/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 2002 Poul-Henning Kamp
 * Copyright (c) 2002 Networks Associates Technology, Inc.
 * All rights reserved.
 *
 * This software was developed for the FreeBSD Project by Poul-Henning Kamp
 * and NAI Labs, the Security Research Division of Network Associates, Inc.
 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
 * DARPA CHATS research program.
 *
 * 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. The names of the authors may not be used to endorse or promote
 *    products derived from this software without specific prior written
 *    permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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/cdefs.h>
#include "opt_geom.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/bio.h>
#include <sys/ctype.h>
#include <sys/devctl.h>
#include <sys/fcntl.h>
#include <sys/malloc.h>
#include <sys/msan.h>
#include <sys/sbuf.h>
#include <sys/devicestat.h>

#include <sys/lock.h>
#include <sys/mutex.h>
#include <geom/geom.h>
#include <geom/geom_disk.h>
#include <geom/geom_int.h>

#include <dev/led/led.h>

#include <machine/bus.h>

struct g_disk_softc {
        struct disk             *dp;
        struct devstat          *d_devstat;
        struct sysctl_ctx_list  sysctl_ctx;
        struct sysctl_oid       *sysctl_tree;
        char                    led[64];
        uint32_t                state;
        struct mtx               done_mtx;
        bool                    flush_notsup_succeed;
};

static g_access_t g_disk_access;
static g_start_t g_disk_start;
static g_ioctl_t g_disk_ioctl;
static g_dumpconf_t g_disk_dumpconf;
static g_provgone_t g_disk_providergone;

static int g_disk_sysctl_flags(SYSCTL_HANDLER_ARGS);

static struct g_class g_disk_class = {
        .name = G_DISK_CLASS_NAME,
        .version = G_VERSION,
        .start = g_disk_start,
        .access = g_disk_access,
        .ioctl = g_disk_ioctl,
        .providergone = g_disk_providergone,
        .dumpconf = g_disk_dumpconf,
};

SYSCTL_DECL(_kern_geom);
static SYSCTL_NODE(_kern_geom, OID_AUTO, disk, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
    "GEOM_DISK stuff");

DECLARE_GEOM_CLASS(g_disk_class, g_disk);

static int
g_disk_access(struct g_provider *pp, int r, int w, int e)
{
        struct disk *dp;
        struct g_disk_softc *sc;
        int error;

        g_trace(G_T_ACCESS, "g_disk_access(%s, %d, %d, %d)",
            pp->name, r, w, e);
        g_topology_assert();
        sc = pp->private;
        if ((dp = sc->dp) == NULL || dp->d_destroyed) {
                /*
                 * Allow decreasing access count even if disk is not
                 * available anymore.
                 */
                if (r <= 0 && w <= 0 && e <= 0)
                        return (0);
                return (ENXIO);
        }
        r += pp->acr;
        w += pp->acw;
        e += pp->ace;
        error = 0;
        if ((pp->acr + pp->acw + pp->ace) == 0 && (r + w + e) > 0) {
                /*
                 * It would be better to defer this decision to d_open if
                 * it was able to take flags.
                 */
                if (w > 0 && (dp->d_flags & DISKFLAG_WRITE_PROTECT) != 0)
                        error = EROFS;
                if (error == 0 && dp->d_open != NULL)
                        error = dp->d_open(dp);
                if (bootverbose && error != 0)
                        printf("Opened disk %s -> %d\n", pp->name, error);
                if (error != 0)
                        return (error);
                pp->sectorsize = dp->d_sectorsize;
                if (dp->d_maxsize == 0) {
                        printf("WARNING: Disk drive %s%d has no d_maxsize\n",
                            dp->d_name, dp->d_unit);
                        dp->d_maxsize = DFLTPHYS;
                }
                if (dp->d_delmaxsize == 0) {
                        if (bootverbose && dp->d_flags & DISKFLAG_CANDELETE) {
                                printf("WARNING: Disk drive %s%d has no "
                                    "d_delmaxsize\n", dp->d_name, dp->d_unit);
                        }
                        dp->d_delmaxsize = dp->d_maxsize;
                }
                pp->stripeoffset = dp->d_stripeoffset;
                pp->stripesize = dp->d_stripesize;
                dp->d_flags |= DISKFLAG_OPEN;
                /*
                 * Do not invoke resize event when initial size was zero.
                 * Some disks report its size only after first opening.
                 */
                if (pp->mediasize == 0)
                        pp->mediasize = dp->d_mediasize;
                else
                        g_resize_provider(pp, dp->d_mediasize);
        } else if ((pp->acr + pp->acw + pp->ace) > 0 && (r + w + e) == 0) {
                if (dp->d_close != NULL) {
                        error = dp->d_close(dp);
                        if (error != 0)
                                printf("Closed disk %s -> %d\n",
                                    pp->name, error);
                }
                sc->state = G_STATE_ACTIVE;
                if (sc->led[0] != 0)
                        led_set(sc->led, "0");
                dp->d_flags &= ~DISKFLAG_OPEN;
        }
        return (error);
}

static void
g_disk_kerneldump(struct bio *bp, struct disk *dp)
{
        struct g_kerneldump *gkd;
        struct g_geom *gp;

        gkd = (struct g_kerneldump*)bp->bio_data;
        gp = bp->bio_to->geom;
        g_trace(G_T_TOPOLOGY, "g_disk_kerneldump(%s, %jd, %jd)",
                gp->name, (intmax_t)gkd->offset, (intmax_t)gkd->length);
        if (dp->d_dump == NULL) {
                g_io_deliver(bp, ENODEV);
                return;
        }
        gkd->di.dumper = dp->d_dump;
        gkd->di.priv = dp;
        gkd->di.blocksize = dp->d_sectorsize;
        gkd->di.maxiosize = dp->d_maxsize;
        gkd->di.mediaoffset = gkd->offset;
        if ((gkd->offset + gkd->length) > dp->d_mediasize)
                gkd->length = dp->d_mediasize - gkd->offset;
        gkd->di.mediasize = gkd->length;
        g_io_deliver(bp, 0);
}

static void
g_disk_setstate(struct bio *bp, struct g_disk_softc *sc)
{
        const char *cmd;

        memcpy(&sc->state, bp->bio_data, sizeof(sc->state));
        if (sc->led[0] != 0) {
                switch (sc->state) {
                case G_STATE_FAILED:
                        cmd = "1";
                        break;
                case G_STATE_REBUILD:
                        cmd = "f5";
                        break;
                case G_STATE_RESYNC:
                        cmd = "f1";
                        break;
                default:
                        cmd = "0";
                        break;
                }
                led_set(sc->led, cmd);
        }
        g_io_deliver(bp, 0);
}

static void
g_disk_done(struct bio *bp)
{
        struct bintime now;
        struct bio *bp2;
        struct g_disk_softc *sc;

        /* See "notes" for why we need a mutex here */
        sc = bp->bio_caller1;
        bp2 = bp->bio_parent;
        binuptime(&now);
        mtx_lock(&sc->done_mtx);
        if (bp2->bio_error == 0) {
                if ((bp->bio_flags & BIO_EXTERR) != 0) {
                        bp2->bio_flags |= BIO_EXTERR;
                        bp2->bio_exterr = bp->bio_exterr;
                } else {
                        bp2->bio_error = bp->bio_error;
                }
        }
        bp2->bio_completed += bp->bio_length - bp->bio_resid;

        if (bp->bio_cmd == BIO_READ)
                kmsan_check(bp2->bio_data, bp2->bio_completed, "g_disk_done");

        switch (bp->bio_cmd) {
        case BIO_ZONE:
                bcopy(&bp->bio_zone, &bp2->bio_zone, sizeof(bp->bio_zone));
                /*FALLTHROUGH*/
        case BIO_READ:
        case BIO_WRITE:
        case BIO_DELETE:
        case BIO_FLUSH:
                devstat_end_transaction_bio_bt(sc->d_devstat, bp, &now);
                break;
        default:
                break;
        }
        bp2->bio_inbed++;
        if (bp2->bio_children == bp2->bio_inbed) {
                mtx_unlock(&sc->done_mtx);
                bp2->bio_resid = bp2->bio_bcount - bp2->bio_completed;
                g_io_deliver(bp2, bp2->bio_error);
        } else
                mtx_unlock(&sc->done_mtx);
        g_destroy_bio(bp);
}

static int
g_disk_ioctl(struct g_provider *pp, u_long cmd, void * data, int fflag, struct thread *td)
{
        struct disk *dp;
        struct g_disk_softc *sc;

        sc = pp->private;
        dp = sc->dp;
        KASSERT(dp != NULL && !dp->d_destroyed,
            ("g_disk_ioctl(%lx) on destroyed disk %s", cmd, pp->name));

        if (dp->d_ioctl == NULL)
                return (ENOIOCTL);
        return (dp->d_ioctl(dp, cmd, data, fflag, td));
}

static off_t
g_disk_maxsize(struct disk *dp, struct bio *bp)
{
        if (bp->bio_cmd == BIO_DELETE)
                return (dp->d_delmaxsize);
        return (dp->d_maxsize);
}

static int
g_disk_maxsegs(struct disk *dp, struct bio *bp)
{
        return ((g_disk_maxsize(dp, bp) / PAGE_SIZE) + 1);
}

static void
g_disk_advance(struct disk *dp, struct bio *bp, off_t off)
{

        bp->bio_offset += off;
        bp->bio_length -= off;

        if ((bp->bio_flags & BIO_VLIST) != 0) {
                bus_dma_segment_t *seg, *end;

                seg = (bus_dma_segment_t *)bp->bio_data;
                end = (bus_dma_segment_t *)bp->bio_data + bp->bio_ma_n;
                off += bp->bio_ma_offset;
                while (off >= seg->ds_len) {
                        KASSERT((seg != end),
                            ("vlist request runs off the end"));
                        off -= seg->ds_len;
                        seg++;
                }
                bp->bio_ma_offset = off;
                bp->bio_ma_n = end - seg;
                bp->bio_data = (void *)seg;
        } else if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
                bp->bio_ma += off / PAGE_SIZE;
                bp->bio_ma_offset += off;
                bp->bio_ma_offset %= PAGE_SIZE;
                bp->bio_ma_n -= off / PAGE_SIZE;
        } else {
                bp->bio_data += off;
        }
}

static void
g_disk_seg_limit(bus_dma_segment_t *seg, off_t *poffset,
    off_t *plength, int *ppages)
{
        uintptr_t seg_page_base;
        uintptr_t seg_page_end;
        off_t offset;
        off_t length;
        int seg_pages;

        offset = *poffset;
        length = *plength;

        if (length > seg->ds_len - offset)
                length = seg->ds_len - offset;

        seg_page_base = trunc_page(seg->ds_addr + offset);
        seg_page_end  = round_page(seg->ds_addr + offset + length);
        seg_pages = (seg_page_end - seg_page_base) >> PAGE_SHIFT;

        if (seg_pages > *ppages) {
                seg_pages = *ppages;
                length = (seg_page_base + (seg_pages << PAGE_SHIFT)) -
                    (seg->ds_addr + offset);
        }

        *poffset = 0;
        *plength -= length;
        *ppages -= seg_pages;
}

static off_t
g_disk_vlist_limit(struct disk *dp, struct bio *bp, bus_dma_segment_t **pendseg)
{
        bus_dma_segment_t *seg, *end __diagused;
        off_t residual;
        off_t offset;
        int pages;

        seg = (bus_dma_segment_t *)bp->bio_data;
        end = (bus_dma_segment_t *)bp->bio_data + bp->bio_ma_n;
        residual = bp->bio_length;
        offset = bp->bio_ma_offset;
        pages = g_disk_maxsegs(dp, bp);
        while (residual != 0 && pages != 0) {
                KASSERT((seg != end),
                    ("vlist limit runs off the end"));
                g_disk_seg_limit(seg, &offset, &residual, &pages);
                seg++;
        }
        if (pendseg != NULL)
                *pendseg = seg;
        return (residual);
}

static bool
g_disk_limit(struct disk *dp, struct bio *bp)
{
        bool limited = false;
        off_t maxsz;

        maxsz = g_disk_maxsize(dp, bp);

        /*
         * XXX: If we have a stripesize we should really use it here.
         *      Care should be taken in the delete case if this is done
         *      as deletes can be very sensitive to size given how they
         *      are processed.
         */
        if (bp->bio_length > maxsz) {
                bp->bio_length = maxsz;
                limited = true;
        }

        if ((bp->bio_flags & BIO_VLIST) != 0) {
                bus_dma_segment_t *firstseg, *endseg;
                off_t residual;

                firstseg = (bus_dma_segment_t*)bp->bio_data;
                residual = g_disk_vlist_limit(dp, bp, &endseg);
                if (residual != 0) {
                        bp->bio_ma_n = endseg - firstseg;
                        bp->bio_length -= residual;
                        limited = true;
                }
        } else if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
                bp->bio_ma_n =
                    howmany(bp->bio_ma_offset + bp->bio_length, PAGE_SIZE);
        }

        return (limited);
}

static void
g_disk_start(struct bio *bp)
{
        struct bio *bp2, *bp3;
        struct disk *dp;
        struct g_disk_softc *sc;
        int error;
        off_t off;

        biotrack(bp, __func__);

        sc = bp->bio_to->private;
        dp = sc->dp;
        KASSERT(dp != NULL && !dp->d_destroyed,
            ("g_disk_start(%p) on destroyed disk %s", bp, bp->bio_to->name));
        error = EJUSTRETURN;
        switch(bp->bio_cmd) {
        case BIO_DELETE:
                if (!(dp->d_flags & DISKFLAG_CANDELETE)) {
                        error = EOPNOTSUPP;
                        break;
                }
                /* fall-through */
        case BIO_READ:
        case BIO_WRITE:
                KASSERT((dp->d_flags & DISKFLAG_UNMAPPED_BIO) != 0 ||
                    (bp->bio_flags & BIO_UNMAPPED) == 0,
                    ("unmapped bio not supported by disk %s", dp->d_name));

                if (bp->bio_cmd == BIO_WRITE)
                        kmsan_check_bio(bp, "g_disk_start");

                off = 0;
                bp3 = NULL;
                bp2 = g_clone_bio(bp);
                if (bp2 == NULL) {
                        error = ENOMEM;
                        break;
                }
                for (;;) {
                        if (g_disk_limit(dp, bp2)) {
                                off += bp2->bio_length;

                                /*
                                 * To avoid a race, we need to grab the next bio
                                 * before we schedule this one.  See "notes".
                                 */
                                bp3 = g_clone_bio(bp);
                                if (bp3 == NULL)
                                        bp->bio_error = ENOMEM;
                        }
                        bp2->bio_done = g_disk_done;
                        bp2->bio_caller1 = sc;
                        bp2->bio_pblkno = bp2->bio_offset / dp->d_sectorsize;
                        bp2->bio_bcount = bp2->bio_length;
                        bp2->bio_disk = dp;
                        devstat_start_transaction_bio(dp->d_devstat, bp2);
                        dp->d_strategy(bp2);

                        if (bp3 == NULL)
                                break;

                        bp2 = bp3;
                        bp3 = NULL;
                        g_disk_advance(dp, bp2, off);
                }
                break;
        case BIO_GETATTR:
                /* Give the driver a chance to override */
                if (dp->d_getattr != NULL) {
                        if (bp->bio_disk == NULL)
                                bp->bio_disk = dp;
                        error = dp->d_getattr(bp);
                        if (error != -1)
                                break;
                        error = EJUSTRETURN;
                }
                if (g_handleattr_int(bp, "GEOM::candelete",
                    (dp->d_flags & DISKFLAG_CANDELETE) != 0))
                        break;
                else if (g_handleattr_int(bp, "GEOM::fwsectors",
                    dp->d_fwsectors))
                        break;
                else if (g_handleattr_int(bp, "GEOM::fwheads", dp->d_fwheads))
                        break;
                else if (g_handleattr_str(bp, "GEOM::ident", dp->d_ident))
                        break;
                else if (g_handleattr_str(bp, "GEOM::descr", dp->d_descr))
                        break;
                else if (g_handleattr_uint16_t(bp, "GEOM::hba_vendor",
                    dp->d_hba_vendor))
                        break;
                else if (g_handleattr_uint16_t(bp, "GEOM::hba_device",
                    dp->d_hba_device))
                        break;
                else if (g_handleattr_uint16_t(bp, "GEOM::hba_subvendor",
                    dp->d_hba_subvendor))
                        break;
                else if (g_handleattr_uint16_t(bp, "GEOM::hba_subdevice",
                    dp->d_hba_subdevice))
                        break;
                else if (!strcmp(bp->bio_attribute, "GEOM::kerneldump"))
                        g_disk_kerneldump(bp, dp);
                else if (!strcmp(bp->bio_attribute, "GEOM::setstate"))
                        g_disk_setstate(bp, sc);
                else if (g_handleattr_uint16_t(bp, "GEOM::rotation_rate",
                    dp->d_rotation_rate))
                        break;
                else if (g_handleattr_str(bp, "GEOM::attachment",
                    dp->d_attachment))
                        break;
                else
                        error = ENOIOCTL;
                break;
        case BIO_FLUSH:
                g_trace(G_T_BIO, "g_disk_flushcache(%s)",
                    bp->bio_to->name);
                if (!(dp->d_flags & DISKFLAG_CANFLUSHCACHE)) {
                        error = (sc->flush_notsup_succeed) ? 0 : EOPNOTSUPP;
                        break;
                }
                /*FALLTHROUGH*/
        case BIO_ZONE:
                if (bp->bio_cmd == BIO_ZONE) {
                        if (!(dp->d_flags & DISKFLAG_CANZONE)) {
                                error = EOPNOTSUPP;
                                break;
                        }
                        g_trace(G_T_BIO, "g_disk_zone(%s)",
                            bp->bio_to->name);
                }
                bp2 = g_clone_bio(bp);
                if (bp2 == NULL) {
                        g_io_deliver(bp, ENOMEM);
                        return;
                }
                bp2->bio_done = g_disk_done;
                bp2->bio_caller1 = sc;
                bp2->bio_disk = dp;
                devstat_start_transaction_bio(dp->d_devstat, bp2);
                dp->d_strategy(bp2);
                break;
        case BIO_SPEEDUP:
                bp2 = g_clone_bio(bp);
                if (bp2 == NULL) {
                        g_io_deliver(bp, ENOMEM);
                        return;
                }
                bp2->bio_done = g_disk_done;
                bp2->bio_caller1 = sc;
                bp2->bio_disk = dp;
                dp->d_strategy(bp2);
                break;
        default:
                error = EOPNOTSUPP;
                break;
        }
        if (error != EJUSTRETURN)
                g_io_deliver(bp, error);
        return;
}

static void
g_disk_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
{
        struct bio *bp;
        struct disk *dp;
        struct g_disk_softc *sc;
        char *buf;
        int res = 0;

        sc = gp->softc;
        if (sc == NULL || (dp = sc->dp) == NULL)
                return;
        if (indent == NULL) {
                sbuf_printf(sb, " hd %u", dp->d_fwheads);
                sbuf_printf(sb, " sc %u", dp->d_fwsectors);
                return;
        }
        if (pp != NULL) {
                sbuf_printf(sb, "%s<fwheads>%u</fwheads>\n",
                    indent, dp->d_fwheads);
                sbuf_printf(sb, "%s<fwsectors>%u</fwsectors>\n",
                    indent, dp->d_fwsectors);

                /*
                 * "rotationrate" is a little complicated, because the value
                 * returned by the drive might not be the RPM; 0 and 1 are
                 * special cases, and there's also a valid range.
                 */
                sbuf_printf(sb, "%s<rotationrate>", indent);
                if (dp->d_rotation_rate == DISK_RR_UNKNOWN) /* Old drives */
                        sbuf_cat(sb, "unknown");        /* don't report RPM. */
                else if (dp->d_rotation_rate == DISK_RR_NON_ROTATING)
                        sbuf_cat(sb, "0");
                else if ((dp->d_rotation_rate >= DISK_RR_MIN) &&
                    (dp->d_rotation_rate <= DISK_RR_MAX))
                        sbuf_printf(sb, "%u", dp->d_rotation_rate);
                else
                        sbuf_cat(sb, "invalid");
                sbuf_cat(sb, "</rotationrate>\n");
                if (dp->d_getattr != NULL) {
                        buf = g_malloc(DISK_IDENT_SIZE, M_WAITOK);
                        bp = g_alloc_bio();
                        bp->bio_disk = dp;
                        bp->bio_attribute = "GEOM::ident";
                        bp->bio_length = DISK_IDENT_SIZE;
                        bp->bio_data = buf;
                        res = dp->d_getattr(bp);
                        sbuf_printf(sb, "%s<ident>", indent);
                        g_conf_cat_escaped(sb, res == 0 ? buf : dp->d_ident);
                        sbuf_cat(sb, "</ident>\n");
                        bp->bio_attribute = "GEOM::lunid";
                        bp->bio_length = DISK_IDENT_SIZE;
                        bp->bio_data = buf;
                        if (dp->d_getattr(bp) == 0) {
                                sbuf_printf(sb, "%s<lunid>", indent);
                                g_conf_cat_escaped(sb, buf);
                                sbuf_cat(sb, "</lunid>\n");
                        }
                        bp->bio_attribute = "GEOM::lunname";
                        bp->bio_length = DISK_IDENT_SIZE;
                        bp->bio_data = buf;
                        if (dp->d_getattr(bp) == 0) {
                                sbuf_printf(sb, "%s<lunname>", indent);
                                g_conf_cat_escaped(sb, buf);
                                sbuf_cat(sb, "</lunname>\n");
                        }
                        g_destroy_bio(bp);
                        g_free(buf);
                } else {
                        sbuf_printf(sb, "%s<ident>", indent);
                        g_conf_cat_escaped(sb, dp->d_ident);
                        sbuf_cat(sb, "</ident>\n");
                }
                sbuf_printf(sb, "%s<descr>", indent);
                g_conf_cat_escaped(sb, dp->d_descr);
                sbuf_cat(sb, "</descr>\n");
        }
}

static void
g_disk_resize(void *ptr, int flag)
{
        struct disk *dp;
        struct g_geom *gp;
        struct g_provider *pp;

        if (flag == EV_CANCEL)
                return;
        g_topology_assert();

        dp = ptr;
        gp = dp->d_geom;

        if (dp->d_destroyed || gp == NULL)
                return;

        LIST_FOREACH(pp, &gp->provider, provider) {
                if (pp->sectorsize != 0 &&
                    pp->sectorsize != dp->d_sectorsize)
                        g_wither_provider(pp, ENXIO);
                else
                        g_resize_provider(pp, dp->d_mediasize);
        }
}

static void
g_disk_create(void *arg, int flag)
{
        struct g_geom *gp;
        struct g_provider *pp;
        struct disk *dp;
        struct g_disk_softc *sc;
        struct disk_alias *dap;
        char tmpstr[80];

        if (flag == EV_CANCEL)
                return;
        g_topology_assert();
        dp = arg;

        mtx_pool_lock(mtxpool_sleep, dp);
        dp->d_init_level = DISK_INIT_START;

        /*
         * If the disk has already gone away, we can just stop here and
         * call the user's callback to tell him we've cleaned things up.
         */
        if (dp->d_goneflag != 0) {
                mtx_pool_unlock(mtxpool_sleep, dp);
                if (dp->d_gone != NULL)
                        dp->d_gone(dp);
                return;
        }
        mtx_pool_unlock(mtxpool_sleep, dp);

        sc = g_malloc(sizeof(*sc), M_WAITOK | M_ZERO);
        mtx_init(&sc->done_mtx, "g_disk_done", NULL, MTX_DEF);
        sc->dp = dp;
        if (dp->d_devstat == NULL) {
                dp->d_devstat = devstat_new_entry(dp->d_name, dp->d_unit,
                    dp->d_sectorsize, DEVSTAT_ALL_SUPPORTED,
                    DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
        }
        sc->d_devstat = dp->d_devstat;
        gp = g_new_geomf(&g_disk_class, "%s%d", dp->d_name, dp->d_unit);
        gp->softc = sc;
        pp = g_new_providerf(gp, "%s", gp->name);
        LIST_FOREACH(dap, &dp->d_aliases, da_next)
                g_provider_add_alias(pp, "%s%d", dap->da_alias, dp->d_unit);
        devstat_remove_entry(pp->stat);
        pp->stat = NULL;
        dp->d_devstat->id = pp;
        pp->mediasize = dp->d_mediasize;
        pp->sectorsize = dp->d_sectorsize;
        pp->stripeoffset = dp->d_stripeoffset;
        pp->stripesize = dp->d_stripesize;
        if ((dp->d_flags & DISKFLAG_UNMAPPED_BIO) != 0)
                pp->flags |= G_PF_ACCEPT_UNMAPPED;
        if ((dp->d_flags & DISKFLAG_DIRECT_COMPLETION) != 0)
                pp->flags |= G_PF_DIRECT_SEND;
        pp->flags |= G_PF_DIRECT_RECEIVE;
        if (bootverbose)
                printf("GEOM: new disk %s\n", gp->name);
        sysctl_ctx_init(&sc->sysctl_ctx);
        snprintf(tmpstr, sizeof(tmpstr), "GEOM disk %s", gp->name);
        sc->sysctl_tree = SYSCTL_ADD_NODE(&sc->sysctl_ctx,
                SYSCTL_STATIC_CHILDREN(_kern_geom_disk), OID_AUTO, gp->name,
                CTLFLAG_RD | CTLFLAG_MPSAFE, 0, tmpstr);
        if (sc->sysctl_tree != NULL) {
                SYSCTL_ADD_STRING(&sc->sysctl_ctx,
                    SYSCTL_CHILDREN(sc->sysctl_tree), OID_AUTO, "led",
                    CTLFLAG_RWTUN, sc->led, sizeof(sc->led),
                    "LED name");
                SYSCTL_ADD_PROC(&sc->sysctl_ctx,
                    SYSCTL_CHILDREN(sc->sysctl_tree), OID_AUTO, "flags",
                    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, dp, 0,
                    g_disk_sysctl_flags, "A", "Report disk flags");
                SYSCTL_ADD_BOOL(&sc->sysctl_ctx,
                    SYSCTL_CHILDREN(sc->sysctl_tree), OID_AUTO, "flush_notsup_succeed",
                    CTLFLAG_RWTUN, &sc->flush_notsup_succeed, sizeof(sc->flush_notsup_succeed),
                    "Do not return EOPNOTSUPP if there is no cache to flush");
        }
        pp->private = sc;
        dp->d_geom = gp;
        g_error_provider(pp, 0);

        mtx_pool_lock(mtxpool_sleep, dp);
        dp->d_init_level = DISK_INIT_DONE;

        /*
         * If the disk has gone away at this stage, start the withering
         * process for it.
         */
        if (dp->d_goneflag != 0) {
                mtx_pool_unlock(mtxpool_sleep, dp);
                g_wither_provider(pp, ENXIO);
                return;
        }
        mtx_pool_unlock(mtxpool_sleep, dp);

}

/*
 * We get this callback after all of the consumers have gone away, and just
 * before the provider is freed.  If the disk driver provided a d_gone
 * callback, let them know that it is okay to free resources -- they won't
 * be getting any more accesses from GEOM.
 */
static void
g_disk_providergone(struct g_provider *pp)
{
        struct disk *dp;
        struct g_disk_softc *sc;

        sc = (struct g_disk_softc *)pp->private;
        dp = sc->dp;
        if (dp != NULL && dp->d_gone != NULL)
                dp->d_gone(dp);
        if (sc->sysctl_tree != NULL) {
                sysctl_ctx_free(&sc->sysctl_ctx);
                sc->sysctl_tree = NULL;
        }
        if (sc->led[0] != 0) {
                led_set(sc->led, "0");
                sc->led[0] = 0;
        }
        pp->private = NULL;
        pp->geom->softc = NULL;
        mtx_destroy(&sc->done_mtx);
        g_free(sc);
}

static void
g_disk_destroy(void *ptr, int flag)
{
        struct disk *dp;
        struct g_geom *gp;
        struct g_disk_softc *sc;
        struct disk_alias *dap, *daptmp;

        g_topology_assert();
        dp = ptr;
        gp = dp->d_geom;
        if (gp != NULL) {
                sc = gp->softc;
                if (sc != NULL)
                        sc->dp = NULL;
                dp->d_geom = NULL;
                g_wither_geom(gp, ENXIO);
        }
        LIST_FOREACH_SAFE(dap, &dp->d_aliases, da_next, daptmp)
                g_free(dap);

        g_free(dp);
}

/*
 * We only allow printable characters in disk ident,
 * the rest is converted to 'x<HH>'.
 */
static void
g_disk_ident_adjust(char *ident, size_t size)
{
        char *p, tmp[4], newid[DISK_IDENT_SIZE];

        newid[0] = '\0';
        for (p = ident; *p != '\0'; p++) {
                if (isprint(*p)) {
                        tmp[0] = *p;
                        tmp[1] = '\0';
                } else {
                        snprintf(tmp, sizeof(tmp), "x%02hhx",
                            *(unsigned char *)p);
                }
                if (strlcat(newid, tmp, sizeof(newid)) >= sizeof(newid))
                        break;
        }
        bzero(ident, size);
        strlcpy(ident, newid, size);
}

struct disk *
disk_alloc(void)
{
        struct disk *dp;

        dp = g_malloc(sizeof(struct disk), M_WAITOK | M_ZERO);
        LIST_INIT(&dp->d_aliases);
        dp->d_init_level = DISK_INIT_NONE;
        dp->d_cevent = g_alloc_event(M_WAITOK);
        dp->d_devent = g_alloc_event(M_WAITOK);
        return (dp);
}

void
disk_create(struct disk *dp, int version)
{

        if (version != DISK_VERSION) {
                printf("WARNING: Attempt to add disk %s%d %s",
                    dp->d_name, dp->d_unit,
                    " using incompatible ABI version of disk(9)\n");
                printf("WARNING: Ignoring disk %s%d\n",
                    dp->d_name, dp->d_unit);
                return;
        }
        if (dp->d_flags & DISKFLAG_RESERVED) {
                printf("WARNING: Attempt to add non-MPSAFE disk %s%d\n",
                    dp->d_name, dp->d_unit);
                printf("WARNING: Ignoring disk %s%d\n",
                    dp->d_name, dp->d_unit);
                return;
        }
        KASSERT(dp->d_strategy != NULL, ("disk_create need d_strategy"));
        KASSERT(dp->d_name != NULL, ("disk_create need d_name"));
        KASSERT(*dp->d_name != 0, ("disk_create need d_name"));
        KASSERT(strlen(dp->d_name) < SPECNAMELEN - 4, ("disk name too long"));
        g_disk_ident_adjust(dp->d_ident, sizeof(dp->d_ident));

        dp->d_init_level = DISK_INIT_CREATE;

        KASSERT(dp->d_cevent != NULL,
            ("Disk create for %p with event NULL", dp));
        g_post_event_ep(g_disk_create, dp, dp->d_cevent, dp, NULL);
}

void
disk_destroy(struct disk *dp)
{
        struct disk_alias *dap, *daptmp;

        /* If disk_create() was never called, just free the resources. */
        if (dp->d_init_level < DISK_INIT_CREATE) {
                if (dp->d_devstat != NULL)
                        devstat_remove_entry(dp->d_devstat);
                LIST_FOREACH_SAFE(dap, &dp->d_aliases, da_next, daptmp)
                        g_free(dap);
                g_free(dp->d_cevent);
                g_free(dp->d_devent);
                g_free(dp);
                return;
        }

        KASSERT(dp->d_devent != NULL,
            ("Disk destroy for %p with event NULL", dp));
        disk_gone(dp);
        dp->d_destroyed = 1;
        g_cancel_event(dp);
        if (dp->d_devstat != NULL)
                devstat_remove_entry(dp->d_devstat);
        g_post_event_ep(g_disk_destroy, dp, dp->d_devent, NULL);
}

void
disk_add_alias(struct disk *dp, const char *name)
{
        struct disk_alias *dap;

        dap = (struct disk_alias *)g_malloc(
                sizeof(struct disk_alias) + strlen(name) + 1, M_WAITOK);
        strcpy((char *)(dap + 1), name);
        dap->da_alias = (const char *)(dap + 1);
        LIST_INSERT_HEAD(&dp->d_aliases, dap, da_next);
}

void
disk_gone(struct disk *dp)
{
        struct g_geom *gp;
        struct g_provider *pp;

        mtx_pool_lock(mtxpool_sleep, dp);

        /*
         * Second wither call makes no sense, plus we can not access the list
         * of providers without topology lock after calling wither once.
         */
        if (dp->d_goneflag != 0) {
                mtx_pool_unlock(mtxpool_sleep, dp);
                return;
        }

        dp->d_goneflag = 1;

        /*
         * If we're still in the process of creating this disk (the
         * g_disk_create() function is still queued, or is in
         * progress), the init level will not yet be DISK_INIT_DONE.
         *
         * If that is the case, g_disk_create() will see d_goneflag
         * and take care of cleaning things up.
         *
         * If the disk has already been created, we default to
         * withering the provider as usual below.
         *
         * If the caller has not set a d_gone() callback, he will
         * not be any worse off by returning here, because the geom
         * has not been fully setup in any case.
         */
        if (dp->d_init_level < DISK_INIT_DONE) {
                mtx_pool_unlock(mtxpool_sleep, dp);
                return;
        }
        mtx_pool_unlock(mtxpool_sleep, dp);

        gp = dp->d_geom;
        pp = LIST_FIRST(&gp->provider);
        if (pp != NULL) {
                KASSERT(LIST_NEXT(pp, provider) == NULL,
                    ("geom %p has more than one provider", gp));
                g_wither_provider(pp, ENXIO);
        }
}

void
disk_attr_changed(struct disk *dp, const char *attr, int flag)
{
        struct g_geom *gp = dp->d_geom;
        struct g_provider *pp;
        char devnamebuf[128];

        if (gp == NULL)
                return;
        LIST_FOREACH(pp, &gp->provider, provider)
                (void)g_attr_changed(pp, attr, flag);
        snprintf(devnamebuf, sizeof(devnamebuf), "devname=%s%d", dp->d_name,
            dp->d_unit);
        devctl_notify("GEOM", "disk", attr, devnamebuf);
}

void
disk_media_changed(struct disk *dp, int flag)
{
        struct g_geom *gp = dp->d_geom;
        struct g_provider *pp;

        if (gp == NULL)
                return;
        pp = LIST_FIRST(&gp->provider);
        if (pp != NULL) {
                KASSERT(LIST_NEXT(pp, provider) == NULL,
                    ("geom %p has more than one provider", gp));
                g_media_changed(pp, flag);
        }
}

void
disk_media_gone(struct disk *dp, int flag)
{
        struct g_geom *gp = dp->d_geom;
        struct g_provider *pp;

        if (gp == NULL)
                return;
        pp = LIST_FIRST(&gp->provider);
        if (pp != NULL) {
                KASSERT(LIST_NEXT(pp, provider) == NULL,
                    ("geom %p has more than one provider", gp));
                g_media_gone(pp, flag);
        }
}

int
disk_resize(struct disk *dp, int flag)
{

        if (dp->d_destroyed || dp->d_geom == NULL)
                return (0);

        return (g_post_event(g_disk_resize, dp, flag, NULL));
}

static void
g_kern_disks(void *p, int flag __unused)
{
        struct sbuf *sb;
        struct g_geom *gp;
        char *sp;

        sb = p;
        sp = "";
        g_topology_assert();
        LIST_FOREACH(gp, &g_disk_class.geom, geom) {
                sbuf_printf(sb, "%s%s", sp, gp->name);
                sp = " ";
        }
        sbuf_finish(sb);
}

static int
g_disk_sysctl_flags(SYSCTL_HANDLER_ARGS)
{
        struct disk *dp;
        struct sbuf *sb;
        int error;

        sb = sbuf_new_auto();
        dp = (struct disk *)arg1;
        sbuf_printf(sb, "%b", dp->d_flags,
                "\20"
                "\2OPEN"
                "\3CANDELETE"
                "\4CANFLUSHCACHE"
                "\5UNMAPPEDBIO"
                "\6DIRECTCOMPLETION"
                "\10CANZONE"
                "\11WRITEPROTECT");

        sbuf_finish(sb);
        error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
        sbuf_delete(sb);
        return (error);
}

static int
sysctl_disks(SYSCTL_HANDLER_ARGS)
{
        int error;
        struct sbuf *sb;

        sb = sbuf_new_auto();
        g_waitfor_event(g_kern_disks, sb, M_WAITOK, NULL);
        error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
        sbuf_delete(sb);
        return error;
}

SYSCTL_PROC(_kern, OID_AUTO, disks,
    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
    sysctl_disks, "A", "names of available disks");