net: ppp_generic - introduce net-namespace functionality v2
- Each namespace contains ppp channels and units separately
with appropriate locks
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ppp_generic.c b/drivers/net/ppp_generic.c
index 7b2728b..4405a76 100644
--- a/drivers/net/ppp_generic.c
+++ b/drivers/net/ppp_generic.c
@@ -49,6 +49,10 @@
#include <net/slhc_vj.h>
#include <asm/atomic.h>
+#include <linux/nsproxy.h>
+#include <net/net_namespace.h>
+#include <net/netns/generic.h>
+
#define PPP_VERSION "2.4.2"
/*
@@ -131,6 +135,7 @@
struct sock_filter *active_filter;/* filter for pkts to reset idle */
unsigned pass_len, active_len;
#endif /* CONFIG_PPP_FILTER */
+ struct net *ppp_net; /* the net we belong to */
};
/*
@@ -155,6 +160,7 @@
struct rw_semaphore chan_sem; /* protects `chan' during chan ioctl */
spinlock_t downl; /* protects `chan', file.xq dequeue */
struct ppp *ppp; /* ppp unit we're connected to */
+ struct net *chan_net; /* the net channel belongs to */
struct list_head clist; /* link in list of channels per unit */
rwlock_t upl; /* protects `ppp' */
#ifdef CONFIG_PPP_MULTILINK
@@ -173,26 +179,35 @@
* channel.downl.
*/
-/*
- * all_ppp_mutex protects the all_ppp_units mapping.
- * It also ensures that finding a ppp unit in the all_ppp_units map
- * and updating its file.refcnt field is atomic.
- */
-static DEFINE_MUTEX(all_ppp_mutex);
static atomic_t ppp_unit_count = ATOMIC_INIT(0);
-static DEFINE_IDR(ppp_units_idr);
-
-/*
- * all_channels_lock protects all_channels and last_channel_index,
- * and the atomicity of find a channel and updating its file.refcnt
- * field.
- */
-static DEFINE_SPINLOCK(all_channels_lock);
-static LIST_HEAD(all_channels);
-static LIST_HEAD(new_channels);
-static int last_channel_index;
static atomic_t channel_count = ATOMIC_INIT(0);
+/* per-net private data for this module */
+static unsigned int ppp_net_id;
+struct ppp_net {
+ /* units to ppp mapping */
+ struct idr units_idr;
+
+ /*
+ * all_ppp_mutex protects the units_idr mapping.
+ * It also ensures that finding a ppp unit in the units_idr
+ * map and updating its file.refcnt field is atomic.
+ */
+ struct mutex all_ppp_mutex;
+
+ /* channels */
+ struct list_head all_channels;
+ struct list_head new_channels;
+ int last_channel_index;
+
+ /*
+ * all_channels_lock protects all_channels and
+ * last_channel_index, and the atomicity of find
+ * a channel and updating its file.refcnt field.
+ */
+ spinlock_t all_channels_lock;
+};
+
/* Get the PPP protocol number from a skb */
#define PPP_PROTO(skb) (((skb)->data[0] << 8) + (skb)->data[1])
@@ -216,8 +231,8 @@
#define seq_after(a, b) ((s32)((a) - (b)) > 0)
/* Prototypes. */
-static int ppp_unattached_ioctl(struct ppp_file *pf, struct file *file,
- unsigned int cmd, unsigned long arg);
+static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf,
+ struct file *file, unsigned int cmd, unsigned long arg);
static void ppp_xmit_process(struct ppp *ppp);
static void ppp_send_frame(struct ppp *ppp, struct sk_buff *skb);
static void ppp_push(struct ppp *ppp);
@@ -240,12 +255,12 @@
static void ppp_ccp_closed(struct ppp *ppp);
static struct compressor *find_compressor(int type);
static void ppp_get_stats(struct ppp *ppp, struct ppp_stats *st);
-static struct ppp *ppp_create_interface(int unit, int *retp);
+static struct ppp *ppp_create_interface(struct net *net, int unit, int *retp);
static void init_ppp_file(struct ppp_file *pf, int kind);
static void ppp_shutdown_interface(struct ppp *ppp);
static void ppp_destroy_interface(struct ppp *ppp);
-static struct ppp *ppp_find_unit(int unit);
-static struct channel *ppp_find_channel(int unit);
+static struct ppp *ppp_find_unit(struct ppp_net *pn, int unit);
+static struct channel *ppp_find_channel(struct ppp_net *pn, int unit);
static int ppp_connect_channel(struct channel *pch, int unit);
static int ppp_disconnect_channel(struct channel *pch);
static void ppp_destroy_channel(struct channel *pch);
@@ -256,6 +271,14 @@
static struct class *ppp_class;
+/* per net-namespace data */
+static inline struct ppp_net *ppp_pernet(struct net *net)
+{
+ BUG_ON(!net);
+
+ return net_generic(net, ppp_net_id);
+}
+
/* Translates a PPP protocol number to a NP index (NP == network protocol) */
static inline int proto_to_npindex(int proto)
{
@@ -544,7 +567,8 @@
int __user *p = argp;
if (!pf)
- return ppp_unattached_ioctl(pf, file, cmd, arg);
+ return ppp_unattached_ioctl(current->nsproxy->net_ns,
+ pf, file, cmd, arg);
if (cmd == PPPIOCDETACH) {
/*
@@ -763,12 +787,13 @@
return err;
}
-static int ppp_unattached_ioctl(struct ppp_file *pf, struct file *file,
- unsigned int cmd, unsigned long arg)
+static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf,
+ struct file *file, unsigned int cmd, unsigned long arg)
{
int unit, err = -EFAULT;
struct ppp *ppp;
struct channel *chan;
+ struct ppp_net *pn;
int __user *p = (int __user *)arg;
lock_kernel();
@@ -777,7 +802,7 @@
/* Create a new ppp unit */
if (get_user(unit, p))
break;
- ppp = ppp_create_interface(unit, &err);
+ ppp = ppp_create_interface(net, unit, &err);
if (!ppp)
break;
file->private_data = &ppp->file;
@@ -792,29 +817,31 @@
/* Attach to an existing ppp unit */
if (get_user(unit, p))
break;
- mutex_lock(&all_ppp_mutex);
err = -ENXIO;
- ppp = ppp_find_unit(unit);
+ pn = ppp_pernet(net);
+ mutex_lock(&pn->all_ppp_mutex);
+ ppp = ppp_find_unit(pn, unit);
if (ppp) {
atomic_inc(&ppp->file.refcnt);
file->private_data = &ppp->file;
err = 0;
}
- mutex_unlock(&all_ppp_mutex);
+ mutex_unlock(&pn->all_ppp_mutex);
break;
case PPPIOCATTCHAN:
if (get_user(unit, p))
break;
- spin_lock_bh(&all_channels_lock);
err = -ENXIO;
- chan = ppp_find_channel(unit);
+ pn = ppp_pernet(net);
+ spin_lock_bh(&pn->all_channels_lock);
+ chan = ppp_find_channel(pn, unit);
if (chan) {
atomic_inc(&chan->file.refcnt);
file->private_data = &chan->file;
err = 0;
}
- spin_unlock_bh(&all_channels_lock);
+ spin_unlock_bh(&pn->all_channels_lock);
break;
default:
@@ -834,6 +861,51 @@
.release = ppp_release
};
+static __net_init int ppp_init_net(struct net *net)
+{
+ struct ppp_net *pn;
+ int err;
+
+ pn = kzalloc(sizeof(*pn), GFP_KERNEL);
+ if (!pn)
+ return -ENOMEM;
+
+ idr_init(&pn->units_idr);
+ mutex_init(&pn->all_ppp_mutex);
+
+ INIT_LIST_HEAD(&pn->all_channels);
+ INIT_LIST_HEAD(&pn->new_channels);
+
+ spin_lock_init(&pn->all_channels_lock);
+
+ err = net_assign_generic(net, ppp_net_id, pn);
+ if (err) {
+ kfree(pn);
+ return err;
+ }
+
+ return 0;
+}
+
+static __net_exit void ppp_exit_net(struct net *net)
+{
+ struct ppp_net *pn;
+
+ pn = net_generic(net, ppp_net_id);
+ idr_destroy(&pn->units_idr);
+ /*
+ * if someone has cached our net then
+ * further net_generic call will return NULL
+ */
+ net_assign_generic(net, ppp_net_id, NULL);
+ kfree(pn);
+}
+
+static __net_initdata struct pernet_operations ppp_net_ops = {
+ .init = ppp_init_net,
+ .exit = ppp_exit_net,
+};
+
#define PPP_MAJOR 108
/* Called at boot time if ppp is compiled into the kernel,
@@ -843,25 +915,36 @@
int err;
printk(KERN_INFO "PPP generic driver version " PPP_VERSION "\n");
- err = register_chrdev(PPP_MAJOR, "ppp", &ppp_device_fops);
- if (!err) {
- ppp_class = class_create(THIS_MODULE, "ppp");
- if (IS_ERR(ppp_class)) {
- err = PTR_ERR(ppp_class);
- goto out_chrdev;
- }
- device_create(ppp_class, NULL, MKDEV(PPP_MAJOR, 0), NULL,
- "ppp");
+
+ err = register_pernet_gen_device(&ppp_net_id, &ppp_net_ops);
+ if (err) {
+ printk(KERN_ERR "failed to register PPP pernet device (%d)\n", err);
+ goto out;
}
-out:
- if (err)
+ err = register_chrdev(PPP_MAJOR, "ppp", &ppp_device_fops);
+ if (err) {
printk(KERN_ERR "failed to register PPP device (%d)\n", err);
- return err;
+ goto out_net;
+ }
+
+ ppp_class = class_create(THIS_MODULE, "ppp");
+ if (IS_ERR(ppp_class)) {
+ err = PTR_ERR(ppp_class);
+ goto out_chrdev;
+ }
+
+ /* not a big deal if we fail here :-) */
+ device_create(ppp_class, NULL, MKDEV(PPP_MAJOR, 0), NULL, "ppp");
+
+ return 0;
out_chrdev:
unregister_chrdev(PPP_MAJOR, "ppp");
- goto out;
+out_net:
+ unregister_pernet_gen_device(ppp_net_id, &ppp_net_ops);
+out:
+ return err;
}
/*
@@ -969,6 +1052,7 @@
dev->tx_queue_len = 3;
dev->type = ARPHRD_PPP;
dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
+ dev->features |= NETIF_F_NETNS_LOCAL;
}
/*
@@ -1986,19 +2070,27 @@
* Channel interface.
*/
-/*
- * Create a new, unattached ppp channel.
- */
-int
-ppp_register_channel(struct ppp_channel *chan)
+/* Create a new, unattached ppp channel. */
+int ppp_register_channel(struct ppp_channel *chan)
+{
+ return ppp_register_net_channel(current->nsproxy->net_ns, chan);
+}
+
+/* Create a new, unattached ppp channel for specified net. */
+int ppp_register_net_channel(struct net *net, struct ppp_channel *chan)
{
struct channel *pch;
+ struct ppp_net *pn;
pch = kzalloc(sizeof(struct channel), GFP_KERNEL);
if (!pch)
return -ENOMEM;
+
+ pn = ppp_pernet(net);
+
pch->ppp = NULL;
pch->chan = chan;
+ pch->chan_net = net;
chan->ppp = pch;
init_ppp_file(&pch->file, CHANNEL);
pch->file.hdrlen = chan->hdrlen;
@@ -2008,11 +2100,13 @@
init_rwsem(&pch->chan_sem);
spin_lock_init(&pch->downl);
rwlock_init(&pch->upl);
- spin_lock_bh(&all_channels_lock);
- pch->file.index = ++last_channel_index;
- list_add(&pch->list, &new_channels);
+
+ spin_lock_bh(&pn->all_channels_lock);
+ pch->file.index = ++pn->last_channel_index;
+ list_add(&pch->list, &pn->new_channels);
atomic_inc(&channel_count);
- spin_unlock_bh(&all_channels_lock);
+ spin_unlock_bh(&pn->all_channels_lock);
+
return 0;
}
@@ -2053,9 +2147,11 @@
ppp_unregister_channel(struct ppp_channel *chan)
{
struct channel *pch = chan->ppp;
+ struct ppp_net *pn;
if (!pch)
return; /* should never happen */
+
chan->ppp = NULL;
/*
@@ -2068,9 +2164,12 @@
spin_unlock_bh(&pch->downl);
up_write(&pch->chan_sem);
ppp_disconnect_channel(pch);
- spin_lock_bh(&all_channels_lock);
+
+ pn = ppp_pernet(pch->chan_net);
+ spin_lock_bh(&pn->all_channels_lock);
list_del(&pch->list);
- spin_unlock_bh(&all_channels_lock);
+ spin_unlock_bh(&pn->all_channels_lock);
+
pch->file.dead = 1;
wake_up_interruptible(&pch->file.rwait);
if (atomic_dec_and_test(&pch->file.refcnt))
@@ -2395,9 +2494,10 @@
* unit == -1 means allocate a new number.
*/
static struct ppp *
-ppp_create_interface(int unit, int *retp)
+ppp_create_interface(struct net *net, int unit, int *retp)
{
struct ppp *ppp;
+ struct ppp_net *pn;
struct net_device *dev = NULL;
int ret = -ENOMEM;
int i;
@@ -2406,6 +2506,8 @@
if (!dev)
goto out1;
+ pn = ppp_pernet(net);
+
ppp = netdev_priv(dev);
ppp->dev = dev;
ppp->mru = PPP_MRU;
@@ -2421,17 +2523,23 @@
skb_queue_head_init(&ppp->mrq);
#endif /* CONFIG_PPP_MULTILINK */
+ /*
+ * drum roll: don't forget to set
+ * the net device is belong to
+ */
+ dev_net_set(dev, net);
+
ret = -EEXIST;
- mutex_lock(&all_ppp_mutex);
+ mutex_lock(&pn->all_ppp_mutex);
if (unit < 0) {
- unit = unit_get(&ppp_units_idr, ppp);
+ unit = unit_get(&pn->units_idr, ppp);
if (unit < 0) {
*retp = unit;
goto out2;
}
} else {
- if (unit_find(&ppp_units_idr, unit))
+ if (unit_find(&pn->units_idr, unit))
goto out2; /* unit already exists */
/*
* if caller need a specified unit number
@@ -2442,7 +2550,7 @@
* fair but at least pppd will ask us to allocate
* new unit in this case so user is happy :)
*/
- unit = unit_set(&ppp_units_idr, ppp, unit);
+ unit = unit_set(&pn->units_idr, ppp, unit);
if (unit < 0)
goto out2;
}
@@ -2453,20 +2561,22 @@
ret = register_netdev(dev);
if (ret != 0) {
- unit_put(&ppp_units_idr, unit);
+ unit_put(&pn->units_idr, unit);
printk(KERN_ERR "PPP: couldn't register device %s (%d)\n",
dev->name, ret);
goto out2;
}
+ ppp->ppp_net = net;
+
atomic_inc(&ppp_unit_count);
- mutex_unlock(&all_ppp_mutex);
+ mutex_unlock(&pn->all_ppp_mutex);
*retp = 0;
return ppp;
out2:
- mutex_unlock(&all_ppp_mutex);
+ mutex_unlock(&pn->all_ppp_mutex);
free_netdev(dev);
out1:
*retp = ret;
@@ -2492,7 +2602,11 @@
*/
static void ppp_shutdown_interface(struct ppp *ppp)
{
- mutex_lock(&all_ppp_mutex);
+ struct ppp_net *pn;
+
+ pn = ppp_pernet(ppp->ppp_net);
+ mutex_lock(&pn->all_ppp_mutex);
+
/* This will call dev_close() for us. */
ppp_lock(ppp);
if (!ppp->closing) {
@@ -2502,11 +2616,12 @@
} else
ppp_unlock(ppp);
- unit_put(&ppp_units_idr, ppp->file.index);
+ unit_put(&pn->units_idr, ppp->file.index);
ppp->file.dead = 1;
ppp->owner = NULL;
wake_up_interruptible(&ppp->file.rwait);
- mutex_unlock(&all_ppp_mutex);
+
+ mutex_unlock(&pn->all_ppp_mutex);
}
/*
@@ -2554,9 +2669,9 @@
* The caller should have locked the all_ppp_mutex.
*/
static struct ppp *
-ppp_find_unit(int unit)
+ppp_find_unit(struct ppp_net *pn, int unit)
{
- return unit_find(&ppp_units_idr, unit);
+ return unit_find(&pn->units_idr, unit);
}
/*
@@ -2568,20 +2683,22 @@
* when we have a lot of channels in use.
*/
static struct channel *
-ppp_find_channel(int unit)
+ppp_find_channel(struct ppp_net *pn, int unit)
{
struct channel *pch;
- list_for_each_entry(pch, &new_channels, list) {
+ list_for_each_entry(pch, &pn->new_channels, list) {
if (pch->file.index == unit) {
- list_move(&pch->list, &all_channels);
+ list_move(&pch->list, &pn->all_channels);
return pch;
}
}
- list_for_each_entry(pch, &all_channels, list) {
+
+ list_for_each_entry(pch, &pn->all_channels, list) {
if (pch->file.index == unit)
return pch;
}
+
return NULL;
}
@@ -2592,11 +2709,14 @@
ppp_connect_channel(struct channel *pch, int unit)
{
struct ppp *ppp;
+ struct ppp_net *pn;
int ret = -ENXIO;
int hdrlen;
- mutex_lock(&all_ppp_mutex);
- ppp = ppp_find_unit(unit);
+ pn = ppp_pernet(pch->chan_net);
+
+ mutex_lock(&pn->all_ppp_mutex);
+ ppp = ppp_find_unit(pn, unit);
if (!ppp)
goto out;
write_lock_bh(&pch->upl);
@@ -2620,7 +2740,7 @@
outl:
write_unlock_bh(&pch->upl);
out:
- mutex_unlock(&all_ppp_mutex);
+ mutex_unlock(&pn->all_ppp_mutex);
return ret;
}
@@ -2677,7 +2797,7 @@
unregister_chrdev(PPP_MAJOR, "ppp");
device_destroy(ppp_class, MKDEV(PPP_MAJOR, 0));
class_destroy(ppp_class);
- idr_destroy(&ppp_units_idr);
+ unregister_pernet_gen_device(ppp_net_id, &ppp_net_ops);
}
/*
@@ -2743,6 +2863,7 @@
module_init(ppp_init);
module_exit(ppp_cleanup);
+EXPORT_SYMBOL(ppp_register_net_channel);
EXPORT_SYMBOL(ppp_register_channel);
EXPORT_SYMBOL(ppp_unregister_channel);
EXPORT_SYMBOL(ppp_channel_index);
diff --git a/include/linux/ppp_channel.h b/include/linux/ppp_channel.h
index a942892..9d64bdf 100644
--- a/include/linux/ppp_channel.h
+++ b/include/linux/ppp_channel.h
@@ -22,6 +22,7 @@
#include <linux/list.h>
#include <linux/skbuff.h>
#include <linux/poll.h>
+#include <net/net_namespace.h>
struct ppp_channel;
@@ -56,6 +57,9 @@
that we may have missed a packet. */
extern void ppp_input_error(struct ppp_channel *, int code);
+/* Attach a channel to a given PPP unit in specified net. */
+extern int ppp_register_net_channel(struct net *, struct ppp_channel *);
+
/* Attach a channel to a given PPP unit. */
extern int ppp_register_channel(struct ppp_channel *);