/* * 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"); DEFINE_MUTEX(fc_prov_mutex); static LIST_HEAD(fc_local_ports); struct blocking_notifier_head fc_lport_notifier_head = BLOCKING_NOTIFIER_INIT(fc_lport_notifier_head); EXPORT_SYMBOL(fc_lport_notifier_head); /* * Providers which primarily send requests and PRLIs. */ struct fc4_prov *fc_active_prov[FC_FC4_PROV_SIZE] = { [0] = &fc_rport_t0_prov, [FC_TYPE_FCP] = &fc_rport_fcp_init, }; /* * Providers which receive requests. */ struct fc4_prov *fc_passive_prov[FC_FC4_PROV_SIZE] = { [FC_TYPE_ELS] = &fc_lport_els_prov, }; /** * 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); /** * fc_fc4_conf_lport_params() - Modify "service_params" of specified lport * if there is service provider (target provider) registered with libfc * for specified "fc_ft_type" * @lport: Local port which service_params needs to be modified * @type: FC-4 type, such as FC_TYPE_FCP */ void fc_fc4_conf_lport_params(struct fc_lport *lport, enum fc_fh_type type) { struct fc4_prov *prov_entry; BUG_ON(type >= FC_FC4_PROV_SIZE); BUG_ON(!lport); prov_entry = fc_passive_prov[type]; if (type == FC_TYPE_FCP) { if (prov_entry && prov_entry->recv) lport->service_params |= FCP_SPPF_TARG_FCN; } } void fc_lport_iterate(void (*notify)(struct fc_lport *, void *), void *arg) { struct fc_lport *lport; mutex_lock(&fc_prov_mutex); list_for_each_entry(lport, &fc_local_ports, lport_list) notify(lport, arg); mutex_unlock(&fc_prov_mutex); } EXPORT_SYMBOL(fc_lport_iterate); /** * fc_fc4_register_provider() - register FC-4 upper-level provider. * @type: FC-4 type, such as FC_TYPE_FCP * @prov: structure describing provider including ops vector. * * Returns 0 on success, negative error otherwise. */ int fc_fc4_register_provider(enum fc_fh_type type, struct fc4_prov *prov) { struct fc4_prov **prov_entry; int ret = 0; if (type >= FC_FC4_PROV_SIZE) return -EINVAL; mutex_lock(&fc_prov_mutex); prov_entry = (prov->recv ? fc_passive_prov : fc_active_prov) + type; if (*prov_entry) ret = -EBUSY; else *prov_entry = prov; mutex_unlock(&fc_prov_mutex); return ret; } EXPORT_SYMBOL(fc_fc4_register_provider); /** * fc_fc4_deregister_provider() - deregister FC-4 upper-level provider. * @type: FC-4 type, such as FC_TYPE_FCP * @prov: structure describing provider including ops vector. */ void fc_fc4_deregister_provider(enum fc_fh_type type, struct fc4_prov *prov) { BUG_ON(type >= FC_FC4_PROV_SIZE); mutex_lock(&fc_prov_mutex); if (prov->recv) rcu_assign_pointer(fc_passive_prov[type], NULL); else rcu_assign_pointer(fc_active_prov[type], NULL); mutex_unlock(&fc_prov_mutex); synchronize_rcu(); } EXPORT_SYMBOL(fc_fc4_deregister_provider); /** * fc_fc4_add_lport() - add new local port to list and run notifiers. * @lport: The new local port. */ void fc_fc4_add_lport(struct fc_lport *lport) { mutex_lock(&fc_prov_mutex); list_add_tail(&lport->lport_list, &fc_local_ports); blocking_notifier_call_chain(&fc_lport_notifier_head, FC_LPORT_EV_ADD, lport); mutex_unlock(&fc_prov_mutex); } /** * fc_fc4_del_lport() - remove local port from list and run notifiers. * @lport: The new local port. */ void fc_fc4_del_lport(struct fc_lport *lport) { mutex_lock(&fc_prov_mutex); list_del(&lport->lport_list); blocking_notifier_call_chain(&fc_lport_notifier_head, FC_LPORT_EV_DEL, lport); mutex_unlock(&fc_prov_mutex); }