caif: Move refcount from service layer to sock and dev.

Instead of having reference counts in caif service layers,
we hook into existing refcount handling in socket layer and netdevice.

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

3 files changed, 47 insertions, 21 deletions

diff --git a/include/net/caif/cfsrvl.h b/include/net/caif/cfsrvl.h
index 6c8279c1ae9a..0f5905241843 100644
--- a/include/net/caif/cfsrvl.h
+++ b/include/net/caif/cfsrvl.h
@@ -10,6 +10,7 @@
 #include <linux/stddef.h>
 #include <linux/types.h>
 #include <linux/kref.h>
+#include <linux/rculist.h>
 
 struct cfsrvl {
         struct cflayer layer;
@@ -17,9 +18,11 @@ struct cfsrvl {
         bool phy_flow_on;
         bool modem_flow_on;
         bool supports_flowctrl;
-        void (*release)(struct kref *);
+        void (*release)(struct cflayer *layer);
         struct dev_info dev_info;
-        struct kref ref;
+        void (*hold)(struct cflayer *lyr);
+        void (*put)(struct cflayer *lyr);
+        struct rcu_head rcu;
 };
 
 struct cflayer *cfvei_create(u8 linkid, struct dev_info *dev_info);
@@ -29,6 +32,10 @@ struct cflayer *cfvidl_create(u8 linkid, struct dev_info *dev_info);
 struct cflayer *cfrfml_create(u8 linkid, struct dev_info *dev_info,
                                 int mtu_size);
 struct cflayer *cfdbgl_create(u8 linkid, struct dev_info *dev_info);
+
+void cfsrvl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
+                     int phyid);
+
 bool cfsrvl_phyid_match(struct cflayer *layer, int phyid);
 
 void cfsrvl_init(struct cfsrvl *service,
@@ -40,23 +47,19 @@ u8 cfsrvl_getphyid(struct cflayer *layer);
 
 static inline void cfsrvl_get(struct cflayer *layr)
 {
-        struct cfsrvl *s;
-        if (layr == NULL)
+        struct cfsrvl *s = container_of(layr, struct cfsrvl, layer);
+        if (layr == NULL || layr->up == NULL || s->hold == NULL)
                 return;
-        s = container_of(layr, struct cfsrvl, layer);
-        kref_get(&s->ref);
+
+        s->hold(layr->up);
 }
 
 static inline void cfsrvl_put(struct cflayer *layr)
 {
-        struct cfsrvl *s;
-        if (layr == NULL)
+        struct cfsrvl *s = container_of(layr, struct cfsrvl, layer);
+        if (layr == NULL || layr->up == NULL || s->hold == NULL)
                 return;
-        s = container_of(layr, struct cfsrvl, layer);
 
-        WARN_ON(!s->release);
-        if (s->release)
-                kref_put(&s->ref, s->release);
+        s->put(layr->up);
 }
-
 #endif                          /* CFSRVL_H_ */
diff --git a/net/caif/cfrfml.c b/net/caif/cfrfml.c
index e2fb5fa75795..0deabb440051 100644
--- a/net/caif/cfrfml.c
+++ b/net/caif/cfrfml.c
@@ -31,9 +31,9 @@ struct cfrfml {
         spinlock_t sync;
 };
 
-static void cfrfml_release(struct kref *kref)
+static void cfrfml_release(struct cflayer *layer)
 {
-        struct cfsrvl *srvl = container_of(kref, struct cfsrvl, ref);
+        struct cfsrvl *srvl = container_of(layer, struct cfsrvl, layer);
         struct cfrfml *rfml = container_obj(&srvl->layer);
 
         if (rfml->incomplete_frm)
diff --git a/net/caif/cfsrvl.c b/net/caif/cfsrvl.c
index 24ba392f203b..535a1e72b366 100644
--- a/net/caif/cfsrvl.c
+++ b/net/caif/cfsrvl.c
@@ -10,6 +10,7 @@
 #include <linux/types.h>
 #include <linux/errno.h>
 #include <linux/slab.h>
+#include <linux/module.h>
 #include <net/caif/caif_layer.h>
 #include <net/caif/cfsrvl.h>
 #include <net/caif/cfpkt.h>
@@ -27,8 +28,8 @@ static void cfservl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
 {
         struct cfsrvl *service = container_obj(layr);
 
-        caif_assert(layr->up != NULL);
-        caif_assert(layr->up->ctrlcmd != NULL);
+        if (layr->up == NULL || layr->up->ctrlcmd == NULL)
+                return;
 
         switch (ctrl) {
         case CAIF_CTRLCMD_INIT_RSP:
@@ -151,9 +152,9 @@ static int cfservl_modemcmd(struct cflayer *layr, enum caif_modemcmd ctrl)
         return -EINVAL;
 }
 
-static void cfsrvl_release(struct kref *kref)
+static void cfsrvl_release(struct cflayer *layer)
 {
-        struct cfsrvl *service = container_of(kref, struct cfsrvl, ref);
+        struct cfsrvl *service = container_of(layer, struct cfsrvl, layer);
         kfree(service);
 }
 
@@ -173,10 +174,8 @@ void cfsrvl_init(struct cfsrvl *service,
         service->dev_info = *dev_info;
         service->supports_flowctrl = supports_flowctrl;
         service->release = cfsrvl_release;
-        kref_init(&service->ref);
 }
 
-
 bool cfsrvl_ready(struct cfsrvl *service, int *err)
 {
         if (service->open && service->modem_flow_on && service->phy_flow_on)
@@ -189,6 +188,7 @@ bool cfsrvl_ready(struct cfsrvl *service, int *err)
         *err = -EAGAIN;
         return false;
 }
+
 u8 cfsrvl_getphyid(struct cflayer *layer)
 {
         struct cfsrvl *servl = container_obj(layer);
@@ -200,3 +200,26 @@ bool cfsrvl_phyid_match(struct cflayer *layer, int phyid)
         struct cfsrvl *servl = container_obj(layer);
         return servl->dev_info.id == phyid;
 }
+
+void caif_free_client(struct cflayer *adap_layer)
+{
+        struct cfsrvl *servl;
+        if (adap_layer == NULL || adap_layer->dn == NULL)
+                return;
+        servl = container_obj(adap_layer->dn);
+        servl->release(&servl->layer);
+}
+EXPORT_SYMBOL(caif_free_client);
+
+void caif_client_register_refcnt(struct cflayer *adapt_layer,
+                                        void (*hold)(struct cflayer *lyr),
+                                        void (*put)(struct cflayer *lyr))
+{
+        struct cfsrvl *service;
+        service = container_of(adapt_layer->dn, struct cfsrvl, layer);
+
+        WARN_ON(adapt_layer == NULL || adapt_layer->dn == NULL);
+        service->hold = hold;
+        service->put = put;
+}
+EXPORT_SYMBOL(caif_client_register_refcnt);