lkml.org 
[lkml]   [2023]   [May]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH net-next v8 11/16] ip, udp: Support MSG_SPLICE_PAGES
Date
Make IP/UDP sendmsg() support MSG_SPLICE_PAGES.  This causes pages to be
spliced from the source iterator.

This allows ->sendpage() to be replaced by something that can handle
multiple multipage folios in a single transaction.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
cc: David Ahern <dsahern@kernel.org>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Jens Axboe <axboe@kernel.dk>
cc: Matthew Wilcox <willy@infradead.org>
cc: netdev@vger.kernel.org
---

Notes:
ver #6)
- Use common helper.

net/ipv4/ip_output.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)

diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 52fc840898d8..c7db973b5d29 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -1048,6 +1048,14 @@ static int __ip_append_data(struct sock *sk,
skb_zcopy_set(skb, uarg, &extra_uref);
}
}
+ } else if ((flags & MSG_SPLICE_PAGES) && length) {
+ if (inet->hdrincl)
+ return -EPERM;
+ if (rt->dst.dev->features & NETIF_F_SG)
+ /* We need an empty buffer to attach stuff to */
+ paged = true;
+ else
+ flags &= ~MSG_SPLICE_PAGES;
}

cork->length += length;
@@ -1207,6 +1215,15 @@ static int __ip_append_data(struct sock *sk,
err = -EFAULT;
goto error;
}
+ } else if (flags & MSG_SPLICE_PAGES) {
+ struct msghdr *msg = from;
+
+ err = skb_splice_from_iter(skb, &msg->msg_iter, copy,
+ sk->sk_allocation);
+ if (err < 0)
+ goto error;
+ copy = err;
+ wmem_alloc_delta += copy;
} else if (!zc) {
int i = skb_shinfo(skb)->nr_frags;

\
 
 \ /
  Last update: 2023-05-18 13:38    [W:0.127 / U:0.124 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site