diff mbox series

[v3,12/12] target: add virtual remote target

Message ID 20230313181110.20566-13-d.bogdanov@yadro.com (mailing list archive)
State Accepted
Commit 075a5d356103b32bc7023b03ede60a2f183bcfb3
Headers show
Series add virtual remote fabric | expand

Commit Message

Dmitry Bogdanov March 13, 2023, 6:11 p.m. UTC
Create virtual remote target module.
It can be used to see a whole acl/lun/tpg configuration from all nodes
in storage cluster.
For example, it allows to setup remote ports in ALUA port groups. To
report all ports in a cluster in REPORT TARGET PORT GROUP command.

Suggested-by: Konstantin Shelekhin <k.shelekhin@yadro.com>
Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
---
 v3:
    fix identation and spaces
    simplify init function
---
 drivers/target/Kconfig                 |   1 +
 drivers/target/Makefile                |   1 +
 drivers/target/tcm_remote/Kconfig      |   8 +
 drivers/target/tcm_remote/Makefile     |   2 +
 drivers/target/tcm_remote/tcm_remote.c | 268 +++++++++++++++++++++++++
 drivers/target/tcm_remote/tcm_remote.h |  20 ++
 6 files changed, 300 insertions(+)
 create mode 100644 drivers/target/tcm_remote/Kconfig
 create mode 100644 drivers/target/tcm_remote/Makefile
 create mode 100644 drivers/target/tcm_remote/tcm_remote.c
 create mode 100644 drivers/target/tcm_remote/tcm_remote.h

Comments

Mike Christie March 14, 2023, 5:09 p.m. UTC | #1
On 3/13/23 1:11 PM, Dmitry Bogdanov wrote:
> +
> +static int tcm_remote_port_link(
> +	struct se_portal_group *se_tpg,
> +	struct se_lun *lun)
> +{

Oh no, what happened. Something probably got messed up in your patch
management because I saw the 0/12 patch said the coding style was
fixed up. 

If Martin will take a follow up patch or it's not a big deal to him,
I'm ok.

Reviewed-by: Mike Christie <michael.christie@oracle.com>
Dmitry Bogdanov March 15, 2023, 7:59 a.m. UTC | #2
On Tue, Mar 14, 2023 at 12:09:31PM -0500, Mike Christie wrote:
> 
> On 3/13/23 1:11 PM, Dmitry Bogdanov wrote:
> > +
> > +static int tcm_remote_port_link(
> > +     struct se_portal_group *se_tpg,
> > +     struct se_lun *lun)
> > +{
i> 
> Oh no, what happened. Something probably got messed up in your patch
> management because I saw the 0/12 patch said the coding style was
> fixed up.
> 
> If Martin will take a follow up patch or it's not a big deal to him,
> I'm ok.
> 
> Reviewed-by: Mike Christie <michael.christie@oracle.com>
> 

Mike, the code style is the same as in v2. AFAIR you said not to mix
the first function argument in the same line with the first argument in
the next line. In my patch there is no such mix anymore. Either all
arguments are inline or all arguments in the next lines.
Mike Christie March 15, 2023, 4:13 p.m. UTC | #3
On 3/15/23 2:59 AM, Dmitry Bogdanov wrote:
> On Tue, Mar 14, 2023 at 12:09:31PM -0500, Mike Christie wrote:
>>
>> On 3/13/23 1:11 PM, Dmitry Bogdanov wrote:
>>> +
>>> +static int tcm_remote_port_link(
>>> +     struct se_portal_group *se_tpg,
>>> +     struct se_lun *lun)
>>> +{
> i> 
>> Oh no, what happened. Something probably got messed up in your patch
>> management because I saw the 0/12 patch said the coding style was
>> fixed up.
>>
>> If Martin will take a follow up patch or it's not a big deal to him,
>> I'm ok.
>>
>> Reviewed-by: Mike Christie <michael.christie@oracle.com>
>>
> 
> Mike, the code style is the same as in v2. AFAIR you said not to mix
> the first function argument in the same line with the first argument in
> the next line. In my patch there is no such mix anymore. Either all

We misunderstood each other. I was saying to use style:

static int tcm_remote_port_link(struct se_portal_group *se_tpg, struct se_lun *lun)

or

static int tcm_remote_port_link(struct se_portal_group *se_tpg,
				struct se_lun *lun)

and don't do the specific style you used above :)

I had been using the style I had written above for new code, and trying
to sync us up on one style. I thought the style you used is common in
LIO but not common in the kernel.


> arguments are inline or all arguments in the next lines.
>
diff mbox series

Patch

diff --git a/drivers/target/Kconfig b/drivers/target/Kconfig
index 72171ea3dd53..92641d39126a 100644
--- a/drivers/target/Kconfig
+++ b/drivers/target/Kconfig
@@ -47,5 +47,6 @@  source "drivers/target/loopback/Kconfig"
 source "drivers/target/tcm_fc/Kconfig"
 source "drivers/target/iscsi/Kconfig"
 source "drivers/target/sbp/Kconfig"
+source "drivers/target/tcm_remote/Kconfig"
 
 endif
diff --git a/drivers/target/Makefile b/drivers/target/Makefile
index 45634747377e..431b84abfb94 100644
--- a/drivers/target/Makefile
+++ b/drivers/target/Makefile
@@ -30,3 +30,4 @@  obj-$(CONFIG_LOOPBACK_TARGET)	+= loopback/
 obj-$(CONFIG_TCM_FC)		+= tcm_fc/
 obj-$(CONFIG_ISCSI_TARGET)	+= iscsi/
 obj-$(CONFIG_SBP_TARGET)	+= sbp/
+obj-$(CONFIG_REMOTE_TARGET)	+= tcm_remote/
diff --git a/drivers/target/tcm_remote/Kconfig b/drivers/target/tcm_remote/Kconfig
new file mode 100644
index 000000000000..e6bebb5fe6f1
--- /dev/null
+++ b/drivers/target/tcm_remote/Kconfig
@@ -0,0 +1,8 @@ 
+# SPDX-License-Identifier: GPL-2.0-only
+config REMOTE_TARGET
+	tristate "TCM Virtual Remote target"
+	depends on SCSI
+	help
+	  Say Y here to enable the TCM Virtual Remote fabric
+	  That fabric is a dummy fabric to tell TCM about configuration
+	  of TPG/ACL/LUN on peer nodes in a cluster.
diff --git a/drivers/target/tcm_remote/Makefile b/drivers/target/tcm_remote/Makefile
new file mode 100644
index 000000000000..5818ffd0b0fa
--- /dev/null
+++ b/drivers/target/tcm_remote/Makefile
@@ -0,0 +1,2 @@ 
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_REMOTE_TARGET)	+= tcm_remote.o
diff --git a/drivers/target/tcm_remote/tcm_remote.c b/drivers/target/tcm_remote/tcm_remote.c
new file mode 100644
index 000000000000..cb8db2558056
--- /dev/null
+++ b/drivers/target/tcm_remote/tcm_remote.c
@@ -0,0 +1,268 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/configfs.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_tcq.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_cmnd.h>
+
+#include <target/target_core_base.h>
+#include <target/target_core_fabric.h>
+
+#include "tcm_remote.h"
+
+static inline struct tcm_remote_tpg *remote_tpg(struct se_portal_group *se_tpg)
+{
+	return container_of(se_tpg, struct tcm_remote_tpg, remote_se_tpg);
+}
+
+static char *tcm_remote_get_endpoint_wwn(struct se_portal_group *se_tpg)
+{
+	/*
+	 * Return the passed NAA identifier for the Target Port
+	 */
+	return &remote_tpg(se_tpg)->remote_hba->remote_wwn_address[0];
+}
+
+static u16 tcm_remote_get_tag(struct se_portal_group *se_tpg)
+{
+	/*
+	 * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
+	 * to represent the SCSI Target Port.
+	 */
+	return remote_tpg(se_tpg)->remote_tpgt;
+}
+
+static int tcm_remote_dummy_cmd_fn(struct se_cmd *se_cmd)
+{
+	return 0;
+}
+
+static void tcm_remote_dummy_cmd_void_fn(struct se_cmd *se_cmd)
+{
+
+}
+
+static char *tcm_remote_dump_proto_id(struct tcm_remote_hba *remote_hba)
+{
+	switch (remote_hba->remote_proto_id) {
+	case SCSI_PROTOCOL_SAS:
+		return "SAS";
+	case SCSI_PROTOCOL_SRP:
+		return "SRP";
+	case SCSI_PROTOCOL_FCP:
+		return "FCP";
+	case SCSI_PROTOCOL_ISCSI:
+		return "iSCSI";
+	default:
+		break;
+	}
+
+	return "Unknown";
+}
+
+static int tcm_remote_port_link(
+	struct se_portal_group *se_tpg,
+	struct se_lun *lun)
+{
+	pr_debug("TCM_Remote_ConfigFS: Port Link LUN %lld Successful\n",
+		 lun->unpacked_lun);
+	return 0;
+}
+
+static void tcm_remote_port_unlink(
+	struct se_portal_group *se_tpg,
+	struct se_lun *lun)
+{
+	pr_debug("TCM_Remote_ConfigFS: Port Unlink LUN %lld Successful\n",
+		 lun->unpacked_lun);
+}
+
+static struct se_portal_group *tcm_remote_make_tpg(
+	struct se_wwn *wwn,
+	const char *name)
+{
+	struct tcm_remote_hba *remote_hba = container_of(wwn,
+			struct tcm_remote_hba, remote_hba_wwn);
+	struct tcm_remote_tpg *remote_tpg;
+	unsigned long tpgt;
+	int ret;
+
+	if (strstr(name, "tpgt_") != name) {
+		pr_err("Unable to locate \"tpgt_#\" directory group\n");
+		return ERR_PTR(-EINVAL);
+	}
+	if (kstrtoul(name + 5, 10, &tpgt))
+		return ERR_PTR(-EINVAL);
+
+	if (tpgt >= TL_TPGS_PER_HBA) {
+		pr_err("Passed tpgt: %lu exceeds TL_TPGS_PER_HBA: %u\n",
+		       tpgt, TL_TPGS_PER_HBA);
+		return ERR_PTR(-EINVAL);
+	}
+	remote_tpg = &remote_hba->remote_hba_tpgs[tpgt];
+	remote_tpg->remote_hba = remote_hba;
+	remote_tpg->remote_tpgt = tpgt;
+	/*
+	 * Register the remote_tpg as a emulated TCM Target Endpoint
+	 */
+	ret = core_tpg_register(wwn, &remote_tpg->remote_se_tpg,
+				remote_hba->remote_proto_id);
+	if (ret < 0)
+		return ERR_PTR(-ENOMEM);
+
+	pr_debug("TCM_Remote_ConfigFS: Allocated Emulated %s Target Port %s,t,0x%04lx\n",
+		 tcm_remote_dump_proto_id(remote_hba),
+		 config_item_name(&wwn->wwn_group.cg_item), tpgt);
+	return &remote_tpg->remote_se_tpg;
+}
+
+static void tcm_remote_drop_tpg(struct se_portal_group *se_tpg)
+{
+	struct se_wwn *wwn = se_tpg->se_tpg_wwn;
+	struct tcm_remote_tpg *remote_tpg = container_of(se_tpg,
+				struct tcm_remote_tpg, remote_se_tpg);
+	struct tcm_remote_hba *remote_hba;
+	unsigned short tpgt;
+
+	remote_hba = remote_tpg->remote_hba;
+	tpgt = remote_tpg->remote_tpgt;
+
+	/*
+	 * Deregister the remote_tpg as a emulated TCM Target Endpoint
+	 */
+	core_tpg_deregister(se_tpg);
+
+	remote_tpg->remote_hba = NULL;
+	remote_tpg->remote_tpgt = 0;
+
+	pr_debug("TCM_Remote_ConfigFS: Deallocated Emulated %s Target Port %s,t,0x%04x\n",
+		 tcm_remote_dump_proto_id(remote_hba),
+		 config_item_name(&wwn->wwn_group.cg_item), tpgt);
+}
+
+static struct se_wwn *tcm_remote_make_wwn(
+	struct target_fabric_configfs *tf,
+	struct config_group *group,
+	const char *name)
+{
+	struct tcm_remote_hba *remote_hba;
+	char *ptr;
+	int ret, off = 0;
+
+	remote_hba = kzalloc(sizeof(*remote_hba), GFP_KERNEL);
+	if (!remote_hba)
+		return ERR_PTR(-ENOMEM);
+
+	/*
+	 * Determine the emulated Protocol Identifier and Target Port Name
+	 * based on the incoming configfs directory name.
+	 */
+	ptr = strstr(name, "naa.");
+	if (ptr) {
+		remote_hba->remote_proto_id = SCSI_PROTOCOL_SAS;
+		goto check_len;
+	}
+	ptr = strstr(name, "fc.");
+	if (ptr) {
+		remote_hba->remote_proto_id = SCSI_PROTOCOL_FCP;
+		off = 3; /* Skip over "fc." */
+		goto check_len;
+	}
+	ptr = strstr(name, "0x");
+	if (ptr) {
+		remote_hba->remote_proto_id = SCSI_PROTOCOL_SRP;
+		off = 2; /* Skip over "0x" */
+		goto check_len;
+	}
+	ptr = strstr(name, "iqn.");
+	if (!ptr) {
+		pr_err("Unable to locate prefix for emulated Target Port: %s\n",
+		       name);
+		ret = -EINVAL;
+		goto out;
+	}
+	remote_hba->remote_proto_id = SCSI_PROTOCOL_ISCSI;
+
+check_len:
+	if (strlen(name) >= TL_WWN_ADDR_LEN) {
+		pr_err("Emulated NAA %s Address: %s, exceeds max: %d\n",
+		       name, tcm_remote_dump_proto_id(remote_hba), TL_WWN_ADDR_LEN);
+		ret = -EINVAL;
+		goto out;
+	}
+	snprintf(&remote_hba->remote_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
+
+	pr_debug("TCM_Remote_ConfigFS: Allocated emulated Target %s Address: %s\n",
+		 tcm_remote_dump_proto_id(remote_hba), name);
+	return &remote_hba->remote_hba_wwn;
+out:
+	kfree(remote_hba);
+	return ERR_PTR(ret);
+}
+
+static void tcm_remote_drop_wwn(struct se_wwn *wwn)
+{
+	struct tcm_remote_hba *remote_hba = container_of(wwn,
+				struct tcm_remote_hba, remote_hba_wwn);
+
+	pr_debug("TCM_Remote_ConfigFS: Deallocating emulated Target %s Address: %s\n",
+		 tcm_remote_dump_proto_id(remote_hba),
+		 remote_hba->remote_wwn_address);
+	kfree(remote_hba);
+}
+
+static ssize_t tcm_remote_wwn_version_show(struct config_item *item, char *page)
+{
+	return sprintf(page, "TCM Remote Fabric module %s\n", TCM_REMOTE_VERSION);
+}
+
+CONFIGFS_ATTR_RO(tcm_remote_wwn_, version);
+
+static struct configfs_attribute *tcm_remote_wwn_attrs[] = {
+	&tcm_remote_wwn_attr_version,
+	NULL,
+};
+
+static const struct target_core_fabric_ops remote_ops = {
+	.module				= THIS_MODULE,
+	.fabric_name			= "remote",
+	.tpg_get_wwn			= tcm_remote_get_endpoint_wwn,
+	.tpg_get_tag			= tcm_remote_get_tag,
+	.check_stop_free		= tcm_remote_dummy_cmd_fn,
+	.release_cmd			= tcm_remote_dummy_cmd_void_fn,
+	.write_pending			= tcm_remote_dummy_cmd_fn,
+	.queue_data_in			= tcm_remote_dummy_cmd_fn,
+	.queue_status			= tcm_remote_dummy_cmd_fn,
+	.queue_tm_rsp			= tcm_remote_dummy_cmd_void_fn,
+	.aborted_task			= tcm_remote_dummy_cmd_void_fn,
+	.fabric_make_wwn		= tcm_remote_make_wwn,
+	.fabric_drop_wwn		= tcm_remote_drop_wwn,
+	.fabric_make_tpg		= tcm_remote_make_tpg,
+	.fabric_drop_tpg		= tcm_remote_drop_tpg,
+	.fabric_post_link		= tcm_remote_port_link,
+	.fabric_pre_unlink		= tcm_remote_port_unlink,
+	.tfc_wwn_attrs			= tcm_remote_wwn_attrs,
+};
+
+static int __init tcm_remote_fabric_init(void)
+{
+	return target_register_template(&remote_ops);
+}
+
+static void __exit tcm_remote_fabric_exit(void)
+{
+	target_unregister_template(&remote_ops);
+}
+
+MODULE_DESCRIPTION("TCM virtual remote target");
+MODULE_AUTHOR("Dmitry Bogdanov <d.bogdanov@yadro.com>");
+MODULE_LICENSE("GPL");
+module_init(tcm_remote_fabric_init);
+module_exit(tcm_remote_fabric_exit);
diff --git a/drivers/target/tcm_remote/tcm_remote.h b/drivers/target/tcm_remote/tcm_remote.h
new file mode 100644
index 000000000000..913d1a6eb3a2
--- /dev/null
+++ b/drivers/target/tcm_remote/tcm_remote.h
@@ -0,0 +1,20 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/types.h>
+#include <linux/device.h>
+
+#define TCM_REMOTE_VERSION		"v0.1"
+#define TL_WWN_ADDR_LEN			256
+#define TL_TPGS_PER_HBA			32
+
+struct tcm_remote_tpg {
+	unsigned short remote_tpgt;
+	struct se_portal_group remote_se_tpg;
+	struct tcm_remote_hba *remote_hba;
+};
+
+struct tcm_remote_hba {
+	u8 remote_proto_id;
+	unsigned char remote_wwn_address[TL_WWN_ADDR_LEN];
+	struct tcm_remote_tpg remote_hba_tpgs[TL_TPGS_PER_HBA];
+	struct se_wwn remote_hba_wwn;
+};