aboutsummaryrefslogtreecommitdiff
path: root/include/linux/proc_fs.h
diff options
context:
space:
mode:
authorEric W. Biederman <ebiederm@xmission.com>2011-06-15 10:21:48 -0700
committerEric W. Biederman <ebiederm@xmission.com>2012-11-20 04:19:49 -0800
commit98f842e675f96ffac96e6c50315790912b2812be (patch)
treeed4dee9a6e54e3443e9f3f1614c8a2fcf9b31e0a /include/linux/proc_fs.h
parentbf056bfa80596a5d14b26b17276a56a0dcb080e5 (diff)
downloadvexpress-lsk-98f842e675f96ffac96e6c50315790912b2812be.tar.gz
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>
Diffstat (limited to 'include/linux/proc_fs.h')
-rw-r--r--include/linux/proc_fs.h7
1 files changed, 6 insertions, 1 deletions
diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h
index bf1d000fbba..2e24018b7ce 100644
--- a/include/linux/proc_fs.h
+++ b/include/linux/proc_fs.h
@@ -28,7 +28,11 @@ struct mm_struct;
*/
enum {
- PROC_ROOT_INO = 1,
+ PROC_ROOT_INO = 1,
+ PROC_IPC_INIT_INO = 0xEFFFFFFFU,
+ PROC_UTS_INIT_INO = 0xEFFFFFFEU,
+ PROC_USER_INIT_INO = 0xEFFFFFFDU,
+ PROC_PID_INIT_INO = 0xEFFFFFFCU,
};
/*
@@ -263,6 +267,7 @@ struct proc_ns_operations {
void *(*get)(struct task_struct *task);
void (*put)(void *ns);
int (*install)(struct nsproxy *nsproxy, void *ns);
+ unsigned int (*inum)(void *ns);
};
extern const struct proc_ns_operations netns_operations;
extern const struct proc_ns_operations utsns_operations;