diff options
Diffstat (limited to 'drivers/target/target_core_hba.c')
| -rw-r--r-- | drivers/target/target_core_hba.c | 128 |
1 files changed, 69 insertions, 59 deletions
diff --git a/drivers/target/target_core_hba.c b/drivers/target/target_core_hba.c index d2616cd48f1e..d508b343ba7b 100644 --- a/drivers/target/target_core_hba.c +++ b/drivers/target/target_core_hba.c @@ -1,26 +1,13 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /******************************************************************************* * Filename: target_core_hba.c * * This file contains the TCM HBA Transport related functions. * - * (c) Copyright 2003-2012 RisingTide Systems LLC. + * (c) Copyright 2003-2013 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> @@ -39,63 +26,83 @@ #include "target_core_internal.h" -static LIST_HEAD(subsystem_list); -static DEFINE_MUTEX(subsystem_mutex); +static LIST_HEAD(backend_list); +static DEFINE_MUTEX(backend_mutex); static u32 hba_id_counter; static DEFINE_SPINLOCK(hba_lock); static LIST_HEAD(hba_list); -int transport_subsystem_register(struct se_subsystem_api *sub_api) -{ - struct se_subsystem_api *s; - - INIT_LIST_HEAD(&sub_api->sub_api_list); - mutex_lock(&subsystem_mutex); - list_for_each_entry(s, &subsystem_list, sub_api_list) { - if (!strcmp(s->name, sub_api->name)) { - pr_err("%p is already registered with" - " duplicate name %s, unable to process" - " request\n", s, s->name); - mutex_unlock(&subsystem_mutex); +int transport_backend_register(const struct target_backend_ops *ops) +{ + struct target_backend *tb, *old; + + tb = kzalloc(sizeof(*tb), GFP_KERNEL); + if (!tb) + return -ENOMEM; + tb->ops = ops; + + mutex_lock(&backend_mutex); + list_for_each_entry(old, &backend_list, list) { + if (!strcmp(old->ops->name, ops->name)) { + pr_err("backend %s already registered.\n", ops->name); + mutex_unlock(&backend_mutex); + kfree(tb); return -EEXIST; } } - list_add_tail(&sub_api->sub_api_list, &subsystem_list); - mutex_unlock(&subsystem_mutex); + target_setup_backend_cits(tb); + list_add_tail(&tb->list, &backend_list); + mutex_unlock(&backend_mutex); - pr_debug("TCM: Registered subsystem plugin: %s struct module:" - " %p\n", sub_api->name, sub_api->owner); + pr_debug("TCM: Registered subsystem plugin: %s struct module: %p\n", + ops->name, ops->owner); return 0; } -EXPORT_SYMBOL(transport_subsystem_register); +EXPORT_SYMBOL(transport_backend_register); -void transport_subsystem_release(struct se_subsystem_api *sub_api) +void target_backend_unregister(const struct target_backend_ops *ops) { - mutex_lock(&subsystem_mutex); - list_del(&sub_api->sub_api_list); - mutex_unlock(&subsystem_mutex); + struct target_backend *tb; + + mutex_lock(&backend_mutex); + list_for_each_entry(tb, &backend_list, list) { + if (tb->ops == ops) { + list_del(&tb->list); + mutex_unlock(&backend_mutex); + /* + * Wait for any outstanding backend driver ->rcu_head + * callbacks to complete post TBO->free_device() -> + * call_rcu(), before allowing backend driver module + * unload of target_backend_ops->owner to proceed. + */ + rcu_barrier(); + kfree(tb); + return; + } + } + mutex_unlock(&backend_mutex); } -EXPORT_SYMBOL(transport_subsystem_release); +EXPORT_SYMBOL(target_backend_unregister); -static struct se_subsystem_api *core_get_backend(const char *sub_name) +static struct target_backend *core_get_backend(const char *name) { - struct se_subsystem_api *s; + struct target_backend *tb; - mutex_lock(&subsystem_mutex); - list_for_each_entry(s, &subsystem_list, sub_api_list) { - if (!strcmp(s->name, sub_name)) + mutex_lock(&backend_mutex); + list_for_each_entry(tb, &backend_list, list) { + if (!strcmp(tb->ops->name, name)) goto found; } - mutex_unlock(&subsystem_mutex); + mutex_unlock(&backend_mutex); return NULL; found: - if (s->owner && !try_module_get(s->owner)) - s = NULL; - mutex_unlock(&subsystem_mutex); - return s; + if (tb->ops->owner && !try_module_get(tb->ops->owner)) + tb = NULL; + mutex_unlock(&backend_mutex); + return tb; } struct se_hba * @@ -116,13 +123,13 @@ core_alloc_hba(const char *plugin_name, u32 plugin_dep_id, u32 hba_flags) hba->hba_index = scsi_get_new_index(SCSI_INST_INDEX); hba->hba_flags |= hba_flags; - hba->transport = core_get_backend(plugin_name); - if (!hba->transport) { + hba->backend = core_get_backend(plugin_name); + if (!hba->backend) { ret = -EINVAL; goto out_free_hba; } - ret = hba->transport->attach_hba(hba, plugin_dep_id); + ret = hba->backend->ops->attach_hba(hba, plugin_dep_id); if (ret < 0) goto out_module_put; @@ -137,9 +144,8 @@ core_alloc_hba(const char *plugin_name, u32 plugin_dep_id, u32 hba_flags) return hba; out_module_put: - if (hba->transport->owner) - module_put(hba->transport->owner); - hba->transport = NULL; + module_put(hba->backend->ops->owner); + hba->backend = NULL; out_free_hba: kfree(hba); return ERR_PTR(ret); @@ -150,7 +156,7 @@ core_delete_hba(struct se_hba *hba) { WARN_ON(hba->dev_count); - hba->transport->detach_hba(hba); + hba->backend->ops->detach_hba(hba); spin_lock(&hba_lock); list_del(&hba->hba_node); @@ -159,10 +165,14 @@ core_delete_hba(struct se_hba *hba) pr_debug("CORE_HBA[%d] - Detached HBA from Generic Target" " Core\n", hba->hba_id); - if (hba->transport->owner) - module_put(hba->transport->owner); + module_put(hba->backend->ops->owner); - hba->transport = NULL; + hba->backend = NULL; kfree(hba); return 0; } + +bool target_sense_desc_format(struct se_device *dev) +{ + return (dev) ? dev->transport->get_blocks(dev) > U32_MAX : false; +} |