diff options
Diffstat (limited to 'arch/tile/mm/elf.c')
| -rw-r--r-- | arch/tile/mm/elf.c | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/arch/tile/mm/elf.c b/arch/tile/mm/elf.c new file mode 100644 index 000000000..f7ddae372 --- /dev/null +++ b/arch/tile/mm/elf.c @@ -0,0 +1,165 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * 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, version 2. + * + * 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, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/mm.h> +#include <linux/pagemap.h> +#include <linux/binfmts.h> +#include <linux/compat.h> +#include <linux/mman.h> +#include <linux/file.h> +#include <linux/elf.h> +#include <asm/pgtable.h> +#include <asm/pgalloc.h> +#include <asm/sections.h> +#include <asm/vdso.h> +#include <arch/sim.h> + +/* Notify a running simulator, if any, that an exec just occurred. */ +static void sim_notify_exec(const char *binary_name) +{ + unsigned char c; + do { + c = *binary_name++; + __insn_mtspr(SPR_SIM_CONTROL, + (SIM_CONTROL_OS_EXEC + | (c << _SIM_CONTROL_OPERATOR_BITS))); + + } while (c); +} + +static int notify_exec(struct mm_struct *mm) +{ + int ret = 0; + char *buf, *path; + struct vm_area_struct *vma; + struct file *exe_file; + + if (!sim_is_simulator()) + return 1; + + buf = (char *) __get_free_page(GFP_KERNEL); + if (buf == NULL) + return 0; + + exe_file = get_mm_exe_file(mm); + if (exe_file == NULL) + goto done_free; + + path = d_path(&exe_file->f_path, buf, PAGE_SIZE); + if (IS_ERR(path)) + goto done_put; + + down_read(&mm->mmap_sem); + for (vma = current->mm->mmap; ; vma = vma->vm_next) { + if (vma == NULL) { + up_read(&mm->mmap_sem); + goto done_put; + } + if (vma->vm_file == exe_file) + break; + } + + /* + * Notify simulator of an ET_DYN object so we know the load address. + * The somewhat cryptic overuse of SIM_CONTROL_DLOPEN allows us + * to be backward-compatible with older simulator releases. + */ + if (vma->vm_start == (ELF_ET_DYN_BASE & PAGE_MASK)) { + char buf[64]; + int i; + + snprintf(buf, sizeof(buf), "0x%lx:@", vma->vm_start); + for (i = 0; ; ++i) { + char c = buf[i]; + __insn_mtspr(SPR_SIM_CONTROL, + (SIM_CONTROL_DLOPEN + | (c << _SIM_CONTROL_OPERATOR_BITS))); + if (c == '\0') { + ret = 1; /* success */ + break; + } + } + } + up_read(&mm->mmap_sem); + + sim_notify_exec(path); +done_put: + fput(exe_file); +done_free: + free_page((unsigned long)buf); + return ret; +} + +/* Notify a running simulator, if any, that we loaded an interpreter. */ +static void sim_notify_interp(unsigned long load_addr) +{ + size_t i; + for (i = 0; i < sizeof(load_addr); i++) { + unsigned char c = load_addr >> (i * 8); + __insn_mtspr(SPR_SIM_CONTROL, + (SIM_CONTROL_OS_INTERP + | (c << _SIM_CONTROL_OPERATOR_BITS))); + } +} + + +int arch_setup_additional_pages(struct linux_binprm *bprm, + int executable_stack) +{ + struct mm_struct *mm = current->mm; + int retval = 0; + + /* + * Notify the simulator that an exec just occurred. + * If we can't find the filename of the mapping, just use + * whatever was passed as the linux_binprm filename. + */ + if (!notify_exec(mm)) + sim_notify_exec(bprm->filename); + + down_write(&mm->mmap_sem); + + retval = setup_vdso_pages(); + +#ifndef __tilegx__ + /* + * Set up a user-interrupt mapping here; the user can't + * create one themselves since it is above TASK_SIZE. + * We make it unwritable by default, so the model for adding + * interrupt vectors always involves an mprotect. + */ + if (!retval) { + unsigned long addr = MEM_USER_INTRPT; + addr = mmap_region(NULL, addr, INTRPT_SIZE, + VM_READ|VM_EXEC| + VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, 0); + if (addr > (unsigned long) -PAGE_SIZE) + retval = (int) addr; + } +#endif + + up_write(&mm->mmap_sem); + + return retval; +} + + +void elf_plat_init(struct pt_regs *regs, unsigned long load_addr) +{ + /* Zero all registers. */ + memset(regs, 0, sizeof(*regs)); + + /* Report the interpreter's load address. */ + sim_notify_interp(load_addr); +} |