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)  * Cryptographic API.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * Cipher operations.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7)  * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8)  *               2002 Adam J. Richter <adam@yggdrasil.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9)  *               2004 Jean-Luc Cooke <jlcooke@certainkey.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <crypto/scatterwalk.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/mm.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/scatterlist.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) static inline void memcpy_dir(void *buf, void *sgdata, size_t nbytes, int out)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 	void *src = out ? buf : sgdata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 	void *dst = out ? sgdata : buf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 	memcpy(dst, src, nbytes);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) void scatterwalk_copychunks(void *buf, struct scatter_walk *walk,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 			    size_t nbytes, int out)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 	for (;;) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 		unsigned int len_this_page = scatterwalk_pagelen(walk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 		u8 *vaddr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 		if (len_this_page > nbytes)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 			len_this_page = nbytes;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 		if (out != 2) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 			vaddr = scatterwalk_map(walk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 			memcpy_dir(buf, vaddr, len_this_page, out);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 			scatterwalk_unmap(vaddr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 		scatterwalk_advance(walk, len_this_page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 		if (nbytes == len_this_page)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 		buf += len_this_page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 		nbytes -= len_this_page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 		scatterwalk_pagedone(walk, out & 1, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) EXPORT_SYMBOL_GPL(scatterwalk_copychunks);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 			      unsigned int start, unsigned int nbytes, int out)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 	struct scatter_walk walk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 	struct scatterlist tmp[2];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 	if (!nbytes)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 	sg = scatterwalk_ffwd(tmp, sg, start);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 	scatterwalk_start(&walk, sg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 	scatterwalk_copychunks(buf, &walk, nbytes, out);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 	scatterwalk_done(&walk, out, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) EXPORT_SYMBOL_GPL(scatterwalk_map_and_copy);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) struct scatterlist *scatterwalk_ffwd(struct scatterlist dst[2],
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 				     struct scatterlist *src,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 				     unsigned int len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) 	for (;;) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) 		if (!len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) 			return src;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) 		if (src->length > len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) 		len -= src->length;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) 		src = sg_next(src);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) 	sg_init_table(dst, 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) 	sg_set_page(dst, sg_page(src), src->length - len, src->offset + len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) 	scatterwalk_crypto_chain(dst, sg_next(src), 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) 	return dst;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) EXPORT_SYMBOL_GPL(scatterwalk_ffwd);