text: /*
   * File...........: linux/drivers/s390/block/dasd_eckd.c
   * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
   *		    Horst Hummel <Horst.Hummel@de.ibm.com>
   *		    Carsten Otte <Cotte@de.ibm.com>
   *		    Martin Schwidefsky <schwidefsky@de.ibm.com>
   * Bugreports.to..: <Linux390@de.ibm.com>
   * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000
   *
   */
  
  #include <linux/stddef.h>
  #include <linux/kernel.h>
  #include <linux/slab.h>
  #include <linux/hdreg.h>	/* HDIO_GETGEO			    */
  #include <linux/bio.h>
  #include <linux/module.h>
  #include <linux/init.h>
  
  #include <asm/debug.h>
  #include <asm/idals.h>
  #include <asm/ebcdic.h>
  #include <asm/io.h>
  #include <asm/todclk.h>
  #include <asm/uaccess.h>
  #include <asm/cio.h>
  #include <asm/ccwdev.h>
  
  #include "dasd_int.h"
  #include "dasd_eckd.h"
  
  #ifdef PRINTK_HEADER
  #undef PRINTK_HEADER
  #endif				/* PRINTK_HEADER */
  #define PRINTK_HEADER "dasd(eckd):"
  
  #define ECKD_C0(i) (i->home_bytes)
  #define ECKD_F(i) (i->formula)
  #define ECKD_F1(i) (ECKD_F(i)==0x01?(i->factors.f_0x01.f1):\
  		    (i->factors.f_0x02.f1))
  #define ECKD_F2(i) (ECKD_F(i)==0x01?(i->factors.f_0x01.f2):\
  		    (i->factors.f_0x02.f2))
  #define ECKD_F3(i) (ECKD_F(i)==0x01?(i->factors.f_0x01.f3):\
  		    (i->factors.f_0x02.f3))
  #define ECKD_F4(i) (ECKD_F(i)==0x02?(i->factors.f_0x02.f4):0)
  #define ECKD_F5(i) (ECKD_F(i)==0x02?(i->factors.f_0x02.f5):0)
  #define ECKD_F6(i) (i->factor6)
  #define ECKD_F7(i) (i->factor7)
  #define ECKD_F8(i) (i->factor8)
  
  MODULE_LICENSE("GPL");
  
  static struct dasd_discipline dasd_eckd_discipline;
  
  struct dasd_eckd_private {
  	struct dasd_eckd_characteristics rdc_data;
  	struct dasd_eckd_confdata conf_data;
  	struct dasd_eckd_path path_data;
  	struct eckd_count count_area[5];
  	int init_cqr_status;
  	int uses_cdl;
  	struct attrib_data_t attrib;	/* e.g. cache operations */
  };
  
  /* The ccw bus type uses this table to find devices that it sends to
   * dasd_eckd_probe */
  static struct ccw_device_id dasd_eckd_ids[] = {
  	{ CCW_DEVICE_DEVTYPE (0x3990, 0, 0x3390, 0), .driver_info = 0x1},
  	{ CCW_DEVICE_DEVTYPE (0x2105, 0, 0x3390, 0), .driver_info = 0x2},
  	{ CCW_DEVICE_DEVTYPE (0x3880, 0, 0x3390, 0), .driver_info = 0x3},
  	{ CCW_DEVICE_DEVTYPE (0x3990, 0, 0x3380, 0), .driver_info = 0x4},
  	{ CCW_DEVICE_DEVTYPE (0x2105, 0, 0x3380, 0), .driver_info = 0x5},
  	{ CCW_DEVICE_DEVTYPE (0x9343, 0, 0x9345, 0), .driver_info = 0x6},
  	{ CCW_DEVICE_DEVTYPE (0x2107, 0, 0x3390, 0), .driver_info = 0x7},
  	{ CCW_DEVICE_DEVTYPE (0x2107, 0, 0x3380, 0), .driver_info = 0x8},
  	{ CCW_DEVICE_DEVTYPE (0x1750, 0, 0x3390, 0), .driver_info = 0x9},
  	{ CCW_DEVICE_DEVTYPE (0x1750, 0, 0x3380, 0), .driver_info = 0xa},
  	{ /* end of list */ },
  };
  
  MODULE_DEVICE_TABLE(ccw, dasd_eckd_ids);
  
  static struct ccw_driver dasd_eckd_driver; /* see below */
  
  /* initial attempt at a probe function. this can be simplified once
   * the other detection code is gone */
  static int
  dasd_eckd_probe (struct ccw_device *cdev)
  {
  	int ret;
  
  	/* set ECKD specific ccw-device options */
  	ret = ccw_device_set_options(cdev, CCWDEV_ALLOW_FORCE);
  	if (ret) {
  		printk(KERN_WARNING
  		       "dasd_eckd_probe: could not set ccw-device options "
  		       "for %s\n", cdev->dev.bus_id);
  		return ret;
  	}
  	ret = dasd_generic_probe(cdev, &dasd_eckd_discipline);
  	return ret;
  }
  
  static int
  dasd_eckd_set_online(struct ccw_device *cdev)
  {
  	return dasd_generic_set_online(cdev, &dasd_eckd_discipline);
  }
  
  static struct ccw_driver dasd_eckd_driver = {
  	.name        = "dasd-eckd",
  	.owner       = THIS_MODULE,
  	.ids         = dasd_eckd_ids,
  	.probe       = dasd_eckd_probe,
  	.remove      = dasd_generic_remove,
  	.set_offline = dasd_generic_set_offline,
  	.set_online  = dasd_eckd_set_online,
  	.notify      = dasd_generic_notify,
  };
  
  static const int sizes_trk0[] = { 28, 148, 84 };
  #define LABEL_SIZE 140
  
  static inline unsigned int
  round_up_multiple(unsigned int no, unsigned int mult)
  {
  	int rem = no % mult;
  	return (rem ? no - rem + mult : no);
  }
  
  static inline unsigned int
  ceil_quot(unsigned int d1, unsigned int d2)
  {
  	return (d1 + (d2 - 1)) / d2;
  }
  
  static unsigned int
  recs_per_track(struct dasd_eckd_characteristics * rdc,
  	       unsigned int kl, unsigned int dl)
  {
  	int dn, kn;
  
  	switch (rdc->dev_type) {
  	case 0x3380:
  		if (kl)
  			return 1499 / (15 + 7 + ceil_quot(kl + 12, 32) +
  				       ceil_quot(dl + 12, 32));
  		else
  			return 1499 / (15 + ceil_quot(dl + 12, 32));
  	case 0x3390:
  		dn = ceil_quot(dl + 6, 232) + 1;
  		if (kl) {
  			kn = ceil_quot(kl + 6, 232) + 1;
  			return 1729 / (10 + 9 + ceil_quot(kl + 6 * kn, 34) +
  				       9 + ceil_quot(dl + 6 * dn, 34));
  		} else
  			return 1729 / (10 + 9 + ceil_quot(dl + 6 * dn, 34));
  	case 0x9345:
  		dn = ceil_quot(dl + 6, 232) + 1;
  		if (kl) {
  			kn = ceil_quot(kl + 6, 232) + 1;
  			return 1420 / (18 + 7 + ceil_quot(kl + 6 * kn, 34) +
  				       ceil_quot(dl + 6 * dn, 34));
  		} else
  			return 1420 / (18 + 7 + ceil_quot(dl + 6 * dn, 34));
  	}
  	return 0;
  }
  
  static int
  check_XRC (struct ccw1         *de_ccw,
             struct DE_eckd_data *data,
             struct dasd_device  *device)
  {
          struct dasd_eckd_private *private;
  	int rc;
  
          private = (struct dasd_eckd_private *) device->private;
  	if (!private->rdc_data.facilities.XRC_supported)
  		return 0;
  
          /* switch on System Time Stamp - needed for XRC Support */
  	data->ga_extended |= 0x08; /* switch on 'Time Stamp Valid'   */
  	data->ga_extended |= 0x02; /* switch on 'Extended Parameter' */
  
  	rc = get_sync_clock(&data->ep_sys_time);
  	/* Ignore return code if sync clock is switched off. */
  	if (rc == -ENOSYS || rc == -EACCES)
  		rc = 0;
  
  	de_ccw->count = sizeof (struct DE_eckd_data);
  	de_ccw->flags |= CCW_FLAG_SLI;
  	return rc;
  }
  
  static int
  define_extent(struct ccw1 * ccw, struct DE_eckd_data * data, int trk,
  	      int totrk, int cmd, struct dasd_device * device)
  {
  	struct dasd_eckd_private *private;
  	struct ch_t geo, beg, end;
  	int rc = 0;
  
  	private = (struct dasd_eckd_private *) device->private;
  
  	ccw->cmd_code = DASD_ECKD_CCW_DEFINE_EXTENT;
  	ccw->flags = 0;
  	ccw->count = 16;
  	ccw->cda = (__u32) __pa(data);
  
  	memset(data, 0, sizeof (struct DE_eckd_data));
  	switch (cmd) {
  	case DASD_ECKD_CCW_READ_HOME_ADDRESS:
  	case DASD_ECKD_CCW_READ_RECORD_ZERO:
  	case DASD_ECKD_CCW_READ:
  	case DASD_ECKD_CCW_READ_MT:
  	case DASD_ECKD_CCW_READ_CKD:
  	case DASD_ECKD_CCW_READ_CKD_MT:
  	case DASD_ECKD_CCW_READ_KD:
  	case DASD_ECKD_CCW_READ_KD_MT:
  	case DASD_ECKD_CCW_READ_COUNT:
  		data->mask.perm = 0x1;
  		data->attributes.operation = private->attrib.operation;
  		break;
  	case DASD_ECKD_CCW_WRITE:
  	case DASD_ECKD_CCW_WRITE_MT:
  	case DASD_ECKD_CCW_WRITE_KD:
  	case DASD_ECKD_CCW_WRITE_KD_MT:
  		data->mask.perm = 0x02;
  		data->attributes.operation = private->attrib.operation;
  		rc = check_XRC (ccw, data, device);
  		break;
  	case DASD_ECKD_CCW_WRITE_CKD:
  	case DASD_ECKD_CCW_WRITE_CKD_MT:
  		data->attributes.operation = DASD_BYPASS_CACHE;
  		rc = check_XRC (ccw, data, device);
  		break;
  	case DASD_ECKD_CCW_ERASE:
  	case DASD_ECKD_CCW_WRITE_HOME_ADDRESS:
  	case DASD_ECKD_CCW_WRITE_RECORD_ZERO:
  		data->mask.perm = 0x3;
  		data->mask.auth = 0x1;
  		data->attributes.operation = DASD_BYPASS_CACHE;
  		rc = check_XRC (ccw, data, device);
  		break;
  	default:
  		DEV_MESSAGE(KERN_ERR, device, "unknown opcode 0x%x", cmd);
  		break;
  	}
  
  	data->attributes.mode = 0x3;	/* ECKD */
  
  	if ((private->rdc_data.cu_type == 0x2105 ||
  	     private->rdc_data.cu_type == 0x2107 ||
  	     private->rdc_data.cu_type == 0x1750)
  	    && !(private->uses_cdl && trk < 2))
  		data->ga_extended |= 0x40; /* Regular Data Format Mode */
  
  	geo.cyl = private->rdc_data.no_cyl;
  	geo.head = private->rdc_data.trk_per_cyl;
  	beg.cyl = trk / geo.head;
  	beg.head = trk % geo.head;
  	end.cyl = totrk / geo.head;
  	end.head = totrk % geo.head;
  
  	/* check for sequential prestage - enhance cylinder range */
  	if (data->attributes.operation == DASD_SEQ_PRESTAGE ||
  	    data->attributes.operation == DASD_SEQ_ACCESS) {
  
  		if (end.cyl + private->attrib.nr_cyl < geo.cyl)
  			end.cyl += private->attrib.nr_cyl;
  		else
  			end.cyl = (geo.cyl - 1);
  	}
  
  	data->beg_ext.cyl = beg.cyl;
  	data->beg_ext.head = beg.head;
  	data->end_ext.cyl = end.cyl;
  	data->end_ext.head = end.head;
  	return rc;
  }
  
  static void
  locate_record(struct ccw1 *ccw, struct LO_eckd_data *data, int trk,
  	      int rec_on_trk, int no_rec, int cmd,
  	      struct dasd_device * device, int reclen)
  {
  	struct dasd_eckd_private *private;
  	int sector;
  	int dn, d;
  
  	private = (struct dasd_eckd_private *) device->private;
  
  	DBF_DEV_EVENT(DBF_INFO, device,
  		  "Locate: trk %d, rec %d, no_rec %d, cmd %d, reclen %d",
  		  trk, rec_on_trk, no_rec, cmd, reclen);
  
  	ccw->cmd_code = DASD_ECKD_CCW_LOCATE_RECORD;
  	ccw->flags = 0;
  	ccw->count = 16;
  	ccw->cda = (__u32) __pa(data);
  
  	memset(data, 0, sizeof (struct LO_eckd_data));
  	sector = 0;
  	if (rec_on_trk) {
  		switch (private->rdc_data.dev_type) {
  		case 0x3390:
  			dn = ceil_quot(reclen + 6, 232);
  			d = 9 + ceil_quot(reclen + 6 * (dn + 1), 34);
  			sector = (49 + (rec_on_trk - 1) * (10 + d)) / 8;
  			break;
  		case 0x3380:
  			d = 7 + ceil_quot(reclen + 12, 32);
  			sector = (39 + (rec_on_trk - 1) * (8 + d)) / 7;
  			break;
  		}
  	}
  	data->sector = sector;
  	data->count = no_rec;
  	switch (cmd) {
  	case DASD_ECKD_CCW_WRITE_HOME_ADDRESS:
  		data->operation.orientation = 0x3;
  		data->operation.operation = 0x03;
  		break;
  	case DASD_ECKD_CCW_READ_HOME_ADDRESS:
  		data->operation.orientation = 0x3;
  		data->operation.operation = 0x16;
  		break;
  	case DASD_ECKD_CCW_WRITE_RECORD_ZERO:
  		data->operation.orientation = 0x1;
  		data->operation.operation = 0x03;
  		data->count++;
  		break;
  	case DASD_ECKD_CCW_READ_RECORD_ZERO:
  		data->operation.orientation = 0x3;
  		data->operation.operation = 0x16;
  		data->count++;
  		break;
  	case DASD_ECKD_CCW_WRITE:
  	case DASD_ECKD_CCW_WRITE_MT:
  	case DASD_ECKD_CCW_WRITE_KD:
  	case DASD_ECKD_CCW_WRITE_KD_MT:
  		data->auxiliary.last_bytes_used = 0x1;
  		data->length = reclen;
  		data->operation.operation = 0x01;
  		break;
  	case DASD_ECKD_CCW_WRITE_CKD:
  	case DASD_ECKD_CCW_WRITE_CKD_MT:
  		data->auxiliary.last_bytes_used = 0x1;
  		data->length = reclen;
  		data->operation.operation = 0x03;
  		break;
  	case DASD_ECKD_CCW_READ:
  	case DASD_ECKD_CCW_READ_MT:
  	case DASD_ECKD_CCW_READ_KD:
  	case DASD_ECKD_CCW_READ_KD_MT:
  		data->auxiliary.last_bytes_used = 0x1;
  		data->length = reclen;
  		data->operation.operation = 0x06;
  		break;
  	case DASD_ECKD_CCW_READ_CKD:
  	case DASD_ECKD_CCW_READ_CKD_MT:
  		data->auxiliary.last_bytes_used = 0x1;
  		data->length = reclen;
  		data->operation.operation = 0x16;
  		break;
  	case DASD_ECKD_CCW_READ_COUNT:
  		data->operation.operation = 0x06;
  		break;
  	case DASD_ECKD_CCW_ERASE:
  		data->length = reclen;
  		data->auxiliary.last_bytes_used = 0x1;
  		data->operation.operation = 0x0b;
  		break;
  	default:
  		DEV_MESSAGE(KERN_ERR, device, "unknown opcode 0x%x", cmd);
  	}
  	data->seek_addr.cyl = data->search_arg.cyl =
  		trk / private->rdc_data.trk_per_cyl;
  	data->seek_addr.head = data->search_arg.head =
  		trk % private->rdc_data.trk_per_cyl;
  	data->search_arg.record = rec_on_trk;
  }
  
  /*
   * Returns 1 if the block is one of the special blocks that needs
   * to get read/written with the KD variant of the command.
   * That is DASD_ECKD_READ_KD_MT instead of DASD_ECKD_READ_MT and
   * DASD_ECKD_WRITE_KD_MT instead of DASD_ECKD_WRITE_MT.
   * Luckily the KD variants differ only by one bit (0x08) from the
   * normal variant. So don't wonder about code like:
   * if (dasd_eckd_cdl_special(blk_per_trk, recid))
   *         ccw->cmd_code |= 0x8;
   */
  static inline int
  dasd_eckd_cdl_special(int blk_per_trk, int recid)
  {
  	if (recid < 3)
  		return 1;
  	if (recid < blk_per_trk)
  		return 0;
  	if (recid < 2 * blk_per_trk)
  		return 1;
  	return 0;
  }
  
  /*
   * Returns the record size for the special blocks of the cdl format.
   * Only returns something useful if dasd_eckd_cdl_special is true
   * for the recid.
   */
  static inline int
  dasd_eckd_cdl_reclen(int recid)
  {
  	if (recid < 3)
  		return sizes_trk0[recid];
  	return LABEL_SIZE;
  }
  
  /*
   * Generate device unique id that specifies the physical device.
   */
  static int
  dasd_eckd_generate_uid(struct dasd_device *device, struct dasd_uid *uid)
  {
  	struct dasd_eckd_private *private;
  	struct dasd_eckd_confdata *confdata;
  
  	private = (struct dasd_eckd_private *) device->private;
  	if (!private)
  		return -ENODEV;
  	confdata = &private->conf_data;
  	if (!confdata)
  		return -ENODEV;
  
  	memset(uid, 0, sizeof(struct dasd_uid));
  	memcpy(uid->vendor, confdata->ned1.HDA_manufacturer,
  	       sizeof(uid->vendor) - 1);
  	EBCASC(uid->vendor, sizeof(uid->vendor) - 1);
  	memcpy(uid->serial, confdata->ned1.HDA_location,
  	       sizeof(uid->serial) - 1);
  	EBCASC(uid->serial, sizeof(uid->serial) - 1);
  	uid->ssid = confdata->neq.subsystemID;
  	if (confdata->ned2.sneq.flags == 0x40) {
  		uid->alias = 1;
  		uid->unit_addr = confdata->ned2.sneq.base_unit_addr;
  	} else
  		uid->unit_addr = confdata->ned1.unit_addr;
  
  	return 0;
  }
  
  static struct dasd_ccw_req *dasd_eckd_build_rcd_lpm(struct dasd_device *device,
  						    void *rcd_buffer,
  						    struct ciw *ciw, __u8 lpm)
  {
  	struct dasd_ccw_req *cqr;
  	struct ccw1 *ccw;
  
  	cqr = dasd_smalloc_request("ECKD", 1 /* RCD */, ciw->count, device);
  
  	if (IS_ERR(cqr)) {
  		DEV_MESSAGE(KERN_WARNING, device, "%s",
  			    "Could not allocate RCD request");
  		return cqr;
  	}
  
  	ccw = cqr->cpaddr;
  	ccw->cmd_code = ciw->cmd;
  	ccw->cda = (__u32)(addr_t)rcd_buffer;
  	ccw->count = ciw->count;
  
  	cqr->device = device;
  	cqr->expires = 10*HZ;
  	cqr->lpm = lpm;
  	clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
  	cqr->retries = 2;
  	cqr->buildclk = get_clock();
  	cqr->status = DASD_CQR_FILLED;
  	return cqr;
  }
  
  static int dasd_eckd_read_conf_lpm(struct dasd_device *device,
  				   void **rcd_buffer,
  				   int *rcd_buffer_size, __u8 lpm)
  {
  	struct ciw *ciw;
  	char *rcd_buf = NULL;
  	int ret;
  	struct dasd_ccw_req *cqr;
  
  	/*
  	 * scan for RCD command in extended SenseID data
  	 */
  	ciw = ccw_device_get_ciw(device->cdev, CIW_TYPE_RCD);
  	if (!ciw || ciw->cmd == 0) {
  		ret = -EOPNOTSUPP;
  		goto out_error;
  	}
  	rcd_buf = kzalloc(ciw->count, GFP_KERNEL | GFP_DMA);
  	if (!rcd_buf) {
  		ret = -ENOMEM;
  		goto out_error;
  	}
  	cqr = dasd_eckd_build_rcd_lpm(device, rcd_buf, ciw, lpm);
  	if (IS_ERR(cqr)) {
  		ret =  PTR_ERR(cqr);
  		goto out_error;
  	}
  	ret = dasd_sleep_on(cqr);
  	/*
  	 * on success we update the user input parms
  	 */
  	dasd_sfree_request(cqr, cqr->device);
  	if (ret)
  		goto out_error;
  
  	*rcd_buffer_size = ciw->count;
  	*rcd_buffer = rcd_buf;
  	return 0;
  out_error:
  	kfree(rcd_buf);
  	*rcd_buffer = NULL;
  	*rcd_buffer_size = 0;
  	return ret;
  }
  
  static int
  dasd_eckd_read_conf(struct dasd_device *device)
  {
  	void *conf_data;
  	int conf_len, conf_data_saved;
  	int rc;
  	__u8 lpm;
  	struct dasd_eckd_private *private;
  	struct dasd_eckd_path *path_data;
  
  	private = (struct dasd_eckd_private *) device->private;
  	path_data = (struct dasd_eckd_path *) &private->path_data;
  	path_data->opm = ccw_device_get_path_mask(device->cdev);
  	lpm = 0x80;
  	conf_data_saved = 0;
  
  	/* get configuration data per operational path */
  	for (lpm = 0x80; lpm; lpm>>= 1) {
  		if (lpm & path_data->opm){
  			rc = dasd_eckd_read_conf_lpm(device, &conf_data,
  						     &conf_len, lpm);
  			if (rc && rc != -EOPNOTSUPP) {	/* -EOPNOTSUPP is ok */
  				MESSAGE(KERN_WARNING,
  					"Read configuration data returned "
  					"error %d", rc);
  				return rc;
  			}
  			if (conf_data == NULL) {
  				MESSAGE(KERN_WARNING, "%s", "No configuration "
  					"data retrieved");
  				continue;	/* no error */
  			}
  			if (conf_len != sizeof (struct dasd_eckd_confdata)) {
  				MESSAGE(KERN_WARNING,
  					"sizes of configuration data mismatch"
  					"%d (read) vs %ld (expected)",
  					conf_len,
  					sizeof (struct dasd_eckd_confdata));
  				kfree(conf_data);
  				continue;	/* no error */
  			}
  			/* save first valid configuration data */
  			if (!conf_data_saved){
  				memcpy(&private->conf_data, conf_data,
  				       sizeof (struct dasd_eckd_confdata));
  				conf_data_saved++;
  			}
  			switch (((char *)conf_data)[242] & 0x07){
  			case 0x02:
  				path_data->npm |= lpm;
  				break;
  			case 0x03:
  				path_data->ppm |= lpm;
  				break;
  			}
  			kfree(conf_data);
  		}
  	}
  	return 0;
  }
  
  /*
   * Build CP for Perform Subsystem Function - SSC.
   */
  static struct dasd_ccw_req *
  dasd_eckd_build_psf_ssc(struct dasd_device *device)
  {
         struct dasd_ccw_req *cqr;
         struct dasd_psf_ssc_data *psf_ssc_data;
         struct ccw1 *ccw;
  
         cqr = dasd_smalloc_request("ECKD", 1 /* PSF */ ,
  				  sizeof(struct dasd_psf_ssc_data),
  				  device);
  
         if (IS_ERR(cqr)) {
  	       DEV_MESSAGE(KERN_WARNING, device, "%s",
  			   "Could not allocate PSF-SSC request");
  	       return cqr;
         }
         psf_ssc_data = (struct dasd_psf_ssc_data *)cqr->data;
         psf_ssc_data->order = PSF_ORDER_SSC;
         psf_ssc_data->suborder = 0x08;
  
         ccw = cqr->cpaddr;
         ccw->cmd_code = DASD_ECKD_CCW_PSF;
         ccw->cda = (__u32)(addr_t)psf_ssc_data;
         ccw->count = 66;
  
         cqr->device = device;
         cqr->expires = 10*HZ;
         cqr->buildclk = get_clock();
         cqr->status = DASD_CQR_FILLED;
         return cqr;
  }
  
  /*
   * Perform Subsystem Function.
   * It is necessary to trigger CIO for channel revalidation since this
   * call might change behaviour of DASD devices.
   */
  static int
  dasd_eckd_psf_ssc(struct dasd_device *device)
  {
         struct dasd_ccw_req *cqr;
         int rc;
  
         cqr = dasd_eckd_build_psf_ssc(device);
         if (IS_ERR(cqr))
  	       return PTR_ERR(cqr);
  
         rc = dasd_sleep_on(cqr);
         if (!rc)
  	       /* trigger CIO to reprobe devices */
  	       css_schedule_reprobe();
         dasd_sfree_request(cqr, cqr->device);
         return rc;
  }
  
  /*
   * Valide storage server of current device.
   */
  static int
  dasd_eckd_validate_server(struct dasd_device *device, struct dasd_uid *uid)
  {
  	int rc;
  
  	/* Currently PAV is the only reason to 'validate' server on LPAR */
  	if (dasd_nopav || MACHINE_IS_VM)
  		return 0;
  
  	rc = dasd_eckd_psf_ssc(device);
  	/* may be requested feature is not available on server,
  	 * therefore just report error and go ahead */
  	DEV_MESSAGE(KERN_INFO, device,
  		    "PSF-SSC on storage subsystem %s.%s.%04x returned rc=%d",
  		    uid->vendor, uid->serial, uid->ssid, rc);
  	/* RE-Read Configuration Data */
  	return dasd_eckd_read_conf(device);
  }
  
  /*
   * Check device characteristics.
   * If the device is accessible using ECKD discipline, the device is enabled.
   */
  static int
  dasd_eckd_check_characteristics(struct dasd_device *device)
  {
  	struct dasd_eckd_private *private;
  	struct dasd_uid uid;
  	void *rdc_data;
  	int rc;
  
  	private = (struct dasd_eckd_private *) device->private;
  	if (private == NULL) {
  		private = kzalloc(sizeof(struct dasd_eckd_private),
  				  GFP_KERNEL | GFP_DMA);
  		if (private == NULL) {
  			DEV_MESSAGE(KERN_WARNING, device, "%s",
  				    "memory allocation failed for private "
  				    "data");
  			return -ENOMEM;
  		}
  		device->private = (void *) private;
  	}
  	/* Invalidate status of initial analysis. */
  	private->init_cqr_status = -1;
  	/* Set default cache operations. */
  	private->attrib.operation = DASD_NORMAL_CACHE;
  	private->attrib.nr_cyl = 0;
  
  	/* Read Configuration Data */
  	rc = dasd_eckd_read_conf(device);
  	if (rc)
  		return rc;
  
  	/* Generate device unique id and register in devmap */
  	rc = dasd_eckd_generate_uid(device, &uid);
  	if (rc)
  		return rc;
  	rc = dasd_set_uid(device->cdev, &uid);
  	if (rc == 1)	/* new server found */
  		rc = dasd_eckd_validate_server(device, &uid);
  	if (rc)
  		return rc;
  
  	/* Read Device Characteristics */
  	rdc_data = (void *) &(private->rdc_data);
  	memset(rdc_data, 0, sizeof(rdc_data));
  	rc = dasd_generic_read_dev_chars(device, "ECKD", &rdc_data, 64);
  	if (rc)
  		DEV_MESSAGE(KERN_WARNING, device,
  			    "Read device characteristics returned "
  			    "rc=%d", rc);
  
  	DEV_MESSAGE(KERN_INFO, device,
  		    "%04X/%02X(CU:%04X/%02X) Cyl:%d Head:%d Sec:%d",
  		    private->rdc_data.dev_type,
  		    private->rdc_data.dev_model,
  		    private->rdc_data.cu_type,
  		    private->rdc_data.cu_model.model,
  		    private->rdc_data.no_cyl,
  		    private->rdc_data.trk_per_cyl,
  		    private->rdc_data.sec_per_trk);
  	return rc;
  }
  
  static struct dasd_ccw_req *
  dasd_eckd_analysis_ccw(struct dasd_device *device)
  {
  	struct dasd_eckd_private *private;
  	struct eckd_count *count_data;
  	struct LO_eckd_data *LO_data;
  	struct dasd_ccw_req *cqr;
  	struct ccw1 *ccw;
  	int cplength, datasize;
  	int i;
  
  	private = (struct dasd_eckd_private *) device->private;
  
  	cplength = 8;
  	datasize = sizeof(struct DE_eckd_data) + 2*sizeof(struct LO_eckd_data);
  	cqr = dasd_smalloc_request(dasd_eckd_discipline.name,
  				   cplength, datasize, device);
  	if (IS_ERR(cqr))
  		return cqr;
  	ccw = cqr->cpaddr;
  	/* Define extent for the first 3 tracks. */
  	define_extent(ccw++, cqr->data, 0, 2,
  		      DASD_ECKD_CCW_READ_COUNT, device);
  	LO_data = cqr->data + sizeof (struct DE_eckd_data);
  	/* Locate record for the first 4 records on track 0. */
  	ccw[-1].flags |= CCW_FLAG_CC;
  	locate_record(ccw++, LO_data++, 0, 0, 4,
  		      DASD_ECKD_CCW_READ_COUNT, device, 0);
  
  	count_data = private->count_area;
  	for (i = 0; i < 4; i++) {
  		ccw[-1].flags |= CCW_FLAG_CC;
  		ccw->cmd_code = DASD_ECKD_CCW_READ_COUNT;
  		ccw->flags = 0;
  		ccw->count = 8;
  		ccw->cda = (__u32)(addr_t) count_data;
  		ccw++;
  		count_data++;
  	}
  
  	/* Locate record for the first record on track 2. */
  	ccw[-1].flags |= CCW_FLAG_CC;
  	locate_record(ccw++, LO_data++, 2, 0, 1,
  		      DASD_ECKD_CCW_READ_COUNT, device, 0);
  	/* Read count ccw. */
  	ccw[-1].flags |= CCW_FLAG_CC;
  	ccw->cmd_code = DASD_ECKD_CCW_READ_COUNT;
  	ccw->flags = 0;
  	ccw->count = 8;
  	ccw->cda = (__u32)(addr_t) count_data;
  
  	cqr->device = device;
  	cqr->retries = 0;
  	cqr->buildclk = get_clock();
  	cqr->status = DASD_CQR_FILLED;
  	return cqr;
  }
  
  /*
   * This is the callback function for the init_analysis cqr. It saves
   * the status of the initial analysis ccw before it frees it and kicks
   * the device to continue the startup sequence. This will call
   * dasd_eckd_do_analysis again (if the devices has not been marked
   * for deletion in the meantime).
   */
  static void
  dasd_eckd_analysis_callback(struct dasd_ccw_req *init_cqr, void *data)
  {
  	struct dasd_eckd_private *private;
  	struct dasd_device *device;
  
  	device = init_cqr->device;
  	private = (struct dasd_eckd_private *) device->private;
  	private->init_cqr_status = init_cqr->status;
  	dasd_sfree_request(init_cqr, device);
  	dasd_kick_device(device);
  }
  
  static int
  dasd_eckd_start_analysis(struct dasd_device *device)
  {
  	struct dasd_eckd_private *private;
  	struct dasd_ccw_req *init_cqr;
  
  	private = (struct dasd_eckd_private *) device->private;
  	init_cqr = dasd_eckd_analysis_ccw(device);
  	if (IS_ERR(init_cqr))
  		return PTR_ERR(init_cqr);
  	init_cqr->callback = dasd_eckd_analysis_callback;
  	init_cqr->callback_data = NULL;
  	init_cqr->expires = 5*HZ;
  	dasd_add_request_head(init_cqr);
  	return -EAGAIN;
  }
  
  static int
  dasd_eckd_end_analysis(struct dasd_device *device)
  {
  	struct dasd_eckd_private *private;
  	struct eckd_count *count_area;
  	unsigned int sb, blk_per_trk;
  	int status, i;
  
  	private = (struct dasd_eckd_private *) device->private;
  	status = private->init_cqr_status;
  	private->init_cqr_status = -1;
  	if (status != DASD_CQR_DONE) {
  		DEV_MESSAGE(KERN_WARNING, device, "%s",
  			    "volume analysis returned unformatted disk");
  		return -EMEDIUMTYPE;
  	}
  
  	private->uses_cdl = 1;
  	/* Calculate number of blocks/records per track. */
  	blk_per_trk = recs_per_track(&private->rdc_data, 0, device->bp_block);
  	/* Check Track 0 for Compatible Disk Layout */
  	count_area = NULL;
  	for (i = 0; i < 3; i++) {
  		if (private->count_area[i].kl != 4 ||
  		    private->count_area[i].dl != dasd_eckd_cdl_reclen(i) - 4) {
  			private->uses_cdl = 0;
  			break;
  		}
  	}
  	if (i == 3)
  		count_area = &private->count_area[4];
  
  	if (private->uses_cdl == 0) {
  		for (i = 0; i < 5; i++) {
  			if ((private->count_area[i].kl != 0) ||
  			    (private->count_area[i].dl !=
  			     private->count_area[0].dl))
  				break;
  		}
  		if (i == 5)
  			count_area = &private->count_area[0];
  	} else {
  		if (private->count_area[3].record == 1)
  			DEV_MESSAGE(KERN_WARNING, device, "%s",
  				    "Trk 0: no records after VTOC!");
  	}
  	if (count_area != NULL && count_area->kl == 0) {
  		/* we found notthing violating our disk layout */
  		if (dasd_check_blocksize(count_area->dl) == 0)
  			device->bp_block = count_area->dl;
  	}
  	if (device->bp_block == 0) {
  		DEV_MESSAGE(KERN_WARNING, device, "%s",
  			    "Volume has incompatible disk layout");
  		return -EMEDIUMTYPE;
  	}
  	device->s2b_shift = 0;	/* bits to shift 512 to get a block */
  	for (sb = 512; sb < device->bp_block; sb = sb << 1)
  		device->s2b_shift++;
  
  	blk_per_trk = recs_per_track(&private->rdc_data, 0, device->bp_block);
  	device->blocks = (private->rdc_data.no_cyl *
  			  private->rdc_data.trk_per_cyl *
  			  blk_per_trk);
  
  	DEV_MESSAGE(KERN_INFO, device,
  		    "(%dkB blks): %dkB at %dkB/trk %s",
  		    (device->bp_block >> 10),
  		    ((private->rdc_data.no_cyl *
  		      private->rdc_data.trk_per_cyl *
  		      blk_per_trk * (device->bp_block >> 9)) >> 1),
  		    ((blk_per_trk * device->bp_block) >> 10),
  		    private->uses_cdl ?
  		    "compatible disk layout" : "linux disk layout");
  
  	return 0;
  }
  
  static int
  dasd_eckd_do_analysis(struct dasd_device *device)
  {
  	struct dasd_eckd_private *private;
  
  	private = (struct dasd_eckd_private *) device->private;
  	if (private->init_cqr_status < 0)
  		return dasd_eckd_start_analysis(device);
  	else
  		return dasd_eckd_end_analysis(device);
  }
  
  static int
  dasd_eckd_fill_geometry(struct dasd_device *device, struct hd_geometry *geo)
  {
  	struct dasd_eckd_private *private;
  
  	private = (struct dasd_eckd_private *) device->private;
  	if (dasd_check_blocksize(device->bp_block) == 0) {
  		geo->sectors = recs_per_track(&private->rdc_data,
  					      0, device->bp_block);
  	}
  	geo->cylinders = private->rdc_data.no_cyl;
  	geo->heads = private->rdc_data.trk_per_cyl;
  	return 0;
  }
  
  static struct dasd_ccw_req *
  dasd_eckd_format_device(struct dasd_device * device,
  			struct format_data_t * fdata)
  {
  	struct dasd_eckd_private *private;
  	struct dasd_ccw_req *fcp;
  	struct eckd_count *ect;
  	struct ccw1 *ccw;
  	void *data;
  	int rpt, cyl, head;
  	int cplength, datasize;
  	int i;
  
  	private = (struct dasd_eckd_private *) device->private;
  	rpt = recs_per_track(&private->rdc_data, 0, fdata->blksize);
  	cyl = fdata->start_unit / private->rdc_data.trk_per_cyl;
  	head = fdata->start_unit % private->rdc_data.trk_per_cyl;
  
  	/* Sanity checks. */
  	if (fdata->start_unit >=
  	    (private->rdc_data.no_cyl * private->rdc_data.trk_per_cyl)) {
  		DEV_MESSAGE(KERN_INFO, device, "Track no %d too big!",
  			    fdata->start_unit);
  		return ERR_PTR(-EINVAL);
  	}
  	if (fdata->start_unit > fdata->stop_unit) {
  		DEV_MESSAGE(KERN_INFO, device, "Track %d reached! ending.",
  			    fdata->start_unit);
  		return ERR_PTR(-EINVAL);
  	}
  	if (dasd_check_blocksize(fdata->blksize) != 0) {
  		DEV_MESSAGE(KERN_WARNING, device,
  			    "Invalid blocksize %d...terminating!",
  			    fdata->blksize);
  		return ERR_PTR(-EINVAL);
  	}
  
  	/*
  	 * fdata->intensity is a bit string that tells us what to do:
  	 *   Bit 0: write record zero
  	 *   Bit 1: write home address, currently not supported
  	 *   Bit 2: invalidate tracks
  	 *   Bit 3: use OS/390 compatible disk layout (cdl)
  	 * Only some bit combinations do make sense.
  	 */
  	switch (fdata->intensity) {
  	case 0x00:	/* Normal format */
  	case 0x08:	/* Normal format, use cdl. */
  		cplength = 2 + rpt;
  		datasize = sizeof(struct DE_eckd_data) +
  			sizeof(struct LO_eckd_data) +
  			rpt * sizeof(struct eckd_count);
  		break;
  	case 0x01:	/* Write record zero and format track. */
  	case 0x09:	/* Write record zero and format track, use cdl. */
  		cplength = 3 + rpt;
  		datasize = sizeof(struct DE_eckd_data) +
  			sizeof(struct LO_eckd_data) +
  			sizeof(struct eckd_count) +
  			rpt * sizeof(struct eckd_count);
  		break;
  	case 0x04:	/* Invalidate track. */
  	case 0x0c:	/* Invalidate track, use cdl. */
  		cplength = 3;
  		datasize = sizeof(struct DE_eckd_data) +
  			sizeof(struct LO_eckd_data) +
  			sizeof(struct eckd_count);
  		break;
  	default:
  		DEV_MESSAGE(KERN_WARNING, device, "Invalid flags 0x%x.",
  			    fdata->intensity);
  		return ERR_PTR(-EINVAL);
  	}
  	/* Allocate the format ccw request. */
  	fcp = dasd_smalloc_request(dasd_eckd_discipline.name,
  				   cplength, datasize, device);
  	if (IS_ERR(fcp))
  		return fcp;
  
  	data = fcp->data;
  	ccw = fcp->cpaddr;
  
  	switch (fdata->intensity & ~0x08) {
  	case 0x00: /* Normal format. */
  		define_extent(ccw++, (struct DE_eckd_data *) data,
  			      fdata->start_unit, fdata->start_unit,
  			      DASD_ECKD_CCW_WRITE_CKD, device);
  		data += sizeof(struct DE_eckd_data);
  		ccw[-1].flags |= CCW_FLAG_CC;
  		locate_record(ccw++, (struct LO_eckd_data *) data,
  			      fdata->start_unit, 0, rpt,
  			      DASD_ECKD_CCW_WRITE_CKD, device,
  			      fdata->blksize);
  		data += sizeof(struct LO_eckd_data);
  		break;
  	case 0x01: /* Write record zero + format track. */
  		define_extent(ccw++, (struct DE_eckd_data *) data,
  			      fdata->start_unit, fdata->start_unit,
  			      DASD_ECKD_CCW_WRITE_RECORD_ZERO,
  			      device);
  		data += sizeof(struct DE_eckd_data);
  		ccw[-1].flags |= CCW_FLAG_CC;
  		locate_record(ccw++, (struct LO_eckd_data *) data,
  			      fdata->start_unit, 0, rpt + 1,
  			      DASD_ECKD_CCW_WRITE_RECORD_ZERO, device,
  			      device->bp_block);
  		data += sizeof(struct LO_eckd_data);
  		break;
  	case 0x04: /* Invalidate track. */
  		define_extent(ccw++, (struct DE_eckd_data *) data,
  			      fdata->start_unit, fdata->start_unit,
  			      DASD_ECKD_CCW_WRITE_CKD, device);
  		data += sizeof(struct DE_eckd_data);
  		ccw[-1].flags |= CCW_FLAG_CC;
  		locate_record(ccw++, (struct LO_eckd_data *) data,
  			      fdata->start_unit, 0, 1,
  			      DASD_ECKD_CCW_WRITE_CKD, device, 8);
  		data += sizeof(struct LO_eckd_data);
  		break;
  	}
  	if (fdata->intensity & 0x01) {	/* write record zero */
  		ect = (struct eckd_count *) data;
  		data += sizeof(struct eckd_count);
  		ect->cyl = cyl;
  		ect->head = head;
  		ect->record = 0;
  		ect->kl = 0;
  		ect->dl = 8;
  		ccw[-1].flags |= CCW_FLAG_CC;
  		ccw->cmd_code = DASD_ECKD_CCW_WRITE_RECORD_ZERO;
  		ccw->flags = CCW_FLAG_SLI;
  		ccw->count = 8;
  		ccw->cda = (__u32)(addr_t) ect;
  		ccw++;
  	}
  	if ((fdata->intensity & ~0x08) & 0x04) {	/* erase track */
  		ect = (struct eckd_count *) data;
  		data += sizeof(struct eckd_count);
  		ect->cyl = cyl;
  		ect->head = head;
  		ect->record = 1;
  		ect->kl = 0;
  		ect->dl = 0;
  		ccw[-1].flags |= CCW_FLAG_CC;
  		ccw->cmd_code = DASD_ECKD_CCW_WRITE_CKD;
  		ccw->flags = CCW_FLAG_SLI;
  		ccw->count = 8;
  		ccw->cda = (__u32)(addr_t) ect;
  	} else {		/* write remaining records */
  		for (i = 0; i < rpt; i++) {
  			ect = (struct eckd_count *) data;
  			data += sizeof(struct eckd_count);
  			ect->cyl = cyl;
  			ect->head = head;
  			ect->record = i + 1;
  			ect->kl = 0;
  			ect->dl = fdata->blksize;
  			/* Check for special tracks 0-1 when formatting CDL */
  			if ((fdata->intensity & 0x08) &&
  			    fdata->start_unit == 0) {
  				if (i < 3) {
  					ect->kl = 4;
  					ect->dl = sizes_trk0[i] - 4;
  				}
  			}
  			if ((fdata->intensity & 0x08) &&
  			    fdata->start_unit == 1) {
  				ect->kl = 44;
  				ect->dl = LABEL_SIZE - 44;
  			}
  			ccw[-1].flags |= CCW_FLAG_CC;
  			ccw->cmd_code = DASD_ECKD_CCW_WRITE_CKD;
  			ccw->flags = CCW_FLAG_SLI;
  			ccw->count = 8;
  			ccw->cda = (__u32)(addr_t) ect;
  			ccw++;
  		}
  	}
  	fcp->device = device;
  	fcp->retries = 2;	/* set retry counter to enable ERP */
  	fcp->buildclk = get_clock();
  	fcp->status = DASD_CQR_FILLED;
  	return fcp;
  }
  
  static dasd_era_t
  dasd_eckd_examine_error(struct dasd_ccw_req * cqr, struct irb * irb)
  {
  	struct dasd_device *device = (struct dasd_device *) cqr->device;
  	struct ccw_device *cdev = device->cdev;
  
  	if (irb->scsw.cstat == 0x00 &&
  	    irb->scsw.dstat == (DEV_STAT_CHN_END | DEV_STAT_DEV_END))
  		return dasd_era_none;
  
  	switch (cdev->id.cu_type) {
  	case 0x3990:
  	case 0x2105:
  	case 0x2107:
  	case 0x1750:
  		return dasd_3990_erp_examine(cqr, irb);
  	case 0x9343:
  		return dasd_9343_erp_examine(cqr, irb);
  	case 0x3880:
  	default:
  		DEV_MESSAGE(KERN_WARNING, device, "%s",
  			    "default (unknown CU type) - RECOVERABLE return");
  		return dasd_era_recover;
  	}
  }
  
  static dasd_erp_fn_t
  dasd_eckd_erp_action(struct dasd_ccw_req * cqr)
  {
  	struct dasd_device *device = (struct dasd_device *) cqr->device;
  	struct ccw_device *cdev = device->cdev;
  
  	switch (cdev->id.cu_type) {
  	case 0x3990:
  	case 0x2105:
  	case 0x2107:
  	case 0x1750:
  		return dasd_3990_erp_action;
  	case 0x9343:
  	case 0x3880:
  	default:
  		return dasd_default_erp_action;
  	}
  }
  
  static dasd_erp_fn_t
  dasd_eckd_erp_postaction(struct dasd_ccw_req * cqr)
  {
  	return dasd_default_erp_postaction;
  }
  
  static struct dasd_ccw_req *
  dasd_eckd_build_cp(struct dasd_device * device, struct request *req)
  {
  	struct dasd_eckd_private *private;
  	unsigned long *idaws;
  	struct LO_eckd_data *LO_data;
  	struct dasd_ccw_req *cqr;
  	struct ccw1 *ccw;
  	struct req_iterator iter;
  	struct bio_vec *bv;
  	char *dst;
  	unsigned int blksize, blk_per_trk, off;
  	int count, cidaw, cplength, datasize;
  	sector_t recid, first_rec, last_rec;
  	sector_t first_trk, last_trk;
  	unsigned int first_offs, last_offs;
  	unsigned char cmd, rcmd;
  
  	private = (struct dasd_eckd_private *) device->private;
  	if (rq_data_dir(req) == READ)
  		cmd = DASD_ECKD_CCW_READ_MT;
  	else if (rq_data_dir(req) == WRITE)
  		cmd = DASD_ECKD_CCW_WRITE_MT;
  	else
  		return ERR_PTR(-EINVAL);
  	/* Calculate number of blocks/records per track. */
  	blksize = device->bp_block;
  	blk_per_trk = recs_per_track(&private->rdc_data, 0, blksize);
  	/* Calculate record id of first and last block. */
  	first_rec = first_trk = req->sector >> device->s2b_shift;
  	first_offs = sector_div(first_trk, blk_per_trk);
  	last_rec = last_trk =
  		(req->sector + req->nr_sectors - 1) >> device->s2b_shift;
  	last_offs = sector_div(last_trk, blk_per_trk);
  	/* Check struct bio and count the number of blocks for the request. */
  	count = 0;
  	cidaw = 0;
  	rq_for_each_segment(bv, req, iter) {
  		if (bv->bv_len & (blksize - 1))
  			/* Eckd can only do full blocks. */
  			return ERR_PTR(-EINVAL);
  		count += bv->bv_len >> (device->s2b_shift + 9);
  #if defined(CONFIG_64BIT)
  		if (idal_is_needed (page_address(bv->bv_page), bv->bv_len))
  			cidaw += bv->bv_len >> (device->s2b_shift + 9);
  #endif
  	}
  	/* Paranoia. */
  	if (count != last_rec - first_rec + 1)
  		return ERR_PTR(-EINVAL);
  	/* 1x define extent + 1x locate record + number of blocks */
  	cplength = 2 + count;
  	/* 1x define extent + 1x locate record + cidaws*sizeof(long) */
  	datasize = sizeof(struct DE_eckd_data) + sizeof(struct LO_eckd_data) +
  		cidaw * sizeof(unsigned long);
  	/* Find out the number of additional locate record ccws for cdl. */
  	if (private->uses_cdl && first_rec < 2*blk_per_trk) {
  		if (last_rec >= 2*blk_per_trk)
  			count = 2*blk_per_trk - first_rec;
  		cplength += count;
  		datasize += count*sizeof(struct LO_eckd_data);
  	}
  	/* Allocate the ccw request. */
  	cqr = dasd_smalloc_request(dasd_eckd_discipline.name,
  				   cplength, datasize, device);
  	if (IS_ERR(cqr))
  		return cqr;
  	ccw = cqr->cpaddr;
  	/* First ccw is define extent. */
  	if (define_extent(ccw++, cqr->data, first_trk,
  			  last_trk, cmd, device) == -EAGAIN) {
  		/* Clock not in sync and XRC is enabled. Try again later. */
  		dasd_sfree_request(cqr, device);
  		return ERR_PTR(-EAGAIN);
  	}
  	/* Build locate_record+read/write/ccws. */
  	idaws = (unsigned long *) (cqr->data + sizeof(struct DE_eckd_data));
  	LO_data = (struct LO_eckd_data *) (idaws + cidaw);
  	recid = first_rec;
  	if (private->uses_cdl == 0 || recid > 2*blk_per_trk) {
  		/* Only standard blocks so there is just one locate record. */
  		ccw[-1].flags |= CCW_FLAG_CC;
  		locate_record(ccw++, LO_data++, first_trk, first_offs + 1,
  			      last_rec - recid + 1, cmd, device, blksize);
  	}
  	rq_for_each_segment(bv, req, iter) {
  		dst = page_address(bv->bv_page) + bv->bv_offset;
  		if (dasd_page_cache) {
  			char *copy = kmem_cache_alloc(dasd_page_cache,
  						      GFP_DMA | __GFP_NOWARN);
  			if (copy && rq_data_dir(req) == WRITE)
  				memcpy(copy + bv->bv_offset, dst, bv->bv_len);
  			if (copy)
  				dst = copy + bv->bv_offset;
  		}
  		for (off = 0; off < bv->bv_len; off += blksize) {
  			sector_t trkid = recid;
  			unsigned int recoffs = sector_div(trkid, blk_per_trk);
  			rcmd = cmd;
  			count = blksize;
  			/* Locate record for cdl special block ? */
  			if (private->uses_cdl && recid < 2*blk_per_trk) {
  				if (dasd_eckd_cdl_special(blk_per_trk, recid)){
  					rcmd |= 0x8;
  					count = dasd_eckd_cdl_reclen(recid);
  					if (count < blksize &&
  					    rq_data_dir(req) == READ)
  						memset(dst + count, 0xe5,
  						       blksize - count);
  				}
  				ccw[-1].flags |= CCW_FLAG_CC;
  				locate_record(ccw++, LO_data++,
  					      trkid, recoffs + 1,
  					      1, rcmd, device, count);
  			}
  			/* Locate record for standard blocks ? */
  			if (private->uses_cdl && recid == 2*blk_per_trk) {
  				ccw[-1].flags |= CCW_FLAG_CC;
  				locate_record(ccw++, LO_data++,
  					      trkid, recoffs + 1,
  					      last_rec - recid + 1,
  					      cmd, device, count);
  			}
  			/* Read/write ccw. */
  			ccw[-1].flags |= CCW_FLAG_CC;
  			ccw->cmd_code = rcmd;
  			ccw->count = count;
  			if (idal_is_needed(dst, blksize)) {
  				ccw->cda = (__u32)(addr_t) idaws;
  				ccw->flags = CCW_FLAG_IDA;
  				idaws = idal_create_words(idaws, dst, blksize);
  			} else {
  				ccw->cda = (__u32)(addr_t) dst;
  				ccw->flags = 0;
  			}
  			ccw++;
  			dst += blksize;
  			recid++;
  		}
  	}
  	if (req->cmd_flags & REQ_FAILFAST)
  		set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
  	cqr->device = device;
  	cqr->expires = 5 * 60 * HZ;	/* 5 minutes */
  	cqr->lpm = private->path_data.ppm;
  	cqr->retries = 256;
  	cqr->buildclk = get_clock();
  	cqr->status = DASD_CQR_FILLED;
  	return cqr;
  }
  
  static int
  dasd_eckd_free_cp(struct dasd_ccw_req *cqr, struct request *req)
  {
  	struct dasd_eckd_private *private;
  	struct ccw1 *ccw;
  	struct req_iterator iter;
  	struct bio_vec *bv;
  	char *dst, *cda;
  	unsigned int blksize, blk_per_trk, off;
  	sector_t recid;
  	int status;
  
  	if (!dasd_page_cache)
  		goto out;
  	private = (struct dasd_eckd_private *) cqr->device->private;
  	blksize = cqr->device->bp_block;
  	blk_per_trk = recs_per_track(&private->rdc_data, 0, blksize);
  	recid = req->sector >> cqr->device->s2b_shift;
  	ccw = cqr->cpaddr;
  	/* Skip over define extent & locate record. */
  	ccw++;
  	if (private->uses_cdl == 0 || recid > 2*blk_per_trk)
  		ccw++;
  	rq_for_each_segment(bv, req, iter) {
  		dst = page_address(bv->bv_page) + bv->bv_offset;
  		for (off = 0; off < bv->bv_len; off += blksize) {
  			/* Skip locate record. */
  			if (private->uses_cdl && recid <= 2*blk_per_trk)
  				ccw++;
  			if (dst) {
  				if (ccw->flags & CCW_FLAG_IDA)
  					cda = *((char **)((addr_t) ccw->cda));
  				else
  					cda = (char *)((addr_t) ccw->cda);
  				if (dst != cda) {
  					if (rq_data_dir(req) == READ)
  						memcpy(dst, cda, bv->bv_len);
  					kmem_cache_free(dasd_page_cache,
  					    (void *)((addr_t)cda & PAGE_MASK));
  				}
  				dst = NULL;
  			}
  			ccw++;
  			recid++;
  		}
  	}
  out:
  	status = cqr->status == DASD_CQR_DONE;
  	dasd_sfree_request(cqr, cqr->device);
  	return status;
  }
  
  static int
  dasd_eckd_fill_info(struct dasd_device * device,
  		    struct dasd_information2_t * info)
  {
  	struct dasd_eckd_private *private;
  
  	private = (struct dasd_eckd_private *) device->private;
  	info->label_block = 2;
  	info->FBA_layout = private->uses_cdl ? 0 : 1;
  	info->format = private->uses_cdl ? DASD_FORMAT_CDL : DASD_FORMAT_LDL;
  	info->characteristics_size = sizeof(struct dasd_eckd_characteristics);
  	memcpy(info->characteristics, &private->rdc_data,
  	       sizeof(struct dasd_eckd_characteristics));
  	info->confdata_size = sizeof (struct dasd_eckd_confdata);
  	memcpy(info->configuration_data, &private->conf_data,
  	       sizeof (struct dasd_eckd_confdata));
  	return 0;
  }
  
  /*
   * SECTION: ioctl functions for eckd devices.
   */
  
  /*
   * Release device ioctl.
   * Buils a channel programm to releases a prior reserved
   * (see dasd_eckd_reserve) device.
   */
  static int
  dasd_eckd_release(struct dasd_device *device)
  {
  	struct dasd_ccw_req *cqr;
  	int rc;
  
  	if (!capable(CAP_SYS_ADMIN))
  		return -EACCES;
  
  	cqr = dasd_smalloc_request(dasd_eckd_discipline.name,
  				   1, 32, device);
  	if (IS_ERR(cqr)) {
  		DEV_MESSAGE(KERN_WARNING, device, "%s",
  			    "Could not allocate initialization request");
  		return PTR_ERR(cqr);
  	}
  	cqr->cpaddr->cmd_code = DASD_ECKD_CCW_RELEASE;
          cqr->cpaddr->flags |= CCW_FLAG_SLI;
          cqr->cpaddr->count = 32;
  	cqr->cpaddr->cda = (__u32)(addr_t) cqr->data;
  	cqr->device = device;
  	clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
  	set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
  	cqr->retries = 2;	/* set retry counter to enable basic ERP */
  	cqr->expires = 2 * HZ;
  	cqr->buildclk = get_clock();
  	cqr->status = DASD_CQR_FILLED;
  
  	rc = dasd_sleep_on_immediatly(cqr);
  
  	dasd_sfree_request(cqr, cqr->device);
  	return rc;
  }
  
  /*
   * Reserve device ioctl.
   * Options are set to 'synchronous wait for interrupt' and
   * 'timeout the request'. This leads to a terminate IO if
   * the interrupt is outstanding for a certain time.
   */
  static int
  dasd_eckd_reserve(struct dasd_device *device)
  {
  	struct dasd_ccw_req *cqr;
  	int rc;
  
  	if (!capable(CAP_SYS_ADMIN))
  		return -EACCES;
  
  	cqr = dasd_smalloc_request(dasd_eckd_discipline.name,
  				   1, 32, device);
  	if (IS_ERR(cqr)) {
  		DEV_MESSAGE(KERN_WARNING, device, "%s",
  			    "Could not allocate initialization request");
  		return PTR_ERR(cqr);
  	}
  	cqr->cpaddr->cmd_code = DASD_ECKD_CCW_RESERVE;
          cqr->cpaddr->flags |= CCW_FLAG_SLI;
          cqr->cpaddr->count = 32;
  	cqr->cpaddr->cda = (__u32)(addr_t) cqr->data;
  	cqr->device = device;
  	clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
  	set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
  	cqr->retries = 2;	/* set retry counter to enable basic ERP */
  	cqr->expires = 2 * HZ;
  	cqr->buildclk = get_clock();
  	cqr->status = DASD_CQR_FILLED;
  
  	rc = dasd_sleep_on_immediatly(cqr);
  
  	dasd_sfree_request(cqr, cqr->device);
  	return rc;
  }
  
  /*
   * Steal lock ioctl - unconditional reserve device.
   * Buils a channel programm to break a device's reservation.
   * (unconditional reserve)
   */
  static int
  dasd_eckd_steal_lock(struct dasd_device *device)
  {
  	struct dasd_ccw_req *cqr;
  	int rc;
  
  	if (!capable(CAP_SYS_ADMIN))
  		return -EACCES;
  
  	cqr = dasd_smalloc_request(dasd_eckd_discipline.name,
  				   1, 32, device);
  	if (IS_ERR(cqr)) {
  		DEV_MESSAGE(KERN_WARNING, device, "%s",
  			    "Could not allocate initialization request");
  		return PTR_ERR(cqr);
  	}
  	cqr->cpaddr->cmd_code = DASD_ECKD_CCW_SLCK;
          cqr->cpaddr->flags |= CCW_FLAG_SLI;
          cqr->cpaddr->count = 32;
  	cqr->cpaddr->cda = (__u32)(addr_t) cqr->data;
  	cqr->device = device;
  	clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
  	set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
  	cqr->retries = 2;	/* set retry counter to enable basic ERP */
  	cqr->expires = 2 * HZ;
  	cqr->buildclk = get_clock();
  	cqr->status = DASD_CQR_FILLED;
  
  	rc = dasd_sleep_on_immediatly(cqr);
  
  	dasd_sfree_request(cqr, cqr->device);
  	return rc;
  }
  
  /*
   * Read performance statistics
   */
  static int
  dasd_eckd_performance(struct dasd_device *device, void __user *argp)
  {
  	struct dasd_psf_prssd_data *prssdp;
  	struct dasd_rssd_perf_stats_t *stats;
  	struct dasd_ccw_req *cqr;
  	struct ccw1 *ccw;
  	int rc;
  
  	cqr = dasd_smalloc_request(dasd_eckd_discipline.name,
  				   1 /* PSF */  + 1 /* RSSD */ ,
  				   (sizeof (struct dasd_psf_prssd_data) +
  				    sizeof (struct dasd_rssd_perf_stats_t)),
  				   device);
  	if (IS_ERR(cqr)) {
  		DEV_MESSAGE(KERN_WARNING, device, "%s",
  			    "Could not allocate initialization request");
  		return PTR_ERR(cqr);
  	}
  	cqr->device = device;
  	cqr->retries = 0;
  	cqr->expires = 10 * HZ;
  
  	/* Prepare for Read Subsystem Data */
  	prssdp = (struct dasd_psf_prssd_data *) cqr->data;
  	memset(prssdp, 0, sizeof (struct dasd_psf_prssd_data));
  	prssdp->order = PSF_ORDER_PRSSD;
  	prssdp->suborder = 0x01;	/* Perfomance Statistics */
  	prssdp->varies[1] = 0x01;	/* Perf Statistics for the Subsystem */
  
  	ccw = cqr->cpaddr;
  	ccw->cmd_code = DASD_ECKD_CCW_PSF;
  	ccw->count = sizeof (struct dasd_psf_prssd_data);
  	ccw->flags |= CCW_FLAG_CC;
  	ccw->cda = (__u32)(addr_t) prssdp;
  
  	/* Read Subsystem Data - Performance Statistics */
  	stats = (struct dasd_rssd_perf_stats_t *) (prssdp + 1);
  	memset(stats, 0, sizeof (struct dasd_rssd_perf_stats_t));
  
  	ccw++;
  	ccw->cmd_code = DASD_ECKD_CCW_RSSD;
  	ccw->count = sizeof (struct dasd_rssd_perf_stats_t);
  	ccw->cda = (__u32)(addr_t) stats;
  
  	cqr->buildclk = get_clock();
  	cqr->status = DASD_CQR_FILLED;
  	rc = dasd_sleep_on(cqr);
  	if (rc == 0) {
  		/* Prepare for Read Subsystem Data */
  		prssdp = (struct dasd_psf_prssd_data *) cqr->data;
  		stats = (struct dasd_rssd_perf_stats_t *) (prssdp + 1);
  		if (copy_to_user(argp, stats,
  				 sizeof(struct dasd_rssd_perf_stats_t)))
  			rc = -EFAULT;
  	}
  	dasd_sfree_request(cqr, cqr->device);
  	return rc;
  }
  
  /*
   * Get attributes (cache operations)
   * Returnes the cache attributes used in Define Extend (DE).
   */
  static int
  dasd_eckd_get_attrib(struct dasd_device *device, void __user *argp)
  {
  	struct dasd_eckd_private *private =
  		(struct dasd_eckd_private *)device->private;
  	struct attrib_data_t attrib = private->attrib;
  	int rc;
  
          if (!capable(CAP_SYS_ADMIN))
                  return -EACCES;
  	if (!argp)
                  return -EINVAL;
  
  	rc = 0;
  	if (copy_to_user(argp, (long *) &attrib,
  			 sizeof (struct attrib_data_t)))
  		rc = -EFAULT;
  
  	return rc;
  }
  
  /*
   * Set attributes (cache operations)
   * Stores the attributes for cache operation to be used in Define Extend (DE).
   */
  static int
  dasd_eckd_set_attrib(struct dasd_device *device, void __user *argp)
  {
  	struct dasd_eckd_private *private =
  		(struct dasd_eckd_private *)device->private;
  	struct attrib_data_t attrib;
  
  	if (!capable(CAP_SYS_ADMIN))
  		return -EACCES;
  	if (!argp)
  		return -EINVAL;
  
  	if (copy_from_user(&attrib, argp, sizeof(struct attrib_data_t)))
  		return -EFAULT;
  	private->attrib = attrib;
  
  	DEV_MESSAGE(KERN_INFO, device,
  		    "cache operation mode set to %x (%i cylinder prestage)",
  		    private->attrib.operation, private->attrib.nr_cyl);
  	return 0;
  }
  
  static int
  dasd_eckd_ioctl(struct dasd_device *device, unsigned int cmd, void __user *argp)
  {
  	switch (cmd) {
  	case BIODASDGATTR:
  		return dasd_eckd_get_attrib(device, argp);
  	case BIODASDSATTR:
  		return dasd_eckd_set_attrib(device, argp);
  	case BIODASDPSRD:
  		return dasd_eckd_performance(device, argp);
  	case BIODASDRLSE:
  		return dasd_eckd_release(device);
  	case BIODASDRSRV:
  		return dasd_eckd_reserve(device);
  	case BIODASDSLCK:
  		return dasd_eckd_steal_lock(device);
  	default:
  		return -ENOIOCTLCMD;
  	}
  }
  
  /*
   * Dump the range of CCWs into 'page' buffer
   * and return number of printed chars.
   */
  static int
  dasd_eckd_dump_ccw_range(struct ccw1 *from, struct ccw1 *to, char *page)
  {
  	int len, count;
  	char *datap;
  
  	len = 0;
  	while (from <= to) {
  		len += sprintf(page + len, KERN_ERR PRINTK_HEADER
  			       " CCW %p: %08X %08X DAT:",
  			       from, ((int *) from)[0], ((int *) from)[1]);
  
  		/* get pointer to data (consider IDALs) */
  		if (from->flags & CCW_FLAG_IDA)
  			datap = (char *) *((addr_t *) (addr_t) from->cda);
  		else
  			datap = (char *) ((addr_t) from->cda);
  
  		/* dump data (max 32 bytes) */
  		for (count = 0; count < from->count && count < 32; count++) {
  			if (count % 8 == 0) len += sprintf(page + len, " ");
  			if (count % 4 == 0) len += sprintf(page + len, " ");
  			len += sprintf(page + len, "%02x", datap[count]);
  		}
  		len += sprintf(page + len, "\n");
  		from++;
  	}
  	return len;
  }
  
  /*
   * Print sense data and related channel program.
   * Parts are printed because printk buffer is only 1024 bytes.
   */
  static void
  dasd_eckd_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
  		     struct irb *irb)
  {
  	char *page;
  	struct ccw1 *first, *last, *fail, *from, *to;
  	int len, sl, sct;
  
  	page = (char *) get_zeroed_page(GFP_ATOMIC);
  	if (page == NULL) {
  		DEV_MESSAGE(KERN_ERR, device, " %s",
  			    "No memory to dump sense data");
  		return;
  	}
  	/* dump the sense data */
  	len = sprintf(page,  KERN_ERR PRINTK_HEADER
  		      " I/O status report for device %s:\n",
  		      device->cdev->dev.bus_id);
  	len += sprintf(page + len, KERN_ERR PRINTK_HEADER
  		       " in req: %p CS: 0x%02X DS: 0x%02X\n", req,
  		       irb->scsw.cstat, irb->scsw.dstat);
  	len += sprintf(page + len, KERN_ERR PRINTK_HEADER
  		       " device %s: Failing CCW: %p\n",
  		       device->cdev->dev.bus_id,
  		       (void *) (addr_t) irb->scsw.cpa);
  	if (irb->esw.esw0.erw.cons) {
  		for (sl = 0; sl < 4; sl++) {
  			len += sprintf(page + len, KERN_ERR PRINTK_HEADER
  				       " Sense(hex) %2d-%2d:",
  				       (8 * sl), ((8 * sl) + 7));
  
  			for (sct = 0; sct < 8; sct++) {
  				len += sprintf(page + len, " %02x",
  					       irb->ecw[8 * sl + sct]);
  			}
  			len += sprintf(page + len, "\n");
  		}
  
  		if (irb->ecw[27] & DASD_SENSE_BIT_0) {
  			/* 24 Byte Sense Data */
  			sprintf(page + len, KERN_ERR PRINTK_HEADER
  				" 24 Byte: %x MSG %x, "
  				"%s MSGb to SYSOP\n",
  				irb->ecw[7] >> 4, irb->ecw[7] & 0x0f,
  				irb->ecw[1] & 0x10 ? "" : "no");
  		} else {
  			/* 32 Byte Sense Data */
  			sprintf(page + len, KERN_ERR PRINTK_HEADER
  				" 32 Byte: Format: %x "
  				"Exception class %x\n",
  				irb->ecw[6] & 0x0f, irb->ecw[22] >> 4);
  		}
  	} else {
  		sprintf(page + len, KERN_ERR PRINTK_HEADER
  			" SORRY - NO VALID SENSE AVAILABLE\n");
  	}
  	printk("%s", page);
  
  	/* dump the Channel Program (max 140 Bytes per line) */
  	/* Count CCW and print first CCWs (maximum 1024 % 140 = 7) */
  	first = req->cpaddr;
  	for (last = first; last->flags & (CCW_FLAG_CC | CCW_FLAG_DC); last++);
  	to = min(first + 6, last);
  	len = sprintf(page,  KERN_ERR PRINTK_HEADER
  		      " Related CP in req: %p\n", req);
  	dasd_eckd_dump_ccw_range(first, to, page + len);
  	printk("%s", page);
  
  	/* print failing CCW area (maximum 4) */
  	/* scsw->cda is either valid or zero  */
  	len = 0;
  	from = ++to;
  	fail = (struct ccw1 *)(addr_t) irb->scsw.cpa; /* failing CCW */
  	if (from <  fail - 2) {
  		from = fail - 2;     /* there is a gap - print header */
  		len += sprintf(page, KERN_ERR PRINTK_HEADER "......\n");
  	}
  	to = min(fail + 1, last);
  	len += dasd_eckd_dump_ccw_range(from, to, page + len);
  
  	/* print last CCWs (maximum 2) */
  	from = max(from, ++to);
  	if (from < last - 1) {
  		from = last - 1;     /* there is a gap - print header */
  		len += sprintf(page + len, KERN_ERR PRINTK_HEADER "......\n");
  	}
  	len += dasd_eckd_dump_ccw_range(from, last, page + len);
  	if (len > 0)
  		printk("%s", page);
  	free_page((unsigned long) page);
  }
  
  /*
   * max_blocks is dependent on the amount of storage that is available
   * in the static io buffer for each device. Currently each device has
   * 8192 bytes (=2 pages). For 64 bit one dasd_mchunkt_t structure has
   * 24 bytes, the struct dasd_ccw_req has 136 bytes and each block can use
   * up to 16 bytes (8 for the ccw and 8 for the idal pointer). In
   * addition we have one define extent ccw + 16 bytes of data and one
   * locate record ccw + 16 bytes of data. That makes:
   * (8192 - 24 - 136 - 8 - 16 - 8 - 16) / 16 = 499 blocks at maximum.
   * We want to fit two into the available memory so that we can immediately
   * start the next request if one finishes off. That makes 249.5 blocks
   * for one request. Give a little safety and the result is 240.
   */
  static struct dasd_discipline dasd_eckd_discipline = {
  	.owner = THIS_MODULE,
  	.name = "ECKD",
  	.ebcname = "ECKD",
  	.max_blocks = 240,
  	.check_device = dasd_eckd_check_characteristics,
  	.do_analysis = dasd_eckd_do_analysis,
  	.fill_geometry = dasd_eckd_fill_geometry,
  	.start_IO = dasd_start_IO,
  	.term_IO = dasd_term_IO,
  	.format_device = dasd_eckd_format_device,
  	.examine_error = dasd_eckd_examine_error,
  	.erp_action = dasd_eckd_erp_action,
  	.erp_postaction = dasd_eckd_erp_postaction,
  	.build_cp = dasd_eckd_build_cp,
  	.free_cp = dasd_eckd_free_cp,
  	.dump_sense = dasd_eckd_dump_sense,
  	.fill_info = dasd_eckd_fill_info,
  	.ioctl = dasd_eckd_ioctl,
  };
  
  static int __init
  dasd_eckd_init(void)
  {
  	ASCEBC(dasd_eckd_discipline.ebcname, 4);
  	return ccw_driver_register(&dasd_eckd_driver);
  }
  
  static void __exit
  dasd_eckd_cleanup(void)
  {
  	ccw_driver_unregister(&dasd_eckd_driver);
  }
  
  module_init(dasd_eckd_init);
  module_exit(dasd_eckd_cleanup);
  