drivers/scsi/libfc/fc_elsct.c

   1 /*
   2  * Copyright(c) 2008 Intel Corporation. All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  16  *
  17  * Maintained at www.Open-FCoE.org
  18  */
  19
  20 /*
  21  * Provide interface to send ELS/CT FC frames
  22  */
  23
  24 #include <asm/unaligned.h>
  25 #include <scsi/fc/fc_gs.h>
  26 #include <scsi/fc/fc_ns.h>
  27 #include <scsi/fc/fc_els.h>
  28 #include <scsi/libfc.h>
  29 #include <scsi/fc_encode.h>
  30
  31 /*
  32  * fc_elsct_send - sends ELS/CT frame
  33  */
  34 static struct fc_seq *fc_elsct_send(struct fc_lport *lport,
  35                                     u32 did,
  36                                     struct fc_frame *fp,
  37                                     unsigned int op,
  38                                     void (*resp)(struct fc_seq *,
  39                                                  struct fc_frame *fp,
  40                                                  void *arg),
  41                                     void *arg, u32 timer_msec)
  42 {
  43         enum fc_rctl r_ctl;
  44         enum fc_fh_type fh_type;
  45         int rc;
  46
  47         /* ELS requests */
  48         if ((op >= ELS_LS_RJT) && (op <= ELS_AUTH_ELS))
  49                 rc = fc_els_fill(lport, did, fp, op, &r_ctl, &fh_type);
  50         else {
  51                 /* CT requests */
  52                 rc = fc_ct_fill(lport, did, fp, op, &r_ctl, &fh_type);
  53                 did = FC_FID_DIR_SERV;
  54         }
  55
  56         if (rc) {
  57                 fc_frame_free(fp);
  58                 return NULL;
  59         }
  60
  61         fc_fill_fc_hdr(fp, r_ctl, did, fc_host_port_id(lport->host), fh_type,
  62                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
  63
  64         return lport->tt.exch_seq_send(lport, fp, resp, NULL, arg, timer_msec);
  65 }
  66
  67 int fc_elsct_init(struct fc_lport *lport)
  68 {
  69         if (!lport->tt.elsct_send)
  70                 lport->tt.elsct_send = fc_elsct_send;
  71
  72         return 0;
  73 }
  74 EXPORT_SYMBOL(fc_elsct_init);
  75
  76 /**
  77  * fc_els_resp_type() - return string describing ELS response for debug.
  78  * @fp: frame pointer with possible error code.
  79  */
  80 const char *fc_els_resp_type(struct fc_frame *fp)
  81 {
  82         const char *msg;
  83         if (IS_ERR(fp)) {
  84                 switch (-PTR_ERR(fp)) {
  85                 case FC_NO_ERR:
  86                         msg = "response no error";
  87                         break;
  88                 case FC_EX_TIMEOUT:
  89                         msg = "response timeout";
  90                         break;
  91                 case FC_EX_CLOSED:
  92                         msg = "response closed";
  93                         break;
  94                 default:
  95                         msg = "response unknown error";
  96                         break;
  97                 }
  98         } else {
  99                 switch (fc_frame_payload_op(fp)) {
 100                 case ELS_LS_ACC:
 101                         msg = "accept";
 102                         break;
 103                 case ELS_LS_RJT:
 104                         msg = "reject";
 105                         break;
 106                 default:
 107                         msg = "response unknown ELS";
 108                         break;
 109                 }
 110         }
 111         return msg;
 112 }