linux-stable/drivers/target/tcm_fc/tfc_conf.c
Christoph Hellwig 58fc73d10f tcm_fc: Work queue based approach instead of managing own thread and event based mechanism
Problem: Changed from wake_up_interruptible -> wake_up_process and
wait_event_interruptible-> schedule_timeout_interruptible broke the FCoE
target.  Earlier approach of wake_up_interruptible was also looking at
'queue_cnt' which is not necessary, because it increment of 'queue_cnt'
with wake_up_inetrriptible / waker_up_process introduces race condition.

Fix: Instead of fixing the code which used wake_up_process and remove
'queue_cnt', using work_queue based approach is cleaner and acheives
same result. As well, work queue based approach has less programming
overhead and OS manages threads which processes work queues.

This patch is developed by Christoph Hellwig and reviwed+validated by
Kiran Patil.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kiran Patil <kiran.patil@intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-09-16 09:50:09 +00:00

660 lines
16 KiB
C

/*******************************************************************************
* Filename: tcm_fc.c
*
* This file contains the configfs implementation for TCM_fc fabric node.
* Based on tcm_loop_configfs.c
*
* Copyright (c) 2010 Cisco Systems, Inc.
* Copyright (c) 2009,2010 Rising Tide, Inc.
* Copyright (c) 2009,2010 Linux-iSCSI.org
*
* Copyright (c) 2009,2010 Nicholas A. Bellinger <nab@linux-iscsi.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.
****************************************************************************/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/version.h>
#include <generated/utsrelease.h>
#include <linux/utsname.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/kthread.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/configfs.h>
#include <linux/ctype.h>
#include <asm/unaligned.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/libfc.h>
#include <target/target_core_base.h>
#include <target/target_core_transport.h>
#include <target/target_core_fabric_ops.h>
#include <target/target_core_fabric_configfs.h>
#include <target/target_core_fabric_lib.h>
#include <target/target_core_device.h>
#include <target/target_core_tpg.h>
#include <target/target_core_configfs.h>
#include <target/configfs_macros.h>
#include "tcm_fc.h"
struct target_fabric_configfs *ft_configfs;
LIST_HEAD(ft_lport_list);
DEFINE_MUTEX(ft_lport_lock);
unsigned int ft_debug_logging;
module_param_named(debug_logging, ft_debug_logging, int, S_IRUGO|S_IWUSR);
MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels");
/*
* Parse WWN.
* If strict, we require lower-case hex and colon separators to be sure
* the name is the same as what would be generated by ft_format_wwn()
* so the name and wwn are mapped one-to-one.
*/
static ssize_t ft_parse_wwn(const char *name, u64 *wwn, int strict)
{
const char *cp;
char c;
u32 nibble;
u32 byte = 0;
u32 pos = 0;
u32 err;
*wwn = 0;
for (cp = name; cp < &name[FT_NAMELEN - 1]; cp++) {
c = *cp;
if (c == '\n' && cp[1] == '\0')
continue;
if (strict && pos++ == 2 && byte++ < 7) {
pos = 0;
if (c == ':')
continue;
err = 1;
goto fail;
}
if (c == '\0') {
err = 2;
if (strict && byte != 8)
goto fail;
return cp - name;
}
err = 3;
if (isdigit(c))
nibble = c - '0';
else if (isxdigit(c) && (islower(c) || !strict))
nibble = tolower(c) - 'a' + 10;
else
goto fail;
*wwn = (*wwn << 4) | nibble;
}
err = 4;
fail:
pr_debug("err %u len %zu pos %u byte %u\n",
err, cp - name, pos, byte);
return -1;
}
ssize_t ft_format_wwn(char *buf, size_t len, u64 wwn)
{
u8 b[8];
put_unaligned_be64(wwn, b);
return snprintf(buf, len,
"%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x",
b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7]);
}
static ssize_t ft_wwn_show(void *arg, char *buf)
{
u64 *wwn = arg;
ssize_t len;
len = ft_format_wwn(buf, PAGE_SIZE - 2, *wwn);
buf[len++] = '\n';
return len;
}
static ssize_t ft_wwn_store(void *arg, const char *buf, size_t len)
{
ssize_t ret;
u64 wwn;
ret = ft_parse_wwn(buf, &wwn, 0);
if (ret > 0)
*(u64 *)arg = wwn;
return ret;
}
/*
* ACL auth ops.
*/
static ssize_t ft_nacl_show_port_name(
struct se_node_acl *se_nacl,
char *page)
{
struct ft_node_acl *acl = container_of(se_nacl,
struct ft_node_acl, se_node_acl);
return ft_wwn_show(&acl->node_auth.port_name, page);
}
static ssize_t ft_nacl_store_port_name(
struct se_node_acl *se_nacl,
const char *page,
size_t count)
{
struct ft_node_acl *acl = container_of(se_nacl,
struct ft_node_acl, se_node_acl);
return ft_wwn_store(&acl->node_auth.port_name, page, count);
}
TF_NACL_BASE_ATTR(ft, port_name, S_IRUGO | S_IWUSR);
static ssize_t ft_nacl_show_node_name(
struct se_node_acl *se_nacl,
char *page)
{
struct ft_node_acl *acl = container_of(se_nacl,
struct ft_node_acl, se_node_acl);
return ft_wwn_show(&acl->node_auth.node_name, page);
}
static ssize_t ft_nacl_store_node_name(
struct se_node_acl *se_nacl,
const char *page,
size_t count)
{
struct ft_node_acl *acl = container_of(se_nacl,
struct ft_node_acl, se_node_acl);
return ft_wwn_store(&acl->node_auth.node_name, page, count);
}
TF_NACL_BASE_ATTR(ft, node_name, S_IRUGO | S_IWUSR);
static struct configfs_attribute *ft_nacl_base_attrs[] = {
&ft_nacl_port_name.attr,
&ft_nacl_node_name.attr,
NULL,
};
/*
* ACL ops.
*/
/*
* Add ACL for an initiator. The ACL is named arbitrarily.
* The port_name and/or node_name are attributes.
*/
static struct se_node_acl *ft_add_acl(
struct se_portal_group *se_tpg,
struct config_group *group,
const char *name)
{
struct ft_node_acl *acl;
struct ft_tpg *tpg;
u64 wwpn;
u32 q_depth;
pr_debug("add acl %s\n", name);
tpg = container_of(se_tpg, struct ft_tpg, se_tpg);
if (ft_parse_wwn(name, &wwpn, 1) < 0)
return ERR_PTR(-EINVAL);
acl = kzalloc(sizeof(struct ft_node_acl), GFP_KERNEL);
if (!acl)
return ERR_PTR(-ENOMEM);
acl->node_auth.port_name = wwpn;
q_depth = 32; /* XXX bogus default - get from tpg? */
return core_tpg_add_initiator_node_acl(&tpg->se_tpg,
&acl->se_node_acl, name, q_depth);
}
static void ft_del_acl(struct se_node_acl *se_acl)
{
struct se_portal_group *se_tpg = se_acl->se_tpg;
struct ft_tpg *tpg;
struct ft_node_acl *acl = container_of(se_acl,
struct ft_node_acl, se_node_acl);
pr_debug("del acl %s\n",
config_item_name(&se_acl->acl_group.cg_item));
tpg = container_of(se_tpg, struct ft_tpg, se_tpg);
pr_debug("del acl %p se_acl %p tpg %p se_tpg %p\n",
acl, se_acl, tpg, &tpg->se_tpg);
core_tpg_del_initiator_node_acl(&tpg->se_tpg, se_acl, 1);
kfree(acl);
}
struct ft_node_acl *ft_acl_get(struct ft_tpg *tpg, struct fc_rport_priv *rdata)
{
struct ft_node_acl *found = NULL;
struct ft_node_acl *acl;
struct se_portal_group *se_tpg = &tpg->se_tpg;
struct se_node_acl *se_acl;
spin_lock_irq(&se_tpg->acl_node_lock);
list_for_each_entry(se_acl, &se_tpg->acl_node_list, acl_list) {
acl = container_of(se_acl, struct ft_node_acl, se_node_acl);
pr_debug("acl %p port_name %llx\n",
acl, (unsigned long long)acl->node_auth.port_name);
if (acl->node_auth.port_name == rdata->ids.port_name ||
acl->node_auth.node_name == rdata->ids.node_name) {
pr_debug("acl %p port_name %llx matched\n", acl,
(unsigned long long)rdata->ids.port_name);
found = acl;
/* XXX need to hold onto ACL */
break;
}
}
spin_unlock_irq(&se_tpg->acl_node_lock);
return found;
}
struct se_node_acl *ft_tpg_alloc_fabric_acl(struct se_portal_group *se_tpg)
{
struct ft_node_acl *acl;
acl = kzalloc(sizeof(*acl), GFP_KERNEL);
if (!acl) {
pr_err("Unable to allocate struct ft_node_acl\n");
return NULL;
}
pr_debug("acl %p\n", acl);
return &acl->se_node_acl;
}
static void ft_tpg_release_fabric_acl(struct se_portal_group *se_tpg,
struct se_node_acl *se_acl)
{
struct ft_node_acl *acl = container_of(se_acl,
struct ft_node_acl, se_node_acl);
pr_debug("acl %p\n", acl);
kfree(acl);
}
/*
* local_port port_group (tpg) ops.
*/
static struct se_portal_group *ft_add_tpg(
struct se_wwn *wwn,
struct config_group *group,
const char *name)
{
struct ft_lport_acl *lacl;
struct ft_tpg *tpg;
unsigned long index;
int ret;
pr_debug("tcm_fc: add tpg %s\n", name);
/*
* Name must be "tpgt_" followed by the index.
*/
if (strstr(name, "tpgt_") != name)
return NULL;
if (strict_strtoul(name + 5, 10, &index) || index > UINT_MAX)
return NULL;
lacl = container_of(wwn, struct ft_lport_acl, fc_lport_wwn);
tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
if (!tpg)
return NULL;
tpg->index = index;
tpg->lport_acl = lacl;
INIT_LIST_HEAD(&tpg->lun_list);
ret = core_tpg_register(&ft_configfs->tf_ops, wwn, &tpg->se_tpg,
tpg, TRANSPORT_TPG_TYPE_NORMAL);
if (ret < 0) {
kfree(tpg);
return NULL;
}
tpg->workqueue = alloc_workqueue("tcm_fc", 0, 1);
if (!tpg->workqueue) {
kfree(tpg);
return NULL;
}
mutex_lock(&ft_lport_lock);
list_add_tail(&tpg->list, &lacl->tpg_list);
mutex_unlock(&ft_lport_lock);
return &tpg->se_tpg;
}
static void ft_del_tpg(struct se_portal_group *se_tpg)
{
struct ft_tpg *tpg = container_of(se_tpg, struct ft_tpg, se_tpg);
pr_debug("del tpg %s\n",
config_item_name(&tpg->se_tpg.tpg_group.cg_item));
destroy_workqueue(tpg->workqueue);
/* Wait for sessions to be freed thru RCU, for BUG_ON below */
synchronize_rcu();
mutex_lock(&ft_lport_lock);
list_del(&tpg->list);
if (tpg->tport) {
tpg->tport->tpg = NULL;
tpg->tport = NULL;
}
mutex_unlock(&ft_lport_lock);
core_tpg_deregister(se_tpg);
kfree(tpg);
}
/*
* Verify that an lport is configured to use the tcm_fc module, and return
* the target port group that should be used.
*
* The caller holds ft_lport_lock.
*/
struct ft_tpg *ft_lport_find_tpg(struct fc_lport *lport)
{
struct ft_lport_acl *lacl;
struct ft_tpg *tpg;
list_for_each_entry(lacl, &ft_lport_list, list) {
if (lacl->wwpn == lport->wwpn) {
list_for_each_entry(tpg, &lacl->tpg_list, list)
return tpg; /* XXX for now return first entry */
return NULL;
}
}
return NULL;
}
/*
* target config instance ops.
*/
/*
* Add lport to allowed config.
* The name is the WWPN in lower-case ASCII, colon-separated bytes.
*/
static struct se_wwn *ft_add_lport(
struct target_fabric_configfs *tf,
struct config_group *group,
const char *name)
{
struct ft_lport_acl *lacl;
struct ft_lport_acl *old_lacl;
u64 wwpn;
pr_debug("add lport %s\n", name);
if (ft_parse_wwn(name, &wwpn, 1) < 0)
return NULL;
lacl = kzalloc(sizeof(*lacl), GFP_KERNEL);
if (!lacl)
return NULL;
lacl->wwpn = wwpn;
INIT_LIST_HEAD(&lacl->tpg_list);
mutex_lock(&ft_lport_lock);
list_for_each_entry(old_lacl, &ft_lport_list, list) {
if (old_lacl->wwpn == wwpn) {
mutex_unlock(&ft_lport_lock);
kfree(lacl);
return NULL;
}
}
list_add_tail(&lacl->list, &ft_lport_list);
ft_format_wwn(lacl->name, sizeof(lacl->name), wwpn);
mutex_unlock(&ft_lport_lock);
return &lacl->fc_lport_wwn;
}
static void ft_del_lport(struct se_wwn *wwn)
{
struct ft_lport_acl *lacl = container_of(wwn,
struct ft_lport_acl, fc_lport_wwn);
pr_debug("del lport %s\n",
config_item_name(&wwn->wwn_group.cg_item));
mutex_lock(&ft_lport_lock);
list_del(&lacl->list);
mutex_unlock(&ft_lport_lock);
kfree(lacl);
}
static ssize_t ft_wwn_show_attr_version(
struct target_fabric_configfs *tf,
char *page)
{
return sprintf(page, "TCM FC " FT_VERSION " on %s/%s on "
""UTS_RELEASE"\n", utsname()->sysname, utsname()->machine);
}
TF_WWN_ATTR_RO(ft, version);
static struct configfs_attribute *ft_wwn_attrs[] = {
&ft_wwn_version.attr,
NULL,
};
static char *ft_get_fabric_name(void)
{
return "fc";
}
static char *ft_get_fabric_wwn(struct se_portal_group *se_tpg)
{
struct ft_tpg *tpg = se_tpg->se_tpg_fabric_ptr;
return tpg->lport_acl->name;
}
static u16 ft_get_tag(struct se_portal_group *se_tpg)
{
struct ft_tpg *tpg = se_tpg->se_tpg_fabric_ptr;
/*
* This tag is used when forming SCSI Name identifier in EVPD=1 0x83
* to represent the SCSI Target Port.
*/
return tpg->index;
}
static u32 ft_get_default_depth(struct se_portal_group *se_tpg)
{
return 1;
}
static int ft_check_false(struct se_portal_group *se_tpg)
{
return 0;
}
static void ft_set_default_node_attr(struct se_node_acl *se_nacl)
{
}
static u16 ft_get_fabric_sense_len(void)
{
return 0;
}
static u16 ft_set_fabric_sense_len(struct se_cmd *se_cmd, u32 sense_len)
{
return 0;
}
static u32 ft_tpg_get_inst_index(struct se_portal_group *se_tpg)
{
struct ft_tpg *tpg = se_tpg->se_tpg_fabric_ptr;
return tpg->index;
}
static struct target_core_fabric_ops ft_fabric_ops = {
.get_fabric_name = ft_get_fabric_name,
.get_fabric_proto_ident = fc_get_fabric_proto_ident,
.tpg_get_wwn = ft_get_fabric_wwn,
.tpg_get_tag = ft_get_tag,
.tpg_get_default_depth = ft_get_default_depth,
.tpg_get_pr_transport_id = fc_get_pr_transport_id,
.tpg_get_pr_transport_id_len = fc_get_pr_transport_id_len,
.tpg_parse_pr_out_transport_id = fc_parse_pr_out_transport_id,
.tpg_check_demo_mode = ft_check_false,
.tpg_check_demo_mode_cache = ft_check_false,
.tpg_check_demo_mode_write_protect = ft_check_false,
.tpg_check_prod_mode_write_protect = ft_check_false,
.tpg_alloc_fabric_acl = ft_tpg_alloc_fabric_acl,
.tpg_release_fabric_acl = ft_tpg_release_fabric_acl,
.tpg_get_inst_index = ft_tpg_get_inst_index,
.check_stop_free = ft_check_stop_free,
.release_cmd = ft_release_cmd,
.shutdown_session = ft_sess_shutdown,
.close_session = ft_sess_close,
.stop_session = ft_sess_stop,
.fall_back_to_erl0 = ft_sess_set_erl0,
.sess_logged_in = ft_sess_logged_in,
.sess_get_index = ft_sess_get_index,
.sess_get_initiator_sid = NULL,
.write_pending = ft_write_pending,
.write_pending_status = ft_write_pending_status,
.set_default_node_attributes = ft_set_default_node_attr,
.get_task_tag = ft_get_task_tag,
.get_cmd_state = ft_get_cmd_state,
.queue_data_in = ft_queue_data_in,
.queue_status = ft_queue_status,
.queue_tm_rsp = ft_queue_tm_resp,
.get_fabric_sense_len = ft_get_fabric_sense_len,
.set_fabric_sense_len = ft_set_fabric_sense_len,
.is_state_remove = ft_is_state_remove,
/*
* Setup function pointers for generic logic in
* target_core_fabric_configfs.c
*/
.fabric_make_wwn = &ft_add_lport,
.fabric_drop_wwn = &ft_del_lport,
.fabric_make_tpg = &ft_add_tpg,
.fabric_drop_tpg = &ft_del_tpg,
.fabric_post_link = NULL,
.fabric_pre_unlink = NULL,
.fabric_make_np = NULL,
.fabric_drop_np = NULL,
.fabric_make_nodeacl = &ft_add_acl,
.fabric_drop_nodeacl = &ft_del_acl,
};
int ft_register_configfs(void)
{
struct target_fabric_configfs *fabric;
int ret;
/*
* Register the top level struct config_item_type with TCM core
*/
fabric = target_fabric_configfs_init(THIS_MODULE, "fc");
if (IS_ERR(fabric)) {
pr_err("%s: target_fabric_configfs_init() failed!\n",
__func__);
return PTR_ERR(fabric);
}
fabric->tf_ops = ft_fabric_ops;
/* Allowing support for task_sg_chaining */
fabric->tf_ops.task_sg_chaining = 1;
/*
* Setup default attribute lists for various fabric->tf_cit_tmpl
*/
TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = ft_wwn_attrs;
TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = NULL;
TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
TF_CIT_TMPL(fabric)->tfc_tpg_nacl_base_cit.ct_attrs =
ft_nacl_base_attrs;
TF_CIT_TMPL(fabric)->tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
TF_CIT_TMPL(fabric)->tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
TF_CIT_TMPL(fabric)->tfc_tpg_nacl_param_cit.ct_attrs = NULL;
/*
* register the fabric for use within TCM
*/
ret = target_fabric_configfs_register(fabric);
if (ret < 0) {
pr_debug("target_fabric_configfs_register() for"
" FC Target failed!\n");
target_fabric_configfs_free(fabric);
return -1;
}
/*
* Setup our local pointer to *fabric.
*/
ft_configfs = fabric;
return 0;
}
void ft_deregister_configfs(void)
{
if (!ft_configfs)
return;
target_fabric_configfs_deregister(ft_configfs);
ft_configfs = NULL;
}
static struct notifier_block ft_notifier = {
.notifier_call = ft_lport_notify
};
static int __init ft_init(void)
{
if (ft_register_configfs())
return -1;
if (fc_fc4_register_provider(FC_TYPE_FCP, &ft_prov)) {
ft_deregister_configfs();
return -1;
}
blocking_notifier_chain_register(&fc_lport_notifier_head, &ft_notifier);
fc_lport_iterate(ft_lport_add, NULL);
return 0;
}
static void __exit ft_exit(void)
{
blocking_notifier_chain_unregister(&fc_lport_notifier_head,
&ft_notifier);
fc_fc4_deregister_provider(FC_TYPE_FCP, &ft_prov);
fc_lport_iterate(ft_lport_del, NULL);
ft_deregister_configfs();
synchronize_rcu();
}
MODULE_DESCRIPTION("FC TCM fabric driver " FT_VERSION);
MODULE_LICENSE("GPL");
module_init(ft_init);
module_exit(ft_exit);