xref: /src/sys/dev/raidframe/rf_driver.c

/*	$NetBSD: rf_driver.c,v 1.5 1999/01/26 04:40:03 oster Exp $	*/
/*
 * Copyright (c) 1995 Carnegie-Mellon University.
 * All rights reserved.
 *
 * Author: Mark Holland, Khalil Amiri, Claudson Bornstein, William V. Courtright II,
 *         Robby Findler, Daniel Stodolsky, Rachad Youssef, Jim Zelenka
 *
 * Permission to use, copy, modify and distribute this software and
 * its documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 *
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 *
 * Carnegie Mellon requests users of this software to return to
 *
 *  Software Distribution Coordinator  or  Software.Distribution (at) CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 *
 * any improvements or extensions that they make and grant Carnegie the
 * rights to redistribute these changes.
 */

/******************************************************************************
 *
 * rf_driver.c -- main setup, teardown, and access routines for the RAID driver
 *
 * all routines are prefixed with rf_ (raidframe), to avoid conficts.
 *
 ******************************************************************************/


#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/ioctl.h>
#include <sys/fcntl.h>
#include <sys/vnode.h>


#include "rf_archs.h"
#include "rf_threadstuff.h"

#include <sys/errno.h>

#include "rf_raid.h"
#include "rf_dag.h"
#include "rf_aselect.h"
#include "rf_diskqueue.h"
#include "rf_parityscan.h"
#include "rf_alloclist.h"
#include "rf_threadid.h"
#include "rf_dagutils.h"
#include "rf_utils.h"
#include "rf_etimer.h"
#include "rf_acctrace.h"
#include "rf_configure.h"
#include "rf_general.h"
#include "rf_desc.h"
#include "rf_states.h"
#include "rf_freelist.h"
#include "rf_decluster.h"
#include "rf_map.h"
#include "rf_diskthreads.h"
#include "rf_revent.h"
#include "rf_callback.h"
#include "rf_engine.h"
#include "rf_memchunk.h"
#include "rf_mcpair.h"
#include "rf_nwayxor.h"
#include "rf_debugprint.h"
#include "rf_copyback.h"
#if !defined(__NetBSD__)
#include "rf_camlayer.h"
#endif
#include "rf_driver.h"
#include "rf_options.h"
#include "rf_shutdown.h"
#include "rf_sys.h"
#include "rf_cpuutil.h"

#include <sys/buf.h>

#if DKUSAGE > 0
#include <sys/dkusage.h>
#include <io/common/iotypes.h>
#include <io/cam/dec_cam.h>
#include <io/cam/cam.h>
#include <io/cam/pdrv.h>
#endif /* DKUSAGE > 0 */

/* rad == RF_RaidAccessDesc_t */
static RF_FreeList_t *rf_rad_freelist;
#define RF_MAX_FREE_RAD 128
#define RF_RAD_INC       16
#define RF_RAD_INITIAL   32

/* debug variables */
char rf_panicbuf[2048];       /* a buffer to hold an error msg when we panic */

/* main configuration routines */
static int raidframe_booted = 0;

static void rf_ConfigureDebug(RF_Config_t *cfgPtr);
static void set_debug_option(char *name, long val);
static void rf_UnconfigureArray(void);
static int init_rad(RF_RaidAccessDesc_t *);
static void clean_rad(RF_RaidAccessDesc_t *);
static void rf_ShutdownRDFreeList(void *);
static int rf_ConfigureRDFreeList(RF_ShutdownList_t **);


RF_DECLARE_MUTEX(rf_printf_mutex)          /* debug only:  avoids interleaved printfs by different stripes */
RF_DECLARE_GLOBAL_THREADID                 /* declarations for threadid.h */


#define SIGNAL_QUIESCENT_COND(_raid_)  wakeup(&((_raid_)->accesses_suspended))
#define WAIT_FOR_QUIESCENCE(_raid_) \
	tsleep(&((_raid_)->accesses_suspended),PRIBIO|PCATCH,"raidframe quiesce", 0);

#if DKUSAGE > 0
#define IO_BUF_ERR(bp, err, unit) { \
	bp->b_flags |= B_ERROR; \
	bp->b_resid = bp->b_bcount; \
	bp->b_error = err; \
	RF_DKU_END_IO(unit, bp); \
	biodone(bp); \
}
#else
#define IO_BUF_ERR(bp, err, unit) { \
	bp->b_flags |= B_ERROR; \
	bp->b_resid = bp->b_bcount; \
	bp->b_error = err; \
	RF_DKU_END_IO(unit); \
	biodone(bp); \
}
#endif /* DKUSAGE > 0 */

static int configureCount=0;         /* number of active configurations */
static int isconfigged=0;            /* is basic raidframe (non per-array) stuff configged */
RF_DECLARE_STATIC_MUTEX(configureMutex) /* used to lock the configuration stuff */

static RF_ShutdownList_t *globalShutdown; /* non array-specific stuff */

static int rf_ConfigureRDFreeList(RF_ShutdownList_t **listp);

/* called at system boot time */
int rf_BootRaidframe()
{
  int rc;

  if (raidframe_booted)
    return(EBUSY);
  raidframe_booted = 1;

#if RF_DEBUG_ATOMIC > 0
  rf_atent_init();
#endif /* RF_DEBUG_ATOMIC > 0 */

  rf_setup_threadid();
  rf_assign_threadid();

  rc = rf_mutex_init(&configureMutex);
  if (rc) {
    RF_ERRORMSG3("Unable to init mutex file %s line %d rc=%d\n", __FILE__,
      __LINE__, rc);
    RF_PANIC();
  }
  configureCount = 0;
  isconfigged = 0;
  globalShutdown = NULL;
  return(0);
}

/*
 * This function is really just for debugging user-level stuff: it
 * frees up all memory, other RAIDframe resources which might otherwise
 * be kept around. This is used with systems like "sentinel" to detect
 * memory leaks.
 */
int rf_UnbootRaidframe()
{
	int rc;

	RF_LOCK_MUTEX(configureMutex);
	if (configureCount) {
		RF_UNLOCK_MUTEX(configureMutex);
		return(EBUSY);
	}
	raidframe_booted = 0;
	RF_UNLOCK_MUTEX(configureMutex);
	rc = rf_mutex_destroy(&configureMutex);
	if (rc) {
		RF_ERRORMSG3("Unable to destroy mutex file %s line %d rc=%d\n", __FILE__,
			__LINE__, rc);
		RF_PANIC();
	}
#if RF_DEBUG_ATOMIC > 0
	rf_atent_shutdown();
#endif /* RF_DEBUG_ATOMIC > 0 */
	return(0);
}

/*
 * Called whenever an array is shutdown
 */
static void rf_UnconfigureArray()
{
  int rc;

  RF_LOCK_MUTEX(configureMutex);
  if (--configureCount == 0) {              /* if no active configurations, shut everything down */
    isconfigged = 0;

    rc = rf_ShutdownList(&globalShutdown);
    if (rc) {
      RF_ERRORMSG1("RAIDFRAME: unable to do global shutdown, rc=%d\n", rc);
    }

    rf_shutdown_threadid();

    /*
     * We must wait until now, because the AllocList module
     * uses the DebugMem module.
     */
    if (rf_memDebug)
      rf_print_unfreed();
  }
  RF_UNLOCK_MUTEX(configureMutex);
}

/*
 * Called to shut down an array.
 */
int rf_Shutdown(raidPtr)
  RF_Raid_t   *raidPtr;
{
  int r,c;

  struct proc *p;

  if (!raidPtr->valid) {
    RF_ERRORMSG("Attempt to shut down unconfigured RAIDframe driver.  Aborting shutdown\n");
    return(EINVAL);
  }

  /*
   * wait for outstanding IOs to land
   * As described in rf_raid.h, we use the rad_freelist lock
   * to protect the per-array info about outstanding descs
   * since we need to do freelist locking anyway, and this
   * cuts down on the amount of serialization we've got going
   * on.
   */
  RF_FREELIST_DO_LOCK(rf_rad_freelist);
  if (raidPtr->waitShutdown) {
    RF_FREELIST_DO_UNLOCK(rf_rad_freelist);
    return(EBUSY);
  }
  raidPtr->waitShutdown = 1;
  while (raidPtr->nAccOutstanding) {
    RF_WAIT_COND(raidPtr->outstandingCond, RF_FREELIST_MUTEX_OF(rf_rad_freelist));
  }
  RF_FREELIST_DO_UNLOCK(rf_rad_freelist);

  raidPtr->valid = 0;


  /* We take this opportunity to close the vnodes like we should.. */

  p = raidPtr->proc; /* XXX */

  for(r=0;r<raidPtr->numRow;r++) {
	  for(c=0;c<raidPtr->numCol;c++) {
		  printf("Closing vnode for row: %d col: %d\n",r,c);
		  if (raidPtr->raid_cinfo[r][c].ci_vp) {
			  (void)vn_close(raidPtr->raid_cinfo[r][c].ci_vp,
					 FREAD|FWRITE,  p->p_ucred, p);
		  } else {
			  printf("vnode was NULL\n");
		  }

	  }
  }
  for(r=0;r<raidPtr->numSpare;r++) {
	  printf("Closing vnode for spare: %d\n",r);
	  if (raidPtr->raid_cinfo[0][raidPtr->numCol+r].ci_vp) {
		  (void)vn_close(raidPtr->raid_cinfo[0][raidPtr->numCol+r].ci_vp,
				 FREAD|FWRITE,  p->p_ucred, p);
	  } else {
		  printf("vnode was NULL\n");
	  }
  }



  rf_ShutdownList(&raidPtr->shutdownList);

  rf_UnconfigureArray();

  return(0);
}

#define DO_INIT_CONFIGURE(f) { \
	rc = f (&globalShutdown); \
	if (rc) { \
		RF_ERRORMSG2("RAIDFRAME: failed %s with %d\n", RF_STRING(f), rc); \
		rf_ShutdownList(&globalShutdown); \
		configureCount--; \
		RF_UNLOCK_MUTEX(configureMutex); \
		return(rc); \
	} \
}

#define DO_RAID_FAIL() { \
	rf_ShutdownList(&raidPtr->shutdownList); \
	rf_UnconfigureArray(); \
}

#define DO_RAID_INIT_CONFIGURE(f) { \
	rc = f (&raidPtr->shutdownList, raidPtr, cfgPtr); \
	if (rc) { \
		RF_ERRORMSG2("RAIDFRAME: failed %s with %d\n", RF_STRING(f), rc); \
		DO_RAID_FAIL(); \
		return(rc); \
	} \
}

#define DO_RAID_MUTEX(_m_) { \
	rc = rf_create_managed_mutex(&raidPtr->shutdownList, (_m_)); \
	if (rc) { \
		RF_ERRORMSG3("Unable to init mutex file %s line %d rc=%d\n", \
			__FILE__, __LINE__, rc); \
		DO_RAID_FAIL(); \
		return(rc); \
	} \
}

#define DO_RAID_COND(_c_) { \
	rc = rf_create_managed_cond(&raidPtr->shutdownList, (_c_)); \
	if (rc) { \
		RF_ERRORMSG3("Unable to init cond file %s line %d rc=%d\n", \
			__FILE__, __LINE__, rc); \
		DO_RAID_FAIL(); \
		return(rc); \
	} \
}

int rf_Configure(raidPtr, cfgPtr)
  RF_Raid_t    *raidPtr;
  RF_Config_t  *cfgPtr;
{
  RF_RowCol_t row, col;
  int i, rc;
  int unit;
  struct proc *p;

  if (raidPtr->valid) {
    RF_ERRORMSG("RAIDframe configuration not shut down.  Aborting configure.\n");
    return(EINVAL);
  }

  RF_LOCK_MUTEX(configureMutex);
  configureCount++;
  if (isconfigged == 0) {
    rc = rf_create_managed_mutex(&globalShutdown, &rf_printf_mutex);
    if (rc) {
      RF_ERRORMSG3("Unable to init mutex file %s line %d rc=%d\n", __FILE__,
        __LINE__, rc);
      rf_ShutdownList(&globalShutdown);
      return(rc);
    }

    /* initialize globals */
    printf("RAIDFRAME: protectedSectors is %ld\n",rf_protectedSectors);

    rf_clear_debug_print_buffer();

    DO_INIT_CONFIGURE(rf_ConfigureAllocList);
    DO_INIT_CONFIGURE(rf_ConfigureEtimer);
    /*
     * Yes, this does make debugging general to the whole system instead
     * of being array specific. Bummer, drag.
     */
    rf_ConfigureDebug(cfgPtr);
    DO_INIT_CONFIGURE(rf_ConfigureDebugMem);
    DO_INIT_CONFIGURE(rf_ConfigureAccessTrace);
    DO_INIT_CONFIGURE(rf_ConfigureMapModule);
    DO_INIT_CONFIGURE(rf_ConfigureReconEvent);
    DO_INIT_CONFIGURE(rf_ConfigureCallback);
    DO_INIT_CONFIGURE(rf_ConfigureMemChunk);
    DO_INIT_CONFIGURE(rf_ConfigureRDFreeList);
    DO_INIT_CONFIGURE(rf_ConfigureNWayXor);
    DO_INIT_CONFIGURE(rf_ConfigureStripeLockFreeList);
    DO_INIT_CONFIGURE(rf_ConfigureMCPair);
#if !defined(__NetBSD__)
    DO_INIT_CONFIGURE(rf_ConfigureCamLayer);
#endif
    DO_INIT_CONFIGURE(rf_ConfigureDAGs);
    DO_INIT_CONFIGURE(rf_ConfigureDAGFuncs);
    DO_INIT_CONFIGURE(rf_ConfigureDebugPrint);
    DO_INIT_CONFIGURE(rf_ConfigureReconstruction);
    DO_INIT_CONFIGURE(rf_ConfigureCopyback);
    DO_INIT_CONFIGURE(rf_ConfigureDiskQueueSystem);
    DO_INIT_CONFIGURE(rf_ConfigureCpuMonitor);
    isconfigged = 1;
  }
  RF_UNLOCK_MUTEX(configureMutex);

  /*
   * Null out the entire raid descriptor to avoid problems when we reconfig.
   * This also clears the valid bit.
   */
  /* XXX this clearing should be moved UP to outside of here.... that, or
     rf_Configure() needs to take more arguments... XXX */
  unit = raidPtr->raidid;
  p = raidPtr->proc;   /* XXX save these... */
  bzero((char *)raidPtr, sizeof(RF_Raid_t));
  raidPtr->raidid = unit;
  raidPtr->proc = p;   /* XXX and then recover them..*/
  DO_RAID_MUTEX(&raidPtr->mutex);
  /* set up the cleanup list.  Do this after ConfigureDebug so that value of memDebug will be set */

  rf_MakeAllocList(raidPtr->cleanupList);
  if (raidPtr->cleanupList == NULL) {
    DO_RAID_FAIL();
    return(ENOMEM);
  }

  rc = rf_ShutdownCreate(&raidPtr->shutdownList,
			 (void (*)(void *))rf_FreeAllocList,
			 raidPtr->cleanupList);
  if (rc) {
    RF_ERRORMSG3("Unable to add to shutdown list file %s line %d rc=%d\n",
      __FILE__, __LINE__, rc);
    DO_RAID_FAIL();
    return(rc);
  }

  raidPtr->numRow = cfgPtr->numRow;
  raidPtr->numCol = cfgPtr->numCol;
  raidPtr->numSpare = cfgPtr->numSpare;

  /* XXX we don't even pretend to support more than one row
     in the kernel... */
  if (raidPtr->numRow != 1) {
	  RF_ERRORMSG("Only one row supported in kernel.\n");
	  DO_RAID_FAIL();
	  return(EINVAL);
  }



  RF_CallocAndAdd(raidPtr->status, raidPtr->numRow, sizeof(RF_RowStatus_t),
    (RF_RowStatus_t *), raidPtr->cleanupList);
  if (raidPtr->status == NULL) {
    DO_RAID_FAIL();
    return(ENOMEM);
  }

  RF_CallocAndAdd(raidPtr->reconControl, raidPtr->numRow,
    sizeof(RF_ReconCtrl_t *), (RF_ReconCtrl_t **), raidPtr->cleanupList);
  if (raidPtr->reconControl == NULL) {
    DO_RAID_FAIL();
    return(ENOMEM);
  }
  for (i=0; i<raidPtr->numRow; i++) {
    raidPtr->status[i] = rf_rs_optimal;
    raidPtr->reconControl[i] = NULL;
  }

  DO_RAID_INIT_CONFIGURE(rf_ConfigureEngine);
  DO_RAID_INIT_CONFIGURE(rf_ConfigureStripeLocks);

  DO_RAID_COND(&raidPtr->outstandingCond);

  raidPtr->nAccOutstanding = 0;
  raidPtr->waitShutdown = 0;

  DO_RAID_MUTEX(&raidPtr->access_suspend_mutex);
  DO_RAID_COND(&raidPtr->quiescent_cond);

  DO_RAID_COND(&raidPtr->waitForReconCond);

  DO_RAID_MUTEX(&raidPtr->recon_done_proc_mutex);
  DO_RAID_INIT_CONFIGURE(rf_ConfigureDisks);
  DO_RAID_INIT_CONFIGURE(rf_ConfigureSpareDisks);
  /* do this after ConfigureDisks & ConfigureSpareDisks to be sure dev no. is set */
  DO_RAID_INIT_CONFIGURE(rf_ConfigureDiskQueues);

  DO_RAID_INIT_CONFIGURE(rf_ConfigureLayout);

  DO_RAID_INIT_CONFIGURE(rf_ConfigurePSStatus);

  for(row=0;row<raidPtr->numRow;row++) {
    for(col=0;col<raidPtr->numCol;col++) {
      /*
       * XXX better distribution
       */
      raidPtr->hist_diskreq[row][col] = 0;
    }
  }

  if (rf_keepAccTotals) {
    raidPtr->keep_acc_totals = 1;
  }

  rf_StartUserStats(raidPtr);

  raidPtr->valid = 1;
  return(0);
}

static int init_rad(desc)
  RF_RaidAccessDesc_t  *desc;
{
	int rc;

	rc = rf_mutex_init(&desc->mutex);
	if (rc) {
		RF_ERRORMSG3("Unable to init mutex file %s line %d rc=%d\n", __FILE__,
			__LINE__, rc);
		return(rc);
	}
	rc = rf_cond_init(&desc->cond);
	if (rc) {
		RF_ERRORMSG3("Unable to init cond file %s line %d rc=%d\n", __FILE__,
			__LINE__, rc);
		rf_mutex_destroy(&desc->mutex);
		return(rc);
	}
	return(0);
}

static void clean_rad(desc)
  RF_RaidAccessDesc_t  *desc;
{
	rf_mutex_destroy(&desc->mutex);
	rf_cond_destroy(&desc->cond);
}

static void rf_ShutdownRDFreeList(ignored)
  void  *ignored;
{
	RF_FREELIST_DESTROY_CLEAN(rf_rad_freelist,next,(RF_RaidAccessDesc_t *),clean_rad);
}

static int rf_ConfigureRDFreeList(listp)
  RF_ShutdownList_t **listp;
{
	int rc;

	RF_FREELIST_CREATE(rf_rad_freelist, RF_MAX_FREE_RAD,
		RF_RAD_INC, sizeof(RF_RaidAccessDesc_t));
	if (rf_rad_freelist == NULL) {
		return(ENOMEM);
	}
	rc = rf_ShutdownCreate(listp, rf_ShutdownRDFreeList, NULL);
	if (rc) {
		RF_ERRORMSG3("Unable to add to shutdown list file %s line %d rc=%d\n", __FILE__,
			__LINE__, rc);
		rf_ShutdownRDFreeList(NULL);
		return(rc);
	}
	RF_FREELIST_PRIME_INIT(rf_rad_freelist, RF_RAD_INITIAL,next,
		(RF_RaidAccessDesc_t *),init_rad);
	return(0);
}

RF_RaidAccessDesc_t *rf_AllocRaidAccDesc(
  RF_Raid_t                    *raidPtr,
  RF_IoType_t                   type,
  RF_RaidAddr_t                 raidAddress,
  RF_SectorCount_t              numBlocks,
  caddr_t                       bufPtr,
  void                         *bp,
  RF_DagHeader_t              **paramDAG,
  RF_AccessStripeMapHeader_t  **paramASM,
  RF_RaidAccessFlags_t          flags,
  void                        (*cbF)(struct buf *),
  void                         *cbA,
  RF_AccessState_t             *states)
{
  RF_RaidAccessDesc_t *desc;

  RF_FREELIST_GET_INIT_NOUNLOCK(rf_rad_freelist,desc,next,(RF_RaidAccessDesc_t *),init_rad);
  if (raidPtr->waitShutdown) {
    /*
     * Actually, we're shutting the array down. Free the desc
     * and return NULL.
     */
    RF_FREELIST_DO_UNLOCK(rf_rad_freelist);
    RF_FREELIST_FREE_CLEAN(rf_rad_freelist,desc,next,clean_rad);
    return(NULL);
  }
  raidPtr->nAccOutstanding++;
  RF_FREELIST_DO_UNLOCK(rf_rad_freelist);

  desc->raidPtr     = (void*)raidPtr;
  desc->type        = type;
  desc->raidAddress = raidAddress;
  desc->numBlocks   = numBlocks;
  desc->bufPtr      = bufPtr;
  desc->bp          = bp;
  desc->paramDAG    = paramDAG;
  desc->paramASM    = paramASM;
  desc->flags       = flags;
  desc -> states    = states;
  desc -> state     = 0;

  desc->status      = 0;
  bzero((char *)&desc->tracerec, sizeof(RF_AccTraceEntry_t));
  desc->callbackFunc= (void (*)(RF_CBParam_t))cbF; /* XXX */
  desc->callbackArg = cbA;
  desc->next        = NULL;
  desc->head	    = desc;
  desc->numPending  = 0;
  desc->cleanupList = NULL;
  rf_MakeAllocList(desc->cleanupList);
  rf_get_threadid(desc->tid);
  return(desc);
}

void rf_FreeRaidAccDesc(RF_RaidAccessDesc_t *desc)
{
  RF_Raid_t *raidPtr = desc->raidPtr;

  RF_ASSERT(desc);

  rf_FreeAllocList(desc->cleanupList);
  RF_FREELIST_FREE_CLEAN_NOUNLOCK(rf_rad_freelist,desc,next,clean_rad);
    raidPtr->nAccOutstanding--;
    if (raidPtr->waitShutdown) {
      RF_SIGNAL_COND(raidPtr->outstandingCond);
    }
  RF_FREELIST_DO_UNLOCK(rf_rad_freelist);
}

/*********************************************************************
 * Main routine for performing an access.
 * Accesses are retried until a DAG can not be selected.  This occurs
 * when either the DAG library is incomplete or there are too many
 * failures in a parity group.
 ********************************************************************/
int rf_DoAccess(
  RF_Raid_t                    *raidPtr,
  RF_IoType_t                   type,
  int                           async_flag,
  RF_RaidAddr_t                 raidAddress,
  RF_SectorCount_t              numBlocks,
  caddr_t                       bufPtr,
  void                         *bp_in,
  RF_DagHeader_t              **paramDAG,
  RF_AccessStripeMapHeader_t  **paramASM,
  RF_RaidAccessFlags_t          flags,
  RF_RaidAccessDesc_t         **paramDesc,
  void                        (*cbF)(struct buf *),
  void                         *cbA)
/*
type should be read or write
async_flag should be RF_TRUE or RF_FALSE
bp_in is a buf pointer.  void * to facilitate ignoring it outside the kernel
*/
{
  int tid;
  RF_RaidAccessDesc_t *desc;
  caddr_t lbufPtr = bufPtr;
  struct buf *bp = (struct buf *) bp_in;
#if DFSTRACE > 0
  struct { RF_uint64 raidAddr; int numBlocks; char type;} dfsrecord;
#endif /* DFSTRACE > 0 */

  raidAddress += rf_raidSectorOffset;

  if (!raidPtr->valid) {
    RF_ERRORMSG("RAIDframe driver not successfully configured.  Rejecting access.\n");
    IO_BUF_ERR(bp, EINVAL, raidPtr->raidid);
    return(EINVAL);
  }

#if defined(KERNEL) && DFSTRACE > 0
  if (rf_DFSTraceAccesses) {
    dfsrecord.raidAddr  = raidAddress;
    dfsrecord.numBlocks = numBlocks;
    dfsrecord.type      = type;
    dfs_log(DFS_NOTE, (char *) &dfsrecord, sizeof(dfsrecord), 0);
  }
#endif /* KERNEL && DFSTRACE > 0 */

  rf_get_threadid(tid);
  if (rf_accessDebug) {

	  printf("logBytes is: %d %d %d\n",raidPtr->raidid,
		 raidPtr->logBytesPerSector,
		 (int)rf_RaidAddressToByte(raidPtr,numBlocks));
    printf("[%d] %s raidAddr %d (stripeid %d-%d) numBlocks %d (%d bytes) buf 0x%lx\n",tid,
	   (type==RF_IO_TYPE_READ) ? "READ":"WRITE", (int)raidAddress,
	   (int) rf_RaidAddressToStripeID(&raidPtr->Layout, raidAddress),
	   (int) rf_RaidAddressToStripeID(&raidPtr->Layout, raidAddress+numBlocks-1),
	   (int) numBlocks,
	   (int) rf_RaidAddressToByte(raidPtr,numBlocks),
	   (long) bufPtr);
  }

  if (raidAddress + numBlocks > raidPtr->totalSectors) {

    printf("DoAccess: raid addr %lu too large to access %lu sectors.  Max legal addr is %lu\n",
           (u_long)raidAddress,(u_long)numBlocks,(u_long)raidPtr->totalSectors);

    if (type == RF_IO_TYPE_READ) {
      IO_BUF_ERR(bp, ENOSPC, raidPtr->raidid);
      return(ENOSPC);
    } else {
      IO_BUF_ERR(bp, ENOSPC, raidPtr->raidid);
      return(ENOSPC);
    }
  }

  desc = rf_AllocRaidAccDesc(raidPtr, type, raidAddress,
			  numBlocks, lbufPtr, bp, paramDAG, paramASM,
			  flags, cbF, cbA, raidPtr->Layout.map->states);

  if (desc == NULL) {
    return(ENOMEM);
  }

  RF_ETIMER_START(desc->tracerec.tot_timer);

  desc->async_flag = async_flag;

  rf_ContinueRaidAccess(desc);

  return(0);
}

/* force the array into reconfigured mode without doing reconstruction */
int rf_SetReconfiguredMode(raidPtr, row, col)
  RF_Raid_t  *raidPtr;
  int         row;
  int         col;
{
  if (!(raidPtr->Layout.map->flags & RF_DISTRIBUTE_SPARE)) {
    printf("Can't set reconfigured mode in dedicated-spare array\n");
    RF_PANIC();
  }
  RF_LOCK_MUTEX(raidPtr->mutex);
  raidPtr->numFailures++;
  raidPtr->Disks[row][col].status = rf_ds_dist_spared;
  raidPtr->status[row] = rf_rs_reconfigured;
  /* install spare table only if declustering + distributed sparing architecture. */
  if ( raidPtr->Layout.map->flags & RF_BD_DECLUSTERED )
     rf_InstallSpareTable(raidPtr, row, col);
  RF_UNLOCK_MUTEX(raidPtr->mutex);
  return(0);
}

extern int fail_row, fail_col, fail_time;
extern int delayed_recon;

int rf_FailDisk(
  RF_Raid_t  *raidPtr,
  int         frow,
  int         fcol,
  int         initRecon)
{
  int tid;

  rf_get_threadid(tid);
  printf("[%d] Failing disk r%d c%d\n",tid,frow,fcol);
  RF_LOCK_MUTEX(raidPtr->mutex);
  raidPtr->numFailures++;
  raidPtr->Disks[frow][fcol].status = rf_ds_failed;
  raidPtr->status[frow] = rf_rs_degraded;
  RF_UNLOCK_MUTEX(raidPtr->mutex);
  if (initRecon)
    rf_ReconstructFailedDisk(raidPtr, frow, fcol);
  return(0);
}

/* releases a thread that is waiting for the array to become quiesced.
 * access_suspend_mutex should be locked upon calling this
 */
void rf_SignalQuiescenceLock(raidPtr, reconDesc)
  RF_Raid_t           *raidPtr;
  RF_RaidReconDesc_t  *reconDesc;
{
  int tid;

  if (rf_quiesceDebug) {
    rf_get_threadid(tid);
    printf("[%d] Signalling quiescence lock\n", tid);
  }
  raidPtr->access_suspend_release = 1;

  if (raidPtr->waiting_for_quiescence) {
    SIGNAL_QUIESCENT_COND(raidPtr);
  }
}

/* suspends all new requests to the array.  No effect on accesses that are in flight.  */
int rf_SuspendNewRequestsAndWait(raidPtr)
  RF_Raid_t  *raidPtr;
{
  if (rf_quiesceDebug)
    printf("Suspending new reqs\n");

  RF_LOCK_MUTEX(raidPtr->access_suspend_mutex);
  raidPtr->accesses_suspended++;
  raidPtr->waiting_for_quiescence = (raidPtr->accs_in_flight == 0) ? 0 : 1;

  if (raidPtr->waiting_for_quiescence) {
    raidPtr->access_suspend_release=0;
    while (!raidPtr->access_suspend_release) {
	    printf("Suspending: Waiting for Quiesence\n");
      WAIT_FOR_QUIESCENCE(raidPtr);
      raidPtr->waiting_for_quiescence = 0;
    }
  }
  printf("Quiesence reached..\n");

  RF_UNLOCK_MUTEX(raidPtr->access_suspend_mutex);
  return (raidPtr->waiting_for_quiescence);
}

/* wake up everyone waiting for quiescence to be released */
void rf_ResumeNewRequests(raidPtr)
  RF_Raid_t  *raidPtr;
{
  RF_CallbackDesc_t *t, *cb;

  if (rf_quiesceDebug)
    printf("Resuming new reqs\n");

  RF_LOCK_MUTEX(raidPtr->access_suspend_mutex);
  raidPtr->accesses_suspended--;
  if (raidPtr->accesses_suspended == 0)
    cb = raidPtr->quiesce_wait_list;
  else
    cb = NULL;
  raidPtr->quiesce_wait_list = NULL;
  RF_UNLOCK_MUTEX(raidPtr->access_suspend_mutex);

  while (cb) {
    t = cb;
    cb = cb->next;
    (t->callbackFunc)(t->callbackArg);
    rf_FreeCallbackDesc(t);
  }
}

/*****************************************************************************************
 *
 * debug routines
 *
 ****************************************************************************************/

static void set_debug_option(name, val)
  char  *name;
  long   val;
{
  RF_DebugName_t *p;

  for (p = rf_debugNames; p->name; p++) {
    if (!strcmp(p->name, name)) {
      *(p->ptr) = val;
      printf("[Set debug variable %s to %ld]\n",name,val);
      return;
    }
  }
  RF_ERRORMSG1("Unknown debug string \"%s\"\n",name);
}


/* would like to use sscanf here, but apparently not available in kernel */
/*ARGSUSED*/
static void rf_ConfigureDebug(cfgPtr)
  RF_Config_t  *cfgPtr;
{
  char *val_p, *name_p, *white_p;
  long val;
  int i;

  rf_ResetDebugOptions();
  for (i=0; cfgPtr->debugVars[i][0] && i < RF_MAXDBGV; i++) {
    name_p  = rf_find_non_white(&cfgPtr->debugVars[i][0]);
    white_p = rf_find_white(name_p);                                   /* skip to start of 2nd word */
    val_p   = rf_find_non_white(white_p);
    if (*val_p == '0' && *(val_p+1) == 'x') val = rf_htoi(val_p+2);
    else val = rf_atoi(val_p);
    *white_p = '\0';
    set_debug_option(name_p, val);
  }
}

/* performance monitoring stuff */

#define TIMEVAL_TO_US(t) (((long) t.tv_sec) * 1000000L + (long) t.tv_usec)

#if !defined(_KERNEL) && !defined(SIMULATE)

/*
 * Throughput stats currently only used in user-level RAIDframe
 */

static int rf_InitThroughputStats(
  RF_ShutdownList_t  **listp,
  RF_Raid_t           *raidPtr,
  RF_Config_t         *cfgPtr)
{
  int rc;

  /* these used by user-level raidframe only */
  rc = rf_create_managed_mutex(listp, &raidPtr->throughputstats.mutex);
  if (rc) {
    RF_ERRORMSG3("Unable to init mutex file %s line %d rc=%d\n", __FILE__,
      __LINE__, rc);
    return(rc);
  }
  raidPtr->throughputstats.sum_io_us = 0;
  raidPtr->throughputstats.num_ios = 0;
  raidPtr->throughputstats.num_out_ios = 0;
  return(0);
}

void rf_StartThroughputStats(RF_Raid_t *raidPtr)
{
  RF_LOCK_MUTEX(raidPtr->throughputstats.mutex);
  raidPtr->throughputstats.num_ios++;
  raidPtr->throughputstats.num_out_ios++;
  if (raidPtr->throughputstats.num_out_ios == 1)
    RF_GETTIME(raidPtr->throughputstats.start);
  RF_UNLOCK_MUTEX(raidPtr->throughputstats.mutex);
}

static void rf_StopThroughputStats(RF_Raid_t *raidPtr)
{
  struct timeval diff;

  RF_LOCK_MUTEX(raidPtr->throughputstats.mutex);
  raidPtr->throughputstats.num_out_ios--;
  if (raidPtr->throughputstats.num_out_ios == 0) {
    RF_GETTIME(raidPtr->throughputstats.stop);
    RF_TIMEVAL_DIFF(&raidPtr->throughputstats.start, &raidPtr->throughputstats.stop, &diff);
    raidPtr->throughputstats.sum_io_us += TIMEVAL_TO_US(diff);
  }
  RF_UNLOCK_MUTEX(raidPtr->throughputstats.mutex);
}

static void rf_PrintThroughputStats(RF_Raid_t *raidPtr)
{
  RF_ASSERT(raidPtr->throughputstats.num_out_ios == 0);
  if ( raidPtr->throughputstats.sum_io_us != 0 ) {
     printf("[Througphut: %8.2f IOs/second]\n", raidPtr->throughputstats.num_ios
       / (raidPtr->throughputstats.sum_io_us / 1000000.0));
  }
}

#endif /* !KERNEL && !SIMULATE */

void rf_StartUserStats(RF_Raid_t *raidPtr)
{
  RF_GETTIME(raidPtr->userstats.start);
  raidPtr->userstats.sum_io_us = 0;
  raidPtr->userstats.num_ios = 0;
  raidPtr->userstats.num_sect_moved = 0;
}

void rf_StopUserStats(RF_Raid_t *raidPtr)
{
  RF_GETTIME(raidPtr->userstats.stop);
}

void rf_UpdateUserStats(raidPtr, rt, numsect)
  RF_Raid_t  *raidPtr;
  int         rt;       /* resp time in us */
  int         numsect;  /* number of sectors for this access */
{
  raidPtr->userstats.sum_io_us += rt;
  raidPtr->userstats.num_ios++;
  raidPtr->userstats.num_sect_moved += numsect;
}

void rf_PrintUserStats(RF_Raid_t *raidPtr)
{
  long elapsed_us, mbs, mbs_frac;
  struct timeval diff;

  RF_TIMEVAL_DIFF(&raidPtr->userstats.start, &raidPtr->userstats.stop, &diff);
  elapsed_us = TIMEVAL_TO_US(diff);

  /* 2000 sectors per megabyte, 10000000 microseconds per second */
  if (elapsed_us)
    mbs = (raidPtr->userstats.num_sect_moved / 2000) / (elapsed_us / 1000000);
  else
    mbs = 0;

  /* this computes only the first digit of the fractional mb/s moved */
  if (elapsed_us) {
    mbs_frac = ((raidPtr->userstats.num_sect_moved / 200) / (elapsed_us / 1000000))
      - (mbs * 10);
  }
  else {
    mbs_frac = 0;
  }

  printf("Number of I/Os:             %ld\n",raidPtr->userstats.num_ios);
  printf("Elapsed time (us):          %ld\n",elapsed_us);
  printf("User I/Os per second:       %ld\n",RF_DB0_CHECK(raidPtr->userstats.num_ios, (elapsed_us/1000000)));
  printf("Average user response time: %ld us\n",RF_DB0_CHECK(raidPtr->userstats.sum_io_us, raidPtr->userstats.num_ios));
  printf("Total sectors moved:        %ld\n",raidPtr->userstats.num_sect_moved);
  printf("Average access size (sect): %ld\n",RF_DB0_CHECK(raidPtr->userstats.num_sect_moved, raidPtr->userstats.num_ios));
  printf("Achieved data rate:         %ld.%ld MB/sec\n",mbs,mbs_frac);
}