Imported Upstream version 6.1+svn3812

[mirror_smartmontools-debian.git] / os_linux.cpp

/*
 *  os_linux.cpp
 *
 * Home page of code is: http://smartmontools.sourceforge.net
 *
 * Copyright (C) 2003-11 Bruce Allen <smartmontools-support@lists.sourceforge.net>
 * Copyright (C) 2003-11 Doug Gilbert <dgilbert@interlog.com>
 * Copyright (C) 2008-12 Hank Wu <hank@areca.com.tw>
 * Copyright (C) 2008    Oliver Bock <brevilo@users.sourceforge.net>
 * Copyright (C) 2008-12 Christian Franke <smartmontools-support@lists.sourceforge.net>
 * Copyright (C) 2008    Jordan Hargrave <jordan_hargrave@dell.com>
 *
 *  Parts of this file are derived from code that was
 *
 *  Written By: Adam Radford <linux@3ware.com>
 *  Modifications By: Joel Jacobson <linux@3ware.com>
 *                   Arnaldo Carvalho de Melo <acme@conectiva.com.br>
 *                    Brad Strand <linux@3ware.com>
 *
 *  Copyright (C) 1999-2003 3ware Inc.
 *
 *  Kernel compatablity By:     Andre Hedrick <andre@suse.com>
 *  Non-Copyright (C) 2000      Andre Hedrick <andre@suse.com>
 *
 * Other ars of this file are derived from code that was
 *
 * Copyright (C) 1999-2000 Michael Cornwell <cornwell@acm.org>
 * Copyright (C) 2000 Andre Hedrick <andre@linux-ide.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * You should have received a copy of the GNU General Public License
 * (for example COPYING); If not, see <http://www.gnu.org/licenses/>.
 *
 * This code was originally developed as a Senior Thesis by Michael Cornwell
 * at the Concurrent Systems Laboratory (now part of the Storage Systems
 * Research Center), Jack Baskin School of Engineering, University of
 * California, Santa Cruz. http://ssrc.soe.ucsc.edu/
 *
 */

// This file contains the linux-specific IOCTL parts of
// smartmontools. It includes one interface routine for ATA devices,
// one for SCSI devices, and one for ATA devices behind escalade
// controllers.

#include "config.h"

#include <errno.h>
#include <fcntl.h>
#include <glob.h>

#include <scsi/scsi.h>
#include <scsi/scsi_ioctl.h>
#include <scsi/sg.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/utsname.h>
#include <unistd.h>
#include <stddef.h>  // for offsetof()
#include <sys/uio.h>
#include <sys/types.h>
#include <dirent.h>
#ifndef makedev // old versions of types.h do not include sysmacros.h
#include <sys/sysmacros.h>
#endif
#ifdef WITH_SELINUX
#include <selinux/selinux.h>
#endif

#include "int64.h"
#include "atacmds.h"
#include "os_linux.h"
#include "scsicmds.h"
#include "utility.h"
#include "cciss.h"
#include "megaraid.h"

#include "dev_interface.h"
#include "dev_ata_cmd_set.h"
#include "dev_areca.h"

#ifndef ENOTSUP
#define ENOTSUP ENOSYS
#endif

#define ARGUSED(x) ((void)(x))

const char * os_linux_cpp_cvsid = "$Id: os_linux.cpp 3738 2012-12-17 12:01:35Z samm2 $"
  OS_LINUX_H_CVSID;
extern unsigned char failuretest_permissive;

namespace os_linux { // No need to publish anything, name provided for Doxygen

/////////////////////////////////////////////////////////////////////////////
/// Shared open/close routines

class linux_smart_device
: virtual public /*implements*/ smart_device
{
public:
  explicit linux_smart_device(int flags, int retry_flags = -1)
    : smart_device(never_called),
      m_fd(-1),
      m_flags(flags), m_retry_flags(retry_flags)
      { }

  virtual ~linux_smart_device() throw();

  virtual bool is_open() const;

  virtual bool open();

  virtual bool close();

protected:
  /// Return filedesc for derived classes.
  int get_fd() const
    { return m_fd; }

  void set_fd(int fd)
    { m_fd = fd; }

private:
  int m_fd; ///< filedesc, -1 if not open.
  int m_flags; ///< Flags for ::open()
  int m_retry_flags; ///< Flags to retry ::open(), -1 if no retry
};

linux_smart_device::~linux_smart_device() throw()
{
  if (m_fd >= 0)
    ::close(m_fd);
}

bool linux_smart_device::is_open() const
{
  return (m_fd >= 0);
}

bool linux_smart_device::open()
{
  m_fd = ::open(get_dev_name(), m_flags);

  if (m_fd < 0 && errno == EROFS && m_retry_flags != -1)
    // Retry
    m_fd = ::open(get_dev_name(), m_retry_flags);

  if (m_fd < 0) {
    if (errno == EBUSY && (m_flags & O_EXCL))
      // device is locked
      return set_err(EBUSY,
        "The requested controller is used exclusively by another process!\n"
        "(e.g. smartctl or smartd)\n"
        "Please quit the impeding process or try again later...");
    return set_err((errno==ENOENT || errno==ENOTDIR) ? ENODEV : errno);
  }

  if (m_fd >= 0) {
    // sets FD_CLOEXEC on the opened device file descriptor.  The
    // descriptor is otherwise leaked to other applications (mail
    // sender) which may be considered a security risk and may result
    // in AVC messages on SELinux-enabled systems.
    if (-1 == fcntl(m_fd, F_SETFD, FD_CLOEXEC))
      // TODO: Provide an error printing routine in class smart_interface
      pout("fcntl(set  FD_CLOEXEC) failed, errno=%d [%s]\n", errno, strerror(errno));
  }

  return true;
}

// equivalent to close(file descriptor)
bool linux_smart_device::close()
{
  int fd = m_fd; m_fd = -1;
  if (::close(fd) < 0)
    return set_err(errno);
  return true;
}

// examples for smartctl
static const char  smartctl_examples[] =
		  "=================================================== SMARTCTL EXAMPLES =====\n\n"
		  "  smartctl --all /dev/hda                    (Prints all SMART information)\n\n"
		  "  smartctl --smart=on --offlineauto=on --saveauto=on /dev/hda\n"
		  "                                              (Enables SMART on first disk)\n\n"
		  "  smartctl --test=long /dev/hda          (Executes extended disk self-test)\n\n"
		  "  smartctl --attributes --log=selftest --quietmode=errorsonly /dev/hda\n"
		  "                                      (Prints Self-Test & Attribute errors)\n"
		  "  smartctl --all --device=3ware,2 /dev/sda\n"
		  "  smartctl --all --device=3ware,2 /dev/twe0\n"
		  "  smartctl --all --device=3ware,2 /dev/twa0\n"
		  "  smartctl --all --device=3ware,2 /dev/twl0\n"
		  "          (Prints all SMART info for 3rd ATA disk on 3ware RAID controller)\n"
		  "  smartctl --all --device=hpt,1/1/3 /dev/sda\n"
		  "          (Prints all SMART info for the SATA disk attached to the 3rd PMPort\n"
		  "           of the 1st channel on the 1st HighPoint RAID controller)\n"
		  "  smartctl --all --device=areca,3/1 /dev/sg2\n"
		  "          (Prints all SMART info for 3rd ATA disk of the 1st enclosure\n"
		  "           on Areca RAID controller)\n"
  ;

/////////////////////////////////////////////////////////////////////////////
/// Linux ATA support

class linux_ata_device
: public /*implements*/ ata_device_with_command_set,
  public /*extends*/ linux_smart_device
{
public:
  linux_ata_device(smart_interface * intf, const char * dev_name, const char * req_type);

protected:
  virtual int ata_command_interface(smart_command_set command, int select, char * data);
};

linux_ata_device::linux_ata_device(smart_interface * intf, const char * dev_name, const char * req_type)
: smart_device(intf, dev_name, "ata", req_type),
  linux_smart_device(O_RDONLY | O_NONBLOCK)
{
}

// PURPOSE
//   This is an interface routine meant to isolate the OS dependent
//   parts of the code, and to provide a debugging interface.  Each
//   different port and OS needs to provide it's own interface.  This
//   is the linux one.
// DETAILED DESCRIPTION OF ARGUMENTS
//   device: is the file descriptor provided by open()
//   command: defines the different operations.
//   select: additional input data if needed (which log, which type of
//           self-test).
//   data:   location to write output data, if needed (512 bytes).
//   Note: not all commands use all arguments.
// RETURN VALUES
//  -1 if the command failed
//   0 if the command succeeded,
//   STATUS_CHECK routine:
//  -1 if the command failed
//   0 if the command succeeded and disk SMART status is "OK"
//   1 if the command succeeded and disk SMART status is "FAILING"

#define BUFFER_LENGTH (4+512)

int linux_ata_device::ata_command_interface(smart_command_set command, int select, char * data)
{
  unsigned char buff[BUFFER_LENGTH];
  // positive: bytes to write to caller.  negative: bytes to READ from
  // caller. zero: non-data command
  int copydata=0;

  const int HDIO_DRIVE_CMD_OFFSET = 4;

  // See struct hd_drive_cmd_hdr in hdreg.h.  Before calling ioctl()
  // buff[0]: ATA COMMAND CODE REGISTER
  // buff[1]: ATA SECTOR NUMBER REGISTER == LBA LOW REGISTER
  // buff[2]: ATA FEATURES REGISTER
  // buff[3]: ATA SECTOR COUNT REGISTER

  // Note that on return:
  // buff[2] contains the ATA SECTOR COUNT REGISTER

  // clear out buff.  Large enough for HDIO_DRIVE_CMD (4+512 bytes)
  memset(buff, 0, BUFFER_LENGTH);

  buff[0]=ATA_SMART_CMD;
  switch (command){
  case CHECK_POWER_MODE:
    buff[0]=ATA_CHECK_POWER_MODE;
    copydata=1;
    break;
  case READ_VALUES:
    buff[2]=ATA_SMART_READ_VALUES;
    buff[3]=1;
    copydata=512;
    break;
  case READ_THRESHOLDS:
    buff[2]=ATA_SMART_READ_THRESHOLDS;
    buff[1]=buff[3]=1;
    copydata=512;
    break;
  case READ_LOG:
    buff[2]=ATA_SMART_READ_LOG_SECTOR;
    buff[1]=select;
    buff[3]=1;
    copydata=512;
    break;
  case WRITE_LOG:
    break;
  case IDENTIFY:
    buff[0]=ATA_IDENTIFY_DEVICE;
    buff[3]=1;
    copydata=512;
    break;
  case PIDENTIFY:
    buff[0]=ATA_IDENTIFY_PACKET_DEVICE;
    buff[3]=1;
    copydata=512;
    break;
  case ENABLE:
    buff[2]=ATA_SMART_ENABLE;
    buff[1]=1;
    break;
  case DISABLE:
    buff[2]=ATA_SMART_DISABLE;
    buff[1]=1;
    break;
  case STATUS:
    // this command only says if SMART is working.  It could be
    // replaced with STATUS_CHECK below.
    buff[2]=ATA_SMART_STATUS;
    break;
  case AUTO_OFFLINE:
    // NOTE: According to ATAPI 4 and UP, this command is obsolete
    // select == 241 for enable but no data transfer.  Use TASK ioctl.
    buff[1]=ATA_SMART_AUTO_OFFLINE;
    buff[2]=select;
    break;
  case AUTOSAVE:
    // select == 248 for enable but no data transfer.  Use TASK ioctl.
    buff[1]=ATA_SMART_AUTOSAVE;
    buff[2]=select;
    break;
  case IMMEDIATE_OFFLINE:
    buff[2]=ATA_SMART_IMMEDIATE_OFFLINE;
    buff[1]=select;
    break;
  case STATUS_CHECK:
    // This command uses HDIO_DRIVE_TASK and has different syntax than
    // the other commands.
    buff[1]=ATA_SMART_STATUS;
    break;
  default:
    pout("Unrecognized command %d in linux_ata_command_interface()\n"
         "Please contact " PACKAGE_BUGREPORT "\n", command);
    errno=ENOSYS;
    return -1;
  }

  // This command uses the HDIO_DRIVE_TASKFILE ioctl(). This is the
  // only ioctl() that can be used to WRITE data to the disk.
  if (command==WRITE_LOG) {
    unsigned char task[sizeof(ide_task_request_t)+512];
    ide_task_request_t *reqtask=(ide_task_request_t *) task;
    task_struct_t      *taskfile=(task_struct_t *) reqtask->io_ports;
    int retval;

    memset(task,      0, sizeof(task));

    taskfile->data           = 0;
    taskfile->feature        = ATA_SMART_WRITE_LOG_SECTOR;
    taskfile->sector_count   = 1;
    taskfile->sector_number  = select;
    taskfile->low_cylinder   = 0x4f;
    taskfile->high_cylinder  = 0xc2;
    taskfile->device_head    = 0;
    taskfile->command        = ATA_SMART_CMD;

    reqtask->data_phase      = TASKFILE_OUT;
    reqtask->req_cmd         = IDE_DRIVE_TASK_OUT;
    reqtask->out_size        = 512;
    reqtask->in_size         = 0;

    // copy user data into the task request structure
    memcpy(task+sizeof(ide_task_request_t), data, 512);

    if ((retval=ioctl(get_fd(), HDIO_DRIVE_TASKFILE, task))) {
      if (retval==-EINVAL)
        pout("Kernel lacks HDIO_DRIVE_TASKFILE support; compile kernel with CONFIG_IDE_TASKFILE_IO set\n");
      return -1;
    }
    return 0;
  }

  // There are two different types of ioctls().  The HDIO_DRIVE_TASK
  // one is this:
  if (command==STATUS_CHECK || command==AUTOSAVE || command==AUTO_OFFLINE){
    int retval;

    // NOT DOCUMENTED in /usr/src/linux/include/linux/hdreg.h. You
    // have to read the IDE driver source code.  Sigh.
    // buff[0]: ATA COMMAND CODE REGISTER
    // buff[1]: ATA FEATURES REGISTER
    // buff[2]: ATA SECTOR_COUNT
    // buff[3]: ATA SECTOR NUMBER
    // buff[4]: ATA CYL LO REGISTER
    // buff[5]: ATA CYL HI REGISTER
    // buff[6]: ATA DEVICE HEAD

    unsigned const char normal_lo=0x4f, normal_hi=0xc2;
    unsigned const char failed_lo=0xf4, failed_hi=0x2c;
    buff[4]=normal_lo;
    buff[5]=normal_hi;

    if ((retval=ioctl(get_fd(), HDIO_DRIVE_TASK, buff))) {
      if (retval==-EINVAL) {
        pout("Error SMART Status command via HDIO_DRIVE_TASK failed");
        pout("Rebuild older linux 2.2 kernels with HDIO_DRIVE_TASK support added\n");
      }
      else
        syserror("Error SMART Status command failed");
      return -1;
    }

    // Cyl low and Cyl high unchanged means "Good SMART status"
    if (buff[4]==normal_lo && buff[5]==normal_hi)
      return 0;

    // These values mean "Bad SMART status"
    if (buff[4]==failed_lo && buff[5]==failed_hi)
      return 1;

    // We haven't gotten output that makes sense; print out some debugging info
    syserror("Error SMART Status command failed");
    pout("Please get assistance from " PACKAGE_HOMEPAGE "\n");
    pout("Register values returned from SMART Status command are:\n");
    pout("ST =0x%02x\n",(int)buff[0]);
    pout("ERR=0x%02x\n",(int)buff[1]);
    pout("NS =0x%02x\n",(int)buff[2]);
    pout("SC =0x%02x\n",(int)buff[3]);
    pout("CL =0x%02x\n",(int)buff[4]);
    pout("CH =0x%02x\n",(int)buff[5]);
    pout("SEL=0x%02x\n",(int)buff[6]);
    return -1;
  }

#if 1
  // Note to people doing ports to other OSes -- don't worry about
  // this block -- you can safely ignore it.  I have put it here
  // because under linux when you do IDENTIFY DEVICE to a packet
  // device, it generates an ugly kernel syslog error message.  This
  // is harmless but frightens users.  So this block detects packet
  // devices and make IDENTIFY DEVICE fail "nicely" without a syslog
  // error message.
  //
  // If you read only the ATA specs, it appears as if a packet device
  // *might* respond to the IDENTIFY DEVICE command.  This is
  // misleading - it's because around the time that SFF-8020 was
  // incorporated into the ATA-3/4 standard, the ATA authors were
  // sloppy. See SFF-8020 and you will see that ATAPI devices have
  // *always* had IDENTIFY PACKET DEVICE as a mandatory part of their
  // command set, and return 'Command Aborted' to IDENTIFY DEVICE.
  if (command==IDENTIFY || command==PIDENTIFY){
    unsigned short deviceid[256];
    // check the device identity, as seen when the system was booted
    // or the device was FIRST registered.  This will not be current
    // if the user has subsequently changed some of the parameters. If
    // device is a packet device, swap the command interpretations.
    if (!ioctl(get_fd(), HDIO_GET_IDENTITY, deviceid) && (deviceid[0] & 0x8000))
      buff[0]=(command==IDENTIFY)?ATA_IDENTIFY_PACKET_DEVICE:ATA_IDENTIFY_DEVICE;
  }
#endif

  // We are now doing the HDIO_DRIVE_CMD type ioctl.
  if ((ioctl(get_fd(), HDIO_DRIVE_CMD, buff)))
    return -1;

  // CHECK POWER MODE command returns information in the Sector Count
  // register (buff[3]).  Copy to return data buffer.
  if (command==CHECK_POWER_MODE)
    buff[HDIO_DRIVE_CMD_OFFSET]=buff[2];

  // if the command returns data then copy it back
  if (copydata)
    memcpy(data, buff+HDIO_DRIVE_CMD_OFFSET, copydata);

  return 0;
}

// >>>>>> Start of general SCSI specific linux code

/* Linux specific code.
 * Historically smartmontools (and smartsuite before it) used the
 * SCSI_IOCTL_SEND_COMMAND ioctl which is available to all linux device
 * nodes that use the SCSI subsystem. A better interface has been available
 * via the SCSI generic (sg) driver but this involves the extra step of
 * mapping disk devices (e.g. /dev/sda) to the corresponding sg device
 * (e.g. /dev/sg2). In the linux kernel 2.6 series most of the facilities of
 * the sg driver have become available via the SG_IO ioctl which is available
 * on all SCSI devices (on SCSI tape devices from lk 2.6.6).
 * So the strategy below is to find out if the SG_IO ioctl is available and
 * if so use it; failing that use the older SCSI_IOCTL_SEND_COMMAND ioctl.
 * Should work in 2.0, 2.2, 2.4 and 2.6 series linux kernels. */

#define MAX_DXFER_LEN 1024      /* can be increased if necessary */
#define SEND_IOCTL_RESP_SENSE_LEN 16    /* ioctl limitation */
#define SG_IO_RESP_SENSE_LEN 64 /* large enough see buffer */
#define LSCSI_DRIVER_MASK  0xf /* mask out "suggestions" */
#define LSCSI_DRIVER_SENSE  0x8 /* alternate CHECK CONDITION indication */
#define LSCSI_DID_ERROR 0x7 /* Need to work around aacraid driver quirk */
#define LSCSI_DRIVER_TIMEOUT  0x6
#define LSCSI_DID_TIME_OUT  0x3
#define LSCSI_DID_BUS_BUSY  0x2
#define LSCSI_DID_NO_CONNECT  0x1

#ifndef SCSI_IOCTL_SEND_COMMAND
#define SCSI_IOCTL_SEND_COMMAND 1
#endif

#define SG_IO_PRESENT_UNKNOWN 0
#define SG_IO_PRESENT_YES 1
#define SG_IO_PRESENT_NO 2

static int sg_io_cmnd_io(int dev_fd, struct scsi_cmnd_io * iop, int report,
                         int unknown);
static int sisc_cmnd_io(int dev_fd, struct scsi_cmnd_io * iop, int report);

static int sg_io_state = SG_IO_PRESENT_UNKNOWN;

/* Preferred implementation for issuing SCSI commands in linux. This
 * function uses the SG_IO ioctl. Return 0 if command issued successfully
 * (various status values should still be checked). If the SCSI command
 * cannot be issued then a negative errno value is returned. */
static int sg_io_cmnd_io(int dev_fd, struct scsi_cmnd_io * iop, int report,
                         int unknown)
{
#ifndef SG_IO
    ARGUSED(dev_fd); ARGUSED(iop); ARGUSED(report);
    return -ENOTTY;
#else
    struct sg_io_hdr io_hdr;

    if (report > 0) {
        int k, j;
        const unsigned char * ucp = iop->cmnd;
        const char * np;
        char buff[256];
        const int sz = (int)sizeof(buff);

        np = scsi_get_opcode_name(ucp[0]);
        j = snprintf(buff, sz, " [%s: ", np ? np : "<unknown opcode>");
        for (k = 0; k < (int)iop->cmnd_len; ++k)
            j += snprintf(&buff[j], (sz > j ? (sz - j) : 0), "%02x ", ucp[k]);
        if ((report > 1) &&
            (DXFER_TO_DEVICE == iop->dxfer_dir) && (iop->dxferp)) {
            int trunc = (iop->dxfer_len > 256) ? 1 : 0;

            j += snprintf(&buff[j], (sz > j ? (sz - j) : 0), "]\n  Outgoing "
                          "data, len=%d%s:\n", (int)iop->dxfer_len,
                          (trunc ? " [only first 256 bytes shown]" : ""));
            dStrHex((const char *)iop->dxferp,
                    (trunc ? 256 : iop->dxfer_len) , 1);
        }
        else
            j += snprintf(&buff[j], (sz > j ? (sz - j) : 0), "]\n");
        pout("%s", buff);
    }
    memset(&io_hdr, 0, sizeof(struct sg_io_hdr));
    io_hdr.interface_id = 'S';
    io_hdr.cmd_len = iop->cmnd_len;
    io_hdr.mx_sb_len = iop->max_sense_len;
    io_hdr.dxfer_len = iop->dxfer_len;
    io_hdr.dxferp = iop->dxferp;
    io_hdr.cmdp = iop->cmnd;
    io_hdr.sbp = iop->sensep;
    /* sg_io_hdr interface timeout has millisecond units. Timeout of 0
       defaults to 60 seconds. */
    io_hdr.timeout = ((0 == iop->timeout) ? 60 : iop->timeout) * 1000;
    switch (iop->dxfer_dir) {
        case DXFER_NONE:
            io_hdr.dxfer_direction = SG_DXFER_NONE;
            break;
        case DXFER_FROM_DEVICE:
            io_hdr.dxfer_direction = SG_DXFER_FROM_DEV;
            break;
        case DXFER_TO_DEVICE:
            io_hdr.dxfer_direction = SG_DXFER_TO_DEV;
            break;
        default:
            pout("do_scsi_cmnd_io: bad dxfer_dir\n");
            return -EINVAL;
    }
    iop->resp_sense_len = 0;
    iop->scsi_status = 0;
    iop->resid = 0;
    if (ioctl(dev_fd, SG_IO, &io_hdr) < 0) {
        if (report && (! unknown))
            pout("  SG_IO ioctl failed, errno=%d [%s]\n", errno,
                 strerror(errno));
        return -errno;
    }
    iop->resid = io_hdr.resid;
    iop->scsi_status = io_hdr.status;
    if (report > 0) {
        pout("  scsi_status=0x%x, host_status=0x%x, driver_status=0x%x\n"
             "  info=0x%x  duration=%d milliseconds  resid=%d\n", io_hdr.status,
             io_hdr.host_status, io_hdr.driver_status, io_hdr.info,
             io_hdr.duration, io_hdr.resid);
        if (report > 1) {
            if (DXFER_FROM_DEVICE == iop->dxfer_dir) {
                int trunc, len;

		len = iop->dxfer_len - iop->resid;
		trunc = (len > 256) ? 1 : 0;
                if (len > 0) {
                    pout("  Incoming data, len=%d%s:\n", len,
                         (trunc ? " [only first 256 bytes shown]" : ""));
                    dStrHex((const char*)iop->dxferp, (trunc ? 256 : len),
                            1);
                } else
                    pout("  Incoming data trimmed to nothing by resid\n");
            }
        }
    }

    if (io_hdr.info & SG_INFO_CHECK) { /* error or warning */
        int masked_driver_status = (LSCSI_DRIVER_MASK & io_hdr.driver_status);

        if (0 != io_hdr.host_status) {
            if ((LSCSI_DID_NO_CONNECT == io_hdr.host_status) ||
                (LSCSI_DID_BUS_BUSY == io_hdr.host_status) ||
                (LSCSI_DID_TIME_OUT == io_hdr.host_status))
                return -ETIMEDOUT;
            else
               /* Check for DID_ERROR - workaround for aacraid driver quirk */
               if (LSCSI_DID_ERROR != io_hdr.host_status) {
                       return -EIO; /* catch all if not DID_ERR */
               }
        }
        if (0 != masked_driver_status) {
            if (LSCSI_DRIVER_TIMEOUT == masked_driver_status)
                return -ETIMEDOUT;
            else if (LSCSI_DRIVER_SENSE != masked_driver_status)
                return -EIO;
        }
        if (LSCSI_DRIVER_SENSE == masked_driver_status)
            iop->scsi_status = SCSI_STATUS_CHECK_CONDITION;
        iop->resp_sense_len = io_hdr.sb_len_wr;
        if ((SCSI_STATUS_CHECK_CONDITION == iop->scsi_status) &&
            iop->sensep && (iop->resp_sense_len > 0)) {
            if (report > 1) {
                pout("  >>> Sense buffer, len=%d:\n",
                     (int)iop->resp_sense_len);
                dStrHex((const char *)iop->sensep, iop->resp_sense_len , 1);
            }
        }
        if (report) {
            if (SCSI_STATUS_CHECK_CONDITION == iop->scsi_status) {
                if ((iop->sensep[0] & 0x7f) > 0x71)
                    pout("  status=%x: [desc] sense_key=%x asc=%x ascq=%x\n",
                         iop->scsi_status, iop->sensep[1] & 0xf,
                         iop->sensep[2], iop->sensep[3]);
                else
                    pout("  status=%x: sense_key=%x asc=%x ascq=%x\n",
                         iop->scsi_status, iop->sensep[2] & 0xf,
                         iop->sensep[12], iop->sensep[13]);
            }
            else
                pout("  status=0x%x\n", iop->scsi_status);
        }
    }
    return 0;
#endif
}

struct linux_ioctl_send_command
{
    int inbufsize;
    int outbufsize;
    UINT8 buff[MAX_DXFER_LEN + 16];
};

/* The Linux SCSI_IOCTL_SEND_COMMAND ioctl is primitive and it doesn't
 * support: CDB length (guesses it from opcode), resid and timeout.
 * Patches in Linux 2.4.21 and 2.5.70 to extend SEND DIAGNOSTIC timeout
 * to 2 hours in order to allow long foreground extended self tests. */
static int sisc_cmnd_io(int dev_fd, struct scsi_cmnd_io * iop, int report)
{
    struct linux_ioctl_send_command wrk;
    int status, buff_offset;
    size_t len;

    memcpy(wrk.buff, iop->cmnd, iop->cmnd_len);
    buff_offset = iop->cmnd_len;
    if (report > 0) {
        int k, j;
        const unsigned char * ucp = iop->cmnd;
        const char * np;
        char buff[256];
        const int sz = (int)sizeof(buff);

        np = scsi_get_opcode_name(ucp[0]);
        j = snprintf(buff, sz, " [%s: ", np ? np : "<unknown opcode>");
        for (k = 0; k < (int)iop->cmnd_len; ++k)
            j += snprintf(&buff[j], (sz > j ? (sz - j) : 0), "%02x ", ucp[k]);
        if ((report > 1) &&
            (DXFER_TO_DEVICE == iop->dxfer_dir) && (iop->dxferp)) {
            int trunc = (iop->dxfer_len > 256) ? 1 : 0;

            j += snprintf(&buff[j], (sz > j ? (sz - j) : 0), "]\n  Outgoing "
                          "data, len=%d%s:\n", (int)iop->dxfer_len,
                          (trunc ? " [only first 256 bytes shown]" : ""));
            dStrHex((const char *)iop->dxferp,
                    (trunc ? 256 : iop->dxfer_len) , 1);
        }
        else
            j += snprintf(&buff[j], (sz > j ? (sz - j) : 0), "]\n");
        pout("%s", buff);
    }
    switch (iop->dxfer_dir) {
        case DXFER_NONE:
            wrk.inbufsize = 0;
            wrk.outbufsize = 0;
            break;
        case DXFER_FROM_DEVICE:
            wrk.inbufsize = 0;
            if (iop->dxfer_len > MAX_DXFER_LEN)
                return -EINVAL;
            wrk.outbufsize = iop->dxfer_len;
            break;
        case DXFER_TO_DEVICE:
            if (iop->dxfer_len > MAX_DXFER_LEN)
                return -EINVAL;
            memcpy(wrk.buff + buff_offset, iop->dxferp, iop->dxfer_len);
            wrk.inbufsize = iop->dxfer_len;
            wrk.outbufsize = 0;
            break;
        default:
            pout("do_scsi_cmnd_io: bad dxfer_dir\n");
            return -EINVAL;
    }
    iop->resp_sense_len = 0;
    iop->scsi_status = 0;
    iop->resid = 0;
    status = ioctl(dev_fd, SCSI_IOCTL_SEND_COMMAND, &wrk);
    if (-1 == status) {
        if (report)
            pout("  SCSI_IOCTL_SEND_COMMAND ioctl failed, errno=%d [%s]\n",
                 errno, strerror(errno));
        return -errno;
    }
    if (0 == status) {
        if (report > 0)
            pout("  status=0\n");
        if (DXFER_FROM_DEVICE == iop->dxfer_dir) {
            memcpy(iop->dxferp, wrk.buff, iop->dxfer_len);
            if (report > 1) {
                int trunc = (iop->dxfer_len > 256) ? 1 : 0;

                pout("  Incoming data, len=%d%s:\n", (int)iop->dxfer_len,
                     (trunc ? " [only first 256 bytes shown]" : ""));
                dStrHex((const char*)iop->dxferp,
                        (trunc ? 256 : iop->dxfer_len) , 1);
            }
        }
        return 0;
    }
    iop->scsi_status = status & 0x7e; /* bits 0 and 7 used to be for vendors */
    if (LSCSI_DRIVER_SENSE == ((status >> 24) & 0xf))
        iop->scsi_status = SCSI_STATUS_CHECK_CONDITION;
    len = (SEND_IOCTL_RESP_SENSE_LEN < iop->max_sense_len) ?
                SEND_IOCTL_RESP_SENSE_LEN : iop->max_sense_len;
    if ((SCSI_STATUS_CHECK_CONDITION == iop->scsi_status) &&
        iop->sensep && (len > 0)) {
        memcpy(iop->sensep, wrk.buff, len);
        iop->resp_sense_len = len;
        if (report > 1) {
            pout("  >>> Sense buffer, len=%d:\n", (int)len);
            dStrHex((const char *)wrk.buff, len , 1);
        }
    }
    if (report) {
        if (SCSI_STATUS_CHECK_CONDITION == iop->scsi_status) {
            pout("  status=%x: sense_key=%x asc=%x ascq=%x\n", status & 0xff,
                 wrk.buff[2] & 0xf, wrk.buff[12], wrk.buff[13]);
        }
        else
            pout("  status=0x%x\n", status);
    }
    if (iop->scsi_status > 0)
        return 0;
    else {
        if (report > 0)
            pout("  ioctl status=0x%x but scsi status=0, fail with EIO\n",
                 status);
        return -EIO;      /* give up, assume no device there */
    }
}

/* SCSI command transmission interface function, linux version.
 * Returns 0 if SCSI command successfully launched and response
 * received. Even when 0 is returned the caller should check
 * scsi_cmnd_io::scsi_status for SCSI defined errors and warnings
 * (e.g. CHECK CONDITION). If the SCSI command could not be issued
 * (e.g. device not present or timeout) or some other problem
 * (e.g. timeout) then returns a negative errno value */
static int do_normal_scsi_cmnd_io(int dev_fd, struct scsi_cmnd_io * iop,
                                  int report)
{
    int res;

    /* implementation relies on static sg_io_state variable. If not
     * previously set tries the SG_IO ioctl. If that succeeds assume
     * that SG_IO ioctl functional. If it fails with an errno value
     * other than ENODEV (no device) or permission then assume
     * SCSI_IOCTL_SEND_COMMAND is the only option. */
    switch (sg_io_state) {
    case SG_IO_PRESENT_UNKNOWN:
        /* ignore report argument */
        if (0 == (res = sg_io_cmnd_io(dev_fd, iop, report, 1))) {
            sg_io_state = SG_IO_PRESENT_YES;
            return 0;
        } else if ((-ENODEV == res) || (-EACCES == res) || (-EPERM == res))
            return res;         /* wait until we see a device */
        sg_io_state = SG_IO_PRESENT_NO;
        /* drop through by design */
    case SG_IO_PRESENT_NO:
        return sisc_cmnd_io(dev_fd, iop, report);
    case SG_IO_PRESENT_YES:
        return sg_io_cmnd_io(dev_fd, iop, report, 0);
    default:
        pout(">>>> do_scsi_cmnd_io: bad sg_io_state=%d\n", sg_io_state);
        sg_io_state = SG_IO_PRESENT_UNKNOWN;
        return -EIO;    /* report error and reset state */
    }
}

// >>>>>> End of general SCSI specific linux code

/////////////////////////////////////////////////////////////////////////////
/// Standard SCSI support

class linux_scsi_device
: public /*implements*/ scsi_device,
  public /*extends*/ linux_smart_device
{
public:
  linux_scsi_device(smart_interface * intf, const char * dev_name,
                    const char * req_type, bool scanning = false);

  virtual smart_device * autodetect_open();

  virtual bool scsi_pass_through(scsi_cmnd_io * iop);

private:
  bool m_scanning; ///< true if created within scan_smart_devices
};

linux_scsi_device::linux_scsi_device(smart_interface * intf,
  const char * dev_name, const char * req_type, bool scanning /*= false*/)
: smart_device(intf, dev_name, "scsi", req_type),
  // If opened with O_RDWR, a SATA disk in standby mode
  // may spin-up after device close().
  linux_smart_device(O_RDONLY | O_NONBLOCK),
  m_scanning(scanning)
{
}

bool linux_scsi_device::scsi_pass_through(scsi_cmnd_io * iop)
{
  int status = do_normal_scsi_cmnd_io(get_fd(), iop, scsi_debugmode);
  if (status < 0)
      return set_err(-status);
  return true;
}

/////////////////////////////////////////////////////////////////////////////
/// LSI MegaRAID support

class linux_megaraid_device
: public /* implements */ scsi_device,
  public /* extends */ linux_smart_device
{
public:
  linux_megaraid_device(smart_interface *intf, const char *name, 
    unsigned int bus, unsigned int tgt);

  virtual ~linux_megaraid_device() throw();

  virtual smart_device * autodetect_open();

  virtual bool open();
  virtual bool close();

  virtual bool scsi_pass_through(scsi_cmnd_io *iop);

private:
  unsigned int m_disknum;
  unsigned int m_busnum;
  unsigned int m_hba;
  int m_fd;

  bool (linux_megaraid_device::*pt_cmd)(int cdblen, void *cdb, int dataLen, void *data,
    int senseLen, void *sense, int report, int direction);
  bool megasas_cmd(int cdbLen, void *cdb, int dataLen, void *data,
    int senseLen, void *sense, int report, int direction);
  bool megadev_cmd(int cdbLen, void *cdb, int dataLen, void *data,
    int senseLen, void *sense, int report, int direction);
};

linux_megaraid_device::linux_megaraid_device(smart_interface *intf,
  const char *dev_name, unsigned int bus, unsigned int tgt)
 : smart_device(intf, dev_name, "megaraid", "megaraid"),
   linux_smart_device(O_RDWR | O_NONBLOCK),
   m_disknum(tgt), m_busnum(bus), m_hba(0),
   m_fd(-1), pt_cmd(0)
{
  set_info().info_name = strprintf("%s [megaraid_disk_%02d]", dev_name, m_disknum);
  set_info().dev_type = strprintf("megaraid,%d", tgt);
}

linux_megaraid_device::~linux_megaraid_device() throw()
{
  if (m_fd >= 0)
    ::close(m_fd);
}

smart_device * linux_megaraid_device::autodetect_open()
{
  int report = scsi_debugmode;

  // Open device
  if (!open())
    return this;

  // The code below is based on smartd.cpp:SCSIFilterKnown()
  if (strcmp(get_req_type(), "megaraid"))
    return this;

  // Get INQUIRY
  unsigned char req_buff[64] = {0, };
  int req_len = 36;
  if (scsiStdInquiry(this, req_buff, req_len)) {
      close();
      set_err(EIO, "INQUIRY failed");
      return this;
  }

  int avail_len = req_buff[4] + 5;
  int len = (avail_len < req_len ? avail_len : req_len);
  if (len < 36)
      return this;

  if (report)
    pout("Got MegaRAID inquiry.. %s\n", req_buff+8);

  // Use INQUIRY to detect type
  {
    // SAT?
    ata_device * newdev = smi()->autodetect_sat_device(this, req_buff, len);
    if (newdev) // NOTE: 'this' is now owned by '*newdev'
      return newdev;
  }

  // Nothing special found
  return this;
}

bool linux_megaraid_device::open()
{
  char line[128];
  int   mjr;
  int report = scsi_debugmode;

  if(sscanf(get_dev_name(),"/dev/bus/%d", &m_hba) == 0) {
    if (!linux_smart_device::open())
      return false;
    /* Get device HBA */
    struct sg_scsi_id sgid;
    if (ioctl(get_fd(), SG_GET_SCSI_ID, &sgid) == 0) {
      m_hba = sgid.host_no;
    }
    else if (ioctl(get_fd(), SCSI_IOCTL_GET_BUS_NUMBER, &m_hba) != 0) {
      int err = errno;
      linux_smart_device::close();
      return set_err(err, "can't get bus number");
    } // we dont need this device anymore
    linux_smart_device::close();
  }
  /* Perform mknod of device ioctl node */
  FILE * fp = fopen("/proc/devices", "r");
  while (fgets(line, sizeof(line), fp) != NULL) {
    int n1 = 0;
    if (sscanf(line, "%d megaraid_sas_ioctl%n", &mjr, &n1) == 1 && n1 == 22) {
      n1=mknod("/dev/megaraid_sas_ioctl_node", S_IFCHR, makedev(mjr, 0));
      if(report > 0)
        pout("Creating /dev/megaraid_sas_ioctl_node = %d\n", n1 >= 0 ? 0 : errno);
      if (n1 >= 0 || errno == EEXIST)
        break;
    }
    else if (sscanf(line, "%d megadev%n", &mjr, &n1) == 1 && n1 == 11) {
      n1=mknod("/dev/megadev0", S_IFCHR, makedev(mjr, 0));
      if(report > 0)
        pout("Creating /dev/megadev0 = %d\n", n1 >= 0 ? 0 : errno);
      if (n1 >= 0 || errno == EEXIST)
        break;
    }
  }
  fclose(fp);

  /* Open Device IOCTL node */
  if ((m_fd = ::open("/dev/megaraid_sas_ioctl_node", O_RDWR)) >= 0) {
    pt_cmd = &linux_megaraid_device::megasas_cmd;
  }
  else if ((m_fd = ::open("/dev/megadev0", O_RDWR)) >= 0) {
    pt_cmd = &linux_megaraid_device::megadev_cmd;
  }
  else {
    int err = errno;
    linux_smart_device::close();
    return set_err(err, "cannot open /dev/megaraid_sas_ioctl_node or /dev/megadev0");
  }
  set_fd(m_fd);
  return true;
}

bool linux_megaraid_device::close()
{
  if (m_fd >= 0)
    ::close(m_fd);
  m_fd = -1; m_hba = 0; pt_cmd = 0;
  set_fd(m_fd);
  return true;
}

bool linux_megaraid_device::scsi_pass_through(scsi_cmnd_io *iop)
{
  int report = scsi_debugmode;

  if (report > 0) {
        int k, j;
        const unsigned char * ucp = iop->cmnd;
        const char * np;
        char buff[256];
        const int sz = (int)sizeof(buff);

        np = scsi_get_opcode_name(ucp[0]);
        j = snprintf(buff, sz, " [%s: ", np ? np : "<unknown opcode>");
        for (k = 0; k < (int)iop->cmnd_len; ++k)
            j += snprintf(&buff[j], (sz > j ? (sz - j) : 0), "%02x ", ucp[k]);
        if ((report > 1) &&
            (DXFER_TO_DEVICE == iop->dxfer_dir) && (iop->dxferp)) {
            int trunc = (iop->dxfer_len > 256) ? 1 : 0;

            j += snprintf(&buff[j], (sz > j ? (sz - j) : 0), "]\n  Outgoing "
                          "data, len=%d%s:\n", (int)iop->dxfer_len,
                          (trunc ? " [only first 256 bytes shown]" : ""));
            dStrHex((const char *)iop->dxferp,
                    (trunc ? 256 : iop->dxfer_len) , 1);
        }
        else
            j += snprintf(&buff[j], (sz > j ? (sz - j) : 0), "]\n");
        pout("%s", buff);
  }

  // Controller rejects Test Unit Ready
  if (iop->cmnd[0] == 0x00)
    return true;

  if (iop->cmnd[0] == SAT_ATA_PASSTHROUGH_12 || iop->cmnd[0] == SAT_ATA_PASSTHROUGH_16) { 
    // Controller does not return ATA output registers in SAT sense data
    if (iop->cmnd[2] & (1 << 5)) // chk_cond
      return set_err(ENOSYS, "ATA return descriptor not supported by controller firmware");
  }
  // SMART WRITE LOG SECTOR causing media errors
  if ((iop->cmnd[0] == SAT_ATA_PASSTHROUGH_16 // SAT16 WRITE LOG
      && iop->cmnd[14] == ATA_SMART_CMD && iop->cmnd[3]==0 && iop->cmnd[4] == ATA_SMART_WRITE_LOG_SECTOR) ||
      (iop->cmnd[0] == SAT_ATA_PASSTHROUGH_12 // SAT12 WRITE LOG
       && iop->cmnd[9] == ATA_SMART_CMD && iop->cmnd[3] == ATA_SMART_WRITE_LOG_SECTOR)) 
  {
    if(!failuretest_permissive)
       return set_err(ENOSYS, "SMART WRITE LOG SECTOR may cause problems, try with -T permissive to force"); 
  }
  if (pt_cmd == NULL)
    return false;
  return (this->*pt_cmd)(iop->cmnd_len, iop->cmnd,
    iop->dxfer_len, iop->dxferp,
    iop->max_sense_len, iop->sensep, report, iop->dxfer_dir);
}

/* Issue passthrough scsi command to PERC5/6 controllers */
bool linux_megaraid_device::megasas_cmd(int cdbLen, void *cdb, 
  int dataLen, void *data,
  int /*senseLen*/, void * /*sense*/, int /*report*/, int dxfer_dir)
{
  struct megasas_pthru_frame	*pthru;
  struct megasas_iocpacket	uio;
  int rc;

  memset(&uio, 0, sizeof(uio));
  pthru = &uio.frame.pthru;
  pthru->cmd = MFI_CMD_PD_SCSI_IO;
  pthru->cmd_status = 0xFF;
  pthru->scsi_status = 0x0;
  pthru->target_id = m_disknum;
  pthru->lun = 0;
  pthru->cdb_len = cdbLen;
  pthru->timeout = 0;
  switch (dxfer_dir) {
    case DXFER_NONE:
      pthru->flags = MFI_FRAME_DIR_NONE;
      break;
    case DXFER_FROM_DEVICE:
      pthru->flags = MFI_FRAME_DIR_READ;
      break;
    case DXFER_TO_DEVICE:
      pthru->flags = MFI_FRAME_DIR_WRITE;
      break;
    default:
      pout("megasas_cmd: bad dxfer_dir\n");
      return set_err(EINVAL, "megasas_cmd: bad dxfer_dir\n");
  }

  if (dataLen > 0) {
    pthru->sge_count = 1;
    pthru->data_xfer_len = dataLen;
    pthru->sgl.sge32[0].phys_addr = (intptr_t)data;
    pthru->sgl.sge32[0].length = (uint32_t)dataLen;
  }
  memcpy(pthru->cdb, cdb, cdbLen);

  uio.host_no = m_hba;
  if (dataLen > 0) {
    uio.sge_count = 1;
    uio.sgl_off = offsetof(struct megasas_pthru_frame, sgl);
    uio.sgl[0].iov_base = data;
    uio.sgl[0].iov_len = dataLen;
  }

  rc = 0;
  errno = 0;
  rc = ioctl(m_fd, MEGASAS_IOC_FIRMWARE, &uio);
  if (pthru->cmd_status || rc != 0) {
    if (pthru->cmd_status == 12) {
      return set_err(EIO, "megasas_cmd: Device %d does not exist\n", m_disknum);
    }
    return set_err((errno ? errno : EIO), "megasas_cmd result: %d.%d = %d/%d",
                   m_hba, m_disknum, errno,
                   pthru->cmd_status);
  }
  return true;
}

/* Issue passthrough scsi commands to PERC2/3/4 controllers */
bool linux_megaraid_device::megadev_cmd(int cdbLen, void *cdb, 
  int dataLen, void *data,
  int /*senseLen*/, void * /*sense*/, int /*report*/, int /* dir */)
{
  struct uioctl_t uio;
  int rc;

  /* Don't issue to the controller */
  if (m_disknum == 7)
    return false;

  memset(&uio, 0, sizeof(uio));
  uio.inlen  = dataLen;
  uio.outlen = dataLen;

  memset(data, 0, dataLen);
  uio.ui.fcs.opcode = 0x80;             // M_RD_IOCTL_CMD
  uio.ui.fcs.adapno = MKADAP(m_hba);

  uio.data.pointer = (uint8_t *)data;

  uio.mbox.cmd = MEGA_MBOXCMD_PASSTHRU;
  uio.mbox.xferaddr = (intptr_t)&uio.pthru;

  uio.pthru.ars     = 1;
  uio.pthru.timeout = 2;
  uio.pthru.channel = 0;
  uio.pthru.target  = m_disknum;
  uio.pthru.cdblen  = cdbLen;
  uio.pthru.reqsenselen  = MAX_REQ_SENSE_LEN;
  uio.pthru.dataxferaddr = (intptr_t)data;
  uio.pthru.dataxferlen  = dataLen;
  memcpy(uio.pthru.cdb, cdb, cdbLen);

  rc=ioctl(m_fd, MEGAIOCCMD, &uio);
  if (uio.pthru.scsistatus || rc != 0) {
    return set_err((errno ? errno : EIO), "megadev_cmd result: %d.%d =  %d/%d",
                   m_hba, m_disknum, errno,
                   uio.pthru.scsistatus);
  }
  return true;
}

/////////////////////////////////////////////////////////////////////////////
/// CCISS RAID support

#ifdef HAVE_LINUX_CCISS_IOCTL_H

class linux_cciss_device
: public /*implements*/ scsi_device,
  public /*extends*/ linux_smart_device
{
public:
  linux_cciss_device(smart_interface * intf, const char * name, unsigned char disknum);

  virtual bool scsi_pass_through(scsi_cmnd_io * iop);

private:
  unsigned char m_disknum; ///< Disk number.
};

linux_cciss_device::linux_cciss_device(smart_interface * intf,
  const char * dev_name, unsigned char disknum)
: smart_device(intf, dev_name, "cciss", "cciss"),
  linux_smart_device(O_RDWR | O_NONBLOCK),
  m_disknum(disknum)
{
  set_info().info_name = strprintf("%s [cciss_disk_%02d]", dev_name, disknum);
}

bool linux_cciss_device::scsi_pass_through(scsi_cmnd_io * iop)
{
  int status = cciss_io_interface(get_fd(), m_disknum, iop, scsi_debugmode);
  if (status < 0)
      return set_err(-status);
  return true;
}

#endif // HAVE_LINUX_CCISS_IOCTL_H

/////////////////////////////////////////////////////////////////////////////
/// AMCC/3ware RAID support

class linux_escalade_device
: public /*implements*/ ata_device,
  public /*extends*/ linux_smart_device
{
public:
  enum escalade_type_t {
    AMCC_3WARE_678K,
    AMCC_3WARE_678K_CHAR,
    AMCC_3WARE_9000_CHAR,
    AMCC_3WARE_9700_CHAR
  };

  linux_escalade_device(smart_interface * intf, const char * dev_name,
    escalade_type_t escalade_type, int disknum);

  virtual bool open();

  virtual bool ata_pass_through(const ata_cmd_in & in, ata_cmd_out & out);

private:
  escalade_type_t m_escalade_type; ///< Controller type
  int m_disknum; ///< Disk number.
};

linux_escalade_device::linux_escalade_device(smart_interface * intf, const char * dev_name,
    escalade_type_t escalade_type, int disknum)
: smart_device(intf, dev_name, "3ware", "3ware"),
  linux_smart_device(O_RDONLY | O_NONBLOCK),
  m_escalade_type(escalade_type), m_disknum(disknum)
{
  set_info().info_name = strprintf("%s [3ware_disk_%02d]", dev_name, disknum);
}

/* This function will setup and fix device nodes for a 3ware controller. */
#define MAJOR_STRING_LENGTH 3
#define DEVICE_STRING_LENGTH 32
#define NODE_STRING_LENGTH 16
static int setup_3ware_nodes(const char *nodename, const char *driver_name)
{
  int              tw_major      = 0;
  int              index         = 0;
  char             majorstring[MAJOR_STRING_LENGTH+1];
  char             device_name[DEVICE_STRING_LENGTH+1];
  char             nodestring[NODE_STRING_LENGTH];
  struct stat      stat_buf;
  FILE             *file;
  int              retval = 0;
#ifdef WITH_SELINUX
  security_context_t orig_context = NULL;
  security_context_t node_context = NULL;
  int                selinux_enabled  = is_selinux_enabled();
  int                selinux_enforced = security_getenforce();
#endif

  /* First try to open up /proc/devices */
  if (!(file = fopen("/proc/devices", "r"))) {
    pout("Error opening /proc/devices to check/create 3ware device nodes\n");
    syserror("fopen");
    return 0;  // don't fail here: user might not have /proc !
  }

  /* Attempt to get device major number */
  while (EOF != fscanf(file, "%3s %32s", majorstring, device_name)) {
    majorstring[MAJOR_STRING_LENGTH]='\0';
    device_name[DEVICE_STRING_LENGTH]='\0';
    if (!strncmp(device_name, nodename, DEVICE_STRING_LENGTH)) {
      tw_major = atoi(majorstring);
      break;
    }
  }
  fclose(file);

  /* See if we found a major device number */
  if (!tw_major) {
    pout("No major number for /dev/%s listed in /proc/devices. Is the %s driver loaded?\n", nodename, driver_name);
    return 2;
  }
#ifdef WITH_SELINUX
  /* Prepare a database of contexts for files in /dev
   * and save the current context */
  if (selinux_enabled) {
    if (matchpathcon_init_prefix(NULL, "/dev") < 0)
      pout("Error initializing contexts database for /dev");
    if (getfscreatecon(&orig_context) < 0) {
      pout("Error retrieving original SELinux fscreate context");
      if (selinux_enforced)
        matchpathcon_fini();
        return 6;
      }
  }
#endif
  /* Now check if nodes are correct */
  for (index=0; index<16; index++) {
    snprintf(nodestring, sizeof(nodestring), "/dev/%s%d", nodename, index);
#ifdef WITH_SELINUX
    /* Get context of the node and set it as the default */
    if (selinux_enabled) {
      if (matchpathcon(nodestring, S_IRUSR | S_IWUSR, &node_context) < 0) {
        pout("Could not retrieve context for %s", nodestring);
        if (selinux_enforced) {
          retval = 6;
          break;
        }
      }
      if (setfscreatecon(node_context) < 0) {
        pout ("Error setting default fscreate context");
        if (selinux_enforced) {
          retval = 6;
          break;
        }
      }
    }
#endif
    /* Try to stat the node */
    if ((stat(nodestring, &stat_buf))) {
      pout("Node %s does not exist and must be created. Check the udev rules.\n", nodestring);
      /* Create a new node if it doesn't exist */
      if (mknod(nodestring, S_IFCHR|0600, makedev(tw_major, index))) {
        pout("problem creating 3ware device nodes %s", nodestring);
        syserror("mknod");
        retval = 3;
        break;
      } else {
#ifdef WITH_SELINUX
	if (selinux_enabled && node_context) {
	  freecon(node_context);
	  node_context = NULL;
	}
#endif
        continue;
      }
    }

    /* See if nodes major and minor numbers are correct */
    if ((tw_major != (int)(major(stat_buf.st_rdev))) ||
        (index    != (int)(minor(stat_buf.st_rdev))) ||
        (!S_ISCHR(stat_buf.st_mode))) {
      pout("Node %s has wrong major/minor number and must be created anew."
          " Check the udev rules.\n", nodestring);
      /* Delete the old node */
      if (unlink(nodestring)) {
        pout("problem unlinking stale 3ware device node %s", nodestring);
        syserror("unlink");
        retval = 4;
        break;
      }

      /* Make a new node */
      if (mknod(nodestring, S_IFCHR|0600, makedev(tw_major, index))) {
        pout("problem creating 3ware device nodes %s", nodestring);
        syserror("mknod");
        retval = 5;
        break;
      }
    }
#ifdef WITH_SELINUX
    if (selinux_enabled && node_context) {
      freecon(node_context);
      node_context = NULL;
    }
#endif
  }

#ifdef WITH_SELINUX
  if (selinux_enabled) {
    if(setfscreatecon(orig_context) < 0) {
      pout("Error re-setting original fscreate context");
      if (selinux_enforced)
        retval = 6;
    }
    if(orig_context)
      freecon(orig_context);
    if(node_context)
      freecon(node_context);
    matchpathcon_fini();
  }
#endif
  return retval;
}

bool linux_escalade_device::open()
{
  if (m_escalade_type == AMCC_3WARE_9700_CHAR || m_escalade_type == AMCC_3WARE_9000_CHAR ||
      m_escalade_type == AMCC_3WARE_678K_CHAR) {
    // the device nodes for these controllers are dynamically assigned,
    // so we need to check that they exist with the correct major
    // numbers and if not, create them
    const char * node   = (m_escalade_type == AMCC_3WARE_9700_CHAR ? "twl"     :
                           m_escalade_type == AMCC_3WARE_9000_CHAR ? "twa"     :
                                                                     "twe"      );
    const char * driver = (m_escalade_type == AMCC_3WARE_9700_CHAR ? "3w-sas"  :
                           m_escalade_type == AMCC_3WARE_9000_CHAR ? "3w-9xxx" :
                                                                     "3w-xxxx"  );
    if (setup_3ware_nodes(node, driver))
      return set_err((errno ? errno : ENXIO), "setup_3ware_nodes(\"%s\", \"%s\") failed", node, driver);
  }
  // Continue with default open
  return linux_smart_device::open();
}

// TODO: Function no longer useful
//void printwarning(smart_command_set command);

// PURPOSE
//   This is an interface routine meant to isolate the OS dependent
//   parts of the code, and to provide a debugging interface.  Each
//   different port and OS needs to provide it's own interface.  This
//   is the linux interface to the 3ware 3w-xxxx driver.  It allows ATA
//   commands to be passed through the SCSI driver.
// DETAILED DESCRIPTION OF ARGUMENTS
//   fd: is the file descriptor provided by open()
//   disknum is the disk number (0 to 15) in the RAID array
//   escalade_type indicates the type of controller type, and if scsi or char interface is used
//   command: defines the different operations.
//   select: additional input data if needed (which log, which type of
//           self-test).
//   data:   location to write output data, if needed (512 bytes).
//   Note: not all commands use all arguments.
// RETURN VALUES
//  -1 if the command failed
//   0 if the command succeeded,
//   STATUS_CHECK routine:
//  -1 if the command failed
//   0 if the command succeeded and disk SMART status is "OK"
//   1 if the command succeeded and disk SMART status is "FAILING"

/* 512 is the max payload size: increase if needed */
#define BUFFER_LEN_678K      ( sizeof(TW_Ioctl)                  ) // 1044 unpacked, 1041 packed
#define BUFFER_LEN_678K_CHAR ( sizeof(TW_New_Ioctl)+512-1        ) // 1539 unpacked, 1536 packed
#define BUFFER_LEN_9000      ( sizeof(TW_Ioctl_Buf_Apache)+512-1 ) // 2051 unpacked, 2048 packed
#define TW_IOCTL_BUFFER_SIZE ( MAX(MAX(BUFFER_LEN_678K, BUFFER_LEN_9000), BUFFER_LEN_678K_CHAR) )

bool linux_escalade_device::ata_pass_through(const ata_cmd_in & in, ata_cmd_out & out)
{
  if (!ata_cmd_is_ok(in,
    true, // data_out_support
    false, // TODO: multi_sector_support
    true) // ata_48bit_support
  )
    return false;

  // Used by both the SCSI and char interfaces
  TW_Passthru *passthru=NULL;
  char ioctl_buffer[TW_IOCTL_BUFFER_SIZE];

  // only used for SCSI device interface
  TW_Ioctl   *tw_ioctl=NULL;
  TW_Output *tw_output=NULL;

  // only used for 6000/7000/8000 char device interface
  TW_New_Ioctl *tw_ioctl_char=NULL;

  // only used for 9000 character device interface
  TW_Ioctl_Buf_Apache *tw_ioctl_apache=NULL;

  memset(ioctl_buffer, 0, TW_IOCTL_BUFFER_SIZE);

  // TODO: Handle controller differences by different classes
  if (m_escalade_type == AMCC_3WARE_9700_CHAR || m_escalade_type == AMCC_3WARE_9000_CHAR) {
    tw_ioctl_apache                               = (TW_Ioctl_Buf_Apache *)ioctl_buffer;
    tw_ioctl_apache->driver_command.control_code  = TW_IOCTL_FIRMWARE_PASS_THROUGH;
    tw_ioctl_apache->driver_command.buffer_length = 512; /* payload size */
    passthru                                      = (TW_Passthru *)&(tw_ioctl_apache->firmware_command.command.oldcommand);
  }
  else if (m_escalade_type==AMCC_3WARE_678K_CHAR) {
    tw_ioctl_char                                 = (TW_New_Ioctl *)ioctl_buffer;
    tw_ioctl_char->data_buffer_length             = 512;
    passthru                                      = (TW_Passthru *)&(tw_ioctl_char->firmware_command);
  }
  else if (m_escalade_type==AMCC_3WARE_678K) {
    tw_ioctl                                      = (TW_Ioctl *)ioctl_buffer;
    tw_ioctl->cdb[0]                              = TW_IOCTL;
    tw_ioctl->opcode                              = TW_ATA_PASSTHRU;
    tw_ioctl->input_length                        = 512; // correct even for non-data commands
    tw_ioctl->output_length                       = 512; // correct even for non-data commands
    tw_output                                     = (TW_Output *)tw_ioctl;
    passthru                                      = (TW_Passthru *)&(tw_ioctl->input_data);
  }
  else {
    return set_err(ENOSYS,
      "Unrecognized escalade_type %d in linux_3ware_command_interface(disk %d)\n"
      "Please contact " PACKAGE_BUGREPORT "\n", (int)m_escalade_type, m_disknum);
  }

  // Same for (almost) all commands - but some reset below
  passthru->byte0.opcode  = TW_OP_ATA_PASSTHRU;
  passthru->request_id    = 0xFF;
  passthru->unit          = m_disknum;
  passthru->status        = 0;
  passthru->flags         = 0x1;

  // Set registers
  {
    const ata_in_regs_48bit & r = in.in_regs;
    passthru->features     = r.features_16;
    passthru->sector_count = r.sector_count_16;
    passthru->sector_num   = r.lba_low_16;
    passthru->cylinder_lo  = r.lba_mid_16;
    passthru->cylinder_hi  = r.lba_high_16;
    passthru->drive_head   = r.device;
    passthru->command      = r.command;
  }

  // Is this a command that reads or returns 512 bytes?
  // passthru->param values are:
  // 0x0 - non data command without TFR write check,
  // 0x8 - non data command with TFR write check,
  // 0xD - data command that returns data to host from device
  // 0xF - data command that writes data from host to device
  // passthru->size values are 0x5 for non-data and 0x07 for data
  bool readdata = false;
  if (in.direction == ata_cmd_in::data_in) {
    readdata=true;
    passthru->byte0.sgloff = 0x5;
    passthru->size         = 0x7; // TODO: Other value for multi-sector ?
    passthru->param        = 0xD;
    // For 64-bit to work correctly, up the size of the command packet
    // in dwords by 1 to account for the 64-bit single sgl 'address'
    // field. Note that this doesn't agree with the typedefs but it's
    // right (agree with kernel driver behavior/typedefs).
    if ((m_escalade_type == AMCC_3WARE_9700_CHAR || m_escalade_type == AMCC_3WARE_9000_CHAR)
        && sizeof(long) == 8)
      passthru->size++;
  }
  else if (in.direction == ata_cmd_in::no_data) {
    // Non data command -- but doesn't use large sector
    // count register values.
    passthru->byte0.sgloff = 0x0;
    passthru->size         = 0x5;
    passthru->param        = 0x8;
    passthru->sector_count = 0x0;
  }
  else if (in.direction == ata_cmd_in::data_out) {
    if (m_escalade_type == AMCC_3WARE_9700_CHAR || m_escalade_type == AMCC_3WARE_9000_CHAR)
      memcpy(tw_ioctl_apache->data_buffer, in.buffer, in.size);
    else if (m_escalade_type == AMCC_3WARE_678K_CHAR)
      memcpy(tw_ioctl_char->data_buffer,   in.buffer, in.size);
    else {
      // COMMAND NOT SUPPORTED VIA SCSI IOCTL INTERFACE
      // memcpy(tw_output->output_data, data, 512);
      // printwarning(command); // TODO: Parameter no longer valid
      return set_err(ENOTSUP, "DATA OUT not supported for this 3ware controller type");
    }
    passthru->byte0.sgloff = 0x5;
    passthru->size         = 0x7;  // TODO: Other value for multi-sector ?
    passthru->param        = 0xF;  // PIO data write
    if ((m_escalade_type == AMCC_3WARE_9700_CHAR || m_escalade_type == AMCC_3WARE_9000_CHAR)
        && sizeof(long) == 8)
      passthru->size++;
  }
  else
    return set_err(EINVAL);

  // Now send the command down through an ioctl()
  int ioctlreturn;
  if (m_escalade_type == AMCC_3WARE_9700_CHAR || m_escalade_type == AMCC_3WARE_9000_CHAR)
    ioctlreturn=ioctl(get_fd(), TW_IOCTL_FIRMWARE_PASS_THROUGH, tw_ioctl_apache);
  else if (m_escalade_type==AMCC_3WARE_678K_CHAR)
    ioctlreturn=ioctl(get_fd(), TW_CMD_PACKET_WITH_DATA, tw_ioctl_char);
  else
    ioctlreturn=ioctl(get_fd(), SCSI_IOCTL_SEND_COMMAND, tw_ioctl);

  // Deal with the different error cases
  if (ioctlreturn) {
    if (AMCC_3WARE_678K==m_escalade_type
        && in.in_regs.command==ATA_SMART_CMD
        && (   in.in_regs.features == ATA_SMART_AUTO_OFFLINE
            || in.in_regs.features == ATA_SMART_AUTOSAVE    )
        && in.in_regs.lba_low) {
      // error here is probably a kernel driver whose version is too old
      // printwarning(command); // TODO: Parameter no longer valid
      return set_err(ENOTSUP, "Probably kernel driver too old");
    }
    return set_err(EIO);
  }

  // The passthru structure is valid after return from an ioctl if:
  // - we are using the character interface OR
  // - we are using the SCSI interface and this is a NON-READ-DATA command
  // For SCSI interface, note that we set passthru to a different
  // value after ioctl().
  if (AMCC_3WARE_678K==m_escalade_type) {
    if (readdata)
      passthru=NULL;
    else
      passthru=(TW_Passthru *)&(tw_output->output_data);
  }

  // See if the ATA command failed.  Now that we have returned from
  // the ioctl() call, if passthru is valid, then:
  // - passthru->status contains the 3ware controller STATUS
  // - passthru->command contains the ATA STATUS register
  // - passthru->features contains the ATA ERROR register
  //
  // Check bits 0 (error bit) and 5 (device fault) of the ATA STATUS
  // If bit 0 (error bit) is set, then ATA ERROR register is valid.
  // While we *might* decode the ATA ERROR register, at the moment it
  // doesn't make much sense: we don't care in detail why the error
  // happened.

  if (passthru && (passthru->status || (passthru->command & 0x21))) {
    return set_err(EIO);
  }

  // If this is a read data command, copy data to output buffer
  if (readdata) {
    if (m_escalade_type == AMCC_3WARE_9700_CHAR || m_escalade_type == AMCC_3WARE_9000_CHAR)
      memcpy(in.buffer, tw_ioctl_apache->data_buffer, in.size);
    else if (m_escalade_type==AMCC_3WARE_678K_CHAR)
      memcpy(in.buffer, tw_ioctl_char->data_buffer, in.size);
    else
      memcpy(in.buffer, tw_output->output_data, in.size);
  }

  // Return register values
  if (passthru) {
    ata_out_regs_48bit & r = out.out_regs;
    r.error           = passthru->features;
    r.sector_count_16 = passthru->sector_count;
    r.lba_low_16      = passthru->sector_num;
    r.lba_mid_16      = passthru->cylinder_lo;
    r.lba_high_16     = passthru->cylinder_hi;
    r.device          = passthru->drive_head;
    r.status          = passthru->command;
  }

  // look for nonexistent devices/ports
  if (   in.in_regs.command == ATA_IDENTIFY_DEVICE
      && !nonempty(in.buffer, in.size)) {
    return set_err(ENODEV, "No drive on port %d", m_disknum);
  }

  return true;
}

/////////////////////////////////////////////////////////////////////////////
/// Areca RAID support

///////////////////////////////////////////////////////////////////
// SATA(ATA) device behind Areca RAID Controller
class linux_areca_ata_device
: public /*implements*/ areca_ata_device,
  public /*extends*/ linux_smart_device
{
public:
  linux_areca_ata_device(smart_interface * intf, const char * dev_name, int disknum, int encnum = 1);
  virtual smart_device * autodetect_open();
  virtual bool arcmsr_lock();
  virtual bool arcmsr_unlock();
  virtual int arcmsr_do_scsi_io(struct scsi_cmnd_io * iop);
};

///////////////////////////////////////////////////////////////////
// SAS(SCSI) device behind Areca RAID Controller
class linux_areca_scsi_device
: public /*implements*/ areca_scsi_device,
  public /*extends*/ linux_smart_device
{
public:
  linux_areca_scsi_device(smart_interface * intf, const char * dev_name, int disknum, int encnum = 1);
  virtual smart_device * autodetect_open();
  virtual bool arcmsr_lock();
  virtual bool arcmsr_unlock();
  virtual int arcmsr_do_scsi_io(struct scsi_cmnd_io * iop);
};

// Looks in /proc/scsi to suggest correct areca devices
static int find_areca_in_proc()
{
    const char* proc_format_string="host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n";

    // check data formwat
    FILE *fp=fopen("/proc/scsi/sg/device_hdr", "r");
    if (!fp) {
        pout("Unable to open /proc/scsi/sg/device_hdr for reading\n");
        return 1;
     }

     // get line, compare to format
     char linebuf[256];
     linebuf[255]='\0';
     char *out = fgets(linebuf, 256, fp);
     fclose(fp);
     if (!out) {
         pout("Unable to read contents of /proc/scsi/sg/device_hdr\n");
         return 2;
     }

     if (strcmp(linebuf, proc_format_string)) {
     	// wrong format!
	// Fix this by comparing only tokens not white space!!
	pout("Unexpected format %s in /proc/scsi/sg/device_hdr\n", proc_format_string);
	return 3;
     }

    // Format is understood, now search for correct device
    fp=fopen("/proc/scsi/sg/devices", "r");
    if (!fp) return 1;
    int host, chan, id, lun, type, opens, qdepth, busy, online;
    int dev=-1;
    int found=0;
    // search all lines of /proc/scsi/sg/devices
    while (9 == fscanf(fp, "%d %d %d %d %d %d %d %d %d", &host, &chan, &id, &lun, &type, &opens, &qdepth, &busy, &online)) {
        dev++;
	if (id == 16 && type == 3) {
	   // devices with id=16 and type=3 might be Areca controllers
	   pout("Device /dev/sg%d appears to be an Areca controller.\n", dev);
           found++;
        }
    }
    fclose(fp);
    return 0;
}

// Areca RAID Controller(SATA Disk)
linux_areca_ata_device::linux_areca_ata_device(smart_interface * intf, const char * dev_name, int disknum, int encnum)
: smart_device(intf, dev_name, "areca", "areca"),
  linux_smart_device(O_RDWR | O_EXCL | O_NONBLOCK)
{
  set_disknum(disknum);
  set_encnum(encnum);
  set_info().info_name = strprintf("%s [areca_disk#%02d_enc#%02d]", dev_name, disknum, encnum);
}

smart_device * linux_areca_ata_device::autodetect_open()
{
  int is_ata = 1;

  // autodetect device type
  is_ata = arcmsr_get_dev_type();
  if(is_ata < 0)
  {
    set_err(EIO);
    return this;
  }

  if(is_ata == 1)
  {
    // SATA device
    return this;
  }

  // SAS device
  smart_device_auto_ptr newdev(new linux_areca_scsi_device(smi(), get_dev_name(), get_disknum(), get_encnum()));
  close();
  delete this;
  newdev->open();	// TODO: Can possibly pass open fd

  return newdev.release();
}

int linux_areca_ata_device::arcmsr_do_scsi_io(struct scsi_cmnd_io * iop)
{
  int ioctlreturn = 0;

  if(!is_open()) {
      if(!open()){
          find_areca_in_proc();
      }
  }

  ioctlreturn = do_normal_scsi_cmnd_io(get_fd(), iop, scsi_debugmode);
  if ( ioctlreturn || iop->scsi_status )
  {
    // errors found
    return -1;
  }

  return ioctlreturn;
}

bool linux_areca_ata_device::arcmsr_lock()
{
  return true;
}

bool linux_areca_ata_device::arcmsr_unlock()
{
  return true;
}

// Areca RAID Controller(SAS Device)
linux_areca_scsi_device::linux_areca_scsi_device(smart_interface * intf, const char * dev_name, int disknum, int encnum)
: smart_device(intf, dev_name, "areca", "areca"),
  linux_smart_device(O_RDWR | O_EXCL | O_NONBLOCK)
{
  set_disknum(disknum);
  set_encnum(encnum);
  set_info().info_name = strprintf("%s [areca_disk#%02d_enc#%02d]", dev_name, disknum, encnum);
}

smart_device * linux_areca_scsi_device::autodetect_open()
{
  return this;
}

int linux_areca_scsi_device::arcmsr_do_scsi_io(struct scsi_cmnd_io * iop)
{
  int ioctlreturn = 0;

  if(!is_open()) {
      if(!open()){
          find_areca_in_proc();
      }
  }

  ioctlreturn = do_normal_scsi_cmnd_io(get_fd(), iop, scsi_debugmode);
  if ( ioctlreturn || iop->scsi_status )
  {
    // errors found
    return -1;
  }

  return ioctlreturn;
}

bool linux_areca_scsi_device::arcmsr_lock()
{
  return true;
}

bool linux_areca_scsi_device::arcmsr_unlock()
{
  return true;
}

/////////////////////////////////////////////////////////////////////////////
/// Marvell support

class linux_marvell_device
: public /*implements*/ ata_device_with_command_set,
  public /*extends*/ linux_smart_device
{
public:
  linux_marvell_device(smart_interface * intf, const char * dev_name, const char * req_type);

protected:
  virtual int ata_command_interface(smart_command_set command, int select, char * data);
};

linux_marvell_device::linux_marvell_device(smart_interface * intf,
  const char * dev_name, const char * req_type)
: smart_device(intf, dev_name, "marvell", req_type),
  linux_smart_device(O_RDONLY | O_NONBLOCK)
{
}

int linux_marvell_device::ata_command_interface(smart_command_set command, int select, char * data)
{
  typedef struct {
    int  inlen;
    int  outlen;
    char cmd[540];
  } mvsata_scsi_cmd;

  int copydata = 0;
  mvsata_scsi_cmd  smart_command;
  unsigned char *buff = (unsigned char *)&smart_command.cmd[6];
  // See struct hd_drive_cmd_hdr in hdreg.h
  // buff[0]: ATA COMMAND CODE REGISTER
  // buff[1]: ATA SECTOR NUMBER REGISTER
  // buff[2]: ATA FEATURES REGISTER
  // buff[3]: ATA SECTOR COUNT REGISTER

  // clear out buff.  Large enough for HDIO_DRIVE_CMD (4+512 bytes)
  memset(&smart_command, 0, sizeof(smart_command));
  smart_command.inlen = 540;
  smart_command.outlen = 540;
  smart_command.cmd[0] = 0xC;  //Vendor-specific code
  smart_command.cmd[4] = 6;     //command length

  buff[0] = ATA_SMART_CMD;
  switch (command){
  case CHECK_POWER_MODE:
    buff[0]=ATA_CHECK_POWER_MODE;
    break;
  case READ_VALUES:
    buff[2]=ATA_SMART_READ_VALUES;
    copydata=buff[3]=1;
    break;
  case READ_THRESHOLDS:
    buff[2]=ATA_SMART_READ_THRESHOLDS;
    copydata=buff[1]=buff[3]=1;
    break;
  case READ_LOG:
    buff[2]=ATA_SMART_READ_LOG_SECTOR;
    buff[1]=select;
    copydata=buff[3]=1;
    break;
  case IDENTIFY:
    buff[0]=ATA_IDENTIFY_DEVICE;
    copydata=buff[3]=1;
    break;
  case PIDENTIFY:
    buff[0]=ATA_IDENTIFY_PACKET_DEVICE;
    copydata=buff[3]=1;
    break;
  case ENABLE:
    buff[2]=ATA_SMART_ENABLE;
    buff[1]=1;
    break;
  case DISABLE:
    buff[2]=ATA_SMART_DISABLE;
    buff[1]=1;
    break;
  case STATUS:
  case STATUS_CHECK:
    // this command only says if SMART is working.  It could be
    // replaced with STATUS_CHECK below.
    buff[2] = ATA_SMART_STATUS;
    break;
  case AUTO_OFFLINE:
    buff[2]=ATA_SMART_AUTO_OFFLINE;
    buff[3]=select;   // YET NOTE - THIS IS A NON-DATA COMMAND!!
    break;
  case AUTOSAVE:
    buff[2]=ATA_SMART_AUTOSAVE;
    buff[3]=select;   // YET NOTE - THIS IS A NON-DATA COMMAND!!
    break;
  case IMMEDIATE_OFFLINE:
    buff[2]=ATA_SMART_IMMEDIATE_OFFLINE;
    buff[1]=select;
    break;
  default:
    pout("Unrecognized command %d in mvsata_os_specific_handler()\n", command);
    EXIT(1);
    break;
  }
  // There are two different types of ioctls().  The HDIO_DRIVE_TASK
  // one is this:
  // We are now doing the HDIO_DRIVE_CMD type ioctl.
  if (ioctl(get_fd(), SCSI_IOCTL_SEND_COMMAND, (void *)&smart_command))
      return -1;

  if (command==CHECK_POWER_MODE) {
    // LEON -- CHECK THIS PLEASE.  THIS SHOULD BE THE SECTOR COUNT
    // REGISTER, AND IT MIGHT BE buff[2] NOT buff[3].  Bruce
    data[0]=buff[3];
    return 0;
  }

  // Always succeed on a SMART status, as a disk that failed returned
  // buff[4]=0xF4, buff[5]=0x2C, i.e. "Bad SMART status" (see below).
  if (command == STATUS)
    return 0;
  //Data returned is starting from 0 offset
  if (command == STATUS_CHECK)
  {
    // Cyl low and Cyl high unchanged means "Good SMART status"
    if (buff[4] == 0x4F && buff[5] == 0xC2)
      return 0;
    // These values mean "Bad SMART status"
    if (buff[4] == 0xF4 && buff[5] == 0x2C)
      return 1;
    // We haven't gotten output that makes sense; print out some debugging info
    syserror("Error SMART Status command failed");
    pout("Please get assistance from %s\n",PACKAGE_BUGREPORT);
    pout("Register values returned from SMART Status command are:\n");
    pout("CMD =0x%02x\n",(int)buff[0]);
    pout("FR =0x%02x\n",(int)buff[1]);
    pout("NS =0x%02x\n",(int)buff[2]);
    pout("SC =0x%02x\n",(int)buff[3]);
    pout("CL =0x%02x\n",(int)buff[4]);
    pout("CH =0x%02x\n",(int)buff[5]);
    pout("SEL=0x%02x\n",(int)buff[6]);
    return -1;
  }

  if (copydata)
    memcpy(data, buff, 512);
  return 0;
}

/////////////////////////////////////////////////////////////////////////////
/// Highpoint RAID support

class linux_highpoint_device
: public /*implements*/ ata_device_with_command_set,
  public /*extends*/ linux_smart_device
{
public:
  linux_highpoint_device(smart_interface * intf, const char * dev_name,
    unsigned char controller, unsigned char channel, unsigned char port);

protected:
  virtual int ata_command_interface(smart_command_set command, int select, char * data);

private:
  unsigned char m_hpt_data[3]; ///< controller/channel/port
};

linux_highpoint_device::linux_highpoint_device(smart_interface * intf, const char * dev_name,
  unsigned char controller, unsigned char channel, unsigned char port)
: smart_device(intf, dev_name, "hpt", "hpt"),
  linux_smart_device(O_RDONLY | O_NONBLOCK)
{
  m_hpt_data[0] = controller; m_hpt_data[1] = channel; m_hpt_data[2] = port;
  set_info().info_name = strprintf("%s [hpt_disk_%u/%u/%u]", dev_name, m_hpt_data[0], m_hpt_data[1], m_hpt_data[2]);
}

// this implementation is derived from ata_command_interface with a header
// packing for highpoint linux driver ioctl interface
//
// ioctl(fd,HPTIO_CTL,buff)
//          ^^^^^^^^^
//
// structure of hpt_buff
// +----+----+----+----+--------------------.....---------------------+
// | 1  | 2  | 3  | 4  | 5                                            |
// +----+----+----+----+--------------------.....---------------------+
//
// 1: The target controller                     [ int    ( 4 Bytes ) ]
// 2: The channel of the target controllee      [ int    ( 4 Bytes ) ]
// 3: HDIO_ ioctl call                          [ int    ( 4 Bytes ) ]
//    available from ${LINUX_KERNEL_SOURCE}/Documentation/ioctl/hdio
// 4: the pmport that disk attached,            [ int    ( 4 Bytes ) ]
//    if no pmport device, set to 1 or leave blank
// 5: data                                      [ void * ( var leangth ) ]
//
#define STRANGE_BUFFER_LENGTH (4+512*0xf8)

int linux_highpoint_device::ata_command_interface(smart_command_set command, int select, char * data)
{
  unsigned char hpt_buff[4*sizeof(int) + STRANGE_BUFFER_LENGTH];
  unsigned int *hpt = (unsigned int *)hpt_buff;
  unsigned char *buff = &hpt_buff[4*sizeof(int)];
  int copydata = 0;
  const int HDIO_DRIVE_CMD_OFFSET = 4;

  memset(hpt_buff, 0, 4*sizeof(int) + STRANGE_BUFFER_LENGTH);
  hpt[0] = m_hpt_data[0]; // controller id
  hpt[1] = m_hpt_data[1]; // channel number
  hpt[3] = m_hpt_data[2]; // pmport number

  buff[0]=ATA_SMART_CMD;
  switch (command){
  case CHECK_POWER_MODE:
    buff[0]=ATA_CHECK_POWER_MODE;
    copydata=1;
    break;
  case READ_VALUES:
    buff[2]=ATA_SMART_READ_VALUES;
    buff[3]=1;
    copydata=512;
    break;
  case READ_THRESHOLDS:
    buff[2]=ATA_SMART_READ_THRESHOLDS;
    buff[1]=buff[3]=1;
    copydata=512;
    break;
  case READ_LOG:
    buff[2]=ATA_SMART_READ_LOG_SECTOR;
    buff[1]=select;
    buff[3]=1;
    copydata=512;
    break;
  case WRITE_LOG:
    break;
  case IDENTIFY:
    buff[0]=ATA_IDENTIFY_DEVICE;
    buff[3]=1;
    copydata=512;
    break;
  case PIDENTIFY:
    buff[0]=ATA_IDENTIFY_PACKET_DEVICE;
    buff[3]=1;
    copydata=512;
    break;
  case ENABLE:
    buff[2]=ATA_SMART_ENABLE;
    buff[1]=1;
    break;
  case DISABLE:
    buff[2]=ATA_SMART_DISABLE;
    buff[1]=1;
    break;
  case STATUS:
    buff[2]=ATA_SMART_STATUS;
    break;
  case AUTO_OFFLINE:
    buff[2]=ATA_SMART_AUTO_OFFLINE;
    buff[3]=select;
    break;
  case AUTOSAVE:
    buff[2]=ATA_SMART_AUTOSAVE;
    buff[3]=select;
    break;
  case IMMEDIATE_OFFLINE:
    buff[2]=ATA_SMART_IMMEDIATE_OFFLINE;
    buff[1]=select;
    break;
  case STATUS_CHECK:
    buff[1]=ATA_SMART_STATUS;
    break;
  default:
    pout("Unrecognized command %d in linux_highpoint_command_interface()\n"
         "Please contact " PACKAGE_BUGREPORT "\n", command);
    errno=ENOSYS;
    return -1;
  }

  if (command==WRITE_LOG) {
    unsigned char task[4*sizeof(int)+sizeof(ide_task_request_t)+512];
    unsigned int *hpt_tf = (unsigned int *)task;
    ide_task_request_t *reqtask = (ide_task_request_t *)(&task[4*sizeof(int)]);
    task_struct_t *taskfile = (task_struct_t *)reqtask->io_ports;
    int retval;

    memset(task, 0, sizeof(task));

    hpt_tf[0] = m_hpt_data[0]; // controller id
    hpt_tf[1] = m_hpt_data[1]; // channel number
    hpt_tf[3] = m_hpt_data[2]; // pmport number
    hpt_tf[2] = HDIO_DRIVE_TASKFILE; // real hd ioctl

    taskfile->data           = 0;
    taskfile->feature        = ATA_SMART_WRITE_LOG_SECTOR;
    taskfile->sector_count   = 1;
    taskfile->sector_number  = select;
    taskfile->low_cylinder   = 0x4f;
    taskfile->high_cylinder  = 0xc2;
    taskfile->device_head    = 0;
    taskfile->command        = ATA_SMART_CMD;

    reqtask->data_phase      = TASKFILE_OUT;
    reqtask->req_cmd         = IDE_DRIVE_TASK_OUT;
    reqtask->out_size        = 512;
    reqtask->in_size         = 0;

    memcpy(task+sizeof(ide_task_request_t)+4*sizeof(int), data, 512);

    if ((retval=ioctl(get_fd(), HPTIO_CTL, task))) {
      if (retval==-EINVAL)
        pout("Kernel lacks HDIO_DRIVE_TASKFILE support; compile kernel with CONFIG_IDE_TASKFILE_IO set\n");
      return -1;
    }
    return 0;
  }

  if (command==STATUS_CHECK){
    int retval;
    unsigned const char normal_lo=0x4f, normal_hi=0xc2;
    unsigned const char failed_lo=0xf4, failed_hi=0x2c;
    buff[4]=normal_lo;
    buff[5]=normal_hi;

    hpt[2] = HDIO_DRIVE_TASK;

    if ((retval=ioctl(get_fd(), HPTIO_CTL, hpt_buff))) {
      if (retval==-EINVAL) {
        pout("Error SMART Status command via HDIO_DRIVE_TASK failed");
        pout("Rebuild older linux 2.2 kernels with HDIO_DRIVE_TASK support added\n");
      }
      else
        syserror("Error SMART Status command failed");
      return -1;
    }

    if (buff[4]==normal_lo && buff[5]==normal_hi)
      return 0;

    if (buff[4]==failed_lo && buff[5]==failed_hi)
      return 1;

    syserror("Error SMART Status command failed");
    pout("Please get assistance from " PACKAGE_HOMEPAGE "\n");
    pout("Register values returned from SMART Status command are:\n");
    pout("CMD=0x%02x\n",(int)buff[0]);
    pout("FR =0x%02x\n",(int)buff[1]);
    pout("NS =0x%02x\n",(int)buff[2]);
    pout("SC =0x%02x\n",(int)buff[3]);
    pout("CL =0x%02x\n",(int)buff[4]);
    pout("CH =0x%02x\n",(int)buff[5]);
    pout("SEL=0x%02x\n",(int)buff[6]);
    return -1;
  }

#if 1
  if (command==IDENTIFY || command==PIDENTIFY) {
    unsigned char deviceid[4*sizeof(int)+512*sizeof(char)];
    unsigned int *hpt_id = (unsigned int *)deviceid;

    hpt_id[0] = m_hpt_data[0]; // controller id
    hpt_id[1] = m_hpt_data[1]; // channel number
    hpt_id[3] = m_hpt_data[2]; // pmport number

    hpt_id[2] = HDIO_GET_IDENTITY;
    if (!ioctl(get_fd(), HPTIO_CTL, deviceid) && (deviceid[4*sizeof(int)] & 0x8000))
      buff[0]=(command==IDENTIFY)?ATA_IDENTIFY_PACKET_DEVICE:ATA_IDENTIFY_DEVICE;
  }
#endif

  hpt[2] = HDIO_DRIVE_CMD;
  if ((ioctl(get_fd(), HPTIO_CTL, hpt_buff)))
    return -1;

  if (command==CHECK_POWER_MODE)
    buff[HDIO_DRIVE_CMD_OFFSET]=buff[2];

  if (copydata)
    memcpy(data, buff+HDIO_DRIVE_CMD_OFFSET, copydata);

  return 0;
}

#if 0 // TODO: Migrate from 'smart_command_set' to 'ata_in_regs' OR remove the function
// Utility function for printing warnings
void printwarning(smart_command_set command){
  static int printed[4]={0,0,0,0};
  const char* message=
    "can not be passed through the 3ware 3w-xxxx driver.  This can be fixed by\n"
    "applying a simple 3w-xxxx driver patch that can be found here:\n"
    PACKAGE_HOMEPAGE "\n"
    "Alternatively, upgrade your 3w-xxxx driver to version 1.02.00.037 or greater.\n\n";

  if (command==AUTO_OFFLINE && !printed[0]) {
    printed[0]=1;
    pout("The SMART AUTO-OFFLINE ENABLE command (smartmontools -o on option/Directive)\n%s", message);
  }
  else if (command==AUTOSAVE && !printed[1]) {
    printed[1]=1;
    pout("The SMART AUTOSAVE ENABLE command (smartmontools -S on option/Directive)\n%s", message);
  }
  else if (command==STATUS_CHECK && !printed[2]) {
    printed[2]=1;
    pout("The SMART RETURN STATUS return value (smartmontools -H option/Directive)\n%s", message);
  }
  else if (command==WRITE_LOG && !printed[3])  {
    printed[3]=1;
    pout("The SMART WRITE LOG command (smartmontools -t selective) only supported via char /dev/tw[ae] interface\n");
  }

  return;
}
#endif

/////////////////////////////////////////////////////////////////////////////
/// SCSI open with autodetection support

smart_device * linux_scsi_device::autodetect_open()
{
  // Open device
  if (!open())
    return this;

  // No Autodetection if device type was specified by user
  bool sat_only = false;
  if (*get_req_type()) {
    // Detect SAT if device object was created by scan_smart_devices().
    if (!(m_scanning && !strcmp(get_req_type(), "sat")))
      return this;
    sat_only = true;
  }

  // The code below is based on smartd.cpp:SCSIFilterKnown()

  // Get INQUIRY
  unsigned char req_buff[64] = {0, };
  int req_len = 36;
  if (scsiStdInquiry(this, req_buff, req_len)) {
    // Marvell controllers fail on a 36 bytes StdInquiry, but 64 suffices
    // watch this spot ... other devices could lock up here
    req_len = 64;
    if (scsiStdInquiry(this, req_buff, req_len)) {
      // device doesn't like INQUIRY commands
      close();
      set_err(EIO, "INQUIRY failed");
      return this;
    }
  }

  int avail_len = req_buff[4] + 5;
  int len = (avail_len < req_len ? avail_len : req_len);
  if (len < 36) {
    if (sat_only) {
      close();
      set_err(EIO, "INQUIRY too short for SAT");
    }
    return this;
  }

  // Use INQUIRY to detect type
  if (!sat_only) {

    // 3ware ?
    if (!memcmp(req_buff + 8, "3ware", 5) || !memcmp(req_buff + 8, "AMCC", 4)) {
      close();
      set_err(EINVAL, "AMCC/3ware controller, please try adding '-d 3ware,N',\n"
                      "you may need to replace %s with /dev/twlN, /dev/twaN or /dev/tweN", get_dev_name());
      return this;
    }

    // DELL?
    if (!memcmp(req_buff + 8, "DELL    PERC", 12) || !memcmp(req_buff + 8, "MegaRAID", 8)
        || !memcmp(req_buff + 16, "PERC H700", 9) || !memcmp(req_buff + 8, "LSI\0",4)
    ) {
      close();
      set_err(EINVAL, "DELL or MegaRaid controller, please try adding '-d megaraid,N'");
      return this;
    }

    // Marvell ?
    if (len >= 42 && !memcmp(req_buff + 36, "MVSATA", 6)) {
      //pout("Device %s: using '-d marvell' for ATA disk with Marvell driver\n", get_dev_name());
      close();
      smart_device_auto_ptr newdev(
        new linux_marvell_device(smi(), get_dev_name(), get_req_type())
      );
      newdev->open(); // TODO: Can possibly pass open fd
      delete this;
      return newdev.release();
    }
  }

  // SAT or USB ?
  {
    smart_device * newdev = smi()->autodetect_sat_device(this, req_buff, len);
    if (newdev)
      // NOTE: 'this' is now owned by '*newdev'
      return newdev;
  }

  // Nothing special found

  if (sat_only) {
    close();
    set_err(EIO, "Not a SAT device");
  }
  return this;
}

//////////////////////////////////////////////////////////////////////
// USB bridge ID detection

// Read USB ID from /sys file
static bool read_id(const std::string & path, unsigned short & id)
{
  FILE * f = fopen(path.c_str(), "r");
  if (!f)
    return false;
  int n = -1;
  bool ok = (fscanf(f, "%hx%n", &id, &n) == 1 && n == 4);
  fclose(f);
  return ok;
}

// Get USB bridge ID for "sdX"
static bool get_usb_id(const char * name, unsigned short & vendor_id,
                       unsigned short & product_id, unsigned short & version)
{
  // Only "sdX" supported
  if (!(!strncmp(name, "sd", 2) && !strchr(name, '/')))
    return false;

  // Start search at dir referenced by symlink "/sys/block/sdX/device"
  // -> "/sys/devices/.../usb*/.../host*/target*/..."
  std::string dir = strprintf("/sys/block/%s/device", name);

  // Stop search at "/sys/devices"
  struct stat st;
  if (stat("/sys/devices", &st))
    return false;
  ino_t stop_ino = st.st_ino;

  // Search in parent directories until "idVendor" is found,
  // fail if "/sys/devices" reached or too many iterations
  int cnt = 0;
  do {
    dir += "/..";
    if (!(++cnt < 10 && !stat(dir.c_str(), &st) && st.st_ino != stop_ino))
      return false;
  } while (access((dir + "/idVendor").c_str(), 0));

  // Read IDs
  if (!(   read_id(dir + "/idVendor", vendor_id)
        && read_id(dir + "/idProduct", product_id)
        && read_id(dir + "/bcdDevice", version)   ))
    return false;

  if (scsi_debugmode > 1)
    pout("USB ID = 0x%04x:0x%04x (0x%03x)\n", vendor_id, product_id, version);
  return true;
}

//////////////////////////////////////////////////////////////////////
/// Linux interface

class linux_smart_interface
: public /*implements*/ smart_interface
{
public:
  virtual std::string get_os_version_str();

  virtual std::string get_app_examples(const char * appname);

  virtual bool scan_smart_devices(smart_device_list & devlist, const char * type,
    const char * pattern = 0);

protected:
  virtual ata_device * get_ata_device(const char * name, const char * type);

  virtual scsi_device * get_scsi_device(const char * name, const char * type);

  virtual smart_device * autodetect_smart_device(const char * name);

  virtual smart_device * get_custom_smart_device(const char * name, const char * type);

  virtual std::string get_valid_custom_dev_types_str();

private:
  bool get_dev_list(smart_device_list & devlist, const char * pattern,
    bool scan_ata, bool scan_scsi, const char * req_type, bool autodetect);
  bool get_dev_megasas(smart_device_list & devlist);
  smart_device * missing_option(const char * opt);
  int megasas_dcmd_cmd(int bus_no, uint32_t opcode, void *buf,
    size_t bufsize, uint8_t *mbox, size_t mboxlen, uint8_t *statusp);
  int megasas_pd_add_list(int bus_no, smart_device_list & devlist);
};

std::string linux_smart_interface::get_os_version_str()
{
  struct utsname u;
  if (!uname(&u))
    return strprintf("%s-linux-%s", u.machine, u.release);
  else
    return SMARTMONTOOLS_BUILD_HOST;
}

std::string linux_smart_interface::get_app_examples(const char * appname)
{
  if (!strcmp(appname, "smartctl"))
    return smartctl_examples;
  return "";
}

// we are going to take advantage of the fact that Linux's devfs will only
// have device entries for devices that exist.  So if we get the equivalent of
// ls /dev/hd[a-t], we have all the ATA devices on the system
bool linux_smart_interface::get_dev_list(smart_device_list & devlist,
  const char * pattern, bool scan_ata, bool scan_scsi,
  const char * req_type, bool autodetect)
{
  // Use glob to look for any directory entries matching the pattern
  glob_t globbuf;
  memset(&globbuf, 0, sizeof(globbuf));
  int retglob = glob(pattern, GLOB_ERR, NULL, &globbuf);
  if (retglob) {
    //  glob failed: free memory and return
    globfree(&globbuf);

    if (retglob==GLOB_NOMATCH){
      pout("glob(3) found no matches for pattern %s\n", pattern);
      return true;
    }

    if (retglob==GLOB_NOSPACE)
      set_err(ENOMEM, "glob(3) ran out of memory matching pattern %s", pattern);
#ifdef GLOB_ABORTED // missing in old versions of glob.h
    else if (retglob==GLOB_ABORTED)
      set_err(EINVAL, "glob(3) aborted matching pattern %s", pattern);
#endif
    else
      set_err(EINVAL, "Unexplained error in glob(3) of pattern %s", pattern);

    return false;
  }

  // did we find too many paths?
  const int max_pathc = 32;
  int n = (int)globbuf.gl_pathc;
  if (n > max_pathc) {
    pout("glob(3) found %d > MAX=%d devices matching pattern %s: ignoring %d paths\n",
         n, max_pathc, pattern, n - max_pathc);
    n = max_pathc;
  }

  // now step through the list returned by glob.  If not a link, copy
  // to list.  If it is a link, evaluate it and see if the path ends
  // in "disc".
  for (int i = 0; i < n; i++){
    // see if path is a link
    char linkbuf[1024];
    int retlink = readlink(globbuf.gl_pathv[i], linkbuf, sizeof(linkbuf)-1);

    char tmpname[1024]={0};
    const char * name = 0;
    bool is_scsi = scan_scsi;
    // if not a link (or a strange link), keep it
    if (retlink<=0 || retlink>1023)
      name = globbuf.gl_pathv[i];
    else {
      // or if it's a link that points to a disc, follow it
      linkbuf[retlink] = 0;
      const char *p;
      if ((p=strrchr(linkbuf, '/')) && !strcmp(p+1, "disc"))
        // This is the branch of the code that gets followed if we are
        // using devfs WITH traditional compatibility links. In this
        // case, we add the traditional device name to the list that
        // is returned.
        name = globbuf.gl_pathv[i];
      else {
        // This is the branch of the code that gets followed if we are
        // using devfs WITHOUT traditional compatibility links.  In
        // this case, we check that the link to the directory is of
        // the correct type, and then append "disc" to it.
        bool match_ata  = strstr(linkbuf, "ide");
        bool match_scsi = strstr(linkbuf, "scsi");
        if (((match_ata && scan_ata) || (match_scsi && scan_scsi)) && !(match_ata && match_scsi)) {
          is_scsi = match_scsi;
          snprintf(tmpname, sizeof(tmpname), "%s/disc", globbuf.gl_pathv[i]);
          name = tmpname;
        }
      }
    }

    if (name) {
      // Found a name, add device to list.
      smart_device * dev;
      if (autodetect)
        dev = autodetect_smart_device(name);
      else if (is_scsi)
        dev = new linux_scsi_device(this, name, req_type, true /*scanning*/);
      else
        dev = new linux_ata_device(this, name, req_type);
      if (dev) // autodetect_smart_device() may return nullptr.
        devlist.push_back(dev);
    }
  }

  // free memory
  globfree(&globbuf);
  return true;
}

// getting devices from LSI SAS MegaRaid, if available
bool linux_smart_interface::get_dev_megasas(smart_device_list & devlist)
{
  /* Scanning of disks on MegaRaid device */
  /* Perform mknod of device ioctl node */
  int   mjr, n1;
  char line[128];
  bool scan_megasas = false;
  FILE * fp = fopen("/proc/devices", "r");
  while (fgets(line, sizeof(line), fp) != NULL) {
    n1=0;
    if (sscanf(line, "%d megaraid_sas_ioctl%n", &mjr, &n1) == 1 && n1 == 22) {
      scan_megasas = true;
      n1=mknod("/dev/megaraid_sas_ioctl_node", S_IFCHR, makedev(mjr, 0));
      if(scsi_debugmode > 0)
        pout("Creating /dev/megaraid_sas_ioctl_node = %d\n", n1 >= 0 ? 0 : errno);
      if (n1 >= 0 || errno == EEXIST)
        break;
    }
  }
  fclose(fp);

  if(!scan_megasas)
    return false;

  // getting bus numbers with megasas devices
  struct dirent *ep;
  unsigned int host_no = 0;
  char sysfsdir[256];

  /* we are using sysfs to get list of all scsi hosts */
  DIR * dp = opendir ("/sys/class/scsi_host/");
  if (dp != NULL)
  {
    while ((ep = readdir (dp)) != NULL) {
      if (!sscanf(ep->d_name, "host%d", &host_no)) 
        continue;
      /* proc_name should be megaraid_sas */
      snprintf(sysfsdir, sizeof(sysfsdir) - 1,
        "/sys/class/scsi_host/host%d/proc_name", host_no);
      if((fp = fopen(sysfsdir, "r")) == NULL)
        continue;
      if(fgets(line, sizeof(line), fp) != NULL && !strncmp(line,"megaraid_sas",12)) {
        megasas_pd_add_list(host_no, devlist);
      }
      fclose(fp);
    }
    (void) closedir (dp);
  } else { /* sysfs not mounted ? */
    for(unsigned i = 0; i <=16; i++) // trying to add devices on first 16 buses
      megasas_pd_add_list(i, devlist);
  }
  return true;
}

bool linux_smart_interface::scan_smart_devices(smart_device_list & devlist,
  const char * type, const char * pattern /*= 0*/)
{
  if (pattern) {
    set_err(EINVAL, "DEVICESCAN with pattern not implemented yet");
    return false;
  }

  if (!type)
    type = "";

  bool scan_ata  = (!*type || !strcmp(type, "ata" ));
  // "sat" detection will be later handled in linux_scsi_device::autodetect_open()
  bool scan_scsi = (!*type || !strcmp(type, "scsi") || !strcmp(type, "sat"));
  if (!(scan_ata || scan_scsi))
    return true;

  if (scan_ata)
    get_dev_list(devlist, "/dev/hd[a-t]", true, false, type, false);
  if (scan_scsi) {
    bool autodetect = !*type; // Try USB autodetection if no type specifed
    get_dev_list(devlist, "/dev/sd[a-z]", false, true, type, autodetect);
    // Support up to 104 devices
    get_dev_list(devlist, "/dev/sd[a-c][a-z]", false, true, type, autodetect);
    // get device list from the megaraid device
    get_dev_megasas(devlist);
  }

  // if we found traditional links, we are done
  if (devlist.size() > 0)
    return true;

  // else look for devfs entries without traditional links
  // TODO: Add udev support
  return get_dev_list(devlist, "/dev/discs/disc*", scan_ata, scan_scsi, type, false);
}

ata_device * linux_smart_interface::get_ata_device(const char * name, const char * type)
{
  return new linux_ata_device(this, name, type);
}

scsi_device * linux_smart_interface::get_scsi_device(const char * name, const char * type)
{
  return new linux_scsi_device(this, name, type);
}

smart_device * linux_smart_interface::missing_option(const char * opt)
{
  set_err(EINVAL, "requires option '%s'", opt);
  return 0;
}

int
linux_smart_interface::megasas_dcmd_cmd(int bus_no, uint32_t opcode, void *buf,
  size_t bufsize, uint8_t *mbox, size_t mboxlen, uint8_t *statusp)
{
  struct megasas_iocpacket ioc;

  if ((mbox != NULL && (mboxlen == 0 || mboxlen > MFI_MBOX_SIZE)) ||
    (mbox == NULL && mboxlen != 0)) 
  {
    errno = EINVAL;
    return (-1);
  }

  bzero(&ioc, sizeof(ioc));
  struct megasas_dcmd_frame * dcmd = &ioc.frame.dcmd;
  ioc.host_no = bus_no;
  if (mbox)
    bcopy(mbox, dcmd->mbox.w, mboxlen);
  dcmd->cmd = MFI_CMD_DCMD;
  dcmd->timeout = 0;
  dcmd->flags = 0;
  dcmd->data_xfer_len = bufsize;
  dcmd->opcode = opcode;

  if (bufsize > 0) {
    dcmd->sge_count = 1;
    dcmd->data_xfer_len = bufsize;
    dcmd->sgl.sge32[0].phys_addr = (intptr_t)buf;
    dcmd->sgl.sge32[0].length = (uint32_t)bufsize;
    ioc.sge_count = 1;
    ioc.sgl_off = offsetof(struct megasas_dcmd_frame, sgl);
    ioc.sgl[0].iov_base = buf;
    ioc.sgl[0].iov_len = bufsize;
  }

  int fd;
  if ((fd = ::open("/dev/megaraid_sas_ioctl_node", O_RDWR)) <= 0) {
    return (errno);
  }

  int r = ioctl(fd, MEGASAS_IOC_FIRMWARE, &ioc);
  if (r < 0) {
    return (r);
  }

  if (statusp != NULL)
    *statusp = dcmd->cmd_status;
  else if (dcmd->cmd_status != MFI_STAT_OK) {
    fprintf(stderr, "command %x returned error status %x\n",
      opcode, dcmd->cmd_status);
    errno = EIO;
    return (-1);
  }
  return (0);
}

int
linux_smart_interface::megasas_pd_add_list(int bus_no, smart_device_list & devlist)
{
  /*
  * Keep fetching the list in a loop until we have a large enough
  * buffer to hold the entire list.
  */
  megasas_pd_list * list = 0;
  for (unsigned list_size = 1024; ; ) {
    list = (megasas_pd_list *)realloc(list, list_size);
    if (!list)
      throw std::bad_alloc();
    bzero(list, list_size);
    if (megasas_dcmd_cmd(bus_no, MFI_DCMD_PD_GET_LIST, list, list_size, NULL, 0,
      NULL) < 0) 
    {
      free(list);
      return (-1);
    }
    if (list->size <= list_size)
      break;
    list_size = list->size;
  }

  // adding all SCSI devices
  for (unsigned i = 0; i < list->count; i++) {
    if(list->addr[i].scsi_dev_type)
      continue; /* non disk device found */
    char line[128];
    snprintf(line, sizeof(line) - 1, "/dev/bus/%d", bus_no);
    smart_device * dev = new linux_megaraid_device(this, line, 0, list->addr[i].device_id);
    devlist.push_back(dev);
  }
  free(list);
  return (0);
}

// Return kernel release as integer ("2.6.31" -> 206031)
static unsigned get_kernel_release()
{
  struct utsname u;
  if (uname(&u))
    return 0;
  unsigned x = 0, y = 0, z = 0;
  if (!(sscanf(u.release, "%u.%u.%u", &x, &y, &z) == 3
        && x < 100 && y < 100 && z < 1000             ))
    return 0;
  return x * 100000 + y * 1000 + z;
}

// Guess device type (ata or scsi) based on device name (Linux
// specific) SCSI device name in linux can be sd, sr, scd, st, nst,
// osst, nosst and sg.
smart_device * linux_smart_interface::autodetect_smart_device(const char * name)
{
  const char * test_name = name;

  // Dereference symlinks
  struct stat st;
  std::string pathbuf;
  if (!lstat(name, &st) && S_ISLNK(st.st_mode)) {
    char * p = realpath(name, (char *)0);
    if (p) {
      pathbuf = p;
      free(p);
      test_name = pathbuf.c_str();
    }
  }

  // Remove the leading /dev/... if it's there
  static const char dev_prefix[] = "/dev/";
  if (str_starts_with(test_name, dev_prefix))
    test_name += strlen(dev_prefix);

  // form /dev/h* or h*
  if (str_starts_with(test_name, "h"))
    return new linux_ata_device(this, name, "");

  // form /dev/ide/* or ide/*
  if (str_starts_with(test_name, "ide/"))
    return new linux_ata_device(this, name, "");

  // form /dev/s* or s*
  if (str_starts_with(test_name, "s")) {

    // Try to detect possible USB->(S)ATA bridge
    unsigned short vendor_id = 0, product_id = 0, version = 0;
    if (get_usb_id(test_name, vendor_id, product_id, version)) {
      const char * usbtype = get_usb_dev_type_by_id(vendor_id, product_id, version);
      if (!usbtype)
        return 0;

      // Kernels before 2.6.29 do not support the sense data length
      // required for SAT ATA PASS-THROUGH(16)
      if (!strcmp(usbtype, "sat") && get_kernel_release() < 206029)
        usbtype = "sat,12";

      // Return SAT/USB device for this type
      // (Note: linux_scsi_device::autodetect_open() will not be called in this case)
      return get_sat_device(usbtype, new linux_scsi_device(this, name, ""));
    }

    // No USB bridge found, assume regular SCSI device
    return new linux_scsi_device(this, name, "");
  }

  // form /dev/scsi/* or scsi/*
  if (str_starts_with(test_name, "scsi/"))
    return new linux_scsi_device(this, name, "");

  // form /dev/ns* or ns*
  if (str_starts_with(test_name, "ns"))
    return new linux_scsi_device(this, name, "");

  // form /dev/os* or os*
  if (str_starts_with(test_name, "os"))
    return new linux_scsi_device(this, name, "");

  // form /dev/nos* or nos*
  if (str_starts_with(test_name, "nos"))
    return new linux_scsi_device(this, name, "");

  // form /dev/tw[ael]* or tw[ael]*
  if (str_starts_with(test_name, "tw") && strchr("ael", test_name[2]))
    return missing_option("-d 3ware,N");

  // form /dev/cciss/* or cciss/*
  if (str_starts_with(test_name, "cciss/"))
    return missing_option("-d cciss,N");

  // we failed to recognize any of the forms
  return 0;
}

smart_device * linux_smart_interface::get_custom_smart_device(const char * name, const char * type)
{
  // Marvell ?
  if (!strcmp(type, "marvell"))
    return new linux_marvell_device(this, name, type);

  // 3Ware ?
  int disknum = -1, n1 = -1, n2 = -1;
  if (sscanf(type, "3ware,%n%d%n", &n1, &disknum, &n2) == 1 || n1 == 6) {
    if (n2 != (int)strlen(type)) {
      set_err(EINVAL, "Option -d 3ware,N requires N to be a non-negative integer");
      return 0;
    }
    if (!(0 <= disknum && disknum <= 127)) {
      set_err(EINVAL, "Option -d 3ware,N (N=%d) must have 0 <= N <= 127", disknum);
      return 0;
    }

    if (!strncmp(name, "/dev/twl", 8))
      return new linux_escalade_device(this, name, linux_escalade_device::AMCC_3WARE_9700_CHAR, disknum);
    else if (!strncmp(name, "/dev/twa", 8))
      return new linux_escalade_device(this, name, linux_escalade_device::AMCC_3WARE_9000_CHAR, disknum);
    else if (!strncmp(name, "/dev/twe", 8))
      return new linux_escalade_device(this, name, linux_escalade_device::AMCC_3WARE_678K_CHAR, disknum);
    else
      return new linux_escalade_device(this, name, linux_escalade_device::AMCC_3WARE_678K, disknum);
  }

  // Areca?
  disknum = n1 = n2 = -1;
  int encnum = 1;
  if (sscanf(type, "areca,%n%d/%d%n", &n1, &disknum, &encnum, &n2) >= 1 || n1 == 6) {
    if (!(1 <= disknum && disknum <= 128)) {
      set_err(EINVAL, "Option -d areca,N/E (N=%d) must have 1 <= N <= 128", disknum);
      return 0;
    }
    if (!(1 <= encnum && encnum <= 8)) {
      set_err(EINVAL, "Option -d areca,N/E (E=%d) must have 1 <= E <= 8", encnum);
      return 0;
    }
    return new linux_areca_ata_device(this, name, disknum, encnum);
  }

  // Highpoint ?
  int controller = -1, channel = -1; disknum = 1;
  n1 = n2 = -1; int n3 = -1;
  if (sscanf(type, "hpt,%n%d/%d%n/%d%n", &n1, &controller, &channel, &n2, &disknum, &n3) >= 2 || n1 == 4) {
    int len = strlen(type);
    if (!(n2 == len || n3 == len)) {
      set_err(EINVAL, "Option '-d hpt,L/M/N' supports 2-3 items");
      return 0;
    }
    if (!(1 <= controller && controller <= 8)) {
      set_err(EINVAL, "Option '-d hpt,L/M/N' invalid controller id L supplied");
      return 0;
    }
    if (!(1 <= channel && channel <= 16)) {
      set_err(EINVAL, "Option '-d hpt,L/M/N' invalid channel number M supplied");
      return 0;
    }
    if (!(1 <= disknum && disknum <= 15)) {
      set_err(EINVAL, "Option '-d hpt,L/M/N' invalid pmport number N supplied");
      return 0;
    }
    return new linux_highpoint_device(this, name, controller, channel, disknum);
  }

#ifdef HAVE_LINUX_CCISS_IOCTL_H
  // CCISS ?
  disknum = n1 = n2 = -1;
  if (sscanf(type, "cciss,%n%d%n", &n1, &disknum, &n2) == 1 || n1 == 6) {
    if (n2 != (int)strlen(type)) {
      set_err(EINVAL, "Option -d cciss,N requires N to be a non-negative integer");
      return 0;
    }
    if (!(0 <= disknum && disknum <= 127)) {
      set_err(EINVAL, "Option -d cciss,N (N=%d) must have 0 <= N <= 127", disknum);
      return 0;
    }
    return get_sat_device("sat,auto", new linux_cciss_device(this, name, disknum));
  }
#endif // HAVE_LINUX_CCISS_IOCTL_H

  // MegaRAID ?
  if (sscanf(type, "megaraid,%d", &disknum) == 1) {
    return new linux_megaraid_device(this, name, 0, disknum);
  }
  return 0;
}

std::string linux_smart_interface::get_valid_custom_dev_types_str()
{
  return "marvell, areca,N/E, 3ware,N, hpt,L/M/N, megaraid,N"
#ifdef HAVE_LINUX_CCISS_IOCTL_H
                                              ", cciss,N"
#endif
    ;
}

} // namespace

/////////////////////////////////////////////////////////////////////////////
/// Initialize platform interface and register with smi()

void smart_interface::init()
{
  static os_linux::linux_smart_interface the_interface;
  smart_interface::set(&the_interface);
}