libfcoe: Fix Conflicting FCFs issue in the fabric
authorKrishna Mohan <krmohan@cisco.com>
Fri, 1 Mar 2013 11:35:31 +0000 (11:35 +0000)
committerRobert Love <robert.w.love@intel.com>
Fri, 10 May 2013 17:19:19 +0000 (10:19 -0700)
When multiple FCFs in use, and first FIP Advertisement received is
with "Available for Login" i.e A bit set to 0, FCF selection will fail.
The fix is to remove the assumption in the code that first FCF is only
allowed selectable FCF.
Consider the scenario fip->fcfs contains FCF1(fabricname X, marked A=0)
FCF2(fabricname Y, marked A=1). list_first_entry(first) points to FCF1
and 1st iteration we ignore the FCF and on 2nd iteration we compare
FCF1 & FCF2 fabric name and we fails to perform FCF selection.

Signed-off-by: Krishna Mohan <krmohan@cisco.com>
Reviewed-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
drivers/scsi/fcoe/fcoe_ctlr.c

index a76247201be570987fe28b44545184bd777e65c0..4c7764181b7936c8ba41c561a5eb41d721c119d4 100644 (file)
@@ -1548,9 +1548,6 @@ static struct fcoe_fcf *fcoe_ctlr_select(struct fcoe_ctlr *fip)
 {
        struct fcoe_fcf *fcf;
        struct fcoe_fcf *best = fip->sel_fcf;
-       struct fcoe_fcf *first;
-
-       first = list_first_entry(&fip->fcfs, struct fcoe_fcf, list);
 
        list_for_each_entry(fcf, &fip->fcfs, list) {
                LIBFCOE_FIP_DBG(fip, "consider FCF fab %16.16llx "
@@ -1568,17 +1565,15 @@ static struct fcoe_fcf *fcoe_ctlr_select(struct fcoe_ctlr *fip)
                                        "" : "un");
                        continue;
                }
-               if (fcf->fabric_name != first->fabric_name ||
-                   fcf->vfid != first->vfid ||
-                   fcf->fc_map != first->fc_map) {
+               if (!best || fcf->pri < best->pri || best->flogi_sent)
+                       best = fcf;
+               if (fcf->fabric_name != best->fabric_name ||
+                   fcf->vfid != best->vfid ||
+                   fcf->fc_map != best->fc_map) {
                        LIBFCOE_FIP_DBG(fip, "Conflicting fabric, VFID, "
                                        "or FC-MAP\n");
                        return NULL;
                }
-               if (fcf->flogi_sent)
-                       continue;
-               if (!best || fcf->pri < best->pri || best->flogi_sent)
-                       best = fcf;
        }
        fip->sel_fcf = best;
        if (best) {