linux-hardened/include/linux/context_tracking.h
Andy Lutomirski f9281648ec context_tracking: Add ct_state() and CT_WARN_ON()
This will let us sprinkle sanity checks around the kernel
without making too much of a mess.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/5da41fb2ceb29eac671f427c67040401ba2a1fa0.1435952415.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07 10:59:04 +02:00

125 lines
3 KiB
C

#ifndef _LINUX_CONTEXT_TRACKING_H
#define _LINUX_CONTEXT_TRACKING_H
#include <linux/sched.h>
#include <linux/vtime.h>
#include <linux/context_tracking_state.h>
#include <asm/ptrace.h>
#ifdef CONFIG_CONTEXT_TRACKING
extern void context_tracking_cpu_set(int cpu);
extern void context_tracking_enter(enum ctx_state state);
extern void context_tracking_exit(enum ctx_state state);
extern void context_tracking_user_enter(void);
extern void context_tracking_user_exit(void);
static inline void user_enter(void)
{
if (context_tracking_is_enabled())
context_tracking_user_enter();
}
static inline void user_exit(void)
{
if (context_tracking_is_enabled())
context_tracking_user_exit();
}
static inline enum ctx_state exception_enter(void)
{
enum ctx_state prev_ctx;
if (!context_tracking_is_enabled())
return 0;
prev_ctx = this_cpu_read(context_tracking.state);
if (prev_ctx != CONTEXT_KERNEL)
context_tracking_exit(prev_ctx);
return prev_ctx;
}
static inline void exception_exit(enum ctx_state prev_ctx)
{
if (context_tracking_is_enabled()) {
if (prev_ctx != CONTEXT_KERNEL)
context_tracking_enter(prev_ctx);
}
}
/**
* ct_state() - return the current context tracking state if known
*
* Returns the current cpu's context tracking state if context tracking
* is enabled. If context tracking is disabled, returns
* CONTEXT_DISABLED. This should be used primarily for debugging.
*/
static inline enum ctx_state ct_state(void)
{
return context_tracking_is_enabled() ?
this_cpu_read(context_tracking.state) : CONTEXT_DISABLED;
}
#else
static inline void user_enter(void) { }
static inline void user_exit(void) { }
static inline enum ctx_state exception_enter(void) { return 0; }
static inline void exception_exit(enum ctx_state prev_ctx) { }
static inline enum ctx_state ct_state(void) { return CONTEXT_DISABLED; }
#endif /* !CONFIG_CONTEXT_TRACKING */
#define CT_WARN_ON(cond) WARN_ON(context_tracking_is_enabled() && (cond))
#ifdef CONFIG_CONTEXT_TRACKING_FORCE
extern void context_tracking_init(void);
#else
static inline void context_tracking_init(void) { }
#endif /* CONFIG_CONTEXT_TRACKING_FORCE */
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
static inline void guest_enter(void)
{
if (vtime_accounting_enabled())
vtime_guest_enter(current);
else
current->flags |= PF_VCPU;
if (context_tracking_is_enabled())
context_tracking_enter(CONTEXT_GUEST);
}
static inline void guest_exit(void)
{
if (context_tracking_is_enabled())
context_tracking_exit(CONTEXT_GUEST);
if (vtime_accounting_enabled())
vtime_guest_exit(current);
else
current->flags &= ~PF_VCPU;
}
#else
static inline void guest_enter(void)
{
/*
* This is running in ioctl context so its safe
* to assume that it's the stime pending cputime
* to flush.
*/
vtime_account_system(current);
current->flags |= PF_VCPU;
}
static inline void guest_exit(void)
{
/* Flush the guest cputime we spent on the guest */
vtime_account_system(current);
current->flags &= ~PF_VCPU;
}
#endif /* CONFIG_VIRT_CPU_ACCOUNTING_GEN */
#endif