io_uring: add support for sendmsg()

This is done through IORING_OP_SENDMSG. There's a new sqe->msg_flags
for the flags argument, and the msghdr struct is passed in the
sqe->addr field.

We use MSG_DONTWAIT to force an inline fast path if sendmsg() doesn't
block, and punt to async execution if it would have.

Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2019-04-19 13:34:07 -06:00
parent 9e645e1105
commit 0fa03c624d
4 changed files with 53 additions and 0 deletions

View File

@ -1390,6 +1390,43 @@ static int io_sync_file_range(struct io_kiocb *req,
return 0;
}
static int io_sendmsg(struct io_kiocb *req, const struct io_uring_sqe *sqe,
bool force_nonblock)
{
#if defined(CONFIG_NET)
struct socket *sock;
int ret;
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
return -EINVAL;
sock = sock_from_file(req->file, &ret);
if (sock) {
struct user_msghdr __user *msg;
unsigned flags;
flags = READ_ONCE(sqe->msg_flags);
if (flags & MSG_DONTWAIT)
req->flags |= REQ_F_NOWAIT;
else if (force_nonblock)
flags |= MSG_DONTWAIT;
msg = (struct user_msghdr __user *) (unsigned long)
READ_ONCE(sqe->addr);
ret = __sys_sendmsg_sock(sock, msg, flags);
if (force_nonblock && ret == -EAGAIN)
return ret;
}
io_cqring_add_event(req->ctx, sqe->user_data, ret);
io_put_req(req);
return 0;
#else
return -EOPNOTSUPP;
#endif
}
static void io_poll_remove_one(struct io_kiocb *req)
{
struct io_poll_iocb *poll = &req->poll;
@ -1675,6 +1712,9 @@ static int __io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
case IORING_OP_SYNC_FILE_RANGE:
ret = io_sync_file_range(req, s->sqe, force_nonblock);
break;
case IORING_OP_SENDMSG:
ret = io_sendmsg(req, s->sqe, force_nonblock);
break;
default:
ret = -EINVAL;
break;

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@ -12,6 +12,7 @@
struct pid;
struct cred;
struct socket;
#define __sockaddr_check_size(size) \
BUILD_BUG_ON(((size) > sizeof(struct __kernel_sockaddr_storage)))
@ -374,6 +375,9 @@ extern int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg,
extern int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg,
unsigned int vlen, unsigned int flags,
bool forbid_cmsg_compat);
extern long __sys_sendmsg_sock(struct socket *sock,
struct user_msghdr __user *msg,
unsigned int flags);
/* helpers which do the actual work for syscalls */
extern int __sys_recvfrom(int fd, void __user *ubuf, size_t size,

View File

@ -27,6 +27,7 @@ struct io_uring_sqe {
__u32 fsync_flags;
__u16 poll_events;
__u32 sync_range_flags;
__u32 msg_flags;
};
__u64 user_data; /* data to be passed back at completion time */
union {
@ -58,6 +59,7 @@ struct io_uring_sqe {
#define IORING_OP_POLL_ADD 6
#define IORING_OP_POLL_REMOVE 7
#define IORING_OP_SYNC_FILE_RANGE 8
#define IORING_OP_SENDMSG 9
/*
* sqe->fsync_flags

View File

@ -2313,6 +2313,13 @@ out_freeiov:
/*
* BSD sendmsg interface
*/
long __sys_sendmsg_sock(struct socket *sock, struct user_msghdr __user *msg,
unsigned int flags)
{
struct msghdr msg_sys;
return ___sys_sendmsg(sock, msg, &msg_sys, flags, NULL, 0);
}
long __sys_sendmsg(int fd, struct user_msghdr __user *msg, unsigned int flags,
bool forbid_cmsg_compat)