zfcp_erp.c

linux-2.6.15.6

/* 
 * 
 * linux/drivers/s390/scsi/zfcp_erp.c 
 * 
 * FCP adapter driver for IBM eServer zSeries 
 * 
 * (C) Copyright IBM Corp. 2002, 2004
 *
 * Author(s): Martin Peschke <[e-mail]> 
 *            Raimund Schroeder <[e-mail]> 
 *            Aron Zeh
 *            Wolfgang Taphorn
 *            Stefan Bader <[e-mail]> 
 *            Heiko Carstens <[e-mail]> 
 *            Andreas Herrmann <[e-mail]>
 * 
 * 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, 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., 675 Mass Ave, Cambridge, MA 02139, USA. 
 */

#define ZFCP_LOG_AREA			ZFCP_LOG_AREA_ERP

#define ZFCP_ERP_REVISION "$Revision: 1.86 $"

#include "zfcp_ext.h"

static int zfcp_erp_adisc(struct zfcp_port *);
static void zfcp_erp_adisc_handler(unsigned long);

static int zfcp_erp_adapter_reopen_internal(struct zfcp_adapter *, int);
static int zfcp_erp_port_forced_reopen_internal(struct zfcp_port *, int);
static int zfcp_erp_port_reopen_internal(struct zfcp_port *, int);
static int zfcp_erp_unit_reopen_internal(struct zfcp_unit *, int);

static int zfcp_erp_port_reopen_all_internal(struct zfcp_adapter *, int);
static int zfcp_erp_unit_reopen_all_internal(struct zfcp_port *, int);

static void zfcp_erp_adapter_block(struct zfcp_adapter *, int);
static void zfcp_erp_adapter_unblock(struct zfcp_adapter *);
static void zfcp_erp_port_block(struct zfcp_port *, int);
static void zfcp_erp_port_unblock(struct zfcp_port *);
static void zfcp_erp_unit_block(struct zfcp_unit *, int);
static void zfcp_erp_unit_unblock(struct zfcp_unit *);

static int zfcp_erp_thread(void *);

static int zfcp_erp_strategy(struct zfcp_erp_action *);

static int zfcp_erp_strategy_do_action(struct zfcp_erp_action *);
static int zfcp_erp_strategy_memwait(struct zfcp_erp_action *);
static int zfcp_erp_strategy_check_target(struct zfcp_erp_action *, int);
static int zfcp_erp_strategy_check_unit(struct zfcp_unit *, int);
static int zfcp_erp_strategy_check_port(struct zfcp_port *, int);
static int zfcp_erp_strategy_check_adapter(struct zfcp_adapter *, int);
static int zfcp_erp_strategy_statechange(int, u32, struct zfcp_adapter *,
					 struct zfcp_port *,
					 struct zfcp_unit *, int);
static inline int zfcp_erp_strategy_statechange_detected(atomic_t *, u32);
static int zfcp_erp_strategy_followup_actions(int, struct zfcp_adapter *,
					      struct zfcp_port *,
					      struct zfcp_unit *, int);
static int zfcp_erp_strategy_check_queues(struct zfcp_adapter *);
static int zfcp_erp_strategy_check_action(struct zfcp_erp_action *, int);

static int zfcp_erp_adapter_strategy(struct zfcp_erp_action *);
static int zfcp_erp_adapter_strategy_generic(struct zfcp_erp_action *, int);
static int zfcp_erp_adapter_strategy_close(struct zfcp_erp_action *);
static int zfcp_erp_adapter_strategy_close_qdio(struct zfcp_erp_action *);
static int zfcp_erp_adapter_strategy_close_fsf(struct zfcp_erp_action *);
static int zfcp_erp_adapter_strategy_open(struct zfcp_erp_action *);
static int zfcp_erp_adapter_strategy_open_qdio(struct zfcp_erp_action *);
static int zfcp_erp_adapter_strategy_open_fsf(struct zfcp_erp_action *);
static int zfcp_erp_adapter_strategy_open_fsf_xconfig(struct zfcp_erp_action *);
static int zfcp_erp_adapter_strategy_open_fsf_xport(struct zfcp_erp_action *);
static int zfcp_erp_adapter_strategy_open_fsf_statusread(
	struct zfcp_erp_action *);

static int zfcp_erp_port_forced_strategy(struct zfcp_erp_action *);
static int zfcp_erp_port_forced_strategy_close(struct zfcp_erp_action *);

static int zfcp_erp_port_strategy(struct zfcp_erp_action *);
static int zfcp_erp_port_strategy_clearstati(struct zfcp_port *);
static int zfcp_erp_port_strategy_close(struct zfcp_erp_action *);
static int zfcp_erp_port_strategy_open(struct zfcp_erp_action *);
static int zfcp_erp_port_strategy_open_nameserver(struct zfcp_erp_action *);
static int zfcp_erp_port_strategy_open_nameserver_wakeup(
	struct zfcp_erp_action *);
static int zfcp_erp_port_strategy_open_common(struct zfcp_erp_action *);
static int zfcp_erp_port_strategy_open_common_lookup(struct zfcp_erp_action *);
static int zfcp_erp_port_strategy_open_port(struct zfcp_erp_action *);

static int zfcp_erp_unit_strategy(struct zfcp_erp_action *);
static int zfcp_erp_unit_strategy_clearstati(struct zfcp_unit *);
static int zfcp_erp_unit_strategy_close(struct zfcp_erp_action *);
static int zfcp_erp_unit_strategy_open(struct zfcp_erp_action *);

static int zfcp_erp_action_dismiss_adapter(struct zfcp_adapter *);
static int zfcp_erp_action_dismiss_port(struct zfcp_port *);
static int zfcp_erp_action_dismiss_unit(struct zfcp_unit *);
static int zfcp_erp_action_dismiss(struct zfcp_erp_action *);

static int zfcp_erp_action_enqueue(int, struct zfcp_adapter *,
				   struct zfcp_port *, struct zfcp_unit *);
static int zfcp_erp_action_dequeue(struct zfcp_erp_action *);
static void zfcp_erp_action_cleanup(int, struct zfcp_adapter *,
				    struct zfcp_port *, struct zfcp_unit *,
				    int);

static void zfcp_erp_action_ready(struct zfcp_erp_action *);
static int  zfcp_erp_action_exists(struct zfcp_erp_action *);

static inline void zfcp_erp_action_to_ready(struct zfcp_erp_action *);
static inline void zfcp_erp_action_to_running(struct zfcp_erp_action *);

static void zfcp_erp_memwait_handler(unsigned long);
static void zfcp_erp_timeout_handler(unsigned long);
static inline void zfcp_erp_timeout_init(struct zfcp_erp_action *);

/**
 * zfcp_fsf_request_timeout_handler - called if a request timed out
 * @data: pointer to adapter for handler function
 *
 * This function needs to be called if requests (ELS, Generic Service,
 * or SCSI commands) exceed a certain time limit. The assumption is
 * that after the time limit the adapter get stuck. So we trigger a reopen of
 * the adapter. This should not be used for error recovery, SCSI abort
 * commands and SCSI requests from SCSI mid-layer.
 */
void
zfcp_fsf_request_timeout_handler(unsigned long data)
{
	struct zfcp_adapter *adapter;

	adapter = (struct zfcp_adapter *) data;

	zfcp_erp_adapter_reopen(adapter, 0);
}

/*
 * function:	zfcp_fsf_scsi_er_timeout_handler
 *
 * purpose:     This function needs to be called whenever a SCSI error recovery
 *              action (abort/reset) does not return.
 *              Re-opening the adapter means that the command can be returned
 *              by zfcp (it is guarranteed that it does not return via the
 *              adapter anymore). The buffer can then be used again.
 *    
 * returns:     sod all
 */
void
zfcp_fsf_scsi_er_timeout_handler(unsigned long data)
{
	struct zfcp_adapter *adapter = (struct zfcp_adapter *) data;

	ZFCP_LOG_NORMAL("warning: SCSI error recovery timed out. "
			"Restarting all operations on the adapter %s\n",
			zfcp_get_busid_by_adapter(adapter));
	debug_text_event(adapter->erp_dbf, 1, "eh_lmem_tout");
	zfcp_erp_adapter_reopen(adapter, 0);

	return;
}

/*
 * function:	
 *
 * purpose:	called if an adapter failed,
 *		initiates adapter recovery which is done
 *		asynchronously
 *
 * returns:	0	- initiated action succesfully
 *		<0	- failed to initiate action
 */
int
zfcp_erp_adapter_reopen_internal(struct zfcp_adapter *adapter, int clear_mask)
{
	int retval;

	debug_text_event(adapter->erp_dbf, 5, "a_ro");
	ZFCP_LOG_DEBUG("reopen adapter %s\n",
		       zfcp_get_busid_by_adapter(adapter));

	zfcp_erp_adapter_block(adapter, clear_mask);

	if (atomic_test_mask(ZFCP_STATUS_COMMON_ERP_FAILED, &adapter->status)) {
		ZFCP_LOG_DEBUG("skipped reopen of failed adapter %s\n",
			       zfcp_get_busid_by_adapter(adapter));
		debug_text_event(adapter->erp_dbf, 5, "a_ro_f");
		/* ensure propagation of failed status to new devices */
		zfcp_erp_adapter_failed(adapter);
		retval = -EIO;
		goto out;
	}
	retval = zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_ADAPTER,
					 adapter, NULL, NULL);

 out:
	return retval;
}

/*
 * function:	
 *
 * purpose:	Wrappper for zfcp_erp_adapter_reopen_internal
 *              used to ensure the correct locking
 *
 * returns:	0	- initiated action succesfully
 *		<0	- failed to initiate action
 */
int
zfcp_erp_adapter_reopen(struct zfcp_adapter *adapter, int clear_mask)
{
	int retval;
	unsigned long flags;

	read_lock_irqsave(&zfcp_data.config_lock, flags);
	write_lock(&adapter->erp_lock);
	retval = zfcp_erp_adapter_reopen_internal(adapter, clear_mask);
	write_unlock(&adapter->erp_lock);
	read_unlock_irqrestore(&zfcp_data.config_lock, flags);

	return retval;
}

/*
 * function:	
 *
 * purpose:	
 *
 * returns:
 */
int
zfcp_erp_adapter_shutdown(struct zfcp_adapter *adapter, int clear_mask)
{
	int retval;

	retval = zfcp_erp_adapter_reopen(adapter,
					 ZFCP_STATUS_COMMON_RUNNING |
					 ZFCP_STATUS_COMMON_ERP_FAILED |
					 clear_mask);

	return retval;
}

/*
 * function:	
 *
 * purpose:	
 *
 * returns:
 */
int
zfcp_erp_port_shutdown(struct zfcp_port *port, int clear_mask)
{
	int retval;

	retval = zfcp_erp_port_reopen(port,
				      ZFCP_STATUS_COMMON_RUNNING |
				      ZFCP_STATUS_COMMON_ERP_FAILED |
				      clear_mask);

	return retval;
}

/*
 * function:	
 *
 * purpose:	
 *
 * returns:
 */
int
zfcp_erp_unit_shutdown(struct zfcp_unit *unit, int clear_mask)
{
	int retval;

	retval = zfcp_erp_unit_reopen(unit,
				      ZFCP_STATUS_COMMON_RUNNING |
				      ZFCP_STATUS_COMMON_ERP_FAILED |
				      clear_mask);

	return retval;
}


/**
 * zfcp_erp_adisc - send ADISC ELS command
 * @port: port structure
 */
int
zfcp_erp_adisc(struct zfcp_port *port)
{
	struct zfcp_adapter *adapter = port->adapter;
	struct zfcp_send_els *send_els;
	struct zfcp_ls_adisc *adisc;
	void *address = NULL;
	int retval = 0;
	struct timer_list *timer;

	send_els = kmalloc(sizeof(struct zfcp_send_els), GFP_ATOMIC);
	if (send_els == NULL)
		goto nomem;
	memset(send_els, 0, sizeof(*send_els));

	send_els->req = kmalloc(sizeof(struct scatterlist), GFP_ATOMIC);
	if (send_els->req == NULL)
		goto nomem;
	memset(send_els->req, 0, sizeof(*send_els->req));

	send_els->resp = kmalloc(sizeof(struct scatterlist), GFP_ATOMIC);
	if (send_els->resp == NULL)
		goto nomem;
	memset(send_els->resp, 0, sizeof(*send_els->resp));

	address = (void *) get_zeroed_page(GFP_ATOMIC);
	if (address == NULL)
		goto nomem;

	zfcp_address_to_sg(address, send_els->req);
	address += PAGE_SIZE >> 1;
	zfcp_address_to_sg(address, send_els->resp);
	send_els->req_count = send_els->resp_count = 1;

	send_els->adapter = adapter;
	send_els->port = port;
	send_els->d_id = port->d_id;
	send_els->handler = zfcp_erp_adisc_handler;
	send_els->handler_data = (unsigned long) send_els;

	adisc = zfcp_sg_to_address(send_els->req);
	send_els->ls_code = adisc->code = ZFCP_LS_ADISC;

	send_els->req->length = sizeof(struct zfcp_ls_adisc);
	send_els->resp->length = sizeof(struct zfcp_ls_adisc_acc);

	/* acc. to FC-FS, hard_nport_id in ADISC should not be set for ports
	   without FC-AL-2 capability, so we don't set it */
	adisc->wwpn = fc_host_port_name(adapter->scsi_host);
	adisc->wwnn = fc_host_node_name(adapter->scsi_host);
	adisc->nport_id = fc_host_port_id(adapter->scsi_host);
	ZFCP_LOG_INFO("ADISC request from s_id 0x%08x to d_id 0x%08x "
		      "(wwpn=0x%016Lx, wwnn=0x%016Lx, "
		      "hard_nport_id=0x%08x, nport_id=0x%08x)\n",
		      adisc->nport_id, send_els->d_id, (wwn_t) adisc->wwpn,
		      (wwn_t) adisc->wwnn, adisc->hard_nport_id,
		      adisc->nport_id);

	timer = kmalloc(sizeof(struct timer_list), GFP_ATOMIC);
	if (!timer)
		goto nomem;

	init_timer(timer);
	timer->function = zfcp_fsf_request_timeout_handler;
	timer->data = (unsigned long) adapter;
	timer->expires = ZFCP_FSF_REQUEST_TIMEOUT;
	send_els->timer = timer;

	retval = zfcp_fsf_send_els(send_els);
	if (retval != 0) {
		ZFCP_LOG_NORMAL("error: initiation of Send ELS failed for port "
				"0x%08x on adapter %s\n", send_els->d_id,
				zfcp_get_busid_by_adapter(adapter));
		del_timer(send_els->timer);
		goto freemem;
	}

	goto out;

 nomem:
	retval = -ENOMEM;
 freemem:
	if (address != NULL)
		__free_pages(send_els->req->page, 0);
	if (send_els != NULL) {
		kfree(send_els->timer);
		kfree(send_els->req);
		kfree(send_els->resp);
		kfree(send_els);
	}
 out:
	return retval;
}


/**
 * zfcp_erp_adisc_handler - handler for ADISC ELS command
 * @data: pointer to struct zfcp_send_els
 *
 * If ADISC failed (LS_RJT or timed out) forced reopen of the port is triggered.
 */
void
zfcp_erp_adisc_handler(unsigned long data)
{
	struct zfcp_send_els *send_els;
	struct zfcp_port *port;
	struct zfcp_adapter *adapter;
	u32 d_id;
	struct zfcp_ls_adisc_acc *adisc;

	send_els = (struct zfcp_send_els *) data;

	del_timer(send_els->timer);

	adapter = send_els->adapter;
	port = send_els->port;
	d_id = send_els->d_id;

	/* request rejected or timed out */
	if (send_els->status != 0) {
		ZFCP_LOG_NORMAL("ELS request rejected/timed out, "
				"force physical port reopen "
				"(adapter %s, port d_id=0x%08x)\n",
				zfcp_get_busid_by_adapter(adapter), d_id);
		debug_text_event(adapter->erp_dbf, 3, "forcreop");
		if (zfcp_erp_port_forced_reopen(port, 0))
			ZFCP_LOG_NORMAL("failed reopen of port "
					"(adapter %s, wwpn=0x%016Lx)\n",
					zfcp_get_busid_by_port(port),
					port->wwpn);
		goto out;
	}

	adisc = zfcp_sg_to_address(send_els->resp);

	ZFCP_LOG_INFO("ADISC response from d_id 0x%08x to s_id "
		      "0x%08x (wwpn=0x%016Lx, wwnn=0x%016Lx, "
		      "hard_nport_id=0x%08x, nport_id=0x%08x)\n",
		      d_id, fc_host_port_id(adapter->scsi_host),
		      (wwn_t) adisc->wwpn, (wwn_t) adisc->wwnn,
		      adisc->hard_nport_id, adisc->nport_id);

	/* set wwnn for port */
	if (port->wwnn == 0)
		port->wwnn = adisc->wwnn;

	if (port->wwpn != adisc->wwpn) {
		ZFCP_LOG_NORMAL("d_id assignment changed, reopening "
				"port (adapter %s, wwpn=0x%016Lx, "
				"adisc_resp_wwpn=0x%016Lx)\n",
				zfcp_get_busid_by_port(port),
				port->wwpn, (wwn_t) adisc->wwpn);
		if (zfcp_erp_port_reopen(port, 0))
			ZFCP_LOG_NORMAL("failed reopen of port "
					"(adapter %s, wwpn=0x%016Lx)\n",
					zfcp_get_busid_by_port(port),
					port->wwpn);
	}

 out:
	zfcp_port_put(port);
	__free_pages(send_els->req->page, 0);
	kfree(send_els->timer);
	kfree(send_els->req);