tree 928efbe6ba6efef4e84eed37103038015770614a
parent 27028626b4b9022dcac23688e09ea43b36e1183c
author Shaohua Li <shli@fb.com> 1471925641 -0700
committer Shaohua Li <shli@fb.com> 1472059312 -0700

raid5: fix memory leak of bio integrity data

Yi reported a memory leak of raid5 with DIF/DIX enabled disks. raid5
doesn't alloc/free bio, instead it reuses bios. There are two issues in
current code:
1. the code calls bio_init (from
init_stripe->raid5_build_block->bio_init) then bio_reset (ops_run_io).
The bio is reused, so likely there is integrity data attached. bio_init
will clear a pointer to integrity data and makes bio_reset can't release
the data
2. bio_reset is called before dispatching bio. After bio is finished,
it's possible we don't free bio's integrity data (eg, we don't call
bio_reset again)
Both issues will cause memory leak. The patch moves bio_init to stripe
creation and bio_reset to bio end io. This will fix the two issues.

Reported-by: Yi Zhang <yizhan@redhat.com>
Signed-off-by: Shaohua Li <shli@fb.com>