/*
- * 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
*
*/
+#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
* 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 *__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; \
+})
/**
- * kfifo_size - returns the size of the fifo in bytes
- * @fifo: the fifo to be used.
- */
-static inline __must_check unsigned int kfifo_size(struct kfifo *fifo)
+ * 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 fifo->size;
+ return val;
}
/**
- * kfifo_len - returns the number of used bytes in the FIFO
- * @fifo: the fifo to be used.
+ * 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.
*/
-static inline unsigned int kfifo_len(struct kfifo *fifo)
-{
- register unsigned int out;
-
- out = fifo->out;
- smp_rmb();
- return fifo->in - out;
-}
+#define kfifo_initialized(fifo) ((fifo)->kfifo.mask)
/**
- * kfifo_is_empty - returns true if the fifo is empty
- * @fifo: the fifo to be used.
+ * kfifo_esize - returns the size of the element managed by the fifo
+ * @fifo: address of the fifo to be used
*/
-static inline __must_check int kfifo_is_empty(struct kfifo *fifo)
-{
- return fifo->in == fifo->out;
-}
+#define kfifo_esize(fifo) ((fifo)->kfifo.esize)
/**
- * kfifo_is_full - returns true if the fifo is full
- * @fifo: the fifo to be used.
+ * kfifo_recsize - returns the size of the record length field
+ * @fifo: address of the fifo to be used
*/
-static inline __must_check int kfifo_is_full(struct kfifo *fifo)
-{
- return kfifo_len(fifo) == kfifo_size(fifo);
-}
+#define kfifo_recsize(fifo) (sizeof(*(fifo)->rectype))
/**
- * kfifo_avail - returns the number of bytes available in the FIFO
- * @fifo: the fifo to be used.
+ * kfifo_size - returns the size of the fifo in elements
+ * @fifo: address of the fifo to be used
*/
-static inline __must_check unsigned int kfifo_avail(struct kfifo *fifo)
-{
- return kfifo_size(fifo) - kfifo_len(fifo);
-}
+#define kfifo_size(fifo) ((fifo)->kfifo.mask + 1)
/**
- * kfifo_in_locked - puts some data into the FIFO using a spinlock for locking
- * @fifo: the fifo to be used.
- * @from: the data to be added.
- * @n: the length of the data to be added.
- * @lock: pointer to the spinlock to use for locking.
+ * kfifo_reset - removes the entire fifo content
+ * @fifo: address of the fifo to be used
*
- * This function copies at most @n bytes from the @from buffer into
- * the FIFO depending on the free space, and returns the number of
- * bytes copied.
+ * 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.
*/
-static inline unsigned int kfifo_in_locked(struct kfifo *fifo,
- const void *from, unsigned int n, spinlock_t *lock)
-{
- unsigned long flags;
- unsigned int ret;
-
- spin_lock_irqsave(lock, flags);
-
- ret = kfifo_in(fifo, from, n);
-
- spin_unlock_irqrestore(lock, flags);
-
- return ret;
-}
+#define kfifo_reset(fifo) \
+(void)({ \
+ typeof(fifo + 1) __tmp = (fifo); \
+ __tmp->kfifo.in = __tmp->kfifo.out = 0; \
+})
/**
- * kfifo_out_locked - gets some data from the FIFO using a spinlock for locking
- * @fifo: the fifo to be used.
- * @to: where the data must be copied.
- * @n: the size of the destination buffer.
- * @lock: pointer to the spinlock to use for locking.
+ * kfifo_reset_out - skip fifo content
+ * @fifo: address of the fifo to be used
*
- * This function copies at most @n bytes from the FIFO into the
- * @to buffer and returns the number of copied bytes.
- */
-static inline __must_check unsigned int kfifo_out_locked(struct kfifo *fifo,
- void *to, unsigned int n, spinlock_t *lock)
-{
- unsigned long flags;
- unsigned int ret;
-
- spin_lock_irqsave(lock, flags);
-
- ret = kfifo_out(fifo, to, n);
-
- spin_unlock_irqrestore(lock, flags);
-
- return ret;
-}
-
-extern void kfifo_skip(struct kfifo *fifo, unsigned int len);
-
-extern __must_check int kfifo_from_user(struct kfifo *fifo,
- const void __user *from, unsigned int n, unsigned *lenout);
-
-extern __must_check int kfifo_to_user(struct kfifo *fifo,
- void __user *to, unsigned int n, unsigned *lenout);
-
-/*
- * __kfifo_add_out internal helper function for updating the out offset
+ * 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().
*/
-static inline void __kfifo_add_out(struct kfifo *fifo,
- unsigned int off)
-{
- smp_mb();
- fifo->out += off;
-}
+#define kfifo_reset_out(fifo) \
+(void)({ \
+ typeof(fifo + 1) __tmp = (fifo); \
+ __tmp->kfifo.out = __tmp->kfifo.in; \
+})
-/*
- * __kfifo_add_in internal helper function for updating the in offset
+/**
+ * kfifo_len - returns the number of used elements in the fifo
+ * @fifo: address of the fifo to be used
*/
-static inline void __kfifo_add_in(struct kfifo *fifo,
- unsigned int off)
-{
- smp_wmb();
- fifo->in += off;
-}
+#define kfifo_len(fifo) \
+({ \
+ typeof(fifo + 1) __tmpl = (fifo); \
+ __tmpl->kfifo.in - __tmpl->kfifo.out; \
+})
-/*
- * __kfifo_off internal helper function for calculating the index of a
- * given offeset
+/**
+ * kfifo_is_empty - returns true if the fifo is empty
+ * @fifo: address of the fifo to be used
*/
-static inline unsigned int __kfifo_off(struct kfifo *fifo, unsigned int off)
-{
- return off & (fifo->size - 1);
-}
+#define kfifo_is_empty(fifo) \
+({ \
+ typeof(fifo + 1) __tmpq = (fifo); \
+ __tmpq->kfifo.in == __tmpq->kfifo.out; \
+})
-/*
- * __kfifo_peek_n internal helper function for determinate the length of
- * the next record in the fifo
+/**
+ * kfifo_is_full - returns true if the fifo is full
+ * @fifo: address of the fifo to be used
*/
-static inline unsigned int __kfifo_peek_n(struct kfifo *fifo,
- unsigned int recsize)
-{
-#define __KFIFO_GET(fifo, off, shift) \
- ((fifo)->buffer[__kfifo_off((fifo), (fifo)->out+(off))] << (shift))
+#define kfifo_is_full(fifo) \
+({ \
+ typeof(fifo + 1) __tmpq = (fifo); \
+ kfifo_len(__tmpq) > __tmpq->kfifo.mask; \
+})
- unsigned int l;
+/**
+ * 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; \
+}) \
+)
- l = __KFIFO_GET(fifo, 0, 0);
+/**
+ * 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++; \
+})
- if (--recsize)
- l |= __KFIFO_GET(fifo, 1, 8);
+/**
+ * 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); \
+}) \
+)
- return l;
-#undef __KFIFO_GET
-}
+/**
+ * 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_poke_n internal helper function for storing the length of
- * the next record into the fifo
+/**
+ * kfifo_free - frees the fifo
+ * @fifo: the fifo to be freed
*/
-static inline void __kfifo_poke_n(struct kfifo *fifo,
- unsigned int recsize, unsigned int n)
-{
-#define __KFIFO_PUT(fifo, off, val, shift) \
- ( \
- (fifo)->buffer[__kfifo_off((fifo), (fifo)->in+(off))] = \
- (unsigned char)((val) >> (shift)) \
- )
+#define kfifo_free(fifo) \
+({ \
+ typeof(fifo + 1) __tmp = (fifo); \
+ struct __kfifo *__kfifo = &__tmp->kfifo; \
+ if (__is_kfifo_ptr(__tmp)) \
+ __kfifo_free(__kfifo); \
+})
- __KFIFO_PUT(fifo, 0, n, 0);
+/**
+ * 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; \
+})
- if (--recsize)
- __KFIFO_PUT(fifo, 1, n, 8);
-#undef __KFIFO_PUT
-}
+/**
+ * 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_in_... internal functions for put date into the fifo
- * do not call it directly, use kfifo_in_rec() instead
- */
-extern unsigned int __kfifo_in_n(struct kfifo *fifo,
- const void *from, unsigned int n, unsigned int recsize);
+/**
+ * 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; \
+}) \
+)
-extern unsigned int __kfifo_in_generic(struct kfifo *fifo,
- const void *from, unsigned int n, unsigned int recsize);
+/**
+ * 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; \
+}) \
+)
-static inline unsigned int __kfifo_in_rec(struct kfifo *fifo,
- const void *from, unsigned int n, unsigned int recsize)
-{
- unsigned int 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); \
+})
- ret = __kfifo_in_n(fifo, from, n, recsize);
+/**
+ * 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)
- if (likely(ret == 0)) {
- if (recsize)
- __kfifo_poke_n(fifo, recsize, n);
- __kfifo_add_in(fifo, n + recsize);
- }
- return ret;
-}
+/**
+ * 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_in_rec - puts some record data into the FIFO
- * @fifo: the fifo to be used.
- * @from: the data to be added.
- * @n: the length of the data to be added.
- * @recsize: size of record field
+ * 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 function copies @n bytes from the @from into the FIFO and returns
- * the number of bytes which cannot be copied.
- * A returned value greater than the @n value means that the record doesn't
- * fit into the buffer.
+ * 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 functions.
- */
-static inline __must_check unsigned int kfifo_in_rec(struct kfifo *fifo,
- void *from, unsigned int n, unsigned int recsize)
-{
- if (!__builtin_constant_p(recsize))
- return __kfifo_in_generic(fifo, from, n, recsize);
- return __kfifo_in_rec(fifo, from, n, recsize);
-}
+ * 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_out_... internal functions for get date from the fifo
- * do not call it directly, use kfifo_out_rec() instead
- */
-extern unsigned int __kfifo_out_n(struct kfifo *fifo,
- void *to, unsigned int reclen, unsigned int recsize);
+/**
+ * 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); \
+})
-extern unsigned int __kfifo_out_generic(struct kfifo *fifo,
- void *to, unsigned int n,
- unsigned int recsize, unsigned int *total);
+/**
+ * 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); \
+})
-static inline unsigned int __kfifo_out_rec(struct kfifo *fifo,
- void *to, unsigned int n, unsigned int recsize,
- unsigned int *total)
-{
- unsigned int l;
-
- if (!recsize) {
- l = n;
- if (total)
- *total = l;
- } else {
- l = __kfifo_peek_n(fifo, recsize);
- if (total)
- *total = l;
- if (n < l)
- return l;
- }
+/**
+ * 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); \
+})
- return __kfifo_out_n(fifo, to, l, recsize);
-}
+/**
+ * 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_rec - gets some record data from the FIFO
- * @fifo: the fifo to be used.
- * @to: where the data must be copied.
- * @n: the size of the destination buffer.
- * @recsize: size of record field
- * @total: pointer where the total number of to copied bytes should stored
+ * 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 function copies at most @n bytes from the FIFO to @to and returns the
- * number of bytes which cannot be copied.
- * A returned value greater than the @n value means that the record doesn't
- * fit into the @to buffer.
+ * 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 functions.
+ * writer, you don't need extra locking to use these macro.
*/
-static inline __must_check unsigned int kfifo_out_rec(struct kfifo *fifo,
- void *to, unsigned int n, unsigned int recsize,
- unsigned int *total)
+#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); \
+}) \
+)
-{
- if (!__builtin_constant_p(recsize))
- return __kfifo_out_generic(fifo, to, n, recsize, total);
- return __kfifo_out_rec(fifo, to, n, recsize, total);
-}
+extern int __kfifo_alloc(struct __kfifo *fifo, unsigned int size,
+ size_t esize, gfp_t gfp_mask);
-/*
- * __kfifo_from_user_... internal functions for transfer from user space into
- * the fifo. do not call it directly, use kfifo_from_user_rec() instead
- */
-extern unsigned int __kfifo_from_user_n(struct kfifo *fifo,
- const void __user *from, unsigned int n, unsigned int recsize);
+extern void __kfifo_free(struct __kfifo *fifo);
-extern unsigned int __kfifo_from_user_generic(struct kfifo *fifo,
- const void __user *from, unsigned int n, unsigned int recsize);
+extern int __kfifo_init(struct __kfifo *fifo, void *buffer,
+ unsigned int size, size_t esize);
-static inline unsigned int __kfifo_from_user_rec(struct kfifo *fifo,
- const void __user *from, unsigned int n, unsigned int recsize)
-{
- unsigned int ret;
+extern unsigned int __kfifo_in(struct __kfifo *fifo,
+ const void *buf, unsigned int len);
- ret = __kfifo_from_user_n(fifo, from, n, recsize);
+extern unsigned int __kfifo_out(struct __kfifo *fifo,
+ void *buf, unsigned int len);
- if (likely(ret == 0)) {
- if (recsize)
- __kfifo_poke_n(fifo, recsize, n);
- __kfifo_add_in(fifo, n + recsize);
- }
- return ret;
-}
+extern int __kfifo_from_user(struct __kfifo *fifo,
+ const void __user *from, unsigned long len, unsigned int *copied);
-/**
- * kfifo_from_user_rec - puts some data from user space into the FIFO
- * @fifo: the fifo to be used.
- * @from: pointer to the data to be added.
- * @n: the length of the data to be added.
- * @recsize: size of record field
- *
- * This function copies @n bytes from the @from into the
- * FIFO and returns the number of bytes which cannot be copied.
- *
- * If the returned value is equal or less the @n value, the copy_from_user()
- * functions has failed. Otherwise the record doesn't fit into the buffer.
- *
- * Note that with only one concurrent reader and one concurrent
- * writer, you don't need extra locking to use these functions.
- */
-static inline __must_check unsigned int kfifo_from_user_rec(struct kfifo *fifo,
- const void __user *from, unsigned int n, unsigned int recsize)
-{
- if (!__builtin_constant_p(recsize))
- return __kfifo_from_user_generic(fifo, from, n, recsize);
- return __kfifo_from_user_rec(fifo, from, n, recsize);
-}
+extern int __kfifo_to_user(struct __kfifo *fifo,
+ void __user *to, unsigned long len, unsigned int *copied);
-/*
- * __kfifo_to_user_... internal functions for transfer fifo data into user space
- * do not call it directly, use kfifo_to_user_rec() instead
- */
-extern unsigned int __kfifo_to_user_n(struct kfifo *fifo,
- void __user *to, unsigned int n, unsigned int reclen,
- unsigned int recsize);
+extern unsigned int __kfifo_dma_in_prepare(struct __kfifo *fifo,
+ struct scatterlist *sgl, int nents, unsigned int len);
-extern unsigned int __kfifo_to_user_generic(struct kfifo *fifo,
- void __user *to, unsigned int n, unsigned int recsize,
- unsigned int *total);
+extern unsigned int __kfifo_dma_out_prepare(struct __kfifo *fifo,
+ struct scatterlist *sgl, int nents, unsigned int len);
-static inline unsigned int __kfifo_to_user_rec(struct kfifo *fifo,
- void __user *to, unsigned int n,
- unsigned int recsize, unsigned int *total)
-{
- unsigned int l;
-
- if (!recsize) {
- l = n;
- if (total)
- *total = l;
- } else {
- l = __kfifo_peek_n(fifo, recsize);
- if (total)
- *total = l;
- if (n < l)
- return l;
- }
+extern unsigned int __kfifo_out_peek(struct __kfifo *fifo,
+ void *buf, unsigned int len);
- return __kfifo_to_user_n(fifo, to, n, l, recsize);
-}
+extern unsigned int __kfifo_in_r(struct __kfifo *fifo,
+ const void *buf, unsigned int len, size_t recsize);
-/**
- * kfifo_to_user_rec - gets data from the FIFO and write it to user space
- * @fifo: the fifo to be used.
- * @to: where the data must be copied.
- * @n: the size of the destination buffer.
- * @recsize: size of record field
- * @total: pointer where the total number of to copied bytes should stored
- *
- * This function copies at most @n bytes from the FIFO to the @to.
- * In case of an error, the function returns the number of bytes which cannot
- * be copied.
- * If the returned value is equal or less the @n value, the copy_to_user()
- * functions has failed. Otherwise the record doesn't fit into the @to buffer.
- *
- * Note that with only one concurrent reader and one concurrent
- * writer, you don't need extra locking to use these functions.
- */
-static inline __must_check unsigned int kfifo_to_user_rec(struct kfifo *fifo,
- void __user *to, unsigned int n, unsigned int recsize,
- unsigned int *total)
-{
- if (!__builtin_constant_p(recsize))
- return __kfifo_to_user_generic(fifo, to, n, recsize, total);
- return __kfifo_to_user_rec(fifo, to, n, recsize, total);
-}
+extern unsigned int __kfifo_out_r(struct __kfifo *fifo,
+ void *buf, unsigned int len, size_t recsize);
-/*
- * __kfifo_peek_... internal functions for peek into the next fifo record
- * do not call it directly, use kfifo_peek_rec() instead
- */
-extern unsigned int __kfifo_peek_generic(struct kfifo *fifo,
- unsigned int recsize);
+extern int __kfifo_from_user_r(struct __kfifo *fifo,
+ const void __user *from, unsigned long len, unsigned int *copied,
+ size_t recsize);
-/**
- * kfifo_peek_rec - gets the size of the next FIFO record data
- * @fifo: the fifo to be used.
- * @recsize: size of record field
- *
- * This function returns the size of the next FIFO record in number of bytes
- */
-static inline __must_check unsigned int kfifo_peek_rec(struct kfifo *fifo,
- unsigned int recsize)
-{
- if (!__builtin_constant_p(recsize))
- return __kfifo_peek_generic(fifo, recsize);
- if (!recsize)
- return kfifo_len(fifo);
- return __kfifo_peek_n(fifo, recsize);
-}
+extern int __kfifo_to_user_r(struct __kfifo *fifo, void __user *to,
+ unsigned long len, unsigned int *copied, size_t recsize);
-/*
- * __kfifo_skip_... internal functions for skip the next fifo record
- * do not call it directly, use kfifo_skip_rec() instead
- */
-extern void __kfifo_skip_generic(struct kfifo *fifo, unsigned int recsize);
+extern unsigned int __kfifo_dma_in_prepare_r(struct __kfifo *fifo,
+ struct scatterlist *sgl, int nents, unsigned int len, size_t recsize);
-static inline void __kfifo_skip_rec(struct kfifo *fifo,
- unsigned int recsize)
-{
- unsigned int l;
+extern void __kfifo_dma_in_finish_r(struct __kfifo *fifo,
+ unsigned int len, size_t recsize);
- if (recsize) {
- l = __kfifo_peek_n(fifo, recsize);
+extern unsigned int __kfifo_dma_out_prepare_r(struct __kfifo *fifo,
+ struct scatterlist *sgl, int nents, unsigned int len, size_t recsize);
- if (l + recsize <= kfifo_len(fifo)) {
- __kfifo_add_out(fifo, l + recsize);
- return;
- }
- }
- kfifo_reset_out(fifo);
-}
+extern void __kfifo_dma_out_finish_r(struct __kfifo *fifo, size_t recsize);
-/**
- * kfifo_skip_rec - skip the next fifo out record
- * @fifo: the fifo to be used.
- * @recsize: size of record field
- *
- * This function skips the next FIFO record
- */
-static inline void kfifo_skip_rec(struct kfifo *fifo,
- unsigned int recsize)
-{
- if (!__builtin_constant_p(recsize))
- __kfifo_skip_generic(fifo, recsize);
- else
- __kfifo_skip_rec(fifo, recsize);
-}
+extern unsigned int __kfifo_len_r(struct __kfifo *fifo, size_t recsize);
-/**
- * kfifo_avail_rec - returns the number of bytes available in a record FIFO
- * @fifo: the fifo to be used.
- * @recsize: size of record field
- */
-static inline __must_check unsigned int kfifo_avail_rec(struct kfifo *fifo,
- unsigned int recsize)
-{
- unsigned int l = kfifo_size(fifo) - kfifo_len(fifo);
+extern void __kfifo_skip_r(struct __kfifo *fifo, size_t recsize);
- return (l > recsize) ? l - recsize : 0;
-}
+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
projects / karo-tx-linux.git / blobdiff