[PATCH V4 1/5] nvme: do atomically bit operations on nvme_request.flags

[Jianchao Wang]

Do atomically bit operations on nvme_request.flags instead of
regular read/write, then we could add other flags and set/clear
them safely.

Signed-off-by: Jianchao Wang <jianchao.w.wang at oracle.com>
---
 drivers/nvme/host/core.c     | 4 ++--
 drivers/nvme/host/lightnvm.c | 4 ++--
 drivers/nvme/host/nvme.h     | 4 ++--
 drivers/nvme/host/pci.c      | 4 ++--
 4 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 29ead91..7b8df47 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -674,7 +674,7 @@ int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
 	blk_execute_rq(req->q, NULL, req, at_head);
 	if (result)
 		*result = nvme_req(req)->result;
-	if (nvme_req(req)->flags & NVME_REQ_CANCELLED)
+	if (test_bit(NVME_REQ_CANCELLED, &nvme_req(req)->flags))
 		ret = -EINTR;
 	else
 		ret = nvme_req(req)->status;
@@ -763,7 +763,7 @@ static int nvme_submit_user_cmd(struct request_queue *q,
 	}
 
 	blk_execute_rq(req->q, disk, req, 0);
-	if (nvme_req(req)->flags & NVME_REQ_CANCELLED)
+	if (test_bit(NVME_REQ_CANCELLED, &nvme_req(req)->flags))
 		ret = -EINTR;
 	else
 		ret = nvme_req(req)->status;
diff --git a/drivers/nvme/host/lightnvm.c b/drivers/nvme/host/lightnvm.c
index 50ef71ee..fd0c499 100644
--- a/drivers/nvme/host/lightnvm.c
+++ b/drivers/nvme/host/lightnvm.c
@@ -470,7 +470,7 @@ static int nvme_nvm_submit_io_sync(struct nvm_dev *dev, struct nvm_rq *rqd)
 	 * handle the error accordingly.
 	 */
 	blk_execute_rq(q, NULL, rq, 0);
-	if (nvme_req(rq)->flags & NVME_REQ_CANCELLED)
+	if (test_bit(NVME_REQ_CANCELLED, &nvme_req(rq)->flags))
 		ret = -EINTR;
 
 	rqd->ppa_status = le64_to_cpu(nvme_req(rq)->result.u64);
@@ -599,7 +599,7 @@ static int nvme_nvm_submit_user_cmd(struct request_queue *q,
 
 	blk_execute_rq(q, NULL, rq, 0);
 
-	if (nvme_req(rq)->flags & NVME_REQ_CANCELLED)
+	if (test_bit(NVME_REQ_CANCELLED, &nvme_req(rq)->flags))
 		ret = -EINTR;
 	else if (nvme_req(rq)->status & 0x7ff)
 		ret = -EIO;
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index e80fd74..02097e8 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -93,8 +93,8 @@ struct nvme_request {
 	struct nvme_command	*cmd;
 	union nvme_result	result;
 	u8			retries;
-	u8			flags;
 	u16			status;
+	unsigned long flags;
 };
 
 /*
@@ -103,7 +103,7 @@ struct nvme_request {
 #define REQ_NVME_MPATH		REQ_DRV
 
 enum {
-	NVME_REQ_CANCELLED		= (1 << 0),
+	NVME_REQ_CANCELLED		= 0,
 };
 
 static inline struct nvme_request *nvme_req(struct request *req)
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 73036d2..e186158 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1222,7 +1222,7 @@ static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
 			 "I/O %d QID %d timeout, disable controller\n",
 			 req->tag, nvmeq->qid);
 		nvme_dev_disable(dev, false);
-		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
+		set_bit(NVME_REQ_CANCELLED, &nvme_req(req)->flags);
 		return BLK_EH_HANDLED;
 	default:
 		break;
@@ -1244,7 +1244,7 @@ static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
 		 * Mark the request as handled, since the inline shutdown
 		 * forces all outstanding requests to complete.
 		 */
-		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
+		set_bit(NVME_REQ_CANCELLED, &nvme_req(req)->flags);
 		return BLK_EH_HANDLED;
 	}
 
-- 
2.7.4