nvme-tcp: support separate queue maps for read and write

Allow NVMF_OPT_NR_WRITE_QUEUES to describe additional write queues.  In
addition, implement .map_queues that will apply 2 queue maps for read
and write queue sets.

Note that with the separate queue map, HCTX_TYPE_READ will always use
nr_io_queues and HCTX_TYPE_DEFAULT will use nr_write_queues.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
index 15543358e245603c753174e847f19787f89bf3ca..51826479a41e6dbf4dc7e032261fb49a97cd8562 100644 (file)
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -1215,7 +1215,7 @@ static int nvme_tcp_alloc_queue(struct nvme_ctrl *nctrl,
        struct nvme_tcp_ctrl *ctrl = to_tcp_ctrl(nctrl);
        struct nvme_tcp_queue *queue = &ctrl->queues[qid];
        struct linger sol = { .l_onoff = 1, .l_linger = 0 };
-       int ret, opt, rcv_pdu_size;
+       int ret, opt, rcv_pdu_size, n;
 
        queue->ctrl = ctrl;
        INIT_LIST_HEAD(&queue->send_list);
@@ -1271,7 +1271,11 @@ static int nvme_tcp_alloc_queue(struct nvme_ctrl *nctrl,
        }
 
        queue->sock->sk->sk_allocation = GFP_ATOMIC;
-       queue->io_cpu = (qid == 0) ? 0 : qid - 1;
+       if (!qid)
+               n = 0;
+       else
+               n = (qid - 1) % num_online_cpus();
+       queue->io_cpu = cpumask_next_wrap(n - 1, cpu_online_mask, -1, false);
        queue->request = NULL;
        queue->data_remaining = 0;
        queue->ddgst_remaining = 0;
@@ -1433,6 +1437,7 @@ static struct blk_mq_tag_set *nvme_tcp_alloc_tagset(struct nvme_ctrl *nctrl,
                set->driver_data = ctrl;
                set->nr_hw_queues = nctrl->queue_count - 1;
                set->timeout = NVME_IO_TIMEOUT;
+               set->nr_maps = 2 /* default + read */;
        }
 
        ret = blk_mq_alloc_tag_set(set);
@@ -1527,7 +1532,12 @@ out_free_queues:
 
 static unsigned int nvme_tcp_nr_io_queues(struct nvme_ctrl *ctrl)
 {
-       return min(ctrl->queue_count - 1, num_online_cpus());
+       unsigned int nr_io_queues;
+
+       nr_io_queues = min(ctrl->opts->nr_io_queues, num_online_cpus());
+       nr_io_queues += min(ctrl->opts->nr_write_queues, num_online_cpus());
+
+       return nr_io_queues;
 }
 
 static int nvme_alloc_io_queues(struct nvme_ctrl *ctrl)
@@ -2052,6 +2062,29 @@ static blk_status_t nvme_tcp_queue_rq(struct blk_mq_hw_ctx *hctx,
        return BLK_STS_OK;
 }
 
+static int nvme_tcp_map_queues(struct blk_mq_tag_set *set)
+{
+       struct nvme_tcp_ctrl *ctrl = set->driver_data;
+
+       set->map[HCTX_TYPE_DEFAULT].queue_offset = 0;
+       set->map[HCTX_TYPE_READ].nr_queues = ctrl->ctrl.opts->nr_io_queues;
+       if (ctrl->ctrl.opts->nr_write_queues) {
+               /* separate read/write queues */
+               set->map[HCTX_TYPE_DEFAULT].nr_queues =
+                               ctrl->ctrl.opts->nr_write_queues;
+               set->map[HCTX_TYPE_READ].queue_offset =
+                               ctrl->ctrl.opts->nr_write_queues;
+       } else {
+               /* mixed read/write queues */
+               set->map[HCTX_TYPE_DEFAULT].nr_queues =
+                               ctrl->ctrl.opts->nr_io_queues;
+               set->map[HCTX_TYPE_READ].queue_offset = 0;
+       }
+       blk_mq_map_queues(&set->map[HCTX_TYPE_DEFAULT]);
+       blk_mq_map_queues(&set->map[HCTX_TYPE_READ]);
+       return 0;
+}
+
 static struct blk_mq_ops nvme_tcp_mq_ops = {
        .queue_rq       = nvme_tcp_queue_rq,
        .complete       = nvme_complete_rq,
@@ -2059,6 +2092,7 @@ static struct blk_mq_ops nvme_tcp_mq_ops = {
        .exit_request   = nvme_tcp_exit_request,
        .init_hctx      = nvme_tcp_init_hctx,
        .timeout        = nvme_tcp_timeout,
+       .map_queues     = nvme_tcp_map_queues,
 };
 
 static struct blk_mq_ops nvme_tcp_admin_mq_ops = {
@@ -2113,7 +2147,7 @@ static struct nvme_ctrl *nvme_tcp_create_ctrl(struct device *dev,
 
        INIT_LIST_HEAD(&ctrl->list);
        ctrl->ctrl.opts = opts;
-       ctrl->ctrl.queue_count = opts->nr_io_queues + 1; /* +1 for admin queue */
+       ctrl->ctrl.queue_count = opts->nr_io_queues + opts->nr_write_queues + 1;
        ctrl->ctrl.sqsize = opts->queue_size - 1;
        ctrl->ctrl.kato = opts->kato;
 
@@ -2155,7 +2189,7 @@ static struct nvme_ctrl *nvme_tcp_create_ctrl(struct device *dev,
                goto out_free_ctrl;
        }
 
-       ctrl->queues = kcalloc(opts->nr_io_queues + 1, sizeof(*ctrl->queues),
+       ctrl->queues = kcalloc(ctrl->ctrl.queue_count, sizeof(*ctrl->queues),
                                GFP_KERNEL);
        if (!ctrl->queues) {
                ret = -ENOMEM;
@@ -2206,7 +2240,8 @@ static struct nvmf_transport_ops nvme_tcp_transport = {
        .required_opts  = NVMF_OPT_TRADDR,
        .allowed_opts   = NVMF_OPT_TRSVCID | NVMF_OPT_RECONNECT_DELAY |
                          NVMF_OPT_HOST_TRADDR | NVMF_OPT_CTRL_LOSS_TMO |
-                         NVMF_OPT_HDR_DIGEST | NVMF_OPT_DATA_DIGEST,
+                         NVMF_OPT_HDR_DIGEST | NVMF_OPT_DATA_DIGEST |
+                         NVMF_OPT_NR_WRITE_QUEUES,
        .create_ctrl    = nvme_tcp_create_ctrl,
 };