xref: /linux/arch/parisc/kernel/module.c (revision 5bdef865eb358b6f3760e25e591ae115e9eeddef)
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>
9  *    Copyright (C) 2008 Helge Deller <deller@gmx.de>
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:
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  *
41  *    - SEGREL32 handling
42  *      We are not doing SEGREL32 handling correctly. According to the ABI, we
43  *      should do a value offset, like this:
44  *			if (in_init(me, (void *)val))
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>
63 #include <linux/bug.h>
64 
65 #include <asm/unwind.h>
66 
67 #if 0
68 #define DEBUGP printk
69 #else
70 #define DEBUGP(fmt...)
71 #endif
72 
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 
78 #define CHECK_RELOC(val, bits) \
79 	if (!RELOC_REACHABLE(val, bits)) { \
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 */
94 static inline int in_init(struct module *me, void *loc)
95 {
96 	return (loc >= me->module_init &&
97 		loc <= (me->module_init + me->init_size));
98 }
99 
100 static inline int in_core(struct module *me, void *loc)
101 {
102 	return (loc >= me->module_core &&
103 		loc <= (me->module_core + me->core_size));
104 }
105 
106 static inline int in_local(struct module *me, void *loc)
107 {
108 	return in_init(me, loc) || in_core(me, loc);
109 }
110 
111 #ifndef CONFIG_64BIT
112 struct got_entry {
113 	Elf32_Addr addr;
114 };
115 
116 struct stub_entry {
117 	Elf32_Word insns[2]; /* each stub entry has two insns */
118 };
119 #else
120 struct got_entry {
121 	Elf64_Addr addr;
122 };
123 
124 struct 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.  */
148 static inline int reassemble_14(int as14)
149 {
150 	return (((as14 & 0x1fff) << 1) |
151 		((as14 & 0x2000) >> 13));
152 }
153 
154 static 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 
162 static 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 
171 static 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 
180 void *module_alloc(unsigned long size)
181 {
182 	if (size == 0)
183 		return NULL;
184 	return vmalloc(size);
185 }
186 
187 #ifndef CONFIG_64BIT
188 static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
189 {
190 	return 0;
191 }
192 
193 static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
194 {
195 	return 0;
196 }
197 
198 static 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
214 static 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 
231 static 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 
246 static 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 */
264 void module_free(struct module *mod, void *module_region)
265 {
266 	kfree(mod->arch.section);
267 	mod->arch.section = NULL;
268 
269 	vfree(module_region);
270 }
271 
272 /* Additional bytes needed in front of individual sections */
273 unsigned 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 
282 #define CONST
283 int module_frob_arch_sections(CONST Elf_Ehdr *hdr,
284 			      CONST Elf_Shdr *sechdrs,
285 			      CONST char *secstrings,
286 			      struct module *me)
287 {
288 	unsigned long gots = 0, fdescs = 0, len;
289 	unsigned int i;
290 
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 
296 	for (i = 1; i < hdr->e_shnum; i++) {
297 		const Elf_Rela *rels = (void *)sechdrs[i].sh_addr;
298 		unsigned long nrels = sechdrs[i].sh_size / sizeof(*rels);
299 		unsigned int count, s;
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);
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;
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 
343 	me->arch.got_max = gots;
344 	me->arch.fdesc_max = fdescs;
345 
346 	return 0;
347 }
348 
349 #ifdef CONFIG_64BIT
350 static 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 }
372 #endif /* CONFIG_64BIT */
373 
374 #ifdef CONFIG_64BIT
375 static 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 }
398 #endif /* CONFIG_64BIT */
399 
400 enum elf_stub_type {
401 	ELF_STUB_GOT,
402 	ELF_STUB_MILLI,
403 	ELF_STUB_DIRECT,
404 };
405 
406 static Elf_Addr get_stub(struct module *me, unsigned long value, long addend,
407 	enum elf_stub_type stub_type, Elf_Addr loc0, unsigned int targetsec)
408 {
409 	struct stub_entry *stub;
410 
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;
418 	}
419 
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 
428 #ifndef CONFIG_64BIT
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
442 /* for 64-bit we have three kinds of stubs:
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)
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)
460  */
461 	switch (stub_type) {
462 	case ELF_STUB_GOT:
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);
469 		break;
470 	case ELF_STUB_MILLI:
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));
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;
487 	}
488 
489 #endif
490 
491 	return (Elf_Addr)stub;
492 }
493 
494 int 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 
506 #ifndef CONFIG_64BIT
507 int 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;
520 	Elf_Addr loc0;
521 	unsigned int targetsec = sechdrs[relsec].sh_info;
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,
526 	       targetsec);
527 	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
528 		/* This is where to make the change */
529 		loc = (void *)sechdrs[targetsec].sh_addr
530 		      + rel[i].r_offset;
531 		/* This is the start of the target section */
532 		loc0 = sechdrs[targetsec].sh_addr;
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 */
604 			/* calculate direct call offset */
605 			val += addend;
606 			val = (val - dot - 8)/4;
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 			}
615 			*loc = (*loc & ~0x1f1ffd) | reassemble_17(val);
616 			break;
617 		case R_PARISC_PCREL22F:
618 			/* 22-bit PC relative address; only defined for pa20 */
619 			/* calculate direct call offset */
620 			val += addend;
621 			val = (val - dot - 8)/4;
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 			}
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
644 int 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;
658 	Elf_Addr loc0;
659 	unsigned int targetsec = sechdrs[relsec].sh_info;
660 
661 	DEBUGP("Applying relocate section %u to %u\n", relsec,
662 	       targetsec);
663 	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
664 		/* This is where to make the change */
665 		loc = (void *)sechdrs[targetsec].sh_addr
666 		      + rel[i].r_offset;
667 		/* This is the start of the target section */
668 		loc0 = sechdrs[targetsec].sh_addr;
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);
724 			val += addend;
725 			/* can we reach it locally? */
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)
746 				    == 0)
747 					val = get_stub(me, val, addend, ELF_STUB_MILLI,
748 						       loc0, targetsec);
749 				else
750 					val = get_stub(me, val, addend, ELF_STUB_GOT,
751 						       loc0, targetsec);
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);
756 			val = (val - dot - 8)/4;
757 			CHECK_RELOC(val, 22);
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 */
773 			if(in_local(me, (void *)(val + addend))) {
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 
799 static void
800 register_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 
818 static void
819 deregister_unwind_table(struct module *me)
820 {
821 	if (me->arch.unwind)
822 		unwind_table_remove(me->arch.unwind);
823 }
824 
825 int 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]);
844 	printk("got entries used %ld, gots max %ld\n"
845 	       "fdescs used %ld, fdescs max %ld\n",
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) {
871 		printk(KERN_ERR "%s: Global Offset Table overflow (used %ld, allowed %d)\n",
872 				me->name, me->arch.got_count, MAX_GOTS);
873 		return -EINVAL;
874 	}
875 
876 	kfree(me->arch.section);
877 	me->arch.section = NULL;
878 
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);
903 	return module_bug_finalize(hdr, sechdrs, me);
904 }
905 
906 void module_arch_cleanup(struct module *mod)
907 {
908 	deregister_unwind_table(mod);
909 	module_bug_cleanup(mod);
910 }
911