fstat patch (64-bit os, zfs or devfs)

What do you think about the following change?

commit c6d04723027dbc493376b6fd058bd7875ec8a888
Author: Andriy Gapon <avg_at_icyb.net.ua>
Date:   Fri Jun 12 19:16:45 2009 +0300

    fstat: fix fsid comparison when executed on a file on 64-bit system

    This affects only fstat on zfs and devfs, only on 64-bit systems
    and only when fsid is greater than 2^31 - 1.
    When fstat examines a file via stat(2) it takes uint32_t st_dev
    and assigns to (signed) (64-bit) long fsid, this results in
    a positive value.
    When fstat examines opened files it takes int32_t f_fsid.val[0]
    and assigns to (signed) (64-bit) long fsid, this results in
    a negative value.
    So, while initially st_dev and f_fsid.val[0] have the same bit
    values they get promoted to different 64-bit values because
    of the signed-vs-unsigned difference.

    A fix is to use "more natural" positive numbers by introducing
    intermediate unsigned cast for f_fsid.val[0].

diff --git a/usr.bin/fstat/fstat.c b/usr.bin/fstat/fstat.c
index 0907c49..dc728e5 100644
--- a/usr.bin/fstat/fstat.c
+++ b/usr.bin/fstat/fstat.c
_at__at_ -649,7 +649,7 _at__at_ devfs_filestat(struct vnode *vp, struct filestat *fsp)
 		    (void *)devfs_dirent.de_vnode, Pid);
 		return 0;
 	}
-	fsp->fsid = (long)mount.mnt_stat.f_fsid.val[0];
+	fsp->fsid = (long)(uint32_t)mount.mnt_stat.f_fsid.val[0];
 	fsp->fileid = devfs_dirent.de_inode;
 	fsp->mode = (devfs_dirent.de_mode & ~S_IFMT) | S_IFCHR;
 	fsp->size = 0;
diff --git a/usr.bin/fstat/zfs.c b/usr.bin/fstat/zfs.c
index f611b1c..f654e79 100644
--- a/usr.bin/fstat/zfs.c
+++ b/usr.bin/fstat/zfs.c
_at__at_ -117,7 +117,7 _at__at_ zfs_filestat(struct vnode *vp, struct filestat *fsp)
 		goto bad;
 	}

-	fsp->fsid = (long)mount.mnt_stat.f_fsid.val[0];
+	fsp->fsid = (long)(uint32_t)mount.mnt_stat.f_fsid.val[0];
 	fsp->fileid = *zid;
 	/*
 	 * XXX: Shows up wrong in output, but UFS has this error too. Could

-- 
Andriy Gapon