Archipelago » qemu

/* This is the Linux kernel elf-loading code, ported into user space */

#include <stdio.h>

#include <sys/types.h>

#include <fcntl.h>

#include <errno.h>

#include <unistd.h>

#include <sys/mman.h>

#include <stdlib.h>

#include <string.h>

#include "qemu.h"

#include "disas.h"

#ifdef __powerpc64__

#undef ARCH_DLINFO

#undef ELF_PLATFORM

#undef ELF_HWCAP

#undef ELF_CLASS

#undef ELF_DATA

#undef ELF_ARCH

#endif

/* from personality.h */

/*

 * Flags for bug emulation.

 *

 * These occupy the top three bytes.

 */

enum {

        ADDR_NO_RANDOMIZE =         0x0040000,        /* disable randomization of VA space */

        FDPIC_FUNCPTRS =        0x0080000,        /* userspace function ptrs point to descriptors

                                                 * (signal handling)

                                                 */

        MMAP_PAGE_ZERO =        0x0100000,

        ADDR_COMPAT_LAYOUT =        0x0200000,

        READ_IMPLIES_EXEC =        0x0400000,

        ADDR_LIMIT_32BIT =        0x0800000,

        SHORT_INODE =                0x1000000,

        WHOLE_SECONDS =                0x2000000,

        STICKY_TIMEOUTS        =        0x4000000,

        ADDR_LIMIT_3GB =         0x8000000,

};

/*

 * Personality types.

 *

 * These go in the low byte.  Avoid using the top bit, it will

 * conflict with error returns.

 */

enum {

        PER_LINUX =                0x0000,

        PER_LINUX_32BIT =        0x0000 | ADDR_LIMIT_32BIT,

        PER_LINUX_FDPIC =        0x0000 | FDPIC_FUNCPTRS,

        PER_SVR4 =                0x0001 | STICKY_TIMEOUTS | MMAP_PAGE_ZERO,

        PER_SVR3 =                0x0002 | STICKY_TIMEOUTS | SHORT_INODE,

        PER_SCOSVR3 =                0x0003 | STICKY_TIMEOUTS |

                                         WHOLE_SECONDS | SHORT_INODE,

        PER_OSR5 =                0x0003 | STICKY_TIMEOUTS | WHOLE_SECONDS,

        PER_WYSEV386 =                0x0004 | STICKY_TIMEOUTS | SHORT_INODE,

        PER_ISCR4 =                0x0005 | STICKY_TIMEOUTS,

        PER_BSD =                0x0006,

        PER_SUNOS =                0x0006 | STICKY_TIMEOUTS,

        PER_XENIX =                0x0007 | STICKY_TIMEOUTS | SHORT_INODE,

        PER_LINUX32 =                0x0008,

        PER_LINUX32_3GB =        0x0008 | ADDR_LIMIT_3GB,

        PER_IRIX32 =                0x0009 | STICKY_TIMEOUTS,/* IRIX5 32-bit */

        PER_IRIXN32 =                0x000a | STICKY_TIMEOUTS,/* IRIX6 new 32-bit */

        PER_IRIX64 =                0x000b | STICKY_TIMEOUTS,/* IRIX6 64-bit */

        PER_RISCOS =                0x000c,

        PER_SOLARIS =                0x000d | STICKY_TIMEOUTS,

        PER_UW7 =                0x000e | STICKY_TIMEOUTS | MMAP_PAGE_ZERO,

        PER_OSF4 =                0x000f,                         /* OSF/1 v4 */

        PER_HPUX =                0x0010,

        PER_MASK =                0x00ff,

};

/*

 * Return the base personality without flags.

 */

#define personality(pers)        (pers & PER_MASK)

/* this flag is uneffective under linux too, should be deleted */

#ifndef MAP_DENYWRITE

#define MAP_DENYWRITE 0

#endif

/* should probably go in elf.h */

#ifndef ELIBBAD

#define ELIBBAD 80

#endif

#ifdef TARGET_I386

#define ELF_PLATFORM get_elf_platform()

static const char *get_elf_platform(void)

{

    static char elf_platform[] = "i386";

    int family = (thread_env->cpuid_version >> 8) & 0xff;

    if (family > 6)

        family = 6;

    if (family >= 3)

        elf_platform[1] = '0' + family;

    return elf_platform;

}

#define ELF_HWCAP get_elf_hwcap()

static uint32_t get_elf_hwcap(void)

{

  return thread_env->cpuid_features;

}

#ifdef TARGET_X86_64

#define ELF_START_MMAP 0x2aaaaab000ULL

#define elf_check_arch(x) ( ((x) == ELF_ARCH) )

#define ELF_CLASS      ELFCLASS64

#define ELF_DATA       ELFDATA2LSB

#define ELF_ARCH       EM_X86_64

static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)

{

    regs->rax = 0;

    regs->rsp = infop->start_stack;

    regs->rip = infop->entry;

}

#else

#define ELF_START_MMAP 0x80000000

/*

 * This is used to ensure we don't load something for the wrong architecture.

 */

#define elf_check_arch(x) ( ((x) == EM_386) || ((x) == EM_486) )

/*

 * These are used to set parameters in the core dumps.

 */

#define ELF_CLASS        ELFCLASS32

#define ELF_DATA        ELFDATA2LSB

#define ELF_ARCH        EM_386

static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)

{

    regs->esp = infop->start_stack;

    regs->eip = infop->entry;

    /* SVR4/i386 ABI (pages 3-31, 3-32) says that when the program

       starts %edx contains a pointer to a function which might be

       registered using `atexit'.  This provides a mean for the

       dynamic linker to call DT_FINI functions for shared libraries

       that have been loaded before the code runs.

       A value of 0 tells we have no such handler.  */

    regs->edx = 0;

}

#endif

#define USE_ELF_CORE_DUMP

#define ELF_EXEC_PAGESIZE        4096

#endif

#ifdef TARGET_ARM

#define ELF_START_MMAP 0x80000000

#define elf_check_arch(x) ( (x) == EM_ARM )

#define ELF_CLASS        ELFCLASS32

#ifdef TARGET_WORDS_BIGENDIAN

#define ELF_DATA        ELFDATA2MSB

#else

#define ELF_DATA        ELFDATA2LSB

#endif

#define ELF_ARCH        EM_ARM

static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)

{

    abi_long stack = infop->start_stack;

    memset(regs, 0, sizeof(*regs));

    regs->ARM_cpsr = 0x10;

    if (infop->entry & 1)

      regs->ARM_cpsr |= CPSR_T;

    regs->ARM_pc = infop->entry & 0xfffffffe;

    regs->ARM_sp = infop->start_stack;

    /* FIXME - what to for failure of get_user()? */

    get_user_ual(regs->ARM_r2, stack + 8); /* envp */

    get_user_ual(regs->ARM_r1, stack + 4); /* envp */

    /* XXX: it seems that r0 is zeroed after ! */

    regs->ARM_r0 = 0;

    /* For uClinux PIC binaries.  */

    /* XXX: Linux does this only on ARM with no MMU (do we care ?) */

    regs->ARM_r10 = infop->start_data;

}

#define USE_ELF_CORE_DUMP

#define ELF_EXEC_PAGESIZE        4096

enum

{

  ARM_HWCAP_ARM_SWP       = 1 << 0,

  ARM_HWCAP_ARM_HALF      = 1 << 1,

  ARM_HWCAP_ARM_THUMB     = 1 << 2,

  ARM_HWCAP_ARM_26BIT     = 1 << 3,

  ARM_HWCAP_ARM_FAST_MULT = 1 << 4,

  ARM_HWCAP_ARM_FPA       = 1 << 5,

  ARM_HWCAP_ARM_VFP       = 1 << 6,

  ARM_HWCAP_ARM_EDSP      = 1 << 7,

};

#define ELF_HWCAP (ARM_HWCAP_ARM_SWP | ARM_HWCAP_ARM_HALF              \

                    | ARM_HWCAP_ARM_THUMB | ARM_HWCAP_ARM_FAST_MULT     \

                    | ARM_HWCAP_ARM_FPA | ARM_HWCAP_ARM_VFP)

#endif

#ifdef TARGET_SPARC

#ifdef TARGET_SPARC64

#define ELF_START_MMAP 0x80000000

#ifndef TARGET_ABI32

#define elf_check_arch(x) ( (x) == EM_SPARCV9 || (x) == EM_SPARC32PLUS )

#else

#define elf_check_arch(x) ( (x) == EM_SPARC32PLUS || (x) == EM_SPARC )

#endif

#define ELF_CLASS   ELFCLASS64

#define ELF_DATA    ELFDATA2MSB

#define ELF_ARCH    EM_SPARCV9

#define STACK_BIAS                2047

static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)

{

#ifndef TARGET_ABI32

    regs->tstate = 0;

#endif

    regs->pc = infop->entry;

    regs->npc = regs->pc + 4;

    regs->y = 0;

#ifdef TARGET_ABI32

    regs->u_regs[14] = infop->start_stack - 16 * 4;

#else

    if (personality(infop->personality) == PER_LINUX32)

        regs->u_regs[14] = infop->start_stack - 16 * 4;

    else

        regs->u_regs[14] = infop->start_stack - 16 * 8 - STACK_BIAS;

#endif

}

#else

#define ELF_START_MMAP 0x80000000

#define elf_check_arch(x) ( (x) == EM_SPARC )

#define ELF_CLASS   ELFCLASS32

#define ELF_DATA    ELFDATA2MSB

#define ELF_ARCH    EM_SPARC

static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)

{

    regs->psr = 0;

    regs->pc = infop->entry;

    regs->npc = regs->pc + 4;

    regs->y = 0;

    regs->u_regs[14] = infop->start_stack - 16 * 4;

}

#endif

#endif

#ifdef TARGET_PPC

#define ELF_START_MMAP 0x80000000

#if defined(TARGET_PPC64) && !defined(TARGET_ABI32)

#define elf_check_arch(x) ( (x) == EM_PPC64 )

#define ELF_CLASS        ELFCLASS64

#else

#define elf_check_arch(x) ( (x) == EM_PPC )

#define ELF_CLASS        ELFCLASS32

#endif

#ifdef TARGET_WORDS_BIGENDIAN

#define ELF_DATA        ELFDATA2MSB

#else

#define ELF_DATA        ELFDATA2LSB

#endif

#define ELF_ARCH        EM_PPC

/*

 * We need to put in some extra aux table entries to tell glibc what

 * the cache block size is, so it can use the dcbz instruction safely.

 */

#define AT_DCACHEBSIZE          19

#define AT_ICACHEBSIZE          20

#define AT_UCACHEBSIZE          21

/* A special ignored type value for PPC, for glibc compatibility.  */

#define AT_IGNOREPPC            22

/*

 * The requirements here are:

 * - keep the final alignment of sp (sp & 0xf)

 * - make sure the 32-bit value at the first 16 byte aligned position of

 *   AUXV is greater than 16 for glibc compatibility.

 *   AT_IGNOREPPC is used for that.

 * - for compatibility with glibc ARCH_DLINFO must always be defined on PPC,

 *   even if DLINFO_ARCH_ITEMS goes to zero or is undefined.

 */

#define DLINFO_ARCH_ITEMS       5

#define ARCH_DLINFO                                                     \

do {                                                                    \

        NEW_AUX_ENT(AT_DCACHEBSIZE, 0x20);                              \

        NEW_AUX_ENT(AT_ICACHEBSIZE, 0x20);                              \

        NEW_AUX_ENT(AT_UCACHEBSIZE, 0);                                 \

        /*                                                              \

         * Now handle glibc compatibility.                              \

         */                                                             \

        NEW_AUX_ENT(AT_IGNOREPPC, AT_IGNOREPPC);                        \

        NEW_AUX_ENT(AT_IGNOREPPC, AT_IGNOREPPC);                        \

 } while (0)

static inline void init_thread(struct target_pt_regs *_regs, struct image_info *infop)

{

    abi_ulong pos = infop->start_stack;

    abi_ulong tmp;

#if defined(TARGET_PPC64) && !defined(TARGET_ABI32)

    abi_ulong entry, toc;

#endif

    _regs->gpr[1] = infop->start_stack;

#if defined(TARGET_PPC64) && !defined(TARGET_ABI32)

    entry = ldq_raw(infop->entry) + infop->load_addr;

    toc = ldq_raw(infop->entry + 8) + infop->load_addr;

    _regs->gpr[2] = toc;

    infop->entry = entry;

#endif

    _regs->nip = infop->entry;

    /* Note that isn't exactly what regular kernel does

     * but this is what the ABI wants and is needed to allow

     * execution of PPC BSD programs.

     */

    /* FIXME - what to for failure of get_user()? */

    get_user_ual(_regs->gpr[3], pos);

    pos += sizeof(abi_ulong);

    _regs->gpr[4] = pos;

    for (tmp = 1; tmp != 0; pos += sizeof(abi_ulong))

        tmp = ldl(pos);

    _regs->gpr[5] = pos;

}

#define USE_ELF_CORE_DUMP

#define ELF_EXEC_PAGESIZE        4096

#endif

#ifdef TARGET_MIPS

#define ELF_START_MMAP 0x80000000

#define elf_check_arch(x) ( (x) == EM_MIPS )

#ifdef TARGET_MIPS64

#define ELF_CLASS   ELFCLASS64

#else

#define ELF_CLASS   ELFCLASS32

#endif

#ifdef TARGET_WORDS_BIGENDIAN

#define ELF_DATA        ELFDATA2MSB

#else

#define ELF_DATA        ELFDATA2LSB

#endif

#define ELF_ARCH    EM_MIPS

static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)

{

    regs->cp0_status = 2 << CP0St_KSU;

    regs->cp0_epc = infop->entry;

    regs->regs[29] = infop->start_stack;

}

#define USE_ELF_CORE_DUMP

#define ELF_EXEC_PAGESIZE        4096

#endif /* TARGET_MIPS */

#ifdef TARGET_SH4

#define ELF_START_MMAP 0x80000000

#define elf_check_arch(x) ( (x) == EM_SH )

#define ELF_CLASS ELFCLASS32

#define ELF_DATA  ELFDATA2LSB

#define ELF_ARCH  EM_SH

static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)

{

  /* Check other registers XXXXX */

  regs->pc = infop->entry;

  regs->regs[15] = infop->start_stack;

}

#define USE_ELF_CORE_DUMP

#define ELF_EXEC_PAGESIZE        4096

#endif

#ifdef TARGET_CRIS

#define ELF_START_MMAP 0x80000000

#define elf_check_arch(x) ( (x) == EM_CRIS )

#define ELF_CLASS ELFCLASS32

#define ELF_DATA  ELFDATA2LSB

#define ELF_ARCH  EM_CRIS

static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)

{

  regs->erp = infop->entry;

}

#define USE_ELF_CORE_DUMP

#define ELF_EXEC_PAGESIZE        8192

#endif

#ifdef TARGET_M68K

#define ELF_START_MMAP 0x80000000

#define elf_check_arch(x) ( (x) == EM_68K )

#define ELF_CLASS        ELFCLASS32

#define ELF_DATA        ELFDATA2MSB

#define ELF_ARCH        EM_68K

/* ??? Does this need to do anything?

#define ELF_PLAT_INIT(_r) */

static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)

{

    regs->usp = infop->start_stack;

    regs->sr = 0;

    regs->pc = infop->entry;

}

#define USE_ELF_CORE_DUMP

#define ELF_EXEC_PAGESIZE        8192

#endif

#ifdef TARGET_ALPHA

#define ELF_START_MMAP (0x30000000000ULL)

#define elf_check_arch(x) ( (x) == ELF_ARCH )

#define ELF_CLASS      ELFCLASS64

#define ELF_DATA       ELFDATA2MSB

#define ELF_ARCH       EM_ALPHA

static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)

{

    regs->pc = infop->entry;

    regs->ps = 8;

    regs->usp = infop->start_stack;

    regs->unique = infop->start_data; /* ? */

    printf("Set unique value to " TARGET_FMT_lx " (" TARGET_FMT_lx ")\n",

           regs->unique, infop->start_data);

}

#define USE_ELF_CORE_DUMP

#define ELF_EXEC_PAGESIZE        8192

#endif /* TARGET_ALPHA */

#ifndef ELF_PLATFORM

#define ELF_PLATFORM (NULL)

#endif

#ifndef ELF_HWCAP

#define ELF_HWCAP 0

#endif

#ifdef TARGET_ABI32

#undef ELF_CLASS

#define ELF_CLASS ELFCLASS32

#undef bswaptls

#define bswaptls(ptr) bswap32s(ptr)

#endif

#include "elf.h"

struct exec

{

  unsigned int a_info;   /* Use macros N_MAGIC, etc for access */

  unsigned int a_text;   /* length of text, in bytes */

  unsigned int a_data;   /* length of data, in bytes */

  unsigned int a_bss;    /* length of uninitialized data area, in bytes */

  unsigned int a_syms;   /* length of symbol table data in file, in bytes */

  unsigned int a_entry;  /* start address */

  unsigned int a_trsize; /* length of relocation info for text, in bytes */

  unsigned int a_drsize; /* length of relocation info for data, in bytes */

};

#define N_MAGIC(exec) ((exec).a_info & 0xffff)

#define OMAGIC 0407

#define NMAGIC 0410

#define ZMAGIC 0413

#define QMAGIC 0314

/* max code+data+bss space allocated to elf interpreter */

#define INTERP_MAP_SIZE (32 * 1024 * 1024)

/* max code+data+bss+brk space allocated to ET_DYN executables */

#define ET_DYN_MAP_SIZE (128 * 1024 * 1024)

/* Necessary parameters */

#define TARGET_ELF_EXEC_PAGESIZE TARGET_PAGE_SIZE

#define TARGET_ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(TARGET_ELF_EXEC_PAGESIZE-1))

#define TARGET_ELF_PAGEOFFSET(_v) ((_v) & (TARGET_ELF_EXEC_PAGESIZE-1))

#define INTERPRETER_NONE 0

#define INTERPRETER_AOUT 1

#define INTERPRETER_ELF 2

#define DLINFO_ITEMS 12

static inline void memcpy_fromfs(void * to, const void * from, unsigned long n)

{

        memcpy(to, from, n);

}

extern unsigned long x86_stack_size;

static int load_aout_interp(void * exptr, int interp_fd);

#ifdef BSWAP_NEEDED

static void bswap_ehdr(struct elfhdr *ehdr)

{

    bswap16s(&ehdr->e_type);                        /* Object file type */

    bswap16s(&ehdr->e_machine);                /* Architecture */

    bswap32s(&ehdr->e_version);                /* Object file version */

    bswaptls(&ehdr->e_entry);                /* Entry point virtual address */

    bswaptls(&ehdr->e_phoff);                /* Program header table file offset */

    bswaptls(&ehdr->e_shoff);                /* Section header table file offset */

    bswap32s(&ehdr->e_flags);                /* Processor-specific flags */

    bswap16s(&ehdr->e_ehsize);                /* ELF header size in bytes */

    bswap16s(&ehdr->e_phentsize);                /* Program header table entry size */

    bswap16s(&ehdr->e_phnum);                /* Program header table entry count */

    bswap16s(&ehdr->e_shentsize);                /* Section header table entry size */

    bswap16s(&ehdr->e_shnum);                /* Section header table entry count */

    bswap16s(&ehdr->e_shstrndx);                /* Section header string table index */

}

static void bswap_phdr(struct elf_phdr *phdr)

{

    bswap32s(&phdr->p_type);                        /* Segment type */

    bswaptls(&phdr->p_offset);                /* Segment file offset */

    bswaptls(&phdr->p_vaddr);                /* Segment virtual address */

    bswaptls(&phdr->p_paddr);                /* Segment physical address */

    bswaptls(&phdr->p_filesz);                /* Segment size in file */

    bswaptls(&phdr->p_memsz);                /* Segment size in memory */

    bswap32s(&phdr->p_flags);                /* Segment flags */

    bswaptls(&phdr->p_align);                /* Segment alignment */

}

static void bswap_shdr(struct elf_shdr *shdr)

{

    bswap32s(&shdr->sh_name);

    bswap32s(&shdr->sh_type);

    bswaptls(&shdr->sh_flags);

    bswaptls(&shdr->sh_addr);

    bswaptls(&shdr->sh_offset);

    bswaptls(&shdr->sh_size);

    bswap32s(&shdr->sh_link);

    bswap32s(&shdr->sh_info);

    bswaptls(&shdr->sh_addralign);

    bswaptls(&shdr->sh_entsize);

}

static void bswap_sym(struct elf_sym *sym)

{

    bswap32s(&sym->st_name);

    bswaptls(&sym->st_value);

    bswaptls(&sym->st_size);

    bswap16s(&sym->st_shndx);

}

#endif

/*

 * 'copy_elf_strings()' copies argument/envelope strings from user

 * memory to free pages in kernel mem. These are in a format ready

 * to be put directly into the top of new user memory.

 *

 */

static abi_ulong copy_elf_strings(int argc,char ** argv, void **page,

                                  abi_ulong p)

{

    char *tmp, *tmp1, *pag = NULL;

    int len, offset = 0;

    if (!p) {

        return 0;       /* bullet-proofing */

    }

    while (argc-- > 0) {

        tmp = argv[argc];

        if (!tmp) {

            fprintf(stderr, "VFS: argc is wrong");

            exit(-1);

        }

        tmp1 = tmp;

        while (*tmp++);

        len = tmp - tmp1;

        if (p < len) {  /* this shouldn't happen - 128kB */

                return 0;

        }

        while (len) {

            --p; --tmp; --len;

            if (--offset < 0) {

                offset = p % TARGET_PAGE_SIZE;

                pag = (char *)page[p/TARGET_PAGE_SIZE];

                if (!pag) {

                    pag = (char *)malloc(TARGET_PAGE_SIZE);

                    memset(pag, 0, TARGET_PAGE_SIZE);

                    page[p/TARGET_PAGE_SIZE] = pag;

                    if (!pag)

                        return 0;

                }

            }

            if (len == 0 || offset == 0) {

                *(pag + offset) = *tmp;

            }

            else {

              int bytes_to_copy = (len > offset) ? offset : len;

              tmp -= bytes_to_copy;

              p -= bytes_to_copy;

              offset -= bytes_to_copy;

              len -= bytes_to_copy;

              memcpy_fromfs(pag + offset, tmp, bytes_to_copy + 1);

            }

        }

    }

    return p;

}

static abi_ulong setup_arg_pages(abi_ulong p, struct linux_binprm *bprm,

                                 struct image_info *info)

{

    abi_ulong stack_base, size, error;

    int i;

    /* Create enough stack to hold everything.  If we don't use

     * it for args, we'll use it for something else...

     */

    size = x86_stack_size;

    if (size < MAX_ARG_PAGES*TARGET_PAGE_SIZE)

        size = MAX_ARG_PAGES*TARGET_PAGE_SIZE;

    error = target_mmap(0,

                        size + qemu_host_page_size,

                        PROT_READ | PROT_WRITE,

                        MAP_PRIVATE | MAP_ANONYMOUS,

                        -1, 0);

    if (error == -1) {

        perror("stk mmap");

        exit(-1);

    }

    /* we reserve one extra page at the top of the stack as guard */

    target_mprotect(error + size, qemu_host_page_size, PROT_NONE);

    stack_base = error + size - MAX_ARG_PAGES*TARGET_PAGE_SIZE;

    p += stack_base;

    for (i = 0 ; i < MAX_ARG_PAGES ; i++) {

        if (bprm->page[i]) {

            info->rss++;

            /* FIXME - check return value of memcpy_to_target() for failure */

            memcpy_to_target(stack_base, bprm->page[i], TARGET_PAGE_SIZE);

            free(bprm->page[i]);

        }

        stack_base += TARGET_PAGE_SIZE;

    }

    return p;

}

static void set_brk(abi_ulong start, abi_ulong end)

{

        /* page-align the start and end addresses... */

        start = HOST_PAGE_ALIGN(start);

        end = HOST_PAGE_ALIGN(end);

        if (end <= start)

                return;

        if(target_mmap(start, end - start,

                       PROT_READ | PROT_WRITE | PROT_EXEC,

                       MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0) == -1) {

            perror("cannot mmap brk");

            exit(-1);

        }

}

/* We need to explicitly zero any fractional pages after the data

   section (i.e. bss).  This would contain the junk from the file that

   should not be in memory. */

static void padzero(abi_ulong elf_bss, abi_ulong last_bss)

{

        abi_ulong nbyte;

        if (elf_bss >= last_bss)

                return;

        /* XXX: this is really a hack : if the real host page size is

           smaller than the target page size, some pages after the end

           of the file may not be mapped. A better fix would be to

           patch target_mmap(), but it is more complicated as the file

           size must be known */

        if (qemu_real_host_page_size < qemu_host_page_size) {

            abi_ulong end_addr, end_addr1;

            end_addr1 = (elf_bss + qemu_real_host_page_size - 1) &

                ~(qemu_real_host_page_size - 1);

            end_addr = HOST_PAGE_ALIGN(elf_bss);

            if (end_addr1 < end_addr) {

                mmap((void *)g2h(end_addr1), end_addr - end_addr1,

                     PROT_READ|PROT_WRITE|PROT_EXEC,

                     MAP_FIXED|MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);

            }

        }

        nbyte = elf_bss & (qemu_host_page_size-1);

        if (nbyte) {

            nbyte = qemu_host_page_size - nbyte;

            do {

                /* FIXME - what to do if put_user() fails? */

                put_user_u8(0, elf_bss);

                elf_bss++;

            } while (--nbyte);

        }

}

static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,

                                   struct elfhdr * exec,

                                   abi_ulong load_addr,

                                   abi_ulong load_bias,

                                   abi_ulong interp_load_addr, int ibcs,

                                   struct image_info *info)

{

        abi_ulong sp;

        int size;

        abi_ulong u_platform;

        const char *k_platform;

        const int n = sizeof(elf_addr_t);

        sp = p;

        u_platform = 0;

        k_platform = ELF_PLATFORM;

        if (k_platform) {

            size_t len = strlen(k_platform) + 1;

            sp -= (len + n - 1) & ~(n - 1);

            u_platform = sp;

            /* FIXME - check return value of memcpy_to_target() for failure */

            memcpy_to_target(sp, k_platform, len);

        }

        /*

         * Force 16 byte _final_ alignment here for generality.

         */

        sp = sp &~ (abi_ulong)15;

        size = (DLINFO_ITEMS + 1) * 2;

        if (k_platform)

          size += 2;

#ifdef DLINFO_ARCH_ITEMS

        size += DLINFO_ARCH_ITEMS * 2;

#endif

        size += envc + argc + 2;

        size += (!ibcs ? 3 : 1);        /* argc itself */

        size *= n;

        if (size & 15)

            sp -= 16 - (size & 15);

        /* This is correct because Linux defines

         * elf_addr_t as Elf32_Off / Elf64_Off

         */

#define NEW_AUX_ENT(id, val) do {                \

            sp -= n; put_user_ual(val, sp);        \

            sp -= n; put_user_ual(id, sp);        \

          } while(0)

        NEW_AUX_ENT (AT_NULL, 0);

        /* There must be exactly DLINFO_ITEMS entries here.  */

        NEW_AUX_ENT(AT_PHDR, (abi_ulong)(load_addr + exec->e_phoff));

        NEW_AUX_ENT(AT_PHENT, (abi_ulong)(sizeof (struct elf_phdr)));

        NEW_AUX_ENT(AT_PHNUM, (abi_ulong)(exec->e_phnum));

        NEW_AUX_ENT(AT_PAGESZ, (abi_ulong)(TARGET_PAGE_SIZE));

        NEW_AUX_ENT(AT_BASE, (abi_ulong)(interp_load_addr));

        NEW_AUX_ENT(AT_FLAGS, (abi_ulong)0);

        NEW_AUX_ENT(AT_ENTRY, load_bias + exec->e_entry);

        NEW_AUX_ENT(AT_UID, (abi_ulong) getuid());

        NEW_AUX_ENT(AT_EUID, (abi_ulong) geteuid());

        NEW_AUX_ENT(AT_GID, (abi_ulong) getgid());

        NEW_AUX_ENT(AT_EGID, (abi_ulong) getegid());

        NEW_AUX_ENT(AT_HWCAP, (abi_ulong) ELF_HWCAP);

        NEW_AUX_ENT(AT_CLKTCK, (abi_ulong) sysconf(_SC_CLK_TCK));

        if (k_platform)

            NEW_AUX_ENT(AT_PLATFORM, u_platform);

#ifdef ARCH_DLINFO

        /*

         * ARCH_DLINFO must come last so platform specific code can enforce

         * special alignment requirements on the AUXV if necessary (eg. PPC).

         */

        ARCH_DLINFO;

#endif

#undef NEW_AUX_ENT

        sp = loader_build_argptr(envc, argc, sp, p, !ibcs);

        return sp;

}

static abi_ulong load_elf_interp(struct elfhdr * interp_elf_ex,

                                 int interpreter_fd,

                                 abi_ulong *interp_load_addr)

{

        struct elf_phdr *elf_phdata  =  NULL;

        struct elf_phdr *eppnt;

        abi_ulong load_addr = 0;

        int load_addr_set = 0;

        int retval;

        abi_ulong last_bss, elf_bss;

        abi_ulong error;

        int i;

        elf_bss = 0;

        last_bss = 0;

        error = 0;

#ifdef BSWAP_NEEDED

        bswap_ehdr(interp_elf_ex);

#endif

        /* First of all, some simple consistency checks */

        if ((interp_elf_ex->e_type != ET_EXEC &&

             interp_elf_ex->e_type != ET_DYN) ||

           !elf_check_arch(interp_elf_ex->e_machine)) {

                return ~((abi_ulong)0UL);

        }

        /* Now read in all of the header information */

        if (sizeof(struct elf_phdr) * interp_elf_ex->e_phnum > TARGET_PAGE_SIZE)

            return ~(abi_ulong)0UL;

        elf_phdata =  (struct elf_phdr *)

                malloc(sizeof(struct elf_phdr) * interp_elf_ex->e_phnum);

        if (!elf_phdata)

          return ~((abi_ulong)0UL);

        /*

         * If the size of this structure has changed, then punt, since

         * we will be doing the wrong thing.

         */

        if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr)) {

            free(elf_phdata);

            return ~((abi_ulong)0UL);

        }

        retval = lseek(interpreter_fd, interp_elf_ex->e_phoff, SEEK_SET);

        if(retval >= 0) {

            retval = read(interpreter_fd,

                           (char *) elf_phdata,

                           sizeof(struct elf_phdr) * interp_elf_ex->e_phnum);

        }

        if (retval < 0) {

                perror("load_elf_interp");