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-rw-r--r--arch/tile/mm/elf.c165
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);
+}