+ Chapter 5: Typedefs
+
+Please don't use things like "vps_t".
+
+It's a _mistake_ to use typedef for structures and pointers. When you see a
+
+ vps_t a;
+
+in the source, what does it mean?
+
+In contrast, if it says
+
+ struct virtual_container *a;
+
+you can actually tell what "a" is.
+
+Lots of people think that typedefs "help readability". Not so. They are
+useful only for:
+
+ (a) totally opaque objects (where the typedef is actively used to _hide_
+ what the object is).
+
+ Example: "pte_t" etc. opaque objects that you can only access using
+ the proper accessor functions.
+
+ NOTE! Opaqueness and "accessor functions" are not good in themselves.
+ The reason we have them for things like pte_t etc. is that there
+ really is absolutely _zero_ portably accessible information there.
+
+ (b) Clear integer types, where the abstraction _helps_ avoid confusion
+ whether it is "int" or "long".
+
+ u8/u16/u32 are perfectly fine typedefs, although they fit into
+ category (d) better than here.
+
+ NOTE! Again - there needs to be a _reason_ for this. If something is
+ "unsigned long", then there's no reason to do
+
+ typedef unsigned long myflags_t;
+
+ but if there is a clear reason for why it under certain circumstances
+ might be an "unsigned int" and under other configurations might be
+ "unsigned long", then by all means go ahead and use a typedef.
+
+ (c) when you use sparse to literally create a _new_ type for
+ type-checking.
+
+ (d) New types which are identical to standard C99 types, in certain
+ exceptional circumstances.
+
+ Although it would only take a short amount of time for the eyes and
+ brain to become accustomed to the standard types like 'uint32_t',
+ some people object to their use anyway.
+
+ Therefore, the Linux-specific 'u8/u16/u32/u64' types and their
+ signed equivalents which are identical to standard types are
+ permitted -- although they are not mandatory in new code of your
+ own.
+
+ When editing existing code which already uses one or the other set
+ of types, you should conform to the existing choices in that code.
+
+ (e) Types safe for use in userspace.
+
+ In certain structures which are visible to userspace, we cannot
+ require C99 types and cannot use the 'u32' form above. Thus, we
+ use __u32 and similar types in all structures which are shared
+ with userspace.
+
+Maybe there are other cases too, but the rule should basically be to NEVER
+EVER use a typedef unless you can clearly match one of those rules.
+
+In general, a pointer, or a struct that has elements that can reasonably
+be directly accessed should _never_ be a typedef.
+
+
+ Chapter 6: Functions