diff mbox

[5/5] nvme-fabrics: Add FC LLDD loopback driver to test FC host and target transport

Message ID 5792b91f.Lb5BdNQrSWnmgOYG%james.smart@broadcom.com (mailing list archive)
State Not Applicable, archived
Headers show

Commit Message

James Smart July 23, 2016, 12:23 a.m. UTC
Add FC LLDD loopback driver to test FC host and target transport within
nvme-fabrics

To aid in the development and testing of the lower-level api of the FC
transport, this loopback driver has been created to act as if it were a
FC hba driver supporting both the host interfaces as well as the target
interfaces with the nvme FC transport.


Signed-off-by: James Smart <james.smart@broadcom.com>

---
 drivers/nvme/target/Kconfig  |  13 +
 drivers/nvme/target/Makefile |   2 +
 drivers/nvme/target/fcloop.c | 803 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 818 insertions(+)
 create mode 100644 drivers/nvme/target/fcloop.c

Comments

james_p_freyensee@linux.intel.com Aug. 3, 2016, 12:15 a.m. UTC | #1
On Fri, 2016-07-22 at 17:23 -0700, James Smart wrote:

A couple comments.

> Add FC LLDD loopback driver to test FC host and target transport
> within
> nvme-fabrics
> 
> To aid in the development and testing of the lower-level api of the
> FC
> transport, this loopback driver has been created to act as if it were
> a
> FC hba driver supporting both the host interfaces as well as the
> target
> interfaces with the nvme FC transport.
> 
> 
> Signed-off-by: James Smart <james.smart@broadcom.com>
> 
> ---

snip...

>  +int
> +fcloop_fcp_op(struct nvmet_fc_target_port *tgtport,
> +			struct nvmefc_tgt_fcp_req *tgt_fcpreq)
> +{
> +	struct fcloop_fcpreq *tfcp_req =
> +		container_of(tgt_fcpreq, struct fcloop_fcpreq,
> tgt_fcp_req);
> +	struct nvmefc_fcp_req *fcpreq = tfcp_req->fcpreq;
> +	u32 rsplen = 0, xfrlen = 0;
> +	int fcp_err = 0;
> +	u8 op = tgt_fcpreq->op;
> +
> +	switch (op) {
> +	case NVMET_FCOP_WRITEDATA:
> +		xfrlen = tgt_fcpreq->transfer_length;
> +		fcloop_fcp_copy_data(op, tgt_fcpreq->sg, fcpreq
> ->first_sgl,
> +					tgt_fcpreq->offset, xfrlen);
> +		fcpreq->transferred_length += xfrlen;
> +		break;
> +
> +	case NVMET_FCOP_READDATA:
> +	case NVMET_FCOP_READDATA_RSP:
> +		xfrlen = tgt_fcpreq->transfer_length;
> +		fcloop_fcp_copy_data(op, tgt_fcpreq->sg, fcpreq
> ->first_sgl,
> +					tgt_fcpreq->offset, xfrlen);
> +		fcpreq->transferred_length += xfrlen;
> +		if (op == NVMET_FCOP_READDATA)
> +			break;
> +
> +		/* Fall-Thru to RSP handling */
> +
> +	case NVMET_FCOP_RSP:
> +		rsplen = ((fcpreq->rsplen < tgt_fcpreq->rsplen) ?
> +				fcpreq->rsplen : tgt_fcpreq
> ->rsplen);
> +		memcpy(fcpreq->rspaddr, tgt_fcpreq->rspaddr,
> rsplen);
> +		if (rsplen < tgt_fcpreq->rsplen)
> +			fcp_err = -E2BIG;
> +		fcpreq->rcv_rsplen = rsplen;
> +		fcpreq->status = 0;
> +		tfcp_req->status = 0;
> +		break;
> +
> +	case NVMET_FCOP_ABORT:
> +		tfcp_req->status = NVME_SC_FC_TRANSPORT_ABORTED;
> +		break;
> +
> +	default:
> +		fcp_err = -EINVAL;
> +		break;
> +	}
> +
> +	tgt_fcpreq->transferred_length = xfrlen;
> +	tgt_fcpreq->fcp_error = fcp_err;
> +	tgt_fcpreq->done(tgt_fcpreq);
> +
> +	if ((!fcp_err) && (op == NVMET_FCOP_RSP ||
> +			op == NVMET_FCOP_READDATA_RSP ||
> +			op == NVMET_FCOP_ABORT))
> +		schedule_work(&tfcp_req->work);
> +
> +	return 0;

if this function returns an 'int', why would it always return 0 and not
the fcp_err values (if there is an error)?

> +}
> +
> +void
> +fcloop_ls_abort(struct nvme_fc_local_port *localport,
> +			struct nvme_fc_remote_port *remoteport,
> +				struct nvmefc_ls_req *lsreq)
> +{
> +}
> +
> +void
> +fcloop_fcp_abort(struct nvme_fc_local_port *localport,
> +			struct nvme_fc_remote_port *remoteport,
> +			void *hw_queue_handle,
> +			struct nvmefc_fcp_req *fcpreq)
> +{
> +}
> +
> +
> +struct nvme_fc_port_template fctemplate = {
> +	.create_queue	= fcloop_create_queue,
> +	.delete_queue	= fcloop_delete_queue,
> +	.ls_req		= fcloop_ls_req,
> +	.fcp_io		= fcloop_fcp_req,
> +	.ls_abort	= fcloop_ls_abort,
> +	.fcp_abort	= fcloop_fcp_abort,
> +
> +	.max_hw_queues	= 1,
> +	.max_sgl_segments = 256,
> +	.max_dif_sgl_segments = 256,
> +	.dma_boundary = 0xFFFFFFFF,

Between here and "struct nvmet_fc_target_template tgttemplate" they are
assigning the same magic values to the same variable names, so why not
have these values as #defines for a tad easier maintainability?

> +	/* sizes of additional private data for data structures */
> +	.local_priv_sz	= sizeof(struct fcloop_lport),
> +	.remote_priv_sz	= sizeof(struct fcloop_rport),
> +	.lsrqst_priv_sz = sizeof(struct fcloop_lsreq),
> +	.fcprqst_priv_sz = sizeof(struct fcloop_fcpreq),
> +};
> +
> +struct nvmet_fc_target_template tgttemplate = {
> +	.xmt_ls_rsp	= fcloop_xmt_ls_rsp,
> +	.fcp_op		= fcloop_fcp_op,
> +
> +	.max_hw_queues	= 1,
> +	.max_sgl_segments = 256,
> +	.max_dif_sgl_segments = 256,
> +	.dma_boundary = 0xFFFFFFFF,
> +

see above comment.

> +	/* optional features */
> +	.target_features = NVMET_FCTGTFEAT_READDATA_RSP,
> +
> +	/* sizes of additional private data for data structures */
> +	.target_priv_sz = sizeof(struct fcloop_tgtport),
> +};
> +
> +static ssize_t
> +fcloop_create_local_port(struct device *dev, struct device_attribute
> *attr,
> +		const char *buf, size_t count)
> +{
> +	struct nvme_fc_port_info pinfo;
> +	struct fcloop_ctrl_options *opts;
> +	struct nvme_fc_local_port *localport;
> +	struct fcloop_lport *lport;
> +	int ret;
> +
> +	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
> +	if (!opts)
> +		return -ENOMEM;
> +
> +	ret = fcloop_parse_options(opts, buf);
> +	if (ret)
> +		goto out_free_opts;
> +
> +	/* everything there ? */
> +	if ((opts->mask & LPORT_OPTS) != LPORT_OPTS) {
> +		ret = -EINVAL;
> +		goto out_free_opts;
> +	}
> +
> +	pinfo.fabric_name = opts->fabric;
> +	pinfo.node_name = opts->wwnn;
> +	pinfo.port_name = opts->wwpn;
> +	pinfo.port_role = opts->roles;
> +	pinfo.port_id = opts->fcaddr;
> +
> +	ret = nvme_fc_register_localport(&pinfo, &fctemplate, NULL,
> &localport);
> +	if (!ret) {
> +		/* success */
> +		lport = localport->private;
> +		lport->localport = localport;
> +		INIT_LIST_HEAD(&lport->list);
> +		INIT_LIST_HEAD(&lport->rport_list);
> +		list_add_tail(&lport->list, &fcloop_lports);
> +
> +		/* mark all of the input buffer consumed */
> +		ret = count;
> +	}
> +
> +out_free_opts:
> +	kfree(opts);
> +	return ret;
> +}
> +
> +static int __delete_local_port(struct fcloop_lport *lport)
> +{
> +	int ret;
> +
> +	if (!list_empty(&lport->rport_list))
> +		return -EBUSY;
> +
> +	list_del(&lport->list);
> +

Is a mutex or locking mechanism not needed here for this list?

> +	ret = nvme_fc_unregister_localport(lport->localport);
> +
> +	return ret;
> +}
> +
> +static ssize_t
> +fcloop_delete_local_port(struct device *dev, struct device_attribute
> *attr,
> +		const char *buf, size_t count)
> +{
> +	struct fcloop_lport *lport, *lnext;
> +	u64 fabric, portname;
> +	int ret;
> +
> +	ret = fcloop_parse_nm_options(dev, &fabric, &portname, buf);
> +	if (ret)
> +		return ret;
> +
> +	list_for_each_entry_safe(lport, lnext, &fcloop_lports, list)
> {
> +		if ((lport->localport->fabric_name == fabric) &&
> +		    (lport->localport->port_name == portname)) {
> +			break;
> +		}
> +	}
> +	if (is_end_of_list(lport, &fcloop_lports, list))
> +		return -ENOENT;
> +
> +	ret = __delete_local_port(lport);
> +
> +	if (!ret)
> +		return count;
> +
> +	return ret;
> +}
> +
> +static ssize_t
> +fcloop_create_remote_port(struct device *dev, struct
> device_attribute *attr,
> +		const char *buf, size_t count)
> +{
> +	struct fcloop_ctrl_options *opts;
> +	struct fcloop_lport *lport, *lnext;
> +	struct nvme_fc_remote_port *remoteport;
> +	struct fcloop_rport *rport;
> +	struct nvme_fc_port_info pinfo;
> +	struct nvmet_fc_port_info tinfo;
> +	int ret;
> +
> +	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
> +	if (!opts)
> +		return -ENOMEM;
> +
> +	ret = fcloop_parse_options(opts, buf);
> +	if (ret)
> +		goto out_free_opts;
> +
> +	/* everything there ? */
> +	if ((opts->mask & RPORT_OPTS) != RPORT_OPTS) {
> +		ret = -EINVAL;
> +		goto out_free_opts;
> +	}
> +
> +	pinfo.fabric_name = tinfo.fabric_name = opts->fabric;
> +	pinfo.node_name = tinfo.node_name = opts->wwnn;
> +	pinfo.port_name = tinfo.port_name = opts->wwpn;
> +	pinfo.port_role = opts->roles;
> +	pinfo.port_id = tinfo.port_id = opts->fcaddr;
> +
> +	list_for_each_entry_safe(lport, lnext, &fcloop_lports, list)
> {
> +		if (lport->localport->fabric_name == opts->fabric)
> +			break;
> +	}
> +	if (is_end_of_list(lport, &fcloop_lports, list)) {
> +		ret = -ENOENT;
> +		goto out_free_opts;
> +	}
> +
> +	ret = nvme_fc_register_remoteport(lport->localport, &pinfo,
> +					&remoteport);
> +	if (ret)
> +		goto out_free_opts;
> +
> +	/* success */
> +	rport = remoteport->private;
> +	rport->remoteport = remoteport;
> +	INIT_LIST_HEAD(&rport->list);
> +	list_add_tail(&rport->list, &lport->rport_list);

is there not a mutex or locking mechanism needed when manipulating this
list?

> +
> +	/* tie into nvme target side */
> +	ret = nvmet_fc_register_targetport(&tinfo, &tgttemplate,
> NULL,
> +					&rport->targetport);
> +	if (ret) {
> +		list_del(&rport->list);
> +		(void)nvme_fc_unregister_remoteport(remoteport);
> +	} else {
> +		struct fcloop_tgtport *tport;
> +
> +		tport = rport->targetport->private;
> +		tport->rport = rport;
> +		tport->lport = lport;
> +		tport->tgtport = rport->targetport;
> +
> +		/* mark all of the input buffer consumed */
> +		ret = count;
> +	}
> +
> +out_free_opts:
> +	kfree(opts);
> +	return ret;
> +}
> +

Thanks,
J

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Christoph Hellwig Aug. 11, 2016, 9:23 p.m. UTC | #2
On Fri, Jul 22, 2016 at 05:23:59PM -0700, James Smart wrote:
> 
> Add FC LLDD loopback driver to test FC host and target transport within
> nvme-fabrics
> 
> To aid in the development and testing of the lower-level api of the FC
> transport, this loopback driver has been created to act as if it were a
> FC hba driver supporting both the host interfaces as well as the target
> interfaces with the nvme FC transport.

A proper FC loop device should support SCSI and NVMe.  Any chance to
morph it into one that does both?
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James Smart Aug. 22, 2016, 5:14 p.m. UTC | #3
On 8/2/2016 5:15 PM, J Freyensee wrote:
>
>>   +int
>> +fcloop_fcp_op(struct nvmet_fc_target_port *tgtport,
>> +			struct nvmefc_tgt_fcp_req *tgt_fcpreq)
>> +{
>> +	...
>> +
>> +	return 0;
> if this function returns an 'int', why would it always return 0 and not
> the fcp_err values (if there is an error)?

I'll look at it. The reason it's carried in the tgt_fcpreq is that a 
real LLDD would likely return from the fcp_op, and report an error later 
on. I'll see if things should be reorg'd.


>
>> +struct nvme_fc_port_template fctemplate = {
>> +	.create_queue	= fcloop_create_queue,
>> +	.delete_queue	= fcloop_delete_queue,
>> +	.ls_req		= fcloop_ls_req,
>> +	.fcp_io		= fcloop_fcp_req,
>> +	.ls_abort	= fcloop_ls_abort,
>> +	.fcp_abort	= fcloop_fcp_abort,
>> +
>> +	.max_hw_queues	= 1,
>> +	.max_sgl_segments = 256,
>> +	.max_dif_sgl_segments = 256,
>> +	.dma_boundary = 0xFFFFFFFF,
> Between here and "struct nvmet_fc_target_template tgttemplate" they are
> assigning the same magic values to the same variable names, so why not
> have these values as #defines for a tad easier maintainability?

sure.


>
>> +static ssize_t
>> +fcloop_create_local_port(struct device *dev, struct device_attribute
>> *attr,
>> +		const char *buf, size_t count)
>> +{
>> +	struct nvme_fc_port_info pinfo;
>> +	struct fcloop_ctrl_options *opts;
>> +	struct nvme_fc_local_port *localport;
>> +	struct fcloop_lport *lport;
>> +	int ret;
>> +
>> +	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
>> +	if (!opts)
>> +		return -ENOMEM;
>> +
>> +	ret = fcloop_parse_options(opts, buf);
>> +	if (ret)
>> +		goto out_free_opts;
>> +
>> +	/* everything there ? */
>> +	if ((opts->mask & LPORT_OPTS) != LPORT_OPTS) {
>> +		ret = -EINVAL;
>> +		goto out_free_opts;
>> +	}
>> +
>> +	pinfo.fabric_name = opts->fabric;
>> +	pinfo.node_name = opts->wwnn;
>> +	pinfo.port_name = opts->wwpn;
>> +	pinfo.port_role = opts->roles;
>> +	pinfo.port_id = opts->fcaddr;
>> +
>> +	ret = nvme_fc_register_localport(&pinfo, &fctemplate, NULL,
>> &localport);
>> +	if (!ret) {
>> +		/* success */
>> +		lport = localport->private;
>> +		lport->localport = localport;
>> +		INIT_LIST_HEAD(&lport->list);
>> +		INIT_LIST_HEAD(&lport->rport_list);
>> +		list_add_tail(&lport->list, &fcloop_lports);
>> +
>> +		/* mark all of the input buffer consumed */
>> +		ret = count;
>> +	}
>> +
>> +out_free_opts:
>> +	kfree(opts);
>> +	return ret;
>> +}
>> +
>> +static int __delete_local_port(struct fcloop_lport *lport)
>> +{
>> +	int ret;
>> +
>> +	if (!list_empty(&lport->rport_list))
>> +		return -EBUSY;
>> +
>> +	list_del(&lport->list);
>> +
> Is a mutex or locking mechanism not needed here for this list?

Yeah - could probably use. As it was mainly a test tool with a 
controlled sequence, I think I ignored it.

-- james


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James Smart Aug. 22, 2016, 5:29 p.m. UTC | #4
On 8/11/2016 2:23 PM, Christoph Hellwig wrote:
> On Fri, Jul 22, 2016 at 05:23:59PM -0700, James Smart wrote:
>> Add FC LLDD loopback driver to test FC host and target transport within
>> nvme-fabrics
>>
>> To aid in the development and testing of the lower-level api of the FC
>> transport, this loopback driver has been created to act as if it were a
>> FC hba driver supporting both the host interfaces as well as the target
>> interfaces with the nvme FC transport.
> A proper FC loop device should support SCSI and NVMe.  Any chance to
> morph it into one that does both?

Nope. Not really appropriate for this module, whose goals were to test 
the fc-nvme interfaces. SCSI is a whole different beast.

-- james

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diff mbox

Patch

diff --git a/drivers/nvme/target/Kconfig b/drivers/nvme/target/Kconfig
index 62819b2..a20d41c 100644
--- a/drivers/nvme/target/Kconfig
+++ b/drivers/nvme/target/Kconfig
@@ -44,3 +44,16 @@  config NVME_TARGET_FC
 
 	  If unsure, say N.
 
+config NVME_TARGET_FCLOOP
+	tristate "NVMe over Fabrics FC Transport Loopback Test driver"
+	depends on BLK_DEV_NVME
+	select NVME_TARGET
+	select NVME_FABRICS
+	select SG_POOL
+	select NVME_FC
+	select NVME_TARGET_FC
+	help
+	  This enables the NVMe FC loopback test support, which can be useful
+	  to test NVMe-FC transport interfaces.
+
+	  If unsure, say N.
diff --git a/drivers/nvme/target/Makefile b/drivers/nvme/target/Makefile
index 80b128b..fecc14f 100644
--- a/drivers/nvme/target/Makefile
+++ b/drivers/nvme/target/Makefile
@@ -3,9 +3,11 @@  obj-$(CONFIG_NVME_TARGET)		+= nvmet.o
 obj-$(CONFIG_NVME_TARGET_LOOP)		+= nvme-loop.o
 obj-$(CONFIG_NVME_TARGET_RDMA)		+= nvmet-rdma.o
 obj-$(CONFIG_NVME_TARGET_FC)		+= nvmet-fc.o
+obj-$(CONFIG_NVME_TARGET_FCLOOP)	+= nvme-fcloop.o
 
 nvmet-y		+= core.o configfs.o admin-cmd.o io-cmd.o fabrics-cmd.o \
 			discovery.o
 nvme-loop-y	+= loop.o
 nvmet-rdma-y	+= rdma.o
 nvmet-fc-y	+= fc.o
+nvme-fcloop-y	+= fcloop.o
diff --git a/drivers/nvme/target/fcloop.c b/drivers/nvme/target/fcloop.c
new file mode 100644
index 0000000..277ea61
--- /dev/null
+++ b/drivers/nvme/target/fcloop.c
@@ -0,0 +1,803 @@ 
+/*
+ * Copyright (c) 2016 Avago Technologies.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful.
+ * ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES,
+ * INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
+ * PARTICULAR PURPOSE, OR NON-INFRINGEMENT, ARE DISCLAIMED, EXCEPT TO
+ * THE EXTENT THAT SUCH DISCLAIMERS ARE HELD TO BE LEGALLY INVALID.
+ * See the GNU General Public License for more details, a copy of which
+ * can be found in the file COPYING included with this package
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/module.h>
+#include <linux/parser.h>
+
+#include "../host/nvme.h"
+#include "../target/nvmet.h"
+#include <linux/nvme-fc-driver.h>
+#include <linux/nvme-fc.h>
+
+#define is_end_of_list(pos, head, member) ((&pos->member) == (head))
+
+enum {
+	NVMF_OPT_ERR		= 0,
+	NVMF_OPT_WWNN		= 1 << 0,
+	NVMF_OPT_WWPN		= 1 << 1,
+	NVMF_OPT_ROLES		= 1 << 2,
+	NVMF_OPT_FCADDR		= 1 << 3,
+	NVMF_OPT_FABRIC		= 1 << 5,
+};
+
+struct fcloop_ctrl_options {
+	int			mask;
+	u64			wwnn;
+	u64			wwpn;
+	u32			roles;
+	u32			fcaddr;
+	u64			fabric;
+};
+
+static const match_table_t opt_tokens = {
+	{ NVMF_OPT_WWNN,	"wwnn=%s"	},
+	{ NVMF_OPT_WWPN,	"wwpn=%s"	},
+	{ NVMF_OPT_ROLES,	"roles=%d"	},
+	{ NVMF_OPT_FCADDR,	"fcaddr=%x"	},
+	{ NVMF_OPT_FABRIC,	"fabric=%s"	},
+	{ NVMF_OPT_ERR,		NULL		}
+};
+
+static int
+fcloop_parse_options(struct fcloop_ctrl_options *opts,
+		const char *buf)
+{
+	substring_t args[MAX_OPT_ARGS];
+	char *options, *o, *p;
+	int token, ret = 0;
+	u64 token64;
+
+	options = o = kstrdup(buf, GFP_KERNEL);
+	if (!options)
+		return -ENOMEM;
+
+	while ((p = strsep(&o, ",\n")) != NULL) {
+		if (!*p)
+			continue;
+
+		token = match_token(p, opt_tokens, args);
+		opts->mask |= token;
+		switch (token) {
+		case NVMF_OPT_WWNN:
+			if (match_u64(args, &token64)) {
+				ret = -EINVAL;
+				goto out_free_options;
+			}
+			opts->wwnn = token64;
+			break;
+		case NVMF_OPT_WWPN:
+			if (match_u64(args, &token64)) {
+				ret = -EINVAL;
+				goto out_free_options;
+			}
+			opts->wwpn = token64;
+			break;
+		case NVMF_OPT_ROLES:
+			if (match_int(args, &token)) {
+				ret = -EINVAL;
+				goto out_free_options;
+			}
+			opts->roles = token;
+			break;
+		case NVMF_OPT_FCADDR:
+			if (match_hex(args, &token)) {
+				ret = -EINVAL;
+				goto out_free_options;
+			}
+			opts->fcaddr = token;
+			break;
+		case NVMF_OPT_FABRIC:
+			if (match_u64(args, &token64)) {
+				ret = -EINVAL;
+				goto out_free_options;
+			}
+			opts->fabric = token64;
+			break;
+		default:
+			pr_warn("unknown parameter or missing value '%s'\n", p);
+			ret = -EINVAL;
+			goto out_free_options;
+		}
+	}
+
+out_free_options:
+	kfree(options);
+	return ret;
+}
+
+
+static int
+fcloop_parse_nm_options(struct device *dev, u64 *fname, u64 *pname,
+		const char *buf)
+{
+	substring_t args[MAX_OPT_ARGS];
+	char *options, *o, *p;
+	int token, ret = 0;
+	u64 token64;
+
+	*fname = -1;
+	*pname = -1;
+
+	options = o = kstrdup(buf, GFP_KERNEL);
+	if (!options)
+		return -ENOMEM;
+
+	while ((p = strsep(&o, ",\n")) != NULL) {
+		if (!*p)
+			continue;
+
+		token = match_token(p, opt_tokens, args);
+		switch (token) {
+		case NVMF_OPT_FABRIC:
+			if (match_u64(args, &token64)) {
+				ret = -EINVAL;
+				goto out_free_options;
+			}
+			*fname = token64;
+			break;
+		case NVMF_OPT_WWPN:
+			if (match_u64(args, &token64)) {
+				ret = -EINVAL;
+				goto out_free_options;
+			}
+			*pname = token64;
+			break;
+		default:
+			pr_warn("unknown parameter or missing value '%s'\n", p);
+			ret = -EINVAL;
+			goto out_free_options;
+		}
+	}
+
+out_free_options:
+	kfree(options);
+
+	if (!ret) {
+		if (*fname == -1)
+			return -EINVAL;
+		if (*pname == -1)
+			return -EINVAL;
+	}
+
+	return ret;
+}
+
+
+#define LPORT_OPTS	(NVMF_OPT_WWNN | NVMF_OPT_WWPN | NVMF_OPT_ROLES | \
+			 NVMF_OPT_FCADDR | NVMF_OPT_FABRIC)
+
+#define RPORT_OPTS	(NVMF_OPT_WWNN | NVMF_OPT_WWPN | NVMF_OPT_ROLES | \
+			 NVMF_OPT_FCADDR | NVMF_OPT_FABRIC)
+
+#define TGTPORT_OPTS	(NVMF_OPT_WWNN | NVMF_OPT_WWPN | \
+			 NVMF_OPT_FCADDR | NVMF_OPT_FABRIC)
+
+#define ALL_OPTS	(NVMF_OPT_WWNN | NVMF_OPT_WWPN | NVMF_OPT_ROLES | \
+			 NVMF_OPT_FCADDR | NVMF_OPT_FABRIC)
+
+
+static LIST_HEAD(fcloop_lports);
+
+struct fcloop_lport {
+	struct nvme_fc_local_port *localport;
+	struct list_head list;
+	struct list_head rport_list;
+};
+
+struct fcloop_rport {
+	struct nvme_fc_remote_port *remoteport;
+	struct list_head list;
+	struct nvmet_fc_target_port *targetport;
+};
+
+struct fcloop_tgtport {
+	struct nvmet_fc_target_port *tgtport;
+	struct fcloop_rport *rport;
+	struct fcloop_lport *lport;
+};
+
+
+struct fcloop_lsreq {
+	struct fcloop_tgtport		*tport;
+	struct nvmefc_ls_req		*lsreq;
+	struct work_struct		work;
+	struct nvmefc_tgt_ls_req	tgt_ls_req;
+};
+
+struct fcloop_fcpreq {
+	struct fcloop_tgtport		*tport;
+	struct nvmefc_fcp_req		*fcpreq;
+	u16				status;
+	struct work_struct		work;
+	struct nvmefc_tgt_fcp_req	tgt_fcp_req;
+};
+
+int
+fcloop_create_queue(struct nvme_fc_local_port *localport,
+			unsigned int qidx, u16 qsize,
+			void **handle)
+{
+	*handle = localport;
+	return 0;
+}
+
+void
+fcloop_delete_queue(struct nvme_fc_local_port *localport,
+			unsigned int idx, void *handle)
+{
+}
+
+
+/*
+ * Transmit of LS RSP done (e.g. buffers all set). call back up
+ * initiator "done" flows.
+ */
+void
+fcloop_tgt_lsrqst_done_work(struct work_struct *work)
+{
+	struct fcloop_lsreq *tls_req =
+		container_of(work, struct fcloop_lsreq, work);
+	struct nvmefc_ls_req *lsreq = tls_req->lsreq;
+
+	lsreq->done(lsreq, 0);
+}
+
+int
+fcloop_ls_req(struct nvme_fc_local_port *localport,
+			struct nvme_fc_remote_port *remoteport,
+			struct nvmefc_ls_req *lsreq)
+{
+	struct fcloop_lsreq *tls_req = lsreq->private;
+	struct fcloop_rport *rport = remoteport->private;
+	int ret = 0;
+
+	tls_req->lsreq = lsreq;
+	tls_req->tport = rport->targetport->private;
+	INIT_WORK(&tls_req->work, fcloop_tgt_lsrqst_done_work);
+
+	ret = nvmet_fc_rcv_ls_req(rport->targetport, &tls_req->tgt_ls_req,
+				 lsreq->rqstaddr, lsreq->rqstlen);
+
+	return ret;
+}
+
+int
+fcloop_xmt_ls_rsp(struct nvmet_fc_target_port *tgtport,
+			struct nvmefc_tgt_ls_req *tgt_lsreq)
+{
+	struct fcloop_lsreq *tls_req =
+		container_of(tgt_lsreq, struct fcloop_lsreq, tgt_ls_req);
+	struct nvmefc_ls_req *lsreq = tls_req->lsreq;
+
+	memcpy(lsreq->rspaddr, tgt_lsreq->rspbuf,
+		((lsreq->rsplen < tgt_lsreq->rsplen) ?
+				lsreq->rsplen : tgt_lsreq->rsplen));
+	(tgt_lsreq->done)(tgt_lsreq);
+
+	schedule_work(&tls_req->work);
+
+	return 0;
+}
+
+/*
+ * FCP IO operation done. call back up initiator "done" flows.
+ */
+void
+fcloop_tgt_fcprqst_done_work(struct work_struct *work)
+{
+	struct fcloop_fcpreq *tfcp_req =
+		container_of(work, struct fcloop_fcpreq, work);
+	struct nvmefc_fcp_req *fcpreq = tfcp_req->fcpreq;
+
+	fcpreq->status = tfcp_req->status;
+	fcpreq->done(fcpreq);
+}
+
+
+int
+fcloop_fcp_req(struct nvme_fc_local_port *localport,
+			struct nvme_fc_remote_port *remoteport,
+			void *hw_queue_handle,
+			struct nvmefc_fcp_req *fcpreq)
+{
+	struct fcloop_fcpreq *tfcp_req = fcpreq->private;
+	struct fcloop_rport *rport = remoteport->private;
+	int ret = 0;
+
+	tfcp_req->fcpreq = fcpreq;
+	tfcp_req->tport = rport->targetport->private;
+	INIT_WORK(&tfcp_req->work, fcloop_tgt_fcprqst_done_work);
+
+	ret = nvmet_fc_rcv_fcp_req(rport->targetport, &tfcp_req->tgt_fcp_req,
+				 fcpreq->cmdaddr, fcpreq->cmdlen);
+
+	return ret;
+}
+
+void
+fcloop_fcp_copy_data(u8 op, struct scatterlist *data_sg,
+			struct scatterlist *io_sg, u32 offset, u32 length)
+{
+	void *data_p, *io_p;
+	u32 data_len, io_len, tlen;
+
+	io_p = sg_virt(io_sg);
+	io_len = io_sg->length;
+
+	for ( ; offset; ) {
+		tlen = min_t(u32, offset, io_len);
+		offset -= tlen;
+		io_len -= tlen;
+		if (!io_len) {
+			io_sg = sg_next(io_sg);
+			io_p = sg_virt(io_sg);
+			io_len = io_sg->length;
+		} else
+			io_p += tlen;
+	}
+
+	data_p = sg_virt(data_sg);
+	data_len = data_sg->length;
+
+	for ( ; length; ) {
+		tlen = min_t(u32, io_len, data_len);
+		tlen = min_t(u32, tlen, length);
+
+		if (op == NVMET_FCOP_WRITEDATA)
+			memcpy(data_p, io_p, tlen);
+		else
+			memcpy(io_p, data_p, tlen);
+
+		length -= tlen;
+
+		io_len -= tlen;
+		if ((!io_len) && (length)) {
+			io_sg = sg_next(io_sg);
+			io_p = sg_virt(io_sg);
+			io_len = io_sg->length;
+		} else
+			io_p += tlen;
+
+		data_len -= tlen;
+		if ((!data_len) && (length)) {
+			data_sg = sg_next(data_sg);
+			data_p = sg_virt(data_sg);
+			data_len = data_sg->length;
+		} else
+			data_p += tlen;
+	}
+}
+
+int
+fcloop_fcp_op(struct nvmet_fc_target_port *tgtport,
+			struct nvmefc_tgt_fcp_req *tgt_fcpreq)
+{
+	struct fcloop_fcpreq *tfcp_req =
+		container_of(tgt_fcpreq, struct fcloop_fcpreq, tgt_fcp_req);
+	struct nvmefc_fcp_req *fcpreq = tfcp_req->fcpreq;
+	u32 rsplen = 0, xfrlen = 0;
+	int fcp_err = 0;
+	u8 op = tgt_fcpreq->op;
+
+	switch (op) {
+	case NVMET_FCOP_WRITEDATA:
+		xfrlen = tgt_fcpreq->transfer_length;
+		fcloop_fcp_copy_data(op, tgt_fcpreq->sg, fcpreq->first_sgl,
+					tgt_fcpreq->offset, xfrlen);
+		fcpreq->transferred_length += xfrlen;
+		break;
+
+	case NVMET_FCOP_READDATA:
+	case NVMET_FCOP_READDATA_RSP:
+		xfrlen = tgt_fcpreq->transfer_length;
+		fcloop_fcp_copy_data(op, tgt_fcpreq->sg, fcpreq->first_sgl,
+					tgt_fcpreq->offset, xfrlen);
+		fcpreq->transferred_length += xfrlen;
+		if (op == NVMET_FCOP_READDATA)
+			break;
+
+		/* Fall-Thru to RSP handling */
+
+	case NVMET_FCOP_RSP:
+		rsplen = ((fcpreq->rsplen < tgt_fcpreq->rsplen) ?
+				fcpreq->rsplen : tgt_fcpreq->rsplen);
+		memcpy(fcpreq->rspaddr, tgt_fcpreq->rspaddr, rsplen);
+		if (rsplen < tgt_fcpreq->rsplen)
+			fcp_err = -E2BIG;
+		fcpreq->rcv_rsplen = rsplen;
+		fcpreq->status = 0;
+		tfcp_req->status = 0;
+		break;
+
+	case NVMET_FCOP_ABORT:
+		tfcp_req->status = NVME_SC_FC_TRANSPORT_ABORTED;
+		break;
+
+	default:
+		fcp_err = -EINVAL;
+		break;
+	}
+
+	tgt_fcpreq->transferred_length = xfrlen;
+	tgt_fcpreq->fcp_error = fcp_err;
+	tgt_fcpreq->done(tgt_fcpreq);
+
+	if ((!fcp_err) && (op == NVMET_FCOP_RSP ||
+			op == NVMET_FCOP_READDATA_RSP ||
+			op == NVMET_FCOP_ABORT))
+		schedule_work(&tfcp_req->work);
+
+	return 0;
+}
+
+void
+fcloop_ls_abort(struct nvme_fc_local_port *localport,
+			struct nvme_fc_remote_port *remoteport,
+				struct nvmefc_ls_req *lsreq)
+{
+}
+
+void
+fcloop_fcp_abort(struct nvme_fc_local_port *localport,
+			struct nvme_fc_remote_port *remoteport,
+			void *hw_queue_handle,
+			struct nvmefc_fcp_req *fcpreq)
+{
+}
+
+
+struct nvme_fc_port_template fctemplate = {
+	.create_queue	= fcloop_create_queue,
+	.delete_queue	= fcloop_delete_queue,
+	.ls_req		= fcloop_ls_req,
+	.fcp_io		= fcloop_fcp_req,
+	.ls_abort	= fcloop_ls_abort,
+	.fcp_abort	= fcloop_fcp_abort,
+
+	.max_hw_queues	= 1,
+	.max_sgl_segments = 256,
+	.max_dif_sgl_segments = 256,
+	.dma_boundary = 0xFFFFFFFF,
+	/* sizes of additional private data for data structures */
+	.local_priv_sz	= sizeof(struct fcloop_lport),
+	.remote_priv_sz	= sizeof(struct fcloop_rport),
+	.lsrqst_priv_sz = sizeof(struct fcloop_lsreq),
+	.fcprqst_priv_sz = sizeof(struct fcloop_fcpreq),
+};
+
+struct nvmet_fc_target_template tgttemplate = {
+	.xmt_ls_rsp	= fcloop_xmt_ls_rsp,
+	.fcp_op		= fcloop_fcp_op,
+
+	.max_hw_queues	= 1,
+	.max_sgl_segments = 256,
+	.max_dif_sgl_segments = 256,
+	.dma_boundary = 0xFFFFFFFF,
+
+	/* optional features */
+	.target_features = NVMET_FCTGTFEAT_READDATA_RSP,
+
+	/* sizes of additional private data for data structures */
+	.target_priv_sz = sizeof(struct fcloop_tgtport),
+};
+
+static ssize_t
+fcloop_create_local_port(struct device *dev, struct device_attribute *attr,
+		const char *buf, size_t count)
+{
+	struct nvme_fc_port_info pinfo;
+	struct fcloop_ctrl_options *opts;
+	struct nvme_fc_local_port *localport;
+	struct fcloop_lport *lport;
+	int ret;
+
+	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+	if (!opts)
+		return -ENOMEM;
+
+	ret = fcloop_parse_options(opts, buf);
+	if (ret)
+		goto out_free_opts;
+
+	/* everything there ? */
+	if ((opts->mask & LPORT_OPTS) != LPORT_OPTS) {
+		ret = -EINVAL;
+		goto out_free_opts;
+	}
+
+	pinfo.fabric_name = opts->fabric;
+	pinfo.node_name = opts->wwnn;
+	pinfo.port_name = opts->wwpn;
+	pinfo.port_role = opts->roles;
+	pinfo.port_id = opts->fcaddr;
+
+	ret = nvme_fc_register_localport(&pinfo, &fctemplate, NULL, &localport);
+	if (!ret) {
+		/* success */
+		lport = localport->private;
+		lport->localport = localport;
+		INIT_LIST_HEAD(&lport->list);
+		INIT_LIST_HEAD(&lport->rport_list);
+		list_add_tail(&lport->list, &fcloop_lports);
+
+		/* mark all of the input buffer consumed */
+		ret = count;
+	}
+
+out_free_opts:
+	kfree(opts);
+	return ret;
+}
+
+static int __delete_local_port(struct fcloop_lport *lport)
+{
+	int ret;
+
+	if (!list_empty(&lport->rport_list))
+		return -EBUSY;
+
+	list_del(&lport->list);
+
+	ret = nvme_fc_unregister_localport(lport->localport);
+
+	return ret;
+}
+
+static ssize_t
+fcloop_delete_local_port(struct device *dev, struct device_attribute *attr,
+		const char *buf, size_t count)
+{
+	struct fcloop_lport *lport, *lnext;
+	u64 fabric, portname;
+	int ret;
+
+	ret = fcloop_parse_nm_options(dev, &fabric, &portname, buf);
+	if (ret)
+		return ret;
+
+	list_for_each_entry_safe(lport, lnext, &fcloop_lports, list) {
+		if ((lport->localport->fabric_name == fabric) &&
+		    (lport->localport->port_name == portname)) {
+			break;
+		}
+	}
+	if (is_end_of_list(lport, &fcloop_lports, list))
+		return -ENOENT;
+
+	ret = __delete_local_port(lport);
+
+	if (!ret)
+		return count;
+
+	return ret;
+}
+
+static ssize_t
+fcloop_create_remote_port(struct device *dev, struct device_attribute *attr,
+		const char *buf, size_t count)
+{
+	struct fcloop_ctrl_options *opts;
+	struct fcloop_lport *lport, *lnext;
+	struct nvme_fc_remote_port *remoteport;
+	struct fcloop_rport *rport;
+	struct nvme_fc_port_info pinfo;
+	struct nvmet_fc_port_info tinfo;
+	int ret;
+
+	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+	if (!opts)
+		return -ENOMEM;
+
+	ret = fcloop_parse_options(opts, buf);
+	if (ret)
+		goto out_free_opts;
+
+	/* everything there ? */
+	if ((opts->mask & RPORT_OPTS) != RPORT_OPTS) {
+		ret = -EINVAL;
+		goto out_free_opts;
+	}
+
+	pinfo.fabric_name = tinfo.fabric_name = opts->fabric;
+	pinfo.node_name = tinfo.node_name = opts->wwnn;
+	pinfo.port_name = tinfo.port_name = opts->wwpn;
+	pinfo.port_role = opts->roles;
+	pinfo.port_id = tinfo.port_id = opts->fcaddr;
+
+	list_for_each_entry_safe(lport, lnext, &fcloop_lports, list) {
+		if (lport->localport->fabric_name == opts->fabric)
+			break;
+	}
+	if (is_end_of_list(lport, &fcloop_lports, list)) {
+		ret = -ENOENT;
+		goto out_free_opts;
+	}
+
+	ret = nvme_fc_register_remoteport(lport->localport, &pinfo,
+					&remoteport);
+	if (ret)
+		goto out_free_opts;
+
+	/* success */
+	rport = remoteport->private;
+	rport->remoteport = remoteport;
+	INIT_LIST_HEAD(&rport->list);
+	list_add_tail(&rport->list, &lport->rport_list);
+
+	/* tie into nvme target side */
+	ret = nvmet_fc_register_targetport(&tinfo, &tgttemplate, NULL,
+					&rport->targetport);
+	if (ret) {
+		list_del(&rport->list);
+		(void)nvme_fc_unregister_remoteport(remoteport);
+	} else {
+		struct fcloop_tgtport *tport;
+
+		tport = rport->targetport->private;
+		tport->rport = rport;
+		tport->lport = lport;
+		tport->tgtport = rport->targetport;
+
+		/* mark all of the input buffer consumed */
+		ret = count;
+	}
+
+out_free_opts:
+	kfree(opts);
+	return ret;
+}
+
+static int __delete_remote_port(struct fcloop_rport *rport)
+{
+	int ret;
+
+	ret = nvmet_fc_unregister_targetport(rport->targetport);
+	if (ret)
+		return ret;
+
+	list_del(&rport->list);
+
+	ret = nvme_fc_unregister_remoteport(rport->remoteport);
+
+	return ret;
+}
+
+static ssize_t
+fcloop_delete_remote_port(struct device *dev, struct device_attribute *attr,
+		const char *buf, size_t count)
+{
+	struct fcloop_lport *lport, *lnext;
+	struct fcloop_rport *rport, *rnext;
+	u64 fabric, portname;
+	int ret;
+
+	ret = fcloop_parse_nm_options(dev, &fabric, &portname, buf);
+	if (ret)
+		return ret;
+
+	list_for_each_entry_safe(lport, lnext, &fcloop_lports, list)
+		if (lport->localport->fabric_name == fabric)
+			break;
+	if (is_end_of_list(lport, &fcloop_lports, list))
+		return -ENOENT;
+
+	list_for_each_entry_safe(rport, rnext, &lport->rport_list, list)
+		if (rport->remoteport->port_name == portname)
+			break;
+	if (is_end_of_list(rport, &lport->rport_list, list))
+		return -ENOENT;
+
+	ret = __delete_remote_port(rport);
+	if (!ret)
+		return count;
+
+	return ret;
+}
+
+
+static DEVICE_ATTR(add_local_port, S_IWUSR, NULL, fcloop_create_local_port);
+static DEVICE_ATTR(del_local_port, S_IWUSR, NULL, fcloop_delete_local_port);
+static DEVICE_ATTR(add_remote_port, S_IWUSR, NULL, fcloop_create_remote_port);
+static DEVICE_ATTR(del_remote_port, S_IWUSR, NULL, fcloop_delete_remote_port);
+
+
+static struct class *fcloop_class;
+static struct device *fcloop_device;
+
+
+static int __init fcloop_init(void)
+{
+	int ret;
+
+	fcloop_class = class_create(THIS_MODULE, "fcloop");
+	if (IS_ERR(fcloop_class)) {
+		pr_err("couldn't register class fcloop\n");
+		ret = PTR_ERR(fcloop_class);
+		return ret;
+	}
+
+	fcloop_device =
+		device_create(fcloop_class, NULL, MKDEV(0, 0), NULL, "ctl");
+	if (IS_ERR(fcloop_device)) {
+		pr_err("couldn't create ctl device!\n");
+		ret = PTR_ERR(fcloop_device);
+		goto out_destroy_class;
+	}
+
+	ret = device_create_file(fcloop_device, &dev_attr_add_local_port);
+	if (ret) {
+		pr_err("couldn't add device add_local_port attr.\n");
+		goto out_destroy_device;
+	}
+
+	ret = device_create_file(fcloop_device, &dev_attr_del_local_port);
+	if (ret) {
+		pr_err("couldn't add device del_local_port attr.\n");
+		goto out_destroy_device;
+	}
+
+	ret = device_create_file(fcloop_device, &dev_attr_add_remote_port);
+	if (ret) {
+		pr_err("couldn't add device add_remote_port attr.\n");
+		goto out_destroy_device;
+	}
+
+	ret = device_create_file(fcloop_device, &dev_attr_del_remote_port);
+	if (ret) {
+		pr_err("couldn't add device del_remote_port attr.\n");
+		goto out_destroy_device;
+	}
+
+	return 0;
+
+out_destroy_device:
+	device_destroy(fcloop_class, MKDEV(0, 0));
+out_destroy_class:
+	class_destroy(fcloop_class);
+	return ret;
+}
+
+static void __exit fcloop_exit(void)
+{
+	struct fcloop_lport *lport, *lnext;
+	struct fcloop_rport *rport, *rnext;
+	int ret;
+
+	list_for_each_entry_safe(lport, lnext, &fcloop_lports, list) {
+		list_for_each_entry_safe(rport, rnext,
+						&lport->rport_list, list) {
+			ret = __delete_remote_port(rport);
+			if (ret)
+				pr_warn("%s: Failed deleting remote port\n",
+						__func__);
+
+		}
+		ret = __delete_local_port(lport);
+		if (ret)
+			pr_warn("%s: Failed deleting local port\n", __func__);
+	}
+
+	device_destroy(fcloop_class, MKDEV(0, 0));
+	class_destroy(fcloop_class);
+}
+
+module_init(fcloop_init);
+module_exit(fcloop_exit);
+
+MODULE_LICENSE("GPL v2");
+
+
+