tmpfs: miscellaneous trivial cleanups

While it's at its least, make a number of boring nitpicky cleanups to
shmem.c, mostly for consistency of variable naming.  Things like "swap"
instead of "entry", "pgoff_t index" instead of "unsigned long idx".

And since everything else here is prefixed "shmem_", better change
init_tmpfs() to shmem_init().
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/shmem_fs.h

@@ -47,7 +47,7 @@ static inline struct shmem_inode_info *SHMEM_I(struct inode *inode)
 /*
  * Functions in mm/shmem.c called directly from elsewhere:
  */
-extern int init_tmpfs(void);
+extern int shmem_init(void);
 extern int shmem_fill_super(struct super_block *sb, void *data, int silent);
 extern struct file *shmem_file_setup(const char *name,
 					loff_t size, unsigned long flags);

init/main.c

@@ -715,7 +715,7 @@ static void __init do_basic_setup(void)
 {
 	cpuset_init_smp();
 	usermodehelper_init();
-	init_tmpfs();
+	shmem_init();
 	driver_init();
 	init_irq_proc();
 	do_ctors();