arch/x86/mm/debug_pagetables.c

   1 #include <linux/debugfs.h>
   2 #include <linux/module.h>
   3 #include <linux/seq_file.h>
   4 #include <asm/pgtable.h>
   5
   6 static int ptdump_show(struct seq_file *m, void *v)
   7 {
   8         ptdump_walk_pgd_level(m, NULL);
   9         return 0;
  10 }
  11
  12 static int ptdump_open(struct inode *inode, struct file *filp)
  13 {
  14         return single_open(filp, ptdump_show, NULL);
  15 }
  16
  17 static const struct file_operations ptdump_fops = {
  18         .owner          = THIS_MODULE,
  19         .open           = ptdump_open,
  20         .read           = seq_read,
  21         .llseek         = seq_lseek,
  22         .release        = single_release,
  23 };
  24
  25 static struct dentry *pe;
  26
  27 static int __init pt_dump_debug_init(void)
  28 {
  29         pe = debugfs_create_file("kernel_page_tables", S_IRUSR, NULL, NULL,
  30                                  &ptdump_fops);
  31         if (!pe)
  32                 return -ENOMEM;
  33
  34         return 0;
  35 }
  36
  37 static void __exit pt_dump_debug_exit(void)
  38 {
  39         debugfs_remove_recursive(pe);
  40 }
  41
  42 module_init(pt_dump_debug_init);
  43 module_exit(pt_dump_debug_exit);
  44 MODULE_LICENSE("GPL");
  45 MODULE_AUTHOR("Arjan van de Ven <arjan@linux.intel.com>");
  46 MODULE_DESCRIPTION("Kernel debugging helper that dumps pagetables");