net: marvell: prestera: Refactor get/put VR functions

* Use refcount, instead of uint
* Increment/decrement recount inside get/put
* Fix error path in __prestera_vr_create. Remove unnecessary kfree.
* Make __prestera_vr_destroy symmetric to "create"

Fixes: bca5859bc6c6 ("net: marvell: prestera: add hardware router objects accounting")
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Link: https://lore.kernel.org/r/20220111011014.4418-1-yevhen.orlov@plvision.eu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/marvell/prestera/prestera_router_hw.c b/drivers/net/ethernet/marvell/prestera/prestera_router_hw.c
index 5866a4b..d5befd1 100644 (file)
--- a/drivers/net/ethernet/marvell/prestera/prestera_router_hw.c
+++ b/drivers/net/ethernet/marvell/prestera/prestera_router_hw.c
@@ -47,13 +47,8 @@ static struct prestera_vr *__prestera_vr_create(struct prestera_switch *sw,
                                                struct netlink_ext_ack *extack)
 {
        struct prestera_vr *vr;
-       u16 hw_vr_id;
        int err;
 
-       err = prestera_hw_vr_create(sw, &hw_vr_id);
-       if (err)
-               return ERR_PTR(-ENOMEM);
-
        vr = kzalloc(sizeof(*vr), GFP_KERNEL);
        if (!vr) {
                err = -ENOMEM;
@@ -61,23 +56,26 @@ static struct prestera_vr *__prestera_vr_create(struct prestera_switch *sw,
        }
 
        vr->tb_id = tb_id;
-       vr->hw_vr_id = hw_vr_id;
+
+       err = prestera_hw_vr_create(sw, &vr->hw_vr_id);
+       if (err)
+               goto err_hw_create;
 
        list_add(&vr->router_node, &sw->router->vr_list);
 
        return vr;
 
-err_alloc_vr:
-       prestera_hw_vr_delete(sw, hw_vr_id);
+err_hw_create:
        kfree(vr);
+err_alloc_vr:
        return ERR_PTR(err);
 }
 
 static void __prestera_vr_destroy(struct prestera_switch *sw,
                                  struct prestera_vr *vr)
 {
-       prestera_hw_vr_delete(sw, vr->hw_vr_id);
        list_del(&vr->router_node);
+       prestera_hw_vr_delete(sw, vr->hw_vr_id);
        kfree(vr);
 }
 
@@ -87,17 +85,22 @@ static struct prestera_vr *prestera_vr_get(struct prestera_switch *sw, u32 tb_id
        struct prestera_vr *vr;
 
        vr = __prestera_vr_find(sw, tb_id);
-       if (!vr)
+       if (vr) {
+               refcount_inc(&vr->refcount);
+       } else {
                vr = __prestera_vr_create(sw, tb_id, extack);
-       if (IS_ERR(vr))
-               return ERR_CAST(vr);
+               if (IS_ERR(vr))
+                       return ERR_CAST(vr);
+
+               refcount_set(&vr->refcount, 1);
+       }
 
        return vr;
 }
 
 static void prestera_vr_put(struct prestera_switch *sw, struct prestera_vr *vr)
 {
-       if (!vr->ref_cnt)
+       if (refcount_dec_and_test(&vr->refcount))
                __prestera_vr_destroy(sw, vr);
 }
 
@@ -158,7 +161,6 @@ void prestera_rif_entry_destroy(struct prestera_switch *sw,
        iface.vr_id = e->vr->hw_vr_id;
        prestera_hw_rif_delete(sw, e->hw_id, &iface);
 
-       e->vr->ref_cnt--;
        prestera_vr_put(sw, e->vr);
        kfree(e);
 }
@@ -183,7 +185,6 @@ prestera_rif_entry_create(struct prestera_switch *sw,
        if (IS_ERR(e->vr))
                goto err_vr_get;
 
-       e->vr->ref_cnt++;
        memcpy(&e->addr, addr, sizeof(e->addr));
 
        /* HW */
@@ -198,7 +199,6 @@ prestera_rif_entry_create(struct prestera_switch *sw,
        return e;
 
 err_hw_create:
-       e->vr->ref_cnt--;
        prestera_vr_put(sw, e->vr);
 err_vr_get:
 err_key_copy:

diff --git a/drivers/net/ethernet/marvell/prestera/prestera_router_hw.h b/drivers/net/ethernet/marvell/prestera/prestera_router_hw.h
index fed5359..ab5e013 100644 (file)
--- a/drivers/net/ethernet/marvell/prestera/prestera_router_hw.h
+++ b/drivers/net/ethernet/marvell/prestera/prestera_router_hw.h
@@ -6,7 +6,7 @@
 
 struct prestera_vr {
        struct list_head router_node;
-       unsigned int ref_cnt;
+       refcount_t refcount;
        u32 tb_id;                      /* key (kernel fib table id) */
        u16 hw_vr_id;                   /* virtual router ID */
        u8 __pad[2];