diff options
Diffstat (limited to 'arch/tile/kernel/module.c')
| -rw-r--r-- | arch/tile/kernel/module.c | 257 |
1 files changed, 257 insertions, 0 deletions
diff --git a/arch/tile/kernel/module.c b/arch/tile/kernel/module.c new file mode 100644 index 00000000000..ed3e91161f8 --- /dev/null +++ b/arch/tile/kernel/module.c @@ -0,0 +1,257 @@ +/* + * 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) +{ + printk(KERN_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) { + printk("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)) { + printk("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: + printk(KERN_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) +{ +} |