summaryrefslogtreecommitdiff
path: root/drivers/target/tcm_remote/tcm_remote.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/target/tcm_remote/tcm_remote.c')
-rw-r--r--drivers/target/tcm_remote/tcm_remote.c268
1 files changed, 268 insertions, 0 deletions
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);