[PATCH v3 27/55] tls/device: Support MSG_SPLICE_PAGES
From: David Howells <dhowells@redhat.com>
Date: 2023-03-31 16:15:24
Also in:
linux-fsdevel, linux-mm, lkml
Subsystem:
networking [general], networking [tls], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, John Fastabend, Sabrina Dubroca, Linus Torvalds
Make TLS's device sendmsg() support MSG_SPLICE_PAGES. This causes pages to be spliced from the source iterator if possible and copied the data if not. 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: Chuck Lever <redacted> cc: Boris Pismenny <borisp@nvidia.com> cc: John Fastabend <john.fastabend@gmail.com> cc: Jakub Kicinski <kuba@kernel.org> cc: Eric Dumazet <edumazet@google.com> cc: "David S. Miller" <davem@davemloft.net> cc: Paolo Abeni <pabeni@redhat.com> cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> cc: netdev@vger.kernel.org --- net/tls/tls_device.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+)
diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index 6c593788dc25..f5c3b56ac1ce 100644
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c@@ -508,7 +508,30 @@ static int tls_push_data(struct sock *sk, zc_pfrag.offset = iter_offset.offset; zc_pfrag.size = copy; tls_append_frag(record, &zc_pfrag, copy); + } else if (copy && (flags & MSG_SPLICE_PAGES)) { + struct page_frag zc_pfrag; + struct page **pages = &zc_pfrag.page; + size_t off; + + rc = iov_iter_extract_pages(iter_offset.msg_iter, &pages, + copy, 1, 0, &off); + if (rc <= 0) { + if (rc == 0) + rc = -EIO; + goto handle_error; + } + copy = rc; + + if (!sendpage_ok(zc_pfrag.page)) { + iov_iter_revert(iter_offset.msg_iter, copy); + goto no_zcopy_this_page; + } + + zc_pfrag.offset = off; + zc_pfrag.size = copy; + tls_append_frag(record, &zc_pfrag, copy); } else if (copy) { +no_zcopy_this_page: copy = min_t(size_t, copy, pfrag->size - pfrag->offset); rc = tls_device_copy_data(page_address(pfrag->page) +
@@ -571,6 +594,9 @@ int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) union tls_iter_offset iter; int rc; + if (!tls_ctx->zerocopy_sendfile) + msg->msg_flags &= ~MSG_SPLICE_PAGES; + mutex_lock(&tls_ctx->tx_lock); lock_sock(sk);