linux/arch/parisc/kernel/module.c
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   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 * To overcome this 14bit displacement with some kernel modules, we'll
  91 * use instead the unusal 16bit displacement method (see reassemble_16a)
  92 * which gives us a maximum positive displacement of 0x7fff, and as such
  93 * allows us to allocate up to 4095 GOT entries. */
  94#define MAX_GOTS        4095
  95
  96/* three functions to determine where in the module core
  97 * or init pieces the location is */
  98static inline int in_init(struct module *me, void *loc)
  99{
 100        return (loc >= me->module_init &&
 101                loc <= (me->module_init + me->init_size));
 102}
 103
 104static inline int in_core(struct module *me, void *loc)
 105{
 106        return (loc >= me->module_core &&
 107                loc <= (me->module_core + me->core_size));
 108}
 109
 110static inline int in_local(struct module *me, void *loc)
 111{
 112        return in_init(me, loc) || in_core(me, loc);
 113}
 114
 115#ifndef CONFIG_64BIT
 116struct got_entry {
 117        Elf32_Addr addr;
 118};
 119
 120struct stub_entry {
 121        Elf32_Word insns[2]; /* each stub entry has two insns */
 122};
 123#else
 124struct got_entry {
 125        Elf64_Addr addr;
 126};
 127
 128struct stub_entry {
 129        Elf64_Word insns[4]; /* each stub entry has four insns */
 130};
 131#endif
 132
 133/* Field selection types defined by hppa */
 134#define rnd(x)                  (((x)+0x1000)&~0x1fff)
 135/* fsel: full 32 bits */
 136#define fsel(v,a)               ((v)+(a))
 137/* lsel: select left 21 bits */
 138#define lsel(v,a)               (((v)+(a))>>11)
 139/* rsel: select right 11 bits */
 140#define rsel(v,a)               (((v)+(a))&0x7ff)
 141/* lrsel with rounding of addend to nearest 8k */
 142#define lrsel(v,a)              (((v)+rnd(a))>>11)
 143/* rrsel with rounding of addend to nearest 8k */
 144#define rrsel(v,a)              ((((v)+rnd(a))&0x7ff)+((a)-rnd(a)))
 145
 146#define mask(x,sz)              ((x) & ~((1<<(sz))-1))
 147
 148
 149/* The reassemble_* functions prepare an immediate value for
 150   insertion into an opcode. pa-risc uses all sorts of weird bitfields
 151   in the instruction to hold the value.  */
 152static inline int sign_unext(int x, int len)
 153{
 154        int len_ones;
 155
 156        len_ones = (1 << len) - 1;
 157        return x & len_ones;
 158}
 159
 160static inline int low_sign_unext(int x, int len)
 161{
 162        int sign, temp;
 163
 164        sign = (x >> (len-1)) & 1;
 165        temp = sign_unext(x, len-1);
 166        return (temp << 1) | sign;
 167}
 168
 169static inline int reassemble_14(int as14)
 170{
 171        return (((as14 & 0x1fff) << 1) |
 172                ((as14 & 0x2000) >> 13));
 173}
 174
 175static inline int reassemble_16a(int as16)
 176{
 177        int s, t;
 178
 179        /* Unusual 16-bit encoding, for wide mode only.  */
 180        t = (as16 << 1) & 0xffff;
 181        s = (as16 & 0x8000);
 182        return (t ^ s ^ (s >> 1)) | (s >> 15);
 183}
 184
 185
 186static inline int reassemble_17(int as17)
 187{
 188        return (((as17 & 0x10000) >> 16) |
 189                ((as17 & 0x0f800) << 5) |
 190                ((as17 & 0x00400) >> 8) |
 191                ((as17 & 0x003ff) << 3));
 192}
 193
 194static inline int reassemble_21(int as21)
 195{
 196        return (((as21 & 0x100000) >> 20) |
 197                ((as21 & 0x0ffe00) >> 8) |
 198                ((as21 & 0x000180) << 7) |
 199                ((as21 & 0x00007c) << 14) |
 200                ((as21 & 0x000003) << 12));
 201}
 202
 203static inline int reassemble_22(int as22)
 204{
 205        return (((as22 & 0x200000) >> 21) |
 206                ((as22 & 0x1f0000) << 5) |
 207                ((as22 & 0x00f800) << 5) |
 208                ((as22 & 0x000400) >> 8) |
 209                ((as22 & 0x0003ff) << 3));
 210}
 211
 212void *module_alloc(unsigned long size)
 213{
 214        if (size == 0)
 215                return NULL;
 216        return vmalloc(size);
 217}
 218
 219#ifndef CONFIG_64BIT
 220static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
 221{
 222        return 0;
 223}
 224
 225static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
 226{
 227        return 0;
 228}
 229
 230static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
 231{
 232        unsigned long cnt = 0;
 233
 234        for (; n > 0; n--, rela++)
 235        {
 236                switch (ELF32_R_TYPE(rela->r_info)) {
 237                        case R_PARISC_PCREL17F:
 238                        case R_PARISC_PCREL22F:
 239                                cnt++;
 240                }
 241        }
 242
 243        return cnt;
 244}
 245#else
 246static inline unsigned long count_gots(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_LTOFF21L:
 254                        case R_PARISC_LTOFF14R:
 255                        case R_PARISC_PCREL22F:
 256                                cnt++;
 257                }
 258        }
 259
 260        return cnt;
 261}
 262
 263static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
 264{
 265        unsigned long cnt = 0;
 266
 267        for (; n > 0; n--, rela++)
 268        {
 269                switch (ELF64_R_TYPE(rela->r_info)) {
 270                        case R_PARISC_FPTR64:
 271                                cnt++;
 272                }
 273        }
 274
 275        return cnt;
 276}
 277
 278static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
 279{
 280        unsigned long cnt = 0;
 281
 282        for (; n > 0; n--, rela++)
 283        {
 284                switch (ELF64_R_TYPE(rela->r_info)) {
 285                        case R_PARISC_PCREL22F:
 286                                cnt++;
 287                }
 288        }
 289
 290        return cnt;
 291}
 292#endif
 293
 294
 295/* Free memory returned from module_alloc */
 296void module_free(struct module *mod, void *module_region)
 297{
 298        kfree(mod->arch.section);
 299        mod->arch.section = NULL;
 300
 301        vfree(module_region);
 302}
 303
 304/* Additional bytes needed in front of individual sections */
 305unsigned int arch_mod_section_prepend(struct module *mod,
 306                                      unsigned int section)
 307{
 308        /* size needed for all stubs of this section (including
 309         * one additional for correct alignment of the stubs) */
 310        return (mod->arch.section[section].stub_entries + 1)
 311                * sizeof(struct stub_entry);
 312}
 313
 314#define CONST 
 315int module_frob_arch_sections(CONST Elf_Ehdr *hdr,
 316                              CONST Elf_Shdr *sechdrs,
 317                              CONST char *secstrings,
 318                              struct module *me)
 319{
 320        unsigned long gots = 0, fdescs = 0, len;
 321        unsigned int i;
 322
 323        len = hdr->e_shnum * sizeof(me->arch.section[0]);
 324        me->arch.section = kzalloc(len, GFP_KERNEL);
 325        if (!me->arch.section)
 326                return -ENOMEM;
 327
 328        for (i = 1; i < hdr->e_shnum; i++) {
 329                const Elf_Rela *rels = (void *)sechdrs[i].sh_addr;
 330                unsigned long nrels = sechdrs[i].sh_size / sizeof(*rels);
 331                unsigned int count, s;
 332
 333                if (strncmp(secstrings + sechdrs[i].sh_name,
 334                            ".PARISC.unwind", 14) == 0)
 335                        me->arch.unwind_section = i;
 336
 337                if (sechdrs[i].sh_type != SHT_RELA)
 338                        continue;
 339
 340                /* some of these are not relevant for 32-bit/64-bit
 341                 * we leave them here to make the code common. the
 342                 * compiler will do its thing and optimize out the
 343                 * stuff we don't need
 344                 */
 345                gots += count_gots(rels, nrels);
 346                fdescs += count_fdescs(rels, nrels);
 347
 348                /* XXX: By sorting the relocs and finding duplicate entries
 349                 *  we could reduce the number of necessary stubs and save
 350                 *  some memory. */
 351                count = count_stubs(rels, nrels);
 352                if (!count)
 353                        continue;
 354
 355                /* so we need relocation stubs. reserve necessary memory. */
 356                /* sh_info gives the section for which we need to add stubs. */
 357                s = sechdrs[i].sh_info;
 358
 359                /* each code section should only have one relocation section */
 360                WARN_ON(me->arch.section[s].stub_entries);
 361
 362                /* store number of stubs we need for this section */
 363                me->arch.section[s].stub_entries += count;
 364        }
 365
 366        /* align things a bit */
 367        me->core_size = ALIGN(me->core_size, 16);
 368        me->arch.got_offset = me->core_size;
 369        me->core_size += gots * sizeof(struct got_entry);
 370
 371        me->core_size = ALIGN(me->core_size, 16);
 372        me->arch.fdesc_offset = me->core_size;
 373        me->core_size += fdescs * sizeof(Elf_Fdesc);
 374
 375        me->arch.got_max = gots;
 376        me->arch.fdesc_max = fdescs;
 377
 378        return 0;
 379}
 380
 381#ifdef CONFIG_64BIT
 382static Elf64_Word get_got(struct module *me, unsigned long value, long addend)
 383{
 384        unsigned int i;
 385        struct got_entry *got;
 386
 387        value += addend;
 388
 389        BUG_ON(value == 0);
 390
 391        got = me->module_core + me->arch.got_offset;
 392        for (i = 0; got[i].addr; i++)
 393                if (got[i].addr == value)
 394                        goto out;
 395
 396        BUG_ON(++me->arch.got_count > me->arch.got_max);
 397
 398        got[i].addr = value;
 399 out:
 400        DEBUGP("GOT ENTRY %d[%x] val %lx\n", i, i*sizeof(struct got_entry),
 401               value);
 402        return i * sizeof(struct got_entry);
 403}
 404#endif /* CONFIG_64BIT */
 405
 406#ifdef CONFIG_64BIT
 407static Elf_Addr get_fdesc(struct module *me, unsigned long value)
 408{
 409        Elf_Fdesc *fdesc = me->module_core + me->arch.fdesc_offset;
 410
 411        if (!value) {
 412                printk(KERN_ERR "%s: zero OPD requested!\n", me->name);
 413                return 0;
 414        }
 415
 416        /* Look for existing fdesc entry. */
 417        while (fdesc->addr) {
 418                if (fdesc->addr == value)
 419                        return (Elf_Addr)fdesc;
 420                fdesc++;
 421        }
 422
 423        BUG_ON(++me->arch.fdesc_count > me->arch.fdesc_max);
 424
 425        /* Create new one */
 426        fdesc->addr = value;
 427        fdesc->gp = (Elf_Addr)me->module_core + me->arch.got_offset;
 428        return (Elf_Addr)fdesc;
 429}
 430#endif /* CONFIG_64BIT */
 431
 432enum elf_stub_type {
 433        ELF_STUB_GOT,
 434        ELF_STUB_MILLI,
 435        ELF_STUB_DIRECT,
 436};
 437
 438static Elf_Addr get_stub(struct module *me, unsigned long value, long addend,
 439        enum elf_stub_type stub_type, Elf_Addr loc0, unsigned int targetsec)
 440{
 441        struct stub_entry *stub;
 442        int __maybe_unused d;
 443
 444        /* initialize stub_offset to point in front of the section */
 445        if (!me->arch.section[targetsec].stub_offset) {
 446                loc0 -= (me->arch.section[targetsec].stub_entries + 1) *
 447                                sizeof(struct stub_entry);
 448                /* get correct alignment for the stubs */
 449                loc0 = ALIGN(loc0, sizeof(struct stub_entry));
 450                me->arch.section[targetsec].stub_offset = loc0;
 451        }
 452
 453        /* get address of stub entry */
 454        stub = (void *) me->arch.section[targetsec].stub_offset;
 455        me->arch.section[targetsec].stub_offset += sizeof(struct stub_entry);
 456
 457        /* do not write outside available stub area */
 458        BUG_ON(0 == me->arch.section[targetsec].stub_entries--);
 459
 460
 461#ifndef CONFIG_64BIT
 462/* for 32-bit the stub looks like this:
 463 *      ldil L'XXX,%r1
 464 *      be,n R'XXX(%sr4,%r1)
 465 */
 466        //value = *(unsigned long *)((value + addend) & ~3); /* why? */
 467
 468        stub->insns[0] = 0x20200000;    /* ldil L'XXX,%r1       */
 469        stub->insns[1] = 0xe0202002;    /* be,n R'XXX(%sr4,%r1) */
 470
 471        stub->insns[0] |= reassemble_21(lrsel(value, addend));
 472        stub->insns[1] |= reassemble_17(rrsel(value, addend) / 4);
 473
 474#else
 475/* for 64-bit we have three kinds of stubs:
 476 * for normal function calls:
 477 *      ldd 0(%dp),%dp
 478 *      ldd 10(%dp), %r1
 479 *      bve (%r1)
 480 *      ldd 18(%dp), %dp
 481 *
 482 * for millicode:
 483 *      ldil 0, %r1
 484 *      ldo 0(%r1), %r1
 485 *      ldd 10(%r1), %r1
 486 *      bve,n (%r1)
 487 *
 488 * for direct branches (jumps between different section of the
 489 * same module):
 490 *      ldil 0, %r1
 491 *      ldo 0(%r1), %r1
 492 *      bve,n (%r1)
 493 */
 494        switch (stub_type) {
 495        case ELF_STUB_GOT:
 496                d = get_got(me, value, addend);
 497                if (d <= 15) {
 498                        /* Format 5 */
 499                        stub->insns[0] = 0x0f6010db; /* ldd 0(%dp),%dp  */
 500                        stub->insns[0] |= low_sign_unext(d, 5) << 16;
 501                } else {
 502                        /* Format 3 */
 503                        stub->insns[0] = 0x537b0000; /* ldd 0(%dp),%dp  */
 504                        stub->insns[0] |= reassemble_16a(d);
 505                }
 506                stub->insns[1] = 0x53610020;    /* ldd 10(%dp),%r1      */
 507                stub->insns[2] = 0xe820d000;    /* bve (%r1)            */
 508                stub->insns[3] = 0x537b0030;    /* ldd 18(%dp),%dp      */
 509                break;
 510        case ELF_STUB_MILLI:
 511                stub->insns[0] = 0x20200000;    /* ldil 0,%r1           */
 512                stub->insns[1] = 0x34210000;    /* ldo 0(%r1), %r1      */
 513                stub->insns[2] = 0x50210020;    /* ldd 10(%r1),%r1      */
 514                stub->insns[3] = 0xe820d002;    /* bve,n (%r1)          */
 515
 516                stub->insns[0] |= reassemble_21(lrsel(value, addend));
 517                stub->insns[1] |= reassemble_14(rrsel(value, addend));
 518                break;
 519        case ELF_STUB_DIRECT:
 520                stub->insns[0] = 0x20200000;    /* ldil 0,%r1           */
 521                stub->insns[1] = 0x34210000;    /* ldo 0(%r1), %r1      */
 522                stub->insns[2] = 0xe820d002;    /* bve,n (%r1)          */
 523
 524                stub->insns[0] |= reassemble_21(lrsel(value, addend));
 525                stub->insns[1] |= reassemble_14(rrsel(value, addend));
 526                break;
 527        }
 528
 529#endif
 530
 531        return (Elf_Addr)stub;
 532}
 533
 534int apply_relocate(Elf_Shdr *sechdrs,
 535                   const char *strtab,
 536                   unsigned int symindex,
 537                   unsigned int relsec,
 538                   struct module *me)
 539{
 540        /* parisc should not need this ... */
 541        printk(KERN_ERR "module %s: RELOCATION unsupported\n",
 542               me->name);
 543        return -ENOEXEC;
 544}
 545
 546#ifndef CONFIG_64BIT
 547int apply_relocate_add(Elf_Shdr *sechdrs,
 548                       const char *strtab,
 549                       unsigned int symindex,
 550                       unsigned int relsec,
 551                       struct module *me)
 552{
 553        int i;
 554        Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
 555        Elf32_Sym *sym;
 556        Elf32_Word *loc;
 557        Elf32_Addr val;
 558        Elf32_Sword addend;
 559        Elf32_Addr dot;
 560        Elf_Addr loc0;
 561        unsigned int targetsec = sechdrs[relsec].sh_info;
 562        //unsigned long dp = (unsigned long)$global$;
 563        register unsigned long dp asm ("r27");
 564
 565        DEBUGP("Applying relocate section %u to %u\n", relsec,
 566               targetsec);
 567        for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
 568                /* This is where to make the change */
 569                loc = (void *)sechdrs[targetsec].sh_addr
 570                      + rel[i].r_offset;
 571                /* This is the start of the target section */
 572                loc0 = sechdrs[targetsec].sh_addr;
 573                /* This is the symbol it is referring to */
 574                sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
 575                        + ELF32_R_SYM(rel[i].r_info);
 576                if (!sym->st_value) {
 577                        printk(KERN_WARNING "%s: Unknown symbol %s\n",
 578                               me->name, strtab + sym->st_name);
 579                        return -ENOENT;
 580                }
 581                //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
 582                dot =  (Elf32_Addr)loc & ~0x03;
 583
 584                val = sym->st_value;
 585                addend = rel[i].r_addend;
 586
 587#if 0
 588#define r(t) ELF32_R_TYPE(rel[i].r_info)==t ? #t :
 589                DEBUGP("Symbol %s loc 0x%x val 0x%x addend 0x%x: %s\n",
 590                        strtab + sym->st_name,
 591                        (uint32_t)loc, val, addend,
 592                        r(R_PARISC_PLABEL32)
 593                        r(R_PARISC_DIR32)
 594                        r(R_PARISC_DIR21L)
 595                        r(R_PARISC_DIR14R)
 596                        r(R_PARISC_SEGREL32)
 597                        r(R_PARISC_DPREL21L)
 598                        r(R_PARISC_DPREL14R)
 599                        r(R_PARISC_PCREL17F)
 600                        r(R_PARISC_PCREL22F)
 601                        "UNKNOWN");
 602#undef r
 603#endif
 604
 605                switch (ELF32_R_TYPE(rel[i].r_info)) {
 606                case R_PARISC_PLABEL32:
 607                        /* 32-bit function address */
 608                        /* no function descriptors... */
 609                        *loc = fsel(val, addend);
 610                        break;
 611                case R_PARISC_DIR32:
 612                        /* direct 32-bit ref */
 613                        *loc = fsel(val, addend);
 614                        break;
 615                case R_PARISC_DIR21L:
 616                        /* left 21 bits of effective address */
 617                        val = lrsel(val, addend);
 618                        *loc = mask(*loc, 21) | reassemble_21(val);
 619                        break;
 620                case R_PARISC_DIR14R:
 621                        /* right 14 bits of effective address */
 622                        val = rrsel(val, addend);
 623                        *loc = mask(*loc, 14) | reassemble_14(val);
 624                        break;
 625                case R_PARISC_SEGREL32:
 626                        /* 32-bit segment relative address */
 627                        /* See note about special handling of SEGREL32 at
 628                         * the beginning of this file.
 629                         */
 630                        *loc = fsel(val, addend); 
 631                        break;
 632                case R_PARISC_DPREL21L:
 633                        /* left 21 bit of relative address */
 634                        val = lrsel(val - dp, addend);
 635                        *loc = mask(*loc, 21) | reassemble_21(val);
 636                        break;
 637                case R_PARISC_DPREL14R:
 638                        /* right 14 bit of relative address */
 639                        val = rrsel(val - dp, addend);
 640                        *loc = mask(*loc, 14) | reassemble_14(val);
 641                        break;
 642                case R_PARISC_PCREL17F:
 643                        /* 17-bit PC relative address */
 644                        /* calculate direct call offset */
 645                        val += addend;
 646                        val = (val - dot - 8)/4;
 647                        if (!RELOC_REACHABLE(val, 17)) {
 648                                /* direct distance too far, create
 649                                 * stub entry instead */
 650                                val = get_stub(me, sym->st_value, addend,
 651                                        ELF_STUB_DIRECT, loc0, targetsec);
 652                                val = (val - dot - 8)/4;
 653                                CHECK_RELOC(val, 17);
 654                        }
 655                        *loc = (*loc & ~0x1f1ffd) | reassemble_17(val);
 656                        break;
 657                case R_PARISC_PCREL22F:
 658                        /* 22-bit PC relative address; only defined for pa20 */
 659                        /* calculate direct call offset */
 660                        val += addend;
 661                        val = (val - dot - 8)/4;
 662                        if (!RELOC_REACHABLE(val, 22)) {
 663                                /* direct distance too far, create
 664                                 * stub entry instead */
 665                                val = get_stub(me, sym->st_value, addend,
 666                                        ELF_STUB_DIRECT, loc0, targetsec);
 667                                val = (val - dot - 8)/4;
 668                                CHECK_RELOC(val, 22);
 669                        }
 670                        *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
 671                        break;
 672
 673                default:
 674                        printk(KERN_ERR "module %s: Unknown relocation: %u\n",
 675                               me->name, ELF32_R_TYPE(rel[i].r_info));
 676                        return -ENOEXEC;
 677                }
 678        }
 679
 680        return 0;
 681}
 682
 683#else
 684int apply_relocate_add(Elf_Shdr *sechdrs,
 685                       const char *strtab,
 686                       unsigned int symindex,
 687                       unsigned int relsec,
 688                       struct module *me)
 689{
 690        int i;
 691        Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr;
 692        Elf64_Sym *sym;
 693        Elf64_Word *loc;
 694        Elf64_Xword *loc64;
 695        Elf64_Addr val;
 696        Elf64_Sxword addend;
 697        Elf64_Addr dot;
 698        Elf_Addr loc0;
 699        unsigned int targetsec = sechdrs[relsec].sh_info;
 700
 701        DEBUGP("Applying relocate section %u to %u\n", relsec,
 702               targetsec);
 703        for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
 704                /* This is where to make the change */
 705                loc = (void *)sechdrs[targetsec].sh_addr
 706                      + rel[i].r_offset;
 707                /* This is the start of the target section */
 708                loc0 = sechdrs[targetsec].sh_addr;
 709                /* This is the symbol it is referring to */
 710                sym = (Elf64_Sym *)sechdrs[symindex].sh_addr
 711                        + ELF64_R_SYM(rel[i].r_info);
 712                if (!sym->st_value) {
 713                        printk(KERN_WARNING "%s: Unknown symbol %s\n",
 714                               me->name, strtab + sym->st_name);
 715                        return -ENOENT;
 716                }
 717                //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
 718                dot = (Elf64_Addr)loc & ~0x03;
 719                loc64 = (Elf64_Xword *)loc;
 720
 721                val = sym->st_value;
 722                addend = rel[i].r_addend;
 723
 724#if 0
 725#define r(t) ELF64_R_TYPE(rel[i].r_info)==t ? #t :
 726                printk("Symbol %s loc %p val 0x%Lx addend 0x%Lx: %s\n",
 727                        strtab + sym->st_name,
 728                        loc, val, addend,
 729                        r(R_PARISC_LTOFF14R)
 730                        r(R_PARISC_LTOFF21L)
 731                        r(R_PARISC_PCREL22F)
 732                        r(R_PARISC_DIR64)
 733                        r(R_PARISC_SEGREL32)
 734                        r(R_PARISC_FPTR64)
 735                        "UNKNOWN");
 736#undef r
 737#endif
 738
 739                switch (ELF64_R_TYPE(rel[i].r_info)) {
 740                case R_PARISC_LTOFF21L:
 741                        /* LT-relative; left 21 bits */
 742                        val = get_got(me, val, addend);
 743                        DEBUGP("LTOFF21L Symbol %s loc %p val %lx\n",
 744                               strtab + sym->st_name,
 745                               loc, val);
 746                        val = lrsel(val, 0);
 747                        *loc = mask(*loc, 21) | reassemble_21(val);
 748                        break;
 749                case R_PARISC_LTOFF14R:
 750                        /* L(ltoff(val+addend)) */
 751                        /* LT-relative; right 14 bits */
 752                        val = get_got(me, val, addend);
 753                        val = rrsel(val, 0);
 754                        DEBUGP("LTOFF14R Symbol %s loc %p val %lx\n",
 755                               strtab + sym->st_name,
 756                               loc, val);
 757                        *loc = mask(*loc, 14) | reassemble_14(val);
 758                        break;
 759                case R_PARISC_PCREL22F:
 760                        /* PC-relative; 22 bits */
 761                        DEBUGP("PCREL22F Symbol %s loc %p val %lx\n",
 762                               strtab + sym->st_name,
 763                               loc, val);
 764                        val += addend;
 765                        /* can we reach it locally? */
 766                        if (in_local(me, (void *)val)) {
 767                                /* this is the case where the symbol is local
 768                                 * to the module, but in a different section,
 769                                 * so stub the jump in case it's more than 22
 770                                 * bits away */
 771                                val = (val - dot - 8)/4;
 772                                if (!RELOC_REACHABLE(val, 22)) {
 773                                        /* direct distance too far, create
 774                                         * stub entry instead */
 775                                        val = get_stub(me, sym->st_value,
 776                                                addend, ELF_STUB_DIRECT,
 777                                                loc0, targetsec);
 778                                } else {
 779                                        /* Ok, we can reach it directly. */
 780                                        val = sym->st_value;
 781                                        val += addend;
 782                                }
 783                        } else {
 784                                val = sym->st_value;
 785                                if (strncmp(strtab + sym->st_name, "$$", 2)
 786                                    == 0)
 787                                        val = get_stub(me, val, addend, ELF_STUB_MILLI,
 788                                                       loc0, targetsec);
 789                                else
 790                                        val = get_stub(me, val, addend, ELF_STUB_GOT,
 791                                                       loc0, targetsec);
 792                        }
 793                        DEBUGP("STUB FOR %s loc %lx, val %lx+%lx at %lx\n", 
 794                               strtab + sym->st_name, loc, sym->st_value,
 795                               addend, val);
 796                        val = (val - dot - 8)/4;
 797                        CHECK_RELOC(val, 22);
 798                        *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
 799                        break;
 800                case R_PARISC_DIR64:
 801                        /* 64-bit effective address */
 802                        *loc64 = val + addend;
 803                        break;
 804                case R_PARISC_SEGREL32:
 805                        /* 32-bit segment relative address */
 806                        /* See note about special handling of SEGREL32 at
 807                         * the beginning of this file.
 808                         */
 809                        *loc = fsel(val, addend); 
 810                        break;
 811                case R_PARISC_FPTR64:
 812                        /* 64-bit function address */
 813                        if(in_local(me, (void *)(val + addend))) {
 814                                *loc64 = get_fdesc(me, val+addend);
 815                                DEBUGP("FDESC for %s at %p points to %lx\n",
 816                                       strtab + sym->st_name, *loc64,
 817                                       ((Elf_Fdesc *)*loc64)->addr);
 818                        } else {
 819                                /* if the symbol is not local to this
 820                                 * module then val+addend is a pointer
 821                                 * to the function descriptor */
 822                                DEBUGP("Non local FPTR64 Symbol %s loc %p val %lx\n",
 823                                       strtab + sym->st_name,
 824                                       loc, val);
 825                                *loc64 = val + addend;
 826                        }
 827                        break;
 828
 829                default:
 830                        printk(KERN_ERR "module %s: Unknown relocation: %Lu\n",
 831                               me->name, ELF64_R_TYPE(rel[i].r_info));
 832                        return -ENOEXEC;
 833                }
 834        }
 835        return 0;
 836}
 837#endif
 838
 839static void
 840register_unwind_table(struct module *me,
 841                      const Elf_Shdr *sechdrs)
 842{
 843        unsigned char *table, *end;
 844        unsigned long gp;
 845
 846        if (!me->arch.unwind_section)
 847                return;
 848
 849        table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr;
 850        end = table + sechdrs[me->arch.unwind_section].sh_size;
 851        gp = (Elf_Addr)me->module_core + me->arch.got_offset;
 852
 853        DEBUGP("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n",
 854               me->arch.unwind_section, table, end, gp);
 855        me->arch.unwind = unwind_table_add(me->name, 0, gp, table, end);
 856}
 857
 858static void
 859deregister_unwind_table(struct module *me)
 860{
 861        if (me->arch.unwind)
 862                unwind_table_remove(me->arch.unwind);
 863}
 864
 865int module_finalize(const Elf_Ehdr *hdr,
 866                    const Elf_Shdr *sechdrs,
 867                    struct module *me)
 868{
 869        int i;
 870        unsigned long nsyms;
 871        const char *strtab = NULL;
 872        Elf_Sym *newptr, *oldptr;
 873        Elf_Shdr *symhdr = NULL;
 874#ifdef DEBUG
 875        Elf_Fdesc *entry;
 876        u32 *addr;
 877
 878        entry = (Elf_Fdesc *)me->init;
 879        printk("FINALIZE, ->init FPTR is %p, GP %lx ADDR %lx\n", entry,
 880               entry->gp, entry->addr);
 881        addr = (u32 *)entry->addr;
 882        printk("INSNS: %x %x %x %x\n",
 883               addr[0], addr[1], addr[2], addr[3]);
 884        printk("got entries used %ld, gots max %ld\n"
 885               "fdescs used %ld, fdescs max %ld\n",
 886               me->arch.got_count, me->arch.got_max,
 887               me->arch.fdesc_count, me->arch.fdesc_max);
 888#endif
 889
 890        register_unwind_table(me, sechdrs);
 891
 892        /* haven't filled in me->symtab yet, so have to find it
 893         * ourselves */
 894        for (i = 1; i < hdr->e_shnum; i++) {
 895                if(sechdrs[i].sh_type == SHT_SYMTAB
 896                   && (sechdrs[i].sh_flags & SHF_ALLOC)) {
 897                        int strindex = sechdrs[i].sh_link;
 898                        /* FIXME: AWFUL HACK
 899                         * The cast is to drop the const from
 900                         * the sechdrs pointer */
 901                        symhdr = (Elf_Shdr *)&sechdrs[i];
 902                        strtab = (char *)sechdrs[strindex].sh_addr;
 903                        break;
 904                }
 905        }
 906
 907        DEBUGP("module %s: strtab %p, symhdr %p\n",
 908               me->name, strtab, symhdr);
 909
 910        if(me->arch.got_count > MAX_GOTS) {
 911                printk(KERN_ERR "%s: Global Offset Table overflow (used %ld, allowed %d)\n",
 912                                me->name, me->arch.got_count, MAX_GOTS);
 913                return -EINVAL;
 914        }
 915
 916        kfree(me->arch.section);
 917        me->arch.section = NULL;
 918
 919        /* no symbol table */
 920        if(symhdr == NULL)
 921                return 0;
 922
 923        oldptr = (void *)symhdr->sh_addr;
 924        newptr = oldptr + 1;    /* we start counting at 1 */
 925        nsyms = symhdr->sh_size / sizeof(Elf_Sym);
 926        DEBUGP("OLD num_symtab %lu\n", nsyms);
 927
 928        for (i = 1; i < nsyms; i++) {
 929                oldptr++;       /* note, count starts at 1 so preincrement */
 930                if(strncmp(strtab + oldptr->st_name,
 931                              ".L", 2) == 0)
 932                        continue;
 933
 934                if(newptr != oldptr)
 935                        *newptr++ = *oldptr;
 936                else
 937                        newptr++;
 938
 939        }
 940        nsyms = newptr - (Elf_Sym *)symhdr->sh_addr;
 941        DEBUGP("NEW num_symtab %lu\n", nsyms);
 942        symhdr->sh_size = nsyms * sizeof(Elf_Sym);
 943        return module_bug_finalize(hdr, sechdrs, me);
 944}
 945
 946void module_arch_cleanup(struct module *mod)
 947{
 948        deregister_unwind_table(mod);
 949        module_bug_cleanup(mod);
 950}
 951