[PATCH v5 02/13] datagram: open-code copy_page_to_iter

From: Sagi Grimberg
Date: Mon Dec 03 2018 - 20:53:58 EST


From: Sagi Grimberg <sagi@xxxxxxxxxxxxxxxxx>

This will be useful to consolidate skb_copy_and_hash_datagram_iter and
skb_copy_and_csum_datagram to a single code path.

Acked-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sagi Grimberg <sagi@xxxxxxxxxxxxxxxxx>
---
net/core/datagram.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/net/core/datagram.c b/net/core/datagram.c
index 57f3a6fcfc1e..abe642181b64 100644
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -445,11 +445,14 @@ int skb_copy_datagram_iter(const struct sk_buff *skb, int offset,

end = start + skb_frag_size(frag);
if ((copy = end - offset) > 0) {
+ struct page *page = skb_frag_page(frag);
+ u8 *vaddr = kmap(page);
+
if (copy > len)
copy = len;
- n = copy_page_to_iter(skb_frag_page(frag),
- frag->page_offset + offset -
- start, copy, to);
+ n = copy_to_iter(vaddr + frag->page_offset +
+ offset - start, copy, to);
+ kunmap(page);
offset += n;
if (n != copy)
goto short_copy;
--
2.17.1