[RFCv3 04/21] tcm: Add SPC-4 explict and implict Asymmetric Logical Unit Access (ALUA)

From: Nicholas A. Bellinger
Date: Mon Oct 18 2010 - 18:37:01 EST


From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>

This patch adds explict (via SET_TARGET_PORT_GROUPS) implict (via ConfigFS) ALUA support
supporting all primary and secondary access states. This also supports both the
Logical Unit and Target Port Groups abstractions defined by SPC-4

It also include support for writing ALUA metadata to /var/target/alua for saving Primary/Secondary
access states and status across target power loss, reboots, etc.

This is a complete implemention of SPC-4 ALUA, for more information please see:

http://www.linux-iscsi.org/index.php/ALUA

Signed-off-by: Nicholas A. Bellinger <nab@xxxxxxxxxxxxxxx>
---
drivers/target/target_core_alua.c | 1993 +++++++++++++++++++++++++++++++++++++
drivers/target/target_core_alua.h | 142 +++
2 files changed, 2135 insertions(+), 0 deletions(-)
create mode 100644 drivers/target/target_core_alua.c
create mode 100644 drivers/target/target_core_alua.h

diff --git a/drivers/target/target_core_alua.c b/drivers/target/target_core_alua.c
new file mode 100644
index 0000000..32f6fb6
--- /dev/null
+++ b/drivers/target/target_core_alua.c
@@ -0,0 +1,1993 @@
+/*******************************************************************************
+ * Filename: target_core_alua.c
+ *
+ * This file contains SPC-3 compliant asymmetric logical unit assigntment (ALUA)
+ *
+ * Copyright (c) 2009-2010 Rising Tide Systems
+ * Copyright (c) 2009-2010 Linux-iSCSI.org
+ *
+ * Nicholas A. Bellinger <nab@xxxxxxxxxx>
+ *
+ * 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/version.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/configfs.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+
+#include <target/target_core_base.h>
+#include <target/target_core_device.h>
+#include <target/target_core_transport.h>
+#include <target/target_core_fabric_ops.h>
+#include <target/target_core_configfs.h>
+
+#include "target_core_alua.h"
+#include "target_core_hba.h"
+#include "target_core_ua.h"
+
+/*
+ * REPORT_TARGET_PORT_GROUPS
+ *
+ * See spc4r17 section 6.27
+ */
+int core_emulate_report_target_port_groups(struct se_cmd *cmd)
+{
+ struct se_subsystem_dev *su_dev = SE_DEV(cmd)->se_sub_dev;
+ struct se_port *port;
+ struct t10_alua_tg_pt_gp *tg_pt_gp;
+ struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
+ unsigned char *buf = (unsigned char *)T_TASK(cmd)->t_task_buf;
+ u32 rd_len = 0, off = 4; /* Skip over RESERVED area to first
+ Target port group descriptor */
+
+ spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ list_for_each_entry(tg_pt_gp, &T10_ALUA(su_dev)->tg_pt_gps_list,
+ tg_pt_gp_list) {
+ /*
+ * PREF: Preferred target port bit, determine if this
+ * bit should be set for port group.
+ */
+ if (tg_pt_gp->tg_pt_gp_pref)
+ buf[off] = 0x80;
+ /*
+ * Set the ASYMMETRIC ACCESS State
+ */
+ buf[off++] |= (atomic_read(
+ &tg_pt_gp->tg_pt_gp_alua_access_state) & 0xff);
+ /*
+ * Set supported ASYMMETRIC ACCESS State bits
+ */
+ buf[off] = 0x80; /* T_SUP */
+ buf[off] |= 0x40; /* O_SUP */
+ buf[off] |= 0x8; /* U_SUP */
+ buf[off] |= 0x4; /* S_SUP */
+ buf[off] |= 0x2; /* AN_SUP */
+ buf[off++] |= 0x1; /* AO_SUP */
+ /*
+ * TARGET PORT GROUP
+ */
+ buf[off++] = ((tg_pt_gp->tg_pt_gp_id >> 8) & 0xff);
+ buf[off++] = (tg_pt_gp->tg_pt_gp_id & 0xff);
+
+ off++; /* Skip over Reserved */
+ /*
+ * STATUS CODE
+ */
+ buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
+ /*
+ * Vendor Specific field
+ */
+ buf[off++] = 0x00;
+ /*
+ * TARGET PORT COUNT
+ */
+ buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
+ rd_len += 8;
+
+ spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+ list_for_each_entry(tg_pt_gp_mem, &tg_pt_gp->tg_pt_gp_mem_list,
+ tg_pt_gp_mem_list) {
+ port = tg_pt_gp_mem->tg_pt;
+ /*
+ * Start Target Port descriptor format
+ *
+ * See spc4r17 section 6.2.7 Table 247
+ */
+ off += 2; /* Skip over Obsolete */
+ /*
+ * Set RELATIVE TARGET PORT IDENTIFIER
+ */
+ buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
+ buf[off++] = (port->sep_rtpi & 0xff);
+ rd_len += 4;
+ }
+ spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+ }
+ spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ /*
+ * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
+ */
+ buf[0] = ((rd_len >> 24) & 0xff);
+ buf[1] = ((rd_len >> 16) & 0xff);
+ buf[2] = ((rd_len >> 8) & 0xff);
+ buf[3] = (rd_len & 0xff);
+
+ return 0;
+}
+
+/*
+ * SET_TARGET_PORT_GROUPS for explict ALUA operation.
+ *
+ * See spc4r17 section 6.35
+ */
+int core_emulate_set_target_port_groups(struct se_cmd *cmd)
+{
+ struct se_device *dev = SE_DEV(cmd);
+ struct se_subsystem_dev *su_dev = SE_DEV(cmd)->se_sub_dev;
+ struct se_port *port, *l_port = SE_LUN(cmd)->lun_sep;
+ struct se_node_acl *nacl = SE_SESS(cmd)->se_node_acl;
+ struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
+ struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *l_tg_pt_gp_mem;
+ unsigned char *buf = (unsigned char *)T_TASK(cmd)->t_task_buf;
+ unsigned char *ptr = &buf[4]; /* Skip over RESERVED area in header */
+ u32 len = 4; /* Skip over RESERVED area in header */
+ int alua_access_state, primary = 0, rc;
+ u16 tg_pt_id, rtpi;
+
+ if (!(l_port))
+ return PYX_TRANSPORT_LU_COMM_FAILURE;
+ /*
+ * Determine if explict ALUA via SET_TARGET_PORT_GROUPS is allowed
+ * for the local tg_pt_gp.
+ */
+ l_tg_pt_gp_mem = l_port->sep_alua_tg_pt_gp_mem;
+ if (!(l_tg_pt_gp_mem)) {
+ printk(KERN_ERR "Unable to access l_port->sep_alua_tg_pt_gp_mem\n");
+ return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
+ }
+ spin_lock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
+ l_tg_pt_gp = l_tg_pt_gp_mem->tg_pt_gp;
+ if (!(l_tg_pt_gp)) {
+ spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
+ printk(KERN_ERR "Unable to access *l_tg_pt_gp_mem->tg_pt_gp\n");
+ return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
+ }
+ rc = (l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA);
+ spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
+
+ if (!(rc)) {
+ printk(KERN_INFO "Unable to process SET_TARGET_PORT_GROUPS"
+ " while TPGS_EXPLICT_ALUA is disabled\n");
+ return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
+ }
+
+ while (len < cmd->data_length) {
+ alua_access_state = (ptr[0] & 0x0f);
+ /*
+ * Check the received ALUA access state, and determine if
+ * the state is a primary or secondary target port asymmetric
+ * access state.
+ */
+ rc = core_alua_check_transition(alua_access_state, &primary);
+ if (rc != 0) {
+ /*
+ * If the SET TARGET PORT GROUPS attempts to establish
+ * an invalid combination of target port asymmetric
+ * access states or attempts to establish an
+ * unsupported target port asymmetric access state,
+ * then the command shall be terminated with CHECK
+ * CONDITION status, with the sense key set to ILLEGAL
+ * REQUEST, and the additional sense code set to INVALID
+ * FIELD IN PARAMETER LIST.
+ */
+ return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
+ }
+ rc = -1;
+ /*
+ * If the ASYMMETRIC ACCESS STATE field (see table 267)
+ * specifies a primary target port asymmetric access state,
+ * then the TARGET PORT GROUP OR TARGET PORT field specifies
+ * a primary target port group for which the primary target
+ * port asymmetric access state shall be changed. If the
+ * ASYMMETRIC ACCESS STATE field specifies a secondary target
+ * port asymmetric access state, then the TARGET PORT GROUP OR
+ * TARGET PORT field specifies the relative target port
+ * identifier (see 3.1.120) of the target port for which the
+ * secondary target port asymmetric access state shall be
+ * changed.
+ */
+ if (primary) {
+ tg_pt_id = ((ptr[2] << 8) & 0xff);
+ tg_pt_id |= (ptr[3] & 0xff);
+ /*
+ * Locate the matching target port group ID from
+ * the global tg_pt_gp list
+ */
+ spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ list_for_each_entry(tg_pt_gp,
+ &T10_ALUA(su_dev)->tg_pt_gps_list,
+ tg_pt_gp_list) {
+ if (!(tg_pt_gp->tg_pt_gp_valid_id))
+ continue;
+
+ if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
+ continue;
+
+ atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
+ smp_mb__after_atomic_inc();
+ spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+
+ rc = core_alua_do_port_transition(tg_pt_gp,
+ dev, l_port, nacl,
+ alua_access_state, 1);
+
+ spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
+ smp_mb__after_atomic_dec();
+ break;
+ }
+ spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ /*
+ * If not matching target port group ID can be located
+ * throw an exception with ASCQ: INVALID_PARAMETER_LIST
+ */
+ if (rc != 0)
+ return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
+ } else {
+ /*
+ * Extact the RELATIVE TARGET PORT IDENTIFIER to identify
+ * the Target Port in question for the the incoming
+ * SET_TARGET_PORT_GROUPS op.
+ */
+ rtpi = ((ptr[2] << 8) & 0xff);
+ rtpi |= (ptr[3] & 0xff);
+ /*
+ * Locate the matching relative target port identifer
+ * for the struct se_device storage object.
+ */
+ spin_lock(&dev->se_port_lock);
+ list_for_each_entry(port, &dev->dev_sep_list,
+ sep_list) {
+ if (port->sep_rtpi != rtpi)
+ continue;
+
+ tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
+ spin_unlock(&dev->se_port_lock);
+
+ rc = core_alua_set_tg_pt_secondary_state(
+ tg_pt_gp_mem, port, 1, 1);
+
+ spin_lock(&dev->se_port_lock);
+ break;
+ }
+ spin_unlock(&dev->se_port_lock);
+ /*
+ * If not matching relative target port identifier can
+ * be located, throw an exception with ASCQ:
+ * INVALID_PARAMETER_LIST
+ */
+ if (rc != 0)
+ return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
+ }
+
+ ptr += 4;
+ len += 4;
+ }
+
+ return 0;
+}
+
+static inline int core_alua_state_nonoptimized(
+ struct se_cmd *cmd,
+ unsigned char *cdb,
+ int nonop_delay_msecs,
+ u8 *alua_ascq)
+{
+ /*
+ * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
+ * later to determine if processing of this cmd needs to be
+ * temporarily delayed for the Active/NonOptimized primary access state.
+ */
+ cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
+ cmd->alua_nonop_delay = nonop_delay_msecs;
+ return 0;
+}
+
+static inline int core_alua_state_standby(
+ struct se_cmd *cmd,
+ unsigned char *cdb,
+ u8 *alua_ascq)
+{
+ /*
+ * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
+ * spc4r17 section 5.9.2.4.4
+ */
+ switch (cdb[0]) {
+ case INQUIRY:
+ case LOG_SELECT:
+ case LOG_SENSE:
+ case MODE_SELECT:
+ case MODE_SENSE:
+ case REPORT_LUNS:
+ case RECEIVE_DIAGNOSTIC:
+ case SEND_DIAGNOSTIC:
+ case MAINTENANCE_IN:
+ switch (cdb[1]) {
+ case MI_REPORT_TARGET_PGS:
+ return 0;
+ default:
+ *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
+ return 1;
+ }
+ case MAINTENANCE_OUT:
+ switch (cdb[1]) {
+ case MO_SET_TARGET_PGS:
+ return 0;
+ default:
+ *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
+ return 1;
+ }
+ case REQUEST_SENSE:
+ case PERSISTENT_RESERVE_IN:
+ case PERSISTENT_RESERVE_OUT:
+ case READ_BUFFER:
+ case WRITE_BUFFER:
+ return 0;
+ default:
+ *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
+ return 1;
+ }
+
+ return 0;
+}
+
+static inline int core_alua_state_unavailable(
+ struct se_cmd *cmd,
+ unsigned char *cdb,
+ u8 *alua_ascq)
+{
+ /*
+ * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
+ * spc4r17 section 5.9.2.4.5
+ */
+ switch (cdb[0]) {
+ case INQUIRY:
+ case REPORT_LUNS:
+ case MAINTENANCE_IN:
+ switch (cdb[1]) {
+ case MI_REPORT_TARGET_PGS:
+ return 0;
+ default:
+ *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
+ return 1;
+ }
+ case MAINTENANCE_OUT:
+ switch (cdb[1]) {
+ case MO_SET_TARGET_PGS:
+ return 0;
+ default:
+ *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
+ return 1;
+ }
+ case REQUEST_SENSE:
+ case READ_BUFFER:
+ case WRITE_BUFFER:
+ return 0;
+ default:
+ *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
+ return 1;
+ }
+
+ return 0;
+}
+
+static inline int core_alua_state_transition(
+ struct se_cmd *cmd,
+ unsigned char *cdb,
+ u8 *alua_ascq)
+{
+ /*
+ * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITIO as defined by
+ * spc4r17 section 5.9.2.5
+ */
+ switch (cdb[0]) {
+ case INQUIRY:
+ case REPORT_LUNS:
+ case MAINTENANCE_IN:
+ switch (cdb[1]) {
+ case MI_REPORT_TARGET_PGS:
+ return 0;
+ default:
+ *alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
+ return 1;
+ }
+ case REQUEST_SENSE:
+ case READ_BUFFER:
+ case WRITE_BUFFER:
+ return 0;
+ default:
+ *alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
+ return 1;
+ }
+
+ return 0;
+}
+
+/*
+ * Used for alua_type SPC_ALUA_PASSTHROUGH and SPC2_ALUA_DISABLED
+ * in transport_cmd_sequencer(). This function is assigned to
+ * struct t10_alua *->state_check() in core_setup_alua()
+ */
+int core_alua_state_check_nop(
+ struct se_cmd *cmd,
+ unsigned char *cdb,
+ u8 *alua_ascq)
+{
+ return 0;
+}
+
+/*
+ * Used for alua_type SPC3_ALUA_EMULATED in transport_cmd_sequencer().
+ * This function is assigned to struct t10_alua *->state_check() in
+ * core_setup_alua()
+ *
+ * Also, this function can return three different return codes to
+ * signal transport_generic_cmd_sequencer()
+ *
+ * return 1: Is used to signal LUN not accecsable, and TGCS_CHECK_CONDITION_NOT_READY
+ * return 0: Used to signal success
+ * reutrn -1: Used to signal failure, and TGCS_INVALID_CDB_FIELD
+ */
+int core_alua_state_check(
+ struct se_cmd *cmd,
+ unsigned char *cdb,
+ u8 *alua_ascq)
+{
+ struct se_lun *lun = SE_LUN(cmd);
+ struct se_port *port = lun->lun_sep;
+ struct t10_alua_tg_pt_gp *tg_pt_gp;
+ struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
+ int out_alua_state, nonop_delay_msecs;
+
+ if (!(port))
+ return 0;
+ /*
+ * First, check for a struct se_port specific secondary ALUA target port
+ * access state: OFFLINE
+ */
+ if (atomic_read(&port->sep_tg_pt_secondary_offline)) {
+ *alua_ascq = ASCQ_04H_ALUA_OFFLINE;
+ printk(KERN_INFO "ALUA: Got secondary offline status for local"
+ " target port\n");
+ *alua_ascq = ASCQ_04H_ALUA_OFFLINE;
+ return 1;
+ }
+ /*
+ * Second, obtain the struct t10_alua_tg_pt_gp_member pointer to the
+ * ALUA target port group, to obtain current ALUA access state.
+ * Otherwise look for the underlying struct se_device association with
+ * a ALUA logical unit group.
+ */
+ tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
+ spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+ tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
+ out_alua_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
+ nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
+ spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+ /*
+ * Process ALUA_ACCESS_STATE_ACTIVE_OPTMIZED in a seperate conditional
+ * statement so the complier knows explictly to check this case first.
+ * For the Optimized ALUA access state case, we want to process the
+ * incoming fabric cmd ASAP..
+ */
+ if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTMIZED)
+ return 0;
+
+ switch (out_alua_state) {
+ case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
+ return core_alua_state_nonoptimized(cmd, cdb,
+ nonop_delay_msecs, alua_ascq);
+ case ALUA_ACCESS_STATE_STANDBY:
+ return core_alua_state_standby(cmd, cdb, alua_ascq);
+ case ALUA_ACCESS_STATE_UNAVAILABLE:
+ return core_alua_state_unavailable(cmd, cdb, alua_ascq);
+ case ALUA_ACCESS_STATE_TRANSITION:
+ return core_alua_state_transition(cmd, cdb, alua_ascq);
+ /*
+ * OFFLINE is a secondary ALUA target port group access state, that is
+ * handled above with struct se_port->sep_tg_pt_secondary_offline=1
+ */
+ case ALUA_ACCESS_STATE_OFFLINE:
+ default:
+ printk(KERN_ERR "Unknown ALUA access state: 0x%02x\n",
+ out_alua_state);
+ return -1;
+ }
+
+ return 0;
+}
+
+/*
+ * Check implict and explict ALUA state change request.
+ */
+int core_alua_check_transition(int state, int *primary)
+{
+ switch (state) {
+ case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
+ case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
+ case ALUA_ACCESS_STATE_STANDBY:
+ case ALUA_ACCESS_STATE_UNAVAILABLE:
+ /*
+ * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
+ * defined as primary target port asymmetric access states.
+ */
+ *primary = 1;
+ break;
+ case ALUA_ACCESS_STATE_OFFLINE:
+ /*
+ * OFFLINE state is defined as a secondary target port
+ * asymmetric access state.
+ */
+ *primary = 0;
+ break;
+ default:
+ printk(KERN_ERR "Unknown ALUA access state: 0x%02x\n", state);
+ return -1;
+ }
+
+ return 0;
+}
+
+char *core_alua_dump_state(int state)
+{
+ switch (state) {
+ case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
+ return "Active/Optimized";
+ case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
+ return "Active/NonOptimized";
+ case ALUA_ACCESS_STATE_STANDBY:
+ return "Standby";
+ case ALUA_ACCESS_STATE_UNAVAILABLE:
+ return "Unavailable";
+ case ALUA_ACCESS_STATE_OFFLINE:
+ return "Offline";
+ default:
+ return "Unknown";
+ }
+
+ return NULL;
+}
+
+char *core_alua_dump_status(int status)
+{
+ switch (status) {
+ case ALUA_STATUS_NONE:
+ return "None";
+ case ALUA_STATUS_ALTERED_BY_EXPLICT_STPG:
+ return "Altered by Explict STPG";
+ case ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA:
+ return "Altered by Implict ALUA";
+ default:
+ return "Unknown";
+ }
+
+ return NULL;
+}
+
+/*
+ * Used by fabric modules to determine when we need to delay processing
+ * for the Active/NonOptimized paths..
+ */
+int core_alua_check_nonop_delay(
+ struct se_cmd *cmd)
+{
+ if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
+ return 0;
+ if (in_interrupt())
+ return 0;
+ /*
+ * The ALUA Active/NonOptimized access state delay can be disabled
+ * in via configfs with a value of zero
+ */
+ if (!(cmd->alua_nonop_delay))
+ return 0;
+ /*
+ * struct se_cmd->alua_nonop_delay gets set by a target port group
+ * defined interval in core_alua_state_nonoptimized()
+ */
+ msleep_interruptible(cmd->alua_nonop_delay);
+ return 0;
+}
+EXPORT_SYMBOL(core_alua_check_nonop_delay);
+
+/*
+ * Called with tg_pt_gp->tg_pt_gp_md_mutex or tg_pt_gp_mem->sep_tg_pt_md_mutex
+ *
+ */
+int core_alua_write_tpg_metadata(
+ const char *path,
+ unsigned char *md_buf,
+ u32 md_buf_len)
+{
+ mm_segment_t old_fs;
+ struct file *file;
+ struct iovec iov[1];
+ int flags = O_RDWR | O_CREAT | O_TRUNC, ret;
+
+ memset(iov, 0, sizeof(struct iovec));
+
+ file = filp_open(path, flags, 0600);
+ if (IS_ERR(file) || !file || !file->f_dentry) {
+ printk(KERN_ERR "filp_open(%s) for ALUA metadata failed\n",
+ path);
+ return -ENODEV;
+ }
+
+ iov[0].iov_base = &md_buf[0];
+ iov[0].iov_len = md_buf_len;
+
+ old_fs = get_fs();
+ set_fs(get_ds());
+ ret = vfs_writev(file, &iov[0], 1, &file->f_pos);
+ set_fs(old_fs);
+
+ if (ret < 0) {
+ printk(KERN_ERR "Error writing ALUA metadata file: %s\n", path);
+ filp_close(file, NULL);
+ return -EIO;
+ }
+ filp_close(file, NULL);
+
+ return 0;
+}
+
+/*
+ * Called with tg_pt_gp->tg_pt_gp_md_mutex held
+ */
+int core_alua_update_tpg_primary_metadata(
+ struct t10_alua_tg_pt_gp *tg_pt_gp,
+ int primary_state,
+ unsigned char *md_buf)
+{
+ struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
+ struct t10_wwn *wwn = &su_dev->t10_wwn;
+ char path[ALUA_METADATA_PATH_LEN];
+ int len;
+
+ memset(path, 0, ALUA_METADATA_PATH_LEN);
+
+ len = snprintf(md_buf, tg_pt_gp->tg_pt_gp_md_buf_len,
+ "tg_pt_gp_id=%hu\n"
+ "alua_access_state=0x%02x\n"
+ "alua_access_status=0x%02x\n",
+ tg_pt_gp->tg_pt_gp_id, primary_state,
+ tg_pt_gp->tg_pt_gp_alua_access_status);
+
+ snprintf(path, ALUA_METADATA_PATH_LEN,
+ "/var/target/alua/tpgs_%s/%s", &wwn->unit_serial[0],
+ config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
+
+ return core_alua_write_tpg_metadata(path, md_buf, len);
+}
+
+int core_alua_do_transition_tg_pt(
+ struct t10_alua_tg_pt_gp *tg_pt_gp,
+ struct se_port *l_port,
+ struct se_node_acl *nacl,
+ unsigned char *md_buf,
+ int new_state,
+ int explict)
+{
+ struct se_dev_entry *se_deve;
+ struct se_lun_acl *lacl;
+ struct se_port *port;
+ struct t10_alua_tg_pt_gp_member *mem;
+ int old_state = 0;
+ /*
+ * Save the old primary ALUA access state, and set the current state
+ * to ALUA_ACCESS_STATE_TRANSITION.
+ */
+ old_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
+ atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
+ ALUA_ACCESS_STATE_TRANSITION);
+ tg_pt_gp->tg_pt_gp_alua_access_status = (explict) ?
+ ALUA_STATUS_ALTERED_BY_EXPLICT_STPG :
+ ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA;
+ /*
+ * Check for the optional ALUA primary state transition delay
+ */
+ if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
+ msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
+
+ spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+ list_for_each_entry(mem, &tg_pt_gp->tg_pt_gp_mem_list,
+ tg_pt_gp_mem_list) {
+ port = mem->tg_pt;
+ /*
+ * After an implicit target port asymmetric access state
+ * change, a device server shall establish a unit attention
+ * condition for the initiator port associated with every I_T
+ * nexus with the additional sense code set to ASYMMETRIC
+ * ACCESS STATE CHAGED.
+ *
+ * After an explicit target port asymmetric access state
+ * change, a device server shall establish a unit attention
+ * condition with the additional sense code set to ASYMMETRIC
+ * ACCESS STATE CHANGED for the initiator port associated with
+ * every I_T nexus other than the I_T nexus on which the SET
+ * TARGET PORT GROUPS command
+ */
+ atomic_inc(&mem->tg_pt_gp_mem_ref_cnt);
+ smp_mb__after_atomic_inc();
+ spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+
+ spin_lock_bh(&port->sep_alua_lock);
+ list_for_each_entry(se_deve, &port->sep_alua_list,
+ alua_port_list) {
+ lacl = se_deve->se_lun_acl;
+ /*
+ * se_deve->se_lun_acl pointer may be NULL for a
+ * entry created without explict Node+MappedLUN ACLs
+ */
+ if (!(lacl))
+ continue;
+
+ if (explict &&
+ (nacl != NULL) && (nacl == lacl->se_lun_nacl) &&
+ (l_port != NULL) && (l_port == port))
+ continue;
+
+ core_scsi3_ua_allocate(lacl->se_lun_nacl,
+ se_deve->mapped_lun, 0x2A,
+ ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
+ }
+ spin_unlock_bh(&port->sep_alua_lock);
+
+ spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+ atomic_dec(&mem->tg_pt_gp_mem_ref_cnt);
+ smp_mb__after_atomic_dec();
+ }
+ spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+ /*
+ * Update the ALUA metadata buf that has been allocated in
+ * core_alua_do_port_transition(), this metadata will be written
+ * to struct file.
+ *
+ * Note that there is the case where we do not want to update the
+ * metadata when the saved metadata is being parsed in userspace
+ * when setting the existing port access state and access status.
+ *
+ * Also note that the failure to write out the ALUA metadata to
+ * struct file does NOT affect the actual ALUA transition.
+ */
+ if (tg_pt_gp->tg_pt_gp_write_metadata) {
+ mutex_lock(&tg_pt_gp->tg_pt_gp_md_mutex);
+ core_alua_update_tpg_primary_metadata(tg_pt_gp,
+ new_state, md_buf);
+ mutex_unlock(&tg_pt_gp->tg_pt_gp_md_mutex);
+ }
+ /*
+ * Set the current primary ALUA access state to the requested new state
+ */
+ atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state, new_state);
+
+ printk(KERN_INFO "Successful %s ALUA transition TG PT Group: %s ID: %hu"
+ " from primary access state %s to %s\n", (explict) ? "explict" :
+ "implict", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
+ tg_pt_gp->tg_pt_gp_id, core_alua_dump_state(old_state),
+ core_alua_dump_state(new_state));
+
+ return 0;
+}
+
+int core_alua_do_port_transition(
+ struct t10_alua_tg_pt_gp *l_tg_pt_gp,
+ struct se_device *l_dev,
+ struct se_port *l_port,
+ struct se_node_acl *l_nacl,
+ int new_state,
+ int explict)
+{
+ struct se_device *dev;
+ struct se_port *port;
+ struct se_subsystem_dev *su_dev;
+ struct se_node_acl *nacl;
+ struct t10_alua_lu_gp *lu_gp;
+ struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
+ struct t10_alua_tg_pt_gp *tg_pt_gp;
+ unsigned char *md_buf;
+ int primary;
+
+ if (core_alua_check_transition(new_state, &primary) != 0)
+ return -EINVAL;
+
+ md_buf = kzalloc(l_tg_pt_gp->tg_pt_gp_md_buf_len, GFP_KERNEL);
+ if (!(md_buf)) {
+ printk("Unable to allocate buf for ALUA metadata\n");
+ return -ENOMEM;
+ }
+
+ local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
+ spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
+ lu_gp = local_lu_gp_mem->lu_gp;
+ atomic_inc(&lu_gp->lu_gp_ref_cnt);
+ smp_mb__after_atomic_inc();
+ spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
+ /*
+ * For storage objects that are members of the 'default_lu_gp',
+ * we only do transition on the passed *l_tp_pt_gp, and not
+ * on all of the matching target port groups IDs in default_lu_gp.
+ */
+ if (!(lu_gp->lu_gp_id)) {
+ /*
+ * core_alua_do_transition_tg_pt() will always return
+ * success.
+ */
+ core_alua_do_transition_tg_pt(l_tg_pt_gp, l_port, l_nacl,
+ md_buf, new_state, explict);
+ atomic_dec(&lu_gp->lu_gp_ref_cnt);
+ smp_mb__after_atomic_dec();
+ kfree(md_buf);
+ return 0;
+ }
+ /*
+ * For all other LU groups aside from 'default_lu_gp', walk all of
+ * the associated storage objects looking for a matching target port
+ * group ID from the local target port group.
+ */
+ spin_lock(&lu_gp->lu_gp_lock);
+ list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
+ lu_gp_mem_list) {
+
+ dev = lu_gp_mem->lu_gp_mem_dev;
+ su_dev = dev->se_sub_dev;
+ atomic_inc(&lu_gp_mem->lu_gp_mem_ref_cnt);
+ smp_mb__after_atomic_inc();
+ spin_unlock(&lu_gp->lu_gp_lock);
+
+ spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ list_for_each_entry(tg_pt_gp,
+ &T10_ALUA(su_dev)->tg_pt_gps_list,
+ tg_pt_gp_list) {
+
+ if (!(tg_pt_gp->tg_pt_gp_valid_id))
+ continue;
+ /*
+ * If the target behavior port asymmetric access state
+ * is changed for any target port group accessiable via
+ * a logical unit within a LU group, the target port
+ * behavior group asymmetric access states for the same
+ * target port group accessible via other logical units
+ * in that LU group will also change.
+ */
+ if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
+ continue;
+
+ if (l_tg_pt_gp == tg_pt_gp) {
+ port = l_port;
+ nacl = l_nacl;
+ } else {
+ port = NULL;
+ nacl = NULL;
+ }
+ atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
+ smp_mb__after_atomic_inc();
+ spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ /*
+ * core_alua_do_transition_tg_pt() will always return
+ * success.
+ */
+ core_alua_do_transition_tg_pt(tg_pt_gp, port,
+ nacl, md_buf, new_state, explict);
+
+ spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
+ smp_mb__after_atomic_dec();
+ }
+ spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+
+ spin_lock(&lu_gp->lu_gp_lock);
+ atomic_dec(&lu_gp_mem->lu_gp_mem_ref_cnt);
+ smp_mb__after_atomic_dec();
+ }
+ spin_unlock(&lu_gp->lu_gp_lock);
+
+ printk(KERN_INFO "Successfully processed LU Group: %s all ALUA TG PT"
+ " Group IDs: %hu %s transition to primary state: %s\n",
+ config_item_name(&lu_gp->lu_gp_group.cg_item),
+ l_tg_pt_gp->tg_pt_gp_id, (explict) ? "explict" : "implict",
+ core_alua_dump_state(new_state));
+
+ atomic_dec(&lu_gp->lu_gp_ref_cnt);
+ smp_mb__after_atomic_dec();
+ kfree(md_buf);
+ return 0;
+}
+
+/*
+ * Called with tg_pt_gp_mem->sep_tg_pt_md_mutex held
+ */
+int core_alua_update_tpg_secondary_metadata(
+ struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
+ struct se_port *port,
+ unsigned char *md_buf,
+ u32 md_buf_len)
+{
+ struct se_portal_group *se_tpg = port->sep_tpg;
+ char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
+ int len;
+
+ memset(path, 0, ALUA_METADATA_PATH_LEN);
+ memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
+
+ len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
+ TPG_TFO(se_tpg)->tpg_get_wwn(se_tpg));
+
+ if (TPG_TFO(se_tpg)->tpg_get_tag != NULL)
+ snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
+ TPG_TFO(se_tpg)->tpg_get_tag(se_tpg));
+
+ len = snprintf(md_buf, md_buf_len, "alua_tg_pt_offline=%d\n"
+ "alua_tg_pt_status=0x%02x\n",
+ atomic_read(&port->sep_tg_pt_secondary_offline),
+ port->sep_tg_pt_secondary_stat);
+
+ snprintf(path, ALUA_METADATA_PATH_LEN, "/var/target/alua/%s/%s/lun_%u",
+ TPG_TFO(se_tpg)->get_fabric_name(), wwn,
+ port->sep_lun->unpacked_lun);
+
+ return core_alua_write_tpg_metadata(path, md_buf, len);
+}
+
+int core_alua_set_tg_pt_secondary_state(
+ struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
+ struct se_port *port,
+ int explict,
+ int offline)
+{
+ struct t10_alua_tg_pt_gp *tg_pt_gp;
+ unsigned char *md_buf;
+ u32 md_buf_len;
+ int trans_delay_msecs;
+
+ spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+ tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
+ if (!(tg_pt_gp)) {
+ spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+ printk(KERN_ERR "Unable to complete secondary state"
+ " transition\n");
+ return -1;
+ }
+ trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
+ /*
+ * Set the secondary ALUA target port access state to OFFLINE
+ * or release the previously secondary state for struct se_port
+ */
+ if (offline)
+ atomic_set(&port->sep_tg_pt_secondary_offline, 1);
+ else
+ atomic_set(&port->sep_tg_pt_secondary_offline, 0);
+
+ md_buf_len = tg_pt_gp->tg_pt_gp_md_buf_len;
+ port->sep_tg_pt_secondary_stat = (explict) ?
+ ALUA_STATUS_ALTERED_BY_EXPLICT_STPG :
+ ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA;
+
+ printk(KERN_INFO "Successful %s ALUA transition TG PT Group: %s ID: %hu"
+ " to secondary access state: %s\n", (explict) ? "explict" :
+ "implict", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
+ tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
+
+ spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+ /*
+ * Do the optional transition delay after we set the secondary
+ * ALUA access state.
+ */
+ if (trans_delay_msecs != 0)
+ msleep_interruptible(trans_delay_msecs);
+ /*
+ * See if we need to update the ALUA fabric port metadata for
+ * secondary state and status
+ */
+ if (port->sep_tg_pt_secondary_write_md) {
+ md_buf = kzalloc(md_buf_len, GFP_KERNEL);
+ if (!(md_buf)) {
+ printk(KERN_ERR "Unable to allocate md_buf for"
+ " secondary ALUA access metadata\n");
+ return -1;
+ }
+ mutex_lock(&port->sep_tg_pt_md_mutex);
+ core_alua_update_tpg_secondary_metadata(tg_pt_gp_mem, port,
+ md_buf, md_buf_len);
+ mutex_unlock(&port->sep_tg_pt_md_mutex);
+
+ kfree(md_buf);
+ }
+
+ return 0;
+}
+
+struct t10_alua_lu_gp *core_alua_allocate_lu_gp(const char *name, int def_group)
+{
+ struct t10_alua_lu_gp *lu_gp;
+
+ lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
+ if (!(lu_gp)) {
+ printk(KERN_ERR "Unable to allocate struct t10_alua_lu_gp\n");
+ return ERR_PTR(-ENOMEM);;
+ }
+ INIT_LIST_HEAD(&lu_gp->lu_gp_list);
+ INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
+ spin_lock_init(&lu_gp->lu_gp_lock);
+ atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
+
+ if (def_group) {
+ lu_gp->lu_gp_id = se_global->alua_lu_gps_counter++;;
+ lu_gp->lu_gp_valid_id = 1;
+ se_global->alua_lu_gps_count++;
+ }
+
+ return lu_gp;
+}
+
+int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
+{
+ struct t10_alua_lu_gp *lu_gp_tmp;
+ u16 lu_gp_id_tmp;
+ /*
+ * The lu_gp->lu_gp_id may only be set once..
+ */
+ if (lu_gp->lu_gp_valid_id) {
+ printk(KERN_WARNING "ALUA LU Group already has a valid ID,"
+ " ignoring request\n");
+ return -1;
+ }
+
+ spin_lock(&se_global->lu_gps_lock);
+ if (se_global->alua_lu_gps_count == 0x0000ffff) {
+ printk(KERN_ERR "Maximum ALUA se_global->alua_lu_gps_count:"
+ " 0x0000ffff reached\n");
+ spin_unlock(&se_global->lu_gps_lock);
+ kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
+ return -1;
+ }
+again:
+ lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
+ se_global->alua_lu_gps_counter++;
+
+ list_for_each_entry(lu_gp_tmp, &se_global->g_lu_gps_list, lu_gp_list) {
+ if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
+ if (!(lu_gp_id))
+ goto again;
+
+ printk(KERN_WARNING "ALUA Logical Unit Group ID: %hu"
+ " already exists, ignoring request\n",
+ lu_gp_id);
+ spin_unlock(&se_global->lu_gps_lock);
+ return -1;
+ }
+ }
+
+ lu_gp->lu_gp_id = lu_gp_id_tmp;
+ lu_gp->lu_gp_valid_id = 1;
+ list_add_tail(&lu_gp->lu_gp_list, &se_global->g_lu_gps_list);
+ se_global->alua_lu_gps_count++;
+ spin_unlock(&se_global->lu_gps_lock);
+
+ return 0;
+}
+
+struct t10_alua_lu_gp_member *core_alua_allocate_lu_gp_mem(
+ struct se_device *dev)
+{
+ struct t10_alua_lu_gp_member *lu_gp_mem;
+
+ lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
+ if (!(lu_gp_mem)) {
+ printk(KERN_ERR "Unable to allocate struct t10_alua_lu_gp_member\n");
+ return ERR_PTR(-ENOMEM);
+ }
+ INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
+ spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
+ atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
+
+ lu_gp_mem->lu_gp_mem_dev = dev;
+ dev->dev_alua_lu_gp_mem = lu_gp_mem;
+
+ return lu_gp_mem;
+}
+
+void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
+{
+ struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
+ /*
+ * Once we have reached this point, config_item_put() has
+ * already been called from target_core_alua_drop_lu_gp().
+ *
+ * Here, we remove the *lu_gp from the global list so that
+ * no associations can be made while we are releasing
+ * struct t10_alua_lu_gp.
+ */
+ spin_lock(&se_global->lu_gps_lock);
+ atomic_set(&lu_gp->lu_gp_shutdown, 1);
+ list_del(&lu_gp->lu_gp_list);
+ se_global->alua_lu_gps_count--;
+ spin_unlock(&se_global->lu_gps_lock);
+ /*
+ * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
+ * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
+ * released with core_alua_put_lu_gp_from_name()
+ */
+ while (atomic_read(&lu_gp->lu_gp_ref_cnt))
+ cpu_relax();
+ /*
+ * Release reference to struct t10_alua_lu_gp * from all associated
+ * struct se_device.
+ */
+ spin_lock(&lu_gp->lu_gp_lock);
+ list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
+ &lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
+ if (lu_gp_mem->lu_gp_assoc) {
+ list_del(&lu_gp_mem->lu_gp_mem_list);
+ lu_gp->lu_gp_members--;
+ lu_gp_mem->lu_gp_assoc = 0;
+ }
+ spin_unlock(&lu_gp->lu_gp_lock);
+ /*
+ *
+ * lu_gp_mem is assoicated with a single
+ * struct se_device->dev_alua_lu_gp_mem, and is released when
+ * struct se_device is released via core_alua_free_lu_gp_mem().
+ *
+ * If the passed lu_gp does NOT match the default_lu_gp, assume
+ * we want to re-assocate a given lu_gp_mem with default_lu_gp.
+ */
+ spin_lock(&lu_gp_mem->lu_gp_mem_lock);
+ if (lu_gp != se_global->default_lu_gp)
+ __core_alua_attach_lu_gp_mem(lu_gp_mem,
+ se_global->default_lu_gp);
+ else
+ lu_gp_mem->lu_gp = NULL;
+ spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
+
+ spin_lock(&lu_gp->lu_gp_lock);
+ }
+ spin_unlock(&lu_gp->lu_gp_lock);
+
+ kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
+}
+
+void core_alua_free_lu_gp_mem(struct se_device *dev)
+{
+ struct se_subsystem_dev *su_dev = dev->se_sub_dev;
+ struct t10_alua *alua = T10_ALUA(su_dev);
+ struct t10_alua_lu_gp *lu_gp;
+ struct t10_alua_lu_gp_member *lu_gp_mem;
+
+ if (alua->alua_type != SPC3_ALUA_EMULATED)
+ return;
+
+ lu_gp_mem = dev->dev_alua_lu_gp_mem;
+ if (!(lu_gp_mem))
+ return;
+
+ while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
+ cpu_relax();
+
+ spin_lock(&lu_gp_mem->lu_gp_mem_lock);
+ lu_gp = lu_gp_mem->lu_gp;
+ if ((lu_gp)) {
+ spin_lock(&lu_gp->lu_gp_lock);
+ if (lu_gp_mem->lu_gp_assoc) {
+ list_del(&lu_gp_mem->lu_gp_mem_list);
+ lu_gp->lu_gp_members--;
+ lu_gp_mem->lu_gp_assoc = 0;
+ }
+ spin_unlock(&lu_gp->lu_gp_lock);
+ lu_gp_mem->lu_gp = NULL;
+ }
+ spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
+
+ kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
+}
+
+struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
+{
+ struct t10_alua_lu_gp *lu_gp;
+ struct config_item *ci;
+
+ spin_lock(&se_global->lu_gps_lock);
+ list_for_each_entry(lu_gp, &se_global->g_lu_gps_list, lu_gp_list) {
+ if (!(lu_gp->lu_gp_valid_id))
+ continue;
+ ci = &lu_gp->lu_gp_group.cg_item;
+ if (!(strcmp(config_item_name(ci), name))) {
+ atomic_inc(&lu_gp->lu_gp_ref_cnt);
+ spin_unlock(&se_global->lu_gps_lock);
+ return lu_gp;
+ }
+ }
+ spin_unlock(&se_global->lu_gps_lock);
+
+ return NULL;
+}
+
+void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
+{
+ spin_lock(&se_global->lu_gps_lock);
+ atomic_dec(&lu_gp->lu_gp_ref_cnt);
+ spin_unlock(&se_global->lu_gps_lock);
+}
+
+/*
+ * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
+ */
+void __core_alua_attach_lu_gp_mem(
+ struct t10_alua_lu_gp_member *lu_gp_mem,
+ struct t10_alua_lu_gp *lu_gp)
+{
+ spin_lock(&lu_gp->lu_gp_lock);
+ lu_gp_mem->lu_gp = lu_gp;
+ lu_gp_mem->lu_gp_assoc = 1;
+ list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
+ lu_gp->lu_gp_members++;
+ spin_unlock(&lu_gp->lu_gp_lock);
+}
+
+/*
+ * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
+ */
+void __core_alua_drop_lu_gp_mem(
+ struct t10_alua_lu_gp_member *lu_gp_mem,
+ struct t10_alua_lu_gp *lu_gp)
+{
+ spin_lock(&lu_gp->lu_gp_lock);
+ list_del(&lu_gp_mem->lu_gp_mem_list);
+ lu_gp_mem->lu_gp = NULL;
+ lu_gp_mem->lu_gp_assoc = 0;
+ lu_gp->lu_gp_members--;
+ spin_unlock(&lu_gp->lu_gp_lock);
+}
+
+struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(
+ struct se_subsystem_dev *su_dev,
+ const char *name,
+ int def_group)
+{
+ struct t10_alua_tg_pt_gp *tg_pt_gp;
+
+ tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
+ if (!(tg_pt_gp)) {
+ printk(KERN_ERR "Unable to allocate struct t10_alua_tg_pt_gp\n");
+ return NULL;
+ }
+ INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
+ INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_mem_list);
+ mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
+ spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
+ atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
+ tg_pt_gp->tg_pt_gp_su_dev = su_dev;
+ tg_pt_gp->tg_pt_gp_md_buf_len = ALUA_MD_BUF_LEN;
+ atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
+ ALUA_ACCESS_STATE_ACTIVE_OPTMIZED);
+ /*
+ * Enable both explict and implict ALUA support by default
+ */
+ tg_pt_gp->tg_pt_gp_alua_access_type =
+ TPGS_EXPLICT_ALUA | TPGS_IMPLICT_ALUA;
+ /*
+ * Set the default Active/NonOptimized Delay in milliseconds
+ */
+ tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
+ tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
+
+ if (def_group) {
+ spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ tg_pt_gp->tg_pt_gp_id =
+ T10_ALUA(su_dev)->alua_tg_pt_gps_counter++;
+ tg_pt_gp->tg_pt_gp_valid_id = 1;
+ T10_ALUA(su_dev)->alua_tg_pt_gps_count++;
+ list_add_tail(&tg_pt_gp->tg_pt_gp_list,
+ &T10_ALUA(su_dev)->tg_pt_gps_list);
+ spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ }
+
+ return tg_pt_gp;
+}
+
+int core_alua_set_tg_pt_gp_id(
+ struct t10_alua_tg_pt_gp *tg_pt_gp,
+ u16 tg_pt_gp_id)
+{
+ struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
+ struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
+ u16 tg_pt_gp_id_tmp;
+ /*
+ * The tg_pt_gp->tg_pt_gp_id may only be set once..
+ */
+ if (tg_pt_gp->tg_pt_gp_valid_id) {
+ printk(KERN_WARNING "ALUA TG PT Group already has a valid ID,"
+ " ignoring request\n");
+ return -1;
+ }
+
+ spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ if (T10_ALUA(su_dev)->alua_tg_pt_gps_count == 0x0000ffff) {
+ printk(KERN_ERR "Maximum ALUA alua_tg_pt_gps_count:"
+ " 0x0000ffff reached\n");
+ spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
+ return -1;
+ }
+again:
+ tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
+ T10_ALUA(su_dev)->alua_tg_pt_gps_counter++;
+
+ list_for_each_entry(tg_pt_gp_tmp, &T10_ALUA(su_dev)->tg_pt_gps_list,
+ tg_pt_gp_list) {
+ if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
+ if (!(tg_pt_gp_id))
+ goto again;
+
+ printk(KERN_ERR "ALUA Target Port Group ID: %hu already"
+ " exists, ignoring request\n", tg_pt_gp_id);
+ spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ return -1;
+ }
+ }
+
+ tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
+ tg_pt_gp->tg_pt_gp_valid_id = 1;
+ list_add_tail(&tg_pt_gp->tg_pt_gp_list,
+ &T10_ALUA(su_dev)->tg_pt_gps_list);
+ T10_ALUA(su_dev)->alua_tg_pt_gps_count++;
+ spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+
+ return 0;
+}
+
+struct t10_alua_tg_pt_gp_member *core_alua_allocate_tg_pt_gp_mem(
+ struct se_port *port)
+{
+ struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
+
+ tg_pt_gp_mem = kmem_cache_zalloc(t10_alua_tg_pt_gp_mem_cache,
+ GFP_KERNEL);
+ if (!(tg_pt_gp_mem)) {
+ printk(KERN_ERR "Unable to allocate struct t10_alua_tg_pt_gp_member\n");
+ return ERR_PTR(-ENOMEM);
+ }
+ INIT_LIST_HEAD(&tg_pt_gp_mem->tg_pt_gp_mem_list);
+ spin_lock_init(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+ atomic_set(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt, 0);
+
+ tg_pt_gp_mem->tg_pt = port;
+ port->sep_alua_tg_pt_gp_mem = tg_pt_gp_mem;
+ atomic_set(&port->sep_tg_pt_gp_active, 1);
+
+ return tg_pt_gp_mem;
+}
+
+void core_alua_free_tg_pt_gp(
+ struct t10_alua_tg_pt_gp *tg_pt_gp)
+{
+ struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
+ struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *tg_pt_gp_mem_tmp;
+ /*
+ * Once we have reached this point, config_item_put() has already
+ * been called from target_core_alua_drop_tg_pt_gp().
+ *
+ * Here we remove *tg_pt_gp from the global list so that
+ * no assications *OR* explict ALUA via SET_TARGET_PORT_GROUPS
+ * can be made while we are releasing struct t10_alua_tg_pt_gp.
+ */
+ spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ list_del(&tg_pt_gp->tg_pt_gp_list);
+ T10_ALUA(su_dev)->alua_tg_pt_gps_counter--;
+ spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ /*
+ * Allow a struct t10_alua_tg_pt_gp_member * referenced by
+ * core_alua_get_tg_pt_gp_by_name() in
+ * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
+ * to be released with core_alua_put_tg_pt_gp_from_name().
+ */
+ while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
+ cpu_relax();
+ /*
+ * Release reference to struct t10_alua_tg_pt_gp from all associated
+ * struct se_port.
+ */
+ spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+ list_for_each_entry_safe(tg_pt_gp_mem, tg_pt_gp_mem_tmp,
+ &tg_pt_gp->tg_pt_gp_mem_list, tg_pt_gp_mem_list) {
+ if (tg_pt_gp_mem->tg_pt_gp_assoc) {
+ list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
+ tg_pt_gp->tg_pt_gp_members--;
+ tg_pt_gp_mem->tg_pt_gp_assoc = 0;
+ }
+ spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+ /*
+ * tg_pt_gp_mem is assoicated with a single
+ * se_port->sep_alua_tg_pt_gp_mem, and is released via
+ * core_alua_free_tg_pt_gp_mem().
+ *
+ * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
+ * assume we want to re-assocate a given tg_pt_gp_mem with
+ * default_tg_pt_gp.
+ */
+ spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+ if (tg_pt_gp != T10_ALUA(su_dev)->default_tg_pt_gp) {
+ __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
+ T10_ALUA(su_dev)->default_tg_pt_gp);
+ } else
+ tg_pt_gp_mem->tg_pt_gp = NULL;
+ spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+
+ spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+ }
+ spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+
+ kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
+}
+
+void core_alua_free_tg_pt_gp_mem(struct se_port *port)
+{
+ struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
+ struct t10_alua *alua = T10_ALUA(su_dev);
+ struct t10_alua_tg_pt_gp *tg_pt_gp;
+ struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
+
+ if (alua->alua_type != SPC3_ALUA_EMULATED)
+ return;
+
+ tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
+ if (!(tg_pt_gp_mem))
+ return;
+
+ while (atomic_read(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt))
+ cpu_relax();
+
+ spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+ tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
+ if ((tg_pt_gp)) {
+ spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+ if (tg_pt_gp_mem->tg_pt_gp_assoc) {
+ list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
+ tg_pt_gp->tg_pt_gp_members--;
+ tg_pt_gp_mem->tg_pt_gp_assoc = 0;
+ }
+ spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+ tg_pt_gp_mem->tg_pt_gp = NULL;
+ }
+ spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+
+ kmem_cache_free(t10_alua_tg_pt_gp_mem_cache, tg_pt_gp_mem);
+}
+
+struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
+ struct se_subsystem_dev *su_dev,
+ const char *name)
+{
+ struct t10_alua_tg_pt_gp *tg_pt_gp;
+ struct config_item *ci;
+
+ spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ list_for_each_entry(tg_pt_gp, &T10_ALUA(su_dev)->tg_pt_gps_list,
+ tg_pt_gp_list) {
+ if (!(tg_pt_gp->tg_pt_gp_valid_id))
+ continue;
+ ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
+ if (!(strcmp(config_item_name(ci), name))) {
+ atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
+ spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ return tg_pt_gp;
+ }
+ }
+ spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+
+ return NULL;
+}
+
+void core_alua_put_tg_pt_gp_from_name(
+ struct t10_alua_tg_pt_gp *tg_pt_gp)
+{
+ struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
+
+ spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+ atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
+ spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+}
+
+/*
+ * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
+ */
+void __core_alua_attach_tg_pt_gp_mem(
+ struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
+ struct t10_alua_tg_pt_gp *tg_pt_gp)
+{
+ spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+ tg_pt_gp_mem->tg_pt_gp = tg_pt_gp;
+ tg_pt_gp_mem->tg_pt_gp_assoc = 1;
+ list_add_tail(&tg_pt_gp_mem->tg_pt_gp_mem_list,
+ &tg_pt_gp->tg_pt_gp_mem_list);
+ tg_pt_gp->tg_pt_gp_members++;
+ spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+}
+
+/*
+ * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
+ */
+void __core_alua_drop_tg_pt_gp_mem(
+ struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
+ struct t10_alua_tg_pt_gp *tg_pt_gp)
+{
+ spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+ list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
+ tg_pt_gp_mem->tg_pt_gp = NULL;
+ tg_pt_gp_mem->tg_pt_gp_assoc = 0;
+ tg_pt_gp->tg_pt_gp_members--;
+ spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+}
+
+ssize_t core_alua_show_tg_pt_gp_info(struct se_port *port, char *page)
+{
+ struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
+ struct config_item *tg_pt_ci;
+ struct t10_alua *alua = T10_ALUA(su_dev);
+ struct t10_alua_tg_pt_gp *tg_pt_gp;
+ struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
+ ssize_t len = 0;
+
+ if (alua->alua_type != SPC3_ALUA_EMULATED)
+ return len;
+
+ tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
+ if (!(tg_pt_gp_mem))
+ return len;
+
+ spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+ tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
+ if ((tg_pt_gp)) {
+ tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
+ len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
+ " %hu\nTG Port Primary Access State: %s\nTG Port "
+ "Primary Access Status: %s\nTG Port Secondary Access"
+ " State: %s\nTG Port Secondary Access Status: %s\n",
+ config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
+ core_alua_dump_state(atomic_read(
+ &tg_pt_gp->tg_pt_gp_alua_access_state)),
+ core_alua_dump_status(
+ tg_pt_gp->tg_pt_gp_alua_access_status),
+ (atomic_read(&port->sep_tg_pt_secondary_offline)) ?
+ "Offline" : "None",
+ core_alua_dump_status(port->sep_tg_pt_secondary_stat));
+ }
+ spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+
+ return len;
+}
+EXPORT_SYMBOL(core_alua_show_tg_pt_gp_info);
+
+ssize_t core_alua_store_tg_pt_gp_info(
+ struct se_port *port,
+ const char *page,
+ size_t count)
+{
+ struct se_portal_group *tpg;
+ struct se_lun *lun;
+ struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
+ struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
+ struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
+ unsigned char buf[TG_PT_GROUP_NAME_BUF];
+ int move = 0;
+
+ tpg = port->sep_tpg;
+ lun = port->sep_lun;
+
+ if (T10_ALUA(su_dev)->alua_type != SPC3_ALUA_EMULATED) {
+ printk(KERN_WARNING "SPC3_ALUA_EMULATED not enabled for"
+ " %s/tpgt_%hu/%s\n", TPG_TFO(tpg)->tpg_get_wwn(tpg),
+ TPG_TFO(tpg)->tpg_get_tag(tpg),
+ config_item_name(&lun->lun_group.cg_item));
+ return -EINVAL;
+ }
+
+ if (count > TG_PT_GROUP_NAME_BUF) {
+ printk(KERN_ERR "ALUA Target Port Group alias too large!\n");
+ return -EINVAL;
+ }
+ memset(buf, 0, TG_PT_GROUP_NAME_BUF);
+ memcpy(buf, page, count);
+ /*
+ * Any ALUA target port group alias besides "NULL" means we will be
+ * making a new group association.
+ */
+ if (strcmp(strstrip(buf), "NULL")) {
+ /*
+ * core_alua_get_tg_pt_gp_by_name() will increment reference to
+ * struct t10_alua_tg_pt_gp. This reference is released with
+ * core_alua_put_tg_pt_gp_from_name() below.
+ */
+ tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(su_dev,
+ strstrip(buf));
+ if (!(tg_pt_gp_new))
+ return -ENODEV;
+ }
+ tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
+ if (!(tg_pt_gp_mem)) {
+ if (tg_pt_gp_new)
+ core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
+ printk(KERN_ERR "NULL struct se_port->sep_alua_tg_pt_gp_mem pointer\n");
+ return -EINVAL;
+ }
+
+ spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+ tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
+ if ((tg_pt_gp)) {
+ /*
+ * Clearing an existing tg_pt_gp association, and replacing
+ * with the default_tg_pt_gp.
+ */
+ if (!(tg_pt_gp_new)) {
+ printk(KERN_INFO "Target_Core_ConfigFS: Moving"
+ " %s/tpgt_%hu/%s from ALUA Target Port Group:"
+ " alua/%s, ID: %hu back to"
+ " default_tg_pt_gp\n",
+ TPG_TFO(tpg)->tpg_get_wwn(tpg),
+ TPG_TFO(tpg)->tpg_get_tag(tpg),
+ config_item_name(&lun->lun_group.cg_item),
+ config_item_name(
+ &tg_pt_gp->tg_pt_gp_group.cg_item),
+ tg_pt_gp->tg_pt_gp_id);
+
+ __core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
+ __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
+ T10_ALUA(su_dev)->default_tg_pt_gp);
+ spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+
+ return count;
+ }
+ /*
+ * Removing existing association of tg_pt_gp_mem with tg_pt_gp
+ */
+ __core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
+ move = 1;
+ }
+ /*
+ * Associate tg_pt_gp_mem with tg_pt_gp_new.
+ */
+ __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp_new);
+ spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+ printk(KERN_INFO "Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
+ " Target Port Group: alua/%s, ID: %hu\n", (move) ?
+ "Moving" : "Adding", TPG_TFO(tpg)->tpg_get_wwn(tpg),
+ TPG_TFO(tpg)->tpg_get_tag(tpg),
+ config_item_name(&lun->lun_group.cg_item),
+ config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
+ tg_pt_gp_new->tg_pt_gp_id);
+
+ core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
+ return count;
+}
+EXPORT_SYMBOL(core_alua_store_tg_pt_gp_info);
+
+ssize_t core_alua_show_access_type(
+ struct t10_alua_tg_pt_gp *tg_pt_gp,
+ char *page)
+{
+ if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA) &&
+ (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICT_ALUA))
+ return sprintf(page, "Implict and Explict\n");
+ else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICT_ALUA)
+ return sprintf(page, "Implict\n");
+ else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA)
+ return sprintf(page, "Explict\n");
+ else
+ return sprintf(page, "None\n");
+}
+
+ssize_t core_alua_store_access_type(
+ struct t10_alua_tg_pt_gp *tg_pt_gp,
+ const char *page,
+ size_t count)
+{
+ unsigned long tmp;
+ int ret;
+
+ ret = strict_strtoul(page, 0, &tmp);
+ if (ret < 0) {
+ printk(KERN_ERR "Unable to extract alua_access_type\n");
+ return -EINVAL;
+ }
+ if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
+ printk(KERN_ERR "Illegal value for alua_access_type:"
+ " %lu\n", tmp);
+ return -EINVAL;
+ }
+ if (tmp == 3)
+ tg_pt_gp->tg_pt_gp_alua_access_type =
+ TPGS_IMPLICT_ALUA | TPGS_EXPLICT_ALUA;
+ else if (tmp == 2)
+ tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICT_ALUA;
+ else if (tmp == 1)
+ tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICT_ALUA;
+ else
+ tg_pt_gp->tg_pt_gp_alua_access_type = 0;
+
+ return count;
+}
+
+ssize_t core_alua_show_nonop_delay_msecs(
+ struct t10_alua_tg_pt_gp *tg_pt_gp,
+ char *page)
+{
+ return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
+}
+
+ssize_t core_alua_store_nonop_delay_msecs(
+ struct t10_alua_tg_pt_gp *tg_pt_gp,
+ const char *page,
+ size_t count)
+{
+ unsigned long tmp;
+ int ret;
+
+ ret = strict_strtoul(page, 0, &tmp);
+ if (ret < 0) {
+ printk(KERN_ERR "Unable to extract nonop_delay_msecs\n");
+ return -EINVAL;
+ }
+ if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
+ printk(KERN_ERR "Passed nonop_delay_msecs: %lu, exceeds"
+ " ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
+ ALUA_MAX_NONOP_DELAY_MSECS);
+ return -EINVAL;
+ }
+ tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
+
+ return count;
+}
+
+ssize_t core_alua_show_trans_delay_msecs(
+ struct t10_alua_tg_pt_gp *tg_pt_gp,
+ char *page)
+{
+ return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
+}
+
+ssize_t core_alua_store_trans_delay_msecs(
+ struct t10_alua_tg_pt_gp *tg_pt_gp,
+ const char *page,
+ size_t count)
+{
+ unsigned long tmp;
+ int ret;
+
+ ret = strict_strtoul(page, 0, &tmp);
+ if (ret < 0) {
+ printk(KERN_ERR "Unable to extract trans_delay_msecs\n");
+ return -EINVAL;
+ }
+ if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
+ printk(KERN_ERR "Passed trans_delay_msecs: %lu, exceeds"
+ " ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
+ ALUA_MAX_TRANS_DELAY_MSECS);
+ return -EINVAL;
+ }
+ tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
+
+ return count;
+}
+
+ssize_t core_alua_show_preferred_bit(
+ struct t10_alua_tg_pt_gp *tg_pt_gp,
+ char *page)
+{
+ return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
+}
+
+ssize_t core_alua_store_preferred_bit(
+ struct t10_alua_tg_pt_gp *tg_pt_gp,
+ const char *page,
+ size_t count)
+{
+ unsigned long tmp;
+ int ret;
+
+ ret = strict_strtoul(page, 0, &tmp);
+ if (ret < 0) {
+ printk(KERN_ERR "Unable to extract preferred ALUA value\n");
+ return -EINVAL;
+ }
+ if ((tmp != 0) && (tmp != 1)) {
+ printk(KERN_ERR "Illegal value for preferred ALUA: %lu\n", tmp);
+ return -EINVAL;
+ }
+ tg_pt_gp->tg_pt_gp_pref = (int)tmp;
+
+ return count;
+}
+
+ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
+{
+ if (!(lun->lun_sep))
+ return -ENODEV;
+
+ return sprintf(page, "%d\n",
+ atomic_read(&lun->lun_sep->sep_tg_pt_secondary_offline));
+}
+EXPORT_SYMBOL(core_alua_show_offline_bit);
+
+ssize_t core_alua_store_offline_bit(
+ struct se_lun *lun,
+ const char *page,
+ size_t count)
+{
+ struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
+ unsigned long tmp;
+ int ret;
+
+ if (!(lun->lun_sep))
+ return -ENODEV;
+
+ ret = strict_strtoul(page, 0, &tmp);
+ if (ret < 0) {
+ printk(KERN_ERR "Unable to extract alua_tg_pt_offline value\n");
+ return -EINVAL;
+ }
+ if ((tmp != 0) && (tmp != 1)) {
+ printk(KERN_ERR "Illegal value for alua_tg_pt_offline: %lu\n",
+ tmp);
+ return -EINVAL;
+ }
+ tg_pt_gp_mem = lun->lun_sep->sep_alua_tg_pt_gp_mem;
+ if (!(tg_pt_gp_mem)) {
+ printk(KERN_ERR "Unable to locate *tg_pt_gp_mem\n");
+ return -EINVAL;
+ }
+
+ ret = core_alua_set_tg_pt_secondary_state(tg_pt_gp_mem,
+ lun->lun_sep, 0, (int)tmp);
+ if (ret < 0)
+ return -EINVAL;
+
+ return count;
+}
+EXPORT_SYMBOL(core_alua_store_offline_bit);
+
+ssize_t core_alua_show_secondary_status(
+ struct se_lun *lun,
+ char *page)
+{
+ return sprintf(page, "%d\n", lun->lun_sep->sep_tg_pt_secondary_stat);
+}
+EXPORT_SYMBOL(core_alua_show_secondary_status);
+
+ssize_t core_alua_store_secondary_status(
+ struct se_lun *lun,
+ const char *page,
+ size_t count)
+{
+ unsigned long tmp;
+ int ret;
+
+ ret = strict_strtoul(page, 0, &tmp);
+ if (ret < 0) {
+ printk(KERN_ERR "Unable to extract alua_tg_pt_status\n");
+ return -EINVAL;
+ }
+ if ((tmp != ALUA_STATUS_NONE) &&
+ (tmp != ALUA_STATUS_ALTERED_BY_EXPLICT_STPG) &&
+ (tmp != ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA)) {
+ printk(KERN_ERR "Illegal value for alua_tg_pt_status: %lu\n",
+ tmp);
+ return -EINVAL;
+ }
+ lun->lun_sep->sep_tg_pt_secondary_stat = (int)tmp;
+
+ return count;
+}
+EXPORT_SYMBOL(core_alua_store_secondary_status);
+
+ssize_t core_alua_show_secondary_write_metadata(
+ struct se_lun *lun,
+ char *page)
+{
+ return sprintf(page, "%d\n",
+ lun->lun_sep->sep_tg_pt_secondary_write_md);
+}
+EXPORT_SYMBOL(core_alua_show_secondary_write_metadata);
+
+ssize_t core_alua_store_secondary_write_metadata(
+ struct se_lun *lun,
+ const char *page,
+ size_t count)
+{
+ unsigned long tmp;
+ int ret;
+
+ ret = strict_strtoul(page, 0, &tmp);
+ if (ret < 0) {
+ printk(KERN_ERR "Unable to extract alua_tg_pt_write_md\n");
+ return -EINVAL;
+ }
+ if ((tmp != 0) && (tmp != 1)) {
+ printk(KERN_ERR "Illegal value for alua_tg_pt_write_md:"
+ " %lu\n", tmp);
+ return -EINVAL;
+ }
+ lun->lun_sep->sep_tg_pt_secondary_write_md = (int)tmp;
+
+ return count;
+}
+EXPORT_SYMBOL(core_alua_store_secondary_write_metadata);
+
+int core_setup_alua(struct se_device *dev, int force_pt)
+{
+ struct se_subsystem_dev *su_dev = dev->se_sub_dev;
+ struct t10_alua *alua = T10_ALUA(su_dev);
+ struct t10_alua_lu_gp_member *lu_gp_mem;
+ /*
+ * If this device is from Target_Core_Mod/pSCSI, use the ALUA logic
+ * of the Underlying SCSI hardware. In Linux/SCSI terms, this can
+ * cause a problem because libata and some SATA RAID HBAs appear
+ * under Linux/SCSI, but emulate SCSI logic themselves.
+ */
+ if (((TRANSPORT(dev)->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) &&
+ !(DEV_ATTRIB(dev)->emulate_alua)) || force_pt) {
+ alua->alua_type = SPC_ALUA_PASSTHROUGH;
+ alua->alua_state_check = &core_alua_state_check_nop;
+ printk(KERN_INFO "%s: Using SPC_ALUA_PASSTHROUGH, no ALUA"
+ " emulation\n", TRANSPORT(dev)->name);
+ return 0;
+ }
+ /*
+ * If SPC-3 or above is reported by real or emulated struct se_device,
+ * use emulated ALUA.
+ */
+ if (TRANSPORT(dev)->get_device_rev(dev) >= SCSI_3) {
+ printk(KERN_INFO "%s: Enabling ALUA Emulation for SPC-3"
+ " device\n", TRANSPORT(dev)->name);
+ /*
+ * Assoicate this struct se_device with the default ALUA
+ * LUN Group.
+ */
+ lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
+ if (IS_ERR(lu_gp_mem) || !lu_gp_mem)
+ return -1;
+
+ alua->alua_type = SPC3_ALUA_EMULATED;
+ alua->alua_state_check = &core_alua_state_check;
+ spin_lock(&lu_gp_mem->lu_gp_mem_lock);
+ __core_alua_attach_lu_gp_mem(lu_gp_mem,
+ se_global->default_lu_gp);
+ spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
+
+ printk(KERN_INFO "%s: Adding to default ALUA LU Group:"
+ " core/alua/lu_gps/default_lu_gp\n",
+ TRANSPORT(dev)->name);
+ } else {
+ alua->alua_type = SPC2_ALUA_DISABLED;
+ alua->alua_state_check = &core_alua_state_check_nop;
+ printk(KERN_INFO "%s: Disabling ALUA Emulation for SPC-2"
+ " device\n", TRANSPORT(dev)->name);
+ }
+
+ return 0;
+}
diff --git a/drivers/target/target_core_alua.h b/drivers/target/target_core_alua.h
new file mode 100644
index 0000000..827f425
--- /dev/null
+++ b/drivers/target/target_core_alua.h
@@ -0,0 +1,142 @@
+#ifndef TARGET_CORE_ALUA_H
+#define TARGET_CORE_ALUA_H
+
+/*
+ * INQUIRY response data, TPGS Field
+ *
+ * from spc4r17 section 6.4.2 Table 135
+ */
+#define TPGS_NO_ALUA 0x00
+#define TPGS_IMPLICT_ALUA 0x10
+#define TPGS_EXPLICT_ALUA 0x20
+
+/*
+ * ASYMMETRIC ACCESS STATE field
+ *
+ * from spc4r17 section 6.27 Table 245
+ */
+#define ALUA_ACCESS_STATE_ACTIVE_OPTMIZED 0x0
+#define ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED 0x1
+#define ALUA_ACCESS_STATE_STANDBY 0x2
+#define ALUA_ACCESS_STATE_UNAVAILABLE 0x3
+#define ALUA_ACCESS_STATE_OFFLINE 0xe
+#define ALUA_ACCESS_STATE_TRANSITION 0xf
+
+/*
+ * REPORT_TARGET_PORT_GROUP STATUS CODE
+ *
+ * from spc4r17 section 6.27 Table 246
+ */
+#define ALUA_STATUS_NONE 0x00
+#define ALUA_STATUS_ALTERED_BY_EXPLICT_STPG 0x01
+#define ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA 0x02
+
+/*
+ * From spc4r17, Table D.1: ASC and ASCQ Assignement
+ */
+#define ASCQ_04H_ALUA_STATE_TRANSITION 0x0a
+#define ASCQ_04H_ALUA_TG_PT_STANDBY 0x0b
+#define ASCQ_04H_ALUA_TG_PT_UNAVAILABLE 0x0c
+#define ASCQ_04H_ALUA_OFFLINE 0x12
+
+/*
+ * Used as the default for Active/NonOptimized delay (in milliseconds)
+ * This can also be changed via configfs on a per target port group basis..
+ */
+#define ALUA_DEFAULT_NONOP_DELAY_MSECS 100
+#define ALUA_MAX_NONOP_DELAY_MSECS 10000 /* 10 seconds */
+/*
+ * Used for implict and explict ALUA transitional delay, that is disabled
+ * by default, and is intended to be used for debugging client side ALUA code.
+ */
+#define ALUA_DEFAULT_TRANS_DELAY_MSECS 0
+#define ALUA_MAX_TRANS_DELAY_MSECS 30000 /* 30 seconds */
+/*
+ * Used by core_alua_update_tpg_primary_metadata() and
+ * core_alua_update_tpg_secondary_metadata()
+ */
+#define ALUA_METADATA_PATH_LEN 512
+/*
+ * Used by core_alua_update_tpg_secondary_metadata()
+ */
+#define ALUA_SECONDARY_METADATA_WWN_LEN 256
+
+extern struct se_global *se_global;
+
+extern struct kmem_cache *t10_alua_lu_gp_cache;
+extern struct kmem_cache *t10_alua_lu_gp_mem_cache;
+extern struct kmem_cache *t10_alua_tg_pt_gp_cache;
+extern struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
+
+extern int core_emulate_report_target_port_groups(struct se_cmd *);
+extern int core_emulate_set_target_port_groups(struct se_cmd *);
+extern int core_alua_check_transition(int, int *);
+extern int core_alua_check_nonop_delay(struct se_cmd *);
+extern int core_alua_do_transition_tg_pt(struct t10_alua_tg_pt_gp *,
+ struct se_port *, struct se_node_acl *,
+ unsigned char *, int, int);
+extern int core_alua_do_port_transition(struct t10_alua_tg_pt_gp *,
+ struct se_device *, struct se_port *,
+ struct se_node_acl *, int, int);
+extern int core_alua_set_tg_pt_secondary_state(
+ struct t10_alua_tg_pt_gp_member *, struct se_port *, int, int);
+extern char *core_alua_dump_state(int);
+extern char *core_alua_dump_status(int);
+extern struct t10_alua_lu_gp *core_alua_allocate_lu_gp(const char *, int);
+extern int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *, u16);
+extern struct t10_alua_lu_gp_member *core_alua_allocate_lu_gp_mem(
+ struct se_device *);
+extern void core_alua_free_lu_gp(struct t10_alua_lu_gp *);
+extern void core_alua_free_lu_gp_mem(struct se_device *);
+extern struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *);
+extern void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *);
+extern void __core_alua_attach_lu_gp_mem(struct t10_alua_lu_gp_member *,
+ struct t10_alua_lu_gp *);
+extern void __core_alua_drop_lu_gp_mem(struct t10_alua_lu_gp_member *,
+ struct t10_alua_lu_gp *);
+extern void core_alua_drop_lu_gp_dev(struct se_device *);
+extern struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(
+ struct se_subsystem_dev *, const char *, int);
+extern int core_alua_set_tg_pt_gp_id(struct t10_alua_tg_pt_gp *, u16);
+extern struct t10_alua_tg_pt_gp_member *core_alua_allocate_tg_pt_gp_mem(
+ struct se_port *);
+extern void core_alua_free_tg_pt_gp(struct t10_alua_tg_pt_gp *);
+extern void core_alua_free_tg_pt_gp_mem(struct se_port *);
+extern struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
+ struct se_subsystem_dev *, const char *);
+extern void core_alua_put_tg_pt_gp_from_name(struct t10_alua_tg_pt_gp *);
+extern void __core_alua_attach_tg_pt_gp_mem(struct t10_alua_tg_pt_gp_member *,
+ struct t10_alua_tg_pt_gp *);
+extern void __core_alua_drop_tg_pt_gp_mem(struct t10_alua_tg_pt_gp_member *,
+ struct t10_alua_tg_pt_gp *);
+extern ssize_t core_alua_show_tg_pt_gp_info(struct se_port *, char *);
+extern ssize_t core_alua_store_tg_pt_gp_info(struct se_port *, const char *,
+ size_t);
+extern ssize_t core_alua_show_access_type(struct t10_alua_tg_pt_gp *, char *);
+extern ssize_t core_alua_store_access_type(struct t10_alua_tg_pt_gp *,
+ const char *, size_t);
+extern ssize_t core_alua_show_nonop_delay_msecs(struct t10_alua_tg_pt_gp *,
+ char *);
+extern ssize_t core_alua_store_nonop_delay_msecs(struct t10_alua_tg_pt_gp *,
+ const char *, size_t);
+extern ssize_t core_alua_show_trans_delay_msecs(struct t10_alua_tg_pt_gp *,
+ char *);
+extern ssize_t core_alua_store_trans_delay_msecs(struct t10_alua_tg_pt_gp *,
+ const char *, size_t);
+extern ssize_t core_alua_show_preferred_bit(struct t10_alua_tg_pt_gp *,
+ char *);
+extern ssize_t core_alua_store_preferred_bit(struct t10_alua_tg_pt_gp *,
+ const char *, size_t);
+extern ssize_t core_alua_show_offline_bit(struct se_lun *, char *);
+extern ssize_t core_alua_store_offline_bit(struct se_lun *, const char *,
+ size_t);
+extern ssize_t core_alua_show_secondary_status(struct se_lun *, char *);
+extern ssize_t core_alua_store_secondary_status(struct se_lun *,
+ const char *, size_t);
+extern ssize_t core_alua_show_secondary_write_metadata(struct se_lun *,
+ char *);
+extern ssize_t core_alua_store_secondary_write_metadata(struct se_lun *,
+ const char *, size_t);
+extern int core_setup_alua(struct se_device *, int);
+
+#endif /* TARGET_CORE_ALUA_H */
--
1.7.3.1

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