linux-stable/include/linux/fileattr.h
Christian Brauner 8782a9aea3
fs: port ->fileattr_set() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:27 +01:00

59 lines
1.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_FILEATTR_H
#define _LINUX_FILEATTR_H
/* Flags shared betwen flags/xflags */
#define FS_COMMON_FL \
(FS_SYNC_FL | FS_IMMUTABLE_FL | FS_APPEND_FL | \
FS_NODUMP_FL | FS_NOATIME_FL | FS_DAX_FL | \
FS_PROJINHERIT_FL)
#define FS_XFLAG_COMMON \
(FS_XFLAG_SYNC | FS_XFLAG_IMMUTABLE | FS_XFLAG_APPEND | \
FS_XFLAG_NODUMP | FS_XFLAG_NOATIME | FS_XFLAG_DAX | \
FS_XFLAG_PROJINHERIT)
/*
* Merged interface for miscellaneous file attributes. 'flags' originates from
* ext* and 'fsx_flags' from xfs. There's some overlap between the two, which
* is handled by the VFS helpers, so filesystems are free to implement just one
* or both of these sub-interfaces.
*/
struct fileattr {
u32 flags; /* flags (FS_IOC_GETFLAGS/FS_IOC_SETFLAGS) */
/* struct fsxattr: */
u32 fsx_xflags; /* xflags field value (get/set) */
u32 fsx_extsize; /* extsize field value (get/set)*/
u32 fsx_nextents; /* nextents field value (get) */
u32 fsx_projid; /* project identifier (get/set) */
u32 fsx_cowextsize; /* CoW extsize field value (get/set)*/
/* selectors: */
bool flags_valid:1;
bool fsx_valid:1;
};
int copy_fsxattr_to_user(const struct fileattr *fa, struct fsxattr __user *ufa);
void fileattr_fill_xflags(struct fileattr *fa, u32 xflags);
void fileattr_fill_flags(struct fileattr *fa, u32 flags);
/**
* fileattr_has_fsx - check for extended flags/attributes
* @fa: fileattr pointer
*
* Return: true if any attributes are present that are not represented in
* ->flags.
*/
static inline bool fileattr_has_fsx(const struct fileattr *fa)
{
return fa->fsx_valid &&
((fa->fsx_xflags & ~FS_XFLAG_COMMON) || fa->fsx_extsize != 0 ||
fa->fsx_projid != 0 || fa->fsx_cowextsize != 0);
}
int vfs_fileattr_get(struct dentry *dentry, struct fileattr *fa);
int vfs_fileattr_set(struct mnt_idmap *idmap, struct dentry *dentry,
struct fileattr *fa);
#endif /* _LINUX_FILEATTR_H */