mirror of https://gitee.com/openkylin/linux.git
165 lines
3.3 KiB
C
165 lines
3.3 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/* Copyright (c) 2018, Linaro Ltd */
|
|
|
|
#include <linux/miscdevice.h>
|
|
#include <linux/module.h>
|
|
#include <linux/poll.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/uaccess.h>
|
|
|
|
#include "qrtr.h"
|
|
|
|
struct qrtr_tun {
|
|
struct qrtr_endpoint ep;
|
|
|
|
struct sk_buff_head queue;
|
|
wait_queue_head_t readq;
|
|
};
|
|
|
|
static int qrtr_tun_send(struct qrtr_endpoint *ep, struct sk_buff *skb)
|
|
{
|
|
struct qrtr_tun *tun = container_of(ep, struct qrtr_tun, ep);
|
|
|
|
skb_queue_tail(&tun->queue, skb);
|
|
|
|
/* wake up any blocking processes, waiting for new data */
|
|
wake_up_interruptible(&tun->readq);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int qrtr_tun_open(struct inode *inode, struct file *filp)
|
|
{
|
|
struct qrtr_tun *tun;
|
|
|
|
tun = kzalloc(sizeof(*tun), GFP_KERNEL);
|
|
if (!tun)
|
|
return -ENOMEM;
|
|
|
|
skb_queue_head_init(&tun->queue);
|
|
init_waitqueue_head(&tun->readq);
|
|
|
|
tun->ep.xmit = qrtr_tun_send;
|
|
|
|
filp->private_data = tun;
|
|
|
|
return qrtr_endpoint_register(&tun->ep, QRTR_EP_NID_AUTO);
|
|
}
|
|
|
|
static ssize_t qrtr_tun_read_iter(struct kiocb *iocb, struct iov_iter *to)
|
|
{
|
|
struct file *filp = iocb->ki_filp;
|
|
struct qrtr_tun *tun = filp->private_data;
|
|
struct sk_buff *skb;
|
|
int count;
|
|
|
|
while (!(skb = skb_dequeue(&tun->queue))) {
|
|
if (filp->f_flags & O_NONBLOCK)
|
|
return -EAGAIN;
|
|
|
|
/* Wait until we get data or the endpoint goes away */
|
|
if (wait_event_interruptible(tun->readq,
|
|
!skb_queue_empty(&tun->queue)))
|
|
return -ERESTARTSYS;
|
|
}
|
|
|
|
count = min_t(size_t, iov_iter_count(to), skb->len);
|
|
if (copy_to_iter(skb->data, count, to) != count)
|
|
count = -EFAULT;
|
|
|
|
kfree_skb(skb);
|
|
|
|
return count;
|
|
}
|
|
|
|
static ssize_t qrtr_tun_write_iter(struct kiocb *iocb, struct iov_iter *from)
|
|
{
|
|
struct file *filp = iocb->ki_filp;
|
|
struct qrtr_tun *tun = filp->private_data;
|
|
size_t len = iov_iter_count(from);
|
|
ssize_t ret;
|
|
void *kbuf;
|
|
|
|
kbuf = kzalloc(len, GFP_KERNEL);
|
|
if (!kbuf)
|
|
return -ENOMEM;
|
|
|
|
if (!copy_from_iter_full(kbuf, len, from)) {
|
|
kfree(kbuf);
|
|
return -EFAULT;
|
|
}
|
|
|
|
ret = qrtr_endpoint_post(&tun->ep, kbuf, len);
|
|
|
|
kfree(kbuf);
|
|
return ret < 0 ? ret : len;
|
|
}
|
|
|
|
static __poll_t qrtr_tun_poll(struct file *filp, poll_table *wait)
|
|
{
|
|
struct qrtr_tun *tun = filp->private_data;
|
|
__poll_t mask = 0;
|
|
|
|
poll_wait(filp, &tun->readq, wait);
|
|
|
|
if (!skb_queue_empty(&tun->queue))
|
|
mask |= EPOLLIN | EPOLLRDNORM;
|
|
|
|
return mask;
|
|
}
|
|
|
|
static int qrtr_tun_release(struct inode *inode, struct file *filp)
|
|
{
|
|
struct qrtr_tun *tun = filp->private_data;
|
|
struct sk_buff *skb;
|
|
|
|
qrtr_endpoint_unregister(&tun->ep);
|
|
|
|
/* Discard all SKBs */
|
|
while (!skb_queue_empty(&tun->queue)) {
|
|
skb = skb_dequeue(&tun->queue);
|
|
kfree_skb(skb);
|
|
}
|
|
|
|
kfree(tun);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct file_operations qrtr_tun_ops = {
|
|
.owner = THIS_MODULE,
|
|
.open = qrtr_tun_open,
|
|
.poll = qrtr_tun_poll,
|
|
.read_iter = qrtr_tun_read_iter,
|
|
.write_iter = qrtr_tun_write_iter,
|
|
.release = qrtr_tun_release,
|
|
};
|
|
|
|
static struct miscdevice qrtr_tun_miscdev = {
|
|
MISC_DYNAMIC_MINOR,
|
|
"qrtr-tun",
|
|
&qrtr_tun_ops,
|
|
};
|
|
|
|
static int __init qrtr_tun_init(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = misc_register(&qrtr_tun_miscdev);
|
|
if (ret)
|
|
pr_err("failed to register Qualcomm IPC Router tun device\n");
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void __exit qrtr_tun_exit(void)
|
|
{
|
|
misc_deregister(&qrtr_tun_miscdev);
|
|
}
|
|
|
|
module_init(qrtr_tun_init);
|
|
module_exit(qrtr_tun_exit);
|
|
|
|
MODULE_DESCRIPTION("Qualcomm IPC Router TUN device");
|
|
MODULE_LICENSE("GPL v2");
|