When driver confirms that the controller is dead, this controller should
be deleted with marking as DEAD. Otherwise, upper layer may wait forever
in __bio_queue_enter() since the disk won't be marked as DEAD.
Especially, in del_gendisk(), disk won't be marked as DEAD unless bdev
sync & invalidate returns. If any writeback IO waits in
__bio_queue_enter(), IO deadlock is caused.
Add nvme_delete_dead_ctrl() for avoiding such kind of io deadlock.
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
drivers/nvme/host/core.c | 24 +++++++++++++++++++++++-
drivers/nvme/host/nvme.h | 1 +
2 files changed, 24 insertions(+), 1 deletion(-)
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index ccb6eb1282f8..413213cfa417 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -227,16 +227,38 @@ static void nvme_delete_ctrl_work(struct work_struct *work)
nvme_do_delete_ctrl(ctrl);
}
-int nvme_delete_ctrl(struct nvme_ctrl *ctrl)
+static int __nvme_delete_ctrl(struct nvme_ctrl *ctrl,
+ enum nvme_ctrl_state state)
{
+ if (state != NVME_CTRL_DELETING && state != NVME_CTRL_DEAD)
+ return -EINVAL;
+
if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_DELETING))
return -EBUSY;
+ if (state == NVME_CTRL_DEAD) {
+ if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_DEAD))
+ return -EBUSY;
+ }
if (!queue_work(nvme_delete_wq, &ctrl->delete_work))
return -EBUSY;
return 0;
}
+
+int nvme_delete_ctrl(struct nvme_ctrl *ctrl)
+{
+ return __nvme_delete_ctrl(ctrl, NVME_CTRL_DELETING);
+}
EXPORT_SYMBOL_GPL(nvme_delete_ctrl);
+/*
+ * Called when driver confirmed that the controller is really dead
+ */
+int nvme_delete_dead_ctrl(struct nvme_ctrl *ctrl)
+{
+ return __nvme_delete_ctrl(ctrl, NVME_CTRL_DEAD);
+}
+EXPORT_SYMBOL_GPL(nvme_delete_dead_ctrl);
+
static void nvme_delete_ctrl_sync(struct nvme_ctrl *ctrl)
{
/*
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index bf46f122e9e1..8f62246a85be 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -828,6 +828,7 @@ void nvme_stop_keep_alive(struct nvme_ctrl *ctrl);
int nvme_reset_ctrl(struct nvme_ctrl *ctrl);
int nvme_reset_ctrl_sync(struct nvme_ctrl *ctrl);
int nvme_delete_ctrl(struct nvme_ctrl *ctrl);
+int nvme_delete_dead_ctrl(struct nvme_ctrl *ctrl);
void nvme_queue_scan(struct nvme_ctrl *ctrl);
int nvme_get_log(struct nvme_ctrl *ctrl, u32 nsid, u8 log_page, u8 lsp, u8 csi,
void *log, size_t size, u64 offset);
--
2.40.1
