scsi_devinfo.c

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#include <linux/blkdev.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/slab.h>

#include <scsi/scsi_device.h>
#include <scsi/scsi_devinfo.h>

#include "scsi_priv.h"


/*
 * scsi_dev_info_list: structure to hold black/white listed devices.
 */
struct scsi_dev_info_list {
    struct list_head dev_info_list;
    char vendor[8];
    char model[16];
    unsigned flags;
    unsigned compatible; /* for use with scsi_static_device_list entries */
};

struct scsi_dev_info_list_table {
    struct list_head node;  /* our node for being on the master list */
    struct list_head scsi_dev_info_list; /* head of dev info list */
    const char *name;   /* name of list for /proc (NULL for global) */
    int key;        /* unique numeric identifier */
};


static const char spaces[] = "                "; /* 16 of them */
static unsigned scsi_default_dev_flags;
static LIST_HEAD(scsi_dev_info_list);
static char scsi_dev_flags[256];

/*
 * scsi_static_device_list: deprecated list of devices that require
 * settings that differ from the default, includes black-listed (broken)
 * devices. The entries here are added to the tail of scsi_dev_info_list
 * via scsi_dev_info_list_init.
 *
 * Do not add to this list, use the command line or proc interface to add
 * to the scsi_dev_info_list. This table will eventually go away.
 */
static struct {
    char *vendor;
    char *model;
    char *revision; /* revision known to be bad, unused */
    unsigned flags;
} scsi_static_device_list[] __initdata = {
    /*
     * The following devices are known not to tolerate a lun != 0 scan
     * for one reason or another. Some will respond to all luns,
     * others will lock up.
     */
    {"Aashima", "IMAGERY 2400SP", "1.03", BLIST_NOLUN}, /* locks up */
    {"CHINON", "CD-ROM CDS-431", "H42", BLIST_NOLUN},   /* locks up */
    {"CHINON", "CD-ROM CDS-535", "Q14", BLIST_NOLUN},   /* locks up */
    {"DENON", "DRD-25X", "V", BLIST_NOLUN},         /* locks up */
    {"HITACHI", "DK312C", "CM81", BLIST_NOLUN}, /* responds to all lun */
    {"HITACHI", "DK314C", "CR21", BLIST_NOLUN}, /* responds to all lun */
    {"IBM", "2104-DU3", NULL, BLIST_NOLUN},     /* locks up */
    {"IBM", "2104-TU3", NULL, BLIST_NOLUN},     /* locks up */
    {"IMS", "CDD521/10", "2.06", BLIST_NOLUN},  /* locks up */
    {"MAXTOR", "XT-3280", "PR02", BLIST_NOLUN}, /* locks up */
    {"MAXTOR", "XT-4380S", "B3C", BLIST_NOLUN}, /* locks up */
    {"MAXTOR", "MXT-1240S", "I1.2", BLIST_NOLUN},   /* locks up */
    {"MAXTOR", "XT-4170S", "B5A", BLIST_NOLUN}, /* locks up */
    {"MAXTOR", "XT-8760S", "B7B", BLIST_NOLUN}, /* locks up */
    {"MEDIAVIS", "RENO CD-ROMX2A", "2.03", BLIST_NOLUN},    /* responds to all lun */
    {"MICROTEK", "ScanMakerIII", "2.30", BLIST_NOLUN},  /* responds to all lun */
    {"NEC", "CD-ROM DRIVE:841", "1.0", BLIST_NOLUN},/* locks up */
    {"PHILIPS", "PCA80SC", "V4-2", BLIST_NOLUN},    /* responds to all lun */
    {"RODIME", "RO3000S", "2.33", BLIST_NOLUN}, /* locks up */
    {"SUN", "SENA", NULL, BLIST_NOLUN},     /* responds to all luns */
    /*
     * The following causes a failed REQUEST SENSE on lun 1 for
     * aha152x controller, which causes SCSI code to reset bus.
     */
    {"SANYO", "CRD-250S", "1.20", BLIST_NOLUN},
    /*
     * The following causes a failed REQUEST SENSE on lun 1 for
     * aha152x controller, which causes SCSI code to reset bus.
     */
    {"SEAGATE", "ST157N", "\004|j", BLIST_NOLUN},
    {"SEAGATE", "ST296", "921", BLIST_NOLUN},   /* responds to all lun */
    {"SEAGATE", "ST1581", "6538", BLIST_NOLUN}, /* responds to all lun */
    {"SONY", "CD-ROM CDU-541", "4.3d", BLIST_NOLUN},
    {"SONY", "CD-ROM CDU-55S", "1.0i", BLIST_NOLUN},
    {"SONY", "CD-ROM CDU-561", "1.7x", BLIST_NOLUN},
    {"SONY", "CD-ROM CDU-8012", NULL, BLIST_NOLUN},
    {"SONY", "SDT-5000", "3.17", BLIST_SELECT_NO_ATN},
    {"TANDBERG", "TDC 3600", "U07", BLIST_NOLUN},   /* locks up */
    {"TEAC", "CD-R55S", "1.0H", BLIST_NOLUN},   /* locks up */
    /*
     * The following causes a failed REQUEST SENSE on lun 1 for
     * seagate controller, which causes SCSI code to reset bus.
     */
    {"TEAC", "CD-ROM", "1.06", BLIST_NOLUN},
    {"TEAC", "MT-2ST/45S2-27", "RV M", BLIST_NOLUN},    /* responds to all lun */
    /*
     * The following causes a failed REQUEST SENSE on lun 1 for
     * seagate controller, which causes SCSI code to reset bus.
     */
    {"HP", "C1750A", "3226", BLIST_NOLUN},      /* scanjet iic */
    {"HP", "C1790A", "", BLIST_NOLUN},      /* scanjet iip */
    {"HP", "C2500A", "", BLIST_NOLUN},      /* scanjet iicx */
    {"MEDIAVIS", "CDR-H93MV", "1.31", BLIST_NOLUN}, /* locks up */
    {"MICROTEK", "ScanMaker II", "5.61", BLIST_NOLUN},  /* responds to all lun */
    {"MITSUMI", "CD-R CR-2201CS", "6119", BLIST_NOLUN}, /* locks up */
    {"NEC", "D3856", "0009", BLIST_NOLUN},
    {"QUANTUM", "LPS525S", "3110", BLIST_NOLUN},    /* locks up */
    {"QUANTUM", "PD1225S", "3110", BLIST_NOLUN},    /* locks up */
    {"QUANTUM", "FIREBALL ST4.3S", "0F0C", BLIST_NOLUN},    /* locks up */
    {"RELISYS", "Scorpio", NULL, BLIST_NOLUN},  /* responds to all lun */
    {"SANKYO", "CP525", "6.64", BLIST_NOLUN},   /* causes failed REQ SENSE, extra reset */
    {"TEXEL", "CD-ROM", "1.06", BLIST_NOLUN},
    {"transtec", "T5008", "0001", BLIST_NOREPORTLUN },
    {"YAMAHA", "CDR100", "1.00", BLIST_NOLUN},  /* locks up */
    {"YAMAHA", "CDR102", "1.00", BLIST_NOLUN},  /* locks up */
    {"YAMAHA", "CRW8424S", "1.0", BLIST_NOLUN}, /* locks up */
    {"YAMAHA", "CRW6416S", "1.0c", BLIST_NOLUN},    /* locks up */
    {"", "Scanner", "1.80", BLIST_NOLUN},   /* responds to all lun */

    /*
     * Other types of devices that have special flags.
     * Note that all USB devices should have the BLIST_INQUIRY_36 flag.
     */
    {"3PARdata", "VV", NULL, BLIST_REPORTLUN2},
    {"ADAPTEC", "AACRAID", NULL, BLIST_FORCELUN},
    {"ADAPTEC", "Adaptec 5400S", NULL, BLIST_FORCELUN},
    {"AFT PRO", "-IX CF", "0.0>", BLIST_FORCELUN},
    {"BELKIN", "USB 2 HS-CF", "1.95",  BLIST_FORCELUN | BLIST_INQUIRY_36},
    {"BROWNIE", "1200U3P", NULL, BLIST_NOREPORTLUN},
    {"BROWNIE", "1600U3P", NULL, BLIST_NOREPORTLUN},
    {"CANON", "IPUBJD", NULL, BLIST_SPARSELUN},
    {"CBOX3", "USB Storage-SMC", "300A", BLIST_FORCELUN | BLIST_INQUIRY_36},
    {"CMD", "CRA-7280", NULL, BLIST_SPARSELUN}, /* CMD RAID Controller */
    {"CNSI", "G7324", NULL, BLIST_SPARSELUN},   /* Chaparral G7324 RAID */
    {"CNSi", "G8324", NULL, BLIST_SPARSELUN},   /* Chaparral G8324 RAID */
    {"COMPAQ", "ARRAY CONTROLLER", NULL, BLIST_SPARSELUN | BLIST_LARGELUN |
        BLIST_MAX_512 | BLIST_REPORTLUN2},  /* Compaq RA4x00 */
    {"COMPAQ", "LOGICAL VOLUME", NULL, BLIST_FORCELUN | BLIST_MAX_512}, /* Compaq RA4x00 */
    {"COMPAQ", "CR3500", NULL, BLIST_FORCELUN},
    {"COMPAQ", "MSA1000", NULL, BLIST_SPARSELUN | BLIST_NOSTARTONADD},
    {"COMPAQ", "MSA1000 VOLUME", NULL, BLIST_SPARSELUN | BLIST_NOSTARTONADD},
    {"COMPAQ", "HSV110", NULL, BLIST_REPORTLUN2 | BLIST_NOSTARTONADD},
    {"DDN", "SAN DataDirector", "*", BLIST_SPARSELUN},
    {"DEC", "HSG80", NULL, BLIST_REPORTLUN2 | BLIST_NOSTARTONADD},
    {"DELL", "PV660F", NULL, BLIST_SPARSELUN},
    {"DELL", "PV660F   PSEUDO", NULL, BLIST_SPARSELUN},
    {"DELL", "PSEUDO DEVICE .", NULL, BLIST_SPARSELUN}, /* Dell PV 530F */
    {"DELL", "PV530F", NULL, BLIST_SPARSELUN},
    {"DELL", "PERCRAID", NULL, BLIST_FORCELUN},
    {"DGC", "RAID", NULL, BLIST_SPARSELUN}, /* Dell PV 650F, storage on LUN 0 */
    {"DGC", "DISK", NULL, BLIST_SPARSELUN}, /* Dell PV 650F, no storage on LUN 0 */
    {"EMC",  "Invista", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"EMC", "SYMMETRIX", NULL, BLIST_SPARSELUN | BLIST_LARGELUN | BLIST_FORCELUN},
    {"EMULEX", "MD21/S2     ESDI", NULL, BLIST_SINGLELUN},
    {"easyRAID", "16P", NULL, BLIST_NOREPORTLUN},
    {"easyRAID", "X6P", NULL, BLIST_NOREPORTLUN},
    {"easyRAID", "F8", NULL, BLIST_NOREPORTLUN},
    {"FSC", "CentricStor", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"Generic", "USB SD Reader", "1.00", BLIST_FORCELUN | BLIST_INQUIRY_36},
    {"Generic", "USB Storage-SMC", "0180", BLIST_FORCELUN | BLIST_INQUIRY_36},
    {"Generic", "USB Storage-SMC", "0207", BLIST_FORCELUN | BLIST_INQUIRY_36},
    {"HITACHI", "DF400", "*", BLIST_REPORTLUN2},
    {"HITACHI", "DF500", "*", BLIST_REPORTLUN2},
    {"HITACHI", "DISK-SUBSYSTEM", "*", BLIST_REPORTLUN2},
    {"HITACHI", "HUS1530", "*", BLIST_NO_DIF},
    {"HITACHI", "OPEN-", "*", BLIST_REPORTLUN2},
    {"HITACHI", "OP-C-", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"HITACHI", "3380-", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"HITACHI", "3390-", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"HITACHI", "6586-", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"HITACHI", "6588-", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"HP", "A6189A", NULL, BLIST_SPARSELUN | BLIST_LARGELUN},   /* HP VA7400 */
    {"HP", "OPEN-", "*", BLIST_REPORTLUN2}, /* HP XP Arrays */
    {"HP", "NetRAID-4M", NULL, BLIST_FORCELUN},
    {"HP", "HSV100", NULL, BLIST_REPORTLUN2 | BLIST_NOSTARTONADD},
    {"HP", "C1557A", NULL, BLIST_FORCELUN},
    {"HP", "C3323-300", "4269", BLIST_NOTQ},
    {"HP", "C5713A", NULL, BLIST_NOREPORTLUN},
    {"HP", "DF400", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"HP", "DF500", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"HP", "DF600", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"HP", "OP-C-", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"HP", "3380-", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"HP", "3390-", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"HP", "6586-", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"HP", "6588-", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"IBM", "AuSaV1S2", NULL, BLIST_FORCELUN},
    {"IBM", "ProFibre 4000R", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"IBM", "2105", NULL, BLIST_RETRY_HWERROR},
    {"iomega", "jaz 1GB", "J.86", BLIST_NOTQ | BLIST_NOLUN},
    {"IOMEGA", "ZIP", NULL, BLIST_NOTQ | BLIST_NOLUN},
    {"IOMEGA", "Io20S         *F", NULL, BLIST_KEY},
    {"INSITE", "Floptical   F*8I", NULL, BLIST_KEY},
    {"INSITE", "I325VM", NULL, BLIST_KEY},
    {"iRiver", "iFP Mass Driver", NULL, BLIST_NOT_LOCKABLE | BLIST_INQUIRY_36},
    {"LASOUND", "CDX7405", "3.10", BLIST_MAX5LUN | BLIST_SINGLELUN},
    {"MATSHITA", "PD-1", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
    {"MATSHITA", "DMC-LC5", NULL, BLIST_NOT_LOCKABLE | BLIST_INQUIRY_36},
    {"MATSHITA", "DMC-LC40", NULL, BLIST_NOT_LOCKABLE | BLIST_INQUIRY_36},
    {"Medion", "Flash XL  MMC/SD", "2.6D", BLIST_FORCELUN},
    {"MegaRAID", "LD", NULL, BLIST_FORCELUN},
    {"MICROP", "4110", NULL, BLIST_NOTQ},
    {"MYLEX", "DACARMRB", "*", BLIST_REPORTLUN2},
    {"nCipher", "Fastness Crypto", NULL, BLIST_FORCELUN},
    {"NAKAMICH", "MJ-4.8S", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
    {"NAKAMICH", "MJ-5.16S", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
    {"NEC", "PD-1 ODX654P", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
    {"NEC", "iStorage", NULL, BLIST_REPORTLUN2},
    {"NRC", "MBR-7", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
    {"NRC", "MBR-7.4", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
    {"PIONEER", "CD-ROM DRM-600", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
    {"PIONEER", "CD-ROM DRM-602X", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
    {"PIONEER", "CD-ROM DRM-604X", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
    {"PIONEER", "CD-ROM DRM-624X", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
    {"Promise", "", NULL, BLIST_SPARSELUN},
    {"QUANTUM", "XP34301", "1071", BLIST_NOTQ},
    {"REGAL", "CDC-4X", NULL, BLIST_MAX5LUN | BLIST_SINGLELUN},
    {"SanDisk", "ImageMate CF-SD1", NULL, BLIST_FORCELUN},
    {"SEAGATE", "ST34555N", "0930", BLIST_NOTQ},    /* Chokes on tagged INQUIRY */
    {"SEAGATE", "ST3390N", "9546", BLIST_NOTQ},
    {"SGI", "RAID3", "*", BLIST_SPARSELUN},
    {"SGI", "RAID5", "*", BLIST_SPARSELUN},
    {"SGI", "TP9100", "*", BLIST_REPORTLUN2},
    {"SGI", "Universal Xport", "*", BLIST_NO_ULD_ATTACH},
    {"IBM", "Universal Xport", "*", BLIST_NO_ULD_ATTACH},
    {"SUN", "Universal Xport", "*", BLIST_NO_ULD_ATTACH},
    {"DELL", "Universal Xport", "*", BLIST_NO_ULD_ATTACH},
    {"SMSC", "USB 2 HS-CF", NULL, BLIST_SPARSELUN | BLIST_INQUIRY_36},
    {"SONY", "CD-ROM CDU-8001", NULL, BLIST_BORKEN},
    {"SONY", "TSL", NULL, BLIST_FORCELUN},      /* DDS3 & DDS4 autoloaders */
    {"ST650211", "CF", NULL, BLIST_RETRY_HWERROR},
    {"SUN", "T300", "*", BLIST_SPARSELUN},
    {"SUN", "T4", "*", BLIST_SPARSELUN},
    {"TEXEL", "CD-ROM", "1.06", BLIST_BORKEN},
    {"Tornado-", "F4", "*", BLIST_NOREPORTLUN},
    {"TOSHIBA", "CDROM", NULL, BLIST_ISROM},
    {"TOSHIBA", "CD-ROM", NULL, BLIST_ISROM},
    {"Traxdata", "CDR4120", NULL, BLIST_NOLUN}, /* locks up */
    {"USB2.0", "SMARTMEDIA/XD", NULL, BLIST_FORCELUN | BLIST_INQUIRY_36},
    {"WangDAT", "Model 2600", "01.7", BLIST_SELECT_NO_ATN},
    {"WangDAT", "Model 3200", "02.2", BLIST_SELECT_NO_ATN},
    {"WangDAT", "Model 1300", "02.4", BLIST_SELECT_NO_ATN},
    {"WDC WD25", "00JB-00FUA0", NULL, BLIST_NOREPORTLUN},
    {"XYRATEX", "RS", "*", BLIST_SPARSELUN | BLIST_LARGELUN},
    {"Zzyzx", "RocketStor 500S", NULL, BLIST_SPARSELUN},
    {"Zzyzx", "RocketStor 2000", NULL, BLIST_SPARSELUN},
    { NULL, NULL, NULL, 0 },
};

static struct scsi_dev_info_list_table *scsi_devinfo_lookup_by_key(int key)
{
    struct scsi_dev_info_list_table *devinfo_table;
    int found = 0;

    list_for_each_entry(devinfo_table, &scsi_dev_info_list, node)
        if (devinfo_table->key == key) {
            found = 1;
            break;
        }
    if (!found)
        return ERR_PTR(-EINVAL);

    return devinfo_table;
}

/*
 * scsi_strcpy_devinfo: called from scsi_dev_info_list_add to copy into
 * devinfo vendor and model strings.
 */
static void scsi_strcpy_devinfo(char *name, char *to, size_t to_length,
                char *from, int compatible)
{
    size_t from_length;

    from_length = strlen(from);
    strncpy(to, from, min(to_length, from_length));
    if (from_length < to_length) {
        if (compatible) {
            /*
             * NUL terminate the string if it is short.
             */
            to[from_length] = '\0';
        } else {
            /* 
             * space pad the string if it is short. 
             */
            strncpy(&to[from_length], spaces,
                to_length - from_length);
        }
    }
    if (from_length > to_length)
         printk(KERN_WARNING "%s: %s string '%s' is too long\n",
            __func__, name, from);
}

static int scsi_dev_info_list_add(int compatible, char *vendor, char *model,
                char *strflags, int flags)
{
    return scsi_dev_info_list_add_keyed(compatible, vendor, model,
                        strflags, flags,
                        SCSI_DEVINFO_GLOBAL);
}

int scsi_dev_info_list_add_keyed(int compatible, char *vendor, char *model,
                 char *strflags, int flags, int key)
{
    struct scsi_dev_info_list *devinfo;
    struct scsi_dev_info_list_table *devinfo_table =
        scsi_devinfo_lookup_by_key(key);

    if (IS_ERR(devinfo_table))
        return PTR_ERR(devinfo_table);

    devinfo = kmalloc(sizeof(*devinfo), GFP_KERNEL);
    if (!devinfo) {
        printk(KERN_ERR "%s: no memory\n", __func__);
        return -ENOMEM;
    }

    scsi_strcpy_devinfo("vendor", devinfo->vendor, sizeof(devinfo->vendor),
                vendor, compatible);
    scsi_strcpy_devinfo("model", devinfo->model, sizeof(devinfo->model),
                model, compatible);

    if (strflags)
        devinfo->flags = simple_strtoul(strflags, NULL, 0);
    else
        devinfo->flags = flags;

    devinfo->compatible = compatible;

    if (compatible)
        list_add_tail(&devinfo->dev_info_list,
                  &devinfo_table->scsi_dev_info_list);
    else
        list_add(&devinfo->dev_info_list,
             &devinfo_table->scsi_dev_info_list);

    return 0;
}
EXPORT_SYMBOL(scsi_dev_info_list_add_keyed);

int scsi_dev_info_list_del_keyed(char *vendor, char *model, int key)
{
    struct scsi_dev_info_list *devinfo, *found = NULL;
    struct scsi_dev_info_list_table *devinfo_table =
        scsi_devinfo_lookup_by_key(key);

    if (IS_ERR(devinfo_table))
        return PTR_ERR(devinfo_table);

    list_for_each_entry(devinfo, &devinfo_table->scsi_dev_info_list,
                dev_info_list) {
        if (devinfo->compatible) {
            /*
             * Behave like the older version of get_device_flags.
             */
            size_t max;
            /*
             * XXX why skip leading spaces? If an odd INQUIRY
             * value, that should have been part of the
             * scsi_static_device_list[] entry, such as "  FOO"
             * rather than "FOO". Since this code is already
             * here, and we don't know what device it is
             * trying to work with, leave it as-is.
             */
            max = 8;    /* max length of vendor */
            while ((max > 0) && *vendor == ' ') {
                max--;
                vendor++;
            }
            /*
             * XXX removing the following strlen() would be
             * good, using it means that for a an entry not in
             * the list, we scan every byte of every vendor
             * listed in scsi_static_device_list[], and never match
             * a single one (and still have to compare at
             * least the first byte of each vendor).
             */
            if (memcmp(devinfo->vendor, vendor,
                    min(max, strlen(devinfo->vendor))))
                continue;
            /*
             * Skip spaces again.
             */
            max = 16;   /* max length of model */
            while ((max > 0) && *model == ' ') {
                max--;
                model++;
            }
            if (memcmp(devinfo->model, model,
                   min(max, strlen(devinfo->model))))
                continue;
            found = devinfo;
        } else {
            if (!memcmp(devinfo->vendor, vendor,
                     sizeof(devinfo->vendor)) &&
                 !memcmp(devinfo->model, model,
                      sizeof(devinfo->model)))
                found = devinfo;
        }
        if (found)
            break;
    }

    if (found) {
        list_del(&found->dev_info_list);
        kfree(found);
        return 0;
    }

    return -ENOENT;
}
EXPORT_SYMBOL(scsi_dev_info_list_del_keyed);

static int scsi_dev_info_list_add_str(char *dev_list)
{
    char *vendor, *model, *strflags, *next;
    char *next_check;
    int res = 0;

    next = dev_list;
    if (next && next[0] == '"') {
        /*
         * Ignore both the leading and trailing quote.
         */
        next++;
        next_check = ",\"";
    } else {
        next_check = ",";
    }

    /*
     * For the leading and trailing '"' case, the for loop comes
     * through the last time with vendor[0] == '\0'.
     */
    for (vendor = strsep(&next, ":"); vendor && (vendor[0] != '\0')
         && (res == 0); vendor = strsep(&next, ":")) {
        strflags = NULL;
        model = strsep(&next, ":");
        if (model)
            strflags = strsep(&next, next_check);
        if (!model || !strflags) {
            printk(KERN_ERR "%s: bad dev info string '%s' '%s'"
                   " '%s'\n", __func__, vendor, model,
                   strflags);
            res = -EINVAL;
        } else
            res = scsi_dev_info_list_add(0 /* compatible */, vendor,
                             model, strflags, 0);
    }
    return res;
}

int scsi_get_device_flags(struct scsi_device *sdev,
              const unsigned char *vendor,
              const unsigned char *model)
{
    return scsi_get_device_flags_keyed(sdev, vendor, model,
                       SCSI_DEVINFO_GLOBAL);
}


int scsi_get_device_flags_keyed(struct scsi_device *sdev,
                const unsigned char *vendor,
                const unsigned char *model,
                int key)
{
    struct scsi_dev_info_list *devinfo;
    struct scsi_dev_info_list_table *devinfo_table;

    devinfo_table = scsi_devinfo_lookup_by_key(key);

    if (IS_ERR(devinfo_table))
        return PTR_ERR(devinfo_table);

    list_for_each_entry(devinfo, &devinfo_table->scsi_dev_info_list,
                dev_info_list) {
        if (devinfo->compatible) {
            /*
             * Behave like the older version of get_device_flags.
             */
            size_t max;
            /*
             * XXX why skip leading spaces? If an odd INQUIRY
             * value, that should have been part of the
             * scsi_static_device_list[] entry, such as "  FOO"
             * rather than "FOO". Since this code is already
             * here, and we don't know what device it is
             * trying to work with, leave it as-is.
             */
            max = 8;    /* max length of vendor */
            while ((max > 0) && *vendor == ' ') {
                max--;
                vendor++;
            }
            /*
             * XXX removing the following strlen() would be
             * good, using it means that for a an entry not in
             * the list, we scan every byte of every vendor
             * listed in scsi_static_device_list[], and never match
             * a single one (and still have to compare at
             * least the first byte of each vendor).
             */
            if (memcmp(devinfo->vendor, vendor,
                    min(max, strlen(devinfo->vendor))))
                continue;
            /*
             * Skip spaces again.
             */
            max = 16;   /* max length of model */
            while ((max > 0) && *model == ' ') {
                max--;
                model++;
            }
            if (memcmp(devinfo->model, model,
                   min(max, strlen(devinfo->model))))
                continue;
            return devinfo->flags;
        } else {
            if (!memcmp(devinfo->vendor, vendor,
                     sizeof(devinfo->vendor)) &&
                 !memcmp(devinfo->model, model,
                      sizeof(devinfo->model)))
                return devinfo->flags;
        }
    }
    /* nothing found, return nothing */
    if (key != SCSI_DEVINFO_GLOBAL)
        return 0;

    /* except for the global list, where we have an exception */
    if (sdev->sdev_bflags)
        return sdev->sdev_bflags;

    return scsi_default_dev_flags;
}
EXPORT_SYMBOL(scsi_get_device_flags_keyed);

#ifdef CONFIG_SCSI_PROC_FS
struct double_list {
    struct list_head *top;
    struct list_head *bottom;
};

static int devinfo_seq_show(struct seq_file *m, void *v)
{
    struct double_list *dl = v;
    struct scsi_dev_info_list_table *devinfo_table =
        list_entry(dl->top, struct scsi_dev_info_list_table, node);
    struct scsi_dev_info_list *devinfo =
        list_entry(dl->bottom, struct scsi_dev_info_list,
               dev_info_list);

    if (devinfo_table->scsi_dev_info_list.next == dl->bottom &&
        devinfo_table->name)
        seq_printf(m, "[%s]:\n", devinfo_table->name);

    seq_printf(m, "'%.8s' '%.16s' 0x%x\n",
           devinfo->vendor, devinfo->model, devinfo->flags);
    return 0;
}

static void *devinfo_seq_start(struct seq_file *m, loff_t *ppos)
{
    struct double_list *dl = kmalloc(sizeof(*dl), GFP_KERNEL);
    loff_t pos = *ppos;

    if (!dl)
        return NULL;

    list_for_each(dl->top, &scsi_dev_info_list) {
        struct scsi_dev_info_list_table *devinfo_table =
            list_entry(dl->top, struct scsi_dev_info_list_table,
                   node);
        list_for_each(dl->bottom, &devinfo_table->scsi_dev_info_list)
            if (pos-- == 0)
                return dl;
    }

    kfree(dl);
    return NULL;
}

static void *devinfo_seq_next(struct seq_file *m, void *v, loff_t *ppos)
{
    struct double_list *dl = v;
    struct scsi_dev_info_list_table *devinfo_table =
        list_entry(dl->top, struct scsi_dev_info_list_table, node);

    ++*ppos;
    dl->bottom = dl->bottom->next;
    while (&devinfo_table->scsi_dev_info_list == dl->bottom) {
        dl->top = dl->top->next;
        if (dl->top == &scsi_dev_info_list) {
            kfree(dl);
            return NULL;
        }
        devinfo_table = list_entry(dl->top,
                       struct scsi_dev_info_list_table,
                       node);
        dl->bottom = devinfo_table->scsi_dev_info_list.next;
    }

    return dl;
}

static void devinfo_seq_stop(struct seq_file *m, void *v)
{
    kfree(v);
}

static const struct seq_operations scsi_devinfo_seq_ops = {
    .start  = devinfo_seq_start,
    .next   = devinfo_seq_next,
    .stop   = devinfo_seq_stop,
    .show   = devinfo_seq_show,
};

static int proc_scsi_devinfo_open(struct inode *inode, struct file *file)
{
    return seq_open(file, &scsi_devinfo_seq_ops);
}

/* 
 * proc_scsi_dev_info_write - allow additions to scsi_dev_info_list via /proc.
 *
 * Description: Adds a black/white list entry for vendor and model with an
 * integer value of flag to the scsi device info list.
 * To use, echo "vendor:model:flag" > /proc/scsi/device_info
 */
static ssize_t proc_scsi_devinfo_write(struct file *file,
                       const char __user *buf,
                       size_t length, loff_t *ppos)
{
    char *buffer;
    ssize_t err = length;

    if (!buf || length>PAGE_SIZE)
        return -EINVAL;
    if (!(buffer = (char *) __get_free_page(GFP_KERNEL)))
        return -ENOMEM;
    if (copy_from_user(buffer, buf, length)) {
        err =-EFAULT;
        goto out;
    }

    if (length < PAGE_SIZE)
        buffer[length] = '\0';
    else if (buffer[PAGE_SIZE-1]) {
        err = -EINVAL;
        goto out;
    }

    scsi_dev_info_list_add_str(buffer);

out:
    free_page((unsigned long)buffer);
    return err;
}

static const struct file_operations scsi_devinfo_proc_fops = {
    .owner      = THIS_MODULE,
    .open       = proc_scsi_devinfo_open,
    .read       = seq_read,
    .write      = proc_scsi_devinfo_write,
    .llseek     = seq_lseek,
    .release    = seq_release,
};
#endif /* CONFIG_SCSI_PROC_FS */

module_param_string(dev_flags, scsi_dev_flags, sizeof(scsi_dev_flags), 0);
MODULE_PARM_DESC(dev_flags,
     "Given scsi_dev_flags=vendor:model:flags[,v:m:f] add black/white"
     " list entries for vendor and model with an integer value of flags"
     " to the scsi device info list");

module_param_named(default_dev_flags, scsi_default_dev_flags, int, S_IRUGO|S_IWUSR);
MODULE_PARM_DESC(default_dev_flags,
         "scsi default device flag integer value");

void scsi_exit_devinfo(void)
{
#ifdef CONFIG_SCSI_PROC_FS
    remove_proc_entry("scsi/device_info", NULL);
#endif

    scsi_dev_info_remove_list(SCSI_DEVINFO_GLOBAL);
}

int scsi_dev_info_add_list(int key, const char *name)
{
    struct scsi_dev_info_list_table *devinfo_table =
        scsi_devinfo_lookup_by_key(key);

    if (!IS_ERR(devinfo_table))
        /* list already exists */
        return -EEXIST;

    devinfo_table = kmalloc(sizeof(*devinfo_table), GFP_KERNEL);

    if (!devinfo_table)
        return -ENOMEM;

    INIT_LIST_HEAD(&devinfo_table->node);
    INIT_LIST_HEAD(&devinfo_table->scsi_dev_info_list);
    devinfo_table->name = name;
    devinfo_table->key = key;
    list_add_tail(&devinfo_table->node, &scsi_dev_info_list);

    return 0;
}
EXPORT_SYMBOL(scsi_dev_info_add_list);

int scsi_dev_info_remove_list(int key)
{
    struct list_head *lh, *lh_next;
    struct scsi_dev_info_list_table *devinfo_table =
        scsi_devinfo_lookup_by_key(key);

    if (IS_ERR(devinfo_table))
        /* no such list */
        return -EINVAL;

    /* remove from the master list */
    list_del(&devinfo_table->node);

    list_for_each_safe(lh, lh_next, &devinfo_table->scsi_dev_info_list) {
        struct scsi_dev_info_list *devinfo;

        devinfo = list_entry(lh, struct scsi_dev_info_list,
                     dev_info_list);
        kfree(devinfo);
    }
    kfree(devinfo_table);

    return 0;
}
EXPORT_SYMBOL(scsi_dev_info_remove_list);

int __init scsi_init_devinfo(void)
{
#ifdef CONFIG_SCSI_PROC_FS
    struct proc_dir_entry *p;
#endif
    int error, i;

    error = scsi_dev_info_add_list(SCSI_DEVINFO_GLOBAL, NULL);
    if (error)
        return error;

    error = scsi_dev_info_list_add_str(scsi_dev_flags);
    if (error)
        goto out;

    for (i = 0; scsi_static_device_list[i].vendor; i++) {
        error = scsi_dev_info_list_add(1 /* compatibile */,
                scsi_static_device_list[i].vendor,
                scsi_static_device_list[i].model,
                NULL,
                scsi_static_device_list[i].flags);
        if (error)
            goto out;
    }

#ifdef CONFIG_SCSI_PROC_FS
    p = proc_create("scsi/device_info", 0, NULL, &scsi_devinfo_proc_fops);
    if (!p) {
        error = -ENOMEM;
        goto out;
    }
#endif /* CONFIG_SCSI_PROC_FS */

 out:
    if (error)
        scsi_exit_devinfo();
    return error;
}