From 03f0e022736d123bc42907a958535f4f10d0c4c3 Mon Sep 17 00:00:00 2001
From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Date: Tue, 5 Feb 2013 11:26:28 +0530
Subject: [PATCH] fs/9p: Don't use O_TRUNC flag in TOPEN and TLOPEN request

We do the truncate via setattr request, hence don't pass the O_TRUNC flag in
open request. Without this patch we end up sending zero sized write request
to server when we try to truncate. Some servers (VirtFS) were not handling that
properly.

Reported-by: M. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
---
 fs/9p/vfs_file.c       | 4 ----
 fs/9p/vfs_inode.c      | 3 ---
 fs/9p/vfs_inode_dotl.c | 1 -
 3 files changed, 8 deletions(-)

diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index c2483e97beee9..7a3399767570b 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -80,10 +80,6 @@ int v9fs_file_open(struct inode *inode, struct file *file)
 			p9_client_clunk(fid);
 			return err;
 		}
-		if (file->f_flags & O_TRUNC) {
-			i_size_write(inode, 0);
-			inode->i_blocks = 0;
-		}
 		if ((file->f_flags & O_APPEND) &&
 			(!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)))
 			generic_file_llseek(file, 0, SEEK_END);
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 890bed538f9b6..57d017ac68e4f 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -192,9 +192,6 @@ int v9fs_uflags2omode(int uflags, int extended)
 		break;
 	}
 
-	if (uflags & O_TRUNC)
-		ret |= P9_OTRUNC;
-
 	if (extended) {
 		if (uflags & O_EXCL)
 			ret |= P9_OEXCL;
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index 40895546e103e..edd41d918e6cf 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -186,7 +186,6 @@ static int v9fs_mapped_dotl_flags(int flags)
 		{ O_CREAT,	P9_DOTL_CREATE },
 		{ O_EXCL,	P9_DOTL_EXCL },
 		{ O_NOCTTY,	P9_DOTL_NOCTTY },
-		{ O_TRUNC,	P9_DOTL_TRUNC },
 		{ O_APPEND,	P9_DOTL_APPEND },
 		{ O_NONBLOCK,	P9_DOTL_NONBLOCK },
 		{ O_DSYNC,	P9_DOTL_DSYNC },
-- 
2.30.2