[PATCH v5 4/7] block: move main block debugfs initialization to its own file

[Luis Chamberlain <mcgrof@kernel.org>]

make_request-based drivers and and request-based drivers share some
debugfs code. By moving this into its own file it makes it easier
to expand and audit this shared code.

This patch contains no functional changes.

Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Nicolai Stange <nstange@suse.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: yu kuai <yukuai3@huawei.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
---
 block/Makefile      | 10 +++++++---
 block/blk-core.c    |  9 +--------
 block/blk-debugfs.c | 15 +++++++++++++++
 block/blk.h         |  8 ++++++++
 4 files changed, 31 insertions(+), 11 deletions(-)
 create mode 100644 block/blk-debugfs.c

diff --git a/block/Makefile b/block/Makefile
index 78719169fb2a..ec4b17f9dd93 100644
--- a/block/Makefile
+++ b/block/Makefile
@@ -8,7 +8,8 @@ obj-$(CONFIG_BLOCK) := bio.o elevator.o blk-core.o blk-sysfs.o \
 			blk-exec.o blk-merge.o blk-softirq.o blk-timeout.o \
 			blk-lib.o blk-mq.o blk-mq-tag.o blk-stat.o \
 			blk-mq-sysfs.o blk-mq-cpumap.o blk-mq-sched.o ioctl.o \
-			genhd.o ioprio.o badblocks.o partitions/ blk-rq-qos.o
+			genhd.o ioprio.o badblocks.o partitions/ blk-rq-qos.o \
+			debugfs.o
 
 obj-$(CONFIG_BOUNCE)		+= bounce.o
 obj-$(CONFIG_BLK_SCSI_REQUEST)	+= scsi_ioctl.o
@@ -32,8 +33,11 @@ obj-$(CONFIG_BLK_MQ_VIRTIO)	+= blk-mq-virtio.o
 obj-$(CONFIG_BLK_MQ_RDMA)	+= blk-mq-rdma.o
 obj-$(CONFIG_BLK_DEV_ZONED)	+= blk-zoned.o
 obj-$(CONFIG_BLK_WBT)		+= blk-wbt.o
-obj-$(CONFIG_BLK_DEBUG_FS)	+= blk-mq-debugfs.o
-obj-$(CONFIG_BLK_DEBUG_FS_ZONED)+= blk-mq-debugfs-zoned.o
+
+debugfs-$(CONFIG_DEBUG_FS)		+= blk-debugfs.o
+debugfs-$(CONFIG_BLK_DEBUG_FS)		+= blk-mq-debugfs.o
+debugfs-$(CONFIG_BLK_DEBUG_FS_ZONED)	+= blk-mq-debugfs-zoned.o
+
 obj-$(CONFIG_BLK_SED_OPAL)	+= sed-opal.o
 obj-$(CONFIG_BLK_PM)		+= blk-pm.o
 obj-$(CONFIG_BLK_INLINE_ENCRYPTION)	+= keyslot-manager.o blk-crypto.o
diff --git a/block/blk-core.c b/block/blk-core.c
index 8a785d16033b..d40648958767 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -51,10 +51,6 @@
 #include "blk-pm.h"
 #include "blk-rq-qos.h"
 
-#ifdef CONFIG_DEBUG_FS
-struct dentry *blk_debugfs_root;
-#endif
-
 EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_remap);
 EXPORT_TRACEPOINT_SYMBOL_GPL(block_rq_remap);
 EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_complete);
@@ -1880,10 +1876,7 @@ int __init blk_dev_init(void)
 
 	blk_requestq_cachep = kmem_cache_create("request_queue",
 			sizeof(struct request_queue), 0, SLAB_PANIC, NULL);
-
-#ifdef CONFIG_DEBUG_FS
-	blk_debugfs_root = debugfs_create_dir("block", NULL);
-#endif
+	blk_debugfs_register();
 
 	return 0;
 }
diff --git a/block/blk-debugfs.c b/block/blk-debugfs.c
new file mode 100644
index 000000000000..19091e1effc0
--- /dev/null
+++ b/block/blk-debugfs.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Shared request-based / make_request-based functionality
+ */
+#include <linux/kernel.h>
+#include <linux/blkdev.h>
+#include <linux/debugfs.h>
+
+struct dentry *blk_debugfs_root;
+
+void blk_debugfs_register(void)
+{
+	blk_debugfs_root = debugfs_create_dir("block", NULL);
+}
diff --git a/block/blk.h b/block/blk.h
index fc00537026a0..ee309233f95e 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -458,4 +458,12 @@ int bio_add_hw_page(struct request_queue *q, struct bio *bio,
 		struct page *page, unsigned int len, unsigned int offset,
 		unsigned int max_sectors, bool *same_page);
 
+#ifdef CONFIG_DEBUG_FS
+void blk_debugfs_register(void);
+#else
+static inline void blk_debugfs_register(void)
+{
+}
+#endif /* CONFIG_DEBUG_FS */
+
 #endif /* BLK_INTERNAL_H */
-- 
2.26.2