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module.c

/*    Kernel dynamically loadable module help for PARISC.
 *
 *    The best reference for this stuff is probably the Processor-
 *    Specific ELF Supplement for PA-RISC:
 *        http://ftp.parisc-linux.org/docs/arch/elf-pa-hp.pdf
 *
 *    Linux/PA-RISC Project (http://www.parisc-linux.org/)
 *    Copyright (C) 2003 Randolph Chung <tausq at debian . org>
 *
 *
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 *
 *    Notes:
 *    - SEGREL32 handling
 *      We are not doing SEGREL32 handling correctly. According to the ABI, we
 *      should do a value offset, like this:
 *                if (in_init(me, (void *)val))
 *                      val -= (uint32_t)me->module_init;
 *                else
 *                      val -= (uint32_t)me->module_core;
 *    However, SEGREL32 is used only for PARISC unwind entries, and we want
 *    those entries to have an absolute address, and not just an offset.
 *
 *    The unwind table mechanism has the ability to specify an offset for 
 *    the unwind table; however, because we split off the init functions into
 *    a different piece of memory, it is not possible to do this using a 
 *    single offset. Instead, we use the above hack for now.
 */

#include <linux/moduleloader.h>
#include <linux/elf.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/bug.h>
#include <linux/uaccess.h>

#include <asm/sections.h>
#include <asm/unwind.h>

#if 0
#define DEBUGP printk
#else
#define DEBUGP(fmt...)
#endif

#define CHECK_RELOC(val, bits) \
      if ( ( !((val) & (1<<((bits)-1))) && ((val)>>(bits)) != 0 )  ||   \
           ( ((val) & (1<<((bits)-1))) && ((val)>>(bits)) != (((__typeof__(val))(~0))>>((bits)+2)))) { \
            printk(KERN_ERR "module %s relocation of symbol %s is out of range (0x%lx in %d bits)\n", \
            me->name, strtab + sym->st_name, (unsigned long)val, bits); \
            return -ENOEXEC;              \
      }

/* Maximum number of GOT entries. We use a long displacement ldd from
 * the bottom of the table, which has a maximum signed displacement of
 * 0x3fff; however, since we're only going forward, this becomes
 * 0x1fff, and thus, since each GOT entry is 8 bytes long we can have
 * at most 1023 entries */
#define MAX_GOTS  1023

/* three functions to determine where in the module core
 * or init pieces the location is */
static inline int in_init(struct module *me, void *loc)
{
      return (loc >= me->module_init &&
            loc <= (me->module_init + me->init_size));
}

static inline int in_core(struct module *me, void *loc)
{
      return (loc >= me->module_core &&
            loc <= (me->module_core + me->core_size));
}

static inline int in_local(struct module *me, void *loc)
{
      return in_init(me, loc) || in_core(me, loc);
}

static inline int in_local_section(struct module *me, void *loc, void *dot)
{
      return (in_init(me, loc) && in_init(me, dot)) ||
            (in_core(me, loc) && in_core(me, dot));
}


#ifndef CONFIG_64BIT
struct got_entry {
      Elf32_Addr addr;
};

#define Elf_Fdesc Elf32_Fdesc

struct stub_entry {
      Elf32_Word insns[2]; /* each stub entry has two insns */
};
#else
struct got_entry {
      Elf64_Addr addr;
};

#define Elf_Fdesc Elf64_Fdesc

struct stub_entry {
      Elf64_Word insns[4]; /* each stub entry has four insns */
};
#endif

/* Field selection types defined by hppa */
#define rnd(x)                (((x)+0x1000)&~0x1fff)
/* fsel: full 32 bits */
#define fsel(v,a)       ((v)+(a))
/* lsel: select left 21 bits */
#define lsel(v,a)       (((v)+(a))>>11)
/* rsel: select right 11 bits */
#define rsel(v,a)       (((v)+(a))&0x7ff)
/* lrsel with rounding of addend to nearest 8k */
#define lrsel(v,a)            (((v)+rnd(a))>>11)
/* rrsel with rounding of addend to nearest 8k */
#define rrsel(v,a)            ((((v)+rnd(a))&0x7ff)+((a)-rnd(a)))

#define mask(x,sz)            ((x) & ~((1<<(sz))-1))


/* The reassemble_* functions prepare an immediate value for
   insertion into an opcode. pa-risc uses all sorts of weird bitfields
   in the instruction to hold the value.  */
static inline int reassemble_14(int as14)
{
      return (((as14 & 0x1fff) << 1) |
            ((as14 & 0x2000) >> 13));
}

static inline int reassemble_17(int as17)
{
      return (((as17 & 0x10000) >> 16) |
            ((as17 & 0x0f800) << 5) |
            ((as17 & 0x00400) >> 8) |
            ((as17 & 0x003ff) << 3));
}

static inline int reassemble_21(int as21)
{
      return (((as21 & 0x100000) >> 20) |
            ((as21 & 0x0ffe00) >> 8) |
            ((as21 & 0x000180) << 7) |
            ((as21 & 0x00007c) << 14) |
            ((as21 & 0x000003) << 12));
}

static inline int reassemble_22(int as22)
{
      return (((as22 & 0x200000) >> 21) |
            ((as22 & 0x1f0000) << 5) |
            ((as22 & 0x00f800) << 5) |
            ((as22 & 0x000400) >> 8) |
            ((as22 & 0x0003ff) << 3));
}

void *module_alloc(unsigned long size)
{
      if (size == 0)
            return NULL;
      return vmalloc(size);
}

#ifndef CONFIG_64BIT
static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
{
      return 0;
}

static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
{
      return 0;
}

static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
{
      unsigned long cnt = 0;

      for (; n > 0; n--, rela++)
      {
            switch (ELF32_R_TYPE(rela->r_info)) {
                  case R_PARISC_PCREL17F:
                  case R_PARISC_PCREL22F:
                        cnt++;
            }
      }

      return cnt;
}
#else
static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
{
      unsigned long cnt = 0;

      for (; n > 0; n--, rela++)
      {
            switch (ELF64_R_TYPE(rela->r_info)) {
                  case R_PARISC_LTOFF21L:
                  case R_PARISC_LTOFF14R:
                  case R_PARISC_PCREL22F:
                        cnt++;
            }
      }

      return cnt;
}

static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
{
      unsigned long cnt = 0;

      for (; n > 0; n--, rela++)
      {
            switch (ELF64_R_TYPE(rela->r_info)) {
                  case R_PARISC_FPTR64:
                        cnt++;
            }
      }

      return cnt;
}

static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
{
      unsigned long cnt = 0;

      for (; n > 0; n--, rela++)
      {
            switch (ELF64_R_TYPE(rela->r_info)) {
                  case R_PARISC_PCREL22F:
                        cnt++;
            }
      }

      return cnt;
}
#endif


/* Free memory returned from module_alloc */
void module_free(struct module *mod, void *module_region)
{
      vfree(module_region);
      /* FIXME: If module_region == mod->init_region, trim exception
           table entries. */
}

#define CONST 
int module_frob_arch_sections(CONST Elf_Ehdr *hdr,
                        CONST Elf_Shdr *sechdrs,
                        CONST char *secstrings,
                        struct module *me)
{
      unsigned long gots = 0, fdescs = 0, stubs = 0, init_stubs = 0;
      unsigned int i;

      for (i = 1; i < hdr->e_shnum; i++) {
            const Elf_Rela *rels = (void *)hdr + sechdrs[i].sh_offset;
            unsigned long nrels = sechdrs[i].sh_size / sizeof(*rels);

            if (strncmp(secstrings + sechdrs[i].sh_name,
                      ".PARISC.unwind", 14) == 0)
                  me->arch.unwind_section = i;

            if (sechdrs[i].sh_type != SHT_RELA)
                  continue;

            /* some of these are not relevant for 32-bit/64-bit
             * we leave them here to make the code common. the
             * compiler will do its thing and optimize out the
             * stuff we don't need
             */
            gots += count_gots(rels, nrels);
            fdescs += count_fdescs(rels, nrels);
            if(strncmp(secstrings + sechdrs[i].sh_name,
                     ".rela.init", 10) == 0)
                  init_stubs += count_stubs(rels, nrels);
            else
                  stubs += count_stubs(rels, nrels);
      }

      /* align things a bit */
      me->core_size = ALIGN(me->core_size, 16);
      me->arch.got_offset = me->core_size;
      me->core_size += gots * sizeof(struct got_entry);

      me->core_size = ALIGN(me->core_size, 16);
      me->arch.fdesc_offset = me->core_size;
      me->core_size += fdescs * sizeof(Elf_Fdesc);

      me->core_size = ALIGN(me->core_size, 16);
      me->arch.stub_offset = me->core_size;
      me->core_size += stubs * sizeof(struct stub_entry);

      me->init_size = ALIGN(me->init_size, 16);
      me->arch.init_stub_offset = me->init_size;
      me->init_size += init_stubs * sizeof(struct stub_entry);

      me->arch.got_max = gots;
      me->arch.fdesc_max = fdescs;
      me->arch.stub_max = stubs;
      me->arch.init_stub_max = init_stubs;

      return 0;
}

#ifdef CONFIG_64BIT
static Elf64_Word get_got(struct module *me, unsigned long value, long addend)
{
      unsigned int i;
      struct got_entry *got;

      value += addend;

      BUG_ON(value == 0);

      got = me->module_core + me->arch.got_offset;
      for (i = 0; got[i].addr; i++)
            if (got[i].addr == value)
                  goto out;

      BUG_ON(++me->arch.got_count > me->arch.got_max);

      got[i].addr = value;
 out:
      DEBUGP("GOT ENTRY %d[%x] val %lx\n", i, i*sizeof(struct got_entry),
             value);
      return i * sizeof(struct got_entry);
}
#endif /* CONFIG_64BIT */

#ifdef CONFIG_64BIT
static Elf_Addr get_fdesc(struct module *me, unsigned long value)
{
      Elf_Fdesc *fdesc = me->module_core + me->arch.fdesc_offset;

      if (!value) {
            printk(KERN_ERR "%s: zero OPD requested!\n", me->name);
            return 0;
      }

      /* Look for existing fdesc entry. */
      while (fdesc->addr) {
            if (fdesc->addr == value)
                  return (Elf_Addr)fdesc;
            fdesc++;
      }

      BUG_ON(++me->arch.fdesc_count > me->arch.fdesc_max);

      /* Create new one */
      fdesc->addr = value;
      fdesc->gp = (Elf_Addr)me->module_core + me->arch.got_offset;
      return (Elf_Addr)fdesc;
}
#endif /* CONFIG_64BIT */

enum elf_stub_type {
      ELF_STUB_GOT,
      ELF_STUB_MILLI,
      ELF_STUB_DIRECT,
};

static Elf_Addr get_stub(struct module *me, unsigned long value, long addend,
      enum elf_stub_type stub_type, int init_section)
{
      unsigned long i;
      struct stub_entry *stub;

      if(init_section) {
            i = me->arch.init_stub_count++;
            BUG_ON(me->arch.init_stub_count > me->arch.init_stub_max);
            stub = me->module_init + me->arch.init_stub_offset + 
                  i * sizeof(struct stub_entry);
      } else {
            i = me->arch.stub_count++;
            BUG_ON(me->arch.stub_count > me->arch.stub_max);
            stub = me->module_core + me->arch.stub_offset + 
                  i * sizeof(struct stub_entry);
      }

#ifndef CONFIG_64BIT
/* for 32-bit the stub looks like this:
 *    ldil L'XXX,%r1
 *    be,n R'XXX(%sr4,%r1)
 */
      //value = *(unsigned long *)((value + addend) & ~3); /* why? */

      stub->insns[0] = 0x20200000;  /* ldil L'XXX,%r1 */
      stub->insns[1] = 0xe0202002;  /* be,n R'XXX(%sr4,%r1) */

      stub->insns[0] |= reassemble_21(lrsel(value, addend));
      stub->insns[1] |= reassemble_17(rrsel(value, addend) / 4);

#else
/* for 64-bit we have three kinds of stubs:
 * for normal function calls:
 *    ldd 0(%dp),%dp
 *    ldd 10(%dp), %r1
 *    bve (%r1)
 *    ldd 18(%dp), %dp
 *
 * for millicode:
 *    ldil 0, %r1
 *    ldo 0(%r1), %r1
 *    ldd 10(%r1), %r1
 *    bve,n (%r1)
 *
 * for direct branches (jumps between different section of the
 * same module):
 *    ldil 0, %r1
 *    ldo 0(%r1), %r1
 *    bve,n (%r1)
 */
      switch (stub_type) {
      case ELF_STUB_GOT:
            stub->insns[0] = 0x537b0000;  /* ldd 0(%dp),%dp */
            stub->insns[1] = 0x53610020;  /* ldd 10(%dp),%r1      */
            stub->insns[2] = 0xe820d000;  /* bve (%r1)            */
            stub->insns[3] = 0x537b0030;  /* ldd 18(%dp),%dp      */

            stub->insns[0] |= reassemble_14(get_got(me, value, addend) & 0x3fff);
            break;
      case ELF_STUB_MILLI:
            stub->insns[0] = 0x20200000;  /* ldil 0,%r1           */
            stub->insns[1] = 0x34210000;  /* ldo 0(%r1), %r1      */
            stub->insns[2] = 0x50210020;  /* ldd 10(%r1),%r1      */
            stub->insns[3] = 0xe820d002;  /* bve,n (%r1)          */

            stub->insns[0] |= reassemble_21(lrsel(value, addend));
            stub->insns[1] |= reassemble_14(rrsel(value, addend));
            break;
      case ELF_STUB_DIRECT:
            stub->insns[0] = 0x20200000;    /* ldil 0,%r1           */
            stub->insns[1] = 0x34210000;    /* ldo 0(%r1), %r1      */
            stub->insns[2] = 0xe820d002;    /* bve,n (%r1)          */

            stub->insns[0] |= reassemble_21(lrsel(value, addend));
            stub->insns[1] |= reassemble_14(rrsel(value, addend));
            break;
      }

#endif

      return (Elf_Addr)stub;
}

int apply_relocate(Elf_Shdr *sechdrs,
               const char *strtab,
               unsigned int symindex,
               unsigned int relsec,
               struct module *me)
{
      /* parisc should not need this ... */
      printk(KERN_ERR "module %s: RELOCATION unsupported\n",
             me->name);
      return -ENOEXEC;
}

#ifndef CONFIG_64BIT
int apply_relocate_add(Elf_Shdr *sechdrs,
                   const char *strtab,
                   unsigned int symindex,
                   unsigned int relsec,
                   struct module *me)
{
      int i;
      Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
      Elf32_Sym *sym;
      Elf32_Word *loc;
      Elf32_Addr val;
      Elf32_Sword addend;
      Elf32_Addr dot;
      //unsigned long dp = (unsigned long)$global$;
      register unsigned long dp asm ("r27");

      DEBUGP("Applying relocate section %u to %u\n", relsec,
             sechdrs[relsec].sh_info);
      for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
            /* This is where to make the change */
            loc = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
                  + rel[i].r_offset;
            /* This is the symbol it is referring to */
            sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
                  + ELF32_R_SYM(rel[i].r_info);
            if (!sym->st_value) {
                  printk(KERN_WARNING "%s: Unknown symbol %s\n",
                         me->name, strtab + sym->st_name);
                  return -ENOENT;
            }
            //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
            dot =  (Elf32_Addr)loc & ~0x03;

            val = sym->st_value;
            addend = rel[i].r_addend;

#if 0
#define r(t) ELF32_R_TYPE(rel[i].r_info)==t ? #t :
            DEBUGP("Symbol %s loc 0x%x val 0x%x addend 0x%x: %s\n",
                  strtab + sym->st_name,
                  (uint32_t)loc, val, addend,
                  r(R_PARISC_PLABEL32)
                  r(R_PARISC_DIR32)
                  r(R_PARISC_DIR21L)
                  r(R_PARISC_DIR14R)
                  r(R_PARISC_SEGREL32)
                  r(R_PARISC_DPREL21L)
                  r(R_PARISC_DPREL14R)
                  r(R_PARISC_PCREL17F)
                  r(R_PARISC_PCREL22F)
                  "UNKNOWN");
#undef r
#endif

            switch (ELF32_R_TYPE(rel[i].r_info)) {
            case R_PARISC_PLABEL32:
                  /* 32-bit function address */
                  /* no function descriptors... */
                  *loc = fsel(val, addend);
                  break;
            case R_PARISC_DIR32:
                  /* direct 32-bit ref */
                  *loc = fsel(val, addend);
                  break;
            case R_PARISC_DIR21L:
                  /* left 21 bits of effective address */
                  val = lrsel(val, addend);
                  *loc = mask(*loc, 21) | reassemble_21(val);
                  break;
            case R_PARISC_DIR14R:
                  /* right 14 bits of effective address */
                  val = rrsel(val, addend);
                  *loc = mask(*loc, 14) | reassemble_14(val);
                  break;
            case R_PARISC_SEGREL32:
                  /* 32-bit segment relative address */
                  /* See note about special handling of SEGREL32 at
                   * the beginning of this file.
                   */
                  *loc = fsel(val, addend); 
                  break;
            case R_PARISC_DPREL21L:
                  /* left 21 bit of relative address */
                  val = lrsel(val - dp, addend);
                  *loc = mask(*loc, 21) | reassemble_21(val);
                  break;
            case R_PARISC_DPREL14R:
                  /* right 14 bit of relative address */
                  val = rrsel(val - dp, addend);
                  *loc = mask(*loc, 14) | reassemble_14(val);
                  break;
            case R_PARISC_PCREL17F:
                  /* 17-bit PC relative address */
                  val = get_stub(me, val, addend, ELF_STUB_GOT, in_init(me, loc));
                  val = (val - dot - 8)/4;
                  CHECK_RELOC(val, 17)
                  *loc = (*loc & ~0x1f1ffd) | reassemble_17(val);
                  break;
            case R_PARISC_PCREL22F:
                  /* 22-bit PC relative address; only defined for pa20 */
                  val = get_stub(me, val, addend, ELF_STUB_GOT, in_init(me, loc));
                  DEBUGP("STUB FOR %s loc %lx+%lx at %lx\n", 
                         strtab + sym->st_name, (unsigned long)loc, addend, 
                         val)
                  val = (val - dot - 8)/4;
                  CHECK_RELOC(val, 22);
                  *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
                  break;

            default:
                  printk(KERN_ERR "module %s: Unknown relocation: %u\n",
                         me->name, ELF32_R_TYPE(rel[i].r_info));
                  return -ENOEXEC;
            }
      }

      return 0;
}

#else
int apply_relocate_add(Elf_Shdr *sechdrs,
                   const char *strtab,
                   unsigned int symindex,
                   unsigned int relsec,
                   struct module *me)
{
      int i;
      Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr;
      Elf64_Sym *sym;
      Elf64_Word *loc;
      Elf64_Xword *loc64;
      Elf64_Addr val;
      Elf64_Sxword addend;
      Elf64_Addr dot;

      DEBUGP("Applying relocate section %u to %u\n", relsec,
             sechdrs[relsec].sh_info);
      for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
            /* This is where to make the change */
            loc = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
                  + rel[i].r_offset;
            /* This is the symbol it is referring to */
            sym = (Elf64_Sym *)sechdrs[symindex].sh_addr
                  + ELF64_R_SYM(rel[i].r_info);
            if (!sym->st_value) {
                  printk(KERN_WARNING "%s: Unknown symbol %s\n",
                         me->name, strtab + sym->st_name);
                  return -ENOENT;
            }
            //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
            dot = (Elf64_Addr)loc & ~0x03;
            loc64 = (Elf64_Xword *)loc;

            val = sym->st_value;
            addend = rel[i].r_addend;

#if 0
#define r(t) ELF64_R_TYPE(rel[i].r_info)==t ? #t :
            printk("Symbol %s loc %p val 0x%Lx addend 0x%Lx: %s\n",
                  strtab + sym->st_name,
                  loc, val, addend,
                  r(R_PARISC_LTOFF14R)
                  r(R_PARISC_LTOFF21L)
                  r(R_PARISC_PCREL22F)
                  r(R_PARISC_DIR64)
                  r(R_PARISC_SEGREL32)
                  r(R_PARISC_FPTR64)
                  "UNKNOWN");
#undef r
#endif

            switch (ELF64_R_TYPE(rel[i].r_info)) {
            case R_PARISC_LTOFF21L:
                  /* LT-relative; left 21 bits */
                  val = get_got(me, val, addend);
                  DEBUGP("LTOFF21L Symbol %s loc %p val %lx\n",
                         strtab + sym->st_name,
                         loc, val);
                  val = lrsel(val, 0);
                  *loc = mask(*loc, 21) | reassemble_21(val);
                  break;
            case R_PARISC_LTOFF14R:
                  /* L(ltoff(val+addend)) */
                  /* LT-relative; right 14 bits */
                  val = get_got(me, val, addend);
                  val = rrsel(val, 0);
                  DEBUGP("LTOFF14R Symbol %s loc %p val %lx\n",
                         strtab + sym->st_name,
                         loc, val);
                  *loc = mask(*loc, 14) | reassemble_14(val);
                  break;
            case R_PARISC_PCREL22F:
                  /* PC-relative; 22 bits */
                  DEBUGP("PCREL22F Symbol %s loc %p val %lx\n",
                         strtab + sym->st_name,
                         loc, val);
                  /* can we reach it locally? */
                  if(!in_local_section(me, (void *)val, (void *)dot)) {

                        if (in_local(me, (void *)val))
                              /* this is the case where the
                               * symbol is local to the
                               * module, but in a different
                               * section, so stub the jump
                               * in case it's more than 22
                               * bits away */
                              val = get_stub(me, val, addend, ELF_STUB_DIRECT,
                                           in_init(me, loc));
                        else if (strncmp(strtab + sym->st_name, "$$", 2)
                            == 0)
                              val = get_stub(me, val, addend, ELF_STUB_MILLI,
                                           in_init(me, loc));
                        else
                              val = get_stub(me, val, addend, ELF_STUB_GOT,
                                           in_init(me, loc));
                  }
                  DEBUGP("STUB FOR %s loc %lx, val %lx+%lx at %lx\n", 
                         strtab + sym->st_name, loc, sym->st_value,
                         addend, val);
                  /* FIXME: local symbols work as long as the
                   * core and init pieces aren't separated too
                   * far.  If this is ever broken, you will trip
                   * the check below.  The way to fix it would
                   * be to generate local stubs to go between init
                   * and core */
                  if((Elf64_Sxword)(val - dot - 8) > 0x800000 -1 ||
                     (Elf64_Sxword)(val - dot - 8) < -0x800000) {
                        printk(KERN_ERR "Module %s, symbol %s is out of range for PCREL22F relocation\n",
                               me->name, strtab + sym->st_name);
                        return -ENOEXEC;
                  }
                  val = (val - dot - 8)/4;
                  *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
                  break;
            case R_PARISC_DIR64:
                  /* 64-bit effective address */
                  *loc64 = val + addend;
                  break;
            case R_PARISC_SEGREL32:
                  /* 32-bit segment relative address */
                  /* See note about special handling of SEGREL32 at
                   * the beginning of this file.
                   */
                  *loc = fsel(val, addend); 
                  break;
            case R_PARISC_FPTR64:
                  /* 64-bit function address */
                  if(in_local(me, (void *)(val + addend))) {
                        *loc64 = get_fdesc(me, val+addend);
                        DEBUGP("FDESC for %s at %p points to %lx\n",
                               strtab + sym->st_name, *loc64,
                               ((Elf_Fdesc *)*loc64)->addr);
                  } else {
                        /* if the symbol is not local to this
                         * module then val+addend is a pointer
                         * to the function descriptor */
                        DEBUGP("Non local FPTR64 Symbol %s loc %p val %lx\n",
                               strtab + sym->st_name,
                               loc, val);
                        *loc64 = val + addend;
                  }
                  break;

            default:
                  printk(KERN_ERR "module %s: Unknown relocation: %Lu\n",
                         me->name, ELF64_R_TYPE(rel[i].r_info));
                  return -ENOEXEC;
            }
      }
      return 0;
}
#endif

static void
register_unwind_table(struct module *me,
                  const Elf_Shdr *sechdrs)
{
      unsigned char *table, *end;
      unsigned long gp;

      if (!me->arch.unwind_section)
            return;

      table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr;
      end = table + sechdrs[me->arch.unwind_section].sh_size;
      gp = (Elf_Addr)me->module_core + me->arch.got_offset;

      DEBUGP("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n",
             me->arch.unwind_section, table, end, gp);
      me->arch.unwind = unwind_table_add(me->name, 0, gp, table, end);
}

static void
deregister_unwind_table(struct module *me)
{
      if (me->arch.unwind)
            unwind_table_remove(me->arch.unwind);
}

int module_finalize(const Elf_Ehdr *hdr,
                const Elf_Shdr *sechdrs,
                struct module *me)
{
      int i;
      unsigned long nsyms;
      const char *strtab = NULL;
      Elf_Sym *newptr, *oldptr;
      Elf_Shdr *symhdr = NULL;
#ifdef DEBUG
      Elf_Fdesc *entry;
      u32 *addr;

      entry = (Elf_Fdesc *)me->init;
      printk("FINALIZE, ->init FPTR is %p, GP %lx ADDR %lx\n", entry,
             entry->gp, entry->addr);
      addr = (u32 *)entry->addr;
      printk("INSNS: %x %x %x %x\n",
             addr[0], addr[1], addr[2], addr[3]);
      printk("stubs used %ld, stubs max %ld\n"
             "init_stubs used %ld, init stubs max %ld\n"
             "got entries used %ld, gots max %ld\n"
             "fdescs used %ld, fdescs max %ld\n",
             me->arch.stub_count, me->arch.stub_max,
             me->arch.init_stub_count, me->arch.init_stub_max,
             me->arch.got_count, me->arch.got_max,
             me->arch.fdesc_count, me->arch.fdesc_max);
#endif

      register_unwind_table(me, sechdrs);

      /* haven't filled in me->symtab yet, so have to find it
       * ourselves */
      for (i = 1; i < hdr->e_shnum; i++) {
            if(sechdrs[i].sh_type == SHT_SYMTAB
               && (sechdrs[i].sh_type & SHF_ALLOC)) {
                  int strindex = sechdrs[i].sh_link;
                  /* FIXME: AWFUL HACK
                   * The cast is to drop the const from
                   * the sechdrs pointer */
                  symhdr = (Elf_Shdr *)&sechdrs[i];
                  strtab = (char *)sechdrs[strindex].sh_addr;
                  break;
            }
      }

      DEBUGP("module %s: strtab %p, symhdr %p\n",
             me->name, strtab, symhdr);

      if(me->arch.got_count > MAX_GOTS) {
            printk(KERN_ERR "%s: Global Offset Table overflow (used %ld, allowed %d)\n",
                        me->name, me->arch.got_count, MAX_GOTS);
            return -EINVAL;
      }
      
      /* no symbol table */
      if(symhdr == NULL)
            return 0;

      oldptr = (void *)symhdr->sh_addr;
      newptr = oldptr + 1;    /* we start counting at 1 */
      nsyms = symhdr->sh_size / sizeof(Elf_Sym);
      DEBUGP("OLD num_symtab %lu\n", nsyms);

      for (i = 1; i < nsyms; i++) {
            oldptr++;   /* note, count starts at 1 so preincrement */
            if(strncmp(strtab + oldptr->st_name,
                        ".L", 2) == 0)
                  continue;

            if(newptr != oldptr)
                  *newptr++ = *oldptr;
            else
                  newptr++;

      }
      nsyms = newptr - (Elf_Sym *)symhdr->sh_addr;
      DEBUGP("NEW num_symtab %lu\n", nsyms);
      symhdr->sh_size = nsyms * sizeof(Elf_Sym);
      return module_bug_finalize(hdr, sechdrs, me);
}

void module_arch_cleanup(struct module *mod)
{
      deregister_unwind_table(mod);
      module_bug_cleanup(mod);
}

#ifdef CONFIG_64BIT
void *dereference_function_descriptor(void *ptr)
{
      Elf64_Fdesc *desc = ptr;
      void *p;

      if (!probe_kernel_address(&desc->addr, p))
            ptr = p;
      return ptr;
}
#endif

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