/*******************************************************************************
* Filename: target_core_transport.c
*
* This file contains the Generic Target Engine Core.
*
* Copyright (c) 2002, 2003, 2004, 2005 PyX Technologies, Inc.
* Copyright (c) 2005, 2006, 2007 SBE, Inc.
* Copyright (c) 2007-2010 Rising Tide Systems
* Copyright (c) 2008-2010 Linux-iSCSI.org
*
* 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/delay.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/slab.h>
#include <linux/blkdev.h>
#include <linux/spinlock.h>
#include <linux/kthread.h>
#include <linux/in.h>
#include <linux/cdrom.h>
#include <linux/module.h>
#include <asm/unaligned.h>
#include <net/sock.h>
#include <net/tcp.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_tcq.h>
#include <target/target_core_base.h>
#include <target/target_core_backend.h>
#include <target/target_core_fabric.h>
#include <target/target_core_configfs.h>
#include "target_core_internal.h"
#include "target_core_alua.h"
#include "target_core_pr.h"
#include "target_core_ua.h"
static int sub_api_initialized;
static struct workqueue_struct *target_completion_wq;
static struct kmem_cache *se_sess_cache;
struct kmem_cache *se_tmr_req_cache;
struct kmem_cache *se_ua_cache;
struct kmem_cache *t10_pr_reg_cache;
struct kmem_cache *t10_alua_lu_gp_cache;
struct kmem_cache *t10_alua_lu_gp_mem_cache;
struct kmem_cache *t10_alua_tg_pt_gp_cache;
struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
static int transport_generic_write_pending(struct se_cmd *);
static int transport_processing_thread(void *param);
static int __transport_execute_tasks(struct se_device *dev, struct se_cmd *);
static void transport_complete_task_attr(struct se_cmd *cmd);
static void transport_handle_queue_full(struct se_cmd *cmd,
struct se_device *dev);
static void transport_free_dev_tasks(struct se_cmd *cmd);
static int transport_generic_get_mem(struct se_cmd *cmd);
static void transport_put_cmd(struct se_cmd *cmd);
static void transport_remove_cmd_from_queue(struct se_cmd *cmd);
static int transport_set_sense_codes(struct se_cmd *cmd, u8 asc, u8 ascq);
static void transport_generic_request_failure(struct se_cmd *);
static void target_complete_ok_work(struct work_struct *work);
int init_se_kmem_caches(void)
{
se_tmr_req_cache = kmem_cache_create("se_tmr_cache",
sizeof(struct se_tmr_req), __alignof__(struct se_tmr_req),
0, NULL);
if (!se_tmr_req_cache) {
pr_err("kmem_cache_create() for struct se_tmr_req"
" failed\n");
goto out;
}
se_sess_cache = kmem_cache_create("se_sess_cache",
sizeof(struct se_session), __alignof__(struct se_session),
0, NULL);
if (!se_sess_cache) {
pr_err("kmem_cache_create() for struct se_session"
" failed\n");
goto out_free_tmr_req_cache;
}
se_ua_cache = kmem_cache_create("se_ua_cache",
sizeof(struct se_ua), __alignof__(struct se_ua),
0, NULL);
if (!se_ua_cache) {
pr_err("kmem_cache_create() for struct se_ua failed\n");
goto out_free_sess_cache;
}
t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
sizeof(struct t10_pr_registration),
__alignof__(struct t10_pr_registration), 0, NULL);
if (!t10_pr_reg_cache) {
pr_err("kmem_cache_create() for struct t10_pr_registration"
" failed\n");
goto out_free_ua_cache;
}
t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
0, NULL);
if (!t10_alua_lu_gp_cache) {
pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
" failed\n");
goto out_free_pr_reg_cache;
}
t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
sizeof(struct t10_alua_lu_gp_member),
__alignof__(struct t10_alua_lu_gp_member), 0, NULL);
if (!t10_alua_lu_gp_mem_cache) {
pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
"cache failed\n");
goto out_free_lu_gp_cache;
}
t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
sizeof(struct t10_alua_tg_pt_gp),
__alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
if (!t10_alua_tg_pt_gp_cache) {
pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
"cache failed\n");
goto out_free_lu_gp_mem_cache;
}
t10_alua_tg_pt_gp_mem_cache = kmem_cache_create(
"t10_alua_tg_pt_gp_mem_cache",
sizeof(struct t10_alua_tg_pt_gp_member),
__alignof__(struct t10_alua_tg_pt_gp_member),
0, NULL);
if (!t10_alua_tg_pt_gp_mem_cache) {
pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
"mem_t failed\n");
goto out_free_tg_pt_gp_cache;
}
target_completion_wq = alloc_workqueue("target_completion",
WQ_MEM_RECLAIM, 0);
if (!target_completion_wq)
goto out_free_tg_pt_gp_mem_cache;
return 0;
out_free_tg_pt_gp_mem_cache:
kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
out_free_tg_pt_gp_cache:
kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
out_free_lu_gp_mem_cache:
kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
out_free_lu_gp_cache:
kmem_cache_destroy(t10_alua_lu_gp_cache);
out_free_pr_reg_cache:
kmem_cache_destroy(t10_pr_reg_cache);
out_free_ua_cache:
kmem_cache_destroy(se_ua_cache);
out_free_sess_cache:
kmem_cache_destroy(se_sess_cache);
out_free_tmr_req_cache:
kmem_cache_destroy(se_tmr_req_cache);
out:
return -ENOMEM;
}
void release_se_kmem_caches(void)
{
destroy_workqueue(target_completion_wq);
kmem_cache_destroy(se_tmr_req_cache);
kmem_cache_destroy(se_sess_cache);
kmem_cache_destroy(se_ua_cache);
kmem_cache_destroy(t10_pr_reg_cache);
kmem_cache_destroy(t10_alua_lu_gp_cache);
kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
}
/* This code ensures unique mib indexes are handed out. */
static DEFINE_SPINLOCK(scsi_mib_index_lock);
static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
/*
* Allocate a new row index for the entry type specified
*/
u32 scsi_get_new_index(scsi_index_t type)
{
u32 new_index;
BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
spin_lock(&scsi_mib_index_lock);
new_index = ++scsi_mib_index[type];
spin_unlock(&scsi_mib_index_lock);
return new_index;
}
static void transport_init_queue_obj(struct se_queue_obj *qobj)
{
atomic_set(&qobj->queue_cnt, 0);
INIT_LIST_HEAD(&qobj->qobj_list);
init_waitqueue_head(&qobj->thread_wq);
spin_lock_init(&qobj->cmd_queue_lock);
}
void transport_subsystem_check_init(void)
{
int ret;
if (sub_api_initialized)
return;
ret = request_module("target_core_iblock");
if (ret != 0)
pr_err("Unable to load target_core_iblock\n");
ret = request_module("target_core_file");
if (ret != 0)
pr_err("Unable to load target_core_file\n");
ret = request_module("target_core_pscsi");
if (ret != 0)
pr_err("Unable to load target_core_pscsi\n");
ret = request_module("target_core_stgt");
if (ret != 0)
pr_err("Unable to load target_core_stgt\n");
sub_api_initialized = 1;
return;
}
struct se_session *transport_init_session(void)
{
struct se_session *se_sess;
se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
if (!se_sess) {
pr_err("Unable to allocate struct se_session from"
" se_sess_cache\n");
return ERR_PTR(-ENOMEM);
}
INIT_LIST_HEAD(&se_sess->sess_list);
INIT_LIST_HEAD(&se_sess->sess_acl_list);
INIT_LIST_HEAD(&se_sess->sess_cmd_list);
INIT_LIST_HEAD(&se_sess->sess_wait_list);
spin_lock_init(&se_sess->sess_cmd_lock);
return se_sess;
}
EXPORT_SYMBOL(transport_init_session);
/*
* Called with spin_lock_bh(&struct se_portal_group->session_lock called.
*/
void __transport_register_session(
struct se_portal_group *se_tpg,
struct se_node_acl *se_nacl,
struct se_session *se_sess,
void *fabric_sess_ptr)
{
unsigned char buf[PR_REG_ISID_LEN];
se_sess->se_tpg = se_tpg;
se_sess->fabric_sess_ptr = fabric_sess_ptr;
/*
* Used by struct se_node_acl's under ConfigFS to locate active se_session-t
*
* Only set for struct se_session's that will actually be moving I/O.
* eg: *NOT* discovery sessions.
*/
if (se_nacl) {
/*
* If the fabric module supports an ISID based TransportID,
* save this value in binary from the fabric I_T Nexus now.
*/
if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
memset(&buf[0], 0, PR_REG_ISID_LEN);
se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
&buf[0], PR_REG_ISID_LEN);
se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
}
spin_lock_irq(&se_nacl->nacl_sess_lock);
/*
* The se_nacl->nacl_sess pointer will be set to the
* last active I_T Nexus for each struct se_node_acl.
*/
se_nacl->nacl_sess = se_sess;
list_add_tail(&se_sess->sess_acl_list,
&se_nacl->acl_sess_list);
spin_unlock_irq(&se_nacl->nacl_sess_lock);
}
list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
}
EXPORT_SYMBOL(__transport_register_session);
void transport_register_session(
struct se_portal_group *se_tpg,
struct se_node_acl *se_nacl,
struct se_session *se_sess,
void *fabric_sess_ptr)
{
spin_lock_bh(&se_tpg->session_lock);
__transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
spin_unlock_bh(&se_tpg->session_lock);
}
EXPORT_SYMBOL(transport_register_session);
void transport_deregister_session_configfs(struct se_session *se_sess)
{
struct se_node_acl *se_nacl;
unsigned long flags;
/*
* Used by struct se_node_acl's under ConfigFS to locate active struct se_session
*/
se_nacl = se_sess->se_node_acl;
if (se_nacl) {
spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
list_del(&se_sess->sess_acl_list);
/*
* If the session list is empty, then clear the pointer.
* Otherwise, set the struct se_session pointer from the tail
* element of the per struct se_node_acl active session list.
*/
if (list_empty(&se_nacl->acl_sess_list))
se_nacl->nacl_sess = NULL;
else {
se_nacl->nacl_sess = container_of(
se_nacl->acl_sess_list.prev,
struct se_session, sess_acl_list);
}
spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
}
}
EXPORT_SYMBOL(transport_deregister_session_configfs);
void transport_free_session(struct se_session *se_sess)
{
kmem_cache_free(se_sess_cache, se_sess);
}
EXPORT_SYMBOL(transport_free_session);
void transport_deregister_session(struct se_session *se_sess)
{
struct se_portal_group *se_tpg = se_sess->se_tpg;
struct se_node_acl *se_nacl;
unsigned long flags;
if (!se_tpg) {
transport_free_session(se_sess);
return;
}
spin_lock_irqsave(&se_tpg->session_lock, flags);
list_del(&se_sess->sess_list);
se_sess->se_tpg = NULL;
se_sess->fabric_sess_ptr = NULL;
spin_unlock_irqrestore(&se_tpg->session_lock, flags);
/*
* Determine if we need to do extra work for this initiator node's
* struct se_node_acl if it had been previously dynamically generated.
*/
se_nacl = se_sess->se_node_acl;
if (se_nacl) {
spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
if (se_nacl->dynamic_node_acl) {
if (!se_tpg->se_tpg_tfo->tpg_check_demo_mode_cache(
se_tpg)) {
list_del(&se_nacl->acl_list);
se_tpg->num_node_acls--;
spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
core_tpg_wait_for_nacl_pr_ref(se_nacl);
core_free_device_list_for_node(se_nacl, se_tpg);
se_tpg->se_tpg_tfo->tpg_release_fabric_acl(se_tpg,
se_nacl);
spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
}
}
spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
}
transport_free_session(se_sess);
pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
se_tpg->se_tpg_tfo->get_fabric_name());
}
EXPORT_SYMBOL(transport_deregister_session);
/*
* Called with cmd->t_state_lock held.
*/
static void transport_all_task_dev_remove_state(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
struct se_task *task;
unsigned long flags;
if (!dev)
return;
list_for_each_entry(task, &cmd->t_task_list, t_list) {
if (task->task_flags & TF_ACTIVE)
continue;
spin_lock_irqsave(&dev->execute_task_lock, flags);
if (task->t_state_active) {
pr_debug("Removed ITT: 0x%08x dev: %p task[%p]\n",
cmd->se_tfo->get_task_tag(cmd), dev, task);
list_del(&task->t_state_list);
atomic_dec(&cmd->t_task_cdbs_ex_left);
task->t_state_active = false;
}
spin_unlock_irqrestore(&dev->execute_task_lock, flags);
}
}
/* transport_cmd_check_stop():
*
* 'transport_off = 1' determines if t_transport_active should be cleared.
* 'transport_off = 2' determines if task_dev_state should be removed.
*
* A non-zero u8 t_state sets cmd->t_state.
* Returns 1 when command is stopped, else 0.
*/
static int transport_cmd_check_stop(
struct se_cmd *cmd,
int transport_off,
u8 t_state)
{
unsigned long flags;
spin_lock_irqsave(&cmd->t_state_lock, flags);
/*
* Determine if IOCTL context caller in requesting the stopping of this
* command for LUN shutdown purposes.
*/
if (atomic_read(&cmd->transport_lun_stop)) {
pr_debug("%s:%d atomic_read(&cmd->transport_lun_stop)"
" == TRUE for ITT: 0x%08x\n", __func__, __LINE__,
cmd->se_tfo->get_task_tag(cmd));
atomic_set(&cmd->t_transport_active, 0);
if (transport_off == 2)
transport_all_task_dev_remove_state(cmd);
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
complete(&cmd->transport_lun_stop_comp);
return 1;
}
/*
* Determine if frontend context caller is requesting the stopping of
* this command for frontend exceptions.
*/
if (atomic_read(&cmd->t_transport_stop)) {
pr_debug("%s:%d atomic_read(&cmd->t_transport_stop) =="
" TRUE for ITT: 0x%08x\n", __func__, __LINE__,
cmd->se_tfo->get_task_tag(cmd));
if (transport_off == 2)
transport_all_task_dev_remove_state(cmd);
/*
* Clear struct se_cmd->se_lun before the transport_off == 2 handoff
* to FE.
*/
if (transport_off == 2)
cmd->se_lun = NULL;
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
complete(&cmd->t_transport_stop_comp);
return 1;
}
if (transport_off) {
atomic_set(&cmd->t_transport_active, 0);
if (transport_off == 2) {
transport_all_task_dev_remove_state(cmd);
/*
* Clear struct se_cmd->se_lun before the transport_off == 2
* handoff to fabric module.
*/
cmd->se_lun = NULL;
/*
* Some fabric modules like tcm_loop can release
* their internally allocated I/O reference now and
* struct se_cmd now.
*
* Fabric modules are expected to return '1' here if the
* se_cmd being passed is released at this point,
* or zero if not being released.
*/
if (cmd->se_tfo->check_stop_free != NULL) {
spin_unlock_irqrestore(
&cmd->t_state_lock, flags);
return cmd->se_tfo->check_stop_free(cmd);
}
}
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return 0;
} else if (t_state)
cmd->t_state = t_state;
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return 0;
}
static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
{
return transport_cmd_check_stop(cmd, 2, 0);
}
static void transport_lun_remove_cmd(struct se_cmd *cmd)
{
struct se_lun *lun = cmd->se_lun;
unsigned long flags;
if (!lun)
return;
spin_lock_irqsave(&cmd->t_state_lock, flags);
if (!atomic_read(&cmd->transport_dev_active)) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
goto check_lun;
}
atomic_set(&cmd->transport_dev_active, 0);
transport_all_task_dev_remove_state(cmd);
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
check_lun:
spin_lock_irqsave(&lun->lun_cmd_lock, flags);
if (atomic_read(&cmd->transport_lun_active)) {
list_del(&cmd->se_lun_node);
atomic_set(&cmd->transport_lun_active, 0);
#if 0
pr_debug("Removed ITT: 0x%08x from LUN LIST[%d]\n"
cmd->se_tfo->get_task_tag(cmd), lun->unpacked_lun);
#endif
}
spin_unlock_irqrestore(&lun->lun_cmd_lock, flags);
}
void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
{
if (!cmd->se_tmr_req)
transport_lun_remove_cmd(cmd);
if (transport_cmd_check_stop_to_fabric(cmd))
return;
if (remove) {
transport_remove_cmd_from_queue(cmd);
transport_put_cmd(cmd);
}
}
static void transport_add_cmd_to_queue(struct se_cmd *cmd, int t_state,
bool at_head)
{
struct se_device *dev = cmd->se_dev;
struct se_queue_obj *qobj = &dev->dev_queue_obj;
unsigned long flags;
if (t_state) {
spin_lock_irqsave(&cmd->t_state_lock, flags);
cmd->t_state = t_state;
atomic_set(&cmd->t_transport_active, 1);
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
}
spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
/* If the cmd is already on the list, remove it before we add it */
if (!list_empty(&cmd->se_queue_node))
list_del(&cmd->se_queue_node);
else
atomic_inc(&qobj->queue_cnt);
if (at_head)
list_add(&cmd->se_queue_node, &qobj->qobj_list);
else
list_add_tail(&cmd->se_queue_node, &qobj->qobj_list);
atomic_set(&cmd->t_transport_queue_active, 1);
spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
wake_up_interruptible(&qobj->thread_wq);
}
static struct se_cmd *
transport_get_cmd_from_queue(struct se_queue_obj *qobj)
{
struct se_cmd *cmd;
unsigned long flags;
spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
if (list_empty(&qobj->qobj_list)) {
spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
return NULL;
}
cmd = list_first_entry(&qobj->qobj_list, struct se_cmd, se_queue_node);
atomic_set(&cmd->t_transport_queue_active, 0);
list_del_init(&cmd->se_queue_node);
atomic_dec(&qobj->queue_cnt);
spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
return cmd;
}
static void transport_remove_cmd_from_queue(struct se_cmd *cmd)
{
struct se_queue_obj *qobj = &cmd->se_dev->dev_queue_obj;
unsigned long flags;
spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
if (!atomic_read(&cmd->t_transport_queue_active)) {
spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
return;
}
atomic_set(&cmd->t_transport_queue_active, 0);
atomic_dec(&qobj->queue_cnt);
list_del_init(&cmd->se_queue_node);
spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
if (atomic_read(&cmd->t_transport_queue_active)) {
pr_err("ITT: 0x%08x t_transport_queue_active: %d\n",
cmd->se_tfo->get_task_tag(cmd),
atomic_read(&cmd->t_transport_queue_active));
}
}
/*
* Completion function used by TCM subsystem plugins (such as FILEIO)
* for queueing up response from struct se_subsystem_api->do_task()
*/
void transport_complete_sync_cache(struct se_cmd *cmd, int good)
{
struct se_task *task = list_entry(cmd->t_task_list.next,
struct se_task, t_list);
if (good) {
cmd->scsi_status = SAM_STAT_GOOD;
task->task_scsi_status = GOOD;
} else {
task->task_scsi_status = SAM_STAT_CHECK_CONDITION;
task->task_se_cmd->scsi_sense_reason =
TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
transport_complete_task(task, good);
}
EXPORT_SYMBOL(transport_complete_sync_cache);
static void target_complete_failure_work(struct work_struct *work)
{
struct se_cmd *cmd = container_of(work, struct se_cmd, work);
transport_generic_request_failure(cmd);
}
/* transport_complete_task():
*
* Called from interrupt and non interrupt context depending
* on the transport plugin.
*/
void transport_complete_task(struct se_task *task, int success)
{
struct se_cmd *cmd = task->task_se_cmd;
struct se_device *dev = cmd->se_dev;
unsigned long flags;
spin_lock_irqsave(&cmd->t_state_lock, flags);
task->task_flags &= ~TF_ACTIVE;
/*
* See if any sense data exists, if so set the TASK_SENSE flag.
* Also check for any other post completion work that needs to be
* done by the plugins.
*/
if (dev && dev->transport->transport_complete) {
if (dev->transport->transport_complete(task) != 0) {
cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
task->task_flags |= TF_HAS_SENSE;
success = 1;
}
}
/*
* See if we are waiting for outstanding struct se_task
* to complete for an exception condition
*/
if (task->task_flags & TF_REQUEST_STOP) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
complete(&task->task_stop_comp);
return;
}
if (!success)
cmd->t_tasks_failed = 1;
/*
* Decrement the outstanding t_task_cdbs_left count. The last
* struct se_task from struct se_cmd will complete itself into the
* device queue depending upon int success.
*/
if (!atomic_dec_and_test(&cmd->t_task_cdbs_left)) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return;
}
if (cmd->t_tasks_failed) {
cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
INIT_WORK(&cmd->work, target_complete_failure_work);
} else {
atomic_set(&cmd->t_transport_complete, 1);
INIT_WORK(&cmd->work, target_complete_ok_work);
}
cmd->t_state = TRANSPORT_COMPLETE;
atomic_set(&cmd->t_transport_active, 1);
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
queue_work(target_completion_wq, &cmd->work);
}
EXPORT_SYMBOL(transport_complete_task);
/*
* Called by transport_add_tasks_from_cmd() once a struct se_cmd's
* struct se_task list are ready to be added to the active execution list
* struct se_device
* Called with se_dev_t->execute_task_lock called.
*/
static inline int transport_add_task_check_sam_attr(
struct se_task *task,
struct se_task *task_prev,
struct se_device *dev)
{
/*
* No SAM Task attribute emulation enabled, add to tail of
* execution queue
*/
if (dev->dev_task_attr_type != SAM_TASK_ATTR_EMULATED) {
list_add_tail(&task->t_execute_list, &dev->execute_task_list);
return 0;
}
/*
* HEAD_OF_QUEUE attribute for received CDB, which means
* the first task that is associated with a struct se_cmd goes to
* head of the struct se_device->execute_task_list, and task_prev
* after that for each subsequent task
*/
if (task->task_se_cmd->sam_task_attr == MSG_HEAD_TAG) {
list_add(&task->t_execute_list,
(task_prev != NULL) ?
&task_prev->t_execute_list :
&dev->execute_task_list);
pr_debug("Set HEAD_OF_QUEUE for task CDB: 0x%02x"
" in execution queue\n",
task->task_se_cmd->t_task_cdb[0]);
return 1;
}
/*
* For ORDERED, SIMPLE or UNTAGGED attribute tasks once they have been
* transitioned from Dermant -> Active state, and are added to the end
* of the struct se_device->execute_task_list
*/
list_add_tail(&task->t_execute_list, &dev->execute_task_list);
return 0;
}
/* __transport_add_task_to_execute_queue():
*
* Called with se_dev_t->execute_task_lock called.
*/
static void __transport_add_task_to_execute_queue(
struct se_task *task,
struct se_task *task_prev,
struct se_device *dev)
{
int head_of_queue;
head_of_queue = transport_add_task_check_sam_attr(task, task_prev, dev);
atomic_inc(&dev->execute_tasks);
if (task->t_state_active)
return;
/*
* Determine if this task needs to go to HEAD_OF_QUEUE for the
* state list as well. Running with SAM Task Attribute emulation
* will always return head_of_queue == 0 here
*/
if (head_of_queue)
list_add(&task->t_state_list, (task_prev) ?
&task_prev->t_state_list :
&dev->state_task_list);
else
list_add_tail(&task->t_state_list, &dev->state_task_list);
task->t_state_active = true;
pr_debug("Added ITT: 0x%08x task[%p] to dev: %p\n",
task->task_se_cmd->se_tfo->get_task_tag(task->task_se_cmd),
task, dev);
}
static void transport_add_tasks_to_state_queue(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
struct se_task *task;
unsigned long flags;
spin_lock_irqsave(&cmd->t_state_lock, flags);
list_for_each_entry(task, &cmd->t_task_list, t_list) {
spin_lock(&dev->execute_task_lock);
if (!task->t_state_active) {
list_add_tail(&task->t_state_list,
&dev->state_task_list);
task->t_state_active = true;
pr_debug("Added ITT: 0x%08x task[%p] to dev: %p\n",
task->task_se_cmd->se_tfo->get_task_tag(
task->task_se_cmd), task, dev);
}
spin_unlock(&dev->execute_task_lock);
}
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
}
static void __transport_add_tasks_from_cmd(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
struct se_task *task, *task_prev = NULL;
list_for_each_entry(task, &cmd->t_task_list, t_list) {
if (!list_empty(&task->t_execute_list))
continue;
/*
* __transport_add_task_to_execute_queue() handles the
* SAM Task Attribute emulation if enabled
*/
__transport_add_task_to_execute_queue(task, task_prev, dev);
task_prev = task;
}
}
static void transport_add_tasks_from_cmd(struct se_cmd *cmd)
{
unsigned long flags;
struct se_device *dev = cmd->se_dev;
spin_lock_irqsave(&dev->execute_task_lock, flags);
__transport_add_tasks_from_cmd(cmd);
spin_unlock_irqrestore(&dev->execute_task_lock, flags);
}
void __transport_remove_task_from_execute_queue(struct se_task *task,
struct se_device *dev)
{
list_del_init(&task->t_execute_list);
atomic_dec(&dev->execute_tasks);
}
static void transport_remove_task_from_execute_queue(
struct se_task *task,
struct se_device *dev)
{
unsigned long flags;
if (WARN_ON(list_empty(&task->t_execute_list)))
return;
spin_lock_irqsave(&dev->execute_task_lock, flags);
__transport_remove_task_from_execute_queue(task, dev);
spin_unlock_irqrestore(&dev->execute_task_lock, flags);
}
/*
* Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
*/
static void target_qf_do_work(struct work_struct *work)
{
struct se_device *dev = container_of(work, struct se_device,
qf_work_queue);
LIST_HEAD(qf_cmd_list);
struct se_cmd *cmd, *cmd_tmp;
spin_lock_irq(&dev->qf_cmd_lock);
list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
spin_unlock_irq(&dev->qf_cmd_lock);
list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
list_del(&cmd->se_qf_node);
atomic_dec(&dev->dev_qf_count);
smp_mb__after_atomic_dec();
pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
" context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
(cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
(cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
: "UNKNOWN");
transport_add_cmd_to_queue(cmd, cmd->t_state, true);
}
}
unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
{
switch (cmd->data_direction) {
case DMA_NONE:
return "NONE";
case DMA_FROM_DEVICE:
return "READ";
case DMA_TO_DEVICE:
return "WRITE";
case DMA_BIDIRECTIONAL:
return "BIDI";
default:
break;
}
return "UNKNOWN";
}
void transport_dump_dev_state(
struct se_device *dev,
char *b,
int *bl)
{
*bl += sprintf(b + *bl, "Status: ");
switch (dev->dev_status) {
case TRANSPORT_DEVICE_ACTIVATED:
*bl += sprintf(b + *bl, "ACTIVATED");
break;
case TRANSPORT_DEVICE_DEACTIVATED:
*bl += sprintf(b + *bl, "DEACTIVATED");
break;
case TRANSPORT_DEVICE_SHUTDOWN:
*bl += sprintf(b + *bl, "SHUTDOWN");
break;
case TRANSPORT_DEVICE_OFFLINE_ACTIVATED:
case TRANSPORT_DEVICE_OFFLINE_DEACTIVATED:
*bl += sprintf(b + *bl, "OFFLINE");
break;
default:
*bl += sprintf(b + *bl, "UNKNOWN=%d", dev->dev_status);
break;
}
*bl += sprintf(b + *bl, " Execute/Max Queue Depth: %d/%d",
atomic_read(&dev->execute_tasks), dev->queue_depth);
*bl += sprintf(b + *bl, " SectorSize: %u MaxSectors: %u\n",
dev->se_sub_dev->se_dev_attrib.block_size, dev->se_sub_dev->se_dev_attrib.max_sectors);
*bl += sprintf(b + *bl, " ");
}
void transport_dump_vpd_proto_id(
struct t10_vpd *vpd,
unsigned char *p_buf,
int p_buf_len)
{
unsigned char buf[VPD_TMP_BUF_SIZE];
int len;
memset(buf, 0, VPD_TMP_BUF_SIZE);
len = sprintf(buf, "T10 VPD Protocol Identifier: ");
switch (vpd->protocol_identifier) {
case 0x00:
sprintf(buf+len, "Fibre Channel\n");
break;
case 0x10:
sprintf(buf+len, "Parallel SCSI\n");
break;
case 0x20:
sprintf(buf+len, "SSA\n");
break;
case 0x30:
sprintf(buf+len, "IEEE 1394\n");
break;
case 0x40:
sprintf(buf+len, "SCSI Remote Direct Memory Access"
" Protocol\n");
break;
case 0x50:
sprintf(buf+len, "Internet SCSI (iSCSI)\n");
break;
case 0x60:
sprintf(buf+len, "SAS Serial SCSI Protocol\n");
break;
case 0x70:
sprintf(buf+len, "Automation/Drive Interface Transport"
" Protocol\n");
break;
case 0x80:
sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
break;
default:
sprintf(buf+len, "Unknown 0x%02x\n",
vpd->protocol_identifier);
break;
}
if (p_buf)
strncpy(p_buf, buf, p_buf_len);
else
pr_debug("%s", buf);
}
void
transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
{
/*
* Check if the Protocol Identifier Valid (PIV) bit is set..
*
* from spc3r23.pdf section 7.5.1
*/
if (page_83[1] & 0x80) {
vpd->protocol_identifier = (page_83[0] & 0xf0);
vpd->protocol_identifier_set = 1;
transport_dump_vpd_proto_id(vpd, NULL, 0);
}
}
EXPORT_SYMBOL(transport_set_vpd_proto_id);
int transport_dump_vpd_assoc(
struct t10_vpd *vpd,
unsigned char *p_buf,
int p_buf_len)
{
unsigned char buf[VPD_TMP_BUF_SIZE];
int ret = 0;
int len;
memset(buf, 0, VPD_TMP_BUF_SIZE);
len = sprintf(buf, "T10 VPD Identifier Association: ");
switch (vpd->association) {
case 0x00:
sprintf(buf+len, "addressed logical unit\n");
break;
case 0x10:
sprintf(buf+len, "target port\n");
break;
case 0x20:
sprintf(buf+len, "SCSI target device\n");
break;
default:
sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
ret = -EINVAL;
break;
}
if (p_buf)
strncpy(p_buf, buf, p_buf_len);
else
pr_debug("%s", buf);
return ret;
}
int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
{
/*
* The VPD identification association..
*
* from spc3r23.pdf Section 7.6.3.1 Table 297
*/
vpd->association = (page_83[1] & 0x30);
return transport_dump_vpd_assoc(vpd, NULL, 0);
}
EXPORT_SYMBOL(transport_set_vpd_assoc);
int transport_dump_vpd_ident_type(
struct t10_vpd *vpd,
unsigned char *p_buf,
int p_buf_len)
{
unsigned char buf[VPD_TMP_BUF_SIZE];
int ret = 0;
int len;
memset(buf, 0, VPD_TMP_BUF_SIZE);
len = sprintf(buf, "T10 VPD Identifier Type: ");
switch (vpd->device_identifier_type) {
case 0x00:
sprintf(buf+len, "Vendor specific\n");
break;
case 0x01:
sprintf(buf+len, "T10 Vendor ID based\n");
break;
case 0x02:
sprintf(buf+len, "EUI-64 based\n");
break;
case 0x03:
sprintf(buf+len, "NAA\n");
break;
case 0x04:
sprintf(buf+len, "Relative target port identifier\n");
break;
case 0x08:
sprintf(buf+len, "SCSI name string\n");
break;
default:
sprintf(buf+len, "Unsupported: 0x%02x\n",
vpd->device_identifier_type);
ret = -EINVAL;
break;
}
if (p_buf) {
if (p_buf_len < strlen(buf)+1)
return -EINVAL;
strncpy(p_buf, buf, p_buf_len);
} else {
pr_debug("%s", buf);
}
return ret;
}
int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
{
/*
* The VPD identifier type..
*
* from spc3r23.pdf Section 7.6.3.1 Table 298
*/
vpd->device_identifier_type = (page_83[1] & 0x0f);
return transport_dump_vpd_ident_type(vpd, NULL, 0);
}
EXPORT_SYMBOL(transport_set_vpd_ident_type);
int transport_dump_vpd_ident(
struct t10_vpd *vpd,
unsigned char *p_buf,
int p_buf_len)
{
unsigned char buf[VPD_TMP_BUF_SIZE];
int ret = 0;
memset(buf, 0, VPD_TMP_BUF_SIZE);
switch (vpd->device_identifier_code_set) {
case 0x01: /* Binary */
sprintf(buf, "T10 VPD Binary Device Identifier: %s\n",
&vpd->device_identifier[0]);
break;
case 0x02: /* ASCII */
sprintf(buf, "T10 VPD ASCII Device Identifier: %s\n",
&vpd->device_identifier[0]);
break;
case 0x03: /* UTF-8 */
sprintf(buf, "T10 VPD UTF-8 Device Identifier: %s\n",
&vpd->device_identifier[0]);
break;
default:
sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
" 0x%02x", vpd->device_identifier_code_set);
ret = -EINVAL;
break;
}
if (p_buf)
strncpy(p_buf, buf, p_buf_len);
else
pr_debug("%s", buf);
return ret;
}
int
transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
{
static const char hex_str[] = "0123456789abcdef";
int j = 0, i = 4; /* offset to start of the identifer */
/*
* The VPD Code Set (encoding)
*
* from spc3r23.pdf Section 7.6.3.1 Table 296
*/
vpd->device_identifier_code_set = (page_83[0] & 0x0f);
switch (vpd->device_identifier_code_set) {
case 0x01: /* Binary */
vpd->device_identifier[j++] =
hex_str[vpd->device_identifier_type];
while (i < (4 + page_83[3])) {
vpd->device_identifier[j++] =
hex_str[(page_83[i] & 0xf0) >> 4];
vpd->device_identifier[j++] =
hex_str[page_83[i] & 0x0f];
i++;
}
break;
case 0x02: /* ASCII */
case 0x03: /* UTF-8 */
while (i < (4 + page_83[3]))
vpd->device_identifier[j++] = page_83[i++];
break;
default:
break;
}
return transport_dump_vpd_ident(vpd, NULL, 0);
}
EXPORT_SYMBOL(transport_set_vpd_ident);
static void core_setup_task_attr_emulation(struct se_device *dev)
{
/*
* If this device is from Target_Core_Mod/pSCSI, disable the
* SAM Task Attribute emulation.
*
* This is currently not available in upsream Linux/SCSI Target
* mode code, and is assumed to be disabled while using TCM/pSCSI.
*/
if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) {
dev->dev_task_attr_type = SAM_TASK_ATTR_PASSTHROUGH;
return;
}
dev->dev_task_attr_type = SAM_TASK_ATTR_EMULATED;
pr_debug("%s: Using SAM_TASK_ATTR_EMULATED for SPC: 0x%02x"
" device\n", dev->transport->name,
dev->transport->get_device_rev(dev));
}
static void scsi_dump_inquiry(struct se_device *dev)
{
struct t10_wwn *wwn = &dev->se_sub_dev->t10_wwn;
char buf[17];
int i, device_type;
/*
* Print Linux/SCSI style INQUIRY formatting to the kernel ring buffer
*/
for (i = 0; i < 8; i++)
if (wwn->vendor[i] >= 0x20)
buf[i] = wwn->vendor[i];
else
buf[i] = ' ';
buf[i] = '\0';
pr_debug(" Vendor: %s\n", buf);
for (i = 0; i < 16; i++)
if (wwn->model[i] >= 0x20)
buf[i] = wwn->model[i];
else
buf[i] = ' ';
buf[i] = '\0';
pr_debug(" Model: %s\n", buf);
for (i = 0; i < 4; i++)
if (wwn->revision[i] >= 0x20)
buf[i] = wwn->revision[i];
else
buf[i] = ' ';
buf[i] = '\0';
pr_debug(" Revision: %s\n", buf);
device_type = dev->transport->get_device_type(dev);
pr_debug(" Type: %s ", scsi_device_type(device_type));
pr_debug(" ANSI SCSI revision: %02x\n",
dev->transport->get_device_rev(dev));
}
struct se_device *transport_add_device_to_core_hba(
struct se_hba *hba,
struct se_subsystem_api *transport,
struct se_subsystem_dev *se_dev,
u32 device_flags,
void *transport_dev,
struct se_dev_limits *dev_limits,
const char *inquiry_prod,
const char *inquiry_rev)
{
int force_pt;
struct se_device *dev;
dev = kzalloc(sizeof(struct se_device), GFP_KERNEL);
if (!dev) {
pr_err("Unable to allocate memory for se_dev_t\n");
return NULL;
}
transport_init_queue_obj(&dev->dev_queue_obj);
dev->dev_flags = device_flags;
dev->dev_status |= TRANSPORT_DEVICE_DEACTIVATED;
dev->dev_ptr = transport_dev;
dev->se_hba = hba;
dev->se_sub_dev = se_dev;
dev->transport = transport;
INIT_LIST_HEAD(&dev->dev_list);
INIT_LIST_HEAD(&dev->dev_sep_list);
INIT_LIST_HEAD(&dev->dev_tmr_list);
INIT_LIST_HEAD(&dev->execute_task_list);
INIT_LIST_HEAD(&dev->delayed_cmd_list);
INIT_LIST_HEAD(&dev->state_task_list);
INIT_LIST_HEAD(&dev->qf_cmd_list);
spin_lock_init(&dev->execute_task_lock);
spin_lock_init(&dev->delayed_cmd_lock);
spin_lock_init(&dev->dev_reservation_lock);
spin_lock_init(&dev->dev_status_lock);
spin_lock_init(&dev->se_port_lock);
spin_lock_init(&dev->se_tmr_lock);
spin_lock_init(&dev->qf_cmd_lock);
atomic_set(&dev->dev_ordered_id, 0);
se_dev_set_default_attribs(dev, dev_limits);
dev->dev_index = scsi_get_new_index(SCSI_DEVICE_INDEX);
dev->creation_time = get_jiffies_64();
spin_lock_init(&dev->stats_lock);
spin_lock(&hba->device_lock);
list_add_tail(&dev->dev_list, &hba->hba_dev_list);
hba->dev_count++;
spin_unlock(&hba->device_lock);
/*
* Setup the SAM Task Attribute emulation for struct se_device
*/
core_setup_task_attr_emulation(dev);
/*
* Force PR and ALUA passthrough emulation with internal object use.
*/
force_pt = (hba->hba_flags & HBA_FLAGS_INTERNAL_USE);
/*
* Setup the Reservations infrastructure for struct se_device
*/
core_setup_reservations(dev, force_pt);
/*
* Setup the Asymmetric Logical Unit Assignment for struct se_device
*/
if (core_setup_alua(dev, force_pt) < 0)
goto out;
/*
* Startup the struct se_device processing thread
*/
dev->process_thread = kthread_run(transport_processing_thread, dev,
"LIO_%s", dev->transport->name);
if (IS_ERR(dev->process_thread)) {
pr_err("Unable to create kthread: LIO_%s\n",
dev->transport->name);
goto out;
}
/*
* Setup work_queue for QUEUE_FULL
*/
INIT_WORK(&dev->qf_work_queue, target_qf_do_work);
/*
* Preload the initial INQUIRY const values if we are doing
* anything virtual (IBLOCK, FILEIO, RAMDISK), but not for TCM/pSCSI
* passthrough because this is being provided by the backend LLD.
* This is required so that transport_get_inquiry() copies these
* originals once back into DEV_T10_WWN(dev) for the virtual device
* setup.
*/
if (dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV) {
if (!inquiry_prod || !inquiry_rev) {
pr_err("All non TCM/pSCSI plugins require"
" INQUIRY consts\n");
goto out;
}
strncpy(&dev->se_sub_dev->t10_wwn.vendor[0], "LIO-ORG", 8);
strncpy(&dev->se_sub_dev->t10_wwn.model[0], inquiry_prod, 16);
strncpy(&dev->se_sub_dev->t10_wwn.revision[0], inquiry_rev, 4);
}
scsi_dump_inquiry(dev);
return dev;
out:
kthread_stop(dev->process_thread);
spin_lock(&hba->device_lock);
list_del(&dev->dev_list);
hba->dev_count--;
spin_unlock(&hba->device_lock);
se_release_vpd_for_dev(dev);
kfree(dev);
return NULL;
}
EXPORT_SYMBOL(transport_add_device_to_core_hba);
/* transport_generic_prepare_cdb():
*
* Since the Initiator sees iSCSI devices as LUNs, the SCSI CDB will
* contain the iSCSI LUN in bits 7-5 of byte 1 as per SAM-2.
* The point of this is since we are mapping iSCSI LUNs to
* SCSI Target IDs having a non-zero LUN in the CDB will throw the
* devices and HBAs for a loop.
*/
static inline void transport_generic_prepare_cdb(
unsigned char *cdb)
{
switch (cdb[0]) {
case READ_10: /* SBC - RDProtect */
case READ_12: /* SBC - RDProtect */
case READ_16: /* SBC - RDProtect */
case SEND_DIAGNOSTIC: /* SPC - SELF-TEST Code */
case VERIFY: /* SBC - VRProtect */
case VERIFY_16: /* SBC - VRProtect */
case WRITE_VERIFY: /* SBC - VRProtect */
case WRITE_VERIFY_12: /* SBC - VRProtect */
break;
default:
cdb[1] &= 0x1f; /* clear logical unit number */
break;
}
}
static struct se_task *
transport_generic_get_task(struct se_cmd *cmd,
enum dma_data_direction data_direction)
{
struct se_task *task;
struct se_device *dev = cmd->se_dev;
task = dev->transport->alloc_task(cmd->t_task_cdb);
if (!task) {
pr_err("Unable to allocate struct se_task\n");
return NULL;
}
INIT_LIST_HEAD(&task->t_list);
INIT_LIST_HEAD(&task->t_execute_list);
INIT_LIST_HEAD(&task->t_state_list);
init_completion(&task->task_stop_comp);
task->task_se_cmd = cmd;
task->task_data_direction = data_direction;
return task;
}
static int transport_generic_cmd_sequencer(struct se_cmd *, unsigned char *);
/*
* Used by fabric modules containing a local struct se_cmd within their
* fabric dependent per I/O descriptor.
*/
void transport_init_se_cmd(
struct se_cmd *cmd,
struct target_core_fabric_ops *tfo,
struct se_session *se_sess,
u32 data_length,
int data_direction,
int task_attr,
unsigned char *sense_buffer)
{
INIT_LIST_HEAD(&cmd->se_lun_node);
INIT_LIST_HEAD(&cmd->se_delayed_node);
INIT_LIST_HEAD(&cmd->se_qf_node);
INIT_LIST_HEAD(&cmd->se_queue_node);
INIT_LIST_HEAD(&cmd->se_cmd_list);
INIT_LIST_HEAD(&cmd->t_task_list);
init_completion(&cmd->transport_lun_fe_stop_comp);
init_completion(&cmd->transport_lun_stop_comp);
init_completion(&cmd->t_transport_stop_comp);
init_completion(&cmd->cmd_wait_comp);
spin_lock_init(&cmd->t_state_lock);
atomic_set(&cmd->transport_dev_active, 1);
cmd->se_tfo = tfo;
cmd->se_sess = se_sess;
cmd->data_length = data_length;
cmd->data_direction = data_direction;
cmd->sam_task_attr = task_attr;
cmd->sense_buffer = sense_buffer;
}
EXPORT_SYMBOL(transport_init_se_cmd);
static int transport_check_alloc_task_attr(struct se_cmd *cmd)
{
/*
* Check if SAM Task Attribute emulation is enabled for this
* struct se_device storage object
*/
if (cmd->se_dev->dev_task_attr_type != SAM_TASK_ATTR_EMULATED)
return 0;
if (cmd->sam_task_attr == MSG_ACA_TAG) {
pr_debug("SAM Task Attribute ACA"
" emulation is not supported\n");
return -EINVAL;
}
/*
* Used to determine when ORDERED commands should go from
* Dormant to Active status.
*/
cmd->se_ordered_id = atomic_inc_return(&cmd->se_dev->dev_ordered_id);
smp_mb__after_atomic_inc();
pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
cmd->se_ordered_id, cmd->sam_task_attr,
cmd->se_dev->transport->name);
return 0;
}
/* transport_generic_allocate_tasks():
*
* Called from fabric RX Thread.
*/
int transport_generic_allocate_tasks(
struct se_cmd *cmd,
unsigned char *cdb)
{
int ret;
transport_generic_prepare_cdb(cdb);
/*
* Ensure that the received CDB is less than the max (252 + 8) bytes
* for VARIABLE_LENGTH_CMD
*/
if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
pr_err("Received SCSI CDB with command_size: %d that"
" exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
return -EINVAL;
}
/*
* If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
* allocate the additional extended CDB buffer now.. Otherwise
* setup the pointer from __t_task_cdb to t_task_cdb.
*/
if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
GFP_KERNEL);
if (!cmd->t_task_cdb) {
pr_err("Unable to allocate cmd->t_task_cdb"
" %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
scsi_command_size(cdb),
(unsigned long)sizeof(cmd->__t_task_cdb));
cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
cmd->scsi_sense_reason =
TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
return -ENOMEM;
}
} else
cmd->t_task_cdb = &cmd->__t_task_cdb[0];
/*
* Copy the original CDB into cmd->
*/
memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
/*
* Setup the received CDB based on SCSI defined opcodes and
* perform unit attention, persistent reservations and ALUA
* checks for virtual device backends. The cmd->t_task_cdb
* pointer is expected to be setup before we reach this point.
*/
ret = transport_generic_cmd_sequencer(cmd, cdb);
if (ret < 0)
return ret;
/*
* Check for SAM Task Attribute Emulation
*/
if (transport_check_alloc_task_attr(cmd) < 0) {
cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
return -EINVAL;
}
spin_lock(&cmd->se_lun->lun_sep_lock);
if (cmd->se_lun->lun_sep)
cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
spin_unlock(&cmd->se_lun->lun_sep_lock);
return 0;
}
EXPORT_SYMBOL(transport_generic_allocate_tasks);
/*
* Used by fabric module frontends to queue tasks directly.
* Many only be used from process context only
*/
int transport_handle_cdb_direct(
struct se_cmd *cmd)
{
int ret;
if (!cmd->se_lun) {
dump_stack();
pr_err("cmd->se_lun is NULL\n");
return -EINVAL;
}
if (in_interrupt()) {
dump_stack();
pr_err("transport_generic_handle_cdb cannot be called"
" from interrupt context\n");
return -EINVAL;
}
/*
* Set TRANSPORT_NEW_CMD state and cmd->t_transport_active=1 following
* transport_generic_handle_cdb*() -> transport_add_cmd_to_queue()
* in existing usage to ensure that outstanding descriptors are handled
* correctly during shutdown via transport_wait_for_tasks()
*
* Also, we don't take cmd->t_state_lock here as we only expect
* this to be called for initial descriptor submission.
*/
cmd->t_state = TRANSPORT_NEW_CMD;
atomic_set(&cmd->t_transport_active, 1);
/*
* transport_generic_new_cmd() is already handling QUEUE_FULL,
* so follow TRANSPORT_NEW_CMD processing thread context usage
* and call transport_generic_request_failure() if necessary..
*/
ret = transport_generic_new_cmd(cmd);
if (ret < 0)
transport_generic_request_failure(cmd);
return 0;
}
EXPORT_SYMBOL(transport_handle_cdb_direct);
/**
* target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
*
* @se_cmd: command descriptor to submit
* @se_sess: associated se_sess for endpoint
* @cdb: pointer to SCSI CDB
* @sense: pointer to SCSI sense buffer
* @unpacked_lun: unpacked LUN to reference for struct se_lun
* @data_length: fabric expected data transfer length
* @task_addr: SAM task attribute
* @data_dir: DMA data direction
* @flags: flags for command submission from target_sc_flags_tables
*
* This may only be called from process context, and also currently
* assumes internal allocation of fabric payload buffer by target-core.
**/
void target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
u32 data_length, int task_attr, int data_dir, int flags)
{
struct se_portal_group *se_tpg;
int rc;
se_tpg = se_sess->se_tpg;
BUG_ON(!se_tpg);
BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
BUG_ON(in_interrupt());
/*
* Initialize se_cmd for target operation. From this point
* exceptions are handled by sending exception status via
* target_core_fabric_ops->queue_status() callback
*/
transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
data_length, data_dir, task_attr, sense);
/*
* Obtain struct se_cmd->cmd_kref reference and add new cmd to
* se_sess->sess_cmd_list. A second kref_get here is necessary
* for fabrics using TARGET_SCF_ACK_KREF that expect a second
* kref_put() to happen during fabric packet acknowledgement.
*/
target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
/*
* Signal bidirectional data payloads to target-core
*/
if (flags & TARGET_SCF_BIDI_OP)
se_cmd->se_cmd_flags |= SCF_BIDI;
/*
* Locate se_lun pointer and attach it to struct se_cmd
*/
if (transport_lookup_cmd_lun(se_cmd, unpacked_lun) < 0) {
transport_send_check_condition_and_sense(se_cmd,
se_cmd->scsi_sense_reason, 0);
target_put_sess_cmd(se_sess, se_cmd);
return;
}
/*
* Sanitize CDBs via transport_generic_cmd_sequencer() and
* allocate the necessary tasks to complete the received CDB+data
*/
rc = transport_generic_allocate_tasks(se_cmd, cdb);
if (rc != 0) {
transport_generic_request_failure(se_cmd);
return;
}
/*
* Dispatch se_cmd descriptor to se_lun->lun_se_dev backend
* for immediate execution of READs, otherwise wait for
* transport_generic_handle_data() to be called for WRITEs
* when fabric has filled the incoming buffer.
*/
transport_handle_cdb_direct(se_cmd);
return;
}
EXPORT_SYMBOL(target_submit_cmd);
/*
* Used by fabric module frontends defining a TFO->new_cmd_map() caller
* to queue up a newly setup se_cmd w/ TRANSPORT_NEW_CMD_MAP in order to
* complete setup in TCM process context w/ TFO->new_cmd_map().
*/
int transport_generic_handle_cdb_map(
struct se_cmd *cmd)
{
if (!cmd->se_lun) {
dump_stack();
pr_err("cmd->se_lun is NULL\n");
return -EINVAL;
}
transport_add_cmd_to_queue(cmd, TRANSPORT_NEW_CMD_MAP, false);
return 0;
}
EXPORT_SYMBOL(transport_generic_handle_cdb_map);
/* transport_generic_handle_data():
*
*
*/
int transport_generic_handle_data(
struct se_cmd *cmd)
{
/*
* For the software fabric case, then we assume the nexus is being
* failed/shutdown when signals are pending from the kthread context
* caller, so we return a failure. For the HW target mode case running
* in interrupt code, the signal_pending() check is skipped.
*/
if (!in_interrupt() && signal_pending(current))
return -EPERM;
/*
* If the received CDB has aleady been ABORTED by the generic
* target engine, we now call transport_check_aborted_status()
* to queue any delated TASK_ABORTED status for the received CDB to the
* fabric module as we are expecting no further incoming DATA OUT
* sequences at this point.
*/
if (transport_check_aborted_status(cmd, 1) != 0)
return 0;
transport_add_cmd_to_queue(cmd, TRANSPORT_PROCESS_WRITE, false);
return 0;
}
EXPORT_SYMBOL(transport_generic_handle_data);
/* transport_generic_handle_tmr():
*
*
*/
int transport_generic_handle_tmr(
struct se_cmd *cmd)
{
transport_add_cmd_to_queue(cmd, TRANSPORT_PROCESS_TMR, false);
return 0;
}
EXPORT_SYMBOL(transport_generic_handle_tmr);
/*
* If the task is active, request it to be stopped and sleep until it
* has completed.
*/
bool target_stop_task(struct se_task *task, unsigned long *flags)
{
struct se_cmd *cmd = task->task_se_cmd;
bool was_active = false;
if (task->task_flags & TF_ACTIVE) {
task->task_flags |= TF_REQUEST_STOP;
spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
pr_debug("Task %p waiting to complete\n", task);
wait_for_completion(&task->task_stop_comp);
pr_debug("Task %p stopped successfully\n", task);
spin_lock_irqsave(&cmd->t_state_lock, *flags);
atomic_dec(&cmd->t_task_cdbs_left);
task->task_flags &= ~(TF_ACTIVE | TF_REQUEST_STOP);
was_active = true;
}
return was_active;
}
static int transport_stop_tasks_for_cmd(struct se_cmd *cmd)
{
struct se_task *task, *task_tmp;
unsigned long flags;
int ret = 0;
pr_debug("ITT[0x%08x] - Stopping tasks\n",
cmd->se_tfo->get_task_tag(cmd));
/*
* No tasks remain in the execution queue
*/
spin_lock_irqsave(&cmd->t_state_lock, flags);
list_for_each_entry_safe(task, task_tmp,
&cmd->t_task_list, t_list) {
pr_debug("Processing task %p\n", task);
/*
* If the struct se_task has not been sent and is not active,
* remove the struct se_task from the execution queue.
*/
if (!(task->task_flags & (TF_ACTIVE | TF_SENT))) {
spin_unlock_irqrestore(&cmd->t_state_lock,
flags);
transport_remove_task_from_execute_queue(task,
cmd->se_dev);
pr_debug("Task %p removed from execute queue\n", task);
spin_lock_irqsave(&cmd->t_state_lock, flags);
continue;
}
if (!target_stop_task(task, &flags)) {
pr_debug("Task %p - did nothing\n", task);
ret++;
}
}
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return ret;
}
/*
* Handle SAM-esque emulation for generic transport request failures.
*/
static void transport_generic_request_failure(struct se_cmd *cmd)
{
int ret = 0;
pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
" CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
cmd->t_task_cdb[0]);
pr_debug("-----[ i_state: %d t_state: %d scsi_sense_reason: %d\n",
cmd->se_tfo->get_cmd_state(cmd),
cmd->t_state, cmd->scsi_sense_reason);
pr_debug("-----[ t_tasks: %d t_task_cdbs_left: %d"
" t_task_cdbs_sent: %d t_task_cdbs_ex_left: %d --"
" t_transport_active: %d t_transport_stop: %d"
" t_transport_sent: %d\n", cmd->t_task_list_num,
atomic_read(&cmd->t_task_cdbs_left),
atomic_read(&cmd->t_task_cdbs_sent),
atomic_read(&cmd->t_task_cdbs_ex_left),
atomic_read(&cmd->t_transport_active),
atomic_read(&cmd->t_transport_stop),
atomic_read(&cmd->t_transport_sent));
/*
* For SAM Task Attribute emulation for failed struct se_cmd
*/
if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
transport_complete_task_attr(cmd);
switch (cmd->scsi_sense_reason) {
case TCM_NON_EXISTENT_LUN:
case TCM_UNSUPPORTED_SCSI_OPCODE:
case TCM_INVALID_CDB_FIELD:
case TCM_INVALID_PARAMETER_LIST:
case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
case TCM_UNKNOWN_MODE_PAGE:
case TCM_WRITE_PROTECTED:
case TCM_CHECK_CONDITION_ABORT_CMD:
case TCM_CHECK_CONDITION_UNIT_ATTENTION:
case TCM_CHECK_CONDITION_NOT_READY:
break;
case TCM_RESERVATION_CONFLICT:
/*
* No SENSE Data payload for this case, set SCSI Status
* and queue the response to $FABRIC_MOD.
*
* Uses linux/include/scsi/scsi.h SAM status codes defs
*/
cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
/*
* For UA Interlock Code 11b, a RESERVATION CONFLICT will
* establish a UNIT ATTENTION with PREVIOUS RESERVATION
* CONFLICT STATUS.
*
* See spc4r17, section 7.4.6 Control Mode Page, Table 349
*/
if (cmd->se_sess &&
cmd->se_dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl == 2)
core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
cmd->orig_fe_lun, 0x2C,
ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
ret = cmd->se_tfo->queue_status(cmd);
if (ret == -EAGAIN || ret == -ENOMEM)
goto queue_full;
goto check_stop;
default:
pr_err("Unknown transport error for CDB 0x%02x: %d\n",
cmd->t_task_cdb[0], cmd->scsi_sense_reason);
cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
break;
}
/*
* If a fabric does not define a cmd->se_tfo->new_cmd_map caller,
* make the call to transport_send_check_condition_and_sense()
* directly. Otherwise expect the fabric to make the call to
* transport_send_check_condition_and_sense() after handling
* possible unsoliticied write data payloads.
*/
ret = transport_send_check_condition_and_sense(cmd,
cmd->scsi_sense_reason, 0);
if (ret == -EAGAIN || ret == -ENOMEM)
goto queue_full;
check_stop:
transport_lun_remove_cmd(cmd);
if (!transport_cmd_check_stop_to_fabric(cmd))
;
return;
queue_full:
cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
transport_handle_queue_full(cmd, cmd->se_dev);
}
static inline u32 transport_lba_21(unsigned char *cdb)
{
return ((cdb[1] & 0x1f) << 16) | (cdb[2] << 8) | cdb[3];
}
static inline u32 transport_lba_32(unsigned char *cdb)
{
return (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
}
static inline unsigned long long transport_lba_64(unsigned char *cdb)
{
unsigned int __v1, __v2;
__v1 = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
__v2 = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
}
/*
* For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
*/
static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
{
unsigned int __v1, __v2;
__v1 = (cdb[12] << 24) | (cdb[13] << 16) | (cdb[14] << 8) | cdb[15];
__v2 = (cdb[16] << 24) | (cdb[17] << 16) | (cdb[18] << 8) | cdb[19];
return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
}
static void transport_set_supported_SAM_opcode(struct se_cmd *se_cmd)
{
unsigned long flags;
spin_lock_irqsave(&se_cmd->t_state_lock, flags);
se_cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
}
/*
* Called from Fabric Module context from transport_execute_tasks()
*
* The return of this function determins if the tasks from struct se_cmd
* get added to the execution queue in transport_execute_tasks(),
* or are added to the delayed or ordered lists here.
*/
static inline int transport_execute_task_attr(struct se_cmd *cmd)
{
if (cmd->se_dev->dev_task_attr_type != SAM_TASK_ATTR_EMULATED)
return 1;
/*
* Check for the existence of HEAD_OF_QUEUE, and if true return 1
* to allow the passed struct se_cmd list of tasks to the front of the list.
*/
if (cmd->sam_task_attr == MSG_HEAD_TAG) {
pr_debug("Added HEAD_OF_QUEUE for CDB:"
" 0x%02x, se_ordered_id: %u\n",
cmd->t_task_cdb[0],
cmd->se_ordered_id);
return 1;
} else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
atomic_inc(&cmd->se_dev->dev_ordered_sync);
smp_mb__after_atomic_inc();
pr_debug("Added ORDERED for CDB: 0x%02x to ordered"
" list, se_ordered_id: %u\n",
cmd->t_task_cdb[0],
cmd->se_ordered_id);
/*
* Add ORDERED command to tail of execution queue if
* no other older commands exist that need to be
* completed first.
*/
if (!atomic_read(&cmd->se_dev->simple_cmds))
return 1;
} else {
/*
* For SIMPLE and UNTAGGED Task Attribute commands
*/
atomic_inc(&cmd->se_dev->simple_cmds);
smp_mb__after_atomic_inc();
}
/*
* Otherwise if one or more outstanding ORDERED task attribute exist,
* add the dormant task(s) built for the passed struct se_cmd to the
* execution queue and become in Active state for this struct se_device.
*/
if (atomic_read(&cmd->se_dev->dev_ordered_sync) != 0) {
/*
* Otherwise, add cmd w/ tasks to delayed cmd queue that
* will be drained upon completion of HEAD_OF_QUEUE task.
*/
spin_lock(&cmd->se_dev->delayed_cmd_lock);
cmd->se_cmd_flags |= SCF_DELAYED_CMD_FROM_SAM_ATTR;
list_add_tail(&cmd->se_delayed_node,
&cmd->se_dev->delayed_cmd_list);
spin_unlock(&cmd->se_dev->delayed_cmd_lock);
pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
" delayed CMD list, se_ordered_id: %u\n",
cmd->t_task_cdb[0], cmd->sam_task_attr,
cmd->se_ordered_id);
/*
* Return zero to let transport_execute_tasks() know
* not to add the delayed tasks to the execution list.
*/
return 0;
}
/*
* Otherwise, no ORDERED task attributes exist..
*/
return 1;
}
/*
* Called from fabric module context in transport_generic_new_cmd() and
* transport_generic_process_write()
*/
static int transport_execute_tasks(struct se_cmd *cmd)
{
int add_tasks;
struct se_device *se_dev = cmd->se_dev;
/*
* Call transport_cmd_check_stop() to see if a fabric exception
* has occurred that prevents execution.
*/
if (!transport_cmd_check_stop(cmd, 0, TRANSPORT_PROCESSING)) {
/*
* Check for SAM Task Attribute emulation and HEAD_OF_QUEUE
* attribute for the tasks of the received struct se_cmd CDB
*/
add_tasks = transport_execute_task_attr(cmd);
if (!add_tasks)
goto execute_tasks;
/*
* __transport_execute_tasks() -> __transport_add_tasks_from_cmd()
* adds associated se_tasks while holding dev->execute_task_lock
* before I/O dispath to avoid a double spinlock access.
*/
__transport_execute_tasks(se_dev, cmd);
return 0;
}
execute_tasks:
__transport_execute_tasks(se_dev, NULL);
return 0;
}
/*
* Called to check struct se_device tcq depth window, and once open pull struct se_task
* from struct se_device->execute_task_list and
*
* Called from transport_processing_thread()
*/
static int __transport_execute_tasks(struct se_device *dev, struct se_cmd *new_cmd)
{
int error;
struct se_cmd *cmd = NULL;
struct se_task *task = NULL;
unsigned long flags;
check_depth:
spin_lock_irq(&dev->execute_task_lock);
if (new_cmd != NULL)
__transport_add_tasks_from_cmd(new_cmd);
if (list_empty(&dev->execute_task_list)) {
spin_unlock_irq(&dev->execute_task_lock);
return 0;
}
task = list_first_entry(&dev->execute_task_list,
struct se_task, t_execute_list);
__transport_remove_task_from_execute_queue(task, dev);
spin_unlock_irq(&dev->execute_task_lock);
cmd = task->task_se_cmd;
spin_lock_irqsave(&cmd->t_state_lock, flags);
task->task_flags |= (TF_ACTIVE | TF_SENT);
atomic_inc(&cmd->t_task_cdbs_sent);
if (atomic_read(&cmd->t_task_cdbs_sent) ==
cmd->t_task_list_num)
atomic_set(&cmd->t_transport_sent, 1);
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
if (cmd->execute_task)
error = cmd->execute_task(task);
else
error = dev->transport->do_task(task);
if (error != 0) {
spin_lock_irqsave(&cmd->t_state_lock, flags);
task->task_flags &= ~TF_ACTIVE;
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
atomic_set(&cmd->t_transport_sent, 0);
transport_stop_tasks_for_cmd(cmd);
transport_generic_request_failure(cmd);
}
new_cmd = NULL;
goto check_depth;
return 0;
}
static inline u32 transport_get_sectors_6(
unsigned char *cdb,
struct se_cmd *cmd,
int *ret)
{
struct se_device *dev = cmd->se_dev;
/*
* Assume TYPE_DISK for non struct se_device objects.
* Use 8-bit sector value.
*/
if (!dev)
goto type_disk;
/*
* Use 24-bit allocation length for TYPE_TAPE.
*/
if (dev->transport->get_device_type(dev) == TYPE_TAPE)
return (u32)(cdb[2] << 16) + (cdb[3] << 8) + cdb[4];
/*
* Everything else assume TYPE_DISK Sector CDB location.
* Use 8-bit sector value. SBC-3 says:
*
* A TRANSFER LENGTH field set to zero specifies that 256
* logical blocks shall be written. Any other value
* specifies the number of logical blocks that shall be
* written.
*/
type_disk:
return cdb[4] ? : 256;
}
static inline u32 transport_get_sectors_10(
unsigned char *cdb,
struct se_cmd *cmd,
int *ret)
{
struct se_device *dev = cmd->se_dev;
/*
* Assume TYPE_DISK for non struct se_device objects.
* Use 16-bit sector value.
*/
if (!dev)
goto type_disk;
/*
* XXX_10 is not defined in SSC, throw an exception
*/
if (dev->transport->get_device_type(dev) == TYPE_TAPE) {
*ret = -EINVAL;
return 0;
}
/*
* Everything else assume TYPE_DISK Sector CDB location.
* Use 16-bit sector value.
*/
type_disk:
return (u32)(cdb[7] << 8) + cdb[8];
}
static inline u32 transport_get_sectors_12(
unsigned char *cdb,
struct se_cmd *cmd,
int *ret)
{
struct se_device *dev = cmd->se_dev;
/*
* Assume TYPE_DISK for non struct se_device objects.
* Use 32-bit sector value.
*/
if (!dev)
goto type_disk;
/*
* XXX_12 is not defined in SSC, throw an exception
*/
if (dev->transport->get_device_type(dev) == TYPE_TAPE) {
*ret = -EINVAL;
return 0;
}
/*
* Everything else assume TYPE_DISK Sector CDB location.
* Use 32-bit sector value.
*/
type_disk:
return (u32)(cdb[6] << 24) + (cdb[7] << 16) + (cdb[8] << 8) + cdb[9];
}
static inline u32 transport_get_sectors_16(
unsigned char *cdb,
struct se_cmd *cmd,
int *ret)
{
struct se_device *dev = cmd->se_dev;
/*
* Assume TYPE_DISK for non struct se_device objects.
* Use 32-bit sector value.
*/
if (!dev)
goto type_disk;
/*
* Use 24-bit allocation length for TYPE_TAPE.
*/
if (dev->transport->get_device_type(dev) == TYPE_TAPE)
return (u32)(cdb[12] << 16) + (cdb[13] << 8) + cdb[14];
type_disk:
return (u32)(cdb[10] << 24) + (cdb[11] << 16) +
(cdb[12] << 8) + cdb[13];
}
/*
* Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
*/
static inline u32 transport_get_sectors_32(
unsigned char *cdb,
struct se_cmd *cmd,
int *ret)
{
/*
* Assume TYPE_DISK for non struct se_device objects.
* Use 32-bit sector value.
*/
return (u32)(cdb[28] << 24) + (cdb[29] << 16) +
(cdb[30] << 8) + cdb[31];
}
static inline u32 transport_get_size(
u32 sectors,
unsigned char *cdb,
struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
if (dev->transport->get_device_type(dev) == TYPE_TAPE) {
if (cdb[1] & 1) { /* sectors */
return dev->se_sub_dev->se_dev_attrib.block_size * sectors;
} else /* bytes */
return sectors;
}
#if 0
pr_debug("Returning block_size: %u, sectors: %u == %u for"
" %s object\n", dev->se_sub_dev->se_dev_attrib.block_size, sectors,
dev->se_sub_dev->se_dev_attrib.block_size * sectors,
dev->transport->name);
#endif
return dev->se_sub_dev->se_dev_attrib.block_size * sectors;
}
static void transport_xor_callback(struct se_cmd *cmd)
{
unsigned char *buf, *addr;
struct scatterlist *sg;
unsigned int offset;
int i;
int count;
/*
* From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
*
* 1) read the specified logical block(s);
* 2) transfer logical blocks from the data-out buffer;
* 3) XOR the logical blocks transferred from the data-out buffer with
* the logical blocks read, storing the resulting XOR data in a buffer;
* 4) if the DISABLE WRITE bit is set to zero, then write the logical
* blocks transferred from the data-out buffer; and
* 5) transfer the resulting XOR data to the data-in buffer.
*/
buf = kmalloc(cmd->data_length, GFP_KERNEL);
if (!buf) {
pr_err("Unable to allocate xor_callback buf\n");
return;
}
/*
* Copy the scatterlist WRITE buffer located at cmd->t_data_sg
* into the locally allocated *buf
*/
sg_copy_to_buffer(cmd->t_data_sg,
cmd->t_data_nents,
buf,
cmd->data_length);
/*
* Now perform the XOR against the BIDI read memory located at
* cmd->t_mem_bidi_list
*/
offset = 0;
for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
addr = kmap_atomic(sg_page(sg), KM_USER0);
if (!addr)
goto out;
for (i = 0; i < sg->length; i++)
*(addr + sg->offset + i) ^= *(buf + offset + i);
offset += sg->length;
kunmap_atomic(addr, KM_USER0);
}
out:
kfree(buf);
}
/*
* Used to obtain Sense Data from underlying Linux/SCSI struct scsi_cmnd
*/
static int transport_get_sense_data(struct se_cmd *cmd)
{
unsigned char *buffer = cmd->sense_buffer, *sense_buffer = NULL;
struct se_device *dev = cmd->se_dev;
struct se_task *task = NULL, *task_tmp;
unsigned long flags;
u32 offset = 0;
WARN_ON(!cmd->se_lun);
if (!dev)
return 0;
spin_lock_irqsave(&cmd->t_state_lock, flags);
if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return 0;
}
list_for_each_entry_safe(task, task_tmp,
&cmd->t_task_list, t_list) {
if (!(task->task_flags & TF_HAS_SENSE))
continue;
if (!dev->transport->get_sense_buffer) {
pr_err("dev->transport->get_sense_buffer"
" is NULL\n");
continue;
}
sense_buffer = dev->transport->get_sense_buffer(task);
if (!sense_buffer) {
pr_err("ITT[0x%08x]_TASK[%p]: Unable to locate"
" sense buffer for task with sense\n",
cmd->se_tfo->get_task_tag(cmd), task);
continue;
}
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
offset = cmd->se_tfo->set_fabric_sense_len(cmd,
TRANSPORT_SENSE_BUFFER);
memcpy(&buffer[offset], sense_buffer,
TRANSPORT_SENSE_BUFFER);
cmd->scsi_status = task->task_scsi_status;
/* Automatically padded */
cmd->scsi_sense_length =
(TRANSPORT_SENSE_BUFFER + offset);
pr_debug("HBA_[%u]_PLUG[%s]: Set SAM STATUS: 0x%02x"
" and sense\n",
dev->se_hba->hba_id, dev->transport->name,
cmd->scsi_status);
return 0;
}
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return -1;
}
static inline long long transport_dev_end_lba(struct se_device *dev)
{
return dev->transport->get_blocks(dev) + 1;
}
static int transport_cmd_get_valid_sectors(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
u32 sectors;
if (dev->transport->get_device_type(dev) != TYPE_DISK)
return 0;
sectors = (cmd->data_length / dev->se_sub_dev->se_dev_attrib.block_size);
if ((cmd->t_task_lba + sectors) > transport_dev_end_lba(dev)) {
pr_err("LBA: %llu Sectors: %u exceeds"
" transport_dev_end_lba(): %llu\n",
cmd->t_task_lba, sectors,
transport_dev_end_lba(dev));
return -EINVAL;
}
return 0;
}
static int target_check_write_same_discard(unsigned char *flags, struct se_device *dev)
{
/*
* Determine if the received WRITE_SAME is used to for direct
* passthrough into Linux/SCSI with struct request via TCM/pSCSI
* or we are signaling the use of internal WRITE_SAME + UNMAP=1
* emulation for -> Linux/BLOCK disbard with TCM/IBLOCK code.
*/
int passthrough = (dev->transport->transport_type ==
TRANSPORT_PLUGIN_PHBA_PDEV);
if (!passthrough) {
if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
pr_err("WRITE_SAME PBDATA and LBDATA"
" bits not supported for Block Discard"
" Emulation\n");
return -ENOSYS;
}
/*
* Currently for the emulated case we only accept
* tpws with the UNMAP=1 bit set.
*/
if (!(flags[0] & 0x08)) {
pr_err("WRITE_SAME w/o UNMAP bit not"
" supported for Block Discard Emulation\n");
return -ENOSYS;
}
}
return 0;
}
/* transport_generic_cmd_sequencer():
*
* Generic Command Sequencer that should work for most DAS transport
* drivers.
*
* Called from transport_generic_allocate_tasks() in the $FABRIC_MOD
* RX Thread.
*
* FIXME: Need to support other SCSI OPCODES where as well.
*/
static int transport_generic_cmd_sequencer(
struct se_cmd *cmd,
unsigned char *cdb)
{
struct se_device *dev = cmd->se_dev;
struct se_subsystem_dev *su_dev = dev->se_sub_dev;
int ret = 0, sector_ret = 0, passthrough;
u32 sectors = 0, size = 0, pr_reg_type = 0;
u16 service_action;
u8 alua_ascq = 0;
/*
* Check for an existing UNIT ATTENTION condition
*/
if (core_scsi3_ua_check(cmd, cdb) < 0) {
cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
cmd->scsi_sense_reason = TCM_CHECK_CONDITION_UNIT_ATTENTION;
return -EINVAL;
}
/*
* Check status of Asymmetric Logical Unit Assignment port
*/
ret = su_dev->t10_alua.alua_state_check(cmd, cdb, &alua_ascq);
if (ret != 0) {
/*
* Set SCSI additional sense code (ASC) to 'LUN Not Accessible';
* The ALUA additional sense code qualifier (ASCQ) is determined
* by the ALUA primary or secondary access state..
*/
if (ret > 0) {
#if 0
pr_debug("[%s]: ALUA TG Port not available,"
" SenseKey: NOT_READY, ASC/ASCQ: 0x04/0x%02x\n",
cmd->se_tfo->get_fabric_name(), alua_ascq);
#endif
transport_set_sense_codes(cmd, 0x04, alua_ascq);
cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
cmd->scsi_sense_reason = TCM_CHECK_CONDITION_NOT_READY;
return -EINVAL;
}
goto out_invalid_cdb_field;
}
/*
* Check status for SPC-3 Persistent Reservations
*/
if (su_dev->t10_pr.pr_ops.t10_reservation_check(cmd, &pr_reg_type) != 0) {
if (su_dev->t10_pr.pr_ops.t10_seq_non_holder(
cmd, cdb, pr_reg_type) != 0) {
cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
cmd->se_cmd_flags |= SCF_SCSI_RESERVATION_CONFLICT;
cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
return -EBUSY;
}
/*
* This means the CDB is allowed for the SCSI Initiator port
* when said port is *NOT* holding the legacy SPC-2 or
* SPC-3 Persistent Reservation.
*/
}
/*
* If we operate in passthrough mode we skip most CDB emulation and
* instead hand the commands down to the physical SCSI device.
*/
passthrough =
(dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV);
switch (cdb[0]) {
case READ_6:
sectors = transport_get_sectors_6(cdb, cmd, §or_ret);
if (sector_ret)
goto out_unsupported_cdb;
size = transport_get_size(sectors, cdb, cmd);
cmd->t_task_lba = transport_lba_21(cdb);
cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
break;
case READ_10:
sectors = transport_get_sectors_10(cdb, cmd, §or_ret);
if (sector_ret)
goto out_unsupported_cdb;
size = transport_get_size(sectors, cdb, cmd);
cmd->t_task_lba = transport_lba_32(cdb);
cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
break;
case READ_12:
sectors = transport_get_sectors_12(cdb, cmd, §or_ret);
if (sector_ret)
goto out_unsupported_cdb;
size = transport_get_size(sectors, cdb, cmd);
cmd->t_task_lba = transport_lba_32(cdb);
cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
break;
case READ_16:
sectors = transport_get_sectors_16(cdb, cmd, §or_ret);
if (sector_ret)
goto out_unsupported_cdb;
size = transport_get_size(sectors, cdb, cmd);
cmd->t_task_lba = transport_lba_64(cdb);
cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
break;
case WRITE_6:
sectors = transport_get_sectors_6(cdb, cmd, §or_ret);
if (sector_ret)
goto out_unsupported_cdb;
size = transport_get_size(sectors, cdb, cmd);
cmd->t_task_lba = transport_lba_21(cdb);
cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
break;
case WRITE_10:
sectors = transport_get_sectors_10(cdb, cmd, §or_ret);
if (sector_ret)
goto out_unsupported_cdb;
size = transport_get_size(sectors, cdb, cmd);
cmd->t_task_lba = transport_lba_32(cdb);
if (cdb[1] & 0x8)
cmd->se_cmd_flags |= SCF_FUA;
cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
break;
case WRITE_12:
sectors = transport_get_sectors_12(cdb, cmd, §or_ret);
if (sector_ret)
goto out_unsupported_cdb;
size = transport_get_size(sectors, cdb, cmd);
cmd->t_task_lba = transport_lba_32(cdb);
if (cdb[1] & 0x8)
cmd->se_cmd_flags |= SCF_FUA;
cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
break;
case WRITE_16:
sectors = transport_get_sectors_16(cdb, cmd, §or_ret);
if (sector_ret)
goto out_unsupported_cdb;
size = transport_get_size(sectors, cdb, cmd);
cmd->t_task_lba = transport_lba_64(cdb);
if (cdb[1] & 0x8)
cmd->se_cmd_flags |= SCF_FUA;
cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
break;
case XDWRITEREAD_10:
if ((cmd->data_direction != DMA_TO_DEVICE) ||
!(cmd->se_cmd_flags & SCF_BIDI))
goto out_invalid_cdb_field;
sectors = transport_get_sectors_10(cdb, cmd, §or_ret);
if (sector_ret)
goto out_unsupported_cdb;
size = transport_get_size(sectors, cdb, cmd);
cmd->t_task_lba = transport_lba_32(cdb);
cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
/*
* Do now allow BIDI commands for passthrough mode.
*/
if (passthrough)
goto out_unsupported_cdb;
/*
* Setup BIDI XOR callback to be run after I/O completion.
*/
cmd->transport_complete_callback = &transport_xor_callback;
if (cdb[1] & 0x8)
cmd->se_cmd_flags |= SCF_FUA;
break;
case VARIABLE_LENGTH_CMD:
service_action = get_unaligned_be16(&cdb[8]);
switch (service_action) {
case XDWRITEREAD_32:
sectors = transport_get_sectors_32(cdb, cmd, §or_ret);
if (sector_ret)
goto out_unsupported_cdb;
size = transport_get_size(sectors, cdb, cmd);
/*
* Use WRITE_32 and READ_32 opcodes for the emulated
* XDWRITE_READ_32 logic.
*/
cmd->t_task_lba = transport_lba_64_ext(cdb);
cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
/*
* Do now allow BIDI commands for passthrough mode.
*/
if (passthrough)
goto out_unsupported_cdb;
/*
* Setup BIDI XOR callback to be run during after I/O
* completion.
*/
cmd->transport_complete_callback = &transport_xor_callback;
if (cdb[1] & 0x8)
cmd->se_cmd_flags |= SCF_FUA;
break;
case WRITE_SAME_32:
sectors = transport_get_sectors_32(cdb, cmd, §or_ret);
if (sector_ret)
goto out_unsupported_cdb;
if (sectors)
size = transport_get_size(1, cdb, cmd);
else {
pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
" supported\n");
goto out_invalid_cdb_field;
}
cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
if (target_check_write_same_discard(&cdb[10], dev) < 0)
goto out_unsupported_cdb;
if (!passthrough)
cmd->execute_task = target_emulate_write_same;
break;
default:
pr_err("VARIABLE_LENGTH_CMD service action"
" 0x%04x not supported\n", service_action);
goto out_unsupported_cdb;
}
break;
case MAINTENANCE_IN:
if (dev->transport->get_device_type(dev) != TYPE_ROM) {
/* MAINTENANCE_IN from SCC-2 */
/*
* Check for emulated MI_REPORT_TARGET_PGS.
*/
if (cdb[1] == MI_REPORT_TARGET_PGS &&
su_dev->t10_alua.alua_type == SPC3_ALUA_EMULATED) {
cmd->execute_task =
target_emulate_report_target_port_groups;
}
size = (cdb[6] << 24) | (cdb[7] << 16) |
(cdb[8] << 8) | cdb[9];
} else {
/* GPCMD_SEND_KEY from multi media commands */
size = (cdb[8] << 8) + cdb[9];
}
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case MODE_SELECT:
size = cdb[4];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case MODE_SELECT_10:
size = (cdb[7] << 8) + cdb[8];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case MODE_SENSE:
size = cdb[4];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
if (!passthrough)
cmd->execute_task = target_emulate_modesense;
break;
case MODE_SENSE_10:
size = (cdb[7] << 8) + cdb[8];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
if (!passthrough)
cmd->execute_task = target_emulate_modesense;
break;
case GPCMD_READ_BUFFER_CAPACITY:
case GPCMD_SEND_OPC:
case LOG_SELECT:
case LOG_SENSE:
size = (cdb[7] << 8) + cdb[8];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case READ_BLOCK_LIMITS:
size = READ_BLOCK_LEN;
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case GPCMD_GET_CONFIGURATION:
case GPCMD_READ_FORMAT_CAPACITIES:
case GPCMD_READ_DISC_INFO:
case GPCMD_READ_TRACK_RZONE_INFO:
size = (cdb[7] << 8) + cdb[8];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case PERSISTENT_RESERVE_IN:
if (su_dev->t10_pr.res_type == SPC3_PERSISTENT_RESERVATIONS)
cmd->execute_task = target_scsi3_emulate_pr_in;
size = (cdb[7] << 8) + cdb[8];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case PERSISTENT_RESERVE_OUT:
if (su_dev->t10_pr.res_type == SPC3_PERSISTENT_RESERVATIONS)
cmd->execute_task = target_scsi3_emulate_pr_out;
size = (cdb[7] << 8) + cdb[8];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case GPCMD_MECHANISM_STATUS:
case GPCMD_READ_DVD_STRUCTURE:
size = (cdb[8] << 8) + cdb[9];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case READ_POSITION:
size = READ_POSITION_LEN;
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case MAINTENANCE_OUT:
if (dev->transport->get_device_type(dev) != TYPE_ROM) {
/* MAINTENANCE_OUT from SCC-2
*
* Check for emulated MO_SET_TARGET_PGS.
*/
if (cdb[1] == MO_SET_TARGET_PGS &&
su_dev->t10_alua.alua_type == SPC3_ALUA_EMULATED) {
cmd->execute_task =
target_emulate_set_target_port_groups;
}
size = (cdb[6] << 24) | (cdb[7] << 16) |
(cdb[8] << 8) | cdb[9];
} else {
/* GPCMD_REPORT_KEY from multi media commands */
size = (cdb[8] << 8) + cdb[9];
}
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case INQUIRY:
size = (cdb[3] << 8) + cdb[4];
/*
* Do implict HEAD_OF_QUEUE processing for INQUIRY.
* See spc4r17 section 5.3
*/
if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
cmd->sam_task_attr = MSG_HEAD_TAG;
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
if (!passthrough)
cmd->execute_task = target_emulate_inquiry;
break;
case READ_BUFFER:
size = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case READ_CAPACITY:
size = READ_CAP_LEN;
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
if (!passthrough)
cmd->execute_task = target_emulate_readcapacity;
break;
case READ_MEDIA_SERIAL_NUMBER:
case SECURITY_PROTOCOL_IN:
case SECURITY_PROTOCOL_OUT:
size = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case SERVICE_ACTION_IN:
switch (cmd->t_task_cdb[1] & 0x1f) {
case SAI_READ_CAPACITY_16:
if (!passthrough)
cmd->execute_task =
target_emulate_readcapacity_16;
break;
default:
if (passthrough)
break;
pr_err("Unsupported SA: 0x%02x\n",
cmd->t_task_cdb[1] & 0x1f);
goto out_unsupported_cdb;
}
/*FALLTHROUGH*/
case ACCESS_CONTROL_IN:
case ACCESS_CONTROL_OUT:
case EXTENDED_COPY:
case READ_ATTRIBUTE:
case RECEIVE_COPY_RESULTS:
case WRITE_ATTRIBUTE:
size = (cdb[10] << 24) | (cdb[11] << 16) |
(cdb[12] << 8) | cdb[13];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case RECEIVE_DIAGNOSTIC:
case SEND_DIAGNOSTIC:
size = (cdb[3] << 8) | cdb[4];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
/* #warning FIXME: Figure out correct GPCMD_READ_CD blocksize. */
#if 0
case GPCMD_READ_CD:
sectors = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
size = (2336 * sectors);
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
#endif
case READ_TOC:
size = cdb[8];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case REQUEST_SENSE:
size = cdb[4];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
if (!passthrough)
cmd->execute_task = target_emulate_request_sense;
break;
case READ_ELEMENT_STATUS:
size = 65536 * cdb[7] + 256 * cdb[8] + cdb[9];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case WRITE_BUFFER:
size = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
case RESERVE:
case RESERVE_10:
/*
* The SPC-2 RESERVE does not contain a size in the SCSI CDB.
* Assume the passthrough or $FABRIC_MOD will tell us about it.
*/
if (cdb[0] == RESERVE_10)
size = (cdb[7] << 8) | cdb[8];
else
size = cmd->data_length;
/*
* Setup the legacy emulated handler for SPC-2 and
* >= SPC-3 compatible reservation handling (CRH=1)
* Otherwise, we assume the underlying SCSI logic is
* is running in SPC_PASSTHROUGH, and wants reservations
* emulation disabled.
*/
if (su_dev->t10_pr.res_type != SPC_PASSTHROUGH)
cmd->execute_task = target_scsi2_reservation_reserve;
cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
break;
case RELEASE:
case RELEASE_10:
/*
* The SPC-2 RELEASE does not contain a size in the SCSI CDB.
* Assume the passthrough or $FABRIC_MOD will tell us about it.
*/
if (cdb[0] == RELEASE_10)
size = (cdb[7] << 8) | cdb[8];
else
size = cmd->data_length;
if (su_dev->t10_pr.res_type != SPC_PASSTHROUGH)
cmd->execute_task = target_scsi2_reservation_release;
cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
break;
case SYNCHRONIZE_CACHE:
case 0x91: /* SYNCHRONIZE_CACHE_16: */
/*
* Extract LBA and range to be flushed for emulated SYNCHRONIZE_CACHE
*/
if (cdb[0] == SYNCHRONIZE_CACHE) {
sectors = transport_get_sectors_10(cdb, cmd, §or_ret);
cmd->t_task_lba = transport_lba_32(cdb);
} else {
sectors = transport_get_sectors_16(cdb, cmd, §or_ret);
cmd->t_task_lba = transport_lba_64(cdb);
}
if (sector_ret)
goto out_unsupported_cdb;
size = transport_get_size(sectors, cdb, cmd);
cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
if (passthrough)
break;
/*
* Check to ensure that LBA + Range does not exceed past end of
* device for IBLOCK and FILEIO ->do_sync_cache() backend calls
*/
if ((cmd->t_task_lba != 0) || (sectors != 0)) {
if (transport_cmd_get_valid_sectors(cmd) < 0)
goto out_invalid_cdb_field;
}
cmd->execute_task = target_emulate_synchronize_cache;
break;
case UNMAP:
size = get_unaligned_be16(&cdb[7]);
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
if (!passthrough)
cmd->execute_task = target_emulate_unmap;
break;
case WRITE_SAME_16:
sectors = transport_get_sectors_16(cdb, cmd, §or_ret);
if (sector_ret)
goto out_unsupported_cdb;
if (sectors)
size = transport_get_size(1, cdb, cmd);
else {
pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
goto out_invalid_cdb_field;
}
cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
if (target_check_write_same_discard(&cdb[1], dev) < 0)
goto out_unsupported_cdb;
if (!passthrough)
cmd->execute_task = target_emulate_write_same;
break;
case WRITE_SAME:
sectors = transport_get_sectors_10(cdb, cmd, §or_ret);
if (sector_ret)
goto out_unsupported_cdb;
if (sectors)
size = transport_get_size(1, cdb, cmd);
else {
pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
goto out_invalid_cdb_field;
}
cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
/*
* Follow sbcr26 with WRITE_SAME (10) and check for the existence
* of byte 1 bit 3 UNMAP instead of original reserved field
*/
if (target_check_write_same_discard(&cdb[1], dev) < 0)
goto out_unsupported_cdb;
if (!passthrough)
cmd->execute_task = target_emulate_write_same;
break;
case ALLOW_MEDIUM_REMOVAL:
case ERASE:
case REZERO_UNIT:
case SEEK_10:
case SPACE:
case START_STOP:
case TEST_UNIT_READY:
case VERIFY:
case WRITE_FILEMARKS:
cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
if (!passthrough)
cmd->execute_task = target_emulate_noop;
break;
case GPCMD_CLOSE_TRACK:
case INITIALIZE_ELEMENT_STATUS:
case GPCMD_LOAD_UNLOAD:
case GPCMD_SET_SPEED:
case MOVE_MEDIUM:
cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
break;
case REPORT_LUNS:
cmd->execute_task = target_report_luns;
size = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
/*
* Do implict HEAD_OF_QUEUE processing for REPORT_LUNS
* See spc4r17 section 5.3
*/
if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
cmd->sam_task_attr = MSG_HEAD_TAG;
cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
break;
default:
pr_warn("TARGET_CORE[%s]: Unsupported SCSI Opcode"
" 0x%02x, sending CHECK_CONDITION.\n",
cmd->se_tfo->get_fabric_name(), cdb[0]);
goto out_unsupported_cdb;
}
if (size != cmd->data_length) {
pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
" %u does not match SCSI CDB Length: %u for SAM Opcode:"
" 0x%02x\n", cmd->se_tfo->get_fabric_name(),
cmd->data_length, size, cdb[0]);
cmd->cmd_spdtl = size;
if (cmd->data_direction == DMA_TO_DEVICE) {
pr_err("Rejecting underflow/overflow"
" WRITE data\n");
goto out_invalid_cdb_field;
}
/*
* Reject READ_* or WRITE_* with overflow/underflow for
* type SCF_SCSI_DATA_SG_IO_CDB.
*/
if (!ret && (dev->se_sub_dev->se_dev_attrib.block_size != 512)) {
pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
" CDB on non 512-byte sector setup subsystem"
" plugin: %s\n", dev->transport->name);
/* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
goto out_invalid_cdb_field;
}
if (size > cmd->data_length) {
cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
cmd->residual_count = (size - cmd->data_length);
} else {
cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
cmd->residual_count = (cmd->data_length - size);
}
cmd->data_length = size;
}
/* reject any command that we don't have a handler for */
if (!(passthrough || cmd->execute_task ||
(cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB)))
goto out_unsupported_cdb;
transport_set_supported_SAM_opcode(cmd);
return ret;
out_unsupported_cdb:
cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
return -EINVAL;
out_invalid_cdb_field:
cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
return -EINVAL;
}
/*
* Called from I/O completion to determine which dormant/delayed
* and ordered cmds need to have their tasks added to the execution queue.
*/
static void transport_complete_task_attr(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
struct se_cmd *cmd_p, *cmd_tmp;
int new_active_tasks = 0;
if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
atomic_dec(&dev->simple_cmds);
smp_mb__after_atomic_dec();
dev->dev_cur_ordered_id++;
pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
" SIMPLE: %u\n", dev->dev_cur_ordered_id,
cmd->se_ordered_id);
} else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
dev->dev_cur_ordered_id++;
pr_debug("Incremented dev_cur_ordered_id: %u for"
" HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
cmd->se_ordered_id);
} else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
atomic_dec(&dev->dev_ordered_sync);
smp_mb__after_atomic_dec();
dev->dev_cur_ordered_id++;
pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
" %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
}
/*
* Process all commands up to the last received
* ORDERED task attribute which requires another blocking
* boundary
*/
spin_lock(&dev->delayed_cmd_lock);
list_for_each_entry_safe(cmd_p, cmd_tmp,
&dev->delayed_cmd_list, se_delayed_node) {
list_del(&cmd_p->se_delayed_node);
spin_unlock(&dev->delayed_cmd_lock);
pr_debug("Calling add_tasks() for"
" cmd_p: 0x%02x Task Attr: 0x%02x"
" Dormant -> Active, se_ordered_id: %u\n",
cmd_p->t_task_cdb[0],
cmd_p->sam_task_attr, cmd_p->se_ordered_id);
transport_add_tasks_from_cmd(cmd_p);
new_active_tasks++;
spin_lock(&dev->delayed_cmd_lock);
if (cmd_p->sam_task_attr == MSG_ORDERED_TAG)
break;
}
spin_unlock(&dev->delayed_cmd_lock);
/*
* If new tasks have become active, wake up the transport thread
* to do the processing of the Active tasks.
*/
if (new_active_tasks != 0)
wake_up_interruptible(&dev->dev_queue_obj.thread_wq);
}
static void transport_complete_qf(struct se_cmd *cmd)
{
int ret = 0;
if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
transport_complete_task_attr(cmd);
if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
ret = cmd->se_tfo->queue_status(cmd);
if (ret)
goto out;
}
switch (cmd->data_direction) {
case DMA_FROM_DEVICE:
ret = cmd->se_tfo->queue_data_in(cmd);
break;
case DMA_TO_DEVICE:
if (cmd->t_bidi_data_sg) {
ret = cmd->se_tfo->queue_data_in(cmd);
if (ret < 0)
break;
}
/* Fall through for DMA_TO_DEVICE */
case DMA_NONE:
ret = cmd->se_tfo->queue_status(cmd);
break;
default:
break;
}
out:
if (ret < 0) {
transport_handle_queue_full(cmd, cmd->se_dev);
return;
}
transport_lun_remove_cmd(cmd);
transport_cmd_check_stop_to_fabric(cmd);
}
static void transport_handle_queue_full(
struct se_cmd *cmd,
struct se_device *dev)
{
spin_lock_irq(&dev->qf_cmd_lock);
list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
atomic_inc(&dev->dev_qf_count);
smp_mb__after_atomic_inc();
spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
schedule_work(&cmd->se_dev->qf_work_queue);
}
static void target_complete_ok_work(struct work_struct *work)
{
struct se_cmd *cmd = container_of(work, struct se_cmd, work);
int reason = 0, ret;
/*
* Check if we need to move delayed/dormant tasks from cmds on the
* delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
* Attribute.
*/
if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
transport_complete_task_attr(cmd);
/*
* Check to schedule QUEUE_FULL work, or execute an existing
* cmd->transport_qf_callback()
*/
if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
schedule_work(&cmd->se_dev->qf_work_queue);
/*
* Check if we need to retrieve a sense buffer from
* the struct se_cmd in question.
*/
if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
if (transport_get_sense_data(cmd) < 0)
reason = TCM_NON_EXISTENT_LUN;
/*
* Only set when an struct se_task->task_scsi_status returned
* a non GOOD status.
*/
if (cmd->scsi_status) {
ret = transport_send_check_condition_and_sense(
cmd, reason, 1);
if (ret == -EAGAIN || ret == -ENOMEM)
goto queue_full;
transport_lun_remove_cmd(cmd);
transport_cmd_check_stop_to_fabric(cmd);
return;
}
}
/*
* Check for a callback, used by amongst other things
* XDWRITE_READ_10 emulation.
*/
if (cmd->transport_complete_callback)
cmd->transport_complete_callback(cmd);
switch (cmd->data_direction) {
case DMA_FROM_DEVICE:
spin_lock(&cmd->se_lun->lun_sep_lock);
if (cmd->se_lun->lun_sep) {
cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
cmd->data_length;
}
spin_unlock(&cmd->se_lun->lun_sep_lock);
ret = cmd->se_tfo->queue_data_in(cmd);
if (ret == -EAGAIN || ret == -ENOMEM)
goto queue_full;
break;
case DMA_TO_DEVICE:
spin_lock(&cmd->se_lun->lun_sep_lock);
if (cmd->se_lun->lun_sep) {
cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
cmd->data_length;
}
spin_unlock(&cmd->se_lun->lun_sep_lock);
/*
* Check if we need to send READ payload for BIDI-COMMAND
*/
if (cmd->t_bidi_data_sg) {
spin_lock(&cmd->se_lun->lun_sep_lock);
if (cmd->se_lun->lun_sep) {
cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
cmd->data_length;
}
spin_unlock(&cmd->se_lun->lun_sep_lock);
ret = cmd->se_tfo->queue_data_in(cmd);
if (ret == -EAGAIN || ret == -ENOMEM)
goto queue_full;
break;
}
/* Fall through for DMA_TO_DEVICE */
case DMA_NONE:
ret = cmd->se_tfo->queue_status(cmd);
if (ret == -EAGAIN || ret == -ENOMEM)
goto queue_full;
break;
default:
break;
}
transport_lun_remove_cmd(cmd);
transport_cmd_check_stop_to_fabric(cmd);
return;
queue_full:
pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
" data_direction: %d\n", cmd, cmd->data_direction);
cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
transport_handle_queue_full(cmd, cmd->se_dev);
}
static void transport_free_dev_tasks(struct se_cmd *cmd)
{
struct se_task *task, *task_tmp;
unsigned long flags;
LIST_HEAD(dispose_list);
spin_lock_irqsave(&cmd->t_state_lock, flags);
list_for_each_entry_safe(task, task_tmp,
&cmd->t_task_list, t_list) {
if (!(task->task_flags & TF_ACTIVE))
list_move_tail(&task->t_list, &dispose_list);
}
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
while (!list_empty(&dispose_list)) {
task = list_first_entry(&dispose_list, struct se_task, t_list);
if (task->task_sg != cmd->t_data_sg &&
task->task_sg != cmd->t_bidi_data_sg)
kfree(task->task_sg);
list_del(&task->t_list);
cmd->se_dev->transport->free_task(task);
}
}
static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
{
struct scatterlist *sg;
int count;
for_each_sg(sgl, sg, nents, count)
__free_page(sg_page(sg));
kfree(sgl);
}
static inline void transport_free_pages(struct se_cmd *cmd)
{
if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC)
return;
transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
cmd->t_data_sg = NULL;
cmd->t_data_nents = 0;
transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
cmd->t_bidi_data_sg = NULL;
cmd->t_bidi_data_nents = 0;
}
/**
* transport_release_cmd - free a command
* @cmd: command to free
*
* This routine unconditionally frees a command, and reference counting
* or list removal must be done in the caller.
*/
static void transport_release_cmd(struct se_cmd *cmd)
{
BUG_ON(!cmd->se_tfo);
if (cmd->se_tmr_req)
core_tmr_release_req(cmd->se_tmr_req);
if (cmd->t_task_cdb != cmd->__t_task_cdb)
kfree(cmd->t_task_cdb);
/*
* If this cmd has been setup with target_get_sess_cmd(), drop
* the kref and call ->release_cmd() in kref callback.
*/
if (cmd->check_release != 0) {
target_put_sess_cmd(cmd->se_sess, cmd);
return;
}
cmd->se_tfo->release_cmd(cmd);
}
/**
* transport_put_cmd - release a reference to a command
* @cmd: command to release
*
* This routine releases our reference to the command and frees it if possible.
*/
static void transport_put_cmd(struct se_cmd *cmd)
{
unsigned long flags;
int free_tasks = 0;
spin_lock_irqsave(&cmd->t_state_lock, flags);
if (atomic_read(&cmd->t_fe_count)) {
if (!atomic_dec_and_test(&cmd->t_fe_count))
goto out_busy;
}
if (atomic_read(&cmd->t_se_count)) {
if (!atomic_dec_and_test(&cmd->t_se_count))
goto out_busy;
}
if (atomic_read(&cmd->transport_dev_active)) {
atomic_set(&cmd->transport_dev_active, 0);
transport_all_task_dev_remove_state(cmd);
free_tasks = 1;
}
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
if (free_tasks != 0)
transport_free_dev_tasks(cmd);
transport_free_pages(cmd);
transport_release_cmd(cmd);
return;
out_busy:
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
}
/*
* transport_generic_map_mem_to_cmd - Use fabric-alloced pages instead of
* allocating in the core.
* @cmd: Associated se_cmd descriptor
* @mem: SGL style memory for TCM WRITE / READ
* @sg_mem_num: Number of SGL elements
* @mem_bidi_in: SGL style memory for TCM BIDI READ
* @sg_mem_bidi_num: Number of BIDI READ SGL elements
*
* Return: nonzero return cmd was rejected for -ENOMEM or inproper usage
* of parameters.
*/
int transport_generic_map_mem_to_cmd(
struct se_cmd *cmd,
struct scatterlist *sgl,
u32 sgl_count,
struct scatterlist *sgl_bidi,
u32 sgl_bidi_count)
{
if (!sgl || !sgl_count)
return 0;
if ((cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) ||
(cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB)) {
/*
* Reject SCSI data overflow with map_mem_to_cmd() as incoming
* scatterlists already have been set to follow what the fabric
* passes for the original expected data transfer length.
*/
if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
pr_warn("Rejecting SCSI DATA overflow for fabric using"
" SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
return -EINVAL;
}
cmd->t_data_sg = sgl;
cmd->t_data_nents = sgl_count;
if (sgl_bidi && sgl_bidi_count) {
cmd->t_bidi_data_sg = sgl_bidi;
cmd->t_bidi_data_nents = sgl_bidi_count;
}
cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
}
return 0;
}
EXPORT_SYMBOL(transport_generic_map_mem_to_cmd);
void *transport_kmap_data_sg(struct se_cmd *cmd)
{
struct scatterlist *sg = cmd->t_data_sg;
struct page **pages;
int i;
BUG_ON(!sg);
/*
* We need to take into account a possible offset here for fabrics like
* tcm_loop who may be using a contig buffer from the SCSI midlayer for
* control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
*/
if (!cmd->t_data_nents)
return NULL;
else if (cmd->t_data_nents == 1)
return kmap(sg_page(sg)) + sg->offset;
/* >1 page. use vmap */
pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
if (!pages)
return NULL;
/* convert sg[] to pages[] */
for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
pages[i] = sg_page(sg);
}
cmd->t_data_vmap = vmap(pages, cmd->t_data_nents, VM_MAP, PAGE_KERNEL);
kfree(pages);
if (!cmd->t_data_vmap)
return NULL;
return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
}
EXPORT_SYMBOL(transport_kmap_data_sg);
void transport_kunmap_data_sg(struct se_cmd *cmd)
{
if (!cmd->t_data_nents)
return;
else if (cmd->t_data_nents == 1)
kunmap(sg_page(cmd->t_data_sg));
vunmap(cmd->t_data_vmap);
cmd->t_data_vmap = NULL;
}
EXPORT_SYMBOL(transport_kunmap_data_sg);
static int
transport_generic_get_mem(struct se_cmd *cmd)
{
u32 length = cmd->data_length;
unsigned int nents;
struct page *page;
gfp_t zero_flag;
int i = 0;
nents = DIV_ROUND_UP(length, PAGE_SIZE);
cmd->t_data_sg = kmalloc(sizeof(struct scatterlist) * nents, GFP_KERNEL);
if (!cmd->t_data_sg)
return -ENOMEM;
cmd->t_data_nents = nents;
sg_init_table(cmd->t_data_sg, nents);
zero_flag = cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB ? 0 : __GFP_ZERO;
while (length) {
u32 page_len = min_t(u32, length, PAGE_SIZE);
page = alloc_page(GFP_KERNEL | zero_flag);
if (!page)
goto out;
sg_set_page(&cmd->t_data_sg[i], page, page_len, 0);
length -= page_len;
i++;
}
return 0;
out:
while (i >= 0) {
__free_page(sg_page(&cmd->t_data_sg[i]));
i--;
}
kfree(cmd->t_data_sg);
cmd->t_data_sg = NULL;
return -ENOMEM;
}
/* Reduce sectors if they are too long for the device */
static inline sector_t transport_limit_task_sectors(
struct se_device *dev,
unsigned long long lba,
sector_t sectors)
{
sectors = min_t(sector_t, sectors, dev->se_sub_dev->se_dev_attrib.max_sectors);
if (dev->transport->get_device_type(dev) == TYPE_DISK)
if ((lba + sectors) > transport_dev_end_lba(dev))
sectors = ((transport_dev_end_lba(dev) - lba) + 1);
return sectors;
}
/*
* This function can be used by HW target mode drivers to create a linked
* scatterlist from all contiguously allocated struct se_task->task_sg[].
* This is intended to be called during the completion path by TCM Core
* when struct target_core_fabric_ops->check_task_sg_chaining is enabled.
*/
void transport_do_task_sg_chain(struct se_cmd *cmd)
{
struct scatterlist *sg_first = NULL;
struct scatterlist *sg_prev = NULL;
int sg_prev_nents = 0;
struct scatterlist *sg;
struct se_task *task;
u32 chained_nents = 0;
int i;
BUG_ON(!cmd->se_tfo->task_sg_chaining);
/*
* Walk the struct se_task list and setup scatterlist chains
* for each contiguously allocated struct se_task->task_sg[].
*/
list_for_each_entry(task, &cmd->t_task_list, t_list) {
if (!task->task_sg)
continue;
if (!sg_first) {
sg_first = task->task_sg;
chained_nents = task->task_sg_nents;
} else {
sg_chain(sg_prev, sg_prev_nents, task->task_sg);
chained_nents += task->task_sg_nents;
}
/*
* For the padded tasks, use the extra SGL vector allocated
* in transport_allocate_data_tasks() for the sg_prev_nents
* offset into sg_chain() above.
*
* We do not need the padding for the last task (or a single
* task), but in that case we will never use the sg_prev_nents
* value below which would be incorrect.
*/
sg_prev_nents = (task->task_sg_nents + 1);
sg_prev = task->task_sg;
}
/*
* Setup the starting pointer and total t_tasks_sg_linked_no including
* padding SGs for linking and to mark the end.
*/
cmd->t_tasks_sg_chained = sg_first;
cmd->t_tasks_sg_chained_no = chained_nents;
pr_debug("Setup cmd: %p cmd->t_tasks_sg_chained: %p and"
" t_tasks_sg_chained_no: %u\n", cmd, cmd->t_tasks_sg_chained,
cmd->t_tasks_sg_chained_no);
for_each_sg(cmd->t_tasks_sg_chained, sg,
cmd->t_tasks_sg_chained_no, i) {
pr_debug("SG[%d]: %p page: %p length: %d offset: %d\n",
i, sg, sg_page(sg), sg->length, sg->offset);
if (sg_is_chain(sg))
pr_debug("SG: %p sg_is_chain=1\n", sg);
if (sg_is_last(sg))
pr_debug("SG: %p sg_is_last=1\n", sg);
}
}
EXPORT_SYMBOL(transport_do_task_sg_chain);
/*
* Break up cmd into chunks transport can handle
*/
static int
transport_allocate_data_tasks(struct se_cmd *cmd,
enum dma_data_direction data_direction,
struct scatterlist *cmd_sg, unsigned int sgl_nents)
{
struct se_device *dev = cmd->se_dev;
int task_count, i;
unsigned long long lba;
sector_t sectors, dev_max_sectors;
u32 sector_size;
if (transport_cmd_get_valid_sectors(cmd) < 0)
return -EINVAL;
dev_max_sectors = dev->se_sub_dev->se_dev_attrib.max_sectors;
sector_size = dev->se_sub_dev->se_dev_attrib.block_size;
WARN_ON(cmd->data_length % sector_size);
lba = cmd->t_task_lba;
sectors = DIV_ROUND_UP(cmd->data_length, sector_size);
task_count = DIV_ROUND_UP_SECTOR_T(sectors, dev_max_sectors);
/*
* If we need just a single task reuse the SG list in the command
* and avoid a lot of work.
*/
if (task_count == 1) {
struct se_task *task;
unsigned long flags;
task = transport_generic_get_task(cmd, data_direction);
if (!task)
return -ENOMEM;
task->task_sg = cmd_sg;
task->task_sg_nents = sgl_nents;
task->task_lba = lba;
task->task_sectors = sectors;
task->task_size = task->task_sectors * sector_size;
spin_lock_irqsave(&cmd->t_state_lock, flags);
list_add_tail(&task->t_list, &cmd->t_task_list);
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return task_count;
}
for (i = 0; i < task_count; i++) {
struct se_task *task;
unsigned int task_size, task_sg_nents_padded;
struct scatterlist *sg;
unsigned long flags;
int count;
task = transport_generic_get_task(cmd, data_direction);
if (!task)
return -ENOMEM;
task->task_lba = lba;
task->task_sectors = min(sectors, dev_max_sectors);
task->task_size = task->task_sectors * sector_size;
/*
* This now assumes that passed sg_ents are in PAGE_SIZE chunks
* in order to calculate the number per task SGL entries
*/
task->task_sg_nents = DIV_ROUND_UP(task->task_size, PAGE_SIZE);
/*
* Check if the fabric module driver is requesting that all
* struct se_task->task_sg[] be chained together.. If so,
* then allocate an extra padding SG entry for linking and
* marking the end of the chained SGL for every task except
* the last one for (task_count > 1) operation, or skipping
* the extra padding for the (task_count == 1) case.
*/
if (cmd->se_tfo->task_sg_chaining && (i < (task_count - 1))) {
task_sg_nents_padded = (task->task_sg_nents + 1);
} else
task_sg_nents_padded = task->task_sg_nents;
task->task_sg = kmalloc(sizeof(struct scatterlist) *
task_sg_nents_padded, GFP_KERNEL);
if (!task->task_sg) {
cmd->se_dev->transport->free_task(task);
return -ENOMEM;
}
sg_init_table(task->task_sg, task_sg_nents_padded);
task_size = task->task_size;
/* Build new sgl, only up to task_size */
for_each_sg(task->task_sg, sg, task->task_sg_nents, count) {
if (cmd_sg->length > task_size)
break;
*sg = *cmd_sg;
task_size -= cmd_sg->length;
cmd_sg = sg_next(cmd_sg);
}
lba += task->task_sectors;
sectors -= task->task_sectors;
spin_lock_irqsave(&cmd->t_state_lock, flags);
list_add_tail(&task->t_list, &cmd->t_task_list);
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
}
return task_count;
}
static int
transport_allocate_control_task(struct se_cmd *cmd)
{
struct se_task *task;
unsigned long flags;
/* Workaround for handling zero-length control CDBs */
if ((cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB) &&
!cmd->data_length)
return 0;
task = transport_generic_get_task(cmd, cmd->data_direction);
if (!task)
return -ENOMEM;
task->task_sg = cmd->t_data_sg;
task->task_size = cmd->data_length;
task->task_sg_nents = cmd->t_data_nents;
spin_lock_irqsave(&cmd->t_state_lock, flags);
list_add_tail(&task->t_list, &cmd->t_task_list);
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
/* Success! Return number of tasks allocated */
return 1;
}
/*
* Allocate any required ressources to execute the command, and either place
* it on the execution queue if possible. For writes we might not have the
* payload yet, thus notify the fabric via a call to ->write_pending instead.
*/
int transport_generic_new_cmd(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
int task_cdbs, task_cdbs_bidi = 0;
int set_counts = 1;
int ret = 0;
/*
* Determine is the TCM fabric module has already allocated physical
* memory, and is directly calling transport_generic_map_mem_to_cmd()
* beforehand.
*/
if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
cmd->data_length) {
ret = transport_generic_get_mem(cmd);
if (ret < 0)
goto out_fail;
}
/*
* For BIDI command set up the read tasks first.
*/
if (cmd->t_bidi_data_sg &&
dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV) {
BUG_ON(!(cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB));
task_cdbs_bidi = transport_allocate_data_tasks(cmd,
DMA_FROM_DEVICE, cmd->t_bidi_data_sg,
cmd->t_bidi_data_nents);
if (task_cdbs_bidi <= 0)
goto out_fail;
atomic_inc(&cmd->t_fe_count);
atomic_inc(&cmd->t_se_count);
set_counts = 0;
}
if (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) {
task_cdbs = transport_allocate_data_tasks(cmd,
cmd->data_direction, cmd->t_data_sg,
cmd->t_data_nents);
} else {
task_cdbs = transport_allocate_control_task(cmd);
}
if (task_cdbs < 0)
goto out_fail;
else if (!task_cdbs && (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB)) {
cmd->t_state = TRANSPORT_COMPLETE;
atomic_set(&cmd->t_transport_active, 1);
if (cmd->t_task_cdb[0] == REQUEST_SENSE) {
u8 ua_asc = 0, ua_ascq = 0;
core_scsi3_ua_clear_for_request_sense(cmd,
&ua_asc, &ua_ascq);
}
INIT_WORK(&cmd->work, target_complete_ok_work);
queue_work(target_completion_wq, &cmd->work);
return 0;
}
if (set_counts) {
atomic_inc(&cmd->t_fe_count);
atomic_inc(&cmd->t_se_count);
}
cmd->t_task_list_num = (task_cdbs + task_cdbs_bidi);
atomic_set(&cmd->t_task_cdbs_left, cmd->t_task_list_num);
atomic_set(&cmd->t_task_cdbs_ex_left, cmd->t_task_list_num);
/*
* For WRITEs, let the fabric know its buffer is ready..
* This WRITE struct se_cmd (and all of its associated struct se_task's)
* will be added to the struct se_device execution queue after its WRITE
* data has arrived. (ie: It gets handled by the transport processing
* thread a second time)
*/
if (cmd->data_direction == DMA_TO_DEVICE) {
transport_add_tasks_to_state_queue(cmd);
return transport_generic_write_pending(cmd);
}
/*
* Everything else but a WRITE, add the struct se_cmd's struct se_task's
* to the execution queue.
*/
transport_execute_tasks(cmd);
return 0;
out_fail:
cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
return -EINVAL;
}
EXPORT_SYMBOL(transport_generic_new_cmd);
/* transport_generic_process_write():
*
*
*/
void transport_generic_process_write(struct se_cmd *cmd)
{
transport_execute_tasks(cmd);
}
EXPORT_SYMBOL(transport_generic_process_write);
static void transport_write_pending_qf(struct se_cmd *cmd)
{
int ret;
ret = cmd->se_tfo->write_pending(cmd);
if (ret == -EAGAIN || ret == -ENOMEM) {
pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
cmd);
transport_handle_queue_full(cmd, cmd->se_dev);
}
}
static int transport_generic_write_pending(struct se_cmd *cmd)
{
unsigned long flags;
int ret;
spin_lock_irqsave(&cmd->t_state_lock, flags);
cmd->t_state = TRANSPORT_WRITE_PENDING;
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
/*
* Clear the se_cmd for WRITE_PENDING status in order to set
* cmd->t_transport_active=0 so that transport_generic_handle_data
* can be called from HW target mode interrupt code. This is safe
* to be called with transport_off=1 before the cmd->se_tfo->write_pending
* because the se_cmd->se_lun pointer is not being cleared.
*/
transport_cmd_check_stop(cmd, 1, 0);
/*
* Call the fabric write_pending function here to let the
* frontend know that WRITE buffers are ready.
*/
ret = cmd->se_tfo->write_pending(cmd);
if (ret == -EAGAIN || ret == -ENOMEM)
goto queue_full;
else if (ret < 0)
return ret;
return 1;
queue_full:
pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
transport_handle_queue_full(cmd, cmd->se_dev);
return 0;
}
void transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
{
if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
if (wait_for_tasks && cmd->se_tmr_req)
transport_wait_for_tasks(cmd);
transport_release_cmd(cmd);
} else {
if (wait_for_tasks)
transport_wait_for_tasks(cmd);
core_dec_lacl_count(cmd->se_sess->se_node_acl, cmd);
if (cmd->se_lun)
transport_lun_remove_cmd(cmd);
transport_free_dev_tasks(cmd);
transport_put_cmd(cmd);
}
}
EXPORT_SYMBOL(transport_generic_free_cmd);
/* target_get_sess_cmd - Add command to active ->sess_cmd_list
* @se_sess: session to reference
* @se_cmd: command descriptor to add
* @ack_kref: Signal that fabric will perform an ack target_put_sess_cmd()
*/
void target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd,
bool ack_kref)
{
unsigned long flags;
kref_init(&se_cmd->cmd_kref);
/*
* Add a second kref if the fabric caller is expecting to handle
* fabric acknowledgement that requires two target_put_sess_cmd()
* invocations before se_cmd descriptor release.
*/
if (ack_kref == true)
kref_get(&se_cmd->cmd_kref);
spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
se_cmd->check_release = 1;
spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
}
EXPORT_SYMBOL(target_get_sess_cmd);
static void target_release_cmd_kref(struct kref *kref)
{
struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
struct se_session *se_sess = se_cmd->se_sess;
unsigned long flags;
spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
if (list_empty(&se_cmd->se_cmd_list)) {
spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
WARN_ON(1);
return;
}
if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
complete(&se_cmd->cmd_wait_comp);
return;
}
list_del(&se_cmd->se_cmd_list);
spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
se_cmd->se_tfo->release_cmd(se_cmd);
}
/* target_put_sess_cmd - Check for active I/O shutdown via kref_put
* @se_sess: session to reference
* @se_cmd: command descriptor to drop
*/
int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
{
return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
}
EXPORT_SYMBOL(target_put_sess_cmd);
/* target_splice_sess_cmd_list - Split active cmds into sess_wait_list
* @se_sess: session to split
*/
void target_splice_sess_cmd_list(struct se_session *se_sess)
{
struct se_cmd *se_cmd;
unsigned long flags;
WARN_ON(!list_empty(&se_sess->sess_wait_list));
INIT_LIST_HEAD(&se_sess->sess_wait_list);
spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
se_sess->sess_tearing_down = 1;
list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
se_cmd->cmd_wait_set = 1;
spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
}
EXPORT_SYMBOL(target_splice_sess_cmd_list);
/* target_wait_for_sess_cmds - Wait for outstanding descriptors
* @se_sess: session to wait for active I/O
* @wait_for_tasks: Make extra transport_wait_for_tasks call
*/
void target_wait_for_sess_cmds(
struct se_session *se_sess,
int wait_for_tasks)
{
struct se_cmd *se_cmd, *tmp_cmd;
bool rc = false;
list_for_each_entry_safe(se_cmd, tmp_cmd,
&se_sess->sess_wait_list, se_cmd_list) {
list_del(&se_cmd->se_cmd_list);
pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
" %d\n", se_cmd, se_cmd->t_state,
se_cmd->se_tfo->get_cmd_state(se_cmd));
if (wait_for_tasks) {
pr_debug("Calling transport_wait_for_tasks se_cmd: %p t_state: %d,"
" fabric state: %d\n", se_cmd, se_cmd->t_state,
se_cmd->se_tfo->get_cmd_state(se_cmd));
rc = transport_wait_for_tasks(se_cmd);
pr_debug("After transport_wait_for_tasks se_cmd: %p t_state: %d,"
" fabric state: %d\n", se_cmd, se_cmd->t_state,
se_cmd->se_tfo->get_cmd_state(se_cmd));
}
if (!rc) {
wait_for_completion(&se_cmd->cmd_wait_comp);
pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
" fabric state: %d\n", se_cmd, se_cmd->t_state,
se_cmd->se_tfo->get_cmd_state(se_cmd));
}
se_cmd->se_tfo->release_cmd(se_cmd);
}
}
EXPORT_SYMBOL(target_wait_for_sess_cmds);
/* transport_lun_wait_for_tasks():
*
* Called from ConfigFS context to stop the passed struct se_cmd to allow
* an struct se_lun to be successfully shutdown.
*/
static int transport_lun_wait_for_tasks(struct se_cmd *cmd, struct se_lun *lun)
{
unsigned long flags;
int ret;
/*
* If the frontend has already requested this struct se_cmd to
* be stopped, we can safely ignore this struct se_cmd.
*/
spin_lock_irqsave(&cmd->t_state_lock, flags);
if (atomic_read(&cmd->t_transport_stop)) {
atomic_set(&cmd->transport_lun_stop, 0);
pr_debug("ConfigFS ITT[0x%08x] - t_transport_stop =="
" TRUE, skipping\n", cmd->se_tfo->get_task_tag(cmd));
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
transport_cmd_check_stop(cmd, 1, 0);
return -EPERM;
}
atomic_set(&cmd->transport_lun_fe_stop, 1);
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
wake_up_interruptible(&cmd->se_dev->dev_queue_obj.thread_wq);
ret = transport_stop_tasks_for_cmd(cmd);
pr_debug("ConfigFS: cmd: %p t_tasks: %d stop tasks ret:"
" %d\n", cmd, cmd->t_task_list_num, ret);
if (!ret) {
pr_debug("ConfigFS: ITT[0x%08x] - stopping cmd....\n",
cmd->se_tfo->get_task_tag(cmd));
wait_for_completion(&cmd->transport_lun_stop_comp);
pr_debug("ConfigFS: ITT[0x%08x] - stopped cmd....\n",
cmd->se_tfo->get_task_tag(cmd));
}
transport_remove_cmd_from_queue(cmd);
return 0;
}
static void __transport_clear_lun_from_sessions(struct se_lun *lun)
{
struct se_cmd *cmd = NULL;
unsigned long lun_flags, cmd_flags;
/*
* Do exception processing and return CHECK_CONDITION status to the
* Initiator Port.
*/
spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
while (!list_empty(&lun->lun_cmd_list)) {
cmd = list_first_entry(&lun->lun_cmd_list,
struct se_cmd, se_lun_node);
list_del(&cmd->se_lun_node);
atomic_set(&cmd->transport_lun_active, 0);
/*
* This will notify iscsi_target_transport.c:
* transport_cmd_check_stop() that a LUN shutdown is in
* progress for the iscsi_cmd_t.
*/
spin_lock(&cmd->t_state_lock);
pr_debug("SE_LUN[%d] - Setting cmd->transport"
"_lun_stop for ITT: 0x%08x\n",
cmd->se_lun->unpacked_lun,
cmd->se_tfo->get_task_tag(cmd));
atomic_set(&cmd->transport_lun_stop, 1);
spin_unlock(&cmd->t_state_lock);
spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
if (!cmd->se_lun) {
pr_err("ITT: 0x%08x, [i,t]_state: %u/%u\n",
cmd->se_tfo->get_task_tag(cmd),
cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
BUG();
}
/*
* If the Storage engine still owns the iscsi_cmd_t, determine
* and/or stop its context.
*/
pr_debug("SE_LUN[%d] - ITT: 0x%08x before transport"
"_lun_wait_for_tasks()\n", cmd->se_lun->unpacked_lun,
cmd->se_tfo->get_task_tag(cmd));
if (transport_lun_wait_for_tasks(cmd, cmd->se_lun) < 0) {
spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
continue;
}
pr_debug("SE_LUN[%d] - ITT: 0x%08x after transport_lun"
"_wait_for_tasks(): SUCCESS\n",
cmd->se_lun->unpacked_lun,
cmd->se_tfo->get_task_tag(cmd));
spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
if (!atomic_read(&cmd->transport_dev_active)) {
spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
goto check_cond;
}
atomic_set(&cmd->transport_dev_active, 0);
transport_all_task_dev_remove_state(cmd);
spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
transport_free_dev_tasks(cmd);
/*
* The Storage engine stopped this struct se_cmd before it was
* send to the fabric frontend for delivery back to the
* Initiator Node. Return this SCSI CDB back with an
* CHECK_CONDITION status.
*/
check_cond:
transport_send_check_condition_and_sense(cmd,
TCM_NON_EXISTENT_LUN, 0);
/*
* If the fabric frontend is waiting for this iscsi_cmd_t to
* be released, notify the waiting thread now that LU has
* finished accessing it.
*/
spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
if (atomic_read(&cmd->transport_lun_fe_stop)) {
pr_debug("SE_LUN[%d] - Detected FE stop for"
" struct se_cmd: %p ITT: 0x%08x\n",
lun->unpacked_lun,
cmd, cmd->se_tfo->get_task_tag(cmd));
spin_unlock_irqrestore(&cmd->t_state_lock,
cmd_flags);
transport_cmd_check_stop(cmd, 1, 0);
complete(&cmd->transport_lun_fe_stop_comp);
spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
continue;
}
pr_debug("SE_LUN[%d] - ITT: 0x%08x finished processing\n",
lun->unpacked_lun, cmd->se_tfo->get_task_tag(cmd));
spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
}
spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
}
static int transport_clear_lun_thread(void *p)
{
struct se_lun *lun = p;
__transport_clear_lun_from_sessions(lun);
complete(&lun->lun_shutdown_comp);
return 0;
}
int transport_clear_lun_from_sessions(struct se_lun *lun)
{
struct task_struct *kt;
kt = kthread_run(transport_clear_lun_thread, lun,
"tcm_cl_%u", lun->unpacked_lun);
if (IS_ERR(kt)) {
pr_err("Unable to start clear_lun thread\n");
return PTR_ERR(kt);
}
wait_for_completion(&lun->lun_shutdown_comp);
return 0;
}
/**
* transport_wait_for_tasks - wait for completion to occur
* @cmd: command to wait
*
* Called from frontend fabric context to wait for storage engine
* to pause and/or release frontend generated struct se_cmd.
*/
bool transport_wait_for_tasks(struct se_cmd *cmd)
{
unsigned long flags;
spin_lock_irqsave(&cmd->t_state_lock, flags);
if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) && !(cmd->se_tmr_req)) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return false;
}
/*
* Only perform a possible wait_for_tasks if SCF_SUPPORTED_SAM_OPCODE
* has been set in transport_set_supported_SAM_opcode().
*/
if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) && !cmd->se_tmr_req) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return false;
}
/*
* If we are already stopped due to an external event (ie: LUN shutdown)
* sleep until the connection can have the passed struct se_cmd back.
* The cmd->transport_lun_stopped_sem will be upped by
* transport_clear_lun_from_sessions() once the ConfigFS context caller
* has completed its operation on the struct se_cmd.
*/
if (atomic_read(&cmd->transport_lun_stop)) {
pr_debug("wait_for_tasks: Stopping"
" wait_for_completion(&cmd->t_tasktransport_lun_fe"
"_stop_comp); for ITT: 0x%08x\n",
cmd->se_tfo->get_task_tag(cmd));
/*
* There is a special case for WRITES where a FE exception +
* LUN shutdown means ConfigFS context is still sleeping on
* transport_lun_stop_comp in transport_lun_wait_for_tasks().
* We go ahead and up transport_lun_stop_comp just to be sure
* here.
*/
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
complete(&cmd->transport_lun_stop_comp);
wait_for_completion(&cmd->transport_lun_fe_stop_comp);
spin_lock_irqsave(&cmd->t_state_lock, flags);
transport_all_task_dev_remove_state(cmd);
/*
* At this point, the frontend who was the originator of this
* struct se_cmd, now owns the structure and can be released through
* normal means below.
*/
pr_debug("wait_for_tasks: Stopped"
" wait_for_completion(&cmd->t_tasktransport_lun_fe_"
"stop_comp); for ITT: 0x%08x\n",
cmd->se_tfo->get_task_tag(cmd));
atomic_set(&cmd->transport_lun_stop, 0);
}
if (!atomic_read(&cmd->t_transport_active) ||
atomic_read(&cmd->t_transport_aborted)) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return false;
}
atomic_set(&cmd->t_transport_stop, 1);
pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
" i_state: %d, t_state: %d, t_transport_stop = TRUE\n",
cmd, cmd->se_tfo->get_task_tag(cmd),
cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
wake_up_interruptible(&cmd->se_dev->dev_queue_obj.thread_wq);
wait_for_completion(&cmd->t_transport_stop_comp);
spin_lock_irqsave(&cmd->t_state_lock, flags);
atomic_set(&cmd->t_transport_active, 0);
atomic_set(&cmd->t_transport_stop, 0);
pr_debug("wait_for_tasks: Stopped wait_for_compltion("
"&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
cmd->se_tfo->get_task_tag(cmd));
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return true;
}
EXPORT_SYMBOL(transport_wait_for_tasks);
static int transport_get_sense_codes(
struct se_cmd *cmd,
u8 *asc,
u8 *ascq)
{
*asc = cmd->scsi_asc;
*ascq = cmd->scsi_ascq;
return 0;
}
static int transport_set_sense_codes(
struct se_cmd *cmd,
u8 asc,
u8 ascq)
{
cmd->scsi_asc = asc;
cmd->scsi_ascq = ascq;
return 0;
}
int transport_send_check_condition_and_sense(
struct se_cmd *cmd,
u8 reason,
int from_transport)
{
unsigned char *buffer = cmd->sense_buffer;
unsigned long flags;
int offset;
u8 asc = 0, ascq = 0;
spin_lock_irqsave(&cmd->t_state_lock, flags);
if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return 0;
}
cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
if (!reason && from_transport)
goto after_reason;
if (!from_transport)
cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
/*
* Data Segment and SenseLength of the fabric response PDU.
*
* TRANSPORT_SENSE_BUFFER is now set to SCSI_SENSE_BUFFERSIZE
* from include/scsi/scsi_cmnd.h
*/
offset = cmd->se_tfo->set_fabric_sense_len(cmd,
TRANSPORT_SENSE_BUFFER);
/*
* Actual SENSE DATA, see SPC-3 7.23.2 SPC_SENSE_KEY_OFFSET uses
* SENSE KEY values from include/scsi/scsi.h
*/
switch (reason) {
case TCM_NON_EXISTENT_LUN:
/* CURRENT ERROR */
buffer[offset] = 0x70;
buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* LOGICAL UNIT NOT SUPPORTED */
buffer[offset+SPC_ASC_KEY_OFFSET] = 0x25;
break;
case TCM_UNSUPPORTED_SCSI_OPCODE:
case TCM_SECTOR_COUNT_TOO_MANY:
/* CURRENT ERROR */
buffer[offset] = 0x70;
buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* INVALID COMMAND OPERATION CODE */
buffer[offset+SPC_ASC_KEY_OFFSET] = 0x20;
break;
case TCM_UNKNOWN_MODE_PAGE:
/* CURRENT ERROR */
buffer[offset] = 0x70;
buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* INVALID FIELD IN CDB */
buffer[offset+SPC_ASC_KEY_OFFSET] = 0x24;
break;
case TCM_CHECK_CONDITION_ABORT_CMD:
/* CURRENT ERROR */
buffer[offset] = 0x70;
buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ABORTED COMMAND */
buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
/* BUS DEVICE RESET FUNCTION OCCURRED */
buffer[offset+SPC_ASC_KEY_OFFSET] = 0x29;
buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x03;
break;
case TCM_INCORRECT_AMOUNT_OF_DATA:
/* CURRENT ERROR */
buffer[offset] = 0x70;
buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ABORTED COMMAND */
buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
/* WRITE ERROR */
buffer[offset+SPC_ASC_KEY_OFFSET] = 0x0c;
/* NOT ENOUGH UNSOLICITED DATA */
buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x0d;
break;
case TCM_INVALID_CDB_FIELD:
/* CURRENT ERROR */
buffer[offset] = 0x70;
buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* INVALID FIELD IN CDB */
buffer[offset+SPC_ASC_KEY_OFFSET] = 0x24;
break;
case TCM_INVALID_PARAMETER_LIST:
/* CURRENT ERROR */
buffer[offset] = 0x70;
buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* INVALID FIELD IN PARAMETER LIST */
buffer[offset+SPC_ASC_KEY_OFFSET] = 0x26;
break;
case TCM_UNEXPECTED_UNSOLICITED_DATA:
/* CURRENT ERROR */
buffer[offset] = 0x70;
buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ABORTED COMMAND */
buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
/* WRITE ERROR */
buffer[offset+SPC_ASC_KEY_OFFSET] = 0x0c;
/* UNEXPECTED_UNSOLICITED_DATA */
buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x0c;
break;
case TCM_SERVICE_CRC_ERROR:
/* CURRENT ERROR */
buffer[offset] = 0x70;
buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ABORTED COMMAND */
buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
/* PROTOCOL SERVICE CRC ERROR */
buffer[offset+SPC_ASC_KEY_OFFSET] = 0x47;
/* N/A */
buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x05;
break;
case TCM_SNACK_REJECTED:
/* CURRENT ERROR */
buffer[offset] = 0x70;
buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ABORTED COMMAND */
buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
/* READ ERROR */
buffer[offset+SPC_ASC_KEY_OFFSET] = 0x11;
/* FAILED RETRANSMISSION REQUEST */
buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x13;
break;
case TCM_WRITE_PROTECTED:
/* CURRENT ERROR */
buffer[offset] = 0x70;
buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* DATA PROTECT */
buffer[offset+SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
/* WRITE PROTECTED */
buffer[offset+SPC_ASC_KEY_OFFSET] = 0x27;
break;
case TCM_CHECK_CONDITION_UNIT_ATTENTION:
/* CURRENT ERROR */
buffer[offset] = 0x70;
buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* UNIT ATTENTION */
buffer[offset+SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
buffer[offset+SPC_ASC_KEY_OFFSET] = asc;
buffer[offset+SPC_ASCQ_KEY_OFFSET] = ascq;
break;
case TCM_CHECK_CONDITION_NOT_READY:
/* CURRENT ERROR */
buffer[offset] = 0x70;
buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* Not Ready */
buffer[offset+SPC_SENSE_KEY_OFFSET] = NOT_READY;
transport_get_sense_codes(cmd, &asc, &ascq);
buffer[offset+SPC_ASC_KEY_OFFSET] = asc;
buffer[offset+SPC_ASCQ_KEY_OFFSET] = ascq;
break;
case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
default:
/* CURRENT ERROR */
buffer[offset] = 0x70;
buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* LOGICAL UNIT COMMUNICATION FAILURE */
buffer[offset+SPC_ASC_KEY_OFFSET] = 0x80;
break;
}
/*
* This code uses linux/include/scsi/scsi.h SAM status codes!
*/
cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
/*
* Automatically padded, this value is encoded in the fabric's
* data_length response PDU containing the SCSI defined sense data.
*/
cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER + offset;
after_reason:
return cmd->se_tfo->queue_status(cmd);
}
EXPORT_SYMBOL(transport_send_check_condition_and_sense);
int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
{
int ret = 0;
if (atomic_read(&cmd->t_transport_aborted) != 0) {
if (!send_status ||
(cmd->se_cmd_flags & SCF_SENT_DELAYED_TAS))
return 1;
#if 0
pr_debug("Sending delayed SAM_STAT_TASK_ABORTED"
" status for CDB: 0x%02x ITT: 0x%08x\n",
cmd->t_task_cdb[0],
cmd->se_tfo->get_task_tag(cmd));
#endif
cmd->se_cmd_flags |= SCF_SENT_DELAYED_TAS;
cmd->se_tfo->queue_status(cmd);
ret = 1;
}
return ret;
}
EXPORT_SYMBOL(transport_check_aborted_status);
void transport_send_task_abort(struct se_cmd *cmd)
{
unsigned long flags;
spin_lock_irqsave(&cmd->t_state_lock, flags);
if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return;
}
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
/*
* If there are still expected incoming fabric WRITEs, we wait
* until until they have completed before sending a TASK_ABORTED
* response. This response with TASK_ABORTED status will be
* queued back to fabric module by transport_check_aborted_status().
*/
if (cmd->data_direction == DMA_TO_DEVICE) {
if (cmd->se_tfo->write_pending_status(cmd) != 0) {
atomic_inc(&cmd->t_transport_aborted);
smp_mb__after_atomic_inc();
}
}
cmd->scsi_status = SAM_STAT_TASK_ABORTED;
#if 0
pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
" ITT: 0x%08x\n", cmd->t_task_cdb[0],
cmd->se_tfo->get_task_tag(cmd));
#endif
cmd->se_tfo->queue_status(cmd);
}
static int transport_generic_do_tmr(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
struct se_tmr_req *tmr = cmd->se_tmr_req;
int ret;
switch (tmr->function) {
case TMR_ABORT_TASK:
tmr->response = TMR_FUNCTION_REJECTED;
break;
case TMR_ABORT_TASK_SET:
case TMR_CLEAR_ACA:
case TMR_CLEAR_TASK_SET:
tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
break;
case TMR_LUN_RESET:
ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
TMR_FUNCTION_REJECTED;
break;
case TMR_TARGET_WARM_RESET:
tmr->response = TMR_FUNCTION_REJECTED;
break;
case TMR_TARGET_COLD_RESET:
tmr->response = TMR_FUNCTION_REJECTED;
break;
default:
pr_err("Uknown TMR function: 0x%02x.\n",
tmr->function);
tmr->response = TMR_FUNCTION_REJECTED;
break;
}
cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
cmd->se_tfo->queue_tm_rsp(cmd);
transport_cmd_check_stop_to_fabric(cmd);
return 0;
}
/* transport_processing_thread():
*
*
*/
static int transport_processing_thread(void *param)
{
int ret;
struct se_cmd *cmd;
struct se_device *dev = param;
while (!kthread_should_stop()) {
ret = wait_event_interruptible(dev->dev_queue_obj.thread_wq,
atomic_read(&dev->dev_queue_obj.queue_cnt) ||
kthread_should_stop());
if (ret < 0)
goto out;
get_cmd:
cmd = transport_get_cmd_from_queue(&dev->dev_queue_obj);
if (!cmd)
continue;
switch (cmd->t_state) {
case TRANSPORT_NEW_CMD:
BUG();
break;
case TRANSPORT_NEW_CMD_MAP:
if (!cmd->se_tfo->new_cmd_map) {
pr_err("cmd->se_tfo->new_cmd_map is"
" NULL for TRANSPORT_NEW_CMD_MAP\n");
BUG();
}
ret = cmd->se_tfo->new_cmd_map(cmd);
if (ret < 0) {
transport_generic_request_failure(cmd);
break;
}
ret = transport_generic_new_cmd(cmd);
if (ret < 0) {
transport_generic_request_failure(cmd);
break;
}
break;
case TRANSPORT_PROCESS_WRITE:
transport_generic_process_write(cmd);
break;
case TRANSPORT_PROCESS_TMR:
transport_generic_do_tmr(cmd);
break;
case TRANSPORT_COMPLETE_QF_WP:
transport_write_pending_qf(cmd);
break;
case TRANSPORT_COMPLETE_QF_OK:
transport_complete_qf(cmd);
break;
default:
pr_err("Unknown t_state: %d for ITT: 0x%08x "
"i_state: %d on SE LUN: %u\n",
cmd->t_state,
cmd->se_tfo->get_task_tag(cmd),
cmd->se_tfo->get_cmd_state(cmd),
cmd->se_lun->unpacked_lun);
BUG();
}
goto get_cmd;
}
out:
WARN_ON(!list_empty(&dev->state_task_list));
WARN_ON(!list_empty(&dev->dev_queue_obj.qobj_list));
dev->process_thread = NULL;
return 0;
}