fs/ecryptfs/: possible cleanups

- make the following needlessly global code static:
  - crypto.c:ecryptfs_lower_offset_for_extent()
  - crypto.c:key_tfm_list
  - crypto.c:key_tfm_list_mutex
  - inode.c:ecryptfs_getxattr()
  - main.c:ecryptfs_init_persistent_file()

- remove the no longer used mmap.c:ecryptfs_lower_page_cache

- #if 0 the unused read_write.c:ecryptfs_read()

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
index f8ef0af..5e7d018 100644
--- a/fs/ecryptfs/crypto.c
+++ b/fs/ecryptfs/crypto.c
@@ -376,8 +376,8 @@
  *
  * Convert an eCryptfs page index into a lower byte offset
  */
-void ecryptfs_lower_offset_for_extent(loff_t *offset, loff_t extent_num,
-				      struct ecryptfs_crypt_stat *crypt_stat)
+static void ecryptfs_lower_offset_for_extent(loff_t *offset, loff_t extent_num,
+					     struct ecryptfs_crypt_stat *crypt_stat)
 {
 	(*offset) = ((crypt_stat->extent_size
 		      * crypt_stat->num_header_extents_at_front)
@@ -1802,8 +1802,8 @@
 }
 
 struct kmem_cache *ecryptfs_key_tfm_cache;
-struct list_head key_tfm_list;
-struct mutex key_tfm_list_mutex;
+static struct list_head key_tfm_list;
+static struct mutex key_tfm_list_mutex;
 
 int ecryptfs_init_crypto(void)
 {