[SCSI] zfcp: Block FC transport rports early on errors

Use the I/O blocking mechanism in the FC transport class to allow
faster failovers for multipathing:
- Call fc_remote_port_delete early to set the rport to BLOCKED.
- Check the rport status in queuecommand with fc_remote_portchkready
  to no longer accept new I/O for this port and fail the I/O with the
  appropriate scsi_cmnd result.
- Implement the terminate_rport_io handler to abort all pending I/O
  requests
- Return SCSI commands with DID_TRANSPORT_DISRUPTED while erp is
  running.
- When updating the remote port status, check for late changes and
  update the remote ports status accordingly.

Acked-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This commit is contained in:
Christof Schmitt 2009-03-02 13:09:08 +01:00 committed by James Bottomley
parent 2409549068
commit a2fa0aede0
7 changed files with 157 additions and 56 deletions

View File

@ -3,7 +3,7 @@
*
* Module interface and handling of zfcp data structures.
*
* Copyright IBM Corporation 2002, 2008
* Copyright IBM Corporation 2002, 2009
*/
/*
@ -606,10 +606,12 @@ struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
INIT_LIST_HEAD(&port->unit_list_head);
INIT_WORK(&port->gid_pn_work, zfcp_erp_port_strategy_open_lookup);
INIT_WORK(&port->test_link_work, zfcp_fc_link_test_work);
INIT_WORK(&port->rport_work, zfcp_scsi_rport_work);
port->adapter = adapter;
port->d_id = d_id;
port->wwpn = wwpn;
port->rport_task = RPORT_NONE;
/* mark port unusable as long as sysfs registration is not complete */
atomic_set_mask(status | ZFCP_STATUS_COMMON_REMOVE, &port->status);

View File

@ -3,7 +3,7 @@
*
* Global definitions for the zfcp device driver.
*
* Copyright IBM Corporation 2002, 2008
* Copyright IBM Corporation 2002, 2009
*/
#ifndef ZFCP_DEF_H
@ -512,6 +512,8 @@ struct zfcp_port {
u32 supported_classes;
struct work_struct gid_pn_work;
struct work_struct test_link_work;
struct work_struct rport_work;
enum { RPORT_NONE, RPORT_ADD, RPORT_DEL } rport_task;
};
struct zfcp_unit {

View File

@ -3,7 +3,7 @@
*
* Error Recovery Procedures (ERP).
*
* Copyright IBM Corporation 2002, 2008
* Copyright IBM Corporation 2002, 2009
*/
#define KMSG_COMPONENT "zfcp"
@ -240,6 +240,7 @@ static int _zfcp_erp_adapter_reopen(struct zfcp_adapter *adapter,
int clear_mask, char *id, void *ref)
{
zfcp_erp_adapter_block(adapter, clear_mask);
zfcp_scsi_schedule_rports_block(adapter);
/* ensure propagation of failed status to new devices */
if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
@ -322,6 +323,7 @@ static void _zfcp_erp_port_forced_reopen(struct zfcp_port *port,
int clear, char *id, void *ref)
{
zfcp_erp_port_block(port, clear);
zfcp_scsi_schedule_rport_block(port);
if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_FAILED)
return;
@ -353,6 +355,7 @@ static int _zfcp_erp_port_reopen(struct zfcp_port *port, int clear, char *id,
void *ref)
{
zfcp_erp_port_block(port, clear);
zfcp_scsi_schedule_rport_block(port);
if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
/* ensure propagation of failed status to new devices */
@ -1211,37 +1214,6 @@ static void zfcp_erp_schedule_work(struct zfcp_unit *unit)
queue_work(zfcp_data.work_queue, &p->work);
}
static void zfcp_erp_rport_register(struct zfcp_port *port)
{
struct fc_rport_identifiers ids;
ids.node_name = port->wwnn;
ids.port_name = port->wwpn;
ids.port_id = port->d_id;
ids.roles = FC_RPORT_ROLE_FCP_TARGET;
port->rport = fc_remote_port_add(port->adapter->scsi_host, 0, &ids);
if (!port->rport) {
dev_err(&port->adapter->ccw_device->dev,
"Registering port 0x%016Lx failed\n",
(unsigned long long)port->wwpn);
return;
}
scsi_target_unblock(&port->rport->dev);
port->rport->maxframe_size = port->maxframe_size;
port->rport->supported_classes = port->supported_classes;
}
static void zfcp_erp_rports_del(struct zfcp_adapter *adapter)
{
struct zfcp_port *port;
list_for_each_entry(port, &adapter->port_list_head, list) {
if (!port->rport)
continue;
fc_remote_port_delete(port->rport);
port->rport = NULL;
}
}
static void zfcp_erp_action_cleanup(struct zfcp_erp_action *act, int result)
{
struct zfcp_adapter *adapter = act->adapter;
@ -1250,8 +1222,8 @@ static void zfcp_erp_action_cleanup(struct zfcp_erp_action *act, int result)
switch (act->action) {
case ZFCP_ERP_ACTION_REOPEN_UNIT:
if ((result == ZFCP_ERP_SUCCEEDED) &&
!unit->device && port->rport) {
flush_work(&port->rport_work);
if ((result == ZFCP_ERP_SUCCEEDED) && !unit->device) {
if (!(atomic_read(&unit->status) &
ZFCP_STATUS_UNIT_SCSI_WORK_PENDING))
zfcp_erp_schedule_work(unit);
@ -1261,23 +1233,17 @@ static void zfcp_erp_action_cleanup(struct zfcp_erp_action *act, int result)
case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
case ZFCP_ERP_ACTION_REOPEN_PORT:
if ((result == ZFCP_ERP_SUCCEEDED) && !port->rport)
zfcp_erp_rport_register(port);
if ((result != ZFCP_ERP_SUCCEEDED) && port->rport) {
fc_remote_port_delete(port->rport);
port->rport = NULL;
}
if (result == ZFCP_ERP_SUCCEEDED)
zfcp_scsi_schedule_rport_register(port);
zfcp_port_put(port);
break;
case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
if (result != ZFCP_ERP_SUCCEEDED) {
unregister_service_level(&adapter->service_level);
zfcp_erp_rports_del(adapter);
} else {
if (result == ZFCP_ERP_SUCCEEDED) {
register_service_level(&adapter->service_level);
schedule_work(&adapter->scan_work);
}
} else
unregister_service_level(&adapter->service_level);
zfcp_adapter_put(adapter);
break;
}

View File

@ -3,7 +3,7 @@
*
* External function declarations.
*
* Copyright IBM Corporation 2002, 2008
* Copyright IBM Corporation 2002, 2009
*/
#ifndef ZFCP_EXT_H
@ -154,6 +154,10 @@ extern int zfcp_adapter_scsi_register(struct zfcp_adapter *);
extern void zfcp_adapter_scsi_unregister(struct zfcp_adapter *);
extern char *zfcp_get_fcp_sns_info_ptr(struct fcp_rsp_iu *);
extern struct fc_function_template zfcp_transport_functions;
extern void zfcp_scsi_rport_work(struct work_struct *);
extern void zfcp_scsi_schedule_rport_register(struct zfcp_port *);
extern void zfcp_scsi_schedule_rport_block(struct zfcp_port *);
extern void zfcp_scsi_schedule_rports_block(struct zfcp_adapter *);
/* zfcp_sysfs.c */
extern struct attribute_group zfcp_sysfs_unit_attrs;

View File

@ -3,7 +3,7 @@
*
* Fibre Channel related functions for the zfcp device driver.
*
* Copyright IBM Corporation 2008
* Copyright IBM Corporation 2008, 2009
*/
#define KMSG_COMPONENT "zfcp"
@ -376,10 +376,14 @@ static void zfcp_fc_adisc_handler(unsigned long data)
port->wwnn = ls_adisc->wwnn;
if ((port->wwpn != ls_adisc->wwpn) ||
!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN))
!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN)) {
zfcp_erp_port_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
"fcadh_2", NULL);
goto out;
}
/* port is good, unblock rport without going through erp */
zfcp_scsi_schedule_rport_register(port);
out:
zfcp_port_put(port);
kfree(adisc);
@ -423,14 +427,23 @@ void zfcp_fc_link_test_work(struct work_struct *work)
container_of(work, struct zfcp_port, test_link_work);
int retval;
if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_UNBLOCKED)) {
zfcp_port_put(port);
return; /* port erp is running and will update rport status */
}
zfcp_port_get(port);
port->rport_task = RPORT_DEL;
zfcp_scsi_rport_work(&port->rport_work);
retval = zfcp_fc_adisc(port);
if (retval == 0)
return;
/* send of ADISC was not possible */
zfcp_erp_port_forced_reopen(port, 0, "fcltwk1", NULL);
zfcp_port_put(port);
if (retval != -EBUSY)
zfcp_erp_port_forced_reopen(port, 0, "fcltwk1", NULL);
}
/**

View File

@ -3,7 +3,7 @@
*
* Implementation of FSF commands.
*
* Copyright IBM Corporation 2002, 2008
* Copyright IBM Corporation 2002, 2009
*/
#define KMSG_COMPONENT "zfcp"
@ -177,6 +177,7 @@ static void zfcp_fsf_link_down_info_eval(struct zfcp_fsf_req *req, char *id,
return;
atomic_set_mask(ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED, &adapter->status);
zfcp_scsi_schedule_rports_block(adapter);
if (!link_down)
goto out;

View File

@ -3,7 +3,7 @@
*
* Interface to Linux SCSI midlayer.
*
* Copyright IBM Corporation 2002, 2008
* Copyright IBM Corporation 2002, 2009
*/
#define KMSG_COMPONENT "zfcp"
@ -57,8 +57,8 @@ static int zfcp_scsi_queuecommand(struct scsi_cmnd *scpnt,
{
struct zfcp_unit *unit;
struct zfcp_adapter *adapter;
int status;
int ret;
int status, scsi_result, ret;
struct fc_rport *rport = starget_to_rport(scsi_target(scpnt->device));
/* reset the status for this request */
scpnt->result = 0;
@ -80,6 +80,14 @@ static int zfcp_scsi_queuecommand(struct scsi_cmnd *scpnt,
return 0;
}
scsi_result = fc_remote_port_chkready(rport);
if (unlikely(scsi_result)) {
scpnt->result = scsi_result;
zfcp_scsi_dbf_event_result("fail", 4, adapter, scpnt, NULL);
scpnt->scsi_done(scpnt);
return 0;
}
status = atomic_read(&unit->status);
if (unlikely((status & ZFCP_STATUS_COMMON_ERP_FAILED) ||
!(status & ZFCP_STATUS_COMMON_RUNNING))) {
@ -473,6 +481,109 @@ static void zfcp_set_rport_dev_loss_tmo(struct fc_rport *rport, u32 timeout)
rport->dev_loss_tmo = timeout;
}
/**
* zfcp_scsi_dev_loss_tmo_callbk - Free any reference to rport
* @rport: The rport that is about to be deleted.
*/
static void zfcp_scsi_dev_loss_tmo_callbk(struct fc_rport *rport)
{
struct zfcp_port *port = rport->dd_data;
write_lock_irq(&zfcp_data.config_lock);
port->rport = NULL;
write_unlock_irq(&zfcp_data.config_lock);
}
/**
* zfcp_scsi_terminate_rport_io - Terminate all I/O on a rport
* @rport: The FC rport where to teminate I/O
*
* Abort all pending SCSI commands for a port by closing the
* port. Using a reopen for avoids a conflict with a shutdown
* overwriting a reopen.
*/
static void zfcp_scsi_terminate_rport_io(struct fc_rport *rport)
{
struct zfcp_port *port = rport->dd_data;
zfcp_erp_port_reopen(port, 0, "sctrpi1", NULL);
}
static void zfcp_scsi_rport_register(struct zfcp_port *port)
{
struct fc_rport_identifiers ids;
struct fc_rport *rport;
ids.node_name = port->wwnn;
ids.port_name = port->wwpn;
ids.port_id = port->d_id;
ids.roles = FC_RPORT_ROLE_FCP_TARGET;
rport = fc_remote_port_add(port->adapter->scsi_host, 0, &ids);
if (!rport) {
dev_err(&port->adapter->ccw_device->dev,
"Registering port 0x%016Lx failed\n",
(unsigned long long)port->wwpn);
return;
}
rport->dd_data = port;
rport->maxframe_size = port->maxframe_size;
rport->supported_classes = port->supported_classes;
port->rport = rport;
}
static void zfcp_scsi_rport_block(struct zfcp_port *port)
{
if (port->rport)
fc_remote_port_delete(port->rport);
}
void zfcp_scsi_schedule_rport_register(struct zfcp_port *port)
{
zfcp_port_get(port);
port->rport_task = RPORT_ADD;
if (!queue_work(zfcp_data.work_queue, &port->rport_work))
zfcp_port_put(port);
}
void zfcp_scsi_schedule_rport_block(struct zfcp_port *port)
{
zfcp_port_get(port);
port->rport_task = RPORT_DEL;
if (!queue_work(zfcp_data.work_queue, &port->rport_work))
zfcp_port_put(port);
}
void zfcp_scsi_schedule_rports_block(struct zfcp_adapter *adapter)
{
struct zfcp_port *port;
list_for_each_entry(port, &adapter->port_list_head, list)
zfcp_scsi_schedule_rport_block(port);
}
void zfcp_scsi_rport_work(struct work_struct *work)
{
struct zfcp_port *port = container_of(work, struct zfcp_port,
rport_work);
while (port->rport_task) {
if (port->rport_task == RPORT_ADD) {
port->rport_task = RPORT_NONE;
zfcp_scsi_rport_register(port);
} else {
port->rport_task = RPORT_NONE;
zfcp_scsi_rport_block(port);
}
}
zfcp_port_put(port);
}
struct fc_function_template zfcp_transport_functions = {
.show_starget_port_id = 1,
.show_starget_port_name = 1,
@ -491,6 +602,8 @@ struct fc_function_template zfcp_transport_functions = {
.reset_fc_host_stats = zfcp_reset_fc_host_stats,
.set_rport_dev_loss_tmo = zfcp_set_rport_dev_loss_tmo,
.get_host_port_state = zfcp_get_host_port_state,
.dev_loss_tmo_callbk = zfcp_scsi_dev_loss_tmo_callbk,
.terminate_rport_io = zfcp_scsi_terminate_rport_io,
.show_host_port_state = 1,
/* no functions registered for following dynamic attributes but
directly set by LLDD */