Merge master.kernel.org:/pub/scm/linux/kernel/git/dtor/input
[linux-2.6] / drivers / infiniband / core / packer.c
1 /*
2  * Copyright (c) 2004 Topspin Corporation.  All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  *
32  * $Id: packer.c 1349 2004-12-16 21:09:43Z roland $
33  */
34
35 #include <ib_pack.h>
36
37 static u64 value_read(int offset, int size, void *structure)
38 {
39         switch (size) {
40         case 1: return                *(u8  *) (structure + offset);
41         case 2: return be16_to_cpup((__be16 *) (structure + offset));
42         case 4: return be32_to_cpup((__be32 *) (structure + offset));
43         case 8: return be64_to_cpup((__be64 *) (structure + offset));
44         default:
45                 printk(KERN_WARNING "Field size %d bits not handled\n", size * 8);
46                 return 0;
47         }
48 }
49
50 /**
51  * ib_pack - Pack a structure into a buffer
52  * @desc:Array of structure field descriptions
53  * @desc_len:Number of entries in @desc
54  * @structure:Structure to pack from
55  * @buf:Buffer to pack into
56  *
57  * ib_pack() packs a list of structure fields into a buffer,
58  * controlled by the array of fields in @desc.
59  */
60 void ib_pack(const struct ib_field        *desc,
61              int                           desc_len,
62              void                         *structure,
63              void                         *buf)
64 {
65         int i;
66
67         for (i = 0; i < desc_len; ++i) {
68                 if (desc[i].size_bits <= 32) {
69                         int shift;
70                         u32 val;
71                         __be32 mask;
72                         __be32 *addr;
73
74                         shift = 32 - desc[i].offset_bits - desc[i].size_bits;
75                         if (desc[i].struct_size_bytes)
76                                 val = value_read(desc[i].struct_offset_bytes,
77                                                  desc[i].struct_size_bytes,
78                                                  structure) << shift;
79                         else
80                                 val = 0;
81
82                         mask = cpu_to_be32(((1ull << desc[i].size_bits) - 1) << shift);
83                         addr = (__be32 *) buf + desc[i].offset_words;
84                         *addr = (*addr & ~mask) | (cpu_to_be32(val) & mask);
85                 } else if (desc[i].size_bits <= 64) {
86                         int shift;
87                         u64 val;
88                         __be64 mask;
89                         __be64 *addr;
90
91                         shift = 64 - desc[i].offset_bits - desc[i].size_bits;
92                         if (desc[i].struct_size_bytes)
93                                 val = value_read(desc[i].struct_offset_bytes,
94                                                  desc[i].struct_size_bytes,
95                                                  structure) << shift;
96                         else
97                                 val = 0;
98
99                         mask = cpu_to_be64((~0ull >> (64 - desc[i].size_bits)) << shift);
100                         addr = (__be64 *) ((__be32 *) buf + desc[i].offset_words);
101                         *addr = (*addr & ~mask) | (cpu_to_be64(val) & mask);
102                 } else {
103                         if (desc[i].offset_bits % 8 ||
104                             desc[i].size_bits   % 8) {
105                                 printk(KERN_WARNING "Structure field %s of size %d "
106                                        "bits is not byte-aligned\n",
107                                        desc[i].field_name, desc[i].size_bits);
108                         }
109
110                         if (desc[i].struct_size_bytes)
111                                 memcpy(buf + desc[i].offset_words * 4 +
112                                        desc[i].offset_bits / 8,
113                                        structure + desc[i].struct_offset_bytes,
114                                        desc[i].size_bits / 8);
115                         else
116                                 memset(buf + desc[i].offset_words * 4 +
117                                        desc[i].offset_bits / 8,
118                                        0,
119                                        desc[i].size_bits / 8);
120                 }
121         }
122 }
123 EXPORT_SYMBOL(ib_pack);
124
125 static void value_write(int offset, int size, u64 val, void *structure)
126 {
127         switch (size * 8) {
128         case 8:  *(    u8 *) (structure + offset) = val; break;
129         case 16: *(__be16 *) (structure + offset) = cpu_to_be16(val); break;
130         case 32: *(__be32 *) (structure + offset) = cpu_to_be32(val); break;
131         case 64: *(__be64 *) (structure + offset) = cpu_to_be64(val); break;
132         default:
133                 printk(KERN_WARNING "Field size %d bits not handled\n", size * 8);
134         }
135 }
136
137 /**
138  * ib_unpack - Unpack a buffer into a structure
139  * @desc:Array of structure field descriptions
140  * @desc_len:Number of entries in @desc
141  * @buf:Buffer to unpack from
142  * @structure:Structure to unpack into
143  *
144  * ib_pack() unpacks a list of structure fields from a buffer,
145  * controlled by the array of fields in @desc.
146  */
147 void ib_unpack(const struct ib_field        *desc,
148                int                           desc_len,
149                void                         *buf,
150                void                         *structure)
151 {
152         int i;
153
154         for (i = 0; i < desc_len; ++i) {
155                 if (!desc[i].struct_size_bytes)
156                         continue;
157
158                 if (desc[i].size_bits <= 32) {
159                         int shift;
160                         u32  val;
161                         u32  mask;
162                         __be32 *addr;
163
164                         shift = 32 - desc[i].offset_bits - desc[i].size_bits;
165                         mask = ((1ull << desc[i].size_bits) - 1) << shift;
166                         addr = (__be32 *) buf + desc[i].offset_words;
167                         val = (be32_to_cpup(addr) & mask) >> shift;
168                         value_write(desc[i].struct_offset_bytes,
169                                     desc[i].struct_size_bytes,
170                                     val,
171                                     structure);
172                 } else if (desc[i].size_bits <= 64) {
173                         int shift;
174                         u64  val;
175                         u64  mask;
176                         __be64 *addr;
177
178                         shift = 64 - desc[i].offset_bits - desc[i].size_bits;
179                         mask = (~0ull >> (64 - desc[i].size_bits)) << shift;
180                         addr = (__be64 *) buf + desc[i].offset_words;
181                         val = (be64_to_cpup(addr) & mask) >> shift;
182                         value_write(desc[i].struct_offset_bytes,
183                                     desc[i].struct_size_bytes,
184                                     val,
185                                     structure);
186                 } else {
187                         if (desc[i].offset_bits % 8 ||
188                             desc[i].size_bits   % 8) {
189                                 printk(KERN_WARNING "Structure field %s of size %d "
190                                        "bits is not byte-aligned\n",
191                                        desc[i].field_name, desc[i].size_bits);
192                         }
193
194                         memcpy(structure + desc[i].struct_offset_bytes,
195                                buf + desc[i].offset_words * 4 +
196                                desc[i].offset_bits / 8,
197                                desc[i].size_bits / 8);
198                 }
199         }
200 }
201 EXPORT_SYMBOL(ib_unpack);