module: cleanup FIXME comments about trimming exception table entries.
[deliverable/linux.git] / arch / parisc / kernel / module.c
CommitLineData
1da177e4
LT
1/* Kernel dynamically loadable module help for PARISC.
2 *
3 * The best reference for this stuff is probably the Processor-
4 * Specific ELF Supplement for PA-RISC:
5 * http://ftp.parisc-linux.org/docs/arch/elf-pa-hp.pdf
6 *
7 * Linux/PA-RISC Project (http://www.parisc-linux.org/)
8 * Copyright (C) 2003 Randolph Chung <tausq at debian . org>
c298be74 9 * Copyright (C) 2008 Helge Deller <deller@gmx.de>
1da177e4
LT
10 *
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 *
26 *
27 * Notes:
c298be74
HD
28 * - PLT stub handling
29 * On 32bit (and sometimes 64bit) and with big kernel modules like xfs or
30 * ipv6 the relocation types R_PARISC_PCREL17F and R_PARISC_PCREL22F may
31 * fail to reach their PLT stub if we only create one big stub array for
32 * all sections at the beginning of the core or init section.
33 * Instead we now insert individual PLT stub entries directly in front of
34 * of the code sections where the stubs are actually called.
35 * This reduces the distance between the PCREL location and the stub entry
36 * so that the relocations can be fulfilled.
37 * While calculating the final layout of the kernel module in memory, the
38 * kernel module loader calls arch_mod_section_prepend() to request the
39 * to be reserved amount of memory in front of each individual section.
40 *
1da177e4
LT
41 * - SEGREL32 handling
42 * We are not doing SEGREL32 handling correctly. According to the ABI, we
43 * should do a value offset, like this:
959ed340 44 * if (in_init(me, (void *)val))
1da177e4
LT
45 * val -= (uint32_t)me->module_init;
46 * else
47 * val -= (uint32_t)me->module_core;
48 * However, SEGREL32 is used only for PARISC unwind entries, and we want
49 * those entries to have an absolute address, and not just an offset.
50 *
51 * The unwind table mechanism has the ability to specify an offset for
52 * the unwind table; however, because we split off the init functions into
53 * a different piece of memory, it is not possible to do this using a
54 * single offset. Instead, we use the above hack for now.
55 */
56
57#include <linux/moduleloader.h>
58#include <linux/elf.h>
59#include <linux/vmalloc.h>
60#include <linux/fs.h>
61#include <linux/string.h>
62#include <linux/kernel.h>
6891f8a1 63#include <linux/bug.h>
1da177e4
LT
64
65#include <asm/unwind.h>
66
67#if 0
68#define DEBUGP printk
69#else
70#define DEBUGP(fmt...)
71#endif
72
c298be74
HD
73#define RELOC_REACHABLE(val, bits) \
74 (( ( !((val) & (1<<((bits)-1))) && ((val)>>(bits)) != 0 ) || \
75 ( ((val) & (1<<((bits)-1))) && ((val)>>(bits)) != (((__typeof__(val))(~0))>>((bits)+2)))) ? \
76 0 : 1)
77
1da177e4 78#define CHECK_RELOC(val, bits) \
c298be74 79 if (!RELOC_REACHABLE(val, bits)) { \
1da177e4
LT
80 printk(KERN_ERR "module %s relocation of symbol %s is out of range (0x%lx in %d bits)\n", \
81 me->name, strtab + sym->st_name, (unsigned long)val, bits); \
82 return -ENOEXEC; \
83 }
84
85/* Maximum number of GOT entries. We use a long displacement ldd from
86 * the bottom of the table, which has a maximum signed displacement of
87 * 0x3fff; however, since we're only going forward, this becomes
88 * 0x1fff, and thus, since each GOT entry is 8 bytes long we can have
89 * at most 1023 entries */
90#define MAX_GOTS 1023
91
92/* three functions to determine where in the module core
93 * or init pieces the location is */
959ed340 94static inline int in_init(struct module *me, void *loc)
1da177e4
LT
95{
96 return (loc >= me->module_init &&
97 loc <= (me->module_init + me->init_size));
98}
99
959ed340 100static inline int in_core(struct module *me, void *loc)
1da177e4
LT
101{
102 return (loc >= me->module_core &&
103 loc <= (me->module_core + me->core_size));
104}
105
959ed340 106static inline int in_local(struct module *me, void *loc)
1da177e4 107{
959ed340 108 return in_init(me, loc) || in_core(me, loc);
1da177e4
LT
109}
110
a8f44e38 111#ifndef CONFIG_64BIT
1da177e4
LT
112struct got_entry {
113 Elf32_Addr addr;
114};
115
1da177e4
LT
116struct stub_entry {
117 Elf32_Word insns[2]; /* each stub entry has two insns */
118};
119#else
120struct got_entry {
121 Elf64_Addr addr;
122};
123
1da177e4
LT
124struct stub_entry {
125 Elf64_Word insns[4]; /* each stub entry has four insns */
126};
127#endif
128
129/* Field selection types defined by hppa */
130#define rnd(x) (((x)+0x1000)&~0x1fff)
131/* fsel: full 32 bits */
132#define fsel(v,a) ((v)+(a))
133/* lsel: select left 21 bits */
134#define lsel(v,a) (((v)+(a))>>11)
135/* rsel: select right 11 bits */
136#define rsel(v,a) (((v)+(a))&0x7ff)
137/* lrsel with rounding of addend to nearest 8k */
138#define lrsel(v,a) (((v)+rnd(a))>>11)
139/* rrsel with rounding of addend to nearest 8k */
140#define rrsel(v,a) ((((v)+rnd(a))&0x7ff)+((a)-rnd(a)))
141
142#define mask(x,sz) ((x) & ~((1<<(sz))-1))
143
144
145/* The reassemble_* functions prepare an immediate value for
146 insertion into an opcode. pa-risc uses all sorts of weird bitfields
147 in the instruction to hold the value. */
148static inline int reassemble_14(int as14)
149{
150 return (((as14 & 0x1fff) << 1) |
151 ((as14 & 0x2000) >> 13));
152}
153
154static inline int reassemble_17(int as17)
155{
156 return (((as17 & 0x10000) >> 16) |
157 ((as17 & 0x0f800) << 5) |
158 ((as17 & 0x00400) >> 8) |
159 ((as17 & 0x003ff) << 3));
160}
161
162static inline int reassemble_21(int as21)
163{
164 return (((as21 & 0x100000) >> 20) |
165 ((as21 & 0x0ffe00) >> 8) |
166 ((as21 & 0x000180) << 7) |
167 ((as21 & 0x00007c) << 14) |
168 ((as21 & 0x000003) << 12));
169}
170
171static inline int reassemble_22(int as22)
172{
173 return (((as22 & 0x200000) >> 21) |
174 ((as22 & 0x1f0000) << 5) |
175 ((as22 & 0x00f800) << 5) |
176 ((as22 & 0x000400) >> 8) |
177 ((as22 & 0x0003ff) << 3));
178}
179
180void *module_alloc(unsigned long size)
181{
182 if (size == 0)
183 return NULL;
184 return vmalloc(size);
185}
186
a8f44e38 187#ifndef CONFIG_64BIT
1da177e4
LT
188static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
189{
190 return 0;
191}
192
193static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
194{
195 return 0;
196}
197
198static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
199{
200 unsigned long cnt = 0;
201
202 for (; n > 0; n--, rela++)
203 {
204 switch (ELF32_R_TYPE(rela->r_info)) {
205 case R_PARISC_PCREL17F:
206 case R_PARISC_PCREL22F:
207 cnt++;
208 }
209 }
210
211 return cnt;
212}
213#else
214static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
215{
216 unsigned long cnt = 0;
217
218 for (; n > 0; n--, rela++)
219 {
220 switch (ELF64_R_TYPE(rela->r_info)) {
221 case R_PARISC_LTOFF21L:
222 case R_PARISC_LTOFF14R:
223 case R_PARISC_PCREL22F:
224 cnt++;
225 }
226 }
227
228 return cnt;
229}
230
231static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
232{
233 unsigned long cnt = 0;
234
235 for (; n > 0; n--, rela++)
236 {
237 switch (ELF64_R_TYPE(rela->r_info)) {
238 case R_PARISC_FPTR64:
239 cnt++;
240 }
241 }
242
243 return cnt;
244}
245
246static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
247{
248 unsigned long cnt = 0;
249
250 for (; n > 0; n--, rela++)
251 {
252 switch (ELF64_R_TYPE(rela->r_info)) {
253 case R_PARISC_PCREL22F:
254 cnt++;
255 }
256 }
257
258 return cnt;
259}
260#endif
261
262
263/* Free memory returned from module_alloc */
264void module_free(struct module *mod, void *module_region)
265{
c298be74
HD
266 kfree(mod->arch.section);
267 mod->arch.section = NULL;
268
1da177e4 269 vfree(module_region);
1da177e4
LT
270}
271
c298be74
HD
272/* Additional bytes needed in front of individual sections */
273unsigned int arch_mod_section_prepend(struct module *mod,
274 unsigned int section)
275{
276 /* size needed for all stubs of this section (including
277 * one additional for correct alignment of the stubs) */
278 return (mod->arch.section[section].stub_entries + 1)
279 * sizeof(struct stub_entry);
280}
281
1da177e4
LT
282#define CONST
283int module_frob_arch_sections(CONST Elf_Ehdr *hdr,
284 CONST Elf_Shdr *sechdrs,
285 CONST char *secstrings,
286 struct module *me)
287{
c298be74 288 unsigned long gots = 0, fdescs = 0, len;
1da177e4
LT
289 unsigned int i;
290
c298be74
HD
291 len = hdr->e_shnum * sizeof(me->arch.section[0]);
292 me->arch.section = kzalloc(len, GFP_KERNEL);
293 if (!me->arch.section)
294 return -ENOMEM;
295
1da177e4 296 for (i = 1; i < hdr->e_shnum; i++) {
c298be74 297 const Elf_Rela *rels = (void *)sechdrs[i].sh_addr;
1da177e4 298 unsigned long nrels = sechdrs[i].sh_size / sizeof(*rels);
c298be74 299 unsigned int count, s;
1da177e4
LT
300
301 if (strncmp(secstrings + sechdrs[i].sh_name,
302 ".PARISC.unwind", 14) == 0)
303 me->arch.unwind_section = i;
304
305 if (sechdrs[i].sh_type != SHT_RELA)
306 continue;
307
308 /* some of these are not relevant for 32-bit/64-bit
309 * we leave them here to make the code common. the
310 * compiler will do its thing and optimize out the
311 * stuff we don't need
312 */
313 gots += count_gots(rels, nrels);
314 fdescs += count_fdescs(rels, nrels);
c298be74
HD
315
316 /* XXX: By sorting the relocs and finding duplicate entries
317 * we could reduce the number of necessary stubs and save
318 * some memory. */
319 count = count_stubs(rels, nrels);
320 if (!count)
321 continue;
322
323 /* so we need relocation stubs. reserve necessary memory. */
324 /* sh_info gives the section for which we need to add stubs. */
325 s = sechdrs[i].sh_info;
326
327 /* each code section should only have one relocation section */
328 WARN_ON(me->arch.section[s].stub_entries);
329
330 /* store number of stubs we need for this section */
331 me->arch.section[s].stub_entries += count;
1da177e4
LT
332 }
333
334 /* align things a bit */
335 me->core_size = ALIGN(me->core_size, 16);
336 me->arch.got_offset = me->core_size;
337 me->core_size += gots * sizeof(struct got_entry);
338
339 me->core_size = ALIGN(me->core_size, 16);
340 me->arch.fdesc_offset = me->core_size;
341 me->core_size += fdescs * sizeof(Elf_Fdesc);
342
1da177e4
LT
343 me->arch.got_max = gots;
344 me->arch.fdesc_max = fdescs;
1da177e4
LT
345
346 return 0;
347}
348
a8f44e38 349#ifdef CONFIG_64BIT
1da177e4
LT
350static Elf64_Word get_got(struct module *me, unsigned long value, long addend)
351{
352 unsigned int i;
353 struct got_entry *got;
354
355 value += addend;
356
357 BUG_ON(value == 0);
358
359 got = me->module_core + me->arch.got_offset;
360 for (i = 0; got[i].addr; i++)
361 if (got[i].addr == value)
362 goto out;
363
364 BUG_ON(++me->arch.got_count > me->arch.got_max);
365
366 got[i].addr = value;
367 out:
368 DEBUGP("GOT ENTRY %d[%x] val %lx\n", i, i*sizeof(struct got_entry),
369 value);
370 return i * sizeof(struct got_entry);
371}
a8f44e38 372#endif /* CONFIG_64BIT */
1da177e4 373
a8f44e38 374#ifdef CONFIG_64BIT
1da177e4
LT
375static Elf_Addr get_fdesc(struct module *me, unsigned long value)
376{
377 Elf_Fdesc *fdesc = me->module_core + me->arch.fdesc_offset;
378
379 if (!value) {
380 printk(KERN_ERR "%s: zero OPD requested!\n", me->name);
381 return 0;
382 }
383
384 /* Look for existing fdesc entry. */
385 while (fdesc->addr) {
386 if (fdesc->addr == value)
387 return (Elf_Addr)fdesc;
388 fdesc++;
389 }
390
391 BUG_ON(++me->arch.fdesc_count > me->arch.fdesc_max);
392
393 /* Create new one */
394 fdesc->addr = value;
395 fdesc->gp = (Elf_Addr)me->module_core + me->arch.got_offset;
396 return (Elf_Addr)fdesc;
397}
a8f44e38 398#endif /* CONFIG_64BIT */
1da177e4 399
6e1b9585
JB
400enum elf_stub_type {
401 ELF_STUB_GOT,
402 ELF_STUB_MILLI,
403 ELF_STUB_DIRECT,
404};
405
1da177e4 406static Elf_Addr get_stub(struct module *me, unsigned long value, long addend,
c298be74 407 enum elf_stub_type stub_type, Elf_Addr loc0, unsigned int targetsec)
1da177e4 408{
1da177e4
LT
409 struct stub_entry *stub;
410
c298be74
HD
411 /* initialize stub_offset to point in front of the section */
412 if (!me->arch.section[targetsec].stub_offset) {
413 loc0 -= (me->arch.section[targetsec].stub_entries + 1) *
414 sizeof(struct stub_entry);
415 /* get correct alignment for the stubs */
416 loc0 = ALIGN(loc0, sizeof(struct stub_entry));
417 me->arch.section[targetsec].stub_offset = loc0;
1da177e4
LT
418 }
419
c298be74
HD
420 /* get address of stub entry */
421 stub = (void *) me->arch.section[targetsec].stub_offset;
422 me->arch.section[targetsec].stub_offset += sizeof(struct stub_entry);
423
424 /* do not write outside available stub area */
425 BUG_ON(0 == me->arch.section[targetsec].stub_entries--);
426
427
a8f44e38 428#ifndef CONFIG_64BIT
1da177e4
LT
429/* for 32-bit the stub looks like this:
430 * ldil L'XXX,%r1
431 * be,n R'XXX(%sr4,%r1)
432 */
433 //value = *(unsigned long *)((value + addend) & ~3); /* why? */
434
435 stub->insns[0] = 0x20200000; /* ldil L'XXX,%r1 */
436 stub->insns[1] = 0xe0202002; /* be,n R'XXX(%sr4,%r1) */
437
438 stub->insns[0] |= reassemble_21(lrsel(value, addend));
439 stub->insns[1] |= reassemble_17(rrsel(value, addend) / 4);
440
441#else
6e1b9585 442/* for 64-bit we have three kinds of stubs:
1da177e4
LT
443 * for normal function calls:
444 * ldd 0(%dp),%dp
445 * ldd 10(%dp), %r1
446 * bve (%r1)
447 * ldd 18(%dp), %dp
448 *
449 * for millicode:
450 * ldil 0, %r1
451 * ldo 0(%r1), %r1
452 * ldd 10(%r1), %r1
453 * bve,n (%r1)
6e1b9585
JB
454 *
455 * for direct branches (jumps between different section of the
456 * same module):
457 * ldil 0, %r1
458 * ldo 0(%r1), %r1
459 * bve,n (%r1)
1da177e4 460 */
6e1b9585
JB
461 switch (stub_type) {
462 case ELF_STUB_GOT:
1da177e4
LT
463 stub->insns[0] = 0x537b0000; /* ldd 0(%dp),%dp */
464 stub->insns[1] = 0x53610020; /* ldd 10(%dp),%r1 */
465 stub->insns[2] = 0xe820d000; /* bve (%r1) */
466 stub->insns[3] = 0x537b0030; /* ldd 18(%dp),%dp */
467
468 stub->insns[0] |= reassemble_14(get_got(me, value, addend) & 0x3fff);
6e1b9585
JB
469 break;
470 case ELF_STUB_MILLI:
1da177e4
LT
471 stub->insns[0] = 0x20200000; /* ldil 0,%r1 */
472 stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */
473 stub->insns[2] = 0x50210020; /* ldd 10(%r1),%r1 */
474 stub->insns[3] = 0xe820d002; /* bve,n (%r1) */
475
476 stub->insns[0] |= reassemble_21(lrsel(value, addend));
477 stub->insns[1] |= reassemble_14(rrsel(value, addend));
6e1b9585
JB
478 break;
479 case ELF_STUB_DIRECT:
480 stub->insns[0] = 0x20200000; /* ldil 0,%r1 */
481 stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */
482 stub->insns[2] = 0xe820d002; /* bve,n (%r1) */
483
484 stub->insns[0] |= reassemble_21(lrsel(value, addend));
485 stub->insns[1] |= reassemble_14(rrsel(value, addend));
486 break;
1da177e4 487 }
6e1b9585 488
1da177e4
LT
489#endif
490
491 return (Elf_Addr)stub;
492}
493
494int apply_relocate(Elf_Shdr *sechdrs,
495 const char *strtab,
496 unsigned int symindex,
497 unsigned int relsec,
498 struct module *me)
499{
500 /* parisc should not need this ... */
501 printk(KERN_ERR "module %s: RELOCATION unsupported\n",
502 me->name);
503 return -ENOEXEC;
504}
505
a8f44e38 506#ifndef CONFIG_64BIT
1da177e4
LT
507int apply_relocate_add(Elf_Shdr *sechdrs,
508 const char *strtab,
509 unsigned int symindex,
510 unsigned int relsec,
511 struct module *me)
512{
513 int i;
514 Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
515 Elf32_Sym *sym;
516 Elf32_Word *loc;
517 Elf32_Addr val;
518 Elf32_Sword addend;
519 Elf32_Addr dot;
c298be74
HD
520 Elf_Addr loc0;
521 unsigned int targetsec = sechdrs[relsec].sh_info;
1da177e4
LT
522 //unsigned long dp = (unsigned long)$global$;
523 register unsigned long dp asm ("r27");
524
525 DEBUGP("Applying relocate section %u to %u\n", relsec,
c298be74 526 targetsec);
1da177e4
LT
527 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
528 /* This is where to make the change */
c298be74 529 loc = (void *)sechdrs[targetsec].sh_addr
1da177e4 530 + rel[i].r_offset;
c298be74
HD
531 /* This is the start of the target section */
532 loc0 = sechdrs[targetsec].sh_addr;
1da177e4
LT
533 /* This is the symbol it is referring to */
534 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
535 + ELF32_R_SYM(rel[i].r_info);
536 if (!sym->st_value) {
537 printk(KERN_WARNING "%s: Unknown symbol %s\n",
538 me->name, strtab + sym->st_name);
539 return -ENOENT;
540 }
541 //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
542 dot = (Elf32_Addr)loc & ~0x03;
543
544 val = sym->st_value;
545 addend = rel[i].r_addend;
546
547#if 0
548#define r(t) ELF32_R_TYPE(rel[i].r_info)==t ? #t :
549 DEBUGP("Symbol %s loc 0x%x val 0x%x addend 0x%x: %s\n",
550 strtab + sym->st_name,
551 (uint32_t)loc, val, addend,
552 r(R_PARISC_PLABEL32)
553 r(R_PARISC_DIR32)
554 r(R_PARISC_DIR21L)
555 r(R_PARISC_DIR14R)
556 r(R_PARISC_SEGREL32)
557 r(R_PARISC_DPREL21L)
558 r(R_PARISC_DPREL14R)
559 r(R_PARISC_PCREL17F)
560 r(R_PARISC_PCREL22F)
561 "UNKNOWN");
562#undef r
563#endif
564
565 switch (ELF32_R_TYPE(rel[i].r_info)) {
566 case R_PARISC_PLABEL32:
567 /* 32-bit function address */
568 /* no function descriptors... */
569 *loc = fsel(val, addend);
570 break;
571 case R_PARISC_DIR32:
572 /* direct 32-bit ref */
573 *loc = fsel(val, addend);
574 break;
575 case R_PARISC_DIR21L:
576 /* left 21 bits of effective address */
577 val = lrsel(val, addend);
578 *loc = mask(*loc, 21) | reassemble_21(val);
579 break;
580 case R_PARISC_DIR14R:
581 /* right 14 bits of effective address */
582 val = rrsel(val, addend);
583 *loc = mask(*loc, 14) | reassemble_14(val);
584 break;
585 case R_PARISC_SEGREL32:
586 /* 32-bit segment relative address */
587 /* See note about special handling of SEGREL32 at
588 * the beginning of this file.
589 */
590 *loc = fsel(val, addend);
591 break;
592 case R_PARISC_DPREL21L:
593 /* left 21 bit of relative address */
594 val = lrsel(val - dp, addend);
595 *loc = mask(*loc, 21) | reassemble_21(val);
596 break;
597 case R_PARISC_DPREL14R:
598 /* right 14 bit of relative address */
599 val = rrsel(val - dp, addend);
600 *loc = mask(*loc, 14) | reassemble_14(val);
601 break;
602 case R_PARISC_PCREL17F:
603 /* 17-bit PC relative address */
c298be74
HD
604 /* calculate direct call offset */
605 val += addend;
1da177e4 606 val = (val - dot - 8)/4;
c298be74
HD
607 if (!RELOC_REACHABLE(val, 17)) {
608 /* direct distance too far, create
609 * stub entry instead */
610 val = get_stub(me, sym->st_value, addend,
611 ELF_STUB_DIRECT, loc0, targetsec);
612 val = (val - dot - 8)/4;
613 CHECK_RELOC(val, 17);
614 }
1da177e4
LT
615 *loc = (*loc & ~0x1f1ffd) | reassemble_17(val);
616 break;
617 case R_PARISC_PCREL22F:
618 /* 22-bit PC relative address; only defined for pa20 */
c298be74
HD
619 /* calculate direct call offset */
620 val += addend;
1da177e4 621 val = (val - dot - 8)/4;
c298be74
HD
622 if (!RELOC_REACHABLE(val, 22)) {
623 /* direct distance too far, create
624 * stub entry instead */
625 val = get_stub(me, sym->st_value, addend,
626 ELF_STUB_DIRECT, loc0, targetsec);
627 val = (val - dot - 8)/4;
628 CHECK_RELOC(val, 22);
629 }
1da177e4
LT
630 *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
631 break;
632
633 default:
634 printk(KERN_ERR "module %s: Unknown relocation: %u\n",
635 me->name, ELF32_R_TYPE(rel[i].r_info));
636 return -ENOEXEC;
637 }
638 }
639
640 return 0;
641}
642
643#else
644int apply_relocate_add(Elf_Shdr *sechdrs,
645 const char *strtab,
646 unsigned int symindex,
647 unsigned int relsec,
648 struct module *me)
649{
650 int i;
651 Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr;
652 Elf64_Sym *sym;
653 Elf64_Word *loc;
654 Elf64_Xword *loc64;
655 Elf64_Addr val;
656 Elf64_Sxword addend;
657 Elf64_Addr dot;
c298be74
HD
658 Elf_Addr loc0;
659 unsigned int targetsec = sechdrs[relsec].sh_info;
1da177e4
LT
660
661 DEBUGP("Applying relocate section %u to %u\n", relsec,
c298be74 662 targetsec);
1da177e4
LT
663 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
664 /* This is where to make the change */
c298be74 665 loc = (void *)sechdrs[targetsec].sh_addr
1da177e4 666 + rel[i].r_offset;
c298be74
HD
667 /* This is the start of the target section */
668 loc0 = sechdrs[targetsec].sh_addr;
1da177e4
LT
669 /* This is the symbol it is referring to */
670 sym = (Elf64_Sym *)sechdrs[symindex].sh_addr
671 + ELF64_R_SYM(rel[i].r_info);
672 if (!sym->st_value) {
673 printk(KERN_WARNING "%s: Unknown symbol %s\n",
674 me->name, strtab + sym->st_name);
675 return -ENOENT;
676 }
677 //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
678 dot = (Elf64_Addr)loc & ~0x03;
679 loc64 = (Elf64_Xword *)loc;
680
681 val = sym->st_value;
682 addend = rel[i].r_addend;
683
684#if 0
685#define r(t) ELF64_R_TYPE(rel[i].r_info)==t ? #t :
686 printk("Symbol %s loc %p val 0x%Lx addend 0x%Lx: %s\n",
687 strtab + sym->st_name,
688 loc, val, addend,
689 r(R_PARISC_LTOFF14R)
690 r(R_PARISC_LTOFF21L)
691 r(R_PARISC_PCREL22F)
692 r(R_PARISC_DIR64)
693 r(R_PARISC_SEGREL32)
694 r(R_PARISC_FPTR64)
695 "UNKNOWN");
696#undef r
697#endif
698
699 switch (ELF64_R_TYPE(rel[i].r_info)) {
700 case R_PARISC_LTOFF21L:
701 /* LT-relative; left 21 bits */
702 val = get_got(me, val, addend);
703 DEBUGP("LTOFF21L Symbol %s loc %p val %lx\n",
704 strtab + sym->st_name,
705 loc, val);
706 val = lrsel(val, 0);
707 *loc = mask(*loc, 21) | reassemble_21(val);
708 break;
709 case R_PARISC_LTOFF14R:
710 /* L(ltoff(val+addend)) */
711 /* LT-relative; right 14 bits */
712 val = get_got(me, val, addend);
713 val = rrsel(val, 0);
714 DEBUGP("LTOFF14R Symbol %s loc %p val %lx\n",
715 strtab + sym->st_name,
716 loc, val);
717 *loc = mask(*loc, 14) | reassemble_14(val);
718 break;
719 case R_PARISC_PCREL22F:
720 /* PC-relative; 22 bits */
721 DEBUGP("PCREL22F Symbol %s loc %p val %lx\n",
722 strtab + sym->st_name,
723 loc, val);
c298be74 724 val += addend;
1da177e4 725 /* can we reach it locally? */
c298be74
HD
726 if (in_local(me, (void *)val)) {
727 /* this is the case where the symbol is local
728 * to the module, but in a different section,
729 * so stub the jump in case it's more than 22
730 * bits away */
731 val = (val - dot - 8)/4;
732 if (!RELOC_REACHABLE(val, 22)) {
733 /* direct distance too far, create
734 * stub entry instead */
735 val = get_stub(me, sym->st_value,
736 addend, ELF_STUB_DIRECT,
737 loc0, targetsec);
738 } else {
739 /* Ok, we can reach it directly. */
740 val = sym->st_value;
741 val += addend;
742 }
743 } else {
744 val = sym->st_value;
745 if (strncmp(strtab + sym->st_name, "$$", 2)
1da177e4 746 == 0)
6e1b9585 747 val = get_stub(me, val, addend, ELF_STUB_MILLI,
c298be74 748 loc0, targetsec);
1da177e4 749 else
6e1b9585 750 val = get_stub(me, val, addend, ELF_STUB_GOT,
c298be74 751 loc0, targetsec);
1da177e4
LT
752 }
753 DEBUGP("STUB FOR %s loc %lx, val %lx+%lx at %lx\n",
754 strtab + sym->st_name, loc, sym->st_value,
755 addend, val);
1da177e4 756 val = (val - dot - 8)/4;
c298be74 757 CHECK_RELOC(val, 22);
1da177e4
LT
758 *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
759 break;
760 case R_PARISC_DIR64:
761 /* 64-bit effective address */
762 *loc64 = val + addend;
763 break;
764 case R_PARISC_SEGREL32:
765 /* 32-bit segment relative address */
766 /* See note about special handling of SEGREL32 at
767 * the beginning of this file.
768 */
769 *loc = fsel(val, addend);
770 break;
771 case R_PARISC_FPTR64:
772 /* 64-bit function address */
959ed340 773 if(in_local(me, (void *)(val + addend))) {
1da177e4
LT
774 *loc64 = get_fdesc(me, val+addend);
775 DEBUGP("FDESC for %s at %p points to %lx\n",
776 strtab + sym->st_name, *loc64,
777 ((Elf_Fdesc *)*loc64)->addr);
778 } else {
779 /* if the symbol is not local to this
780 * module then val+addend is a pointer
781 * to the function descriptor */
782 DEBUGP("Non local FPTR64 Symbol %s loc %p val %lx\n",
783 strtab + sym->st_name,
784 loc, val);
785 *loc64 = val + addend;
786 }
787 break;
788
789 default:
790 printk(KERN_ERR "module %s: Unknown relocation: %Lu\n",
791 me->name, ELF64_R_TYPE(rel[i].r_info));
792 return -ENOEXEC;
793 }
794 }
795 return 0;
796}
797#endif
798
799static void
800register_unwind_table(struct module *me,
801 const Elf_Shdr *sechdrs)
802{
803 unsigned char *table, *end;
804 unsigned long gp;
805
806 if (!me->arch.unwind_section)
807 return;
808
809 table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr;
810 end = table + sechdrs[me->arch.unwind_section].sh_size;
811 gp = (Elf_Addr)me->module_core + me->arch.got_offset;
812
813 DEBUGP("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n",
814 me->arch.unwind_section, table, end, gp);
815 me->arch.unwind = unwind_table_add(me->name, 0, gp, table, end);
816}
817
818static void
819deregister_unwind_table(struct module *me)
820{
821 if (me->arch.unwind)
822 unwind_table_remove(me->arch.unwind);
823}
824
825int module_finalize(const Elf_Ehdr *hdr,
826 const Elf_Shdr *sechdrs,
827 struct module *me)
828{
829 int i;
830 unsigned long nsyms;
831 const char *strtab = NULL;
832 Elf_Sym *newptr, *oldptr;
833 Elf_Shdr *symhdr = NULL;
834#ifdef DEBUG
835 Elf_Fdesc *entry;
836 u32 *addr;
837
838 entry = (Elf_Fdesc *)me->init;
839 printk("FINALIZE, ->init FPTR is %p, GP %lx ADDR %lx\n", entry,
840 entry->gp, entry->addr);
841 addr = (u32 *)entry->addr;
842 printk("INSNS: %x %x %x %x\n",
843 addr[0], addr[1], addr[2], addr[3]);
c298be74 844 printk("got entries used %ld, gots max %ld\n"
1da177e4 845 "fdescs used %ld, fdescs max %ld\n",
1da177e4
LT
846 me->arch.got_count, me->arch.got_max,
847 me->arch.fdesc_count, me->arch.fdesc_max);
848#endif
849
850 register_unwind_table(me, sechdrs);
851
852 /* haven't filled in me->symtab yet, so have to find it
853 * ourselves */
854 for (i = 1; i < hdr->e_shnum; i++) {
855 if(sechdrs[i].sh_type == SHT_SYMTAB
856 && (sechdrs[i].sh_type & SHF_ALLOC)) {
857 int strindex = sechdrs[i].sh_link;
858 /* FIXME: AWFUL HACK
859 * The cast is to drop the const from
860 * the sechdrs pointer */
861 symhdr = (Elf_Shdr *)&sechdrs[i];
862 strtab = (char *)sechdrs[strindex].sh_addr;
863 break;
864 }
865 }
866
867 DEBUGP("module %s: strtab %p, symhdr %p\n",
868 me->name, strtab, symhdr);
869
870 if(me->arch.got_count > MAX_GOTS) {
f8fc18a1
HD
871 printk(KERN_ERR "%s: Global Offset Table overflow (used %ld, allowed %d)\n",
872 me->name, me->arch.got_count, MAX_GOTS);
1da177e4
LT
873 return -EINVAL;
874 }
c298be74
HD
875
876 kfree(me->arch.section);
877 me->arch.section = NULL;
878
1da177e4
LT
879 /* no symbol table */
880 if(symhdr == NULL)
881 return 0;
882
883 oldptr = (void *)symhdr->sh_addr;
884 newptr = oldptr + 1; /* we start counting at 1 */
885 nsyms = symhdr->sh_size / sizeof(Elf_Sym);
886 DEBUGP("OLD num_symtab %lu\n", nsyms);
887
888 for (i = 1; i < nsyms; i++) {
889 oldptr++; /* note, count starts at 1 so preincrement */
890 if(strncmp(strtab + oldptr->st_name,
891 ".L", 2) == 0)
892 continue;
893
894 if(newptr != oldptr)
895 *newptr++ = *oldptr;
896 else
897 newptr++;
898
899 }
900 nsyms = newptr - (Elf_Sym *)symhdr->sh_addr;
901 DEBUGP("NEW num_symtab %lu\n", nsyms);
902 symhdr->sh_size = nsyms * sizeof(Elf_Sym);
6891f8a1 903 return module_bug_finalize(hdr, sechdrs, me);
1da177e4
LT
904}
905
906void module_arch_cleanup(struct module *mod)
907{
908 deregister_unwind_table(mod);
6891f8a1 909 module_bug_cleanup(mod);
1da177e4 910}
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