ocfs2: Support xfs style space reservation ioctls

We re-use the RESVSP/UNRESVSP ioctls from xfs which allow the user to
allocate and deallocate regions to a file without zeroing data or changing
i_size.

Though renamed, the structure passed in from user is identical to struct
xfs_flock64. The three fields that are actually used right now are l_whence,
l_start and l_len.

This should get ocfs2 immediate compatibility with userspace software using
the pre-existing xfs ioctls.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/fs/ocfs2/file.h b/fs/ocfs2/file.h
index 79115c92dc30..36fe27f268ee 100644
--- a/fs/ocfs2/file.h
+++ b/fs/ocfs2/file.h
@@ -62,4 +62,7 @@ int ocfs2_should_update_atime(struct inode *inode,
 int ocfs2_update_inode_atime(struct inode *inode,
                              struct buffer_head *bh);
 
+int ocfs2_change_file_space(struct file *file, unsigned int cmd,
+                            struct ocfs2_space_resv *sr);
+
 #endif /* OCFS2_FILE_H */