tun: use netdev_alloc_frag() in tun_napi_alloc_frags()

In order to cook skbs in the same way than Ethernet drivers,
it is probably better to not use GFP_KERNEL, but rather
use the GFP_ATOMIC and PFMEMALLOC mechanisms provided by
netdev_alloc_frag().

This would allow to use tun driver even in memory stress
situations, especially if swap is used over this tun channel.

Fixes: 90e33d4594 ("tun: enable napi_gro_frags() for TUN/TAP driver")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Petar Penkov <peterpenkov96@gmail.com>
Cc: Mahesh Bandewar <maheshb@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2018-11-18 07:37:33 -08:00 committed by David S. Miller
parent 05b0e1d698
commit aa6daacaa1

View File

@ -1478,23 +1478,22 @@ 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;
struct page *page;
void *frag;
if (fragsz == 0 || fragsz > PAGE_SIZE) {
err = -EINVAL;
goto free;
}
if (!skb_page_frag_refill(fragsz, pfrag, GFP_KERNEL)) {
frag = netdev_alloc_frag(fragsz);
if (!frag) {
err = -ENOMEM;
goto free;
}
skb_fill_page_desc(skb, i - 1, pfrag->page,
pfrag->offset, fragsz);
page_ref_inc(pfrag->page);
pfrag->offset += fragsz;
page = virt_to_head_page(frag);
skb_fill_page_desc(skb, i - 1, page,
frag - page_address(page), fragsz);
}
return skb;