linux-stable/drivers/target/target_core_hba.c
Thomas Gleixner 1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00

178 lines
4 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*******************************************************************************
* Filename: target_core_hba.c
*
* This file contains the TCM HBA Transport related functions.
*
* (c) Copyright 2003-2013 Datera, Inc.
*
* Nicholas A. Bellinger <nab@kernel.org>
*
******************************************************************************/
#include <linux/net.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/in.h>
#include <linux/module.h>
#include <net/sock.h>
#include <net/tcp.h>
#include <target/target_core_base.h>
#include <target/target_core_backend.h>
#include <target/target_core_fabric.h>
#include "target_core_internal.h"
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_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;
}
}
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",
ops->name, ops->owner);
return 0;
}
EXPORT_SYMBOL(transport_backend_register);
void target_backend_unregister(const struct target_backend_ops *ops)
{
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(target_backend_unregister);
static struct target_backend *core_get_backend(const char *name)
{
struct target_backend *tb;
mutex_lock(&backend_mutex);
list_for_each_entry(tb, &backend_list, list) {
if (!strcmp(tb->ops->name, name))
goto found;
}
mutex_unlock(&backend_mutex);
return NULL;
found:
if (tb->ops->owner && !try_module_get(tb->ops->owner))
tb = NULL;
mutex_unlock(&backend_mutex);
return tb;
}
struct se_hba *
core_alloc_hba(const char *plugin_name, u32 plugin_dep_id, u32 hba_flags)
{
struct se_hba *hba;
int ret = 0;
hba = kzalloc(sizeof(*hba), GFP_KERNEL);
if (!hba) {
pr_err("Unable to allocate struct se_hba\n");
return ERR_PTR(-ENOMEM);
}
spin_lock_init(&hba->device_lock);
mutex_init(&hba->hba_access_mutex);
hba->hba_index = scsi_get_new_index(SCSI_INST_INDEX);
hba->hba_flags |= hba_flags;
hba->backend = core_get_backend(plugin_name);
if (!hba->backend) {
ret = -EINVAL;
goto out_free_hba;
}
ret = hba->backend->ops->attach_hba(hba, plugin_dep_id);
if (ret < 0)
goto out_module_put;
spin_lock(&hba_lock);
hba->hba_id = hba_id_counter++;
list_add_tail(&hba->hba_node, &hba_list);
spin_unlock(&hba_lock);
pr_debug("CORE_HBA[%d] - Attached HBA to Generic Target"
" Core\n", hba->hba_id);
return hba;
out_module_put:
module_put(hba->backend->ops->owner);
hba->backend = NULL;
out_free_hba:
kfree(hba);
return ERR_PTR(ret);
}
int
core_delete_hba(struct se_hba *hba)
{
WARN_ON(hba->dev_count);
hba->backend->ops->detach_hba(hba);
spin_lock(&hba_lock);
list_del(&hba->hba_node);
spin_unlock(&hba_lock);
pr_debug("CORE_HBA[%d] - Detached HBA from Generic Target"
" Core\n", hba->hba_id);
module_put(hba->backend->ops->owner);
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;
}