[GIT PULL 07/58] lightnvm: pblk: protect line bitmap while submitting meta io

From: Matias BjÃrling
Date: Fri Oct 13 2017 - 08:47:26 EST


From: Rakesh Pandit <rakesh@xxxxxxxxxx>

It seems pblk_dealloc_page would race against pblk_alloc_pages for
line bitmap for sector allocation.The chances are very low but might
as well protect the bitmap properly.

Signed-off-by: Rakesh Pandit <rakesh@xxxxxxxxxx>
Reviewed-by: Javier GonzÃlez <javier@xxxxxxxxxxxx>
Signed-off-by: Matias BjÃrling <m@xxxxxxxxxxx>
---
drivers/lightnvm/pblk-core.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/lightnvm/pblk-core.c b/drivers/lightnvm/pblk-core.c
index 8150164..b53bb00 100644
--- a/drivers/lightnvm/pblk-core.c
+++ b/drivers/lightnvm/pblk-core.c
@@ -486,12 +486,14 @@ void pblk_dealloc_page(struct pblk *pblk, struct pblk_line *line, int nr_secs)
u64 addr;
int i;

+ spin_lock(&line->lock);
addr = find_next_zero_bit(line->map_bitmap,
pblk->lm.sec_per_line, line->cur_sec);
line->cur_sec = addr - nr_secs;

for (i = 0; i < nr_secs; i++, line->cur_sec--)
WARN_ON(!test_and_clear_bit(line->cur_sec, line->map_bitmap));
+ spin_unlock(&line->lock);
}

u64 __pblk_alloc_page(struct pblk *pblk, struct pblk_line *line, int nr_secs)
--
2.9.3