1 files changed, 21 insertions, 17 deletions

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 0dc66e4fbb2c..28cfa642e39a 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -655,7 +655,7 @@ static struct tun_struct *tun_enable_queue(struct tun_file *tfile)
 	return tun;
 }
 
-static void tun_ptr_free(void *ptr)
+void tun_ptr_free(void *ptr)
 {
 	if (!ptr)
 		return;
@@ -667,6 +667,7 @@ static void tun_ptr_free(void *ptr)
 		__skb_array_destroy_skb(ptr);
 	}
 }
+EXPORT_SYMBOL_GPL(tun_ptr_free);
 
 static void tun_queue_purge(struct tun_file *tfile)
 {
@@ -1436,7 +1437,7 @@ static __poll_t tun_chr_poll(struct file *file, poll_table *wait)
 	__poll_t mask = 0;
 
 	if (!tun)
-		return POLLERR;
+		return EPOLLERR;
 
 	sk = tfile->socket.sk;
 
@@ -1445,16 +1446,16 @@ static __poll_t tun_chr_poll(struct file *file, poll_table *wait)
 	poll_wait(file, sk_sleep(sk), wait);
 
 	if (!ptr_ring_empty(&tfile->tx_ring))
-		mask |= POLLIN | POLLRDNORM;
+		mask |= EPOLLIN | EPOLLRDNORM;
 
 	if (tun->dev->flags & IFF_UP &&
 	    (sock_writeable(sk) ||
 	     (!test_and_set_bit(SOCKWQ_ASYNC_NOSPACE, &sk->sk_socket->flags) &&
 	      sock_writeable(sk))))
-		mask |= POLLOUT | POLLWRNORM;
+		mask |= EPOLLOUT | EPOLLWRNORM;
 
 	if (tun->dev->reg_state != NETREG_REGISTERED)
-		mask = POLLERR;
+		mask = EPOLLERR;
 
 	tun_put(tun);
 	return mask;
@@ -1488,27 +1489,23 @@ static struct sk_buff *tun_napi_alloc_frags(struct tun_file *tfile,
 	skb->truesize += skb->data_len;
 
 	for (i = 1; i < it->nr_segs; i++) {
+		struct page_frag *pfrag = &current->task_frag;
 		size_t fragsz = it->iov[i].iov_len;
-		unsigned long offset;
-		struct page *page;
-		void *data;
 
 		if (fragsz == 0 || fragsz > PAGE_SIZE) {
 			err = -EINVAL;
 			goto free;
 		}
 
-		local_bh_disable();
-		data = napi_alloc_frag(fragsz);
-		local_bh_enable();
-		if (!data) {
+		if (!skb_page_frag_refill(fragsz, pfrag, GFP_KERNEL)) {
 			err = -ENOMEM;
 			goto free;
 		}
 
-		page = virt_to_head_page(data);
-		offset = data - page_address(page);
-		skb_fill_page_desc(skb, i - 1, page, offset, fragsz);
+		skb_fill_page_desc(skb, i - 1, pfrag->page,
+				   pfrag->offset, fragsz);
+		page_ref_inc(pfrag->page);
+		pfrag->offset += fragsz;
 	}
 
 	return skb;
@@ -1646,6 +1643,7 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,
 	else
 		*skb_xdp = 0;
 
+	preempt_disable();
 	rcu_read_lock();
 	xdp_prog = rcu_dereference(tun->xdp_prog);
 	if (xdp_prog && !*skb_xdp) {
@@ -1666,9 +1664,11 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,
 			get_page(alloc_frag->page);
 			alloc_frag->offset += buflen;
 			err = xdp_do_redirect(tun->dev, &xdp, xdp_prog);
+			xdp_do_flush_map();
 			if (err)
 				goto err_redirect;
 			rcu_read_unlock();
+			preempt_enable();
 			return NULL;
 		case XDP_TX:
 			xdp_xmit = true;
@@ -1690,6 +1690,7 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,
 	skb = build_skb(buf, buflen);
 	if (!skb) {
 		rcu_read_unlock();
+		preempt_enable();
 		return ERR_PTR(-ENOMEM);
 	}
 
@@ -1702,10 +1703,12 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,
 		skb->dev = tun->dev;
 		generic_xdp_tx(skb, xdp_prog);
 		rcu_read_unlock();
+		preempt_enable();
 		return NULL;
 	}
 
 	rcu_read_unlock();
+	preempt_enable();
 
 	return skb;
 
@@ -1713,6 +1716,7 @@ err_redirect:
 	put_page(alloc_frag->page);
 err_xdp:
 	rcu_read_unlock();
+	preempt_enable();
 	this_cpu_inc(tun->pcpu_stats->rx_dropped);
 	return NULL;
 }
@@ -2303,8 +2307,8 @@ static void tun_sock_write_space(struct sock *sk)
 
 	wqueue = sk_sleep(sk);
 	if (wqueue && waitqueue_active(wqueue))
-		wake_up_interruptible_sync_poll(wqueue, POLLOUT |
-						POLLWRNORM | POLLWRBAND);
+		wake_up_interruptible_sync_poll(wqueue, EPOLLOUT |
+						EPOLLWRNORM | EPOLLWRBAND);
 
 	tfile = container_of(sk, struct tun_file, sk);
 	kill_fasync(&tfile->fasync, SIGIO, POLL_OUT);