/****************************************************************************
* binfmt/libelf/libelf_addrenv.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/addrenv.h>
#include <nuttx/arch.h>
#include <nuttx/kmalloc.h>
#include <sys/mman.h>
#include "libelf.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define ELF_TEXT_WRE (PROT_READ | PROT_WRITE | PROT_EXEC)
#define ELF_TEXT_WRD (PROT_READ | PROT_EXEC)
/****************************************************************************
* Private Constant Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: elf_addrenv_alloc
*
* Description:
* Allocate memory for the ELF image (textalloc and dataalloc). If
* CONFIG_ARCH_ADDRENV=n, textalloc will be allocated using kmm_zalloc()
* and dataalloc will be a offset from textalloc. If
* CONFIG_ARCH_ADDRENV=y, then textalloc and dataalloc will be allocated
* using up_addrenv_create(). In either case, there will be a unique
* instance of textalloc and dataalloc (and stack) for each instance of a
* process.
*
* Input Parameters:
* loadinfo - Load state information
* textsize - The size (in bytes) of the .text address environment needed
* for the ELF image (read/execute).
* datasize - The size (in bytes) of the .bss/.data address environment
* needed for the ELF image (read/write).
* heapsize - The initial size (in bytes) of the heap address environment
* needed by the task. This region may be read/write only.
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure.
*
****************************************************************************/
int elf_addrenv_alloc(FAR struct elf_loadinfo_s *loadinfo, size_t textsize,
size_t datasize, size_t heapsize)
{
#ifdef CONFIG_ARCH_ADDRENV
FAR struct arch_addrenv_s *addrenv;
FAR void *vtext;
FAR void *vdata;
int ret;
/* Create an address environment for the new ELF task */
loadinfo->addrenv = addrenv_allocate();
if (!loadinfo->addrenv)
{
return -ENOMEM;
}
/* Start creating the address environment sections */
addrenv = &loadinfo->addrenv->addrenv;
ret = up_addrenv_create(textsize, datasize, heapsize, addrenv);
if (ret < 0)
{
berr("ERROR: up_addrenv_create failed: %d\n", ret);
goto errout_with_addrenv;
}
/* Get the virtual address associated with the start of the address
* environment. This is the base address that we will need to use to
* access the ELF image (but only if the address environment has been
* selected.
*/
ret = up_addrenv_vtext(addrenv, &vtext);
if (ret < 0)
{
berr("ERROR: up_addrenv_vtext failed: %d\n", ret);
goto errout_with_addrenv;
}
ret = up_addrenv_vdata(addrenv, textsize, &vdata);
if (ret < 0)
{
berr("ERROR: up_addrenv_vdata failed: %d\n", ret);
goto errout_with_addrenv;
}
loadinfo->textalloc = (uintptr_t)vtext;
loadinfo->dataalloc = (uintptr_t)vdata;
return OK;
errout_with_addrenv:
addrenv_drop(loadinfo->addrenv, false);
return ret;
#else
if (loadinfo->ehdr.e_type == ET_EXEC)
{
return OK;
}
/* Allocate memory to hold the ELF image */
#if defined(CONFIG_ARCH_USE_TEXT_HEAP)
loadinfo->textalloc = (uintptr_t)
up_textheap_memalign(loadinfo->textalign,
textsize);
#else
loadinfo->textalloc = (uintptr_t)kumm_memalign(loadinfo->textalign,
textsize);
#endif
if (!loadinfo->textalloc)
{
return -ENOMEM;
}
if (loadinfo->datasize > 0)
{
loadinfo->dataalloc = (uintptr_t)kumm_memalign(loadinfo->dataalign,
datasize);
if (!loadinfo->dataalloc)
{
return -ENOMEM;
}
}
return OK;
#endif
}
/****************************************************************************
* Name: elf_addrenv_select
*
* Description:
* Temporarily select the task's address environment.
*
* Input Parameters:
* loadinfo - Load state information
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure.
*
****************************************************************************/
#ifdef CONFIG_ARCH_ADDRENV
int elf_addrenv_select(FAR struct elf_loadinfo_s *loadinfo)
{
int ret;
/* Instantiate the new address environment */
ret = addrenv_select(loadinfo->addrenv, &loadinfo->oldenv);
if (ret < 0)
{
berr("ERROR: addrenv_select failed: %d\n", ret);
return ret;
}
/* Allow write access to .text */
ret = up_addrenv_mprot(&loadinfo->addrenv->addrenv, loadinfo->textalloc,
loadinfo->textsize, ELF_TEXT_WRE);
if (ret < 0)
{
berr("ERROR: up_addrenv_text_enable_write failed: %d\n", ret);
return ret;
}
return OK;
}
#endif
/****************************************************************************
* Name: elf_addrenv_restore
*
* Description:
* Restore the address environment before elf_addrenv_select() was called..
*
* Input Parameters:
* loadinfo - Load state information
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure.
*
****************************************************************************/
#ifdef CONFIG_ARCH_ADDRENV
int elf_addrenv_restore(FAR struct elf_loadinfo_s *loadinfo)
{
int ret;
/* Remove write access to .text */
ret = up_addrenv_mprot(&loadinfo->addrenv->addrenv, loadinfo->textalloc,
loadinfo->textsize, ELF_TEXT_WRD);
if (ret < 0)
{
berr("ERROR: up_addrenv_text_disable_write failed: %d\n", ret);
return ret;
}
/* Restore the old address environment */
ret = addrenv_restore(loadinfo->oldenv);
if (ret < 0)
{
berr("ERROR: addrenv_restore failed: %d\n", ret);
return ret;
}
return OK;
}
#endif
/****************************************************************************
* Name: elf_addrenv_free
*
* Description:
* Release the address environment previously created by
* elf_addrenv_alloc(). This function is called only under certain error
* conditions after the module has been loaded but not yet started.
* After the module has been started, the address environment will
* automatically be freed when the module exits.
*
* Input Parameters:
* loadinfo - Load state information
*
* Returned Value:
* None.
*
****************************************************************************/
void elf_addrenv_free(FAR struct elf_loadinfo_s *loadinfo)
{
#ifdef CONFIG_ARCH_ADDRENV
/* Free the address environment */
addrenv_drop(loadinfo->addrenv, false);
#else
if (loadinfo->textalloc != 0)
{
#if defined(CONFIG_ARCH_USE_TEXT_HEAP)
up_textheap_free((FAR void *)loadinfo->textalloc);
#else
kumm_free((FAR void *)loadinfo->textalloc);
#endif
}
if (loadinfo->dataalloc != 0)
{
kumm_free((FAR void *)loadinfo->dataalloc);
}
#endif
/* Clear out all indications of the allocated address environment */
loadinfo->textalloc = 0;
loadinfo->dataalloc = 0;
loadinfo->textsize = 0;
loadinfo->datasize = 0;
}