Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  * A generic kernel FIFO implementation
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  * Copyright (C) 2009/2010 Stefani Seibold <stefani@seibold.net>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) #include <linux/export.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) #include <linux/err.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include <linux/log2.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include <linux/uaccess.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) #include <linux/kfifo.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17)  * internal helper to calculate the unused elements in a fifo
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) static inline unsigned int kfifo_unused(struct __kfifo *fifo)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) 	return (fifo->mask + 1) - (fifo->in - fifo->out);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) int __kfifo_alloc(struct __kfifo *fifo, unsigned int size,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) 		size_t esize, gfp_t gfp_mask)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) 	 * round up to the next power of 2, since our 'let the indices
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) 	 * wrap' technique works only in this case.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 	size = roundup_pow_of_two(size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 	fifo->in = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 	fifo->out = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 	fifo->esize = esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 	if (size < 2) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 		fifo->data = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 		fifo->mask = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	fifo->data = kmalloc_array(esize, size, gfp_mask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 	if (!fifo->data) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 		fifo->mask = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 	fifo->mask = size - 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) EXPORT_SYMBOL(__kfifo_alloc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) void __kfifo_free(struct __kfifo *fifo)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 	kfree(fifo->data);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 	fifo->in = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 	fifo->out = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 	fifo->esize = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 	fifo->data = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 	fifo->mask = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) EXPORT_SYMBOL(__kfifo_free);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) int __kfifo_init(struct __kfifo *fifo, void *buffer,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 		unsigned int size, size_t esize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) 	size /= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 	if (!is_power_of_2(size))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 		size = rounddown_pow_of_two(size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 	fifo->in = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 	fifo->out = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 	fifo->esize = esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 	fifo->data = buffer;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 	if (size < 2) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 		fifo->mask = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 	fifo->mask = size - 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) EXPORT_SYMBOL(__kfifo_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) static void kfifo_copy_in(struct __kfifo *fifo, const void *src,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 		unsigned int len, unsigned int off)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 	unsigned int size = fifo->mask + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 	unsigned int esize = fifo->esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 	unsigned int l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 	off &= fifo->mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 	if (esize != 1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 		off *= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 		size *= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 		len *= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 	l = min(len, size - off);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 	memcpy(fifo->data + off, src, l);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 	memcpy(fifo->data, src + l, len - l);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 	 * make sure that the data in the fifo is up to date before
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 	 * incrementing the fifo->in index counter
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 	smp_wmb();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) unsigned int __kfifo_in(struct __kfifo *fifo,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 		const void *buf, unsigned int len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 	unsigned int l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 	l = kfifo_unused(fifo);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 	if (len > l)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 		len = l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 	kfifo_copy_in(fifo, buf, len, fifo->in);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 	fifo->in += len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 	return len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) EXPORT_SYMBOL(__kfifo_in);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) static void kfifo_copy_out(struct __kfifo *fifo, void *dst,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 		unsigned int len, unsigned int off)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 	unsigned int size = fifo->mask + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 	unsigned int esize = fifo->esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 	unsigned int l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 	off &= fifo->mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 	if (esize != 1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 		off *= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 		size *= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 		len *= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 	l = min(len, size - off);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 	memcpy(dst, fifo->data + off, l);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 	memcpy(dst + l, fifo->data, len - l);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 	 * make sure that the data is copied before
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 	 * incrementing the fifo->out index counter
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 	smp_wmb();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) unsigned int __kfifo_out_peek(struct __kfifo *fifo,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 		void *buf, unsigned int len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 	unsigned int l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 	l = fifo->in - fifo->out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 	if (len > l)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 		len = l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 	kfifo_copy_out(fifo, buf, len, fifo->out);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 	return len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) EXPORT_SYMBOL(__kfifo_out_peek);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) unsigned int __kfifo_out(struct __kfifo *fifo,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 		void *buf, unsigned int len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 	len = __kfifo_out_peek(fifo, buf, len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 	fifo->out += len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 	return len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) EXPORT_SYMBOL(__kfifo_out);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) static unsigned long kfifo_copy_from_user(struct __kfifo *fifo,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 	const void __user *from, unsigned int len, unsigned int off,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 	unsigned int *copied)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 	unsigned int size = fifo->mask + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 	unsigned int esize = fifo->esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 	unsigned int l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 	unsigned long ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 	off &= fifo->mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 	if (esize != 1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 		off *= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 		size *= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 		len *= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 	l = min(len, size - off);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 	ret = copy_from_user(fifo->data + off, from, l);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 	if (unlikely(ret))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) 		ret = DIV_ROUND_UP(ret + len - l, esize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) 	else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) 		ret = copy_from_user(fifo->data, from + l, len - l);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) 		if (unlikely(ret))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) 			ret = DIV_ROUND_UP(ret, esize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) 	 * make sure that the data in the fifo is up to date before
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) 	 * incrementing the fifo->in index counter
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) 	smp_wmb();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) 	*copied = len - ret * esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) 	/* return the number of elements which are not copied */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) int __kfifo_from_user(struct __kfifo *fifo, const void __user *from,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) 		unsigned long len, unsigned int *copied)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) 	unsigned int l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) 	unsigned long ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) 	unsigned int esize = fifo->esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) 	int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) 	if (esize != 1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) 		len /= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) 	l = kfifo_unused(fifo);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) 	if (len > l)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) 		len = l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) 	ret = kfifo_copy_from_user(fifo, from, len, fifo->in, copied);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) 	if (unlikely(ret)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) 		len -= ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) 		err = -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) 	} else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) 		err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) 	fifo->in += len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) 	return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) EXPORT_SYMBOL(__kfifo_from_user);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) static unsigned long kfifo_copy_to_user(struct __kfifo *fifo, void __user *to,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) 		unsigned int len, unsigned int off, unsigned int *copied)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) 	unsigned int l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) 	unsigned long ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) 	unsigned int size = fifo->mask + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) 	unsigned int esize = fifo->esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) 	off &= fifo->mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) 	if (esize != 1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) 		off *= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) 		size *= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) 		len *= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) 	l = min(len, size - off);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) 	ret = copy_to_user(to, fifo->data + off, l);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) 	if (unlikely(ret))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) 		ret = DIV_ROUND_UP(ret + len - l, esize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) 	else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) 		ret = copy_to_user(to + l, fifo->data, len - l);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) 		if (unlikely(ret))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) 			ret = DIV_ROUND_UP(ret, esize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) 	 * make sure that the data is copied before
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) 	 * incrementing the fifo->out index counter
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) 	smp_wmb();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) 	*copied = len - ret * esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) 	/* return the number of elements which are not copied */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) int __kfifo_to_user(struct __kfifo *fifo, void __user *to,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) 		unsigned long len, unsigned int *copied)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) 	unsigned int l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) 	unsigned long ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) 	unsigned int esize = fifo->esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) 	int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) 	if (esize != 1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) 		len /= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) 	l = fifo->in - fifo->out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) 	if (len > l)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) 		len = l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) 	ret = kfifo_copy_to_user(fifo, to, len, fifo->out, copied);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) 	if (unlikely(ret)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) 		len -= ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) 		err = -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) 	} else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) 		err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) 	fifo->out += len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) 	return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) EXPORT_SYMBOL(__kfifo_to_user);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) static int setup_sgl_buf(struct scatterlist *sgl, void *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) 		int nents, unsigned int len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) 	int n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) 	unsigned int l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) 	unsigned int off;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) 	struct page *page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) 	if (!nents)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) 	if (!len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) 	n = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) 	page = virt_to_page(buf);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) 	off = offset_in_page(buf);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) 	l = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) 	while (len >= l + PAGE_SIZE - off) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) 		struct page *npage;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) 		l += PAGE_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) 		buf += PAGE_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) 		npage = virt_to_page(buf);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) 		if (page_to_phys(page) != page_to_phys(npage) - l) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) 			sg_set_page(sgl, page, l - off, off);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) 			sgl = sg_next(sgl);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) 			if (++n == nents || sgl == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) 				return n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) 			page = npage;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) 			len -= l - off;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) 			l = off = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) 	sg_set_page(sgl, page, len, off);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) 	return n + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) static unsigned int setup_sgl(struct __kfifo *fifo, struct scatterlist *sgl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) 		int nents, unsigned int len, unsigned int off)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) 	unsigned int size = fifo->mask + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) 	unsigned int esize = fifo->esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) 	unsigned int l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) 	unsigned int n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) 	off &= fifo->mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) 	if (esize != 1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) 		off *= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) 		size *= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) 		len *= esize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) 	l = min(len, size - off);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) 	n = setup_sgl_buf(sgl, fifo->data + off, nents, l);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) 	n += setup_sgl_buf(sgl + n, fifo->data, nents - n, len - l);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) 	return n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) unsigned int __kfifo_dma_in_prepare(struct __kfifo *fifo,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) 		struct scatterlist *sgl, int nents, unsigned int len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) 	unsigned int l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) 	l = kfifo_unused(fifo);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) 	if (len > l)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) 		len = l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) 	return setup_sgl(fifo, sgl, nents, len, fifo->in);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) EXPORT_SYMBOL(__kfifo_dma_in_prepare);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) unsigned int __kfifo_dma_out_prepare(struct __kfifo *fifo,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) 		struct scatterlist *sgl, int nents, unsigned int len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) 	unsigned int l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) 	l = fifo->in - fifo->out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) 	if (len > l)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) 		len = l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) 	return setup_sgl(fifo, sgl, nents, len, fifo->out);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) EXPORT_SYMBOL(__kfifo_dma_out_prepare);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) unsigned int __kfifo_max_r(unsigned int len, size_t recsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) 	unsigned int max = (1 << (recsize << 3)) - 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) 	if (len > max)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) 		return max;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) 	return len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) EXPORT_SYMBOL(__kfifo_max_r);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) #define	__KFIFO_PEEK(data, out, mask) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) 	((data)[(out) & (mask)])
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395)  * __kfifo_peek_n internal helper function for determinate the length of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396)  * the next record in the fifo
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) static unsigned int __kfifo_peek_n(struct __kfifo *fifo, size_t recsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) 	unsigned int l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) 	unsigned int mask = fifo->mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) 	unsigned char *data = fifo->data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) 	l = __KFIFO_PEEK(data, fifo->out, mask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) 	if (--recsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) 		l |= __KFIFO_PEEK(data, fifo->out + 1, mask) << 8;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) 	return l;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412) #define	__KFIFO_POKE(data, in, mask, val) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) 	( \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414) 	(data)[(in) & (mask)] = (unsigned char)(val) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) 	)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418)  * __kfifo_poke_n internal helper function for storeing the length of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419)  * the record into the fifo
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) static void __kfifo_poke_n(struct __kfifo *fifo, unsigned int n, size_t recsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) 	unsigned int mask = fifo->mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) 	unsigned char *data = fifo->data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) 	__KFIFO_POKE(data, fifo->in, mask, n);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) 	if (recsize > 1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429) 		__KFIFO_POKE(data, fifo->in + 1, mask, n >> 8);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432) unsigned int __kfifo_len_r(struct __kfifo *fifo, size_t recsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) 	return __kfifo_peek_n(fifo, recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) EXPORT_SYMBOL(__kfifo_len_r);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438) unsigned int __kfifo_in_r(struct __kfifo *fifo, const void *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) 		unsigned int len, size_t recsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) 	if (len + recsize > kfifo_unused(fifo))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) 	__kfifo_poke_n(fifo, len, recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446) 	kfifo_copy_in(fifo, buf, len, fifo->in + recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447) 	fifo->in += len + recsize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) 	return len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) EXPORT_SYMBOL(__kfifo_in_r);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452) static unsigned int kfifo_out_copy_r(struct __kfifo *fifo,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) 	void *buf, unsigned int len, size_t recsize, unsigned int *n)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455) 	*n = __kfifo_peek_n(fifo, recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) 	if (len > *n)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458) 		len = *n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) 	kfifo_copy_out(fifo, buf, len, fifo->out + recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461) 	return len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464) unsigned int __kfifo_out_peek_r(struct __kfifo *fifo, void *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465) 		unsigned int len, size_t recsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467) 	unsigned int n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469) 	if (fifo->in == fifo->out)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472) 	return kfifo_out_copy_r(fifo, buf, len, recsize, &n);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474) EXPORT_SYMBOL(__kfifo_out_peek_r);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) unsigned int __kfifo_out_r(struct __kfifo *fifo, void *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477) 		unsigned int len, size_t recsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479) 	unsigned int n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481) 	if (fifo->in == fifo->out)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484) 	len = kfifo_out_copy_r(fifo, buf, len, recsize, &n);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485) 	fifo->out += n + recsize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486) 	return len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488) EXPORT_SYMBOL(__kfifo_out_r);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) void __kfifo_skip_r(struct __kfifo *fifo, size_t recsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) 	unsigned int n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) 	n = __kfifo_peek_n(fifo, recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495) 	fifo->out += n + recsize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) EXPORT_SYMBOL(__kfifo_skip_r);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499) int __kfifo_from_user_r(struct __kfifo *fifo, const void __user *from,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500) 	unsigned long len, unsigned int *copied, size_t recsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502) 	unsigned long ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504) 	len = __kfifo_max_r(len, recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506) 	if (len + recsize > kfifo_unused(fifo)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507) 		*copied = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) 	__kfifo_poke_n(fifo, len, recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) 	ret = kfifo_copy_from_user(fifo, from, len, fifo->in + recsize, copied);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) 	if (unlikely(ret)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) 		*copied = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516) 		return -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) 	fifo->in += len + recsize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) EXPORT_SYMBOL(__kfifo_from_user_r);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523) int __kfifo_to_user_r(struct __kfifo *fifo, void __user *to,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524) 	unsigned long len, unsigned int *copied, size_t recsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526) 	unsigned long ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527) 	unsigned int n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) 	if (fifo->in == fifo->out) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530) 		*copied = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534) 	n = __kfifo_peek_n(fifo, recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535) 	if (len > n)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536) 		len = n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538) 	ret = kfifo_copy_to_user(fifo, to, len, fifo->out + recsize, copied);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539) 	if (unlikely(ret)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540) 		*copied = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541) 		return -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 543) 	fifo->out += n + recsize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 544) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 545) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 546) EXPORT_SYMBOL(__kfifo_to_user_r);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 547) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 548) unsigned int __kfifo_dma_in_prepare_r(struct __kfifo *fifo,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 549) 	struct scatterlist *sgl, int nents, unsigned int len, size_t recsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 550) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 551) 	BUG_ON(!nents);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 552) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 553) 	len = __kfifo_max_r(len, recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 554) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 555) 	if (len + recsize > kfifo_unused(fifo))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 556) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 557) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 558) 	return setup_sgl(fifo, sgl, nents, len, fifo->in + recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 559) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 560) EXPORT_SYMBOL(__kfifo_dma_in_prepare_r);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 561) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 562) void __kfifo_dma_in_finish_r(struct __kfifo *fifo,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 563) 	unsigned int len, size_t recsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 564) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 565) 	len = __kfifo_max_r(len, recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 566) 	__kfifo_poke_n(fifo, len, recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 567) 	fifo->in += len + recsize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 568) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 569) EXPORT_SYMBOL(__kfifo_dma_in_finish_r);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 570) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 571) unsigned int __kfifo_dma_out_prepare_r(struct __kfifo *fifo,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 572) 	struct scatterlist *sgl, int nents, unsigned int len, size_t recsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 573) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 574) 	BUG_ON(!nents);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 575) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 576) 	len = __kfifo_max_r(len, recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 577) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 578) 	if (len + recsize > fifo->in - fifo->out)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 579) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 580) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 581) 	return setup_sgl(fifo, sgl, nents, len, fifo->out + recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 582) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 583) EXPORT_SYMBOL(__kfifo_dma_out_prepare_r);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 584) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 585) void __kfifo_dma_out_finish_r(struct __kfifo *fifo, size_t recsize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 586) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 587) 	unsigned int len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 588) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 589) 	len = __kfifo_peek_n(fifo, recsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 590) 	fifo->out += len + recsize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 591) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 592) EXPORT_SYMBOL(__kfifo_dma_out_finish_r);