1 files changed, 47 insertions, 2 deletions

diff --git a/net/core/sock.c b/net/core/sock.c
index 2693f7649222..727114cd6f7e 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1744,6 +1744,45 @@ struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
 }
 EXPORT_SYMBOL(sock_alloc_send_skb);
 
+/* On 32bit arches, an skb frag is limited to 2^15 */
+#define SKB_FRAG_PAGE_ORDER     get_order(32768)
+
+bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
+{
+        int order;
+
+        if (pfrag->page) {
+                if (atomic_read(&pfrag->page->_count) == 1) {
+                        pfrag->offset = 0;
+                        return true;
+                }
+                if (pfrag->offset < pfrag->size)
+                        return true;
+                put_page(pfrag->page);
+        }
+
+        /* We restrict high order allocations to users that can afford to wait */
+        order = (sk->sk_allocation & __GFP_WAIT) ? SKB_FRAG_PAGE_ORDER : 0;
+
+        do {
+                gfp_t gfp = sk->sk_allocation;
+
+                if (order)
+                        gfp |= __GFP_COMP | __GFP_NOWARN;
+                pfrag->page = alloc_pages(gfp, order);
+                if (likely(pfrag->page)) {
+                        pfrag->offset = 0;
+                        pfrag->size = PAGE_SIZE << order;
+                        return true;
+                }
+        } while (--order >= 0);
+
+        sk_enter_memory_pressure(sk);
+        sk_stream_moderate_sndbuf(sk);
+        return false;
+}
+EXPORT_SYMBOL(sk_page_frag_refill);
+
 static void __lock_sock(struct sock *sk)
         __releases(&sk->sk_lock.slock)
         __acquires(&sk->sk_lock.slock)
@@ -2173,8 +2212,8 @@ void sock_init_data(struct socket *sock, struct sock *sk)
         sk->sk_error_report     =       sock_def_error_report;
         sk->sk_destruct         =       sock_def_destruct;
 
-        sk->sk_sndmsg_page      =       NULL;
-        sk->sk_sndmsg_off       =       0;
+        sk->sk_frag.page        =       NULL;
+        sk->sk_frag.offset      =       0;
         sk->sk_peek_off         =       -1;
 
         sk->sk_peer_pid         =       NULL;
@@ -2417,6 +2456,12 @@ void sk_common_release(struct sock *sk)
         xfrm_sk_free_policy(sk);
 
         sk_refcnt_debug_release(sk);
+
+        if (sk->sk_frag.page) {
+                put_page(sk->sk_frag.page);
+                sk->sk_frag.page = NULL;
+        }
+
         sock_put(sk);
 }
 EXPORT_SYMBOL(sk_common_release);