fscrypt: drop inode argument from fscrypt_get_ctx()

The only reason the inode is being passed to fscrypt_get_ctx() is to
verify that the encryption key is available.  However, all callers
already ensure this because if we get as far as trying to do I/O to an
encrypted file without the key, there's already a bug.

Therefore, remove this unnecessary argument.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index e5194fc..6cf8a34 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -90,7 +90,7 @@ static inline bool fscrypt_dummy_context_enabled(struct inode *inode)
 
 /* crypto.c */
 extern void fscrypt_enqueue_decrypt_work(struct work_struct *);
-extern struct fscrypt_ctx *fscrypt_get_ctx(const struct inode *, gfp_t);
+extern struct fscrypt_ctx *fscrypt_get_ctx(gfp_t);
 extern void fscrypt_release_ctx(struct fscrypt_ctx *);
 extern struct page *fscrypt_encrypt_page(const struct inode *, struct page *,
 						unsigned int, unsigned int,
@@ -247,8 +247,7 @@ static inline void fscrypt_enqueue_decrypt_work(struct work_struct *work)
 {
 }
 
-static inline struct fscrypt_ctx *fscrypt_get_ctx(const struct inode *inode,
-						  gfp_t gfp_flags)
+static inline struct fscrypt_ctx *fscrypt_get_ctx(gfp_t gfp_flags)
 {
 	return ERR_PTR(-EOPNOTSUPP);
 }