835 lines
25 KiB
C
835 lines
25 KiB
C
/*
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* A generic kernel FIFO implementation
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*
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* Copyright (C) 2013 Stefani Seibold <stefani@seibold.net>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*
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*/
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#ifndef _LINUX_KFIFO_H
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#define _LINUX_KFIFO_H
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/*
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* How to porting drivers to the new generic FIFO API:
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*
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* - Modify the declaration of the "struct kfifo *" object into a
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* in-place "struct kfifo" object
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* - Init the in-place object with kfifo_alloc() or kfifo_init()
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* Note: The address of the in-place "struct kfifo" object must be
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* passed as the first argument to this functions
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* - Replace the use of __kfifo_put into kfifo_in and __kfifo_get
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* into kfifo_out
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* - Replace the use of kfifo_put into kfifo_in_spinlocked and kfifo_get
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* into kfifo_out_spinlocked
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* Note: the spinlock pointer formerly passed to kfifo_init/kfifo_alloc
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* must be passed now to the kfifo_in_spinlocked and kfifo_out_spinlocked
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* as the last parameter
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* - The formerly __kfifo_* functions are renamed into kfifo_*
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*/
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/*
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* Note about locking: There is no locking required until only one reader
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* and one writer is using the fifo and no kfifo_reset() will be called.
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* kfifo_reset_out() can be safely used, until it will be only called
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* in the reader thread.
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* For multiple writer and one reader there is only a need to lock the writer.
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* And vice versa for only one writer and multiple reader there is only a need
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* to lock the reader.
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*/
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#include <linux/kernel.h>
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#include <linux/spinlock.h>
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#include <linux/stddef.h>
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#include <linux/scatterlist.h>
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struct __kfifo {
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unsigned int in;
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unsigned int out;
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unsigned int mask;
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unsigned int esize;
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void *data;
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};
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#define __STRUCT_KFIFO_COMMON(datatype, recsize, ptrtype) \
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union { \
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struct __kfifo kfifo; \
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datatype *type; \
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const datatype *const_type; \
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char (*rectype)[recsize]; \
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ptrtype *ptr; \
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ptrtype const *ptr_const; \
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}
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#define __STRUCT_KFIFO(type, size, recsize, ptrtype) \
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{ \
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__STRUCT_KFIFO_COMMON(type, recsize, ptrtype); \
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type buf[((size < 2) || (size & (size - 1))) ? -1 : size]; \
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}
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#define STRUCT_KFIFO(type, size) \
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struct __STRUCT_KFIFO(type, size, 0, type)
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#define __STRUCT_KFIFO_PTR(type, recsize, ptrtype) \
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{ \
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__STRUCT_KFIFO_COMMON(type, recsize, ptrtype); \
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type buf[0]; \
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}
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#define STRUCT_KFIFO_PTR(type) \
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struct __STRUCT_KFIFO_PTR(type, 0, type)
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/*
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* define compatibility "struct kfifo" for dynamic allocated fifos
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*/
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struct kfifo __STRUCT_KFIFO_PTR(unsigned char, 0, void);
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#define STRUCT_KFIFO_REC_1(size) \
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struct __STRUCT_KFIFO(unsigned char, size, 1, void)
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#define STRUCT_KFIFO_REC_2(size) \
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struct __STRUCT_KFIFO(unsigned char, size, 2, void)
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/*
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* define kfifo_rec types
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*/
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struct kfifo_rec_ptr_1 __STRUCT_KFIFO_PTR(unsigned char, 1, void);
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struct kfifo_rec_ptr_2 __STRUCT_KFIFO_PTR(unsigned char, 2, void);
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/*
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* helper macro to distinguish between real in place fifo where the fifo
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* array is a part of the structure and the fifo type where the array is
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* outside of the fifo structure.
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*/
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#define __is_kfifo_ptr(fifo) \
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(sizeof(*fifo) == sizeof(STRUCT_KFIFO_PTR(typeof(*(fifo)->type))))
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/**
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* DECLARE_KFIFO_PTR - macro to declare a fifo pointer object
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* @fifo: name of the declared fifo
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* @type: type of the fifo elements
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*/
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#define DECLARE_KFIFO_PTR(fifo, type) STRUCT_KFIFO_PTR(type) fifo
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/**
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* DECLARE_KFIFO - macro to declare a fifo object
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* @fifo: name of the declared fifo
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* @type: type of the fifo elements
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* @size: the number of elements in the fifo, this must be a power of 2
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*/
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#define DECLARE_KFIFO(fifo, type, size) STRUCT_KFIFO(type, size) fifo
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/**
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* INIT_KFIFO - Initialize a fifo declared by DECLARE_KFIFO
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* @fifo: name of the declared fifo datatype
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*/
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#define INIT_KFIFO(fifo) \
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(void)({ \
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typeof(&(fifo)) __tmp = &(fifo); \
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struct __kfifo *__kfifo = &__tmp->kfifo; \
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__kfifo->in = 0; \
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__kfifo->out = 0; \
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__kfifo->mask = __is_kfifo_ptr(__tmp) ? 0 : ARRAY_SIZE(__tmp->buf) - 1;\
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__kfifo->esize = sizeof(*__tmp->buf); \
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__kfifo->data = __is_kfifo_ptr(__tmp) ? NULL : __tmp->buf; \
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})
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/**
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* DEFINE_KFIFO - macro to define and initialize a fifo
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* @fifo: name of the declared fifo datatype
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* @type: type of the fifo elements
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* @size: the number of elements in the fifo, this must be a power of 2
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*
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* Note: the macro can be used for global and local fifo data type variables.
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*/
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#define DEFINE_KFIFO(fifo, type, size) \
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DECLARE_KFIFO(fifo, type, size) = \
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(typeof(fifo)) { \
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{ \
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{ \
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.in = 0, \
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.out = 0, \
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.mask = __is_kfifo_ptr(&(fifo)) ? \
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0 : \
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ARRAY_SIZE((fifo).buf) - 1, \
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.esize = sizeof(*(fifo).buf), \
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.data = __is_kfifo_ptr(&(fifo)) ? \
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NULL : \
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(fifo).buf, \
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} \
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} \
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}
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static inline unsigned int __must_check
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__kfifo_uint_must_check_helper(unsigned int val)
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{
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return val;
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}
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static inline int __must_check
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__kfifo_int_must_check_helper(int val)
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{
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return val;
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}
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/**
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* kfifo_initialized - Check if the fifo is initialized
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* @fifo: address of the fifo to check
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*
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* Return %true if fifo is initialized, otherwise %false.
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* Assumes the fifo was 0 before.
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*/
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#define kfifo_initialized(fifo) ((fifo)->kfifo.mask)
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/**
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* kfifo_esize - returns the size of the element managed by the fifo
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* @fifo: address of the fifo to be used
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*/
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#define kfifo_esize(fifo) ((fifo)->kfifo.esize)
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/**
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* kfifo_recsize - returns the size of the record length field
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* @fifo: address of the fifo to be used
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*/
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#define kfifo_recsize(fifo) (sizeof(*(fifo)->rectype))
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/**
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* kfifo_size - returns the size of the fifo in elements
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* @fifo: address of the fifo to be used
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*/
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#define kfifo_size(fifo) ((fifo)->kfifo.mask + 1)
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/**
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* kfifo_reset - removes the entire fifo content
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* @fifo: address of the fifo to be used
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*
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* Note: usage of kfifo_reset() is dangerous. It should be only called when the
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* fifo is exclusived locked or when it is secured that no other thread is
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* accessing the fifo.
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*/
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#define kfifo_reset(fifo) \
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(void)({ \
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typeof((fifo) + 1) __tmp = (fifo); \
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__tmp->kfifo.in = __tmp->kfifo.out = 0; \
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})
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/**
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* kfifo_reset_out - skip fifo content
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* @fifo: address of the fifo to be used
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*
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* Note: The usage of kfifo_reset_out() is safe until it will be only called
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* from the reader thread and there is only one concurrent reader. Otherwise
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* it is dangerous and must be handled in the same way as kfifo_reset().
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*/
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#define kfifo_reset_out(fifo) \
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(void)({ \
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typeof((fifo) + 1) __tmp = (fifo); \
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__tmp->kfifo.out = __tmp->kfifo.in; \
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})
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/**
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* kfifo_len - returns the number of used elements in the fifo
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* @fifo: address of the fifo to be used
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*/
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#define kfifo_len(fifo) \
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({ \
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typeof((fifo) + 1) __tmpl = (fifo); \
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__tmpl->kfifo.in - __tmpl->kfifo.out; \
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})
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/**
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* kfifo_is_empty - returns true if the fifo is empty
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* @fifo: address of the fifo to be used
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*/
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#define kfifo_is_empty(fifo) \
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({ \
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typeof((fifo) + 1) __tmpq = (fifo); \
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__tmpq->kfifo.in == __tmpq->kfifo.out; \
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})
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/**
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* kfifo_is_full - returns true if the fifo is full
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* @fifo: address of the fifo to be used
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*/
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#define kfifo_is_full(fifo) \
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({ \
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typeof((fifo) + 1) __tmpq = (fifo); \
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kfifo_len(__tmpq) > __tmpq->kfifo.mask; \
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})
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/**
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* kfifo_avail - returns the number of unused elements in the fifo
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* @fifo: address of the fifo to be used
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*/
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#define kfifo_avail(fifo) \
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__kfifo_uint_must_check_helper( \
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({ \
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typeof((fifo) + 1) __tmpq = (fifo); \
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const size_t __recsize = sizeof(*__tmpq->rectype); \
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unsigned int __avail = kfifo_size(__tmpq) - kfifo_len(__tmpq); \
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(__recsize) ? ((__avail <= __recsize) ? 0 : \
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__kfifo_max_r(__avail - __recsize, __recsize)) : \
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__avail; \
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}) \
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)
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/**
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* kfifo_skip - skip output data
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* @fifo: address of the fifo to be used
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*/
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#define kfifo_skip(fifo) \
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(void)({ \
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typeof((fifo) + 1) __tmp = (fifo); \
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const size_t __recsize = sizeof(*__tmp->rectype); \
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struct __kfifo *__kfifo = &__tmp->kfifo; \
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if (__recsize) \
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__kfifo_skip_r(__kfifo, __recsize); \
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else \
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__kfifo->out++; \
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})
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/**
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* kfifo_peek_len - gets the size of the next fifo record
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* @fifo: address of the fifo to be used
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*
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* This function returns the size of the next fifo record in number of bytes.
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*/
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#define kfifo_peek_len(fifo) \
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__kfifo_uint_must_check_helper( \
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({ \
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typeof((fifo) + 1) __tmp = (fifo); \
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const size_t __recsize = sizeof(*__tmp->rectype); \
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struct __kfifo *__kfifo = &__tmp->kfifo; \
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(!__recsize) ? kfifo_len(__tmp) * sizeof(*__tmp->type) : \
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__kfifo_len_r(__kfifo, __recsize); \
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}) \
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)
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/**
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* kfifo_alloc - dynamically allocates a new fifo buffer
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* @fifo: pointer to the fifo
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* @size: the number of elements in the fifo, this must be a power of 2
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* @gfp_mask: get_free_pages mask, passed to kmalloc()
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*
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* This macro dynamically allocates a new fifo buffer.
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*
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* The number of elements will be rounded-up to a power of 2.
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* The fifo will be release with kfifo_free().
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* Return 0 if no error, otherwise an error code.
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*/
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#define kfifo_alloc(fifo, size, gfp_mask) \
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__kfifo_int_must_check_helper( \
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({ \
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typeof((fifo) + 1) __tmp = (fifo); \
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struct __kfifo *__kfifo = &__tmp->kfifo; \
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__is_kfifo_ptr(__tmp) ? \
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__kfifo_alloc(__kfifo, size, sizeof(*__tmp->type), gfp_mask) : \
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-EINVAL; \
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}) \
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)
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/**
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* kfifo_free - frees the fifo
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* @fifo: the fifo to be freed
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*/
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#define kfifo_free(fifo) \
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({ \
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typeof((fifo) + 1) __tmp = (fifo); \
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struct __kfifo *__kfifo = &__tmp->kfifo; \
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if (__is_kfifo_ptr(__tmp)) \
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__kfifo_free(__kfifo); \
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})
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/**
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* kfifo_init - initialize a fifo using a preallocated buffer
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* @fifo: the fifo to assign the buffer
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* @buffer: the preallocated buffer to be used
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* @size: the size of the internal buffer, this have to be a power of 2
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*
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* This macro initializes a fifo using a preallocated buffer.
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*
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* The number of elements will be rounded-up to a power of 2.
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* Return 0 if no error, otherwise an error code.
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*/
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#define kfifo_init(fifo, buffer, size) \
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({ \
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typeof((fifo) + 1) __tmp = (fifo); \
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struct __kfifo *__kfifo = &__tmp->kfifo; \
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__is_kfifo_ptr(__tmp) ? \
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__kfifo_init(__kfifo, buffer, size, sizeof(*__tmp->type)) : \
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-EINVAL; \
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})
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/**
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* kfifo_put - put data into the fifo
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* @fifo: address of the fifo to be used
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* @val: the data to be added
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*
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* This macro copies the given value into the fifo.
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* It returns 0 if the fifo was full. Otherwise it returns the number
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* processed elements.
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*
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* Note that with only one concurrent reader and one concurrent
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* writer, you don't need extra locking to use these macro.
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*/
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#define kfifo_put(fifo, val) \
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({ \
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typeof((fifo) + 1) __tmp = (fifo); \
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typeof(*__tmp->const_type) __val = (val); \
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unsigned int __ret; \
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size_t __recsize = sizeof(*__tmp->rectype); \
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struct __kfifo *__kfifo = &__tmp->kfifo; \
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if (__recsize) \
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__ret = __kfifo_in_r(__kfifo, &__val, sizeof(__val), \
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__recsize); \
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else { \
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__ret = !kfifo_is_full(__tmp); \
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if (__ret) { \
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(__is_kfifo_ptr(__tmp) ? \
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((typeof(__tmp->type))__kfifo->data) : \
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(__tmp->buf) \
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)[__kfifo->in & __tmp->kfifo.mask] = \
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*(typeof(__tmp->type))&__val; \
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smp_wmb(); \
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__kfifo->in++; \
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} \
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} \
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__ret; \
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})
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/**
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* kfifo_get - get data from the fifo
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* @fifo: address of the fifo to be used
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* @val: address where to store the data
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*
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* This macro reads the data from the fifo.
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* It returns 0 if the fifo was empty. Otherwise it returns the number
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* processed elements.
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*
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* Note that with only one concurrent reader and one concurrent
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* writer, you don't need extra locking to use these macro.
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*/
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#define kfifo_get(fifo, val) \
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__kfifo_uint_must_check_helper( \
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({ \
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typeof((fifo) + 1) __tmp = (fifo); \
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typeof(__tmp->ptr) __val = (val); \
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unsigned int __ret; \
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const size_t __recsize = sizeof(*__tmp->rectype); \
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struct __kfifo *__kfifo = &__tmp->kfifo; \
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if (__recsize) \
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__ret = __kfifo_out_r(__kfifo, __val, sizeof(*__val), \
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__recsize); \
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else { \
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__ret = !kfifo_is_empty(__tmp); \
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if (__ret) { \
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*(typeof(__tmp->type))__val = \
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(__is_kfifo_ptr(__tmp) ? \
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((typeof(__tmp->type))__kfifo->data) : \
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(__tmp->buf) \
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)[__kfifo->out & __tmp->kfifo.mask]; \
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smp_wmb(); \
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__kfifo->out++; \
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} \
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} \
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__ret; \
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}) \
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)
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/**
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* kfifo_peek - get data from the fifo without removing
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* @fifo: address of the fifo to be used
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* @val: address where to store the data
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*
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* This reads the data from the fifo without removing it from the fifo.
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* It returns 0 if the fifo was empty. Otherwise it returns the number
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* processed elements.
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*
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* Note that with only one concurrent reader and one concurrent
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* writer, you don't need extra locking to use these macro.
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*/
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#define kfifo_peek(fifo, val) \
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__kfifo_uint_must_check_helper( \
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({ \
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typeof((fifo) + 1) __tmp = (fifo); \
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typeof(__tmp->ptr) __val = (val); \
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unsigned int __ret; \
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const size_t __recsize = sizeof(*__tmp->rectype); \
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struct __kfifo *__kfifo = &__tmp->kfifo; \
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if (__recsize) \
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__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(__tmp->ptr_const) __buf = (buf); \
|
|
unsigned long __n = (n); \
|
|
const size_t __recsize = sizeof(*__tmp->rectype); \
|
|
struct __kfifo *__kfifo = &__tmp->kfifo; \
|
|
(__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_uint_must_check_helper( \
|
|
({ \
|
|
typeof((fifo) + 1) __tmp = (fifo); \
|
|
typeof(__tmp->ptr) __buf = (buf); \
|
|
unsigned long __n = (n); \
|
|
const size_t __recsize = sizeof(*__tmp->rectype); \
|
|
struct __kfifo *__kfifo = &__tmp->kfifo; \
|
|
(__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_uint_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_uint_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_uint_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 transferred
|
|
*
|
|
* 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_uint_must_check_helper( \
|
|
({ \
|
|
typeof((fifo) + 1) __tmp = (fifo); \
|
|
typeof(__tmp->ptr) __buf = (buf); \
|
|
unsigned long __n = (n); \
|
|
const size_t __recsize = sizeof(*__tmp->rectype); \
|
|
struct __kfifo *__kfifo = &__tmp->kfifo; \
|
|
(__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 void __kfifo_skip_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
|