR(field, ptr)
70
71/* FIXME: A set should always set the entire field, meaning we should zero the trailing bytes */
72#define _IBA_SET_MEM(field_struct, field_offset, type, num_bits, ptr, in, \
73 bytes) \
74 ({ \
75 const type *_in_ptr = in; \
76 WARN_ON(bytes * 8 > num_bits); \
77 if (in && bytes) \
78 memcpy(_IBA_GET_MEM_PTR(field_struct, field_offset, \
79 type, num_bits, ptr), \
80 _in_ptr, bytes); \
81 })
82#define IBA_SET_MEM(field, ptr, in, bytes) _IBA_SET_MEM(field, ptr, in, bytes)
83
84#define _IBA_GET(field_struct, field_offset, field_mask, num_bits, ptr) \
85 ({ \
86 const field_struct *_ptr = ptr; \
87 (u##num_bits) FIELD_GET( \
88 field_mask, _iba_get##num_bits((const void *)_ptr + \
89 (field_offset))); \
90 })
91#define IBA_GET(field, ptr) _IBA_GET(field, ptr)
92
93#define _IBA_GET_MEM(field_struct, field_offset, type, num_bits, ptr, out, \
94 bytes) \
95 ({ \
96 type *_out_ptr = out; \
97 WARN_ON(bytes * 8 > num_bits); \
98 if (out && bytes) \
99 memcpy(_out_ptr, \
100 _IBA_GET_MEM_PTR(field_struct, field_offset, \
101 type, num_bits, ptr), \
102 bytes); \
103 })
104#define IBA_GET_MEM(field, ptr, out, bytes) _IBA_GET_MEM(field, ptr, out, bytes)
105
106/*
107 * The generated list becomes the parameters to the macros, the order is:
108 * - struct this applies to
109 * - starting offset of the max
110 * - GENMASK or GENMASK_ULL in CPU order
111 * - The width of data the mask operations should work on, in bits
112 */
113
114/*
115 * Extraction using a tabular description like table 106. bit_offset is from
116 * the Byte[Bit] notation.
117 */
118#define IBA_FIELD_BLOC(field_struct, byte_offset, bit_offset, num_bits) \
119 field_struct, byte_offset, \
120 GENMASK(7 - (bit_offset), 7 - (bit_offset) - (num_bits - 1)), \
121 8
122#define IBA_FIELD8_LOC(field_struct, byte_offset, num_bits) \
123 IBA_FIELD_BLOC(field_struct, byte_offset, 0, num_bits)
124
125#define IBA_FIELD16_LOC(field_struct, byte_offset, num_bits) \
126 field_struct, (byte_offset)&0xFFFE, \
127 GENMASK(15 - (((byte_offset) % 2) * 8), \
128 15 - (((byte_offset) % 2) * 8) - (num_bits - 1)), \
129 16
130
131#define IBA_FIELD32_LOC(field_struct, byte_offset, num_bits) \
132 field_struct, (byte_offset)&0xFFFC, \
133 GENMASK(31 - (((byte_offset) % 4) * 8), \
134 31 - (((byte_offset) % 4) * 8) - (num_bits - 1)), \
135 32
136
137#define IBA_FIELD64_LOC(field_struct, byte_offset) \
138 field_struct, byte_offset, GENMASK_ULL(63, 0), 64
139/*
140 * In IBTA spec, everything that is more than 64bits is multiple
141 * of bytes without leftover bits.
142 */
143#define IBA_FIELD_MLOC(field_struct, byte_offset, num_bits, type) \
144 field_struct, byte_offset, type, num_bits
145
146#endif /* _IBA_DEFS_H_ */
147

source code of linux/include/rdma/iba.h