/*
* connector.c
- *
- * 2004-2005 Copyright (c) Evgeniy Polyakov <johnpol@2ka.mipt.ru>
+ *
+ * 2004+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net>
* All rights reserved.
- *
+ *
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
#include <linux/netlink.h>
#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>
MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>");
+MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>");
MODULE_DESCRIPTION("Generic userspace <-> kernelspace connector.");
static u32 cn_idx = CN_IDX_CONNECTOR;
MODULE_PARM_DESC(cn_idx, "Connector's main device idx.");
MODULE_PARM_DESC(cn_val, "Connector's main device val.");
-static DECLARE_MUTEX(notify_lock);
+static DEFINE_MUTEX(notify_lock);
static LIST_HEAD(notify_list);
static struct cn_dev cdev;
-int cn_already_initialized = 0;
+static int cn_already_initialized;
/*
* msg->seq and msg->ack are used to determine message genealogy.
* a new message.
*
*/
-int cn_netlink_send(struct cn_msg *msg, u32 __group, int gfp_mask)
+int cn_netlink_send(struct cn_msg *msg, u32 __group, gfp_t gfp_mask)
{
struct cn_callback_entry *__cbq;
unsigned int size;
spin_lock_bh(&dev->cbdev->queue_lock);
list_for_each_entry(__cbq, &dev->cbdev->queue_list,
callback_entry) {
- if (cn_cb_equal(&__cbq->cb->id, &msg->id)) {
+ if (cn_cb_equal(&__cbq->id.id, &msg->id)) {
found = 1;
group = __cbq->group;
+ break;
}
}
spin_unlock_bh(&dev->cbdev->queue_lock);
group = __group;
}
+ if (!netlink_has_listeners(dev->nls, group))
+ return -ESRCH;
+
size = NLMSG_SPACE(sizeof(*msg) + msg->len);
skb = alloc_skb(size, gfp_mask);
NETLINK_CB(skb).dst_group = group;
- netlink_broadcast(dev->nls, skb, 0, group, gfp_mask);
-
- return 0;
+ return netlink_broadcast(dev->nls, skb, 0, group, gfp_mask);
nlmsg_failure:
kfree_skb(skb);
return -EINVAL;
}
+EXPORT_SYMBOL_GPL(cn_netlink_send);
/*
* Callback helper - queues work and setup destructor for given data.
*/
-static int cn_call_callback(struct cn_msg *msg, void (*destruct_data)(void *), void *data)
+static int cn_call_callback(struct sk_buff *skb)
{
- struct cn_callback_entry *__cbq;
+ struct cn_callback_entry *__cbq, *__new_cbq;
struct cn_dev *dev = &cdev;
- int found = 0;
+ struct cn_msg *msg = NLMSG_DATA(nlmsg_hdr(skb));
+ int err = -ENODEV;
spin_lock_bh(&dev->cbdev->queue_lock);
list_for_each_entry(__cbq, &dev->cbdev->queue_list, callback_entry) {
- if (cn_cb_equal(&__cbq->cb->id, &msg->id)) {
- /*
- * Let's scream if there is some magic and the
- * data will arrive asynchronously here.
- * [i.e. netlink messages will be queued].
- * After the first warning I will fix it
- * quickly, but now I think it is
- * impossible. --zbr (2004_04_27).
- */
- if (likely(!test_bit(0, &__cbq->work.pending) &&
- __cbq->ddata == NULL)) {
- __cbq->cb->priv = msg;
-
- __cbq->ddata = data;
- __cbq->destruct_data = destruct_data;
-
- if (queue_work(dev->cbdev->cn_queue,
- &__cbq->work))
- found = 1;
+ if (cn_cb_equal(&__cbq->id.id, &msg->id)) {
+ if (likely(!work_pending(&__cbq->work) &&
+ __cbq->data.skb == NULL)) {
+ __cbq->data.skb = skb;
+
+ if (queue_cn_work(__cbq, &__cbq->work))
+ err = 0;
+ else
+ err = -EINVAL;
} else {
- printk("%s: cbq->data=%p, "
- "work->pending=%08lx.\n",
- __func__, __cbq->ddata,
- __cbq->work.pending);
- WARN_ON(1);
+ struct cn_callback_data *d;
+
+ err = -ENOMEM;
+ __new_cbq = kzalloc(sizeof(struct cn_callback_entry), GFP_ATOMIC);
+ if (__new_cbq) {
+ d = &__new_cbq->data;
+ d->skb = skb;
+ d->callback = __cbq->data.callback;
+ d->free = __new_cbq;
+
+ __new_cbq->pdev = __cbq->pdev;
+
+ INIT_WORK(&__new_cbq->work,
+ &cn_queue_wrapper);
+
+ if (queue_cn_work(__new_cbq,
+ &__new_cbq->work))
+ err = 0;
+ else {
+ kfree(__new_cbq);
+ err = -EINVAL;
+ }
+ }
}
break;
}
}
spin_unlock_bh(&dev->cbdev->queue_lock);
- return found ? 0 : -ENODEV;
-}
-
-/*
- * Skb receive helper - checks skb and msg size and calls callback
- * helper.
- */
-static int __cn_rx_skb(struct sk_buff *skb, struct nlmsghdr *nlh)
-{
- u32 pid, uid, seq, group;
- struct cn_msg *msg;
-
- pid = NETLINK_CREDS(skb)->pid;
- uid = NETLINK_CREDS(skb)->uid;
- seq = nlh->nlmsg_seq;
- group = NETLINK_CB((skb)).dst_group;
- msg = NLMSG_DATA(nlh);
-
- return cn_call_callback(msg, (void (*)(void *))kfree_skb, skb);
+ return err;
}
/*
* Main netlink receiving function.
*
- * It checks skb and netlink header sizes and calls the skb receive
- * helper with a shared skb.
+ * It checks skb, netlink header and msg sizes, and calls callback helper.
*/
static void cn_rx_skb(struct sk_buff *__skb)
{
struct nlmsghdr *nlh;
- u32 len;
int err;
struct sk_buff *skb;
skb = skb_get(__skb);
if (skb->len >= NLMSG_SPACE(0)) {
- nlh = (struct nlmsghdr *)skb->data;
+ nlh = nlmsg_hdr(skb);
if (nlh->nlmsg_len < sizeof(struct cn_msg) ||
skb->len < nlh->nlmsg_len ||
nlh->nlmsg_len > CONNECTOR_MAX_MSG_SIZE) {
kfree_skb(skb);
- goto out;
+ return;
}
- len = NLMSG_ALIGN(nlh->nlmsg_len);
- if (len > skb->len)
- len = skb->len;
-
- err = __cn_rx_skb(skb, nlh);
+ err = cn_call_callback(skb);
if (err < 0)
kfree_skb(skb);
}
-
-out:
- kfree_skb(__skb);
-}
-
-/*
- * Netlink socket input callback - dequeues the skbs and calls the
- * main netlink receiving function.
- */
-static void cn_input(struct sock *sk, int len)
-{
- struct sk_buff *skb;
-
- while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL)
- cn_rx_skb(skb);
}
/*
{
struct cn_ctl_entry *ent;
- down(¬ify_lock);
+ mutex_lock(¬ify_lock);
list_for_each_entry(ent, ¬ify_list, notify_entry) {
int i;
struct cn_notify_req *req;
req = (struct cn_notify_req *)ctl->data;
for (i = 0; i < ctl->idx_notify_num; ++i, ++req) {
- if (id->idx >= req->first &&
+ if (id->idx >= req->first &&
id->idx < req->first + req->range) {
idx_found = 1;
break;
}
for (i = 0; i < ctl->val_notify_num; ++i, ++req) {
- if (id->val >= req->first &&
+ if (id->val >= req->first &&
id->val < req->first + req->range) {
val_found = 1;
break;
cn_netlink_send(&m, ctl->group, GFP_KERNEL);
}
}
- up(¬ify_lock);
+ mutex_unlock(¬ify_lock);
}
/*
*
* May sleep.
*/
-int cn_add_callback(struct cb_id *id, char *name, void (*callback)(void *))
+int cn_add_callback(struct cb_id *id, char *name,
+ void (*callback)(struct cn_msg *, struct netlink_skb_parms *))
{
int err;
struct cn_dev *dev = &cdev;
- struct cn_callback *cb;
-
- cb = kzalloc(sizeof(*cb), GFP_KERNEL);
- if (!cb)
- return -ENOMEM;
- scnprintf(cb->name, sizeof(cb->name), "%s", name);
+ if (!cn_already_initialized)
+ return -EAGAIN;
- memcpy(&cb->id, id, sizeof(cb->id));
- cb->callback = callback;
-
- err = cn_queue_add_callback(dev->cbdev, cb);
- if (err) {
- kfree(cb);
+ err = cn_queue_add_callback(dev->cbdev, name, id, callback);
+ if (err)
return err;
- }
cn_notify(id, 0);
return 0;
}
+EXPORT_SYMBOL_GPL(cn_add_callback);
/*
* Callback remove routing - removes callback
cn_queue_del_callback(dev->cbdev, id);
cn_notify(id, 1);
}
+EXPORT_SYMBOL_GPL(cn_del_callback);
/*
* Checks two connector's control messages to be the same.
*
* Used for notification of a request's processing.
*/
-static void cn_callback(void *data)
+static void cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
{
- struct cn_msg *msg = data;
struct cn_ctl_msg *ctl;
struct cn_ctl_entry *ent;
u32 size;
if (ctl->group == 0) {
struct cn_ctl_entry *n;
- down(¬ify_lock);
+ mutex_lock(¬ify_lock);
list_for_each_entry_safe(ent, n, ¬ify_list, notify_entry) {
if (cn_ctl_msg_equals(ent->msg, ctl)) {
list_del(&ent->notify_entry);
kfree(ent);
}
}
- up(¬ify_lock);
+ mutex_unlock(¬ify_lock);
return;
}
memcpy(ent->msg, ctl, size - sizeof(*ent));
- down(¬ify_lock);
+ mutex_lock(¬ify_lock);
list_add(&ent->notify_entry, ¬ify_list);
- up(¬ify_lock);
+ mutex_unlock(¬ify_lock);
}
-static int __init cn_init(void)
+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;
int err;
- dev->input = cn_input;
+ dev->input = cn_rx_skb;
dev->id.idx = cn_idx;
dev->id.val = cn_val;
- dev->nls = netlink_kernel_create(NETLINK_CONNECTOR,
+ dev->nls = netlink_kernel_create(&init_net, NETLINK_CONNECTOR,
CN_NETLINK_USERS + 0xf,
- dev->input, THIS_MODULE);
+ dev->input, NULL, THIS_MODULE);
if (!dev->nls)
return -EIO;
dev->cbdev = cn_queue_alloc_dev("cqueue", dev->nls);
if (!dev->cbdev) {
- if (dev->nls->sk_socket)
- sock_release(dev->nls->sk_socket);
+ netlink_kernel_release(dev->nls);
return -EINVAL;
}
+ cn_already_initialized = 1;
+
err = cn_add_callback(&dev->id, "connector", &cn_callback);
if (err) {
+ cn_already_initialized = 0;
cn_queue_free_dev(dev->cbdev);
- if (dev->nls->sk_socket)
- sock_release(dev->nls->sk_socket);
+ netlink_kernel_release(dev->nls);
return -EINVAL;
}
- cn_already_initialized = 1;
+ proc_net_fops_create(&init_net, "connector", S_IRUGO, &cn_file_ops);
return 0;
}
-static void __exit cn_fini(void)
+static void __devexit cn_fini(void)
{
struct cn_dev *dev = &cdev;
cn_already_initialized = 0;
+ proc_net_remove(&init_net, "connector");
+
cn_del_callback(&dev->id);
cn_queue_free_dev(dev->cbdev);
- if (dev->nls->sk_socket)
- sock_release(dev->nls->sk_socket);
+ netlink_kernel_release(dev->nls);
}
-module_init(cn_init);
+subsys_initcall(cn_init);
module_exit(cn_fini);
-
-EXPORT_SYMBOL_GPL(cn_add_callback);
-EXPORT_SYMBOL_GPL(cn_del_callback);
-EXPORT_SYMBOL_GPL(cn_netlink_send);