ceph: Fix incorrect flush end position calculation

In ceph, in fill_fscrypt_truncate(), the end flush position is calculated
by:

                loff_t lend = orig_pos + CEPH_FSCRYPT_BLOCK_SHIFT - 1;

but that's using the block shift not the block size.

Fix this to use the block size instead.

Fixes: 5c64737 ("ceph: add truncate size handling support for fscrypt")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Author: dhowells

fs/ceph/inode.c

@@ -2362,7 +2362,7 @@ static int fill_fscrypt_truncate(struct inode *inode,
 
 	/* Try to writeback the dirty pagecaches */
 	if (issued & (CEPH_CAP_FILE_BUFFER)) {
-		loff_t lend = orig_pos + CEPH_FSCRYPT_BLOCK_SHIFT - 1;
+		loff_t lend = orig_pos + CEPH_FSCRYPT_BLOCK_SIZE - 1;
 
 		ret = filemap_write_and_wait_range(inode->i_mapping,
 						   orig_pos, lend);