139 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			139 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Kernel module support for Nios II.
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|  *
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|  * Copyright (C) 2004 Microtronix Datacom Ltd.
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|  *   Written by Wentao Xu <xuwentao@microtronix.com>
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|  * Copyright (C) 2001, 2003 Rusty Russell
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|  *
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|  * This file is subject to the terms and conditions of the GNU General
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|  * Public License.  See the file COPYING in the main directory of this
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|  * archive for more details.
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|  */
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| 
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| #include <linux/moduleloader.h>
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| #include <linux/elf.h>
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| #include <linux/mm.h>
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| #include <linux/vmalloc.h>
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| #include <linux/slab.h>
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| #include <linux/fs.h>
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| #include <linux/string.h>
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| #include <linux/kernel.h>
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| 
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| #include <asm/pgtable.h>
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| #include <asm/cacheflush.h>
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| 
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| /*
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|  * Modules should NOT be allocated with kmalloc for (obvious) reasons.
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|  * But we do it for now to avoid relocation issues. CALL26/PCREL26 cannot reach
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|  * from 0x80000000 (vmalloc area) to 0xc00000000 (kernel) (kmalloc returns
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|  * addresses in 0xc0000000)
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|  */
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| void *module_alloc(unsigned long size)
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| {
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| 	if (size == 0)
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| 		return NULL;
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| 	return kmalloc(size, GFP_KERNEL);
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| }
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| 
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| /* Free memory returned from module_alloc */
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| void module_memfree(void *module_region)
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| {
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| 	kfree(module_region);
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| }
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| 
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| int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
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| 			unsigned int symindex, unsigned int relsec,
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| 			struct module *mod)
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| {
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| 	unsigned int i;
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| 	Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr;
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| 
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| 	pr_debug("Applying relocate section %u to %u\n", relsec,
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| 		 sechdrs[relsec].sh_info);
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| 
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| 	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) {
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| 		/* This is where to make the change */
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| 		uint32_t word;
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| 		uint32_t *loc
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| 			= ((void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
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| 			   + rela[i].r_offset);
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| 		/* This is the symbol it is referring to.  Note that all
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| 		   undefined symbols have been resolved.  */
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| 		Elf32_Sym *sym
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| 			= ((Elf32_Sym *)sechdrs[symindex].sh_addr
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| 				+ ELF32_R_SYM(rela[i].r_info));
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| 		uint32_t v = sym->st_value + rela[i].r_addend;
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| 
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| 		pr_debug("reltype %d 0x%x name:<%s>\n",
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| 			ELF32_R_TYPE(rela[i].r_info),
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| 			rela[i].r_offset, strtab + sym->st_name);
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| 
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| 		switch (ELF32_R_TYPE(rela[i].r_info)) {
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| 		case R_NIOS2_NONE:
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| 			break;
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| 		case R_NIOS2_BFD_RELOC_32:
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| 			*loc += v;
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| 			break;
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| 		case R_NIOS2_PCREL16:
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| 			v -= (uint32_t)loc + 4;
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| 			if ((int32_t)v > 0x7fff ||
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| 				(int32_t)v < -(int32_t)0x8000) {
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| 				pr_err("module %s: relocation overflow\n",
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| 					mod->name);
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| 				return -ENOEXEC;
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| 			}
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| 			word = *loc;
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| 			*loc = ((((word >> 22) << 16) | (v & 0xffff)) << 6) |
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| 				(word & 0x3f);
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| 			break;
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| 		case R_NIOS2_CALL26:
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| 			if (v & 3) {
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| 				pr_err("module %s: dangerous relocation\n",
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| 					mod->name);
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| 				return -ENOEXEC;
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| 			}
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| 			if ((v >> 28) != ((uint32_t)loc >> 28)) {
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| 				pr_err("module %s: relocation overflow\n",
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| 					mod->name);
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| 				return -ENOEXEC;
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| 			}
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| 			*loc = (*loc & 0x3f) | ((v >> 2) << 6);
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| 			break;
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| 		case R_NIOS2_HI16:
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| 			word = *loc;
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| 			*loc = ((((word >> 22) << 16) |
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| 				((v >> 16) & 0xffff)) << 6) | (word & 0x3f);
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| 			break;
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| 		case R_NIOS2_LO16:
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| 			word = *loc;
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| 			*loc = ((((word >> 22) << 16) | (v & 0xffff)) << 6) |
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| 					(word & 0x3f);
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| 			break;
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| 		case R_NIOS2_HIADJ16:
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| 			{
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| 				Elf32_Addr word2;
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| 
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| 				word = *loc;
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| 				word2 = ((v >> 16) + ((v >> 15) & 1)) & 0xffff;
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| 				*loc = ((((word >> 22) << 16) | word2) << 6) |
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| 						(word & 0x3f);
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| 			}
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| 			break;
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| 
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| 		default:
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| 			pr_err("module %s: Unknown reloc: %u\n",
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| 				mod->name, ELF32_R_TYPE(rela[i].r_info));
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| 			return -ENOEXEC;
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| 		}
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| 	}
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| 
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| 	return 0;
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| }
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| 
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| int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
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| 			struct module *me)
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| {
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| 	flush_cache_all();
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| 	return 0;
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| }
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