// SPDX-License-Identifier: GPL-2.0/* * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) */ #include <linux/init.h>#include <linux/memblock.h>#include <linux/initrd.h>#include <asm/types.h>#include <init.h>#include <os.h> /* Changed by uml_initrd_setup, which is a setup */static char *initrd __initdata = NULL;static int load_initrd(char *filename, void *buf, int size); int __init read_initrd(void){	void *area;	long long size;	int err; 	if (initrd == NULL)		return 0; 	err = os_file_size(initrd, &size);	if (err)		return 0; 	/*	 * This is necessary because alloc_bootmem craps out if you	 * ask for no memory.	 */	if (size == 0) {		printk(KERN_ERR "\"%s\" is a zero-size initrd\n", initrd);		return 0;	} 	area = memblock_alloc(size, SMP_CACHE_BYTES);	if (!area)		panic("%s: Failed to allocate %llu bytes\n", __func__, size); 	if (load_initrd(initrd, area, size) == -1)		return 0; 	initrd_start = (unsigned long) area;	initrd_end = initrd_start + size;	return 0;} static int __init uml_initrd_setup(char *line, int *add){	initrd = line;	return 0;} __uml_setup("initrd=", uml_initrd_setup,"initrd=<initrd image>\n""    This is used to boot UML from an initrd image.  The argument is the\n""    name of the file containing the image.\n\n"); static int load_initrd(char *filename, void *buf, int size){	int fd, n; 	fd = os_open_file(filename, of_read(OPENFLAGS()), 0);	if (fd < 0) {		printk(KERN_ERR "Opening '%s' failed - err = %d\n", filename,		       -fd);		return -1;	}	n = os_read_file(fd, buf, size);	if (n != size) {		printk(KERN_ERR "Read of %d bytes from '%s' failed, "		       "err = %d\n", size,		       filename, -n);		return -1;	} 	os_close_file(fd);	return 0;}