linux/drivers/target/target_core_hba.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

174 lines
4.4 KiB
C

/*******************************************************************************
* Filename: target_core_hba.c
*
* This file contains the TCM HBA Transport related functions.
*
* Copyright (c) 2003, 2004, 2005 PyX Technologies, Inc.
* Copyright (c) 2005, 2006, 2007 SBE, Inc.
* Copyright (c) 2007-2010 Rising Tide Systems
* Copyright (c) 2008-2010 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/net.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/in.h>
#include <net/sock.h>
#include <net/tcp.h>
#include <target/target_core_base.h>
#include <target/target_core_device.h>
#include <target/target_core_tpg.h>
#include <target/target_core_transport.h>
#include "target_core_hba.h"
static LIST_HEAD(subsystem_list);
static DEFINE_MUTEX(subsystem_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);
return -EEXIST;
}
}
list_add_tail(&sub_api->sub_api_list, &subsystem_list);
mutex_unlock(&subsystem_mutex);
pr_debug("TCM: Registered subsystem plugin: %s struct module:"
" %p\n", sub_api->name, sub_api->owner);
return 0;
}
EXPORT_SYMBOL(transport_subsystem_register);
void transport_subsystem_release(struct se_subsystem_api *sub_api)
{
mutex_lock(&subsystem_mutex);
list_del(&sub_api->sub_api_list);
mutex_unlock(&subsystem_mutex);
}
EXPORT_SYMBOL(transport_subsystem_release);
static struct se_subsystem_api *core_get_backend(const char *sub_name)
{
struct se_subsystem_api *s;
mutex_lock(&subsystem_mutex);
list_for_each_entry(s, &subsystem_list, sub_api_list) {
if (!strcmp(s->name, sub_name))
goto found;
}
mutex_unlock(&subsystem_mutex);
return NULL;
found:
if (s->owner && !try_module_get(s->owner))
s = NULL;
mutex_unlock(&subsystem_mutex);
return s;
}
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);
}
INIT_LIST_HEAD(&hba->hba_dev_list);
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->transport = core_get_backend(plugin_name);
if (!hba->transport) {
ret = -EINVAL;
goto out_free_hba;
}
ret = hba->transport->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:
if (hba->transport->owner)
module_put(hba->transport->owner);
hba->transport = NULL;
out_free_hba:
kfree(hba);
return ERR_PTR(ret);
}
int
core_delete_hba(struct se_hba *hba)
{
if (!list_empty(&hba->hba_dev_list))
dump_stack();
hba->transport->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);
if (hba->transport->owner)
module_put(hba->transport->owner);
hba->transport = NULL;
kfree(hba);
return 0;
}