linux/drivers/target/target_core_tmr.c
Andy Grover 6708bb27bb target: Follow up core updates from AGrover and HCH (round 4)
This patch contains the squashed version of forth round series cleanups
from Andy and Christoph following the post heavy lifting in the preceeding:
'Eliminate usage of struct se_mem' and 'Make all control CDBs scatter-gather'
changes.  This also includes a conversion of target core and the v3.0
mainline fabric modules (loopback and tcm_fc) to use pr_debug and the
CONFIG_DYNAMIC_DEBUG infrastructure!

These have been squashed into this third and final round for v3.1.

target: Remove ifdeffed code in t_g_process_write
target: Remove direct ramdisk code
target: Rename task_sg_num to task_sg_nents
target: Remove custom debug macros for pr_debug. Use pr_err().
target: Remove custom debug macros in mainline fabrics
target: Set WSNZ=1 in block limits VPD. Abort if WRITE_SAME sectors = 0
target: Remove transport do_se_mem_map callback
target: Further simplify transport_free_pages
target: Redo task allocation return value handling
target: Remove extra parentheses
target: change alloc_task call to take *cdb, not *cmd

(nab: Fix bogus struct file assignments in fd_do_readv and fd_do_writev)

Signed-off-by: Andy Grover <agrover@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:48 +00:00

382 lines
12 KiB
C

/*******************************************************************************
* Filename: target_core_tmr.c
*
* This file contains SPC-3 task management infrastructure
*
* Copyright (c) 2009,2010 Rising Tide Systems
* Copyright (c) 2009,2010 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/version.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/list.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <target/target_core_base.h>
#include <target/target_core_device.h>
#include <target/target_core_tmr.h>
#include <target/target_core_transport.h>
#include <target/target_core_fabric_ops.h>
#include <target/target_core_configfs.h>
#include "target_core_alua.h"
#include "target_core_pr.h"
struct se_tmr_req *core_tmr_alloc_req(
struct se_cmd *se_cmd,
void *fabric_tmr_ptr,
u8 function)
{
struct se_tmr_req *tmr;
tmr = kmem_cache_zalloc(se_tmr_req_cache, (in_interrupt()) ?
GFP_ATOMIC : GFP_KERNEL);
if (!tmr) {
pr_err("Unable to allocate struct se_tmr_req\n");
return ERR_PTR(-ENOMEM);
}
tmr->task_cmd = se_cmd;
tmr->fabric_tmr_ptr = fabric_tmr_ptr;
tmr->function = function;
INIT_LIST_HEAD(&tmr->tmr_list);
return tmr;
}
EXPORT_SYMBOL(core_tmr_alloc_req);
void core_tmr_release_req(
struct se_tmr_req *tmr)
{
struct se_device *dev = tmr->tmr_dev;
if (!dev) {
kmem_cache_free(se_tmr_req_cache, tmr);
return;
}
spin_lock_irq(&dev->se_tmr_lock);
list_del(&tmr->tmr_list);
spin_unlock_irq(&dev->se_tmr_lock);
kmem_cache_free(se_tmr_req_cache, tmr);
}
static void core_tmr_handle_tas_abort(
struct se_node_acl *tmr_nacl,
struct se_cmd *cmd,
int tas,
int fe_count)
{
if (!fe_count) {
transport_cmd_finish_abort(cmd, 1);
return;
}
/*
* TASK ABORTED status (TAS) bit support
*/
if ((tmr_nacl &&
(tmr_nacl == cmd->se_sess->se_node_acl)) || tas)
transport_send_task_abort(cmd);
transport_cmd_finish_abort(cmd, 0);
}
int core_tmr_lun_reset(
struct se_device *dev,
struct se_tmr_req *tmr,
struct list_head *preempt_and_abort_list,
struct se_cmd *prout_cmd)
{
struct se_cmd *cmd, *tcmd;
struct se_node_acl *tmr_nacl = NULL;
struct se_portal_group *tmr_tpg = NULL;
struct se_queue_obj *qobj = &dev->dev_queue_obj;
struct se_tmr_req *tmr_p, *tmr_pp;
struct se_task *task, *task_tmp;
unsigned long flags;
int fe_count, tas;
/*
* TASK_ABORTED status bit, this is configurable via ConfigFS
* struct se_device attributes. spc4r17 section 7.4.6 Control mode page
*
* A task aborted status (TAS) bit set to zero specifies that aborted
* tasks shall be terminated by the device server without any response
* to the application client. A TAS bit set to one specifies that tasks
* aborted by the actions of an I_T nexus other than the I_T nexus on
* which the command was received shall be completed with TASK ABORTED
* status (see SAM-4).
*/
tas = dev->se_sub_dev->se_dev_attrib.emulate_tas;
/*
* Determine if this se_tmr is coming from a $FABRIC_MOD
* or struct se_device passthrough..
*/
if (tmr && tmr->task_cmd && tmr->task_cmd->se_sess) {
tmr_nacl = tmr->task_cmd->se_sess->se_node_acl;
tmr_tpg = tmr->task_cmd->se_sess->se_tpg;
if (tmr_nacl && tmr_tpg) {
pr_debug("LUN_RESET: TMR caller fabric: %s"
" initiator port %s\n",
tmr_tpg->se_tpg_tfo->get_fabric_name(),
tmr_nacl->initiatorname);
}
}
pr_debug("LUN_RESET: %s starting for [%s], tas: %d\n",
(preempt_and_abort_list) ? "Preempt" : "TMR",
dev->transport->name, tas);
/*
* Release all pending and outgoing TMRs aside from the received
* LUN_RESET tmr..
*/
spin_lock_irq(&dev->se_tmr_lock);
list_for_each_entry_safe(tmr_p, tmr_pp, &dev->dev_tmr_list, tmr_list) {
/*
* Allow the received TMR to return with FUNCTION_COMPLETE.
*/
if (tmr && (tmr_p == tmr))
continue;
cmd = tmr_p->task_cmd;
if (!cmd) {
pr_err("Unable to locate struct se_cmd for TMR\n");
continue;
}
/*
* If this function was called with a valid pr_res_key
* parameter (eg: for PROUT PREEMPT_AND_ABORT service action
* skip non regisration key matching TMRs.
*/
if (preempt_and_abort_list &&
(core_scsi3_check_cdb_abort_and_preempt(
preempt_and_abort_list, cmd) != 0))
continue;
spin_unlock_irq(&dev->se_tmr_lock);
spin_lock_irqsave(&cmd->t_state_lock, flags);
if (!atomic_read(&cmd->t_transport_active)) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
spin_lock_irq(&dev->se_tmr_lock);
continue;
}
if (cmd->t_state == TRANSPORT_ISTATE_PROCESSING) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
spin_lock_irq(&dev->se_tmr_lock);
continue;
}
pr_debug("LUN_RESET: %s releasing TMR %p Function: 0x%02x,"
" Response: 0x%02x, t_state: %d\n",
(preempt_and_abort_list) ? "Preempt" : "", tmr_p,
tmr_p->function, tmr_p->response, cmd->t_state);
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
transport_cmd_finish_abort_tmr(cmd);
spin_lock_irq(&dev->se_tmr_lock);
}
spin_unlock_irq(&dev->se_tmr_lock);
/*
* Complete outstanding struct se_task CDBs with TASK_ABORTED SAM status.
* This is following sam4r17, section 5.6 Aborting commands, Table 38
* for TMR LUN_RESET:
*
* a) "Yes" indicates that each command that is aborted on an I_T nexus
* other than the one that caused the SCSI device condition is
* completed with TASK ABORTED status, if the TAS bit is set to one in
* the Control mode page (see SPC-4). "No" indicates that no status is
* returned for aborted commands.
*
* d) If the logical unit reset is caused by a particular I_T nexus
* (e.g., by a LOGICAL UNIT RESET task management function), then "yes"
* (TASK_ABORTED status) applies.
*
* Otherwise (e.g., if triggered by a hard reset), "no"
* (no TASK_ABORTED SAM status) applies.
*
* Note that this seems to be independent of TAS (Task Aborted Status)
* in the Control Mode Page.
*/
spin_lock_irqsave(&dev->execute_task_lock, flags);
list_for_each_entry_safe(task, task_tmp, &dev->state_task_list,
t_state_list) {
if (!task->task_se_cmd) {
pr_err("task->task_se_cmd is NULL!\n");
continue;
}
cmd = task->task_se_cmd;
/*
* For PREEMPT_AND_ABORT usage, only process commands
* with a matching reservation key.
*/
if (preempt_and_abort_list &&
(core_scsi3_check_cdb_abort_and_preempt(
preempt_and_abort_list, cmd) != 0))
continue;
/*
* Not aborting PROUT PREEMPT_AND_ABORT CDB..
*/
if (prout_cmd == cmd)
continue;
list_del(&task->t_state_list);
atomic_set(&task->task_state_active, 0);
spin_unlock_irqrestore(&dev->execute_task_lock, flags);
spin_lock_irqsave(&cmd->t_state_lock, flags);
pr_debug("LUN_RESET: %s cmd: %p task: %p"
" ITT/CmdSN: 0x%08x/0x%08x, i_state: %d, t_state/"
"def_t_state: %d/%d cdb: 0x%02x\n",
(preempt_and_abort_list) ? "Preempt" : "", cmd, task,
cmd->se_tfo->get_task_tag(cmd), 0,
cmd->se_tfo->get_cmd_state(cmd), cmd->t_state,
cmd->deferred_t_state, cmd->t_task_cdb[0]);
pr_debug("LUN_RESET: ITT[0x%08x] - pr_res_key: 0x%016Lx"
" t_task_cdbs: %d t_task_cdbs_left: %d"
" t_task_cdbs_sent: %d -- t_transport_active: %d"
" t_transport_stop: %d t_transport_sent: %d\n",
cmd->se_tfo->get_task_tag(cmd), cmd->pr_res_key,
cmd->t_task_list_num,
atomic_read(&cmd->t_task_cdbs_left),
atomic_read(&cmd->t_task_cdbs_sent),
atomic_read(&cmd->t_transport_active),
atomic_read(&cmd->t_transport_stop),
atomic_read(&cmd->t_transport_sent));
if (atomic_read(&task->task_active)) {
atomic_set(&task->task_stop, 1);
spin_unlock_irqrestore(
&cmd->t_state_lock, flags);
pr_debug("LUN_RESET: Waiting for task: %p to shutdown"
" for dev: %p\n", task, dev);
wait_for_completion(&task->task_stop_comp);
pr_debug("LUN_RESET Completed task: %p shutdown for"
" dev: %p\n", task, dev);
spin_lock_irqsave(&cmd->t_state_lock, flags);
atomic_dec(&cmd->t_task_cdbs_left);
atomic_set(&task->task_active, 0);
atomic_set(&task->task_stop, 0);
} else {
if (atomic_read(&task->task_execute_queue) != 0)
transport_remove_task_from_execute_queue(task, dev);
}
__transport_stop_task_timer(task, &flags);
if (!atomic_dec_and_test(&cmd->t_task_cdbs_ex_left)) {
spin_unlock_irqrestore(
&cmd->t_state_lock, flags);
pr_debug("LUN_RESET: Skipping task: %p, dev: %p for"
" t_task_cdbs_ex_left: %d\n", task, dev,
atomic_read(&cmd->t_task_cdbs_ex_left));
spin_lock_irqsave(&dev->execute_task_lock, flags);
continue;
}
fe_count = atomic_read(&cmd->t_fe_count);
if (atomic_read(&cmd->t_transport_active)) {
pr_debug("LUN_RESET: got t_transport_active = 1 for"
" task: %p, t_fe_count: %d dev: %p\n", task,
fe_count, dev);
atomic_set(&cmd->t_transport_aborted, 1);
spin_unlock_irqrestore(&cmd->t_state_lock,
flags);
core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count);
spin_lock_irqsave(&dev->execute_task_lock, flags);
continue;
}
pr_debug("LUN_RESET: Got t_transport_active = 0 for task: %p,"
" t_fe_count: %d dev: %p\n", task, fe_count, dev);
atomic_set(&cmd->t_transport_aborted, 1);
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count);
spin_lock_irqsave(&dev->execute_task_lock, flags);
}
spin_unlock_irqrestore(&dev->execute_task_lock, flags);
/*
* Release all commands remaining in the struct se_device cmd queue.
*
* This follows the same logic as above for the struct se_device
* struct se_task state list, where commands are returned with
* TASK_ABORTED status, if there is an outstanding $FABRIC_MOD
* reference, otherwise the struct se_cmd is released.
*/
spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
list_for_each_entry_safe(cmd, tcmd, &qobj->qobj_list, se_queue_node) {
/*
* For PREEMPT_AND_ABORT usage, only process commands
* with a matching reservation key.
*/
if (preempt_and_abort_list &&
(core_scsi3_check_cdb_abort_and_preempt(
preempt_and_abort_list, cmd) != 0))
continue;
/*
* Not aborting PROUT PREEMPT_AND_ABORT CDB..
*/
if (prout_cmd == cmd)
continue;
atomic_dec(&cmd->t_transport_queue_active);
atomic_dec(&qobj->queue_cnt);
list_del(&cmd->se_queue_node);
spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
pr_debug("LUN_RESET: %s from Device Queue: cmd: %p t_state:"
" %d t_fe_count: %d\n", (preempt_and_abort_list) ?
"Preempt" : "", cmd, cmd->t_state,
atomic_read(&cmd->t_fe_count));
/*
* Signal that the command has failed via cmd->se_cmd_flags,
*/
transport_new_cmd_failure(cmd);
core_tmr_handle_tas_abort(tmr_nacl, cmd, tas,
atomic_read(&cmd->t_fe_count));
spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
}
spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
/*
* Clear any legacy SPC-2 reservation when called during
* LOGICAL UNIT RESET
*/
if (!preempt_and_abort_list &&
(dev->dev_flags & DF_SPC2_RESERVATIONS)) {
spin_lock(&dev->dev_reservation_lock);
dev->dev_reserved_node_acl = NULL;
dev->dev_flags &= ~DF_SPC2_RESERVATIONS;
spin_unlock(&dev->dev_reservation_lock);
pr_debug("LUN_RESET: SCSI-2 Released reservation\n");
}
spin_lock_irq(&dev->stats_lock);
dev->num_resets++;
spin_unlock_irq(&dev->stats_lock);
pr_debug("LUN_RESET: %s for [%s] Complete\n",
(preempt_and_abort_list) ? "Preempt" : "TMR",
dev->transport->name);
return 0;
}