Commit d2d30a37 authored by Sagi Grimberg's avatar Sagi Grimberg Committed by Paolo Abeni
Browse files

net: allow skb_datagram_iter to be called from any context 



We only use the mapping in a single context, so kmap_local is sufficient
and cheaper. Make sure to use skb_frag_foreach_page as skb frags may
contain compound pages and we need to map page by page.

Reported-by: default avatarkernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202406161539.b5ff7b20-oliver.sang@intel.com


Fixes: 950fcaec ("datagram: consolidate datagram copy to iter helpers")
Signed-off-by: default avatarSagi Grimberg <sagi@grimberg.me>
Link: https://patch.msgid.link/20240626100008.831849-1-sagi@grimberg.me


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent c93a6f62

net/core/datagram.c

+13 −6
Original line number Diff line number Diff line
@@ -416,15 +416,22 @@ static int __skb_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);

			u32 p_off, p_len, copied;

			struct page *p;

			u8 *vaddr;



			if (copy > len)

				copy = len;



			skb_frag_foreach_page(frag,

					      skb_frag_off(frag) + offset - start,

					      copy, p, p_off, p_len, copied) {

				vaddr = kmap_local_page(p);

				n = INDIRECT_CALL_1(cb, simple_copy_to_iter,

					vaddr + skb_frag_off(frag) + offset - start,

					copy, data, to);

			kunmap(page);

					vaddr + p_off, p_len, data, to);

				kunmap_local(vaddr);

			}



			offset += n;

			if (n != copy)

				goto short_copy;