[PATCH bpf-next 02/11] xdp: export xdp_rxq_info_unreg_mem_model

["Björn Töpel" <bjorn.topel@gmail.com>]

From: Björn Töpel <bjorn.topel@intel.com>

Export __xdp_rxq_info_unreg_mem_model as xdp_rxq_info_unreg_mem_model,
so it can be used from netdev drivers. Also, add additional checks for
the memory type.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
---
 include/net/xdp.h |  1 +
 net/core/xdp.c    | 15 +++++++++++++--
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/include/net/xdp.h b/include/net/xdp.h
index 0d5c6fb4b2e2..0f25b3675c5c 100644
--- a/include/net/xdp.h
+++ b/include/net/xdp.h
@@ -136,6 +136,7 @@ void xdp_rxq_info_unused(struct xdp_rxq_info *xdp_rxq);
 bool xdp_rxq_info_is_reg(struct xdp_rxq_info *xdp_rxq);
 int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq,
 			       enum xdp_mem_type type, void *allocator);
+void xdp_rxq_info_unreg_mem_model(struct xdp_rxq_info *xdp_rxq);
 
 /* Drivers not supporting XDP metadata can use this helper, which
  * rejects any room expansion for metadata as a result.
diff --git a/net/core/xdp.c b/net/core/xdp.c
index be6cb2f0e722..654dbb19707e 100644
--- a/net/core/xdp.c
+++ b/net/core/xdp.c
@@ -94,11 +94,21 @@ static void __xdp_mem_allocator_rcu_free(struct rcu_head *rcu)
 	kfree(xa);
 }
 
-static void __xdp_rxq_info_unreg_mem_model(struct xdp_rxq_info *xdp_rxq)
+void xdp_rxq_info_unreg_mem_model(struct xdp_rxq_info *xdp_rxq)
 {
 	struct xdp_mem_allocator *xa;
 	int id = xdp_rxq->mem.id;
 
+	if (xdp_rxq->reg_state != REG_STATE_REGISTERED) {
+		WARN(1, "Missing register, driver bug");
+		return;
+	}
+
+	if (xdp_rxq->mem.type != MEM_TYPE_PAGE_POOL &&
+	    xdp_rxq->mem.type != MEM_TYPE_ZERO_COPY) {
+		return;
+	}
+
 	if (id == 0)
 		return;
 
@@ -110,6 +120,7 @@ static void __xdp_rxq_info_unreg_mem_model(struct xdp_rxq_info *xdp_rxq)
 
 	mutex_unlock(&mem_id_lock);
 }
+EXPORT_SYMBOL_GPL(xdp_rxq_info_unreg_mem_model);
 
 void xdp_rxq_info_unreg(struct xdp_rxq_info *xdp_rxq)
 {
@@ -119,7 +130,7 @@ void xdp_rxq_info_unreg(struct xdp_rxq_info *xdp_rxq)
 
 	WARN(!(xdp_rxq->reg_state == REG_STATE_REGISTERED), "Driver BUG");
 
-	__xdp_rxq_info_unreg_mem_model(xdp_rxq);
+	xdp_rxq_info_unreg_mem_model(xdp_rxq);
 
 	xdp_rxq->reg_state = REG_STATE_UNREGISTERED;
 	xdp_rxq->dev = NULL;
-- 
2.17.1