Re: [PATCH] md: factor out cloned bio cleanup into md_free_bio()

From: Abd-Alrhman Masalkhi

Date: Wed Apr 15 2026 - 03:52:55 EST


On Wed, Apr 15, 2026 at 10:27 +0800, Li Nan wrote:
> 在 2026/4/14 18:38, Abd-Alrhman Masalkhi 写道:
>> Refactor duplicated cloned bio completion and cleanup logic into
>> a new helper, md_free_bio().
>>
>> md_end_clone_io() and md_free_cloned_bio() previously shared nearly
>> identical teardown code, differing only in whether the original
>> bio’s endio callback was invoked. Introduce a boolean parameter
>> orig_endio to control this behavior and consolidate the logic.
>>
>> Signed-off-by: Abd-Alrhman Masalkhi <abd.masalkhi@xxxxxxxxx>
>> ---
>> drivers/md/md.c | 26 +++++++++-----------------
>> 1 file changed, 9 insertions(+), 17 deletions(-)
>>
>> diff --git a/drivers/md/md.c b/drivers/md/md.c
>> index ac71640ff3a8..707d605fee61 100644
>> --- a/drivers/md/md.c
>> +++ b/drivers/md/md.c
>> @@ -9208,7 +9208,7 @@ static void md_bitmap_end(struct mddev *mddev, struct md_io_clone *md_io_clone)
>> fn(mddev, md_io_clone->offset, md_io_clone->sectors);
>> }
>>
>> -static void md_end_clone_io(struct bio *bio)
>> +static void md_free_bio(struct bio *bio, bool orig_endio)
>> {
>> struct md_io_clone *md_io_clone = bio->bi_private;
>> struct bio *orig_bio = md_io_clone->orig_bio;
>> @@ -9224,10 +9224,16 @@ static void md_end_clone_io(struct bio *bio)
>> bio_end_io_acct(orig_bio, md_io_clone->start_time);
>>
>> bio_put(bio);
>> - bio_endio(orig_bio);
>> + if (orig_endio)
>> + bio_endio(orig_bio);
>> percpu_ref_put(&mddev->active_io);
>> }
>>
>> +static void md_end_clone_io(struct bio *bio)
>> +{
>> + md_free_bio(bio, true);
>> +}
>> +
>> static void md_clone_bio(struct mddev *mddev, struct bio **bio)
>> {
>> struct block_device *bdev = (*bio)->bi_bdev;
>> @@ -9262,21 +9268,7 @@ EXPORT_SYMBOL_GPL(md_account_bio);
>>
>> void md_free_cloned_bio(struct bio *bio)
>> {
>> - struct md_io_clone *md_io_clone = bio->bi_private;
>> - struct bio *orig_bio = md_io_clone->orig_bio;
>> - struct mddev *mddev = md_io_clone->mddev;
>> -
>> - if (bio_data_dir(orig_bio) == WRITE && md_bitmap_enabled(mddev, false))
>> - md_bitmap_end(mddev, md_io_clone);
>> -
>> - if (bio->bi_status && !orig_bio->bi_status)
>> - orig_bio->bi_status = bio->bi_status;
>> -
>> - if (md_io_clone->start_time)
>> - bio_end_io_acct(orig_bio, md_io_clone->start_time);
>> -
>> - bio_put(bio);
>> - percpu_ref_put(&mddev->active_io);
>> + md_free_bio(bio, false);
>> }
>> EXPORT_SYMBOL_GPL(md_free_cloned_bio);
>>
>
> md_free_bio() is redundant. Can md_end_clone_io() directly call
> md_free_cloned_bio()?
>
> We do not need to consider the compatibility of the EXPORT_SYMBOL in
> mainline.
>
Thanks for the feedback!

You're right, this can be simplified. I'll send a v2 shortly.
> --
> Thanks,
> Nan
>

--
Best Regards,
Abd-Alrhman