/*	$OpenBSD: rf_configure.c,v 1.5 2001/12/29 21:54:57 tdeval Exp $	*/
/*	$NetBSD: rf_configure.c,v 1.14 2001/02/04 21:05:42 christos Exp $	*/

/*
 * Copyright (c) 1995 Carnegie-Mellon University.
 * All rights reserved.
 *
 * Author: Mark Holland
 *
 * 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@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_configure.c -- code related to configuring the raidframe system
 *
 * configuration is complicated by the fact that we want the same
 * driver to work both in the kernel and at user level.  In the
 * kernel, we can't read the configuration file, so we configure
 * by running a user-level program that reads the config file,
 * creates a data structure describing the configuration and
 * passes it into the kernel via an ioctl.  Since we want the config
 * code to be common between the two versions of the driver, we
 * configure using the same two-step process when running at
 * user level.  Of course, at user level, the config structure is
 * passed directly to the config routine, rather than via ioctl.
 *
 * This file is not compiled into the kernel, so we have no
 * need for KERNEL ifdefs.
 *
 **************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <strings.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "rf_raid.h"
#include "rf_raidframe.h"
#include "rf_general.h"
#include "rf_decluster.h"
#include "rf_configure.h"

/* 
 * XXX we include this here so we don't need to drag rf_debugMem.c into
 * the picture...  This is userland, afterall...
 */

/*
 * XXX sucky hack to override the defn. of RF_Malloc as given in
 * rf_debugMem.c...  but I *really* don't want (nor need) to link with
 * that file here in userland..  GO
*/

#undef RF_Malloc
#define RF_Malloc(_p_, _size_, _cast_) \
  { \
     _p_ = _cast_ malloc((u_long)_size_); \
     bzero((char *)_p_, _size_); \
  }

int     distSpareYes = 1;
int     distSpareNo = 0;

/* The mapsw[] table below contains all the various RAID types that might
   be supported by the kernel.  The actual supported types are found
   in sys/dev/raidframe/rf_layout.c. */

static RF_LayoutSW_t mapsw[] = {
	/* parity declustering */
	{'T', "Parity declustering",
	 rf_MakeLayoutSpecificDeclustered, &distSpareNo},
	/* parity declustering with distributed sparing */
	{'D', "Distributed sparing parity declustering",
	 rf_MakeLayoutSpecificDeclustered, &distSpareYes},
	/* declustered P+Q */
	{'Q', "Declustered P+Q",
	 rf_MakeLayoutSpecificDeclustered, &distSpareNo},
	/* RAID 5 with rotated sparing */
	{'R', "RAID Level 5 rotated sparing", rf_MakeLayoutSpecificNULL, NULL},
	/* Chained Declustering */
	{'C', "Chained Declustering", rf_MakeLayoutSpecificNULL, NULL},
	/* Interleaved Declustering */
	{'I', "Interleaved Declustering", rf_MakeLayoutSpecificNULL, NULL},
	/* RAID level 0 */
	{'0', "RAID Level 0", rf_MakeLayoutSpecificNULL, NULL},
	/* RAID level 1 */
	{'1', "RAID Level 1", rf_MakeLayoutSpecificNULL, NULL},
	/* RAID level 4 */
	{'4', "RAID Level 4", rf_MakeLayoutSpecificNULL, NULL},
	/* RAID level 5 */
	{'5', "RAID Level 5", rf_MakeLayoutSpecificNULL, NULL},
	/* Evenodd */
	{'E', "EvenOdd", rf_MakeLayoutSpecificNULL, NULL},
	/* Declustered Evenodd */
	{'e', "Declustered EvenOdd",
	 rf_MakeLayoutSpecificDeclustered, &distSpareNo},
	/* parity logging */
	{'L', "Parity logging", rf_MakeLayoutSpecificNULL, NULL},
	/* end-of-list marker */
	{'\0', NULL, NULL, NULL}
};
RF_LayoutSW_t *
rf_GetLayout(RF_ParityConfig_t parityConfig)
{
	RF_LayoutSW_t *p;

	/* look up the specific layout */
	for (p = &mapsw[0]; p->parityConfig; p++)
		if (p->parityConfig == parityConfig)
			break;
	if (!p->parityConfig)
		return (NULL);
	RF_ASSERT(p->parityConfig == parityConfig);
	return (p);
}

static int rf_search_file_for_start_of(const char *string, char *buf,
    int len, FILE * fp);
static int rf_get_next_nonblank_line(char *buf, int len, FILE *fp,
    const char *errmsg);

/*
 * called from user level to read the configuration file and create
 * a configuration control structure.  This is used in the user-level
 * version of the driver, and in the user-level program that configures
 * the system via ioctl.
 */
int 
rf_MakeConfig(configname, cfgPtr)
  char         *configname;
  RF_Config_t  *cfgPtr;
{
  int numscanned, val, r, c, retcode, aa, bb, cc;
  char buf[256], buf1[256], *cp;
  RF_LayoutSW_t *lp;
  FILE *fp;

  bzero((char *)cfgPtr, sizeof(RF_Config_t));

  fp = fopen(configname, "r");
  if (!fp) {
    RF_ERRORMSG1("Can't open config file %s\n",configname);
    return(-1);
  }
  rewind(fp);
  if (rf_search_file_for_start_of("array", buf, 256, fp)) {
    RF_ERRORMSG1("Unable to find start of \"array\" params in config file %s\n",configname);
		retcode = -1;
		goto out;
  }
  rf_get_next_nonblank_line(buf, 256, fp, "Config file error (\"array\" section):  unable to get numRow and numCol\n");

  /*
         * wackiness with aa, bb, cc to get around size problems on
         * different platforms
   */
  numscanned = sscanf(buf,"%d %d %d", &aa, &bb, &cc);
  if (numscanned != 3) {
    RF_ERRORMSG("Config file error (\"array\" section):  unable to get numRow, numCol, numSpare\n");
		retcode = -1;
		goto out;
  }
  cfgPtr->numRow = (RF_RowCol_t)aa;
  cfgPtr->numCol = (RF_RowCol_t)bb;
  cfgPtr->numSpare = (RF_RowCol_t)cc;

  /* debug section is optional */
  for (c=0; c<RF_MAXDBGV; c++)
    cfgPtr->debugVars[c][0] = '\0';
  rewind(fp);
  if (!rf_search_file_for_start_of("debug", buf, 256, fp)) {
    for (c=0; c < RF_MAXDBGV; c++) {
			if (rf_get_next_nonblank_line(buf, 256, fp, NULL))
				break;
      cp = rf_find_non_white(buf);
			if (!strncmp(cp, "START", strlen("START")))
				break;
      (void) strcpy(&cfgPtr->debugVars[c][0], cp);
    }
  }
  rewind(fp);
  strcpy(cfgPtr->diskQueueType,"fifo");
  cfgPtr->maxOutstandingDiskReqs = 1;
  /* scan the file for the block related to disk queues */
  if (rf_search_file_for_start_of("queue",buf,256,fp)) {
    RF_ERRORMSG2("[No disk queue discipline specified in config file %s.  Using %s.]\n",configname, cfgPtr->diskQueueType);
  } else {
    if (rf_get_next_nonblank_line(buf, 256, fp, NULL)) {
      RF_ERRORMSG2("[No disk queue discipline specified in config file %s.  Using %s.]\n",configname, cfgPtr->diskQueueType);
    }
  }

	/* the queue specifier line contains two entries: 1st char of first
	 * word specifies queue to be used 2nd word specifies max num reqs
	 * that can be outstanding on the disk itself (typically 1) */
  if (sscanf(buf,"%s %d",buf1,&val)!=2) {
    RF_ERRORMSG1("Can't determine queue type and/or max outstanding reqs from line: %s",buf);
    RF_ERRORMSG2("Using %s-%d\n", cfgPtr->diskQueueType, cfgPtr->maxOutstandingDiskReqs);
  } else {
		char *ch;
		bcopy(buf1, cfgPtr->diskQueueType,
		    RF_MIN(sizeof(cfgPtr->diskQueueType), strlen(buf1) + 1));
		for (ch = buf1; *ch; ch++) {
			if (*ch == ' ') {
				*ch = '\0';
        break;
      }
    }
    cfgPtr->maxOutstandingDiskReqs = val;
  }

  rewind(fp);

  if (rf_search_file_for_start_of("disks",buf,256,fp)) {
    RF_ERRORMSG1("Can't find \"disks\" section in config file %s\n",configname);
		retcode = -1;
		goto out;
  }
  for (r=0; r<cfgPtr->numRow; r++) {
    for (c=0; c<cfgPtr->numCol; c++) {
			if (rf_get_next_nonblank_line(
			    &cfgPtr->devnames[r][c][0], 50, fp, NULL)) {
	RF_ERRORMSG2("Config file error: unable to get device file for disk at row %d col %d\n",r,c);
				retcode = -1;
				goto out;
      }
    }
  }

  /* "spare" section is optional */
  rewind(fp);
	if (rf_search_file_for_start_of("spare", buf, 256, fp))
		cfgPtr->numSpare = 0;
  for (c = 0; c < cfgPtr->numSpare; c++) {
		if (rf_get_next_nonblank_line(&cfgPtr->spare_names[c][0],
		    256, fp, NULL)) {
      RF_ERRORMSG1("Config file error: unable to get device file for spare disk %d\n",c);
			retcode = -1;
			goto out;
    }
  }

  /* scan the file for the block related to layout */
  rewind(fp);
  if (rf_search_file_for_start_of("layout",buf,256,fp)) {
    RF_ERRORMSG1("Can't find \"layout\" section in configuration file %s\n",configname);
		retcode = -1;
		goto out;
  }
  if (rf_get_next_nonblank_line(buf, 256, fp, NULL)) {
    RF_ERRORMSG("Config file error (\"layout\" section): unable to find common layout param line\n");
		retcode = -1;
		goto out;
  }
  c = sscanf(buf,"%d %d %d %c", &aa, &bb, &cc, &cfgPtr->parityConfig);
  cfgPtr->sectPerSU = (RF_SectorNum_t)aa;
  cfgPtr->SUsPerPU = (RF_StripeNum_t)bb;
  cfgPtr->SUsPerRU = (RF_StripeNum_t)cc;
  if (c != 4) {
    RF_ERRORMSG("Unable to scan common layout line\n");
		retcode = -1;
		goto out;
  }
  lp = rf_GetLayout(cfgPtr->parityConfig);
  if (lp == NULL) {
		RF_ERRORMSG1("Unknown parity config '%c'\n",
		    cfgPtr->parityConfig);
    retcode = -1;
    goto out;
  }

  retcode = lp->MakeLayoutSpecific(fp, cfgPtr, lp->makeLayoutSpecificArg);
out:
  fclose(fp);
  if (retcode < 0)
    retcode = errno = EINVAL;
  else
    errno = retcode;
  return(retcode);
}


/* used in architectures such as RAID0 where there is no layout-specific
 * information to be passed into the configuration code.
 */
int 
rf_MakeLayoutSpecificNULL(fp, cfgPtr, ignored)
  FILE         *fp;
  RF_Config_t  *cfgPtr;
  void         *ignored;
{
  cfgPtr->layoutSpecificSize = 0;
  cfgPtr->layoutSpecific     = NULL;
  return(0);
}

int 
rf_MakeLayoutSpecificDeclustered(configfp, cfgPtr, arg)
  FILE         *configfp;
  RF_Config_t  *cfgPtr;
  void         *arg;
{
  int b, v, k, r, lambda, norotate, i, val, distSpare;
  char *cfgBuf, *bdfile, *p, *smname;
  char buf[256], smbuf[256];
  FILE *fp;

  distSpare = *((int *)arg);

  /* get the block design file name */
	if (rf_get_next_nonblank_line(buf, 256, configfp,
	    "Can't find block design file name in config file\n"))
    return(EINVAL);
  bdfile = rf_find_non_white(buf);
  if (bdfile[strlen(bdfile)-1] == '\n') {
    /* strip newline char */
    bdfile[strlen(bdfile)-1] = '\0';
  }
  /* open bd file, check validity of configuration */
  if ((fp = fopen(bdfile,"r"))==NULL) {
    RF_ERRORMSG1("RAID: config error: Can't open layout table file %s\n",bdfile);
    return(EINVAL);
  }
	if (fgets(buf, 256, fp) == NULL) {
		RF_ERRORMSG1("RAID: config error: Can't read layout from layout table file %s\n", bdfile);
		return (EINVAL);
	}
  i = sscanf(buf,"%u %u %u %u %u %u",&b,&v,&k,&r,&lambda,&norotate);
  if (i == 5)
    norotate = 0; /* no-rotate flag is optional */
  else if (i != 6) {
    RF_ERRORMSG("Unable to parse header line in block design file\n");
    return(EINVAL);
  }
	/* set the sparemap directory.  In the in-kernel version, there's a
	 * daemon that's responsible for finding the sparemaps */
  if (distSpare) {
		if (rf_get_next_nonblank_line(smbuf, 256, configfp,
		    "Can't find sparemap file name in config file\n"))
      return(EINVAL);
    smname = rf_find_non_white(smbuf);
    if (smname[strlen(smname)-1] == '\n') {
      /* strip newline char */
      smname[strlen(smname)-1] = '\0';
    }
	} else {
    smbuf[0] = '\0';
    smname = smbuf;
  }

  /* allocate a buffer to hold the configuration info */
	cfgPtr->layoutSpecificSize = RF_SPAREMAP_NAME_LEN +
	    6 * sizeof(int) + b * k;
  /* can't use RF_Malloc here b/c debugMem module not yet init'd */
  cfgBuf = (char *) malloc(cfgPtr->layoutSpecificSize);          
  cfgPtr->layoutSpecific = (void *) cfgBuf;
  p = cfgBuf;

  /* install name of sparemap file */
  for (i=0; smname[i]; i++)
    *p++ = smname[i];
  /* pad with zeros */
  while (i<RF_SPAREMAP_NAME_LEN) {
    *p++ = '\0';
    i++;
  }

  /*
   * fill in the buffer with the block design parameters
   * and then the block design itself
   */
	*((int *) p) = b;
	p += sizeof(int);
	*((int *) p) = v;
	p += sizeof(int);
	*((int *) p) = k;
	p += sizeof(int);
	*((int *) p) = r;
	p += sizeof(int);
	*((int *) p) = lambda;
	p += sizeof(int);
	*((int *) p) = norotate;
	p += sizeof(int);

  while (fscanf(fp,"%d",&val) == 1)
    *p++ = (char) val;
  fclose(fp);
  if (p - cfgBuf != cfgPtr->layoutSpecificSize) {
      RF_ERRORMSG2("Size mismatch creating layout specific data: is %d sb %d bytes\n",(int)(p-cfgBuf),(int)(6*sizeof(int)+b*k));
      return(EINVAL);
  }
  return(0);
}

/****************************************************************************
 *
 * utilities
 *
 ***************************************************************************/
 
/* finds a non-white character in the line */
char   *
rf_find_non_white(char *p)
{
	for (; *p != '\0' && (*p == ' ' || *p == '\t'); p++);
	return (p);
}

/* finds a white character in the line */
char   *
rf_find_white(char *p)
{
	for (; *p != '\0' && (*p != ' ' && *p != '\t'); p++);
	return (p);
}

/*
 * searches a file for a line that says "START string", where string is
 * specified as a parameter
 */
static int 
rf_search_file_for_start_of(string, buf, len, fp)
	const char *string;
  char  *buf;
  int    len;
  FILE  *fp;
{
  char *p;

  while (1) {
		if (fgets(buf, len, fp) == NULL)
			return (-1);
    p = rf_find_non_white(buf);
    if (!strncmp(p, "START", strlen("START"))) {
      p = rf_find_white(p);
      p = rf_find_non_white(p);
			if (!strncmp(p, string, strlen(string)))
				return (0);
    }
  }
}

/* reads from file fp into buf until it finds an interesting line */
int 
rf_get_next_nonblank_line(buf, len, fp, errmsg)
  char  *buf;
  int    len;
  FILE  *fp;
	const char *errmsg;
{
  char *p;

  while (fgets(buf,256,fp) != NULL) {
    p = rf_find_non_white(buf);
		if (*p == '\n' || *p == '\0' || *p == '#')
			continue;
    return(0);
  }
	if (errmsg)
		RF_ERRORMSG1("%s", errmsg);
  return(1);
}

/*
 * Allocates an array for the spare table, and initializes it from a file.
 * In the user-level version, this is called when recon is initiated.
 * When/if I move recon into the kernel, there'll be a daemon that does
 * an ioctl into raidframe which will block until a spare table is needed.
 * When it returns, it will read a spare table from the file system,
 * pass it into the kernel via a different ioctl, and then block again
 * on the original ioctl.
 *
 * This is specific to the declustered layout, but doesn't belong in
 * rf_decluster.c because it uses stuff that can't be compiled into
 * the kernel, and it needs to be compiled into the user-level sparemap daemon.
 *
 */
void *
rf_ReadSpareTable(req, fname)
  RF_SparetWait_t  *req;
  char             *fname;
{
	int i, j, numFound, linecount, tableNum, tupleNum,
	    spareDisk, spareBlkOffset;
  char buf[1024], targString[100], errString[100];
  RF_SpareTableEntry_t **table;
  FILE *fp;

  /* allocate and initialize the table */
	RF_Malloc(table,
	    req->TablesPerSpareRegion * sizeof(RF_SpareTableEntry_t *),
	    (RF_SpareTableEntry_t **));
  for (i=0; i<req->TablesPerSpareRegion; i++) {
		RF_Malloc(table[i],
		    req->BlocksPerTable * sizeof(RF_SpareTableEntry_t),
		    (RF_SpareTableEntry_t *));
		for (j = 0; j < req->BlocksPerTable; j++)
			table[i][j].spareDisk =
			    table[i][j].spareBlockOffsetInSUs = -1;
  }

  /* 2.  open sparemap file, sanity check */
  if ((fp = fopen(fname,"r"))==NULL) {
		fprintf(stderr,
		    "rf_ReadSpareTable:  Can't open sparemap file %s\n", fname);
		return (NULL);
  }
	if (rf_get_next_nonblank_line(buf, 1024, fp,
	    "Invalid sparemap file:  can't find header line\n"))
    return(NULL);
  if (buf[strlen(buf)-1] == '\n')
    buf[strlen(buf)-1] = '\0';

  sprintf(targString, "fdisk %d\n", req->fcol);
	sprintf(errString,
	    "Invalid sparemap file:  can't find \"fdisk %d\" line\n",
	    req->fcol);
  while (1) {
    rf_get_next_nonblank_line(buf,1024,fp,errString);
		if (!strncmp(buf, targString, strlen(targString)))
			break;
  }

  /* no more blank lines or comments allowed now */
  linecount = req->TablesPerSpareRegion * req->TableDepthInPUs;
  for (i=0; i<linecount; i++) {
		numFound = fscanf(fp, " %d %d %d %d", &tableNum, &tupleNum,
		    &spareDisk, &spareBlkOffset);
    if (numFound != 4) {
			fprintf(stderr, "Sparemap file prematurely exhausted after %d of %d lines\n", i, linecount);
			return (NULL);
    }
		RF_ASSERT(tableNum >= 0 &&
		    tableNum < req->TablesPerSpareRegion);
    RF_ASSERT(tupleNum >= 0 && tupleNum < req->BlocksPerTable);
    RF_ASSERT(spareDisk >= 0 && spareDisk < req->C);
		RF_ASSERT(spareBlkOffset >= 0 && spareBlkOffset <
		    req->SpareSpaceDepthPerRegionInSUs / req->SUsPerPU);

    table[tableNum][tupleNum].spareDisk = spareDisk;
		table[tableNum][tupleNum].spareBlockOffsetInSUs =
		    spareBlkOffset * req->SUsPerPU;
  }

  fclose(fp);
  return((void *) table);
}