Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2)  * debugfs ops for process ASIDs
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *  Copyright (C) 2000, 2001  Paolo Alberelli
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  *  Copyright (C) 2003 - 2008  Paul Mundt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  *  Copyright (C) 2003, 2004  Richard Curnow
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8)  * Provides a debugfs file that lists out the ASIDs currently associated
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9)  * with the processes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11)  * In the SH-5 case, if the DM.PC register is examined through the debug
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12)  * link, this shows ASID + PC. To make use of this, the PID->ASID
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)  * relationship needs to be known. This is primarily for debugging.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)  * This file is subject to the terms and conditions of the GNU General Public
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16)  * License.  See the file "COPYING" in the main directory of this archive
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)  * for more details.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include <linux/debugfs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #include <linux/seq_file.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) #include <linux/spinlock.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #include <linux/sched/signal.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) #include <linux/sched/task.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) #include <asm/processor.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) #include <asm/mmu_context.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) static int asids_seq_show(struct seq_file *file, void *iter)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 	struct task_struct *p;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 	read_lock(&tasklist_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 	for_each_process(p) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 		int pid = p->pid;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 		if (unlikely(!pid))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 			continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 		if (p->mm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 			seq_printf(file, "%5d : %04lx\n", pid,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 				   cpu_asid(smp_processor_id(), p->mm));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 	read_unlock(&tasklist_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) static int asids_debugfs_open(struct inode *inode, struct file *file)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 	return single_open(file, asids_seq_show, inode->i_private);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) static const struct file_operations asids_debugfs_fops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 	.owner		= THIS_MODULE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 	.open		= asids_debugfs_open,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 	.read		= seq_read,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 	.llseek		= seq_lseek,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 	.release	= single_release,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) static int __init asids_debugfs_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 	debugfs_create_file("asids", S_IRUSR, arch_debugfs_dir, NULL,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 			    &asids_debugfs_fops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) device_initcall(asids_debugfs_init);