nvmet: support fabrics sq flow control

[linux.git] / drivers / nvme / target / core.c

diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
index 5aa5a3cc53953a23a1a1f029cb85cf206577c1bb..2df70010e9f29224dc5f3e28bf1c071ed94c4f0e 100644 (file)
--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -597,26 +597,28 @@ struct nvmet_ns *nvmet_ns_alloc(struct nvmet_subsys *subsys, u32 nsid)
        return ns;
 }
 
-static void __nvmet_req_complete(struct nvmet_req *req, u16 status)
+static void nvmet_update_sq_head(struct nvmet_req *req)
 {
-       u32 old_sqhd, new_sqhd;
-       u16 sqhd;
-
-       if (status)
-               nvmet_set_status(req, status);
-
        if (req->sq->size) {
+               u32 old_sqhd, new_sqhd;
+
                do {
                        old_sqhd = req->sq->sqhd;
                        new_sqhd = (old_sqhd + 1) % req->sq->size;
                } while (cmpxchg(&req->sq->sqhd, old_sqhd, new_sqhd) !=
                                        old_sqhd);
        }
-       sqhd = req->sq->sqhd & 0x0000FFFF;
-       req->rsp->sq_head = cpu_to_le16(sqhd);
+       req->rsp->sq_head = cpu_to_le16(req->sq->sqhd & 0x0000FFFF);
+}
+
+static void __nvmet_req_complete(struct nvmet_req *req, u16 status)
+{
+       if (!req->sq->sqhd_disabled)
+               nvmet_update_sq_head(req);
        req->rsp->sq_id = cpu_to_le16(req->sq->qid);
        req->rsp->command_id = req->cmd->common.command_id;
-
+       if (status)
+               nvmet_set_status(req, status);
        if (req->ns)
                nvmet_put_namespace(req->ns);
        req->ops->queue_response(req);
@@ -765,6 +767,7 @@ bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq,
        req->sg_cnt = 0;
        req->transfer_len = 0;
        req->rsp->status = 0;
+       req->rsp->sq_head = 0;
        req->ns = NULL;
 
        /* no support for fused commands yet */