diff options
| author | Miklos Szeredi <mszeredi@redhat.com> | 2024-11-12 11:10:04 +0100 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2024-11-13 17:27:02 +0100 |
| commit | 2f4d4503e9e5ab765a7948f98bc5deef7850f607 (patch) | |
| tree | 6a5bb5fb883eb226e80f47024c5a6236d7e551be /include/uapi/linux | |
| parent | 39bb1bf0b49495e70d0763a143ad889925c3d373 (diff) | |
statmount: add flag to retrieve unescaped options
Filesystem options can be retrieved with STATMOUNT_MNT_OPTS, which
returns a string of comma separated options, where some characters are
escaped using the \OOO notation.
Add a new flag, STATMOUNT_OPT_ARRAY, which instead returns the raw
option values separated with '\0' charaters.
Since escaped charaters are rare, this inteface is preferable for
non-libmount users which likley don't want to deal with option
de-escaping.
Example code:
if (st->mask & STATMOUNT_OPT_ARRAY) {
const char *opt = st->str + st->opt_array;
for (unsigned int i = 0; i < st->opt_num; i++) {
printf("opt_array[%i]: <%s>\n", i, opt);
opt += strlen(opt) + 1;
}
}
Example ouput:
(1) mnt_opts: <lowerdir+=/l\054w\054r,lowerdir+=/l\054w\054r1,upperdir=/upp\054r,workdir=/w\054rk,redirect_dir=nofollow,uuid=null>
(2) opt_array[0]: <lowerdir+=/l,w,r>
opt_array[1]: <lowerdir+=/l,w,r1>
opt_array[2]: <upperdir=/upp,r>
opt_array[3]: <workdir=/w,rk>
opt_array[4]: <redirect_dir=nofollow>
opt_array[5]: <uuid=null>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Link: https://lore.kernel.org/r/20241112101006.30715-1-mszeredi@redhat.com
Acked-by: Jeff Layton <jlayton@kernel.org>
[brauner: tweak variable naming and parsing add example output]
Signed-off-by: Christian Brauner <brauner@kernel.org>
Diffstat (limited to 'include/uapi/linux')
| -rw-r--r-- | include/uapi/linux/mount.h | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/include/uapi/linux/mount.h b/include/uapi/linux/mount.h index 2b49e9131d77..c0fda4604187 100644 --- a/include/uapi/linux/mount.h +++ b/include/uapi/linux/mount.h @@ -154,7 +154,7 @@ struct mount_attr { */ struct statmount { __u32 size; /* Total size, including strings */ - __u32 mnt_opts; /* [str] Mount options of the mount */ + __u32 mnt_opts; /* [str] Options (comma separated, escaped) */ __u64 mask; /* What results were written */ __u32 sb_dev_major; /* Device ID */ __u32 sb_dev_minor; @@ -175,7 +175,9 @@ struct statmount { __u64 mnt_ns_id; /* ID of the mount namespace */ __u32 fs_subtype; /* [str] Subtype of fs_type (if any) */ __u32 sb_source; /* [str] Source string of the mount */ - __u64 __spare2[48]; + __u32 opt_num; /* Number of fs options */ + __u32 opt_array; /* [str] Array of nul terminated fs options */ + __u64 __spare2[47]; char str[]; /* Variable size part containing strings */ }; @@ -211,6 +213,7 @@ struct mnt_id_req { #define STATMOUNT_MNT_OPTS 0x00000080U /* Want/got mnt_opts */ #define STATMOUNT_FS_SUBTYPE 0x00000100U /* Want/got fs_subtype */ #define STATMOUNT_SB_SOURCE 0x00000200U /* Want/got sb_source */ +#define STATMOUNT_OPT_ARRAY 0x00000400U /* Want/got opt_... */ /* * Special @mnt_id values that can be passed to listmount |