From: Younger Liu <younger.liu@huawei.com>
Date: Thu, 27 Jun 2013 23:51:08 +0000 (+1000)
Subject: ocfs2: fix issue that ocfs2_setattr() does not deal with new_i_size==i_size
X-Git-Tag: next-20130628~3^2~627
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=04c96e42d517dd53525cdb9bdcdedc2cb7fb44d3;p=karo-tx-linux.git

ocfs2: fix issue that ocfs2_setattr() does not deal with new_i_size==i_size

The issue scenario is as following:

1. fallocate a large disk space(eg.  30G) with FALLOC_FL_KEEP_SIZE for
   a file whose i_size and disk size are 512(or other size).  After
   executing fallocate, i_size file is still 512, and the disk size became
   to 30G+512；

2. ftruncate the file to new_i_size which equal to inode->i_size.
   After executing ftruncate, disk space does not changes.  In other
   words, i_size file is still 512, and disk size is 30G+512.  But we want
   disk size to be 512.  This does not meet our expectations.

In order to solve the issue above, we modified ocfs2_setattr().  If
attr->ia_size != i_size_read(inode), it calls ocfs2_truncate_file(), and
truncate disk space to attr->ia_size.

Signed-off-by: Younger Liu <younger.liu@huawei.com>
Cc: Jie Liu <jeff.liu@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Sunil Mushran <sunil.mushran@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 17e6bdde96c5..2fc6779655e6 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -7126,7 +7126,7 @@ int ocfs2_truncate_inline(struct inode *inode, struct buffer_head *di_bh,
 	if (end > i_size_read(inode))
 		end = i_size_read(inode);
 
-	BUG_ON(start >= end);
+	BUG_ON(start > end);
 
 	if (!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) ||
 	    !(le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_DATA_FL) ||
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 86669958efe2..f25177fedd99 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -476,9 +476,6 @@ static int ocfs2_truncate_file(struct inode *inode,
 
 	/* lets handle the simple truncate cases before doing any more
 	 * cluster locking. */
-	if (new_i_size == le64_to_cpu(fe->i_size))
-		goto bail;
-
 	down_write(&OCFS2_I(inode)->ip_alloc_sem);
 
 	ocfs2_resv_discard(&osb->osb_la_resmap,
@@ -1150,14 +1147,14 @@ int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
 		goto bail_unlock_rw;
 	}
 
-	if (size_change && attr->ia_size != i_size_read(inode)) {
+	if (size_change) {
 		status = inode_newsize_ok(inode, attr->ia_size);
 		if (status)
 			goto bail_unlock;
 
 		inode_dio_wait(inode);
 
-		if (i_size_read(inode) > attr->ia_size) {
+		if (i_size_read(inode) >= attr->ia_size) {
 			if (ocfs2_should_order_data(inode)) {
 				status = ocfs2_begin_ordered_truncate(inode,
 								      attr->ia_size);