aboutsummaryrefslogblamecommitdiffstats
path: root/drivers/s390/scsi/zfcp_aux.c
blob: 167fef39d8a789400d0a41968e23d64f7972ef79 (plain) (tree)
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834





















































                                                                               
                                                                            




                                                                  

                                                



                                              























                                                                               
                                  

                                                   
                                   




                                                            
























                                                                  






                                       
                               
 

                        
 
                    

                         





                                                















                                                               
                   



                                                                             
                   
























































                                                                                 



                                                            
                         

         


                                                                  






















                                                                               



















                                                                                


                                                            

































































































































































                                                                                   
                                           








                                                    
                          




























































































































































































































































































































































































                                                                                
                                              





























































































                                                                               

































































                                                                                 
                                                    

                                                    













                                                   

















































































                                                                                 
                                                              
                                                          
                                                                   





























                                                                            

                                         






















                                                                             
                               
                       

                                                          





























































                                                                        
                                                                      


















                                                                              
                                               
                                                             




















                                                                    
                        

                                                   


















































                                                                              




                                                          


                                                           


                                                           


                                                             
















                                                                              
























                                                                                    














                                                                         












                                                                             











                                                                               












                                                                            







                                                                           












                                                                              
                                                                        


                                                     
                                                 




































































































































                                                                               



                                                          









































































































































































































                                                                                
/*
 *
 * linux/drivers/s390/scsi/zfcp_aux.c
 *
 * FCP adapter driver for IBM eServer zSeries
 *
 * (C) Copyright IBM Corp. 2002, 2004
 *
 * Author(s): Martin Peschke <mpeschke@de.ibm.com>
 *            Raimund Schroeder <raimund.schroeder@de.ibm.com>
 *            Aron Zeh
 *            Wolfgang Taphorn
 *            Stefan Bader <stefan.bader@de.ibm.com>
 *            Heiko Carstens <heiko.carstens@de.ibm.com>
 *            Andreas Herrmann <aherrman@de.ibm.com>
 *
 * 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_AUX_REVISION "$Revision: 1.145 $"

#include "zfcp_ext.h"

/* accumulated log level (module parameter) */
static u32 loglevel = ZFCP_LOG_LEVEL_DEFAULTS;
static char *device;
/*********************** FUNCTION PROTOTYPES *********************************/

/* written against the module interface */
static int __init  zfcp_module_init(void);

/* FCP related */
static void zfcp_ns_gid_pn_handler(unsigned long);

/* miscellaneous */
static inline int zfcp_sg_list_alloc(struct zfcp_sg_list *, size_t);
static inline void zfcp_sg_list_free(struct zfcp_sg_list *);
static inline int zfcp_sg_list_copy_from_user(struct zfcp_sg_list *,
					      void __user *, size_t);
static inline int zfcp_sg_list_copy_to_user(void __user *,
					    struct zfcp_sg_list *, size_t);

static long zfcp_cfdc_dev_ioctl(struct file *, unsigned int, unsigned long);

#define ZFCP_CFDC_IOC_MAGIC                     0xDD
#define ZFCP_CFDC_IOC \
	_IOWR(ZFCP_CFDC_IOC_MAGIC, 0, struct zfcp_cfdc_sense_data)


static struct file_operations zfcp_cfdc_fops = {
	.unlocked_ioctl = zfcp_cfdc_dev_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl = zfcp_cfdc_dev_ioctl
#endif
};

static struct miscdevice zfcp_cfdc_misc = {
	.minor = ZFCP_CFDC_DEV_MINOR,
	.name = ZFCP_CFDC_DEV_NAME,
	.fops = &zfcp_cfdc_fops
};

/*********************** KERNEL/MODULE PARAMETERS  ***************************/

/* declare driver module init/cleanup functions */
module_init(zfcp_module_init);

MODULE_AUTHOR("Heiko Carstens <heiko.carstens@de.ibm.com>, "
	      "Andreas Herrman <aherrman@de.ibm.com>, "
	      "Martin Peschke <mpeschke@de.ibm.com>, "
	      "Raimund Schroeder <raimund.schroeder@de.ibm.com>, "
	      "Wolfgang Taphorn <taphorn@de.ibm.com>, "
	      "Aron Zeh <arzeh@de.ibm.com>, "
	      "IBM Deutschland Entwicklung GmbH");
MODULE_DESCRIPTION
    ("FCP (SCSI over Fibre Channel) HBA driver for IBM eServer zSeries");
MODULE_LICENSE("GPL");

module_param(device, charp, 0400);
MODULE_PARM_DESC(device, "specify initial device");

module_param(loglevel, uint, 0400);
MODULE_PARM_DESC(loglevel,
		 "log levels, 8 nibbles: "
		 "FC ERP QDIO CIO Config FSF SCSI Other, "
		 "levels: 0=none 1=normal 2=devel 3=trace");

/****************************************************************/
/************** Functions without logging ***********************/
/****************************************************************/

void
_zfcp_hex_dump(char *addr, int count)
{
	int i;
	for (i = 0; i < count; i++) {
		printk("%02x", addr[i]);
		if ((i % 4) == 3)
			printk(" ");
		if ((i % 32) == 31)
			printk("\n");
	}
	if (((i-1) % 32) != 31)
		printk("\n");
}

/****************************************************************/
/************** Uncategorised Functions *************************/
/****************************************************************/

#define ZFCP_LOG_AREA			ZFCP_LOG_AREA_OTHER

/**
 * zfcp_device_setup - setup function
 * @str: pointer to parameter string
 *
 * Parse "device=..." parameter string.
 */
static int __init
zfcp_device_setup(char *devstr)
{
	char *tmp, *str;
	size_t len;

	if (!devstr)
		return 0;

	len = strlen(devstr) + 1;
	str = (char *) kmalloc(len, GFP_KERNEL);
	if (!str)
		goto err_out;
	memcpy(str, devstr, len);

	tmp = strchr(str, ',');
	if (!tmp)
		goto err_out;
	*tmp++ = '\0';
	strncpy(zfcp_data.init_busid, str, BUS_ID_SIZE);
	zfcp_data.init_busid[BUS_ID_SIZE-1] = '\0';

	zfcp_data.init_wwpn = simple_strtoull(tmp, &tmp, 0);
	if (*tmp++ != ',')
		goto err_out;
	if (*tmp == '\0')
		goto err_out;

	zfcp_data.init_fcp_lun = simple_strtoull(tmp, &tmp, 0);
	if (*tmp != '\0')
		goto err_out;
	kfree(str);
	return 1;

 err_out:
	ZFCP_LOG_NORMAL("Parse error for device parameter string %s\n", str);
	kfree(str);
	return 0;
}

static void __init
zfcp_init_device_configure(void)
{
	struct zfcp_adapter *adapter;
	struct zfcp_port *port;
	struct zfcp_unit *unit;

	down(&zfcp_data.config_sema);
	read_lock_irq(&zfcp_data.config_lock);
	adapter = zfcp_get_adapter_by_busid(zfcp_data.init_busid);
	if (adapter)
		zfcp_adapter_get(adapter);
	read_unlock_irq(&zfcp_data.config_lock);

	if (adapter == NULL)
		goto out_adapter;
	port = zfcp_port_enqueue(adapter, zfcp_data.init_wwpn, 0, 0);
	if (!port)
		goto out_port;
	unit = zfcp_unit_enqueue(port, zfcp_data.init_fcp_lun);
	if (!unit)
		goto out_unit;
	up(&zfcp_data.config_sema);
	ccw_device_set_online(adapter->ccw_device);
	zfcp_erp_wait(adapter);
	down(&zfcp_data.config_sema);
	zfcp_unit_put(unit);
 out_unit:
	zfcp_port_put(port);
 out_port:
	zfcp_adapter_put(adapter);
 out_adapter:
	up(&zfcp_data.config_sema);
	return;
}

static int __init
zfcp_module_init(void)
{

	int retval = 0;

	atomic_set(&zfcp_data.loglevel, loglevel);

	/* initialize adapter list */
	INIT_LIST_HEAD(&zfcp_data.adapter_list_head);

	/* initialize adapters to be removed list head */
	INIT_LIST_HEAD(&zfcp_data.adapter_remove_lh);

	zfcp_transport_template = fc_attach_transport(&zfcp_transport_functions);
	if (!zfcp_transport_template)
		return -ENODEV;

	retval = misc_register(&zfcp_cfdc_misc);
	if (retval != 0) {
		ZFCP_LOG_INFO("registration of misc device "
			      "zfcp_cfdc failed\n");
		goto out;
	}

	ZFCP_LOG_TRACE("major/minor for zfcp_cfdc: %d/%d\n",
		       ZFCP_CFDC_DEV_MAJOR, zfcp_cfdc_misc.minor);

	/* Initialise proc semaphores */
	sema_init(&zfcp_data.config_sema, 1);

	/* initialise configuration rw lock */
	rwlock_init(&zfcp_data.config_lock);

	/* save address of data structure managing the driver module */
	zfcp_data.scsi_host_template.module = THIS_MODULE;

	/* setup dynamic I/O */
	retval = zfcp_ccw_register();
	if (retval) {
		ZFCP_LOG_NORMAL("registration with common I/O layer failed\n");
		goto out_ccw_register;
	}

	if (zfcp_device_setup(device))
		zfcp_init_device_configure();

	goto out;

 out_ccw_register:
	misc_deregister(&zfcp_cfdc_misc);
 out:
	return retval;
}

/*
 * function:    zfcp_cfdc_dev_ioctl
 *
 * purpose:     Handle control file upload/download transaction via IOCTL
 *		interface
 *
 * returns:     0           - Operation completed successfuly
 *              -ENOTTY     - Unknown IOCTL command
 *              -EINVAL     - Invalid sense data record
 *              -ENXIO      - The FCP adapter is not available
 *              -EOPNOTSUPP - The FCP adapter does not have CFDC support
 *              -ENOMEM     - Insufficient memory
 *              -EFAULT     - User space memory I/O operation fault
 *              -EPERM      - Cannot create or queue FSF request or create SBALs
 *              -ERESTARTSYS- Received signal (is mapped to EAGAIN by VFS)
 */
static long
zfcp_cfdc_dev_ioctl(struct file *file, unsigned int command,
		    unsigned long buffer)
{
	struct zfcp_cfdc_sense_data *sense_data, __user *sense_data_user;
	struct zfcp_adapter *adapter = NULL;
	struct zfcp_fsf_req *fsf_req = NULL;
	struct zfcp_sg_list *sg_list = NULL;
	u32 fsf_command, option;
	char *bus_id = NULL;
	int retval = 0;

	sense_data = kmalloc(sizeof(struct zfcp_cfdc_sense_data), GFP_KERNEL);
	if (sense_data == NULL) {
		retval = -ENOMEM;
		goto out;
	}

	sg_list = kmalloc(sizeof(struct zfcp_sg_list), GFP_KERNEL);
	if (sg_list == NULL) {
		retval = -ENOMEM;
		goto out;
	}
	memset(sg_list, 0, sizeof(*sg_list));

	if (command != ZFCP_CFDC_IOC) {
		ZFCP_LOG_INFO("IOC request code 0x%x invalid\n", command);
		retval = -ENOTTY;
		goto out;
	}

	if ((sense_data_user = (void __user *) buffer) == NULL) {
		ZFCP_LOG_INFO("sense data record is required\n");
		retval = -EINVAL;
		goto out;
	}

	retval = copy_from_user(sense_data, sense_data_user,
				sizeof(struct zfcp_cfdc_sense_data));
	if (retval) {
		retval = -EFAULT;
		goto out;
	}

	if (sense_data->signature != ZFCP_CFDC_SIGNATURE) {
		ZFCP_LOG_INFO("invalid sense data request signature 0x%08x\n",
			      ZFCP_CFDC_SIGNATURE);
		retval = -EINVAL;
		goto out;
	}

	switch (sense_data->command) {

	case ZFCP_CFDC_CMND_DOWNLOAD_NORMAL:
		fsf_command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
		option = FSF_CFDC_OPTION_NORMAL_MODE;
		break;

	case ZFCP_CFDC_CMND_DOWNLOAD_FORCE:
		fsf_command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
		option = FSF_CFDC_OPTION_FORCE;
		break;

	case ZFCP_CFDC_CMND_FULL_ACCESS:
		fsf_command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
		option = FSF_CFDC_OPTION_FULL_ACCESS;
		break;

	case ZFCP_CFDC_CMND_RESTRICTED_ACCESS:
		fsf_command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
		option = FSF_CFDC_OPTION_RESTRICTED_ACCESS;
		break;

	case ZFCP_CFDC_CMND_UPLOAD:
		fsf_command = FSF_QTCB_UPLOAD_CONTROL_FILE;
		option = 0;
		break;

	default:
		ZFCP_LOG_INFO("invalid command code 0x%08x\n",
			      sense_data->command);
		retval = -EINVAL;
		goto out;
	}

	bus_id = kmalloc(BUS_ID_SIZE, GFP_KERNEL);
	if (bus_id == NULL) {
		retval = -ENOMEM;
		goto out;
	}
	snprintf(bus_id, BUS_ID_SIZE, "%d.%d.%04x",
		(sense_data->devno >> 24),
		(sense_data->devno >> 16) & 0xFF,
		(sense_data->devno & 0xFFFF));

	read_lock_irq(&zfcp_data.config_lock);
	adapter = zfcp_get_adapter_by_busid(bus_id);
	if (adapter)
		zfcp_adapter_get(adapter);
	read_unlock_irq(&zfcp_data.config_lock);

	kfree(bus_id);

	if (adapter == NULL) {
		ZFCP_LOG_INFO("invalid adapter\n");
		retval = -ENXIO;
		goto out;
	}

	if (sense_data->command & ZFCP_CFDC_WITH_CONTROL_FILE) {
		retval = zfcp_sg_list_alloc(sg_list,
					    ZFCP_CFDC_MAX_CONTROL_FILE_SIZE);
		if (retval) {
			retval = -ENOMEM;
			goto out;
		}
	}

	if ((sense_data->command & ZFCP_CFDC_DOWNLOAD) &&
	    (sense_data->command & ZFCP_CFDC_WITH_CONTROL_FILE)) {
		retval = zfcp_sg_list_copy_from_user(
			sg_list, &sense_data_user->control_file,
			ZFCP_CFDC_MAX_CONTROL_FILE_SIZE);
		if (retval) {
			retval = -EFAULT;
			goto out;
		}
	}

	retval = zfcp_fsf_control_file(adapter, &fsf_req, fsf_command,
				       option, sg_list);
	if (retval)
		goto out;

	if ((fsf_req->qtcb->prefix.prot_status != FSF_PROT_GOOD) &&
	    (fsf_req->qtcb->prefix.prot_status != FSF_PROT_FSF_STATUS_PRESENTED)) {
		retval = -ENXIO;
		goto out;
	}

	sense_data->fsf_status = fsf_req->qtcb->header.fsf_status;
	memcpy(&sense_data->fsf_status_qual,
	       &fsf_req->qtcb->header.fsf_status_qual,
	       sizeof(union fsf_status_qual));
	memcpy(&sense_data->payloads, &fsf_req->qtcb->bottom.support.els, 256);

	retval = copy_to_user(sense_data_user, sense_data,
		sizeof(struct zfcp_cfdc_sense_data));
	if (retval) {
		retval = -EFAULT;
		goto out;
	}

	if (sense_data->command & ZFCP_CFDC_UPLOAD) {
		retval = zfcp_sg_list_copy_to_user(
			&sense_data_user->control_file, sg_list,
			ZFCP_CFDC_MAX_CONTROL_FILE_SIZE);
		if (retval) {
			retval = -EFAULT;
			goto out;
		}
	}

 out:
	if (fsf_req != NULL)
		zfcp_fsf_req_free(fsf_req);

	if ((adapter != NULL) && (retval != -ENXIO))
		zfcp_adapter_put(adapter);

	if (sg_list != NULL) {
		zfcp_sg_list_free(sg_list);
		kfree(sg_list);
	}

	kfree(sense_data);

	return retval;
}


/**
 * zfcp_sg_list_alloc - create a scatter-gather list of the specified size
 * @sg_list: structure describing a scatter gather list
 * @size: size of scatter-gather list
 * Return: 0 on success, else -ENOMEM
 *
 * In sg_list->sg a pointer to the created scatter-gather list is returned,
 * or NULL if we run out of memory. sg_list->count specifies the number of
 * elements of the scatter-gather list. The maximum size of a single element
 * in the scatter-gather list is PAGE_SIZE.
 */
static inline int
zfcp_sg_list_alloc(struct zfcp_sg_list *sg_list, size_t size)
{
	struct scatterlist *sg;
	unsigned int i;
	int retval = 0;
	void *address;

	BUG_ON(sg_list == NULL);

	sg_list->count = size >> PAGE_SHIFT;
	if (size & ~PAGE_MASK)
		sg_list->count++;
	sg_list->sg = kmalloc(sg_list->count * sizeof(struct scatterlist),
			      GFP_KERNEL);
	if (sg_list->sg == NULL) {
		sg_list->count = 0;
		retval = -ENOMEM;
		goto out;
	}
	memset(sg_list->sg, 0, sg_list->count * sizeof(struct scatterlist));

	for (i = 0, sg = sg_list->sg; i < sg_list->count; i++, sg++) {
		sg->length = min(size, PAGE_SIZE);
		sg->offset = 0;
		address = (void *) get_zeroed_page(GFP_KERNEL);
		if (address == NULL) {
			sg_list->count = i;
			zfcp_sg_list_free(sg_list);
			retval = -ENOMEM;
			goto out;
		}
		zfcp_address_to_sg(address, sg);
		size -= sg->length;
	}

 out:
	return retval;
}


/**
 * zfcp_sg_list_free - free memory of a scatter-gather list
 * @sg_list: structure describing a scatter-gather list
 *
 * Memory for each element in the scatter-gather list is freed.
 * Finally sg_list->sg is freed itself and sg_list->count is reset.
 */
static inline void
zfcp_sg_list_free(struct zfcp_sg_list *sg_list)
{
	struct scatterlist *sg;
	unsigned int i;

	BUG_ON(sg_list == NULL);

	for (i = 0, sg = sg_list->sg; i < sg_list->count; i++, sg++)
		free_page((unsigned long) zfcp_sg_to_address(sg));

	sg_list->count = 0;
	kfree(sg_list->sg);
}

/**
 * zfcp_sg_size - determine size of a scatter-gather list
 * @sg: array of (struct scatterlist)
 * @sg_count: elements in array
 * Return: size of entire scatter-gather list
 */
size_t
zfcp_sg_size(struct scatterlist *sg, unsigned int sg_count)
{
	unsigned int i;
	struct scatterlist *p;
	size_t size;

	size = 0;
	for (i = 0, p = sg; i < sg_count; i++, p++) {
		BUG_ON(p == NULL);
		size += p->length;
	}

	return size;
}


/**
 * zfcp_sg_list_copy_from_user -copy data from user space to scatter-gather list
 * @sg_list: structure describing a scatter-gather list
 * @user_buffer: pointer to buffer in user space
 * @size: number of bytes to be copied
 * Return: 0 on success, -EFAULT if copy_from_user fails.
 */
static inline int
zfcp_sg_list_copy_from_user(struct zfcp_sg_list *sg_list,
			    void __user *user_buffer,
                            size_t size)
{
	struct scatterlist *sg;
	unsigned int length;
	void *zfcp_buffer;
	int retval = 0;

	BUG_ON(sg_list == NULL);

	if (zfcp_sg_size(sg_list->sg, sg_list->count) < size)
		return -EFAULT;

	for (sg = sg_list->sg; size > 0; sg++) {
		length = min((unsigned int)size, sg->length);
		zfcp_buffer = zfcp_sg_to_address(sg);
		if (copy_from_user(zfcp_buffer, user_buffer, length)) {
			retval = -EFAULT;
			goto out;
		}
		user_buffer += length;
		size -= length;
	}

 out:
	return retval;
}


/**
 * zfcp_sg_list_copy_to_user - copy data from scatter-gather list to user space
 * @user_buffer: pointer to buffer in user space
 * @sg_list: structure describing a scatter-gather list
 * @size: number of bytes to be copied
 * Return: 0 on success, -EFAULT if copy_to_user fails
 */
static inline int
zfcp_sg_list_copy_to_user(void __user  *user_buffer,
			  struct zfcp_sg_list *sg_list,
                          size_t size)
{
	struct scatterlist *sg;
	unsigned int length;
	void *zfcp_buffer;
	int retval = 0;

	BUG_ON(sg_list == NULL);

	if (zfcp_sg_size(sg_list->sg, sg_list->count) < size)
		return -EFAULT;

	for (sg = sg_list->sg; size > 0; sg++) {
		length = min((unsigned int) size, sg->length);
		zfcp_buffer = zfcp_sg_to_address(sg);
		if (copy_to_user(user_buffer, zfcp_buffer, length)) {
			retval = -EFAULT;
			goto out;
		}
		user_buffer += length;
		size -= length;
	}

 out:
	return retval;
}


#undef ZFCP_LOG_AREA

/****************************************************************/
/****** Functions for configuration/set-up of structures ********/
/****************************************************************/

#define ZFCP_LOG_AREA			ZFCP_LOG_AREA_CONFIG

/**
 * zfcp_get_unit_by_lun - find unit in unit list of port by FCP LUN
 * @port: pointer to port to search for unit
 * @fcp_lun: FCP LUN to search for
 * Traverse list of all units of a port and return pointer to a unit
 * with the given FCP LUN.
 */
struct zfcp_unit *
zfcp_get_unit_by_lun(struct zfcp_port *port, fcp_lun_t fcp_lun)
{
	struct zfcp_unit *unit;
	int found = 0;

	list_for_each_entry(unit, &port->unit_list_head, list) {
		if ((unit->fcp_lun == fcp_lun) &&
		    !atomic_test_mask(ZFCP_STATUS_COMMON_REMOVE, &unit->status))
		{
			found = 1;
			break;
		}
	}
	return found ? unit : NULL;
}

/**
 * zfcp_get_port_by_wwpn - find port in port list of adapter by wwpn
 * @adapter: pointer to adapter to search for port
 * @wwpn: wwpn to search for
 * Traverse list of all ports of an adapter and return pointer to a port
 * with the given wwpn.
 */
struct zfcp_port *
zfcp_get_port_by_wwpn(struct zfcp_adapter *adapter, wwn_t wwpn)
{
	struct zfcp_port *port;
	int found = 0;

	list_for_each_entry(port, &adapter->port_list_head, list) {
		if ((port->wwpn == wwpn) &&
		    !(atomic_read(&port->status) &
		      (ZFCP_STATUS_PORT_NO_WWPN | ZFCP_STATUS_COMMON_REMOVE))) {
			found = 1;
			break;
		}
	}
	return found ? port : NULL;
}

/**
 * zfcp_get_port_by_did - find port in port list of adapter by d_id
 * @adapter: pointer to adapter to search for port
 * @d_id: d_id to search for
 * Traverse list of all ports of an adapter and return pointer to a port
 * with the given d_id.
 */
struct zfcp_port *
zfcp_get_port_by_did(struct zfcp_adapter *adapter, u32 d_id)
{
	struct zfcp_port *port;
	int found = 0;

	list_for_each_entry(port, &adapter->port_list_head, list) {
		if ((port->d_id == d_id) &&
		    !atomic_test_mask(ZFCP_STATUS_COMMON_REMOVE, &port->status))
		{
			found = 1;
			break;
		}
	}
	return found ? port : NULL;
}

/**
 * zfcp_get_adapter_by_busid - find adpater in adapter list by bus_id
 * @bus_id: bus_id to search for
 * Traverse list of all adapters and return pointer to an adapter
 * with the given bus_id.
 */
struct zfcp_adapter *
zfcp_get_adapter_by_busid(char *bus_id)
{
	struct zfcp_adapter *adapter;
	int found = 0;

	list_for_each_entry(adapter, &zfcp_data.adapter_list_head, list) {
		if ((strncmp(bus_id, zfcp_get_busid_by_adapter(adapter),
			     BUS_ID_SIZE) == 0) &&
		    !atomic_test_mask(ZFCP_STATUS_COMMON_REMOVE,
				      &adapter->status)){
			found = 1;
			break;
		}
	}
	return found ? adapter : NULL;
}

/**
 * zfcp_unit_enqueue - enqueue unit to unit list of a port.
 * @port: pointer to port where unit is added
 * @fcp_lun: FCP LUN of unit to be enqueued
 * Return: pointer to enqueued unit on success, NULL on error
 * Locks: config_sema must be held to serialize changes to the unit list
 *
 * Sets up some unit internal structures and creates sysfs entry.
 */
struct zfcp_unit *
zfcp_unit_enqueue(struct zfcp_port *port, fcp_lun_t fcp_lun)
{
	struct zfcp_unit *unit, *tmp_unit;
	scsi_lun_t scsi_lun;
	int found;

	/*
	 * check that there is no unit with this FCP_LUN already in list
	 * and enqueue it.
	 * Note: Unlike for the adapter and the port, this is an error
	 */
	read_lock_irq(&zfcp_data.config_lock);
	unit = zfcp_get_unit_by_lun(port, fcp_lun);
	read_unlock_irq(&zfcp_data.config_lock);
	if (unit)
		return NULL;

	unit = kmalloc(sizeof (struct zfcp_unit), GFP_KERNEL);
	if (!unit)
		return NULL;
	memset(unit, 0, sizeof (struct zfcp_unit));

	/* initialise reference count stuff */
	atomic_set(&unit->refcount, 0);
	init_waitqueue_head(&unit->remove_wq);

	unit->port = port;
	unit->fcp_lun = fcp_lun;

	/* setup for sysfs registration */
	snprintf(unit->sysfs_device.bus_id, BUS_ID_SIZE, "0x%016llx", fcp_lun);
	unit->sysfs_device.parent = &port->sysfs_device;
	unit->sysfs_device.release = zfcp_sysfs_unit_release;
	dev_set_drvdata(&unit->sysfs_device, unit);

	/* mark unit unusable as long as sysfs registration is not complete */
	atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &unit->status);

	if (device_register(&unit->sysfs_device)) {
		kfree(unit);
		return NULL;
	}

	if (zfcp_sysfs_unit_create_files(&unit->sysfs_device)) {
		device_unregister(&unit->sysfs_device);
		return NULL;
	}

	zfcp_unit_get(unit);

	scsi_lun = 0;
	found = 0;
	write_lock_irq(&zfcp_data.config_lock);
	list_for_each_entry(tmp_unit, &port->unit_list_head, list) {
		if (tmp_unit->scsi_lun != scsi_lun) {
			found = 1;
			break;
		}
		scsi_lun++;
	}
	unit->scsi_lun = scsi_lun;
	if (found)
		list_add_tail(&unit->list, &tmp_unit->list);
	else
		list_add_tail(&unit->list, &port->unit_list_head);
	atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &unit->status);
	atomic_set_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status);
	write_unlock_irq(&zfcp_data.config_lock);

	port->units++;
	zfcp_port_get(port);

	return unit;
}

void
zfcp_unit_dequeue(struct zfcp_unit *unit)
{
	zfcp_unit_wait(unit);
	write_lock_irq(&zfcp_data.config_lock);
	list_del(&unit->list);
	write_unlock_irq(&zfcp_data.config_lock);
	unit->port->units--;
	zfcp_port_put(unit->port);
	zfcp_sysfs_unit_remove_files(&unit->sysfs_device);
	device_unregister(&unit->sysfs_device);
}

static void *
zfcp_mempool_alloc(gfp_t gfp_mask, void *size)
{
	return kmalloc((size_t) size, gfp_mask);
}

static void
zfcp_mempool_free(void *element, void *size)
{
	kfree(element);
}

/*
 * Allocates a combined QTCB/fsf_req buffer for erp actions and fcp/SCSI
 * commands.
 * It also genrates fcp-nameserver request/response buffer and unsolicited 
 * status read fsf_req buffers.
 *
 * locks:       must only be called with zfcp_data.config_sema taken
 */
static int
zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
{
	adapter->pool.fsf_req_erp =
		mempool_create(ZFCP_POOL_FSF_REQ_ERP_NR,
			       zfcp_mempool_alloc, zfcp_mempool_free, (void *)
			       sizeof(struct zfcp_fsf_req_pool_element));

	if (NULL == adapter->pool.fsf_req_erp)
		return -ENOMEM;

	adapter->pool.fsf_req_scsi =
		mempool_create(ZFCP_POOL_FSF_REQ_SCSI_NR,
			       zfcp_mempool_alloc, zfcp_mempool_free, (void *)
			       sizeof(struct zfcp_fsf_req_pool_element));

	if (NULL == adapter->pool.fsf_req_scsi)
		return -ENOMEM;

	adapter->pool.fsf_req_abort =
		mempool_create(ZFCP_POOL_FSF_REQ_ABORT_NR,
			       zfcp_mempool_alloc, zfcp_mempool_free, (void *)
			       sizeof(struct zfcp_fsf_req_pool_element));

	if (NULL == adapter->pool.fsf_req_abort)
		return -ENOMEM;

	adapter->pool.fsf_req_status_read =
		mempool_create(ZFCP_POOL_STATUS_READ_NR,
			       zfcp_mempool_alloc, zfcp_mempool_free,
			       (void *) sizeof(struct zfcp_fsf_req));

	if (NULL == adapter->pool.fsf_req_status_read)
		return -ENOMEM;

	adapter->pool.data_status_read =
		mempool_create(ZFCP_POOL_STATUS_READ_NR,
			       zfcp_mempool_alloc, zfcp_mempool_free,
			       (void *) sizeof(struct fsf_status_read_buffer));

	if (NULL == adapter->pool.data_status_read)
		return -ENOMEM;

	adapter->pool.data_gid_pn =
		mempool_create(ZFCP_POOL_DATA_GID_PN_NR,
			       zfcp_mempool_alloc, zfcp_mempool_free, (void *)
			       sizeof(struct zfcp_gid_pn_data));

	if (NULL == adapter->pool.data_gid_pn)
		return -ENOMEM;

	return 0;
}

/**
 * zfcp_free_low_mem_buffers - free memory pools of an adapter
 * @adapter: pointer to zfcp_adapter for which memory pools should be freed
 * locking:  zfcp_data.config_sema must be held
 */
static void
zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
{
	if (adapter->pool.fsf_req_erp)
		mempool_destroy(adapter->pool.fsf_req_erp);
	if (adapter->pool.fsf_req_scsi)
		mempool_destroy(adapter->pool.fsf_req_scsi);
	if (adapter->pool.fsf_req_abort)
		mempool_destroy(adapter->pool.fsf_req_abort);
	if (adapter->pool.fsf_req_status_read)
		mempool_destroy(adapter->pool.fsf_req_status_read);
	if (adapter->pool.data_status_read)
		mempool_destroy(adapter->pool.data_status_read);
	if (adapter->pool.data_gid_pn)
		mempool_destroy(adapter->pool.data_gid_pn);
}

void
zfcp_dummy_release(struct device *dev)
{
	return;
}

/*
 * Enqueues an adapter at the end of the adapter list in the driver data.
 * All adapter internal structures are set up.
 * Proc-fs entries are also created.
 *
 * returns:	0             if a new adapter was successfully enqueued
 *              ZFCP_KNOWN    if an adapter with this devno was already present
 *		-ENOMEM       if alloc failed
 * locks:	config_sema must be held to serialise changes to the adapter list
 */
struct zfcp_adapter *
zfcp_adapter_enqueue(struct ccw_device *ccw_device)
{
	int retval = 0;
	struct zfcp_adapter *adapter;

	/*
	 * Note: It is safe to release the list_lock, as any list changes 
	 * are protected by the config_sema, which must be held to get here
	 */

	/* try to allocate new adapter data structure (zeroed) */
	adapter = kmalloc(sizeof (struct zfcp_adapter), GFP_KERNEL);
	if (!adapter) {
		ZFCP_LOG_INFO("error: allocation of base adapter "
			      "structure failed\n");
		goto out;
	}
	memset(adapter, 0, sizeof (struct zfcp_adapter));

	ccw_device->handler = NULL;

	/* save ccw_device pointer */
	adapter->ccw_device = ccw_device;

	retval = zfcp_qdio_allocate_queues(adapter);
	if (retval)
		goto queues_alloc_failed;

	retval = zfcp_qdio_allocate(adapter);
	if (retval)
		goto qdio_allocate_failed;

	retval = zfcp_allocate_low_mem_buffers(adapter);
	if (retval) {
		ZFCP_LOG_INFO("error: pool allocation failed\n");
		goto failed_low_mem_buffers;
	}

	/* initialise reference count stuff */
	atomic_set(&adapter->refcount, 0);
	init_waitqueue_head(&adapter->remove_wq);

	/* initialise list of ports */
	INIT_LIST_HEAD(&adapter->port_list_head);

	/* initialise list of ports to be removed */
	INIT_LIST_HEAD(&adapter->port_remove_lh);

	/* initialize list of fsf requests */
	spin_lock_init(&adapter->fsf_req_list_lock);
	INIT_LIST_HEAD(&adapter->fsf_req_list_head);

	/* initialize debug locks */

	spin_lock_init(&adapter->erp_dbf_lock);
	spin_lock_init(&adapter->hba_dbf_lock);
	spin_lock_init(&adapter->san_dbf_lock);
	spin_lock_init(&adapter->scsi_dbf_lock);

	/* initialize error recovery stuff */

	rwlock_init(&adapter->erp_lock);
	sema_init(&adapter->erp_ready_sem, 0);
	INIT_LIST_HEAD(&adapter->erp_ready_head);
	INIT_LIST_HEAD(&adapter->erp_running_head);

	/* initialize abort lock */
	rwlock_init(&adapter->abort_lock);

	/* initialise some erp stuff */
	init_waitqueue_head(&adapter->erp_thread_wqh);
	init_waitqueue_head(&adapter->erp_done_wqh);

	/* initialize lock of associated request queue */
	rwlock_init(&adapter->request_queue.queue_lock);

	/* intitialise SCSI ER timer */
	init_timer(&adapter->scsi_er_timer);

	/* set FC service class used per default */
	adapter->fc_service_class = ZFCP_FC_SERVICE_CLASS_DEFAULT;

	sprintf(adapter->name, "%s", zfcp_get_busid_by_adapter(adapter));
	ASCEBC(adapter->name, strlen(adapter->name));

	/* mark adapter unusable as long as sysfs registration is not complete */
	atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);

	adapter->ccw_device = ccw_device;
	dev_set_drvdata(&ccw_device->dev, adapter);

	if (zfcp_sysfs_adapter_create_files(&ccw_device->dev))
		goto sysfs_failed;

	adapter->generic_services.parent = &adapter->ccw_device->dev;
	adapter->generic_services.release = zfcp_dummy_release;
	snprintf(adapter->generic_services.bus_id, BUS_ID_SIZE,
		 "generic_services");

	if (device_register(&adapter->generic_services))
		goto generic_services_failed;

	/* put allocated adapter at list tail */
	write_lock_irq(&zfcp_data.config_lock);
	atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);
	list_add_tail(&adapter->list, &zfcp_data.adapter_list_head);
	write_unlock_irq(&zfcp_data.config_lock);

	zfcp_data.adapters++;

	goto out;

 generic_services_failed:
	zfcp_sysfs_adapter_remove_files(&adapter->ccw_device->dev);
 sysfs_failed:
	dev_set_drvdata(&ccw_device->dev, NULL);
 failed_low_mem_buffers:
	zfcp_free_low_mem_buffers(adapter);
	if (qdio_free(ccw_device) != 0)
		ZFCP_LOG_NORMAL("bug: qdio_free for adapter %s failed\n",
				zfcp_get_busid_by_adapter(adapter));
 qdio_allocate_failed:
	zfcp_qdio_free_queues(adapter);
 queues_alloc_failed:
	kfree(adapter);
	adapter = NULL;
 out:
	return adapter;
}

/*
 * returns:	0 - struct zfcp_adapter  data structure successfully removed
 *		!0 - struct zfcp_adapter  data structure could not be removed
 *			(e.g. still used)
 * locks:	adapter list write lock is assumed to be held by caller
 *              adapter->fsf_req_list_lock is taken and released within this 
 *              function and must not be held on entry
 */
void
zfcp_adapter_dequeue(struct zfcp_adapter *adapter)
{
	int retval = 0;
	unsigned long flags;

	device_unregister(&adapter->generic_services);
	zfcp_sysfs_adapter_remove_files(&adapter->ccw_device->dev);
	dev_set_drvdata(&adapter->ccw_device->dev, NULL);
	/* sanity check: no pending FSF requests */
	spin_lock_irqsave(&adapter->fsf_req_list_lock, flags);
	retval = !list_empty(&adapter->fsf_req_list_head);
	spin_unlock_irqrestore(&adapter->fsf_req_list_lock, flags);
	if (retval) {
		ZFCP_LOG_NORMAL("bug: adapter %s (%p) still in use, "
				"%i requests outstanding\n",
				zfcp_get_busid_by_adapter(adapter), adapter,
				atomic_read(&adapter->fsf_reqs_active));
		retval = -EBUSY;
		goto out;
	}

	/* remove specified adapter data structure from list */
	write_lock_irq(&zfcp_data.config_lock);
	list_del(&adapter->list);
	write_unlock_irq(&zfcp_data.config_lock);

	/* decrease number of adapters in list */
	zfcp_data.adapters--;

	ZFCP_LOG_TRACE("adapter %s (%p) removed from list, "
		       "%i adapters still in list\n",
		       zfcp_get_busid_by_adapter(adapter),
		       adapter, zfcp_data.adapters);

	retval = qdio_free(adapter->ccw_device);
	if (retval)
		ZFCP_LOG_NORMAL("bug: qdio_free for adapter %s failed\n",
				zfcp_get_busid_by_adapter(adapter));

	zfcp_free_low_mem_buffers(adapter);
	/* free memory of adapter data structure and queues */
	zfcp_qdio_free_queues(adapter);
	kfree(adapter->fc_stats);
	kfree(adapter->stats_reset_data);
	ZFCP_LOG_TRACE("freeing adapter structure\n");
	kfree(adapter);
 out:
	return;
}

/**
 * zfcp_port_enqueue - enqueue port to port list of adapter
 * @adapter: adapter where remote port is added
 * @wwpn: WWPN of the remote port to be enqueued
 * @status: initial status for the port
 * @d_id: destination id of the remote port to be enqueued
 * Return: pointer to enqueued port on success, NULL on error
 * Locks: config_sema must be held to serialize changes to the port list
 *
 * All port internal structures are set up and the sysfs entry is generated.
 * d_id is used to enqueue ports with a well known address like the Directory
 * Service for nameserver lookup.
 */
struct zfcp_port *
zfcp_port_enqueue(struct zfcp_adapter *adapter, wwn_t wwpn, u32 status,
		  u32 d_id)
{
	struct zfcp_port *port;
	int check_wwpn;

	check_wwpn = !(status & ZFCP_STATUS_PORT_NO_WWPN);
	/*
	 * check that there is no port with this WWPN already in list
	 */
	if (check_wwpn) {
		read_lock_irq(&zfcp_data.config_lock);
		port = zfcp_get_port_by_wwpn(adapter, wwpn);
		read_unlock_irq(&zfcp_data.config_lock);
		if (port)
			return NULL;
	}

	port = kmalloc(sizeof (struct zfcp_port), GFP_KERNEL);
	if (!port)
		return NULL;
	memset(port, 0, sizeof (struct zfcp_port));

	/* initialise reference count stuff */
	atomic_set(&port->refcount, 0);
	init_waitqueue_head(&port->remove_wq);

	INIT_LIST_HEAD(&port->unit_list_head);
	INIT_LIST_HEAD(&port->unit_remove_lh);

	port->adapter = adapter;

	if (check_wwpn)
		port->wwpn = wwpn;

	atomic_set_mask(status, &port->status);

	/* setup for sysfs registration */
	if (status & ZFCP_STATUS_PORT_WKA) {
		switch (d_id) {
		case ZFCP_DID_DIRECTORY_SERVICE:
			snprintf(port->sysfs_device.bus_id, BUS_ID_SIZE,
				 "directory");
			break;
		case ZFCP_DID_MANAGEMENT_SERVICE:
			snprintf(port->sysfs_device.bus_id, BUS_ID_SIZE,
				 "management");
			break;
		case ZFCP_DID_KEY_DISTRIBUTION_SERVICE:
			snprintf(port->sysfs_device.bus_id, BUS_ID_SIZE,
				 "key_distribution");
			break;
		case ZFCP_DID_ALIAS_SERVICE:
			snprintf(port->sysfs_device.bus_id, BUS_ID_SIZE,
				 "alias");
			break;
		case ZFCP_DID_TIME_SERVICE:
			snprintf(port->sysfs_device.bus_id, BUS_ID_SIZE,
				 "time");
			break;
		default:
			kfree(port);
			return NULL;
		}
		port->d_id = d_id;
		port->sysfs_device.parent = &adapter->generic_services;
	} else {
		snprintf(port->sysfs_device.bus_id,
			 BUS_ID_SIZE, "0x%016llx", wwpn);
		port->sysfs_device.parent = &adapter->ccw_device->dev;
	}
	port->sysfs_device.release = zfcp_sysfs_port_release;
	dev_set_drvdata(&port->sysfs_device, port);

	/* mark port unusable as long as sysfs registration is not complete */
	atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &port->status);

	if (device_register(&port->sysfs_device)) {
		kfree(port);
		return NULL;
	}

	if (zfcp_sysfs_port_create_files(&port->sysfs_device, status)) {
		device_unregister(&port->sysfs_device);
		return NULL;
	}

	zfcp_port_get(port);

	write_lock_irq(&zfcp_data.config_lock);
	list_add_tail(&port->list, &adapter->port_list_head);
	atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &port->status);
	atomic_set_mask(ZFCP_STATUS_COMMON_RUNNING, &port->status);
	if (d_id == ZFCP_DID_DIRECTORY_SERVICE)
		if (!adapter->nameserver_port)
			adapter->nameserver_port = port;
	adapter->ports++;
	write_unlock_irq(&zfcp_data.config_lock);

	zfcp_adapter_get(adapter);

	return port;
}

void
zfcp_port_dequeue(struct zfcp_port *port)
{
	zfcp_port_wait(port);
	write_lock_irq(&zfcp_data.config_lock);
	list_del(&port->list);
	port->adapter->ports--;
	write_unlock_irq(&zfcp_data.config_lock);
	if (port->rport)
		fc_remote_port_delete(port->rport);
	port->rport = NULL;
	zfcp_adapter_put(port->adapter);
	zfcp_sysfs_port_remove_files(&port->sysfs_device,
				     atomic_read(&port->status));
	device_unregister(&port->sysfs_device);
}

/* Enqueues a nameserver port */
int
zfcp_nameserver_enqueue(struct zfcp_adapter *adapter)
{
	struct zfcp_port *port;

	port = zfcp_port_enqueue(adapter, 0, ZFCP_STATUS_PORT_WKA,
				 ZFCP_DID_DIRECTORY_SERVICE);
	if (!port) {
		ZFCP_LOG_INFO("error: enqueue of nameserver port for "
			      "adapter %s failed\n",
			      zfcp_get_busid_by_adapter(adapter));
		return -ENXIO;
	}
	zfcp_port_put(port);

	return 0;
}

#undef ZFCP_LOG_AREA

/****************************************************************/
/******* Fibre Channel Standard related Functions  **************/
/****************************************************************/

#define ZFCP_LOG_AREA                   ZFCP_LOG_AREA_FC

void
zfcp_fsf_incoming_els_rscn(struct zfcp_adapter *adapter,
			   struct fsf_status_read_buffer *status_buffer)
{
	struct fcp_rscn_head *fcp_rscn_head;
	struct fcp_rscn_element *fcp_rscn_element;
	struct zfcp_port *port;
	u16 i;
	u16 no_entries;
	u32 range_mask;
	unsigned long flags;

	fcp_rscn_head = (struct fcp_rscn_head *) status_buffer->payload;
	fcp_rscn_element = (struct fcp_rscn_element *) status_buffer->payload;

	/* see FC-FS */
	no_entries = (fcp_rscn_head->payload_len / 4);

	for (i = 1; i < no_entries; i++) {
		/* skip head and start with 1st element */
		fcp_rscn_element++;
		switch (fcp_rscn_element->addr_format) {
		case ZFCP_PORT_ADDRESS:
			range_mask = ZFCP_PORTS_RANGE_PORT;
			break;
		case ZFCP_AREA_ADDRESS:
			range_mask = ZFCP_PORTS_RANGE_AREA;
			break;
		case ZFCP_DOMAIN_ADDRESS:
			range_mask = ZFCP_PORTS_RANGE_DOMAIN;
			break;
		case ZFCP_FABRIC_ADDRESS:
			range_mask = ZFCP_PORTS_RANGE_FABRIC;
			break;
		default:
			ZFCP_LOG_INFO("incoming RSCN with unknown "
				      "address format\n");
			continue;
		}
		read_lock_irqsave(&zfcp_data.config_lock, flags);
		list_for_each_entry(port, &adapter->port_list_head, list) {
			if (atomic_test_mask
			    (ZFCP_STATUS_PORT_WKA, &port->status))
				continue;
			/* Do we know this port? If not skip it. */
			if (!atomic_test_mask
			    (ZFCP_STATUS_PORT_DID_DID, &port->status)) {
				ZFCP_LOG_INFO("incoming RSCN, trying to open "
					      "port 0x%016Lx\n", port->wwpn);
				zfcp_erp_port_reopen(port,
						     ZFCP_STATUS_COMMON_ERP_FAILED);
				continue;
			}

			/*
			 * FIXME: race: d_id might being invalidated
			 * (...DID_DID reset)
			 */
			if ((port->d_id & range_mask)
			    == (fcp_rscn_element->nport_did & range_mask)) {
				ZFCP_LOG_TRACE("reopen did 0x%08x\n",
					       fcp_rscn_element->nport_did);
				/*
				 * Unfortunately, an RSCN does not specify the
				 * type of change a target underwent. We assume
				 * that it makes sense to reopen the link.
				 * FIXME: Shall we try to find out more about
				 * the target and link state before closing it?
				 * How to accomplish this? (nameserver?)
				 * Where would such code be put in?
				 * (inside or outside erp)
				 */
				ZFCP_LOG_INFO("incoming RSCN, trying to open "
					      "port 0x%016Lx\n", port->wwpn);
				zfcp_test_link(port);
			}
		}
		read_unlock_irqrestore(&zfcp_data.config_lock, flags);
	}
}

static void
zfcp_fsf_incoming_els_plogi(struct zfcp_adapter *adapter,
			    struct fsf_status_read_buffer *status_buffer)
{
	logi *els_logi = (logi *) status_buffer->payload;
	struct zfcp_port *port;
	unsigned long flags;

	read_lock_irqsave(&zfcp_data.config_lock, flags);
	list_for_each_entry(port, &adapter->port_list_head, list) {
		if (port->wwpn == (*(wwn_t *) & els_logi->nport_wwn))
			break;
	}
	read_unlock_irqrestore(&zfcp_data.config_lock, flags);

	if (!port || (port->wwpn != (*(wwn_t *) & els_logi->nport_wwn))) {
		ZFCP_LOG_DEBUG("ignored incoming PLOGI for nonexisting port "
			       "with d_id 0x%08x on adapter %s\n",
			       status_buffer->d_id,
			       zfcp_get_busid_by_adapter(adapter));
	} else {
		zfcp_erp_port_forced_reopen(port, 0);
	}
}

static void
zfcp_fsf_incoming_els_logo(struct zfcp_adapter *adapter,
			   struct fsf_status_read_buffer *status_buffer)
{
	struct fcp_logo *els_logo = (struct fcp_logo *) status_buffer->payload;
	struct zfcp_port *port;
	unsigned long flags;

	read_lock_irqsave(&zfcp_data.config_lock, flags);
	list_for_each_entry(port, &adapter->port_list_head, list) {
		if (port->wwpn == els_logo->nport_wwpn)
			break;
	}
	read_unlock_irqrestore(&zfcp_data.config_lock, flags);

	if (!port || (port->wwpn != els_logo->nport_wwpn)) {
		ZFCP_LOG_DEBUG("ignored incoming LOGO for nonexisting port "
			       "with d_id 0x%08x on adapter %s\n",
			       status_buffer->d_id,
			       zfcp_get_busid_by_adapter(adapter));
	} else {
		zfcp_erp_port_forced_reopen(port, 0);
	}
}

static void
zfcp_fsf_incoming_els_unknown(struct zfcp_adapter *adapter,
			      struct fsf_status_read_buffer *status_buffer)
{
	ZFCP_LOG_NORMAL("warning: unknown incoming ELS 0x%08x "
			"for adapter %s\n", *(u32 *) (status_buffer->payload),
			zfcp_get_busid_by_adapter(adapter));

}

void
zfcp_fsf_incoming_els(struct zfcp_fsf_req *fsf_req)
{
	struct fsf_status_read_buffer *status_buffer;
	u32 els_type;
	struct zfcp_adapter *adapter;

	status_buffer = (struct fsf_status_read_buffer *) fsf_req->data;
	els_type = *(u32 *) (status_buffer->payload);
	adapter = fsf_req->adapter;

	zfcp_san_dbf_event_incoming_els(fsf_req);
	if (els_type == LS_PLOGI)
		zfcp_fsf_incoming_els_plogi(adapter, status_buffer);
	else if (els_type == LS_LOGO)
		zfcp_fsf_incoming_els_logo(adapter, status_buffer);
	else if ((els_type & 0xffff0000) == LS_RSCN)
		/* we are only concerned with the command, not the length */
		zfcp_fsf_incoming_els_rscn(adapter, status_buffer);
	else
		zfcp_fsf_incoming_els_unknown(adapter, status_buffer);
}


/**
 * zfcp_gid_pn_buffers_alloc - allocate buffers for GID_PN nameserver request
 * @gid_pn: pointer to return pointer to struct zfcp_gid_pn_data
 * @pool: pointer to mempool_t if non-null memory pool is used for allocation
 */
static int
zfcp_gid_pn_buffers_alloc(struct zfcp_gid_pn_data **gid_pn, mempool_t *pool)
{
	struct zfcp_gid_pn_data *data;

	if (pool != NULL) {
		data = mempool_alloc(pool, GFP_ATOMIC);
		if (likely(data != NULL)) {
			data->ct.pool = pool;
		}
	} else {
		data = kmalloc(sizeof(struct zfcp_gid_pn_data), GFP_ATOMIC);
	}

        if (NULL == data)
                return -ENOMEM;

	memset(data, 0, sizeof(*data));
        data->ct.req = &data->req;
        data->ct.resp = &data->resp;
	data->ct.req_count = data->ct.resp_count = 1;
	zfcp_address_to_sg(&data->ct_iu_req, &data->req);
        zfcp_address_to_sg(&data->ct_iu_resp, &data->resp);
        data->req.length = sizeof(struct ct_iu_gid_pn_req);
        data->resp.length = sizeof(struct ct_iu_gid_pn_resp);

	*gid_pn = data;
	return 0;
}

/**
 * zfcp_gid_pn_buffers_free - free buffers for GID_PN nameserver request
 * @gid_pn: pointer to struct zfcp_gid_pn_data which has to be freed
 */
static void
zfcp_gid_pn_buffers_free(struct zfcp_gid_pn_data *gid_pn)
{
        if ((gid_pn->ct.pool != 0))
		mempool_free(gid_pn, gid_pn->ct.pool);
	else
                kfree(gid_pn);

	return;
}

/**
 * zfcp_ns_gid_pn_request - initiate GID_PN nameserver request
 * @erp_action: pointer to zfcp_erp_action where GID_PN request is needed
 */
int
zfcp_ns_gid_pn_request(struct zfcp_erp_action *erp_action)
{
	int ret;
        struct ct_iu_gid_pn_req *ct_iu_req;
        struct zfcp_gid_pn_data *gid_pn;
        struct zfcp_adapter *adapter = erp_action->adapter;

	ret = zfcp_gid_pn_buffers_alloc(&gid_pn, adapter->pool.data_gid_pn);
	if (ret < 0) {
		ZFCP_LOG_INFO("error: buffer allocation for gid_pn nameserver "
			      "request failed for adapter %s\n",
			      zfcp_get_busid_by_adapter(adapter));
		goto out;
	}

	/* setup nameserver request */
        ct_iu_req = zfcp_sg_to_address(gid_pn->ct.req);
        ct_iu_req->header.revision = ZFCP_CT_REVISION;
        ct_iu_req->header.gs_type = ZFCP_CT_DIRECTORY_SERVICE;
        ct_iu_req->header.gs_subtype = ZFCP_CT_NAME_SERVER;
        ct_iu_req->header.options = ZFCP_CT_SYNCHRONOUS;
        ct_iu_req->header.cmd_rsp_code = ZFCP_CT_GID_PN;
        ct_iu_req->header.max_res_size = ZFCP_CT_MAX_SIZE;
	ct_iu_req->wwpn = erp_action->port->wwpn;

        /* setup parameters for send generic command */
        gid_pn->ct.port = adapter->nameserver_port;
	gid_pn->ct.handler = zfcp_ns_gid_pn_handler;
	gid_pn->ct.handler_data = (unsigned long) gid_pn;
        gid_pn->ct.timeout = ZFCP_NS_GID_PN_TIMEOUT;
        gid_pn->ct.timer = &erp_action->timer;
	gid_pn->port = erp_action->port;

	ret = zfcp_fsf_send_ct(&gid_pn->ct, adapter->pool.fsf_req_erp,
			       erp_action);
	if (ret) {
		ZFCP_LOG_INFO("error: initiation of gid_pn nameserver request "
                              "failed for adapter %s\n",
			      zfcp_get_busid_by_adapter(adapter));

                zfcp_gid_pn_buffers_free(gid_pn);
	}

 out:
	return ret;
}

/**
 * zfcp_ns_gid_pn_handler - handler for GID_PN nameserver request
 * @data: unsigned long, contains pointer to struct zfcp_gid_pn_data
 */
static void zfcp_ns_gid_pn_handler(unsigned long data)
{
	struct zfcp_port *port;
        struct zfcp_send_ct *ct;
	struct ct_iu_gid_pn_req *ct_iu_req;
	struct ct_iu_gid_pn_resp *ct_iu_resp;
        struct zfcp_gid_pn_data *gid_pn;


	gid_pn = (struct zfcp_gid_pn_data *) data;
	port = gid_pn->port;
        ct = &gid_pn->ct;
	ct_iu_req = zfcp_sg_to_address(ct->req);
	ct_iu_resp = zfcp_sg_to_address(ct->resp);

	if (ct->status != 0)
		goto failed;

	if (zfcp_check_ct_response(&ct_iu_resp->header)) {
		/* FIXME: do we need some specific erp entry points */
		atomic_set_mask(ZFCP_STATUS_PORT_INVALID_WWPN, &port->status);
		goto failed;
	}
	/* paranoia */
	if (ct_iu_req->wwpn != port->wwpn) {
		ZFCP_LOG_NORMAL("bug: wwpn 0x%016Lx returned by nameserver "
				"lookup does not match expected wwpn 0x%016Lx "
				"for adapter %s\n", ct_iu_req->wwpn, port->wwpn,
				zfcp_get_busid_by_port(port));
		goto mismatch;
	}

	/* looks like a valid d_id */
        port->d_id = ct_iu_resp->d_id & ZFCP_DID_MASK;
	atomic_set_mask(ZFCP_STATUS_PORT_DID_DID, &port->status);
	ZFCP_LOG_DEBUG("adapter %s:  wwpn=0x%016Lx ---> d_id=0x%08x\n",
		       zfcp_get_busid_by_port(port), port->wwpn, port->d_id);
	goto out;

 mismatch:
	ZFCP_LOG_DEBUG("CT IUs do not match:\n");
	ZFCP_HEX_DUMP(ZFCP_LOG_LEVEL_DEBUG, (char *) ct_iu_req,
		      sizeof(struct ct_iu_gid_pn_req));
	ZFCP_HEX_DUMP(ZFCP_LOG_LEVEL_DEBUG, (char *) ct_iu_resp,
		      sizeof(struct ct_iu_gid_pn_resp));

 failed:
	ZFCP_LOG_NORMAL("warning: failed gid_pn nameserver request for wwpn "
			"0x%016Lx for adapter %s\n",
			port->wwpn, zfcp_get_busid_by_port(port));
 out:
        zfcp_gid_pn_buffers_free(gid_pn);
	return;
}

/* reject CT_IU reason codes acc. to FC-GS-4 */
static const struct zfcp_rc_entry zfcp_ct_rc[] = {
	{0x01, "invalid command code"},
	{0x02, "invalid version level"},
	{0x03, "logical error"},
	{0x04, "invalid CT_IU size"},
	{0x05, "logical busy"},
	{0x07, "protocol error"},
	{0x09, "unable to perform command request"},
	{0x0b, "command not supported"},
	{0x0d, "server not available"},
	{0x0e, "session could not be established"},
	{0xff, "vendor specific error"},
	{0, NULL},
};

/* LS_RJT reason codes acc. to FC-FS */
static const struct zfcp_rc_entry zfcp_ls_rjt_rc[] = {
	{0x01, "invalid LS_Command code"},
	{0x03, "logical error"},
	{0x05, "logical busy"},
	{0x07, "protocol error"},
	{0x09, "unable to perform command request"},
	{0x0b, "command not supported"},
	{0x0e, "command already in progress"},
	{0xff, "vendor specific error"},
	{0, NULL},
};

/* reject reason codes according to FC-PH/FC-FS */
static const struct zfcp_rc_entry zfcp_p_rjt_rc[] = {
	{0x01, "invalid D_ID"},
	{0x02, "invalid S_ID"},
	{0x03, "Nx_Port not available, temporary"},
	{0x04, "Nx_Port not available, permament"},
	{0x05, "class not supported"},
	{0x06, "delimiter usage error"},
	{0x07, "TYPE not supported"},
	{0x08, "invalid Link_Control"},
	{0x09, "invalid R_CTL field"},
	{0x0a, "invalid F_CTL field"},
	{0x0b, "invalid OX_ID"},
	{0x0c, "invalid RX_ID"},
	{0x0d, "invalid SEQ_ID"},
	{0x0e, "invalid DF_CTL"},
	{0x0f, "invalid SEQ_CNT"},
	{0x10, "invalid parameter field"},
	{0x11, "exchange error"},
	{0x12, "protocol error"},
	{0x13, "incorrect length"},
	{0x14, "unsupported ACK"},
	{0x15, "class of service not supported by entity at FFFFFE"},
	{0x16, "login required"},
	{0x17, "excessive sequences attempted"},
	{0x18, "unable to establish exchange"},
	{0x1a, "fabric path not available"},
	{0x1b, "invalid VC_ID (class 4)"},
	{0x1c, "invalid CS_CTL field"},
	{0x1d, "insufficient resources for VC (class 4)"},
	{0x1f, "invalid class of service"},
	{0x20, "preemption request rejected"},
	{0x21, "preemption not enabled"},
	{0x22, "multicast error"},
	{0x23, "multicast error terminate"},
	{0x24, "process login required"},
	{0xff, "vendor specific reject"},
	{0, NULL},
};

/**
 * zfcp_rc_description - return description for given reaon code
 * @code: reason code
 * @rc_table: table of reason codes and descriptions
 */
static inline const char *
zfcp_rc_description(u8 code, const struct zfcp_rc_entry *rc_table)
{
	const char *descr = "unknown reason code";

	do {
		if (code == rc_table->code) {
			descr = rc_table->description;
			break;
		}
		rc_table++;
	} while (rc_table->code && rc_table->description);

	return descr;
}

/**
 * zfcp_check_ct_response - evaluate reason code for CT_IU
 * @rjt: response payload to an CT_IU request
 * Return: 0 for accept CT_IU, 1 for reject CT_IU or invlid response code
 */
int
zfcp_check_ct_response(struct ct_hdr *rjt)
{
	if (rjt->cmd_rsp_code == ZFCP_CT_ACCEPT)
		return 0;

	if (rjt->cmd_rsp_code != ZFCP_CT_REJECT) {
		ZFCP_LOG_NORMAL("error: invalid Generic Service command/"
				"response code (0x%04hx)\n",
				rjt->cmd_rsp_code);
		return 1;
	}

	ZFCP_LOG_INFO("Generic Service command rejected\n");
	ZFCP_LOG_INFO("%s (0x%02x, 0x%02x, 0x%02x)\n",
		      zfcp_rc_description(rjt->reason_code, zfcp_ct_rc),
		      (u32) rjt->reason_code, (u32) rjt->reason_code_expl,
		      (u32) rjt->vendor_unique);

	return 1;
}

/**
 * zfcp_print_els_rjt - print reject parameter and description for ELS reject
 * @rjt_par: reject parameter acc. to FC-PH/FC-FS
 * @rc_table: table of reason codes and descriptions
 */
static inline void
zfcp_print_els_rjt(struct zfcp_ls_rjt_par *rjt_par,
		   const struct zfcp_rc_entry *rc_table)
{
	ZFCP_LOG_INFO("%s (%02x %02x %02x %02x)\n",
		      zfcp_rc_description(rjt_par->reason_code, rc_table),
		      (u32) rjt_par->action, (u32) rjt_par->reason_code,
		      (u32) rjt_par->reason_expl, (u32) rjt_par->vendor_unique);
}

/**
 * zfcp_fsf_handle_els_rjt - evaluate status qualifier/reason code on ELS reject
 * @sq: status qualifier word
 * @rjt_par: reject parameter as described in FC-PH and FC-FS
 * Return: -EROMTEIO for LS_RJT, -EREMCHG for invalid D_ID, -EIO else
 */
int
zfcp_handle_els_rjt(u32 sq, struct zfcp_ls_rjt_par *rjt_par)
{
	int ret = -EIO;

	if (sq == FSF_IOSTAT_NPORT_RJT) {
		ZFCP_LOG_INFO("ELS rejected (P_RJT)\n");
		zfcp_print_els_rjt(rjt_par, zfcp_p_rjt_rc);
		/* invalid d_id */
		if (rjt_par->reason_code == 0x01)
			ret = -EREMCHG;
	} else if (sq == FSF_IOSTAT_FABRIC_RJT) {
		ZFCP_LOG_INFO("ELS rejected (F_RJT)\n");
		zfcp_print_els_rjt(rjt_par, zfcp_p_rjt_rc);
		/* invalid d_id */
		if (rjt_par->reason_code == 0x01)
			ret = -EREMCHG;
	} else if (sq == FSF_IOSTAT_LS_RJT) {
		ZFCP_LOG_INFO("ELS rejected (LS_RJT)\n");
		zfcp_print_els_rjt(rjt_par, zfcp_ls_rjt_rc);
		ret = -EREMOTEIO;
	} else
		ZFCP_LOG_INFO("unexpected SQ: 0x%02x\n", sq);

	return ret;
}

#undef ZFCP_LOG_AREA