[RFC PATCH v5 22/27] qedn: Add IO level qedn_send_req and fw_cq workqueue

Shai Malin
2021-05-19T12:37:53Z

This patch will present the IO level skeleton flows:

- qedn_send_req(): process new requests, similar to nvme_tcp_queue_rq().

- qedn_fw_cq_fp_wq(): process new FW completions, the flow starts from
the IRQ handler and for a single interrupt it will
process all the pending NVMeoF Completions under
polling mode.

Acked-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: Prabhakar Kushwaha <pkushwaha@marvell.com>
Signed-off-by: Omkar Kulkarni <okulkarni@marvell.com>
Signed-off-by: Michal Kalderon <mkalderon@marvell.com>
Signed-off-by: Ariel Elior <aelior@marvell.com>
Signed-off-by: Shai Malin <smalin@marvell.com>
---
drivers/nvme/hw/qedn/Makefile | 2 +-
drivers/nvme/hw/qedn/qedn.h | 13 +++++
drivers/nvme/hw/qedn/qedn_conn.c | 1 +
drivers/nvme/hw/qedn/qedn_main.c | 93 ++++++++++++++++++++++++++++---
drivers/nvme/hw/qedn/qedn_task.c | 95 ++++++++++++++++++++++++++++++++
5 files changed, 195 insertions(+), 9 deletions(-)
create mode 100644 drivers/nvme/hw/qedn/qedn_task.c

diff --git a/drivers/nvme/hw/qedn/Makefile b/drivers/nvme/hw/qedn/Makefile
index ece84772d317..888d466fa5ed 100644
--- a/drivers/nvme/hw/qedn/Makefile
+++ b/drivers/nvme/hw/qedn/Makefile
@@ -1,4 +1,4 @@
# SPDX-License-Identifier: GPL-2.0

obj-$(CONFIG_NVME_QEDN) += qedn.o
-qedn-y := qedn_main.o qedn_conn.o
+qedn-y := qedn_main.o qedn_conn.o qedn_task.o
\ No newline at end of file
diff --git a/drivers/nvme/hw/qedn/qedn.h b/drivers/nvme/hw/qedn/qedn.h
index 82261fa95f5d..18411c3a9596 100644
--- a/drivers/nvme/hw/qedn/qedn.h
+++ b/drivers/nvme/hw/qedn/qedn.h
@@ -47,6 +47,8 @@
#define QEDN_NON_ABORTIVE_TERMINATION 0
#define QEDN_ABORTIVE_TERMINATION 1

+#define QEDN_FW_CQ_FP_WQ_WORKQUEUE "qedn_fw_cq_fp_wq"
+
/*
* TCP offload stack default configurations and defines.
* Future enhancements will allow controlling the configurable
@@ -99,6 +101,7 @@ struct qedn_fp_queue {
struct qedn_ctx *qedn;
struct qed_sb_info *sb_info;
unsigned int cpu;
+ struct work_struct fw_cq_fp_wq_entry;
u16 sb_id;
char irqname[QEDN_IRQ_NAME_LEN];
};
@@ -127,6 +130,7 @@ struct qedn_ctx {
struct qedn_fp_queue *fp_q_arr;
struct nvmetcp_glbl_queue_entry *fw_cq_array_virt;
dma_addr_t fw_cq_array_phy; /* Physical address of fw_cq_array_virt */
+ struct workqueue_struct *fw_cq_fp_wq;
};

struct qedn_endpoint {
@@ -210,6 +214,11 @@ struct qedn_ctrl {

/* Connection level struct */
struct qedn_conn_ctx {
+ /* IO path */
+ struct qedn_fp_queue *fp_q;
+ unsigned int cpu;
+ int qid;
+
struct qedn_ctx *qedn;
struct nvme_tcp_ofld_queue *queue;
struct nvme_tcp_ofld_ctrl *ctrl;
@@ -268,5 +277,9 @@ int qedn_wait_for_conn_est(struct qedn_conn_ctx *conn_ctx);
int qedn_set_con_state(struct qedn_conn_ctx *conn_ctx, enum qedn_conn_state new_state);
void qedn_terminate_connection(struct qedn_conn_ctx *conn_ctx);
__be16 qedn_get_in_port(struct sockaddr_storage *sa);
+inline int qedn_validate_cccid_in_range(struct qedn_conn_ctx *conn_ctx, u16 cccid);
+void qedn_queue_request(struct qedn_conn_ctx *qedn_conn, struct nvme_tcp_ofld_req *req);
+void qedn_nvme_req_fp_wq_handler(struct work_struct *work);
+void qedn_io_work_cq(struct qedn_ctx *qedn, struct nvmetcp_fw_cqe *cqe);

#endif /* _QEDN_H_ */
diff --git a/drivers/nvme/hw/qedn/qedn_conn.c b/drivers/nvme/hw/qedn/qedn_conn.c
index ad90b09f9a67..a66f77b823b0 100644
--- a/drivers/nvme/hw/qedn/qedn_conn.c
+++ b/drivers/nvme/hw/qedn/qedn_conn.c
@@ -404,6 +404,7 @@ static int qedn_prep_and_offload_queue(struct qedn_conn_ctx *conn_ctx)
}

set_bit(QEDN_CONN_RESRC_FW_SQ, &conn_ctx->resrc_state);
+
rc = qed_ops->acquire_conn(qedn->cdev,
&conn_ctx->conn_handle,
&conn_ctx->fw_cid,
diff --git a/drivers/nvme/hw/qedn/qedn_main.c b/drivers/nvme/hw/qedn/qedn_main.c
index 85126f488f9b..22f602349773 100644
--- a/drivers/nvme/hw/qedn/qedn_main.c
+++ b/drivers/nvme/hw/qedn/qedn_main.c
@@ -243,6 +243,18 @@ static int qedn_release_ctrl(struct nvme_tcp_ofld_ctrl *ctrl)
return 0;
}

+static void qedn_set_ctrl_io_cpus(struct qedn_conn_ctx *conn_ctx, int qid)
+{
+ struct qedn_ctx *qedn = conn_ctx->qedn;
+ struct qedn_fp_queue *fp_q = NULL;
+ int index;
+
+ index = qid ? (qid - 1) % qedn->num_fw_cqs : 0;
+ fp_q = &qedn->fp_q_arr[index];
+
+ conn_ctx->cpu = fp_q->cpu;
+}
+
static int qedn_create_queue(struct nvme_tcp_ofld_queue *queue, int qid, size_t q_size)
{
struct nvme_tcp_ofld_ctrl *ctrl = queue->ctrl;
@@ -264,6 +276,7 @@ static int qedn_create_queue(struct nvme_tcp_ofld_queue *queue, int qid, size_t
conn_ctx->queue = queue;
conn_ctx->ctrl = ctrl;
conn_ctx->sq_depth = q_size;
+ qedn_set_ctrl_io_cpus(conn_ctx, qid);

init_waitqueue_head(&conn_ctx->conn_waitq);
atomic_set(&conn_ctx->est_conn_indicator, 0);
@@ -271,6 +284,8 @@ static int qedn_create_queue(struct nvme_tcp_ofld_queue *queue, int qid, size_t

spin_lock_init(&conn_ctx->conn_state_lock);

+ conn_ctx->qid = qid;
+
qedn_initialize_endpoint(&conn_ctx->ep, qedn->local_mac_addr,
&ctrl->conn_params);

@@ -361,14 +376,18 @@ static int qedn_init_req(struct nvme_tcp_ofld_req *req)

static void qedn_commit_rqs(struct nvme_tcp_ofld_queue *queue)
{
- /* Placeholder - queue work */
+ /* Do nothing */
}

static int qedn_send_req(struct nvme_tcp_ofld_req *req)
{
- /* Placeholder - qedn_send_req */
+ struct qedn_conn_ctx *qedn_conn = (struct qedn_conn_ctx *)req->queue->private_data;

- return 0;
+ /* Under the assumption that the cccid/tag will be in the range of 0 to sq_depth-1. */
+ if (!req->async && qedn_validate_cccid_in_range(qedn_conn, req->rq->tag))
+ return BLK_STS_NOTSUPP;
+
+ return qedn_queue_request(qedn_conn, req);
}

static struct nvme_tcp_ofld_ops qedn_ofld_ops = {
@@ -410,9 +429,59 @@ struct qedn_conn_ctx *qedn_get_conn_hash(struct qedn_ctx *qedn, u16 icid)
}

/* Fastpath IRQ handler */
+void qedn_fw_cq_fp_handler(struct qedn_fp_queue *fp_q)
+{
+ u16 sb_id, cq_prod_idx, cq_cons_idx;
+ struct qedn_ctx *qedn = fp_q->qedn;
+ struct nvmetcp_fw_cqe *cqe = NULL;
+
+ sb_id = fp_q->sb_id;
+ qed_sb_update_sb_idx(fp_q->sb_info);
+
+ /* rmb - to prevent missing new cqes */
+ rmb();
+
+ /* Read the latest cq_prod from the SB */
+ cq_prod_idx = *fp_q->cq_prod;
+ cq_cons_idx = qed_chain_get_cons_idx(&fp_q->cq_chain);
+
+ while (cq_cons_idx != cq_prod_idx) {
+ cqe = qed_chain_consume(&fp_q->cq_chain);
+ if (likely(cqe))
+ qedn_io_work_cq(qedn, cqe);
+ else
+ pr_err("Failed consuming cqe\n");
+
+ cq_cons_idx = qed_chain_get_cons_idx(&fp_q->cq_chain);
+
+ /* Check if new completions were posted */
+ if (unlikely(cq_prod_idx == cq_cons_idx)) {
+ /* rmb - to prevent missing new cqes */
+ rmb();
+
+ /* Update the latest cq_prod from the SB */
+ cq_prod_idx = *fp_q->cq_prod;
+ }
+ }
+}
+
+static void qedn_fw_cq_fq_wq_handler(struct work_struct *work)
+{
+ struct qedn_fp_queue *fp_q = container_of(work, struct qedn_fp_queue, fw_cq_fp_wq_entry);
+
+ qedn_fw_cq_fp_handler(fp_q);
+ qed_sb_ack(fp_q->sb_info, IGU_INT_ENABLE, 1);
+}
+
static irqreturn_t qedn_irq_handler(int irq, void *dev_id)
{
- /* Placeholder */
+ struct qedn_fp_queue *fp_q = dev_id;
+ struct qedn_ctx *qedn = fp_q->qedn;
+
+ fp_q->cpu = smp_processor_id();
+
+ qed_sb_ack(fp_q->sb_info, IGU_INT_DISABLE, 0);
+ queue_work_on(fp_q->cpu, qedn->fw_cq_fp_wq, &fp_q->fw_cq_fp_wq_entry);

return IRQ_HANDLED;
}
@@ -546,6 +615,8 @@ static void qedn_free_function_queues(struct qedn_ctx *qedn)
int i;

/* Free workqueues */
+ destroy_workqueue(qedn->fw_cq_fp_wq);
+ qedn->fw_cq_fp_wq = NULL;

/* Free the fast path queues*/
for (i = 0; i < qedn->num_fw_cqs; i++) {
@@ -613,7 +684,14 @@ static int qedn_alloc_function_queues(struct qedn_ctx *qedn)
u64 cq_phy_addr;
int i;

- /* Place holder - IO-path workqueues */
+ qedn->fw_cq_fp_wq = alloc_workqueue(QEDN_FW_CQ_FP_WQ_WORKQUEUE,
+ WQ_HIGHPRI | WQ_MEM_RECLAIM, 0);
+ if (!qedn->fw_cq_fp_wq) {
+ rc = -ENODEV;
+ pr_err("Unable to create fastpath FW CQ workqueue!\n");
+
+ return rc;
+ }

qedn->fp_q_arr = kcalloc(qedn->num_fw_cqs,
sizeof(struct qedn_fp_queue), GFP_KERNEL);
@@ -641,7 +719,7 @@ static int qedn_alloc_function_queues(struct qedn_ctx *qedn)
chain_params.mode = QED_CHAIN_MODE_PBL,
chain_params.cnt_type = QED_CHAIN_CNT_TYPE_U16,
chain_params.num_elems = QEDN_FW_CQ_SIZE;
- chain_params.elem_size = 64; /*Placeholder - sizeof(struct nvmetcp_fw_cqe)*/
+ chain_params.elem_size = sizeof(struct nvmetcp_fw_cqe);

rc = qed_ops->common->chain_alloc(qedn->cdev,
&fp_q->cq_chain,
@@ -670,8 +748,7 @@ static int qedn_alloc_function_queues(struct qedn_ctx *qedn)
sb = fp_q->sb_info->sb_virt;
fp_q->cq_prod = (u16 *)&sb->pi_array[QEDN_PROTO_CQ_PROD_IDX];
fp_q->qedn = qedn;
-
- /* Placeholder - Init IO-path workqueue */
+ INIT_WORK(&fp_q->fw_cq_fp_wq_entry, qedn_fw_cq_fq_wq_handler);

/* Placeholder - Init IO-path resources */
}
diff --git a/drivers/nvme/hw/qedn/qedn_task.c b/drivers/nvme/hw/qedn/qedn_task.c
new file mode 100644
index 000000000000..56f0af855f6e
--- /dev/null
+++ b/drivers/nvme/hw/qedn/qedn_task.c
@@ -0,0 +1,95 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2021 Marvell. All rights reserved.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+ /* Kernel includes */
+#include <linux/kernel.h>
+
+/* Driver includes */
+#include "qedn.h"
+
+inline int qedn_validate_cccid_in_range(struct qedn_conn_ctx *conn_ctx, u16 cccid)
+{
+ int rc = 0;
+
+ if (unlikely(cccid >= conn_ctx->sq_depth)) {
+ pr_err("cccid 0x%x out of range ( > sq depth)\n", cccid);
+ rc = -EINVAL;
+ }
+
+ return rc;
+}
+
+static bool qedn_process_req(struct qedn_conn_ctx *qedn_conn)
+{
+ return true;
+}
+
+void qedn_queue_request(struct qedn_conn_ctx *qedn_conn, struct nvme_tcp_ofld_req *req)
+{
+ bool empty, res = false;
+
+ res = qedn_process_req(qedn_conn);
+}
+
+struct qedn_task_ctx *qedn_cqe_get_active_task(struct nvmetcp_fw_cqe *cqe)
+{
+ struct regpair *p = &cqe->task_opaque;
+
+ return (struct qedn_task_ctx *)((((u64)(le32_to_cpu(p->hi)) << 32)
+ + le32_to_cpu(p->lo)));
+}
+
+void qedn_io_work_cq(struct qedn_ctx *qedn, struct nvmetcp_fw_cqe *cqe)
+{
+ struct qedn_task_ctx *qedn_task = NULL;
+ struct qedn_conn_ctx *conn_ctx = NULL;
+ u16 itid;
+ u32 cid;
+
+ conn_ctx = qedn_get_conn_hash(qedn, le16_to_cpu(cqe->conn_id));
+ if (unlikely(!conn_ctx)) {
+ pr_err("CID 0x%x: Failed to fetch conn_ctx from hash\n",
+ le16_to_cpu(cqe->conn_id));
+
+ return;
+ }
+
+ cid = conn_ctx->fw_cid;
+ itid = le16_to_cpu(cqe->itid);
+ qedn_task = qedn_cqe_get_active_task(cqe);
+ if (unlikely(!qedn_task))
+ return;
+
+ if (likely(cqe->cqe_type == NVMETCP_FW_CQE_TYPE_NORMAL)) {
+ /* Placeholder - verify the connection was established */
+
+ switch (cqe->task_type) {
+ case NVMETCP_TASK_TYPE_HOST_WRITE:
+ case NVMETCP_TASK_TYPE_HOST_READ:
+
+ /* Placeholder - IO flow */
+
+ break;
+
+ case NVMETCP_TASK_TYPE_HOST_READ_NO_CQE:
+
+ /* Placeholder - IO flow */
+
+ break;
+
+ case NVMETCP_TASK_TYPE_INIT_CONN_REQUEST:
+
+ /* Placeholder - ICReq flow */
+
+ break;
+ default:
+ pr_info("Could not identify task type\n");
+ }
+ } else {
+ /* Placeholder - Recovery flows */
+ }
+}