1/*-
2 * SPDX-License-Identifier: BSD-2-Clause OR GPL-2.0
3 *
4 * Copyright (c) 2004 Topspin Corporation.  All rights reserved.
5 * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
6 *
7 * This software is available to you under a choice of one of two
8 * licenses.  You may choose to be licensed under the terms of the GNU
9 * General Public License (GPL) Version 2, available from the file
10 * COPYING in the main directory of this source tree, or the
11 * OpenIB.org BSD license below:
12 *
13 *     Redistribution and use in source and binary forms, with or
14 *     without modification, are permitted provided that the following
15 *     conditions are met:
16 *
17 *      - Redistributions of source code must retain the above
18 *        copyright notice, this list of conditions and the following
19 *        disclaimer.
20 *
21 *      - Redistributions in binary form must reproduce the above
22 *        copyright notice, this list of conditions and the following
23 *        disclaimer in the documentation and/or other materials
24 *        provided with the distribution.
25 *
26 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
27 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
28 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
29 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
30 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
31 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
32 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
33 * SOFTWARE.
34 */
35
36#include <sys/cdefs.h>
37__FBSDID("$FreeBSD: stable/11/sys/ofed/drivers/infiniband/core/ib_packer.c 337096 2018-08-02 08:33:51Z hselasky $");
38
39#include <linux/string.h>
40
41#include <rdma/ib_pack.h>
42
43static u64 value_read(int offset, int size, void *structure)
44{
45	switch (size) {
46	case 1: return                *(u8  *) ((char *)structure + offset);
47	case 2: return be16_to_cpup((__be16 *) ((char *)structure + offset));
48	case 4: return be32_to_cpup((__be32 *) ((char *)structure + offset));
49	case 8: return be64_to_cpup((__be64 *) ((char *)structure + offset));
50	default:
51		pr_warn("Field size %d bits not handled\n", size * 8);
52		return 0;
53	}
54}
55
56/**
57 * ib_pack - Pack a structure into a buffer
58 * @desc:Array of structure field descriptions
59 * @desc_len:Number of entries in @desc
60 * @structure:Structure to pack from
61 * @buf:Buffer to pack into
62 *
63 * ib_pack() packs a list of structure fields into a buffer,
64 * controlled by the array of fields in @desc.
65 */
66void ib_pack(const struct ib_field        *desc,
67	     int                           desc_len,
68	     void                         *structure,
69	     void                         *buf)
70{
71	int i;
72
73	for (i = 0; i < desc_len; ++i) {
74		if (desc[i].size_bits <= 32) {
75			int shift;
76			u32 val;
77			__be32 mask;
78			__be32 *addr;
79
80			shift = 32 - desc[i].offset_bits - desc[i].size_bits;
81			if (desc[i].struct_size_bytes)
82				val = value_read(desc[i].struct_offset_bytes,
83						 desc[i].struct_size_bytes,
84						 structure) << shift;
85			else
86				val = 0;
87
88			mask = cpu_to_be32(((1ull << desc[i].size_bits) - 1) << shift);
89			addr = (__be32 *) buf + desc[i].offset_words;
90			*addr = (*addr & ~mask) | (cpu_to_be32(val) & mask);
91		} else if (desc[i].size_bits <= 64) {
92			int shift;
93			u64 val;
94			__be64 mask;
95			__be64 *addr;
96
97			shift = 64 - desc[i].offset_bits - desc[i].size_bits;
98			if (desc[i].struct_size_bytes)
99				val = value_read(desc[i].struct_offset_bytes,
100						 desc[i].struct_size_bytes,
101						 structure) << shift;
102			else
103				val = 0;
104
105			mask = cpu_to_be64((~0ull >> (64 - desc[i].size_bits)) << shift);
106			addr = (__be64 *) ((__be32 *) buf + desc[i].offset_words);
107			*addr = (*addr & ~mask) | (cpu_to_be64(val) & mask);
108		} else {
109			if (desc[i].offset_bits % 8 ||
110			    desc[i].size_bits   % 8) {
111				pr_warn("Structure field %s of size %d bits is not byte-aligned\n",
112					desc[i].field_name, desc[i].size_bits);
113			}
114
115			if (desc[i].struct_size_bytes)
116				memcpy((char *)buf + desc[i].offset_words * 4 +
117				       desc[i].offset_bits / 8,
118				       (char *)structure + desc[i].struct_offset_bytes,
119				       desc[i].size_bits / 8);
120			else
121				memset((char *)buf + desc[i].offset_words * 4 +
122				       desc[i].offset_bits / 8,
123				       0,
124				       desc[i].size_bits / 8);
125		}
126	}
127}
128EXPORT_SYMBOL(ib_pack);
129
130static void value_write(int offset, int size, u64 val, void *structure)
131{
132	switch (size * 8) {
133	case 8:  *(    u8 *) ((char *)structure + offset) = val; break;
134	case 16: *(__be16 *) ((char *)structure + offset) = cpu_to_be16(val); break;
135	case 32: *(__be32 *) ((char *)structure + offset) = cpu_to_be32(val); break;
136	case 64: *(__be64 *) ((char *)structure + offset) = cpu_to_be64(val); break;
137	default:
138		pr_warn("Field size %d bits not handled\n", size * 8);
139	}
140}
141
142/**
143 * ib_unpack - Unpack a buffer into a structure
144 * @desc:Array of structure field descriptions
145 * @desc_len:Number of entries in @desc
146 * @buf:Buffer to unpack from
147 * @structure:Structure to unpack into
148 *
149 * ib_pack() unpacks a list of structure fields from a buffer,
150 * controlled by the array of fields in @desc.
151 */
152void ib_unpack(const struct ib_field        *desc,
153	       int                           desc_len,
154	       void                         *buf,
155	       void                         *structure)
156{
157	int i;
158
159	for (i = 0; i < desc_len; ++i) {
160		if (!desc[i].struct_size_bytes)
161			continue;
162
163		if (desc[i].size_bits <= 32) {
164			int shift;
165			u32  val;
166			u32  mask;
167			__be32 *addr;
168
169			shift = 32 - desc[i].offset_bits - desc[i].size_bits;
170			mask = ((1ull << desc[i].size_bits) - 1) << shift;
171			addr = (__be32 *) buf + desc[i].offset_words;
172			val = (be32_to_cpup(addr) & mask) >> shift;
173			value_write(desc[i].struct_offset_bytes,
174				    desc[i].struct_size_bytes,
175				    val,
176				    structure);
177		} else if (desc[i].size_bits <= 64) {
178			int shift;
179			u64  val;
180			u64  mask;
181			__be64 *addr;
182
183			shift = 64 - desc[i].offset_bits - desc[i].size_bits;
184			mask = (~0ull >> (64 - desc[i].size_bits)) << shift;
185			addr = (__be64 *) buf + desc[i].offset_words;
186			val = (be64_to_cpup(addr) & mask) >> shift;
187			value_write(desc[i].struct_offset_bytes,
188				    desc[i].struct_size_bytes,
189				    val,
190				    structure);
191		} else {
192			if (desc[i].offset_bits % 8 ||
193			    desc[i].size_bits   % 8) {
194				pr_warn("Structure field %s of size %d bits is not byte-aligned\n",
195					desc[i].field_name, desc[i].size_bits);
196			}
197
198			memcpy((char *)structure + desc[i].struct_offset_bytes,
199			       (char *)buf + desc[i].offset_words * 4 +
200			       desc[i].offset_bits / 8,
201			       desc[i].size_bits / 8);
202		}
203	}
204}
205EXPORT_SYMBOL(ib_unpack);
206