1/*
2 * Copyright (c) 2004 Topspin Corporation.  All rights reserved.
3 * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
4 *
5 * This software is available to you under a choice of one of two
6 * licenses.  You may choose to be licensed under the terms of the GNU
7 * General Public License (GPL) Version 2, available from the file
8 * COPYING in the main directory of this source tree, or the
9 * OpenIB.org BSD license below:
10 *
11 *     Redistribution and use in source and binary forms, with or
12 *     without modification, are permitted provided that the following
13 *     conditions are met:
14 *
15 *      - Redistributions of source code must retain the above
16 *        copyright notice, this list of conditions and the following
17 *        disclaimer.
18 *
19 *      - Redistributions in binary form must reproduce the above
20 *        copyright notice, this list of conditions and the following
21 *        disclaimer in the documentation and/or other materials
22 *        provided with the distribution.
23 *
24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31 * SOFTWARE.
32 */
33
34/*#include <linux/string.h>*/
35
36#include <rdma/ib_pack.h>
37
38#include <linux/module.h>
39
40#include <asm/byteorder.h>
41
42static u64 value_read(int offset, int size, void *structure) {
43	switch (size) {
44	case 1:
45		return *(u8 *) (structure + offset);
46	case 2:
47		return be16_to_cpup((__be16 *) (structure + offset));
48	case 4:
49		return be32_to_cpup((__be32 *) (structure + offset));
50	case 8:
51		return be64_to_cpup((__be64 *) (structure + offset));
52	default:
53		printf("Field size %d bits not handled\n", size * 8);
54		return 0;
55	}
56}
57
58/**
59 * ib_pack - Pack a structure into a buffer
60 * @desc:Array of structure field descriptions
61 * @desc_len:Number of entries in @desc
62 * @structure:Structure to pack from
63 * @buf:Buffer to pack into
64 *
65 * ib_pack() packs a list of structure fields into a buffer,
66 * controlled by the array of fields in @desc.
67 */
68void ib_pack(const struct ib_field *desc, int desc_len, void *structure,
69		void *buf) {
70	int i;
71
72	for (i = 0; i < desc_len; ++i) {
73		if (desc[i].size_bits <= 32) {
74			int shift;
75			u32 val;
76			__be32 mask;
77			__be32 *addr;
78
79			shift = 32 - desc[i].offset_bits - desc[i].size_bits;
80			if (desc[i].struct_size_bytes)
81				val = value_read(desc[i].struct_offset_bytes,
82						desc[i].struct_size_bytes, structure) << shift;
83			else
84				val = 0;
85
86			mask = cpu_to_be32(((1ull << desc[i].size_bits) - 1) << shift);
87			addr = (__be32 *) buf + desc[i].offset_words;
88			*addr = (*addr & ~mask) | (cpu_to_be32(val) & mask);
89		} else if (desc[i].size_bits <= 64) {
90			int shift;
91			u64 val;
92			__be64 mask;
93			__be64 *addr;
94
95			shift = 64 - desc[i].offset_bits - desc[i].size_bits;
96			if (desc[i].struct_size_bytes)
97				val = value_read(desc[i].struct_offset_bytes,
98						desc[i].struct_size_bytes, structure) << shift;
99			else
100				val = 0;
101
102			mask = cpu_to_be64((~0ull >> (64 - desc[i].size_bits)) << shift);
103			addr = (__be64 *) ((__be32 *) buf + desc[i].offset_words);
104			*addr = (*addr & ~mask) | (cpu_to_be64(val) & mask);
105		} else {
106			if (desc[i].offset_bits % 8 || desc[i].size_bits % 8) {
107				printf("Structure field %s of size %d "
108						"bits is not byte-aligned\n", desc[i].field_name,
109						desc[i].size_bits);
110			}
111
112			if (desc[i].struct_size_bytes)
113				memcpy(buf + desc[i].offset_words * 4 + desc[i].offset_bits / 8,
114						structure + desc[i].struct_offset_bytes,
115						desc[i].size_bits / 8);
116			else
117				memset(buf + desc[i].offset_words * 4 + desc[i].offset_bits / 8,
118						0, desc[i].size_bits / 8);
119		}
120	}
121}
122EXPORT_SYMBOL(ib_pack);
123
124static void value_write(int offset, int size, u64 val, void *structure) {
125	switch (size * 8) {
126	case 8:
127		*(u8 *) (structure + offset) = val;
128		break;
129	case 16:
130		*(__be16 *) (structure + offset) = cpu_to_be16(val);
131		break;
132	case 32:
133		*(__be32 *) (structure + offset) = cpu_to_be32(val);
134		break;
135	case 64:
136		*(__be64 *) (structure + offset) = cpu_to_be64(val);
137		break;
138	default:
139		printf("Field size %d bits not handled\n", size * 8);
140	}
141}
142
143/**
144 * ib_unpack - Unpack a buffer into a structure
145 * @desc:Array of structure field descriptions
146 * @desc_len:Number of entries in @desc
147 * @buf:Buffer to unpack from
148 * @structure:Structure to unpack into
149 *
150 * ib_pack() unpacks a list of structure fields from a buffer,
151 * controlled by the array of fields in @desc.
152 */
153void ib_unpack(const struct ib_field *desc, int desc_len, void *buf,
154		void *structure) {
155	int i;
156
157	for (i = 0; i < desc_len; ++i) {
158		if (!desc[i].struct_size_bytes)
159			continue;
160
161		if (desc[i].size_bits <= 32) {
162			int shift;
163			u32 val;
164			u32 mask;
165			__be32 *addr;
166
167			shift = 32 - desc[i].offset_bits - desc[i].size_bits;
168			mask = ((1ull << desc[i].size_bits) - 1) << shift;
169			addr = (__be32 *) buf + desc[i].offset_words;
170			val = (be32_to_cpup(addr) & mask) >> shift;
171			value_write(desc[i].struct_offset_bytes, desc[i].struct_size_bytes,
172					val, structure);
173		} else if (desc[i].size_bits <= 64) {
174			int shift;
175			u64 val;
176			u64 mask;
177			__be64 *addr;
178
179			shift = 64 - desc[i].offset_bits - desc[i].size_bits;
180			mask = (~0ull >> (64 - desc[i].size_bits)) << shift;
181			addr = (__be64 *) buf + desc[i].offset_words;
182			val = (be64_to_cpup(addr) & mask) >> shift;
183			value_write(desc[i].struct_offset_bytes, desc[i].struct_size_bytes,
184					val, structure);
185		} else {
186			if (desc[i].offset_bits % 8 || desc[i].size_bits % 8) {
187				printf("Structure field %s of size %d "
188						"bits is not byte-aligned\n", desc[i].field_name,
189						desc[i].size_bits);
190			}
191
192			memcpy(structure + desc[i].struct_offset_bytes,
193					buf + desc[i].offset_words * 4 + desc[i].offset_bits / 8,
194					desc[i].size_bits / 8);
195		}
196	}
197}
198EXPORT_SYMBOL(ib_unpack);
199