Fixed MTP to work with TWRP

arch/tile/mm/elf.c

@@ -0,0 +1,154 @@
+/*
+ * 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/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)
+{
+	char *buf, *path;
+	struct vm_area_struct *vma;
+
+	if (!sim_is_simulator())
+		return 1;
+
+	if (mm->exe_file == NULL)
+		return 0;
+
+	for (vma = current->mm->mmap; ; vma = vma->vm_next) {
+		if (vma == NULL)
+			return 0;
+		if (vma->vm_file == mm->exe_file)
+			break;
+	}
+
+	buf = (char *) __get_free_page(GFP_KERNEL);
+	if (buf == NULL)
+		return 0;
+
+	path = d_path(&mm->exe_file->f_path, buf, PAGE_SIZE);
+	if (IS_ERR(path)) {
+		free_page((unsigned long)buf);
+		return 0;
+	}
+
+	/*
+	 * 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')
+				break;
+		}
+	}
+
+	sim_notify_exec(path);
+	free_page((unsigned long)buf);
+	return 1;
+}
+
+/* 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;
+
+	down_write(&mm->mmap_sem);
+
+	/*
+	 * 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);
+
+	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);
+}