Make all seq_operations structs const, to help mitigate against
revectoring user-triggerable function pointers.

This is derived from the grsecurity patch, although generated from scratch
because it's simpler than extracting the changes from there.

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge reason: we were on -rc4, move to -rc8 before applying
              a new batch of locking infrastructure changes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

Since lockdep has introduced BFS to avoid recursion, statistics
for recursion does not make any sense now. So remove them.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Cc: a.p.zijlstra@chello.nl
LKML-Reference: <1251542879-5211-1-git-send-email-tom.leiming@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

- make ls_next() call ls_start()
- remove redundant code in lock_stat_release()

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4A88ED6B.6030602@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

- make lc_next() call lc_start()
- use lock_chains directly instead of storing it in m->private

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4A88ED57.5060609@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Use seq_list_start_head() and seq_list_next().

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4A88ED41.5000000@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Two entries are missing in the output of /proc/lock_chains.

One is chains[1]. When lc_next() is called the 1st time,
chains[0] is returned. And when it's called the 2nd time,
chains[2] is returned.

The other missing ons is, when lc_start() is called the 2nd
time, we should start from chains[@pos-1] but not chains[@pos],
because pos == 0 is the header.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4A88ED25.2040306@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

One entry is missing in the output of /proc/lock_stat.

The cause is, when ls_start() is called the 2nd time, we should
start from stats[@pos-1] but not stats[@pos], because pos == 0
is the header.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4A88ED15.20800@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

/proc/lock_stat is writable.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4A7BE7B6.10904@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Fix:

  kernel/built-in.o: In function `lockdep_stats_show':
  lockdep_proc.c:(.text+0x48202): undefined reference to `max_bfs_queue_depth'

As max_bfs_queue_depth is only available under
CONFIG_PROVE_LOCKING=y.

Cc: Ming Lei <tom.leiming@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>