mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-18 18:23:53 +08:00
6164281ab7
Currently on 64-bit arch the user_namespace is 2096 and when being kmalloc-ed it resides on a 4k slab wasting 2003 bytes. If we allocate a separate cache for it and reduce the hash size from 128 to 64 chains the packaging becomes *much* better - the struct is 1072 bytes and the hole between is 98 bytes. [akpm@linux-foundation.org: s/__initcall/module_init/] Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Acked-by: Serge E. Hallyn <serge@hallyn.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
72 lines
1.5 KiB
C
72 lines
1.5 KiB
C
#ifndef _LINUX_USER_NAMESPACE_H
|
|
#define _LINUX_USER_NAMESPACE_H
|
|
|
|
#include <linux/kref.h>
|
|
#include <linux/nsproxy.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/err.h>
|
|
|
|
#define UIDHASH_BITS (CONFIG_BASE_SMALL ? 3 : 7)
|
|
#define UIDHASH_SZ (1 << UIDHASH_BITS)
|
|
|
|
struct user_namespace {
|
|
struct kref kref;
|
|
struct hlist_head uidhash_table[UIDHASH_SZ];
|
|
struct user_struct *creator;
|
|
struct work_struct destroyer;
|
|
};
|
|
|
|
extern struct user_namespace init_user_ns;
|
|
|
|
#ifdef CONFIG_USER_NS
|
|
|
|
static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
|
|
{
|
|
if (ns)
|
|
kref_get(&ns->kref);
|
|
return ns;
|
|
}
|
|
|
|
extern int create_user_ns(struct cred *new);
|
|
extern void free_user_ns(struct kref *kref);
|
|
|
|
static inline void put_user_ns(struct user_namespace *ns)
|
|
{
|
|
if (ns)
|
|
kref_put(&ns->kref, free_user_ns);
|
|
}
|
|
|
|
uid_t user_ns_map_uid(struct user_namespace *to, const struct cred *cred, uid_t uid);
|
|
gid_t user_ns_map_gid(struct user_namespace *to, const struct cred *cred, gid_t gid);
|
|
|
|
#else
|
|
|
|
static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
|
|
{
|
|
return &init_user_ns;
|
|
}
|
|
|
|
static inline int create_user_ns(struct cred *new)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
static inline void put_user_ns(struct user_namespace *ns)
|
|
{
|
|
}
|
|
|
|
static inline uid_t user_ns_map_uid(struct user_namespace *to,
|
|
const struct cred *cred, uid_t uid)
|
|
{
|
|
return uid;
|
|
}
|
|
static inline gid_t user_ns_map_gid(struct user_namespace *to,
|
|
const struct cred *cred, gid_t gid)
|
|
{
|
|
return gid;
|
|
}
|
|
|
|
#endif
|
|
|
|
#endif /* _LINUX_USER_H */
|