/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2004-2006 Pawel Jakub Dawidek <pjd@FreeBSD.org>
 * All rights reserved.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``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 AUTHORS 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.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/bio.h>
#include <sys/sysctl.h>
#include <sys/malloc.h>
#include <sys/bitstring.h>
#include <vm/uma.h>
#include <machine/atomic.h>
#include <geom/geom.h>
#include <sys/proc.h>
#include <sys/kthread.h>
#include <geom/raid3/g_raid3.h>

static struct g_raid3_softc *
g_raid3_find_device(struct g_class *mp, const char *name)
{
        struct g_raid3_softc *sc;
        struct g_geom *gp;

        g_topology_lock();
        LIST_FOREACH(gp, &mp->geom, geom) {
                sc = gp->softc;
                if (sc == NULL)
                        continue;
                if ((sc->sc_flags & G_RAID3_DEVICE_FLAG_DESTROY) != 0)
                        continue;
                if (strcmp(gp->name, name) == 0 ||
                    strcmp(sc->sc_name, name) == 0) {
                        g_topology_unlock();
                        sx_xlock(&sc->sc_lock);
                        return (sc);
                }
        }
        g_topology_unlock();
        return (NULL);
}

static struct g_raid3_disk *
g_raid3_find_disk(struct g_raid3_softc *sc, const char *name)
{
        struct g_raid3_disk *disk;
        u_int n;

        sx_assert(&sc->sc_lock, SX_XLOCKED);
        if (strncmp(name, _PATH_DEV, 5) == 0)
                name += 5;
        for (n = 0; n < sc->sc_ndisks; n++) {
                disk = &sc->sc_disks[n];
                if (disk->d_state == G_RAID3_DISK_STATE_NODISK)
                        continue;
                if (disk->d_consumer == NULL)
                        continue;
                if (disk->d_consumer->provider == NULL)
                        continue;
                if (strcmp(disk->d_consumer->provider->name, name) == 0)
                        return (disk);
        }
        return (NULL);
}

static void
g_raid3_ctl_configure(struct gctl_req *req, struct g_class *mp)
{
        struct g_raid3_softc *sc;
        struct g_raid3_disk *disk;
        const char *name;
        int *nargs, do_sync = 0, dirty = 1;
        int *autosync, *noautosync;
        int *failsync, *nofailsync;
        int *round_robin, *noround_robin;
        int *verify, *noverify;
        u_int n;

        nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
        if (nargs == NULL) {
                gctl_error(req, "No '%s' argument.", "nargs");
                return;
        }
        if (*nargs != 1) {
                gctl_error(req, "Invalid number of arguments.");
                return;
        }
        autosync = gctl_get_paraml(req, "autosync", sizeof(*autosync));
        if (autosync == NULL) {
                gctl_error(req, "No '%s' argument.", "autosync");
                return;
        }
        noautosync = gctl_get_paraml(req, "noautosync", sizeof(*noautosync));
        if (noautosync == NULL) {
                gctl_error(req, "No '%s' argument.", "noautosync");
                return;
        }
        if (*autosync && *noautosync) {
                gctl_error(req, "'%s' and '%s' specified.", "autosync",
                    "noautosync");
                return;
        }
        failsync = gctl_get_paraml(req, "failsync", sizeof(*failsync));
        if (failsync == NULL) {
                gctl_error(req, "No '%s' argument.", "failsync");
                return;
        }
        nofailsync = gctl_get_paraml(req, "nofailsync", sizeof(*nofailsync));
        if (nofailsync == NULL) {
                gctl_error(req, "No '%s' argument.", "nofailsync");
                return;
        }
        if (*failsync && *nofailsync) {
                gctl_error(req, "'%s' and '%s' specified.", "failsync",
                    "nofailsync");
                return;
        }
        round_robin = gctl_get_paraml(req, "round_robin", sizeof(*round_robin));
        if (round_robin == NULL) {
                gctl_error(req, "No '%s' argument.", "round_robin");
                return;
        }
        noround_robin = gctl_get_paraml(req, "noround_robin",
            sizeof(*noround_robin));
        if (noround_robin == NULL) {
                gctl_error(req, "No '%s' argument.", "noround_robin");
                return;
        }
        if (*round_robin && *noround_robin) {
                gctl_error(req, "'%s' and '%s' specified.", "round_robin",
                    "noround_robin");
                return;
        }
        verify = gctl_get_paraml(req, "verify", sizeof(*verify));
        if (verify == NULL) {
                gctl_error(req, "No '%s' argument.", "verify");
                return;
        }
        noverify = gctl_get_paraml(req, "noverify", sizeof(*noverify));
        if (noverify == NULL) {
                gctl_error(req, "No '%s' argument.", "noverify");
                return;
        }
        if (*verify && *noverify) {
                gctl_error(req, "'%s' and '%s' specified.", "verify",
                    "noverify");
                return;
        }
        if (!*autosync && !*noautosync && !*failsync && !*nofailsync &&
            !*round_robin && !*noround_robin && !*verify && !*noverify) {
                gctl_error(req, "Nothing has changed.");
                return;
        }
        name = gctl_get_asciiparam(req, "arg0");
        if (name == NULL) {
                gctl_error(req, "No 'arg%u' argument.", 0);
                return;
        }
        sc = g_raid3_find_device(mp, name);
        if (sc == NULL) {
                gctl_error(req, "No such device: %s.", name);
                return;
        }
        if (g_raid3_ndisks(sc, -1) < sc->sc_ndisks) {
                gctl_error(req, "Not all disks connected.");
                sx_xunlock(&sc->sc_lock);
                return;
        }
        if ((sc->sc_flags & G_RAID3_DEVICE_FLAG_NOAUTOSYNC) != 0) {
                if (*autosync) {
                        sc->sc_flags &= ~G_RAID3_DEVICE_FLAG_NOAUTOSYNC;
                        do_sync = 1;
                }
        } else {
                if (*noautosync)
                        sc->sc_flags |= G_RAID3_DEVICE_FLAG_NOAUTOSYNC;
        }
        if ((sc->sc_flags & G_RAID3_DEVICE_FLAG_NOFAILSYNC) != 0) {
                if (*failsync)
                        sc->sc_flags &= ~G_RAID3_DEVICE_FLAG_NOFAILSYNC;
        } else {
                if (*nofailsync) {
                        sc->sc_flags |= G_RAID3_DEVICE_FLAG_NOFAILSYNC;
                        dirty = 0;
                }
        }
        if ((sc->sc_flags & G_RAID3_DEVICE_FLAG_VERIFY) != 0) {
                if (*noverify)
                        sc->sc_flags &= ~G_RAID3_DEVICE_FLAG_VERIFY;
        } else {
                if (*verify)
                        sc->sc_flags |= G_RAID3_DEVICE_FLAG_VERIFY;
        }
        if ((sc->sc_flags & G_RAID3_DEVICE_FLAG_ROUND_ROBIN) != 0) {
                if (*noround_robin)
                        sc->sc_flags &= ~G_RAID3_DEVICE_FLAG_ROUND_ROBIN;
        } else {
                if (*round_robin)
                        sc->sc_flags |= G_RAID3_DEVICE_FLAG_ROUND_ROBIN;
        }
        if ((sc->sc_flags & G_RAID3_DEVICE_FLAG_VERIFY) != 0 &&
            (sc->sc_flags & G_RAID3_DEVICE_FLAG_ROUND_ROBIN) != 0) {
                /*
                 * VERIFY and ROUND-ROBIN options are mutally exclusive.
                 */
                sc->sc_flags &= ~G_RAID3_DEVICE_FLAG_ROUND_ROBIN;
        }
        for (n = 0; n < sc->sc_ndisks; n++) {
                disk = &sc->sc_disks[n];
                if (do_sync) {
                        if (disk->d_state == G_RAID3_DISK_STATE_SYNCHRONIZING)
                                disk->d_flags &= ~G_RAID3_DISK_FLAG_FORCE_SYNC;
                }
                if (!dirty)
                        disk->d_flags &= ~G_RAID3_DISK_FLAG_DIRTY;
                g_raid3_update_metadata(disk);
                if (do_sync) {
                        if (disk->d_state == G_RAID3_DISK_STATE_STALE) {
                                /*
                                 * XXX: This is probably possible that this
                                 *      component will not be retasted.
                                 */
                                g_raid3_event_send(disk,
                                    G_RAID3_DISK_STATE_DISCONNECTED,
                                    G_RAID3_EVENT_DONTWAIT);
                        }
                }
        }
        sx_xunlock(&sc->sc_lock);
}

static void
g_raid3_ctl_rebuild(struct gctl_req *req, struct g_class *mp)
{
        struct g_raid3_metadata md;
        struct g_raid3_softc *sc;
        struct g_raid3_disk *disk;
        struct g_provider *pp;
        const char *name;
        int error, *nargs;

        nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
        if (nargs == NULL) {
                gctl_error(req, "No '%s' argument.", "nargs");
                return;
        }
        if (*nargs != 2) {
                gctl_error(req, "Invalid number of arguments.");
                return;
        }
        name = gctl_get_asciiparam(req, "arg0");
        if (name == NULL) {
                gctl_error(req, "No 'arg%u' argument.", 0);
                return;
        }
        sc = g_raid3_find_device(mp, name);
        if (sc == NULL) {
                gctl_error(req, "No such device: %s.", name);
                return;
        }
        name = gctl_get_asciiparam(req, "arg1");
        if (name == NULL) {
                gctl_error(req, "No 'arg%u' argument.", 1);
                sx_xunlock(&sc->sc_lock);
                return;
        }
        disk = g_raid3_find_disk(sc, name);
        if (disk == NULL) {
                gctl_error(req, "No such provider: %s.", name);
                sx_xunlock(&sc->sc_lock);
                return;
        }
        if (disk->d_state == G_RAID3_DISK_STATE_ACTIVE &&
            g_raid3_ndisks(sc, G_RAID3_DISK_STATE_ACTIVE) < sc->sc_ndisks) {
                gctl_error(req, "There is one stale disk already.");
                sx_xunlock(&sc->sc_lock);
                return;
        }
        /*
         * Do rebuild by resetting syncid and disconnecting disk.
         * It'll be retasted, connected to the device and synchronized.
         */
        disk->d_sync.ds_syncid = 0;
        if ((sc->sc_flags & G_RAID3_DEVICE_FLAG_NOAUTOSYNC) != 0)
                disk->d_flags |= G_RAID3_DISK_FLAG_FORCE_SYNC;
        g_raid3_update_metadata(disk);
        pp = disk->d_consumer->provider;
        g_topology_lock();
        error = g_raid3_read_metadata(disk->d_consumer, &md);
        g_topology_unlock();
        g_raid3_event_send(disk, G_RAID3_DISK_STATE_DISCONNECTED,
            G_RAID3_EVENT_WAIT);
        if (error != 0) {
                gctl_error(req, "Cannot read metadata from %s.", pp->name);
                sx_xunlock(&sc->sc_lock);
                return;
        }
        error = g_raid3_add_disk(sc, pp, &md);
        if (error != 0)
                gctl_error(req, "Cannot reconnect component %s.", pp->name);
        sx_xunlock(&sc->sc_lock);
}

static void
g_raid3_ctl_stop(struct gctl_req *req, struct g_class *mp)
{
        struct g_raid3_softc *sc;
        int *force, *nargs, error;
        const char *name;
        char param[16];
        u_int i;
        int how;

        nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
        if (nargs == NULL) {
                gctl_error(req, "No '%s' argument.", "nargs");
                return;
        }
        if (*nargs < 1) {
                gctl_error(req, "Missing device(s).");
                return;
        }
        force = gctl_get_paraml(req, "force", sizeof(*force));
        if (force == NULL) {
                gctl_error(req, "No '%s' argument.", "force");
                return;
        }
        if (*force)
                how = G_RAID3_DESTROY_HARD;
        else
                how = G_RAID3_DESTROY_SOFT;

        for (i = 0; i < (u_int)*nargs; i++) {
                snprintf(param, sizeof(param), "arg%u", i);
                name = gctl_get_asciiparam(req, param);
                if (name == NULL) {
                        gctl_error(req, "No 'arg%u' argument.", i);
                        return;
                }
                sc = g_raid3_find_device(mp, name);
                if (sc == NULL) {
                        gctl_error(req, "No such device: %s.", name);
                        return;
                }
                g_cancel_event(sc);
                error = g_raid3_destroy(sc, how);
                if (error != 0) {
                        gctl_error(req, "Cannot destroy device %s (error=%d).",
                            sc->sc_geom->name, error);
                        sx_xunlock(&sc->sc_lock);
                        return;
                }
                /* No need to unlock, because lock is already dead. */
        }
}

static void
g_raid3_ctl_insert_orphan(struct g_consumer *cp)
{

        KASSERT(1 == 0, ("%s called while inserting %s.", __func__,
            cp->provider->name));
}

static void
g_raid3_ctl_insert(struct gctl_req *req, struct g_class *mp)
{
        struct g_raid3_metadata md;
        struct g_raid3_softc *sc;
        struct g_raid3_disk *disk;
        struct g_geom *gp;
        struct g_provider *pp;
        struct g_consumer *cp;
        const char *name;
        u_char *sector;
        off_t compsize;
        intmax_t *no;
        int *hardcode, *nargs, error, autono;

        nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
        if (nargs == NULL) {
                gctl_error(req, "No '%s' argument.", "nargs");
                return;
        }
        if (*nargs != 2) {
                gctl_error(req, "Invalid number of arguments.");
                return;
        }
        hardcode = gctl_get_paraml(req, "hardcode", sizeof(*hardcode));
        if (hardcode == NULL) {
                gctl_error(req, "No '%s' argument.", "hardcode");
                return;
        }
        pp = gctl_get_provider(req, "arg1");
        if (pp == NULL)
                return;
        if (gctl_get_param(req, "number", NULL) != NULL)
                no = gctl_get_paraml(req, "number", sizeof(*no));
        else
                no = NULL;
        gp = g_new_geom(mp, "raid3:insert");
        gp->orphan = g_raid3_ctl_insert_orphan;
        cp = g_new_consumer(gp);
        error = g_attach(cp, pp);
        if (error != 0) {
                g_topology_unlock();
                gctl_error(req, "Cannot attach to %s.", pp->name);
                goto end;
        }
        error = g_access(cp, 0, 1, 1);
        if (error != 0) {
                g_topology_unlock();
                gctl_error(req, "Cannot access %s.", pp->name);
                goto end;
        }
        g_topology_unlock();
        name = gctl_get_asciiparam(req, "arg0");
        if (name == NULL) {
                gctl_error(req, "No 'arg%u' argument.", 0);
                goto end;
        }
        sc = g_raid3_find_device(mp, name);
        if (sc == NULL) {
                gctl_error(req, "No such device: %s.", name);
                goto end;
        }
        if (no != NULL) {
                if (*no < 0 || *no >= sc->sc_ndisks) {
                        sx_xunlock(&sc->sc_lock);
                        gctl_error(req, "Invalid component number.");
                        goto end;
                }
                disk = &sc->sc_disks[*no];
                if (disk->d_state != G_RAID3_DISK_STATE_NODISK) {
                        sx_xunlock(&sc->sc_lock);
                        gctl_error(req, "Component %jd is already connected.",
                            *no);
                        goto end;
                }
        } else {
                disk = NULL;
                for (autono = 0; autono < sc->sc_ndisks && disk == NULL; autono++)
                        if (sc->sc_disks[autono].d_state ==
                            G_RAID3_DISK_STATE_NODISK)
                                disk = &sc->sc_disks[autono];
                if (disk == NULL) {
                        sx_xunlock(&sc->sc_lock);
                        gctl_error(req, "No disconnected components.");
                        goto end;
                }
        }
        if (((sc->sc_sectorsize / (sc->sc_ndisks - 1)) % pp->sectorsize) != 0) {
                sx_xunlock(&sc->sc_lock);
                gctl_error(req,
                    "Cannot insert provider %s, because of its sector size.",
                    pp->name);
                goto end;
        }
        compsize = sc->sc_mediasize / (sc->sc_ndisks - 1);
        if (compsize > pp->mediasize - pp->sectorsize) {
                sx_xunlock(&sc->sc_lock);
                gctl_error(req, "Provider %s too small.", pp->name);
                goto end;
        }
        if (compsize < pp->mediasize - pp->sectorsize) {
                gctl_error(req,
                    "warning: %s: only %jd bytes from %jd bytes used.",
                    pp->name, (intmax_t)compsize,
                    (intmax_t)(pp->mediasize - pp->sectorsize));
        }
        g_raid3_fill_metadata(disk, &md);
        sx_xunlock(&sc->sc_lock);
        md.md_syncid = 0;
        md.md_dflags = 0;
        if (*hardcode)
                strlcpy(md.md_provider, pp->name, sizeof(md.md_provider));
        else
                bzero(md.md_provider, sizeof(md.md_provider));
        md.md_provsize = pp->mediasize;
        sector = g_malloc(pp->sectorsize, M_WAITOK);
        raid3_metadata_encode(&md, sector);
        error = g_write_data(cp, pp->mediasize - pp->sectorsize, sector,
            pp->sectorsize);
        g_free(sector);
        if (error != 0)
                gctl_error(req, "Cannot store metadata on %s.", pp->name);
end:
        g_topology_lock();
        if (cp->acw > 0)
                g_access(cp, 0, -1, -1);
        if (cp->provider != NULL)
                g_detach(cp);
        g_destroy_consumer(cp);
        g_destroy_geom(gp);
        g_topology_unlock();
}

static void
g_raid3_ctl_remove(struct gctl_req *req, struct g_class *mp)
{
        struct g_raid3_softc *sc;
        struct g_raid3_disk *disk;
        const char *name;
        intmax_t *no;
        int *nargs;

        nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
        if (nargs == NULL) {
                gctl_error(req, "No '%s' argument.", "nargs");
                return;
        }
        if (*nargs != 1) {
                gctl_error(req, "Invalid number of arguments.");
                return;
        }
        no = gctl_get_paraml(req, "number", sizeof(*no));
        if (no == NULL) {
                gctl_error(req, "No '%s' argument.", "no");
                return;
        }
        name = gctl_get_asciiparam(req, "arg0");
        if (name == NULL) {
                gctl_error(req, "No 'arg%u' argument.", 0);
                return;
        }
        sc = g_raid3_find_device(mp, name);
        if (sc == NULL) {
                gctl_error(req, "No such device: %s.", name);
                return;
        }
        if (*no >= sc->sc_ndisks) {
                sx_xunlock(&sc->sc_lock);
                gctl_error(req, "Invalid component number.");
                return;
        }
        disk = &sc->sc_disks[*no];
        switch (disk->d_state) {
        case G_RAID3_DISK_STATE_ACTIVE:
                /*
                 * When replacing ACTIVE component, all the rest has to be also
                 * ACTIVE.
                 */
                if (g_raid3_ndisks(sc, G_RAID3_DISK_STATE_ACTIVE) <
                    sc->sc_ndisks) {
                        gctl_error(req, "Cannot replace component number %jd.",
                            *no);
                        break;
                }
                /* FALLTHROUGH */
        case G_RAID3_DISK_STATE_STALE:
        case G_RAID3_DISK_STATE_SYNCHRONIZING:
                if (g_raid3_clear_metadata(disk) != 0) {
                        gctl_error(req, "Cannot clear metadata on %s.",
                            g_raid3_get_diskname(disk));
                } else {
                        g_raid3_event_send(disk,
                            G_RAID3_DISK_STATE_DISCONNECTED,
                            G_RAID3_EVENT_DONTWAIT);
                }
                break;
        case G_RAID3_DISK_STATE_NODISK:
                break;
        default:
                gctl_error(req, "Cannot replace component number %jd.", *no);
                break;
        }
        sx_xunlock(&sc->sc_lock);
}

void
g_raid3_config(struct gctl_req *req, struct g_class *mp, const char *verb)
{
        uint32_t *version;

        g_topology_assert();

        version = gctl_get_paraml(req, "version", sizeof(*version));
        if (version == NULL) {
                gctl_error(req, "No '%s' argument.", "version");
                return;
        }
        if (*version != G_RAID3_VERSION) {
                gctl_error(req, "Userland and kernel parts are out of sync.");
                return;
        }

        g_topology_unlock();
        if (strcmp(verb, "configure") == 0)
                g_raid3_ctl_configure(req, mp);
        else if (strcmp(verb, "insert") == 0)
                g_raid3_ctl_insert(req, mp);
        else if (strcmp(verb, "rebuild") == 0)
                g_raid3_ctl_rebuild(req, mp);
        else if (strcmp(verb, "remove") == 0)
                g_raid3_ctl_remove(req, mp);
        else if (strcmp(verb, "stop") == 0)
                g_raid3_ctl_stop(req, mp);
        else
                gctl_error(req, "Unknown verb.");
        g_topology_lock();
}