linux/drivers/target/target_core_tpg.c
Linus Torvalds 5c755fe142 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target updates from Nicholas Bellinger:
 "It's been a busy development cycle for target-core in a number of
  different areas.

  The fabric API usage for se_node_acl allocation is now within
  target-core code, dropping the external API callers for all fabric
  drivers tree-wide.

  There is a new conversion to RCU hlists for se_node_acl and
  se_portal_group LUN mappings, that turns fast-past LUN lookup into a
  completely lockless code-path.  It also removes the original
  hard-coded limitation of 256 LUNs per fabric endpoint.

  The configfs attributes for backends can now be shared between core
  and driver code, allowing existing drivers to use common code while
  still allowing flexibility for new backend provided attributes.

  The highlights include:

   - Merge sbc_verify_dif_* into common code (sagi)
   - Remove iscsi-target support for obsolete IFMarker/OFMarker
     (Christophe Vu-Brugier)
   - Add bidi support in target/user backend (ilias + vangelis + agover)
   - Move se_node_acl allocation into target-core code (hch)
   - Add crc_t10dif_update common helper (akinobu + mkp)
   - Handle target-core odd SGL mapping for data transfer memory
     (akinobu)
   - Move transport ID handling into target-core (hch)
   - Move task tag into struct se_cmd + support 64-bit tags (bart)
   - Convert se_node_acl->device_list[] to RCU hlist (nab + hch +
     paulmck)
   - Convert se_portal_group->tpg_lun_list[] to RCU hlist (nab + hch +
     paulmck)
   - Simplify target backend driver registration (hch)
   - Consolidate + simplify target backend attribute implementations
     (hch + nab)
   - Subsume se_port + t10_alua_tg_pt_gp_member into se_lun (hch)
   - Drop lun_sep_lock for se_lun->lun_se_dev RCU usage (hch + nab)
   - Drop unnecessary core_tpg_register TFO parameter (nab)
   - Use 64-bit LUNs tree-wide (hannes)
   - Drop left-over TARGET_MAX_LUNS_PER_TRANSPORT limit (hannes)"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (76 commits)
  target: Bump core version to v5.0
  target: remove target_core_configfs.h
  target: remove unused TARGET_CORE_CONFIG_ROOT define
  target: consolidate version defines
  target: implement WRITE_SAME with UNMAP bit using ->execute_unmap
  target: simplify UNMAP handling
  target: replace se_cmd->execute_rw with a protocol_data field
  target/user: Fix inconsistent kmap_atomic/kunmap_atomic
  target: Send UA when changing LUN inventory
  target: Send UA upon LUN RESET tmr completion
  target: Send UA on ALUA target port group change
  target: Convert se_lun->lun_deve_lock to normal spinlock
  target: use 'se_dev_entry' when allocating UAs
  target: Remove 'ua_nacl' pointer from se_ua structure
  target_core_alua: Correct UA handling when switching states
  xen-scsiback: Fix compile warning for 64-bit LUN
  target: Remove TARGET_MAX_LUNS_PER_TRANSPORT
  target: use 64-bit LUNs
  target: Drop duplicate + unused se_dev_check_wce
  target: Drop unnecessary core_tpg_register TFO parameter
  ...
2015-07-04 14:13:43 -07:00

702 lines
19 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"
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;
mutex_lock(&tpg->acl_node_mutex);
acl = __core_tpg_get_initiator_node_acl(tpg, initiatorname);
mutex_unlock(&tpg->acl_node_mutex);
return acl;
}
EXPORT_SYMBOL(core_tpg_get_initiator_node_acl);
/* 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)
{
u32 lun_access = 0;
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 = TRANSPORT_LUNFLAGS_READ_WRITE;
} 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 = TRANSPORT_LUNFLAGS_READ_ONLY;
else
lun_access = TRANSPORT_LUNFLAGS_READ_WRITE;
}
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 == TRANSPORT_LUNFLAGS_READ_WRITE) ?
"READ-WRITE" : "READ-ONLY");
core_enable_device_list_for_node(lun, NULL, lun->unpacked_lun,
lun_access, 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);
}
/* core_set_queue_depth_for_node():
*
*
*/
static int core_set_queue_depth_for_node(
struct se_portal_group *tpg,
struct se_node_acl *acl)
{
if (!acl->queue_depth) {
pr_err("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;
}
return 0;
}
static struct se_node_acl *target_alloc_node_acl(struct se_portal_group *tpg,
const unsigned char *initiatorname)
{
struct se_node_acl *acl;
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)
acl->queue_depth = tpg->se_tpg_tfo->tpg_get_default_depth(tpg);
else
acl->queue_depth = 1;
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);
if (core_set_queue_depth_for_node(tpg, acl) < 0)
goto out_free_acl;
return acl;
out_free_acl:
kfree(acl);
return NULL;
}
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);
tpg->num_node_acls++;
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);
}
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;
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;
}
void core_tpg_del_initiator_node_acl(struct se_node_acl *acl)
{
struct se_portal_group *tpg = acl->se_tpg;
LIST_HEAD(sess_list);
struct se_session *sess, *sess_tmp;
unsigned long flags;
int rc;
mutex_lock(&tpg->acl_node_mutex);
if (acl->dynamic_node_acl) {
acl->dynamic_node_acl = 0;
}
list_del(&acl->acl_list);
tpg->num_node_acls--;
mutex_unlock(&tpg->acl_node_mutex);
spin_lock_irqsave(&acl->nacl_sess_lock, flags);
acl->acl_stop = 1;
list_for_each_entry_safe(sess, sess_tmp, &acl->acl_sess_list,
sess_acl_list) {
if (sess->sess_tearing_down != 0)
continue;
target_get_session(sess);
list_move(&sess->sess_acl_list, &sess_list);
}
spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
list_for_each_entry_safe(sess, sess_tmp, &sess_list, sess_acl_list) {
list_del(&sess->sess_acl_list);
rc = tpg->se_tpg_tfo->shutdown_session(sess);
target_put_session(sess);
if (!rc)
continue;
target_put_session(sess);
}
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_portal_group *tpg,
unsigned char *initiatorname,
u32 queue_depth,
int force)
{
struct se_session *sess, *init_sess = NULL;
struct se_node_acl *acl;
unsigned long flags;
int dynamic_acl = 0;
mutex_lock(&tpg->acl_node_mutex);
acl = __core_tpg_get_initiator_node_acl(tpg, initiatorname);
if (!acl) {
pr_err("Access Control List entry for %s Initiator"
" Node %s does not exists for TPG %hu, 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 -ENODEV;
}
if (acl->dynamic_node_acl) {
acl->dynamic_node_acl = 0;
dynamic_acl = 1;
}
mutex_unlock(&tpg->acl_node_mutex);
spin_lock_irqsave(&tpg->session_lock, flags);
list_for_each_entry(sess, &tpg->tpg_sess_list, sess_list) {
if (sess->se_node_acl != acl)
continue;
if (!force) {
pr_err("Unable to change queue depth for %s"
" Initiator Node: %s while session is"
" operational. To forcefully change the queue"
" depth and force session reinstatement"
" use the \"force=1\" parameter.\n",
tpg->se_tpg_tfo->get_fabric_name(), initiatorname);
spin_unlock_irqrestore(&tpg->session_lock, flags);
mutex_lock(&tpg->acl_node_mutex);
if (dynamic_acl)
acl->dynamic_node_acl = 1;
mutex_unlock(&tpg->acl_node_mutex);
return -EEXIST;
}
/*
* Determine if the session needs to be closed by our context.
*/
if (!tpg->se_tpg_tfo->shutdown_session(sess))
continue;
init_sess = sess;
break;
}
/*
* 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
* core_set_queue_depth_for_node() to add the requested queue depth.
*
* Finally call tpg->se_tpg_tfo->close_session() to force session
* reinstatement to occur if there is an active session for the
* $FABRIC_MOD Initiator Node in question.
*/
acl->queue_depth = queue_depth;
if (core_set_queue_depth_for_node(tpg, acl) < 0) {
spin_unlock_irqrestore(&tpg->session_lock, flags);
/*
* Force session reinstatement if
* core_set_queue_depth_for_node() failed, because we assume
* the $FABRIC_MOD has already the set session reinstatement
* bit from tpg->se_tpg_tfo->shutdown_session() called above.
*/
if (init_sess)
tpg->se_tpg_tfo->close_session(init_sess);
mutex_lock(&tpg->acl_node_mutex);
if (dynamic_acl)
acl->dynamic_node_acl = 1;
mutex_unlock(&tpg->acl_node_mutex);
return -EINVAL;
}
spin_unlock_irqrestore(&tpg->session_lock, flags);
/*
* If the $FABRIC_MOD session for the Initiator Node ACL exists,
* forcefully shutdown the $FABRIC_MOD session/nexus.
*/
if (init_sess)
tpg->se_tpg_tfo->close_session(init_sess);
pr_debug("Successfully changed queue depth to: %d for Initiator"
" Node: %s on %s Target Portal Group: %u\n", queue_depth,
initiatorname, tpg->se_tpg_tfo->get_fabric_name(),
tpg->se_tpg_tfo->tpg_get_tag(tpg));
mutex_lock(&tpg->acl_node_mutex);
if (dynamic_acl)
acl->dynamic_node_acl = 1;
mutex_unlock(&tpg->acl_node_mutex);
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_ref_comp);
}
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,
TRANSPORT_LUNFLAGS_READ_ONLY, 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);
se_tpg->num_node_acls--;
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_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,
u32 lun_access,
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) &&
!(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);
lun->lun_access = lun_access;
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);
}