/*
* Copyright 2010 Tilera Corporation. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for
* more details.
*
* Based on i386 version, copyright (C) 2001 Rusty Russell.
*/
#include <linux/moduleloader.h>
#include <linux/elf.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <asm/opcode-tile.h>
#include <asm/pgtable.h>
#ifdef __tilegx__
# define Elf_Rela Elf64_Rela
# define ELF_R_SYM ELF64_R_SYM
# define ELF_R_TYPE ELF64_R_TYPE
#else
# define Elf_Rela Elf32_Rela
# define ELF_R_SYM ELF32_R_SYM
# define ELF_R_TYPE ELF32_R_TYPE
#endif
#ifdef MODULE_DEBUG
#define DEBUGP printk
#else
#define DEBUGP(fmt...)
#endif
/*
* Allocate some address space in the range MEM_MODULE_START to
* MEM_MODULE_END and populate it with memory.
*/
void *module_alloc(unsigned long size)
{
struct page **pages;
pgprot_t prot_rwx = __pgprot(_PAGE_KERNEL | _PAGE_KERNEL_EXEC);
struct vm_struct *area;
int i = 0;
int npages;
if (size == 0)
return NULL;
npages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
pages = kmalloc(npages * sizeof(struct page *), GFP_KERNEL);
if (pages == NULL)
return NULL;
for (; i < npages; ++i) {
pages[i] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
if (!pages[i])
goto error;
}
area = __get_vm_area(size, VM_ALLOC, MEM_MODULE_START, MEM_MODULE_END);
if (!area)
goto error;
if (map_vm_area(area, prot_rwx, &pages)) {
vunmap(area->addr);
goto error;
}
return area->addr;
error:
while (--i >= 0)
__free_page(pages[i]);
kfree(pages);
return NULL;
}
/* Free memory returned from module_alloc */
void module_free(struct module *mod, void *module_region)
{
vfree(module_region);
/*
* FIXME: If module_region == mod->init_region, trim exception
* table entries.
*/
}
/* We don't need anything special. */
int module_frob_arch_sections(Elf_Ehdr *hdr,
Elf_Shdr *sechdrs,
char *secstrings,
struct module *mod)
{
return 0;
}
int apply_relocate(Elf_Shdr *sechdrs,
const char *strtab,
unsigned int symindex,
unsigned int relsec,
struct module *me)
{
pr_err("module %s: .rel relocation unsupported\n", me->name);
return -ENOEXEC;
}
#ifdef __tilegx__
/*
* Validate that the high 16 bits of "value" is just the sign-extension of
* the low 48 bits.
*/
static int validate_hw2_last(long value, struct module *me)
{
if (((value << 16) >> 16) != value) {
pr_warning("module %s: Out of range HW2_LAST value %#lx\n",
me->name, value);
return 0;
}
return 1;
}
/*
* Validate that "value" isn't too big to hold in a JumpOff relocation.
*/
static int validate_jumpoff(long value)
{
/* Determine size of jump offset. */
int shift = __builtin_clzl(get_JumpOff_X1(create_JumpOff_X1(-1)));
/* Check to see if it fits into the relocation slot. */
long f = get_JumpOff_X1(create_JumpOff_X1(value));
f = (f << shift) >> shift;
return f == value;
}
#endif
int apply_relocate_add(Elf_Shdr *sechdrs,
const char *strtab,
unsigned int symindex,
unsigned int relsec,
struct module *me)
{
unsigned int i;
Elf_Rela *rel = (void *)sechdrs[relsec].sh_addr;
Elf_Sym *sym;
u64 *location;
unsigned long value;
DEBUGP("Applying relocate section %u to %u\n", relsec,
sechdrs[relsec].sh_info);
for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
/* This is where to make the change */
location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
+ rel[i].r_offset;
/*
* This is the symbol it is referring to.
* Note that all undefined symbols have been resolved.
*/
sym = (Elf_Sym *)sechdrs[symindex].sh_addr
+ ELF_R_SYM(rel[i].r_info);
value = sym->st_value + rel[i].r_addend;
switch (ELF_R_TYPE(rel[i].r_info)) {
#define MUNGE(func) (*location = ((*location & ~func(-1)) | func(value)))
#ifndef __tilegx__
case R_TILE_32:
*(uint32_t *)location = value;
break;
case R_TILE_IMM16_X0_HA:
value = (value + 0x8000) >> 16;
/*FALLTHROUGH*/
case R_TILE_IMM16_X0_LO:
MUNGE(create_Imm16_X0);
break;
case R_TILE_IMM16_X1_HA:
value = (value + 0x8000) >> 16;
/*FALLTHROUGH*/
case R_TILE_IMM16_X1_LO:
MUNGE(create_Imm16_X1);
break;
case R_TILE_JOFFLONG_X1:
value -= (unsigned long) location; /* pc-relative */
value = (long) value >> 3; /* count by instrs */
MUNGE(create_JOffLong_X1);
break;
#else
case R_TILEGX_64:
*location = value;
break;
case R_TILEGX_IMM16_X0_HW2_LAST:
if (!validate_hw2_last(value, me))
return -ENOEXEC;
value >>= 16;
/*FALLTHROUGH*/
case R_TILEGX_IMM16_X0_HW1:
value >>= 16;
/*FALLTHROUGH*/
case R_TILEGX_IMM16_X0_HW0:
MUNGE(create_Imm16_X0);
break;
case R_TILEGX_IMM16_X1_HW2_LAST:
if (!validate_hw2_last(value, me))
return -ENOEXEC;
value >>= 16;
/*FALLTHROUGH*/
case R_TILEGX_IMM16_X1_HW1:
value >>= 16;
/*FALLTHROUGH*/
case R_TILEGX_IMM16_X1_HW0:
MUNGE(create_Imm16_X1);
break;
case R_TILEGX_JUMPOFF_X1:
value -= (unsigned long) location; /* pc-relative */
value = (long) value >> 3; /* count by instrs */
if (!validate_jumpoff(value)) {
pr_warning("module %s: Out of range jump to"
" %#llx at %#llx (%p)\n", me->name,
sym->st_value + rel[i].r_addend,
rel[i].r_offset, location);
return -ENOEXEC;
}
MUNGE(create_JumpOff_X1);
break;
#endif
#undef MUNGE
default:
pr_err("module %s: Unknown relocation: %d\n",
me->name, (int) ELF_R_TYPE(rel[i].r_info));
return -ENOEXEC;
}
}
return 0;
}
int module_finalize(const Elf_Ehdr *hdr,
const Elf_Shdr *sechdrs,
struct module *me)
{
/* FIXME: perhaps remove the "writable" bit from the TLB? */
return 0;
}
void module_arch_cleanup(struct module *mod)
{
}