/* * 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/pgtable.h>#include <asm/homecache.h>#include <arch/opcode.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;	area->nr_pages = npages;	area->pages = pages; 	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); 	/* Globally flush the L1 icache. */	flush_remote(0, HV_FLUSH_EVICT_L1I, cpu_online_mask,		     0, 0, 0, NULL, NULL, 0); 	/*	 * FIXME: If module_region == mod->module_init, trim exception	 * table entries.	 */} #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)) { #ifdef __LITTLE_ENDIAN# define MUNGE(func) \	(*location = ((*location & ~func(-1)) | func(value)))#else/* * Instructions are always little-endian, so when we read them as data, * we have to swap them around before and after modifying them. */# define MUNGE(func) \	(*location = swab64((swab64(*location) & ~func(-1)) | func(value)))#endif #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;}