path: root/io_uring/net.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/file.h>
#include <linux/slab.h>
#include <linux/net.h>
#include <linux/compat.h>
#include <net/compat.h>
#include <linux/io_uring.h>

#include <uapi/linux/io_uring.h>

#include "io_uring.h"
#include "kbuf.h"
#include "alloc_cache.h"
#include "net.h"

#if defined(CONFIG_NET)
struct io_shutdown {
	struct file			*file;
	int				how;
};

struct io_accept {
	struct file			*file;
	struct sockaddr __user		*addr;
	int __user			*addr_len;
	int				flags;
	u32				file_slot;
	unsigned long			nofile;
};

struct io_socket {
	struct file			*file;
	int				domain;
	int				type;
	int				protocol;
	int				flags;
	u32				file_slot;
	unsigned long			nofile;
};

struct io_connect {
	struct file			*file;
	struct sockaddr __user		*addr;
	int				addr_len;
};

struct io_sr_msg {
	struct file			*file;
	union {
		struct compat_msghdr __user	*umsg_compat;
		struct user_msghdr __user	*umsg;
		void __user			*buf;
	};
	int				msg_flags;
	size_t				len;
	size_t				done_io;
	unsigned int			flags;
};

#define IO_APOLL_MULTI_POLLED (REQ_F_APOLL_MULTISHOT | REQ_F_POLLED)

int io_shutdown_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
	struct io_shutdown *shutdown = io_kiocb_to_cmd(req);

	if (unlikely(sqe->off || sqe->addr || sqe->rw_flags ||
		     sqe->buf_index || sqe->splice_fd_in))
		return -EINVAL;

	shutdown->how = READ_ONCE(sqe->len);
	return 0;
}

int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
{
	struct io_shutdown *shutdown = io_kiocb_to_cmd(req);
	struct socket *sock;
	int ret;

	if (issue_flags & IO_URING_F_NONBLOCK)
		return -EAGAIN;

	sock = sock_from_file(req->file);
	if (unlikely(!sock))
		return -ENOTSOCK;

	ret = __sys_shutdown_sock(sock, shutdown->how);
	io_req_set_res(req, ret, 0);
	return IOU_OK;
}

static bool io_net_retry(struct socket *sock, int flags)
{
	if (!(flags & MSG_WAITALL))
		return false;
	return sock->type == SOCK_STREAM || sock->type == SOCK_SEQPACKET;
}

static void io_netmsg_recycle(struct io_kiocb *req, unsigned int issue_flags)
{
	struct io_async_msghdr *hdr = req->async_data;

	if (!hdr || issue_flags & IO_URING_F_UNLOCKED)
		return;

	/* Let normal cleanup path reap it if we fail adding to the cache */
	if (io_alloc_cache_put(&req->ctx->netmsg_cache, &hdr->cache)) {
		req->async_data = NULL;
		req->flags &= ~REQ_F_ASYNC_DATA;
	}
}

static struct io_async_msghdr *io_recvmsg_alloc_async(struct io_kiocb *req,
						      unsigned int issue_flags)
{
	struct io_ring_ctx *ctx = req->ctx;
	struct io_cache_entry *entry;

	if (!(issue_flags & IO_URING_F_UNLOCKED) &&
	    (entry = io_alloc_cache_get(&ctx->netmsg_cache)) != NULL) {
		struct io_async_msghdr *hdr;

		hdr = container_of(entry, struct io_async_msghdr, cache);
		req->flags |= REQ_F_ASYNC_DATA;
		req->async_data = hdr;
		return hdr;
	}

	if (!io_alloc_async_data(req))
		return req->async_data;

	return NULL;
}

static int io_setup_async_msg(struct io_kiocb *req,
			      struct io_async_msghdr *kmsg,
			      unsigned int issue_flags)
{
	struct io_async_msghdr *async_msg = req->async_data;

	if (async_msg)
		return -EAGAIN;
	async_msg = io_recvmsg_alloc_async(req, issue_flags);
	if (!async_msg) {
		kfree(kmsg->free_iov);
		return -ENOMEM;
	}
	req->flags |= REQ_F_NEED_CLEANUP;
	memcpy(async_msg, kmsg, sizeof(*kmsg));
	async_msg->msg.msg_name = &async_msg->addr;
	/* if were using fast_iov, set it to the new one */
	if (!async_msg->free_iov)
		async_msg->msg.msg_iter.iov = async_msg->fast_iov;

	return -EAGAIN;
}

static int io_sendmsg_copy_hdr(struct io_kiocb *req,
			       struct io_async_msghdr *iomsg)
{
	struct io_sr_msg *sr = io_kiocb_to_cmd(req);

	iomsg->msg.msg_name = &iomsg->addr;
	iomsg->free_iov = iomsg->fast_iov;
	return sendmsg_copy_msghdr(&iomsg->msg, sr->umsg, sr->msg_flags,
					&iomsg->free_iov);
}

int io_sendmsg_prep_async(struct io_kiocb *req)