[PATCH net-next 10/12] tls/sw: Convert tls_sw_sendpage() to use MSG_SPLICE_PAGES
From: David Howells <dhowells@redhat.com>
Date: 2023-05-24 15:36:41
Also in:
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
Convert tls_sw_sendpage() and tls_sw_sendpage_locked() to use sendmsg()
with MSG_SPLICE_PAGES rather than directly splicing in the pages itself.
[!] Note that tls_sw_sendpage_locked() appears to have the wrong locking
upstream. I think the caller will only hold the socket lock, but it
should hold tls_ctx->tx_lock too.
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_sw.c | 164 +++++++++--------------------------------------
1 file changed, 30 insertions(+), 134 deletions(-)
diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
index 0ccef8aa9951..1a5926cc3e84 100644
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c@@ -972,7 +972,7 @@ static int rls_sw_sendmsg_splice(struct sock *sk, struct msghdr *msg, return 0; } -int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) +static int tls_sw_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) { long timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); struct tls_context *tls_ctx = tls_get_ctx(sk);
@@ -995,15 +995,6 @@ int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) int ret = 0; int pending; - if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | - MSG_CMSG_COMPAT)) - return -EOPNOTSUPP; - - ret = mutex_lock_interruptible(&tls_ctx->tx_lock); - if (ret) - return ret; - lock_sock(sk); - if (unlikely(msg->msg_controllen)) { ret = tls_process_cmsg(sk, msg, &record_type); if (ret) {
@@ -1204,157 +1195,62 @@ int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) send_end: ret = sk_stream_error(sk, msg->msg_flags, ret); - - release_sock(sk); - mutex_unlock(&tls_ctx->tx_lock); return copied > 0 ? copied : ret; } -static int tls_sw_do_sendpage(struct sock *sk, struct page *page, - int offset, size_t size, int flags) +int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) { - long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); struct tls_context *tls_ctx = tls_get_ctx(sk); - struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); - struct tls_prot_info *prot = &tls_ctx->prot_info; - unsigned char record_type = TLS_RECORD_TYPE_DATA; - struct sk_msg *msg_pl; - struct tls_rec *rec; - int num_async = 0; - ssize_t copied = 0; - bool full_record; - int record_room; - int ret = 0; - bool eor; - - eor = !(flags & MSG_SENDPAGE_NOTLAST); - sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); - - /* Call the sk_stream functions to manage the sndbuf mem. */ - while (size > 0) { - size_t copy, required_size; - - if (sk->sk_err) { - ret = -sk->sk_err; - goto sendpage_end; - } - - if (ctx->open_rec) - rec = ctx->open_rec; - else - rec = ctx->open_rec = tls_get_rec(sk); - if (!rec) { - ret = -ENOMEM; - goto sendpage_end; - } - - msg_pl = &rec->msg_plaintext; - - full_record = false; - record_room = TLS_MAX_PAYLOAD_SIZE - msg_pl->sg.size; - copy = size; - if (copy >= record_room) { - copy = record_room; - full_record = true; - } - - required_size = msg_pl->sg.size + copy + prot->overhead_size; - - if (!sk_stream_memory_free(sk)) - goto wait_for_sndbuf; -alloc_payload: - ret = tls_alloc_encrypted_msg(sk, required_size); - if (ret) { - if (ret != -ENOSPC) - goto wait_for_memory; - - /* Adjust copy according to the amount that was - * actually allocated. The difference is due - * to max sg elements limit - */ - copy -= required_size - msg_pl->sg.size; - full_record = true; - } - - sk_msg_page_add(msg_pl, page, copy, offset); - sk_mem_charge(sk, copy); - - offset += copy; - size -= copy; - copied += copy; - - tls_ctx->pending_open_record_frags = true; - if (full_record || eor || sk_msg_full(msg_pl)) { - ret = bpf_exec_tx_verdict(msg_pl, sk, full_record, - record_type, &copied, flags); - if (ret) { - if (ret == -EINPROGRESS) - num_async++; - else if (ret == -ENOMEM) - goto wait_for_memory; - else if (ret != -EAGAIN) { - if (ret == -ENOSPC) - ret = 0; - goto sendpage_end; - } - } - } - continue; -wait_for_sndbuf: - set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); -wait_for_memory: - ret = sk_stream_wait_memory(sk, &timeo); - if (ret) { - if (ctx->open_rec) - tls_trim_both_msgs(sk, msg_pl->sg.size); - goto sendpage_end; - } + int ret; - if (ctx->open_rec) - goto alloc_payload; - } + if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | + MSG_CMSG_COMPAT | MSG_SPLICE_PAGES | + MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY)) + return -EOPNOTSUPP; - if (num_async) { - /* Transmit if any encryptions have completed */ - if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) { - cancel_delayed_work(&ctx->tx_work.work); - tls_tx_records(sk, flags); - } - } -sendpage_end: - ret = sk_stream_error(sk, flags, ret); - return copied > 0 ? copied : ret; + ret = mutex_lock_interruptible(&tls_ctx->tx_lock); + if (ret) + return ret; + lock_sock(sk); + ret = tls_sw_sendmsg_locked(sk, msg, size); + release_sock(sk); + mutex_unlock(&tls_ctx->tx_lock); + return ret; } int tls_sw_sendpage_locked(struct sock *sk, struct page *page, int offset, size_t size, int flags) { + struct bio_vec bvec; + struct msghdr msg = { .msg_flags = flags | MSG_SPLICE_PAGES, }; + if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY | MSG_NO_SHARED_FRAGS)) return -EOPNOTSUPP; + if (flags & MSG_SENDPAGE_NOTLAST) + msg.msg_flags |= MSG_MORE; - return tls_sw_do_sendpage(sk, page, offset, size, flags); + bvec_set_page(&bvec, page, size, offset); + iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, size); + return tls_sw_sendmsg_locked(sk, &msg, size); } int tls_sw_sendpage(struct sock *sk, struct page *page, int offset, size_t size, int flags) { - struct tls_context *tls_ctx = tls_get_ctx(sk); - int ret; + struct bio_vec bvec; + struct msghdr msg = { .msg_flags = flags | MSG_SPLICE_PAGES, }; if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY)) return -EOPNOTSUPP; + if (flags & MSG_SENDPAGE_NOTLAST) + msg.msg_flags |= MSG_MORE; - ret = mutex_lock_interruptible(&tls_ctx->tx_lock); - if (ret) - return ret; - lock_sock(sk); - ret = tls_sw_do_sendpage(sk, page, offset, size, flags); - release_sock(sk); - mutex_unlock(&tls_ctx->tx_lock); - return ret; + bvec_set_page(&bvec, page, size, offset); + iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, size); + return tls_sw_sendmsg(sk, &msg, size); } static int