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original_kernel/include/net/net_namespace.h

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[NET]: Basic network namespace infrastructure. This is the basic infrastructure needed to support network namespaces. This infrastructure is: - Registration functions to support initializing per network namespace data when a network namespaces is created or destroyed. - struct net. The network namespace data structure. This structure will grow as variables are made per network namespace but this is the minimal starting point. - Functions to grab a reference to the network namespace. I provide both get/put functions that keep a network namespace from being freed. And hold/release functions serve as weak references and will warn if their count is not zero when the data structure is freed. Useful for dealing with more complicated data structures like the ipv4 route cache. - A list of all of the network namespaces so we can iterate over them. - A slab for the network namespace data structure allowing leaks to be spotted. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-12 17:50:50 +08:00
/*
* Operations on the network namespace
*/
#ifndef __NET_NET_NAMESPACE_H
#define __NET_NET_NAMESPACE_H
#include <asm/atomic.h>
#include <linux/workqueue.h>
#include <linux/list.h>
[NET]: Make /proc/net per network namespace This patch makes /proc/net per network namespace. It modifies the global variables proc_net and proc_net_stat to be per network namespace. The proc_net file helpers are modified to take a network namespace argument, and all of their callers are fixed to pass &init_net for that argument. This ensures that all of the /proc/net files are only visible and usable in the initial network namespace until the code behind them has been updated to be handle multiple network namespaces. Making /proc/net per namespace is necessary as at least some files in /proc/net depend upon the set of network devices which is per network namespace, and even more files in /proc/net have contents that are relevant to a single network namespace. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-12 18:01:34 +08:00
struct proc_dir_entry;
[NET]: Basic network namespace infrastructure. This is the basic infrastructure needed to support network namespaces. This infrastructure is: - Registration functions to support initializing per network namespace data when a network namespaces is created or destroyed. - struct net. The network namespace data structure. This structure will grow as variables are made per network namespace but this is the minimal starting point. - Functions to grab a reference to the network namespace. I provide both get/put functions that keep a network namespace from being freed. And hold/release functions serve as weak references and will warn if their count is not zero when the data structure is freed. Useful for dealing with more complicated data structures like the ipv4 route cache. - A list of all of the network namespaces so we can iterate over them. - A slab for the network namespace data structure allowing leaks to be spotted. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-12 17:50:50 +08:00
struct net {
atomic_t count; /* To decided when the network
* namespace should be freed.
*/
atomic_t use_count; /* To track references we
* destroy on demand
*/
struct list_head list; /* list of network namespaces */
struct work_struct work; /* work struct for freeing */
[NET]: Make /proc/net per network namespace This patch makes /proc/net per network namespace. It modifies the global variables proc_net and proc_net_stat to be per network namespace. The proc_net file helpers are modified to take a network namespace argument, and all of their callers are fixed to pass &init_net for that argument. This ensures that all of the /proc/net files are only visible and usable in the initial network namespace until the code behind them has been updated to be handle multiple network namespaces. Making /proc/net per namespace is necessary as at least some files in /proc/net depend upon the set of network devices which is per network namespace, and even more files in /proc/net have contents that are relevant to a single network namespace. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-12 18:01:34 +08:00
struct proc_dir_entry *proc_net;
struct proc_dir_entry *proc_net_stat;
struct proc_dir_entry *proc_net_root;
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-18 02:56:21 +08:00
struct list_head dev_base_head;
struct hlist_head *dev_name_head;
struct hlist_head *dev_index_head;
[NET]: Basic network namespace infrastructure. This is the basic infrastructure needed to support network namespaces. This infrastructure is: - Registration functions to support initializing per network namespace data when a network namespaces is created or destroyed. - struct net. The network namespace data structure. This structure will grow as variables are made per network namespace but this is the minimal starting point. - Functions to grab a reference to the network namespace. I provide both get/put functions that keep a network namespace from being freed. And hold/release functions serve as weak references and will warn if their count is not zero when the data structure is freed. Useful for dealing with more complicated data structures like the ipv4 route cache. - A list of all of the network namespaces so we can iterate over them. - A slab for the network namespace data structure allowing leaks to be spotted. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-12 17:50:50 +08:00
};
[NETNS]: Fix allnoconfig compilation error. When CONFIG_NET=no, init_net is unresolved because net_namespace.c is not compiled and the include pull init_net definition. This problem was very similar with the ipc namespace where the kernel can be compiled with SYSV ipc out. This patch fix that defining a macro which simply remove init_net initialization from nsproxy namespace aggregator. Compiled and booted on qemu-i386 with CONFIG_NET=no and CONFIG_NET=yes. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-13 15:16:29 +08:00
#ifdef CONFIG_NET
/* Init's network namespace */
[NET]: Basic network namespace infrastructure. This is the basic infrastructure needed to support network namespaces. This infrastructure is: - Registration functions to support initializing per network namespace data when a network namespaces is created or destroyed. - struct net. The network namespace data structure. This structure will grow as variables are made per network namespace but this is the minimal starting point. - Functions to grab a reference to the network namespace. I provide both get/put functions that keep a network namespace from being freed. And hold/release functions serve as weak references and will warn if their count is not zero when the data structure is freed. Useful for dealing with more complicated data structures like the ipv4 route cache. - A list of all of the network namespaces so we can iterate over them. - A slab for the network namespace data structure allowing leaks to be spotted. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-12 17:50:50 +08:00
extern struct net init_net;
[NETNS]: Fix allnoconfig compilation error. When CONFIG_NET=no, init_net is unresolved because net_namespace.c is not compiled and the include pull init_net definition. This problem was very similar with the ipc namespace where the kernel can be compiled with SYSV ipc out. This patch fix that defining a macro which simply remove init_net initialization from nsproxy namespace aggregator. Compiled and booted on qemu-i386 with CONFIG_NET=no and CONFIG_NET=yes. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-13 15:16:29 +08:00
#define INIT_NET_NS(net_ns) .net_ns = &init_net,
#else
#define INIT_NET_NS(net_ns)
#endif
[NET]: Basic network namespace infrastructure. This is the basic infrastructure needed to support network namespaces. This infrastructure is: - Registration functions to support initializing per network namespace data when a network namespaces is created or destroyed. - struct net. The network namespace data structure. This structure will grow as variables are made per network namespace but this is the minimal starting point. - Functions to grab a reference to the network namespace. I provide both get/put functions that keep a network namespace from being freed. And hold/release functions serve as weak references and will warn if their count is not zero when the data structure is freed. Useful for dealing with more complicated data structures like the ipv4 route cache. - A list of all of the network namespaces so we can iterate over them. - A slab for the network namespace data structure allowing leaks to be spotted. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-12 17:50:50 +08:00
extern struct list_head net_namespace_list;
extern void __put_net(struct net *net);
static inline struct net *get_net(struct net *net)
{
atomic_inc(&net->count);
return net;
}
[NET]: Fix race when opening a proc file while a network namespace is exiting. The problem: proc_net files remember which network namespace the are against but do not remember hold a reference count (as that would pin the network namespace). So we currently have a small window where the reference count on a network namespace may be incremented when opening a /proc file when it has already gone to zero. To fix this introduce maybe_get_net and get_proc_net. maybe_get_net increments the network namespace reference count only if it is greater then zero, ensuring we don't increment a reference count after it has gone to zero. get_proc_net handles all of the magic to go from a proc inode to the network namespace instance and call maybe_get_net on it. PROC_NET the old accessor is removed so that we don't get confused and use the wrong helper function. Then I fix up the callers to use get_proc_net and handle the case case where get_proc_net returns NULL. In that case I return -ENXIO because effectively the network namespace has already gone away so the files we are trying to access don't exist anymore. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-13 15:18:57 +08:00
static inline struct net *maybe_get_net(struct net *net)
{
/* Used when we know struct net exists but we
* aren't guaranteed a previous reference count
* exists. If the reference count is zero this
* function fails and returns NULL.
*/
if (!atomic_inc_not_zero(&net->count))
net = NULL;
return net;
}
[NET]: Basic network namespace infrastructure. This is the basic infrastructure needed to support network namespaces. This infrastructure is: - Registration functions to support initializing per network namespace data when a network namespaces is created or destroyed. - struct net. The network namespace data structure. This structure will grow as variables are made per network namespace but this is the minimal starting point. - Functions to grab a reference to the network namespace. I provide both get/put functions that keep a network namespace from being freed. And hold/release functions serve as weak references and will warn if their count is not zero when the data structure is freed. Useful for dealing with more complicated data structures like the ipv4 route cache. - A list of all of the network namespaces so we can iterate over them. - A slab for the network namespace data structure allowing leaks to be spotted. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-12 17:50:50 +08:00
static inline void put_net(struct net *net)
{
if (atomic_dec_and_test(&net->count))
__put_net(net);
}
static inline struct net *hold_net(struct net *net)
{
atomic_inc(&net->use_count);
return net;
}
static inline void release_net(struct net *net)
{
atomic_dec(&net->use_count);
}
extern void net_lock(void);
extern void net_unlock(void);
#define for_each_net(VAR) \
list_for_each_entry(VAR, &net_namespace_list, list)
struct pernet_operations {
struct list_head list;
int (*init)(struct net *net);
void (*exit)(struct net *net);
};
extern int register_pernet_subsys(struct pernet_operations *);
extern void unregister_pernet_subsys(struct pernet_operations *);
extern int register_pernet_device(struct pernet_operations *);
extern void unregister_pernet_device(struct pernet_operations *);
#endif /* __NET_NET_NAMESPACE_H */