Currently, devices like md, bcache uses disk_[start|end]_io_acct to report iostat. These functions couldn't get proper iostat for partitions on these devices. This set resolves this issue by introducing part_[begin|end]_io_acct, and using them in md and bcache code. Changes v2 => v3: 1. Use EXPORT_SYMBOL_GPL() instead of EXPORT_SYMBOL(). 2. Include Christoph's Reviewed-by tag. Changes v1 => v2: 1. Refactor the code, as suggested by Christoph. 2. Include Coly's Reviewed-by tag. Song Liu (3): block: introduce part_[begin|end]_io_acct md: use part_[begin|end]_io_acct instead of disk_[begin|end]_io_acct bcache: use part_[begin|end]_io_acct instead of disk_[begin|end]_io_acct block/blk-core.c | 39 +++++++++++++++++++++++++++++++------ drivers/md/bcache/request.c | 10 ++++++---- drivers/md/md.c | 8 ++++---- include/linux/blkdev.h | 5 +++++ 4 files changed, 48 insertions(+), 14 deletions(-) -- 2.24.1