[PATCH v4 0/5] scsi: target: make RTPI an TPG identifier

[PATCH v4 0/5] scsi: target: make RTPI an TPG identifier

[Dmitry Bogdanov]

The patchset based on 6.3/scsi-queue.

SAM-5 4.6.5.2 (Relative Port Identifier attribute) defines the attribute
as unique across SCSI target ports:
 The Relative Port Identifier attribute identifies a SCSI target port or
 a SCSI initiator port relative to other SCSI ports in a SCSI target
 device and any SCSI initiator devices contained within that SCSI target
 device. A SCSI target device may assign relative port identifiers to
 its SCSI target ports and any SCSI initiator ports. If relative port
 identifiers are assigned, the SCSI target device shall assign each of
 its SCSI target ports and any SCSI initiator ports a unique relative
 port identifier from 1 to 65 535. SCSI target ports and SCSI initiator
 ports share the same number space.

In the current TCM implementation, auto-incremented lun_rtpi weakly
follows the model outlined by SAM-5 and SPC-4. In case of multiple SCSI
target ports (se_portal_group's), which is common to scenario with
multiple HBAs or multiple iSCSI/FC targets, it's possible to have two
backstores (se_device's) with different values of lun_rtpi on the same
SCSI target port.

Similar issue happens during re-export. If a LUN of a backstore is
removed from a target port and added again to the same target port, RTPI
is incremented again and will be different from the first time.

The two issues happen because each se_device increments RTPI for its own
LUNs independently.

The behaviour means that a SCSI application client can't reliably make any
sense of RTPI values reported by a LUN as it's not really related to SCSI
target ports. A conforming target implementation must ensure that RTPI field is
unique per port. The patchset resolves the issue.

Make RTPI be part of se_tpg instead of se_lun. Make it configurable.

Changelog:
  v4:
    move rtpi file from tpg_n/attrib to tpgt_n folder (drop 4th patch)
    use unused variable
    make se_tpg.tpg_rtpi variable u16 again
    revert occasional rename

  v3:
    make variable static
    change core_ prefix to target_
    split to tpg_enable/tpg_disable functions

  v2:
    use XArray for tracking RTPI instead of linked list
    do not allow to change RTPI on enabled target port
    drop not needed patches


Dmitry Bogdanov (2):
  scsi: target: core: Add RTPI field to target port
  scsi: target: core: Add RTPI attribute for target port

Roman Bolshakov (2):
  scsi: target: core: Use RTPI from target port
  scsi: target: core: Drop device-based RTPI

 drivers/target/target_core_alua.c            |  4 +-
 drivers/target/target_core_device.c          | 43 +-----------
 drivers/target/target_core_fabric_configfs.c | 44 ++++++++++--
 drivers/target/target_core_internal.h        |  3 +-
 drivers/target/target_core_pr.c              |  8 +--
 drivers/target/target_core_spc.c             |  2 +-
 drivers/target/target_core_stat.c            |  6 +-
 drivers/target/target_core_tpg.c             | 71 ++++++++++++++++++--
 include/target/target_core_base.h            |  7 +-
 9 files changed, 120 insertions(+), 68 deletions(-)

-- 
2.25.1

[PATCH v4 1/4] scsi: target: core: Add RTPI field to target port

[Dmitry Bogdanov]

SAM-5 4.6.5.2 (Relative Port Identifier attribute) defines the attribute
as unique across SCSI target ports.

The change introduces RTPI attribute to se_portal group. The value is
unique across all enabled SCSI target ports. It also limits number of
SCSI target ports to 65535.

Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
---
  v4:
    use unused variable in target_tpg_disable
    make tpg_rtpi variable u16 again

  v3:
    make variable static
    change core_ prefix to target_
    split to tpg_enable/tpg_disable functions

 v2:
   rewrite using XArray to track usage of RTPI
---
 drivers/target/target_core_fabric_configfs.c |  9 ++--
 drivers/target/target_core_internal.h        |  2 +
 drivers/target/target_core_tpg.c             | 54 ++++++++++++++++++++
 include/target/target_core_base.h            |  2 +
 4 files changed, 62 insertions(+), 5 deletions(-)

diff --git a/drivers/target/target_core_fabric_configfs.c b/drivers/target/target_core_fabric_configfs.c
index 67b18a67317a..873da49ab704 100644
--- a/drivers/target/target_core_fabric_configfs.c
+++ b/drivers/target/target_core_fabric_configfs.c
@@ -836,13 +836,12 @@ static ssize_t target_fabric_tpg_base_enable_store(struct config_item *item,
 
 	if (se_tpg->enabled == op)
 		return count;
-
-	ret = se_tpg->se_tpg_tfo->fabric_enable_tpg(se_tpg, op);
+	if (op)
+		ret = target_tpg_enable(se_tpg);
+	else
+		ret = target_tpg_disable(se_tpg);
 	if (ret)
 		return ret;
-
-	se_tpg->enabled = op;
-
 	return count;
 }
 
diff --git a/drivers/target/target_core_internal.h b/drivers/target/target_core_internal.h
index 38a6d08f75b3..82fd5768a662 100644
--- a/drivers/target/target_core_internal.h
+++ b/drivers/target/target_core_internal.h
@@ -132,6 +132,8 @@ void core_tpg_remove_lun(struct se_portal_group *, struct se_lun *);
 struct se_node_acl *core_tpg_add_initiator_node_acl(struct se_portal_group *tpg,
 		const char *initiatorname);
 void core_tpg_del_initiator_node_acl(struct se_node_acl *acl);
+int target_tpg_enable(struct se_portal_group *se_tpg);
+int target_tpg_disable(struct se_portal_group *se_tpg);
 
 /* target_core_transport.c */
 int	init_se_kmem_caches(void);
diff --git a/drivers/target/target_core_tpg.c b/drivers/target/target_core_tpg.c
index 736847c933e5..0de3385b94c5 100644
--- a/drivers/target/target_core_tpg.c
+++ b/drivers/target/target_core_tpg.c
@@ -31,6 +31,7 @@
 #include "target_core_ua.h"
 
 extern struct se_device *g_lun0_dev;
+static DEFINE_XARRAY_ALLOC(tpg_xa);
 
 /*	__core_tpg_get_initiator_node_acl():
  *
@@ -439,6 +440,57 @@ static void core_tpg_lun_ref_release(struct percpu_ref *ref)
 	complete(&lun->lun_shutdown_comp);
 }
 
+static int target_tpg_register_rtpi(struct se_portal_group *se_tpg)
+{
+	u32 val;
+	int ret;
+
+	ret = xa_alloc(&tpg_xa, &val, se_tpg,
+		       XA_LIMIT(1, USHRT_MAX), GFP_KERNEL);
+	if (!ret)
+		se_tpg->tpg_rtpi = val;
+
+	return ret;
+}
+
+static void target_tpg_deregister_rtpi(struct se_portal_group *se_tpg)
+{
+	if (se_tpg->tpg_rtpi && se_tpg->enabled)
+		xa_erase(&tpg_xa, se_tpg->tpg_rtpi);
+}
+
+int target_tpg_enable(struct se_portal_group *se_tpg)
+{
+	int ret;
+
+	ret = target_tpg_register_rtpi(se_tpg);
+	if (ret)
+		return ret;
+
+	ret = se_tpg->se_tpg_tfo->fabric_enable_tpg(se_tpg, true);
+	if (ret) {
+		target_tpg_deregister_rtpi(se_tpg);
+		return ret;
+	}
+
+	se_tpg->enabled = true;
+
+	return 0;
+}
+
+int target_tpg_disable(struct se_portal_group *se_tpg)
+{
+	int ret;
+
+	target_tpg_deregister_rtpi(se_tpg);
+
+	ret = se_tpg->se_tpg_tfo->fabric_enable_tpg(se_tpg, false);
+	if (!ret)
+		se_tpg->enabled = false;
+
+	return ret;
+}
+
 /* Does not change se_wwn->priv. */
 int core_tpg_register(
 	struct se_wwn *se_wwn,
@@ -535,6 +587,8 @@ int core_tpg_deregister(struct se_portal_group *se_tpg)
 		kfree_rcu(se_tpg->tpg_virt_lun0, rcu_head);
 	}
 
+	target_tpg_deregister_rtpi(se_tpg);
+
 	return 0;
 }
 EXPORT_SYMBOL(core_tpg_deregister);
diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h
index 12c9ba16217e..814edf746395 100644
--- a/include/target/target_core_base.h
+++ b/include/target/target_core_base.h
@@ -920,6 +920,8 @@ struct se_portal_group {
 	 */
 	int			proto_id;
 	bool			enabled;
+	/* RELATIVE TARGET PORT IDENTIFIER */
+	u16			tpg_rtpi;
 	/* Used for PR SPEC_I_PT=1 and REGISTER_AND_MOVE */
 	atomic_t		tpg_pr_ref_count;
 	/* Spinlock for adding/removing ACLed Nodes */
-- 
2.25.1

[PATCH v4 2/4] scsi: target: core: Use RTPI from target port

[Dmitry Bogdanov]

From: Roman Bolshakov <r.bolshakov@yadro.com>

Replace all references to RTPI from LUN field to se_portal_group field.
It introduces consitent reporting of RTPI for all LUNs and all target
ports.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
---
 drivers/target/target_core_alua.c   | 4 ++--
 drivers/target/target_core_device.c | 2 +-
 drivers/target/target_core_pr.c     | 8 ++++----
 drivers/target/target_core_spc.c    | 2 +-
 drivers/target/target_core_stat.c   | 6 +++---
 5 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/target/target_core_alua.c b/drivers/target/target_core_alua.c
index c8470e7c0e10..3372856319f7 100644
--- a/drivers/target/target_core_alua.c
+++ b/drivers/target/target_core_alua.c
@@ -225,7 +225,7 @@ target_emulate_report_target_port_groups(struct se_cmd *cmd)
 			/*
 			 * Set RELATIVE TARGET PORT IDENTIFIER
 			 */
-			put_unaligned_be16(lun->lun_rtpi, &buf[off]);
+			put_unaligned_be16(lun->lun_tpg->tpg_rtpi, &buf[off]);
 			off += 2;
 			rd_len += 4;
 		}
@@ -399,7 +399,7 @@ target_emulate_set_target_port_groups(struct se_cmd *cmd)
 			spin_lock(&dev->se_port_lock);
 			list_for_each_entry(lun, &dev->dev_sep_list,
 							lun_dev_link) {
-				if (lun->lun_rtpi != rtpi)
+				if (lun->lun_tpg->tpg_rtpi != rtpi)
 					continue;
 
 				// XXX: racy unlock
diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c
index f6e58410ec3f..93f7f050fdf1 100644
--- a/drivers/target/target_core_device.c
+++ b/drivers/target/target_core_device.c
@@ -223,7 +223,7 @@ struct se_dev_entry *core_get_se_deve_from_rtpi(
 				tpg->se_tpg_tfo->fabric_name);
 			continue;
 		}
-		if (lun->lun_rtpi != rtpi)
+		if (lun->lun_tpg->tpg_rtpi != rtpi)
 			continue;
 
 		kref_get(&deve->pr_kref);
diff --git a/drivers/target/target_core_pr.c b/drivers/target/target_core_pr.c
index 1493b1d01194..d19ec4e6a4c0 100644
--- a/drivers/target/target_core_pr.c
+++ b/drivers/target/target_core_pr.c
@@ -663,7 +663,7 @@ static struct t10_pr_registration *__core_scsi3_do_alloc_registration(
 	}
 	pr_reg->pr_res_mapped_lun = mapped_lun;
 	pr_reg->pr_aptpl_target_lun = lun->unpacked_lun;
-	pr_reg->tg_pt_sep_rtpi = lun->lun_rtpi;
+	pr_reg->tg_pt_sep_rtpi = lun->lun_tpg->tpg_rtpi;
 	pr_reg->pr_res_key = sa_res_key;
 	pr_reg->pr_reg_all_tg_pt = all_tg_pt;
 	pr_reg->pr_reg_aptpl = aptpl;
@@ -967,7 +967,7 @@ static int __core_scsi3_check_aptpl_registration(
 			rcu_read_unlock();
 
 			pr_reg->pr_reg_nacl = nacl;
-			pr_reg->tg_pt_sep_rtpi = lun->lun_rtpi;
+			pr_reg->tg_pt_sep_rtpi = lun->lun_tpg->tpg_rtpi;
 			list_del(&pr_reg->pr_reg_aptpl_list);
 			spin_unlock(&pr_tmpl->aptpl_reg_lock);
 			/*
@@ -1567,7 +1567,7 @@ core_scsi3_decode_spec_i_port(
 			 */
 			if (tmp_tpg->proto_id != proto_ident)
 				continue;
-			dest_rtpi = tmp_lun->lun_rtpi;
+			dest_rtpi = tmp_lun->lun_tpg->tpg_rtpi;
 
 			iport_ptr = NULL;
 			i_str = target_parse_pr_out_transport_id(tmp_tpg,
@@ -3225,7 +3225,7 @@ core_scsi3_emulate_pro_register_and_move(struct se_cmd *cmd, u64 res_key,
 
 	spin_lock(&dev->se_port_lock);
 	list_for_each_entry(tmp_lun, &dev->dev_sep_list, lun_dev_link) {
-		if (tmp_lun->lun_rtpi != rtpi)
+		if (tmp_lun->lun_tpg->tpg_rtpi != rtpi)
 			continue;
 		dest_se_tpg = tmp_lun->lun_tpg;
 		dest_tf_ops = dest_se_tpg->se_tpg_tfo;
diff --git a/drivers/target/target_core_spc.c b/drivers/target/target_core_spc.c
index fcc7b10a7ae3..5bae45c3fb65 100644
--- a/drivers/target/target_core_spc.c
+++ b/drivers/target/target_core_spc.c
@@ -317,7 +317,7 @@ spc_emulate_evpd_83(struct se_cmd *cmd, unsigned char *buf)
 		/* Skip over Obsolete field in RTPI payload
 		 * in Table 472 */
 		off += 2;
-		put_unaligned_be16(lun->lun_rtpi, &buf[off]);
+		put_unaligned_be16(lun->lun_tpg->tpg_rtpi, &buf[off]);
 		off += 2;
 		len += 8; /* Header size + Designation descriptor */
 		/*
diff --git a/drivers/target/target_core_stat.c b/drivers/target/target_core_stat.c
index f85ee5b0fd80..c42cbde8a31b 100644
--- a/drivers/target/target_core_stat.c
+++ b/drivers/target/target_core_stat.c
@@ -455,7 +455,7 @@ static ssize_t target_stat_port_indx_show(struct config_item *item, char *page)
 	rcu_read_lock();
 	dev = rcu_dereference(lun->lun_se_dev);
 	if (dev)
-		ret = snprintf(page, PAGE_SIZE, "%u\n", lun->lun_rtpi);
+		ret = snprintf(page, PAGE_SIZE, "%u\n", lun->lun_tpg->tpg_rtpi);
 	rcu_read_unlock();
 	return ret;
 }
@@ -561,7 +561,7 @@ static ssize_t target_stat_tgt_port_indx_show(struct config_item *item,
 	rcu_read_lock();
 	dev = rcu_dereference(lun->lun_se_dev);
 	if (dev)
-		ret = snprintf(page, PAGE_SIZE, "%u\n", lun->lun_rtpi);
+		ret = snprintf(page, PAGE_SIZE, "%u\n", lun->lun_tpg->tpg_rtpi);
 	rcu_read_unlock();
 	return ret;
 }
@@ -579,7 +579,7 @@ static ssize_t target_stat_tgt_port_name_show(struct config_item *item,
 	if (dev)
 		ret = snprintf(page, PAGE_SIZE, "%sPort#%u\n",
 			tpg->se_tpg_tfo->fabric_name,
-			lun->lun_rtpi);
+			lun->lun_tpg->tpg_rtpi);
 	rcu_read_unlock();
 	return ret;
 }
-- 
2.25.1

[PATCH v4 3/4] scsi: target: core: Drop device-based RTPI

[Dmitry Bogdanov]

From: Roman Bolshakov <r.bolshakov@yadro.com>

The code is not needed since target port-based RTPI allocation replaced
it.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
---
 drivers/target/target_core_device.c   | 41 ---------------------------
 drivers/target/target_core_internal.h |  1 -
 drivers/target/target_core_tpg.c      |  6 ----
 include/target/target_core_base.h     |  4 ---
 4 files changed, 52 deletions(-)

diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c
index 93f7f050fdf1..a3292eade6ea 100644
--- a/drivers/target/target_core_device.c
+++ b/drivers/target/target_core_device.c
@@ -479,47 +479,6 @@ void core_clear_lun_from_tpg(struct se_lun *lun, struct se_portal_group *tpg)
 	mutex_unlock(&tpg->acl_node_mutex);
 }
 
-int core_alloc_rtpi(struct se_lun *lun, struct se_device *dev)
-{
-	struct se_lun *tmp;
-
-	spin_lock(&dev->se_port_lock);
-	if (dev->export_count == 0x0000ffff) {
-		pr_warn("Reached dev->dev_port_count =="
-				" 0x0000ffff\n");
-		spin_unlock(&dev->se_port_lock);
-		return -ENOSPC;
-	}
-again:
-	/*
-	 * Allocate the next RELATIVE TARGET PORT IDENTIFIER for this struct se_device
-	 * Here is the table from spc4r17 section 7.7.3.8.
-	 *
-	 *    Table 473 -- RELATIVE TARGET PORT IDENTIFIER field
-	 *
-	 * Code      Description
-	 * 0h        Reserved
-	 * 1h        Relative port 1, historically known as port A
-	 * 2h        Relative port 2, historically known as port B
-	 * 3h to FFFFh    Relative port 3 through 65 535
-	 */
-	lun->lun_rtpi = dev->dev_rpti_counter++;
-	if (!lun->lun_rtpi)
-		goto again;
-
-	list_for_each_entry(tmp, &dev->dev_sep_list, lun_dev_link) {
-		/*
-		 * Make sure RELATIVE TARGET PORT IDENTIFIER is unique
-		 * for 16-bit wrap..
-		 */
-		if (lun->lun_rtpi == tmp->lun_rtpi)
-			goto again;
-	}
-	spin_unlock(&dev->se_port_lock);
-
-	return 0;
-}
-
 static void se_release_vpd_for_dev(struct se_device *dev)
 {
 	struct t10_vpd *vpd, *vpd_tmp;
diff --git a/drivers/target/target_core_internal.h b/drivers/target/target_core_internal.h
index 82fd5768a662..9c3bca552bb9 100644
--- a/drivers/target/target_core_internal.h
+++ b/drivers/target/target_core_internal.h
@@ -59,7 +59,6 @@ struct target_fabric_configfs {
 extern struct t10_alua_lu_gp *default_lu_gp;
 
 /* target_core_device.c */
-int	core_alloc_rtpi(struct se_lun *lun, struct se_device *dev);
 struct se_dev_entry *core_get_se_deve_from_rtpi(struct se_node_acl *, u16);
 void	target_pr_kref_release(struct kref *);
 void	core_free_device_list_for_node(struct se_node_acl *,
diff --git a/drivers/target/target_core_tpg.c b/drivers/target/target_core_tpg.c
index 0de3385b94c5..b1d9383386ec 100644
--- a/drivers/target/target_core_tpg.c
+++ b/drivers/target/target_core_tpg.c
@@ -632,10 +632,6 @@ int core_tpg_add_lun(
 	if (ret < 0)
 		goto out;
 
-	ret = core_alloc_rtpi(lun, dev);
-	if (ret)
-		goto out_kill_ref;
-
 	if (!(dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA) &&
 	    !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
 		target_attach_tg_pt_gp(lun, dev->t10_alua.default_tg_pt_gp);
@@ -659,8 +655,6 @@ int core_tpg_add_lun(
 
 	return 0;
 
-out_kill_ref:
-	percpu_ref_exit(&lun->lun_ref);
 out:
 	return ret;
 }
diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h
index 814edf746395..008e0e4500d1 100644
--- a/include/target/target_core_base.h
+++ b/include/target/target_core_base.h
@@ -735,8 +735,6 @@ struct se_lun {
 	bool			lun_access_ro;
 	u32			lun_index;
 
-	/* RELATIVE TARGET PORT IDENTIFER */
-	u16			lun_rtpi;
 	atomic_t		lun_acl_count;
 	struct se_device __rcu	*lun_se_dev;
 
@@ -788,8 +786,6 @@ struct se_device_queue {
 };
 
 struct se_device {
-	/* RELATIVE TARGET PORT IDENTIFER Counter */
-	u16			dev_rpti_counter;
 	/* Used for SAM Task Attribute ordering */
 	u32			dev_cur_ordered_id;
 	u32			dev_flags;
-- 
2.25.1

[PATCH v4 4/4] scsi: target: core: Add RTPI attribute for target port

[Dmitry Bogdanov]

RELATIVE TARGET PORT IDENTIFIER can be read and configured via configfs:
$ echo 0x10 > $TARGET/tpgt_N/rtpi

RTPI can be changed only on disabled target ports.

Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
---
 v4:
    move rtpi file from tpgt_n/attrib to tpgt_n folder
    revert occasional rename of core_tpg_remove_lun

 v3:
    change core_ prefix to target_

 v2:
   do not allow to change RTPI on enabled target port
---
 drivers/target/target_core_fabric_configfs.c | 39 +++++++++++++++++++-
 drivers/target/target_core_tpg.c             | 19 ++++++++--
 include/target/target_core_base.h            |  1 +
 3 files changed, 53 insertions(+), 6 deletions(-)

diff --git a/drivers/target/target_core_fabric_configfs.c b/drivers/target/target_core_fabric_configfs.c
index 873da49ab704..a4235309da1d 100644
--- a/drivers/target/target_core_fabric_configfs.c
+++ b/drivers/target/target_core_fabric_configfs.c
@@ -844,15 +844,48 @@ static ssize_t target_fabric_tpg_base_enable_store(struct config_item *item,
 		return ret;
 	return count;
 }
+static ssize_t target_fabric_tpg_base_rtpi_show(struct config_item *item, char *page)
+{
+	struct se_portal_group *se_tpg = attrib_to_tpg(item);
+
+	return sysfs_emit(page, "%#x\n", se_tpg->tpg_rtpi);
+}
+
+static ssize_t target_fabric_tpg_base_rtpi_store(struct config_item *item,
+				   const char *page, size_t count)
+{
+	struct se_portal_group *se_tpg = attrib_to_tpg(item);
+	u16 val;
+	int ret;
+
+	ret = kstrtou16(page, 0, &val);
+	if (ret < 0)
+		return ret;
+	if (val == 0)
+		return -EINVAL;
+
+	if (se_tpg->enabled) {
+		pr_info("%s_TPG[%hu] - Can not change RTPI on enabled TPG",
+			se_tpg->se_tpg_tfo->fabric_name,
+			se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
+		return -EINVAL;
+	}
+
+	se_tpg->tpg_rtpi = val;
+	se_tpg->rtpi_manual = true;
+
+	return count;
+}
 
 CONFIGFS_ATTR(target_fabric_tpg_base_, enable);
+CONFIGFS_ATTR(target_fabric_tpg_base_, rtpi);
 
 static int
 target_fabric_setup_tpg_base_cit(struct target_fabric_configfs *tf)
 {
 	struct config_item_type *cit = &tf->tf_tpg_base_cit;
 	struct configfs_attribute **attrs = NULL;
-	size_t nr_attrs = 0;
+	size_t nr_attrs = 1;
 	int i = 0;
 
 	if (tf->tf_ops->tfc_tpg_base_attrs)
@@ -875,7 +908,9 @@ target_fabric_setup_tpg_base_cit(struct target_fabric_configfs *tf)
 			attrs[i] = tf->tf_ops->tfc_tpg_base_attrs[i];
 
 	if (tf->tf_ops->fabric_enable_tpg)
-		attrs[i] = &target_fabric_tpg_base_attr_enable;
+		attrs[i++] = &target_fabric_tpg_base_attr_enable;
+
+	attrs[i++] = &target_fabric_tpg_base_attr_rtpi;
 
 done:
 	cit->ct_item_ops = &target_fabric_tpg_base_item_ops;
diff --git a/drivers/target/target_core_tpg.c b/drivers/target/target_core_tpg.c
index b1d9383386ec..2e079c6a8e8c 100644
--- a/drivers/target/target_core_tpg.c
+++ b/drivers/target/target_core_tpg.c
@@ -445,10 +445,21 @@ static int target_tpg_register_rtpi(struct se_portal_group *se_tpg)
 	u32 val;
 	int ret;
 
-	ret = xa_alloc(&tpg_xa, &val, se_tpg,
-		       XA_LIMIT(1, USHRT_MAX), GFP_KERNEL);
-	if (!ret)
-		se_tpg->tpg_rtpi = val;
+	if (se_tpg->rtpi_manual) {
+		ret = xa_insert(&tpg_xa, se_tpg->tpg_rtpi, se_tpg, GFP_KERNEL);
+		if (ret) {
+			pr_info("%s_TPG[%hu] - Can not set RTPI %#x, it is already busy",
+				se_tpg->se_tpg_tfo->fabric_name,
+				se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg),
+				se_tpg->tpg_rtpi);
+			return -EINVAL;
+		}
+	} else {
+		ret = xa_alloc(&tpg_xa, &val, se_tpg,
+			       XA_LIMIT(1, USHRT_MAX), GFP_KERNEL);
+		if (!ret)
+			se_tpg->tpg_rtpi = val;
+	}
 
 	return ret;
 }
diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h
index 008e0e4500d1..e52d0915b3d8 100644
--- a/include/target/target_core_base.h
+++ b/include/target/target_core_base.h
@@ -918,6 +918,7 @@ struct se_portal_group {
 	bool			enabled;
 	/* RELATIVE TARGET PORT IDENTIFIER */
 	u16			tpg_rtpi;
+	bool			rtpi_manual;
 	/* Used for PR SPEC_I_PT=1 and REGISTER_AND_MOVE */
 	atomic_t		tpg_pr_ref_count;
 	/* Spinlock for adding/removing ACLed Nodes */
-- 
2.25.1

Re: [PATCH v4 4/4] scsi: target: core: Add RTPI attribute for target port

[Mike Christie]

On 2/21/23 10:06 AM, Dmitry Bogdanov wrote:
> +static ssize_t target_fabric_tpg_base_rtpi_show(struct config_item *item, char *page)
> +{
> +	struct se_portal_group *se_tpg = attrib_to_tpg(item);

..

> +
> +static ssize_t target_fabric_tpg_base_rtpi_store(struct config_item *item,
> +				   const char *page, size_t count)
> +{
> +	struct se_portal_group *se_tpg = attrib_to_tpg(item);


This interface is nicer. It doesn't work for me though. I think
it's because attrib_to_tpg is returning a bogus pointer. The rtpi
file is not in the attrib group so I think you have to use to_tpg().
Or, put the rtpi file in the attrib group if that's preferred (it
doesn't matter to me).

Re: [PATCH v4 4/4] scsi: target: core: Add RTPI attribute for target port

[Dmitry Bogdanov]

On Wed, Feb 22, 2023 at 03:41:20PM -0600, Mike Christie wrote:
> 
> On 2/21/23 10:06 AM, Dmitry Bogdanov wrote:
> > +static ssize_t target_fabric_tpg_base_rtpi_show(struct config_item *item, char *page)
> > +{
> > +     struct se_portal_group *se_tpg = attrib_to_tpg(item);
> 
> ..
> 
> > +
> > +static ssize_t target_fabric_tpg_base_rtpi_store(struct config_item *item,
> > +                                const char *page, size_t count)
> > +{
> > +     struct se_portal_group *se_tpg = attrib_to_tpg(item);
> 
> 
> This interface is nicer. It doesn't work for me though. I think
> it's because attrib_to_tpg is returning a bogus pointer. The rtpi
> file is not in the attrib group so I think you have to use to_tpg().
> Or, put the rtpi file in the attrib group if that's preferred (it
> doesn't matter to me).

Yes, I should use to_tpg. Forgot to change it after moving to tpgt_n
folder. Read after write was working for me so I didn't suspect
something was wrong.