realtek: l3: reorganize lock access

The layer 3 code shares the register access lock with the DSA driver.
It is currently unclear to which extent this is really needed. To
avoid permanent access to the DSA private structure reorganize the
locking as follows:

- create a lock pointer in the layer 3 control structure
- link it to the DSA lock during probing
- use the ctrl->lock pointer whenever needed.

Link: https://github.com/openwrt/openwrt/pull/23979
Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>

diff --git a/target/linux/realtek/files-6.18/drivers/net/dsa/rtl83xx/l3.c b/target/linux/realtek/files-6.18/drivers/net/dsa/rtl83xx/l3.c
index 9ea70949d960ca8a84e6cabd2428e484019d4f0f..b87e59fc3fd5fa52d098ce92032782e0436d49a3 100644 (file)
--- a/target/linux/realtek/files-6.18/drivers/net/dsa/rtl83xx/l3.c
+++ b/target/linux/realtek/files-6.18/drivers/net/dsa/rtl83xx/l3.c
@@ -694,11 +694,10 @@ static int otto_l3_port_dev_lower_find(struct net_device *dev, struct otto_l3_ct
  */
 static int otto_l3_alloc_router_mac(struct otto_l3_ctrl *ctrl, u64 mac)
 {
-       struct rtl838x_switch_priv *priv = ctrl->priv;
        struct otto_l3_router_mac m;
        int free_mac = -1;
 
-       mutex_lock(&priv->reg_mutex);
+       mutex_lock(ctrl->lock);
        for (int i = 0; i < MAX_ROUTER_MACS; i++) {
                ctrl->cfg->get_router_mac(ctrl, i, &m);
                if (free_mac < 0 && !m.valid) {
@@ -713,7 +712,7 @@ static int otto_l3_alloc_router_mac(struct otto_l3_ctrl *ctrl, u64 mac)
 
        if (free_mac < 0) {
                dev_err(ctrl->dev, "No free router MACs, cannot offload\n");
-               mutex_unlock(&priv->reg_mutex);
+               mutex_unlock(ctrl->lock);
                return -1;
        }
 
@@ -728,7 +727,7 @@ static int otto_l3_alloc_router_mac(struct otto_l3_ctrl *ctrl, u64 mac)
        m.action = L3_FORWARD;          /* Route the packet */
        ctrl->cfg->set_router_mac(ctrl, free_mac, &m);
 
-       mutex_unlock(&priv->reg_mutex);
+       mutex_unlock(ctrl->lock);
 
        return 0;
 }
@@ -832,12 +831,11 @@ static int otto_l3_930x_setup(struct otto_l3_ctrl *ctrl)
 
 static int otto_l3_alloc_egress_intf(struct otto_l3_ctrl *ctrl, u64 mac, int vlan)
 {
-       struct rtl838x_switch_priv *priv = ctrl->priv;
        struct otto_l3_intf intf;
        int free_mac = -1;
        u64 m;
 
-       mutex_lock(&priv->reg_mutex);
+       mutex_lock(ctrl->lock);
        for (int i = 0; i < MAX_SMACS; i++) {
                m = ctrl->cfg->get_egress_mac(ctrl, L3_EGRESS_DMACS + i);
                if (free_mac < 0 && !m) {
@@ -845,7 +843,7 @@ static int otto_l3_alloc_egress_intf(struct otto_l3_ctrl *ctrl, u64 mac, int vla
                        continue;
                }
                if (m == mac) {
-                       mutex_unlock(&priv->reg_mutex);
+                       mutex_unlock(ctrl->lock);
                        return i;
                }
        }
@@ -868,7 +866,7 @@ static int otto_l3_alloc_egress_intf(struct otto_l3_ctrl *ctrl, u64 mac, int vla
 
        ctrl->cfg->set_egress_mac(ctrl, L3_EGRESS_DMACS + free_mac, mac);
 
-       mutex_unlock(&priv->reg_mutex);
+       mutex_unlock(ctrl->lock);
 
        return free_mac;
 }
@@ -1013,18 +1011,17 @@ static void otto_l3_route_remove(struct otto_l3_ctrl *ctrl, struct otto_l3_route
 
 static struct otto_l3_route *otto_l3_host_route_alloc(struct otto_l3_ctrl *ctrl, u32 ip)
 {
-       struct rtl838x_switch_priv *priv = ctrl->priv;
        struct otto_l3_route *r;
        int idx = 0, err;
 
-       mutex_lock(&priv->reg_mutex);
+       mutex_lock(ctrl->lock);
 
        idx = find_first_zero_bit(ctrl->host_route_use_bm, MAX_HOST_ROUTES);
        dev_dbg(ctrl->dev, "id: %d, ip %pI4\n", idx, &ip);
 
        r = kzalloc(sizeof(*r), GFP_KERNEL);
        if (!r) {
-               mutex_unlock(&priv->reg_mutex);
+               mutex_unlock(ctrl->lock);
                return r;
        }
 
@@ -1040,13 +1037,13 @@ static struct otto_l3_route *otto_l3_host_route_alloc(struct otto_l3_ctrl *ctrl,
        err = rhltable_insert(&ctrl->routes, &r->linkage, otto_l3_route_ht_params);
        if (err) {
                dev_err(ctrl->dev, "Could not insert new rule\n");
-               mutex_unlock(&priv->reg_mutex);
+               mutex_unlock(ctrl->lock);
                goto out_free;
        }
 
        set_bit(idx, ctrl->host_route_use_bm);
 
-       mutex_unlock(&priv->reg_mutex);
+       mutex_unlock(ctrl->lock);
 
        return r;
 
@@ -1058,18 +1055,17 @@ out_free:
 
 static struct otto_l3_route *otto_l3_route_alloc(struct otto_l3_ctrl *ctrl, u32 ip)
 {
-       struct rtl838x_switch_priv *priv = ctrl->priv;
        struct otto_l3_route *r;
        int idx = 0, err;
 
-       mutex_lock(&priv->reg_mutex);
+       mutex_lock(ctrl->lock);
 
        idx = find_first_zero_bit(ctrl->route_use_bm, MAX_ROUTES);
        dev_dbg(ctrl->dev, "id: %d, ip %pI4\n", idx, &ip);
 
        r = kzalloc(sizeof(*r), GFP_KERNEL);
        if (!r) {
-               mutex_unlock(&priv->reg_mutex);
+               mutex_unlock(ctrl->lock);
                return r;
        }
 
@@ -1081,13 +1077,13 @@ static struct otto_l3_route *otto_l3_route_alloc(struct otto_l3_ctrl *ctrl, u32
        err = rhltable_insert(&ctrl->routes, &r->linkage, otto_l3_route_ht_params);
        if (err) {
                dev_err(ctrl->dev, "Could not insert new rule\n");
-               mutex_unlock(&priv->reg_mutex);
+               mutex_unlock(ctrl->lock);
                goto out_free;
        }
 
        set_bit(idx, ctrl->route_use_bm);
 
-       mutex_unlock(&priv->reg_mutex);
+       mutex_unlock(ctrl->lock);
 
        return r;
 
@@ -1478,6 +1474,8 @@ int otto_l3_probe(struct device *dev, struct rtl838x_switch_priv *priv)
        priv->l3_ctrl = ctrl;
        ctrl->priv = priv;
        ctrl->dev = priv->dev;
+       /* For now share the register access lock with the DSA driver */
+       ctrl->lock = &priv->reg_mutex;
 
        match = of_match_node(otto_l3_of_ids, dev->of_node);
        if (!match)

diff --git a/target/linux/realtek/files-6.18/drivers/net/dsa/rtl83xx/l3.h b/target/linux/realtek/files-6.18/drivers/net/dsa/rtl83xx/l3.h
index a318dbdaba5c41e26e89c2407ca8f9133dac0d35..494c850e808f5abce0f4fe32b05650b1d50c9b98 100644 (file)
--- a/target/linux/realtek/files-6.18/drivers/net/dsa/rtl83xx/l3.h
+++ b/target/linux/realtek/files-6.18/drivers/net/dsa/rtl83xx/l3.h
@@ -110,6 +110,7 @@ struct otto_l3_ctrl {
        unsigned long route_use_bm[MAX_ROUTES / 32];
        unsigned long host_route_use_bm[MAX_HOST_ROUTES / 32];
        struct otto_l3_intf *interfaces[MAX_INTERFACES];
+       struct mutex *lock; /* protect register access */
 };
 
 int otto_l3_probe(struct device *dev, struct rtl838x_switch_priv *priv);