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git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blob - arch/arm/kernel/module.c
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/smp_plat.h>
26 #include <asm/unwind.h>
28 #ifdef CONFIG_XIP_KERNEL
30 * The XIP kernel text is mapped in the module area for modules and
31 * some other stuff to work without any indirect relocations.
32 * MODULES_VADDR is redefined here and not in asm/memory.h to avoid
33 * recompiling the whole kernel when CONFIG_XIP_KERNEL is turned on/off.
36 #define MODULES_VADDR (((unsigned long)_etext + ~PMD_MASK) & PMD_MASK)
40 void *module_alloc(unsigned long size
)
42 return __vmalloc_node_range(size
, 1, MODULES_VADDR
, MODULES_END
,
43 GFP_KERNEL
, PAGE_KERNEL_EXEC
, -1,
44 __builtin_return_address(0));
49 apply_relocate(Elf32_Shdr
*sechdrs
, const char *strtab
, unsigned int symindex
,
50 unsigned int relindex
, struct module
*module
)
52 Elf32_Shdr
*symsec
= sechdrs
+ symindex
;
53 Elf32_Shdr
*relsec
= sechdrs
+ relindex
;
54 Elf32_Shdr
*dstsec
= sechdrs
+ relsec
->sh_info
;
55 Elf32_Rel
*rel
= (void *)relsec
->sh_addr
;
58 for (i
= 0; i
< relsec
->sh_size
/ sizeof(Elf32_Rel
); i
++, rel
++) {
63 #ifdef CONFIG_THUMB2_KERNEL
64 u32 upper
, lower
, sign
, j1
, j2
;
67 offset
= ELF32_R_SYM(rel
->r_info
);
68 if (offset
< 0 || offset
> (symsec
->sh_size
/ sizeof(Elf32_Sym
))) {
69 pr_err("%s: section %u reloc %u: bad relocation sym offset\n",
70 module
->name
, relindex
, i
);
74 sym
= ((Elf32_Sym
*)symsec
->sh_addr
) + offset
;
75 symname
= strtab
+ sym
->st_name
;
77 if (rel
->r_offset
< 0 || rel
->r_offset
> dstsec
->sh_size
- sizeof(u32
)) {
78 pr_err("%s: section %u reloc %u sym '%s': out of bounds relocation, offset %d size %u\n",
79 module
->name
, relindex
, i
, symname
,
80 rel
->r_offset
, dstsec
->sh_size
);
84 loc
= dstsec
->sh_addr
+ rel
->r_offset
;
86 switch (ELF32_R_TYPE(rel
->r_info
)) {
92 *(u32
*)loc
+= sym
->st_value
;
98 offset
= (*(u32
*)loc
& 0x00ffffff) << 2;
99 if (offset
& 0x02000000)
100 offset
-= 0x04000000;
102 offset
+= sym
->st_value
- loc
;
104 offset
<= (s32
)0xfe000000 ||
105 offset
>= (s32
)0x02000000) {
106 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
107 module
->name
, relindex
, i
, symname
,
108 ELF32_R_TYPE(rel
->r_info
), loc
,
115 *(u32
*)loc
&= 0xff000000;
116 *(u32
*)loc
|= offset
& 0x00ffffff;
120 /* Preserve Rm and the condition code. Alter
121 * other bits to re-code instruction as
124 *(u32
*)loc
&= 0xf000000f;
125 *(u32
*)loc
|= 0x01a0f000;
129 offset
= *(u32
*)loc
+ sym
->st_value
- loc
;
130 *(u32
*)loc
= offset
& 0x7fffffff;
133 case R_ARM_MOVW_ABS_NC
:
135 offset
= *(u32
*)loc
;
136 offset
= ((offset
& 0xf0000) >> 4) | (offset
& 0xfff);
137 offset
= (offset
^ 0x8000) - 0x8000;
139 offset
+= sym
->st_value
;
140 if (ELF32_R_TYPE(rel
->r_info
) == R_ARM_MOVT_ABS
)
143 *(u32
*)loc
&= 0xfff0f000;
144 *(u32
*)loc
|= ((offset
& 0xf000) << 4) |
148 #ifdef CONFIG_THUMB2_KERNEL
150 case R_ARM_THM_JUMP24
:
152 lower
= *(u16
*)(loc
+ 2);
155 * 25 bit signed address range (Thumb-2 BL and B.W
157 * S:I1:I2:imm10:imm11:0
159 * S = upper[10] = offset[24]
160 * I1 = ~(J1 ^ S) = offset[23]
161 * I2 = ~(J2 ^ S) = offset[22]
162 * imm10 = upper[9:0] = offset[21:12]
163 * imm11 = lower[10:0] = offset[11:1]
167 sign
= (upper
>> 10) & 1;
168 j1
= (lower
>> 13) & 1;
169 j2
= (lower
>> 11) & 1;
170 offset
= (sign
<< 24) | ((~(j1
^ sign
) & 1) << 23) |
171 ((~(j2
^ sign
) & 1) << 22) |
172 ((upper
& 0x03ff) << 12) |
173 ((lower
& 0x07ff) << 1);
174 if (offset
& 0x01000000)
175 offset
-= 0x02000000;
176 offset
+= sym
->st_value
- loc
;
179 * For function symbols, only Thumb addresses are
180 * allowed (no interworking).
182 * For non-function symbols, the destination
183 * has no specific ARM/Thumb disposition, so
184 * the branch is resolved under the assumption
185 * that interworking is not required.
187 if ((ELF32_ST_TYPE(sym
->st_info
) == STT_FUNC
&&
189 offset
<= (s32
)0xff000000 ||
190 offset
>= (s32
)0x01000000) {
191 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
192 module
->name
, relindex
, i
, symname
,
193 ELF32_R_TYPE(rel
->r_info
), loc
,
198 sign
= (offset
>> 24) & 1;
199 j1
= sign
^ (~(offset
>> 23) & 1);
200 j2
= sign
^ (~(offset
>> 22) & 1);
201 *(u16
*)loc
= (u16
)((upper
& 0xf800) | (sign
<< 10) |
202 ((offset
>> 12) & 0x03ff));
203 *(u16
*)(loc
+ 2) = (u16
)((lower
& 0xd000) |
204 (j1
<< 13) | (j2
<< 11) |
205 ((offset
>> 1) & 0x07ff));
208 case R_ARM_THM_MOVW_ABS_NC
:
209 case R_ARM_THM_MOVT_ABS
:
211 lower
= *(u16
*)(loc
+ 2);
214 * MOVT/MOVW instructions encoding in Thumb-2:
218 * imm3 = lower[14:12]
221 * imm16 = imm4:i:imm3:imm8
223 offset
= ((upper
& 0x000f) << 12) |
224 ((upper
& 0x0400) << 1) |
225 ((lower
& 0x7000) >> 4) | (lower
& 0x00ff);
226 offset
= (offset
^ 0x8000) - 0x8000;
227 offset
+= sym
->st_value
;
229 if (ELF32_R_TYPE(rel
->r_info
) == R_ARM_THM_MOVT_ABS
)
232 *(u16
*)loc
= (u16
)((upper
& 0xfbf0) |
233 ((offset
& 0xf000) >> 12) |
234 ((offset
& 0x0800) >> 1));
235 *(u16
*)(loc
+ 2) = (u16
)((lower
& 0x8f00) |
236 ((offset
& 0x0700) << 4) |
242 printk(KERN_ERR
"%s: unknown relocation: %u\n",
243 module
->name
, ELF32_R_TYPE(rel
->r_info
));
250 struct mod_unwind_map
{
251 const Elf_Shdr
*unw_sec
;
252 const Elf_Shdr
*txt_sec
;
255 static const Elf_Shdr
*find_mod_section(const Elf32_Ehdr
*hdr
,
256 const Elf_Shdr
*sechdrs
, const char *name
)
258 const Elf_Shdr
*s
, *se
;
259 const char *secstrs
= (void *)hdr
+ sechdrs
[hdr
->e_shstrndx
].sh_offset
;
261 for (s
= sechdrs
, se
= sechdrs
+ hdr
->e_shnum
; s
< se
; s
++)
262 if (strcmp(name
, secstrs
+ s
->sh_name
) == 0)
268 extern void fixup_pv_table(const void *, unsigned long);
269 extern void fixup_smp(const void *, unsigned long);
271 int module_finalize(const Elf32_Ehdr
*hdr
, const Elf_Shdr
*sechdrs
,
274 const Elf_Shdr
*s
= NULL
;
275 #ifdef CONFIG_ARM_UNWIND
276 const char *secstrs
= (void *)hdr
+ sechdrs
[hdr
->e_shstrndx
].sh_offset
;
277 const Elf_Shdr
*sechdrs_end
= sechdrs
+ hdr
->e_shnum
;
278 struct mod_unwind_map maps
[ARM_SEC_MAX
];
281 memset(maps
, 0, sizeof(maps
));
283 for (s
= sechdrs
; s
< sechdrs_end
; s
++) {
284 const char *secname
= secstrs
+ s
->sh_name
;
286 if (!(s
->sh_flags
& SHF_ALLOC
))
289 if (strcmp(".ARM.exidx.init.text", secname
) == 0)
290 maps
[ARM_SEC_INIT
].unw_sec
= s
;
291 else if (strcmp(".ARM.exidx.devinit.text", secname
) == 0)
292 maps
[ARM_SEC_DEVINIT
].unw_sec
= s
;
293 else if (strcmp(".ARM.exidx", secname
) == 0)
294 maps
[ARM_SEC_CORE
].unw_sec
= s
;
295 else if (strcmp(".ARM.exidx.exit.text", secname
) == 0)
296 maps
[ARM_SEC_EXIT
].unw_sec
= s
;
297 else if (strcmp(".ARM.exidx.devexit.text", secname
) == 0)
298 maps
[ARM_SEC_DEVEXIT
].unw_sec
= s
;
299 else if (strcmp(".init.text", secname
) == 0)
300 maps
[ARM_SEC_INIT
].txt_sec
= s
;
301 else if (strcmp(".devinit.text", secname
) == 0)
302 maps
[ARM_SEC_DEVINIT
].txt_sec
= s
;
303 else if (strcmp(".text", secname
) == 0)
304 maps
[ARM_SEC_CORE
].txt_sec
= s
;
305 else if (strcmp(".exit.text", secname
) == 0)
306 maps
[ARM_SEC_EXIT
].txt_sec
= s
;
307 else if (strcmp(".devexit.text", secname
) == 0)
308 maps
[ARM_SEC_DEVEXIT
].txt_sec
= s
;
311 for (i
= 0; i
< ARM_SEC_MAX
; i
++)
312 if (maps
[i
].unw_sec
&& maps
[i
].txt_sec
)
313 mod
->arch
.unwind
[i
] =
314 unwind_table_add(maps
[i
].unw_sec
->sh_addr
,
315 maps
[i
].unw_sec
->sh_size
,
316 maps
[i
].txt_sec
->sh_addr
,
317 maps
[i
].txt_sec
->sh_size
);
319 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT
320 s
= find_mod_section(hdr
, sechdrs
, ".pv_table");
322 fixup_pv_table((void *)s
->sh_addr
, s
->sh_size
);
324 s
= find_mod_section(hdr
, sechdrs
, ".alt.smp.init");
326 #ifdef CONFIG_SMP_ON_UP
327 fixup_smp((void *)s
->sh_addr
, s
->sh_size
);
335 module_arch_cleanup(struct module
*mod
)
337 #ifdef CONFIG_ARM_UNWIND
340 for (i
= 0; i
< ARM_SEC_MAX
; i
++)
341 if (mod
->arch
.unwind
[i
])
342 unwind_table_del(mod
->arch
.unwind
[i
]);