[PATCH 16/25] elevate writer count for do_sys_truncate()

[Dave Hansen]

Signed-off-by: Dave Hansen <haveblue at us.ibm.com>
---

 lxc-dave/fs/open.c |   16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff -puN fs/open.c~15-24-elevate-writer-count-for-do-sys-truncate fs/open.c
--- lxc/fs/open.c~15-24-elevate-writer-count-for-do-sys-truncate	2006-12-11 14:22:07.000000000 -0800
+++ lxc-dave/fs/open.c	2006-12-11 14:22:07.000000000 -0800
@@ -241,28 +241,32 @@ static long do_sys_truncate(const char _
 	if (!S_ISREG(inode->i_mode))
 		goto dput_and_out;
 
-	error = vfs_permission(&nd, MAY_WRITE);
+	error = mnt_want_write(nd.mnt);
 	if (error)
 		goto dput_and_out;
 
+	error = vfs_permission(&nd, MAY_WRITE);
+	if (error)
+		goto mnt_drop_write_and_out;
+
 	error = -EROFS;
 	if (IS_RDONLY(inode))
-		goto dput_and_out;
+		goto mnt_drop_write_and_out;
 
 	error = -EPERM;
 	if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
-		goto dput_and_out;
+		goto mnt_drop_write_and_out;
 
 	/*
 	 * Make sure that there are no leases.
 	 */
 	error = break_lease(inode, FMODE_WRITE);
 	if (error)
-		goto dput_and_out;
+		goto mnt_drop_write_and_out;
 
 	error = get_write_access(inode);
 	if (error)
-		goto dput_and_out;
+		goto mnt_drop_write_and_out;
 
 	error = locks_verify_truncate(inode, NULL, length);
 	if (!error) {
@@ -271,6 +275,8 @@ static long do_sys_truncate(const char _
 	}
 	put_write_access(inode);
 
+mnt_drop_write_and_out:
+	mnt_drop_write(nd.mnt);
 dput_and_out:
 	path_release(&nd);
 out:
_