[PATCH net-next v5 2/5] skbuff: add a parameter to __skb_frag_unref

From: Matteo Croce <mcroce@linux.microsoft.com>
To: netdev@vger.kernel.org, linux-mm@kvack.org
Cc: Ayush Sawal <ayush.sawal@chelsio.com>,
	Vinay Kumar Yadav <vinay.yadav@chelsio.com>,
	Rohit Maheshwari <rohitm@chelsio.com>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
	Marcin Wojtas <mw@semihalf.com>,
	Russell King <linux@armlinux.org.uk>,
	Mirko Lindner <mlindner@marvell.com>,
	Stephen Hemminger <stephen@networkplumber.org>,
	Tariq Toukan <tariqt@nvidia.com>,
	Jesper Dangaard Brouer <hawk@kernel.org>,
	Ilias Apalodimas <ilias.apalodimas@linaro.org>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	John Fastabend <john.fastabend@gmail.com>,
	Boris Pismenny <borisp@nvidia.com>, Arnd Bergmann <arnd@arndb.de>,
	Andrew Morton <akpm@linux-foundation.org>,
	"Peter Zijlstra (Intel)" <peterz@infradead.org>,
	Vlastimil Babka <vbabka@suse.cz>, Yu Zhao <yuzhao@google.com>,
	Will Deacon <will@kernel.org>, Fenghua Yu <fenghua.yu@intel.com>,
	Roman Gushchin <guro@fb.com>, Hugh Dickins <hughd@google.com>,
	Peter Xu <peterx@redhat.com>, Jason Gunthorpe <jgg@ziepe.ca>,
	Jonathan Lemon <jonathan.lemon@gmail.com>,
	Alexander Lobakin <alobakin@pm.me>,
	Cong Wang <cong.wang@bytedance.com>, wenxu <wenxu@ucloud.cn>,
	Kevin Hao <haokexin@gmail.com>,
	Jakub Sitnicki <jakub@cloudflare.com>,
	Marco Elver <elver@google.com>,
	Willem de Bruijn <willemb@google.com>,
	Miaohe Lin <linmiaohe@huawei.com>,
	Yunsheng Lin <linyunsheng@huawei.com>,
	Guillaume Nault <gnault@redhat.com>,
	linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org,
	bpf@vger.kernel.org, Matthew Wilcox <willy@infradead.org>,
	Eric Dumazet <edumazet@google.com>,
	David Ahern <dsahern@gmail.com>,
	Lorenzo Bianconi <lorenzo@kernel.org>,
	Saeed Mahameed <saeedm@nvidia.com>, Andrew Lunn <andrew@lunn.ch>,
	Paolo Abeni <pabeni@redhat.com>,
	Sven Auhagen <sven.auhagen@voleatech.de>
Subject: [PATCH net-next v5 2/5] skbuff: add a parameter to __skb_frag_unref
Date: Thu, 13 May 2021 18:58:43 +0200	[thread overview]
Message-ID: <20210513165846.23722-3-mcroce@linux.microsoft.com> (raw)
In-Reply-To: <20210513165846.23722-1-mcroce@linux.microsoft.com>

From: Matteo Croce <mcroce@microsoft.com>

This is a prerequisite patch, the next one is enabling recycling of
skbs and fragments. Add an extra argument on __skb_frag_unref() to
handle recycling, and update the current users of the function with that.

Signed-off-by: Matteo Croce <mcroce@microsoft.com>
---
 drivers/net/ethernet/marvell/sky2.c        | 2 +-
 drivers/net/ethernet/mellanox/mlx4/en_rx.c | 2 +-
 include/linux/skbuff.h                     | 8 +++++---
 net/core/skbuff.c                          | 4 ++--
 net/tls/tls_device.c                       | 2 +-
 5 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/marvell/sky2.c b/drivers/net/ethernet/marvell/sky2.c
index 222c32367b2c..aa0cde1dc5c0 100644
--- a/drivers/net/ethernet/marvell/sky2.c
+++ b/drivers/net/ethernet/marvell/sky2.c
@@ -2503,7 +2503,7 @@ static void skb_put_frags(struct sk_buff *skb, unsigned int hdr_space,
 
 		if (length == 0) {
 			/* don't need this page */
-			__skb_frag_unref(frag);
+			__skb_frag_unref(frag, false);
 			--skb_shinfo(skb)->nr_frags;
 		} else {
 			size = min(length, (unsigned) PAGE_SIZE);
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index e35e4d7ef4d1..cea62b8f554c 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -526,7 +526,7 @@ static int mlx4_en_complete_rx_desc(struct mlx4_en_priv *priv,
 fail:
 	while (nr > 0) {
 		nr--;
-		__skb_frag_unref(skb_shinfo(skb)->frags + nr);
+		__skb_frag_unref(skb_shinfo(skb)->frags + nr, false);
 	}
 	return 0;
 }
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index dbf820a50a39..7fcfea7e7b21 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -3081,10 +3081,12 @@ static inline void skb_frag_ref(struct sk_buff *skb, int f)
 /**
  * __skb_frag_unref - release a reference on a paged fragment.
  * @frag: the paged fragment
+ * @recycle: recycle the page if allocated via page_pool
  *
- * Releases a reference on the paged fragment @frag.
+ * Releases a reference on the paged fragment @frag
+ * or recycles the page via the page_pool API.
  */
-static inline void __skb_frag_unref(skb_frag_t *frag)
+static inline void __skb_frag_unref(skb_frag_t *frag, bool recycle)
 {
 	put_page(skb_frag_page(frag));
 }
@@ -3098,7 +3100,7 @@ static inline void __skb_frag_unref(skb_frag_t *frag)
  */
 static inline void skb_frag_unref(struct sk_buff *skb, int f)
 {
-	__skb_frag_unref(&skb_shinfo(skb)->frags[f]);
+	__skb_frag_unref(&skb_shinfo(skb)->frags[f], false);
 }
 
 /**
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 3ad22870298c..12b7e90dd2b5 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -664,7 +664,7 @@ static void skb_release_data(struct sk_buff *skb)
 	skb_zcopy_clear(skb, true);
 
 	for (i = 0; i < shinfo->nr_frags; i++)
-		__skb_frag_unref(&shinfo->frags[i]);
+		__skb_frag_unref(&shinfo->frags[i], false);
 
 	if (shinfo->frag_list)
 		kfree_skb_list(shinfo->frag_list);
@@ -3495,7 +3495,7 @@ int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen)
 		fragto = &skb_shinfo(tgt)->frags[merge];
 
 		skb_frag_size_add(fragto, skb_frag_size(fragfrom));
-		__skb_frag_unref(fragfrom);
+		__skb_frag_unref(fragfrom, false);
 	}
 
 	/* Reposition in the original skb */
diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index 76a6f8c2eec4..ad11db2c4f63 100644
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -127,7 +127,7 @@ static void destroy_record(struct tls_record_info *record)
 	int i;
 
 	for (i = 0; i < record->num_frags; i++)
-		__skb_frag_unref(&record->frags[i]);
+		__skb_frag_unref(&record->frags[i], false);
 	kfree(record);
 }
 
-- 
2.31.1

