mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-14 06:35:12 +00:00
Code Issues Releases Wiki Activity
linux-stable/include/scsi/scsi_transport_iscsi.h
Mike Christie 30a6c65236 [SCSI] iscsi: fix up iscsi eh 
The current iscsi_tcp eh is not nicely setup for dm-multipath
and performs some extra task management functions when they
are not needed.

The attached patch:

- Fixes the TMF issues. If a session is rebuilt
then we do not send aborts.

- Fixes the problem where if the host reset fired, we would
return SUCCESS even though we had not really done anything
yet. This ends up causing problem with scsi_error.c's TUR.

- If someone has turned on the userspace nop daemon code to try
and detect network problems before the scsi command timeout
we can now drop and clean up the session before the scsi command
timesout and fires the eh speeding up the time it takes for a
command to go from one patch to another. For network problems
we fail the command with DID_BUS_BUSY so if failfast is set
scsi_decide_disposition fails the command up to dm for it to
try on another path.

- And we had to add some basic iscsi session block code. Previously
if we were trying to repair a session we would retrun a MLQUEUE code
in the queuecommand. This worked but it was not the most efficient
or pretty thing to do since it would take a while to relogin
to the target. For iscsi_tcp/open-iscsi a lot of the iscsi error handler
is in userspace the block code is pretty bare. We will be
adding to that for qla4xxx.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-04-14 14:05:09 -05:00

185 lines
6.2 KiB
C
Raw Blame History

/*
* iSCSI transport class definitions
*
* Copyright (C) IBM Corporation, 2004
* Copyright (C) Mike Christie, 2004 - 2005
* Copyright (C) Dmitry Yusupov, 2004 - 2005
* Copyright (C) Alex Aizman, 2004 - 2005
*
* 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.
*/
#ifndef SCSI_TRANSPORT_ISCSI_H
#define SCSI_TRANSPORT_ISCSI_H
#include <linux/device.h>
#include <scsi/iscsi_if.h>
struct scsi_transport_template;
struct Scsi_Host;
struct mempool_zone;
struct iscsi_cls_conn;
/**
* struct iscsi_transport - iSCSI Transport template
*
* @name: transport name
* @caps: iSCSI Data-Path capabilities
* @create_session: create new iSCSI session object
* @destroy_session: destroy existing iSCSI session object
* @create_conn: create new iSCSI connection
* @bind_conn: associate this connection with existing iSCSI session
* and specified transport descriptor
* @destroy_conn: destroy inactive iSCSI connection
* @set_param: set iSCSI Data-Path operational parameter
* @start_conn: set connection to be operational
* @stop_conn: suspend/recover/terminate connection
* @send_pdu: send iSCSI PDU, Login, Logout, NOP-Out, Reject, Text.
*
* Template API provided by iSCSI Transport
*/
struct iscsi_transport {
struct module *owner;
char *name;
unsigned int caps;
/* LLD sets this to indicate what values it can export to sysfs */
unsigned int param_mask;
struct scsi_host_template *host_template;
/* LLD session/scsi_host data size */
int hostdata_size;
/* LLD connection data size */
int conndata_size;
/* LLD session data size */
int sessiondata_size;
int max_lun;
unsigned int max_conn;
unsigned int max_cmd_len;
struct iscsi_cls_session *(*create_session)
(struct scsi_transport_template *t, uint32_t sn, uint32_t *hn);
void (*destroy_session) (struct iscsi_cls_session *session);
struct iscsi_cls_conn *(*create_conn) (struct iscsi_cls_session *sess,
uint32_t cid);
int (*bind_conn) (struct iscsi_cls_session *session,
struct iscsi_cls_conn *cls_conn,
uint32_t transport_fd, int is_leading);
int (*start_conn) (struct iscsi_cls_conn *conn);
void (*stop_conn) (struct iscsi_cls_conn *conn, int flag);
void (*destroy_conn) (struct iscsi_cls_conn *conn);
int (*set_param) (struct iscsi_cls_conn *conn, enum iscsi_param param,
uint32_t value);
int (*get_conn_param) (struct iscsi_cls_conn *conn,
enum iscsi_param param, uint32_t *value);
int (*get_session_param) (struct iscsi_cls_session *session,
enum iscsi_param param, uint32_t *value);
int (*get_conn_str_param) (struct iscsi_cls_conn *conn,
enum iscsi_param param, char *buf);
int (*get_session_str_param) (struct iscsi_cls_session *session,
enum iscsi_param param, char *buf);
int (*send_pdu) (struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
char *data, uint32_t data_size);
void (*get_stats) (struct iscsi_cls_conn *conn,
struct iscsi_stats *stats);
void (*session_recovery_timedout) (struct iscsi_cls_session *session);
};
/*
* transport registration upcalls
*/
extern struct scsi_transport_template *iscsi_register_transport(struct iscsi_transport *tt);
extern int iscsi_unregister_transport(struct iscsi_transport *tt);
/*
* control plane upcalls
*/
extern void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error);
extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
char *data, uint32_t data_size);
struct iscsi_cls_conn {
struct list_head conn_list; /* item in connlist */
void *dd_data; /* LLD private data */
struct iscsi_transport *transport;
uint32_t cid; /* connection id */
/* portal/group values we got during discovery */
char *persistent_address;
int persistent_port;
/* portal/group values we are currently using */
char *address;
int port;
int active; /* must be accessed with the connlock */
struct device dev; /* sysfs transport/container device */
struct mempool_zone *z_error;
struct mempool_zone *z_pdu;
struct list_head freequeue;
};
#define iscsi_dev_to_conn(_dev) \
container_of(_dev, struct iscsi_cls_conn, dev)
struct iscsi_cls_session {
struct list_head sess_list; /* item in session_list */
struct list_head host_list;
struct iscsi_transport *transport;
/* iSCSI values used as unique id by userspace. */
char *targetname;
int tpgt;
/* recovery fields */
int recovery_tmo;
struct work_struct recovery_work;
int target_id;
int channel;
int sid; /* session id */
void *dd_data; /* LLD private data */
struct device dev; /* sysfs transport/container device */
};
#define iscsi_dev_to_session(_dev) \
container_of(_dev, struct iscsi_cls_session, dev)
#define iscsi_session_to_shost(_session) \
dev_to_shost(_session->dev.parent)
struct iscsi_host {
int next_target_id;
struct list_head sessions;
struct mutex mutex;
};
/*
* session and connection functions that can be used by HW iSCSI LLDs
*/
extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost,
struct iscsi_transport *t, int channel);
extern int iscsi_destroy_session(struct iscsi_cls_session *session);
extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess,
uint32_t cid);
extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn);
extern void iscsi_unblock_session(struct iscsi_cls_session *session);
extern void iscsi_block_session(struct iscsi_cls_session *session);
/*
* session functions used by software iscsi
*/
extern struct Scsi_Host *
iscsi_transport_create_session(struct scsi_transport_template *scsit,
struct iscsi_transport *transport);
extern int iscsi_transport_destroy_session(struct Scsi_Host *shost);
#endif
Reference in a new issue View git blame Copy permalink