forked from mirrors/linux
		
	Move set_notify_resume and tracehook_notify_resume into resume_user_mode.h. While doing that rename tracehook_notify_resume to resume_user_mode_work. Update all of the places that included tracehook.h for these functions to include resume_user_mode.h instead. Update all of the callers of tracehook_notify_resume to call resume_user_mode_work. Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lkml.kernel.org/r/20220309162454.123006-12-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
		
			
				
	
	
		
			64 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			64 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* SPDX-License-Identifier: GPL-2.0-only */
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#ifndef LINUX_RESUME_USER_MODE_H
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#define LINUX_RESUME_USER_MODE_H
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#include <linux/sched.h>
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#include <linux/task_work.h>
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#include <linux/memcontrol.h>
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#include <linux/blk-cgroup.h>
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/**
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 * set_notify_resume - cause resume_user_mode_work() to be called
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 * @task:		task that will call resume_user_mode_work()
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 *
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 * Calling this arranges that @task will call resume_user_mode_work()
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 * before returning to user mode.  If it's already running in user mode,
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 * it will enter the kernel and call resume_user_mode_work() soon.
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 * If it's blocked, it will not be woken.
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 */
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static inline void set_notify_resume(struct task_struct *task)
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{
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	if (!test_and_set_tsk_thread_flag(task, TIF_NOTIFY_RESUME))
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		kick_process(task);
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}
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/**
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 * resume_user_mode_work - Perform work before returning to user mode
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 * @regs:		user-mode registers of @current task
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 *
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 * This is called when %TIF_NOTIFY_RESUME has been set.  Now we are
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 * about to return to user mode, and the user state in @regs can be
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 * inspected or adjusted.  The caller in arch code has cleared
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 * %TIF_NOTIFY_RESUME before the call.  If the flag gets set again
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 * asynchronously, this will be called again before we return to
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 * user mode.
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 *
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 * Called without locks.
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 */
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static inline void resume_user_mode_work(struct pt_regs *regs)
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{
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	clear_thread_flag(TIF_NOTIFY_RESUME);
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	/*
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	 * This barrier pairs with task_work_add()->set_notify_resume() after
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	 * hlist_add_head(task->task_works);
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	 */
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	smp_mb__after_atomic();
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	if (unlikely(task_work_pending(current)))
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		task_work_run();
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#ifdef CONFIG_KEYS_REQUEST_CACHE
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	if (unlikely(current->cached_requested_key)) {
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		key_put(current->cached_requested_key);
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		current->cached_requested_key = NULL;
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	}
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#endif
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	mem_cgroup_handle_over_high();
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	blkcg_maybe_throttle_current();
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	rseq_handle_notify_resume(NULL, regs);
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}
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#endif /* LINUX_RESUME_USER_MODE_H */
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