rf_camlayer.c

RAIDFrame是个非常好的磁盘阵列RAID仿真工具

/*
 * 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  [e-mail]
 *  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.
 */

/********************************************************************************
 * camlayer.c -- code for interfacing to the OSF/1 CAM layer
 *
 * the generic call structure is to allocate a RF_DiskOp_t data structure describing
 * what you want to do by calling one of the "alloc" routines, then actually
 * do the op by calling the corresponding "do" routine, and the free the RF_DiskOp_t
 * by calling FreeDiskOp.
 *******************************************************************************/

/* $Locker:  $
 * $Log: rf_camlayer.c,v $
 * Revision 1.33  1996/08/16  17:51:22  jimz
 * begin AIX additions
 *
 * Revision 1.32  1996/07/19  16:10:34  jimz
 * deal better with disk labels + partitions
 *
 * Revision 1.31  1996/07/18  22:57:14  jimz
 * port simulator to AIX
 *
 * Revision 1.30  1996/07/15  17:22:18  jimz
 * nit-pick code cleanup
 * resolve stdlib problems on DEC OSF
 *
 * Revision 1.29  1996/06/10  11:55:47  jimz
 * Straightened out some per-array/not-per-array distinctions, fixed
 * a couple bugs related to confusion. Added shutdown lists. Removed
 * layout shutdown function (now subsumed by shutdown lists).
 *
 * Revision 1.28  1996/06/09  02:36:46  jimz
 * lots of little crufty cleanup- fixup whitespace
 * issues, comment #ifdefs, improve typing in some
 * places (esp size-related)
 *
 * Revision 1.27  1996/06/07  21:33:04  jimz
 * begin using consistent types for sector numbers,
 * stripe numbers, row+col numbers, recon unit numbers
 *
 * Revision 1.26  1996/06/05  18:06:02  jimz
 * Major code cleanup. The Great Renaming is now done.
 * Better modularity. Better typing. Fixed a bunch of
 * synchronization bugs. Made a lot of global stuff
 * per-desc or per-array. Removed dead code.
 *
 * Revision 1.25  1996/06/03  23:28:26  jimz
 * more bugfixes
 * check in tree to sync for IPDS runs with current bugfixes
 * there still may be a problem with threads in the script test
 * getting I/Os stuck- not trivially reproducible (runs ~50 times
 * in a row without getting stuck)
 *
 * Revision 1.24  1996/05/30  23:22:16  jimz
 * bugfixes of serialization, timing problems
 * more cleanup
 *
 * Revision 1.23  1996/05/30  11:29:41  jimz
 * Numerous bug fixes. Stripe lock release code disagreed with the taking code
 * about when stripes should be locked (I made it consistent: no parity, no lock)
 * There was a lot of extra serialization of I/Os which I've removed- a lot of
 * it was to calculate values for the cache code, which is no longer with us.
 * More types, function, macro cleanup. Added code to properly quiesce the array
 * on shutdown. Made a lot of stuff array-specific which was (bogusly) general
 * before. Fixed memory allocation, freeing bugs.
 *
 * Revision 1.22  1996/05/27  18:56:37  jimz
 * more code cleanup
 * better typing
 * compiles in all 3 environments
 *
 * Revision 1.21  1996/05/24  22:17:04  jimz
 * continue code + namespace cleanup
 * typed a bunch of flags
 *
 * Revision 1.20  1996/05/23  21:46:35  jimz
 * checkpoint in code cleanup (release prep)
 * lots of types, function names have been fixed
 *
 * Revision 1.19  1996/05/23  00:33:23  jimz
 * code cleanup: move all debug decls to rf_options.c, all extern
 * debug decls to rf_options.h, all debug vars preceded by rf_
 *
 * Revision 1.18  1996/05/18  19:51:34  jimz
 * major code cleanup- fix syntax, make some types consistent,
 * add prototypes, clean out dead code, et cetera
 *
 * Revision 1.17  1996/05/06  18:44:23  jimz
 * add ShutdownCamLayer()
 *
 * Revision 1.16  1995/12/12  18:10:06  jimz
 * MIN -> RF_MIN, MAX -> RF_MAX, ASSERT -> RF_ASSERT
 * fix 80-column brain damage in comments
 *
 * Revision 1.15  1995/12/01  15:16:19  root
 * added copyright info
 *
 */

#ifdef __osf__

#ifndef KERNEL
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <strings.h>
#include <ctype.h>
#include <unistd.h>
#include <sys/ioctl.h>
#else /* !KERNEL */
#include <labels.h>
#endif /* !KERNEL */

#include "rf_types.h"
#include "rf_sys.h"
#include "rf_ccmn.h"
#include "rf_raid.h"
#include "rf_general.h"
#include "rf_camlayer.h"
#include "rf_shutdown.h"
#include "rf_options.h"

/* A "handle" data structure via which we can do I/O through the cam layer
 * The ua_ccb is not used in the kernel.  Will it mess up anything to leave it here anyway?
 * We could hack around it by #ifdef'ing it out when in the kernel, but it doesn't seem worth it.
 */
typedef struct _cam_io_handle {
  UAGT_CAM_CCB   ua_ccb;
  CCB_SCSIIO     ccb;
  unsigned char  snsBuf[RF_CAM_SENSEDATALEN];
} CamIOHandle;

static int camfd = (-1);            /* file descriptor for /dev/cam */
#ifndef KERNEL
static void rf_release_sim_queue(CCB_SCSIIO *ccb);
static void rf_print_ccb_status(CCB_HEADER  *cp);
#endif /* !KERNEL */

#ifndef KERNEL
/*ARGSUSED*/
static void rf_ShutdownCamLayer(ignored)
  void  *ignored;
{
	int rc;

	rc = close(camfd);
	camfd = (-1);
}
#endif /* !KERNEL */

/*ARGSUSED*/
int rf_ConfigureCamLayer(listp)
  RF_ShutdownList_t  **listp;
{
#ifndef KERNEL
  int rc;

  /* open the cam file */
  if ((camfd = open("/dev/cam", O_RDWR, 0)) < 0) {
    RF_ERRORMSG("Unable to open /dev/cam\n");
    perror("CAM open");
    return(errno);
  }
  rc = rf_ShutdownCreate(listp, rf_ShutdownCamLayer, NULL);
  if (rc) {
    RF_ERRORMSG3("Unable to add to shutdown list file %s line %d rc=%d\n",
      __FILE__, __LINE__, rc);
    close(camfd);
    return(rc);
  }
#endif /* !KERNEL */

  return(0);
}

/********************************************************************************
 *
 * creates/destroys a "handle" via which we can do I/O through the cam layer
 * the return value is cast to void * so that the caller need not know
 * anything at all about cam data structures.
 *
 *******************************************************************************/
void *rf_CreateCamIOHandle()
{
  CamIOHandle *p;

  RF_Malloc(p, sizeof(CamIOHandle), (CamIOHandle *));
  return((void *)p);
}

void rf_DestroyCamIOHandle(h)
  void  *h;
{
  RF_Free((CamIOHandle *)h,sizeof(CamIOHandle)); /* unspeakably gratuitous castage here */
}

/********************************************************************************
 * extracts the bus & target IDs from the device file name.
 * assumes that the file name conforms to the DEC OSF/1 spec
 *******************************************************************************/
int rf_extract_ids(name, bus_id, targ_id, lun)
  char  *name;
  int   *bus_id;
  int   *targ_id;
  int   *lun;
{
  char *p;
  unsigned devnum;

  for (p=name; (*p) && (*p<'0' || *p>'9'); p++);
  if (!*p) {
    printf("Invalid device name for disk device \"%s\".\n",name);
    return(ENODEV);
  }
  if (p > name && (*(p-1) >= 'a' && *(p-1) <= 'g')) *lun = *(p-1) - 'a' + 1;
  else *lun = 0;
  devnum = atoi(p);
  *targ_id = devnum&0x7;
  *bus_id  = devnum>>3;
  return(0);
}


/********************************************************************************
 * these are utility routines used by the code below.
 *******************************************************************************/

#ifndef KERNEL
/* allocate the data structures */
#define RF_ALLOCATE_CCB_AND_SENSE(_uaccb_, _ccb_, _sns_) { \
  RF_Calloc(_ccb_, 1, sizeof(CCB_SCSIIO), (CCB_SCSIIO *)); \
  RF_Calloc(_uaccb_, 1, sizeof(UAGT_CAM_CCB), (UAGT_CAM_CCB *)); \
  RF_Calloc(_sns_, 1, sizeof(ALL_REQ_SNS_DATA), (ALL_REQ_SNS_DATA *)); \
}
  
/* set up some default parameters */
static void rf_set_default_ccb_params(
  UAGT_CAM_CCB      *ua_ccb,
  CCB_SCSIIO        *ccb,
  ALL_REQ_SNS_DATA  *sns,
  unsigned           direction,
  u_char            *dataptr,
  unsigned           datalen,
  unsigned           cdblen)
{
  ccb->cam_ch.my_addr        = (struct ccb_header *) ccb;
  ccb->cam_ch.cam_ccb_len    = sizeof(CCB_SCSIIO);
  ccb->cam_ch.cam_func_code  = XPT_SCSI_IO;
  ccb->cam_sense_ptr         = (u_char *) sns;
  ccb->cam_sense_len         = (u_char)sizeof(*sns);
  ccb->cam_ch.cam_flags      = direction;
  ccb->cam_data_ptr          = (u_char *) dataptr;
  ccb->cam_dxfer_len         = datalen;
  ccb->cam_cdb_len           = cdblen;
  ccb->cam_timeout           = CAM_TIME_DEFAULT;
  
  ua_ccb->uagt_ccb           = (CCB_HEADER *) ccb;
  ua_ccb->uagt_ccblen        = sizeof(CCB_SCSIIO);
  ua_ccb->uagt_snsbuf        = (u_char *) sns;
  ua_ccb->uagt_snslen        = sizeof(*sns);
  ua_ccb->uagt_cdb           = (CDB_UN *) NULL;
  ua_ccb->uagt_cdblen        = 0;
  ua_ccb->uagt_buffer        = dataptr;
  ua_ccb->uagt_buflen        = datalen;
}
#endif /* !KERNEL */

/********************************************************************************
 * the next few routines allocate data structures necessary for telling
 * the CAM layer what operation we want to do and how to control it.
 * this is used only at user level.
 *******************************************************************************/

/* create a RF_DiskOp_t for doing a READ CAPACITY */
int rf_SCSI_AllocReadCapacity(ua_ccb_out)
  RF_DiskOp_t  **ua_ccb_out;
{
  CCB_SCSIIO         *ccb;          /* I/O command control block */
  UAGT_CAM_CCB       *ua_ccb;       /* user agent ccb for communication to CAM layer */
  ALL_REQ_SNS_DATA   *sns;          /* sense data buffer */
  DIR_READ_CAP_DATA  *dat;          /* read capacity data buffer */
  DIR_READ_CAP_CDB10 *rdcap;        /* SCSI command descriptor block (cdb) for READ CAPACITY */

#ifndef KERNEL
  RF_ALLOCATE_CCB_AND_SENSE(ua_ccb, ccb, sns);
  RF_Calloc(dat, 1, sizeof(DIR_READ_CAP_DATA), (DIR_READ_CAP_DATA *));
  rf_set_default_ccb_params(ua_ccb, ccb, sns, CAM_DIR_IN, (u_char *)dat, sizeof(DIR_READ_CAP_DATA), sizeof(DIR_READ_CAP_CDB10));

  rdcap = (DIR_READ_CAP_CDB10 *) &(ccb->cam_cdb_io.cam_cdb_bytes[0]);
  (void) bzero( (char *) rdcap, sizeof(DIR_READ_CAP_CDB10) );
  rdcap->opcode              = DIR_READCAP_OP;

  *ua_ccb_out = (RF_DiskOp_t *) ua_ccb;
#endif /* !KERNEL */
  return(0);
}

/* create a RF_DiskOp_t for doing a TEST UNIT READY */
int rf_SCSI_AllocTUR(ua_ccb_out)
  RF_DiskOp_t  **ua_ccb_out;
{
  CCB_SCSIIO         *ccb;          /* I/O command control block */
  UAGT_CAM_CCB       *ua_ccb;       /* user agent ccb for communication to CAM layer */
  ALL_REQ_SNS_DATA   *sns;          /* sense data buffer */
  ALL_TUR_CDB        *tur;          /* scsi cdb for TEST UNIT READY */

#ifndef KERNEL
  RF_ALLOCATE_CCB_AND_SENSE(ua_ccb, ccb, sns);
  rf_set_default_ccb_params(ua_ccb, ccb, sns, CAM_DIR_NONE, NULL, 0, sizeof(ALL_TUR_CDB));
  
  tur = (ALL_TUR_CDB *) &(ccb->cam_cdb_io.cam_cdb_bytes[0]);
  (void) bzero( (char *) tur, sizeof(ALL_TUR_CDB) );
  tur->opcode = ALL_TUR_OP;
  
  *ua_ccb_out = (RF_DiskOp_t *) ua_ccb;
#endif /* !KERNEL */

  return(0);
}


/********************************************************************************
 * free a previously allocated RF_DiskOp_t.  Common to all alloc routines.
 *******************************************************************************/
int rf_SCSI_FreeDiskOp(op, free_the_buf)
  RF_DiskOp_t  *op;
  int           free_the_buf;
{
#ifndef KERNEL
  UAGT_CAM_CCB *ua_ccb = (UAGT_CAM_CCB *) op;
  if (free_the_buf) {
    RF_Free(ua_ccb->uagt_buffer, ua_ccb->uagt_buflen);
  }
  RF_Free(ua_ccb->uagt_snsbuf, sizeof(ALL_REQ_SNS_DATA));
  RF_Free(ua_ccb->uagt_ccb, sizeof(CCB_SCSIIO));
  RF_Free(ua_ccb, sizeof(UAGT_CAM_CCB));
#endif /* !KERNEL */
  return(0);
}

/***************************************************************************
 *  rf_get_big_endian
 *    little-big endian conversion routine
 ***************************************************************************/
static int rf_get_big_endian(buf, length)
  unsigned char  *buf;
  int             length;
{
  register long temp = 0;
  int i;

  for(i=0; i<length; i++)
    temp = (temp << 8) | *buf++;
  return(temp);
}

/********************************************************************************
 * the next few routines actually do an operation, after it has been set up by
 * one of the allocation routines above
 ********************************************************************************/

#ifdef KERNEL
/* this gets invoked when a scsi command such as ccmn_tur completes.
 * copied from p. D-40 of device driver manual.
 */
static void rf_done(ccb)
  CCB_SCSIIO  *ccb;
{
  PDRV_DEVICE *pd;
  int s;

  pd = (PDRV_DEVICE *) ((PDRV_WS *) ccb->cam_pdrv_ptr)->pws_pdrv;
  if (!pd) RF_PANIC();
  PDRV_IPLSMP_LOCK(pd, LK_RETRY, s);
  if (!ccb->cam_req_map) {              /* not really necessary (yet) b/c we only use this for TUR and READ CAP */
    wakeup(ccb);
  }
  PDRV_IPLSMP_UNLOCK(pd, s);
}
#endif /* KERNEL */


/********************************************************************************
 * generic routine to perform an op, called from "do" routines below
 ********************************************************************************/

static int rf_do_scsi_op(dev, ua_ccb, str, max_retries)
  dev_t          dev;
  UAGT_CAM_CCB  *ua_ccb;      /* user agent ccb for comm to cam layer */
  char          *str;         /* identify what op we're doing for err report */
  int            max_retries; /* max number of allowable retries */
{
  CCB_SCSIIO *ccb = (CCB_SCSIIO *) ua_ccb->uagt_ccb;
  int status = 0;
#ifdef KERNEL
  PDRV_DEVICE *pdrv_ptr;
  pdrv_ptr = GET_PDRV_PTR(dev);
#endif /* KERNEL */

  for (; max_retries>=0; max_retries--) {

#ifndef KERNEL
    if (ioctl(camfd, UAGT_CAM_IO, (caddr_t) ua_ccb) < 0) {
      fprintf(stderr,"%s: ",str);
      perror("Error on CAM UAGT ioctl:");
      return(-1);        /* no retry in this case */
    }
    if (ccb->cam_ch.cam_status != CAM_REQ_CMP) {
      RF_ERRORMSG1("SCSI CAM error on %s\n",str);
      rf_print_ccb_status( &(ccb->cam_ch) );
      if (ccb->cam_ch.cam_status & CAM_SIM_QFRZN)
        rf_release_sim_queue(ccb);
      continue;
    } else break;
#else  /* KERNEL */
    status = ccmn_send_ccb_wait(pdrv_ptr, ccb, 0, WAIT_PRIORITY);
    if (!status) break;
#endif /* KERNEL */
    
  }
  return(status);
}


/* do a TEST UNIT READY.  bus,targ,lun is actually redundant since we have dev.