xref: /openbmc/linux/arch/parisc/kernel/module.c (revision 930beb5a)
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/mm.h>
65 #include <linux/slab.h>
66 
67 #include <asm/pgtable.h>
68 #include <asm/unwind.h>
69 
70 #if 0
71 #define DEBUGP printk
72 #else
73 #define DEBUGP(fmt...)
74 #endif
75 
76 #define RELOC_REACHABLE(val, bits) \
77 	(( ( !((val) & (1<<((bits)-1))) && ((val)>>(bits)) != 0 )  ||	\
78 	     ( ((val) & (1<<((bits)-1))) && ((val)>>(bits)) != (((__typeof__(val))(~0))>>((bits)+2)))) ? \
79 	0 : 1)
80 
81 #define CHECK_RELOC(val, bits) \
82 	if (!RELOC_REACHABLE(val, bits)) { \
83 		printk(KERN_ERR "module %s relocation of symbol %s is out of range (0x%lx in %d bits)\n", \
84 		me->name, strtab + sym->st_name, (unsigned long)val, bits); \
85 		return -ENOEXEC;			\
86 	}
87 
88 /* Maximum number of GOT entries. We use a long displacement ldd from
89  * the bottom of the table, which has a maximum signed displacement of
90  * 0x3fff; however, since we're only going forward, this becomes
91  * 0x1fff, and thus, since each GOT entry is 8 bytes long we can have
92  * at most 1023 entries.
93  * To overcome this 14bit displacement with some kernel modules, we'll
94  * use instead the unusal 16bit displacement method (see reassemble_16a)
95  * which gives us a maximum positive displacement of 0x7fff, and as such
96  * allows us to allocate up to 4095 GOT entries. */
97 #define MAX_GOTS	4095
98 
99 /* three functions to determine where in the module core
100  * or init pieces the location is */
101 static inline int in_init(struct module *me, void *loc)
102 {
103 	return (loc >= me->module_init &&
104 		loc <= (me->module_init + me->init_size));
105 }
106 
107 static inline int in_core(struct module *me, void *loc)
108 {
109 	return (loc >= me->module_core &&
110 		loc <= (me->module_core + me->core_size));
111 }
112 
113 static inline int in_local(struct module *me, void *loc)
114 {
115 	return in_init(me, loc) || in_core(me, loc);
116 }
117 
118 #ifndef CONFIG_64BIT
119 struct got_entry {
120 	Elf32_Addr addr;
121 };
122 
123 struct stub_entry {
124 	Elf32_Word insns[2]; /* each stub entry has two insns */
125 };
126 #else
127 struct got_entry {
128 	Elf64_Addr addr;
129 };
130 
131 struct stub_entry {
132 	Elf64_Word insns[4]; /* each stub entry has four insns */
133 };
134 #endif
135 
136 /* Field selection types defined by hppa */
137 #define rnd(x)			(((x)+0x1000)&~0x1fff)
138 /* fsel: full 32 bits */
139 #define fsel(v,a)		((v)+(a))
140 /* lsel: select left 21 bits */
141 #define lsel(v,a)		(((v)+(a))>>11)
142 /* rsel: select right 11 bits */
143 #define rsel(v,a)		(((v)+(a))&0x7ff)
144 /* lrsel with rounding of addend to nearest 8k */
145 #define lrsel(v,a)		(((v)+rnd(a))>>11)
146 /* rrsel with rounding of addend to nearest 8k */
147 #define rrsel(v,a)		((((v)+rnd(a))&0x7ff)+((a)-rnd(a)))
148 
149 #define mask(x,sz)		((x) & ~((1<<(sz))-1))
150 
151 
152 /* The reassemble_* functions prepare an immediate value for
153    insertion into an opcode. pa-risc uses all sorts of weird bitfields
154    in the instruction to hold the value.  */
155 static inline int sign_unext(int x, int len)
156 {
157 	int len_ones;
158 
159 	len_ones = (1 << len) - 1;
160 	return x & len_ones;
161 }
162 
163 static inline int low_sign_unext(int x, int len)
164 {
165 	int sign, temp;
166 
167 	sign = (x >> (len-1)) & 1;
168 	temp = sign_unext(x, len-1);
169 	return (temp << 1) | sign;
170 }
171 
172 static inline int reassemble_14(int as14)
173 {
174 	return (((as14 & 0x1fff) << 1) |
175 		((as14 & 0x2000) >> 13));
176 }
177 
178 static inline int reassemble_16a(int as16)
179 {
180 	int s, t;
181 
182 	/* Unusual 16-bit encoding, for wide mode only.  */
183 	t = (as16 << 1) & 0xffff;
184 	s = (as16 & 0x8000);
185 	return (t ^ s ^ (s >> 1)) | (s >> 15);
186 }
187 
188 
189 static inline int reassemble_17(int as17)
190 {
191 	return (((as17 & 0x10000) >> 16) |
192 		((as17 & 0x0f800) << 5) |
193 		((as17 & 0x00400) >> 8) |
194 		((as17 & 0x003ff) << 3));
195 }
196 
197 static inline int reassemble_21(int as21)
198 {
199 	return (((as21 & 0x100000) >> 20) |
200 		((as21 & 0x0ffe00) >> 8) |
201 		((as21 & 0x000180) << 7) |
202 		((as21 & 0x00007c) << 14) |
203 		((as21 & 0x000003) << 12));
204 }
205 
206 static inline int reassemble_22(int as22)
207 {
208 	return (((as22 & 0x200000) >> 21) |
209 		((as22 & 0x1f0000) << 5) |
210 		((as22 & 0x00f800) << 5) |
211 		((as22 & 0x000400) >> 8) |
212 		((as22 & 0x0003ff) << 3));
213 }
214 
215 void *module_alloc(unsigned long size)
216 {
217 	/* using RWX means less protection for modules, but it's
218 	 * easier than trying to map the text, data, init_text and
219 	 * init_data correctly */
220 	return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
221 				    GFP_KERNEL | __GFP_HIGHMEM,
222 				    PAGE_KERNEL_RWX, NUMA_NO_NODE,
223 				    __builtin_return_address(0));
224 }
225 
226 #ifndef CONFIG_64BIT
227 static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
228 {
229 	return 0;
230 }
231 
232 static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
233 {
234 	return 0;
235 }
236 
237 static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
238 {
239 	unsigned long cnt = 0;
240 
241 	for (; n > 0; n--, rela++)
242 	{
243 		switch (ELF32_R_TYPE(rela->r_info)) {
244 			case R_PARISC_PCREL17F:
245 			case R_PARISC_PCREL22F:
246 				cnt++;
247 		}
248 	}
249 
250 	return cnt;
251 }
252 #else
253 static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
254 {
255 	unsigned long cnt = 0;
256 
257 	for (; n > 0; n--, rela++)
258 	{
259 		switch (ELF64_R_TYPE(rela->r_info)) {
260 			case R_PARISC_LTOFF21L:
261 			case R_PARISC_LTOFF14R:
262 			case R_PARISC_PCREL22F:
263 				cnt++;
264 		}
265 	}
266 
267 	return cnt;
268 }
269 
270 static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
271 {
272 	unsigned long cnt = 0;
273 
274 	for (; n > 0; n--, rela++)
275 	{
276 		switch (ELF64_R_TYPE(rela->r_info)) {
277 			case R_PARISC_FPTR64:
278 				cnt++;
279 		}
280 	}
281 
282 	return cnt;
283 }
284 
285 static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
286 {
287 	unsigned long cnt = 0;
288 
289 	for (; n > 0; n--, rela++)
290 	{
291 		switch (ELF64_R_TYPE(rela->r_info)) {
292 			case R_PARISC_PCREL22F:
293 				cnt++;
294 		}
295 	}
296 
297 	return cnt;
298 }
299 #endif
300 
301 
302 /* Free memory returned from module_alloc */
303 void module_free(struct module *mod, void *module_region)
304 {
305 	kfree(mod->arch.section);
306 	mod->arch.section = NULL;
307 
308 	vfree(module_region);
309 }
310 
311 /* Additional bytes needed in front of individual sections */
312 unsigned int arch_mod_section_prepend(struct module *mod,
313 				      unsigned int section)
314 {
315 	/* size needed for all stubs of this section (including
316 	 * one additional for correct alignment of the stubs) */
317 	return (mod->arch.section[section].stub_entries + 1)
318 		* sizeof(struct stub_entry);
319 }
320 
321 #define CONST
322 int module_frob_arch_sections(CONST Elf_Ehdr *hdr,
323 			      CONST Elf_Shdr *sechdrs,
324 			      CONST char *secstrings,
325 			      struct module *me)
326 {
327 	unsigned long gots = 0, fdescs = 0, len;
328 	unsigned int i;
329 
330 	len = hdr->e_shnum * sizeof(me->arch.section[0]);
331 	me->arch.section = kzalloc(len, GFP_KERNEL);
332 	if (!me->arch.section)
333 		return -ENOMEM;
334 
335 	for (i = 1; i < hdr->e_shnum; i++) {
336 		const Elf_Rela *rels = (void *)sechdrs[i].sh_addr;
337 		unsigned long nrels = sechdrs[i].sh_size / sizeof(*rels);
338 		unsigned int count, s;
339 
340 		if (strncmp(secstrings + sechdrs[i].sh_name,
341 			    ".PARISC.unwind", 14) == 0)
342 			me->arch.unwind_section = i;
343 
344 		if (sechdrs[i].sh_type != SHT_RELA)
345 			continue;
346 
347 		/* some of these are not relevant for 32-bit/64-bit
348 		 * we leave them here to make the code common. the
349 		 * compiler will do its thing and optimize out the
350 		 * stuff we don't need
351 		 */
352 		gots += count_gots(rels, nrels);
353 		fdescs += count_fdescs(rels, nrels);
354 
355 		/* XXX: By sorting the relocs and finding duplicate entries
356 		 *  we could reduce the number of necessary stubs and save
357 		 *  some memory. */
358 		count = count_stubs(rels, nrels);
359 		if (!count)
360 			continue;
361 
362 		/* so we need relocation stubs. reserve necessary memory. */
363 		/* sh_info gives the section for which we need to add stubs. */
364 		s = sechdrs[i].sh_info;
365 
366 		/* each code section should only have one relocation section */
367 		WARN_ON(me->arch.section[s].stub_entries);
368 
369 		/* store number of stubs we need for this section */
370 		me->arch.section[s].stub_entries += count;
371 	}
372 
373 	/* align things a bit */
374 	me->core_size = ALIGN(me->core_size, 16);
375 	me->arch.got_offset = me->core_size;
376 	me->core_size += gots * sizeof(struct got_entry);
377 
378 	me->core_size = ALIGN(me->core_size, 16);
379 	me->arch.fdesc_offset = me->core_size;
380 	me->core_size += fdescs * sizeof(Elf_Fdesc);
381 
382 	me->arch.got_max = gots;
383 	me->arch.fdesc_max = fdescs;
384 
385 	return 0;
386 }
387 
388 #ifdef CONFIG_64BIT
389 static Elf64_Word get_got(struct module *me, unsigned long value, long addend)
390 {
391 	unsigned int i;
392 	struct got_entry *got;
393 
394 	value += addend;
395 
396 	BUG_ON(value == 0);
397 
398 	got = me->module_core + me->arch.got_offset;
399 	for (i = 0; got[i].addr; i++)
400 		if (got[i].addr == value)
401 			goto out;
402 
403 	BUG_ON(++me->arch.got_count > me->arch.got_max);
404 
405 	got[i].addr = value;
406  out:
407 	DEBUGP("GOT ENTRY %d[%x] val %lx\n", i, i*sizeof(struct got_entry),
408 	       value);
409 	return i * sizeof(struct got_entry);
410 }
411 #endif /* CONFIG_64BIT */
412 
413 #ifdef CONFIG_64BIT
414 static Elf_Addr get_fdesc(struct module *me, unsigned long value)
415 {
416 	Elf_Fdesc *fdesc = me->module_core + me->arch.fdesc_offset;
417 
418 	if (!value) {
419 		printk(KERN_ERR "%s: zero OPD requested!\n", me->name);
420 		return 0;
421 	}
422 
423 	/* Look for existing fdesc entry. */
424 	while (fdesc->addr) {
425 		if (fdesc->addr == value)
426 			return (Elf_Addr)fdesc;
427 		fdesc++;
428 	}
429 
430 	BUG_ON(++me->arch.fdesc_count > me->arch.fdesc_max);
431 
432 	/* Create new one */
433 	fdesc->addr = value;
434 	fdesc->gp = (Elf_Addr)me->module_core + me->arch.got_offset;
435 	return (Elf_Addr)fdesc;
436 }
437 #endif /* CONFIG_64BIT */
438 
439 enum elf_stub_type {
440 	ELF_STUB_GOT,
441 	ELF_STUB_MILLI,
442 	ELF_STUB_DIRECT,
443 };
444 
445 static Elf_Addr get_stub(struct module *me, unsigned long value, long addend,
446 	enum elf_stub_type stub_type, Elf_Addr loc0, unsigned int targetsec)
447 {
448 	struct stub_entry *stub;
449 	int __maybe_unused d;
450 
451 	/* initialize stub_offset to point in front of the section */
452 	if (!me->arch.section[targetsec].stub_offset) {
453 		loc0 -= (me->arch.section[targetsec].stub_entries + 1) *
454 				sizeof(struct stub_entry);
455 		/* get correct alignment for the stubs */
456 		loc0 = ALIGN(loc0, sizeof(struct stub_entry));
457 		me->arch.section[targetsec].stub_offset = loc0;
458 	}
459 
460 	/* get address of stub entry */
461 	stub = (void *) me->arch.section[targetsec].stub_offset;
462 	me->arch.section[targetsec].stub_offset += sizeof(struct stub_entry);
463 
464 	/* do not write outside available stub area */
465 	BUG_ON(0 == me->arch.section[targetsec].stub_entries--);
466 
467 
468 #ifndef CONFIG_64BIT
469 /* for 32-bit the stub looks like this:
470  * 	ldil L'XXX,%r1
471  * 	be,n R'XXX(%sr4,%r1)
472  */
473 	//value = *(unsigned long *)((value + addend) & ~3); /* why? */
474 
475 	stub->insns[0] = 0x20200000;	/* ldil L'XXX,%r1	*/
476 	stub->insns[1] = 0xe0202002;	/* be,n R'XXX(%sr4,%r1)	*/
477 
478 	stub->insns[0] |= reassemble_21(lrsel(value, addend));
479 	stub->insns[1] |= reassemble_17(rrsel(value, addend) / 4);
480 
481 #else
482 /* for 64-bit we have three kinds of stubs:
483  * for normal function calls:
484  * 	ldd 0(%dp),%dp
485  * 	ldd 10(%dp), %r1
486  * 	bve (%r1)
487  * 	ldd 18(%dp), %dp
488  *
489  * for millicode:
490  * 	ldil 0, %r1
491  * 	ldo 0(%r1), %r1
492  * 	ldd 10(%r1), %r1
493  * 	bve,n (%r1)
494  *
495  * for direct branches (jumps between different section of the
496  * same module):
497  *	ldil 0, %r1
498  *	ldo 0(%r1), %r1
499  *	bve,n (%r1)
500  */
501 	switch (stub_type) {
502 	case ELF_STUB_GOT:
503 		d = get_got(me, value, addend);
504 		if (d <= 15) {
505 			/* Format 5 */
506 			stub->insns[0] = 0x0f6010db; /* ldd 0(%dp),%dp	*/
507 			stub->insns[0] |= low_sign_unext(d, 5) << 16;
508 		} else {
509 			/* Format 3 */
510 			stub->insns[0] = 0x537b0000; /* ldd 0(%dp),%dp	*/
511 			stub->insns[0] |= reassemble_16a(d);
512 		}
513 		stub->insns[1] = 0x53610020;	/* ldd 10(%dp),%r1	*/
514 		stub->insns[2] = 0xe820d000;	/* bve (%r1)		*/
515 		stub->insns[3] = 0x537b0030;	/* ldd 18(%dp),%dp	*/
516 		break;
517 	case ELF_STUB_MILLI:
518 		stub->insns[0] = 0x20200000;	/* ldil 0,%r1		*/
519 		stub->insns[1] = 0x34210000;	/* ldo 0(%r1), %r1	*/
520 		stub->insns[2] = 0x50210020;	/* ldd 10(%r1),%r1	*/
521 		stub->insns[3] = 0xe820d002;	/* bve,n (%r1)		*/
522 
523 		stub->insns[0] |= reassemble_21(lrsel(value, addend));
524 		stub->insns[1] |= reassemble_14(rrsel(value, addend));
525 		break;
526 	case ELF_STUB_DIRECT:
527 		stub->insns[0] = 0x20200000;    /* ldil 0,%r1           */
528 		stub->insns[1] = 0x34210000;    /* ldo 0(%r1), %r1      */
529 		stub->insns[2] = 0xe820d002;    /* bve,n (%r1)          */
530 
531 		stub->insns[0] |= reassemble_21(lrsel(value, addend));
532 		stub->insns[1] |= reassemble_14(rrsel(value, addend));
533 		break;
534 	}
535 
536 #endif
537 
538 	return (Elf_Addr)stub;
539 }
540 
541 #ifndef CONFIG_64BIT
542 int apply_relocate_add(Elf_Shdr *sechdrs,
543 		       const char *strtab,
544 		       unsigned int symindex,
545 		       unsigned int relsec,
546 		       struct module *me)
547 {
548 	int i;
549 	Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
550 	Elf32_Sym *sym;
551 	Elf32_Word *loc;
552 	Elf32_Addr val;
553 	Elf32_Sword addend;
554 	Elf32_Addr dot;
555 	Elf_Addr loc0;
556 	unsigned int targetsec = sechdrs[relsec].sh_info;
557 	//unsigned long dp = (unsigned long)$global$;
558 	register unsigned long dp asm ("r27");
559 
560 	DEBUGP("Applying relocate section %u to %u\n", relsec,
561 	       targetsec);
562 	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
563 		/* This is where to make the change */
564 		loc = (void *)sechdrs[targetsec].sh_addr
565 		      + rel[i].r_offset;
566 		/* This is the start of the target section */
567 		loc0 = sechdrs[targetsec].sh_addr;
568 		/* This is the symbol it is referring to */
569 		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
570 			+ ELF32_R_SYM(rel[i].r_info);
571 		if (!sym->st_value) {
572 			printk(KERN_WARNING "%s: Unknown symbol %s\n",
573 			       me->name, strtab + sym->st_name);
574 			return -ENOENT;
575 		}
576 		//dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
577 		dot =  (Elf32_Addr)loc & ~0x03;
578 
579 		val = sym->st_value;
580 		addend = rel[i].r_addend;
581 
582 #if 0
583 #define r(t) ELF32_R_TYPE(rel[i].r_info)==t ? #t :
584 		DEBUGP("Symbol %s loc 0x%x val 0x%x addend 0x%x: %s\n",
585 			strtab + sym->st_name,
586 			(uint32_t)loc, val, addend,
587 			r(R_PARISC_PLABEL32)
588 			r(R_PARISC_DIR32)
589 			r(R_PARISC_DIR21L)
590 			r(R_PARISC_DIR14R)
591 			r(R_PARISC_SEGREL32)
592 			r(R_PARISC_DPREL21L)
593 			r(R_PARISC_DPREL14R)
594 			r(R_PARISC_PCREL17F)
595 			r(R_PARISC_PCREL22F)
596 			"UNKNOWN");
597 #undef r
598 #endif
599 
600 		switch (ELF32_R_TYPE(rel[i].r_info)) {
601 		case R_PARISC_PLABEL32:
602 			/* 32-bit function address */
603 			/* no function descriptors... */
604 			*loc = fsel(val, addend);
605 			break;
606 		case R_PARISC_DIR32:
607 			/* direct 32-bit ref */
608 			*loc = fsel(val, addend);
609 			break;
610 		case R_PARISC_DIR21L:
611 			/* left 21 bits of effective address */
612 			val = lrsel(val, addend);
613 			*loc = mask(*loc, 21) | reassemble_21(val);
614 			break;
615 		case R_PARISC_DIR14R:
616 			/* right 14 bits of effective address */
617 			val = rrsel(val, addend);
618 			*loc = mask(*loc, 14) | reassemble_14(val);
619 			break;
620 		case R_PARISC_SEGREL32:
621 			/* 32-bit segment relative address */
622 			/* See note about special handling of SEGREL32 at
623 			 * the beginning of this file.
624 			 */
625 			*loc = fsel(val, addend);
626 			break;
627 		case R_PARISC_DPREL21L:
628 			/* left 21 bit of relative address */
629 			val = lrsel(val - dp, addend);
630 			*loc = mask(*loc, 21) | reassemble_21(val);
631 			break;
632 		case R_PARISC_DPREL14R:
633 			/* right 14 bit of relative address */
634 			val = rrsel(val - dp, addend);
635 			*loc = mask(*loc, 14) | reassemble_14(val);
636 			break;
637 		case R_PARISC_PCREL17F:
638 			/* 17-bit PC relative address */
639 			/* calculate direct call offset */
640 			val += addend;
641 			val = (val - dot - 8)/4;
642 			if (!RELOC_REACHABLE(val, 17)) {
643 				/* direct distance too far, create
644 				 * stub entry instead */
645 				val = get_stub(me, sym->st_value, addend,
646 					ELF_STUB_DIRECT, loc0, targetsec);
647 				val = (val - dot - 8)/4;
648 				CHECK_RELOC(val, 17);
649 			}
650 			*loc = (*loc & ~0x1f1ffd) | reassemble_17(val);
651 			break;
652 		case R_PARISC_PCREL22F:
653 			/* 22-bit PC relative address; only defined for pa20 */
654 			/* calculate direct call offset */
655 			val += addend;
656 			val = (val - dot - 8)/4;
657 			if (!RELOC_REACHABLE(val, 22)) {
658 				/* direct distance too far, create
659 				 * stub entry instead */
660 				val = get_stub(me, sym->st_value, addend,
661 					ELF_STUB_DIRECT, loc0, targetsec);
662 				val = (val - dot - 8)/4;
663 				CHECK_RELOC(val, 22);
664 			}
665 			*loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
666 			break;
667 
668 		default:
669 			printk(KERN_ERR "module %s: Unknown relocation: %u\n",
670 			       me->name, ELF32_R_TYPE(rel[i].r_info));
671 			return -ENOEXEC;
672 		}
673 	}
674 
675 	return 0;
676 }
677 
678 #else
679 int apply_relocate_add(Elf_Shdr *sechdrs,
680 		       const char *strtab,
681 		       unsigned int symindex,
682 		       unsigned int relsec,
683 		       struct module *me)
684 {
685 	int i;
686 	Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr;
687 	Elf64_Sym *sym;
688 	Elf64_Word *loc;
689 	Elf64_Xword *loc64;
690 	Elf64_Addr val;
691 	Elf64_Sxword addend;
692 	Elf64_Addr dot;
693 	Elf_Addr loc0;
694 	unsigned int targetsec = sechdrs[relsec].sh_info;
695 
696 	DEBUGP("Applying relocate section %u to %u\n", relsec,
697 	       targetsec);
698 	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
699 		/* This is where to make the change */
700 		loc = (void *)sechdrs[targetsec].sh_addr
701 		      + rel[i].r_offset;
702 		/* This is the start of the target section */
703 		loc0 = sechdrs[targetsec].sh_addr;
704 		/* This is the symbol it is referring to */
705 		sym = (Elf64_Sym *)sechdrs[symindex].sh_addr
706 			+ ELF64_R_SYM(rel[i].r_info);
707 		if (!sym->st_value) {
708 			printk(KERN_WARNING "%s: Unknown symbol %s\n",
709 			       me->name, strtab + sym->st_name);
710 			return -ENOENT;
711 		}
712 		//dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
713 		dot = (Elf64_Addr)loc & ~0x03;
714 		loc64 = (Elf64_Xword *)loc;
715 
716 		val = sym->st_value;
717 		addend = rel[i].r_addend;
718 
719 #if 0
720 #define r(t) ELF64_R_TYPE(rel[i].r_info)==t ? #t :
721 		printk("Symbol %s loc %p val 0x%Lx addend 0x%Lx: %s\n",
722 			strtab + sym->st_name,
723 			loc, val, addend,
724 			r(R_PARISC_LTOFF14R)
725 			r(R_PARISC_LTOFF21L)
726 			r(R_PARISC_PCREL22F)
727 			r(R_PARISC_DIR64)
728 			r(R_PARISC_SEGREL32)
729 			r(R_PARISC_FPTR64)
730 			"UNKNOWN");
731 #undef r
732 #endif
733 
734 		switch (ELF64_R_TYPE(rel[i].r_info)) {
735 		case R_PARISC_LTOFF21L:
736 			/* LT-relative; left 21 bits */
737 			val = get_got(me, val, addend);
738 			DEBUGP("LTOFF21L Symbol %s loc %p val %lx\n",
739 			       strtab + sym->st_name,
740 			       loc, val);
741 			val = lrsel(val, 0);
742 			*loc = mask(*loc, 21) | reassemble_21(val);
743 			break;
744 		case R_PARISC_LTOFF14R:
745 			/* L(ltoff(val+addend)) */
746 			/* LT-relative; right 14 bits */
747 			val = get_got(me, val, addend);
748 			val = rrsel(val, 0);
749 			DEBUGP("LTOFF14R Symbol %s loc %p val %lx\n",
750 			       strtab + sym->st_name,
751 			       loc, val);
752 			*loc = mask(*loc, 14) | reassemble_14(val);
753 			break;
754 		case R_PARISC_PCREL22F:
755 			/* PC-relative; 22 bits */
756 			DEBUGP("PCREL22F Symbol %s loc %p val %lx\n",
757 			       strtab + sym->st_name,
758 			       loc, val);
759 			val += addend;
760 			/* can we reach it locally? */
761 			if (in_local(me, (void *)val)) {
762 				/* this is the case where the symbol is local
763 				 * to the module, but in a different section,
764 				 * so stub the jump in case it's more than 22
765 				 * bits away */
766 				val = (val - dot - 8)/4;
767 				if (!RELOC_REACHABLE(val, 22)) {
768 					/* direct distance too far, create
769 					 * stub entry instead */
770 					val = get_stub(me, sym->st_value,
771 						addend, ELF_STUB_DIRECT,
772 						loc0, targetsec);
773 				} else {
774 					/* Ok, we can reach it directly. */
775 					val = sym->st_value;
776 					val += addend;
777 				}
778 			} else {
779 				val = sym->st_value;
780 				if (strncmp(strtab + sym->st_name, "$$", 2)
781 				    == 0)
782 					val = get_stub(me, val, addend, ELF_STUB_MILLI,
783 						       loc0, targetsec);
784 				else
785 					val = get_stub(me, val, addend, ELF_STUB_GOT,
786 						       loc0, targetsec);
787 			}
788 			DEBUGP("STUB FOR %s loc %lx, val %lx+%lx at %lx\n",
789 			       strtab + sym->st_name, loc, sym->st_value,
790 			       addend, val);
791 			val = (val - dot - 8)/4;
792 			CHECK_RELOC(val, 22);
793 			*loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
794 			break;
795 		case R_PARISC_DIR64:
796 			/* 64-bit effective address */
797 			*loc64 = val + addend;
798 			break;
799 		case R_PARISC_SEGREL32:
800 			/* 32-bit segment relative address */
801 			/* See note about special handling of SEGREL32 at
802 			 * the beginning of this file.
803 			 */
804 			*loc = fsel(val, addend);
805 			break;
806 		case R_PARISC_FPTR64:
807 			/* 64-bit function address */
808 			if(in_local(me, (void *)(val + addend))) {
809 				*loc64 = get_fdesc(me, val+addend);
810 				DEBUGP("FDESC for %s at %p points to %lx\n",
811 				       strtab + sym->st_name, *loc64,
812 				       ((Elf_Fdesc *)*loc64)->addr);
813 			} else {
814 				/* if the symbol is not local to this
815 				 * module then val+addend is a pointer
816 				 * to the function descriptor */
817 				DEBUGP("Non local FPTR64 Symbol %s loc %p val %lx\n",
818 				       strtab + sym->st_name,
819 				       loc, val);
820 				*loc64 = val + addend;
821 			}
822 			break;
823 
824 		default:
825 			printk(KERN_ERR "module %s: Unknown relocation: %Lu\n",
826 			       me->name, ELF64_R_TYPE(rel[i].r_info));
827 			return -ENOEXEC;
828 		}
829 	}
830 	return 0;
831 }
832 #endif
833 
834 static void
835 register_unwind_table(struct module *me,
836 		      const Elf_Shdr *sechdrs)
837 {
838 	unsigned char *table, *end;
839 	unsigned long gp;
840 
841 	if (!me->arch.unwind_section)
842 		return;
843 
844 	table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr;
845 	end = table + sechdrs[me->arch.unwind_section].sh_size;
846 	gp = (Elf_Addr)me->module_core + me->arch.got_offset;
847 
848 	DEBUGP("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n",
849 	       me->arch.unwind_section, table, end, gp);
850 	me->arch.unwind = unwind_table_add(me->name, 0, gp, table, end);
851 }
852 
853 static void
854 deregister_unwind_table(struct module *me)
855 {
856 	if (me->arch.unwind)
857 		unwind_table_remove(me->arch.unwind);
858 }
859 
860 int module_finalize(const Elf_Ehdr *hdr,
861 		    const Elf_Shdr *sechdrs,
862 		    struct module *me)
863 {
864 	int i;
865 	unsigned long nsyms;
866 	const char *strtab = NULL;
867 	Elf_Sym *newptr, *oldptr;
868 	Elf_Shdr *symhdr = NULL;
869 #ifdef DEBUG
870 	Elf_Fdesc *entry;
871 	u32 *addr;
872 
873 	entry = (Elf_Fdesc *)me->init;
874 	printk("FINALIZE, ->init FPTR is %p, GP %lx ADDR %lx\n", entry,
875 	       entry->gp, entry->addr);
876 	addr = (u32 *)entry->addr;
877 	printk("INSNS: %x %x %x %x\n",
878 	       addr[0], addr[1], addr[2], addr[3]);
879 	printk("got entries used %ld, gots max %ld\n"
880 	       "fdescs used %ld, fdescs max %ld\n",
881 	       me->arch.got_count, me->arch.got_max,
882 	       me->arch.fdesc_count, me->arch.fdesc_max);
883 #endif
884 
885 	register_unwind_table(me, sechdrs);
886 
887 	/* haven't filled in me->symtab yet, so have to find it
888 	 * ourselves */
889 	for (i = 1; i < hdr->e_shnum; i++) {
890 		if(sechdrs[i].sh_type == SHT_SYMTAB
891 		   && (sechdrs[i].sh_flags & SHF_ALLOC)) {
892 			int strindex = sechdrs[i].sh_link;
893 			/* FIXME: AWFUL HACK
894 			 * The cast is to drop the const from
895 			 * the sechdrs pointer */
896 			symhdr = (Elf_Shdr *)&sechdrs[i];
897 			strtab = (char *)sechdrs[strindex].sh_addr;
898 			break;
899 		}
900 	}
901 
902 	DEBUGP("module %s: strtab %p, symhdr %p\n",
903 	       me->name, strtab, symhdr);
904 
905 	if(me->arch.got_count > MAX_GOTS) {
906 		printk(KERN_ERR "%s: Global Offset Table overflow (used %ld, allowed %d)\n",
907 				me->name, me->arch.got_count, MAX_GOTS);
908 		return -EINVAL;
909 	}
910 
911 	kfree(me->arch.section);
912 	me->arch.section = NULL;
913 
914 	/* no symbol table */
915 	if(symhdr == NULL)
916 		return 0;
917 
918 	oldptr = (void *)symhdr->sh_addr;
919 	newptr = oldptr + 1;	/* we start counting at 1 */
920 	nsyms = symhdr->sh_size / sizeof(Elf_Sym);
921 	DEBUGP("OLD num_symtab %lu\n", nsyms);
922 
923 	for (i = 1; i < nsyms; i++) {
924 		oldptr++;	/* note, count starts at 1 so preincrement */
925 		if(strncmp(strtab + oldptr->st_name,
926 			      ".L", 2) == 0)
927 			continue;
928 
929 		if(newptr != oldptr)
930 			*newptr++ = *oldptr;
931 		else
932 			newptr++;
933 
934 	}
935 	nsyms = newptr - (Elf_Sym *)symhdr->sh_addr;
936 	DEBUGP("NEW num_symtab %lu\n", nsyms);
937 	symhdr->sh_size = nsyms * sizeof(Elf_Sym);
938 	return 0;
939 }
940 
941 void module_arch_cleanup(struct module *mod)
942 {
943 	deregister_unwind_table(mod);
944 }
945