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/*
* 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.
* Copyright (c) 2013-2014 Mellanox Technologies. 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 <linux/module.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"
MODULE_DESCRIPTION("iSER (iSCSI Extensions for RDMA) Datamover");
MODULE_LICENSE("Dual BSD/GPL");
MODULE_AUTHOR("Alex Nezhinsky, Dan Bar Dov, Or Gerlitz");
MODULE_VERSION(DRV_VER);
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 struct workqueue_struct *release_wq;
struct iser_global ig;
int iser_debug_level = 0;
module_param_named(debug_level, iser_debug_level, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0 (default:disabled)");
static unsigned int iscsi_max_lun = 512;
module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
MODULE_PARM_DESC(max_lun, "Max LUNs to allow per session (default:512");
unsigned int iser_max_sectors = ISER_DEF_MAX_SECTORS;
module_param_named(max_sectors, iser_max_sectors, uint, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(max_sectors, "Max number of sectors in a single scsi command (default:1024");
bool iser_always_reg = true;
module_param_named(always_register, iser_always_reg, bool, S_IRUGO);
MODULE_PARM_DESC(always_register,
"Always register memory, even for continuous memory regions (default:true)");
bool iser_pi_enable = false;
module_param_named(pi_enable, iser_pi_enable, bool, S_IRUGO);
MODULE_PARM_DESC(pi_enable, "Enable T10-PI offload support (default:disabled)");
int iser_pi_guard;
module_param_named(pi_guard, iser_pi_guard, int, S_IRUGO);
MODULE_PARM_DESC(pi_guard, "T10-PI guard_type [deprecated]");
/*
* iscsi_iser_recv() - Process a successful recv completion
* @conn: iscsi connection
* @hdr: iscsi header
* @rx_data: buffer containing receive data payload
* @rx_data_len: length of rx_data
*
* Notes: In case of data length errors or iscsi PDU completion failures
* this routine will signal iscsi layer of connection failure.
*/
void
iscsi_iser_recv(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
char *rx_data, int rx_data_len)
{
int rc = 0;
int datalen;
/* verify PDU length */
datalen = ntoh24(hdr->dlength);
if (datalen > rx_data_len || (datalen + 4) < rx_data_len) {
iser_err("wrong datalen %d (hdr), %d (IB)\n",
datalen, rx_data_len);
rc = ISCSI_ERR_DATALEN;
goto error;
}
if (datalen != rx_data_len)
iser_dbg("aligned datalen (%d) hdr, %d (IB)\n",
datalen, rx_data_len);
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);
}
/**
* iscsi_iser_pdu_alloc() - allocate an iscsi-iser PDU
* @task: iscsi task
* @opcode: iscsi command opcode
*
* Netes: This routine can't fail, just assign iscsi task
* hdr and max hdr size.
*/
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;
}
/**
* iser_initialize_task_headers() - Initialize task headers
* @task: iscsi task
* @tx_desc: iser tx descriptor
*
* Notes:
* This routine may race with iser teardown flow for scsi
* error handling TMFs. So for TMF we should acquire the
* state mutex to avoid dereferencing the IB device which
* may have already been terminated.
*/
int
iser_initialize_task_headers(struct iscsi_task *task,
struct iser_tx_desc *tx_desc)
{
struct 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;
const bool mgmt_task = !task->sc && !in_interrupt();
int ret = 0;
if (unlikely(mgmt_task))
mutex_lock(&iser_conn->state_mutex);
if (unlikely(iser_conn->state != ISER_CONN_UP)) {
ret = -ENODEV;
goto out;
}
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)) {
ret = -ENOMEM;
goto out;
}
tx_desc->wr_idx = 0;
tx_desc->mapped = true;
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->pd->local_dma_lkey;
iser_task->iser_conn = iser_conn;
out:
if (unlikely(mgmt_task))
mutex_unlock(&iser_conn->state_mutex);
return ret;
}
/**
* iscsi_iser_task_init() - Initialize iscsi-iser task
* @task: iscsi task
*
* Initialize the task for the scsi command or mgmt command.
*
* Return: Returns zero on success or -ENOMEM when failing
* to init task headers (dma mapping error).
*/
static int
iscsi_iser_task_init(struct iscsi_task *task)
{
struct iscsi_iser_task *iser_task = task->dd_data;
int ret;
ret = iser_initialize_task_headers(task, &iser_task->desc);
if (ret) {
iser_err("Failed to init task %p, err = %d\n",
iser_task, ret);
return ret;
}
/* mgmt task */
if (!task->sc)
return 0;
iser_task->command_sent = 0;
iser_task_rdma_init(iser_task);
iser_task->sc = task->sc;
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;
}
/**
* iscsi_iser_task_xmit() - xmit iscsi-iser task
* @task: iscsi task
*
* Return: zero on success or escalates $error on failure.
*/
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;
}
/**
* iscsi_iser_cleanup_task() - cleanup an iscsi-iser task
* @task: iscsi task
*
* Notes: In case the RDMA device is already NULL (might have
* been removed in DEVICE_REMOVAL CM event it will bail-out
* without doing dma unmapping.
*/
static void iscsi_iser_cleanup_task(struct iscsi_task *task)
{
struct iscsi_iser_task *iser_task = task->dd_data;
struct iser_tx_desc *tx_desc = &iser_task->desc;
struct iser_conn *iser_conn = task->conn->dd_data;
struct iser_device *device = iser_conn->ib_conn.device;
/* DEVICE_REMOVAL event might have already released the device */
if (!device)
return;
if (likely(tx_desc->mapped)) {
ib_dma_unmap_single(device->ib_device, tx_desc->dma_addr,
ISER_HEADERS_LEN, DMA_TO_DEVICE);
tx_desc->mapped = false;
}
/* 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);
}
}
/**
* iscsi_iser_check_protection() - check protection information status of task.
* @task: iscsi task
* @sector: error sector if exsists (output)
*
* Return: zero if no data-integrity errors have occured
* 0x1: data-integrity error occured in the guard-block
* 0x2: data-integrity error occured in the reference tag
* 0x3: data-integrity error occured in the application tag
*
* In addition the error sector is marked.
*/
static u8
iscsi_iser_check_protection(struct iscsi_task *task, sector_t *sector)
{
struct iscsi_iser_task *iser_task = task->dd_data;
if (iser_task->dir[ISER_DIR_IN])
return iser_check_task_pi_status(iser_task, ISER_DIR_IN,
sector);
else
return iser_check_task_pi_status(iser_task, ISER_DIR_OUT,
sector);
}
/**
* iscsi_iser_conn_create() - create a new iscsi-iser connection
* @cls_session: iscsi class connection
* @conn_idx: connection index within the session (for MCS)
*
* Return: iscsi_cls_conn when iscsi_conn_setup succeeds or NULL
* otherwise.
*/
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;
cls_conn = iscsi_conn_setup(cls_session, 0, 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;
return cls_conn;
}
/**
* iscsi_iser_conn_bind() - bind iscsi and iser connection structures
* @cls_session: iscsi class session
* @cls_conn: iscsi class connection
* @transport_eph: transport end-point handle
* @is_leading: indicate if this is the session leading connection (MCS)
*
* Return: zero on success, $error if iscsi_conn_bind fails and
* -EINVAL in case end-point doesn't exsits anymore or iser connection
* state is not UP (teardown already started).
*/
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 iser_conn *iser_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;
}
iser_conn = ep->dd_data;
mutex_lock(&iser_conn->state_mutex);
if (iser_conn->state != ISER_CONN_UP) {
error = -EINVAL;
iser_err("iser_conn %p state is %d, teardown started\n",
iser_conn, iser_conn->state);
goto out;
}
error = iser_alloc_rx_descriptors(iser_conn, conn->session);
if (error)
goto out;
/* binds the iSER connection retrieved from the previously
* connected ep_handle to the iSCSI layer connection. exchanges
* connection pointers */
iser_info("binding iscsi conn %p to iser_conn %p\n", conn, iser_conn);
conn->dd_data = iser_conn;
iser_conn->iscsi_conn = conn;
out:
mutex_unlock(&iser_conn->state_mutex);
return error;
}
/**
* iscsi_iser_conn_start() - start iscsi-iser connection
* @cls_conn: iscsi class connection
*
* Notes: Here iser intialize (or re-initialize) stop_completion as
* from this point iscsi must call conn_stop in session/connection
* teardown so iser transport must wait for it.
*/
static int
iscsi_iser_conn_start(struct iscsi_cls_conn *cls_conn)
{
struct iscsi_conn *iscsi_conn;
struct iser_conn *iser_conn;
iscsi_conn = cls_conn->dd_data;
iser_conn = iscsi_conn->dd_data;
reinit_completion(&iser_conn->stop_completion);
return iscsi_conn_start(cls_conn);
}
/**
* iscsi_iser_conn_stop() - stop iscsi-iser connection
* @cls_conn: iscsi class connection
* @flag: indicate if recover or terminate (passed as is)
*
* Notes: Calling iscsi_conn_stop might theoretically race with
* DEVICE_REMOVAL event and dereference a previously freed RDMA device
* handle, so we call it under iser the state lock to protect against
* this kind of race.
*/
static void
iscsi_iser_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iser_conn *iser_conn = conn->dd_data;
iser_info("stopping iscsi_conn: %p, iser_conn: %p\n", conn, iser_conn);
/*
* Userspace may have goofed up and not bound the connection or
* might have only partially setup the connection.
*/
if (iser_conn) {
mutex_lock(&iser_conn->state_mutex);
iser_conn_terminate(iser_conn);
iscsi_conn_stop(cls_conn, flag);
/* unbind */
iser_conn->iscsi_conn = NULL;
conn->dd_data = NULL;
complete(&iser_conn->stop_completion);
mutex_unlock(&iser_conn->state_mutex);
} else {
iscsi_conn_stop(cls_conn, flag);
}
}
/**
* iscsi_iser_session_destroy() - destroy iscsi-iser session
* @cls_session: iscsi class session
*
* Removes and free iscsi host.
*/
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 inline unsigned int
iser_dif_prot_caps(int prot_caps)
{
return ((prot_caps & IB_PROT_T10DIF_TYPE_1) ?
SHOST_DIF_TYPE1_PROTECTION | SHOST_DIX_TYPE0_PROTECTION |
SHOST_DIX_TYPE1_PROTECTION : 0) |
((prot_caps & IB_PROT_T10DIF_TYPE_2) ?
SHOST_DIF_TYPE2_PROTECTION | SHOST_DIX_TYPE2_PROTECTION : 0) |
((prot_caps & IB_PROT_T10DIF_TYPE_3) ?
SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE3_PROTECTION : 0);
}
/**
* iscsi_iser_session_create() - create an iscsi-iser session
* @ep: iscsi end-point handle
* @cmds_max: maximum commands in this session
* @qdepth: session command queue depth
* @initial_cmdsn: initiator command sequnce number
*
* Allocates and adds a scsi host, expose DIF supprot if
* exists, and sets up an iscsi session.
*/
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 *iser_conn = NULL;
struct ib_conn *ib_conn;
u32 max_fr_sectors;
u16 max_cmds;
shost = iscsi_host_alloc(&iscsi_iser_sht, 0, 0);
if (!shost)
return NULL;
shost->transportt = iscsi_iser_scsi_transport;
shost->cmd_per_lun = qdepth;
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) {
iser_conn = ep->dd_data;
max_cmds = iser_conn->max_cmds;
shost->sg_tablesize = iser_conn->scsi_sg_tablesize;
mutex_lock(&iser_conn->state_mutex);
if (iser_conn->state != ISER_CONN_UP) {
iser_err("iser conn %p already started teardown\n",
iser_conn);
mutex_unlock(&iser_conn->state_mutex);
goto free_host;
}
ib_conn = &iser_conn->ib_conn;
if (ib_conn->pi_support) {
u32 sig_caps = ib_conn->device->ib_device->attrs.sig_prot_cap;
scsi_host_set_prot(shost, iser_dif_prot_caps(sig_caps));
scsi_host_set_guard(shost, SHOST_DIX_GUARD_IP |
SHOST_DIX_GUARD_CRC);
}
if (iscsi_host_add(shost,
ib_conn->device->ib_device->dma_device)) {
mutex_unlock(&iser_conn->state_mutex);
goto free_host;
}
mutex_unlock(&iser_conn->state_mutex);
} else {
max_cmds = ISER_DEF_XMIT_CMDS_MAX;
if (iscsi_host_add(shost, NULL))
goto free_host;
}
/*
* FRs or FMRs can only map up to a (device) page per entry, but if the
* first entry is misaligned we'll end up using using two entries
* (head and tail) for a single page worth data, so we have to drop
* one segment from the calculation.
*/
max_fr_sectors = ((shost->sg_tablesize - 1) * PAGE_SIZE) >> 9;
shost->max_sectors = min(iser_max_sectors, max_fr_sectors);
if (cmds_max > max_cmds) {
iser_info("cmds_max changed from %u to %u\n",
cmds_max, max_cmds);
cmds_max = max_cmds;
}
cls_session = iscsi_session_setup(&iscsi_iser_transport, shost,
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) {
iser_err("DataDigest wasn't negotiated to None\n");
return -EPROTO;
}
break;
case ISCSI_PARAM_DATADGST_EN:
sscanf(buf, "%d", &value);
if (value) {
iser_err("DataDigest wasn't negotiated to None\n");
return -EPROTO;
}
break;
case ISCSI_PARAM_IFMARKER_EN:
sscanf(buf, "%d", &value);
if (value) {
iser_err("IFMarker wasn't negotiated to No\n");
return -EPROTO;
}
break;
case ISCSI_PARAM_OFMARKER_EN:
sscanf(buf, "%d", &value);
if (value) {
iser_err("OFMarker wasn't negotiated to No\n");
return -EPROTO;
}
break;
default:
return iscsi_set_param(cls_conn, param, buf, buflen);
}
return 0;
}
/**
* iscsi_iser_set_param() - set class connection parameter
* @cls_conn: iscsi class connection
* @stats: iscsi stats to output
*
* Output connection statistics.
*/
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 = 0;
}
static int iscsi_iser_get_ep_param(struct iscsi_endpoint *ep,
enum iscsi_param param, char *buf)
{
struct iser_conn *iser_conn = ep->dd_data;
int len;
switch (param) {
case ISCSI_PARAM_CONN_PORT:
case ISCSI_PARAM_CONN_ADDRESS:
if (!iser_conn || !iser_conn->ib_conn.cma_id)
return -ENOTCONN;
return iscsi_conn_get_addr_param((struct sockaddr_storage *)
&iser_conn->ib_conn.cma_id->route.addr.dst_addr,
param, buf);
break;
default:
return -ENOSYS;
}
return len;
}
/**
* iscsi_iser_ep_connect() - Initiate iSER connection establishment
* @shost: scsi_host
* @dst_addr: destination address
* @non-blocking: indicate if routine can block
*
* Allocate an iscsi endpoint, an iser_conn structure and bind them.
* After that start RDMA connection establishment via rdma_cm. We
* don't allocate iser_conn embedded in iscsi_endpoint since in teardown
* the endpoint will be destroyed at ep_disconnect while iser_conn will
* cleanup its resources asynchronuously.
*
* Return: iscsi_endpoint created by iscsi layer or ERR_PTR(error)
* if fails.
*/
static struct iscsi_endpoint *
iscsi_iser_ep_connect(struct Scsi_Host *shost, struct sockaddr *dst_addr,
int non_blocking)
{
int err;
struct iser_conn *iser_conn;
struct iscsi_endpoint *ep;
ep = iscsi_create_endpoint(0);
if (!ep)
return ERR_PTR(-ENOMEM);
iser_conn = kzalloc(sizeof(*iser_conn), GFP_KERNEL);
if (!iser_conn) {
err = -ENOMEM;
goto failure;
}
ep->dd_data = iser_conn;
iser_conn->ep = ep;
iser_conn_init(iser_conn);
err = iser_connect(iser_conn, NULL, dst_addr, non_blocking);
if (err)
goto failure;
return ep;
failure:
iscsi_destroy_endpoint(ep);
return ERR_PTR(err);
}
/**
* iscsi_iser_ep_poll() - poll for iser connection establishment to complete
* @ep: iscsi endpoint (created at ep_connect)
* @timeout_ms: polling timeout allowed in ms.
*
* This routine boils down to waiting for up_completion signaling
* that cma_id got CONNECTED event.
*
* Return: 1 if succeeded in connection establishment, 0 if timeout expired
* (libiscsi will retry will kick in) or -1 if interrupted by signal
* or more likely iser connection state transitioned to TEMINATING or
* DOWN during the wait period.
*/
static int
iscsi_iser_ep_poll(struct iscsi_endpoint *ep, int timeout_ms)
{
struct iser_conn *iser_conn = ep->dd_data;
int rc;
rc = wait_for_completion_interruptible_timeout(&iser_conn->up_completion,
msecs_to_jiffies(timeout_ms));
/* if conn establishment failed, return error code to iscsi */
if (rc == 0) {
mutex_lock(&iser_conn->state_mutex);
if (iser_conn->state == ISER_CONN_TERMINATING ||
iser_conn->state == ISER_CONN_DOWN)
rc = -1;
mutex_unlock(&iser_conn->state_mutex);
}
iser_info("iser conn %p rc = %d\n", iser_conn, rc);
if (rc > 0)
return 1; /* success, this is the equivalent of POLLOUT */
else if (!rc)
return 0; /* timeout */
else
return rc; /* signal */
}
/**
* iscsi_iser_ep_disconnect() - Initiate connection teardown process
* @ep: iscsi endpoint handle
*
* This routine is not blocked by iser and RDMA termination process
* completion as we queue a deffered work for iser/RDMA destruction
* and cleanup or actually call it immediately in case we didn't pass
* iscsi conn bind/start stage, thus it is safe.
*/
static void
iscsi_iser_ep_disconnect(struct iscsi_endpoint *ep)
{
struct iser_conn *iser_conn = ep->dd_data;
iser_info("ep %p iser conn %p\n", ep, iser_conn);
mutex_lock(&iser_conn->state_mutex);
iser_conn_terminate(iser_conn);
/*
* if iser_conn and iscsi_conn are bound, we must wait for
* iscsi_conn_stop and flush errors completion before freeing
* the iser resources. Otherwise we are safe to free resources
* immediately.
*/
if (iser_conn->iscsi_conn) {
INIT_WORK(&iser_conn->release_work, iser_release_work);
queue_work(release_wq, &iser_conn->release_work);
mutex_unlock(&iser_conn->state_mutex);
} else {
iser_conn->state = ISER_CONN_DOWN;
mutex_unlock(&iser_conn->state_mutex);
iser_conn_release(iser_conn);
}
iscsi_destroy_endpoint(ep);
}
static umode_t iser_attr_is_visible(int param_type, int param)
{
switch (param_type) {
case ISCSI_HOST_PARAM:
switch (param) {
case ISCSI_HOST_PARAM_NETDEV_NAME:
case ISCSI_HOST_PARAM_HWADDRESS:
case ISCSI_HOST_PARAM_INITIATOR_NAME:
return S_IRUGO;
default:
return 0;
}
case ISCSI_PARAM:
switch (param) {
case ISCSI_PARAM_MAX_RECV_DLENGTH:
case ISCSI_PARAM_MAX_XMIT_DLENGTH:
case ISCSI_PARAM_HDRDGST_EN:
case ISCSI_PARAM_DATADGST_EN:
case ISCSI_PARAM_CONN_ADDRESS:
case ISCSI_PARAM_CONN_PORT:
case ISCSI_PARAM_EXP_STATSN:
case ISCSI_PARAM_PERSISTENT_ADDRESS:
case ISCSI_PARAM_PERSISTENT_PORT:
case ISCSI_PARAM_PING_TMO:
case ISCSI_PARAM_RECV_TMO:
case ISCSI_PARAM_INITIAL_R2T_EN:
case ISCSI_PARAM_MAX_R2T:
case ISCSI_PARAM_IMM_DATA_EN:
case ISCSI_PARAM_FIRST_BURST:
case ISCSI_PARAM_MAX_BURST:
case ISCSI_PARAM_PDU_INORDER_EN:
case ISCSI_PARAM_DATASEQ_INORDER_EN:
case ISCSI_PARAM_TARGET_NAME:
case ISCSI_PARAM_TPGT:
case ISCSI_PARAM_USERNAME:
case ISCSI_PARAM_PASSWORD:
case ISCSI_PARAM_USERNAME_IN:
case ISCSI_PARAM_PASSWORD_IN:
case ISCSI_PARAM_FAST_ABORT:
case ISCSI_PARAM_ABORT_TMO:
case ISCSI_PARAM_LU_RESET_TMO:
case ISCSI_PARAM_TGT_RESET_TMO:
case ISCSI_PARAM_IFACE_NAME:
case ISCSI_PARAM_INITIATOR_NAME:
case ISCSI_PARAM_DISCOVERY_SESS:
return S_IRUGO;
default:
return 0;
}
}
return 0;
}
static int iscsi_iser_slave_alloc(struct scsi_device *sdev)
{
struct iscsi_session *session;
struct iser_conn *iser_conn;
struct ib_device *ib_dev;
session = starget_to_session(scsi_target(sdev))->dd_data;
iser_conn = session->leadconn->dd_data;
ib_dev = iser_conn->ib_conn.device->ib_device;
if (!(ib_dev->attrs.device_cap_flags & IB_DEVICE_SG_GAPS_REG))
blk_queue_virt_boundary(sdev->request_queue, ~MASK_4K);
return 0;
}
static struct scsi_host_template iscsi_iser_sht = {
.module = THIS_MODULE,
.name = "iSCSI Initiator over iSER",
.queuecommand = iscsi_queuecommand,
.change_queue_depth = scsi_change_queue_depth,
.sg_tablesize = ISCSI_ISER_DEF_SG_TABLESIZE,
.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 = ENABLE_CLUSTERING,
.slave_alloc = iscsi_iser_slave_alloc,
.proc_name = "iscsi_iser",
.this_id = -1,
.track_queue_depth = 1,
};
static struct iscsi_transport iscsi_iser_transport = {
.owner = THIS_MODULE,
.name = "iser",
.caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_TEXT_NEGO,
/* 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_conn_teardown,
.attr_is_visible = iser_attr_is_visible,
.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_iser_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,
.check_protection = iscsi_iser_check_protection,
/* 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) {
iser_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);
release_wq = alloc_workqueue("release workqueue", 0, 0);
if (!release_wq) {
iser_err("failed to allocate release workqueue\n");
err = -ENOMEM;
goto err_alloc_wq;
}
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 err_reg;
}
return 0;
err_reg:
destroy_workqueue(release_wq);
err_alloc_wq:
kmem_cache_destroy(ig.desc_cache);
return err;
}
static void __exit iser_exit(void)
{
struct iser_conn *iser_conn, *n;
int connlist_empty;
iser_dbg("Removing iSER datamover...\n");
destroy_workqueue(release_wq);
mutex_lock(&ig.connlist_mutex);
connlist_empty = list_empty(&ig.connlist);
mutex_unlock(&ig.connlist_mutex);
if (!connlist_empty) {
iser_err("Error cleanup stage completed but we still have iser "
"connections, destroying them anyway\n");
list_for_each_entry_safe(iser_conn, n, &ig.connlist,
conn_list) {
iser_conn_release(iser_conn);
}
}
iscsi_unregister_transport(&iscsi_iser_transport);
kmem_cache_destroy(ig.desc_cache);
}
module_init(iser_init);
module_exit(iser_exit);