introduce a macro for max file size, instead of hardcoding it; ok

millert@

2 files changed, 11 insertions, 3 deletions

diff --git a/sys/ufs/ffs/ffs_vfsops.c b/sys/ufs/ffs/ffs_vfsops.c
index f0bd52cbeb3..20dea16eafd 100644
--- a/sys/ufs/ffs/ffs_vfsops.c
+++ b/sys/ufs/ffs/ffs_vfsops.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ffs_vfsops.c,v 1.117 2008/09/12 12:27:27 blambert Exp $	*/
+/*	$OpenBSD: ffs_vfsops.c,v 1.118 2008/11/02 08:53:06 otto Exp $	*/
 /*	$NetBSD: ffs_vfsops.c,v 1.19 1996/02/09 22:22:26 christos Exp $	*/
 
 /*
@@ -892,7 +892,7 @@ ffs_mountfs(struct vnode *devvp, struct mount *mp, struct proc *p)
 	 * a little added paranoia never hurts.
 	 */
 	ump->um_savedmaxfilesize = fs->fs_maxfilesize;		/* XXX */
-	maxfilesize = (u_int64_t)0x80000000 * MIN(PAGE_SIZE, fs->fs_bsize) - 1;
+	maxfilesize = FS_KERNMAXFILESIZE(fs);
 	if (fs->fs_maxfilesize > maxfilesize)			/* XXX */
 		fs->fs_maxfilesize = maxfilesize;		/* XXX */
 	if (ronly == 0) {
diff --git a/sys/ufs/ffs/fs.h b/sys/ufs/ffs/fs.h
index da799a11497..8acb0db3c5c 100644
--- a/sys/ufs/ffs/fs.h
+++ b/sys/ufs/ffs/fs.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: fs.h,v 1.33 2008/01/05 19:49:26 otto Exp $	*/
+/*	$OpenBSD: fs.h,v 1.34 2008/11/02 08:53:06 otto Exp $	*/
 /*	$NetBSD: fs.h,v 1.6 1995/04/12 21:21:02 mycroft Exp $	*/
 
 /*
@@ -575,5 +575,13 @@ struct ocg {
  */
 #define	NINDIR(fs)	((fs)->fs_nindir)
 
+/* Maximum file size the kernel allows.
+ * Even though ffs can handle files up to 16TB, we do limit the max file
+ * to 2^31 pages to prevent overflow of a 32-bit unsigned int.  The buffer
+ * cache has its own checks but a little added paranoia never hurts.
+ */
+#define FS_KERNMAXFILESIZE(fs)	((u_int64_t)0x80000000 * \
+    MIN(PAGE_SIZE, (fs)->fs_bsize) - 1)
+
 extern const int inside[], around[];
 extern const u_char *fragtbl[];