- 根目录:
- drivers
- infiniband
- ulp
- iser
- iscsi_iser.c
/*
* iSCSI Initiator over iSER Data-Path
*
* Copyright (C) 2004 Dmitry Yusupov
* Copyright (C) 2004 Alex Aizman
* Copyright (C) 2005 Mike Christie
* Copyright (c) 2005, 2006 Voltaire, Inc. All rights reserved.
* maintained by openib-general@openib.org
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
* Credits:
* Christoph Hellwig
* FUJITA Tomonori
* Arne Redlich
* Zhenyu Wang
* Modified by:
* Erez Zilber
*/
#include <linux/types.h>
#include <linux/list.h>
#include <linux/hardirq.h>
#include <linux/kfifo.h>
#include <linux/blkdev.h>
#include <linux/init.h>
#include <linux/ioctl.h>
#include <linux/cdev.h>
#include <linux/in.h>
#include <linux/net.h>
#include <linux/scatterlist.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <asm/uaccess.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi.h>
#include <scsi/scsi_transport_iscsi.h>
#include "iscsi_iser.h"
static struct scsi_host_template iscsi_iser_sht;
static struct iscsi_transport iscsi_iser_transport;
static struct scsi_transport_template *iscsi_iser_scsi_transport;
static unsigned int iscsi_max_lun = 512;
module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
int iser_debug_level = 0;
MODULE_DESCRIPTION("iSER (iSCSI Extensions for RDMA) Datamover "
"v" DRV_VER " (" DRV_DATE ")");
MODULE_LICENSE("Dual BSD/GPL");
MODULE_AUTHOR("Alex Nezhinsky, Dan Bar Dov, Or Gerlitz");
module_param_named(debug_level, iser_debug_level, int, 0644);
MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0 (default:disabled)");
struct iser_global ig;
void
iscsi_iser_recv(struct iscsi_conn *conn,
struct iscsi_hdr *hdr, char *rx_data, int rx_data_len)
{
int rc = 0;
int datalen;
int ahslen;
/* verify PDU length */
datalen = ntoh24(hdr->dlength);
if (datalen != rx_data_len) {
printk(KERN_ERR "iscsi_iser: datalen %d (hdr) != %d (IB) \n",
datalen, rx_data_len);
rc = ISCSI_ERR_DATALEN;
goto error;
}
/* read AHS */
ahslen = hdr->hlength * 4;
rc = iscsi_complete_pdu(conn, hdr, rx_data, rx_data_len);
if (rc && rc != ISCSI_ERR_NO_SCSI_CMD)
goto error;
return;
error:
iscsi_conn_failure(conn, rc);
}
static int iscsi_iser_pdu_alloc(struct iscsi_task *task, uint8_t opcode)
{
struct iscsi_iser_task *iser_task = task->dd_data;
task->hdr = (struct iscsi_hdr *)&iser_task->desc.iscsi_header;
task->hdr_max = sizeof(iser_task->desc.iscsi_header);
return 0;
}
int iser_initialize_task_headers(struct iscsi_task *task,
struct iser_tx_desc *tx_desc)
{
struct iscsi_iser_conn *iser_conn = task->conn->dd_data;
struct iser_device *device = iser_conn->ib_conn->device;
struct iscsi_iser_task *iser_task = task->dd_data;
u64 dma_addr;
dma_addr = ib_dma_map_single(device->ib_device, (void *)tx_desc,
ISER_HEADERS_LEN, DMA_TO_DEVICE);
if (ib_dma_mapping_error(device->ib_device, dma_addr))
return -ENOMEM;
tx_desc->dma_addr = dma_addr;
tx_desc->tx_sg[0].addr = tx_desc->dma_addr;
tx_desc->tx_sg[0].length = ISER_HEADERS_LEN;
tx_desc->tx_sg[0].lkey = device->mr->lkey;
iser_task->headers_initialized = 1;
iser_task->iser_conn = iser_conn;
return 0;
}
/**
* iscsi_iser_task_init - Initialize task
* @task: iscsi task
*
* Initialize the task for the scsi command or mgmt command.
*/
static int
iscsi_iser_task_init(struct iscsi_task *task)
{
struct iscsi_iser_task *iser_task = task->dd_data;
if (!iser_task->headers_initialized)
if (iser_initialize_task_headers(task, &iser_task->desc))
return -ENOMEM;
/* mgmt task */
if (!task->sc)
return 0;
iser_task->command_sent = 0;
iser_task_rdma_init(iser_task);
return 0;
}
/**
* iscsi_iser_mtask_xmit - xmit management(immediate) task
* @conn: iscsi connection
* @task: task management task
*
* Notes:
* The function can return -EAGAIN in which case caller must
* call it again later, or recover. '0' return code means successful
* xmit.
*
**/
static int
iscsi_iser_mtask_xmit(struct iscsi_conn *conn, struct iscsi_task *task)
{
int error = 0;
iser_dbg("mtask xmit [cid %d itt 0x%x]\n", conn->id, task->itt);
error = iser_send_control(conn, task);
/* since iser xmits control with zero copy, tasks can not be recycled
* right after sending them.
* The recycling scheme is based on whether a response is expected
* - if yes, the task is recycled at iscsi_complete_pdu
* - if no, the task is recycled at iser_snd_completion
*/
return error;
}
static int
iscsi_iser_task_xmit_unsol_data(struct iscsi_conn *conn,
struct iscsi_task *task)
{
struct iscsi_r2t_info *r2t = &task->unsol_r2t;
struct iscsi_data hdr;
int error = 0;
/* Send data-out PDUs while there's still unsolicited data to send */
while (iscsi_task_has_unsol_data(task)) {
iscsi_prep_data_out_pdu(task, r2t, &hdr);
iser_dbg("Sending data-out: itt 0x%x, data count %d\n",
hdr.itt, r2t->data_count);
/* the buffer description has been passed with the command */
/* Send the command */
error = iser_send_data_out(conn, task, &hdr);
if (error) {
r2t->datasn--;
goto iscsi_iser_task_xmit_unsol_data_exit;
}
r2t->sent += r2t->data_count;
iser_dbg("Need to send %d more as data-out PDUs\n",
r2t->data_length - r2t->sent);
}
iscsi_iser_task_xmit_unsol_data_exit:
return error;
}
static int
iscsi_iser_task_xmit(struct iscsi_task *task)
{
struct iscsi_conn *conn = task->conn;
struct iscsi_iser_task *iser_task = task->dd_data;
int error = 0;
if (!task->sc)
return iscsi_iser_mtask_xmit(conn, task);
if (task->sc->sc_data_direction == DMA_TO_DEVICE) {
BUG_ON(scsi_bufflen(task->sc) == 0);
iser_dbg("cmd [itt %x total %d imm %d unsol_data %d\n",
task->itt, scsi_bufflen(task->sc),
task->imm_count, task->unsol_r2t.data_length);
}
iser_dbg("ctask xmit [cid %d itt 0x%x]\n",
conn->id, task->itt);
/* Send the cmd PDU */
if (!iser_task->command_sent) {
error = iser_send_command(conn, task);
if (error)
goto iscsi_iser_task_xmit_exit;
iser_task->command_sent = 1;
}
/* Send unsolicited data-out PDU(s) if necessary */
if (iscsi_task_has_unsol_data(task))
error = iscsi_iser_task_xmit_unsol_data(conn, task);
iscsi_iser_task_xmit_exit:
return error;
}
static void iscsi_iser_cleanup_task(struct iscsi_task *task)
{
struct iscsi_iser_task *iser_task = task->dd_data;
/* mgmt tasks do not need special cleanup */
if (!task->sc)
return;
if (iser_task->status == ISER_TASK_STATUS_STARTED) {
iser_task->status = ISER_TASK_STATUS_COMPLETED;
iser_task_rdma_finalize(iser_task);
}
}
static struct iscsi_cls_conn *
iscsi_iser_conn_create(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
{
struct iscsi_conn *conn;
struct iscsi_cls_conn *cls_conn;
struct iscsi_iser_conn *iser_conn;
cls_conn = iscsi_conn_setup(cls_session, sizeof(*iser_conn), conn_idx);
if (!cls_conn)
return NULL;
conn = cls_conn->dd_data;
/*
* due to issues with the login code re iser sematics
* this not set in iscsi_conn_setup - FIXME
*/
conn->max_recv_dlength = ISER_RECV_DATA_SEG_LEN;
iser_conn = conn->dd_data;
conn->dd_data = iser_conn;
iser_conn->iscsi_conn = conn;
return cls_conn;
}
static void
iscsi_iser_conn_destroy(struct iscsi_cls_conn *cls_conn)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_iser_conn *iser_conn = conn->dd_data;
struct iser_conn *ib_conn = iser_conn->ib_conn;
iscsi_conn_teardown(cls_conn);
/*
* Userspace will normally call the stop callback and
* already have freed the ib_conn, but if it goofed up then
* we free it here.
*/
if (ib_conn) {
ib_conn->iser_conn = NULL;
iser_conn_put(ib_conn, 1); /* deref iscsi/ib conn unbinding */
}
}
static int
iscsi_iser_conn_bind(struct iscsi_cls_session *cls_session,
struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
int is_leading)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_iser_conn *iser_conn;
struct iser_conn *ib_conn;
struct iscsi_endpoint *ep;
int error;
error = iscsi_conn_bind(cls_session, cls_conn, is_leading);
if (error)
return error;
/* the transport ep handle comes from user space so it must be
* verified against the global ib connections list */
ep = iscsi_lookup_endpoint(transport_eph);
if (!ep) {
iser_err("can't bind eph %llx\n",
(unsigned long long)transport_eph);
return -EINVAL;
}
ib_conn = ep->dd_data;
if (iser_alloc_rx_descriptors(ib_conn))
return -ENOMEM;
/* binds the iSER connection retrieved from the previously
* connected ep_handle to the iSCSI layer connection. exchanges
* connection pointers */
iser_err("binding iscsi/iser conn %p %p to ib_conn %p\n",
conn, conn->dd_data, ib_conn);
iser_conn = conn->dd_data;
ib_conn->iser_conn = iser_conn;
iser_conn->ib_conn = ib_conn;
iser_conn_get(ib_conn); /* ref iscsi/ib conn binding */
return 0;
}
static void
iscsi_iser_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_iser_conn *iser_conn = conn->dd_data;
struct iser_conn *ib_conn = iser_conn->ib_conn;
/*
* Userspace may have goofed up and not bound the connection or
* might have only partially setup the connection.
*/
if (ib_conn) {
iscsi_conn_stop(cls_conn, flag);
/*
* There is no unbind event so the stop callback
* must release the ref from the bind.
*/
iser_conn_put(ib_conn, 1); /* deref iscsi/ib conn unbinding */
}
iser_conn->ib_conn = NULL;
}
static void iscsi_iser_session_destroy(struct iscsi_cls_session *cls_session)
{
struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
iscsi_session_teardown(cls_session);
iscsi_host_remove(shost);
iscsi_host_free(shost);
}
static struct iscsi_cls_session *
iscsi_iser_session_create(struct iscsi_endpoint *ep,
uint16_t cmds_max, uint16_t qdepth,
uint32_t initial_cmdsn)
{
struct iscsi_cls_session *cls_session;
struct iscsi_session *session;
struct Scsi_Host *shost;
struct iser_conn *ib_conn;
shost = iscsi_host_alloc(&iscsi_iser_sht, 0, 0);
if (!shost)
return NULL;
shost->transportt = iscsi_iser_scsi_transport;
shost->max_lun = iscsi_max_lun;
shost->max_id = 0;
shost->max_channel = 0;
shost->max_cmd_len = 16;
/*
* older userspace tools (before 2.0-870) did not pass us
* the leading conn's ep so this will be NULL;
*/
if (ep)
ib_conn = ep->dd_data;
if (iscsi_host_add(shost,
ep ? ib_conn->device->ib_device->dma_device : NULL))
goto free_host;
/*
* we do not support setting can_queue cmd_per_lun from userspace yet
* because we preallocate so many resources
*/
cls_session = iscsi_session_setup(&iscsi_iser_transport, shost,
ISCSI_DEF_XMIT_CMDS_MAX, 0,
sizeof(struct iscsi_iser_task),
initial_cmdsn, 0);
if (!cls_session)
goto remove_host;
session = cls_session->dd_data;
shost->can_queue = session->scsi_cmds_max;
return cls_session;
remove_host:
iscsi_host_remove(shost);
free_host:
iscsi_host_free(shost);
return NULL;
}
static int
iscsi_iser_set_param(struct iscsi_cls_conn *cls_conn,
enum iscsi_param param, char *buf, int buflen)
{
int value;
switch (param) {
case ISCSI_PARAM_MAX_RECV_DLENGTH:
/* TBD */
break;
case ISCSI_PARAM_HDRDGST_EN:
sscanf(buf, "%d", &value);
if (value) {
printk(KERN_ERR "DataDigest wasn't negotiated to None");
return -EPROTO;
}
break;
case ISCSI_PARAM_DATADGST_EN:
sscanf(buf, "%d", &value);
if (value) {
printk(KERN_ERR "DataDigest wasn't negotiated to None");
return -EPROTO;
}
break;
case ISCSI_PARAM_IFMARKER_EN:
sscanf(buf, "%d", &value);
if (value) {
printk(KERN_ERR "IFMarker wasn't negotiated to No");
return -EPROTO;
}
break;
case ISCSI_PARAM_OFMARKER_EN:
sscanf(buf, "%d", &value);
if (value) {
printk(KERN_ERR "OFMarker wasn't negotiated to No");
return -EPROTO;
}
break;
default:
return iscsi_set_param(cls_conn, param, buf, buflen);
}
return 0;
}
static void
iscsi_iser_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
{
struct iscsi_conn *conn = cls_conn->dd_data;
stats->txdata_octets = conn->txdata_octets;
stats->rxdata_octets = conn->rxdata_octets;
stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
stats->dataout_pdus = conn->dataout_pdus_cnt;
stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
stats->datain_pdus = conn->datain_pdus_cnt; /* always 0 */
stats->r2t_pdus = conn->r2t_pdus_cnt; /* always 0 */
stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
stats->custom_length = 4;
strcpy(stats->custom[0].desc, "qp_tx_queue_full");
stats->custom[0].value = 0; /* TB iser_conn->qp_tx_queue_full; */
strcpy(stats->custom[1].desc, "fmr_map_not_avail");
stats->custom[1].value = 0; /* TB iser_conn->fmr_map_not_avail */;
strcpy(stats->custom[2].desc, "eh_abort_cnt");
stats->custom[2].value = conn->eh_abort_cnt;
strcpy(stats->custom[3].desc, "fmr_unalign_cnt");
stats->custom[3].value = conn->fmr_unalign_cnt;
}
static int iscsi_iser_get_ep_param(struct iscsi_endpoint *ep,
enum iscsi_param param, char *buf)
{
struct iser_conn *ib_conn = ep->dd_data;
int len;
switch (param) {
case ISCSI_PARAM_CONN_PORT:
case ISCSI_PARAM_CONN_ADDRESS:
if (!ib_conn || !ib_conn->cma_id)
return -ENOTCONN;
return iscsi_conn_get_addr_param((struct sockaddr_storage *)
&ib_conn->cma_id->route.addr.dst_addr,
param, buf);
break;
default:
return -ENOSYS;
}
return len;
}
static struct iscsi_endpoint *
iscsi_iser_ep_connect(struct Scsi_Host *shost, struct sockaddr *dst_addr,
int non_blocking)
{
int err;
struct iser_conn *ib_conn;
struct iscsi_endpoint *ep;
ep = iscsi_create_endpoint(sizeof(*ib_conn));
if (!ep)
return ERR_PTR(-ENOMEM);
ib_conn = ep->dd_data;
ib_conn->ep = ep;
iser_conn_init(ib_conn);
err = iser_connect(ib_conn, NULL, (struct sockaddr_in *)dst_addr,
non_blocking);
if (err) {
iscsi_destroy_endpoint(ep);
return ERR_PTR(err);
}
return ep;
}
static int
iscsi_iser_ep_poll(struct iscsi_endpoint *ep, int timeout_ms)
{
struct iser_conn *ib_conn;
int rc;
ib_conn = ep->dd_data;
rc = wait_event_interruptible_timeout(ib_conn->wait,
ib_conn->state == ISER_CONN_UP,
msecs_to_jiffies(timeout_ms));
/* if conn establishment failed, return error code to iscsi */
if (!rc &&
(ib_conn->state == ISER_CONN_TERMINATING ||
ib_conn->state == ISER_CONN_DOWN))
rc = -1;
iser_err("ib conn %p rc = %d\n", ib_conn, rc);
if (rc > 0)
return 1; /* success, this is the equivalent of POLLOUT */
else if (!rc)
return 0; /* timeout */
else
return rc; /* signal */
}
static void
iscsi_iser_ep_disconnect(struct iscsi_endpoint *ep)
{
struct iser_conn *ib_conn;
ib_conn = ep->dd_data;
if (ib_conn->iser_conn)
/*
* Must suspend xmit path if the ep is bound to the
* iscsi_conn, so we know we are not accessing the ib_conn
* when we free it.
*
* This may not be bound if the ep poll failed.
*/
iscsi_suspend_tx(ib_conn->iser_conn->iscsi_conn);
iser_err("ib conn %p state %d\n",ib_conn, ib_conn->state);
iser_conn_terminate(ib_conn);
}
static struct scsi_host_template iscsi_iser_sht = {
.module = THIS_MODULE,
.name = "iSCSI Initiator over iSER, v." DRV_VER,
.queuecommand = iscsi_queuecommand,
.change_queue_depth = iscsi_change_queue_depth,
.sg_tablesize = ISCSI_ISER_SG_TABLESIZE,
.max_sectors = 1024,
.cmd_per_lun = ISER_DEF_CMD_PER_LUN,
.eh_abort_handler = iscsi_eh_abort,
.eh_device_reset_handler= iscsi_eh_device_reset,
.eh_target_reset_handler = iscsi_eh_recover_target,
.target_alloc = iscsi_target_alloc,
.use_clustering = DISABLE_CLUSTERING,
.proc_name = "iscsi_iser",
.this_id = -1,
};
static struct iscsi_transport iscsi_iser_transport = {
.owner = THIS_MODULE,
.name = "iser",
.caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T,
.param_mask = ISCSI_MAX_RECV_DLENGTH |
ISCSI_MAX_XMIT_DLENGTH |
ISCSI_HDRDGST_EN |
ISCSI_DATADGST_EN |
ISCSI_INITIAL_R2T_EN |
ISCSI_MAX_R2T |
ISCSI_IMM_DATA_EN |
ISCSI_FIRST_BURST |
ISCSI_MAX_BURST |
ISCSI_PDU_INORDER_EN |
ISCSI_DATASEQ_INORDER_EN |
ISCSI_CONN_PORT |
ISCSI_CONN_ADDRESS |
ISCSI_EXP_STATSN |
ISCSI_PERSISTENT_PORT |
ISCSI_PERSISTENT_ADDRESS |
ISCSI_TARGET_NAME | ISCSI_TPGT |
ISCSI_USERNAME | ISCSI_PASSWORD |
ISCSI_USERNAME_IN | ISCSI_PASSWORD_IN |
ISCSI_FAST_ABORT | ISCSI_ABORT_TMO |
ISCSI_LU_RESET_TMO | ISCSI_TGT_RESET_TMO |
ISCSI_PING_TMO | ISCSI_RECV_TMO |
ISCSI_IFACE_NAME | ISCSI_INITIATOR_NAME,
.host_param_mask = ISCSI_HOST_HWADDRESS |
ISCSI_HOST_NETDEV_NAME |
ISCSI_HOST_INITIATOR_NAME,
/* session management */
.create_session = iscsi_iser_session_create,
.destroy_session = iscsi_iser_session_destroy,
/* connection management */
.create_conn = iscsi_iser_conn_create,
.bind_conn = iscsi_iser_conn_bind,
.destroy_conn = iscsi_iser_conn_destroy,
.set_param = iscsi_iser_set_param,
.get_conn_param = iscsi_conn_get_param,
.get_ep_param = iscsi_iser_get_ep_param,
.get_session_param = iscsi_session_get_param,
.start_conn = iscsi_conn_start,
.stop_conn = iscsi_iser_conn_stop,
/* iscsi host params */
.get_host_param = iscsi_host_get_param,
.set_host_param = iscsi_host_set_param,
/* IO */
.send_pdu = iscsi_conn_send_pdu,
.get_stats = iscsi_iser_conn_get_stats,
.init_task = iscsi_iser_task_init,
.xmit_task = iscsi_iser_task_xmit,
.cleanup_task = iscsi_iser_cleanup_task,
.alloc_pdu = iscsi_iser_pdu_alloc,
/* recovery */
.session_recovery_timedout = iscsi_session_recovery_timedout,
.ep_connect = iscsi_iser_ep_connect,
.ep_poll = iscsi_iser_ep_poll,
.ep_disconnect = iscsi_iser_ep_disconnect
};
static int __init iser_init(void)
{
int err;
iser_dbg("Starting iSER datamover...\n");
if (iscsi_max_lun < 1) {
printk(KERN_ERR "Invalid max_lun value of %u\n", iscsi_max_lun);
return -EINVAL;
}
memset(&ig, 0, sizeof(struct iser_global));
ig.desc_cache = kmem_cache_create("iser_descriptors",
sizeof(struct iser_tx_desc),
0, SLAB_HWCACHE_ALIGN,
NULL);
if (ig.desc_cache == NULL)
return -ENOMEM;
/* device init is called only after the first addr resolution */
mutex_init(&ig.device_list_mutex);
INIT_LIST_HEAD(&ig.device_list);
mutex_init(&ig.connlist_mutex);
INIT_LIST_HEAD(&ig.connlist);
iscsi_iser_scsi_transport = iscsi_register_transport(
&iscsi_iser_transport);
if (!iscsi_iser_scsi_transport) {
iser_err("iscsi_register_transport failed\n");
err = -EINVAL;
goto register_transport_failure;
}
return 0;
register_transport_failure:
kmem_cache_destroy(ig.desc_cache);
return err;
}
static void __exit iser_exit(void)
{
iser_dbg("Removing iSER datamover...\n");
iscsi_unregister_transport(&iscsi_iser_transport);
kmem_cache_destroy(ig.desc_cache);
}
module_init(iser_init);
module_exit(iser_exit);