ocfs2: Write support for inline data

This fixes up write, truncate, mmap, and RESVSP/UNRESVP to understand inline
inode data.

For the most part, the changes to the core write code can be relied on to do
the heavy lifting. Any code calling ocfs2_write_begin (including shared
writeable mmap) can count on it doing the right thing with respect to
growing inline data to an extent tree.

Size reducing truncates, including UNRESVP can simply zero that portion of
the inode block being removed. Size increasing truncatesm, including RESVP
have to be a little bit smarter and grow the inode to an extent tree if
necessary.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Reviewed-by: Joel Becker <joel.becker@oracle.com>
diff --git a/fs/ocfs2/alloc.h b/fs/ocfs2/alloc.h
index 990df48..826e0a6 100644
--- a/fs/ocfs2/alloc.h
+++ b/fs/ocfs2/alloc.h
@@ -62,6 +62,10 @@
 	return le16_to_cpu(fe->id2.i_list.l_tree_depth) + 2;
 }
 
+void ocfs2_set_inode_data_inline(struct inode *inode, struct ocfs2_dinode *di);
+int ocfs2_convert_inline_data_to_extents(struct inode *inode,
+					 struct buffer_head *di_bh);
+
 int ocfs2_truncate_log_init(struct ocfs2_super *osb);
 void ocfs2_truncate_log_shutdown(struct ocfs2_super *osb);
 void ocfs2_schedule_truncate_log_flush(struct ocfs2_super *osb,
@@ -115,6 +119,8 @@
 			  struct inode *inode,
 			  struct buffer_head *fe_bh,
 			  struct ocfs2_truncate_context *tc);
+int ocfs2_truncate_inline(struct inode *inode, struct buffer_head *di_bh,
+			  unsigned int start, unsigned int end, int trunc);
 
 int ocfs2_find_leaf(struct inode *inode, struct ocfs2_extent_list *root_el,
 		    u32 cpos, struct buffer_head **leaf_bh);