1 /* 2 * Copyright(c) 2009 Intel Corporation. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or modify it 5 * under the terms and conditions of the GNU General Public License, 6 * version 2, as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 11 * more details. 12 * 13 * You should have received a copy of the GNU General Public License along with 14 * this program; if not, write to the Free Software Foundation, Inc., 15 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. 16 * 17 * Maintained at www.Open-FCoE.org 18 */ 19 20 #include <linux/kernel.h> 21 #include <linux/types.h> 22 #include <linux/scatterlist.h> 23 #include <linux/crc32.h> 24 #include <linux/module.h> 25 26 #include <scsi/libfc.h> 27 #include <scsi/fc_encode.h> 28 29 #include "fc_libfc.h" 30 31 MODULE_AUTHOR("Open-FCoE.org"); 32 MODULE_DESCRIPTION("libfc"); 33 MODULE_LICENSE("GPL v2"); 34 35 unsigned int fc_debug_logging; 36 module_param_named(debug_logging, fc_debug_logging, int, S_IRUGO|S_IWUSR); 37 MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels"); 38 39 DEFINE_MUTEX(fc_prov_mutex); 40 static LIST_HEAD(fc_local_ports); 41 struct blocking_notifier_head fc_lport_notifier_head = 42 BLOCKING_NOTIFIER_INIT(fc_lport_notifier_head); 43 EXPORT_SYMBOL(fc_lport_notifier_head); 44 45 /* 46 * Providers which primarily send requests and PRLIs. 47 */ 48 struct fc4_prov *fc_active_prov[FC_FC4_PROV_SIZE] = { 49 [0] = &fc_rport_t0_prov, 50 [FC_TYPE_FCP] = &fc_rport_fcp_init, 51 }; 52 53 /* 54 * Providers which receive requests. 55 */ 56 struct fc4_prov *fc_passive_prov[FC_FC4_PROV_SIZE] = { 57 [FC_TYPE_ELS] = &fc_lport_els_prov, 58 }; 59 60 /** 61 * libfc_init() - Initialize libfc.ko 62 */ 63 static int __init libfc_init(void) 64 { 65 int rc = 0; 66 67 rc = fc_setup_fcp(); 68 if (rc) 69 return rc; 70 71 rc = fc_setup_exch_mgr(); 72 if (rc) 73 goto destroy_pkt_cache; 74 75 rc = fc_setup_rport(); 76 if (rc) 77 goto destroy_em; 78 79 return rc; 80 destroy_em: 81 fc_destroy_exch_mgr(); 82 destroy_pkt_cache: 83 fc_destroy_fcp(); 84 return rc; 85 } 86 module_init(libfc_init); 87 88 /** 89 * libfc_exit() - Tear down libfc.ko 90 */ 91 static void __exit libfc_exit(void) 92 { 93 fc_destroy_fcp(); 94 fc_destroy_exch_mgr(); 95 fc_destroy_rport(); 96 } 97 module_exit(libfc_exit); 98 99 /** 100 * fc_copy_buffer_to_sglist() - This routine copies the data of a buffer 101 * into a scatter-gather list (SG list). 102 * 103 * @buf: pointer to the data buffer. 104 * @len: the byte-length of the data buffer. 105 * @sg: pointer to the pointer of the SG list. 106 * @nents: pointer to the remaining number of entries in the SG list. 107 * @offset: pointer to the current offset in the SG list. 108 * @crc: pointer to the 32-bit crc value. 109 * If crc is NULL, CRC is not calculated. 110 */ 111 u32 fc_copy_buffer_to_sglist(void *buf, size_t len, 112 struct scatterlist *sg, 113 u32 *nents, size_t *offset, 114 u32 *crc) 115 { 116 size_t remaining = len; 117 u32 copy_len = 0; 118 119 while (remaining > 0 && sg) { 120 size_t off, sg_bytes; 121 void *page_addr; 122 123 if (*offset >= sg->length) { 124 /* 125 * Check for end and drop resources 126 * from the last iteration. 127 */ 128 if (!(*nents)) 129 break; 130 --(*nents); 131 *offset -= sg->length; 132 sg = sg_next(sg); 133 continue; 134 } 135 sg_bytes = min(remaining, sg->length - *offset); 136 137 /* 138 * The scatterlist item may be bigger than PAGE_SIZE, 139 * but we are limited to mapping PAGE_SIZE at a time. 140 */ 141 off = *offset + sg->offset; 142 sg_bytes = min(sg_bytes, 143 (size_t)(PAGE_SIZE - (off & ~PAGE_MASK))); 144 page_addr = kmap_atomic(sg_page(sg) + (off >> PAGE_SHIFT)); 145 if (crc) 146 *crc = crc32(*crc, buf, sg_bytes); 147 memcpy((char *)page_addr + (off & ~PAGE_MASK), buf, sg_bytes); 148 kunmap_atomic(page_addr); 149 buf += sg_bytes; 150 *offset += sg_bytes; 151 remaining -= sg_bytes; 152 copy_len += sg_bytes; 153 } 154 return copy_len; 155 } 156 157 /** 158 * fc_fill_hdr() - fill FC header fields based on request 159 * @fp: reply frame containing header to be filled in 160 * @in_fp: request frame containing header to use in filling in reply 161 * @r_ctl: R_CTL value for header 162 * @f_ctl: F_CTL value for header, with 0 pad 163 * @seq_cnt: sequence count for the header, ignored if frame has a sequence 164 * @parm_offset: parameter / offset value 165 */ 166 void fc_fill_hdr(struct fc_frame *fp, const struct fc_frame *in_fp, 167 enum fc_rctl r_ctl, u32 f_ctl, u16 seq_cnt, u32 parm_offset) 168 { 169 struct fc_frame_header *fh; 170 struct fc_frame_header *in_fh; 171 struct fc_seq *sp; 172 u32 fill; 173 174 fh = __fc_frame_header_get(fp); 175 in_fh = __fc_frame_header_get(in_fp); 176 177 if (f_ctl & FC_FC_END_SEQ) { 178 fill = -fr_len(fp) & 3; 179 if (fill) { 180 /* TODO, this may be a problem with fragmented skb */ 181 memset(skb_put(fp_skb(fp), fill), 0, fill); 182 f_ctl |= fill; 183 } 184 fr_eof(fp) = FC_EOF_T; 185 } else { 186 WARN_ON(fr_len(fp) % 4 != 0); /* no pad to non last frame */ 187 fr_eof(fp) = FC_EOF_N; 188 } 189 190 fh->fh_r_ctl = r_ctl; 191 memcpy(fh->fh_d_id, in_fh->fh_s_id, sizeof(fh->fh_d_id)); 192 memcpy(fh->fh_s_id, in_fh->fh_d_id, sizeof(fh->fh_s_id)); 193 fh->fh_type = in_fh->fh_type; 194 hton24(fh->fh_f_ctl, f_ctl); 195 fh->fh_ox_id = in_fh->fh_ox_id; 196 fh->fh_rx_id = in_fh->fh_rx_id; 197 fh->fh_cs_ctl = 0; 198 fh->fh_df_ctl = 0; 199 fh->fh_parm_offset = htonl(parm_offset); 200 201 sp = fr_seq(in_fp); 202 if (sp) { 203 fr_seq(fp) = sp; 204 fh->fh_seq_id = sp->id; 205 seq_cnt = sp->cnt; 206 } else { 207 fh->fh_seq_id = 0; 208 } 209 fh->fh_seq_cnt = ntohs(seq_cnt); 210 fr_sof(fp) = seq_cnt ? FC_SOF_N3 : FC_SOF_I3; 211 fr_encaps(fp) = fr_encaps(in_fp); 212 } 213 EXPORT_SYMBOL(fc_fill_hdr); 214 215 /** 216 * fc_fill_reply_hdr() - fill FC reply header fields based on request 217 * @fp: reply frame containing header to be filled in 218 * @in_fp: request frame containing header to use in filling in reply 219 * @r_ctl: R_CTL value for reply 220 * @parm_offset: parameter / offset value 221 */ 222 void fc_fill_reply_hdr(struct fc_frame *fp, const struct fc_frame *in_fp, 223 enum fc_rctl r_ctl, u32 parm_offset) 224 { 225 struct fc_seq *sp; 226 227 sp = fr_seq(in_fp); 228 if (sp) 229 fr_seq(fp) = fr_dev(in_fp)->tt.seq_start_next(sp); 230 fc_fill_hdr(fp, in_fp, r_ctl, FC_FCTL_RESP, 0, parm_offset); 231 } 232 EXPORT_SYMBOL(fc_fill_reply_hdr); 233 234 /** 235 * fc_fc4_conf_lport_params() - Modify "service_params" of specified lport 236 * if there is service provider (target provider) registered with libfc 237 * for specified "fc_ft_type" 238 * @lport: Local port which service_params needs to be modified 239 * @type: FC-4 type, such as FC_TYPE_FCP 240 */ 241 void fc_fc4_conf_lport_params(struct fc_lport *lport, enum fc_fh_type type) 242 { 243 struct fc4_prov *prov_entry; 244 BUG_ON(type >= FC_FC4_PROV_SIZE); 245 BUG_ON(!lport); 246 prov_entry = fc_passive_prov[type]; 247 if (type == FC_TYPE_FCP) { 248 if (prov_entry && prov_entry->recv) 249 lport->service_params |= FCP_SPPF_TARG_FCN; 250 } 251 } 252 253 void fc_lport_iterate(void (*notify)(struct fc_lport *, void *), void *arg) 254 { 255 struct fc_lport *lport; 256 257 mutex_lock(&fc_prov_mutex); 258 list_for_each_entry(lport, &fc_local_ports, lport_list) 259 notify(lport, arg); 260 mutex_unlock(&fc_prov_mutex); 261 } 262 EXPORT_SYMBOL(fc_lport_iterate); 263 264 /** 265 * fc_fc4_register_provider() - register FC-4 upper-level provider. 266 * @type: FC-4 type, such as FC_TYPE_FCP 267 * @prov: structure describing provider including ops vector. 268 * 269 * Returns 0 on success, negative error otherwise. 270 */ 271 int fc_fc4_register_provider(enum fc_fh_type type, struct fc4_prov *prov) 272 { 273 struct fc4_prov **prov_entry; 274 int ret = 0; 275 276 if (type >= FC_FC4_PROV_SIZE) 277 return -EINVAL; 278 mutex_lock(&fc_prov_mutex); 279 prov_entry = (prov->recv ? fc_passive_prov : fc_active_prov) + type; 280 if (*prov_entry) 281 ret = -EBUSY; 282 else 283 *prov_entry = prov; 284 mutex_unlock(&fc_prov_mutex); 285 return ret; 286 } 287 EXPORT_SYMBOL(fc_fc4_register_provider); 288 289 /** 290 * fc_fc4_deregister_provider() - deregister FC-4 upper-level provider. 291 * @type: FC-4 type, such as FC_TYPE_FCP 292 * @prov: structure describing provider including ops vector. 293 */ 294 void fc_fc4_deregister_provider(enum fc_fh_type type, struct fc4_prov *prov) 295 { 296 BUG_ON(type >= FC_FC4_PROV_SIZE); 297 mutex_lock(&fc_prov_mutex); 298 if (prov->recv) 299 RCU_INIT_POINTER(fc_passive_prov[type], NULL); 300 else 301 RCU_INIT_POINTER(fc_active_prov[type], NULL); 302 mutex_unlock(&fc_prov_mutex); 303 synchronize_rcu(); 304 } 305 EXPORT_SYMBOL(fc_fc4_deregister_provider); 306 307 /** 308 * fc_fc4_add_lport() - add new local port to list and run notifiers. 309 * @lport: The new local port. 310 */ 311 void fc_fc4_add_lport(struct fc_lport *lport) 312 { 313 mutex_lock(&fc_prov_mutex); 314 list_add_tail(&lport->lport_list, &fc_local_ports); 315 blocking_notifier_call_chain(&fc_lport_notifier_head, 316 FC_LPORT_EV_ADD, lport); 317 mutex_unlock(&fc_prov_mutex); 318 } 319 320 /** 321 * fc_fc4_del_lport() - remove local port from list and run notifiers. 322 * @lport: The new local port. 323 */ 324 void fc_fc4_del_lport(struct fc_lport *lport) 325 { 326 mutex_lock(&fc_prov_mutex); 327 list_del(&lport->lport_list); 328 blocking_notifier_call_chain(&fc_lport_notifier_head, 329 FC_LPORT_EV_DEL, lport); 330 mutex_unlock(&fc_prov_mutex); 331 } 332