mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-12 13:55:32 +00:00
![Christian Brauner](/assets/img/avatar_default.png)
The low-level mapping helpers were so far crammed into fs.h. They are out of place there. The fs.h header should just contain the higher-level mapping helpers that interact directly with vfs objects such as struct super_block or struct inode and not the bare mapping helpers. Similarly, only vfs and specific fs code shall interact with low-level mapping helpers. And so they won't be made accessible automatically through regular {g,u}id helpers. Link: https://lore.kernel.org/r/20211123114227.3124056-3-brauner@kernel.org (v1) Link: https://lore.kernel.org/r/20211130121032.3753852-3-brauner@kernel.org (v2) Link: https://lore.kernel.org/r/20211203111707.3901969-3-brauner@kernel.org Cc: Seth Forshee <sforshee@digitalocean.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> CC: linux-fsdevel@vger.kernel.org Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Seth Forshee <sforshee@digitalocean.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
101 lines
3 KiB
C
101 lines
3 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _LINUX_MNT_IDMAPPING_H
|
|
#define _LINUX_MNT_IDMAPPING_H
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/uidgid.h>
|
|
|
|
struct user_namespace;
|
|
extern struct user_namespace init_user_ns;
|
|
|
|
/**
|
|
* kuid_into_mnt - map a kuid down into a mnt_userns
|
|
* @mnt_userns: user namespace of the relevant mount
|
|
* @kuid: kuid to be mapped
|
|
*
|
|
* Return: @kuid mapped according to @mnt_userns.
|
|
* If @kuid has no mapping INVALID_UID is returned.
|
|
*/
|
|
static inline kuid_t kuid_into_mnt(struct user_namespace *mnt_userns,
|
|
kuid_t kuid)
|
|
{
|
|
return make_kuid(mnt_userns, __kuid_val(kuid));
|
|
}
|
|
|
|
/**
|
|
* kgid_into_mnt - map a kgid down into a mnt_userns
|
|
* @mnt_userns: user namespace of the relevant mount
|
|
* @kgid: kgid to be mapped
|
|
*
|
|
* Return: @kgid mapped according to @mnt_userns.
|
|
* If @kgid has no mapping INVALID_GID is returned.
|
|
*/
|
|
static inline kgid_t kgid_into_mnt(struct user_namespace *mnt_userns,
|
|
kgid_t kgid)
|
|
{
|
|
return make_kgid(mnt_userns, __kgid_val(kgid));
|
|
}
|
|
|
|
/**
|
|
* kuid_from_mnt - map a kuid up into a mnt_userns
|
|
* @mnt_userns: user namespace of the relevant mount
|
|
* @kuid: kuid to be mapped
|
|
*
|
|
* Return: @kuid mapped up according to @mnt_userns.
|
|
* If @kuid has no mapping INVALID_UID is returned.
|
|
*/
|
|
static inline kuid_t kuid_from_mnt(struct user_namespace *mnt_userns,
|
|
kuid_t kuid)
|
|
{
|
|
return KUIDT_INIT(from_kuid(mnt_userns, kuid));
|
|
}
|
|
|
|
/**
|
|
* kgid_from_mnt - map a kgid up into a mnt_userns
|
|
* @mnt_userns: user namespace of the relevant mount
|
|
* @kgid: kgid to be mapped
|
|
*
|
|
* Return: @kgid mapped up according to @mnt_userns.
|
|
* If @kgid has no mapping INVALID_GID is returned.
|
|
*/
|
|
static inline kgid_t kgid_from_mnt(struct user_namespace *mnt_userns,
|
|
kgid_t kgid)
|
|
{
|
|
return KGIDT_INIT(from_kgid(mnt_userns, kgid));
|
|
}
|
|
|
|
/**
|
|
* mapped_fsuid - return caller's fsuid mapped up into a mnt_userns
|
|
* @mnt_userns: user namespace of the relevant mount
|
|
*
|
|
* Use this helper to initialize a new vfs or filesystem object based on
|
|
* the caller's fsuid. A common example is initializing the i_uid field of
|
|
* a newly allocated inode triggered by a creation event such as mkdir or
|
|
* O_CREAT. Other examples include the allocation of quotas for a specific
|
|
* user.
|
|
*
|
|
* Return: the caller's current fsuid mapped up according to @mnt_userns.
|
|
*/
|
|
static inline kuid_t mapped_fsuid(struct user_namespace *mnt_userns)
|
|
{
|
|
return kuid_from_mnt(mnt_userns, current_fsuid());
|
|
}
|
|
|
|
/**
|
|
* mapped_fsgid - return caller's fsgid mapped up into a mnt_userns
|
|
* @mnt_userns: user namespace of the relevant mount
|
|
*
|
|
* Use this helper to initialize a new vfs or filesystem object based on
|
|
* the caller's fsgid. A common example is initializing the i_gid field of
|
|
* a newly allocated inode triggered by a creation event such as mkdir or
|
|
* O_CREAT. Other examples include the allocation of quotas for a specific
|
|
* user.
|
|
*
|
|
* Return: the caller's current fsgid mapped up according to @mnt_userns.
|
|
*/
|
|
static inline kgid_t mapped_fsgid(struct user_namespace *mnt_userns)
|
|
{
|
|
return kgid_from_mnt(mnt_userns, current_fsgid());
|
|
}
|
|
|
|
#endif /* _LINUX_MNT_IDMAPPING_H */
|