xref: /openbmc/linux/arch/parisc/kernel/module.c (revision b595076a)
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 #include <linux/slab.h>
65 
66 #include <asm/unwind.h>
67 
68 #if 0
69 #define DEBUGP printk
70 #else
71 #define DEBUGP(fmt...)
72 #endif
73 
74 #define RELOC_REACHABLE(val, bits) \
75 	(( ( !((val) & (1<<((bits)-1))) && ((val)>>(bits)) != 0 )  ||	\
76 	     ( ((val) & (1<<((bits)-1))) && ((val)>>(bits)) != (((__typeof__(val))(~0))>>((bits)+2)))) ? \
77 	0 : 1)
78 
79 #define CHECK_RELOC(val, bits) \
80 	if (!RELOC_REACHABLE(val, bits)) { \
81 		printk(KERN_ERR "module %s relocation of symbol %s is out of range (0x%lx in %d bits)\n", \
82 		me->name, strtab + sym->st_name, (unsigned long)val, bits); \
83 		return -ENOEXEC;			\
84 	}
85 
86 /* Maximum number of GOT entries. We use a long displacement ldd from
87  * the bottom of the table, which has a maximum signed displacement of
88  * 0x3fff; however, since we're only going forward, this becomes
89  * 0x1fff, and thus, since each GOT entry is 8 bytes long we can have
90  * at most 1023 entries.
91  * To overcome this 14bit displacement with some kernel modules, we'll
92  * use instead the unusal 16bit displacement method (see reassemble_16a)
93  * which gives us a maximum positive displacement of 0x7fff, and as such
94  * allows us to allocate up to 4095 GOT entries. */
95 #define MAX_GOTS	4095
96 
97 /* three functions to determine where in the module core
98  * or init pieces the location is */
99 static inline int in_init(struct module *me, void *loc)
100 {
101 	return (loc >= me->module_init &&
102 		loc <= (me->module_init + me->init_size));
103 }
104 
105 static inline int in_core(struct module *me, void *loc)
106 {
107 	return (loc >= me->module_core &&
108 		loc <= (me->module_core + me->core_size));
109 }
110 
111 static inline int in_local(struct module *me, void *loc)
112 {
113 	return in_init(me, loc) || in_core(me, loc);
114 }
115 
116 #ifndef CONFIG_64BIT
117 struct got_entry {
118 	Elf32_Addr addr;
119 };
120 
121 struct stub_entry {
122 	Elf32_Word insns[2]; /* each stub entry has two insns */
123 };
124 #else
125 struct got_entry {
126 	Elf64_Addr addr;
127 };
128 
129 struct stub_entry {
130 	Elf64_Word insns[4]; /* each stub entry has four insns */
131 };
132 #endif
133 
134 /* Field selection types defined by hppa */
135 #define rnd(x)			(((x)+0x1000)&~0x1fff)
136 /* fsel: full 32 bits */
137 #define fsel(v,a)		((v)+(a))
138 /* lsel: select left 21 bits */
139 #define lsel(v,a)		(((v)+(a))>>11)
140 /* rsel: select right 11 bits */
141 #define rsel(v,a)		(((v)+(a))&0x7ff)
142 /* lrsel with rounding of addend to nearest 8k */
143 #define lrsel(v,a)		(((v)+rnd(a))>>11)
144 /* rrsel with rounding of addend to nearest 8k */
145 #define rrsel(v,a)		((((v)+rnd(a))&0x7ff)+((a)-rnd(a)))
146 
147 #define mask(x,sz)		((x) & ~((1<<(sz))-1))
148 
149 
150 /* The reassemble_* functions prepare an immediate value for
151    insertion into an opcode. pa-risc uses all sorts of weird bitfields
152    in the instruction to hold the value.  */
153 static inline int sign_unext(int x, int len)
154 {
155 	int len_ones;
156 
157 	len_ones = (1 << len) - 1;
158 	return x & len_ones;
159 }
160 
161 static inline int low_sign_unext(int x, int len)
162 {
163 	int sign, temp;
164 
165 	sign = (x >> (len-1)) & 1;
166 	temp = sign_unext(x, len-1);
167 	return (temp << 1) | sign;
168 }
169 
170 static inline int reassemble_14(int as14)
171 {
172 	return (((as14 & 0x1fff) << 1) |
173 		((as14 & 0x2000) >> 13));
174 }
175 
176 static inline int reassemble_16a(int as16)
177 {
178 	int s, t;
179 
180 	/* Unusual 16-bit encoding, for wide mode only.  */
181 	t = (as16 << 1) & 0xffff;
182 	s = (as16 & 0x8000);
183 	return (t ^ s ^ (s >> 1)) | (s >> 15);
184 }
185 
186 
187 static inline int reassemble_17(int as17)
188 {
189 	return (((as17 & 0x10000) >> 16) |
190 		((as17 & 0x0f800) << 5) |
191 		((as17 & 0x00400) >> 8) |
192 		((as17 & 0x003ff) << 3));
193 }
194 
195 static inline int reassemble_21(int as21)
196 {
197 	return (((as21 & 0x100000) >> 20) |
198 		((as21 & 0x0ffe00) >> 8) |
199 		((as21 & 0x000180) << 7) |
200 		((as21 & 0x00007c) << 14) |
201 		((as21 & 0x000003) << 12));
202 }
203 
204 static inline int reassemble_22(int as22)
205 {
206 	return (((as22 & 0x200000) >> 21) |
207 		((as22 & 0x1f0000) << 5) |
208 		((as22 & 0x00f800) << 5) |
209 		((as22 & 0x000400) >> 8) |
210 		((as22 & 0x0003ff) << 3));
211 }
212 
213 void *module_alloc(unsigned long size)
214 {
215 	if (size == 0)
216 		return NULL;
217 	return vmalloc(size);
218 }
219 
220 #ifndef CONFIG_64BIT
221 static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
222 {
223 	return 0;
224 }
225 
226 static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
227 {
228 	return 0;
229 }
230 
231 static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
232 {
233 	unsigned long cnt = 0;
234 
235 	for (; n > 0; n--, rela++)
236 	{
237 		switch (ELF32_R_TYPE(rela->r_info)) {
238 			case R_PARISC_PCREL17F:
239 			case R_PARISC_PCREL22F:
240 				cnt++;
241 		}
242 	}
243 
244 	return cnt;
245 }
246 #else
247 static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
248 {
249 	unsigned long cnt = 0;
250 
251 	for (; n > 0; n--, rela++)
252 	{
253 		switch (ELF64_R_TYPE(rela->r_info)) {
254 			case R_PARISC_LTOFF21L:
255 			case R_PARISC_LTOFF14R:
256 			case R_PARISC_PCREL22F:
257 				cnt++;
258 		}
259 	}
260 
261 	return cnt;
262 }
263 
264 static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
265 {
266 	unsigned long cnt = 0;
267 
268 	for (; n > 0; n--, rela++)
269 	{
270 		switch (ELF64_R_TYPE(rela->r_info)) {
271 			case R_PARISC_FPTR64:
272 				cnt++;
273 		}
274 	}
275 
276 	return cnt;
277 }
278 
279 static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
280 {
281 	unsigned long cnt = 0;
282 
283 	for (; n > 0; n--, rela++)
284 	{
285 		switch (ELF64_R_TYPE(rela->r_info)) {
286 			case R_PARISC_PCREL22F:
287 				cnt++;
288 		}
289 	}
290 
291 	return cnt;
292 }
293 #endif
294 
295 
296 /* Free memory returned from module_alloc */
297 void module_free(struct module *mod, void *module_region)
298 {
299 	kfree(mod->arch.section);
300 	mod->arch.section = NULL;
301 
302 	vfree(module_region);
303 }
304 
305 /* Additional bytes needed in front of individual sections */
306 unsigned int arch_mod_section_prepend(struct module *mod,
307 				      unsigned int section)
308 {
309 	/* size needed for all stubs of this section (including
310 	 * one additional for correct alignment of the stubs) */
311 	return (mod->arch.section[section].stub_entries + 1)
312 		* sizeof(struct stub_entry);
313 }
314 
315 #define CONST
316 int module_frob_arch_sections(CONST Elf_Ehdr *hdr,
317 			      CONST Elf_Shdr *sechdrs,
318 			      CONST char *secstrings,
319 			      struct module *me)
320 {
321 	unsigned long gots = 0, fdescs = 0, len;
322 	unsigned int i;
323 
324 	len = hdr->e_shnum * sizeof(me->arch.section[0]);
325 	me->arch.section = kzalloc(len, GFP_KERNEL);
326 	if (!me->arch.section)
327 		return -ENOMEM;
328 
329 	for (i = 1; i < hdr->e_shnum; i++) {
330 		const Elf_Rela *rels = (void *)sechdrs[i].sh_addr;
331 		unsigned long nrels = sechdrs[i].sh_size / sizeof(*rels);
332 		unsigned int count, s;
333 
334 		if (strncmp(secstrings + sechdrs[i].sh_name,
335 			    ".PARISC.unwind", 14) == 0)
336 			me->arch.unwind_section = i;
337 
338 		if (sechdrs[i].sh_type != SHT_RELA)
339 			continue;
340 
341 		/* some of these are not relevant for 32-bit/64-bit
342 		 * we leave them here to make the code common. the
343 		 * compiler will do its thing and optimize out the
344 		 * stuff we don't need
345 		 */
346 		gots += count_gots(rels, nrels);
347 		fdescs += count_fdescs(rels, nrels);
348 
349 		/* XXX: By sorting the relocs and finding duplicate entries
350 		 *  we could reduce the number of necessary stubs and save
351 		 *  some memory. */
352 		count = count_stubs(rels, nrels);
353 		if (!count)
354 			continue;
355 
356 		/* so we need relocation stubs. reserve necessary memory. */
357 		/* sh_info gives the section for which we need to add stubs. */
358 		s = sechdrs[i].sh_info;
359 
360 		/* each code section should only have one relocation section */
361 		WARN_ON(me->arch.section[s].stub_entries);
362 
363 		/* store number of stubs we need for this section */
364 		me->arch.section[s].stub_entries += count;
365 	}
366 
367 	/* align things a bit */
368 	me->core_size = ALIGN(me->core_size, 16);
369 	me->arch.got_offset = me->core_size;
370 	me->core_size += gots * sizeof(struct got_entry);
371 
372 	me->core_size = ALIGN(me->core_size, 16);
373 	me->arch.fdesc_offset = me->core_size;
374 	me->core_size += fdescs * sizeof(Elf_Fdesc);
375 
376 	me->arch.got_max = gots;
377 	me->arch.fdesc_max = fdescs;
378 
379 	return 0;
380 }
381 
382 #ifdef CONFIG_64BIT
383 static Elf64_Word get_got(struct module *me, unsigned long value, long addend)
384 {
385 	unsigned int i;
386 	struct got_entry *got;
387 
388 	value += addend;
389 
390 	BUG_ON(value == 0);
391 
392 	got = me->module_core + me->arch.got_offset;
393 	for (i = 0; got[i].addr; i++)
394 		if (got[i].addr == value)
395 			goto out;
396 
397 	BUG_ON(++me->arch.got_count > me->arch.got_max);
398 
399 	got[i].addr = value;
400  out:
401 	DEBUGP("GOT ENTRY %d[%x] val %lx\n", i, i*sizeof(struct got_entry),
402 	       value);
403 	return i * sizeof(struct got_entry);
404 }
405 #endif /* CONFIG_64BIT */
406 
407 #ifdef CONFIG_64BIT
408 static Elf_Addr get_fdesc(struct module *me, unsigned long value)
409 {
410 	Elf_Fdesc *fdesc = me->module_core + me->arch.fdesc_offset;
411 
412 	if (!value) {
413 		printk(KERN_ERR "%s: zero OPD requested!\n", me->name);
414 		return 0;
415 	}
416 
417 	/* Look for existing fdesc entry. */
418 	while (fdesc->addr) {
419 		if (fdesc->addr == value)
420 			return (Elf_Addr)fdesc;
421 		fdesc++;
422 	}
423 
424 	BUG_ON(++me->arch.fdesc_count > me->arch.fdesc_max);
425 
426 	/* Create new one */
427 	fdesc->addr = value;
428 	fdesc->gp = (Elf_Addr)me->module_core + me->arch.got_offset;
429 	return (Elf_Addr)fdesc;
430 }
431 #endif /* CONFIG_64BIT */
432 
433 enum elf_stub_type {
434 	ELF_STUB_GOT,
435 	ELF_STUB_MILLI,
436 	ELF_STUB_DIRECT,
437 };
438 
439 static Elf_Addr get_stub(struct module *me, unsigned long value, long addend,
440 	enum elf_stub_type stub_type, Elf_Addr loc0, unsigned int targetsec)
441 {
442 	struct stub_entry *stub;
443 	int __maybe_unused d;
444 
445 	/* initialize stub_offset to point in front of the section */
446 	if (!me->arch.section[targetsec].stub_offset) {
447 		loc0 -= (me->arch.section[targetsec].stub_entries + 1) *
448 				sizeof(struct stub_entry);
449 		/* get correct alignment for the stubs */
450 		loc0 = ALIGN(loc0, sizeof(struct stub_entry));
451 		me->arch.section[targetsec].stub_offset = loc0;
452 	}
453 
454 	/* get address of stub entry */
455 	stub = (void *) me->arch.section[targetsec].stub_offset;
456 	me->arch.section[targetsec].stub_offset += sizeof(struct stub_entry);
457 
458 	/* do not write outside available stub area */
459 	BUG_ON(0 == me->arch.section[targetsec].stub_entries--);
460 
461 
462 #ifndef CONFIG_64BIT
463 /* for 32-bit the stub looks like this:
464  * 	ldil L'XXX,%r1
465  * 	be,n R'XXX(%sr4,%r1)
466  */
467 	//value = *(unsigned long *)((value + addend) & ~3); /* why? */
468 
469 	stub->insns[0] = 0x20200000;	/* ldil L'XXX,%r1	*/
470 	stub->insns[1] = 0xe0202002;	/* be,n R'XXX(%sr4,%r1)	*/
471 
472 	stub->insns[0] |= reassemble_21(lrsel(value, addend));
473 	stub->insns[1] |= reassemble_17(rrsel(value, addend) / 4);
474 
475 #else
476 /* for 64-bit we have three kinds of stubs:
477  * for normal function calls:
478  * 	ldd 0(%dp),%dp
479  * 	ldd 10(%dp), %r1
480  * 	bve (%r1)
481  * 	ldd 18(%dp), %dp
482  *
483  * for millicode:
484  * 	ldil 0, %r1
485  * 	ldo 0(%r1), %r1
486  * 	ldd 10(%r1), %r1
487  * 	bve,n (%r1)
488  *
489  * for direct branches (jumps between different section of the
490  * same module):
491  *	ldil 0, %r1
492  *	ldo 0(%r1), %r1
493  *	bve,n (%r1)
494  */
495 	switch (stub_type) {
496 	case ELF_STUB_GOT:
497 		d = get_got(me, value, addend);
498 		if (d <= 15) {
499 			/* Format 5 */
500 			stub->insns[0] = 0x0f6010db; /* ldd 0(%dp),%dp	*/
501 			stub->insns[0] |= low_sign_unext(d, 5) << 16;
502 		} else {
503 			/* Format 3 */
504 			stub->insns[0] = 0x537b0000; /* ldd 0(%dp),%dp	*/
505 			stub->insns[0] |= reassemble_16a(d);
506 		}
507 		stub->insns[1] = 0x53610020;	/* ldd 10(%dp),%r1	*/
508 		stub->insns[2] = 0xe820d000;	/* bve (%r1)		*/
509 		stub->insns[3] = 0x537b0030;	/* ldd 18(%dp),%dp	*/
510 		break;
511 	case ELF_STUB_MILLI:
512 		stub->insns[0] = 0x20200000;	/* ldil 0,%r1		*/
513 		stub->insns[1] = 0x34210000;	/* ldo 0(%r1), %r1	*/
514 		stub->insns[2] = 0x50210020;	/* ldd 10(%r1),%r1	*/
515 		stub->insns[3] = 0xe820d002;	/* bve,n (%r1)		*/
516 
517 		stub->insns[0] |= reassemble_21(lrsel(value, addend));
518 		stub->insns[1] |= reassemble_14(rrsel(value, addend));
519 		break;
520 	case ELF_STUB_DIRECT:
521 		stub->insns[0] = 0x20200000;    /* ldil 0,%r1           */
522 		stub->insns[1] = 0x34210000;    /* ldo 0(%r1), %r1      */
523 		stub->insns[2] = 0xe820d002;    /* bve,n (%r1)          */
524 
525 		stub->insns[0] |= reassemble_21(lrsel(value, addend));
526 		stub->insns[1] |= reassemble_14(rrsel(value, addend));
527 		break;
528 	}
529 
530 #endif
531 
532 	return (Elf_Addr)stub;
533 }
534 
535 int apply_relocate(Elf_Shdr *sechdrs,
536 		   const char *strtab,
537 		   unsigned int symindex,
538 		   unsigned int relsec,
539 		   struct module *me)
540 {
541 	/* parisc should not need this ... */
542 	printk(KERN_ERR "module %s: RELOCATION unsupported\n",
543 	       me->name);
544 	return -ENOEXEC;
545 }
546 
547 #ifndef CONFIG_64BIT
548 int apply_relocate_add(Elf_Shdr *sechdrs,
549 		       const char *strtab,
550 		       unsigned int symindex,
551 		       unsigned int relsec,
552 		       struct module *me)
553 {
554 	int i;
555 	Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
556 	Elf32_Sym *sym;
557 	Elf32_Word *loc;
558 	Elf32_Addr val;
559 	Elf32_Sword addend;
560 	Elf32_Addr dot;
561 	Elf_Addr loc0;
562 	unsigned int targetsec = sechdrs[relsec].sh_info;
563 	//unsigned long dp = (unsigned long)$global$;
564 	register unsigned long dp asm ("r27");
565 
566 	DEBUGP("Applying relocate section %u to %u\n", relsec,
567 	       targetsec);
568 	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
569 		/* This is where to make the change */
570 		loc = (void *)sechdrs[targetsec].sh_addr
571 		      + rel[i].r_offset;
572 		/* This is the start of the target section */
573 		loc0 = sechdrs[targetsec].sh_addr;
574 		/* This is the symbol it is referring to */
575 		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
576 			+ ELF32_R_SYM(rel[i].r_info);
577 		if (!sym->st_value) {
578 			printk(KERN_WARNING "%s: Unknown symbol %s\n",
579 			       me->name, strtab + sym->st_name);
580 			return -ENOENT;
581 		}
582 		//dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
583 		dot =  (Elf32_Addr)loc & ~0x03;
584 
585 		val = sym->st_value;
586 		addend = rel[i].r_addend;
587 
588 #if 0
589 #define r(t) ELF32_R_TYPE(rel[i].r_info)==t ? #t :
590 		DEBUGP("Symbol %s loc 0x%x val 0x%x addend 0x%x: %s\n",
591 			strtab + sym->st_name,
592 			(uint32_t)loc, val, addend,
593 			r(R_PARISC_PLABEL32)
594 			r(R_PARISC_DIR32)
595 			r(R_PARISC_DIR21L)
596 			r(R_PARISC_DIR14R)
597 			r(R_PARISC_SEGREL32)
598 			r(R_PARISC_DPREL21L)
599 			r(R_PARISC_DPREL14R)
600 			r(R_PARISC_PCREL17F)
601 			r(R_PARISC_PCREL22F)
602 			"UNKNOWN");
603 #undef r
604 #endif
605 
606 		switch (ELF32_R_TYPE(rel[i].r_info)) {
607 		case R_PARISC_PLABEL32:
608 			/* 32-bit function address */
609 			/* no function descriptors... */
610 			*loc = fsel(val, addend);
611 			break;
612 		case R_PARISC_DIR32:
613 			/* direct 32-bit ref */
614 			*loc = fsel(val, addend);
615 			break;
616 		case R_PARISC_DIR21L:
617 			/* left 21 bits of effective address */
618 			val = lrsel(val, addend);
619 			*loc = mask(*loc, 21) | reassemble_21(val);
620 			break;
621 		case R_PARISC_DIR14R:
622 			/* right 14 bits of effective address */
623 			val = rrsel(val, addend);
624 			*loc = mask(*loc, 14) | reassemble_14(val);
625 			break;
626 		case R_PARISC_SEGREL32:
627 			/* 32-bit segment relative address */
628 			/* See note about special handling of SEGREL32 at
629 			 * the beginning of this file.
630 			 */
631 			*loc = fsel(val, addend);
632 			break;
633 		case R_PARISC_DPREL21L:
634 			/* left 21 bit of relative address */
635 			val = lrsel(val - dp, addend);
636 			*loc = mask(*loc, 21) | reassemble_21(val);
637 			break;
638 		case R_PARISC_DPREL14R:
639 			/* right 14 bit of relative address */
640 			val = rrsel(val - dp, addend);
641 			*loc = mask(*loc, 14) | reassemble_14(val);
642 			break;
643 		case R_PARISC_PCREL17F:
644 			/* 17-bit PC relative address */
645 			/* calculate direct call offset */
646 			val += addend;
647 			val = (val - dot - 8)/4;
648 			if (!RELOC_REACHABLE(val, 17)) {
649 				/* direct distance too far, create
650 				 * stub entry instead */
651 				val = get_stub(me, sym->st_value, addend,
652 					ELF_STUB_DIRECT, loc0, targetsec);
653 				val = (val - dot - 8)/4;
654 				CHECK_RELOC(val, 17);
655 			}
656 			*loc = (*loc & ~0x1f1ffd) | reassemble_17(val);
657 			break;
658 		case R_PARISC_PCREL22F:
659 			/* 22-bit PC relative address; only defined for pa20 */
660 			/* calculate direct call offset */
661 			val += addend;
662 			val = (val - dot - 8)/4;
663 			if (!RELOC_REACHABLE(val, 22)) {
664 				/* direct distance too far, create
665 				 * stub entry instead */
666 				val = get_stub(me, sym->st_value, addend,
667 					ELF_STUB_DIRECT, loc0, targetsec);
668 				val = (val - dot - 8)/4;
669 				CHECK_RELOC(val, 22);
670 			}
671 			*loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
672 			break;
673 
674 		default:
675 			printk(KERN_ERR "module %s: Unknown relocation: %u\n",
676 			       me->name, ELF32_R_TYPE(rel[i].r_info));
677 			return -ENOEXEC;
678 		}
679 	}
680 
681 	return 0;
682 }
683 
684 #else
685 int apply_relocate_add(Elf_Shdr *sechdrs,
686 		       const char *strtab,
687 		       unsigned int symindex,
688 		       unsigned int relsec,
689 		       struct module *me)
690 {
691 	int i;
692 	Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr;
693 	Elf64_Sym *sym;
694 	Elf64_Word *loc;
695 	Elf64_Xword *loc64;
696 	Elf64_Addr val;
697 	Elf64_Sxword addend;
698 	Elf64_Addr dot;
699 	Elf_Addr loc0;
700 	unsigned int targetsec = sechdrs[relsec].sh_info;
701 
702 	DEBUGP("Applying relocate section %u to %u\n", relsec,
703 	       targetsec);
704 	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
705 		/* This is where to make the change */
706 		loc = (void *)sechdrs[targetsec].sh_addr
707 		      + rel[i].r_offset;
708 		/* This is the start of the target section */
709 		loc0 = sechdrs[targetsec].sh_addr;
710 		/* This is the symbol it is referring to */
711 		sym = (Elf64_Sym *)sechdrs[symindex].sh_addr
712 			+ ELF64_R_SYM(rel[i].r_info);
713 		if (!sym->st_value) {
714 			printk(KERN_WARNING "%s: Unknown symbol %s\n",
715 			       me->name, strtab + sym->st_name);
716 			return -ENOENT;
717 		}
718 		//dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
719 		dot = (Elf64_Addr)loc & ~0x03;
720 		loc64 = (Elf64_Xword *)loc;
721 
722 		val = sym->st_value;
723 		addend = rel[i].r_addend;
724 
725 #if 0
726 #define r(t) ELF64_R_TYPE(rel[i].r_info)==t ? #t :
727 		printk("Symbol %s loc %p val 0x%Lx addend 0x%Lx: %s\n",
728 			strtab + sym->st_name,
729 			loc, val, addend,
730 			r(R_PARISC_LTOFF14R)
731 			r(R_PARISC_LTOFF21L)
732 			r(R_PARISC_PCREL22F)
733 			r(R_PARISC_DIR64)
734 			r(R_PARISC_SEGREL32)
735 			r(R_PARISC_FPTR64)
736 			"UNKNOWN");
737 #undef r
738 #endif
739 
740 		switch (ELF64_R_TYPE(rel[i].r_info)) {
741 		case R_PARISC_LTOFF21L:
742 			/* LT-relative; left 21 bits */
743 			val = get_got(me, val, addend);
744 			DEBUGP("LTOFF21L Symbol %s loc %p val %lx\n",
745 			       strtab + sym->st_name,
746 			       loc, val);
747 			val = lrsel(val, 0);
748 			*loc = mask(*loc, 21) | reassemble_21(val);
749 			break;
750 		case R_PARISC_LTOFF14R:
751 			/* L(ltoff(val+addend)) */
752 			/* LT-relative; right 14 bits */
753 			val = get_got(me, val, addend);
754 			val = rrsel(val, 0);
755 			DEBUGP("LTOFF14R Symbol %s loc %p val %lx\n",
756 			       strtab + sym->st_name,
757 			       loc, val);
758 			*loc = mask(*loc, 14) | reassemble_14(val);
759 			break;
760 		case R_PARISC_PCREL22F:
761 			/* PC-relative; 22 bits */
762 			DEBUGP("PCREL22F Symbol %s loc %p val %lx\n",
763 			       strtab + sym->st_name,
764 			       loc, val);
765 			val += addend;
766 			/* can we reach it locally? */
767 			if (in_local(me, (void *)val)) {
768 				/* this is the case where the symbol is local
769 				 * to the module, but in a different section,
770 				 * so stub the jump in case it's more than 22
771 				 * bits away */
772 				val = (val - dot - 8)/4;
773 				if (!RELOC_REACHABLE(val, 22)) {
774 					/* direct distance too far, create
775 					 * stub entry instead */
776 					val = get_stub(me, sym->st_value,
777 						addend, ELF_STUB_DIRECT,
778 						loc0, targetsec);
779 				} else {
780 					/* Ok, we can reach it directly. */
781 					val = sym->st_value;
782 					val += addend;
783 				}
784 			} else {
785 				val = sym->st_value;
786 				if (strncmp(strtab + sym->st_name, "$$", 2)
787 				    == 0)
788 					val = get_stub(me, val, addend, ELF_STUB_MILLI,
789 						       loc0, targetsec);
790 				else
791 					val = get_stub(me, val, addend, ELF_STUB_GOT,
792 						       loc0, targetsec);
793 			}
794 			DEBUGP("STUB FOR %s loc %lx, val %lx+%lx at %lx\n",
795 			       strtab + sym->st_name, loc, sym->st_value,
796 			       addend, val);
797 			val = (val - dot - 8)/4;
798 			CHECK_RELOC(val, 22);
799 			*loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
800 			break;
801 		case R_PARISC_DIR64:
802 			/* 64-bit effective address */
803 			*loc64 = val + addend;
804 			break;
805 		case R_PARISC_SEGREL32:
806 			/* 32-bit segment relative address */
807 			/* See note about special handling of SEGREL32 at
808 			 * the beginning of this file.
809 			 */
810 			*loc = fsel(val, addend);
811 			break;
812 		case R_PARISC_FPTR64:
813 			/* 64-bit function address */
814 			if(in_local(me, (void *)(val + addend))) {
815 				*loc64 = get_fdesc(me, val+addend);
816 				DEBUGP("FDESC for %s at %p points to %lx\n",
817 				       strtab + sym->st_name, *loc64,
818 				       ((Elf_Fdesc *)*loc64)->addr);
819 			} else {
820 				/* if the symbol is not local to this
821 				 * module then val+addend is a pointer
822 				 * to the function descriptor */
823 				DEBUGP("Non local FPTR64 Symbol %s loc %p val %lx\n",
824 				       strtab + sym->st_name,
825 				       loc, val);
826 				*loc64 = val + addend;
827 			}
828 			break;
829 
830 		default:
831 			printk(KERN_ERR "module %s: Unknown relocation: %Lu\n",
832 			       me->name, ELF64_R_TYPE(rel[i].r_info));
833 			return -ENOEXEC;
834 		}
835 	}
836 	return 0;
837 }
838 #endif
839 
840 static void
841 register_unwind_table(struct module *me,
842 		      const Elf_Shdr *sechdrs)
843 {
844 	unsigned char *table, *end;
845 	unsigned long gp;
846 
847 	if (!me->arch.unwind_section)
848 		return;
849 
850 	table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr;
851 	end = table + sechdrs[me->arch.unwind_section].sh_size;
852 	gp = (Elf_Addr)me->module_core + me->arch.got_offset;
853 
854 	DEBUGP("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n",
855 	       me->arch.unwind_section, table, end, gp);
856 	me->arch.unwind = unwind_table_add(me->name, 0, gp, table, end);
857 }
858 
859 static void
860 deregister_unwind_table(struct module *me)
861 {
862 	if (me->arch.unwind)
863 		unwind_table_remove(me->arch.unwind);
864 }
865 
866 int module_finalize(const Elf_Ehdr *hdr,
867 		    const Elf_Shdr *sechdrs,
868 		    struct module *me)
869 {
870 	int i;
871 	unsigned long nsyms;
872 	const char *strtab = NULL;
873 	Elf_Sym *newptr, *oldptr;
874 	Elf_Shdr *symhdr = NULL;
875 #ifdef DEBUG
876 	Elf_Fdesc *entry;
877 	u32 *addr;
878 
879 	entry = (Elf_Fdesc *)me->init;
880 	printk("FINALIZE, ->init FPTR is %p, GP %lx ADDR %lx\n", entry,
881 	       entry->gp, entry->addr);
882 	addr = (u32 *)entry->addr;
883 	printk("INSNS: %x %x %x %x\n",
884 	       addr[0], addr[1], addr[2], addr[3]);
885 	printk("got entries used %ld, gots max %ld\n"
886 	       "fdescs used %ld, fdescs max %ld\n",
887 	       me->arch.got_count, me->arch.got_max,
888 	       me->arch.fdesc_count, me->arch.fdesc_max);
889 #endif
890 
891 	register_unwind_table(me, sechdrs);
892 
893 	/* haven't filled in me->symtab yet, so have to find it
894 	 * ourselves */
895 	for (i = 1; i < hdr->e_shnum; i++) {
896 		if(sechdrs[i].sh_type == SHT_SYMTAB
897 		   && (sechdrs[i].sh_flags & SHF_ALLOC)) {
898 			int strindex = sechdrs[i].sh_link;
899 			/* FIXME: AWFUL HACK
900 			 * The cast is to drop the const from
901 			 * the sechdrs pointer */
902 			symhdr = (Elf_Shdr *)&sechdrs[i];
903 			strtab = (char *)sechdrs[strindex].sh_addr;
904 			break;
905 		}
906 	}
907 
908 	DEBUGP("module %s: strtab %p, symhdr %p\n",
909 	       me->name, strtab, symhdr);
910 
911 	if(me->arch.got_count > MAX_GOTS) {
912 		printk(KERN_ERR "%s: Global Offset Table overflow (used %ld, allowed %d)\n",
913 				me->name, me->arch.got_count, MAX_GOTS);
914 		return -EINVAL;
915 	}
916 
917 	kfree(me->arch.section);
918 	me->arch.section = NULL;
919 
920 	/* no symbol table */
921 	if(symhdr == NULL)
922 		return 0;
923 
924 	oldptr = (void *)symhdr->sh_addr;
925 	newptr = oldptr + 1;	/* we start counting at 1 */
926 	nsyms = symhdr->sh_size / sizeof(Elf_Sym);
927 	DEBUGP("OLD num_symtab %lu\n", nsyms);
928 
929 	for (i = 1; i < nsyms; i++) {
930 		oldptr++;	/* note, count starts at 1 so preincrement */
931 		if(strncmp(strtab + oldptr->st_name,
932 			      ".L", 2) == 0)
933 			continue;
934 
935 		if(newptr != oldptr)
936 			*newptr++ = *oldptr;
937 		else
938 			newptr++;
939 
940 	}
941 	nsyms = newptr - (Elf_Sym *)symhdr->sh_addr;
942 	DEBUGP("NEW num_symtab %lu\n", nsyms);
943 	symhdr->sh_size = nsyms * sizeof(Elf_Sym);
944 	return 0;
945 }
946 
947 void module_arch_cleanup(struct module *mod)
948 {
949 	deregister_unwind_table(mod);
950 }
951