From: Hans Holmberg Date: Fri, 5 Jan 2018 13:16:11 +0000 (+0100) Subject: lightnvm: pblk: prevent premature sync point resets X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=b36bbf9d4f731269b4fe88e1060af1e8c28b7972;p=linux.git lightnvm: pblk: prevent premature sync point resets Unless we protect flush pointer updates with a lock, we risk resetting new flush points before we've synced all sectors up to that point. This patch protects new flush points with the same spin lock that is being held when advancing the sync pointer and resetting completed flush points. Signed-off-by: Hans Holmberg Signed-off-by: Javier González Signed-off-by: Matias Bjørling Signed-off-by: Jens Axboe --- diff --git a/drivers/lightnvm/pblk-rb.c b/drivers/lightnvm/pblk-rb.c index 672ef8c478927..ec8fc314646ba 100644 --- a/drivers/lightnvm/pblk-rb.c +++ b/drivers/lightnvm/pblk-rb.c @@ -367,17 +367,17 @@ static int pblk_rb_flush_point_set(struct pblk_rb *rb, struct bio *bio, flush_point = (pos == 0) ? (rb->nr_entries - 1) : (pos - 1); entry = &rb->entries[flush_point]; + pblk_rb_sync_init(rb, NULL); + /* Protect flush points */ smp_store_release(&rb->flush_point, flush_point); - if (!bio) - return 0; + if (bio) + bio_list_add(&entry->w_ctx.bios, bio); - spin_lock_irq(&rb->s_lock); - bio_list_add(&entry->w_ctx.bios, bio); - spin_unlock_irq(&rb->s_lock); + pblk_rb_sync_end(rb, NULL); - return 1; + return bio ? 1 : 0; } static int __pblk_rb_may_write(struct pblk_rb *rb, unsigned int nr_entries,