diff options
Diffstat (limited to 'drivers/scsi/libfc/fc_libfc.c')
| -rw-r--r-- | drivers/scsi/libfc/fc_libfc.c | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/drivers/scsi/libfc/fc_libfc.c b/drivers/scsi/libfc/fc_libfc.c new file mode 100644 index 000000000..c11a638f3 --- /dev/null +++ b/drivers/scsi/libfc/fc_libfc.c @@ -0,0 +1,331 @@ +/* + * 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 <linux/module.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. + * @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, + 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)); + if (crc) + *crc = crc32(*crc, buf, sg_bytes); + memcpy((char *)page_addr + (off & ~PAGE_MASK), buf, sg_bytes); + kunmap_atomic(page_addr); + 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_INIT_POINTER(fc_passive_prov[type], NULL); + else + RCU_INIT_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); +} |