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 17e6bdde96c5e4707a29906e207e981761ca49c8..2fc6779655e6571acdeabe14839419a0cf779513 100644 (file)
--- 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 86669958efe2d916ed358389ef9f647a41ce7168..f25177fedd9983079f5a23583e7d98f1a441e1b6 100644 (file)
--- 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);