300 lines
9.0 KiB
C
300 lines
9.0 KiB
C
/****************************************************************************
|
|
* sched/module/mod_bind.c
|
|
*
|
|
* Copyright (C) 2015 Gregory Nutt. All rights reserved.
|
|
* Author: Gregory Nutt <gnutt@nuttx.org>
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in
|
|
* the documentation and/or other materials provided with the
|
|
* distribution.
|
|
* 3. Neither the name NuttX nor the names of its contributors may be
|
|
* used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
|
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
|
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
|
|
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
|
|
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
|
|
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
|
|
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Included Files
|
|
****************************************************************************/
|
|
|
|
#include <nuttx/config.h>
|
|
|
|
#include <stdint.h>
|
|
#include <string.h>
|
|
#include <elf32.h>
|
|
#include <errno.h>
|
|
#include <assert.h>
|
|
#include <debug.h>
|
|
|
|
#include <nuttx/module.h>
|
|
#include <nuttx/binfmt/symtab.h>
|
|
|
|
#include "module.h"
|
|
|
|
/****************************************************************************
|
|
* Private Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: mod_readrel
|
|
*
|
|
* Description:
|
|
* Read the ELF32_Rel structure into memory.
|
|
*
|
|
****************************************************************************/
|
|
|
|
static inline int mod_readrel(FAR struct mod_loadinfo_s *loadinfo,
|
|
FAR const Elf32_Shdr *relsec,
|
|
int index, FAR Elf32_Rel *rel)
|
|
{
|
|
off_t offset;
|
|
|
|
/* Verify that the symbol table index lies within symbol table */
|
|
|
|
if (index < 0 || index > (relsec->sh_size / sizeof(Elf32_Rel)))
|
|
{
|
|
sdbg("Bad relocation symbol index: %d\n", index);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Get the file offset to the symbol table entry */
|
|
|
|
offset = relsec->sh_offset + sizeof(Elf32_Rel) * index;
|
|
|
|
/* And, finally, read the symbol table entry into memory */
|
|
|
|
return mod_read(loadinfo, (FAR uint8_t *)rel, sizeof(Elf32_Rel), offset);
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: mod_relocate and mod_relocateadd
|
|
*
|
|
* Description:
|
|
* Perform all relocations associated with a section.
|
|
*
|
|
* Returned Value:
|
|
* 0 (OK) is returned on success and a negated errno is returned on
|
|
* failure.
|
|
*
|
|
****************************************************************************/
|
|
|
|
static int mod_relocate(FAR struct mod_loadinfo_s *loadinfo, int relidx)
|
|
|
|
{
|
|
FAR Elf32_Shdr *relsec = &loadinfo->shdr[relidx];
|
|
FAR Elf32_Shdr *dstsec = &loadinfo->shdr[relsec->sh_info];
|
|
Elf32_Rel rel;
|
|
Elf32_Sym sym;
|
|
FAR Elf32_Sym *psym;
|
|
uintptr_t addr;
|
|
int symidx;
|
|
int ret;
|
|
int i;
|
|
|
|
/* Examine each relocation in the section. 'relsec' is the section
|
|
* containing the relations. 'dstsec' is the section containing the data
|
|
* to be relocated.
|
|
*/
|
|
|
|
for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++)
|
|
{
|
|
psym = &sym;
|
|
|
|
/* Read the relocation entry into memory */
|
|
|
|
ret = mod_readrel(loadinfo, relsec, i, &rel);
|
|
if (ret < 0)
|
|
{
|
|
sdbg("Section %d reloc %d: Failed to read relocation entry: %d\n",
|
|
relidx, i, ret);
|
|
return ret;
|
|
}
|
|
|
|
/* Get the symbol table index for the relocation. This is contained
|
|
* in a bit-field within the r_info element.
|
|
*/
|
|
|
|
symidx = ELF32_R_SYM(rel.r_info);
|
|
|
|
/* Read the symbol table entry into memory */
|
|
|
|
ret = mod_readsym(loadinfo, symidx, &sym);
|
|
if (ret < 0)
|
|
{
|
|
sdbg("Section %d reloc %d: Failed to read symbol[%d]: %d\n",
|
|
relidx, i, symidx, ret);
|
|
return ret;
|
|
}
|
|
|
|
/* Get the value of the symbol (in sym.st_value) */
|
|
|
|
ret = mod_symvalue(loadinfo, &sym);
|
|
if (ret < 0)
|
|
{
|
|
/* The special error -ESRCH is returned only in one condition: The
|
|
* symbol has no name.
|
|
*
|
|
* There are a few relocations for a few architectures that do
|
|
* no depend upon a named symbol. We don't know if that is the
|
|
* case here, but we will use a NULL symbol pointer to indicate
|
|
* that case to up_relocate(). That function can then do what
|
|
* is best.
|
|
*/
|
|
|
|
if (ret == -ESRCH)
|
|
{
|
|
sdbg("Section %d reloc %d: Undefined symbol[%d] has no name: %d\n",
|
|
relidx, i, symidx, ret);
|
|
psym = NULL;
|
|
}
|
|
else
|
|
{
|
|
sdbg("Section %d reloc %d: Failed to get value of symbol[%d]: %d\n",
|
|
relidx, i, symidx, ret);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
/* Calculate the relocation address. */
|
|
|
|
if (rel.r_offset < 0 || rel.r_offset > dstsec->sh_size - sizeof(uint32_t))
|
|
{
|
|
sdbg("Section %d reloc %d: Relocation address out of range, offset %d size %d\n",
|
|
relidx, i, rel.r_offset, dstsec->sh_size);
|
|
return -EINVAL;
|
|
}
|
|
|
|
addr = dstsec->sh_addr + rel.r_offset;
|
|
|
|
/* Now perform the architecture-specific relocation */
|
|
|
|
ret = up_relocate(&rel, psym, addr);
|
|
if (ret < 0)
|
|
{
|
|
sdbg("ERROR: Section %d reloc %d: Relocation failed: %d\n", relidx, i, ret);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
return OK;
|
|
}
|
|
|
|
static int mod_relocateadd(FAR struct mod_loadinfo_s *loadinfo, int relidx)
|
|
{
|
|
sdbg("Not implemented\n");
|
|
return -ENOSYS;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: mod_bind
|
|
*
|
|
* Description:
|
|
* Bind the imported symbol names in the loaded module described by
|
|
* 'loadinfo' using the exported symbol values provided by mod_setsymtab().
|
|
*
|
|
* Returned Value:
|
|
* 0 (OK) is returned on success and a negated errno is returned on
|
|
* failure.
|
|
*
|
|
****************************************************************************/
|
|
|
|
int mod_bind(FAR struct mod_loadinfo_s *loadinfo)
|
|
{
|
|
int ret;
|
|
int i;
|
|
|
|
/* Find the symbol and string tables */
|
|
|
|
ret = mod_findsymtab(loadinfo);
|
|
if (ret < 0)
|
|
{
|
|
return ret;
|
|
}
|
|
|
|
/* Allocate an I/O buffer. This buffer is used by mod_symname() to
|
|
* accumulate the variable length symbol name.
|
|
*/
|
|
|
|
ret = mod_allocbuffer(loadinfo);
|
|
if (ret < 0)
|
|
{
|
|
sdbg("mod_allocbuffer failed: %d\n", ret);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* Process relocations in every allocated section */
|
|
|
|
for (i = 1; i < loadinfo->ehdr.e_shnum; i++)
|
|
{
|
|
/* Get the index to the relocation section */
|
|
|
|
int infosec = loadinfo->shdr[i].sh_info;
|
|
if (infosec >= loadinfo->ehdr.e_shnum)
|
|
{
|
|
continue;
|
|
}
|
|
|
|
/* Make sure that the section is allocated. We can't relocated
|
|
* sections that were not loaded into memory.
|
|
*/
|
|
|
|
if ((loadinfo->shdr[infosec].sh_flags & SHF_ALLOC) == 0)
|
|
{
|
|
continue;
|
|
}
|
|
|
|
/* Process the relocations by type */
|
|
|
|
if (loadinfo->shdr[i].sh_type == SHT_REL)
|
|
{
|
|
ret = mod_relocate(loadinfo, i);
|
|
}
|
|
else if (loadinfo->shdr[i].sh_type == SHT_RELA)
|
|
{
|
|
ret = mod_relocateadd(loadinfo, i);
|
|
}
|
|
|
|
if (ret < 0)
|
|
{
|
|
break;
|
|
}
|
|
}
|
|
|
|
#if defined(CONFIG_ARCH_HAVE_COHERENT_DCACHE)
|
|
/* Ensure that the I and D caches are coherent before starting the newly
|
|
* loaded module by cleaning the D cache (i.e., flushing the D cache
|
|
* contents to memory and invalidating the I cache).
|
|
*/
|
|
|
|
up_coherent_dcache(loadinfo->textalloc, loadinfo->textsize);
|
|
up_coherent_dcache(loadinfo->datastart, loadinfo->datasize);
|
|
|
|
#endif
|
|
|
|
return ret;
|
|
}
|