[src/trunk]: src/sys/ufs/ffs allow also the snapshot_setup()'s call to ffs_tr...

[jdolecek <jdolecek%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/f0ec5d868008
branches:  trunk
changeset: 348500:f0ec5d868008
user:      jdolecek <jdolecek%NetBSD.org@localhost>
date:      Thu Oct 20 20:17:46 2016 +0000

description:
allow also the snapshot_setup()'s call to ffs_truncate() fail, the code
should simply reuse the file blocks in that case; also make sure the
ffs_truncate() call is run within transaction if log is on

diffstat:

 sys/ufs/ffs/ffs_snapshot.c |  19 ++++++++++++++-----
 1 files changed, 14 insertions(+), 5 deletions(-)

diffs (54 lines):

diff -r 42a45d10452a -r f0ec5d868008 sys/ufs/ffs/ffs_snapshot.c
--- a/sys/ufs/ffs/ffs_snapshot.c        Thu Oct 20 19:31:32 2016 +0000
+++ b/sys/ufs/ffs/ffs_snapshot.c        Thu Oct 20 20:17:46 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ffs_snapshot.c,v 1.140 2015/06/28 10:04:32 maxv Exp $  */
+/*     $NetBSD: ffs_snapshot.c,v 1.141 2016/10/20 20:17:46 jdolecek Exp $      */
 
 /*
  * Copyright 2000 Marshall Kirk McKusick. All Rights Reserved.
@@ -38,7 +38,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ffs_snapshot.c,v 1.140 2015/06/28 10:04:32 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ffs_snapshot.c,v 1.141 2016/10/20 20:17:46 jdolecek Exp $");
 
 #if defined(_KERNEL_OPT)
 #include "opt_ffs.h"
@@ -402,6 +402,10 @@
        }
        if (error) {
                if (UFS_WAPBL_BEGIN(mp) == 0) {
+                       /*
+                        * This is okay to fail, we'll simply reuse the blocks
+                        * later.
+                        */
                        (void) ffs_truncate(vp, (off_t)0, 0, NOCRED);
                        UFS_WAPBL_END(mp);
                }
@@ -437,9 +441,13 @@
                return EACCES;
 
        if (vp->v_size != 0) {
-               error = ffs_truncate(vp, 0, 0, NOCRED);
-               if (error)
-                       return error;
+               if (UFS_WAPBL_BEGIN(mp) == 0) {
+                       /*
+                        * This is okay to fail, we'll simply reuse the blocks
+                        */
+                       (void) ffs_truncate(vp, 0, 0, NOCRED);
+                       UFS_WAPBL_END(mp);
+               }
        }
 
        /* Change inode to snapshot type file. */
@@ -448,6 +456,7 @@
                return error;
 #if defined(QUOTA) || defined(QUOTA2)
        /* shapshot inodes are not accounted in quotas */
+       chkdq(ip, -DIP(ip, blocks), l->l_cred, 0);
        chkiq(ip, -1, l->l_cred, 0);
 #endif
        ip->i_flags |= (SF_SNAPSHOT | SF_SNAPINVAL);