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

[Sagi Grimberg]

From: Sagi Grimberg <s...@lightbitslabs.com>

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 <da...@davemloft.net>
Signed-off-by: Sagi Grimberg <s...@lightbitslabs.com>
---
 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