1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright(c) 2009 Intel Corporation. All rights reserved. 4 * 5 * Maintained at www.Open-FCoE.org 6 */ 7 8 #include <linux/kernel.h> 9 #include <linux/types.h> 10 #include <linux/scatterlist.h> 11 #include <linux/crc32.h> 12 #include <linux/module.h> 13 14 #include <scsi/libfc.h> 15 #include <scsi/fc_encode.h> 16 17 #include "fc_libfc.h" 18 19 MODULE_AUTHOR("Open-FCoE.org"); 20 MODULE_DESCRIPTION("libfc"); 21 MODULE_LICENSE("GPL v2"); 22 23 unsigned int fc_debug_logging; 24 module_param_named(debug_logging, fc_debug_logging, int, S_IRUGO|S_IWUSR); 25 MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels"); 26 27 DEFINE_MUTEX(fc_prov_mutex); 28 static LIST_HEAD(fc_local_ports); 29 struct blocking_notifier_head fc_lport_notifier_head = 30 BLOCKING_NOTIFIER_INIT(fc_lport_notifier_head); 31 EXPORT_SYMBOL(fc_lport_notifier_head); 32 33 /* 34 * Providers which primarily send requests and PRLIs. 35 */ 36 struct fc4_prov *fc_active_prov[FC_FC4_PROV_SIZE] = { 37 [0] = &fc_rport_t0_prov, 38 [FC_TYPE_FCP] = &fc_rport_fcp_init, 39 }; 40 41 /* 42 * Providers which receive requests. 43 */ 44 struct fc4_prov *fc_passive_prov[FC_FC4_PROV_SIZE] = { 45 [FC_TYPE_ELS] = &fc_lport_els_prov, 46 }; 47 48 /** 49 * libfc_init() - Initialize libfc.ko 50 */ 51 static int __init libfc_init(void) 52 { 53 int rc = 0; 54 55 rc = fc_setup_fcp(); 56 if (rc) 57 return rc; 58 59 rc = fc_setup_exch_mgr(); 60 if (rc) 61 goto destroy_pkt_cache; 62 63 rc = fc_setup_rport(); 64 if (rc) 65 goto destroy_em; 66 67 return rc; 68 destroy_em: 69 fc_destroy_exch_mgr(); 70 destroy_pkt_cache: 71 fc_destroy_fcp(); 72 return rc; 73 } 74 module_init(libfc_init); 75 76 /** 77 * libfc_exit() - Tear down libfc.ko 78 */ 79 static void __exit libfc_exit(void) 80 { 81 fc_destroy_fcp(); 82 fc_destroy_exch_mgr(); 83 fc_destroy_rport(); 84 } 85 module_exit(libfc_exit); 86 87 /** 88 * fc_copy_buffer_to_sglist() - This routine copies the data of a buffer 89 * into a scatter-gather list (SG list). 90 * 91 * @buf: pointer to the data buffer. 92 * @len: the byte-length of the data buffer. 93 * @sg: pointer to the pointer of the SG list. 94 * @nents: pointer to the remaining number of entries in the SG list. 95 * @offset: pointer to the current offset in the SG list. 96 * @crc: pointer to the 32-bit crc value. 97 * If crc is NULL, CRC is not calculated. 98 */ 99 u32 fc_copy_buffer_to_sglist(void *buf, size_t len, 100 struct scatterlist *sg, 101 u32 *nents, size_t *offset, 102 u32 *crc) 103 { 104 size_t remaining = len; 105 u32 copy_len = 0; 106 107 while (remaining > 0 && sg) { 108 size_t off, sg_bytes; 109 void *page_addr; 110 111 if (*offset >= sg->length) { 112 /* 113 * Check for end and drop resources 114 * from the last iteration. 115 */ 116 if (!(*nents)) 117 break; 118 --(*nents); 119 *offset -= sg->length; 120 sg = sg_next(sg); 121 continue; 122 } 123 sg_bytes = min(remaining, sg->length - *offset); 124 125 /* 126 * The scatterlist item may be bigger than PAGE_SIZE, 127 * but we are limited to mapping PAGE_SIZE at a time. 128 */ 129 off = *offset + sg->offset; 130 sg_bytes = min(sg_bytes, 131 (size_t)(PAGE_SIZE - (off & ~PAGE_MASK))); 132 page_addr = kmap_atomic(sg_page(sg) + (off >> PAGE_SHIFT)); 133 if (crc) 134 *crc = crc32(*crc, buf, sg_bytes); 135 memcpy((char *)page_addr + (off & ~PAGE_MASK), buf, sg_bytes); 136 kunmap_atomic(page_addr); 137 buf += sg_bytes; 138 *offset += sg_bytes; 139 remaining -= sg_bytes; 140 copy_len += sg_bytes; 141 } 142 return copy_len; 143 } 144 145 /** 146 * fc_fill_hdr() - fill FC header fields based on request 147 * @fp: reply frame containing header to be filled in 148 * @in_fp: request frame containing header to use in filling in reply 149 * @r_ctl: R_CTL value for header 150 * @f_ctl: F_CTL value for header, with 0 pad 151 * @seq_cnt: sequence count for the header, ignored if frame has a sequence 152 * @parm_offset: parameter / offset value 153 */ 154 void fc_fill_hdr(struct fc_frame *fp, const struct fc_frame *in_fp, 155 enum fc_rctl r_ctl, u32 f_ctl, u16 seq_cnt, u32 parm_offset) 156 { 157 struct fc_frame_header *fh; 158 struct fc_frame_header *in_fh; 159 struct fc_seq *sp; 160 u32 fill; 161 162 fh = __fc_frame_header_get(fp); 163 in_fh = __fc_frame_header_get(in_fp); 164 165 if (f_ctl & FC_FC_END_SEQ) { 166 fill = -fr_len(fp) & 3; 167 if (fill) { 168 /* TODO, this may be a problem with fragmented skb */ 169 skb_put_zero(fp_skb(fp), fill); 170 f_ctl |= fill; 171 } 172 fr_eof(fp) = FC_EOF_T; 173 } else { 174 WARN_ON(fr_len(fp) % 4 != 0); /* no pad to non last frame */ 175 fr_eof(fp) = FC_EOF_N; 176 } 177 178 fh->fh_r_ctl = r_ctl; 179 memcpy(fh->fh_d_id, in_fh->fh_s_id, sizeof(fh->fh_d_id)); 180 memcpy(fh->fh_s_id, in_fh->fh_d_id, sizeof(fh->fh_s_id)); 181 fh->fh_type = in_fh->fh_type; 182 hton24(fh->fh_f_ctl, f_ctl); 183 fh->fh_ox_id = in_fh->fh_ox_id; 184 fh->fh_rx_id = in_fh->fh_rx_id; 185 fh->fh_cs_ctl = 0; 186 fh->fh_df_ctl = 0; 187 fh->fh_parm_offset = htonl(parm_offset); 188 189 sp = fr_seq(in_fp); 190 if (sp) { 191 fr_seq(fp) = sp; 192 fh->fh_seq_id = sp->id; 193 seq_cnt = sp->cnt; 194 } else { 195 fh->fh_seq_id = 0; 196 } 197 fh->fh_seq_cnt = ntohs(seq_cnt); 198 fr_sof(fp) = seq_cnt ? FC_SOF_N3 : FC_SOF_I3; 199 fr_encaps(fp) = fr_encaps(in_fp); 200 } 201 EXPORT_SYMBOL(fc_fill_hdr); 202 203 /** 204 * fc_fill_reply_hdr() - fill FC reply header fields based on request 205 * @fp: reply frame containing header to be filled in 206 * @in_fp: request frame containing header to use in filling in reply 207 * @r_ctl: R_CTL value for reply 208 * @parm_offset: parameter / offset value 209 */ 210 void fc_fill_reply_hdr(struct fc_frame *fp, const struct fc_frame *in_fp, 211 enum fc_rctl r_ctl, u32 parm_offset) 212 { 213 struct fc_seq *sp; 214 215 sp = fr_seq(in_fp); 216 if (sp) 217 fr_seq(fp) = fc_seq_start_next(sp); 218 fc_fill_hdr(fp, in_fp, r_ctl, FC_FCTL_RESP, 0, parm_offset); 219 } 220 EXPORT_SYMBOL(fc_fill_reply_hdr); 221 222 /** 223 * fc_fc4_conf_lport_params() - Modify "service_params" of specified lport 224 * if there is service provider (target provider) registered with libfc 225 * for specified "fc_ft_type" 226 * @lport: Local port which service_params needs to be modified 227 * @type: FC-4 type, such as FC_TYPE_FCP 228 */ 229 void fc_fc4_conf_lport_params(struct fc_lport *lport, enum fc_fh_type type) 230 { 231 struct fc4_prov *prov_entry; 232 BUG_ON(type >= FC_FC4_PROV_SIZE); 233 BUG_ON(!lport); 234 prov_entry = fc_passive_prov[type]; 235 if (type == FC_TYPE_FCP) { 236 if (prov_entry && prov_entry->recv) 237 lport->service_params |= FCP_SPPF_TARG_FCN; 238 } 239 } 240 241 void fc_lport_iterate(void (*notify)(struct fc_lport *, void *), void *arg) 242 { 243 struct fc_lport *lport; 244 245 mutex_lock(&fc_prov_mutex); 246 list_for_each_entry(lport, &fc_local_ports, lport_list) 247 notify(lport, arg); 248 mutex_unlock(&fc_prov_mutex); 249 } 250 EXPORT_SYMBOL(fc_lport_iterate); 251 252 /** 253 * fc_fc4_register_provider() - register FC-4 upper-level provider. 254 * @type: FC-4 type, such as FC_TYPE_FCP 255 * @prov: structure describing provider including ops vector. 256 * 257 * Returns 0 on success, negative error otherwise. 258 */ 259 int fc_fc4_register_provider(enum fc_fh_type type, struct fc4_prov *prov) 260 { 261 struct fc4_prov **prov_entry; 262 int ret = 0; 263 264 if (type >= FC_FC4_PROV_SIZE) 265 return -EINVAL; 266 mutex_lock(&fc_prov_mutex); 267 prov_entry = (prov->recv ? fc_passive_prov : fc_active_prov) + type; 268 if (*prov_entry) 269 ret = -EBUSY; 270 else 271 *prov_entry = prov; 272 mutex_unlock(&fc_prov_mutex); 273 return ret; 274 } 275 EXPORT_SYMBOL(fc_fc4_register_provider); 276 277 /** 278 * fc_fc4_deregister_provider() - deregister FC-4 upper-level provider. 279 * @type: FC-4 type, such as FC_TYPE_FCP 280 * @prov: structure describing provider including ops vector. 281 */ 282 void fc_fc4_deregister_provider(enum fc_fh_type type, struct fc4_prov *prov) 283 { 284 BUG_ON(type >= FC_FC4_PROV_SIZE); 285 mutex_lock(&fc_prov_mutex); 286 if (prov->recv) 287 RCU_INIT_POINTER(fc_passive_prov[type], NULL); 288 else 289 RCU_INIT_POINTER(fc_active_prov[type], NULL); 290 mutex_unlock(&fc_prov_mutex); 291 synchronize_rcu(); 292 } 293 EXPORT_SYMBOL(fc_fc4_deregister_provider); 294 295 /** 296 * fc_fc4_add_lport() - add new local port to list and run notifiers. 297 * @lport: The new local port. 298 */ 299 void fc_fc4_add_lport(struct fc_lport *lport) 300 { 301 mutex_lock(&fc_prov_mutex); 302 list_add_tail(&lport->lport_list, &fc_local_ports); 303 blocking_notifier_call_chain(&fc_lport_notifier_head, 304 FC_LPORT_EV_ADD, lport); 305 mutex_unlock(&fc_prov_mutex); 306 } 307 308 /** 309 * fc_fc4_del_lport() - remove local port from list and run notifiers. 310 * @lport: The new local port. 311 */ 312 void fc_fc4_del_lport(struct fc_lport *lport) 313 { 314 mutex_lock(&fc_prov_mutex); 315 list_del(&lport->lport_list); 316 blocking_notifier_call_chain(&fc_lport_notifier_head, 317 FC_LPORT_EV_DEL, lport); 318 mutex_unlock(&fc_prov_mutex); 319 } 320