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Diffstat (limited to 'kernel/drivers/scsi/libfc/fc_libfc.c')
-rw-r--r--kernel/drivers/scsi/libfc/fc_libfc.c331
1 files changed, 331 insertions, 0 deletions
diff --git a/kernel/drivers/scsi/libfc/fc_libfc.c b/kernel/drivers/scsi/libfc/fc_libfc.c
new file mode 100644
index 000000000..c11a638f3
--- /dev/null
+++ b/kernel/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);
+}