Skip to content

Commit

Permalink
nds32: Loadable modules
Browse files Browse the repository at this point in the history 
This patch adds support for loadable modules.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by:  Arnd Bergmann <arnd@arndb.de>
  • Loading branch information
Greentime Hu committed Feb 22, 2018
1 parent 3af6e29 commit c9a4a8d
Show file tree
Hide file tree
Showing 2 changed files with 289 additions and 0 deletions.
11 changes: 11 additions & 0 deletions arch/nds32/include/asm/module.h
View file
Original file line number Diff line number Diff line change
@@ -0,0 +1,11 @@
// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2005-2017 Andes Technology Corporation

#ifndef _ASM_NDS32_MODULE_H
#define _ASM_NDS32_MODULE_H

#include <asm-generic/module.h>

#define MODULE_ARCH_VERMAGIC "NDS32v3"

#endif /* _ASM_NDS32_MODULE_H */
278 changes: 278 additions & 0 deletions arch/nds32/kernel/module.c
View file
Original file line number Diff line number Diff line change
@@ -0,0 +1,278 @@
// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2005-2017 Andes Technology Corporation

#include <linux/module.h>
#include <linux/elf.h>
#include <linux/vmalloc.h>
#include <linux/moduleloader.h>
#include <asm/pgtable.h>

void *module_alloc(unsigned long size)
{
return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE,
__builtin_return_address(0));
}

void module_free(struct module *module, void *region)
{
vfree(region);
}

int module_frob_arch_sections(Elf_Ehdr * hdr,
Elf_Shdr * sechdrs,
char *secstrings, struct module *mod)
{
return 0;
}

void do_reloc16(unsigned int val, unsigned int *loc, unsigned int val_mask,
unsigned int val_shift, unsigned int loc_mask,
unsigned int partial_in_place, unsigned int swap)
{
unsigned int tmp = 0, tmp2 = 0;

__asm__ __volatile__("\tlhi.bi\t%0, [%2], 0\n"
"\tbeqz\t%3, 1f\n"
"\twsbh\t%0, %1\n"
"1:\n":"=r"(tmp):"0"(tmp), "r"(loc), "r"(swap)
);

tmp2 = tmp & loc_mask;
if (partial_in_place) {
tmp &= (!loc_mask);
tmp =
tmp2 | ((tmp + ((val & val_mask) >> val_shift)) & val_mask);
} else {
tmp = tmp2 | ((val & val_mask) >> val_shift);
}

__asm__ __volatile__("\tbeqz\t%3, 2f\n"
"\twsbh\t%0, %1\n"
"2:\n"
"\tshi.bi\t%0, [%2], 0\n":"=r"(tmp):"0"(tmp),
"r"(loc), "r"(swap)
);
}

void do_reloc32(unsigned int val, unsigned int *loc, unsigned int val_mask,
unsigned int val_shift, unsigned int loc_mask,
unsigned int partial_in_place, unsigned int swap)
{
unsigned int tmp = 0, tmp2 = 0;

__asm__ __volatile__("\tlmw.bi\t%0, [%2], %0, 0\n"
"\tbeqz\t%3, 1f\n"
"\twsbh\t%0, %1\n"
"\trotri\t%0, %1, 16\n"
"1:\n":"=r"(tmp):"0"(tmp), "r"(loc), "r"(swap)
);

tmp2 = tmp & loc_mask;
if (partial_in_place) {
tmp &= (!loc_mask);
tmp =
tmp2 | ((tmp + ((val & val_mask) >> val_shift)) & val_mask);
} else {
tmp = tmp2 | ((val & val_mask) >> val_shift);
}

__asm__ __volatile__("\tbeqz\t%3, 2f\n"
"\twsbh\t%0, %1\n"
"\trotri\t%0, %1, 16\n"
"2:\n"
"\tsmw.bi\t%0, [%2], %0, 0\n":"=r"(tmp):"0"(tmp),
"r"(loc), "r"(swap)
);
}

static inline int exceed_limit(int offset, unsigned int val_mask,
struct module *module, Elf32_Rela * rel,
unsigned int relindex, unsigned int reloc_order)
{
int abs_off = offset < 0 ? ~offset : offset;

if (abs_off & (~val_mask)) {
pr_err("\n%s: relocation type %d out of range.\n"
"please rebuild the kernel module with gcc option \"-Wa,-mno-small-text\".\n",
module->name, ELF32_R_TYPE(rel->r_info));
pr_err("section %d reloc %d offset 0x%x relative 0x%x.\n",
relindex, reloc_order, rel->r_offset, offset);
return true;
}
return false;
}

#ifdef __NDS32_EL__
#define NEED_SWAP 1
#else
#define NEED_SWAP 0
#endif

int
apply_relocate_add(Elf32_Shdr * sechdrs, const char *strtab,
unsigned int symindex, unsigned int relindex,
struct module *module)
{
Elf32_Shdr *symsec = sechdrs + symindex;
Elf32_Shdr *relsec = sechdrs + relindex;
Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
Elf32_Rela *rel = (void *)relsec->sh_addr;
unsigned int i;

for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rela); i++, rel++) {
Elf32_Addr *loc;
Elf32_Sym *sym;
Elf32_Addr v;
s32 offset;

offset = ELF32_R_SYM(rel->r_info);
if (offset < 0
|| offset > (symsec->sh_size / sizeof(Elf32_Sym))) {
pr_err("%s: bad relocation\n", module->name);
pr_err("section %d reloc %d\n", relindex, i);
return -ENOEXEC;
}

sym = ((Elf32_Sym *) symsec->sh_addr) + offset;

if (rel->r_offset < 0
|| rel->r_offset > dstsec->sh_size - sizeof(u16)) {
pr_err("%s: out of bounds relocation\n", module->name);
pr_err("section %d reloc %d offset 0x%0x size %d\n",
relindex, i, rel->r_offset, dstsec->sh_size);
return -ENOEXEC;
}

loc = (Elf32_Addr *) (dstsec->sh_addr + rel->r_offset);
v = sym->st_value + rel->r_addend;

switch (ELF32_R_TYPE(rel->r_info)) {
case R_NDS32_NONE:
case R_NDS32_INSN16:
case R_NDS32_LABEL:
case R_NDS32_LONGCALL1:
case R_NDS32_LONGCALL2:
case R_NDS32_LONGCALL3:
case R_NDS32_LONGCALL4:
case R_NDS32_LONGJUMP1:
case R_NDS32_LONGJUMP2:
case R_NDS32_LONGJUMP3:
case R_NDS32_9_FIXED_RELA:
case R_NDS32_15_FIXED_RELA:
case R_NDS32_17_FIXED_RELA:
case R_NDS32_25_FIXED_RELA:
case R_NDS32_LOADSTORE:
case R_NDS32_DWARF2_OP1_RELA:
case R_NDS32_DWARF2_OP2_RELA:
case R_NDS32_DWARF2_LEB_RELA:
case R_NDS32_RELA_NOP_MIX ... R_NDS32_RELA_NOP_MAX:
break;

case R_NDS32_32_RELA:
do_reloc32(v, loc, 0xffffffff, 0, 0, 0, 0);
break;

case R_NDS32_HI20_RELA:
do_reloc32(v, loc, 0xfffff000, 12, 0xfff00000, 0,
NEED_SWAP);
break;

case R_NDS32_LO12S3_RELA:
do_reloc32(v, loc, 0x00000fff, 3, 0xfffff000, 0,
NEED_SWAP);
break;

case R_NDS32_LO12S2_RELA:
do_reloc32(v, loc, 0x00000fff, 2, 0xfffff000, 0,
NEED_SWAP);
break;

case R_NDS32_LO12S1_RELA:
do_reloc32(v, loc, 0x00000fff, 1, 0xfffff000, 0,
NEED_SWAP);
break;

case R_NDS32_LO12S0_RELA:
case R_NDS32_LO12S0_ORI_RELA:
do_reloc32(v, loc, 0x00000fff, 0, 0xfffff000, 0,
NEED_SWAP);
break;

case R_NDS32_9_PCREL_RELA:
if (exceed_limit
((v - (Elf32_Addr) loc), 0x000000ff, module, rel,
relindex, i))
return -ENOEXEC;
do_reloc16(v - (Elf32_Addr) loc, loc, 0x000001ff, 1,
0xffffff00, 0, NEED_SWAP);
break;

case R_NDS32_15_PCREL_RELA:
if (exceed_limit
((v - (Elf32_Addr) loc), 0x00003fff, module, rel,
relindex, i))
return -ENOEXEC;
do_reloc32(v - (Elf32_Addr) loc, loc, 0x00007fff, 1,
0xffffc000, 0, NEED_SWAP);
break;

case R_NDS32_17_PCREL_RELA:
if (exceed_limit
((v - (Elf32_Addr) loc), 0x0000ffff, module, rel,
relindex, i))
return -ENOEXEC;
do_reloc32(v - (Elf32_Addr) loc, loc, 0x0001ffff, 1,
0xffff0000, 0, NEED_SWAP);
break;

case R_NDS32_25_PCREL_RELA:
if (exceed_limit
((v - (Elf32_Addr) loc), 0x00ffffff, module, rel,
relindex, i))
return -ENOEXEC;
do_reloc32(v - (Elf32_Addr) loc, loc, 0x01ffffff, 1,
0xff000000, 0, NEED_SWAP);
break;
case R_NDS32_WORD_9_PCREL_RELA:
if (exceed_limit
((v - (Elf32_Addr) loc), 0x000000ff, module, rel,
relindex, i))
return -ENOEXEC;
do_reloc32(v - (Elf32_Addr) loc, loc, 0x000001ff, 1,
0xffffff00, 0, NEED_SWAP);
break;

case R_NDS32_SDA15S3_RELA:
case R_NDS32_SDA15S2_RELA:
case R_NDS32_SDA15S1_RELA:
case R_NDS32_SDA15S0_RELA:
pr_err("%s: unsupported relocation type %d.\n",
module->name, ELF32_R_TYPE(rel->r_info));
pr_err
("Small data section access doesn't work in the kernel space; "
"please rebuild the kernel module with gcc option -mcmodel=large.\n");
pr_err("section %d reloc %d offset 0x%x size %d\n",
relindex, i, rel->r_offset, dstsec->sh_size);
break;

default:
pr_err("%s: unsupported relocation type %d.\n",
module->name, ELF32_R_TYPE(rel->r_info));
pr_err("section %d reloc %d offset 0x%x size %d\n",
relindex, i, rel->r_offset, dstsec->sh_size);
}
}
return 0;
}

int
module_finalize(const Elf32_Ehdr * hdr, const Elf_Shdr * sechdrs,
struct module *module)
{
return 0;
}

void module_arch_cleanup(struct module *mod)
{
}

0 comments on commit c9a4a8d

Please sign in to comment.