From e5fd91f1ef340da553f7a79da9540c3db711c937 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Tue, 8 Sep 2015 01:01:14 -0300 Subject: Linux-libre 4.2-gnu --- drivers/target/target_core_hba.c | 105 +++++++++++++++++++++++---------------- 1 file changed, 62 insertions(+), 43 deletions(-) (limited to 'drivers/target/target_core_hba.c') diff --git a/drivers/target/target_core_hba.c b/drivers/target/target_core_hba.c index ff95f95dc..be9cefc07 100644 --- a/drivers/target/target_core_hba.c +++ b/drivers/target/target_core_hba.c @@ -36,67 +36,86 @@ #include #include #include -#include #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 * @@ -117,13 +136,13 @@ 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; @@ -138,8 +157,8 @@ core_alloc_hba(const char *plugin_name, u32 plugin_dep_id, u32 hba_flags) return hba; out_module_put: - 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 +169,7 @@ 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); @@ -159,9 +178,9 @@ core_delete_hba(struct se_hba *hba) pr_debug("CORE_HBA[%d] - Detached HBA from Generic Target" " Core\n", hba->hba_id); - module_put(hba->transport->owner); + module_put(hba->backend->ops->owner); - hba->transport = NULL; + hba->backend = NULL; kfree(hba); return 0; } -- cgit v1.2.3-54-g00ecf