*/
#include <linux/kernel.h>
#include <linux/mm.h>
+#include <linux/module.h>
#include <linux/pagemap.h>
#include <linux/highmem.h>
-#include <asm/scatterlist.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,
-};
-
-static void memcpy_dir(void *buf, void *sgdata, size_t nbytes, int out)
+static inline void memcpy_dir(void *buf, void *sgdata, size_t nbytes, int out)
{
- if (out)
- memcpy(sgdata, buf, nbytes);
- else
- memcpy(buf, sgdata, nbytes);
+ void *src = out ? buf : sgdata;
+ void *dst = out ? sgdata : buf;
+
+ memcpy(dst, src, nbytes);
}
void scatterwalk_start(struct scatter_walk *walk, struct scatterlist *sg)
{
- unsigned int rest_of_page;
-
walk->sg = sg;
- walk->page = sg->page;
- walk->len_this_segment = sg->length;
-
BUG_ON(!sg->length);
- rest_of_page = PAGE_CACHE_SIZE - (sg->offset & (PAGE_CACHE_SIZE - 1));
- walk->len_this_page = min(sg->length, rest_of_page);
walk->offset = sg->offset;
}
+EXPORT_SYMBOL_GPL(scatterwalk_start);
-void scatterwalk_map(struct scatter_walk *walk, int out)
-{
- walk->data = crypto_kmap(walk->page, out) + walk->offset;
-}
-
-static inline void scatterwalk_unmap(struct scatter_walk *walk, int out)
+void *scatterwalk_map(struct scatter_walk *walk, int out)
{
- /* walk->data may be pointing the first byte of the next page;
- however, we know we transfered at least one byte. So,
- walk->data - 1 will be a virtual address in the mapped page. */
- crypto_kunmap(walk->data - 1, 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)
- flush_dcache_page(walk->page);
+ if (out) {
+ struct page *page;
+
+ page = walk->sg->page + ((walk->offset - 1) >> PAGE_SHIFT);
+ flush_dcache_page(page);
+ }
if (more) {
- walk->len_this_segment -= walk->len_this_page;
-
- if (walk->len_this_segment) {
- walk->page++;
- walk->len_this_page = min(walk->len_this_segment,
- (unsigned)PAGE_CACHE_SIZE);
- walk->offset = 0;
- }
- else
+ 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)
{
- scatterwalk_unmap(walk, out);
- if (walk->len_this_page == 0 || !more)
+ if (!offset_in_page(walk->offset) || !more)
scatterwalk_pagedone(walk, out, more);
}
+EXPORT_SYMBOL_GPL(scatterwalk_done);
-/*
- * Do not call this unless the total length of all of the fragments
- * has been verified as multiple of the block size.
- */
-int scatterwalk_copychunks(void *buf, struct scatter_walk *walk,
- size_t nbytes, int out)
+void scatterwalk_copychunks(void *buf, struct scatter_walk *walk,
+ size_t nbytes, int out)
{
- while (nbytes > walk->len_this_page) {
- memcpy_dir(buf, walk->data, walk->len_this_page, out);
- buf += walk->len_this_page;
- nbytes -= walk->len_this_page;
+ 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_unmap(walk, out);
scatterwalk_pagedone(walk, out, 1);
- scatterwalk_map(walk, out);
+ }
+}
+EXPORT_SYMBOL_GPL(scatterwalk_copychunks);
+
+void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg,
+ unsigned int start, unsigned int nbytes, int out)
+{
+ struct scatter_walk walk;
+ unsigned int offset = 0;
+
+ for (;;) {
+ scatterwalk_start(&walk, sg);
+
+ if (start < offset + sg->length)
+ break;
+
+ offset += sg->length;
+ sg = sg_next(sg);
}
- memcpy_dir(buf, walk->data, nbytes, out);
- return nbytes;
+ scatterwalk_advance(&walk, start - offset);
+ scatterwalk_copychunks(buf, &walk, nbytes, out);
+ scatterwalk_done(&walk, out, 0);
}
+EXPORT_SYMBOL_GPL(scatterwalk_map_and_copy);