[PATCH 1/8] block: replace disk based account with bdev's

[Ming Lei <ming.lei@xxxxxxxxxx>]

'block device' is generic type for interface, and gendisk becomes more
one block layer internal type, so replace disk based account interface
with bdec's.

Also add 'start_time' parameter to bdev_start_io_acct() so that we
can cover device mapper's io accounting by the two bdev based interface.

Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
 block/blk-core.c              | 15 ++++++++-------
 drivers/block/zram/zram_drv.c |  5 +++--
 include/linux/blkdev.h        |  7 ++++---
 3 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index 937bb6b86331..a3ae13b129ff 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1063,12 +1063,13 @@ unsigned long bio_start_io_acct(struct bio *bio)
 }
 EXPORT_SYMBOL_GPL(bio_start_io_acct);
 
-unsigned long disk_start_io_acct(struct gendisk *disk, unsigned int sectors,
-				 unsigned int op)
+unsigned long bdev_start_io_acct(struct block_device *bdev,
+				 unsigned int sectors, unsigned int op,
+				 unsigned long start_time)
 {
-	return __part_start_io_acct(disk->part0, sectors, op, jiffies);
+	return __part_start_io_acct(bdev, sectors, op, start_time);
 }
-EXPORT_SYMBOL(disk_start_io_acct);
+EXPORT_SYMBOL(bdev_start_io_acct);
 
 static void __part_end_io_acct(struct block_device *part, unsigned int op,
 			       unsigned long start_time)
@@ -1091,12 +1092,12 @@ void bio_end_io_acct_remapped(struct bio *bio, unsigned long start_time,
 }
 EXPORT_SYMBOL_GPL(bio_end_io_acct_remapped);
 
-void disk_end_io_acct(struct gendisk *disk, unsigned int op,
+void bdev_end_io_acct(struct block_device *bdev, unsigned int op,
 		      unsigned long start_time)
 {
-	__part_end_io_acct(disk->part0, op, start_time);
+	__part_end_io_acct(bdev, op, start_time);
 }
-EXPORT_SYMBOL(disk_end_io_acct);
+EXPORT_SYMBOL(bdev_end_io_acct);
 
 /**
  * blk_lld_busy - Check if underlying low-level drivers of a device are busy
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index e9474b02012d..adb5209a556a 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -1675,9 +1675,10 @@ static int zram_rw_page(struct block_device *bdev, sector_t sector,
 	bv.bv_len = PAGE_SIZE;
 	bv.bv_offset = 0;
 
-	start_time = disk_start_io_acct(bdev->bd_disk, SECTORS_PER_PAGE, op);
+	start_time = bdev_start_io_acct(bdev->bd_disk->part0,
+			SECTORS_PER_PAGE, op, jiffies);
 	ret = zram_bvec_rw(zram, &bv, index, offset, op, NULL);
-	disk_end_io_acct(bdev->bd_disk, op, start_time);
+	bdev_end_io_acct(bdev->bd_disk->part0, op, start_time);
 out:
 	/*
 	 * If I/O fails, just return error(ie, non-zero) without
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 60d016138997..f680ba6f0ab2 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1491,9 +1491,10 @@ static inline void blk_wake_io_task(struct task_struct *waiter)
 		wake_up_process(waiter);
 }
 
-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,
+unsigned long bdev_start_io_acct(struct block_device *bdev,
+				 unsigned int sectors, unsigned int op,
+				 unsigned long start_time);
+void bdev_end_io_acct(struct block_device *bdev, unsigned int op,
 		unsigned long start_time);
 
 void bio_start_io_acct_time(struct bio *bio, unsigned long start_time);
-- 
2.31.1