fanotify: use vfs_get_fsid() helper instead of vfs_statfs()

This is a cleanup that doesn't change any logic.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 603419c..396de6e 100644 (file)
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -863,35 +863,31 @@ out_destroy_group:
 }
 
 /* Check if filesystem can encode a unique fid */
-static int fanotify_test_fid(struct path *path, struct kstatfs *stat)
+static int fanotify_test_fid(struct path *path, __kernel_fsid_t *fsid)
 {
-       struct kstatfs root_stat;
-       struct path root = {
-               .mnt = path->mnt,
-               .dentry = path->dentry->d_sb->s_root,
-       };
+       __kernel_fsid_t root_fsid;
        int err;
 
        /*
         * Make sure path is not in filesystem with zero fsid (e.g. tmpfs).
         */
-       err = vfs_statfs(path, stat);
+       err = vfs_get_fsid(path->dentry, fsid);
        if (err)
                return err;
 
-       if (!stat->f_fsid.val[0] && !stat->f_fsid.val[1])
+       if (!fsid->val[0] && !fsid->val[1])
                return -ENODEV;
 
        /*
         * Make sure path is not inside a filesystem subvolume (e.g. btrfs)
         * which uses a different fsid than sb root.
         */
-       err = vfs_statfs(&root, &root_stat);
+       err = vfs_get_fsid(path->dentry->d_sb->s_root, &root_fsid);
        if (err)
                return err;
 
-       if (root_stat.f_fsid.val[0] != stat->f_fsid.val[0] ||
-           root_stat.f_fsid.val[1] != stat->f_fsid.val[1])
+       if (root_fsid.val[0] != fsid->val[0] ||
+           root_fsid.val[1] != fsid->val[1])
                return -EXDEV;
 
        /*
@@ -916,8 +912,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
        struct fsnotify_group *group;
        struct fd f;
        struct path path;
-       struct kstatfs stat;
-       __kernel_fsid_t *fsid = NULL;
+       __kernel_fsid_t __fsid, *fsid = NULL;
        u32 valid_mask = FANOTIFY_EVENTS | FANOTIFY_EVENT_FLAGS;
        unsigned int mark_type = flags & FANOTIFY_MARK_TYPE_BITS;
        int ret;
@@ -996,11 +991,11 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
                goto fput_and_out;
 
        if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) {
-               ret = fanotify_test_fid(&path, &stat);
+               ret = fanotify_test_fid(&path, &__fsid);
                if (ret)
                        goto path_put_and_out;
 
-               fsid = &stat.f_fsid;
+               fsid = &__fsid;
        }
 
        /* inode held in place by reference to path; group by fget on fd */