On Wed, Jun 14, 2023 at 08:15:10AM -0700, David Ahern wrote:
> On 6/14/23 5:07 AM, Breno Leitao wrote:
> io_uring is just another in-kernel user of sockets. There is no reason
> for io_uring references to be in core net code. It should be using
> exposed in-kernel APIs and doing any translation of its op codes in
> io_uring/ code.
Thanks for the feedback. If we want to keep the network subsystem
untouched, then I we can do it using an approach similar to the
following. Is this a better approach moving forward?
--
From: Breno Leitao <leitao@xxxxxxxxxx>
Date: Mon, 19 Jun 2023 03:37:40 -0700
Subject: [RFC PATCH v2] io_uring: add initial io_uring_cmd support for sockets
Enable io_uring command operations on sockets. Create two
SOCKET_URING_OP commands that will operate on sockets.
For that, use the file_operations->uring_cmd callback, and map it to a
uring socket callback, which handles the SOCKET_URING_OP accordingly.
Signed-off-by: Breno Leitao <leitao@xxxxxxxxxx>
---
include/linux/io_uring.h | 6 ++++++
include/uapi/linux/io_uring.h | 8 ++++++++
io_uring/uring_cmd.c | 27 +++++++++++++++++++++++++++
net/socket.c | 2 ++
4 files changed, 43 insertions(+)
diff --git a/include/linux/io_uring.h b/include/linux/io_uring.h
index 7fe31b2cd02f..d1b20e2a9fb0 100644
--- a/include/linux/io_uring.h
+++ b/include/linux/io_uring.h
@@ -71,6 +71,7 @@ static inline void io_uring_free(struct task_struct *tsk)
if (tsk->io_uring)
__io_uring_free(tsk);
}
+int uring_sock_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags);
#else
static inline int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
struct iov_iter *iter, void *ioucmd)
@@ -102,6 +103,11 @@ static inline const char *io_uring_get_opcode(u8 opcode)
{
return "";
}
+static inline int uring_sock_cmd(struct io_uring_cmd *cmd,
+ unsigned int issue_flags)
+{
+ return -EOPNOTSUPP;
+}
#endif
#endif
diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index 0716cb17e436..d93a5ee7d984 100644
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -703,6 +703,14 @@ struct io_uring_recvmsg_out {
__u32 flags;
};
+/*
+ * Argument for IORING_OP_URING_CMD when file is a socket
+ */
+enum {
+ SOCKET_URING_OP_SIOCINQ = 0,
+ SOCKET_URING_OP_SIOCOUTQ,
+};
+
#ifdef __cplusplus
}
#endif
diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c
index 5e32db48696d..dcbe6493b03f 100644
--- a/io_uring/uring_cmd.c
+++ b/io_uring/uring_cmd.c
@@ -7,6 +7,7 @@
#include <linux/nospec.h>
#include <uapi/linux/io_uring.h>
+#include <uapi/asm-generic/ioctls.h>
#include "io_uring.h"
#include "rsrc.h"
@@ -156,3 +157,29 @@ int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
return io_import_fixed(rw, iter, req->imu, ubuf, len);
}
EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed);
+
+int uring_sock_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags)
+{
+ struct socket *sock = cmd->file->private_data;
+ struct sock *sk = sock->sk;
+ int ret, arg = 0;
+
+ if (!sk->sk_prot || !sk->sk_prot->ioctl)
+ return -EOPNOTSUPP;
+
+ switch (cmd->sqe->cmd_op) {
+ case SOCKET_URING_OP_SIOCINQ:
+ ret = sk->sk_prot->ioctl(sk, SIOCINQ, &arg);
+ if (ret)
+ return ret;
+ return arg;
+ case SOCKET_URING_OP_SIOCOUTQ:
+ ret = sk->sk_prot->ioctl(sk, SIOCOUTQ, &arg);
+ if (ret)
+ return ret;
+ return arg;
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+EXPORT_SYMBOL_GPL(uring_sock_cmd);
diff --git a/net/socket.c b/net/socket.c
index b778fc03c6e0..db11e94d2259 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -88,6 +88,7 @@
#include <linux/xattr.h>
#include <linux/nospec.h>
#include <linux/indirect_call_wrapper.h>
+#include <linux/io_uring.h>
#include <linux/uaccess.h>
#include <asm/unistd.h>
@@ -159,6 +160,7 @@ static const struct file_operations socket_file_ops = {
#ifdef CONFIG_COMPAT
.compat_ioctl = compat_sock_ioctl,
#endif
+ .uring_cmd = uring_sock_cmd,
.mmap = sock_mmap,
.release = sock_close,
.fasync = sock_fasync,
--
2.34.1
