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| author | Pavel Emelyanov <xemul@openvz.org> | 2007-10-18 23:40:02 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-19 11:53:38 -0700 |
| commit | 8bf9725c29f2589237dd696d06a204230add0ba3 (patch) | |
| tree | abe1a29924a592808250121435dcd12789336e8a /include | |
| parent | 2e4a707269a409950c3f315010c20f9719c594e2 (diff) | |
| download | linux-8bf9725c29f2589237dd696d06a204230add0ba3.tar.gz linux-8bf9725c29f2589237dd696d06a204230add0ba3.tar.bz2 linux-8bf9725c29f2589237dd696d06a204230add0ba3.zip | |
pid namespaces: introduce MS_KERNMOUNT flag
This flag tells the .get_sb callback that this is a kern_mount() call so that
it can trust *data pointer to be valid in-kernel one. If this flag is passed
from the user process, it is cleared since the *data pointer is not a valid
kernel object.
Running a few steps forward - this will be needed for proc to create the
superblock and store a valid pid namespace on it during the namespace
creation. The reason, why the namespace cannot live without proc mount is
described in the appropriate patch.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/fs.h | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/include/linux/fs.h b/include/linux/fs.h index 3efff12049c6..1657e995f72c 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -123,6 +123,7 @@ extern int dir_notify_enable; #define MS_SLAVE (1<<19) /* change to slave */ #define MS_SHARED (1<<20) /* change to shared */ #define MS_RELATIME (1<<21) /* Update atime relative to mtime/ctime. */ +#define MS_KERNMOUNT (1<<22) /* this is a kern_mount call */ #define MS_ACTIVE (1<<30) #define MS_NOUSER (1<<31) @@ -1459,7 +1460,8 @@ void unnamed_dev_init(void); extern int register_filesystem(struct file_system_type *); extern int unregister_filesystem(struct file_system_type *); -extern struct vfsmount *kern_mount(struct file_system_type *); +extern struct vfsmount *kern_mount_data(struct file_system_type *, void *data); +#define kern_mount(type) kern_mount_data(type, NULL) extern int may_umount_tree(struct vfsmount *); extern int may_umount(struct vfsmount *); extern void umount_tree(struct vfsmount *, int, struct list_head *); |