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