module.c

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/*    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>
 *    Copyright (C) 2008 Helge Deller <[email protected]>
 *
 *
 *    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:
 *    - PLT stub handling
 *      On 32bit (and sometimes 64bit) and with big kernel modules like xfs or
 *      ipv6 the relocation types R_PARISC_PCREL17F and R_PARISC_PCREL22F may
 *      fail to reach their PLT stub if we only create one big stub array for
 *      all sections at the beginning of the core or init section.
 *      Instead we now insert individual PLT stub entries directly in front of
 *      of the code sections where the stubs are actually called.
 *      This reduces the distance between the PCREL location and the stub entry
 *      so that the relocations can be fulfilled.
 *      While calculating the final layout of the kernel module in memory, the
 *      kernel module loader calls arch_mod_section_prepend() to request the
 *      to be reserved amount of memory in front of each individual section.
 *
 *    - 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/mm.h>
#include <linux/slab.h>

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

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

#define RELOC_REACHABLE(val, bits) \
    (( ( !((val) & (1<<((bits)-1))) && ((val)>>(bits)) != 0 )  ||   \
         ( ((val) & (1<<((bits)-1))) && ((val)>>(bits)) != (((__typeof__(val))(~0))>>((bits)+2)))) ? \
    0 : 1)

#define CHECK_RELOC(val, bits) \
    if (!RELOC_REACHABLE(val, bits)) { \
        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.
 * To overcome this 14bit displacement with some kernel modules, we'll
 * use instead the unusal 16bit displacement method (see reassemble_16a)
 * which gives us a maximum positive displacement of 0x7fff, and as such
 * allows us to allocate up to 4095 GOT entries. */
#define MAX_GOTS    4095

/* 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);
}

#ifndef CONFIG_64BIT
struct got_entry {
    Elf32_Addr addr;
};

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

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 sign_unext(int x, int len)
{
    int len_ones;

    len_ones = (1 << len) - 1;
    return x & len_ones;
}

static inline int low_sign_unext(int x, int len)
{
    int sign, temp;

    sign = (x >> (len-1)) & 1;
    temp = sign_unext(x, len-1);
    return (temp << 1) | sign;
}

static inline int reassemble_14(int as14)
{
    return (((as14 & 0x1fff) << 1) |
        ((as14 & 0x2000) >> 13));
}

static inline int reassemble_16a(int as16)
{
    int s, t;

    /* Unusual 16-bit encoding, for wide mode only.  */
    t = (as16 << 1) & 0xffff;
    s = (as16 & 0x8000);
    return (t ^ s ^ (s >> 1)) | (s >> 15);
}


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;
    /* using RWX means less protection for modules, but it's
     * easier than trying to map the text, data, init_text and
     * init_data correctly */
    return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
                    GFP_KERNEL | __GFP_HIGHMEM,
                    PAGE_KERNEL_RWX, -1,
                    __builtin_return_address(0));
}

#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)
{
    kfree(mod->arch.section);
    mod->arch.section = NULL;

    vfree(module_region);
}

/* Additional bytes needed in front of individual sections */
unsigned int arch_mod_section_prepend(struct module *mod,
                      unsigned int section)
{
    /* size needed for all stubs of this section (including
     * one additional for correct alignment of the stubs) */
    return (mod->arch.section[section].stub_entries + 1)
        * sizeof(struct stub_entry);
}

#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, len;
    unsigned int i;

    len = hdr->e_shnum * sizeof(me->arch.section[0]);
    me->arch.section = kzalloc(len, GFP_KERNEL);
    if (!me->arch.section)
        return -ENOMEM;

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

        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);

        /* XXX: By sorting the relocs and finding duplicate entries
         *  we could reduce the number of necessary stubs and save
         *  some memory. */
        count = count_stubs(rels, nrels);
        if (!count)
            continue;

        /* so we need relocation stubs. reserve necessary memory. */
        /* sh_info gives the section for which we need to add stubs. */
        s = sechdrs[i].sh_info;

        /* each code section should only have one relocation section */
        WARN_ON(me->arch.section[s].stub_entries);

        /* store number of stubs we need for this section */
        me->arch.section[s].stub_entries += count;
    }

    /* 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->arch.got_max = gots;
    me->arch.fdesc_max = fdescs;

    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, Elf_Addr loc0, unsigned int targetsec)
{
    struct stub_entry *stub;
    int __maybe_unused d;

    /* initialize stub_offset to point in front of the section */
    if (!me->arch.section[targetsec].stub_offset) {
        loc0 -= (me->arch.section[targetsec].stub_entries + 1) *
                sizeof(struct stub_entry);
        /* get correct alignment for the stubs */
        loc0 = ALIGN(loc0, sizeof(struct stub_entry));
        me->arch.section[targetsec].stub_offset = loc0;
    }

    /* get address of stub entry */
    stub = (void *) me->arch.section[targetsec].stub_offset;
    me->arch.section[targetsec].stub_offset += sizeof(struct stub_entry);

    /* do not write outside available stub area */
    BUG_ON(0 == me->arch.section[targetsec].stub_entries--);


#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:
        d = get_got(me, value, addend);
        if (d <= 15) {
            /* Format 5 */
            stub->insns[0] = 0x0f6010db; /* ldd 0(%dp),%dp  */
            stub->insns[0] |= low_sign_unext(d, 5) << 16;
        } else {
            /* Format 3 */
            stub->insns[0] = 0x537b0000; /* ldd 0(%dp),%dp  */
            stub->insns[0] |= reassemble_16a(d);
        }
        stub->insns[1] = 0x53610020;    /* ldd 10(%dp),%r1  */
        stub->insns[2] = 0xe820d000;    /* bve (%r1)        */
        stub->insns[3] = 0x537b0030;    /* ldd 18(%dp),%dp  */
        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;
}

#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;
    Elf_Addr loc0;
    unsigned int targetsec = sechdrs[relsec].sh_info;
    //unsigned long dp = (unsigned long)$global$;
    register unsigned long dp asm ("r27");

    DEBUGP("Applying relocate section %u to %u\n", relsec,
           targetsec);
    for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
        /* This is where to make the change */
        loc = (void *)sechdrs[targetsec].sh_addr
              + rel[i].r_offset;
        /* This is the start of the target section */
        loc0 = sechdrs[targetsec].sh_addr;
        /* 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 */
            /* calculate direct call offset */
            val += addend;
            val = (val - dot - 8)/4;
            if (!RELOC_REACHABLE(val, 17)) {
                /* direct distance too far, create
                 * stub entry instead */
                val = get_stub(me, sym->st_value, addend,
                    ELF_STUB_DIRECT, loc0, targetsec);
                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 */
            /* calculate direct call offset */
            val += addend;
            val = (val - dot - 8)/4;
            if (!RELOC_REACHABLE(val, 22)) {
                /* direct distance too far, create
                 * stub entry instead */
                val = get_stub(me, sym->st_value, addend,
                    ELF_STUB_DIRECT, loc0, targetsec);
                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;
    Elf_Addr loc0;
    unsigned int targetsec = sechdrs[relsec].sh_info;

    DEBUGP("Applying relocate section %u to %u\n", relsec,
           targetsec);
    for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
        /* This is where to make the change */
        loc = (void *)sechdrs[targetsec].sh_addr
              + rel[i].r_offset;
        /* This is the start of the target section */
        loc0 = sechdrs[targetsec].sh_addr;
        /* 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);
            val += addend;
            /* can we reach it locally? */
            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 = (val - dot - 8)/4;
                if (!RELOC_REACHABLE(val, 22)) {
                    /* direct distance too far, create
                     * stub entry instead */
                    val = get_stub(me, sym->st_value,
                        addend, ELF_STUB_DIRECT,
                        loc0, targetsec);
                } else {
                    /* Ok, we can reach it directly. */
                    val = sym->st_value;
                    val += addend;
                }
            } else {
                val = sym->st_value;
                if (strncmp(strtab + sym->st_name, "$$", 2)
                    == 0)
                    val = get_stub(me, val, addend, ELF_STUB_MILLI,
                               loc0, targetsec);
                else
                    val = get_stub(me, val, addend, ELF_STUB_GOT,
                               loc0, targetsec);
            }
            DEBUGP("STUB FOR %s loc %lx, val %lx+%lx at %lx\n", 
                   strtab + sym->st_name, loc, sym->st_value,
                   addend, val);
            val = (val - dot - 8)/4;
            CHECK_RELOC(val, 22);
            *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("got entries used %ld, gots max %ld\n"
           "fdescs used %ld, fdescs max %ld\n",
           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_flags & 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;
    }

    kfree(me->arch.section);
    me->arch.section = NULL;

    /* 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 0;
}

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