kfifo: replace the old non generic API

Simply replace the whole kfifo.c and kfifo.h files with the new generic
version and fix the kerneldoc API template file.

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 711 insertions, 1326 deletions

diff --git a/include/linux/kfifo-new.h b/include/linux/kfifo-new.h
deleted file mode 100644
index 311f8753d71..00000000000
--- a/include/linux/kfifo-new.h
+++ /dev/null
@@ -1,844 +0,0 @@
-/*
- * A generic kernel FIFO implementation
- *
- * Copyright (C) 2009/2010 Stefani Seibold <stefani@seibold.net>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- */
-
-#ifndef _LINUX_KFIFO_H
-#define _LINUX_KFIFO_H
-
-/*
- * How to porting drivers to the new generic FIFO API:
- *
- * - Modify the declaration of the "struct kfifo *" object into a
- *   in-place "struct kfifo" object
- * - Init the in-place object with kfifo_alloc() or kfifo_init()
- *   Note: The address of the in-place "struct kfifo" object must be
- *   passed as the first argument to this functions
- * - Replace the use of __kfifo_put into kfifo_in and __kfifo_get
- *   into kfifo_out
- * - Replace the use of kfifo_put into kfifo_in_spinlocked and kfifo_get
- *   into kfifo_out_spinlocked
- *   Note: the spinlock pointer formerly passed to kfifo_init/kfifo_alloc
- *   must be passed now to the kfifo_in_spinlocked and kfifo_out_spinlocked
- *   as the last parameter
- * - The formerly __kfifo_* functions are renamed into kfifo_*
- */
-
-/*
- * Note about locking : There is no locking required until only * one reader
- * and one writer is using the fifo and no kfifo_reset() will be * called
- *  kfifo_reset_out() can be safely used, until it will be only called
- * in the reader thread.
- *  For multiple writer and one reader there is only a need to lock the writer.
- * And vice versa for only one writer and multiple reader there is only a need
- * to lock the reader.
- */
-
-#include <linux/kernel.h>
-#include <linux/spinlock.h>
-#include <linux/stddef.h>
-#include <linux/scatterlist.h>
-
-struct __kfifo {
-	unsigned int	in;
-	unsigned int	out;
-	unsigned int	mask;
-	unsigned int	esize;
-	void		*data;
-};
-
-#define __STRUCT_KFIFO_COMMON(datatype, recsize, ptrtype) \
-	union { \
-		struct __kfifo	kfifo; \
-		datatype	*type; \
-		char		(*rectype)[recsize]; \
-		ptrtype		*ptr; \
-		const ptrtype	*ptr_const; \
-	}
-
-#define __STRUCT_KFIFO(type, size, recsize, ptrtype) \
-{ \
-	__STRUCT_KFIFO_COMMON(type, recsize, ptrtype); \
-	type		buf[((size < 2) || (size & (size - 1))) ? -1 : size]; \
-}
-
-#define STRUCT_KFIFO(type, size) \
-	struct __STRUCT_KFIFO(type, size, 0, type)
-
-#define __STRUCT_KFIFO_PTR(type, recsize, ptrtype) \
-{ \
-	__STRUCT_KFIFO_COMMON(type, recsize, ptrtype); \
-	type		buf[0]; \
-}
-
-#define STRUCT_KFIFO_PTR(type) \
-	struct __STRUCT_KFIFO_PTR(type, 0, type)
-
-/*
- * define compatibility "struct kfifo" for dynamic allocated fifos
- */
-struct kfifo __STRUCT_KFIFO_PTR(unsigned char, 0, void);
-
-#define STRUCT_KFIFO_REC_1(size) \
-	struct __STRUCT_KFIFO(unsigned char, size, 1, void)
-
-#define STRUCT_KFIFO_REC_2(size) \
-	struct __STRUCT_KFIFO(unsigned char, size, 2, void)
-
-/*
- * define kfifo_rec types
- */
-struct kfifo_rec_ptr_1 __STRUCT_KFIFO_PTR(unsigned char, 1, void);
-struct kfifo_rec_ptr_2 __STRUCT_KFIFO_PTR(unsigned char, 2, void);
-
-/*
- * helper macro to distinguish between real in place fifo where the fifo
- * array is a part of the structure and the fifo type where the array is
- * outside of the fifo structure.
- */
-#define	__is_kfifo_ptr(fifo)	(sizeof(*fifo) == sizeof(struct __kfifo))
-
-/**
- * DECLARE_KFIFO_PTR - macro to declare a fifo pointer object
- * @fifo: name of the declared fifo
- * @type: type of the fifo elements
- */
-#define DECLARE_KFIFO_PTR(fifo, type)	STRUCT_KFIFO_PTR(type) fifo
-
-/**
- * DECLARE_KFIFO - macro to declare a fifo object
- * @fifo: name of the declared fifo
- * @type: type of the fifo elements
- * @size: the number of elements in the fifo, this must be a power of 2
- */
-#define DECLARE_KFIFO(fifo, type, size)	STRUCT_KFIFO(type, size) fifo
-
-/**
- * INIT_KFIFO - Initialize a fifo declared by DECLARE_KFIFO
- * @fifo: name of the declared fifo datatype
- */
-#define INIT_KFIFO(fifo) \
-(void)({ \
-	typeof(&(fifo)) __tmp = &(fifo); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	__kfifo->in = 0; \
-	__kfifo->out = 0; \
-	__kfifo->mask = __is_kfifo_ptr(__tmp) ? 0 : ARRAY_SIZE(__tmp->buf) - 1;\
-	__kfifo->esize = sizeof(*__tmp->buf); \
-	__kfifo->data = __is_kfifo_ptr(__tmp) ?  NULL : __tmp->buf; \
-})
-
-/**
- * DEFINE_KFIFO - macro to define and initialize a fifo
- * @fifo: name of the declared fifo datatype
- * @type: type of the fifo elements
- * @size: the number of elements in the fifo, this must be a power of 2
- *
- * Note: the macro can be used for global and local fifo data type variables.
- */
-#define DEFINE_KFIFO(fifo, type, size) \
-	DECLARE_KFIFO(fifo, type, size) = \
-	(typeof(fifo)) { \
-		{ \
-			{ \
-			.in	= 0, \
-			.out	= 0, \
-			.mask	= __is_kfifo_ptr(&(fifo)) ? \
-				  0 : \
-				  ARRAY_SIZE((fifo).buf) - 1, \
-			.esize	= sizeof(*(fifo).buf), \
-			.data	= __is_kfifo_ptr(&(fifo)) ? \
-				NULL : \
-				(fifo).buf, \
-			} \
-		} \
-	}
-
-
-static inline unsigned int __must_check
-__kfifo_must_check_helper(unsigned int val)
-{
-	return val;
-}
-
-/**
- * kfifo_initialized - Check if the fifo is initialized
- * @fifo: address of the fifo to check
- *
- * Return %true if fifo is initialized, otherwise %false.
- * Assumes the fifo was 0 before.
- */
-#define kfifo_initialized(fifo) ((fifo)->kfifo.mask)
-
-/**
- * kfifo_esize - returns the size of the element managed by the fifo
- * @fifo: address of the fifo to be used
- */
-#define kfifo_esize(fifo)	((fifo)->kfifo.esize)
-
-/**
- * kfifo_recsize - returns the size of the record length field
- * @fifo: address of the fifo to be used
- */
-#define kfifo_recsize(fifo)	(sizeof(*(fifo)->rectype))
-
-/**
- * kfifo_size - returns the size of the fifo in elements
- * @fifo: address of the fifo to be used
- */
-#define kfifo_size(fifo)	((fifo)->kfifo.mask + 1)
-
-/**
- * kfifo_reset - removes the entire fifo content
- * @fifo: address of the fifo to be used
- *
- * Note: usage of kfifo_reset() is dangerous. It should be only called when the
- * fifo is exclusived locked or when it is secured that no other thread is
- * accessing the fifo.
- */
-#define kfifo_reset(fifo) \
-(void)({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	__tmp->kfifo.in = __tmp->kfifo.out = 0; \
-})
-
-/**
- * kfifo_reset_out - skip fifo content
- * @fifo: address of the fifo to be used
- *
- * Note: The usage of kfifo_reset_out() is safe until it will be only called
- * from the reader thread and there is only one concurrent reader. Otherwise
- * it is dangerous and must be handled in the same way as kfifo_reset().
- */
-#define kfifo_reset_out(fifo)	\
-(void)({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	__tmp->kfifo.out = __tmp->kfifo.in; \
-})
-
-/**
- * kfifo_len - returns the number of used elements in the fifo
- * @fifo: address of the fifo to be used
- */
-#define kfifo_len(fifo) \
-({ \
-	typeof(fifo + 1) __tmpl = (fifo); \
-	__tmpl->kfifo.in - __tmpl->kfifo.out; \
-})
-
-/**
- * kfifo_is_empty - returns true if the fifo is empty
- * @fifo: address of the fifo to be used
- */
-#define	kfifo_is_empty(fifo) \
-({ \
-	typeof(fifo + 1) __tmpq = (fifo); \
-	__tmpq->kfifo.in == __tmpq->kfifo.out; \
-})
-
-/**
- * kfifo_is_full - returns true if the fifo is full
- * @fifo: address of the fifo to be used
- */
-#define	kfifo_is_full(fifo) \
-({ \
-	typeof(fifo + 1) __tmpq = (fifo); \
-	kfifo_len(__tmpq) > __tmpq->kfifo.mask; \
-})
-
-/**
- * kfifo_avail - returns the number of unused elements in the fifo
- * @fifo: address of the fifo to be used
- */
-#define	kfifo_avail(fifo) \
-__kfifo_must_check_helper( \
-({ \
-	typeof(fifo + 1) __tmpq = (fifo); \
-	const size_t __recsize = sizeof(*__tmpq->rectype); \
-	unsigned int __avail = kfifo_size(__tmpq) - kfifo_len(__tmpq); \
-	(__recsize) ? ((__avail <= __recsize) ? 0 : \
-	__kfifo_max_r(__avail - __recsize, __recsize)) : \
-	__avail; \
-}) \
-)
-
-/**
- * kfifo_skip - skip output data
- * @fifo: address of the fifo to be used
- */
-#define	kfifo_skip(fifo) \
-(void)({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	const size_t __recsize = sizeof(*__tmp->rectype); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	if (__recsize) \
-		__kfifo_skip_r(__kfifo, __recsize); \
-	else \
-		__kfifo->out++; \
-})
-
-/**
- * kfifo_peek_len - gets the size of the next fifo record
- * @fifo: address of the fifo to be used
- *
- * This function returns the size of the next fifo record in number of bytes.
- */
-#define kfifo_peek_len(fifo) \
-__kfifo_must_check_helper( \
-({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	const size_t __recsize = sizeof(*__tmp->rectype); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	(!__recsize) ? kfifo_len(__tmp) * sizeof(*__tmp->type) : \
-	__kfifo_len_r(__kfifo, __recsize); \
-}) \
-)
-
-/**
- * kfifo_alloc - dynamically allocates a new fifo buffer
- * @fifo: pointer to the fifo
- * @size: the number of elements in the fifo, this must be a power of 2
- * @gfp_mask: get_free_pages mask, passed to kmalloc()
- *
- * This macro dynamically allocates a new fifo buffer.
- *
- * The numer of elements will be rounded-up to a power of 2.
- * The fifo will be release with kfifo_free().
- * Return 0 if no error, otherwise an error code.
- */
-#define kfifo_alloc(fifo, size, gfp_mask) \
-__kfifo_must_check_helper( \
-({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	__is_kfifo_ptr(__tmp) ? \
-	__kfifo_alloc(__kfifo, size, sizeof(*__tmp->type), gfp_mask) : \
-	-EINVAL; \
-}) \
-)
-
-/**
- * kfifo_free - frees the fifo
- * @fifo: the fifo to be freed
- */
-#define kfifo_free(fifo) \
-({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	if (__is_kfifo_ptr(__tmp)) \
-		__kfifo_free(__kfifo); \
-})
-
-/**
- * kfifo_init - initialize a fifo using a preallocated buffer
- * @fifo: the fifo to assign the buffer
- * @buffer: the preallocated buffer to be used
- * @size: the size of the internal buffer, this have to be a power of 2
- *
- * This macro initialize a fifo using a preallocated buffer.
- *
- * The numer of elements will be rounded-up to a power of 2.
- * Return 0 if no error, otherwise an error code.
- */
-#define kfifo_init(fifo, buffer, size) \
-({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	__is_kfifo_ptr(__tmp) ? \
-	__kfifo_init(__kfifo, buffer, size, sizeof(*__tmp->type)) : \
-	-EINVAL; \
-})
-
-/**
- * kfifo_put - put data into the fifo
- * @fifo: address of the fifo to be used
- * @val: the data to be added
- *
- * This macro copies the given value into the fifo.
- * It returns 0 if the fifo was full. Otherwise it returns the number
- * processed elements.
- *
- * Note that with only one concurrent reader and one concurrent
- * writer, you don't need extra locking to use these macro.
- */
-#define	kfifo_put(fifo, val) \
-({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	typeof(val + 1) __val = (val); \
-	unsigned int __ret; \
-	const size_t __recsize = sizeof(*__tmp->rectype); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	if (0) { \
-		typeof(__tmp->ptr_const) __dummy __attribute__ ((unused)); \
-		__dummy = (typeof(__val))NULL; \
-	} \
-	if (__recsize) \
-		__ret = __kfifo_in_r(__kfifo, __val, sizeof(*__val), \
-			__recsize); \
-	else { \
-		__ret = !kfifo_is_full(__tmp); \
-		if (__ret) { \
-			(__is_kfifo_ptr(__tmp) ? \
-			((typeof(__tmp->type))__kfifo->data) : \
-			(__tmp->buf) \
-			)[__kfifo->in & __tmp->kfifo.mask] = \
-				*(typeof(__tmp->type))__val; \
-			smp_wmb(); \
-			__kfifo->in++; \
-		} \
-	} \
-	__ret; \
-})
-
-/**
- * kfifo_get - get data from the fifo
- * @fifo: address of the fifo to be used
- * @val: the var where to store the data to be added
- *
- * This macro reads the data from the fifo.
- * It returns 0 if the fifo was empty. Otherwise it returns the number
- * processed elements.
- *
- * Note that with only one concurrent reader and one concurrent
- * writer, you don't need extra locking to use these macro.
- */
-#define	kfifo_get(fifo, val) \
-__kfifo_must_check_helper( \
-({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	typeof(val + 1) __val = (val); \
-	unsigned int __ret; \
-	const size_t __recsize = sizeof(*__tmp->rectype); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	if (0) \
-		__val = (typeof(__tmp->ptr))0; \
-	if (__recsize) \
-		__ret = __kfifo_out_r(__kfifo, __val, sizeof(*__val), \
-			__recsize); \
-	else { \
-		__ret = !kfifo_is_empty(__tmp); \
-		if (__ret) { \
-			*(typeof(__tmp->type))__val = \
-				(__is_kfifo_ptr(__tmp) ? \
-				((typeof(__tmp->type))__kfifo->data) : \
-				(__tmp->buf) \
-				)[__kfifo->out & __tmp->kfifo.mask]; \
-			smp_wmb(); \
-			__kfifo->out++; \
-		} \
-	} \
-	__ret; \
-}) \
-)
-
-/**
- * kfifo_peek - get data from the fifo without removing
- * @fifo: address of the fifo to be used
- * @val: the var where to store the data to be added
- *
- * This reads the data from the fifo without removing it from the fifo.
- * It returns 0 if the fifo was empty. Otherwise it returns the number
- * processed elements.
- *
- * Note that with only one concurrent reader and one concurrent
- * writer, you don't need extra locking to use these macro.
- */
-#define	kfifo_peek(fifo, val) \
-__kfifo_must_check_helper( \
-({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	typeof(val + 1) __val = (val); \
-	unsigned int __ret; \
-	const size_t __recsize = sizeof(*__tmp->rectype); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	if (0) \
-		__val = (typeof(__tmp->ptr))NULL; \
-	if (__recsize) \
-		__ret = __kfifo_out_peek_r(__kfifo, __val, sizeof(*__val), \
-			__recsize); \
-	else { \
-		__ret = !kfifo_is_empty(__tmp); \
-		if (__ret) { \
-			*(typeof(__tmp->type))__val = \
-				(__is_kfifo_ptr(__tmp) ? \
-				((typeof(__tmp->type))__kfifo->data) : \
-				(__tmp->buf) \
-				)[__kfifo->out & __tmp->kfifo.mask]; \
-			smp_wmb(); \
-		} \
-	} \
-	__ret; \
-}) \
-)
-
-/**
- * kfifo_in - put data into the fifo
- * @fifo: address of the fifo to be used
- * @buf: the data to be added
- * @n: number of elements to be added
- *
- * This macro copies the given buffer into the fifo and returns the
- * number of copied elements.
- *
- * Note that with only one concurrent reader and one concurrent
- * writer, you don't need extra locking to use these macro.
- */
-#define	kfifo_in(fifo, buf, n) \
-({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	typeof(buf + 1) __buf = (buf); \
-	unsigned long __n = (n); \
-	const size_t __recsize = sizeof(*__tmp->rectype); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	if (0) { \
-		typeof(__tmp->ptr_const) __dummy __attribute__ ((unused)); \
-		__dummy = (typeof(__buf))NULL; \
-	} \
-	(__recsize) ?\
-	__kfifo_in_r(__kfifo, __buf, __n, __recsize) : \
-	__kfifo_in(__kfifo, __buf, __n); \
-})
-
-/**
- * kfifo_in_spinlocked - put data into the fifo using a spinlock for locking
- * @fifo: address of the fifo to be used
- * @buf: the data to be added
- * @n: number of elements to be added
- * @lock: pointer to the spinlock to use for locking
- *
- * This macro copies the given values buffer into the fifo and returns the
- * number of copied elements.
- */
-#define	kfifo_in_spinlocked(fifo, buf, n, lock) \
-({ \
-	unsigned long __flags; \
-	unsigned int __ret; \
-	spin_lock_irqsave(lock, __flags); \
-	__ret = kfifo_in(fifo, buf, n); \
-	spin_unlock_irqrestore(lock, __flags); \
-	__ret; \
-})
-
-/* alias for kfifo_in_spinlocked, will be removed in a future release */
-#define kfifo_in_locked(fifo, buf, n, lock) \
-		kfifo_in_spinlocked(fifo, buf, n, lock)
-
-/**
- * kfifo_out - get data from the fifo
- * @fifo: address of the fifo to be used
- * @buf: pointer to the storage buffer
- * @n: max. number of elements to get
- *
- * This macro get some data from the fifo and return the numbers of elements
- * copied.
- *
- * Note that with only one concurrent reader and one concurrent
- * writer, you don't need extra locking to use these macro.
- */
-#define	kfifo_out(fifo, buf, n) \
-__kfifo_must_check_helper( \
-({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	typeof(buf + 1) __buf = (buf); \
-	unsigned long __n = (n); \
-	const size_t __recsize = sizeof(*__tmp->rectype); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	if (0) { \
-		typeof(__tmp->ptr) __dummy = NULL; \
-		__buf = __dummy; \
-	} \
-	(__recsize) ?\
-	__kfifo_out_r(__kfifo, __buf, __n, __recsize) : \
-	__kfifo_out(__kfifo, __buf, __n); \
-}) \
-)
-
-/**
- * kfifo_out_spinlocked - get data from the fifo using a spinlock for locking
- * @fifo: address of the fifo to be used
- * @buf: pointer to the storage buffer
- * @n: max. number of elements to get
- * @lock: pointer to the spinlock to use for locking
- *
- * This macro get the data from the fifo and return the numbers of elements
- * copied.
- */
-#define	kfifo_out_spinlocked(fifo, buf, n, lock) \
-__kfifo_must_check_helper( \
-({ \
-	unsigned long __flags; \
-	unsigned int __ret; \
-	spin_lock_irqsave(lock, __flags); \
-	__ret = kfifo_out(fifo, buf, n); \
-	spin_unlock_irqrestore(lock, __flags); \
-	__ret; \
-}) \
-)
-
-/* alias for kfifo_out_spinlocked, will be removed in a future release */
-#define kfifo_out_locked(fifo, buf, n, lock) \
-		kfifo_out_spinlocked(fifo, buf, n, lock)
-
-/**
- * kfifo_from_user - puts some data from user space into the fifo
- * @fifo: address of the fifo to be used
- * @from: pointer to the data to be added
- * @len: the length of the data to be added
- * @copied: pointer to output variable to store the number of copied bytes
- *
- * This macro copies at most @len bytes from the @from into the
- * fifo, depending of the available space and returns -EFAULT/0.
- *
- * Note that with only one concurrent reader and one concurrent
- * writer, you don't need extra locking to use these macro.
- */
-#define	kfifo_from_user(fifo, from, len, copied) \
-__kfifo_must_check_helper( \
-({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	const void __user *__from = (from); \
-	unsigned int __len = (len); \
-	unsigned int *__copied = (copied); \
-	const size_t __recsize = sizeof(*__tmp->rectype); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	(__recsize) ? \
-	__kfifo_from_user_r(__kfifo, __from, __len,  __copied, __recsize) : \
-	__kfifo_from_user(__kfifo, __from, __len, __copied); \
-}) \
-)
-
-/**
- * kfifo_to_user - copies data from the fifo into user space
- * @fifo: address of the fifo to be used
- * @to: where the data must be copied
- * @len: the size of the destination buffer
- * @copied: pointer to output variable to store the number of copied bytes
- *
- * This macro copies at most @len bytes from the fifo into the
- * @to buffer and returns -EFAULT/0.
- *
- * Note that with only one concurrent reader and one concurrent
- * writer, you don't need extra locking to use these macro.
- */
-#define	kfifo_to_user(fifo, to, len, copied) \
-__kfifo_must_check_helper( \
-({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	void __user *__to = (to); \
-	unsigned int __len = (len); \
-	unsigned int *__copied = (copied); \
-	const size_t __recsize = sizeof(*__tmp->rectype); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	(__recsize) ? \
-	__kfifo_to_user_r(__kfifo, __to, __len, __copied, __recsize) : \
-	__kfifo_to_user(__kfifo, __to, __len, __copied); \
-}) \
-)
-
-/**
- * kfifo_dma_in_prepare - setup a scatterlist for DMA input
- * @fifo: address of the fifo to be used
- * @sgl: pointer to the scatterlist array
- * @nents: number of entries in the scatterlist array
- * @len: number of elements to transfer
- *
- * This macro fills a scatterlist for DMA input.
- * It returns the number entries in the scatterlist array.
- *
- * Note that with only one concurrent reader and one concurrent
- * writer, you don't need extra locking to use these macros.
- */
-#define	kfifo_dma_in_prepare(fifo, sgl, nents, len) \
-({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	struct scatterlist *__sgl = (sgl); \
-	int __nents = (nents); \
-	unsigned int __len = (len); \
-	const size_t __recsize = sizeof(*__tmp->rectype); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	(__recsize) ? \
-	__kfifo_dma_in_prepare_r(__kfifo, __sgl, __nents, __len, __recsize) : \
-	__kfifo_dma_in_prepare(__kfifo, __sgl, __nents, __len); \
-})
-
-/**
- * kfifo_dma_in_finish - finish a DMA IN operation
- * @fifo: address of the fifo to be used
- * @len: number of bytes to received
- *
- * This macro finish a DMA IN operation. The in counter will be updated by
- * the len parameter. No error checking will be done.
- *
- * Note that with only one concurrent reader and one concurrent
- * writer, you don't need extra locking to use these macros.
- */
-#define kfifo_dma_in_finish(fifo, len) \
-(void)({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	unsigned int __len = (len); \
-	const size_t __recsize = sizeof(*__tmp->rectype); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	if (__recsize) \
-		__kfifo_dma_in_finish_r(__kfifo, __len, __recsize); \
-	else \
-		__kfifo->in += __len / sizeof(*__tmp->type); \
-})
-
-/**
- * kfifo_dma_out_prepare - setup a scatterlist for DMA output
- * @fifo: address of the fifo to be used
- * @sgl: pointer to the scatterlist array
- * @nents: number of entries in the scatterlist array
- * @len: number of elements to transfer
- *
- * This macro fills a scatterlist for DMA output which at most @len bytes
- * to transfer.
- * It returns the number entries in the scatterlist array.
- * A zero means there is no space available and the scatterlist is not filled.
- *
- * Note that with only one concurrent reader and one concurrent
- * writer, you don't need extra locking to use these macros.
- */
-#define	kfifo_dma_out_prepare(fifo, sgl, nents, len) \
-({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	struct scatterlist *__sgl = (sgl); \
-	int __nents = (nents); \
-	unsigned int __len = (len); \
-	const size_t __recsize = sizeof(*__tmp->rectype); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	(__recsize) ? \
-	__kfifo_dma_out_prepare_r(__kfifo, __sgl, __nents, __len, __recsize) : \
-	__kfifo_dma_out_prepare(__kfifo, __sgl, __nents, __len); \
-})
-
-/**
- * kfifo_dma_out_finish - finish a DMA OUT operation
- * @fifo: address of the fifo to be used
- * @len: number of bytes transferd
- *
- * This macro finish a DMA OUT operation. The out counter will be updated by
- * the len parameter. No error checking will be done.
- *
- * Note that with only one concurrent reader and one concurrent
- * writer, you don't need extra locking to use these macros.
- */
-#define kfifo_dma_out_finish(fifo, len) \
-(void)({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	unsigned int __len = (len); \
-	const size_t __recsize = sizeof(*__tmp->rectype); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	if (__recsize) \
-		__kfifo_dma_out_finish_r(__kfifo, __recsize); \
-	else \
-		__kfifo->out += __len / sizeof(*__tmp->type); \
-})
-
-/**
- * kfifo_out_peek - gets some data from the fifo
- * @fifo: address of the fifo to be used
- * @buf: pointer to the storage buffer
- * @n: max. number of elements to get
- *
- * This macro get the data from the fifo and return the numbers of elements
- * copied. The data is not removed from the fifo.
- *
- * Note that with only one concurrent reader and one concurrent
- * writer, you don't need extra locking to use these macro.
- */
-#define	kfifo_out_peek(fifo, buf, n) \
-__kfifo_must_check_helper( \
-({ \
-	typeof(fifo + 1) __tmp = (fifo); \
-	typeof(buf + 1) __buf = (buf); \
-	unsigned long __n = (n); \
-	const size_t __recsize = sizeof(*__tmp->rectype); \
-	struct __kfifo *__kfifo = &__tmp->kfifo; \
-	if (0) { \
-		typeof(__tmp->ptr) __dummy __attribute__ ((unused)) = NULL; \
-		__buf = __dummy; \
-	} \
-	(__recsize) ? \
-	__kfifo_out_peek_r(__kfifo, __buf, __n, __recsize) : \
-	__kfifo_out_peek(__kfifo, __buf, __n); \
-}) \
-)
-
-extern int __kfifo_alloc(struct __kfifo *fifo, unsigned int size,
-	size_t esize, gfp_t gfp_mask);
-
-extern void __kfifo_free(struct __kfifo *fifo);
-
-extern int __kfifo_init(struct __kfifo *fifo, void *buffer,
-	unsigned int size, size_t esize);
-
-extern unsigned int __kfifo_in(struct __kfifo *fifo,
-	const void *buf, unsigned int len);
-
-extern unsigned int __kfifo_out(struct __kfifo *fifo,
-	void *buf, unsigned int len);
-
-extern int __kfifo_from_user(struct __kfifo *fifo,
-	const void __user *from, unsigned long len, unsigned int *copied);
-
-extern int __kfifo_to_user(struct __kfifo *fifo,
-	void __user *to, unsigned long len, unsigned int *copied);
-
-extern unsigned int __kfifo_dma_in_prepare(struct __kfifo *fifo,
-	struct scatterlist *sgl, int nents, unsigned int len);
-
-extern unsigned int __kfifo_dma_out_prepare(struct __kfifo *fifo,
-	struct scatterlist *sgl, int nents, unsigned int len);
-
-extern unsigned int __kfifo_out_peek(struct __kfifo *fifo,
-	void *buf, unsigned int len);
-
-extern unsigned int __kfifo_in_r(struct __kfifo *fifo,
-	const void *buf, unsigned int len, size_t recsize);
-
-extern unsigned int __kfifo_out_r(struct __kfifo *fifo,
-	void *buf, unsigned int len, size_t recsize);
-
-extern int __kfifo_from_user_r(struct __kfifo *fifo,
-	const void __user *from, unsigned long len, unsigned int *copied,
-	size_t recsize);
-
-extern int __kfifo_to_user_r(struct __kfifo *fifo, void __user *to,
-	unsigned long len, unsigned int *copied, size_t recsize);
-
-extern unsigned int __kfifo_dma_in_prepare_r(struct __kfifo *fifo,
-	struct scatterlist *sgl, int nents, unsigned int len, size_t recsize);
-
-extern void __kfifo_dma_in_finish_r(struct __kfifo *fifo,
-	unsigned int len, size_t recsize);
-
-extern unsigned int __kfifo_dma_out_prepare_r(struct __kfifo *fifo,
-	struct scatterlist *sgl, int nents, unsigned int len, size_t recsize);
-
-extern void __kfifo_dma_out_finish_r(struct __kfifo *fifo, size_t recsize);
-
-extern unsigned int __kfifo_len_r(struct __kfifo *fifo, size_t recsize);
-
-extern unsigned int __kfifo_out_peek_r(struct __kfifo *fifo,
-	void *buf, unsigned int len, size_t recsize);
-
-extern unsigned int __kfifo_max_r(unsigned int len, size_t recsize);
-
-#endif
diff --git a/include/linux/kfifo.h b/include/linux/kfifo.h
index 57c4eedf4dd..311f8753d71 100644
--- a/include/linux/kfifo.h
+++ b/include/linux/kfifo.h
@@ -1,8 +1,7 @@
 /*
- * A generic kernel FIFO implementation.
+ * A generic kernel FIFO implementation
  *
- * Copyright (C) 2009 Stefani Seibold <stefani@seibold.net>
- * Copyright (C) 2004 Stelian Pop <stelian@popies.net>
+ * Copyright (C) 2009/2010 Stefani Seibold <stefani@seibold.net>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -20,8 +19,11 @@
  *
  */
 
+#ifndef _LINUX_KFIFO_H
+#define _LINUX_KFIFO_H
+
 /*
- * Howto porting drivers to the new generic fifo API:
+ * How to porting drivers to the new generic FIFO API:
  *
  * - Modify the declaration of the "struct kfifo *" object into a
  *   in-place "struct kfifo" object
@@ -30,586 +32,813 @@
  *   passed as the first argument to this functions
  * - Replace the use of __kfifo_put into kfifo_in and __kfifo_get
  *   into kfifo_out
- * - Replace the use of kfifo_put into kfifo_in_locked and kfifo_get
- *   into kfifo_out_locked
+ * - Replace the use of kfifo_put into kfifo_in_spinlocked and kfifo_get
+ *   into kfifo_out_spinlocked
  *   Note: the spinlock pointer formerly passed to kfifo_init/kfifo_alloc
- *   must be passed now to the kfifo_in_locked and kfifo_out_locked
- *   as the last parameter.
- * - All formerly name __kfifo_* functions has been renamed into kfifo_*
+ *   must be passed now to the kfifo_in_spinlocked and kfifo_out_spinlocked
+ *   as the last parameter
+ * - The formerly __kfifo_* functions are renamed into kfifo_*
  */
 
-#ifndef _LINUX_KFIFO_H
-#define _LINUX_KFIFO_H
+/*
+ * Note about locking : There is no locking required until only * one reader
+ * and one writer is using the fifo and no kfifo_reset() will be * called
+ *  kfifo_reset_out() can be safely used, until it will be only called
+ * in the reader thread.
+ *  For multiple writer and one reader there is only a need to lock the writer.
+ * And vice versa for only one writer and multiple reader there is only a need
+ * to lock the reader.
+ */
 
 #include <linux/kernel.h>
 #include <linux/spinlock.h>
-
-struct kfifo {
-	unsigned char *buffer;	/* the buffer holding the data */
-	unsigned int size;	/* the size of the allocated buffer */
-	unsigned int in;	/* data is added at offset (in % size) */
-	unsigned int out;	/* data is extracted from off. (out % size) */
+#include <linux/stddef.h>
+#include <linux/scatterlist.h>
+
+struct __kfifo {
+	unsigned int	in;
+	unsigned int	out;
+	unsigned int	mask;
+	unsigned int	esize;
+	void		*data;
 };
 
-/*
- * Macros for declaration and initialization of the kfifo datatype
- */
-
-/* helper macro */
-#define __kfifo_initializer(s, b) \
-	(struct kfifo) { \
-		.size	= s, \
-		.in	= 0, \
-		.out	= 0, \
-		.buffer = b \
+#define __STRUCT_KFIFO_COMMON(datatype, recsize, ptrtype) \
+	union { \
+		struct __kfifo	kfifo; \
+		datatype	*type; \
+		char		(*rectype)[recsize]; \
+		ptrtype		*ptr; \
+		const ptrtype	*ptr_const; \
 	}
 
-/**
- * DECLARE_KFIFO - macro to declare a kfifo and the associated buffer
- * @name: name of the declared kfifo datatype
- * @size: size of the fifo buffer. Must be a power of two.
- *
- * Note1: the macro can be used inside struct or union declaration
- * Note2: the macro creates two objects:
- *  A kfifo object with the given name and a buffer for the kfifo
- *  object named name##kfifo_buffer
- */
-#define DECLARE_KFIFO(name, size) \
-union { \
-	struct kfifo name; \
-	unsigned char name##kfifo_buffer[size + sizeof(struct kfifo)]; \
+#define __STRUCT_KFIFO(type, size, recsize, ptrtype) \
+{ \
+	__STRUCT_KFIFO_COMMON(type, recsize, ptrtype); \
+	type		buf[((size < 2) || (size & (size - 1))) ? -1 : size]; \
 }
 
-/**
- * INIT_KFIFO - Initialize a kfifo declared by DECLARE_KFIFO
- * @name: name of the declared kfifo datatype
+#define STRUCT_KFIFO(type, size) \
+	struct __STRUCT_KFIFO(type, size, 0, type)
+
+#define __STRUCT_KFIFO_PTR(type, recsize, ptrtype) \
+{ \
+	__STRUCT_KFIFO_COMMON(type, recsize, ptrtype); \
+	type		buf[0]; \
+}
+
+#define STRUCT_KFIFO_PTR(type) \
+	struct __STRUCT_KFIFO_PTR(type, 0, type)
+
+/*
+ * define compatibility "struct kfifo" for dynamic allocated fifos
  */
-#define INIT_KFIFO(name) \
-	name = __kfifo_initializer(sizeof(name##kfifo_buffer) - \
-				sizeof(struct kfifo), \
-				name##kfifo_buffer + sizeof(struct kfifo))
+struct kfifo __STRUCT_KFIFO_PTR(unsigned char, 0, void);
 
-/**
- * DEFINE_KFIFO - macro to define and initialize a kfifo
- * @name: name of the declared kfifo datatype
- * @size: size of the fifo buffer. Must be a power of two.
- *
- * Note1: the macro can be used for global and local kfifo data type variables
- * Note2: the macro creates two objects:
- *  A kfifo object with the given name and a buffer for the kfifo
- *  object named name##kfifo_buffer
+#define STRUCT_KFIFO_REC_1(size) \
+	struct __STRUCT_KFIFO(unsigned char, size, 1, void)
+
+#define STRUCT_KFIFO_REC_2(size) \
+	struct __STRUCT_KFIFO(unsigned char, size, 2, void)
+
+/*
+ * define kfifo_rec types
  */
-#define DEFINE_KFIFO(name, size) \
-	unsigned char name##kfifo_buffer[size]; \
-	struct kfifo name = __kfifo_initializer(size, name##kfifo_buffer)
+struct kfifo_rec_ptr_1 __STRUCT_KFIFO_PTR(unsigned char, 1, void);
+struct kfifo_rec_ptr_2 __STRUCT_KFIFO_PTR(unsigned char, 2, void);
 
-extern void kfifo_init(struct kfifo *fifo, void *buffer,
-			unsigned int size);
-extern __must_check int kfifo_alloc(struct kfifo *fifo, unsigned int size,
-			gfp_t gfp_mask);
-extern void kfifo_free(struct kfifo *fifo);
-extern unsigned int kfifo_in(struct kfifo *fifo,
-				const void *from, unsigned int len);
-extern __must_check unsigned int kfifo_out(struct kfifo *fifo,
-				void *to, unsigned int len);
-extern __must_check unsigned int kfifo_out_peek(struct kfifo *fifo,
-				void *to, unsigned int len, unsigned offset);
+/*
+ * helper macro to distinguish between real in place fifo where the fifo
+ * array is a part of the structure and the fifo type where the array is
+ * outside of the fifo structure.
+ */
+#define	__is_kfifo_ptr(fifo)	(sizeof(*fifo) == sizeof(struct __kfifo))
 
 /**
- * kfifo_initialized - Check if kfifo is initialized.
- * @fifo: fifo to check
- * Return %true if FIFO is initialized, otherwise %false.
- * Assumes the fifo was 0 before.
+ * DECLARE_KFIFO_PTR - macro to declare a fifo pointer object
+ * @fifo: name of the declared fifo
+ * @type: type of the fifo elements
  */
-static inline bool kfifo_initialized(struct kfifo *fifo)
-{
-	return fifo->buffer != NULL;
-}
+#define DECLARE_KFIFO_PTR(fifo, type)	STRUCT_KFIFO_PTR(type) fifo
 
 /**
- * kfifo_reset - removes the entire FIFO contents
- * @fifo: the fifo to be emptied.
+ * DECLARE_KFIFO - macro to declare a fifo object
+ * @fifo: name of the declared fifo
+ * @type: type of the fifo elements
+ * @size: the number of elements in the fifo, this must be a power of 2
  */
-static inline void kfifo_reset(struct kfifo *fifo)
-{
-	fifo->in = fifo->out = 0;
-}
+#define DECLARE_KFIFO(fifo, type, size)	STRUCT_KFIFO(type, size) fifo
 
 /**
- * kfifo_reset_out - skip FIFO contents
- * @fifo: the fifo to be emptied.
- */
-static inline void kfifo_reset_out(struct kfifo *fifo)
-{
-	smp_mb();
-	fifo->out = fifo->in;
-}
+ * INIT_KFIFO - Initialize a fifo declared by DECLARE_KFIFO
+ * @fifo: name of the declared fifo datatype
+ */
+#define INIT_KFIFO(fifo) \
+(void)({ \
+	typeof(&(fifo)) __tmp = &(fifo); \
+	struct __kfifo