[PATCH 09/11] block: call __bio_free in bio_endio

From: Shaohua Li
Date: Fri Jun 02 2017 - 17:56:03 EST


From: Shaohua Li <shli@xxxxxx>

bio_free isn't a good place to free cgroup/integrity info. There are a
lot of cases bio is allocated in special way (for example, in stack) and
never gets called by bio_put hence bio_free, we are leaking memory. This
patch moves the free to bio endio, which should be called anyway. The
__bio_free call in bio_free is kept, in case the bio never gets called
bio endio.

Signed-off-by: Shaohua Li <shli@xxxxxx>
---
block/bio-integrity.c | 1 +
block/bio.c | 1 +
2 files changed, 2 insertions(+)

diff --git a/block/bio-integrity.c b/block/bio-integrity.c
index 5384713..c6c5aed 100644
--- a/block/bio-integrity.c
+++ b/block/bio-integrity.c
@@ -120,6 +120,7 @@ void bio_integrity_free(struct bio *bio)
}

bio->bi_integrity = NULL;
+ bio->bi_opf &= ~REQ_INTEGRITY;
}
EXPORT_SYMBOL(bio_integrity_free);

diff --git a/block/bio.c b/block/bio.c
index 888e780..02556b3 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1803,6 +1803,7 @@ void bio_endio(struct bio *bio)
if (!bio_remaining_done(bio))
return;

+ __bio_free(bio);
/*
* Need to have a real endio function for chained bios, otherwise
* various corner cases will break (like stacking block devices that
--
2.9.3