[patch V181 51/54] x86/mm/dump_pagetables: Add page table directory

[Thomas Gleixner]

The upcoming support for dumping the kernel and the user space page tables
of the current process would create more random files in the top level
debugfs directory.

Add a page table directory and move the existing file to it.

Signed-off-by: Borislav Petkov <b...@suse.de>
Signed-off-by: Ingo Molnar <mi...@kernel.org>
Signed-off-by: Thomas Gleixner <t...@linutronix.de>
Cc: Andy Lutomirski <l...@kernel.org>
Cc: Boris Ostrovsky <boris.ostrov...@oracle.com>
Cc: Borislav Petkov <b...@alien8.de>
Cc: Brian Gerst <brge...@gmail.com>
Cc: Dave Hansen <dave.han...@linux.intel.com>
Cc: David Laight <david.lai...@aculab.com>
Cc: Denys Vlasenko <dvlas...@redhat.com>
Cc: Eduardo Valentin <edu...@amazon.com>
Cc: Greg KH <gre...@linuxfoundation.org>
Cc: H. Peter Anvin <h...@zytor.com>
Cc: Josh Poimboeuf <jpoim...@redhat.com>
Cc: Juergen Gross <jgr...@suse.com>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Will Deacon <will.dea...@arm.com>
Cc: aligu...@amazon.com
Cc: daniel.gr...@iaik.tugraz.at
Cc: hu...@google.com
Cc: keesc...@google.com
---
 arch/x86/mm/debug_pagetables.c |   15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

--- a/arch/x86/mm/debug_pagetables.c
+++ b/arch/x86/mm/debug_pagetables.c
@@ -22,21 +22,26 @@ static const struct file_operations ptdu
        .release        = single_release,
 };
 
-static struct dentry *pe;
+static struct dentry *dir, *pe;
 
 static int __init pt_dump_debug_init(void)
 {
-       pe = debugfs_create_file("kernel_page_tables", S_IRUSR, NULL, NULL,
-                                &ptdump_fops);
-       if (!pe)
+       dir = debugfs_create_dir("page_tables", NULL);
+       if (!dir)
                return -ENOMEM;
 
+       pe = debugfs_create_file("kernel", 0400, dir, NULL, &ptdump_fops);
+       if (!pe)
+               goto err;
        return 0;
+err:
+       debugfs_remove_recursive(dir);
+       return -ENOMEM;
 }
 
 static void __exit pt_dump_debug_exit(void)
 {
-       debugfs_remove_recursive(pe);
+       debugfs_remove_recursive(dir);
 }
 
 module_init(pt_dump_debug_init);