[PATCH net-next v4 21/27] io_uring: allow to pass addr into sendzc

Pavel Begunkov
2022-07-07T11:53:14Z

Allow to specify an address to zerocopy sends making it more like
sendto(2).

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
include/uapi/linux/io_uring.h | 2 +-
io_uring/net.c | 18 ++++++++++++++++--
2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index a6844908772a..25278c9ac6d2 100644
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -65,7 +65,7 @@ struct io_uring_sqe {
__u32 file_index;
struct {
__u16 notification_idx;
- __u16 __pad;
+ __u16 addr_len;
};
};
union {
diff --git a/io_uring/net.c b/io_uring/net.c
index 69273d4f4ef0..2172cf3facd8 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -66,6 +66,8 @@ struct io_sendzc {
u16 slot_idx;
unsigned msg_flags;
unsigned flags;
+ unsigned addr_len;
+ void __user *addr;
};

#define IO_APOLL_MULTI_POLLED (REQ_F_APOLL_MULTISHOT | REQ_F_POLLED)
@@ -666,8 +668,7 @@ int io_sendzc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
struct io_sendzc *zc = io_kiocb_to_cmd(req);

- if (READ_ONCE(sqe->addr2) || READ_ONCE(sqe->__pad2[0]) ||
- READ_ONCE(sqe->addr3))
+ if (READ_ONCE(sqe->__pad2[0]) || READ_ONCE(sqe->addr3))
return -EINVAL;

zc->flags = READ_ONCE(sqe->ioprio);
@@ -680,6 +681,10 @@ int io_sendzc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
zc->slot_idx = READ_ONCE(sqe->notification_idx);
if (zc->msg_flags & MSG_DONTWAIT)
req->flags |= REQ_F_NOWAIT;
+
+ zc->addr = u64_to_user_ptr(READ_ONCE(sqe->addr2));
+ zc->addr_len = READ_ONCE(sqe->addr_len);
+
#ifdef CONFIG_COMPAT
if (req->ctx->compat)
zc->msg_flags |= MSG_CMSG_COMPAT;
@@ -689,6 +694,7 @@ int io_sendzc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)

int io_sendzc(struct io_kiocb *req, unsigned int issue_flags)
{
+ struct sockaddr_storage address;
struct io_ring_ctx *ctx = req->ctx;
struct io_sendzc *zc = io_kiocb_to_cmd(req);
struct io_notif_slot *notif_slot;
@@ -726,6 +732,14 @@ int io_sendzc(struct io_kiocb *req, unsigned int issue_flags)
return ret;
mm_account_pinned_pages(&notif->uarg.mmp, zc->len);

+ if (zc->addr) {
+ ret = move_addr_to_kernel(zc->addr, zc->addr_len, &address);
+ if (unlikely(ret < 0))
+ return ret;
+ msg.msg_name = (struct sockaddr *)&address;
+ msg.msg_namelen = zc->addr_len;
+ }
+
msg_flags = zc->msg_flags | MSG_ZEROCOPY;
if (issue_flags & IO_URING_F_NONBLOCK)
msg_flags |= MSG_DONTWAIT;
--
2.36.1