[PATCH 09/10] block: reduce ifdef CONFIG_BLOCK madness in headers

From: Christoph Hellwig
Date: Sat Jun 20 2020 - 03:17:19 EST


Large part of bio.h, blkdev.h and genhd.h are under ifdef CONFIG_BLOCK
for no good reason. Only stub out function that are called from
code that is not dependent on CONFIG_BLOCK and leave the harmless
other declarations around.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
include/linux/bio.h | 3 --
include/linux/blkdev.h | 92 ++++++++++++++++++------------------------
include/linux/genhd.h | 14 +++----
3 files changed, 46 insertions(+), 63 deletions(-)

diff --git a/include/linux/bio.h b/include/linux/bio.h
index 91676d4b2dfe77..0282f8aa85935c 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -8,8 +8,6 @@
#include <linux/highmem.h>
#include <linux/mempool.h>
#include <linux/ioprio.h>
-
-#ifdef CONFIG_BLOCK
/* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
#include <linux/blk_types.h>

@@ -824,5 +822,4 @@ static inline void bio_set_polled(struct bio *bio, struct kiocb *kiocb)
bio->bi_opf |= REQ_NOWAIT;
}

-#endif /* CONFIG_BLOCK */
#endif /* __LINUX_BIO_H */
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 973253ce202d87..0f021ee2ce1c3b 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -4,9 +4,6 @@

#include <linux/sched.h>
#include <linux/sched/clock.h>
-
-#ifdef CONFIG_BLOCK
-
#include <linux/major.h>
#include <linux/genhd.h>
#include <linux/list.h>
@@ -1165,13 +1162,13 @@ static inline int blk_rq_map_sg(struct request_queue *q, struct request *rq,
return __blk_rq_map_sg(q, rq, sglist, &last_sg);
}
extern void blk_dump_rq_flags(struct request *, char *);
-extern long nr_blockdev_pages(void);

bool __must_check blk_get_queue(struct request_queue *);
struct request_queue *blk_alloc_queue(make_request_fn make_request, int node_id);
extern void blk_put_queue(struct request_queue *);
extern void blk_set_queue_dying(struct request_queue *);

+#ifdef CONFIG_BLOCK
/*
* blk_plug permits building a queue of related requests by holding the I/O
* fragments for a short period. This allows merging of sequential requests
@@ -1231,9 +1228,47 @@ static inline bool blk_needs_flush_plug(struct task_struct *tsk)
!list_empty(&plug->cb_list));
}

+int blkdev_issue_flush(struct block_device *, gfp_t);
+long nr_blockdev_pages(void);
+#else /* CONFIG_BLOCK */
+struct blk_plug {
+};
+
+static inline void blk_start_plug(struct blk_plug *plug)
+{
+}
+
+static inline void blk_finish_plug(struct blk_plug *plug)
+{
+}
+
+static inline void blk_flush_plug(struct task_struct *task)
+{
+}
+
+static inline void blk_schedule_flush_plug(struct task_struct *task)
+{
+}
+
+
+static inline bool blk_needs_flush_plug(struct task_struct *tsk)
+{
+ return false;
+}
+
+static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask)
+{
+ return 0;
+}
+
+static inline long nr_blockdev_pages(void)
+{
+ return 0;
+}
+#endif /* CONFIG_BLOCK */
+
extern void blk_io_schedule(void);

-int blkdev_issue_flush(struct block_device *, gfp_t);
extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, struct page *page);

@@ -1833,51 +1868,6 @@ static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
}
#endif /* CONFIG_BLK_DEV_ZONED */

-#else /* CONFIG_BLOCK */
-
-struct block_device;
-
-/*
- * stubs for when the block layer is configured out
- */
-
-static inline long nr_blockdev_pages(void)
-{
- return 0;
-}
-
-struct blk_plug {
-};
-
-static inline void blk_start_plug(struct blk_plug *plug)
-{
-}
-
-static inline void blk_finish_plug(struct blk_plug *plug)
-{
-}
-
-static inline void blk_flush_plug(struct task_struct *task)
-{
-}
-
-static inline void blk_schedule_flush_plug(struct task_struct *task)
-{
-}
-
-
-static inline bool blk_needs_flush_plug(struct task_struct *tsk)
-{
- return false;
-}
-
-static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask)
-{
- return 0;
-}
-
-#endif /* CONFIG_BLOCK */
-
static inline void blk_wake_io_task(struct task_struct *waiter)
{
/*
@@ -1891,7 +1881,6 @@ static inline void blk_wake_io_task(struct task_struct *waiter)
wake_up_process(waiter);
}

-#ifdef CONFIG_BLOCK
unsigned long disk_start_io_acct(struct gendisk *disk, unsigned int sectors,
unsigned int op);
void disk_end_io_acct(struct gendisk *disk, unsigned int op,
@@ -1917,7 +1906,6 @@ static inline void bio_end_io_acct(struct bio *bio, unsigned long start_time)
{
return disk_end_io_acct(bio->bi_disk, bio_op(bio), start_time);
}
-#endif /* CONFIG_BLOCK */

int bdev_read_only(struct block_device *bdev);
int set_blocksize(struct block_device *bdev, int size);
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 83f8e0d8322836..31a54072ffd653 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -19,8 +19,6 @@
#include <linux/blk_types.h>
#include <asm/local.h>

-#ifdef CONFIG_BLOCK
-
#define dev_to_disk(device) container_of((device), struct gendisk, part0.__dev)
#define dev_to_part(device) container_of((device), struct hd_struct, __dev)
#define disk_to_dev(disk) (&(disk)->part0.__dev)
@@ -337,12 +335,9 @@ static inline void set_capacity(struct gendisk *disk, sector_t size)
disk->part0.nr_sects = size;
}

-extern dev_t blk_lookup_devt(const char *name, int partno);
-
int bdev_disk_changed(struct block_device *bdev, bool invalidate);
int blk_add_partitions(struct gendisk *disk, struct block_device *bdev);
int blk_drop_partitions(struct block_device *bdev);
-extern void printk_all_partitions(void);

extern struct gendisk *__alloc_disk_node(int minors, int node_id);
extern struct kobject *get_disk_and_module(struct gendisk *disk);
@@ -400,10 +395,13 @@ static inline void bd_unlink_disk_holder(struct block_device *bdev,
}
#endif /* CONFIG_SYSFS */

+#ifdef CONFIG_BLOCK
+void printk_all_partitions(void);
+dev_t blk_lookup_devt(const char *name, int partno);
#else /* CONFIG_BLOCK */
-
-static inline void printk_all_partitions(void) { }
-
+static inline void printk_all_partitions(void)
+{
+}
static inline dev_t blk_lookup_devt(const char *name, int partno)
{
dev_t devt = MKDEV(0, 0);
--
2.26.2