kpatch/kmod/core/kpatch.h
Josh Poimboeuf bfad3b1880 kmod/core: update API and use hash table
My apologies for the size of this commit.  I combined these two features
(updating API and using a hash table) into a single commit because their
implementations are tightly coupled and I didn't want to have to add
support for the old kpatch_funcs array with the new API just for the
sake of splitting up the commit :-)

- Update the core module API to get a more clear separation between core
  module and patch module.  This is cleaner and will help our case for
  getting the core module merged upstream into the kernel.
- Convert the old kpatch_funcs array into a hash table.  This is so much
  nicer performance-wise and everything-else-wise than that ugly old
  array.
- Do the incremental patching in stop machine.  This ensures that the
  funcs hash is up to date and we don't miss anything.
- Disable preemption in the ftrace handler when accessing the func hash.
  That way we don't get conflicts with the stop_machine handler updating
  the hash.
2014-03-18 13:34:15 -05:00

44 lines
1.3 KiB
C

/*
* kpatch.h
*
* Copyright (C) 2014 Seth Jennings <sjenning@redhat.com>
* Copyright (C) 2013-2014 Josh Poimboeuf <jpoimboe@redhat.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA,
* 02110-1301, USA.
*
* Contains the API for the core kpatch module used by the patch modules
*/
#ifndef _KPATCH_H_
#define _KPATCH_H_
#include <linux/types.h>
struct kpatch_func {
unsigned long new_addr;
unsigned long old_addr;
unsigned long old_size;
struct module *mod;
struct hlist_node node;
};
extern int kpatch_register(struct module *mod, struct kpatch_func *funcs,
int num_funcs);
extern int kpatch_unregister(struct module *mod, struct kpatch_func *funcs,
int num_funcs);
#endif /* _KPATCH_H_ */