2019-05-15 00:41:21

by Heiner Litz

[permalink] [raw]

Subject: [PATCH] lightnvm: pblk: Fix freeing merged pages

---

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 <[email protected]>
---
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 773537804319..88d61b27a9ab 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);
}
}

--
2.17.1

2019-05-15 09:13:28

by Javier González

[permalink] [raw]

Subject: Re: [PATCH] lightnvm: pblk: Fix freeing merged pages

---

> On 15 May 2019, at 02.39, Heiner Litz <[email protected]> wrote:
>
> 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 <[email protected]>
> ---
> 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 773537804319..88d61b27a9ab 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);
> }
> }
>
> --
> 2.17.1

Looks good to me.

Reviewed-by: Javier González <[email protected]>

---

Attachments:

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2019-05-24 14:12:07

by Matias Bjørling

[permalink] [raw]

Subject: Re: [PATCH] lightnvm: pblk: Fix freeing merged pages

---

On 5/15/19 2:39 AM, Heiner Litz wrote:
> 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 <[email protected]>
> ---
> 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 773537804319..88d61b27a9ab 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);
> }
> }
>
>

Thanks Heiner. Picked up for 5.3.