On Tue, Nov 23, 2021 at 3:29 PM Christian Brauner <brauner@xxxxxxxxxx> wrote:
>
> From: Christian Brauner <christian.brauner@xxxxxxxxxx>
>
> Since we'll be passing the filesystem's idmapping in even more places in
> the following patches and we do already dereference struct inode to get
> to the filesystem's idmapping multiple times add a tiny helper.
>
> Cc: Seth Forshee <sforshee@xxxxxxxxxxxxxxxx>
> Cc: Christoph Hellwig <hch@xxxxxx>
> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
> CC: linux-fsdevel@xxxxxxxxxxxxxxx
> Signed-off-by: Christian Brauner <christian.brauner@xxxxxxxxxx>
> ---
Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx>
> include/linux/fs.h | 13 +++++++++----
> 1 file changed, 9 insertions(+), 4 deletions(-)
>
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index 6ccb0e7f8801..c1780be923fa 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -1600,6 +1600,11 @@ struct super_block {
> struct list_head s_inodes_wb; /* writeback inodes */
> } __randomize_layout;
>
> +static inline struct user_namespace *i_user_ns(const struct inode *inode)
> +{
> + return inode->i_sb->s_user_ns;
> +}
> +
> /* Helper functions so that in most cases filesystems will
> * not need to deal directly with kuid_t and kgid_t and can
> * instead deal with the raw numeric values that are stored
> @@ -1607,22 +1612,22 @@ struct super_block {
> */
> static inline uid_t i_uid_read(const struct inode *inode)
> {
> - return from_kuid(inode->i_sb->s_user_ns, inode->i_uid);
> + return from_kuid(i_user_ns(inode), inode->i_uid);
> }
>
> static inline gid_t i_gid_read(const struct inode *inode)
> {
> - return from_kgid(inode->i_sb->s_user_ns, inode->i_gid);
> + return from_kgid(i_user_ns(inode), inode->i_gid);
> }
>
> static inline void i_uid_write(struct inode *inode, uid_t uid)
> {
> - inode->i_uid = make_kuid(inode->i_sb->s_user_ns, uid);
> + inode->i_uid = make_kuid(i_user_ns(inode), uid);
> }
>
> static inline void i_gid_write(struct inode *inode, gid_t gid)
> {
> - inode->i_gid = make_kgid(inode->i_sb->s_user_ns, gid);
> + inode->i_gid = make_kgid(i_user_ns(inode), gid);
> }
>
> /**
> --
> 2.30.2
>
