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/*

 * IA-32 ELF support.

 *

 * Copyright (C) 1999 Arun Sharma <arun.sharma@intel.com>

 * Copyright (C) 2001 Hewlett-Packard Co

 *      David Mosberger-Tang <davidm@hpl.hp.com>

 *

 * 06/16/00     A. Mallick      initialize csd/ssd/tssd/cflg for ia32_load_state

 * 04/13/01     D. Mosberger    dropped saving tssd in ar.k1---it's not needed

 * 09/14/01     D. Mosberger    fixed memory management for gdt/tss page

 */

#include <linux/config.h>

#include <linux/types.h>

#include <asm/param.h>

#include <asm/signal.h>

#include <asm/ia32.h>

#define CONFIG_BINFMT_ELF32

/* Override some function names */

#undef start_thread

#define start_thread                    ia32_start_thread

#define elf_format                      elf32_format

#define init_elf_binfmt                 init_elf32_binfmt

#define exit_elf_binfmt                 exit_elf32_binfmt

#undef CONFIG_BINFMT_ELF

#ifdef CONFIG_BINFMT_ELF32

# define CONFIG_BINFMT_ELF              CONFIG_BINFMT_ELF32

#endif

#undef CONFIG_BINFMT_ELF_MODULE

#ifdef CONFIG_BINFMT_ELF32_MODULE

# define CONFIG_BINFMT_ELF_MODULE       CONFIG_BINFMT_ELF32_MODULE

#endif

#undef CLOCKS_PER_SEC

#define CLOCKS_PER_SEC  IA32_CLOCKS_PER_SEC

extern void ia64_elf32_init (struct pt_regs *regs);

extern void put_dirty_page (struct task_struct * tsk, struct page *page, unsigned long address);

static void elf32_set_personality (void);

#define ELF_PLAT_INIT(_r, load_addr)    ia64_elf32_init(_r)

#define setup_arg_pages(bprm)           ia32_setup_arg_pages(bprm)

#define elf_map                         elf32_map

#undef SET_PERSONALITY

#define SET_PERSONALITY(ex, ibcs2)      elf32_set_personality()

/* Ugly but avoids duplication */

#include "../../../fs/binfmt_elf.c"

extern struct page *ia32_shared_page[];

extern unsigned long *ia32_gdt;

struct page *

ia32_install_shared_page (struct vm_area_struct *vma, unsigned long address, int no_share)

{

        struct page *pg = ia32_shared_page[(address - vma->vm_start)/PAGE_SIZE];

        get_page(pg);

        return pg;

}

static struct vm_operations_struct ia32_shared_page_vm_ops = {

        .nopage =ia32_install_shared_page

};

void

ia64_elf32_init (struct pt_regs *regs)

{

        struct vm_area_struct *vma;

        /*

         * Map GDT and TSS below 4GB, where the processor can find them.  We need to map

         * it with privilege level 3 because the IVE uses non-privileged accesses to these

         * tables.  IA-32 segmentation is used to protect against IA-32 accesses to them.

         */

        vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);

        if (vma) {

                vma->vm_mm = current->mm;

                vma->vm_start = IA32_GDT_OFFSET;

                vma->vm_end = vma->vm_start + max(PAGE_SIZE, 2*IA32_PAGE_SIZE);

                vma->vm_page_prot = PAGE_SHARED;

                vma->vm_flags = VM_READ|VM_MAYREAD;

                vma->vm_ops = &ia32_shared_page_vm_ops;

                vma->vm_pgoff = 0;

                vma->vm_file = NULL;

                vma->vm_private_data = NULL;

                down_write(&current->mm->mmap_sem);

                {

                        insert_vm_struct(current->mm, vma);

                }

                up_write(&current->mm->mmap_sem);

        }

        /*

         * Install LDT as anonymous memory.  This gives us all-zero segment descriptors

         * until a task modifies them via modify_ldt().

         */

        vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);

        if (vma) {

                vma->vm_mm = current->mm;

                vma->vm_start = IA32_LDT_OFFSET;

                vma->vm_end = vma->vm_start + PAGE_ALIGN(IA32_LDT_ENTRIES*IA32_LDT_ENTRY_SIZE);

                vma->vm_page_prot = PAGE_SHARED;

                vma->vm_flags = VM_READ|VM_WRITE|VM_MAYREAD|VM_MAYWRITE;

                vma->vm_ops = NULL;

                vma->vm_pgoff = 0;

                vma->vm_file = NULL;

                vma->vm_private_data = NULL;

                down_write(&current->mm->mmap_sem);

                {

                        insert_vm_struct(current->mm, vma);

                }

                up_write(&current->mm->mmap_sem);

        }

        ia64_psr(regs)->ac = 0;          /* turn off alignment checking */

        regs->loadrs = 0;

        /*

         *  According to the ABI %edx points to an `atexit' handler.  Since we don't have

         *  one we'll set it to 0 and initialize all the other registers just to make

         *  things more deterministic, ala the i386 implementation.

         */

        regs->r8 = 0;    /* %eax */

        regs->r11 = 0;   /* %ebx */

        regs->r9 = 0;    /* %ecx */

        regs->r10 = 0;   /* %edx */

        regs->r13 = 0;   /* %ebp */

        regs->r14 = 0;   /* %esi */

        regs->r15 = 0;   /* %edi */

        current->thread.eflag = IA32_EFLAG;

        current->thread.fsr = IA32_FSR_DEFAULT;

        current->thread.fcr = IA32_FCR_DEFAULT;

        current->thread.fir = 0;

        current->thread.fdr = 0;

        /*

         * Setup GDTD.  Note: GDTD is the descrambled version of the pseudo-descriptor

         * format defined by Figure 3-11 "Pseudo-Descriptor Format" in the IA-32

         * architecture manual. Also note that the only fields that are not ignored are

         * `base', `limit', 'G', `P' (must be 1) and `S' (must be 0).

         */

        regs->r31 = IA32_SEG_UNSCRAMBLE(IA32_SEG_DESCRIPTOR(IA32_GDT_OFFSET, IA32_PAGE_SIZE - 1,

                                                            0, 0, 0, 1, 0, 0, 0));

        /* Setup the segment selectors */

        regs->r16 = (__USER_DS << 16) | __USER_DS; /* ES == DS, GS, FS are zero */

        regs->r17 = (__USER_DS << 16) | __USER_CS; /* SS, CS; ia32_load_state() sets TSS and LDT */

        ia32_load_segment_descriptors(current);

        ia32_load_state(current);

}

int

ia32_setup_arg_pages (struct linux_binprm *bprm)

{

        unsigned long stack_base;

        struct vm_area_struct *mpnt;

        int i;

        stack_base = IA32_STACK_TOP - MAX_ARG_PAGES*PAGE_SIZE;

        bprm->p += stack_base;

        if (bprm->loader)

                bprm->loader += stack_base;

        bprm->exec += stack_base;

        mpnt = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);

        if (!mpnt)

                return -ENOMEM;

        down_write(&current->mm->mmap_sem);

        {

                mpnt->vm_mm = current->mm;

                mpnt->vm_start = PAGE_MASK & (unsigned long) bprm->p;

                mpnt->vm_end = IA32_STACK_TOP;

                mpnt->vm_page_prot = PAGE_COPY;

                mpnt->vm_flags = VM_STACK_FLAGS;

                mpnt->vm_ops = NULL;

                mpnt->vm_pgoff = 0;

                mpnt->vm_file = NULL;

                mpnt->vm_private_data = 0;

                insert_vm_struct(current->mm, mpnt);

                current->mm->total_vm = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT;

        }

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

                struct page *page = bprm->page[i];

                if (page) {

                        bprm->page[i] = NULL;

                        put_dirty_page(current, page, stack_base);

                }

                stack_base += PAGE_SIZE;

        }

        up_write(&current->mm->mmap_sem);

        return 0;

}

static void

elf32_set_personality (void)

{

        set_personality(PER_LINUX32);

        current->thread.map_base  = IA32_PAGE_OFFSET/3;

        current->thread.task_size = IA32_PAGE_OFFSET;   /* use what Linux/x86 uses... */

        current->thread.flags |= IA64_THREAD_XSTACK;    /* data must be executable */

        set_fs(USER_DS);                                /* set addr limit for new TASK_SIZE */

}

static unsigned long

elf32_map (struct file *filep, unsigned long addr, struct elf_phdr *eppnt, int prot, int type)

{

        unsigned long pgoff = (eppnt->p_vaddr) & ~IA32_PAGE_MASK;

        return ia32_do_mmap(filep, (addr & IA32_PAGE_MASK), eppnt->p_filesz + pgoff, prot, type,

                            eppnt->p_offset - pgoff);

}