caif: Use link layer MTU instead of fixed MTU

Previously CAIF supported maximum transfer size of ~4050.
The transfer size is now calculated dynamically based on the
link layers mtu size.

Signed-off-by: Sjur Braendeland@stericsson.com
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 40 insertions, 4 deletions

diff --git a/net/caif/cfcnfg.c b/net/caif/cfcnfg.c
index cff2dcb9efe4..1c29189b344d 100644
--- a/net/caif/cfcnfg.c
+++ b/net/caif/cfcnfg.c
@@ -6,6 +6,7 @@
 #include <linux/kernel.h>
 #include <linux/stddef.h>
 #include <linux/slab.h>
+#include <linux/netdevice.h>
 #include <net/caif/caif_layer.h>
 #include <net/caif/cfpkt.h>
 #include <net/caif/cfcnfg.h>
@@ -42,6 +43,15 @@ struct cfcnfg_phyinfo {
 
         /* Information about the physical device */
         struct dev_info dev_info;
+
+        /* Interface index */
+        int ifindex;
+
+        /* Use Start of frame extension */
+        bool use_stx;
+
+        /* Use Start of frame checksum */
+        bool use_fcs;
 };
 
 struct cfcnfg {
@@ -249,9 +259,20 @@ static void cfcnfg_linkdestroy_rsp(struct cflayer *layer, u8 channel_id)
 {
 }
 
+int protohead[CFCTRL_SRV_MASK] = {
+        [CFCTRL_SRV_VEI] = 4,
+        [CFCTRL_SRV_DATAGRAM] = 7,
+        [CFCTRL_SRV_UTIL] = 4,
+        [CFCTRL_SRV_RFM] = 3,
+        [CFCTRL_SRV_DBG] = 3,
+};
+
 int cfcnfg_add_adaptation_layer(struct cfcnfg *cnfg,
                                 struct cfctrl_link_param *param,
-                                struct cflayer *adap_layer)
+                                struct cflayer *adap_layer,
+                                int *ifindex,
+                                int *proto_head,
+                                int *proto_tail)
 {
         struct cflayer *frml;
         if (adap_layer == NULL) {
@@ -277,6 +298,14 @@ int cfcnfg_add_adaptation_layer(struct cfcnfg *cnfg,
                      param->phyid);
         caif_assert(cnfg->phy_layers[param->phyid].phy_layer->id ==
                      param->phyid);
+
+        *ifindex = cnfg->phy_layers[param->phyid].ifindex;
+        *proto_head =
+                protohead[param->linktype]+
+                (cnfg->phy_layers[param->phyid].use_stx ? 1 : 0);
+
+        *proto_tail = 2;
+
         /* FIXME: ENUMERATE INITIALLY WHEN ACTIVATING PHYSICAL INTERFACE */
         cfctrl_enum_req(cnfg->ctrl, param->phyid);
         return cfctrl_linkup_request(cnfg->ctrl, param, adap_layer);
@@ -298,6 +327,8 @@ cfcnfg_linkup_rsp(struct cflayer *layer, u8 channel_id, enum cfctrl_srv serv,
         struct cfcnfg *cnfg = container_obj(layer);
         struct cflayer *servicel = NULL;
         struct cfcnfg_phyinfo *phyinfo;
+        struct net_device *netdev;
+
         if (adapt_layer == NULL) {
                 pr_debug("CAIF: %s(): link setup response "
                                 "but no client exist, send linkdown back\n",
@@ -329,8 +360,9 @@ cfcnfg_linkup_rsp(struct cflayer *layer, u8 channel_id, enum cfctrl_srv serv,
                 servicel = cfdgml_create(channel_id, &phyinfo->dev_info);
                 break;
         case CFCTRL_SRV_RFM:
+                netdev = phyinfo->dev_info.dev;
                 servicel = cfrfml_create(channel_id, &phyinfo->dev_info,
-                                                RFM_FRAGMENT_SIZE);
+                                                netdev->mtu);
                 break;
         case CFCTRL_SRV_UTIL:
                 servicel = cfutill_create(channel_id, &phyinfo->dev_info);
@@ -361,8 +393,8 @@ cfcnfg_linkup_rsp(struct cflayer *layer, u8 channel_id, enum cfctrl_srv serv,
 
 void
 cfcnfg_add_phy_layer(struct cfcnfg *cnfg, enum cfcnfg_phy_type phy_type,
-                     void *dev, struct cflayer *phy_layer, u16 *phyid,
-                     enum cfcnfg_phy_preference pref,
+                     struct net_device *dev, struct cflayer *phy_layer,
+                     u16 *phyid, enum cfcnfg_phy_preference pref,
                      bool fcs, bool stx)
 {
         struct cflayer *frml;
@@ -416,6 +448,10 @@ cfcnfg_add_phy_layer(struct cfcnfg *cnfg, enum cfcnfg_phy_type phy_type,
         cnfg->phy_layers[*phyid].dev_info.dev = dev;
         cnfg->phy_layers[*phyid].phy_layer = phy_layer;
         cnfg->phy_layers[*phyid].phy_ref_count = 0;
+        cnfg->phy_layers[*phyid].ifindex = dev->ifindex;
+        cnfg->phy_layers[*phyid].use_stx = stx;
+        cnfg->phy_layers[*phyid].use_fcs = fcs;
+
         phy_layer->type = phy_type;
         frml = cffrml_create(*phyid, fcs);
         if (!frml) {