nvme: split nvme status from block req->errors

We want our own clearly defined error field for NVMe passthrough commands,
and the request errors field is going away in its current form.

Just store the status and result field in the nvme_request field from
hardirq completion context (using a new helper) and then generate a
Linux errno for the block layer only when we actually need it.

Because we can't overload the status value with a negative error code
for cancelled command we now have a flags filed in struct nvme_request
that contains a bit for this condition.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 14 insertions, 19 deletions

diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index a317461c21d3..d7330f75632d 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -21,16 +21,6 @@
 #include <linux/lightnvm.h>
 #include <linux/sed-opal.h>
 
-enum {
-	/*
-	 * Driver internal status code for commands that were cancelled due
-	 * to timeouts or controller shutdown.  The value is negative so
-	 * that it a) doesn't overlap with the unsigned hardware error codes,
-	 * and b) can easily be tested for.
-	 */
-	NVME_SC_CANCELLED		= -EINTR,
-};
-
 extern unsigned char nvme_io_timeout;
 #define NVME_IO_TIMEOUT	(nvme_io_timeout * HZ)
 
@@ -91,6 +81,12 @@ struct nvme_request {
 	struct nvme_command	*cmd;
 	union nvme_result	result;
 	u8			retries;
+	u8			flags;
+	u16			status;
+};
+
+enum {
+	NVME_REQ_CANCELLED		= (1 << 0),
 };
 
 static inline struct nvme_request *nvme_req(struct request *req)
@@ -248,18 +244,17 @@ static inline void nvme_cleanup_cmd(struct request *req)
 	}
 }
 
-static inline int nvme_error_status(u16 status)
+static inline void nvme_end_request(struct request *req, __le16 status,
+		union nvme_result result)
 {
-	switch (status & 0x7ff) {
-	case NVME_SC_SUCCESS:
-		return 0;
-	case NVME_SC_CAP_EXCEEDED:
-		return -ENOSPC;
-	default:
-		return -EIO;
-	}
+	struct nvme_request *rq = nvme_req(req);
+
+	rq->status = le16_to_cpu(status) >> 1;
+	rq->result = result;
+	blk_mq_complete_request(req, 0);
 }
 
+int nvme_error_status(struct request *req);
 void nvme_complete_rq(struct request *req);
 void nvme_cancel_request(struct request *req, void *data, bool reserved);
 bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,