[SCSI] libfc: add interface to allocate a sequence for incoming requests

For incoming ELS and FCP requests, we often don't require an
exchange and sequence, however, sometimes we do.  For those cases,
(primarily FCP requests for targets) add a function to set up
the exchange and sequence.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

diff --git a/drivers/scsi/libfc/fc_exch.c b/drivers/scsi/libfc/fc_exch.c
index 61eabd3ce4365ee326e52b166f20864e47954c23..027042a6de3bb1173b2919dac3c48f0b63eda6a0 100644 (file)
--- a/drivers/scsi/libfc/fc_exch.c
+++ b/drivers/scsi/libfc/fc_exch.c
@@ -1230,6 +1230,28 @@ free:
        fc_frame_free(rx_fp);
 }
 
+/**
+ * fc_seq_assign() - Assign exchange and sequence for incoming request
+ * @lport: The local port that received the request
+ * @fp:    The request frame
+ *
+ * On success, the sequence pointer will be returned and also in fr_seq(@fp).
+ */
+static struct fc_seq *fc_seq_assign(struct fc_lport *lport, struct fc_frame *fp)
+{
+       struct fc_exch_mgr_anchor *ema;
+
+       WARN_ON(lport != fr_dev(fp));
+       WARN_ON(fr_seq(fp));
+       fr_seq(fp) = NULL;
+
+       list_for_each_entry(ema, &lport->ema_list, ema_list)
+               if ((!ema->match || ema->match(fp)) &&
+                   fc_seq_lookup_recip(lport, ema->mp, fp) != FC_RJT_NONE)
+                       break;
+       return fr_seq(fp);
+}
+
 /**
  * fc_exch_recv_req() - Handler for an incoming request where is other
  *                     end is originating the sequence
@@ -2283,6 +2305,9 @@ int fc_exch_init(struct fc_lport *lport)
        if (!lport->tt.seq_exch_abort)
                lport->tt.seq_exch_abort = fc_seq_exch_abort;
 
+       if (!lport->tt.seq_assign)
+               lport->tt.seq_assign = fc_seq_assign;
+
        return 0;
 }
 EXPORT_SYMBOL(fc_exch_init);

diff --git a/include/scsi/libfc.h b/include/scsi/libfc.h
index a6414ec63809acc5a8b855c95461d10bd3317db1..605f1d7861a7715d4be1755437e4bd587e1581e8 100644 (file)
--- a/include/scsi/libfc.h
+++ b/include/scsi/libfc.h
@@ -555,6 +555,13 @@ struct libfc_function_template {
         */
        struct fc_seq *(*seq_start_next)(struct fc_seq *);
 
+       /*
+        * Assign a sequence for an incoming request frame.
+        *
+        * STATUS: OPTIONAL
+        */
+       struct fc_seq *(*seq_assign)(struct fc_lport *, struct fc_frame *);
+
        /*
         * Reset an exchange manager, completing all sequences and exchanges.
         * If s_id is non-zero, reset only exchanges originating from that FID.