1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 2004, 2005 MIPS Technologies, Inc. All rights reserved.
7 * Copyright (C) 2013 Imagination Technologies Ltd.
8 *
9 * VPE spport module for loading a MIPS SP program into VPE1. The SP
10 * environment is rather simple since there are no TLBs. It needs
11 * to be relocatable (or partiall linked). Initialize your stack in
12 * the startup-code. The loader looks for the symbol __start and sets
13 * up the execution to resume from there. To load and run, simply do
14 * a cat SP 'binary' to the /dev/vpe1 device.
15 */
16 #include <linux/kernel.h>
17 #include <linux/device.h>
18 #include <linux/fs.h>
19 #include <linux/init.h>
20 #include <linux/slab.h>
21 #include <linux/list.h>
22 #include <linux/vmalloc.h>
23 #include <linux/elf.h>
24 #include <linux/seq_file.h>
25 #include <linux/syscalls.h>
26 #include <linux/moduleloader.h>
27 #include <linux/interrupt.h>
28 #include <linux/poll.h>
29 #include <linux/bootmem.h>
30 #include <asm/mipsregs.h>
31 #include <asm/mipsmtregs.h>
32 #include <asm/cacheflush.h>
33 #include <linux/atomic.h>
34 #include <asm/mips_mt.h>
35 #include <asm/processor.h>
36 #include <asm/vpe.h>
37
38 #ifndef ARCH_SHF_SMALL
39 #define ARCH_SHF_SMALL 0
40 #endif
41
42 /* If this is set, the section belongs in the init part of the module */
43 #define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
44
45 struct vpe_control vpecontrol = {
46 .vpe_list_lock = __SPIN_LOCK_UNLOCKED(vpe_list_lock),
47 .vpe_list = LIST_HEAD_INIT(vpecontrol.vpe_list),
48 .tc_list_lock = __SPIN_LOCK_UNLOCKED(tc_list_lock),
49 .tc_list = LIST_HEAD_INIT(vpecontrol.tc_list)
50 };
51
52 /* get the vpe associated with this minor */
get_vpe(int minor)53 struct vpe *get_vpe(int minor)
54 {
55 struct vpe *res, *v;
56
57 if (!cpu_has_mipsmt)
58 return NULL;
59
60 res = NULL;
61 spin_lock(&vpecontrol.vpe_list_lock);
62 list_for_each_entry(v, &vpecontrol.vpe_list, list) {
63 if (v->minor == VPE_MODULE_MINOR) {
64 res = v;
65 break;
66 }
67 }
68 spin_unlock(&vpecontrol.vpe_list_lock);
69
70 return res;
71 }
72
73 /* get the vpe associated with this minor */
get_tc(int index)74 struct tc *get_tc(int index)
75 {
76 struct tc *res, *t;
77
78 res = NULL;
79 spin_lock(&vpecontrol.tc_list_lock);
80 list_for_each_entry(t, &vpecontrol.tc_list, list) {
81 if (t->index == index) {
82 res = t;
83 break;
84 }
85 }
86 spin_unlock(&vpecontrol.tc_list_lock);
87
88 return res;
89 }
90
91 /* allocate a vpe and associate it with this minor (or index) */
alloc_vpe(int minor)92 struct vpe *alloc_vpe(int minor)
93 {
94 struct vpe *v;
95
96 v = kzalloc(sizeof(struct vpe), GFP_KERNEL);
97 if (v == NULL)
98 goto out;
99
100 INIT_LIST_HEAD(&v->tc);
101 spin_lock(&vpecontrol.vpe_list_lock);
102 list_add_tail(&v->list, &vpecontrol.vpe_list);
103 spin_unlock(&vpecontrol.vpe_list_lock);
104
105 INIT_LIST_HEAD(&v->notify);
106 v->minor = VPE_MODULE_MINOR;
107
108 out:
109 return v;
110 }
111
112 /* allocate a tc. At startup only tc0 is running, all other can be halted. */
alloc_tc(int index)113 struct tc *alloc_tc(int index)
114 {
115 struct tc *tc;
116
117 tc = kzalloc(sizeof(struct tc), GFP_KERNEL);
118 if (tc == NULL)
119 goto out;
120
121 INIT_LIST_HEAD(&tc->tc);
122 tc->index = index;
123
124 spin_lock(&vpecontrol.tc_list_lock);
125 list_add_tail(&tc->list, &vpecontrol.tc_list);
126 spin_unlock(&vpecontrol.tc_list_lock);
127
128 out:
129 return tc;
130 }
131
132 /* clean up and free everything */
release_vpe(struct vpe * v)133 void release_vpe(struct vpe *v)
134 {
135 list_del(&v->list);
136 if (v->load_addr)
137 release_progmem(v);
138 kfree(v);
139 }
140
141 /* Find some VPE program space */
alloc_progmem(unsigned long len)142 void *alloc_progmem(unsigned long len)
143 {
144 void *addr;
145
146 #ifdef CONFIG_MIPS_VPE_LOADER_TOM
147 /*
148 * This means you must tell Linux to use less memory than you
149 * physically have, for example by passing a mem= boot argument.
150 */
151 addr = pfn_to_kaddr(max_low_pfn);
152 memset(addr, 0, len);
153 #else
154 /* simple grab some mem for now */
155 addr = kzalloc(len, GFP_KERNEL);
156 #endif
157
158 return addr;
159 }
160
release_progmem(void * ptr)161 void release_progmem(void *ptr)
162 {
163 #ifndef CONFIG_MIPS_VPE_LOADER_TOM
164 kfree(ptr);
165 #endif
166 }
167
168 /* Update size with this section: return offset. */
get_offset(unsigned long * size,Elf_Shdr * sechdr)169 static long get_offset(unsigned long *size, Elf_Shdr *sechdr)
170 {
171 long ret;
172
173 ret = ALIGN(*size, sechdr->sh_addralign ? : 1);
174 *size = ret + sechdr->sh_size;
175 return ret;
176 }
177
178 /* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
179 might -- code, read-only data, read-write data, small data. Tally
180 sizes, and place the offsets into sh_entsize fields: high bit means it
181 belongs in init. */
layout_sections(struct module * mod,const Elf_Ehdr * hdr,Elf_Shdr * sechdrs,const char * secstrings)182 static void layout_sections(struct module *mod, const Elf_Ehdr *hdr,
183 Elf_Shdr *sechdrs, const char *secstrings)
184 {
185 static unsigned long const masks[][2] = {
186 /* NOTE: all executable code must be the first section
187 * in this array; otherwise modify the text_size
188 * finder in the two loops below */
189 {SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL},
190 {SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL},
191 {SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL},
192 {ARCH_SHF_SMALL | SHF_ALLOC, 0}
193 };
194 unsigned int m, i;
195
196 for (i = 0; i < hdr->e_shnum; i++)
197 sechdrs[i].sh_entsize = ~0UL;
198
199 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
200 for (i = 0; i < hdr->e_shnum; ++i) {
201 Elf_Shdr *s = &sechdrs[i];
202
203 if ((s->sh_flags & masks[m][0]) != masks[m][0]
204 || (s->sh_flags & masks[m][1])
205 || s->sh_entsize != ~0UL)
206 continue;
207 s->sh_entsize =
208 get_offset((unsigned long *)&mod->core_size, s);
209 }
210
211 if (m == 0)
212 mod->core_text_size = mod->core_size;
213
214 }
215 }
216
217 /* from module-elf32.c, but subverted a little */
218
219 struct mips_hi16 {
220 struct mips_hi16 *next;
221 Elf32_Addr *addr;
222 Elf32_Addr value;
223 };
224
225 static struct mips_hi16 *mips_hi16_list;
226 static unsigned int gp_offs, gp_addr;
227
apply_r_mips_none(struct module * me,uint32_t * location,Elf32_Addr v)228 static int apply_r_mips_none(struct module *me, uint32_t *location,
229 Elf32_Addr v)
230 {
231 return 0;
232 }
233
apply_r_mips_gprel16(struct module * me,uint32_t * location,Elf32_Addr v)234 static int apply_r_mips_gprel16(struct module *me, uint32_t *location,
235 Elf32_Addr v)
236 {
237 int rel;
238
239 if (!(*location & 0xffff)) {
240 rel = (int)v - gp_addr;
241 } else {
242 /* .sbss + gp(relative) + offset */
243 /* kludge! */
244 rel = (int)(short)((int)v + gp_offs +
245 (int)(short)(*location & 0xffff) - gp_addr);
246 }
247
248 if ((rel > 32768) || (rel < -32768)) {
249 pr_debug("VPE loader: apply_r_mips_gprel16: relative address 0x%x out of range of gp register\n",
250 rel);
251 return -ENOEXEC;
252 }
253
254 *location = (*location & 0xffff0000) | (rel & 0xffff);
255
256 return 0;
257 }
258
apply_r_mips_pc16(struct module * me,uint32_t * location,Elf32_Addr v)259 static int apply_r_mips_pc16(struct module *me, uint32_t *location,
260 Elf32_Addr v)
261 {
262 int rel;
263 rel = (((unsigned int)v - (unsigned int)location));
264 rel >>= 2; /* because the offset is in _instructions_ not bytes. */
265 rel -= 1; /* and one instruction less due to the branch delay slot. */
266
267 if ((rel > 32768) || (rel < -32768)) {
268 pr_debug("VPE loader: apply_r_mips_pc16: relative address out of range 0x%x\n",
269 rel);
270 return -ENOEXEC;
271 }
272
273 *location = (*location & 0xffff0000) | (rel & 0xffff);
274
275 return 0;
276 }
277
apply_r_mips_32(struct module * me,uint32_t * location,Elf32_Addr v)278 static int apply_r_mips_32(struct module *me, uint32_t *location,
279 Elf32_Addr v)
280 {
281 *location += v;
282
283 return 0;
284 }
285
apply_r_mips_26(struct module * me,uint32_t * location,Elf32_Addr v)286 static int apply_r_mips_26(struct module *me, uint32_t *location,
287 Elf32_Addr v)
288 {
289 if (v % 4) {
290 pr_debug("VPE loader: apply_r_mips_26: unaligned relocation\n");
291 return -ENOEXEC;
292 }
293
294 /*
295 * Not desperately convinced this is a good check of an overflow condition
296 * anyway. But it gets in the way of handling undefined weak symbols which
297 * we want to set to zero.
298 * if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
299 * printk(KERN_ERR
300 * "module %s: relocation overflow\n",
301 * me->name);
302 * return -ENOEXEC;
303 * }
304 */
305
306 *location = (*location & ~0x03ffffff) |
307 ((*location + (v >> 2)) & 0x03ffffff);
308 return 0;
309 }
310
apply_r_mips_hi16(struct module * me,uint32_t * location,Elf32_Addr v)311 static int apply_r_mips_hi16(struct module *me, uint32_t *location,
312 Elf32_Addr v)
313 {
314 struct mips_hi16 *n;
315
316 /*
317 * We cannot relocate this one now because we don't know the value of
318 * the carry we need to add. Save the information, and let LO16 do the
319 * actual relocation.
320 */
321 n = kmalloc(sizeof(*n), GFP_KERNEL);
322 if (!n)
323 return -ENOMEM;
324
325 n->addr = location;
326 n->value = v;
327 n->next = mips_hi16_list;
328 mips_hi16_list = n;
329
330 return 0;
331 }
332
apply_r_mips_lo16(struct module * me,uint32_t * location,Elf32_Addr v)333 static int apply_r_mips_lo16(struct module *me, uint32_t *location,
334 Elf32_Addr v)
335 {
336 unsigned long insnlo = *location;
337 Elf32_Addr val, vallo;
338 struct mips_hi16 *l, *next;
339
340 /* Sign extend the addend we extract from the lo insn. */
341 vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
342
343 if (mips_hi16_list != NULL) {
344
345 l = mips_hi16_list;
346 while (l != NULL) {
347 unsigned long insn;
348
349 /*
350 * The value for the HI16 had best be the same.
351 */
352 if (v != l->value) {
353 pr_debug("VPE loader: apply_r_mips_lo16/hi16: inconsistent value information\n");
354 goto out_free;
355 }
356
357 /*
358 * Do the HI16 relocation. Note that we actually don't
359 * need to know anything about the LO16 itself, except
360 * where to find the low 16 bits of the addend needed
361 * by the LO16.
362 */
363 insn = *l->addr;
364 val = ((insn & 0xffff) << 16) + vallo;
365 val += v;
366
367 /*
368 * Account for the sign extension that will happen in
369 * the low bits.
370 */
371 val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;
372
373 insn = (insn & ~0xffff) | val;
374 *l->addr = insn;
375
376 next = l->next;
377 kfree(l);
378 l = next;
379 }
380
381 mips_hi16_list = NULL;
382 }
383
384 /*
385 * Ok, we're done with the HI16 relocs. Now deal with the LO16.
386 */
387 val = v + vallo;
388 insnlo = (insnlo & ~0xffff) | (val & 0xffff);
389 *location = insnlo;
390
391 return 0;
392
393 out_free:
394 while (l != NULL) {
395 next = l->next;
396 kfree(l);
397 l = next;
398 }
399 mips_hi16_list = NULL;
400
401 return -ENOEXEC;
402 }
403
404 static int (*reloc_handlers[]) (struct module *me, uint32_t *location,
405 Elf32_Addr v) = {
406 [R_MIPS_NONE] = apply_r_mips_none,
407 [R_MIPS_32] = apply_r_mips_32,
408 [R_MIPS_26] = apply_r_mips_26,
409 [R_MIPS_HI16] = apply_r_mips_hi16,
410 [R_MIPS_LO16] = apply_r_mips_lo16,
411 [R_MIPS_GPREL16] = apply_r_mips_gprel16,
412 [R_MIPS_PC16] = apply_r_mips_pc16
413 };
414
415 static char *rstrs[] = {
416 [R_MIPS_NONE] = "MIPS_NONE",
417 [R_MIPS_32] = "MIPS_32",
418 [R_MIPS_26] = "MIPS_26",
419 [R_MIPS_HI16] = "MIPS_HI16",
420 [R_MIPS_LO16] = "MIPS_LO16",
421 [R_MIPS_GPREL16] = "MIPS_GPREL16",
422 [R_MIPS_PC16] = "MIPS_PC16"
423 };
424
apply_relocations(Elf32_Shdr * sechdrs,const char * strtab,unsigned int symindex,unsigned int relsec,struct module * me)425 static int apply_relocations(Elf32_Shdr *sechdrs,
426 const char *strtab,
427 unsigned int symindex,
428 unsigned int relsec,
429 struct module *me)
430 {
431 Elf32_Rel *rel = (void *) sechdrs[relsec].sh_addr;
432 Elf32_Sym *sym;
433 uint32_t *location;
434 unsigned int i;
435 Elf32_Addr v;
436 int res;
437
438 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
439 Elf32_Word r_info = rel[i].r_info;
440
441 /* This is where to make the change */
442 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
443 + rel[i].r_offset;
444 /* This is the symbol it is referring to */
445 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
446 + ELF32_R_SYM(r_info);
447
448 if (!sym->st_value) {
449 pr_debug("%s: undefined weak symbol %s\n",
450 me->name, strtab + sym->st_name);
451 /* just print the warning, dont barf */
452 }
453
454 v = sym->st_value;
455
456 res = reloc_handlers[ELF32_R_TYPE(r_info)](me, location, v);
457 if (res) {
458 char *r = rstrs[ELF32_R_TYPE(r_info)];
459 pr_warn("VPE loader: .text+0x%x relocation type %s for symbol \"%s\" failed\n",
460 rel[i].r_offset, r ? r : "UNKNOWN",
461 strtab + sym->st_name);
462 return res;
463 }
464 }
465
466 return 0;
467 }
468
save_gp_address(unsigned int secbase,unsigned int rel)469 static inline void save_gp_address(unsigned int secbase, unsigned int rel)
470 {
471 gp_addr = secbase + rel;
472 gp_offs = gp_addr - (secbase & 0xffff0000);
473 }
474 /* end module-elf32.c */
475
476 /* Change all symbols so that sh_value encodes the pointer directly. */
simplify_symbols(Elf_Shdr * sechdrs,unsigned int symindex,const char * strtab,const char * secstrings,unsigned int nsecs,struct module * mod)477 static void simplify_symbols(Elf_Shdr *sechdrs,
478 unsigned int symindex,
479 const char *strtab,
480 const char *secstrings,
481 unsigned int nsecs, struct module *mod)
482 {
483 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
484 unsigned long secbase, bssbase = 0;
485 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
486 int size;
487
488 /* find the .bss section for COMMON symbols */
489 for (i = 0; i < nsecs; i++) {
490 if (strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) == 0) {
491 bssbase = sechdrs[i].sh_addr;
492 break;
493 }
494 }
495
496 for (i = 1; i < n; i++) {
497 switch (sym[i].st_shndx) {
498 case SHN_COMMON:
499 /* Allocate space for the symbol in the .bss section.
500 st_value is currently size.
501 We want it to have the address of the symbol. */
502
503 size = sym[i].st_value;
504 sym[i].st_value = bssbase;
505
506 bssbase += size;
507 break;
508
509 case SHN_ABS:
510 /* Don't need to do anything */
511 break;
512
513 case SHN_UNDEF:
514 /* ret = -ENOENT; */
515 break;
516
517 case SHN_MIPS_SCOMMON:
518 pr_debug("simplify_symbols: ignoring SHN_MIPS_SCOMMON symbol <%s> st_shndx %d\n",
519 strtab + sym[i].st_name, sym[i].st_shndx);
520 /* .sbss section */
521 break;
522
523 default:
524 secbase = sechdrs[sym[i].st_shndx].sh_addr;
525
526 if (strncmp(strtab + sym[i].st_name, "_gp", 3) == 0)
527 save_gp_address(secbase, sym[i].st_value);
528
529 sym[i].st_value += secbase;
530 break;
531 }
532 }
533 }
534
535 #ifdef DEBUG_ELFLOADER
dump_elfsymbols(Elf_Shdr * sechdrs,unsigned int symindex,const char * strtab,struct module * mod)536 static void dump_elfsymbols(Elf_Shdr *sechdrs, unsigned int symindex,
537 const char *strtab, struct module *mod)
538 {
539 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
540 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
541
542 pr_debug("dump_elfsymbols: n %d\n", n);
543 for (i = 1; i < n; i++) {
544 pr_debug(" i %d name <%s> 0x%x\n", i, strtab + sym[i].st_name,
545 sym[i].st_value);
546 }
547 }
548 #endif
549
find_vpe_symbols(struct vpe * v,Elf_Shdr * sechdrs,unsigned int symindex,const char * strtab,struct module * mod)550 static int find_vpe_symbols(struct vpe *v, Elf_Shdr *sechdrs,
551 unsigned int symindex, const char *strtab,
552 struct module *mod)
553 {
554 Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
555 unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
556
557 for (i = 1; i < n; i++) {
558 if (strcmp(strtab + sym[i].st_name, "__start") == 0)
559 v->__start = sym[i].st_value;
560
561 if (strcmp(strtab + sym[i].st_name, "vpe_shared") == 0)
562 v->shared_ptr = (void *)sym[i].st_value;
563 }
564
565 if ((v->__start == 0) || (v->shared_ptr == NULL))
566 return -1;
567
568 return 0;
569 }
570
571 /*
572 * Allocates a VPE with some program code space(the load address), copies the
573 * contents of the program (p)buffer performing relocatations/etc, free's it
574 * when finished.
575 */
vpe_elfload(struct vpe * v)576 static int vpe_elfload(struct vpe *v)
577 {
578 Elf_Ehdr *hdr;
579 Elf_Shdr *sechdrs;
580 long err = 0;
581 char *secstrings, *strtab = NULL;
582 unsigned int len, i, symindex = 0, strindex = 0, relocate = 0;
583 struct module mod; /* so we can re-use the relocations code */
584
585 memset(&mod, 0, sizeof(struct module));
586 strcpy(mod.name, "VPE loader");
587
588 hdr = (Elf_Ehdr *) v->pbuffer;
589 len = v->plen;
590
591 /* Sanity checks against insmoding binaries or wrong arch,
592 weird elf version */
593 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
594 || (hdr->e_type != ET_REL && hdr->e_type != ET_EXEC)
595 || !elf_check_arch(hdr)
596 || hdr->e_shentsize != sizeof(*sechdrs)) {
597 pr_warn("VPE loader: program wrong arch or weird elf version\n");
598
599 return -ENOEXEC;
600 }
601
602 if (hdr->e_type == ET_REL)
603 relocate = 1;
604
605 if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
606 pr_err("VPE loader: program length %u truncated\n", len);
607
608 return -ENOEXEC;
609 }
610
611 /* Convenience variables */
612 sechdrs = (void *)hdr + hdr->e_shoff;
613 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
614 sechdrs[0].sh_addr = 0;
615
616 /* And these should exist, but gcc whinges if we don't init them */
617 symindex = strindex = 0;
618
619 if (relocate) {
620 for (i = 1; i < hdr->e_shnum; i++) {
621 if ((sechdrs[i].sh_type != SHT_NOBITS) &&
622 (len < sechdrs[i].sh_offset + sechdrs[i].sh_size)) {
623 pr_err("VPE program length %u truncated\n",
624 len);
625 return -ENOEXEC;
626 }
627
628 /* Mark all sections sh_addr with their address in the
629 temporary image. */
630 sechdrs[i].sh_addr = (size_t) hdr +
631 sechdrs[i].sh_offset;
632
633 /* Internal symbols and strings. */
634 if (sechdrs[i].sh_type == SHT_SYMTAB) {
635 symindex = i;
636 strindex = sechdrs[i].sh_link;
637 strtab = (char *)hdr +
638 sechdrs[strindex].sh_offset;
639 }
640 }
641 layout_sections(&mod, hdr, sechdrs, secstrings);
642 }
643
644 v->load_addr = alloc_progmem(mod.core_size);
645 if (!v->load_addr)
646 return -ENOMEM;
647
648 pr_info("VPE loader: loading to %p\n", v->load_addr);
649
650 if (relocate) {
651 for (i = 0; i < hdr->e_shnum; i++) {
652 void *dest;
653
654 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
655 continue;
656
657 dest = v->load_addr + sechdrs[i].sh_entsize;
658
659 if (sechdrs[i].sh_type != SHT_NOBITS)
660 memcpy(dest, (void *)sechdrs[i].sh_addr,
661 sechdrs[i].sh_size);
662 /* Update sh_addr to point to copy in image. */
663 sechdrs[i].sh_addr = (unsigned long)dest;
664
665 pr_debug(" section sh_name %s sh_addr 0x%x\n",
666 secstrings + sechdrs[i].sh_name,
667 sechdrs[i].sh_addr);
668 }
669
670 /* Fix up syms, so that st_value is a pointer to location. */
671 simplify_symbols(sechdrs, symindex, strtab, secstrings,
672 hdr->e_shnum, &mod);
673
674 /* Now do relocations. */
675 for (i = 1; i < hdr->e_shnum; i++) {
676 const char *strtab = (char *)sechdrs[strindex].sh_addr;
677 unsigned int info = sechdrs[i].sh_info;
678
679 /* Not a valid relocation section? */
680 if (info >= hdr->e_shnum)
681 continue;
682
683 /* Don't bother with non-allocated sections */
684 if (!(sechdrs[info].sh_flags & SHF_ALLOC))
685 continue;
686
687 if (sechdrs[i].sh_type == SHT_REL)
688 err = apply_relocations(sechdrs, strtab,
689 symindex, i, &mod);
690 else if (sechdrs[i].sh_type == SHT_RELA)
691 err = apply_relocate_add(sechdrs, strtab,
692 symindex, i, &mod);
693 if (err < 0)
694 return err;
695
696 }
697 } else {
698 struct elf_phdr *phdr = (struct elf_phdr *)
699 ((char *)hdr + hdr->e_phoff);
700
701 for (i = 0; i < hdr->e_phnum; i++) {
702 if (phdr->p_type == PT_LOAD) {
703 memcpy((void *)phdr->p_paddr,
704 (char *)hdr + phdr->p_offset,
705 phdr->p_filesz);
706 memset((void *)phdr->p_paddr + phdr->p_filesz,
707 0, phdr->p_memsz - phdr->p_filesz);
708 }
709 phdr++;
710 }
711
712 for (i = 0; i < hdr->e_shnum; i++) {
713 /* Internal symbols and strings. */
714 if (sechdrs[i].sh_type == SHT_SYMTAB) {
715 symindex = i;
716 strindex = sechdrs[i].sh_link;
717 strtab = (char *)hdr +
718 sechdrs[strindex].sh_offset;
719
720 /*
721 * mark symtab's address for when we try
722 * to find the magic symbols
723 */
724 sechdrs[i].sh_addr = (size_t) hdr +
725 sechdrs[i].sh_offset;
726 }
727 }
728 }
729
730 /* make sure it's physically written out */
731 flush_icache_range((unsigned long)v->load_addr,
732 (unsigned long)v->load_addr + v->len);
733
734 if ((find_vpe_symbols(v, sechdrs, symindex, strtab, &mod)) < 0) {
735 if (v->__start == 0) {
736 pr_warn("VPE loader: program does not contain a __start symbol\n");
737 return -ENOEXEC;
738 }
739
740 if (v->shared_ptr == NULL)
741 pr_warn("VPE loader: program does not contain vpe_shared symbol.\n"
742 " Unable to use AMVP (AP/SP) facilities.\n");
743 }
744
745 pr_info(" elf loaded\n");
746 return 0;
747 }
748
getcwd(char * buff,int size)749 static int getcwd(char *buff, int size)
750 {
751 mm_segment_t old_fs;
752 int ret;
753
754 old_fs = get_fs();
755 set_fs(KERNEL_DS);
756
757 ret = sys_getcwd(buff, size);
758
759 set_fs(old_fs);
760
761 return ret;
762 }
763
764 /* checks VPE is unused and gets ready to load program */
vpe_open(struct inode * inode,struct file * filp)765 static int vpe_open(struct inode *inode, struct file *filp)
766 {
767 enum vpe_state state;
768 struct vpe_notifications *notifier;
769 struct vpe *v;
770 int ret;
771
772 if (VPE_MODULE_MINOR != iminor(inode)) {
773 /* assume only 1 device at the moment. */
774 pr_warn("VPE loader: only vpe1 is supported\n");
775
776 return -ENODEV;
777 }
778
779 v = get_vpe(aprp_cpu_index());
780 if (v == NULL) {
781 pr_warn("VPE loader: unable to get vpe\n");
782
783 return -ENODEV;
784 }
785
786 state = xchg(&v->state, VPE_STATE_INUSE);
787 if (state != VPE_STATE_UNUSED) {
788 pr_debug("VPE loader: tc in use dumping regs\n");
789
790 list_for_each_entry(notifier, &v->notify, list)
791 notifier->stop(aprp_cpu_index());
792
793 release_progmem(v->load_addr);
794 cleanup_tc(get_tc(aprp_cpu_index()));
795 }
796
797 /* this of-course trashes what was there before... */
798 v->pbuffer = vmalloc(P_SIZE);
799 if (!v->pbuffer) {
800 pr_warn("VPE loader: unable to allocate memory\n");
801 return -ENOMEM;
802 }
803 v->plen = P_SIZE;
804 v->load_addr = NULL;
805 v->len = 0;
806
807 v->cwd[0] = 0;
808 ret = getcwd(v->cwd, VPE_PATH_MAX);
809 if (ret < 0)
810 pr_warn("VPE loader: open, getcwd returned %d\n", ret);
811
812 v->shared_ptr = NULL;
813 v->__start = 0;
814
815 return 0;
816 }
817
vpe_release(struct inode * inode,struct file * filp)818 static int vpe_release(struct inode *inode, struct file *filp)
819 {
820 struct vpe *v;
821 Elf_Ehdr *hdr;
822 int ret = 0;
823
824 v = get_vpe(aprp_cpu_index());
825 if (v == NULL)
826 return -ENODEV;
827
828 hdr = (Elf_Ehdr *) v->pbuffer;
829 if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) == 0) {
830 if ((vpe_elfload(v) >= 0) && vpe_run) {
831 vpe_run(v);
832 } else {
833 pr_warn("VPE loader: ELF load failed.\n");
834 ret = -ENOEXEC;
835 }
836 } else {
837 pr_warn("VPE loader: only elf files are supported\n");
838 ret = -ENOEXEC;
839 }
840
841 /* It's good to be able to run the SP and if it chokes have a look at
842 the /dev/rt?. But if we reset the pointer to the shared struct we
843 lose what has happened. So perhaps if garbage is sent to the vpe
844 device, use it as a trigger for the reset. Hopefully a nice
845 executable will be along shortly. */
846 if (ret < 0)
847 v->shared_ptr = NULL;
848
849 vfree(v->pbuffer);
850 v->plen = 0;
851
852 return ret;
853 }
854
vpe_write(struct file * file,const char __user * buffer,size_t count,loff_t * ppos)855 static ssize_t vpe_write(struct file *file, const char __user *buffer,
856 size_t count, loff_t *ppos)
857 {
858 size_t ret = count;
859 struct vpe *v;
860
861 if (iminor(file_inode(file)) != VPE_MODULE_MINOR)
862 return -ENODEV;
863
864 v = get_vpe(aprp_cpu_index());
865
866 if (v == NULL)
867 return -ENODEV;
868
869 if ((count + v->len) > v->plen) {
870 pr_warn("VPE loader: elf size too big. Perhaps strip uneeded symbols\n");
871 return -ENOMEM;
872 }
873
874 count -= copy_from_user(v->pbuffer + v->len, buffer, count);
875 if (!count)
876 return -EFAULT;
877
878 v->len += count;
879 return ret;
880 }
881
882 const struct file_operations vpe_fops = {
883 .owner = THIS_MODULE,
884 .open = vpe_open,
885 .release = vpe_release,
886 .write = vpe_write,
887 .llseek = noop_llseek,
888 };
889
vpe_get_shared(int index)890 void *vpe_get_shared(int index)
891 {
892 struct vpe *v = get_vpe(index);
893
894 if (v == NULL)
895 return NULL;
896
897 return v->shared_ptr;
898 }
899 EXPORT_SYMBOL(vpe_get_shared);
900
vpe_notify(int index,struct vpe_notifications * notify)901 int vpe_notify(int index, struct vpe_notifications *notify)
902 {
903 struct vpe *v = get_vpe(index);
904
905 if (v == NULL)
906 return -1;
907
908 list_add(¬ify->list, &v->notify);
909 return 0;
910 }
911 EXPORT_SYMBOL(vpe_notify);
912
vpe_getcwd(int index)913 char *vpe_getcwd(int index)
914 {
915 struct vpe *v = get_vpe(index);
916
917 if (v == NULL)
918 return NULL;
919
920 return v->cwd;
921 }
922 EXPORT_SYMBOL(vpe_getcwd);
923
924 module_init(vpe_module_init);
925 module_exit(vpe_module_exit);
926 MODULE_DESCRIPTION("MIPS VPE Loader");
927 MODULE_AUTHOR("Elizabeth Oldham, MIPS Technologies, Inc.");
928 MODULE_LICENSE("GPL");
929