tls/device: Convert tls_device_sendpage() to use MSG_SPLICE_PAGES

Convert tls_device_sendpage() to use sendmsg() with MSG_SPLICE_PAGES rather
than directly splicing in the pages itself.  With that, the tls_iter_offset
union is no longer necessary and can be replaced with an iov_iter pointer
and the zc_page argument to tls_push_data() can also be removed.

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>
Acked-by: Jakub Kicinski <kuba@kernel.org>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Boris Pismenny <borisp@nvidia.com>
cc: John Fastabend <john.fastabend@gmail.com>
cc: Jens Axboe <axboe@kernel.dk>
cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index bb3bb52..b4864d5 100644 (file)
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -422,16 +422,10 @@ static int tls_device_copy_data(void *addr, size_t bytes, struct iov_iter *i)
        return 0;
 }
 
-union tls_iter_offset {
-       struct iov_iter *msg_iter;
-       int offset;
-};
-
 static int tls_push_data(struct sock *sk,
-                        union tls_iter_offset iter_offset,
+                        struct iov_iter *iter,
                         size_t size, int flags,
-                        unsigned char record_type,
-                        struct page *zc_page)
+                        unsigned char record_type)
 {
        struct tls_context *tls_ctx = tls_get_ctx(sk);
        struct tls_prot_info *prot = &tls_ctx->prot_info;
@@ -500,22 +494,13 @@ handle_error:
                record = ctx->open_record;
 
                copy = min_t(size_t, size, max_open_record_len - record->len);
-               if (copy && zc_page) {
-                       struct page_frag zc_pfrag;
-
-                       zc_pfrag.page = zc_page;
-                       zc_pfrag.offset = iter_offset.offset;
-                       zc_pfrag.size = copy;
-                       tls_append_frag(record, &zc_pfrag, copy);
-
-                       iter_offset.offset += copy;
-               } else if (copy && (flags & MSG_SPLICE_PAGES)) {
+               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);
+                       rc = iov_iter_extract_pages(iter, &pages,
+                                                   copy, 1, 0, &off);
                        if (rc <= 0) {
                                if (rc == 0)
                                        rc = -EIO;
@@ -524,7 +509,7 @@ handle_error:
                        copy = rc;
 
                        if (WARN_ON_ONCE(!sendpage_ok(zc_pfrag.page))) {
-                               iov_iter_revert(iter_offset.msg_iter, copy);
+                               iov_iter_revert(iter, copy);
                                rc = -EIO;
                                goto handle_error;
                        }
@@ -537,7 +522,7 @@ handle_error:
 
                        rc = tls_device_copy_data(page_address(pfrag->page) +
                                                  pfrag->offset, copy,
-                                                 iter_offset.msg_iter);
+                                                 iter);
                        if (rc)
                                goto handle_error;
                        tls_append_frag(record, pfrag, copy);
@@ -592,7 +577,6 @@ int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 {
        unsigned char record_type = TLS_RECORD_TYPE_DATA;
        struct tls_context *tls_ctx = tls_get_ctx(sk);
-       union tls_iter_offset iter;
        int rc;
 
        if (!tls_ctx->zerocopy_sendfile)
@@ -607,8 +591,8 @@ int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
                        goto out;
        }
 
-       iter.msg_iter = &msg->msg_iter;
-       rc = tls_push_data(sk, iter, size, msg->msg_flags, record_type, NULL);
+       rc = tls_push_data(sk, &msg->msg_iter, size, msg->msg_flags,
+                          record_type);
 
 out:
        release_sock(sk);
@@ -620,8 +604,7 @@ void tls_device_splice_eof(struct socket *sock)
 {
        struct sock *sk = sock->sk;
        struct tls_context *tls_ctx = tls_get_ctx(sk);
-       union tls_iter_offset iter;
-       struct iov_iter iov_iter = {};
+       struct iov_iter iter = {};
 
        if (!tls_is_partially_sent_record(tls_ctx))
                return;
@@ -630,9 +613,8 @@ void tls_device_splice_eof(struct socket *sock)
        lock_sock(sk);
 
        if (tls_is_partially_sent_record(tls_ctx)) {
-               iov_iter_bvec(&iov_iter, ITER_SOURCE, NULL, 0, 0);
-               iter.msg_iter = &iov_iter;
-               tls_push_data(sk, iter, 0, 0, TLS_RECORD_TYPE_DATA, NULL);
+               iov_iter_bvec(&iter, ITER_SOURCE, NULL, 0, 0);
+               tls_push_data(sk, &iter, 0, 0, TLS_RECORD_TYPE_DATA);
        }
 
        release_sock(sk);
@@ -642,44 +624,18 @@ void tls_device_splice_eof(struct socket *sock)
 int tls_device_sendpage(struct sock *sk, struct page *page,
                        int offset, size_t size, int flags)
 {
-       struct tls_context *tls_ctx = tls_get_ctx(sk);
-       union tls_iter_offset iter_offset;
-       struct iov_iter msg_iter;
-       char *kaddr;
-       struct kvec iov;
-       int rc;
+       struct bio_vec bvec;
+       struct msghdr msg = { .msg_flags = flags | MSG_SPLICE_PAGES, };
 
        if (flags & MSG_SENDPAGE_NOTLAST)
-               flags |= MSG_MORE;
-
-       mutex_lock(&tls_ctx->tx_lock);
-       lock_sock(sk);
+               msg.msg_flags |= MSG_MORE;
 
-       if (flags & MSG_OOB) {
-               rc = -EOPNOTSUPP;
-               goto out;
-       }
-
-       if (tls_ctx->zerocopy_sendfile) {
-               iter_offset.offset = offset;
-               rc = tls_push_data(sk, iter_offset, size,
-                                  flags, TLS_RECORD_TYPE_DATA, page);
-               goto out;
-       }
-
-       kaddr = kmap(page);
-       iov.iov_base = kaddr + offset;
-       iov.iov_len = size;
-       iov_iter_kvec(&msg_iter, ITER_SOURCE, &iov, 1, size);
-       iter_offset.msg_iter = &msg_iter;
-       rc = tls_push_data(sk, iter_offset, size, flags, TLS_RECORD_TYPE_DATA,
-                          NULL);
-       kunmap(page);
+       if (flags & MSG_OOB)
+               return -EOPNOTSUPP;
 
-out:
-       release_sock(sk);
-       mutex_unlock(&tls_ctx->tx_lock);
-       return rc;
+       bvec_set_page(&bvec, page, size, offset);
+       iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, size);
+       return tls_device_sendmsg(sk, &msg, size);
 }
 
 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context,
@@ -744,12 +700,10 @@ EXPORT_SYMBOL(tls_get_record);
 
 static int tls_device_push_pending_record(struct sock *sk, int flags)
 {
-       union tls_iter_offset iter;
-       struct iov_iter msg_iter;
+       struct iov_iter iter;
 
-       iov_iter_kvec(&msg_iter, ITER_SOURCE, NULL, 0, 0);
-       iter.msg_iter = &msg_iter;
-       return tls_push_data(sk, iter, 0, flags, TLS_RECORD_TYPE_DATA, NULL);
+       iov_iter_kvec(&iter, ITER_SOURCE, NULL, 0, 0);
+       return tls_push_data(sk, &iter, 0, flags, TLS_RECORD_TYPE_DATA);
 }
 
 void tls_device_write_space(struct sock *sk, struct tls_context *ctx)