2 * linux/arch/arm/kernel/module.c
4 * Copyright (C) 2002 Russell King.
5 * Modified for nommu by Hyok S. Choi
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 * Module allocation method suggested by Andi Kleen.
13 #include <linux/module.h>
14 #include <linux/moduleloader.h>
15 #include <linux/kernel.h>
17 #include <linux/elf.h>
18 #include <linux/vmalloc.h>
20 #include <linux/string.h>
21 #include <linux/gfp.h>
23 #include <asm/pgtable.h>
24 #include <asm/sections.h>
25 #include <asm/unwind.h>
27 #ifdef CONFIG_XIP_KERNEL
29 * The XIP kernel text is mapped in the module area for modules and
30 * some other stuff to work without any indirect relocations.
31 * MODULES_VADDR is redefined here and not in asm/memory.h to avoid
32 * recompiling the whole kernel when CONFIG_XIP_KERNEL is turned on/off.
35 #define MODULES_VADDR (((unsigned long)_etext + ~PGDIR_MASK) & PGDIR_MASK)
39 void *module_alloc(unsigned long size
)
41 struct vm_struct
*area
;
43 size
= PAGE_ALIGN(size
);
47 area
= __get_vm_area(size
, VM_ALLOC
, MODULES_VADDR
, MODULES_END
);
51 return __vmalloc_area(area
, GFP_KERNEL
, PAGE_KERNEL_EXEC
);
53 #else /* CONFIG_MMU */
54 void *module_alloc(unsigned long size
)
56 return size
== 0 ? NULL
: vmalloc(size
);
58 #endif /* !CONFIG_MMU */
60 void module_free(struct module
*module
, void *region
)
65 int module_frob_arch_sections(Elf_Ehdr
*hdr
,
70 #ifdef CONFIG_ARM_UNWIND
71 Elf_Shdr
*s
, *sechdrs_end
= sechdrs
+ hdr
->e_shnum
;
73 for (s
= sechdrs
; s
< sechdrs_end
; s
++) {
74 if (strcmp(".ARM.exidx.init.text", secstrings
+ s
->sh_name
) == 0)
75 mod
->arch
.unw_sec_init
= s
;
76 else if (strcmp(".ARM.exidx.devinit.text", secstrings
+ s
->sh_name
) == 0)
77 mod
->arch
.unw_sec_devinit
= s
;
78 else if (strcmp(".ARM.exidx", secstrings
+ s
->sh_name
) == 0)
79 mod
->arch
.unw_sec_core
= s
;
80 else if (strcmp(".init.text", secstrings
+ s
->sh_name
) == 0)
81 mod
->arch
.sec_init_text
= s
;
82 else if (strcmp(".devinit.text", secstrings
+ s
->sh_name
) == 0)
83 mod
->arch
.sec_devinit_text
= s
;
84 else if (strcmp(".text", secstrings
+ s
->sh_name
) == 0)
85 mod
->arch
.sec_core_text
= s
;
92 apply_relocate(Elf32_Shdr
*sechdrs
, const char *strtab
, unsigned int symindex
,
93 unsigned int relindex
, struct module
*module
)
95 Elf32_Shdr
*symsec
= sechdrs
+ symindex
;
96 Elf32_Shdr
*relsec
= sechdrs
+ relindex
;
97 Elf32_Shdr
*dstsec
= sechdrs
+ relsec
->sh_info
;
98 Elf32_Rel
*rel
= (void *)relsec
->sh_addr
;
101 for (i
= 0; i
< relsec
->sh_size
/ sizeof(Elf32_Rel
); i
++, rel
++) {
105 u32 upper
, lower
, sign
, j1
, j2
;
107 offset
= ELF32_R_SYM(rel
->r_info
);
108 if (offset
< 0 || offset
> (symsec
->sh_size
/ sizeof(Elf32_Sym
))) {
109 printk(KERN_ERR
"%s: bad relocation, section %d reloc %d\n",
110 module
->name
, relindex
, i
);
114 sym
= ((Elf32_Sym
*)symsec
->sh_addr
) + offset
;
116 if (rel
->r_offset
< 0 || rel
->r_offset
> dstsec
->sh_size
- sizeof(u32
)) {
117 printk(KERN_ERR
"%s: out of bounds relocation, "
118 "section %d reloc %d offset %d size %d\n",
119 module
->name
, relindex
, i
, rel
->r_offset
,
124 loc
= dstsec
->sh_addr
+ rel
->r_offset
;
126 switch (ELF32_R_TYPE(rel
->r_info
)) {
132 *(u32
*)loc
+= sym
->st_value
;
138 offset
= (*(u32
*)loc
& 0x00ffffff) << 2;
139 if (offset
& 0x02000000)
140 offset
-= 0x04000000;
142 offset
+= sym
->st_value
- loc
;
144 offset
<= (s32
)0xfe000000 ||
145 offset
>= (s32
)0x02000000) {
147 "%s: relocation out of range, section "
148 "%d reloc %d sym '%s'\n", module
->name
,
149 relindex
, i
, strtab
+ sym
->st_name
);
155 *(u32
*)loc
&= 0xff000000;
156 *(u32
*)loc
|= offset
& 0x00ffffff;
160 /* Preserve Rm and the condition code. Alter
161 * other bits to re-code instruction as
164 *(u32
*)loc
&= 0xf000000f;
165 *(u32
*)loc
|= 0x01a0f000;
169 offset
= *(u32
*)loc
+ sym
->st_value
- loc
;
170 *(u32
*)loc
= offset
& 0x7fffffff;
173 case R_ARM_MOVW_ABS_NC
:
175 offset
= *(u32
*)loc
;
176 offset
= ((offset
& 0xf0000) >> 4) | (offset
& 0xfff);
177 offset
= (offset
^ 0x8000) - 0x8000;
179 offset
+= sym
->st_value
;
180 if (ELF32_R_TYPE(rel
->r_info
) == R_ARM_MOVT_ABS
)
183 *(u32
*)loc
&= 0xfff0f000;
184 *(u32
*)loc
|= ((offset
& 0xf000) << 4) |
189 case R_ARM_THM_JUMP24
:
191 lower
= *(u16
*)(loc
+ 2);
194 * 25 bit signed address range (Thumb-2 BL and B.W
196 * S:I1:I2:imm10:imm11:0
198 * S = upper[10] = offset[24]
199 * I1 = ~(J1 ^ S) = offset[23]
200 * I2 = ~(J2 ^ S) = offset[22]
201 * imm10 = upper[9:0] = offset[21:12]
202 * imm11 = lower[10:0] = offset[11:1]
206 sign
= (upper
>> 10) & 1;
207 j1
= (lower
>> 13) & 1;
208 j2
= (lower
>> 11) & 1;
209 offset
= (sign
<< 24) | ((~(j1
^ sign
) & 1) << 23) |
210 ((~(j2
^ sign
) & 1) << 22) |
211 ((upper
& 0x03ff) << 12) |
212 ((lower
& 0x07ff) << 1);
213 if (offset
& 0x01000000)
214 offset
-= 0x02000000;
215 offset
+= sym
->st_value
- loc
;
217 /* only Thumb addresses allowed (no interworking) */
219 offset
<= (s32
)0xff000000 ||
220 offset
>= (s32
)0x01000000) {
222 "%s: relocation out of range, section "
223 "%d reloc %d sym '%s'\n", module
->name
,
224 relindex
, i
, strtab
+ sym
->st_name
);
228 sign
= (offset
>> 24) & 1;
229 j1
= sign
^ (~(offset
>> 23) & 1);
230 j2
= sign
^ (~(offset
>> 22) & 1);
231 *(u16
*)loc
= (u16
)((upper
& 0xf800) | (sign
<< 10) |
232 ((offset
>> 12) & 0x03ff));
233 *(u16
*)(loc
+ 2) = (u16
)((lower
& 0xd000) |
234 (j1
<< 13) | (j2
<< 11) |
235 ((offset
>> 1) & 0x07ff));
237 lower
= *(u16
*)(loc
+ 2);
241 printk(KERN_ERR
"%s: unknown relocation: %u\n",
242 module
->name
, ELF32_R_TYPE(rel
->r_info
));
250 apply_relocate_add(Elf32_Shdr
*sechdrs
, const char *strtab
,
251 unsigned int symindex
, unsigned int relsec
, struct module
*module
)
253 printk(KERN_ERR
"module %s: ADD RELOCATION unsupported\n",
258 #ifdef CONFIG_ARM_UNWIND
259 static void register_unwind_tables(struct module
*mod
)
261 if (mod
->arch
.unw_sec_init
&& mod
->arch
.sec_init_text
)
262 mod
->arch
.unwind_init
=
263 unwind_table_add(mod
->arch
.unw_sec_init
->sh_addr
,
264 mod
->arch
.unw_sec_init
->sh_size
,
265 mod
->arch
.sec_init_text
->sh_addr
,
266 mod
->arch
.sec_init_text
->sh_size
);
267 if (mod
->arch
.unw_sec_devinit
&& mod
->arch
.sec_devinit_text
)
268 mod
->arch
.unwind_devinit
=
269 unwind_table_add(mod
->arch
.unw_sec_devinit
->sh_addr
,
270 mod
->arch
.unw_sec_devinit
->sh_size
,
271 mod
->arch
.sec_devinit_text
->sh_addr
,
272 mod
->arch
.sec_devinit_text
->sh_size
);
273 if (mod
->arch
.unw_sec_core
&& mod
->arch
.sec_core_text
)
274 mod
->arch
.unwind_core
=
275 unwind_table_add(mod
->arch
.unw_sec_core
->sh_addr
,
276 mod
->arch
.unw_sec_core
->sh_size
,
277 mod
->arch
.sec_core_text
->sh_addr
,
278 mod
->arch
.sec_core_text
->sh_size
);
281 static void unregister_unwind_tables(struct module
*mod
)
283 unwind_table_del(mod
->arch
.unwind_init
);
284 unwind_table_del(mod
->arch
.unwind_devinit
);
285 unwind_table_del(mod
->arch
.unwind_core
);
288 static inline void register_unwind_tables(struct module
*mod
) { }
289 static inline void unregister_unwind_tables(struct module
*mod
) { }
293 module_finalize(const Elf32_Ehdr
*hdr
, const Elf_Shdr
*sechdrs
,
294 struct module
*module
)
296 register_unwind_tables(module
);
301 module_arch_cleanup(struct module
*mod
)
303 unregister_unwind_tables(mod
);