ipc/shm.c: is_file_shm_hugepages() can be boolean

Make is_file_shm_hugepages() return bool to improve readability due to
this particular function only using either one or zero as its return
value.

No functional change.

Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/shm.h

@@ -52,7 +52,7 @@ struct sysv_shm {
 
 long do_shmat(int shmid, char __user *shmaddr, int shmflg, unsigned long *addr,
 	      unsigned long shmlba);
-int is_file_shm_hugepages(struct file *file);
+bool is_file_shm_hugepages(struct file *file);
 void exit_shm(struct task_struct *task);
 #define shm_init_task(task) INIT_LIST_HEAD(&(task)->sysvshm.shm_clist)
 #else
@@ -66,9 +66,9 @@ static inline long do_shmat(int shmid, char __user *shmaddr,
 {
 	return -ENOSYS;
 }
-static inline int is_file_shm_hugepages(struct file *file)
+static inline bool is_file_shm_hugepages(struct file *file)
 {
-	return 0;
+	return false;
 }
 static inline void exit_shm(struct task_struct *task)
 {

ipc/shm.c

@@ -459,7 +459,7 @@ static const struct file_operations shm_file_operations_huge = {
 	.fallocate	= shm_fallocate,
 };
 
-int is_file_shm_hugepages(struct file *file)
+bool is_file_shm_hugepages(struct file *file)
 {
 	return file->f_op == &shm_file_operations_huge;
 }