linux/drivers/target/target_core_ua.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

333 lines
9.1 KiB
C

/*******************************************************************************
* Filename: target_core_ua.c
*
* This file contains logic for SPC-3 Unit Attention emulation
*
* 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 <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <target/target_core_base.h>
#include <target/target_core_device.h>
#include <target/target_core_transport.h>
#include <target/target_core_fabric_ops.h>
#include <target/target_core_configfs.h>
#include "target_core_alua.h"
#include "target_core_hba.h"
#include "target_core_pr.h"
#include "target_core_ua.h"
int core_scsi3_ua_check(
struct se_cmd *cmd,
unsigned char *cdb)
{
struct se_dev_entry *deve;
struct se_session *sess = cmd->se_sess;
struct se_node_acl *nacl;
if (!sess)
return 0;
nacl = sess->se_node_acl;
if (!nacl)
return 0;
deve = &nacl->device_list[cmd->orig_fe_lun];
if (!atomic_read(&deve->ua_count))
return 0;
/*
* From sam4r14, section 5.14 Unit attention condition:
*
* a) if an INQUIRY command enters the enabled command state, the
* device server shall process the INQUIRY command and shall neither
* report nor clear any unit attention condition;
* b) if a REPORT LUNS command enters the enabled command state, the
* device server shall process the REPORT LUNS command and shall not
* report any unit attention condition;
* e) if a REQUEST SENSE command enters the enabled command state while
* a unit attention condition exists for the SCSI initiator port
* associated with the I_T nexus on which the REQUEST SENSE command
* was received, then the device server shall process the command
* and either:
*/
switch (cdb[0]) {
case INQUIRY:
case REPORT_LUNS:
case REQUEST_SENSE:
return 0;
default:
return -EINVAL;
}
return -EINVAL;
}
int core_scsi3_ua_allocate(
struct se_node_acl *nacl,
u32 unpacked_lun,
u8 asc,
u8 ascq)
{
struct se_dev_entry *deve;
struct se_ua *ua, *ua_p, *ua_tmp;
/*
* PASSTHROUGH OPS
*/
if (!nacl)
return -EINVAL;
ua = kmem_cache_zalloc(se_ua_cache, GFP_ATOMIC);
if (!ua) {
pr_err("Unable to allocate struct se_ua\n");
return -ENOMEM;
}
INIT_LIST_HEAD(&ua->ua_dev_list);
INIT_LIST_HEAD(&ua->ua_nacl_list);
ua->ua_nacl = nacl;
ua->ua_asc = asc;
ua->ua_ascq = ascq;
spin_lock_irq(&nacl->device_list_lock);
deve = &nacl->device_list[unpacked_lun];
spin_lock(&deve->ua_lock);
list_for_each_entry_safe(ua_p, ua_tmp, &deve->ua_list, ua_nacl_list) {
/*
* Do not report the same UNIT ATTENTION twice..
*/
if ((ua_p->ua_asc == asc) && (ua_p->ua_ascq == ascq)) {
spin_unlock(&deve->ua_lock);
spin_unlock_irq(&nacl->device_list_lock);
kmem_cache_free(se_ua_cache, ua);
return 0;
}
/*
* Attach the highest priority Unit Attention to
* the head of the list following sam4r14,
* Section 5.14 Unit Attention Condition:
*
* POWER ON, RESET, OR BUS DEVICE RESET OCCURRED highest
* POWER ON OCCURRED or
* DEVICE INTERNAL RESET
* SCSI BUS RESET OCCURRED or
* MICROCODE HAS BEEN CHANGED or
* protocol specific
* BUS DEVICE RESET FUNCTION OCCURRED
* I_T NEXUS LOSS OCCURRED
* COMMANDS CLEARED BY POWER LOSS NOTIFICATION
* all others Lowest
*
* Each of the ASCQ codes listed above are defined in
* the 29h ASC family, see spc4r17 Table D.1
*/
if (ua_p->ua_asc == 0x29) {
if ((asc == 0x29) && (ascq > ua_p->ua_ascq))
list_add(&ua->ua_nacl_list,
&deve->ua_list);
else
list_add_tail(&ua->ua_nacl_list,
&deve->ua_list);
} else if (ua_p->ua_asc == 0x2a) {
/*
* Incoming Family 29h ASCQ codes will override
* Family 2AHh ASCQ codes for Unit Attention condition.
*/
if ((asc == 0x29) || (ascq > ua_p->ua_asc))
list_add(&ua->ua_nacl_list,
&deve->ua_list);
else
list_add_tail(&ua->ua_nacl_list,
&deve->ua_list);
} else
list_add_tail(&ua->ua_nacl_list,
&deve->ua_list);
spin_unlock(&deve->ua_lock);
spin_unlock_irq(&nacl->device_list_lock);
atomic_inc(&deve->ua_count);
smp_mb__after_atomic_inc();
return 0;
}
list_add_tail(&ua->ua_nacl_list, &deve->ua_list);
spin_unlock(&deve->ua_lock);
spin_unlock_irq(&nacl->device_list_lock);
pr_debug("[%s]: Allocated UNIT ATTENTION, mapped LUN: %u, ASC:"
" 0x%02x, ASCQ: 0x%02x\n",
nacl->se_tpg->se_tpg_tfo->get_fabric_name(), unpacked_lun,
asc, ascq);
atomic_inc(&deve->ua_count);
smp_mb__after_atomic_inc();
return 0;
}
void core_scsi3_ua_release_all(
struct se_dev_entry *deve)
{
struct se_ua *ua, *ua_p;
spin_lock(&deve->ua_lock);
list_for_each_entry_safe(ua, ua_p, &deve->ua_list, ua_nacl_list) {
list_del(&ua->ua_nacl_list);
kmem_cache_free(se_ua_cache, ua);
atomic_dec(&deve->ua_count);
smp_mb__after_atomic_dec();
}
spin_unlock(&deve->ua_lock);
}
void core_scsi3_ua_for_check_condition(
struct se_cmd *cmd,
u8 *asc,
u8 *ascq)
{
struct se_device *dev = cmd->se_dev;
struct se_dev_entry *deve;
struct se_session *sess = cmd->se_sess;
struct se_node_acl *nacl;
struct se_ua *ua = NULL, *ua_p;
int head = 1;
if (!sess)
return;
nacl = sess->se_node_acl;
if (!nacl)
return;
spin_lock_irq(&nacl->device_list_lock);
deve = &nacl->device_list[cmd->orig_fe_lun];
if (!atomic_read(&deve->ua_count)) {
spin_unlock_irq(&nacl->device_list_lock);
return;
}
/*
* The highest priority Unit Attentions are placed at the head of the
* struct se_dev_entry->ua_list, and will be returned in CHECK_CONDITION +
* sense data for the received CDB.
*/
spin_lock(&deve->ua_lock);
list_for_each_entry_safe(ua, ua_p, &deve->ua_list, ua_nacl_list) {
/*
* For ua_intlck_ctrl code not equal to 00b, only report the
* highest priority UNIT_ATTENTION and ASC/ASCQ without
* clearing it.
*/
if (dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl != 0) {
*asc = ua->ua_asc;
*ascq = ua->ua_ascq;
break;
}
/*
* Otherwise for the default 00b, release the UNIT ATTENTION
* condition. Return the ASC/ASCQ of the highest priority UA
* (head of the list) in the outgoing CHECK_CONDITION + sense.
*/
if (head) {
*asc = ua->ua_asc;
*ascq = ua->ua_ascq;
head = 0;
}
list_del(&ua->ua_nacl_list);
kmem_cache_free(se_ua_cache, ua);
atomic_dec(&deve->ua_count);
smp_mb__after_atomic_dec();
}
spin_unlock(&deve->ua_lock);
spin_unlock_irq(&nacl->device_list_lock);
pr_debug("[%s]: %s UNIT ATTENTION condition with"
" INTLCK_CTRL: %d, mapped LUN: %u, got CDB: 0x%02x"
" reported ASC: 0x%02x, ASCQ: 0x%02x\n",
nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
(dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl != 0) ? "Reporting" :
"Releasing", dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl,
cmd->orig_fe_lun, cmd->t_task_cdb[0], *asc, *ascq);
}
int core_scsi3_ua_clear_for_request_sense(
struct se_cmd *cmd,
u8 *asc,
u8 *ascq)
{
struct se_dev_entry *deve;
struct se_session *sess = cmd->se_sess;
struct se_node_acl *nacl;
struct se_ua *ua = NULL, *ua_p;
int head = 1;
if (!sess)
return -EINVAL;
nacl = sess->se_node_acl;
if (!nacl)
return -EINVAL;
spin_lock_irq(&nacl->device_list_lock);
deve = &nacl->device_list[cmd->orig_fe_lun];
if (!atomic_read(&deve->ua_count)) {
spin_unlock_irq(&nacl->device_list_lock);
return -EPERM;
}
/*
* The highest priority Unit Attentions are placed at the head of the
* struct se_dev_entry->ua_list. The First (and hence highest priority)
* ASC/ASCQ will be returned in REQUEST_SENSE payload data for the
* matching struct se_lun.
*
* Once the returning ASC/ASCQ values are set, we go ahead and
* release all of the Unit Attention conditions for the associated
* struct se_lun.
*/
spin_lock(&deve->ua_lock);
list_for_each_entry_safe(ua, ua_p, &deve->ua_list, ua_nacl_list) {
if (head) {
*asc = ua->ua_asc;
*ascq = ua->ua_ascq;
head = 0;
}
list_del(&ua->ua_nacl_list);
kmem_cache_free(se_ua_cache, ua);
atomic_dec(&deve->ua_count);
smp_mb__after_atomic_dec();
}
spin_unlock(&deve->ua_lock);
spin_unlock_irq(&nacl->device_list_lock);
pr_debug("[%s]: Released UNIT ATTENTION condition, mapped"
" LUN: %u, got REQUEST_SENSE reported ASC: 0x%02x,"
" ASCQ: 0x%02x\n", nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
cmd->orig_fe_lun, *asc, *ascq);
return (head) ? -EPERM : 0;
}