/*-
 * Copyright (c) 1997, 1998
 *      Nan Yang Computer Services Limited.  All rights reserved.
 *
 *  Written by Greg Lehey
 *
 *  This software is distributed under the so-called ``Berkeley
 *  License'':
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Nan Yang Computer
 *      Services Limited.
 * 4. Neither the name of the Company nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * This software is provided ``as is'', and any express or implied
 * warranties, including, but not limited to, the implied warranties of
 * merchantability and fitness for a particular purpose are disclaimed.
 * In no event shall the company or contributors be liable for any
 * direct, indirect, incidental, special, exemplary, or consequential
 * damages (including, but not limited to, procurement of substitute
 * goods or services; loss of use, data, or profits; or business
 * interruption) however caused and on any theory of liability, whether
 * in contract, strict liability, or tort (including negligence or
 * otherwise) arising in any way out of the use of this software, even if
 * advised of the possibility of such damage.
 *
 * $Id: vinum.c,v 1.33 2001/01/09 06:19:15 grog Exp grog $
 * $FreeBSD: src/sys/dev/vinum/vinum.c,v 1.38.2.3 2003/01/07 12:14:16 joerg Exp $
 */

#define STATIC static                                       /* nothing while we're testing XXX */

#include "vinumhdr.h"
#include <sys/sysmsg.h>                                     /* for sync(2) */
#include <sys/poll.h>                                       /* XXX: poll ops used in kq filters */
#include <sys/event.h>
#include <sys/udev.h>
#ifdef VINUMDEBUG
#include <sys/reboot.h>
int debug = 0;
extern int total_malloced;
extern int malloccount;
extern struct mc malloced[];
#endif
#include "request.h"

struct dev_ops vinum_ops =
{
        { "vinum", 0, D_DISK },
        .d_open =       vinumopen,
        .d_close =      vinumclose,
        .d_read =       physread,
        .d_write =      physwrite,
        .d_ioctl =      vinumioctl,
        .d_kqfilter =   vinumkqfilter,
        .d_strategy =   vinumstrategy,
        .d_dump =       vinumdump,
        .d_psize =      vinumsize,
};

/* Called by main() during pseudo-device attachment. */
STATIC void vinumattach(void *);

STATIC int vinum_modevent(module_t mod, modeventtype_t type, void *unused);
STATIC void vinum_initconf(void);

struct _vinum_conf vinum_conf;                              /* configuration information */
cdev_t  vinum_super_dev;
cdev_t  vinum_wsuper_dev;
cdev_t  vinum_daemon_dev;

/*
 * Called by main() during pseudo-device attachment.  All we need
 * to do is allocate enough space for devices to be configured later, and
 * add devsw entries.
 */
static void
vinumattach(void *dummy)
{
    char *cp, *cp1, *cp2, **drives;
    int i, rv;
    struct volume *vol;

    /* modload should prevent multiple loads, so this is worth a panic */
    if ((vinum_conf.flags & VF_LOADED) != 0)
        panic("vinum: already loaded");

    log(LOG_INFO, "vinum: loaded\n");
    vinum_conf.flags |= VF_LOADED;                          /* we're loaded now */

    daemonq = NULL;                                         /* initialize daemon's work queue */
    dqend = NULL;

#if 0
    dev_ops_add(&vinum_ops, 0, 0);
#endif

    vinum_initconf();

    /*
     * Create superdev, wrongsuperdev, and controld devices.
     */
    vinum_super_dev =   make_dev(&vinum_ops, VINUM_SUPERDEV,
                                 UID_ROOT, GID_WHEEL, 0600,
                                 VINUM_SUPERDEV_BASE);
    vinum_wsuper_dev =  make_dev(&vinum_ops, VINUM_WRONGSUPERDEV,
                                 UID_ROOT, GID_WHEEL, 0600,
                                 VINUM_WRONGSUPERDEV_BASE);
    vinum_daemon_dev =  make_dev(&vinum_ops, VINUM_DAEMON_DEV,
                                 UID_ROOT, GID_WHEEL, 0600,
                                 VINUM_DAEMON_DEV_BASE);

    /*
     * See if the loader has passed us a disk to
     * read the initial configuration from.
     */
    if ((cp = kgetenv("vinum.drives")) != NULL) {
        for (cp1 = cp, i = 0, drives = NULL; *cp1 != '\0'; i++) {
            cp2 = cp1;
            while (*cp1 != '\0' && *cp1 != ',' && *cp1 != ' ')
                cp1++;
            if (*cp1 != '\0')
                *cp1++ = '\0';
            drives = krealloc(drives, (unsigned long)((i + 1) * sizeof(char *)),
                             M_TEMP, M_WAITOK);
            drives[i] = cp2;
        }
        if (i == 0)
            goto bailout;
        rv = vinum_scandisk(drives, i);
        if (rv)
            log(LOG_NOTICE, "vinum_scandisk() returned %d", rv);
    bailout:
        kfree(drives, M_TEMP);
    }
    if ((cp = kgetenv("vinum.root")) != NULL) {
        for (i = 0; i < vinum_conf.volumes_used; i++) {
            vol = &vinum_conf.volume[i];
            if ((vol->state == volume_up)
                && (strcmp (vol->name, cp) == 0) 
            ) {
                rootdev = make_dev(&vinum_ops, i, UID_ROOT, GID_OPERATOR,
                                0640, VINUM_BASE "vinumroot");
                udev_dict_set_cstr(rootdev, "subsystem", "raid");
                udev_dict_set_cstr(rootdev, "disk-type", "raid");
                log(LOG_INFO, "vinum: using volume %s for root device\n", cp);
                break;
            }
        }
    }
}

/*
 * Check if we have anything open.  If confopen is != 0,
 * that goes for the super device as well, otherwise
 * only for volumes.
 *
 * Return 0 if not inactive, 1 if inactive.
 */
int
vinum_inactive(int confopen)
{
    int i;
    int can_do = 1;                                         /* assume we can do it */

    if (confopen && (vinum_conf.flags & VF_OPEN))           /* open by vinum(8)? */
        return 0;                                           /* can't do it while we're open */
    lock_config();
    for (i = 0; i < vinum_conf.volumes_allocated; i++) {
        if ((VOL[i].state > volume_down)
            && (VOL[i].flags & VF_OPEN)) {                  /* volume is open */
            can_do = 0;
            break;
        }
    }
    unlock_config();
    return can_do;
}

/*
 * Free all structures.
 * If cleardrive is 0, save the configuration; otherwise
 * remove the configuration from the drive.
 *
 * Before coming here, ensure that no volumes are open.
 */
void
free_vinum(int cleardrive)
{
    union daemoninfo di = { .nothing = 0 };
    int i;
    int drives_allocated = vinum_conf.drives_allocated;

    if (DRIVE != NULL) {
        if (cleardrive) {                                   /* remove the vinum config */
            for (i = 0; i < drives_allocated; i++)
                remove_drive(i);                            /* remove the drive */
        } else {                                            /* keep the config */
            for (i = 0; i < drives_allocated; i++)
                free_drive(&DRIVE[i]);                      /* close files and things */
        }
        Free(DRIVE);
    }
    while ((vinum_conf.flags & (VF_STOPPING | VF_DAEMONOPEN))
        == (VF_STOPPING | VF_DAEMONOPEN)) {                 /* at least one daemon open, we're stopping */
        queue_daemon_request(daemonrq_return, di);          /* stop the daemon */
        tsleep(&vinumclose, 0, "vstop", 1);                 /* and wait for it */
    }
    if (SD != NULL) {
        for (i = 0; i < vinum_conf.subdisks_allocated; i++) {
            struct sd *sd = &vinum_conf.sd[i];
            if (sd->sd_dev) {
                destroy_dev(sd->sd_dev);
                sd->sd_dev = NULL;
            }
        }
        Free(SD);
    }
    if (PLEX != NULL) {
        for (i = 0; i < vinum_conf.plexes_allocated; i++) {
            struct plex *plex = &vinum_conf.plex[i];

            if (plex->plex_dev) {
                destroy_dev(plex->plex_dev);
                plex->plex_dev = NULL;
            }

            if (plex->state != plex_unallocated) {          /* we have real data there */
                if (plex->sdnos)
                    Free(plex->sdnos);
            }
        }
        Free(PLEX);
    }
    if (VOL != NULL) {
        for (i = 0; i < vinum_conf.volumes_allocated; i++) {
            struct volume *vol = &vinum_conf.volume[i];

            if (vol->vol_dev) {
                destroy_dev(vol->vol_dev);
                vol->vol_dev = NULL;
            }
        }
        Free(VOL);
    }
    bzero(&vinum_conf, sizeof(vinum_conf));
    vinum_initconf();
}

STATIC void
vinum_initconf(void)
{
    vinum_conf.physbufs = nswbuf_kva / 2 + 1;

    /* allocate space: drives... */
    DRIVE = (struct drive *) Malloc(sizeof(struct drive) * INITIAL_DRIVES);
    CHECKALLOC(DRIVE, "vinum: no memory\n");
    bzero(DRIVE, sizeof(struct drive) * INITIAL_DRIVES);
    vinum_conf.drives_allocated = INITIAL_DRIVES;
    vinum_conf.drives_used = 0;

    /* volumes, ... */
    VOL = (struct volume *) Malloc(sizeof(struct volume) * INITIAL_VOLUMES);
    CHECKALLOC(VOL, "vinum: no memory\n");
    bzero(VOL, sizeof(struct volume) * INITIAL_VOLUMES);
    vinum_conf.volumes_allocated = INITIAL_VOLUMES;
    vinum_conf.volumes_used = 0;

    /* plexes, ... */
    PLEX = (struct plex *) Malloc(sizeof(struct plex) * INITIAL_PLEXES);
    CHECKALLOC(PLEX, "vinum: no memory\n");
    bzero(PLEX, sizeof(struct plex) * INITIAL_PLEXES);
    vinum_conf.plexes_allocated = INITIAL_PLEXES;
    vinum_conf.plexes_used = 0;

    /* and subdisks */
    SD = (struct sd *) Malloc(sizeof(struct sd) * INITIAL_SUBDISKS);
    CHECKALLOC(SD, "vinum: no memory\n");
    bzero(SD, sizeof(struct sd) * INITIAL_SUBDISKS);
    vinum_conf.subdisks_allocated = INITIAL_SUBDISKS;
    vinum_conf.subdisks_used = 0;
}

STATIC int
vinum_modevent(module_t mod, modeventtype_t type, void *unused)
{
    switch (type) {
    case MOD_LOAD:
        vinumattach(NULL);
        return 0;                                           /* OK */
    case MOD_UNLOAD:
        if (!vinum_inactive(1))                             /* is anything open? */
            return EBUSY;                                   /* yes, we can't do it */
        vinum_conf.flags |= VF_STOPPING;                    /* note that we want to stop */
        sys_sync(NULL, NULL);                       /* write out buffers */
        free_vinum(0);                                      /* clean up */

        if (vinum_super_dev) {
            destroy_dev(vinum_super_dev);
            vinum_super_dev = NULL;
        }
        if (vinum_wsuper_dev) {
            destroy_dev(vinum_wsuper_dev);
            vinum_wsuper_dev = NULL;
        }
        if (vinum_daemon_dev) {
            destroy_dev(vinum_daemon_dev);
            vinum_daemon_dev = NULL;
        }

        sync_devs();
#ifdef VINUMDEBUG
        if (total_malloced) {
            int i;
#ifdef INVARIANTS
            int *poke;
#endif

            for (i = 0; i < malloccount; i++) {
                if (debug & DEBUG_WARNINGS)                 /* want to hear about them */
                    log(LOG_WARNING,
                        "vinum: exiting with %d bytes malloced from %s:%d\n",
                        malloced[i].size,
                        malloced[i].file,
                        malloced[i].line);
#ifdef INVARIANTS
                poke = &((int *) malloced[i].address)
                    [malloced[i].size / (2 * sizeof(int))]; /* middle of the area */
                if (*poke == 0xdeadc0de)                    /* already freed */
                    log(LOG_ERR,
                        "vinum: exiting with malloc table inconsistency at %p from %s:%d\n",
                        malloced[i].address,
                        malloced[i].file,
                        malloced[i].line);
#endif
                Free(malloced[i].address);
            }
        }
#endif
        dev_ops_remove_all(&vinum_ops);
        log(LOG_INFO, "vinum: unloaded\n");                 /* tell the world */
        return 0;
    default:
        break;
    }
    return 0;
}

moduledata_t vinum_mod =
{
    "vinum",
    (modeventhand_t) vinum_modevent,
    0
};
DECLARE_MODULE(vinum, vinum_mod, SI_SUB_RAID, SI_ORDER_MIDDLE);
MODULE_VERSION(vinum, 1);

/* ARGSUSED */
/* Open a vinum object */
int
vinumopen(struct dev_open_args *ap)
{
    cdev_t dev = ap->a_head.a_dev;
    int error;
    unsigned int index;
    struct volume *vol;
    struct plex *plex;
    struct sd *sd;
    int devminor;                                           /* minor number */

    devminor = minor(dev);
    error = 0;
    /* First, decide what we're looking at */
    switch (DEVTYPE(dev)) {
    case VINUM_VOLUME_TYPE:
        index = Volno(dev);
        if (index >= vinum_conf.volumes_allocated)
            return ENXIO;                                   /* no such device */
        vol = &VOL[index];

        switch (vol->state) {
        case volume_unallocated:
        case volume_uninit:
            return ENXIO;

        case volume_up:
            vol->flags |= VF_OPEN;                          /* note we're open */
            return 0;

        case volume_down:
            return EIO;

        default:
            return EINVAL;
        }

    case VINUM_PLEX_TYPE:
        if (Volno(dev) >= vinum_conf.volumes_allocated)
            return ENXIO;
        /* FALLTHROUGH */

    case VINUM_RAWPLEX_TYPE:
        index = Plexno(dev);                                /* get plex index in vinum_conf */
        if (index >= vinum_conf.plexes_allocated)
            return ENXIO;                                   /* no such device */
        plex = &PLEX[index];

        switch (plex->state) {
        case plex_referenced:
        case plex_unallocated:
            return EINVAL;

        default:
            plex->flags |= VF_OPEN;                         /* note we're open */
            return 0;
        }

    case VINUM_SD_TYPE:
        if ((Volno(dev) >= vinum_conf.volumes_allocated)    /* no such volume */
        ||(Plexno(dev) >= vinum_conf.plexes_allocated))     /* or no such plex */
            return ENXIO;                                   /* no such device */

        /* FALLTHROUGH */

    case VINUM_RAWSD_TYPE:
        index = Sdno(dev);                                  /* get the subdisk number */
        if ((index >= vinum_conf.subdisks_allocated)        /* not a valid SD entry */
        ||(SD[index].state < sd_init))                      /* or SD is not real */
            return ENXIO;                                   /* no such device */
        sd = &SD[index];

        /*
         * Opening a subdisk is always a special operation, so we
         * ignore the state as long as it represents a real subdisk
         */
        switch (sd->state) {
        case sd_unallocated:
        case sd_uninit:
            return EINVAL;

        default:
            sd->flags |= VF_OPEN;                           /* note we're open */
            return 0;
        }

    case VINUM_SUPERDEV_TYPE:
        /* are we root? */
        error = caps_priv_check(ap->a_cred, SYSCAP_RESTRICTEDROOT);
        if (error == 0) {                                   /* yes, can do */
            if (devminor == VINUM_DAEMON_DEV)               /* daemon device */
                vinum_conf.flags |= VF_DAEMONOPEN;          /* we're open */
            else if (devminor == VINUM_SUPERDEV)
                vinum_conf.flags |= VF_OPEN;                /* we're open */
            else
                error = ENODEV;                             /* nothing, maybe a debug mismatch */
        }
        return error;

        /* Vinum drives are disks.  We already have a disk
         * driver, so don't handle them here */
    case VINUM_DRIVE_TYPE:
    default:
        return ENODEV;                                      /* don't know what to do with these */
    }
}

/* ARGSUSED */
int
vinumclose(struct dev_close_args *ap)
{
    cdev_t dev = ap->a_head.a_dev;
    unsigned int index;
    struct volume *vol;
    int devminor;

    devminor = minor(dev);
    index = Volno(dev);
    /* First, decide what we're looking at */
    switch (DEVTYPE(dev)) {
    case VINUM_VOLUME_TYPE:
        if (index >= vinum_conf.volumes_allocated)
            return ENXIO;                                   /* no such device */
        vol = &VOL[index];

        switch (vol->state) {
        case volume_unallocated:
        case volume_uninit:
            return ENXIO;

        case volume_up:
            vol->flags &= ~VF_OPEN;                         /* reset our flags */
            return 0;

        case volume_down:
            return EIO;

        default:
            return EINVAL;
        }

    case VINUM_PLEX_TYPE:
        if (Volno(dev) >= vinum_conf.volumes_allocated)
            return ENXIO;
        /* FALLTHROUGH */

    case VINUM_RAWPLEX_TYPE:
        index = Plexno(dev);                                /* get plex index in vinum_conf */
        if (index >= vinum_conf.plexes_allocated)
            return ENXIO;                                   /* no such device */
        PLEX[index].flags &= ~VF_OPEN;                      /* reset our flags */
        return 0;

    case VINUM_SD_TYPE:
        if ((Volno(dev) >= vinum_conf.volumes_allocated) || /* no such volume */
            (Plexno(dev) >= vinum_conf.plexes_allocated))   /* or no such plex */
            return ENXIO;                                   /* no such device */
        /* FALLTHROUGH */

    case VINUM_RAWSD_TYPE:
        index = Sdno(dev);                                  /* get the subdisk number */
        if (index >= vinum_conf.subdisks_allocated)
            return ENXIO;                                   /* no such device */
        SD[index].flags &= ~VF_OPEN;                        /* reset our flags */
        return 0;

    case VINUM_SUPERDEV_TYPE:
        /*
         * don't worry about whether we're root:
         * nobody else would get this far.
         */
        if (devminor == VINUM_SUPERDEV)                     /* normal superdev */
            vinum_conf.flags &= ~VF_OPEN;                   /* no longer open */
        else if (devminor == VINUM_DAEMON_DEV) {            /* the daemon device */
            vinum_conf.flags &= ~VF_DAEMONOPEN;             /* no longer open */
            if (vinum_conf.flags & VF_STOPPING)             /* we're stopping, */
                wakeup(&vinumclose);                        /* we can continue stopping now */
        }
        return 0;

    case VINUM_DRIVE_TYPE:
    default:
        return ENODEV;                                      /* don't know what to do with these */
    }
}

/* size routine */
int
vinumsize(struct dev_psize_args *ap)
{
    cdev_t dev = ap->a_head.a_dev;
    struct volume *vol;

    vol = &VOL[Volno(dev)];

    if (vol->state == volume_up) {
        ap->a_result = (int64_t)vol->size;
        return(0);
    } else {
        return(ENXIO);
    }
}

int
vinumdump(struct dev_dump_args *ap)
{
    /* Not implemented. */
    return ENXIO;
}

void
vinumfilt_detach(struct knote *kn) {}

int
vinumfilt_rd(struct knote *kn, long hint)
{
    cdev_t dev = (cdev_t)kn->kn_hook;

    if (seltrue(dev, POLLIN | POLLRDNORM))
        return (1);

    return (0);
}

int
vinumfilt_wr(struct knote *kn, long hint)
{
    /* Writing is always OK */
    return (1);
}

struct filterops vinumfiltops_rd =
    { FILTEROP_ISFD, NULL, vinumfilt_detach, vinumfilt_rd };
struct filterops vinumfiltops_wr =
    { FILTEROP_ISFD, NULL, vinumfilt_detach, vinumfilt_wr };

int
vinumkqfilter(struct dev_kqfilter_args *ap)
{
    if (ap->a_kn->kn_filter == EVFILT_READ) {
        ap->a_kn->kn_fop = &vinumfiltops_rd;
        ap->a_kn->kn_hook = (caddr_t)ap->a_head.a_dev;
        ap->a_result = 0;
    } else if (ap->a_kn->kn_filter == EVFILT_WRITE) {
        ap->a_kn->kn_fop = &vinumfiltops_wr;
        ap->a_result = 0;
    } else {
        ap->a_result = EOPNOTSUPP;
    }

    return (0);
}