2 * debugfs ops for process ASIDs
4 * Copyright (C) 2000, 2001 Paolo Alberelli
5 * Copyright (C) 2003 - 2008 Paul Mundt
6 * Copyright (C) 2003, 2004 Richard Curnow
8 * Provides a debugfs file that lists out the ASIDs currently associated
11 * In the SH-5 case, if the DM.PC register is examined through the debug
12 * link, this shows ASID + PC. To make use of this, the PID->ASID
13 * relationship needs to be known. This is primarily for debugging.
15 * This file is subject to the terms and conditions of the GNU General Public
16 * License. See the file "COPYING" in the main directory of this archive
19 #include <linux/init.h>
20 #include <linux/debugfs.h>
21 #include <linux/seq_file.h>
22 #include <linux/spinlock.h>
23 #include <linux/sched/signal.h>
25 #include <asm/processor.h>
26 #include <asm/mmu_context.h>
28 static int asids_seq_show(struct seq_file *file, void *iter)
30 struct task_struct *p;
32 read_lock(&tasklist_lock);
41 seq_printf(file, "%5d : %04lx\n", pid,
42 cpu_asid(smp_processor_id(), p->mm));
45 read_unlock(&tasklist_lock);
50 static int asids_debugfs_open(struct inode *inode, struct file *file)
52 return single_open(file, asids_seq_show, inode->i_private);
55 static const struct file_operations asids_debugfs_fops = {
57 .open = asids_debugfs_open,
60 .release = single_release,
63 static int __init asids_debugfs_init(void)
65 struct dentry *asids_dentry;
67 asids_dentry = debugfs_create_file("asids", S_IRUSR, arch_debugfs_dir,
68 NULL, &asids_debugfs_fops);
72 return PTR_ERR_OR_ZERO(asids_dentry);
74 device_initcall(asids_debugfs_init);