1 // SPDX-License-Identifier: GPL-2.0+
2 /*  Kernel module help for SH.
3 
4     SHcompact version by Kaz Kojima and Paul Mundt.
5 
6     SHmedia bits:
7 
8 	Copyright 2004 SuperH (UK) Ltd
9 	Author: Richard Curnow
10 
11 	Based on the sh version, and on code from the sh64-specific parts of
12 	modutils, originally written by Richard Curnow and Ben Gaster.
13 */
14 #include <linux/moduleloader.h>
15 #include <linux/elf.h>
16 #include <linux/vmalloc.h>
17 #include <linux/bug.h>
18 #include <linux/fs.h>
19 #include <linux/string.h>
20 #include <linux/kernel.h>
21 #include <asm/unaligned.h>
22 #include <asm/dwarf.h>
23 
apply_relocate_add(Elf32_Shdr * sechdrs,const char * strtab,unsigned int symindex,unsigned int relsec,struct module * me)24 int apply_relocate_add(Elf32_Shdr *sechdrs,
25 		   const char *strtab,
26 		   unsigned int symindex,
27 		   unsigned int relsec,
28 		   struct module *me)
29 {
30 	unsigned int i;
31 	Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
32 	Elf32_Sym *sym;
33 	Elf32_Addr relocation;
34 	uint32_t *location;
35 	uint32_t value;
36 
37 	pr_debug("Applying relocate section %u to %u\n", relsec,
38 		 sechdrs[relsec].sh_info);
39 	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
40 		/* This is where to make the change */
41 		location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
42 			+ rel[i].r_offset;
43 		/* This is the symbol it is referring to.  Note that all
44 		   undefined symbols have been resolved.  */
45 		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
46 			+ ELF32_R_SYM(rel[i].r_info);
47 		relocation = sym->st_value + rel[i].r_addend;
48 
49 		switch (ELF32_R_TYPE(rel[i].r_info)) {
50 		case R_SH_NONE:
51 			break;
52 		case R_SH_DIR32:
53 			value = get_unaligned(location);
54 			value += relocation;
55 			put_unaligned(value, location);
56 			break;
57 		case R_SH_REL32:
58 			relocation = (relocation - (Elf32_Addr) location);
59 			value = get_unaligned(location);
60 			value += relocation;
61 			put_unaligned(value, location);
62 			break;
63 		case R_SH_IMM_LOW16:
64 			*location = (*location & ~0x3fffc00) |
65 				((relocation & 0xffff) << 10);
66 			break;
67 		case R_SH_IMM_MEDLOW16:
68 			*location = (*location & ~0x3fffc00) |
69 				(((relocation >> 16) & 0xffff) << 10);
70 			break;
71 		case R_SH_IMM_LOW16_PCREL:
72 			relocation -= (Elf32_Addr) location;
73 			*location = (*location & ~0x3fffc00) |
74 				((relocation & 0xffff) << 10);
75 			break;
76 		case R_SH_IMM_MEDLOW16_PCREL:
77 			relocation -= (Elf32_Addr) location;
78 			*location = (*location & ~0x3fffc00) |
79 				(((relocation >> 16) & 0xffff) << 10);
80 			break;
81 		default:
82 			printk(KERN_ERR "module %s: Unknown relocation: %u\n",
83 			       me->name, ELF32_R_TYPE(rel[i].r_info));
84 			return -ENOEXEC;
85 		}
86 	}
87 	return 0;
88 }
89 
module_finalize(const Elf_Ehdr * hdr,const Elf_Shdr * sechdrs,struct module * me)90 int module_finalize(const Elf_Ehdr *hdr,
91 		    const Elf_Shdr *sechdrs,
92 		    struct module *me)
93 {
94 	int ret = 0;
95 
96 	ret |= module_dwarf_finalize(hdr, sechdrs, me);
97 
98 	return ret;
99 }
100 
module_arch_cleanup(struct module * mod)101 void module_arch_cleanup(struct module *mod)
102 {
103 	module_dwarf_cleanup(mod);
104 }
105