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| author | Miklos Szeredi <mszeredi@redhat.com> | 2020-05-14 16:44:24 +0200 |
|---|---|---|
| committer | Miklos Szeredi <mszeredi@redhat.com> | 2020-05-14 16:44:24 +0200 |
| commit | 80340fe3605c0e78cfe496c3b3878be828cfdbfe (patch) | |
| tree | a579a0172a6e31a9fe0b11c186f130a4fe9479a6 | |
| parent | fa2fcf4f1df1559a0a4ee0f46915b496cc2ebf60 (diff) | |
| download | linux-80340fe3605c0e78cfe496c3b3878be828cfdbfe.tar.bz2 | |
statx: add mount_root
Determining whether a path or file descriptor refers to a mountpoint (or
more precisely a mount root) is not trivial using current tools.
Add a flag to statx that indicates whether the path or fd refers to the
root of a mount or not.
Cc: linux-api@vger.kernel.org
Cc: linux-man@vger.kernel.org
Reported-by: Lennart Poettering <mzxreary@0pointer.de>
Reported-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
| -rw-r--r-- | fs/stat.c | 3 | ||||
| -rw-r--r-- | include/uapi/linux/stat.h | 1 |
2 files changed, 4 insertions, 0 deletions
diff --git a/fs/stat.c b/fs/stat.c index 3d88c99f7743..b9faa6cafafe 100644 --- a/fs/stat.c +++ b/fs/stat.c @@ -202,6 +202,9 @@ retry: error = vfs_getattr(&path, stat, request_mask, flags); stat->mnt_id = real_mount(path.mnt)->mnt_id; stat->result_mask |= STATX_MNT_ID; + if (path.mnt->mnt_root == path.dentry) + stat->attributes |= STATX_ATTR_MOUNT_ROOT; + stat->attributes_mask |= STATX_ATTR_MOUNT_ROOT; path_put(&path); if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; diff --git a/include/uapi/linux/stat.h b/include/uapi/linux/stat.h index d81456247f10..6df9348bb277 100644 --- a/include/uapi/linux/stat.h +++ b/include/uapi/linux/stat.h @@ -181,6 +181,7 @@ struct statx { #define STATX_ATTR_NODUMP 0x00000040 /* [I] File is not to be dumped */ #define STATX_ATTR_ENCRYPTED 0x00000800 /* [I] File requires key to decrypt in fs */ #define STATX_ATTR_AUTOMOUNT 0x00001000 /* Dir: Automount trigger */ +#define STATX_ATTR_MOUNT_ROOT 0x00002000 /* Root of a mount */ #define STATX_ATTR_VERITY 0x00100000 /* [I] Verity protected file */ |