[5/6] null_blk: discard zones on reset

Commit Message

Damien Le Moal Nov. 9, 2020, 12:51 p.m. UTC

When memory backing is enabled, use null_handle_discard() to free the
backing memory used by a zone when the zone is being reset.

Signed-off-by: Damien Le Moal <[e-mail]>
---
 drivers/block/null_blk.h       | 2 ++
 drivers/block/null_blk_main.c  | 4 ++--
 drivers/block/null_blk_zoned.c | 3 +++
 3 files changed, 7 insertions(+), 2 deletions(-)

Patch

diff --git a/drivers/block/null_blk.h b/drivers/block/null_blk.h
index 683b573b7e14..76bd190fa185 100644
--- a/drivers/block/null_blk.h
+++ b/drivers/block/null_blk.h
@@ -95,6 +95,8 @@  struct nullb {
 	char disk_name[DISK_NAME_LEN];
 };
 
+void null_handle_discard(struct nullb_device *dev, sector_t sector,
+			 sector_t nr_sectors);
 blk_status_t null_process_cmd(struct nullb_cmd *cmd,
 			      enum req_opf op, sector_t sector,
 			      unsigned int nr_sectors);
diff --git a/drivers/block/null_blk_main.c b/drivers/block/null_blk_main.c
index 1483413a81da..2150d6c7d8cd 100644
--- a/drivers/block/null_blk_main.c
+++ b/drivers/block/null_blk_main.c
@@ -1076,8 +1076,8 @@  static void nullb_fill_pattern(struct nullb *nullb, struct page *page,
 	kunmap_atomic(dst);
 }
 
-static void null_handle_discard(struct nullb_device *dev, sector_t sector,
-				sector_t nr_sectors)
+void null_handle_discard(struct nullb_device *dev, sector_t sector,
+			 sector_t nr_sectors)
 {
 	struct nullb *nullb = dev->nullb;
 	size_t n = nr_sectors << SECTOR_SHIFT;
diff --git a/drivers/block/null_blk_zoned.c b/drivers/block/null_blk_zoned.c
index 6f2ad14ef213..d9ae69f722e8 100644
--- a/drivers/block/null_blk_zoned.c
+++ b/drivers/block/null_blk_zoned.c
@@ -595,6 +595,9 @@  static blk_status_t null_reset_zone(struct nullb_device *dev, struct blk_zone *z
 
 	null_unlock_zone_res(dev, flags);
 
+	if (dev->memory_backed)
+		null_handle_discard(dev, zone->start, zone->len);
+
 	return BLK_STS_OK;
 }