patch-2.2.19 linux/drivers/s390/block/dasd_3990_erp.c

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diff -u --new-file --recursive --exclude-from /usr/src/exclude v2.2.18/drivers/s390/block/dasd_3990_erp.c linux/drivers/s390/block/dasd_3990_erp.c
@@ -1,46 +1,31 @@
 /* 
  * File...........: linux/drivers/s390/block/dasd_3990_erp.c
- * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
- *                  Horst  Hummel    <Horst.Hummel@de.ibm.com> 
+ * Author(s)......: Horst  Hummel    <Horst.Hummel@de.ibm.com> 
+ *                  Holger Smolinski <Holger.Smolinski@de.ibm.com>
  * Bugreports.to..: <Linux390@de.ibm.com>
  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 2000
  */
 
+#include <linux/blkdev.h>
 #include <asm/ccwcache.h>
+#include <asm/idals.h>
 #include <asm/dasd.h>
+#include <asm/s390io.h>
+#include <linux/timer.h>
+#include "dasd_eckd.h"
+#include "dasd_3990_erp.h"
 
 #ifdef PRINTK_HEADER
 #undef PRINTK_HEADER
-#define PRINTK_HEADER "dasd_erp(3990)"
-#endif /* PRINTK_HEADER */
+#endif				/* PRINTK_HEADER */
+#define PRINTK_HEADER "dasd_erp(3990): "
+
 
 /*
- * DASD_3990_ERP_EXAMINE_32 
- *
- * DESCRIPTION
- *   Checks only for fatal/no/recoverable error. 
- *   A detailed examination of the sense data is done later outside
- *   the interrupt handler.
- *
- * RETURN VALUES
- *   dasd_era_none      no error 
- *   dasd_era_fatal     for all fatal (unrecoverable errors)
- *   dasd_era_recover   for recoverable others.
+ ***************************************************************************** 
+ * SECTION ERP EXAMINATION
+ ***************************************************************************** 
  */
-dasd_era_t
-dasd_3990_erp_examine_32 (char *sense)
-{
-
-	switch (sense[25]) {
-	case 0x00:
-		return dasd_era_none;
-	case 0x01:
-		return dasd_era_fatal;
-	default:
-		return dasd_era_recover;
-	}
-
-}				/* end dasd_3990_erp_examine_32 */
 
 /*
  * DASD_3990_ERP_EXAMINE_24 
@@ -52,7 +37,7 @@
  *
  *   Each bit configuration leading to an action code 2 (Exit with
  *   programming error or unusual condition indication)
- *   and 10 (disabled interface) are handled as fatal errorīs.
+ *   are handled as fatal errorīs.
  * 
  *   All other configurations are handled as recoverable errors.
  *
@@ -64,31 +49,58 @@
 dasd_3990_erp_examine_24 (char *sense)
 {
 
-	/* check for 'Command Recejct' whithout environmental data present  */
-	if (sense[0] & 0x80) {
-                if (sense[2] &0x10){
-                        return dasd_era_recover;
-                } else {
-                        return dasd_era_fatal;
-                }
-        }
-	
-        /* check for 'Invalid Track Format' whithout environmental data present  */
-	if (sense[1] & 0x40) {
-                if (sense[2] &0x10){
-                        return dasd_era_recover;
-                } else {
-                        return dasd_era_fatal;
-                }
+	/* check for 'Command Recejct' which is always a fatal error  */
+	if (sense[0] & SNS0_CMD_REJECT) {
+		if (sense[2] & SNS2_ENV_DATA_PRESENT) {
+			return dasd_era_recover;
+		} else {
+			return dasd_era_fatal;
+		}
+	}
+	/* check for 'Invalid Track Format'                           */
+	if (sense[1] & SNS1_INV_TRACK_FORMAT) {
+		if (sense[2] & SNS2_ENV_DATA_PRESENT) {
+			return dasd_era_recover;
+		} else {
+			return dasd_era_fatal;
+		}
 	}
 	/* check for 'No Record Found'                                */
-	if (sense[1] & 0x08) {
+	if (sense[1] & SNS1_NO_REC_FOUND) {
 		return dasd_era_fatal;
 	}
 	/* return recoverable for all others                          */
 	return dasd_era_recover;
 
-}				/* END dasd_3990_erp_examine_24 */
+} /* END dasd_3990_erp_examine_24 */
+
+/*
+ * DASD_3990_ERP_EXAMINE_32 
+ *
+ * DESCRIPTION
+ *   Checks only for fatal/no/recoverable error. 
+ *   A detailed examination of the sense data is done later outside
+ *   the interrupt handler.
+ *
+ * RETURN VALUES
+ *   dasd_era_none      no error 
+ *   dasd_era_fatal     for all fatal (unrecoverable errors)
+ *   dasd_era_recover   for recoverable others.
+ */
+dasd_era_t
+dasd_3990_erp_examine_32 (char *sense)
+{
+
+	switch (sense[25]) {
+	case 0x00:
+		return dasd_era_none;
+	case 0x01:
+		return dasd_era_fatal;
+	default:
+		return dasd_era_recover;
+	}
+
+}				/* end dasd_3990_erp_examine_32 */
 
 /*
  * DASD_3990_ERP_EXAMINE 
@@ -118,19 +130,1134 @@
 		return dasd_era_none;
 
 	/* distinguish between 24 and 32 byte sense data */
-	if (sense[27] & 0x80) {
+	if (sense[27] & DASD_SENSE_BIT_0) {
+
+		/* examine the 24 byte sense data */
+		return dasd_3990_erp_examine_24 (sense);
+
+	} else {
 
 		/* examine the 32 byte sense data */
 		return dasd_3990_erp_examine_32 (sense);
 
+	} /* end distinguish between 24 and 32 byte sense data */
+
+} /* END dasd_3990_erp_examine */
+
+/*
+ ***************************************************************************** 
+ * SECTION ERP HANDLING
+ ***************************************************************************** 
+ */
+/*
+ ***************************************************************************** 
+ * 24 and 32 byte sense ERP functions
+ ***************************************************************************** 
+ */
+
+/*
+ * DASD_3990_ERP_BLOCK_QUEUE 
+ *
+ * DESCRIPTION
+ *   Block the given device request queue to prevent from further
+ *   processing until the started timer has expired or an related
+ *   interrupt was received.
+ *
+ *  PARAMETER
+ *   erp                request to be blocked
+ *   expires            time to wait until restart (in seconds) 
+ *
+ * RETURN VALUES
+ *   void               
+ */
+void
+dasd_3990_erp_block_queue (ccw_req_t     *erp,
+                           unsigned long expires)
+{
+
+	dasd_device_t *device = erp->device;
+
+        DASD_MESSAGE (KERN_INFO, device,
+                      "blocking request queue for %is",
+                      (int) expires);
+
+        atomic_compare_and_swap_debug (&erp->status,
+                                       CQR_STATUS_ERROR,
+                                       CQR_STATUS_PENDING);
+
+        /* restart queue after some time */
+        device->timer.function = dasd_3990_erp_restart_queue; 
+        device->timer.data = (unsigned long) erp;
+        device->timer.expires = jiffies + (expires * HZ);
+        add_timer(&device->timer); 
+
+        /* restart queue using int handler routing - just for testing - TDB */
+        /* insert "void dasd_handle_state_change_pending (devstat_t *stat);" to dasd.h */
+//        device->timer.function = dasd_handle_state_change_pending;
+//        device->timer.data = (unsigned long) &device->dev_status;
+//        device->timer.expires = jiffies + (expires * HZ);
+//        add_timer(&device->timer); 
+
+} /* end dasd_3990_erp_block_queue */ 
+
+/*
+ * DASD_3990_ERP_RESTART_QUEUE 
+ *
+ * DESCRIPTION
+ *   Restarts request currently in status PENDING.
+ *   This has to be done if either an related interrupt has received, or 
+ *   a timer has expired.
+ *   
+ *
+ *  PARAMETER
+ *   erp                pointer to the PENDING ERP
+ *
+ * RETURN VALUES
+ *   void               
+ *
+ */
+void
+dasd_3990_erp_restart_queue (unsigned long erp)
+{
+        ccw_req_t     *cqr    = (void *) erp;
+	dasd_device_t *device = cqr->device;
+	unsigned long flags;
+        
+        /* TBD delete */
+        DASD_MESSAGE (KERN_INFO, device,
+                      "%s irq %d erp %p",
+                      "dasd_3990_erp_restart_queue entered",device->devinfo.irq, erp);
+        /* get the needed locks to modify the request queue */
+	s390irq_spin_lock_irqsave (device->devinfo.irq, 
+                                   flags);
+
+        /* 'restart' the device queue */
+        if (atomic_read(&cqr->status) == CQR_STATUS_PENDING){
+                
+                DASD_MESSAGE (KERN_INFO, device,
+                              "%s",
+                              "request queue restarted by MIH");
+
+                atomic_compare_and_swap_debug (&cqr->status,
+                                               CQR_STATUS_PENDING,
+                                               CQR_STATUS_QUEUED);
+}
+
+        /* release the lock */
+        s390irq_spin_unlock_irqrestore (device->devinfo.irq, 
+                                        flags);
+        dasd_schedule_bh();
+
+} /* end dasd_3990_erp_restart_queue */
+
+/*
+ * DASD_3990_ERP_ALTERNATE_PATH 
+ *
+ * DESCRIPTION
+ *   Repeat the operation on a different channel path.
+ *   If all alternate paths have been tried, the request is posted with a
+ *   permanent error.
+ *
+ *  PARAMETER
+ *   erp                pointer to the current ERP
+ *
+ * RETURN VALUES
+ *   erp                modified pointer to the ERP
+ *
+ */
+void
+dasd_3990_erp_alternate_path (ccw_req_t *erp)
+{
+
+	dasd_device_t *device = erp->device;
+        int irq = device->devinfo.irq;
+
+	/* dissable current channel path - this causes the use of an other 
+	   channel path if there is one.. */
+
+	DASD_MESSAGE (KERN_WARNING, device,
+                      "disable lpu %x",
+                      erp->dstat->lpum);
+
+        /* try alternate valid path */
+        erp->lpm     &= ~(erp->dstat->lpum);
+        erp->options |= DOIO_VALID_LPM;		/* use LPM for DO_IO */
+
+	if ((erp->lpm & ioinfo[irq]->opm) != 0x00) {
+
+		DASD_MESSAGE (KERN_WARNING, device,
+			"try alternate lpm %x",
+			erp->lpm);
+
+		/* reset status to queued to handle the request again... */
+		atomic_compare_and_swap_debug (&erp->status,
+                                               CQR_STATUS_ERROR,
+                                               CQR_STATUS_QUEUED);
+
+                erp->retries = 1;
+                
 	} else {
+         
+                DASD_MESSAGE (KERN_WARNING, device,
+                              "%s",      
+                              "No alternate channel path left -> "
+                              "permanent error");
+                
+                /* post request with permanent error */
+                atomic_compare_and_swap_debug (&erp->status,
+                                               CQR_STATUS_ERROR,
+                                               CQR_STATUS_FAILED);
 
-		/* examine the 24 byte sense data */
-		return dasd_3990_erp_examine_24 (sense);
+        }
+        
+} /* end dasd_3990_erp_alternate_path */
+
+/*
+ * DASD_3990_ERP_ACTION_1 
+ *
+ * DESCRIPTION
+ *   Setup ERP to do the ERP action 1 (see Reference manual).
+ *   Repeat the operation on a different channel path.
+ *   If all alternate paths have been tried, the request is posted with a
+ *   permanent error.
+ *   Note: duplex handling is not implemented (yet).
+ *
+ *  PARAMETER
+ *   erp                pointer to the current ERP
+ *
+ * RETURN VALUES
+ *   erp                pointer to the ERP
+ *
+ */
+ccw_req_t *
+dasd_3990_erp_action_1 (ccw_req_t * erp)
+{
+        
+        erp->function = dasd_3990_erp_action_1;
+        
+ //       cpcmd ("TRACE IO 153 INST INT CCW", NULL, 0);  
+
+        dasd_3990_erp_alternate_path (erp);
+
+	return erp;
+
+} /* end dasd_3990_erp_action_1 */
+
+/*
+ * DASD_3990_ERP_ACTION_4 
+ *
+ * DESCRIPTION
+ *   Setup ERP to do the ERP action 4 (see Reference manual).
+ *   Set the current request to PENDING to block the CQR queue for that device
+ *   until the state change interrupt appears.
+ *   Use a timer (20 seconds) to retry the cqr if the interrupt is still missing.
+ *
+ *  PARAMETER
+ *   sense              sense data of the actual error
+ *   erp                pointer to the current ERP
+ *
+ * RETURN VALUES
+ *   erp                pointer to the ERP
+ *
+ */
+ccw_req_t *
+dasd_3990_erp_action_4 (ccw_req_t *erp,
+			char      *sense)
+{
+	dasd_device_t *device = erp->device;
+
+        /* first time set initial retry counter and erp_function    */
+        /* and retry once without waiting for state change pending  */
+        /* interrupt (this enables easier enqueing of the cqr)      */
+        if (erp->function != dasd_3990_erp_action_4) {
+                erp->retries  = 255; /* TBD 255 */
+                erp->function = dasd_3990_erp_action_4;
+
+        } else {
+
+                if (sense[25] & 0x1D) {	/* state change pending */
+                        
+                        DASD_MESSAGE (KERN_WARNING, device,
+                                      "%s",
+                                      "waiting for state change pending "
+                                      "int");
+                        
+                        dasd_3990_erp_block_queue (erp,
+                                                   60);    /* TBD change to 30 */
+                        
+                } else {
+                        /* no state change pending - retry */
+                        printk (KERN_WARNING PRINTK_HEADER
+                                "no state change pending - retry\n");
+                        
+                        atomic_compare_and_swap_debug (&erp->status,
+                                                       CQR_STATUS_ERROR,
+                                                       CQR_STATUS_QUEUED);
+                }
+        }
+
+	return erp;
+
+} /* end dasd_3990_erp_action_4 */
+
+/*
+ ***************************************************************************** 
+ * 24 byte sense ERP functions (only)
+ ***************************************************************************** 
+ */
+
+/*
+ * DASD_3990_ERP_EQUIP_CHECK
+ *
+ * DESCRIPTION
+ *   Handles 24 byte 'Equipment Check' error.
+ *
+ * PARAMETER
+ *   erp                current erp_head
+ * RETURN VALUES
+ *   erp                new erp_head - pointer to new ERP
+ */
+ccw_req_t *
+dasd_3990_erp_equip_check (ccw_req_t * erp,
+			   char *sense)
+{
+	dasd_device_t *device = erp->device;
+
+	erp->function = dasd_3990_erp_equip_check;
+
+	if (sense[2] & SNS2_ENV_DATA_PRESENT) {
+
+		DASD_MESSAGE (KERN_WARNING, device,
+                              "%s",
+                              "Equipment Check - environmental data present");
+
+		erp = dasd_3990_erp_action_4 (erp,
+					      sense);
+	}
+
+	return erp;
+
+} /* end dasd_3990_erp_equip_check */
+
+/*
+ * DASD_3990_ERP_DATA_CHECK
+ *
+ * DESCRIPTION
+ *   Handles 24 byte 'Data Check' error.
+ *
+ * PARAMETER
+ *   erp                current erp_head
+ * RETURN VALUES
+ *   erp                new erp_head - pointer to new ERP
+ */
+ccw_req_t *
+dasd_3990_erp_data_check (ccw_req_t * erp,
+			  char *sense)
+{
+	dasd_device_t *device = erp->device;
+
+	erp->function = dasd_3990_erp_data_check;
+
+	if (sense[2] & SNS2_ENV_DATA_PRESENT) {
+                
+		DASD_MESSAGE (KERN_WARNING, device,
+                              "%s",
+                              "Uncorrectable data check recovered secondary "
+                              "addr of duplex pair");
+
+		erp = dasd_3990_erp_action_4 (erp,
+					      sense);
+	}
+
+	return erp;
+
+} /* end dasd_3990_erp_data_check */
+
+
+/*
+ * DASD_3990_ERP_INV_FORMAT
+ *
+ * DESCRIPTION
+ *   Handles 24 byte 'Invalid Track Format' error.
+ *
+ * PARAMETER
+ *   erp                current erp_head
+ * RETURN VALUES
+ *   erp                new erp_head - pointer to new ERP
+ */
+ccw_req_t *
+dasd_3990_erp_inv_format (ccw_req_t * erp,
+			  char *sense)
+{
+	dasd_device_t *device = erp->device;
+
+	erp->function = dasd_3990_erp_inv_format;
+
+	if (sense[2] & SNS2_ENV_DATA_PRESENT) {
+
+		DASD_MESSAGE (KERN_WARNING, device,
+                              "%s",
+                              "Track format error when destaging or "
+                              "staging data");
+
+		erp = dasd_3990_erp_action_4 (erp,
+					      sense);
+	}
+
+	return erp;
+
+} /* end dasd_3990_erp_inv_format */
+
+/*
+ * DASD_3990_ERP_ENV_DATA
+ *
+ * DESCRIPTION
+ *   Handles 24 byte 'Environmental-Data Present' error.
+ *
+ * PARAMETER
+ *   erp                current erp_head
+ * RETURN VALUES
+ *   erp                new erp_head - pointer to new ERP
+ */
+ccw_req_t *
+dasd_3990_erp_env_data (ccw_req_t * erp,
+			char *sense)
+{
+	dasd_device_t *device = erp->device;
+
+	erp->function = dasd_3990_erp_env_data;
+
+        DASD_MESSAGE (KERN_WARNING, device,
+                      "%s",
+                      "Environmental data present");
+
+	erp = dasd_3990_erp_action_4 (erp,
+				      sense);
+
+	return erp;
+
+}				/* end dasd_3990_erp_env_data */
+
+/*
+ * DASD_3990_ERP_INSPECT_24 
+ *
+ * DESCRIPTION
+ *   Does a detailed inspection of the 24 byte sense data
+ *   and sets up a related error recovery action.  
+ *
+ * PARAMETER
+ *   sense              sense data of the actual error
+ *   erp                pointer to the currently created default ERP
+ *
+ * RETURN VALUES
+ *   erp                pointer to the (addtitional) ERP
+ */
+ccw_req_t *
+dasd_3990_erp_inspect_24 ( ccw_req_t * erp,
+                           char *sense)
+{
+	ccw_req_t *erp_filled = NULL;
+
+	/* Check sense for ....    */
+	/* 'Equipment Check'       */
+	if ((erp_filled == NULL) &&
+	    (sense[0] & SNS0_EQUIPMENT_CHECK)) {
+		erp_filled = dasd_3990_erp_equip_check (erp,
+							sense);
+	}
+	/* 'Data Check'            */
+	if ((erp_filled == NULL) &&
+	    (sense[0] & SNS0_DATA_CHECK)) {
+		erp_filled = dasd_3990_erp_data_check (erp,
+						       sense);
+	}
+	/* 'Invalid Track Format'  */
+	if ((erp_filled == NULL) &&
+	    (sense[1] & SNS1_INV_TRACK_FORMAT)) {
+		erp_filled = dasd_3990_erp_inv_format (erp,
+						       sense);
+	}
+	/* 'Environmental Data'    */
+	if ((erp_filled == NULL) &&
+	    (sense[2] & SNS2_ENV_DATA_PRESENT)) {
+		erp_filled = dasd_3990_erp_env_data (erp,
+						     sense);
+	}
+
+	/* other (unknown/not jet implemented) error - do default ERP */
+	if (erp_filled == NULL) {
+
+                printk (KERN_WARNING PRINTK_HEADER
+                        "default ERP taken\n");
+
+		erp_filled = erp;	
+	}
+
+	return erp_filled;
+
+} /* END dasd_3990_erp_inspect_24 */
+
+/*
+ ***************************************************************************** 
+ * 32 byte sense ERP functions (only)
+ ***************************************************************************** 
+ */
+
+/*
+ * DASD_3990_ERP_ACTION_1B_32
+ *
+ * DESCRIPTION
+ *   Handles 32 byte 'Action 1B' of Single Program Action Codes.
+ *   A write operation could not be finished because of an unexpected 
+ *   condition.
+ *   The already created 'default erp' is used to get the link to 
+ *   the erp chain, but it can not be used for this recovery 
+ *   action because it contains no DE/LO data space.
+ *
+ * PARAMETER
+ *   default_erp        already created default erp.
+ *   sense              current sense data 
+ * RETURN VALUES
+ *   erp                new erp or default_erp in case of error
+ */
+ccw_req_t *
+dasd_3990_erp_action_1B_32 (ccw_req_t *default_erp,
+                            char      *sense)
+{
+	dasd_device_t  *device     = default_erp->device;
+        ccw_req_t      *cqr;
+	ccw_req_t      *erp;
+        __u32          cpa;
+	DE_eckd_data_t *DE_data;
+	char           *LO_data;   /* LO_eckd_data_t */
+        ccw1_t         *ccw;
+
+	DASD_MESSAGE (KERN_WARNING, device,
+                      "%s",
+                      "Write not finsihed because of unexpected condition");
+        
+        /* determine the original cqr */
+        cqr = default_erp; 
+        while (cqr->refers != NULL){
+                cqr = cqr->refers;
+        }
+         
+        /* determine the address of the CCW to be restarted */
+        cpa = default_erp->refers->dstat->cpa;
+                
+        if (cpa == 0) {
+                cpa = (__u32) cqr->cpaddr;
+        }
+        
+        if (cpa == 0) {
+                
+                DASD_MESSAGE (KERN_WARNING, device,
+                              "%s",
+                              "Unable to determine address of the CCW "
+                              "to be restarted");
+                
+                atomic_compare_and_swap_debug (&default_erp->status,
+                                               CQR_STATUS_FILLED,
+                                               CQR_STATUS_FAILED);
+                
+                return default_erp;
+        }
+        
+	/* Build new ERP request including DE/LO */
+	erp = dasd_alloc_request ((char *) &cqr->magic,
+                                  2 + 1,                    /* DE/LO + TIC */
+                                  sizeof (DE_eckd_data_t) +
+                                  sizeof (LO_eckd_data_t));
+	if ( !erp ) {
+                DASD_MESSAGE (KERN_WARNING, device,
+                              "%s",
+                              "Unable to allocate ERP");
+                
+                atomic_compare_and_swap_debug (&default_erp->status,
+                                               CQR_STATUS_FILLED,
+                                               CQR_STATUS_FAILED);
+                
+                return default_erp;
+	}
+        
+        /* use original DE */
+	DE_data = erp->data;
+        memcpy (DE_data, 
+                cqr->data, 
+                sizeof (DE_eckd_data_t));
+        
+        /* create LO */
+	LO_data = erp->data + sizeof (DE_eckd_data_t);
+        
+        if ((sense[3]  == 0x01) &&
+            (LO_data[1] & 0x01)   ){
+                DASD_MESSAGE (KERN_WARNING, device,
+                              "%s",
+                              "BUG - this should not happen");
+                //BUG();    /* check for read count suffixing n.a. */
+        }
+
+        LO_data[0] = sense[7];  /* operation */
+        LO_data[1] = sense[8];  /* auxiliary */
+        LO_data[2] = sense[9];  
+        LO_data[3] = sense[3];  /* count */ 
+        LO_data[4] = sense[29]; /* seek_addr.cyl */
+        LO_data[5] = sense[30]; /* seek_addr.cyl 2nd byte */
+        LO_data[7] = sense[31]; /* seek_addr.head 2nd byte */  
+
+        memcpy (&(LO_data[8]), &(sense[11]), 8);   
+
+        /* create DE ccw */    
+        ccw = erp->cpaddr;
+	memset (ccw, 0, sizeof (ccw1_t));
+	ccw->cmd_code = DASD_ECKD_CCW_DEFINE_EXTENT;
+	ccw->flags = CCW_FLAG_CC;
+	ccw->count = 16;
+	ccw->cda = (__u32) __pa (DE_data);
+
+        /* create LO ccw */    
+        ccw++;
+	memset (ccw, 0, sizeof (ccw1_t));
+	ccw->cmd_code = DASD_ECKD_CCW_LOCATE_RECORD;
+	ccw->flags = CCW_FLAG_CC;
+	ccw->count = 16;
+	ccw->cda = (__u32) __pa (LO_data);
+        
+        /* TIC to the failed ccw */
+        ccw++;
+	ccw->cmd_code = CCW_CMD_TIC;
+	ccw->cda = cpa;
+
+        /* fill erp related fields */
+        erp->function = dasd_3990_erp_action_1B_32;
+	erp->refers   = default_erp->refers;
+	erp->device   = device;
+	erp->magic    = default_erp->magic;
+	erp->lpm      = 0xFF;
+	erp->expires  = 0;
+	erp->retries  = 2;
+
+	atomic_set(&erp->status, 
+                   CQR_STATUS_FILLED);
+        
+        /* remove the default erp */
+        dasd_free_request (default_erp);
+        
+	return erp;
+        
+} /* end dasd_3990_erp_action_1B_32 */
+
+
+/*
+ * DASD_3990_ERP_INSPECT_32 
+ *
+ * DESCRIPTION
+ *   Does a detailed inspection of the 32 byte sense data
+ *   and sets up a related error recovery action.  
+ *
+ * PARAMETER
+ *   sense              sense data of the actual error
+ *   erp                pointer to the currently created default ERP
+ *
+ * RETURN VALUES
+ *   erp_filled         pointer to the ERP
+ *
+ */
+ccw_req_t *
+dasd_3990_erp_inspect_32 ( ccw_req_t *erp,
+                           char      *sense )
+{
+	dasd_device_t *device = erp->device;
+
+	erp->function = dasd_3990_erp_inspect_32;
+
+	if (sense[25] & DASD_SENSE_BIT_0) {
+
+		/* compound program action codes (byte25 bit 0 == '1') */
+                printk (KERN_WARNING PRINTK_HEADER
+                        "default ERP taken\n");
+
+	} else {
+
+		/* single program action codes (byte25 bit 0 == '0') */
+		switch (sense[25]) {
+
+		case 0x1B:	/* unexpected condition during write */
+
+                        erp = dasd_3990_erp_action_1B_32 (erp,
+                                                          sense);
+#ifdef ERP_DEBUG
+                        /* TBD */
+//                        cpcmd ("STOP", NULL, 0);
+#endif
+                        break;
+
+		case 0x1D:	/* state-change pending */
+                        DASD_MESSAGE (KERN_WARNING, device, 
+                                      "%s",
+                                      "A State change pending condition exists "
+                                      "for the subsystem or device");
+
+                        erp = dasd_3990_erp_action_4 (erp,
+                                                      sense);
+//                        cpcmd ("STOP", NULL, 0);
+			break;
+
+		default:	/* all others errors */
+			printk (KERN_WARNING PRINTK_HEADER
+			 "default ERP taken\n");
+		}
+	}
+
+	return erp;
+
+} /* end dasd_3990_erp_inspect_32 */
+
+/*
+ ***************************************************************************** 
+ * main ERP control fuctions (24 and 32 byte sense)
+ ***************************************************************************** 
+ */
+
+/*
+ * DASD_3990_ERP_INSPECT
+ *
+ * DESCRIPTION
+ *   Does a detailed inspection for sense data by calling either
+ *   the 24-byte or the 32-byte inspection routine.
+ *
+ * PARAMETER
+ *   erp                pointer to the currently created default ERP
+ * RETURN VALUES
+ *   erp_new            contens was possibly modified 
+ */
+ccw_req_t *
+dasd_3990_erp_inspect (ccw_req_t * erp)
+{
+	ccw_req_t *erp_new = NULL;
+	/* sense data are located in the refers record of the */
+	/* already set up new ERP !                           */
+	char *sense = erp->refers->dstat->ii.sense.data;
+
+	/* distinguish between 24 and 32 byte sense data */
+	if (sense[27] & DASD_SENSE_BIT_0) {
+
+		/* inspect the 24 byte sense data */
+		erp_new = dasd_3990_erp_inspect_24 (erp,
+                                                    sense);
+
+	} else {
+
+		/* inspect the 32 byte sense data */
+		erp_new = dasd_3990_erp_inspect_32 (erp,
+                                                    sense);
+
+	} /* end distinguish between 24 and 32 byte sense data */
+
+	return erp_new;
+
+} /* END dasd_3990_erp_inspect */
+
+/*
+ * DASD_3990_ERP_ADD_ERP
+ * 
+ * DESCRIPTION
+ *   This funtion adds an additional request block (ERP) to the head of
+ *   the given cqr (or erp).
+ *   This erp is initialized as an default erp (retry TIC)
+ *
+ * PARAMETER
+ *   cqr                head of the current ERP-chain (or single cqr if 
+ *                      first error)
+ * RETURN VALUES
+ *   erp                pointer to new ERP-chain head
+ */
+ccw_req_t *
+dasd_3990_erp_add_erp (ccw_req_t * cqr)
+{
+	/* allocate additional request block */
+	ccw_req_t *erp = dasd_alloc_request ((char *) &cqr->magic, 1, 0);
+	if ( !erp ) {
+		printk( KERN_WARNING PRINTK_HEADER
+			"unable to allocate ERP request\n" );
+                return NULL;
+	}
+
+	/* initialize request with default TIC to current ERP/CQR */
+	erp->cpaddr->cmd_code = CCW_CMD_TIC;
+	erp->cpaddr->cda      = ((__u32) cqr->cpaddr);
+	erp->function = dasd_3990_erp_add_erp;
+	erp->refers   = cqr;
+	erp->device   = cqr->device;
+	erp->magic    = cqr->magic;
+	erp->lpm      = 0xFF;
+	erp->expires  = 0;
+	erp->retries  = 255;
+
+	atomic_set(&erp->status, 
+                   CQR_STATUS_FILLED);
+
+	return erp;
+}
+
+/*
+ * DASD_3990_ERP_ADDITIONAL_ERP 
+ * 
+ * DESCRIPTION
+ *   An additional ERP is needed to handle the current error.
+ *   Add ERP to the head of the ERP-chain containing the ERP processing
+ *   determined based on the sense data.
+ *
+ * PARAMETER
+ *   cqr                head of the current ERP-chain (or single cqr if 
+ *                      first error)
+ *
+ * RETURN VALUES
+ *   erp                pointer to new ERP-chain head
+ */
+ccw_req_t *
+dasd_3990_erp_additional_erp (ccw_req_t * cqr)
+{
+
+	ccw_req_t *erp = NULL;
+
+	/* add erp and initialize with default TIC */
+	erp = dasd_3990_erp_add_erp (cqr);
+
+	/* inspect sense, determine specific ERP if possible */
+	erp = dasd_3990_erp_inspect (erp);
+
+	return erp;
+
+}				/* end dasd_3990_erp_additional_erp */
+
+/*
+ * DASD_3990_ERP_ERROR_MATCH
+ *
+ * DESCRIPTION
+ *   check if the the device status of the given cqr is the same.
+ *   This means that the failed CCW and the relevant sense data
+ *   must match.
+ *   I don't distinguish between 24 and 32 byte sense becaus in case of
+ *   24 byte sense byte 25 and 27 is set as well.
+ *
+ * PARAMETER
+ *   cqr1               first cqr, which will be compared with the 
+ *   cqr2               second cqr.
+ *
+ * RETURN VALUES
+ *   match              'boolean' for match found
+ *                      returns 1 if match found, otherwise 0.
+ */
+int
+dasd_3990_erp_error_match (ccw_req_t * cqr1,
+			   ccw_req_t * cqr2)
+{
+	/* check failed CCW */
+	if (cqr1->dstat->cpa !=
+	    cqr2->dstat->cpa) {
+		return 0;	/* CCW doesn't match */
+
+	}
+	/* check sense data; byte 0-2,25,27 */
+	if (!((strncmp (cqr1->dstat->ii.sense.data,
+			cqr2->dstat->ii.sense.data,
+			3) == 0) &&
+	      (cqr1->dstat->ii.sense.data[27] ==
+	       cqr2->dstat->ii.sense.data[27]   ) &&
+	      (cqr1->dstat->ii.sense.data[25] ==
+	       cqr2->dstat->ii.sense.data[25]   )   )) {
+
+		return 0;	/* sense doesn't match */
+	}
+	return 1;		/* match */
+
+}				/* end dasd_3990_erp_error_match */
+
+/*
+ * DASD_3990_ERP_IN_ERP
+ *
+ * DESCRIPTION
+ *   check if the current error already happened before.
+ *   quick exit if current cqr is not an ERP (cqr->refers=NULL)
+ *
+ * PARAMETER
+ *   cqr                failed cqr (either original cqr or already an erp)
+ *
+ * RETURN VALUES
+ *   erp                erp-pointer to the already defined error recovery procedure OR
+ *                      NULL if a 'new' error occured.
+ */
+ccw_req_t *
+dasd_3990_erp_in_erp (ccw_req_t * cqr)
+{
+	ccw_req_t *erp_head = cqr,	/* save erp chain head */
+	         *erp_match = NULL;	/* save erp chain head */
+	int match = 0;		/* 'boolean' for matching error found */
+
+	if (cqr->refers == NULL) {	/* return if not in erp */
+		return NULL;
+	}
+	/* check the erp/cqr chain for current error */
+	do {
+		match = dasd_3990_erp_error_match (erp_head,
+						   cqr->refers);
+		erp_match = cqr;	/* save possible matching erp  */
+		cqr = cqr->refers;	/* check next erp/cqr in queue */
+	} while ((cqr->refers != NULL) &&
+		 (match == 0));
+
+	if (match) {
+                /* TBD */
+                printk(KERN_WARNING PRINTK_HEADER 
+                       "dasd_3990_erp_in_erp: return matching erp\n");
+		return erp_match;	/* retrun address of matching erp */
+	} else {
+                printk(KERN_WARNING PRINTK_HEADER 
+                       "dasd_3990_erp_in_erp: return no match\n");
+		return NULL;	/* return NULL to indicate that no match
+				   was found */
+	}
+
+}				/* END dasd_3990_erp_in_erp */
+
+/*
+ * DASD_3990_ERP_FURTHER_ERP (24 & 32 byte sense)
+ *
+ * DESCRIPTION
+ *   No retry is left for the current ERP. Check what has to be done 
+ *   with the ERP.
+ *     - do further defined ERP action or
+ *     - wait for interrupt or  
+ *     - exit with permanent error
+ *
+ * PARAMETER
+ *   erp                ERP which is in progress wiht no retry left
+ *
+ * RETURN VALUES
+ *   erp                modified/additional ERP
+ */
+ccw_req_t *
+dasd_3990_erp_further_erp (ccw_req_t * erp)
+{
+        dasd_device_t     *device = erp->device;
+        
+        /* check for 24 byte sense ERP */
+	if ((erp->function == dasd_3990_erp_action_1) ||
+            (erp->function == dasd_3990_erp_action_4)   ){
+                
+                erp = dasd_3990_erp_action_1 (erp);
+                
+	} else {
+                /* no retry left and no additional special handling necessary */
+                DASD_MESSAGE (KERN_WARNING, device,
+                              "no retries left for erp %p - "
+                              "set status to FAILED",
+                              erp);
+
+		atomic_compare_and_swap_debug (&erp->status,
+                                               CQR_STATUS_ERROR,
+                                               CQR_STATUS_FAILED);
+	}
+
+	return erp; 
+
+} /* end dasd_3990_erp_further_erp */
+
+/*
+ * DASD_3990_ERP_HANDLE_MATCH_ERP 
+ *
+ * DESCRIPTION
+ *   An error occured again and an ERP has been detected which is already
+ *   used to handle this error (e.g. retries). 
+ *   All prior ERP's are set to status DONE and the retry counter is
+ *   decremented.
+ *   If retry counter is already 0, it has to checked if further action
+ *   is needed (besides retry) or if the ERP has failed.
+ *
+ * PARAMETER
+ *   erp_head           first ERP in ERP-chain
+ *   erp_match          ERP that handles the actual error.
+ *
+ * RETURN VALUES
+ *   none                
+ */
+void
+dasd_3990_erp_handle_match_erp (ccw_req_t * erp_head,
+				ccw_req_t * erp_match)
+{
+
+	dasd_device_t *device   = erp_head->device;
+	ccw_req_t     *erp_done = erp_head;
+
+	/* loop over successful ERPs and remove them from chanq */
+	while ((erp_done != erp_match) &&
+	       (erp_done != NULL)) {
+
+#ifdef ERP_DEBUG
+		printk (KERN_WARNING PRINTK_HEADER
+			"successful ERP - dequeue and free request %p\n",
+			(void *) erp_done);
+#endif
+		atomic_compare_and_swap_debug (&erp_done->status,
+                                               CQR_STATUS_ERROR,
+                                               CQR_STATUS_DONE);
+
+		/* remove the request from the device queue */
+		dasd_chanq_deq (&device->queue,
+				erp_done);
+
+		/* free the finished erp request */
+		dasd_free_request (erp_done);
+
+		erp_done = erp_done->refers;
+	}
+
+	if (erp_done == NULL) 	/* erp_done should never be NULL! */
+		panic (PRINTK_HEADER "Programming error in ERP! The original "
+                       "request was lost\n");
+
+#ifdef ERP_DEBUG
+	/* handle matching ERP */
+        printk (KERN_WARNING PRINTK_HEADER
+                "handle matching erp %p\n",
+                (void *) erp_done);
+#endif
+        
+        if (erp_done->retries > 0) {
+                
+                /* check for special retries */
+                if (erp_done->function == dasd_3990_erp_action_4) {
+                        char *sense = erp_done->dstat->ii.sense.data;
+                        erp_done = dasd_3990_erp_action_4 (erp_done,
+                                                           sense);
+                        
+                } else {
+                        /* simple retry   */
+                        printk (KERN_WARNING PRINTK_HEADER
+                                "%i retries left for erp %p\n",
+                                erp_done->retries,
+                                (void *) erp_done);
+                        
+                        /* handle the request again... */
+                        atomic_compare_and_swap_debug (&erp_done->status,
+                                                       CQR_STATUS_ERROR,
+                                                       CQR_STATUS_QUEUED);
+                }
+        } else {
+                /* no retry left - check for further necessary action    */
+                /* if no further actions, handle rest as permanent error */
+                erp_done = dasd_3990_erp_further_erp (erp_done);
+	}
+
+        erp_head = erp_done;
+
+} /* end dasd_3990_erp_handle_match_erp */
+
+/*
+ * DASD_3990_ERP_ACTION
+ *
+ * DESCRIPTION
+ *   controll routine for 3990 erp actions.
+ *   Has to be called with the queue lock (namely the s390_irq_lock) acquired.
+ *
+ * PARAMETER
+ *   cqr                failed cqr (either original cqr or already an erp)
+ *
+ * RETURN VALUES
+ *   erp                erp-pointer to the head of the ERP action chain.
+ *                      This means:
+ *                       - either a ptr to an additional ERP cqr or
+ *                       - the original given cqr (which's status might be modified)
+ */
+ccw_req_t *
+dasd_3990_erp_action (ccw_req_t *cqr)
+{
+	ccw_req_t *erp = NULL;
+	dasd_device_t *device = cqr->device;
+
+#ifdef ERP_DEBUG 
+
+	printk (KERN_WARNING PRINTK_HEADER
+		"entering 3990 ERP for "
+		"0x%04X on sch %d = /dev/%s \n",
+		device->devinfo.devno,
+		device->devinfo.irq,
+		device->name);
+
+	/* print current erp_chain */
+        printk(KERN_WARNING PRINTK_HEADER 
+               "ERP chain at BEGINNING of ERP-ACTION\n");
+        {
+                ccw_req_t *temp_erp = NULL;
+                for (temp_erp = cqr; temp_erp != NULL; temp_erp = temp_erp->refers){
+                        printk(KERN_WARNING PRINTK_HEADER 
+                               "      erp %p refers to %p \n",
+                               temp_erp,
+                               temp_erp->refers);
+                }
+        } 
+#endif
+
+	/* double-check if current erp/cqr was successfull */
+	if ((cqr->dstat->cstat == 0x00) &&
+	    (cqr->dstat->dstat == (DEV_STAT_CHN_END | DEV_STAT_DEV_END))) {
+                DASD_MESSAGE (KERN_WARNING, device,
+                              "ERP called for successful request %p"
+                              " - NO ERP necessary",
+                              cqr);
+                
+                atomic_compare_and_swap_debug (&erp->status,
+                                               CQR_STATUS_ERROR,
+                                               CQR_STATUS_DONE);
+
+		return cqr;
+	}
+	/* check if sense data are available */
+	if (!cqr->dstat->ii.sense.data) {
+		DASD_MESSAGE (KERN_WARNING, device,
+			"ERP called witout sense data avail ..."
+			"request %p - NO ERP possible",
+			cqr);
+
+                atomic_compare_and_swap_debug (&erp->status,
+                                               CQR_STATUS_ERROR,
+                                               CQR_STATUS_FAILED);
+
+		return cqr; 
+
+	}
+
+	/* check if error happened before */
+	erp = dasd_3990_erp_in_erp (cqr);
+
+	if (erp == NULL) {
+		/* no matching erp found - set up erp */
+		erp = dasd_3990_erp_additional_erp (cqr);
+	} else {
+		/* matching erp found - set all leading erp's to DONE */
+		dasd_3990_erp_handle_match_erp (cqr, erp);
+		erp = cqr;
+	}
+
+#ifdef ERP_DEBUG
+	/* print current erp_chain */
+        printk(KERN_WARNING PRINTK_HEADER 
+               "ERP chain at END of ERP-ACTION\n");
+        {
+                ccw_req_t *temp_erp = NULL;
+                for (temp_erp = erp; temp_erp != NULL; temp_erp = temp_erp->refers){
+                        printk(KERN_WARNING PRINTK_HEADER 
+                               "      erp %p refers to %p \n",
+                               temp_erp,
+                               temp_erp->refers);
+                }
+        }
+#endif
 
-	}			/* end distinguish between 24 and 32 byte sense data */
+	return erp;
 
-}				/* END dasd_3990_erp_examine */
+} /* end dasd_3990_erp_action */
 
 /*
  * Overrides for Emacs so that we follow Linus's tabbing style.

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)