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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright(c) 2009 Intel Corporation. All rights reserved.4 *5 * Maintained at www.Open-FCoE.org6 */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 16#include "fc_encode.h"17#include "fc_libfc.h"18 19MODULE_AUTHOR("Open-FCoE.org");20MODULE_DESCRIPTION("libfc");21MODULE_LICENSE("GPL v2");22 23unsigned int fc_debug_logging;24module_param_named(debug_logging, fc_debug_logging, int, S_IRUGO|S_IWUSR);25MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels");26 27DEFINE_MUTEX(fc_prov_mutex);28static LIST_HEAD(fc_local_ports);29struct blocking_notifier_head fc_lport_notifier_head =30 BLOCKING_NOTIFIER_INIT(fc_lport_notifier_head);31EXPORT_SYMBOL(fc_lport_notifier_head);32 33/*34 * Providers which primarily send requests and PRLIs.35 */36struct 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 */44struct 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.ko50 */51static 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;68destroy_em:69 fc_destroy_exch_mgr();70destroy_pkt_cache:71 fc_destroy_fcp();72 return rc;73}74module_init(libfc_init);75 76/**77 * libfc_exit() - Tear down libfc.ko78 */79static void __exit libfc_exit(void)80{81 fc_destroy_fcp();82 fc_destroy_exch_mgr();83 fc_destroy_rport();84}85module_exit(libfc_exit);86 87/**88 * fc_copy_buffer_to_sglist() - This routine copies the data of a buffer89 * 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 */99u32 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 resources114 * 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 request147 * @fp: reply frame containing header to be filled in148 * @in_fp: request frame containing header to use in filling in reply149 * @r_ctl: R_CTL value for header150 * @f_ctl: F_CTL value for header, with 0 pad151 * @seq_cnt: sequence count for the header, ignored if frame has a sequence152 * @parm_offset: parameter / offset value153 */154void 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}201EXPORT_SYMBOL(fc_fill_hdr);202 203/**204 * fc_fill_reply_hdr() - fill FC reply header fields based on request205 * @fp: reply frame containing header to be filled in206 * @in_fp: request frame containing header to use in filling in reply207 * @r_ctl: R_CTL value for reply208 * @parm_offset: parameter / offset value209 */210void 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}220EXPORT_SYMBOL(fc_fill_reply_hdr);221 222/**223 * fc_fc4_conf_lport_params() - Modify "service_params" of specified lport224 * if there is service provider (target provider) registered with libfc225 * for specified "fc_ft_type"226 * @lport: Local port which service_params needs to be modified227 * @type: FC-4 type, such as FC_TYPE_FCP228 */229void 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 241void 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}250EXPORT_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_FCP255 * @prov: structure describing provider including ops vector.256 *257 * Returns 0 on success, negative error otherwise.258 */259int 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 else271 *prov_entry = prov;272 mutex_unlock(&fc_prov_mutex);273 return ret;274}275EXPORT_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_FCP280 * @prov: structure describing provider including ops vector.281 */282void 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 else289 RCU_INIT_POINTER(fc_active_prov[type], NULL);290 mutex_unlock(&fc_prov_mutex);291 synchronize_rcu();292}293EXPORT_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 */299void 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 */312void 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