diff options
author | Eric W. Biederman <ebiederm@xmission.com> | 2011-06-15 10:21:48 -0700 |
---|---|---|
committer | Ziyan <jaraidaniel@gmail.com> | 2016-03-11 16:08:59 +0100 |
commit | e1405a6b24b7f9b84aee7aff6db09e5ca5c17cec (patch) | |
tree | 3480b8e0e625b0036af678e672a6491225e71ab6 /include/net | |
parent | a6bf34a158d63bc888bb8c89b86cbc95e5d986c3 (diff) | |
download | kernel_samsung_espresso10-e1405a6b24b7f9b84aee7aff6db09e5ca5c17cec.zip kernel_samsung_espresso10-e1405a6b24b7f9b84aee7aff6db09e5ca5c17cec.tar.gz kernel_samsung_espresso10-e1405a6b24b7f9b84aee7aff6db09e5ca5c17cec.tar.bz2 |
proc: Usable inode numbers for the namespace file descriptors.
Assign a unique proc inode to each namespace, and use that
inode number to ensure we only allocate at most one proc
inode for every namespace in proc.
A single proc inode per namespace allows userspace to test
to see if two processes are in the same namespace.
This has been a long requested feature and only blocked because
a naive implementation would put the id in a global space and
would ultimately require having a namespace for the names of
namespaces, making migration and certain virtualization tricks
impossible.
We still don't have per superblock inode numbers for proc, which
appears necessary for application unaware checkpoint/restart and
migrations (if the application is using namespace file descriptors)
but that is now allowd by the design if it becomes important.
I have preallocated the ipc and uts initial proc inode numbers so
their structures can be statically initialized.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
(cherry picked from commit 98f842e675f96ffac96e6c50315790912b2812be)
Diffstat (limited to 'include/net')
-rw-r--r-- | include/net/net_namespace.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index aef430d..850799f 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -52,6 +52,8 @@ struct net { struct list_head cleanup_list; /* namespaces on death row */ struct list_head exit_list; /* Use only net_mutex */ + unsigned int proc_inum; + struct proc_dir_entry *proc_net; struct proc_dir_entry *proc_net_stat; |