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/*
* Copyright (c) 2019 Amazon.com, Inc. or its affiliates. All rights reserved.
*
*/
#include "config.h"
#include <xen/lib.h>
#include <xen/types.h>
#include <xen/version.h>
#include <xen/livepatch.h>
#include <xen/livepatch_payload.h>
#include <public/sysctl.h>
static const char hello_world_patch_this_fnc[] = "xen_extra_version";
extern const char *xen_hello_world(void);
static unsigned int apply_cnt;
static unsigned int revert_cnt;
static int apply_hook(livepatch_payload_t *payload)
{
int i;
printk(KERN_DEBUG "%s: Hook starting.\n", __func__);
for (i = 0; i < payload->nfuncs; i++)
{
struct livepatch_func *func = &payload->funcs[i];
func->applied = LIVEPATCH_FUNC_APPLIED;
apply_cnt++;
printk(KERN_DEBUG "%s: applying: %s\n", __func__, func->name);
}
printk(KERN_DEBUG "%s: Hook done.\n", __func__);
return 0;
}
static int revert_hook(livepatch_payload_t *payload)
{
int i;
printk(KERN_DEBUG "%s: Hook starting.\n", __func__);
for (i = 0; i < payload->nfuncs; i++)
{
struct livepatch_func *func = &payload->funcs[i];
func->applied = LIVEPATCH_FUNC_NOT_APPLIED;
revert_cnt++;
printk(KERN_DEBUG "%s: reverting: %s\n", __func__, func->name);
}
printk(KERN_DEBUG "%s: Hook done.\n", __func__);
return 0;
}
static void post_revert_hook(livepatch_payload_t *payload)
{
int i;
printk(KERN_DEBUG "%s: Hook starting.\n", __func__);
for (i = 0; i < payload->nfuncs; i++)
{
struct livepatch_func *func = &payload->funcs[i];
printk(KERN_DEBUG "%s: reverted: %s\n", __func__, func->name);
}
BUG_ON(apply_cnt != 1 || revert_cnt != 1);
printk(KERN_DEBUG "%s: Hook done.\n", __func__);
}
LIVEPATCH_APPLY_HOOK(apply_hook);
LIVEPATCH_REVERT_HOOK(revert_hook);
LIVEPATCH_POSTREVERT_HOOK(post_revert_hook);
struct livepatch_func __section(".livepatch.funcs") livepatch_xen_hello_world = {
.version = LIVEPATCH_PAYLOAD_VERSION,
.name = hello_world_patch_this_fnc,
.new_addr = xen_hello_world,
.old_addr = xen_extra_version,
.new_size = NEW_CODE_SZ,
.old_size = OLD_CODE_SZ,
};
/*
* Local variables:
* mode: C
* c-file-style: "BSD"
* c-basic-offset: 4
* tab-width: 4
* indent-tabs-mode: nil
* End:
*/
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