[PATCH AUTOSEL 5.4 330/330] nvme: explicitly update mpath disk capacity on revalidation

[Sasha Levin]

From: Anthony Iliopoulos <ailiop@xxxxxxxx>

[ Upstream commit 05b29021fba5e725dd385151ef00b6340229b500 ]

Commit 3b4b19721ec652 ("nvme: fix possible deadlock when I/O is
blocked") reverted multipath head disk revalidation due to deadlocks
caused by holding the bd_mutex during revalidate.

Updating the multipath disk blockdev size is still required though for
userspace to be able to observe any resizing while the device is
mounted. Directly update the bdev inode size to avoid unnecessarily
holding the bdev->bd_mutex.

Fixes: 3b4b19721ec652 ("nvme: fix possible deadlock when I/O is
blocked")

Signed-off-by: Anthony Iliopoulos <ailiop@xxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/nvme/host/core.c |  1 +
 drivers/nvme/host/nvme.h | 13 +++++++++++++
 2 files changed, 14 insertions(+)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index bbf52e88f045a..038ef9d113388 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -1864,6 +1864,7 @@ static void __nvme_revalidate_disk(struct gendisk *disk, struct nvme_id_ns *id)
 	if (ns->head->disk) {
 		nvme_update_disk_info(ns->head->disk, ns, id);
 		blk_queue_stack_limits(ns->head->disk->queue, ns->queue);
+		nvme_mpath_update_disk_size(ns->head->disk);
 	}
 #endif
 }
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index 7d57c42a641ca..aab976737f9a9 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -561,6 +561,16 @@ static inline void nvme_trace_bio_complete(struct request *req,
 					 req->bio, status);
 }
 
+static inline void nvme_mpath_update_disk_size(struct gendisk *disk)
+{
+	struct block_device *bdev = bdget_disk(disk, 0);
+
+	if (bdev) {
+		bd_set_size(bdev, get_capacity(disk) << SECTOR_SHIFT);
+		bdput(bdev);
+	}
+}
+
 extern struct device_attribute dev_attr_ana_grpid;
 extern struct device_attribute dev_attr_ana_state;
 extern struct device_attribute subsys_attr_iopolicy;
@@ -636,6 +646,9 @@ static inline void nvme_mpath_wait_freeze(struct nvme_subsystem *subsys)
 static inline void nvme_mpath_start_freeze(struct nvme_subsystem *subsys)
 {
 }
+static inline void nvme_mpath_update_disk_size(struct gendisk *disk)
+{
+}
 #endif /* CONFIG_NVME_MULTIPATH */
 
 #ifdef CONFIG_NVM
-- 
2.25.1