zfcp_fsf.c

linux-2.6.15.6

/*
 *
 * linux/drivers/s390/scsi/zfcp_fsf.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]>
 *            Volker Sameske <[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_FSF_C_REVISION "$Revision: 1.92 $"

#include "zfcp_ext.h"

static int zfcp_fsf_exchange_config_data_handler(struct zfcp_fsf_req *);
static void zfcp_fsf_exchange_port_data_handler(struct zfcp_fsf_req *);
static int zfcp_fsf_open_port_handler(struct zfcp_fsf_req *);
static int zfcp_fsf_close_port_handler(struct zfcp_fsf_req *);
static int zfcp_fsf_close_physical_port_handler(struct zfcp_fsf_req *);
static int zfcp_fsf_open_unit_handler(struct zfcp_fsf_req *);
static int zfcp_fsf_close_unit_handler(struct zfcp_fsf_req *);
static int zfcp_fsf_send_fcp_command_handler(struct zfcp_fsf_req *);
static int zfcp_fsf_send_fcp_command_task_handler(struct zfcp_fsf_req *);
static int zfcp_fsf_send_fcp_command_task_management_handler(
	struct zfcp_fsf_req *);
static int zfcp_fsf_abort_fcp_command_handler(struct zfcp_fsf_req *);
static int zfcp_fsf_status_read_handler(struct zfcp_fsf_req *);
static int zfcp_fsf_send_ct_handler(struct zfcp_fsf_req *);
static int zfcp_fsf_send_els_handler(struct zfcp_fsf_req *);
static int zfcp_fsf_control_file_handler(struct zfcp_fsf_req *);
static inline int zfcp_fsf_req_sbal_check(
	unsigned long *, struct zfcp_qdio_queue *, int);
static inline int zfcp_use_one_sbal(
	struct scatterlist *, int, struct scatterlist *, int);
static struct zfcp_fsf_req *zfcp_fsf_req_alloc(mempool_t *, int);
static int zfcp_fsf_req_send(struct zfcp_fsf_req *, struct timer_list *);
static int zfcp_fsf_protstatus_eval(struct zfcp_fsf_req *);
static int zfcp_fsf_fsfstatus_eval(struct zfcp_fsf_req *);
static int zfcp_fsf_fsfstatus_qual_eval(struct zfcp_fsf_req *);
static void zfcp_fsf_link_down_info_eval(struct zfcp_adapter *,
	struct fsf_link_down_info *);
static int zfcp_fsf_req_dispatch(struct zfcp_fsf_req *);
static void zfcp_fsf_req_dismiss(struct zfcp_fsf_req *);

/* association between FSF command and FSF QTCB type */
static u32 fsf_qtcb_type[] = {
	[FSF_QTCB_FCP_CMND] =             FSF_IO_COMMAND,
	[FSF_QTCB_ABORT_FCP_CMND] =       FSF_SUPPORT_COMMAND,
	[FSF_QTCB_OPEN_PORT_WITH_DID] =   FSF_SUPPORT_COMMAND,
	[FSF_QTCB_OPEN_LUN] =             FSF_SUPPORT_COMMAND,
	[FSF_QTCB_CLOSE_LUN] =            FSF_SUPPORT_COMMAND,
	[FSF_QTCB_CLOSE_PORT] =           FSF_SUPPORT_COMMAND,
	[FSF_QTCB_CLOSE_PHYSICAL_PORT] =  FSF_SUPPORT_COMMAND,
	[FSF_QTCB_SEND_ELS] =             FSF_SUPPORT_COMMAND,
	[FSF_QTCB_SEND_GENERIC] =         FSF_SUPPORT_COMMAND,
	[FSF_QTCB_EXCHANGE_CONFIG_DATA] = FSF_CONFIG_COMMAND,
	[FSF_QTCB_EXCHANGE_PORT_DATA] =   FSF_PORT_COMMAND,
	[FSF_QTCB_DOWNLOAD_CONTROL_FILE] = FSF_SUPPORT_COMMAND,
	[FSF_QTCB_UPLOAD_CONTROL_FILE] =  FSF_SUPPORT_COMMAND
};

static const char zfcp_act_subtable_type[5][8] = {
	"unknown", "OS", "WWPN", "DID", "LUN"
};

/****************************************************************/
/*************** FSF related Functions  *************************/
/****************************************************************/

#define ZFCP_LOG_AREA			ZFCP_LOG_AREA_FSF

/*
 * function:	zfcp_fsf_req_alloc
 *
 * purpose:     Obtains an fsf_req and potentially a qtcb (for all but 
 *              unsolicited requests) via helper functions
 *              Does some initial fsf request set-up.
 *              
 * returns:	pointer to allocated fsf_req if successfull
 *              NULL otherwise
 *
 * locks:       none
 *
 */
static struct zfcp_fsf_req *
zfcp_fsf_req_alloc(mempool_t *pool, int req_flags)
{
	size_t size;
	void *ptr;
	struct zfcp_fsf_req *fsf_req = NULL;

	if (req_flags & ZFCP_REQ_NO_QTCB)
		size = sizeof(struct zfcp_fsf_req);
	else
		size = sizeof(struct zfcp_fsf_req_pool_element);

	if (likely(pool != NULL))
		ptr = mempool_alloc(pool, GFP_ATOMIC);
	else
		ptr = kmalloc(size, GFP_ATOMIC);

	if (unlikely(NULL == ptr))
		goto out;

	memset(ptr, 0, size);

	if (req_flags & ZFCP_REQ_NO_QTCB) {
		fsf_req = (struct zfcp_fsf_req *) ptr;
	} else {
		fsf_req = &((struct zfcp_fsf_req_pool_element *) ptr)->fsf_req;
		fsf_req->qtcb =
			&((struct zfcp_fsf_req_pool_element *) ptr)->qtcb;
	}

	fsf_req->pool = pool;

 out:
	return fsf_req;
}

/*
 * function:	zfcp_fsf_req_free
 *
 * purpose:     Frees the memory of an fsf_req (and potentially a qtcb) or
 *              returns it into the pool via helper functions.
 *
 * returns:     sod all
 *
 * locks:       none
 */
void
zfcp_fsf_req_free(struct zfcp_fsf_req *fsf_req)
{
	if (likely(fsf_req->pool != NULL))
		mempool_free(fsf_req, fsf_req->pool);
	else
		kfree(fsf_req);
}

/*
 * function:	
 *
 * purpose:	
 *
 * returns:
 *
 * note: qdio queues shall be down (no ongoing inbound processing)
 */
int
zfcp_fsf_req_dismiss_all(struct zfcp_adapter *adapter)
{
	struct zfcp_fsf_req *fsf_req, *tmp;
	unsigned long flags;
	LIST_HEAD(remove_queue);

	spin_lock_irqsave(&adapter->fsf_req_list_lock, flags);
	list_splice_init(&adapter->fsf_req_list_head, &remove_queue);
	atomic_set(&adapter->fsf_reqs_active, 0);
	spin_unlock_irqrestore(&adapter->fsf_req_list_lock, flags);

	list_for_each_entry_safe(fsf_req, tmp, &remove_queue, list) {
		list_del(&fsf_req->list);
		zfcp_fsf_req_dismiss(fsf_req);
	}

	return 0;
}

/*
 * function:	
 *
 * purpose:	
 *
 * returns:
 */
static void
zfcp_fsf_req_dismiss(struct zfcp_fsf_req *fsf_req)
{
	fsf_req->status |= ZFCP_STATUS_FSFREQ_DISMISSED;
	zfcp_fsf_req_complete(fsf_req);
}

/*
 * function:    zfcp_fsf_req_complete
 *
 * purpose:	Updates active counts and timers for openfcp-reqs
 *              May cleanup request after req_eval returns
 *
 * returns:	0 - success
 *		!0 - failure
 *
 * context:	
 */
int
zfcp_fsf_req_complete(struct zfcp_fsf_req *fsf_req)
{
	int retval = 0;
	int cleanup;

	if (unlikely(fsf_req->fsf_command == FSF_QTCB_UNSOLICITED_STATUS)) {
		ZFCP_LOG_DEBUG("Status read response received\n");
		/*
		 * Note: all cleanup handling is done in the callchain of
		 * the function call-chain below.
		 */
		zfcp_fsf_status_read_handler(fsf_req);
		goto out;
	} else
		zfcp_fsf_protstatus_eval(fsf_req);

	/*
	 * fsf_req may be deleted due to waking up functions, so 
	 * cleanup is saved here and used later 
	 */
	if (likely(fsf_req->status & ZFCP_STATUS_FSFREQ_CLEANUP))
		cleanup = 1;
	else
		cleanup = 0;

	fsf_req->status |= ZFCP_STATUS_FSFREQ_COMPLETED;

	/* cleanup request if requested by initiator */
	if (likely(cleanup)) {
		ZFCP_LOG_TRACE("removing FSF request %p\n", fsf_req);
		/*
		 * lock must not be held here since it will be
		 * grabed by the called routine, too
		 */
		zfcp_fsf_req_free(fsf_req);
	} else {
		/* notify initiator waiting for the requests completion */
		ZFCP_LOG_TRACE("waking initiator of FSF request %p\n",fsf_req);
		/*
		 * FIXME: Race! We must not access fsf_req here as it might have been
		 * cleaned up already due to the set ZFCP_STATUS_FSFREQ_COMPLETED
		 * flag. It's an improbable case. But, we have the same paranoia for
		 * the cleanup flag already.
		 * Might better be handled using complete()?
		 * (setting the flag and doing wakeup ought to be atomic
		 *  with regard to checking the flag as long as waitqueue is
		 *  part of the to be released structure)
		 */
		wake_up(&fsf_req->completion_wq);
	}

 out:
	return retval;
}

/*
 * function:    zfcp_fsf_protstatus_eval
 *
 * purpose:	evaluates the QTCB of the finished FSF request
 *		and initiates appropriate actions
 *		(usually calling FSF command specific handlers)
 *
 * returns:	
 *
 * context:	
 *
 * locks:
 */
static int
zfcp_fsf_protstatus_eval(struct zfcp_fsf_req *fsf_req)
{
	int retval = 0;
	struct zfcp_adapter *adapter = fsf_req->adapter;
	struct fsf_qtcb *qtcb = fsf_req->qtcb;
	union fsf_prot_status_qual *prot_status_qual =
		&qtcb->prefix.prot_status_qual;

	zfcp_hba_dbf_event_fsf_response(fsf_req);

	if (fsf_req->status & ZFCP_STATUS_FSFREQ_DISMISSED) {
		ZFCP_LOG_DEBUG("fsf_req 0x%lx has been dismissed\n",
			       (unsigned long) fsf_req);
		fsf_req->status |= ZFCP_STATUS_FSFREQ_ERROR |
			ZFCP_STATUS_FSFREQ_RETRY; /* only for SCSI cmnds. */
		goto skip_protstatus;
	}

	/* log additional information provided by FSF (if any) */
	if (unlikely(qtcb->header.log_length)) {
		/* do not trust them ;-) */
		if (qtcb->header.log_start > sizeof(struct fsf_qtcb)) {
			ZFCP_LOG_NORMAL
			    ("bug: ULP (FSF logging) log data starts "
			     "beyond end of packet header. Ignored. "
			     "(start=%i, size=%li)\n",
			     qtcb->header.log_start,
			     sizeof(struct fsf_qtcb));
			goto forget_log;
		}
		if ((size_t) (qtcb->header.log_start + qtcb->header.log_length)
		    > sizeof(struct fsf_qtcb)) {
			ZFCP_LOG_NORMAL("bug: ULP (FSF logging) log data ends "
					"beyond end of packet header. Ignored. "
					"(start=%i, length=%i, size=%li)\n",
					qtcb->header.log_start,
					qtcb->header.log_length,
					sizeof(struct fsf_qtcb));
			goto forget_log;
		}
		ZFCP_LOG_TRACE("ULP log data: \n");
		ZFCP_HEX_DUMP(ZFCP_LOG_LEVEL_TRACE,
			      (char *) qtcb + qtcb->header.log_start,
			      qtcb->header.log_length);
	}
 forget_log:

	/* evaluate FSF Protocol Status */
	switch (qtcb->prefix.prot_status) {

	case FSF_PROT_GOOD:
	case FSF_PROT_FSF_STATUS_PRESENTED:
		break;

	case FSF_PROT_QTCB_VERSION_ERROR:
		ZFCP_LOG_NORMAL("error: The adapter %s contains "
				"microcode of version 0x%x, the device driver "
				"only supports 0x%x. Aborting.\n",
				zfcp_get_busid_by_adapter(adapter),
				prot_status_qual->version_error.fsf_version,
				ZFCP_QTCB_VERSION);
		zfcp_erp_adapter_shutdown(adapter, 0);
		fsf_req->status |= ZFCP_STATUS_FSFREQ_ERROR;
		break;

	case FSF_PROT_SEQ_NUMB_ERROR:
		ZFCP_LOG_NORMAL("bug: Sequence number mismatch between "
				"driver (0x%x) and adapter %s (0x%x). "
				"Restarting all operations on this adapter.\n",
				qtcb->prefix.req_seq_no,
				zfcp_get_busid_by_adapter(adapter),
				prot_status_qual->sequence_error.exp_req_seq_no);
		zfcp_erp_adapter_reopen(adapter, 0);
		fsf_req->status |= ZFCP_STATUS_FSFREQ_RETRY;
		fsf_req->status |= ZFCP_STATUS_FSFREQ_ERROR;
		break;

	case FSF_PROT_UNSUPP_QTCB_TYPE:
		ZFCP_LOG_NORMAL("error: Packet header type used by the "
				"device driver is incompatible with "
				"that used on adapter %s. "
				"Stopping all operations on this adapter.\n",
				zfcp_get_busid_by_adapter(adapter));
		zfcp_erp_adapter_shutdown(adapter, 0);
		fsf_req->status |= ZFCP_STATUS_FSFREQ_ERROR;
		break;

	case FSF_PROT_HOST_CONNECTION_INITIALIZING:
		fsf_req->status |= ZFCP_STATUS_FSFREQ_ERROR;
		atomic_set_mask(ZFCP_STATUS_ADAPTER_HOST_CON_INIT,
				&(adapter->status));
		break;

	case FSF_PROT_DUPLICATE_REQUEST_ID:
			ZFCP_LOG_NORMAL("bug: The request identifier 0x%Lx "
					"to the adapter %s is ambiguous. "
				"Stopping all operations on this adapter.\n",
				*(unsigned long long*)
				(&qtcb->bottom.support.req_handle),
					zfcp_get_busid_by_adapter(adapter));
		zfcp_erp_adapter_shutdown(adapter, 0);
		fsf_req->status |= ZFCP_STATUS_FSFREQ_ERROR;
		break;

	case FSF_PROT_LINK_DOWN:
		zfcp_fsf_link_down_info_eval(adapter,
					     &prot_status_qual->link_down_info);
		fsf_req->status |= ZFCP_STATUS_FSFREQ_ERROR;
		break;

	case FSF_PROT_REEST_QUEUE:
		ZFCP_LOG_NORMAL("The local link to adapter with "
			      "%s was re-plugged. "
			      "Re-starting operations on this adapter.\n",
			      zfcp_get_busid_by_adapter(adapter));
		/* All ports should be marked as ready to run again */
		zfcp_erp_modify_adapter_status(adapter,
					       ZFCP_STATUS_COMMON_RUNNING,
					       ZFCP_SET);
		zfcp_erp_adapter_reopen(adapter,
					ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED
					| ZFCP_STATUS_COMMON_ERP_FAILED);
		fsf_req->status |= ZFCP_STATUS_FSFREQ_ERROR;
		break;