[Devel] [PATCH VZ9 v3 08/13] dm-ploop: make new allocations immediately visible in BAT

[Andrey Zhadchenko]

We are planning to delay metadata writeback, so we want to
immediately apply metadata changes to BAT page.
Make all request that trigger PIWB_TYPE_RELOC apply metadata
changes immediately.

https://virtuozzo.atlassian.net/browse/VSTOR-91817
Signed-off-by: Andrey Zhadchenko <andrey.zhadchenko at virtuozzo.com>
---
 drivers/md/dm-ploop-map.c | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/drivers/md/dm-ploop-map.c b/drivers/md/dm-ploop-map.c
index 76d344a7bcad..fb16f7e66dd2 100644
--- a/drivers/md/dm-ploop-map.c
+++ b/drivers/md/dm-ploop-map.c
@@ -762,6 +762,10 @@ static void ploop_advance_local_after_bat_wb(struct ploop *ploop,
 
 	dst_clu = piwb->kmpage;
 
+	write_lock_irqsave(&md->lock, flags);
+	if (piwb->type == PIWB_TYPE_ALLOC)
+		goto skip_apply;
+
 	for (; i < last; i++) {
 		if (piwb->type == PIWB_TYPE_DISCARD) {
 			ploop_piwb_discard_completed(ploop, success, i + off, dst_clu[i]);
@@ -771,12 +775,6 @@ static void ploop_advance_local_after_bat_wb(struct ploop *ploop,
 		if (!dst_clu[i])
 			continue;
 
-		if (ploop_cluster_is_in_top_delta(ploop, i + off)
-						&& piwb->type == PIWB_TYPE_ALLOC) {
-			WARN_ON(bat_entries[i] != dst_clu[i]);
-			continue;
-		}
-
 		if (success) {
 			bat_entries[i] = READ_ONCE(dst_clu[i]);
 			WRITE_ONCE(md->bat_levels[i], ploop_top_level(ploop));
@@ -784,11 +782,10 @@ static void ploop_advance_local_after_bat_wb(struct ploop *ploop,
 			ploop_hole_set_bit(i + off, ploop);
 		}
 	}
+skip_apply:
 
 	WARN_ON_ONCE(!test_bit(MD_WRITEBACK, &md->status));
 	clear_bit(MD_WRITEBACK, &md->status);
-	/* protect piwb */
-	write_lock_irqsave(&md->lock, flags);
 	md->piwb = NULL;
 	write_unlock_irqrestore(&md->lock, flags);
 
@@ -1123,6 +1120,8 @@ static int ploop_alloc_cluster(struct ploop *ploop, struct ploop_index_wb *piwb,
 
 	to = piwb->kmpage;
 	WRITE_ONCE(to[clu], *dst_clu);
+	to = piwb->md->kmpage;
+	WRITE_ONCE(to[clu], *dst_clu);
 out:
 	return ret;
 }
@@ -1379,6 +1378,7 @@ static void ploop_submit_cow_index_wb(struct ploop_cow *cow)
 	u32 page_id, clu = cow_pio->clu;
 	struct ploop_index_wb *piwb;
 	struct md_page *md;
+	unsigned long flags;
 	map_index_t *to;
 
 	WARN_ON_ONCE(cow->aux_pio->queue_list_id != PLOOP_LIST_COW);
@@ -1403,6 +1403,12 @@ static void ploop_submit_cow_index_wb(struct ploop_cow *cow)
 	WARN_ON(to[clu]);
 	WRITE_ONCE(to[clu], cow->dst_clu);
 
+	write_lock_irqsave(&md->lock, flags);
+	to = md->kmpage;
+	WRITE_ONCE(to[clu], cow->dst_clu);
+	WRITE_ONCE(md->bat_levels[clu], ploop_top_level(ploop));
+	write_unlock_irqrestore(&md->lock, flags);
+
 	/* Prevent double clearing of holes_bitmap bit on complete_cow() */
 	cow->dst_clu = BAT_ENTRY_NONE;
 	spin_lock_irq(&ploop->deferred_lock);
-- 
2.39.3