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/*
* This file is part of the coreboot project.
*
* Copyright 2015 Google Inc.
*
* 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; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc.
*/
#include <region.h>
#include <string.h>
static inline size_t region_offset(const struct region *r)
{
return r->offset;
}
static inline size_t region_end(const struct region *r)
{
return region_sz(r) + region_offset(r);
}
static int is_subregion(const struct region *p, const struct region *c)
{
if (region_offset(c) < region_offset(p))
return 0;
if (region_sz(c) > region_sz(p))
return 0;
if (region_end(c) > region_end(p))
return 0;
return 1;
}
static int normalize_and_ok(const struct region *outer, struct region *inner)
{
inner->offset += region_offset(outer);
return is_subregion(outer, inner);
}
static const struct region_device *rdev_root(const struct region_device *rdev)
{
if (rdev->root == NULL)
return rdev;
return rdev->root;
}
void *rdev_mmap(const struct region_device *rd, size_t offset, size_t size)
{
const struct region_device *rdev;
struct region req = {
.offset = offset,
.size = size,
};
if (!normalize_and_ok(&rd->region, &req))
return NULL;
rdev = rdev_root(rd);
return rdev->ops->mmap(rdev, req.offset, req.size);
}
int rdev_munmap(const struct region_device *rd, void *mapping)
{
const struct region_device *rdev;
rdev = rdev_root(rd);
return rdev->ops->munmap(rdev, mapping);
}
ssize_t rdev_readat(const struct region_device *rd, void *b, size_t offset,
size_t size)
{
const struct region_device *rdev;
struct region req = {
.offset = offset,
.size = size,
};
if (!normalize_and_ok(&rd->region, &req))
return -1;
rdev = rdev_root(rd);
return rdev->ops->readat(rdev, b, req.offset, req.size);
}
int rdev_chain(struct region_device *child, const struct region_device *parent,
size_t offset, size_t size)
{
struct region req = {
.offset = offset,
.size = size,
};
if (!normalize_and_ok(&parent->region, &req))
return -1;
/* Keep track of root region device. Note the offsets are relative
* to the root device. */
child->root = rdev_root(parent);
child->ops = NULL;
child->region.offset = req.offset;
child->region.size = req.size;
return 0;
}
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