Re: [PATCH 3/5] net: pppol2tp - introduce net-namespace functionality

From: James Chapman
Date: Tue Jan 20 2009 - 17:04:18 EST

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In reply to: Cyrill Gorcunov: "[PATCH 3/5] net: pppol2tp - introduce net-namespace functionality"
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Cyrill Gorcunov wrote:
> - Each tunnel and appropriate lock are inside own namespace now.
> - pppox code allows to create per-namespace sockets for
> both PX_PROTO_OE and PX_PROTO_OL2TP protocols. Actually since
> now pppox_create support net-namespaces new PPPo... protocols
> (if they ever will be) should support net-namespace too otherwise
> explicit check for &init_net would be needed.
>
> CC: James Chapman <jchapman@xxxxxxxxxxx>
> Signed-off-by: Cyrill Gorcunov <gorcunov@xxxxxxxxxx>

Changes look fine for pppol2tp. I tested again in my L2TP setup.

Signed-off-by: James Chapman <jchapman@xxxxxxxxxxx>

> ---
> drivers/net/pppol2tp.c | 160 +++++++++++++++++++++++++++++++++++--------------
> drivers/net/pppox.c | 4 -
> 2 files changed, 117 insertions(+), 47 deletions(-)
>
> Index: linux-2.6.git/drivers/net/pppol2tp.c
> ===================================================================
> --- linux-2.6.git.orig/drivers/net/pppol2tp.c
> +++ linux-2.6.git/drivers/net/pppol2tp.c
> @@ -90,7 +90,9 @@
> #include <linux/hash.h>
> #include <linux/sort.h>
> #include <linux/proc_fs.h>
> +#include <linux/nsproxy.h>
> #include <net/net_namespace.h>
> +#include <net/netns/generic.h>
> #include <net/dst.h>
> #include <net/ip.h>
> #include <net/udp.h>
> @@ -204,6 +206,7 @@ struct pppol2tp_tunnel
> struct sock *sock; /* Parent socket */
> struct list_head list; /* Keep a list of all open
> * prepared sockets */
> + struct net *pppol2tp_net; /* the net we belong to */
>
> atomic_t ref_count;
> };
> @@ -227,8 +230,20 @@ static atomic_t pppol2tp_tunnel_count;
> static atomic_t pppol2tp_session_count;
> static struct ppp_channel_ops pppol2tp_chan_ops = { pppol2tp_xmit , NULL };
> static struct proto_ops pppol2tp_ops;
> -static LIST_HEAD(pppol2tp_tunnel_list);
> -static DEFINE_RWLOCK(pppol2tp_tunnel_list_lock);
> +
> +/* per-net private data for this module */
> +static unsigned int pppol2tp_net_id;
> +struct pppol2tp_net {
> + struct list_head pppol2tp_tunnel_list;
> + rwlock_t pppol2tp_tunnel_list_lock;
> +};
> +
> +static inline struct pppol2tp_net *pppol2tp_pernet(struct net *net)
> +{
> + BUG_ON(!net);
> +
> + return net_generic(net, pppol2tp_net_id);
> +}
>
> /* Helpers to obtain tunnel/session contexts from sockets.
> */
> @@ -321,18 +336,19 @@ pppol2tp_session_find(struct pppol2tp_tu
>
> /* Lookup a tunnel by id
> */
> -static struct pppol2tp_tunnel *pppol2tp_tunnel_find(u16 tunnel_id)
> +static struct pppol2tp_tunnel *pppol2tp_tunnel_find(struct net *net, u16 tunnel_id)
> {
> - struct pppol2tp_tunnel *tunnel = NULL;
> + struct pppol2tp_tunnel *tunnel;
> + struct pppol2tp_net *pn = pppol2tp_pernet(net);
>
> - read_lock_bh(&pppol2tp_tunnel_list_lock);
> - list_for_each_entry(tunnel, &pppol2tp_tunnel_list, list) {
> + read_lock_bh(&pn->pppol2tp_tunnel_list_lock);
> + list_for_each_entry(tunnel, &pn->pppol2tp_tunnel_list, list) {
> if (tunnel->stats.tunnel_id == tunnel_id) {
> - read_unlock_bh(&pppol2tp_tunnel_list_lock);
> + read_unlock_bh(&pn->pppol2tp_tunnel_list_lock);
> return tunnel;
> }
> }
> - read_unlock_bh(&pppol2tp_tunnel_list_lock);
> + read_unlock_bh(&pn->pppol2tp_tunnel_list_lock);
>
> return NULL;
> }
> @@ -1287,10 +1303,12 @@ again:
> */
> static void pppol2tp_tunnel_free(struct pppol2tp_tunnel *tunnel)
> {
> + struct pppol2tp_net *pn = pppol2tp_pernet(tunnel->pppol2tp_net);
> +
> /* Remove from socket list */
> - write_lock_bh(&pppol2tp_tunnel_list_lock);
> + write_lock_bh(&pn->pppol2tp_tunnel_list_lock);
> list_del_init(&tunnel->list);
> - write_unlock_bh(&pppol2tp_tunnel_list_lock);
> + write_unlock_bh(&pn->pppol2tp_tunnel_list_lock);
>
> atomic_dec(&pppol2tp_tunnel_count);
> kfree(tunnel);
> @@ -1444,13 +1462,14 @@ error:
> /* Internal function to prepare a tunnel (UDP) socket to have PPPoX
> * sockets attached to it.
> */
> -static struct sock *pppol2tp_prepare_tunnel_socket(int fd, u16 tunnel_id,
> - int *error)
> +static struct sock *pppol2tp_prepare_tunnel_socket(struct net *net,
> + int fd, u16 tunnel_id, int *error)
> {
> int err;
> struct socket *sock = NULL;
> struct sock *sk;
> struct pppol2tp_tunnel *tunnel;
> + struct pppol2tp_net *pn;
> struct sock *ret = NULL;
>
> /* Get the tunnel UDP socket from the fd, which was opened by
> @@ -1524,11 +1543,15 @@ static struct sock *pppol2tp_prepare_tun
> /* Misc init */
> rwlock_init(&tunnel->hlist_lock);
>
> + /* The net we belong to */
> + tunnel->pppol2tp_net = net;
> + pn = pppol2tp_pernet(net);
> +
> /* Add tunnel to our list */
> INIT_LIST_HEAD(&tunnel->list);
> - write_lock_bh(&pppol2tp_tunnel_list_lock);
> - list_add(&tunnel->list, &pppol2tp_tunnel_list);
> - write_unlock_bh(&pppol2tp_tunnel_list_lock);
> + write_lock_bh(&pn->pppol2tp_tunnel_list_lock);
> + list_add(&tunnel->list, &pn->pppol2tp_tunnel_list);
> + write_unlock_bh(&pn->pppol2tp_tunnel_list_lock);
> atomic_inc(&pppol2tp_tunnel_count);
>
> /* Bump the reference count. The tunnel context is deleted
> @@ -1629,7 +1652,8 @@ static int pppol2tp_connect(struct socke
> * tunnel id.
> */
> if ((sp->pppol2tp.s_session == 0) && (sp->pppol2tp.d_session == 0)) {
> - tunnel_sock = pppol2tp_prepare_tunnel_socket(sp->pppol2tp.fd,
> + tunnel_sock = pppol2tp_prepare_tunnel_socket(sock_net(sk),
> + sp->pppol2tp.fd,
> sp->pppol2tp.s_tunnel,
> &error);
> if (tunnel_sock == NULL)
> @@ -1637,7 +1661,7 @@ static int pppol2tp_connect(struct socke
>
> tunnel = tunnel_sock->sk_user_data;
> } else {
> - tunnel = pppol2tp_tunnel_find(sp->pppol2tp.s_tunnel);
> + tunnel = pppol2tp_tunnel_find(sock_net(sk), sp->pppol2tp.s_tunnel);
>
> /* Error if we can't find the tunnel */
> error = -ENOENT;
> @@ -2347,8 +2371,9 @@ end:
> #include <linux/seq_file.h>
>
> struct pppol2tp_seq_data {
> - struct pppol2tp_tunnel *tunnel; /* current tunnel */
> - struct pppol2tp_session *session; /* NULL means get first session in tunnel */
> + struct net *seq_net; /* net of inode */
> + struct pppol2tp_tunnel *tunnel; /* current tunnel */
> + struct pppol2tp_session *session; /* NULL means get first session in tunnel */
> };
>
> static struct pppol2tp_session *next_session(struct pppol2tp_tunnel *tunnel, struct pppol2tp_session *curr)
> @@ -2384,17 +2409,18 @@ out:
> return session;
> }
>
> -static struct pppol2tp_tunnel *next_tunnel(struct pppol2tp_tunnel *curr)
> +static struct pppol2tp_tunnel *next_tunnel(struct pppol2tp_net *pn,
> + struct pppol2tp_tunnel *curr)
> {
> struct pppol2tp_tunnel *tunnel = NULL;
>
> - read_lock_bh(&pppol2tp_tunnel_list_lock);
> - if (list_is_last(&curr->list, &pppol2tp_tunnel_list)) {
> + read_lock_bh(&pn->pppol2tp_tunnel_list_lock);
> + if (list_is_last(&curr->list, &pn->pppol2tp_tunnel_list)) {
> goto out;
> }
> tunnel = list_entry(curr->list.next, struct pppol2tp_tunnel, list);
> out:
> - read_unlock_bh(&pppol2tp_tunnel_list_lock);
> + read_unlock_bh(&pn->pppol2tp_tunnel_list_lock);
>
> return tunnel;
> }
> @@ -2402,6 +2428,7 @@ out:
> static void *pppol2tp_seq_start(struct seq_file *m, loff_t *offs)
> {
> struct pppol2tp_seq_data *pd = SEQ_START_TOKEN;
> + struct pppol2tp_net *pn;
> loff_t pos = *offs;
>
> if (!pos)
> @@ -2409,14 +2436,15 @@ static void *pppol2tp_seq_start(struct s
>
> BUG_ON(m->private == NULL);
> pd = m->private;
> + pn = pppol2tp_pernet(pd->seq_net);
>
> if (pd->tunnel == NULL) {
> - if (!list_empty(&pppol2tp_tunnel_list))
> - pd->tunnel = list_entry(pppol2tp_tunnel_list.next, struct pppol2tp_tunnel, list);
> + if (!list_empty(&pn->pppol2tp_tunnel_list))
> + pd->tunnel = list_entry(pn->pppol2tp_tunnel_list.next, struct pppol2tp_tunnel, list);
> } else {
> pd->session = next_session(pd->tunnel, pd->session);
> if (pd->session == NULL) {
> - pd->tunnel = next_tunnel(pd->tunnel);
> + pd->tunnel = next_tunnel(pn, pd->tunnel);
> }
> }
>
> @@ -2532,6 +2560,7 @@ static int pppol2tp_proc_open(struct ino
> {
> struct seq_file *m;
> struct pppol2tp_seq_data *pd;
> + struct net *net;
> int ret = 0;
>
> ret = seq_open(file, &pppol2tp_seq_ops);
> @@ -2542,12 +2571,15 @@ static int pppol2tp_proc_open(struct ino
>
> /* Allocate and fill our proc_data for access later */
> ret = -ENOMEM;
> - m->private = kzalloc(sizeof(struct pppol2tp_seq_data), GFP_KERNEL);
> + m->private = kzalloc(sizeof(*pd), GFP_KERNEL);
> if (m->private == NULL)
> goto out;
>
> pd = m->private;
> - ret = 0;
> + net = maybe_get_net(PDE_NET(PDE(inode)));
> + BUG_ON(!net);
> + pd->seq_net = net;
> + return 0;
>
> out:
> return ret;
> @@ -2558,6 +2590,9 @@ out:
> static int pppol2tp_proc_release(struct inode *inode, struct file *file)
> {
> struct seq_file *m = (struct seq_file *)file->private_data;
> + struct pppol2tp_seq_data *pd = m->private;
> +
> + put_net(pd->seq_net);
>
> kfree(m->private);
> m->private = NULL;
> @@ -2573,8 +2608,6 @@ static struct file_operations pppol2tp_p
> .release = pppol2tp_proc_release,
> };
>
> -static struct proc_dir_entry *pppol2tp_proc;
> -
> #endif /* CONFIG_PROC_FS */
>
> /*****************************************************************************
> @@ -2606,6 +2639,57 @@ static struct pppox_proto pppol2tp_proto
> .ioctl = pppol2tp_ioctl
> };
>
> +static __net_init int pppol2tp_init_net(struct net *net)
> +{
> + struct pppol2tp_net *pn;
> + struct proc_dir_entry *pde;
> + int err;
> +
> + pn = kzalloc(sizeof(*pn), GFP_KERNEL);
> + if (!pn)
> + return -ENOMEM;
> +
> + INIT_LIST_HEAD(&pn->pppol2tp_tunnel_list);
> + rwlock_init(&pn->pppol2tp_tunnel_list_lock);
> +
> + err = net_assign_generic(net, pppol2tp_net_id, pn);
> + if (err)
> + goto out;
> +
> + pde = proc_net_fops_create(net, "pppol2tp", S_IRUGO, &pppol2tp_proc_fops);
> +#ifdef CONFIG_PROC_FS
> + if (!pde) {
> + err = -ENOMEM;
> + goto out;
> + }
> +#endif
> +
> + return 0;
> +
> +out:
> + kfree(pn);
> + return err;
> +}
> +
> +static __net_exit void pppol2tp_exit_net(struct net *net)
> +{
> + struct pppoe_net *pn;
> +
> + proc_net_remove(net, "pppol2tp");
> + pn = net_generic(net, pppol2tp_net_id);
> + /*
> + * if someone has cached our net then
> + * further net_generic call will return NULL
> + */
> + net_assign_generic(net, pppol2tp_net_id, NULL);
> + kfree(pn);
> +}
> +
> +static __net_initdata struct pernet_operations pppol2tp_net_ops = {
> + .init = pppol2tp_init_net,
> + .exit = pppol2tp_exit_net,
> +};
> +
> static int __init pppol2tp_init(void)
> {
> int err;
> @@ -2617,23 +2701,17 @@ static int __init pppol2tp_init(void)
> if (err)
> goto out_unregister_pppol2tp_proto;
>
> -#ifdef CONFIG_PROC_FS
> - pppol2tp_proc = proc_net_fops_create(&init_net, "pppol2tp", 0,
> - &pppol2tp_proc_fops);
> - if (!pppol2tp_proc) {
> - err = -ENOMEM;
> + err = register_pernet_gen_device(&pppol2tp_net_id, &pppol2tp_net_ops);
> + if (err)
> goto out_unregister_pppox_proto;
> - }
> -#endif /* CONFIG_PROC_FS */
> +
> printk(KERN_INFO "PPPoL2TP kernel driver, %s\n",
> PPPOL2TP_DRV_VERSION);
>
> out:
> return err;
> -#ifdef CONFIG_PROC_FS
> out_unregister_pppox_proto:
> unregister_pppox_proto(PX_PROTO_OL2TP);
> -#endif
> out_unregister_pppol2tp_proto:
> proto_unregister(&pppol2tp_sk_proto);
> goto out;
> @@ -2642,10 +2720,6 @@ out_unregister_pppol2tp_proto:
> static void __exit pppol2tp_exit(void)
> {
> unregister_pppox_proto(PX_PROTO_OL2TP);
> -
> -#ifdef CONFIG_PROC_FS
> - remove_proc_entry("pppol2tp", init_net.proc_net);
> -#endif
> proto_unregister(&pppol2tp_sk_proto);
> }
>
> Index: linux-2.6.git/drivers/net/pppox.c
> ===================================================================
> --- linux-2.6.git.orig/drivers/net/pppox.c
> +++ linux-2.6.git/drivers/net/pppox.c
> @@ -111,10 +111,6 @@ static int pppox_create(struct net *net,
> if (protocol < 0 || protocol > PX_MAX_PROTO)
> goto out;
>
> - /* we support net-namespaces for PPPoE only (yet) */
> - if (protocol != PX_PROTO_OE && net != &init_net)
> - return -EAFNOSUPPORT;
> -
> rc = -EPROTONOSUPPORT;
> if (!pppox_protos[protocol])
> request_module("pppox-proto-%d", protocol);
>

--
James Chapman
Katalix Systems Ltd
http://www.katalix.com
Catalysts for your Embedded Linux software development

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Next message: Mingming Cao: "Re: [PATCH 09/11] ext3: Remove unnecessary quota functions"
Previous message: mike zheng: "How to check input device"
In reply to: Cyrill Gorcunov: "[PATCH 3/5] net: pppol2tp - introduce net-namespace functionality"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]