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/* SPDX-License-Identifier: GPL-2.0-only */
#include <console/console.h>
#include <commonlib/region.h>
#include <cpu/x86/smm.h>
#include <smmstore.h>
#include <stddef.h>
#include <stdint.h>
/*
* Check that the given range is legal.
*
* Legal means:
* - not pointing into SMRAM
*
* returns 0 on success, -1 on failure
*/
static int range_check(void *start, size_t size)
{
if (smm_points_to_smram(start, size))
return -1;
return 0;
}
/* Param is usually EBX, ret in EAX */
uint32_t smmstore_exec(uint8_t command, void *param)
{
uint32_t ret = SMMSTORE_RET_FAILURE;
switch (command) {
case SMMSTORE_CMD_READ: {
printk(BIOS_DEBUG, "Reading from SMM store\n");
struct smmstore_params_read *params = param;
if (range_check(params, sizeof(*params)) != 0)
break;
if (range_check(params->buf, params->bufsize) != 0)
break;
if (smmstore_read_region(params->buf, ¶ms->bufsize) == 0)
ret = SMMSTORE_RET_SUCCESS;
break;
}
case SMMSTORE_CMD_APPEND: {
printk(BIOS_DEBUG, "Appending into SMM store\n");
struct smmstore_params_append *params = param;
if (range_check(params, sizeof(*params)) != 0)
break;
if (range_check(params->key, params->keysize) != 0)
break;
if (range_check(params->val, params->valsize) != 0)
break;
if (smmstore_append_data(params->key, params->keysize,
params->val, params->valsize) == 0)
ret = SMMSTORE_RET_SUCCESS;
break;
}
case SMMSTORE_CMD_CLEAR: {
if (smmstore_clear_region() == 0)
ret = SMMSTORE_RET_SUCCESS;
break;
}
default:
printk(BIOS_DEBUG,
"Unknown SMM store command: 0x%02x\n", command);
ret = SMMSTORE_RET_UNSUPPORTED;
break;
}
return ret;
}
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