1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
|
/*
* Copyright(c) 2009 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*
* Maintained at www.Open-FCoE.org
*/
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/scatterlist.h>
#include <linux/crc32.h>
#include <scsi/libfc.h>
#include <scsi/fc_encode.h>
#include "fc_libfc.h"
MODULE_AUTHOR("Open-FCoE.org");
MODULE_DESCRIPTION("libfc");
MODULE_LICENSE("GPL v2");
unsigned int fc_debug_logging;
module_param_named(debug_logging, fc_debug_logging, int, S_IRUGO|S_IWUSR);
MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels");
/**
* libfc_init() - Initialize libfc.ko
*/
static int __init libfc_init(void)
{
int rc = 0;
rc = fc_setup_fcp();
if (rc)
return rc;
rc = fc_setup_exch_mgr();
if (rc)
goto destroy_pkt_cache;
rc = fc_setup_rport();
if (rc)
goto destroy_em;
return rc;
destroy_em:
fc_destroy_exch_mgr();
destroy_pkt_cache:
fc_destroy_fcp();
return rc;
}
module_init(libfc_init);
/**
* libfc_exit() - Tear down libfc.ko
*/
static void __exit libfc_exit(void)
{
fc_destroy_fcp();
fc_destroy_exch_mgr();
fc_destroy_rport();
}
module_exit(libfc_exit);
/**
* fc_copy_buffer_to_sglist() - This routine copies the data of a buffer
* into a scatter-gather list (SG list).
*
* @buf: pointer to the data buffer.
* @len: the byte-length of the data buffer.
* @sg: pointer to the pointer of the SG list.
* @nents: pointer to the remaining number of entries in the SG list.
* @offset: pointer to the current offset in the SG list.
* @km_type: dedicated page table slot type for kmap_atomic.
* @crc: pointer to the 32-bit crc value.
* If crc is NULL, CRC is not calculated.
*/
u32 fc_copy_buffer_to_sglist(void *buf, size_t len,
struct scatterlist *sg,
u32 *nents, size_t *offset,
enum km_type km_type, u32 *crc)
{
size_t remaining = len;
u32 copy_len = 0;
while (remaining > 0 && sg) {
size_t off, sg_bytes;
void *page_addr;
if (*offset >= sg->length) {
/*
* Check for end and drop resources
* from the last iteration.
*/
if (!(*nents))
break;
--(*nents);
*offset -= sg->length;
sg = sg_next(sg);
continue;
}
sg_bytes = min(remaining, sg->length - *offset);
/*
* The scatterlist item may be bigger than PAGE_SIZE,
* but we are limited to mapping PAGE_SIZE at a time.
*/
off = *offset + sg->offset;
sg_bytes = min(sg_bytes,
(size_t)(PAGE_SIZE - (off & ~PAGE_MASK)));
page_addr = kmap_atomic(sg_page(sg) + (off >> PAGE_SHIFT),
km_type);
if (crc)
*crc = crc32(*crc, buf, sg_bytes);
memcpy((char *)page_addr + (off & ~PAGE_MASK), buf, sg_bytes);
kunmap_atomic(page_addr, km_type);
buf += sg_bytes;
*offset += sg_bytes;
remaining -= sg_bytes;
copy_len += sg_bytes;
}
return copy_len;
}
/**
* fc_fill_hdr() - fill FC header fields based on request
* @fp: reply frame containing header to be filled in
* @in_fp: request frame containing header to use in filling in reply
* @r_ctl: R_CTL value for header
* @f_ctl: F_CTL value for header, with 0 pad
* @seq_cnt: sequence count for the header, ignored if frame has a sequence
* @parm_offset: parameter / offset value
*/
void fc_fill_hdr(struct fc_frame *fp, const struct fc_frame *in_fp,
enum fc_rctl r_ctl, u32 f_ctl, u16 seq_cnt, u32 parm_offset)
{
struct fc_frame_header *fh;
struct fc_frame_header *in_fh;
struct fc_seq *sp;
u32 fill;
fh = __fc_frame_header_get(fp);
in_fh = __fc_frame_header_get(in_fp);
if (f_ctl & FC_FC_END_SEQ) {
fill = -fr_len(fp) & 3;
if (fill) {
/* TODO, this may be a problem with fragmented skb */
memset(skb_put(fp_skb(fp), fill), 0, fill);
f_ctl |= fill;
}
fr_eof(fp) = FC_EOF_T;
} else {
WARN_ON(fr_len(fp) % 4 != 0); /* no pad to non last frame */
fr_eof(fp) = FC_EOF_N;
}
fh->fh_r_ctl = r_ctl;
memcpy(fh->fh_d_id, in_fh->fh_s_id, sizeof(fh->fh_d_id));
memcpy(fh->fh_s_id, in_fh->fh_d_id, sizeof(fh->fh_s_id));
fh->fh_type = in_fh->fh_type;
hton24(fh->fh_f_ctl, f_ctl);
fh->fh_ox_id = in_fh->fh_ox_id;
fh->fh_rx_id = in_fh->fh_rx_id;
fh->fh_cs_ctl = 0;
fh->fh_df_ctl = 0;
fh->fh_parm_offset = htonl(parm_offset);
sp = fr_seq(in_fp);
if (sp) {
fr_seq(fp) = sp;
fh->fh_seq_id = sp->id;
seq_cnt = sp->cnt;
} else {
fh->fh_seq_id = 0;
}
fh->fh_seq_cnt = ntohs(seq_cnt);
fr_sof(fp) = seq_cnt ? FC_SOF_N3 : FC_SOF_I3;
fr_encaps(fp) = fr_encaps(in_fp);
}
EXPORT_SYMBOL(fc_fill_hdr);
/**
* fc_fill_reply_hdr() - fill FC reply header fields based on request
* @fp: reply frame containing header to be filled in
* @in_fp: request frame containing header to use in filling in reply
* @r_ctl: R_CTL value for reply
* @parm_offset: parameter / offset value
*/
void fc_fill_reply_hdr(struct fc_frame *fp, const struct fc_frame *in_fp,
enum fc_rctl r_ctl, u32 parm_offset)
{
struct fc_seq *sp;
sp = fr_seq(in_fp);
if (sp)
fr_seq(fp) = fr_dev(in_fp)->tt.seq_start_next(sp);
fc_fill_hdr(fp, in_fp, r_ctl, FC_FCTL_RESP, 0, parm_offset);
}
EXPORT_SYMBOL(fc_fill_reply_hdr);
|
