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linux/drivers/target/target_core_transport.c
Andy Grover 7c9e7a6fe1 target: Add a user-passthrough backstore 
Add a LIO storage engine that presents commands to userspace for execution.
This would allow more complex backstores to be implemented out-of-kernel,
and also make experimentation a-la FUSE (but at the SCSI level -- "SUSE"?)
possible.

It uses a mmap()able UIO device per LUN to share a command ring and data
area. The commands are raw SCSI CDBs and iovs for in/out data. The command
ring is also reused for returning scsi command status and optional sense
data.

This implementation is based on Shaohua Li's earlier version but heavily
modified. Differences include:

* Shared memory allocated by kernel, not locked-down user pages
* Single ring for command request and response
* Offsets instead of embedded pointers
* Generic SCSI CDB passthrough instead of per-cmd specialization in ring
  format.
* Uses UIO device instead of anon_file passed in mailbox.
* Optional in-kernel handling of some commands.

The main reason for these differences is to permit greater resiliency
if the user process dies or hangs.

Things not yet implemented (on purpose):

* Zero copy. The data area is flexible enough to allow page flipping or
  backend-allocated pages to be used by fabrics, but it's not clear these
  are performance wins. Can come later.
* Out-of-order command completion by userspace. Possible to add by just
  allowing userspace to change cmd_id in rsp cmd entries, but currently
  not supported.
* No locks between kernel cmd submission and completion routines. Sounds
  like it's possible, but this can come later.
* Sparse allocation of mmaped area. Current code vmallocs the whole thing.
  If the mapped area was larger and not fully mapped then the driver would
  have more freedom to change cmd and data area sizes based on demand.

Current code open issues:

* The use of idrs may be overkill -- we maybe can replace them with a
  simple counter to generate cmd_ids, and a hash table to get a cmd_id's
  associated pointer.
* Use of a free-running counter for cmd ring instead of explicit modulo
  math. This would require power-of-2 cmd ring size.

(Add kconfig depends NET - Randy)

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2014-10-03 11:15:20 -07:00

2964 lines
79 KiB
C
Raw Blame History

/*******************************************************************************
* Filename: target_core_transport.c
*
* This file contains the Generic Target Engine Core.
*
* (c) Copyright 2002-2013 Datera, Inc.
*
* Nicholas A. Bellinger <nab@kernel.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
******************************************************************************/
#include <linux/net.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/kthread.h>
#include <linux/in.h>
#include <linux/cdrom.h>
#include <linux/module.h>
#include <linux/ratelimit.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"
#define CREATE_TRACE_POINTS
#include <trace/events/target.h>
static struct workqueue_struct *target_completion_wq;
static struct kmem_cache *se_sess_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;
struct kmem_cache *t10_alua_lba_map_cache;
struct kmem_cache *t10_alua_lba_map_mem_cache;
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 int transport_put_cmd(struct se_cmd *cmd);
static void target_complete_ok_work(struct work_struct *work);
int init_se_kmem_caches(void)
{
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;
}
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;
}
t10_alua_lba_map_cache = kmem_cache_create(
"t10_alua_lba_map_cache",
sizeof(struct t10_alua_lba_map),
__alignof__(struct t10_alua_lba_map), 0, NULL);
if (!t10_alua_lba_map_cache) {
pr_err("kmem_cache_create() for t10_alua_lba_map_"
"cache failed\n");
goto out_free_tg_pt_gp_mem_cache;
}
t10_alua_lba_map_mem_cache = kmem_cache_create(
"t10_alua_lba_map_mem_cache",
sizeof(struct t10_alua_lba_map_member),
__alignof__(struct t10_alua_lba_map_member), 0, NULL);
if (!t10_alua_lba_map_mem_cache) {
pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
"cache failed\n");
goto out_free_lba_map_cache;
}
target_completion_wq = alloc_workqueue("target_completion",
WQ_MEM_RECLAIM, 0);
if (!target_completion_wq)
goto out_free_lba_map_mem_cache;
return 0;
out_free_lba_map_mem_cache:
kmem_cache_destroy(t10_alua_lba_map_mem_cache);
out_free_lba_map_cache:
kmem_cache_destroy(t10_alua_lba_map_cache);
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:
return -ENOMEM;
}
void release_se_kmem_caches(void)
{
destroy_workqueue(target_completion_wq);
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);
kmem_cache_destroy(t10_alua_lba_map_cache);
kmem_cache_destroy(t10_alua_lba_map_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;
}
void transport_subsystem_check_init(void)
{
int ret;
static int sub_api_initialized;
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_user");
if (ret != 0)
pr_err("Unable to load target_core_user\n");
sub_api_initialized = 1;
}
struct se_session *transport_init_session(enum target_prot_op sup_prot_ops)
{
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);
kref_init(&se_sess->sess_kref);
se_sess->sup_prot_ops = sup_prot_ops;
return se_sess;
}
EXPORT_SYMBOL(transport_init_session);
int transport_alloc_session_tags(struct se_session *se_sess,
unsigned int tag_num, unsigned int tag_size)
{
int rc;
se_sess->sess_cmd_map = kzalloc(tag_num * tag_size,
GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
if (!se_sess->sess_cmd_map) {
se_sess->sess_cmd_map = vzalloc(tag_num * tag_size);
if (!se_sess->sess_cmd_map) {
pr_err("Unable to allocate se_sess->sess_cmd_map\n");
return -ENOMEM;
}
}
rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
if (rc < 0) {
pr_err("Unable to init se_sess->sess_tag_pool,"
" tag_num: %u\n", tag_num);
if (is_vmalloc_addr(se_sess->sess_cmd_map))
vfree(se_sess->sess_cmd_map);
else
kfree(se_sess->sess_cmd_map);
se_sess->sess_cmd_map = NULL;
return -ENOMEM;
}
return 0;
}
EXPORT_SYMBOL(transport_alloc_session_tags);
struct se_session *transport_init_session_tags(unsigned int tag_num,
unsigned int tag_size,
enum target_prot_op sup_prot_ops)
{
struct se_session *se_sess;
int rc;
se_sess = transport_init_session(sup_prot_ops);
if (IS_ERR(se_sess))
return se_sess;
rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
if (rc < 0) {
transport_free_session(se_sess);
return ERR_PTR(-ENOMEM);
}
return se_sess;
}
EXPORT_SYMBOL(transport_init_session_tags);
/*
* Called with spin_lock_irqsave(&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]);
}
kref_get(&se_nacl->acl_kref);
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)
{
unsigned long flags;
spin_lock_irqsave(&se_tpg->session_lock, flags);
__transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
spin_unlock_irqrestore(&se_tpg->session_lock, flags);
}
EXPORT_SYMBOL(transport_register_session);
static void target_release_session(struct kref *kref)
{
struct se_session *se_sess = container_of(kref,
struct se_session, sess_kref);
struct se_portal_group *se_tpg = se_sess->se_tpg;
se_tpg->se_tpg_tfo->close_session(se_sess);
}
void target_get_session(struct se_session *se_sess)
{
kref_get(&se_sess->sess_kref);
}
EXPORT_SYMBOL(target_get_session);
void target_put_session(struct se_session *se_sess)
{
struct se_portal_group *tpg = se_sess->se_tpg;
if (tpg->se_tpg_tfo->put_session != NULL) {
tpg->se_tpg_tfo->put_session(se_sess);
return;
}
kref_put(&se_sess->sess_kref, target_release_session);
}
EXPORT_SYMBOL(target_put_session);
static void target_complete_nacl(struct kref *kref)
{
struct se_node_acl *nacl = container_of(kref,
struct se_node_acl, acl_kref);
complete(&nacl->acl_free_comp);
}
void target_put_nacl(struct se_node_acl *nacl)
{
kref_put(&nacl->acl_kref, target_complete_nacl);
}
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);
if (se_nacl->acl_stop == 0)
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)
{
if (se_sess->sess_cmd_map) {
percpu_ida_destroy(&se_sess->sess_tag_pool);
if (is_vmalloc_addr(se_sess->sess_cmd_map))
vfree(se_sess->sess_cmd_map);
else
kfree(se_sess->sess_cmd_map);
}
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 target_core_fabric_ops *se_tfo;
struct se_node_acl *se_nacl;
unsigned long flags;
bool comp_nacl = true;
if (!se_tpg) {
transport_free_session(se_sess);
return;
}
se_tfo = se_tpg->se_tpg_tfo;
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;
spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
if (se_nacl && se_nacl->dynamic_node_acl) {
if (!se_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_tfo->tpg_release_fabric_acl(se_tpg, se_nacl);
comp_nacl = false;
spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
}
}
spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
se_tpg->se_tpg_tfo->get_fabric_name());
/*
* If last kref is dropping now for an explicit NodeACL, awake sleeping
* ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
* removal context.
*/
if (se_nacl && comp_nacl)
target_put_nacl(se_nacl);
transport_free_session(se_sess);
}
EXPORT_SYMBOL(transport_deregister_session);
/*
* Called with cmd->t_state_lock held.
*/
static void target_remove_from_state_list(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
unsigned long flags;
if (!dev)
return;
if (cmd->transport_state & CMD_T_BUSY)
return;
spin_lock_irqsave(&dev->execute_task_lock, flags);
if (cmd->state_active) {
list_del(&cmd->state_list);
cmd->state_active = false;
}
spin_unlock_irqrestore(&dev->execute_task_lock, flags);
}
static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists,
bool write_pending)
{
unsigned long flags;
spin_lock_irqsave(&cmd->t_state_lock, flags);
if (write_pending)
cmd->t_state = TRANSPORT_WRITE_PENDING;
if (remove_from_lists) {
target_remove_from_state_list(cmd);
/*
* Clear struct se_cmd->se_lun before the handoff to FE.
*/
cmd->se_lun = NULL;
}
/*
* Determine if frontend context caller is requesting the stopping of
* this command for frontend exceptions.
*/
if (cmd->transport_state & CMD_T_STOP) {
pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
__func__, __LINE__,
cmd->se_tfo->get_task_tag(cmd));
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
complete_all(&cmd->t_transport_stop_comp);
return 1;
}
cmd->transport_state &= ~CMD_T_ACTIVE;
if (remove_from_lists) {
/*
* 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;
}
static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
{
return transport_cmd_check_stop(cmd, true, false);
}
static void transport_lun_remove_cmd(struct se_cmd *cmd)
{
struct se_lun *lun = cmd->se_lun;
if (!lun)
return;
if (cmpxchg(&cmd->lun_ref_active, true, false))
percpu_ref_put(&lun->lun_ref);
}
void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
{
if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
transport_lun_remove_cmd(cmd);
/*
* Allow the fabric driver to unmap any resources before
* releasing the descriptor via TFO->release_cmd()
*/
if (remove)
cmd->se_tfo->aborted_task(cmd);
if (transport_cmd_check_stop_to_fabric(cmd))
return;
if (remove)
transport_put_cmd(cmd);
}
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,
TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
}
/*
* Used when asking transport to copy Sense Data from the underlying
* Linux/SCSI struct scsi_cmnd
*/
static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
WARN_ON(!cmd->se_lun);
if (!dev)
return NULL;
if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
return NULL;
cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
return cmd->sense_buffer;
}
void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
{
struct se_device *dev = cmd->se_dev;
int success = scsi_status == GOOD;
unsigned long flags;
cmd->scsi_status = scsi_status;
spin_lock_irqsave(&cmd->t_state_lock, flags);
cmd->transport_state &= ~CMD_T_BUSY;
if (dev && dev->transport->transport_complete) {
dev->transport->transport_complete(cmd,
cmd->t_data_sg,
transport_get_sense_buffer(cmd));
if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
success = 1;
}
/*
* See if we are waiting to complete for an exception condition.
*/
if (cmd->transport_state & CMD_T_REQUEST_STOP) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
complete(&cmd->task_stop_comp);
return;
}
/*
* Check for case where an explicit ABORT_TASK has been received
* and transport_wait_for_tasks() will be waiting for completion..
*/
if (cmd->transport_state & CMD_T_ABORTED &&
cmd->transport_state & CMD_T_STOP) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
complete_all(&cmd->t_transport_stop_comp);
return;
} else if (!success) {
INIT_WORK(&cmd->work, target_complete_failure_work);
} else {
INIT_WORK(&cmd->work, target_complete_ok_work);
}
cmd->t_state = TRANSPORT_COMPLETE;
cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
queue_work(target_completion_wq, &cmd->work);
}
EXPORT_SYMBOL(target_complete_cmd);
void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
{
if (scsi_status == SAM_STAT_GOOD && length < cmd->data_length) {
if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
cmd->residual_count += cmd->data_length - length;
} else {
cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
cmd->residual_count = cmd->data_length - length;
}
cmd->data_length = length;
}
target_complete_cmd(cmd, scsi_status);
}
EXPORT_SYMBOL(target_complete_cmd_with_length);
static void target_add_to_state_list(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
unsigned long flags;
spin_lock_irqsave(&dev->execute_task_lock, flags);
if (!cmd->state_active) {
list_add_tail(&cmd->state_list, &dev->state_list);
cmd->state_active = true;
}
spin_unlock_irqrestore(&dev->execute_task_lock, flags);
}
/*
* Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
*/
static void transport_write_pending_qf(struct se_cmd *cmd);
static void transport_complete_qf(struct se_cmd *cmd);
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_mb(&dev->dev_qf_count);
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");
if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
transport_write_pending_qf(cmd);
else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
transport_complete_qf(cmd);
}
}
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: ");
if (dev->export_count)
*bl += sprintf(b + *bl, "ACTIVATED");
else
*bl += sprintf(b + *bl, "DEACTIVATED");
*bl += sprintf(b + *bl, " Max Queue Depth: %d", dev->queue_depth);
*bl += sprintf(b + *bl, " SectorSize: %u HwMaxSectors: %u\n",
dev->dev_attrib.block_size,
dev->dev_attrib.hw_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 */
snprintf(buf, sizeof(buf),
"T10 VPD Binary Device Identifier: %s\n",
&vpd->device_identifier[0]);
break;
case 0x02: /* ASCII */
snprintf(buf, sizeof(buf),
"T10 VPD ASCII Device Identifier: %s\n",
&vpd->device_identifier[0]);
break;
case 0x03: /* UTF-8 */
snprintf(buf, sizeof(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 identifier */
/*
* 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);
sense_reason_t
target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
{
struct se_device *dev = cmd->se_dev;
if (cmd->unknown_data_length) {
cmd->data_length = size;
} else 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, cmd->t_task_cdb[0]);
if (cmd->data_direction == DMA_TO_DEVICE) {
pr_err("Rejecting underflow/overflow"
" WRITE data\n");
return TCM_INVALID_CDB_FIELD;
}
/*
* Reject READ_* or WRITE_* with overflow/underflow for
* type SCF_SCSI_DATA_CDB.
*/
if (dev->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 */
return TCM_INVALID_CDB_FIELD;
}
/*
* For the overflow case keep the existing fabric provided
* ->data_length. Otherwise for the underflow case, reset
* ->data_length to the smaller SCSI expected data transfer
* length.
*/
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;
}
}
return 0;
}
/*
* 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_delayed_node);
INIT_LIST_HEAD(&cmd->se_qf_node);
INIT_LIST_HEAD(&cmd->se_cmd_list);
INIT_LIST_HEAD(&cmd->state_list);
init_completion(&cmd->t_transport_stop_comp);
init_completion(&cmd->cmd_wait_comp);
init_completion(&cmd->task_stop_comp);
spin_lock_init(&cmd->t_state_lock);
kref_init(&cmd->cmd_kref);
cmd->transport_state = CMD_T_DEV_ACTIVE;
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;
cmd->state_active = false;
}
EXPORT_SYMBOL(transport_init_se_cmd);
static sense_reason_t
transport_check_alloc_task_attr(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
/*
* Check if SAM Task Attribute emulation is enabled for this
* struct se_device storage object
*/
if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
return 0;
if (cmd->sam_task_attr == MSG_ACA_TAG) {
pr_debug("SAM Task Attribute ACA"
" emulation is not supported\n");
return TCM_INVALID_CDB_FIELD;
}
/*
* Used to determine when ORDERED commands should go from
* Dormant to Active status.
*/
cmd->se_ordered_id = atomic_inc_return(&dev->dev_ordered_id);
pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
cmd->se_ordered_id, cmd->sam_task_attr,
dev->transport->name);
return 0;
}
sense_reason_t
target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
{
struct se_device *dev = cmd->se_dev;
sense_reason_t ret;
/*
* 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);
return TCM_INVALID_CDB_FIELD;
}
/*
* 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));
return TCM_OUT_OF_RESOURCES;
}
} 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));
trace_target_sequencer_start(cmd);
/*
* Check for an existing UNIT ATTENTION condition
*/
ret = target_scsi3_ua_check(cmd);
if (ret)
return ret;
ret = target_alua_state_check(cmd);
if (ret)
return ret;
ret = target_check_reservation(cmd);
if (ret) {
cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
return ret;
}
ret = dev->transport->parse_cdb(cmd);
if (ret)
return ret;
ret = transport_check_alloc_task_attr(cmd);
if (ret)
return ret;
cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
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(target_setup_cmd_from_cdb);
/*
* 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)
{
sense_reason_t 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_ACTIVE 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;
cmd->transport_state |= CMD_T_ACTIVE;
/*
* 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)
transport_generic_request_failure(cmd, ret);
return 0;
}
EXPORT_SYMBOL(transport_handle_cdb_direct);
sense_reason_t
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;
/*
* 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");
return TCM_INVALID_CDB_FIELD;
}
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;
}
/*
* target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
* se_cmd + use pre-allocated SGL memory.
*
* @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
* @sgl: struct scatterlist memory for unidirectional mapping
* @sgl_count: scatterlist count for unidirectional mapping
* @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
* @sgl_bidi_count: scatterlist count for bidirectional READ mapping
* @sgl_prot: struct scatterlist memory protection information
* @sgl_prot_count: scatterlist count for protection information
*
* Returns non zero to signal active I/O shutdown failure. All other
* setup exceptions will be returned as a SCSI CHECK_CONDITION response,
* but still return zero here.
*
* This may only be called from process context, and also currently
* assumes internal allocation of fabric payload buffer by target-core.
*/
int target_submit_cmd_map_sgls(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 scatterlist *sgl, u32 sgl_count,
struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
struct scatterlist *sgl_prot, u32 sgl_prot_count)
{
struct se_portal_group *se_tpg;
sense_reason_t rc;
int ret;
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);
if (flags & TARGET_SCF_UNKNOWN_SIZE)
se_cmd->unknown_data_length = 1;
/*
* 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.
*/
ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
if (ret)
return ret;
/*
* 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
*/
rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
if (rc) {
transport_send_check_condition_and_sense(se_cmd, rc, 0);
target_put_sess_cmd(se_sess, se_cmd);
return 0;
}
rc = target_setup_cmd_from_cdb(se_cmd, cdb);
if (rc != 0) {
transport_generic_request_failure(se_cmd, rc);
return 0;
}
/*
* Save pointers for SGLs containing protection information,
* if present.
*/
if (sgl_prot_count) {
se_cmd->t_prot_sg = sgl_prot;
se_cmd->t_prot_nents = sgl_prot_count;
}
/*
* When a non zero sgl_count has been passed perform SGL passthrough
* mapping for pre-allocated fabric memory instead of having target
* core perform an internal SGL allocation..
*/
if (sgl_count != 0) {
BUG_ON(!sgl);
/*
* A work-around for tcm_loop as some userspace code via
* scsi-generic do not memset their associated read buffers,
* so go ahead and do that here for type non-data CDBs. Also
* note that this is currently guaranteed to be a single SGL
* for this case by target core in target_setup_cmd_from_cdb()
* -> transport_generic_cmd_sequencer().
*/
if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
se_cmd->data_direction == DMA_FROM_DEVICE) {
unsigned char *buf = NULL;
if (sgl)
buf = kmap(sg_page(sgl)) + sgl->offset;
if (buf) {
memset(buf, 0, sgl->length);
kunmap(sg_page(sgl));
}
}
rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
sgl_bidi, sgl_bidi_count);
if (rc != 0) {
transport_generic_request_failure(se_cmd, rc);
return 0;
}
}
/*
* Check if we need to delay processing because of ALUA
* Active/NonOptimized primary access state..
*/
core_alua_check_nonop_delay(se_cmd);
transport_handle_cdb_direct(se_cmd);
return 0;
}
EXPORT_SYMBOL(target_submit_cmd_map_sgls);
/*
* 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
*
* Returns non zero to signal active I/O shutdown failure. All other
* setup exceptions will be returned as a SCSI CHECK_CONDITION response,
* but still return zero here.
*
* This may only be called from process context, and also currently
* assumes internal allocation of fabric payload buffer by target-core.
*
* It also assumes interal target core SGL memory allocation.
*/
int 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)
{
return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
unpacked_lun, data_length, task_attr, data_dir,
flags, NULL, 0, NULL, 0, NULL, 0);
}
EXPORT_SYMBOL(target_submit_cmd);
static void target_complete_tmr_failure(struct work_struct *work)
{
struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
se_cmd->se_tfo->queue_tm_rsp(se_cmd);
transport_cmd_check_stop_to_fabric(se_cmd);
}
/**
* target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
* for TMR CDBs
*
* @se_cmd: command descriptor to submit
* @se_sess: associated se_sess for endpoint
* @sense: pointer to SCSI sense buffer
* @unpacked_lun: unpacked LUN to reference for struct se_lun
* @fabric_context: fabric context for TMR req
* @tm_type: Type of TM request
* @gfp: gfp type for caller
* @tag: referenced task tag for TMR_ABORT_TASK
* @flags: submit cmd flags
*
* Callable from all contexts.
**/
int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
unsigned char *sense, u32 unpacked_lun,
void *fabric_tmr_ptr, unsigned char tm_type,
gfp_t gfp, unsigned int tag, int flags)
{
struct se_portal_group *se_tpg;
int ret;
se_tpg = se_sess->se_tpg;
BUG_ON(!se_tpg);
transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
0, DMA_NONE, MSG_SIMPLE_TAG, sense);
/*
* FIXME: Currently expect caller to handle se_cmd->se_tmr_req
* allocation failure.
*/
ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
if (ret < 0)
return -ENOMEM;
if (tm_type == TMR_ABORT_TASK)
se_cmd->se_tmr_req->ref_task_tag = tag;
/* See target_submit_cmd for commentary */
ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
if (ret) {
core_tmr_release_req(se_cmd->se_tmr_req);
return ret;
}
ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
if (ret) {
/*
* For callback during failure handling, push this work off
* to process context with TMR_LUN_DOES_NOT_EXIST status.
*/
INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
schedule_work(&se_cmd->work);
return 0;
}
transport_generic_handle_tmr(se_cmd);
return 0;
}
EXPORT_SYMBOL(target_submit_tmr);
/*
* If the cmd is active, request it to be stopped and sleep until it
* has completed.
*/
bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
{
bool was_active = false;
if (cmd->transport_state & CMD_T_BUSY) {
cmd->transport_state |= CMD_T_REQUEST_STOP;
spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
pr_debug("cmd %p waiting to complete\n", cmd);
wait_for_completion(&cmd->task_stop_comp);
pr_debug("cmd %p stopped successfully\n", cmd);
spin_lock_irqsave(&cmd->t_state_lock, *flags);
cmd->transport_state &= ~CMD_T_REQUEST_STOP;
cmd->transport_state &= ~CMD_T_BUSY;
was_active = true;
}
return was_active;
}
/*
* Handle SAM-esque emulation for generic transport request failures.
*/
void transport_generic_request_failure(struct se_cmd *cmd,
sense_reason_t sense_reason)
{
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 sense_reason: %d\n",
cmd->se_tfo->get_cmd_state(cmd),
cmd->t_state, sense_reason);
pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
(cmd->transport_state & CMD_T_ACTIVE) != 0,
(cmd->transport_state & CMD_T_STOP) != 0,
(cmd->transport_state & CMD_T_SENT) != 0);
/*
* For SAM Task Attribute emulation for failed struct se_cmd
*/
transport_complete_task_attr(cmd);
/*
* Handle special case for COMPARE_AND_WRITE failure, where the
* callback is expected to drop the per device ->caw_mutex.
*/
if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
cmd->transport_complete_callback)
cmd->transport_complete_callback(cmd);
switch (sense_reason) {
case TCM_NON_EXISTENT_LUN:
case TCM_UNSUPPORTED_SCSI_OPCODE:
case TCM_INVALID_CDB_FIELD:
case TCM_INVALID_PARAMETER_LIST:
case TCM_PARAMETER_LIST_LENGTH_ERROR:
case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
case TCM_UNKNOWN_MODE_PAGE:
case TCM_WRITE_PROTECTED:
case TCM_ADDRESS_OUT_OF_RANGE:
case TCM_CHECK_CONDITION_ABORT_CMD:
case TCM_CHECK_CONDITION_UNIT_ATTENTION:
case TCM_CHECK_CONDITION_NOT_READY:
case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
break;
case TCM_OUT_OF_RESOURCES:
sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
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->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);
trace_target_cmd_complete(cmd);
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], sense_reason);
sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
break;
}
ret = transport_send_check_condition_and_sense(cmd, 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);
}
EXPORT_SYMBOL(transport_generic_request_failure);
void __target_execute_cmd(struct se_cmd *cmd)
{
sense_reason_t ret;
if (cmd->execute_cmd) {
ret = cmd->execute_cmd(cmd);
if (ret) {
spin_lock_irq(&cmd->t_state_lock);
cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
spin_unlock_irq(&cmd->t_state_lock);
transport_generic_request_failure(cmd, ret);
}
}
}
static bool target_handle_task_attr(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
return false;
/*
* 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.
*/
switch (cmd->sam_task_attr) {
case 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 false;
case MSG_ORDERED_TAG:
atomic_inc_mb(&dev->dev_ordered_sync);
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);
/*
* Execute an ORDERED command if no other older commands
* exist that need to be completed first.
*/
if (!atomic_read(&dev->simple_cmds))
return false;
break;
default:
/*
* For SIMPLE and UNTAGGED Task Attribute commands
*/
atomic_inc_mb(&dev->simple_cmds);
break;
}
if (atomic_read(&dev->dev_ordered_sync) == 0)
return false;
spin_lock(&dev->delayed_cmd_lock);
list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
spin_unlock(&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 true;
}
void target_execute_cmd(struct se_cmd *cmd)
{
/*
* If the received CDB has aleady been aborted stop processing it here.
*/
if (transport_check_aborted_status(cmd, 1))
return;
/*
* Determine if frontend context caller is requesting the stopping of
* this command for frontend exceptions.
*/
spin_lock_irq(&cmd->t_state_lock);
if (cmd->transport_state & CMD_T_STOP) {
pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
__func__, __LINE__,
cmd->se_tfo->get_task_tag(cmd));
spin_unlock_irq(&cmd->t_state_lock);
complete_all(&cmd->t_transport_stop_comp);
return;
}
cmd->t_state = TRANSPORT_PROCESSING;
cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
spin_unlock_irq(&cmd->t_state_lock);
/*
* Perform WRITE_INSERT of PI using software emulation when backend
* device has PI enabled, if the transport has not already generated
* PI using hardware WRITE_INSERT offload.
*/
if (cmd->prot_op == TARGET_PROT_DOUT_INSERT) {
if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
sbc_dif_generate(cmd);
}
if (target_handle_task_attr(cmd)) {
spin_lock_irq(&cmd->t_state_lock);
cmd->transport_state &= ~CMD_T_BUSY|CMD_T_SENT;
spin_unlock_irq(&cmd->t_state_lock);
return;
}
__target_execute_cmd(cmd);
}
EXPORT_SYMBOL(target_execute_cmd);
/*
* Process all commands up to the last received ORDERED task attribute which
* requires another blocking boundary
*/
static void target_restart_delayed_cmds(struct se_device *dev)
{
for (;;) {
struct se_cmd *cmd;
spin_lock(&dev->delayed_cmd_lock);
if (list_empty(&dev->delayed_cmd_list)) {
spin_unlock(&dev->delayed_cmd_lock);
break;
}
cmd = list_entry(dev->delayed_cmd_list.next,
struct se_cmd, se_delayed_node);
list_del(&cmd->se_delayed_node);
spin_unlock(&dev->delayed_cmd_lock);
__target_execute_cmd(cmd);
if (cmd->sam_task_attr == MSG_ORDERED_TAG)
break;
}
}
/*
* 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;
if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
return;
if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
atomic_dec_mb(&dev->simple_cmds);
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_mb(&dev->dev_ordered_sync);
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);
}
target_restart_delayed_cmds(dev);
}
static void transport_complete_qf(struct se_cmd *cmd)
{
int ret = 0;
transport_complete_task_attr(cmd);
if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
trace_target_cmd_complete(cmd);
ret = cmd->se_tfo->queue_status(cmd);
goto out;
}
switch (cmd->data_direction) {
case DMA_FROM_DEVICE:
trace_target_cmd_complete(cmd);
ret = cmd->se_tfo->queue_data_in(cmd);
break;
case DMA_TO_DEVICE:
if (cmd->se_cmd_flags & SCF_BIDI) {
ret = cmd->se_tfo->queue_data_in(cmd);
if (ret < 0)
break;
}
/* Fall through for DMA_TO_DEVICE */
case DMA_NONE:
trace_target_cmd_complete(cmd);
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_mb(&dev->dev_qf_count);
spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
schedule_work(&cmd->se_dev->qf_work_queue);
}
static bool target_check_read_strip(struct se_cmd *cmd)
{
sense_reason_t rc;
if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
rc = sbc_dif_read_strip(cmd);
if (rc) {
cmd->pi_err = rc;
return true;
}
}
return false;
}
static void target_complete_ok_work(struct work_struct *work)
{
struct se_cmd *cmd = container_of(work, struct se_cmd, work);
int 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.
*/
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 send a sense buffer from
* the struct se_cmd in question.
*/
if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
WARN_ON(!cmd->scsi_status);
ret = transport_send_check_condition_and_sense(
cmd, 0, 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 and COMPARE_AND_WRITE emulation.
*/
if (cmd->transport_complete_callback) {
sense_reason_t rc;
rc = cmd->transport_complete_callback(cmd);
if (!rc && !(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE_POST)) {
return;
} else if (rc) {
ret = transport_send_check_condition_and_sense(cmd,
rc, 0);
if (ret == -EAGAIN || ret == -ENOMEM)
goto queue_full;
transport_lun_remove_cmd(cmd);
transport_cmd_check_stop_to_fabric(cmd);
return;
}
}
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);
/*
* Perform READ_STRIP of PI using software emulation when
* backend had PI enabled, if the transport will not be
* performing hardware READ_STRIP offload.
*/
if (cmd->prot_op == TARGET_PROT_DIN_STRIP &&
target_check_read_strip(cmd)) {
ret = transport_send_check_condition_and_sense(cmd,
cmd->pi_err, 0);
if (ret == -EAGAIN || ret == -ENOMEM)
goto queue_full;
transport_lun_remove_cmd(cmd);
transport_cmd_check_stop_to_fabric(cmd);
return;
}
trace_target_cmd_complete(cmd);
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->se_cmd_flags & SCF_BIDI) {
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:
trace_target_cmd_complete(cmd);
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 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_reset_sgl_orig(struct se_cmd *cmd)
{
/*
* Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
* emulation, and free + reset pointers if necessary..
*/
if (!cmd->t_data_sg_orig)
return;
kfree(cmd->t_data_sg);
cmd->t_data_sg = cmd->t_data_sg_orig;
cmd->t_data_sg_orig = NULL;
cmd->t_data_nents = cmd->t_data_nents_orig;
cmd->t_data_nents_orig = 0;
}
static inline void transport_free_pages(struct se_cmd *cmd)
{
if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
transport_reset_sgl_orig(cmd);
return;
}
transport_reset_sgl_orig(cmd);
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_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
cmd->t_prot_sg = NULL;
cmd->t_prot_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 int transport_release_cmd(struct se_cmd *cmd)
{
BUG_ON(!cmd->se_tfo);
if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
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.
*/
return target_put_sess_cmd(cmd->se_sess, 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 int transport_put_cmd(struct se_cmd *cmd)
{
transport_free_pages(cmd);
return transport_release_cmd(cmd);
}
void *transport_kmap_data_sg(struct se_cmd *cmd)
{
struct scatterlist *sg = cmd->t_data_sg;
struct page **pages;
int i;
/*
* 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;
BUG_ON(!sg);
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));
return;
}
vunmap(cmd->t_data_vmap);
cmd->t_data_vmap = NULL;
}
EXPORT_SYMBOL(transport_kunmap_data_sg);
int
target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
bool zero_page)
{
struct scatterlist *sg;
struct page *page;
gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
unsigned int nent;
int i = 0;
nent = DIV_ROUND_UP(length, PAGE_SIZE);
sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
if (!sg)
return -ENOMEM;
sg_init_table(sg, nent);
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(&sg[i], page, page_len, 0);
length -= page_len;
i++;
}
*sgl = sg;
*nents = nent;
return 0;
out:
while (i > 0) {
i--;
__free_page(sg_page(&sg[i]));
}
kfree(sg);
return -ENOMEM;
}
/*
* Allocate any required resources to execute the command. For writes we
* might not have the payload yet, so notify the fabric via a call to
* ->write_pending instead. Otherwise place it on the execution queue.
*/
sense_reason_t
transport_generic_new_cmd(struct se_cmd *cmd)
{
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) {
bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
if ((cmd->se_cmd_flags & SCF_BIDI) ||
(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
u32 bidi_length;
if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
bidi_length = cmd->t_task_nolb *
cmd->se_dev->dev_attrib.block_size;
else
bidi_length = cmd->data_length;
ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
&cmd->t_bidi_data_nents,
bidi_length, zero_flag);
if (ret < 0)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
if (cmd->prot_op != TARGET_PROT_NORMAL) {
ret = target_alloc_sgl(&cmd->t_prot_sg,
&cmd->t_prot_nents,
cmd->prot_length, true);
if (ret < 0)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
cmd->data_length, zero_flag);
if (ret < 0)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
/*
* If this command is not a write we can execute it right here,
* for write buffers we need to notify the fabric driver first
* and let it call back once the write buffers are ready.
*/
target_add_to_state_list(cmd);
if (cmd->data_direction != DMA_TO_DEVICE) {
target_execute_cmd(cmd);
return 0;
}
transport_cmd_check_stop(cmd, false, true);
ret = cmd->se_tfo->write_pending(cmd);
if (ret == -EAGAIN || ret == -ENOMEM)
goto queue_full;
/* fabric drivers should only return -EAGAIN or -ENOMEM as error */
WARN_ON(ret);
return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
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;
}
EXPORT_SYMBOL(transport_generic_new_cmd);
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);
}
}
int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
{
unsigned long flags;
int ret = 0;
if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
transport_wait_for_tasks(cmd);
ret = transport_release_cmd(cmd);
} else {
if (wait_for_tasks)
transport_wait_for_tasks(cmd);
/*
* Handle WRITE failure case where transport_generic_new_cmd()
* has already added se_cmd to state_list, but fabric has
* failed command before I/O submission.
*/
if (cmd->state_active) {
spin_lock_irqsave(&cmd->t_state_lock, flags);
target_remove_from_state_list(cmd);
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
}
if (cmd->se_lun)
transport_lun_remove_cmd(cmd);
ret = transport_put_cmd(cmd);
}
return ret;
}
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()
*/
int target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd,
bool ack_kref)
{
unsigned long flags;
int ret = 0;
/*
* 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) {
kref_get(&se_cmd->cmd_kref);
se_cmd->se_cmd_flags |= SCF_ACK_KREF;
}
spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
if (se_sess->sess_tearing_down) {
ret = -ESHUTDOWN;
goto out;
}
list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
out:
spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
return ret;
}
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;
if (list_empty(&se_cmd->se_cmd_list)) {
spin_unlock(&se_sess->sess_cmd_lock);
se_cmd->se_tfo->release_cmd(se_cmd);
return;
}
if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
spin_unlock(&se_sess->sess_cmd_lock);
complete(&se_cmd->cmd_wait_comp);
return;
}
list_del(&se_cmd->se_cmd_list);
spin_unlock(&se_sess->sess_cmd_lock);
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)
{
if (!se_sess) {
se_cmd->se_tfo->release_cmd(se_cmd);
return 1;
}
return kref_put_spinlock_irqsave(&se_cmd->cmd_kref, target_release_cmd_kref,
&se_sess->sess_cmd_lock);
}
EXPORT_SYMBOL(target_put_sess_cmd);
/* target_sess_cmd_list_set_waiting - Flag all commands in
* sess_cmd_list to complete cmd_wait_comp. Set
* sess_tearing_down so no more commands are queued.
* @se_sess: session to flag
*/
void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
{
struct se_cmd *se_cmd;
unsigned long flags;
spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
if (se_sess->sess_tearing_down) {
spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
return;
}
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_sess_cmd_list_set_waiting);
/* target_wait_for_sess_cmds - Wait for outstanding descriptors
* @se_sess: session to wait for active I/O
*/
void target_wait_for_sess_cmds(struct se_session *se_sess)
{
struct se_cmd *se_cmd, *tmp_cmd;
unsigned long flags;
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));
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);
}
spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
WARN_ON(!list_empty(&se_sess->sess_cmd_list));
spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
}
EXPORT_SYMBOL(target_wait_for_sess_cmds);
static int transport_clear_lun_ref_thread(void *p)
{
struct se_lun *lun = p;
percpu_ref_kill(&lun->lun_ref);
wait_for_completion(&lun->lun_ref_comp);
complete(&lun->lun_shutdown_comp);
return 0;
}
int transport_clear_lun_ref(struct se_lun *lun)
{
struct task_struct *kt;
kt = kthread_run(transport_clear_lun_ref_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_cmd_flags & SCF_SCSI_TMR_CDB)) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return false;
}
if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return false;
}
if (!(cmd->transport_state & CMD_T_ACTIVE)) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return false;
}
cmd->transport_state |= CMD_T_STOP;
pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
" i_state: %d, t_state: %d, CMD_T_STOP\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);
wait_for_completion(&cmd->t_transport_stop_comp);
spin_lock_irqsave(&cmd->t_state_lock, flags);
cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
pr_debug("wait_for_tasks: Stopped wait_for_completion("
"&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
void transport_err_sector_info(unsigned char *buffer, sector_t bad_sector)
{
/* Place failed LBA in sense data information descriptor 0. */
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 0xc;
buffer[SPC_DESC_TYPE_OFFSET] = 0; /* Information */
buffer[SPC_ADDITIONAL_DESC_LEN_OFFSET] = 0xa;
buffer[SPC_VALIDITY_OFFSET] = 0x80;
/* Descriptor Information: failing sector */
put_unaligned_be64(bad_sector, &buffer[12]);
}
int
transport_send_check_condition_and_sense(struct se_cmd *cmd,
sense_reason_t reason, int from_transport)
{
unsigned char *buffer = cmd->sense_buffer;
unsigned long flags;
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;
/*
* 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_NO_SENSE:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* Not Ready */
buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
/* NO ADDITIONAL SENSE INFORMATION */
buffer[SPC_ASC_KEY_OFFSET] = 0;
buffer[SPC_ASCQ_KEY_OFFSET] = 0;
break;
case TCM_NON_EXISTENT_LUN:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* LOGICAL UNIT NOT SUPPORTED */
buffer[SPC_ASC_KEY_OFFSET] = 0x25;
break;
case TCM_UNSUPPORTED_SCSI_OPCODE:
case TCM_SECTOR_COUNT_TOO_MANY:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* INVALID COMMAND OPERATION CODE */
buffer[SPC_ASC_KEY_OFFSET] = 0x20;
break;
case TCM_UNKNOWN_MODE_PAGE:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* INVALID FIELD IN CDB */
buffer[SPC_ASC_KEY_OFFSET] = 0x24;
break;
case TCM_CHECK_CONDITION_ABORT_CMD:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ABORTED COMMAND */
buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
/* BUS DEVICE RESET FUNCTION OCCURRED */
buffer[SPC_ASC_KEY_OFFSET] = 0x29;
buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
break;
case TCM_INCORRECT_AMOUNT_OF_DATA:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ABORTED COMMAND */
buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
/* WRITE ERROR */
buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
/* NOT ENOUGH UNSOLICITED DATA */
buffer[SPC_ASCQ_KEY_OFFSET] = 0x0d;
break;
case TCM_INVALID_CDB_FIELD:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* INVALID FIELD IN CDB */
buffer[SPC_ASC_KEY_OFFSET] = 0x24;
break;
case TCM_INVALID_PARAMETER_LIST:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* INVALID FIELD IN PARAMETER LIST */
buffer[SPC_ASC_KEY_OFFSET] = 0x26;
break;
case TCM_PARAMETER_LIST_LENGTH_ERROR:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* PARAMETER LIST LENGTH ERROR */
buffer[SPC_ASC_KEY_OFFSET] = 0x1a;
break;
case TCM_UNEXPECTED_UNSOLICITED_DATA:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ABORTED COMMAND */
buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
/* WRITE ERROR */
buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
/* UNEXPECTED_UNSOLICITED_DATA */
buffer[SPC_ASCQ_KEY_OFFSET] = 0x0c;
break;
case TCM_SERVICE_CRC_ERROR:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ABORTED COMMAND */
buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
/* PROTOCOL SERVICE CRC ERROR */
buffer[SPC_ASC_KEY_OFFSET] = 0x47;
/* N/A */
buffer[SPC_ASCQ_KEY_OFFSET] = 0x05;
break;
case TCM_SNACK_REJECTED:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ABORTED COMMAND */
buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
/* READ ERROR */
buffer[SPC_ASC_KEY_OFFSET] = 0x11;
/* FAILED RETRANSMISSION REQUEST */
buffer[SPC_ASCQ_KEY_OFFSET] = 0x13;
break;
case TCM_WRITE_PROTECTED:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* DATA PROTECT */
buffer[SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
/* WRITE PROTECTED */
buffer[SPC_ASC_KEY_OFFSET] = 0x27;
break;
case TCM_ADDRESS_OUT_OF_RANGE:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* LOGICAL BLOCK ADDRESS OUT OF RANGE */
buffer[SPC_ASC_KEY_OFFSET] = 0x21;
break;
case TCM_CHECK_CONDITION_UNIT_ATTENTION:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* UNIT ATTENTION */
buffer[SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
buffer[SPC_ASC_KEY_OFFSET] = asc;
buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
break;
case TCM_CHECK_CONDITION_NOT_READY:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* Not Ready */
buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
transport_get_sense_codes(cmd, &asc, &ascq);
buffer[SPC_ASC_KEY_OFFSET] = asc;
buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
break;
case TCM_MISCOMPARE_VERIFY:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
buffer[SPC_SENSE_KEY_OFFSET] = MISCOMPARE;
/* MISCOMPARE DURING VERIFY OPERATION */
buffer[SPC_ASC_KEY_OFFSET] = 0x1d;
buffer[SPC_ASCQ_KEY_OFFSET] = 0x00;
break;
case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* LOGICAL BLOCK GUARD CHECK FAILED */
buffer[SPC_ASC_KEY_OFFSET] = 0x10;
buffer[SPC_ASCQ_KEY_OFFSET] = 0x01;
transport_err_sector_info(buffer, cmd->bad_sector);
break;
case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
buffer[SPC_ASC_KEY_OFFSET] = 0x10;
buffer[SPC_ASCQ_KEY_OFFSET] = 0x02;
transport_err_sector_info(buffer, cmd->bad_sector);
break;
case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/* ILLEGAL REQUEST */
buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
/* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
buffer[SPC_ASC_KEY_OFFSET] = 0x10;
buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
transport_err_sector_info(buffer, cmd->bad_sector);
break;
case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
default:
/* CURRENT ERROR */
buffer[0] = 0x70;
buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
/*
* Returning ILLEGAL REQUEST would cause immediate IO errors on
* Solaris initiators. Returning NOT READY instead means the
* operations will be retried a finite number of times and we
* can survive intermittent errors.
*/
buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
/* LOGICAL UNIT COMMUNICATION FAILURE */
buffer[SPC_ASC_KEY_OFFSET] = 0x08;
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;
after_reason:
trace_target_cmd_complete(cmd);
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)
{
if (!(cmd->transport_state & CMD_T_ABORTED))
return 0;
/*
* If cmd has been aborted but either no status is to be sent or it has
* already been sent, just return
*/
if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS))
return 1;
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));
cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
cmd->scsi_status = SAM_STAT_TASK_ABORTED;
trace_target_cmd_complete(cmd);
cmd->se_tfo->queue_status(cmd);
return 1;
}
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) {
cmd->transport_state |= CMD_T_ABORTED;
cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
return;
}
}
cmd->scsi_status = SAM_STAT_TASK_ABORTED;
transport_lun_remove_cmd(cmd);
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));
trace_target_cmd_complete(cmd);
cmd->se_tfo->queue_status(cmd);
}
static void target_tmr_work(struct work_struct *work)
{
struct se_cmd *cmd = container_of(work, struct se_cmd, work);
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:
core_tmr_abort_task(dev, tmr, cmd->se_sess);
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);
}
int transport_generic_handle_tmr(
struct se_cmd *cmd)
{
unsigned long flags;
spin_lock_irqsave(&cmd->t_state_lock, flags);
cmd->transport_state |= CMD_T_ACTIVE;
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
INIT_WORK(&cmd->work, target_tmr_work);
queue_work(cmd->se_dev->tmr_wq, &cmd->work);
return 0;
}
EXPORT_SYMBOL(transport_generic_handle_tmr);
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