[PATCH] fs: remove the special !CONFIG_BLOCK def_blk_fops

[PATCH] fs: remove the special !CONFIG_BLOCK def_blk_fops

[Christoph Hellwig]

def_blk_fops always returns -ENODEV, which dosn't match the return value
of a non-existing block device with CONFIG_BLOCK, which is -ENXIO.
Just remove the extra implementation and fall back to the default
no_open_fops that always returns -ENXIO.

Fixes: 9361401eb761 ("[PATCH] BLOCK: Make it possible to disable the block layer [try #6]")
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/Makefile   | 10 ++--------
 fs/inode.c    |  3 ++-
 fs/no-block.c | 19 -------------------
 3 files changed, 4 insertions(+), 28 deletions(-)
 delete mode 100644 fs/no-block.c

diff --git a/fs/Makefile b/fs/Makefile
index 834f1c3dba4642..4709eba1303c60 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -17,14 +17,8 @@ obj-y :=	open.o read_write.o file_table.o super.o \
 		fs_types.o fs_context.o fs_parser.o fsopen.o init.o \
 		kernel_read_file.o mnt_idmapping.o remap_range.o
 
-ifeq ($(CONFIG_BLOCK),y)
-obj-y +=	buffer.o mpage.o
-else
-obj-y +=	no-block.o
-endif
-
-obj-$(CONFIG_PROC_FS) += proc_namespace.o
-
+obj-$(CONFIG_BLOCK)		+= buffer.o mpage.o
+obj-$(CONFIG_PROC_FS)		+= proc_namespace.o
 obj-$(CONFIG_LEGACY_DIRECT_IO)	+= direct-io.o
 obj-y				+= notify/
 obj-$(CONFIG_EPOLL)		+= eventpoll.o
diff --git a/fs/inode.c b/fs/inode.c
index 577799b7855f6f..4d6a1544e95b7f 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -2264,7 +2264,8 @@ void init_special_inode(struct inode *inode, umode_t mode, dev_t rdev)
 		inode->i_fop = &def_chr_fops;
 		inode->i_rdev = rdev;
 	} else if (S_ISBLK(mode)) {
-		inode->i_fop = &def_blk_fops;
+		if (IS_ENABLED(CONFIG_BLOCK))
+			inode->i_fop = &def_blk_fops;
 		inode->i_rdev = rdev;
 	} else if (S_ISFIFO(mode))
 		inode->i_fop = &pipefifo_fops;
diff --git a/fs/no-block.c b/fs/no-block.c
deleted file mode 100644
index 481c0f0ab4bd2c..00000000000000
--- a/fs/no-block.c
+++ /dev/null
@@ -1,19 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* no-block.c: implementation of routines required for non-BLOCK configuration
- *
- * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-
-#include <linux/kernel.h>
-#include <linux/fs.h>
-
-static int no_blkdev_open(struct inode * inode, struct file * filp)
-{
-	return -ENODEV;
-}
-
-const struct file_operations def_blk_fops = {
-	.open		= no_blkdev_open,
-	.llseek		= noop_llseek,
-};
-- 
2.39.2

Re: [PATCH] fs: remove the special !CONFIG_BLOCK def_blk_fops

[Christoph Hellwig]

Jens, can you pick this one up?

Re: [PATCH] fs: remove the special !CONFIG_BLOCK def_blk_fops

[Jens Axboe]

On Mon, 08 May 2023 07:44:05 -0700, Christoph Hellwig wrote:
> def_blk_fops always returns -ENODEV, which dosn't match the return value
> of a non-existing block device with CONFIG_BLOCK, which is -ENXIO.
> Just remove the extra implementation and fall back to the default
> no_open_fops that always returns -ENXIO.
> 
> 

Applied, thanks!

[1/1] fs: remove the special !CONFIG_BLOCK def_blk_fops
      commit: bda2795a630b2f6c417675bfbf4d90ef7503dfc7

Best regards,
-- 
Jens Axboe