/* * Cryptographic API. * * Cipher operations. * * Copyright (c) 2002 James Morris <jmorris@intercode.com.au> * 2002 Adam J. Richter <adam@yggdrasil.com> * 2004 Jean-Luc Cooke <jlcooke@certainkey.com> * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the Free * Software Foundation; either version 2 of the License, or (at your option) * any later version. * */ #include <linux/kernel.h> #include <linux/mm.h> #include <linux/module.h> #include <linux/pagemap.h> #include <linux/highmem.h> #include <linux/scatterlist.h> #include "internal.h" #include "scatterwalk.h" enum km_type crypto_km_types[] = { KM_USER0, KM_USER1, KM_SOFTIRQ0, KM_SOFTIRQ1, }; EXPORT_SYMBOL_GPL(crypto_km_types); static inline void memcpy_dir(void *buf, void *sgdata, size_t nbytes, int out) { void *src = out ? buf : sgdata; void *dst = out ? sgdata : buf; memcpy(dst, src, nbytes); } void scatterwalk_start(struct scatter_walk *walk, struct scatterlist *sg) { walk->sg = sg; BUG_ON(!sg->length); walk->offset = sg->offset; } EXPORT_SYMBOL_GPL(scatterwalk_start); void *scatterwalk_map(struct scatter_walk *walk, int out) { return crypto_kmap(scatterwalk_page(walk), out) + offset_in_page(walk->offset); } EXPORT_SYMBOL_GPL(scatterwalk_map); static void scatterwalk_pagedone(struct scatter_walk *walk, int out, unsigned int more) { if (out) { struct page *page; page = walk->sg->page + ((walk->offset - 1) >> PAGE_SHIFT); flush_dcache_page(page); } if (more) { walk->offset += PAGE_SIZE - 1; walk->offset &= PAGE_MASK; if (walk->offset >= walk->sg->offset + walk->sg->length) scatterwalk_start(walk, sg_next(walk->sg)); } } void scatterwalk_done(struct scatter_walk *walk, int out, int more) { if (!offset_in_page(walk->offset) || !more) scatterwalk_pagedone(walk, out, more); } EXPORT_SYMBOL_GPL(scatterwalk_done); void scatterwalk_copychunks(void *buf, struct scatter_walk *walk, size_t nbytes, int out) { for (;;) { unsigned int len_this_page = scatterwalk_pagelen(walk); u8 *vaddr; if (len_this_page > nbytes) len_this_page = nbytes; vaddr = scatterwalk_map(walk, out); memcpy_dir(buf, vaddr, len_this_page, out); scatterwalk_unmap(vaddr, out); scatterwalk_advance(walk, len_this_page); if (nbytes == len_this_page) break; buf += len_this_page; nbytes -= len_this_page; scatterwalk_pagedone(walk, out, 1); } } EXPORT_SYMBOL_GPL(scatterwalk_copychunks);