%Data Types
%Thadeu Cascardo

# Macros

* include/linux/kernel.h
* ARRAY\\_SIZE
* FIELD\\_SIZEOF
* ALIGN
* PTR\\_ALIGN
* IS\\_ALIGNED

# More macros

* container\\_of
* offsetof

# krefs

Reference:

* Documentation/kref.txt

# API

* struct kref
* kref\\_init - struct kref pointer
* kref\\_get - struct kref pointer
* kref\\_put - struct kref pointer and release function

# Usage

* Embed struct kref into your own structure
* Do not forget to call kref\\_init when initializing your structure
* Pass a release function as parameter to kref\\_put, where you release your
  structure
* Follow the rules for calling kref\\_get and kref\\_put

# Rules

* Must increment count if passing a non-temporary copy
* May increment count without a lock if already has a valid pointer
* Must decrement when done with the pointer
* If code never tries to get a ref without a valid pointer, may be done without
  a lock
* Must serialize getting a ref without a valid pointer with putting a ref

# Endianness

# Lists

# Bitmaps

# Trees and hashes

# Other data types