From: James Smart <jsmart2021@gmail.com>

Date: Tue, 31 Mar 2020 09:50:01 -0700

Subject: [PATCH] nvme-fcloop: add target to host LS request support

Git-commit: 6cefacbb8f87287de7450d9d0d6c764b809e576b

Git-repo: git://git.infradead.org/nvme.git

Patch-mainline: Queued in subsystem maintainer repository

References: bsc#1169045

Add support for performing LS requests from target to host.

Include sending request from targetport, reception into host,

host sending ls rsp.

Signed-off-by: James Smart <jsmart2021@gmail.com>

Reviewed-by: Hannes Reinecke <hare@suse.de>

Signed-off-by: Christoph Hellwig <hch@lst.de>

Acked-by: Hannes Reinecke <hare@suse.com>

---

 drivers/nvme/target/fcloop.c | 130 +++++++++++++++++++++++++++++++++++++++----

 1 file changed, 118 insertions(+), 12 deletions(-)

diff --git a/drivers/nvme/target/fcloop.c b/drivers/nvme/target/fcloop.c

index fac7dbe572db..2ff1d1334a03 100644

--- a/drivers/nvme/target/fcloop.c

+++ b/drivers/nvme/target/fcloop.c

@@ -208,10 +208,13 @@ struct fcloop_rport {

 };

 struct fcloop_tport {

-	struct nvmet_fc_target_port *targetport;

-	struct nvme_fc_remote_port *remoteport;

-	struct fcloop_nport *nport;

-	struct fcloop_lport *lport;

+	struct nvmet_fc_target_port	*targetport;

+	struct nvme_fc_remote_port	*remoteport;

+	struct fcloop_nport		*nport;

+	struct fcloop_lport		*lport;

+	spinlock_t			lock;

+	struct list_head		ls_list;

+	struct work_struct		ls_work;

 };

 struct fcloop_nport {

@@ -226,11 +229,6 @@ struct fcloop_nport {

 	u32 port_id;

 };

-enum {

-	H2T	= 0,

-	T2H	= 1,

-};

-

 struct fcloop_lsreq {

 	struct nvmefc_ls_req		*lsreq;

 	struct nvmefc_ls_rsp		ls_rsp;

@@ -337,7 +335,6 @@ fcloop_h2t_ls_req(struct nvme_fc_local_port *localport,

 	struct fcloop_rport *rport = remoteport->private;

 	int ret = 0;

-	tls_req->lsdir = H2T;

 	tls_req->lsreq = lsreq;

 	INIT_LIST_HEAD(&tls_req->ls_list);

@@ -351,8 +348,9 @@ fcloop_h2t_ls_req(struct nvme_fc_local_port *localport,

 	}

 	tls_req->status = 0;

-	ret = nvmet_fc_rcv_ls_req(rport->targetport, NULL, &tls_req->ls_rsp,

-				 lsreq->rqstaddr, lsreq->rqstlen);

+	ret = nvmet_fc_rcv_ls_req(rport->targetport, rport,

+				  &tls_req->ls_rsp,

+				  lsreq->rqstaddr, lsreq->rqstlen);

 	return ret;

 }

@@ -384,6 +382,99 @@ fcloop_h2t_xmt_ls_rsp(struct nvmet_fc_target_port *targetport,

 	return 0;

 }

+static void

+fcloop_tport_lsrqst_work(struct work_struct *work)

+{

+	struct fcloop_tport *tport =

+		container_of(work, struct fcloop_tport, ls_work);

+	struct fcloop_lsreq *tls_req;

+

+	spin_lock(&tport->lock);

+	for (;;) {

+		tls_req = list_first_entry_or_null(&tport->ls_list,

+				struct fcloop_lsreq, ls_list);

+		if (!tls_req)

+			break;

+

+		list_del(&tls_req->ls_list);

+		spin_unlock(&tport->lock);

+

+		tls_req->lsreq->done(tls_req->lsreq, tls_req->status);

+		/*

+		 * callee may free memory containing tls_req.

+		 * do not reference lsreq after this.

+		 */

+

+		spin_lock(&tport->lock);

+	}

+	spin_unlock(&tport->lock);

+}

+

+static int

+fcloop_t2h_ls_req(struct nvmet_fc_target_port *targetport, void *hosthandle,

+			struct nvmefc_ls_req *lsreq)

+{

+	struct fcloop_lsreq *tls_req = lsreq->private;

+	struct fcloop_tport *tport = targetport->private;

+	int ret = 0;

+

+	/*

+	 * hosthandle should be the dst.rport value.

+	 * hosthandle ignored as fcloop currently is

+	 * 1:1 tgtport vs remoteport

+	 */

+	tls_req->lsreq = lsreq;

+	INIT_LIST_HEAD(&tls_req->ls_list);

+

+	if (!tport->remoteport) {

+		tls_req->status = -ECONNREFUSED;

+		spin_lock(&tport->lock);

+		list_add_tail(&tport->ls_list, &tls_req->ls_list);

+		spin_unlock(&tport->lock);

+		schedule_work(&tport->ls_work);

+		return ret;

+	}

+

+	tls_req->status = 0;

+	ret = nvme_fc_rcv_ls_req(tport->remoteport, &tls_req->ls_rsp,

+				 lsreq->rqstaddr, lsreq->rqstlen);

+

+	return ret;

+}

+

+static int

+fcloop_t2h_xmt_ls_rsp(struct nvme_fc_local_port *localport,

+			struct nvme_fc_remote_port *remoteport,

+			struct nvmefc_ls_rsp *lsrsp)

+{

+	struct fcloop_lsreq *tls_req = ls_rsp_to_lsreq(lsrsp);

+	struct nvmefc_ls_req *lsreq = tls_req->lsreq;

+	struct fcloop_rport *rport = remoteport->private;

+	struct nvmet_fc_target_port *targetport = rport->targetport;

+	struct fcloop_tport *tport;

+

+	memcpy(lsreq->rspaddr, lsrsp->rspbuf,

+		((lsreq->rsplen < lsrsp->rsplen) ?

+				lsreq->rsplen : lsrsp->rsplen));

+	lsrsp->done(lsrsp);

+

+	if (targetport) {

+		tport = targetport->private;

+		spin_lock(&tport->lock);

+		list_add_tail(&tport->ls_list, &tls_req->ls_list);

+		spin_unlock(&tport->lock);

+		schedule_work(&tport->ls_work);

+	}

+

+	return 0;

+}

+

+static void

+fcloop_t2h_host_release(void *hosthandle)

+{

+	/* host handle ignored for now */

+}

+

 /*

  * Simulate reception of RSCN and converting it to a initiator transport

  * call to rescan a remote port.

@@ -775,6 +866,12 @@ fcloop_h2t_ls_abort(struct nvme_fc_local_port *localport,

 {

 }

+static void

+fcloop_t2h_ls_abort(struct nvmet_fc_target_port *targetport,

+			void *hosthandle, struct nvmefc_ls_req *lsreq)

+{

+}

+

 static void

 fcloop_fcp_abort(struct nvme_fc_local_port *localport,

 			struct nvme_fc_remote_port *remoteport,

@@ -874,6 +971,7 @@ fcloop_targetport_delete(struct nvmet_fc_target_port *targetport)

 {

 	struct fcloop_tport *tport = targetport->private;

+	flush_work(&tport->ls_work);

 	fcloop_nport_put(tport->nport);

 }

@@ -890,6 +988,7 @@ static struct nvme_fc_port_template fctemplate = {

 	.fcp_io			= fcloop_fcp_req,

 	.ls_abort		= fcloop_h2t_ls_abort,

 	.fcp_abort		= fcloop_fcp_abort,

+	.xmt_ls_rsp		= fcloop_t2h_xmt_ls_rsp,

 	.max_hw_queues		= FCLOOP_HW_QUEUES,

 	.max_sgl_segments	= FCLOOP_SGL_SEGS,

 	.max_dif_sgl_segments	= FCLOOP_SGL_SEGS,

@@ -908,6 +1007,9 @@ static struct nvmet_fc_target_template tgttemplate = {

 	.fcp_abort		= fcloop_tgt_fcp_abort,

 	.fcp_req_release	= fcloop_fcp_req_release,

 	.discovery_event	= fcloop_tgt_discovery_evt,

+	.ls_req			= fcloop_t2h_ls_req,

+	.ls_abort		= fcloop_t2h_ls_abort,

+	.host_release		= fcloop_t2h_host_release,

 	.max_hw_queues		= FCLOOP_HW_QUEUES,

 	.max_sgl_segments	= FCLOOP_SGL_SEGS,

 	.max_dif_sgl_segments	= FCLOOP_SGL_SEGS,

@@ -916,6 +1018,7 @@ static struct nvmet_fc_target_template tgttemplate = {

 	.target_features	= 0,

 	/* sizes of additional private data for data structures */

 	.target_priv_sz		= sizeof(struct fcloop_tport),

+	.lsrqst_priv_sz		= sizeof(struct fcloop_lsreq),

 };

 static ssize_t

@@ -1265,6 +1368,9 @@ fcloop_create_target_port(struct device *dev, struct device_attribute *attr,

 	tport->nport = nport;

 	tport->lport = nport->lport;

 	nport->tport = tport;

+	spin_lock_init(&tport->lock);

+	INIT_WORK(&tport->ls_work, fcloop_tport_lsrqst_work);

+	INIT_LIST_HEAD(&tport->ls_list);

 	return count;

 }

-- 

2.16.4