GitHub-Mirror/linux-bl808
2
0
Fork 0
mirror of https://github.com/Fishwaldo/linux-bl808.git synced 2025-06-17 20:25:19 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

Cache user_ns in struct cred

Browse source 
If !CONFIG_USERNS, have current_user_ns() defined to (&init_user_ns).

Get rid of _current_user_ns.  This requires nsown_capable() to be
defined in capability.c rather than as static inline in capability.h,
so do that.

Request_key needs init_user_ns defined at current_user_ns if
!CONFIG_USERNS, so forward-declare that in cred.h if !CONFIG_USERNS
at current_user_ns() define.

Compile-tested with and without CONFIG_USERNS.

Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com>
[ This makes a huge performance difference for acl_permission_check(),
  up to 30%.  And that is one of the hottest kernel functions for loads
  that are pathname-lookup heavy.  ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Serge E. Hallyn 2011-05-13 04:27:54 +01:00 • committed by Linus Torvalds
parent 381e7863d9
commit 47a150edc2
4 changed files with 27 additions and 20 deletions
Download patch file Download diff file Expand all files Collapse all files

13
include/linux/capability.h
View file

@ -546,18 +546,7 @@ extern bool has_capability_noaudit(struct task_struct *t, int cap);
extern bool capable(int cap);
extern bool ns_capable(struct user_namespace *ns, int cap);
extern bool task_ns_capable(struct task_struct *t, int cap);
/**
* nsown_capable - Check superior capability to one's own user_ns
* @cap: The capability in question
*
* Return true if the current task has the given superior capability
* targeted at its own user namespace.
*/
static inline bool nsown_capable(int cap)
{
return ns_capable(current_user_ns(), cap);
}
extern bool nsown_capable(int cap);
/* audit system wants to get cap info from files as well */
extern int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps);