/*      $NetBSD: rf_configure.c,v 1.8 1999/08/13 03:37:42 oster 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_); \
  }

char   *rf_find_non_white(char *p);
char   *rf_find_white(char *p);



static int rf_search_file_for_start_of(char *string, char *buf, int len,
	FILE *fp);
static int rf_get_next_nonblank_line(char *buf, int len, FILE *fp,
	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 *c;
    bcopy(buf1, cfgPtr->diskQueueType, RF_MIN(sizeof(cfgPtr->diskQueueType), strlen(buf1)+1));
    for(c=buf1;*c;c++) {
      if (*c == ' ') {
        *c = '\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;
  }

  /* XXX who cares.. it's not going into the kernel, so we should ignore this... */
#ifndef KERNEL
  retcode = lp->MakeLayoutSpecific(fp, cfgPtr, lp->makeLayoutSpecificArg);
#endif
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);
  }

  fgets(buf,256,fp);
  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)
  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;
  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_ERRORMSG(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);
}