Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland...
[linux-2.6.git] / drivers / infiniband / core / packer.c
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 static u64 value_read(int offset, int size, void *structure)
39 {
40         switch (size) {
41         case 1: return                *(u8  *) (structure + offset);
42         case 2: return be16_to_cpup((__be16 *) (structure + offset));
43         case 4: return be32_to_cpup((__be32 *) (structure + offset));
44         case 8: return be64_to_cpup((__be64 *) (structure + offset));
45         default:
46                 printk(KERN_WARNING "Field size %d bits not handled\n", size * 8);
47                 return 0;
48         }
49 }
50
51 /**
52  * ib_pack - Pack a structure into a buffer
53  * @desc:Array of structure field descriptions
54  * @desc_len:Number of entries in @desc
55  * @structure:Structure to pack from
56  * @buf:Buffer to pack into
57  *
58  * ib_pack() packs a list of structure fields into a buffer,
59  * controlled by the array of fields in @desc.
60  */
61 void ib_pack(const struct ib_field        *desc,
62              int                           desc_len,
63              void                         *structure,
64              void                         *buf)
65 {
66         int i;
67
68         for (i = 0; i < desc_len; ++i) {
69                 if (desc[i].size_bits <= 32) {
70                         int shift;
71                         u32 val;
72                         __be32 mask;
73                         __be32 *addr;
74
75                         shift = 32 - desc[i].offset_bits - desc[i].size_bits;
76                         if (desc[i].struct_size_bytes)
77                                 val = value_read(desc[i].struct_offset_bytes,
78                                                  desc[i].struct_size_bytes,
79                                                  structure) << shift;
80                         else
81                                 val = 0;
82
83                         mask = cpu_to_be32(((1ull << desc[i].size_bits) - 1) << shift);
84                         addr = (__be32 *) buf + desc[i].offset_words;
85                         *addr = (*addr & ~mask) | (cpu_to_be32(val) & mask);
86                 } else if (desc[i].size_bits <= 64) {
87                         int shift;
88                         u64 val;
89                         __be64 mask;
90                         __be64 *addr;
91
92                         shift = 64 - desc[i].offset_bits - desc[i].size_bits;
93                         if (desc[i].struct_size_bytes)
94                                 val = value_read(desc[i].struct_offset_bytes,
95                                                  desc[i].struct_size_bytes,
96                                                  structure) << shift;
97                         else
98                                 val = 0;
99
100                         mask = cpu_to_be64((~0ull >> (64 - desc[i].size_bits)) << shift);
101                         addr = (__be64 *) ((__be32 *) buf + desc[i].offset_words);
102                         *addr = (*addr & ~mask) | (cpu_to_be64(val) & mask);
103                 } else {
104                         if (desc[i].offset_bits % 8 ||
105                             desc[i].size_bits   % 8) {
106                                 printk(KERN_WARNING "Structure field %s of size %d "
107                                        "bits is not byte-aligned\n",
108                                        desc[i].field_name, desc[i].size_bits);
109                         }
110
111                         if (desc[i].struct_size_bytes)
112                                 memcpy(buf + desc[i].offset_words * 4 +
113                                        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 +
118                                        desc[i].offset_bits / 8,
119                                        0,
120                                        desc[i].size_bits / 8);
121                 }
122         }
123 }
124 EXPORT_SYMBOL(ib_pack);
125
126 static void value_write(int offset, int size, u64 val, void *structure)
127 {
128         switch (size * 8) {
129         case 8:  *(    u8 *) (structure + offset) = val; break;
130         case 16: *(__be16 *) (structure + offset) = cpu_to_be16(val); break;
131         case 32: *(__be32 *) (structure + offset) = cpu_to_be32(val); break;
132         case 64: *(__be64 *) (structure + offset) = cpu_to_be64(val); break;
133         default:
134                 printk(KERN_WARNING "Field size %d bits not handled\n", size * 8);
135         }
136 }
137
138 /**
139  * ib_unpack - Unpack a buffer into a structure
140  * @desc:Array of structure field descriptions
141  * @desc_len:Number of entries in @desc
142  * @buf:Buffer to unpack from
143  * @structure:Structure to unpack into
144  *
145  * ib_pack() unpacks a list of structure fields from a buffer,
146  * controlled by the array of fields in @desc.
147  */
148 void ib_unpack(const struct ib_field        *desc,
149                int                           desc_len,
150                void                         *buf,
151                void                         *structure)
152 {
153         int i;
154
155         for (i = 0; i < desc_len; ++i) {
156                 if (!desc[i].struct_size_bytes)
157                         continue;
158
159                 if (desc[i].size_bits <= 32) {
160                         int shift;
161                         u32  val;
162                         u32  mask;
163                         __be32 *addr;
164
165                         shift = 32 - desc[i].offset_bits - desc[i].size_bits;
166                         mask = ((1ull << desc[i].size_bits) - 1) << shift;
167                         addr = (__be32 *) buf + desc[i].offset_words;
168                         val = (be32_to_cpup(addr) & mask) >> shift;
169                         value_write(desc[i].struct_offset_bytes,
170                                     desc[i].struct_size_bytes,
171                                     val,
172                                     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,
184                                     desc[i].struct_size_bytes,
185                                     val,
186                                     structure);
187                 } else {
188                         if (desc[i].offset_bits % 8 ||
189                             desc[i].size_bits   % 8) {
190                                 printk(KERN_WARNING "Structure field %s of size %d "
191                                        "bits is not byte-aligned\n",
192                                        desc[i].field_name, desc[i].size_bits);
193                         }
194
195                         memcpy(structure + desc[i].struct_offset_bytes,
196                                buf + desc[i].offset_words * 4 +
197                                desc[i].offset_bits / 8,
198                                desc[i].size_bits / 8);
199                 }
200         }
201 }
202 EXPORT_SYMBOL(ib_unpack);