[SCSI] libfc: add interface to allocate a sequence for incoming requests
Joe Eykholt [Tue, 20 Jul 2010 22:21:07 +0000 (15:21 -0700)]
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>

drivers/scsi/libfc/fc_exch.c
include/scsi/libfc.h

index 61eabd3..027042a 100644 (file)
@@ -1231,6 +1231,28 @@ free:
 }
 
 /**
+ * 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
  * @lport: The local port that received the request
@@ -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);
index a6414ec..605f1d7 100644 (file)
@@ -556,6 +556,13 @@ 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.
         * If d_id is non-zero, reset only exchanges sending to that FID.