CONNECTOR: add a proc entry to list connectors

I got a problem when I wanted to check if the kernel supports process
event connector, and It seems there's no way to do this check.

At best I can check if the kernel supports connector or not, by looking
into /proc/net/netlink, or maybe checking the return value of bind() to
see if it's ENOENT.

So it would be useful to add /proc/net/connector to list all supported
connectors:
 # cat /proc/net/connector
 Name            ID
 connector       4294967295:4294967295
 cn_proc         1:1
 w1              3:1

Changelog:
- fix memory leak: s/seq_release/single_release
- use spin_lock_bh instead of spin_lock_irqsave

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Li Zefan 2008-06-27 20:03:24 -07:00 committed by David S. Miller
parent 10b595aff1
commit a0a61a604c

View file

@ -27,6 +27,8 @@
#include <linux/moduleparam.h>
#include <linux/connector.h>
#include <linux/mutex.h>
#include <linux/proc_fs.h>
#include <linux/spinlock.h>
#include <net/sock.h>
@ -403,6 +405,40 @@ static void cn_callback(void *data)
mutex_unlock(&notify_lock);
}
static int cn_proc_show(struct seq_file *m, void *v)
{
struct cn_queue_dev *dev = cdev.cbdev;
struct cn_callback_entry *cbq;
seq_printf(m, "Name ID\n");
spin_lock_bh(&dev->queue_lock);
list_for_each_entry(cbq, &dev->queue_list, callback_entry) {
seq_printf(m, "%-15s %u:%u\n",
cbq->id.name,
cbq->id.id.idx,
cbq->id.id.val);
}
spin_unlock_bh(&dev->queue_lock);
return 0;
}
static int cn_proc_open(struct inode *inode, struct file *file)
{
return single_open(file, cn_proc_show, NULL);
}
static const struct file_operations cn_file_ops = {
.owner = THIS_MODULE,
.open = cn_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release
};
static int __devinit cn_init(void)
{
struct cn_dev *dev = &cdev;
@ -434,6 +470,8 @@ static int __devinit cn_init(void)
return -EINVAL;
}
proc_net_fops_create(&init_net, "connector", S_IRUGO, &cn_file_ops);
return 0;
}
@ -443,6 +481,8 @@ static void __devexit cn_fini(void)
cn_already_initialized = 0;
proc_net_remove(&init_net, "connector");
cn_del_callback(&dev->id);
cn_queue_free_dev(dev->cbdev);
netlink_kernel_release(dev->nls);