[PATCH AUTOSEL 5.1 121/219] lightnvm: pblk: fix freeing of merged pages

Sasha Levin
2019-07-15T14:10:41Z

From: Heiner Litz <hlitz@ucsc.edu>

[ Upstream commit 510fd8ea98fcb586c01aef93d87c060a159ac30a ]

bio_add_pc_page() may merge pages when a bio is padded due to a flush.
Fix iteration over the bio to free the correct pages in case of a merge.

Signed-off-by: Heiner Litz <hlitz@ucsc.edu>
Reviewed-by: Javier González <javier@javigon.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/lightnvm/pblk-core.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/drivers/lightnvm/pblk-core.c b/drivers/lightnvm/pblk-core.c
index 6ca868868fee..7393d64757a1 100644
--- a/drivers/lightnvm/pblk-core.c
+++ b/drivers/lightnvm/pblk-core.c
@@ -323,14 +323,16 @@ void pblk_free_rqd(struct pblk *pblk, struct nvm_rq *rqd, int type)
void pblk_bio_free_pages(struct pblk *pblk, struct bio *bio, int off,
int nr_pages)
{
- struct bio_vec bv;
- int i;
-
- WARN_ON(off + nr_pages != bio->bi_vcnt);
-
- for (i = off; i < nr_pages + off; i++) {
- bv = bio->bi_io_vec[i];
- mempool_free(bv.bv_page, &pblk->page_bio_pool);
+ struct bio_vec *bv;
+ struct page *page;
+ int i, e, nbv = 0;
+
+ for (i = 0; i < bio->bi_vcnt; i++) {
+ bv = &bio->bi_io_vec[i];
+ page = bv->bv_page;
+ for (e = 0; e < bv->bv_len; e += PBLK_EXPOSED_PAGE_SIZE, nbv++)
+ if (nbv >= off)
+ mempool_free(page++, &pblk->page_bio_pool);
}
}

--
2.20.1