Commit 864bdb3b authored by Al Viro's avatar Al Viro
Browse files

new helper: daemonize_descriptors() 



descriptor-related parts of daemonize, done right.  As the
result we simplify the locking rules for ->files - we
hold task_lock in *all* cases when we modify ->files.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 2be7fd55

fs/file.c

+6 −0
Original line number Diff line number Diff line
@@ -519,6 +519,12 @@ struct files_struct init_files = { 
	.file_lock	= __SPIN_LOCK_UNLOCKED(init_task.file_lock),

};



void daemonize_descriptors(void)

{

	atomic_inc(&init_files.count);

	reset_files_struct(&init_files);

}



/*

 * allocate a file descriptor, mark it busy.

 */

include/linux/fdtable.h

+1 −0
Original line number Diff line number Diff line
@@ -95,6 +95,7 @@ struct task_struct; 
struct files_struct *get_files_struct(struct task_struct *);

void put_files_struct(struct files_struct *fs);

void reset_files_struct(struct files_struct *);

void daemonize_descriptors(void);

int unshare_files(struct files_struct **);

struct files_struct *dup_fd(struct files_struct *, int *);

void do_close_on_exec(struct files_struct *);

kernel/exit.c

+1 −3
Original line number Diff line number Diff line
@@ -457,9 +457,7 @@ void daemonize(const char *name, ...) 
	/* Become as one with the init task */



	daemonize_fs_struct();

	exit_files(current);

	current->files = init_task.files;

	atomic_inc(&current->files->count);

	daemonize_descriptors();



	reparent_to_kthreadd();

}