Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6) #include <linux/ctype.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/proc_fs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/seq_file.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/uaccess.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16)  * If read and write race, the read will still atomically read a valid
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)  * value.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) int uml_exitcode = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) static int exitcode_proc_show(struct seq_file *m, void *v)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 	int val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 	 * Save uml_exitcode in a local so that we don't need to guarantee
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 	 * that sprintf accesses it atomically.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 	val = uml_exitcode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 	seq_printf(m, "%d\n", val);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) static int exitcode_proc_open(struct inode *inode, struct file *file)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 	return single_open(file, exitcode_proc_show, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) static ssize_t exitcode_proc_write(struct file *file,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 		const char __user *buffer, size_t count, loff_t *pos)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 	char *end, buf[sizeof("nnnnn\0")];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 	size_t size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 	int tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 	size = min(count, sizeof(buf));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 	if (copy_from_user(buf, buffer, size))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 		return -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 	tmp = simple_strtol(buf, &end, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 	if ((*end != '\0') && !isspace(*end))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) 	uml_exitcode = tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 	return count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) static const struct proc_ops exitcode_proc_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 	.proc_open	= exitcode_proc_open,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 	.proc_read	= seq_read,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 	.proc_lseek	= seq_lseek,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 	.proc_release	= single_release,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 	.proc_write	= exitcode_proc_write,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) static int make_proc_exitcode(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 	struct proc_dir_entry *ent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 	ent = proc_create("exitcode", 0600, NULL, &exitcode_proc_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 	if (ent == NULL) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) 		printk(KERN_WARNING "make_proc_exitcode : Failed to register "
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 		       "/proc/exitcode\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) __initcall(make_proc_exitcode);