1/*
2 * linux/arch/unicore32/kernel/module.c
3 *
4 * Code specific to PKUnity SoC and UniCore ISA
5 *
6 * Copyright (C) 2001-2010 GUAN Xue-tao
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12#include <linux/module.h>
13#include <linux/moduleloader.h>
14#include <linux/kernel.h>
15#include <linux/mm.h>
16#include <linux/elf.h>
17#include <linux/vmalloc.h>
18#include <linux/fs.h>
19#include <linux/string.h>
20#include <linux/gfp.h>
21
22#include <asm/pgtable.h>
23#include <asm/sections.h>
24
25void *module_alloc(unsigned long size)
26{
27	struct vm_struct *area;
28
29	size = PAGE_ALIGN(size);
30	if (!size)
31		return NULL;
32
33	area = __get_vm_area(size, VM_ALLOC, MODULES_VADDR, MODULES_END);
34	if (!area)
35		return NULL;
36
37	return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL_EXEC);
38}
39
40int
41apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
42	       unsigned int relindex, struct module *module)
43{
44	Elf32_Shdr *symsec = sechdrs + symindex;
45	Elf32_Shdr *relsec = sechdrs + relindex;
46	Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
47	Elf32_Rel *rel = (void *)relsec->sh_addr;
48	unsigned int i;
49
50	for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
51		unsigned long loc;
52		Elf32_Sym *sym;
53		s32 offset;
54
55		offset = ELF32_R_SYM(rel->r_info);
56		if (offset < 0 || offset >
57				(symsec->sh_size / sizeof(Elf32_Sym))) {
58			printk(KERN_ERR "%s: bad relocation, "
59					"section %d reloc %d\n",
60					module->name, relindex, i);
61			return -ENOEXEC;
62		}
63
64		sym = ((Elf32_Sym *)symsec->sh_addr) + offset;
65
66		if (rel->r_offset < 0 || rel->r_offset >
67				dstsec->sh_size - sizeof(u32)) {
68			printk(KERN_ERR "%s: out of bounds relocation, "
69				"section %d reloc %d offset %d size %d\n",
70				module->name, relindex, i, rel->r_offset,
71				dstsec->sh_size);
72			return -ENOEXEC;
73		}
74
75		loc = dstsec->sh_addr + rel->r_offset;
76
77		switch (ELF32_R_TYPE(rel->r_info)) {
78		case R_UNICORE_NONE:
79			/* ignore */
80			break;
81
82		case R_UNICORE_ABS32:
83			*(u32 *)loc += sym->st_value;
84			break;
85
86		case R_UNICORE_PC24:
87		case R_UNICORE_CALL:
88		case R_UNICORE_JUMP24:
89			offset = (*(u32 *)loc & 0x00ffffff) << 2;
90			if (offset & 0x02000000)
91				offset -= 0x04000000;
92
93			offset += sym->st_value - loc;
94			if (offset & 3 ||
95			    offset <= (s32)0xfe000000 ||
96			    offset >= (s32)0x02000000) {
97				printk(KERN_ERR
98				       "%s: relocation out of range, section "
99				       "%d reloc %d sym '%s'\n", module->name,
100				       relindex, i, strtab + sym->st_name);
101				return -ENOEXEC;
102			}
103
104			offset >>= 2;
105
106			*(u32 *)loc &= 0xff000000;
107			*(u32 *)loc |= offset & 0x00ffffff;
108			break;
109
110		default:
111			printk(KERN_ERR "%s: unknown relocation: %u\n",
112			       module->name, ELF32_R_TYPE(rel->r_info));
113			return -ENOEXEC;
114		}
115	}
116	return 0;
117}
118