wrappers for ->i_mutex access

parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/udf/file.c

@@ -122,7 +122,7 @@ static ssize_t udf_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	struct udf_inode_info *iinfo = UDF_I(inode);
 	int err;
 
-	mutex_lock(&inode->i_mutex);
+	inode_lock(inode);
 
 	retval = generic_write_checks(iocb, from);
 	if (retval <= 0)
@@ -136,7 +136,7 @@ static ssize_t udf_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 				(udf_file_entry_alloc_offset(inode) + end)) {
 			err = udf_expand_file_adinicb(inode);
 			if (err) {
-				mutex_unlock(&inode->i_mutex);
+				inode_unlock(inode);
 				udf_debug("udf_expand_adinicb: err=%d\n", err);
 				return err;
 			}
@@ -149,7 +149,7 @@ static ssize_t udf_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 
 	retval = __generic_file_write_iter(iocb, from);
 out:
-	mutex_unlock(&inode->i_mutex);
+	inode_unlock(inode);
 
 	if (retval > 0) {
 		mark_inode_dirty(inode);
@@ -223,12 +223,12 @@ static int udf_release_file(struct inode *inode, struct file *filp)
 		 * Grab i_mutex to avoid races with writes changing i_size
 		 * while we are running.
 		 */
-		mutex_lock(&inode->i_mutex);
+		inode_lock(inode);
 		down_write(&UDF_I(inode)->i_data_sem);
 		udf_discard_prealloc(inode);
 		udf_truncate_tail_extent(inode);
 		up_write(&UDF_I(inode)->i_data_sem);
-		mutex_unlock(&inode->i_mutex);
+		inode_unlock(inode);
 	}
 	return 0;
 }

fs/udf/inode.c

@@ -262,7 +262,7 @@ int udf_expand_file_adinicb(struct inode *inode)
 		.nr_to_write = 1,
 	};
 
-	WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
+	WARN_ON_ONCE(!inode_is_locked(inode));
 	if (!iinfo->i_lenAlloc) {
 		if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))
 			iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;