linux/drivers/target/target_core_tpg.c
Mike Christie 530c6891b1 target: allow ALUA setup for some passthrough backends
This patch allows passthrough backends to use the core/base LIO
ALUA setup and state checks, but still handle the execution of
commands.

This will allow the target_core_user module to execute STPG and RTPG
in userspace, and not have to duplicate the ALUA state checks, path
information (needed so we can check if command is executable on
specific paths) and setup (rtslib sets/updates the configfs ALUA
interface like it does for iblock or file).

For STPG, the target_core_user userspace daemon, tcmu-runner will
still execute the STPG, and to update the core/base LIO state it
will use the existing configfs interface. For RTPG, tcmu-runner
will loop over configfs and/or cache the state.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-03-18 14:47:25 -07:00

670 lines
18 KiB
C

/*******************************************************************************
* Filename: target_core_tpg.c
*
* This file contains generic Target Portal Group related functions.
*
* (c) Copyright 2002-2013 Datera, Inc.
*
* Nicholas A. Bellinger <nab@kernel.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
******************************************************************************/
#include <linux/net.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/in.h>
#include <linux/export.h>
#include <net/sock.h>
#include <net/tcp.h>
#include <scsi/scsi_proto.h>
#include <target/target_core_base.h>
#include <target/target_core_backend.h>
#include <target/target_core_fabric.h>
#include "target_core_internal.h"
#include "target_core_alua.h"
#include "target_core_pr.h"
#include "target_core_ua.h"
extern struct se_device *g_lun0_dev;
static DEFINE_SPINLOCK(tpg_lock);
static LIST_HEAD(tpg_list);
/* __core_tpg_get_initiator_node_acl():
*
* mutex_lock(&tpg->acl_node_mutex); must be held when calling
*/
struct se_node_acl *__core_tpg_get_initiator_node_acl(
struct se_portal_group *tpg,
const char *initiatorname)
{
struct se_node_acl *acl;
list_for_each_entry(acl, &tpg->acl_node_list, acl_list) {
if (!strcmp(acl->initiatorname, initiatorname))
return acl;
}
return NULL;
}
/* core_tpg_get_initiator_node_acl():
*
*
*/
struct se_node_acl *core_tpg_get_initiator_node_acl(
struct se_portal_group *tpg,
unsigned char *initiatorname)
{
struct se_node_acl *acl;
/*
* Obtain se_node_acl->acl_kref using fabric driver provided
* initiatorname[] during node acl endpoint lookup driven by
* new se_session login.
*
* The reference is held until se_session shutdown -> release
* occurs via fabric driver invoked transport_deregister_session()
* or transport_free_session() code.
*/
mutex_lock(&tpg->acl_node_mutex);
acl = __core_tpg_get_initiator_node_acl(tpg, initiatorname);
if (acl) {
if (!kref_get_unless_zero(&acl->acl_kref))
acl = NULL;
}
mutex_unlock(&tpg->acl_node_mutex);
return acl;
}
EXPORT_SYMBOL(core_tpg_get_initiator_node_acl);
void core_allocate_nexus_loss_ua(
struct se_node_acl *nacl)
{
struct se_dev_entry *deve;
if (!nacl)
return;
rcu_read_lock();
hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link)
core_scsi3_ua_allocate(deve, 0x29,
ASCQ_29H_NEXUS_LOSS_OCCURRED);
rcu_read_unlock();
}
EXPORT_SYMBOL(core_allocate_nexus_loss_ua);
/* core_tpg_add_node_to_devs():
*
*
*/
void core_tpg_add_node_to_devs(
struct se_node_acl *acl,
struct se_portal_group *tpg,
struct se_lun *lun_orig)
{
bool lun_access_ro = true;
struct se_lun *lun;
struct se_device *dev;
mutex_lock(&tpg->tpg_lun_mutex);
hlist_for_each_entry_rcu(lun, &tpg->tpg_lun_hlist, link) {
if (lun_orig && lun != lun_orig)
continue;
dev = rcu_dereference_check(lun->lun_se_dev,
lockdep_is_held(&tpg->tpg_lun_mutex));
/*
* By default in LIO-Target $FABRIC_MOD,
* demo_mode_write_protect is ON, or READ_ONLY;
*/
if (!tpg->se_tpg_tfo->tpg_check_demo_mode_write_protect(tpg)) {
lun_access_ro = false;
} else {
/*
* Allow only optical drives to issue R/W in default RO
* demo mode.
*/
if (dev->transport->get_device_type(dev) == TYPE_DISK)
lun_access_ro = true;
else
lun_access_ro = false;
}
pr_debug("TARGET_CORE[%s]->TPG[%u]_LUN[%llu] - Adding %s"
" access for LUN in Demo Mode\n",
tpg->se_tpg_tfo->get_fabric_name(),
tpg->se_tpg_tfo->tpg_get_tag(tpg), lun->unpacked_lun,
lun_access_ro ? "READ-ONLY" : "READ-WRITE");
core_enable_device_list_for_node(lun, NULL, lun->unpacked_lun,
lun_access_ro, acl, tpg);
/*
* Check to see if there are any existing persistent reservation
* APTPL pre-registrations that need to be enabled for this dynamic
* LUN ACL now..
*/
core_scsi3_check_aptpl_registration(dev, tpg, lun, acl,
lun->unpacked_lun);
}
mutex_unlock(&tpg->tpg_lun_mutex);
}
static void
target_set_nacl_queue_depth(struct se_portal_group *tpg,
struct se_node_acl *acl, u32 queue_depth)
{
acl->queue_depth = queue_depth;
if (!acl->queue_depth) {
pr_warn("Queue depth for %s Initiator Node: %s is 0,"
"defaulting to 1.\n", tpg->se_tpg_tfo->get_fabric_name(),
acl->initiatorname);
acl->queue_depth = 1;
}
}
static struct se_node_acl *target_alloc_node_acl(struct se_portal_group *tpg,
const unsigned char *initiatorname)
{
struct se_node_acl *acl;
u32 queue_depth;
acl = kzalloc(max(sizeof(*acl), tpg->se_tpg_tfo->node_acl_size),
GFP_KERNEL);
if (!acl)
return NULL;
INIT_LIST_HEAD(&acl->acl_list);
INIT_LIST_HEAD(&acl->acl_sess_list);
INIT_HLIST_HEAD(&acl->lun_entry_hlist);
kref_init(&acl->acl_kref);
init_completion(&acl->acl_free_comp);
spin_lock_init(&acl->nacl_sess_lock);
mutex_init(&acl->lun_entry_mutex);
atomic_set(&acl->acl_pr_ref_count, 0);
if (tpg->se_tpg_tfo->tpg_get_default_depth)
queue_depth = tpg->se_tpg_tfo->tpg_get_default_depth(tpg);
else
queue_depth = 1;
target_set_nacl_queue_depth(tpg, acl, queue_depth);
snprintf(acl->initiatorname, TRANSPORT_IQN_LEN, "%s", initiatorname);
acl->se_tpg = tpg;
acl->acl_index = scsi_get_new_index(SCSI_AUTH_INTR_INDEX);
tpg->se_tpg_tfo->set_default_node_attributes(acl);
return acl;
}
static void target_add_node_acl(struct se_node_acl *acl)
{
struct se_portal_group *tpg = acl->se_tpg;
mutex_lock(&tpg->acl_node_mutex);
list_add_tail(&acl->acl_list, &tpg->acl_node_list);
mutex_unlock(&tpg->acl_node_mutex);
pr_debug("%s_TPG[%hu] - Added %s ACL with TCQ Depth: %d for %s"
" Initiator Node: %s\n",
tpg->se_tpg_tfo->get_fabric_name(),
tpg->se_tpg_tfo->tpg_get_tag(tpg),
acl->dynamic_node_acl ? "DYNAMIC" : "",
acl->queue_depth,
tpg->se_tpg_tfo->get_fabric_name(),
acl->initiatorname);
}
bool target_tpg_has_node_acl(struct se_portal_group *tpg,
const char *initiatorname)
{
struct se_node_acl *acl;
bool found = false;
mutex_lock(&tpg->acl_node_mutex);
list_for_each_entry(acl, &tpg->acl_node_list, acl_list) {
if (!strcmp(acl->initiatorname, initiatorname)) {
found = true;
break;
}
}
mutex_unlock(&tpg->acl_node_mutex);
return found;
}
EXPORT_SYMBOL(target_tpg_has_node_acl);
struct se_node_acl *core_tpg_check_initiator_node_acl(
struct se_portal_group *tpg,
unsigned char *initiatorname)
{
struct se_node_acl *acl;
acl = core_tpg_get_initiator_node_acl(tpg, initiatorname);
if (acl)
return acl;
if (!tpg->se_tpg_tfo->tpg_check_demo_mode(tpg))
return NULL;
acl = target_alloc_node_acl(tpg, initiatorname);
if (!acl)
return NULL;
/*
* When allocating a dynamically generated node_acl, go ahead
* and take the extra kref now before returning to the fabric
* driver caller.
*
* Note this reference will be released at session shutdown
* time within transport_free_session() code.
*/
kref_get(&acl->acl_kref);
acl->dynamic_node_acl = 1;
/*
* Here we only create demo-mode MappedLUNs from the active
* TPG LUNs if the fabric is not explicitly asking for
* tpg_check_demo_mode_login_only() == 1.
*/
if ((tpg->se_tpg_tfo->tpg_check_demo_mode_login_only == NULL) ||
(tpg->se_tpg_tfo->tpg_check_demo_mode_login_only(tpg) != 1))
core_tpg_add_node_to_devs(acl, tpg, NULL);
target_add_node_acl(acl);
return acl;
}
EXPORT_SYMBOL(core_tpg_check_initiator_node_acl);
void core_tpg_wait_for_nacl_pr_ref(struct se_node_acl *nacl)
{
while (atomic_read(&nacl->acl_pr_ref_count) != 0)
cpu_relax();
}
struct se_node_acl *core_tpg_add_initiator_node_acl(
struct se_portal_group *tpg,
const char *initiatorname)
{
struct se_node_acl *acl;
mutex_lock(&tpg->acl_node_mutex);
acl = __core_tpg_get_initiator_node_acl(tpg, initiatorname);
if (acl) {
if (acl->dynamic_node_acl) {
acl->dynamic_node_acl = 0;
pr_debug("%s_TPG[%u] - Replacing dynamic ACL"
" for %s\n", tpg->se_tpg_tfo->get_fabric_name(),
tpg->se_tpg_tfo->tpg_get_tag(tpg), initiatorname);
mutex_unlock(&tpg->acl_node_mutex);
return acl;
}
pr_err("ACL entry for %s Initiator"
" Node %s already exists for TPG %u, ignoring"
" request.\n", tpg->se_tpg_tfo->get_fabric_name(),
initiatorname, tpg->se_tpg_tfo->tpg_get_tag(tpg));
mutex_unlock(&tpg->acl_node_mutex);
return ERR_PTR(-EEXIST);
}
mutex_unlock(&tpg->acl_node_mutex);
acl = target_alloc_node_acl(tpg, initiatorname);
if (!acl)
return ERR_PTR(-ENOMEM);
target_add_node_acl(acl);
return acl;
}
static void target_shutdown_sessions(struct se_node_acl *acl)
{
struct se_session *sess;
unsigned long flags;
restart:
spin_lock_irqsave(&acl->nacl_sess_lock, flags);
list_for_each_entry(sess, &acl->acl_sess_list, sess_acl_list) {
if (sess->sess_tearing_down)
continue;
list_del_init(&sess->sess_acl_list);
spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
if (acl->se_tpg->se_tpg_tfo->close_session)
acl->se_tpg->se_tpg_tfo->close_session(sess);
goto restart;
}
spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
}
void core_tpg_del_initiator_node_acl(struct se_node_acl *acl)
{
struct se_portal_group *tpg = acl->se_tpg;
mutex_lock(&tpg->acl_node_mutex);
if (acl->dynamic_node_acl)
acl->dynamic_node_acl = 0;
list_del(&acl->acl_list);
mutex_unlock(&tpg->acl_node_mutex);
target_shutdown_sessions(acl);
target_put_nacl(acl);
/*
* Wait for last target_put_nacl() to complete in target_complete_nacl()
* for active fabric session transport_deregister_session() callbacks.
*/
wait_for_completion(&acl->acl_free_comp);
core_tpg_wait_for_nacl_pr_ref(acl);
core_free_device_list_for_node(acl, tpg);
pr_debug("%s_TPG[%hu] - Deleted ACL with TCQ Depth: %d for %s"
" Initiator Node: %s\n", tpg->se_tpg_tfo->get_fabric_name(),
tpg->se_tpg_tfo->tpg_get_tag(tpg), acl->queue_depth,
tpg->se_tpg_tfo->get_fabric_name(), acl->initiatorname);
kfree(acl);
}
/* core_tpg_set_initiator_node_queue_depth():
*
*
*/
int core_tpg_set_initiator_node_queue_depth(
struct se_node_acl *acl,
u32 queue_depth)
{
struct se_portal_group *tpg = acl->se_tpg;
/*
* User has requested to change the queue depth for a Initiator Node.
* Change the value in the Node's struct se_node_acl, and call
* target_set_nacl_queue_depth() to set the new queue depth.
*/
target_set_nacl_queue_depth(tpg, acl, queue_depth);
/*
* Shutdown all pending sessions to force session reinstatement.
*/
target_shutdown_sessions(acl);
pr_debug("Successfully changed queue depth to: %d for Initiator"
" Node: %s on %s Target Portal Group: %u\n", acl->queue_depth,
acl->initiatorname, tpg->se_tpg_tfo->get_fabric_name(),
tpg->se_tpg_tfo->tpg_get_tag(tpg));
return 0;
}
EXPORT_SYMBOL(core_tpg_set_initiator_node_queue_depth);
/* core_tpg_set_initiator_node_tag():
*
* Initiator nodeacl tags are not used internally, but may be used by
* userspace to emulate aliases or groups.
* Returns length of newly-set tag or -EINVAL.
*/
int core_tpg_set_initiator_node_tag(
struct se_portal_group *tpg,
struct se_node_acl *acl,
const char *new_tag)
{
if (strlen(new_tag) >= MAX_ACL_TAG_SIZE)
return -EINVAL;
if (!strncmp("NULL", new_tag, 4)) {
acl->acl_tag[0] = '\0';
return 0;
}
return snprintf(acl->acl_tag, MAX_ACL_TAG_SIZE, "%s", new_tag);
}
EXPORT_SYMBOL(core_tpg_set_initiator_node_tag);
static void core_tpg_lun_ref_release(struct percpu_ref *ref)
{
struct se_lun *lun = container_of(ref, struct se_lun, lun_ref);
complete(&lun->lun_shutdown_comp);
}
/* Does not change se_wwn->priv. */
int core_tpg_register(
struct se_wwn *se_wwn,
struct se_portal_group *se_tpg,
int proto_id)
{
int ret;
if (!se_tpg)
return -EINVAL;
/*
* For the typical case where core_tpg_register() is called by a
* fabric driver from target_core_fabric_ops->fabric_make_tpg()
* configfs context, use the original tf_ops pointer already saved
* by target-core in target_fabric_make_wwn().
*
* Otherwise, for special cases like iscsi-target discovery TPGs
* the caller is responsible for setting ->se_tpg_tfo ahead of
* calling core_tpg_register().
*/
if (se_wwn)
se_tpg->se_tpg_tfo = se_wwn->wwn_tf->tf_ops;
if (!se_tpg->se_tpg_tfo) {
pr_err("Unable to locate se_tpg->se_tpg_tfo pointer\n");
return -EINVAL;
}
INIT_HLIST_HEAD(&se_tpg->tpg_lun_hlist);
se_tpg->proto_id = proto_id;
se_tpg->se_tpg_wwn = se_wwn;
atomic_set(&se_tpg->tpg_pr_ref_count, 0);
INIT_LIST_HEAD(&se_tpg->acl_node_list);
INIT_LIST_HEAD(&se_tpg->se_tpg_node);
INIT_LIST_HEAD(&se_tpg->tpg_sess_list);
spin_lock_init(&se_tpg->session_lock);
mutex_init(&se_tpg->tpg_lun_mutex);
mutex_init(&se_tpg->acl_node_mutex);
if (se_tpg->proto_id >= 0) {
se_tpg->tpg_virt_lun0 = core_tpg_alloc_lun(se_tpg, 0);
if (IS_ERR(se_tpg->tpg_virt_lun0))
return PTR_ERR(se_tpg->tpg_virt_lun0);
ret = core_tpg_add_lun(se_tpg, se_tpg->tpg_virt_lun0,
true, g_lun0_dev);
if (ret < 0) {
kfree(se_tpg->tpg_virt_lun0);
return ret;
}
}
spin_lock_bh(&tpg_lock);
list_add_tail(&se_tpg->se_tpg_node, &tpg_list);
spin_unlock_bh(&tpg_lock);
pr_debug("TARGET_CORE[%s]: Allocated portal_group for endpoint: %s, "
"Proto: %d, Portal Tag: %u\n", se_tpg->se_tpg_tfo->get_fabric_name(),
se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg) ?
se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg) : NULL,
se_tpg->proto_id, se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
return 0;
}
EXPORT_SYMBOL(core_tpg_register);
int core_tpg_deregister(struct se_portal_group *se_tpg)
{
const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
struct se_node_acl *nacl, *nacl_tmp;
LIST_HEAD(node_list);
pr_debug("TARGET_CORE[%s]: Deallocating portal_group for endpoint: %s, "
"Proto: %d, Portal Tag: %u\n", tfo->get_fabric_name(),
tfo->tpg_get_wwn(se_tpg) ? tfo->tpg_get_wwn(se_tpg) : NULL,
se_tpg->proto_id, tfo->tpg_get_tag(se_tpg));
spin_lock_bh(&tpg_lock);
list_del(&se_tpg->se_tpg_node);
spin_unlock_bh(&tpg_lock);
while (atomic_read(&se_tpg->tpg_pr_ref_count) != 0)
cpu_relax();
mutex_lock(&se_tpg->acl_node_mutex);
list_splice_init(&se_tpg->acl_node_list, &node_list);
mutex_unlock(&se_tpg->acl_node_mutex);
/*
* Release any remaining demo-mode generated se_node_acl that have
* not been released because of TFO->tpg_check_demo_mode_cache() == 1
* in transport_deregister_session().
*/
list_for_each_entry_safe(nacl, nacl_tmp, &node_list, acl_list) {
list_del(&nacl->acl_list);
core_tpg_wait_for_nacl_pr_ref(nacl);
core_free_device_list_for_node(nacl, se_tpg);
kfree(nacl);
}
if (se_tpg->proto_id >= 0) {
core_tpg_remove_lun(se_tpg, se_tpg->tpg_virt_lun0);
kfree_rcu(se_tpg->tpg_virt_lun0, rcu_head);
}
return 0;
}
EXPORT_SYMBOL(core_tpg_deregister);
struct se_lun *core_tpg_alloc_lun(
struct se_portal_group *tpg,
u64 unpacked_lun)
{
struct se_lun *lun;
lun = kzalloc(sizeof(*lun), GFP_KERNEL);
if (!lun) {
pr_err("Unable to allocate se_lun memory\n");
return ERR_PTR(-ENOMEM);
}
lun->unpacked_lun = unpacked_lun;
lun->lun_link_magic = SE_LUN_LINK_MAGIC;
atomic_set(&lun->lun_acl_count, 0);
init_completion(&lun->lun_ref_comp);
init_completion(&lun->lun_shutdown_comp);
INIT_LIST_HEAD(&lun->lun_deve_list);
INIT_LIST_HEAD(&lun->lun_dev_link);
atomic_set(&lun->lun_tg_pt_secondary_offline, 0);
spin_lock_init(&lun->lun_deve_lock);
mutex_init(&lun->lun_tg_pt_md_mutex);
INIT_LIST_HEAD(&lun->lun_tg_pt_gp_link);
spin_lock_init(&lun->lun_tg_pt_gp_lock);
lun->lun_tpg = tpg;
return lun;
}
int core_tpg_add_lun(
struct se_portal_group *tpg,
struct se_lun *lun,
bool lun_access_ro,
struct se_device *dev)
{
int ret;
ret = percpu_ref_init(&lun->lun_ref, core_tpg_lun_ref_release, 0,
GFP_KERNEL);
if (ret < 0)
goto out;
ret = core_alloc_rtpi(lun, dev);
if (ret)
goto out_kill_ref;
if (!(dev->transport->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);
mutex_lock(&tpg->tpg_lun_mutex);
spin_lock(&dev->se_port_lock);
lun->lun_index = dev->dev_index;
rcu_assign_pointer(lun->lun_se_dev, dev);
dev->export_count++;
list_add_tail(&lun->lun_dev_link, &dev->dev_sep_list);
spin_unlock(&dev->se_port_lock);
if (dev->dev_flags & DF_READ_ONLY)
lun->lun_access_ro = true;
else
lun->lun_access_ro = lun_access_ro;
if (!(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
hlist_add_head_rcu(&lun->link, &tpg->tpg_lun_hlist);
mutex_unlock(&tpg->tpg_lun_mutex);
return 0;
out_kill_ref:
percpu_ref_exit(&lun->lun_ref);
out:
return ret;
}
void core_tpg_remove_lun(
struct se_portal_group *tpg,
struct se_lun *lun)
{
/*
* rcu_dereference_raw protected by se_lun->lun_group symlink
* reference to se_device->dev_group.
*/
struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
core_clear_lun_from_tpg(lun, tpg);
/*
* Wait for any active I/O references to percpu se_lun->lun_ref to
* be released. Also, se_lun->lun_ref is now used by PR and ALUA
* logic when referencing a remote target port during ALL_TGT_PT=1
* and generating UNIT_ATTENTIONs for ALUA access state transition.
*/
transport_clear_lun_ref(lun);
mutex_lock(&tpg->tpg_lun_mutex);
if (lun->lun_se_dev) {
target_detach_tg_pt_gp(lun);
spin_lock(&dev->se_port_lock);
list_del(&lun->lun_dev_link);
dev->export_count--;
rcu_assign_pointer(lun->lun_se_dev, NULL);
spin_unlock(&dev->se_port_lock);
}
if (!(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
hlist_del_rcu(&lun->link);
mutex_unlock(&tpg->tpg_lun_mutex);
percpu_ref_exit(&lun->lun_ref);
}