/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2015 Netflix, Inc.
 *
 * 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 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.
 *
 * Derived from ata_da.c:
 * Copyright (c) 2009 Alexander Motin <mav@FreeBSD.org>
 */

#include <sys/param.h>

#ifdef _KERNEL
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/bio.h>
#include <sys/sysctl.h>
#include <sys/taskqueue.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/conf.h>
#include <sys/devicestat.h>
#include <sys/eventhandler.h>
#include <sys/malloc.h>
#include <sys/cons.h>
#include <sys/power.h>
#include <sys/proc.h>
#include <sys/reboot.h>
#include <sys/sbuf.h>
#include <geom/geom.h>
#include <geom/geom_disk.h>
#endif /* _KERNEL */

#ifndef _KERNEL
#include <stdio.h>
#include <string.h>
#endif /* _KERNEL */

#include <cam/cam.h>
#include <cam/cam_ccb.h>
#include <cam/cam_periph.h>
#include <cam/cam_xpt_periph.h>
#include <cam/cam_sim.h>
#include <cam/cam_iosched.h>

#include <cam/nvme/nvme_all.h>

typedef enum {
        NDA_STATE_NORMAL
} nda_state;

typedef enum {
        NDA_FLAG_OPEN           = 0x0001,
        NDA_FLAG_DIRTY          = 0x0002,
        NDA_FLAG_SCTX_INIT      = 0x0004,
        NDA_FLAG_RESCAN         = 0x0008,
} nda_flags;
#define NDA_FLAG_STRING         \
        "\020"                  \
        "\001OPEN"              \
        "\002DIRTY"             \
        "\003SCTX_INIT"         \
        "\004RESCAN"

typedef enum {
        NDA_Q_4K   = 0x01,
        NDA_Q_NONE = 0x00,
} nda_quirks;

#define NDA_Q_BIT_STRING        \
        "\020"                  \
        "\001Bit 0"

typedef enum {
        NDA_CCB_BUFFER_IO       = 0x01,
        NDA_CCB_DUMP            = 0x02,
        NDA_CCB_TRIM            = 0x03,
        NDA_CCB_PASS            = 0x04,
        NDA_CCB_TYPE_MASK       = 0x0F,
} nda_ccb_state;

/* Offsets into our private area for storing information */
#define ccb_state       ccb_h.ppriv_field0
#define ccb_bp          ccb_h.ppriv_ptr1        /* For NDA_CCB_BUFFER_IO */
#define ccb_trim        ccb_h.ppriv_ptr1        /* For NDA_CCB_TRIM */

struct nda_softc {
        struct   cam_iosched_softc *cam_iosched;
        int                     outstanding_cmds;       /* Number of active commands */
        int                     refcount;               /* Active xpt_action() calls */
        nda_state               state;
        nda_flags               flags;
        nda_quirks              quirks;
        int                     unmappedio;
        quad_t                  deletes;
        uint32_t                nsid;                   /* Namespace ID for this nda device */
        struct disk             *disk;
        struct task             sysctl_task;
        struct sysctl_ctx_list  sysctl_ctx;
        struct sysctl_oid       *sysctl_tree;
        uint64_t                trim_count;
        uint64_t                trim_ranges;
        uint64_t                trim_lbas;
#ifdef CAM_TEST_FAILURE
        int                     force_read_error;
        int                     force_write_error;
        int                     periodic_read_error;
        int                     periodic_read_count;
#endif
#ifdef CAM_IO_STATS
        struct sysctl_ctx_list  sysctl_stats_ctx;
        struct sysctl_oid       *sysctl_stats_tree;
        u_int                   timeouts;
        u_int                   errors;
        u_int                   invalidations;
#endif
};

struct nda_trim_request {
        struct nvme_dsm_range   dsm[NVME_MAX_DSM_TRIM / sizeof(struct nvme_dsm_range)];
        TAILQ_HEAD(, bio) bps;
};
_Static_assert(NVME_MAX_DSM_TRIM % sizeof(struct nvme_dsm_range) == 0,
    "NVME_MAX_DSM_TRIM must be an integral number of ranges");

/* Need quirk table */

static  disk_ioctl_t    ndaioctl;
static  disk_strategy_t ndastrategy;
static  dumper_t        ndadump;
static  periph_init_t   ndainit;
static  void            ndaasync(void *callback_arg, uint32_t code,
                                struct cam_path *path, void *arg);
static  void            ndasysctlinit(void *context, int pending);
static  int             ndaflagssysctl(SYSCTL_HANDLER_ARGS);
static  periph_ctor_t   ndaregister;
static  periph_dtor_t   ndacleanup;
static  periph_start_t  ndastart;
static  periph_oninv_t  ndaoninvalidate;
static  void            ndadone(struct cam_periph *periph,
                               union ccb *done_ccb);
static  int             ndaerror(union ccb *ccb, uint32_t cam_flags,
                                uint32_t sense_flags);
static void             ndashutdown(void *arg, int howto);
static void             ndasuspend(void *arg, enum power_stype stype);

#ifndef NDA_DEFAULT_SEND_ORDERED
#define NDA_DEFAULT_SEND_ORDERED        1
#endif
#ifndef NDA_DEFAULT_TIMEOUT
#define NDA_DEFAULT_TIMEOUT 30  /* Timeout in seconds */
#endif
#ifndef NDA_DEFAULT_RETRY
#define NDA_DEFAULT_RETRY       4
#endif
#ifndef NDA_MAX_TRIM_ENTRIES
#define NDA_MAX_TRIM_ENTRIES  (NVME_MAX_DSM_TRIM / sizeof(struct nvme_dsm_range))/* Number of DSM trims to use, max 256 */
#endif

static SYSCTL_NODE(_kern_cam, OID_AUTO, nda, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
    "CAM Direct Access Disk driver");

//static int nda_retry_count = NDA_DEFAULT_RETRY;
static int nda_send_ordered = NDA_DEFAULT_SEND_ORDERED;
static int nda_default_timeout = NDA_DEFAULT_TIMEOUT;
static int nda_max_trim_entries = NDA_MAX_TRIM_ENTRIES;
static int nda_enable_biospeedup = 1;
static int nda_nvd_compat = 1;
SYSCTL_INT(_kern_cam_nda, OID_AUTO, max_trim, CTLFLAG_RDTUN,
    &nda_max_trim_entries, NDA_MAX_TRIM_ENTRIES,
    "Maximum number of BIO_DELETE to send down as a DSM TRIM.");
SYSCTL_INT(_kern_cam_nda, OID_AUTO, enable_biospeedup, CTLFLAG_RDTUN,
    &nda_enable_biospeedup, 0, "Enable BIO_SPEEDUP processing.");
SYSCTL_INT(_kern_cam_nda, OID_AUTO, nvd_compat, CTLFLAG_RDTUN,
    &nda_nvd_compat, 1, "Enable creation of nvd aliases.");

/*
 * All NVMe media is non-rotational, so all nvme device instances
 * share this to implement the sysctl.
 */
static int nda_rotating_media = 0;

static struct periph_driver ndadriver =
{
        ndainit, "nda",
        TAILQ_HEAD_INITIALIZER(ndadriver.units), /* generation */ 0
};

PERIPHDRIVER_DECLARE(nda, ndadriver);

static MALLOC_DEFINE(M_NVMEDA, "nvme_da", "nvme_da buffers");

/*
 * nice wrappers. Maybe these belong in nvme_all.c instead of
 * here, but this is the only place that uses these. Should
 * we ever grow another NVME periph, we should move them
 * all there wholesale.
 */

static void
nda_nvme_flush(struct nda_softc *softc, struct ccb_nvmeio *nvmeio)
{
        cam_fill_nvmeio(nvmeio,
            0,                  /* retries */
            ndadone,            /* cbfcnp */
            CAM_DIR_NONE,       /* flags */
            NULL,               /* data_ptr */
            0,                  /* dxfer_len */
            nda_default_timeout * 1000); /* timeout 30s */
        nvme_ns_flush_cmd(&nvmeio->cmd, softc->nsid);
}

static void
nda_nvme_trim(struct nda_softc *softc, struct ccb_nvmeio *nvmeio,
    void *payload, uint32_t num_ranges)
{
        cam_fill_nvmeio(nvmeio,
            0,                  /* retries */
            ndadone,            /* cbfcnp */
            CAM_DIR_OUT,        /* flags */
            payload,            /* data_ptr */
            num_ranges * sizeof(struct nvme_dsm_range), /* dxfer_len */
            nda_default_timeout * 1000); /* timeout 30s */
        nvme_ns_trim_cmd(&nvmeio->cmd, softc->nsid, num_ranges);
}

static void
nda_nvme_write(struct nda_softc *softc, struct ccb_nvmeio *nvmeio,
    void *payload, uint64_t lba, uint32_t len, uint32_t count)
{
        cam_fill_nvmeio(nvmeio,
            0,                  /* retries */
            ndadone,            /* cbfcnp */
            CAM_DIR_OUT,        /* flags */
            payload,            /* data_ptr */
            len,                /* dxfer_len */
            nda_default_timeout * 1000); /* timeout 30s */
        nvme_ns_write_cmd(&nvmeio->cmd, softc->nsid, lba, count);
}

static void
nda_nvme_rw_bio(struct nda_softc *softc, struct ccb_nvmeio *nvmeio,
    struct bio *bp, uint32_t rwcmd)
{
        int flags = rwcmd == NVME_OPC_READ ? CAM_DIR_IN : CAM_DIR_OUT;
        void *payload;
        uint64_t lba;
        uint32_t count;

        if (bp->bio_flags & BIO_UNMAPPED) {
                flags |= CAM_DATA_BIO;
                payload = bp;
        } else {
                payload = bp->bio_data;
        }

        lba = bp->bio_pblkno;
        count = bp->bio_bcount / softc->disk->d_sectorsize;

        cam_fill_nvmeio(nvmeio,
            0,                  /* retries */
            ndadone,            /* cbfcnp */
            flags,              /* flags */
            payload,            /* data_ptr */
            bp->bio_bcount,     /* dxfer_len */
            nda_default_timeout * 1000); /* timeout 30s */
        nvme_ns_rw_cmd(&nvmeio->cmd, rwcmd, softc->nsid, lba, count);
}

static void
ndasetgeom(struct nda_softc *softc, struct cam_periph *periph)
{
        struct disk *disk = softc->disk;
        const struct nvme_namespace_data *nsd;
        const struct nvme_controller_data *cd;
        uint8_t flbas_fmt, lbads, vwc_present;
        u_int flags;

        nsd = nvme_get_identify_ns(periph);
        cd = nvme_get_identify_cntrl(periph);

        /*
         * Preserve flags we can't infer that were set before. UNMAPPED comes
         * from the PIM, so won't change after we set it the first
         * time. Subsequent times, we have to preserve it.
         */
        flags = disk->d_flags & DISKFLAG_UNMAPPED_BIO;  /* Need to preserve */

        flbas_fmt = NVMEV(NVME_NS_DATA_FLBAS_FORMAT, nsd->flbas);
        lbads = NVMEV(NVME_NS_DATA_LBAF_LBADS, nsd->lbaf[flbas_fmt]);
        disk->d_sectorsize = 1 << lbads;
        disk->d_mediasize = (off_t)(disk->d_sectorsize * nsd->nsze);
        disk->d_delmaxsize = disk->d_mediasize;
        disk->d_flags = DISKFLAG_DIRECT_COMPLETION;
        if (nvme_ctrlr_has_dataset_mgmt(cd))
                disk->d_flags |= DISKFLAG_CANDELETE;
        vwc_present = NVMEV(NVME_CTRLR_DATA_VWC_PRESENT, cd->vwc);
        if (vwc_present)
                disk->d_flags |= DISKFLAG_CANFLUSHCACHE;
        disk->d_flags |= flags;
}

static void
ndaopen_rescan_done(struct cam_periph *periph, union ccb *ccb)
{
        struct nda_softc *softc;

        softc = (struct nda_softc *)periph->softc;

        cam_periph_assert(periph, MA_OWNED);

        softc->flags &= ~NDA_FLAG_RESCAN;
        xpt_release_ccb(ccb);
        wakeup(&softc->disk->d_mediasize);
}


static int
ndaopen(struct disk *dp)
{
        struct cam_periph *periph;
        struct nda_softc *softc;
        union ccb *ccb;
        int error;

        periph = (struct cam_periph *)dp->d_drv1;
        if (cam_periph_acquire(periph) != 0) {
                return(ENXIO);
        }

        cam_periph_lock(periph);
        if ((error = cam_periph_hold(periph, PRIBIO|PCATCH)) != 0) {
                cam_periph_unlock(periph);
                cam_periph_release(periph);
                return (error);
        }

        softc = (struct nda_softc *)periph->softc;
        CAM_DEBUG(periph->path, CAM_DEBUG_TRACE | CAM_DEBUG_PERIPH,
            ("ndaopen\n"));

        /*
         * Rescan the lun in case the mediasize or sectorsize has changed since
         * we probed the device. Format and secure erase operations can do this,
         * but the nvme standard doesn't require a async notification of that
         * happening. da/ada do this by restarting their probe, but since
         * nvme_xpt gets the identify information we need, we just rescan here
         * since it's the easiest way to notice size changes.
         *
         * Not acquiring / releasing for the geom probe -- it's inline
         */
        ccb = cam_periph_getccb(periph, CAM_PRIORITY_NORMAL);
        ccb->ccb_h.func_code = XPT_SCAN_LUN;
        ccb->ccb_h.cbfcnp = ndaopen_rescan_done;
        ccb->ccb_h.ppriv_ptr0 = periph;
        ccb->crcn.flags = 0;
        xpt_action(ccb);

        softc->flags |= NDA_FLAG_RESCAN;
        error = 0;
        while ((softc->flags & NDA_FLAG_RESCAN) != 0 && error == 0)
                error = cam_periph_sleep(periph, &softc->disk->d_mediasize, PRIBIO,
                    "ndareprobe", 0);
        if (error != 0)
                xpt_print(periph->path, "Unable to retrieve capacity data\n");
        else
                ndasetgeom(softc, periph);

        softc->flags |= NDA_FLAG_OPEN;

        cam_periph_unhold(periph);
        cam_periph_unlock(periph);
        return (0);
}

static int
ndaclose(struct disk *dp)
{
        struct  cam_periph *periph;
        struct  nda_softc *softc;
        union ccb *ccb;
        int error;

        periph = (struct cam_periph *)dp->d_drv1;
        softc = (struct nda_softc *)periph->softc;
        cam_periph_lock(periph);

        CAM_DEBUG(periph->path, CAM_DEBUG_TRACE | CAM_DEBUG_PERIPH,
            ("ndaclose\n"));

        if ((softc->flags & NDA_FLAG_DIRTY) != 0 &&
            (periph->flags & CAM_PERIPH_INVALID) == 0 &&
            cam_periph_hold(periph, PRIBIO) == 0) {
                ccb = cam_periph_getccb(periph, CAM_PRIORITY_NORMAL);
                nda_nvme_flush(softc, &ccb->nvmeio);
                error = cam_periph_runccb(ccb, ndaerror, /*cam_flags*/0,
                    /*sense_flags*/0, softc->disk->d_devstat);

                if (error != 0)
                        xpt_print(periph->path, "Synchronize cache failed\n");
                else
                        softc->flags &= ~NDA_FLAG_DIRTY;
                xpt_release_ccb(ccb);
                cam_periph_unhold(periph);
        }

        softc->flags &= ~NDA_FLAG_OPEN;

        while (softc->refcount != 0)
                cam_periph_sleep(periph, &softc->refcount, PRIBIO, "ndaclose", 1);
        KASSERT(softc->outstanding_cmds == 0,
            ("nda %d outstanding commands", softc->outstanding_cmds));
        cam_periph_unlock(periph);
        cam_periph_release(periph);
        return (0);
}

static void
ndaschedule(struct cam_periph *periph)
{
        struct nda_softc *softc = (struct nda_softc *)periph->softc;

        if (softc->state != NDA_STATE_NORMAL)
                return;

        cam_iosched_schedule(softc->cam_iosched, periph);
}

static int
ndaioctl(struct disk *dp, u_long cmd, void *data, int fflag,
    struct thread *td)
{
        struct cam_periph *periph;

        periph = (struct cam_periph *)dp->d_drv1;

        switch (cmd) {
        case NVME_IO_TEST:
        case NVME_BIO_TEST:
                /*
                 * These don't map well to the underlying CCBs, so
                 * they are usupported via CAM.
                 */
                return (ENOTTY);
        case NVME_GET_NSID:
        {
                struct nvme_get_nsid *gnsid = (struct nvme_get_nsid *)data;
                struct ccb_pathinq cpi;

                xpt_path_inq(&cpi, periph->path);
                strncpy(gnsid->cdev, cpi.xport_specific.nvme.dev_name,
                    sizeof(gnsid->cdev));
                gnsid->nsid = cpi.xport_specific.nvme.nsid;
                return (0);
        }
        case NVME_PASSTHROUGH_CMD:
        {
                struct nvme_pt_command *pt;
                union ccb *ccb;
                struct cam_periph_map_info mapinfo;
                u_int maxmap = dp->d_maxsize;
                int error;

                /*
                 * Create a NVME_IO CCB to do the passthrough command.
                 */
                pt = (struct nvme_pt_command *)data;
                ccb = xpt_alloc_ccb();
                xpt_setup_ccb(&ccb->ccb_h, periph->path, CAM_PRIORITY_NORMAL);
                ccb->ccb_state = NDA_CCB_PASS;
                cam_fill_nvmeio(&ccb->nvmeio,
                    0,                  /* Retries */
                    ndadone,
                    (pt->is_read ? CAM_DIR_IN : CAM_DIR_OUT) | CAM_DATA_VADDR,
                    pt->buf,
                    pt->len,
                    nda_default_timeout * 1000);
                memcpy(&ccb->nvmeio.cmd, &pt->cmd, sizeof(pt->cmd));

                /*
                 * Wire the user memory in this request for the I/O
                 */
                memset(&mapinfo, 0, sizeof(mapinfo));
                error = cam_periph_mapmem(ccb, &mapinfo, maxmap);
                if (error)
                        goto out;

                /*
                 * Lock the periph and run the command.
                 */
                cam_periph_lock(periph);
                cam_periph_runccb(ccb, NULL, CAM_RETRY_SELTO,
                    SF_RETRY_UA | SF_NO_PRINT, NULL);

                /*
                 * Tear down mapping and return status.
                 */
                cam_periph_unlock(periph);
                error = cam_periph_unmapmem(ccb, &mapinfo);
                if (!cam_ccb_success(ccb))
                        error = EIO;
out:
                cam_periph_lock(periph);
                xpt_release_ccb(ccb);
                cam_periph_unlock(periph);
                return (error);
        }
        default:
                break;
        }
        return (ENOTTY);
}

/*
 * Actually translate the requested transfer into one the physical driver
 * can understand.  The transfer is described by a buf and will include
 * only one physical transfer.
 */
static void
ndastrategy(struct bio *bp)
{
        struct cam_periph *periph;
        struct nda_softc *softc;

        periph = (struct cam_periph *)bp->bio_disk->d_drv1;
        softc = (struct nda_softc *)periph->softc;

        cam_periph_lock(periph);

        CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("ndastrategy(%p)\n", bp));

        /*
         * If the device has been made invalid, error out
         */
        if ((periph->flags & CAM_PERIPH_INVALID) != 0) {
                cam_periph_unlock(periph);
                biofinish(bp, NULL, ENXIO);
                return;
        }

        if (bp->bio_cmd == BIO_DELETE)
                softc->deletes++;

        /*
         * Place it in the queue of disk activities for this disk
         */
        cam_iosched_queue_work(softc->cam_iosched, bp);

        /*
         * Schedule ourselves for performing the work.
         */
        ndaschedule(periph);
        cam_periph_unlock(periph);

        return;
}

static int
ndadump(void *arg, void *virtual, off_t offset, size_t length)
{
        struct      cam_periph *periph;
        struct      nda_softc *softc;
        u_int       secsize;
        struct ccb_nvmeio nvmeio;
        struct      disk *dp;
        uint64_t    lba;
        uint32_t    count;
        int         error = 0;

        dp = arg;
        periph = dp->d_drv1;
        softc = (struct nda_softc *)periph->softc;
        secsize = softc->disk->d_sectorsize;
        lba = offset / secsize;
        count = length / secsize;

        if ((periph->flags & CAM_PERIPH_INVALID) != 0)
                return (ENXIO);

        /* xpt_get_ccb returns a zero'd allocation for the ccb, mimic that here */
        memset(&nvmeio, 0, sizeof(nvmeio));
        if (length > 0) {
                xpt_setup_ccb(&nvmeio.ccb_h, periph->path, CAM_PRIORITY_NORMAL);
                nvmeio.ccb_state = NDA_CCB_DUMP;
                nda_nvme_write(softc, &nvmeio, virtual, lba, length, count);
                error = cam_periph_runccb((union ccb *)&nvmeio, cam_periph_error,
                    0, SF_NO_RECOVERY | SF_NO_RETRY, NULL);
                if (error != 0)
                        printf("Aborting dump due to I/O error %d.\n", error);

                return (error);
        }

        /* Flush */
        xpt_setup_ccb(&nvmeio.ccb_h, periph->path, CAM_PRIORITY_NORMAL);

        nvmeio.ccb_state = NDA_CCB_DUMP;
        nda_nvme_flush(softc, &nvmeio);
        error = cam_periph_runccb((union ccb *)&nvmeio, cam_periph_error,
            0, SF_NO_RECOVERY | SF_NO_RETRY, NULL);
        if (error != 0)
                xpt_print(periph->path, "flush cmd failed\n");
        return (error);
}

static void
ndainit(void)
{
        cam_status status;

        /*
         * Install a global async callback.  This callback will
         * receive async callbacks like "new device found".
         */
        status = xpt_register_async(AC_FOUND_DEVICE, ndaasync, NULL, NULL);

        if (status != CAM_REQ_CMP) {
                printf("nda: Failed to attach master async callback "
                       "due to status 0x%x!\n", status);
        } else if (nda_send_ordered) {
                /* Register our event handlers */
                if ((EVENTHANDLER_REGISTER(power_suspend, ndasuspend,
                                           NULL, EVENTHANDLER_PRI_LAST)) == NULL)
                    printf("ndainit: power event registration failed!\n");
                if ((EVENTHANDLER_REGISTER(shutdown_post_sync, ndashutdown,
                                           NULL, SHUTDOWN_PRI_DEFAULT)) == NULL)
                    printf("ndainit: shutdown event registration failed!\n");
        }
}

/*
 * Callback from GEOM, called when it has finished cleaning up its
 * resources.
 */
static void
ndadiskgonecb(struct disk *dp)
{
        struct cam_periph *periph;

        periph = (struct cam_periph *)dp->d_drv1;

        cam_periph_release(periph);
}

static void
ndaoninvalidate(struct cam_periph *periph)
{
        struct nda_softc *softc;

        softc = (struct nda_softc *)periph->softc;

        /*
         * De-register any async callbacks.
         */
        xpt_register_async(0, ndaasync, periph, periph->path);
#ifdef CAM_IO_STATS
        softc->invalidations++;
#endif

        /*
         * Return all queued I/O with ENXIO. Transactions may be queued up here
         * for retry (since we are called while there's other transactions
         * pending). Any requests in the hardware will drain before ndacleanup
         * is called.
         */
        cam_iosched_flush(softc->cam_iosched, NULL, ENXIO);

        /*
         * Tell GEOM that we've gone away, we'll get a callback when it is
         * done cleaning up its resources.
         */
        disk_gone(softc->disk);
}

static void
ndacleanup(struct cam_periph *periph)
{
        struct nda_softc *softc;

        softc = (struct nda_softc *)periph->softc;

        cam_periph_unlock(periph);

        cam_iosched_fini(softc->cam_iosched);

        /*
         * If we can't free the sysctl tree, oh well...
         */
        if ((softc->flags & NDA_FLAG_SCTX_INIT) != 0) {
#ifdef CAM_IO_STATS
                if (sysctl_ctx_free(&softc->sysctl_stats_ctx) != 0)
                        xpt_print(periph->path,
                            "can't remove sysctl stats context\n");
#endif
                if (sysctl_ctx_free(&softc->sysctl_ctx) != 0)
                        xpt_print(periph->path,
                            "can't remove sysctl context\n");
        }

        disk_destroy(softc->disk);
        free(softc, M_DEVBUF);
        cam_periph_lock(periph);
}

static void
ndaasync(void *callback_arg, uint32_t code, struct cam_path *path, void *arg)
{
        struct cam_periph *periph = callback_arg;
        struct nda_softc *softc;

        switch (code) {
        case AC_FOUND_DEVICE:
        {
                struct ccb_getdev *cgd;
                cam_status status;

                cgd = (struct ccb_getdev *)arg;
                if (cgd == NULL)
                        break;

                if (cgd->protocol != PROTO_NVME)
                        break;

                /*
                 * Allocate a peripheral instance for
                 * this device and start the probe
                 * process.
                 */
                status = cam_periph_alloc(ndaregister, ndaoninvalidate,
                                          ndacleanup, ndastart,
                                          "nda", CAM_PERIPH_BIO,
                                          path, ndaasync,
                                          AC_FOUND_DEVICE, cgd);

                if (status != CAM_REQ_CMP
                 && status != CAM_REQ_INPROG)
                        printf("ndaasync: Unable to attach to new device "
                                "due to status 0x%x\n", status);
                break;
        }
        case AC_GETDEV_CHANGED:
        {
                off_t mediasize;
                u_int sectorsize;

                softc = periph->softc;
                mediasize = softc->disk->d_mediasize;
                sectorsize = softc->disk->d_sectorsize;
                ndasetgeom(softc, periph);
                /*
                 * If the sectorsize changed, then it's new media. Otherwise if
                 * the media size changed, resize the existing disk. Otherwise
                 * do nothing.
                 */
                if (sectorsize != softc->disk->d_sectorsize)
                        disk_media_changed(softc->disk, M_WAITOK);
                else if (mediasize != softc->disk->d_mediasize)
                        disk_resize(softc->disk, M_WAITOK);
                break;
        }
        case AC_ADVINFO_CHANGED:
        {
                uintptr_t buftype;

                /*
                 * Note: In theory, we could send CDAI_TYPE_NVME_* events here,
                 * but instead the rescan code only sends more specific
                 * AC_GETDEV_CHANGED. There's no way to generically get
                 * notifications of changes to these structures from the drive
                 * (though we could notice with memcmp). The automation in NVME
                 * is at a much more granular level, so we leverage that.
                 */
                softc = periph->softc;
                buftype = (uintptr_t)arg;
                if (buftype == CDAI_TYPE_PHYS_PATH) {
                        disk_attr_changed(softc->disk, "GEOM::physpath",
                            M_WAITOK);
                }
                break;
        }
        case AC_LOST_DEVICE:
        default:
                break;
        }
        cam_periph_async(periph, code, path, arg);
}

static void
ndasysctlinit(void *context, int pending)
{
        struct cam_periph *periph;
        struct nda_softc *softc;
        char tmpstr[32], tmpstr2[16];

        periph = (struct cam_periph *)context;

        /* periph was held for us when this task was enqueued */
        if ((periph->flags & CAM_PERIPH_INVALID) != 0) {
                cam_periph_release(periph);
                return;
        }

        softc = (struct nda_softc *)periph->softc;
        snprintf(tmpstr, sizeof(tmpstr), "CAM NDA unit %d", periph->unit_number);
        snprintf(tmpstr2, sizeof(tmpstr2), "%d", periph->unit_number);

        sysctl_ctx_init(&softc->sysctl_ctx);
        softc->flags |= NDA_FLAG_SCTX_INIT;
        softc->sysctl_tree = SYSCTL_ADD_NODE_WITH_LABEL(&softc->sysctl_ctx,
                SYSCTL_STATIC_CHILDREN(_kern_cam_nda), OID_AUTO, tmpstr2,
                CTLFLAG_RD | CTLFLAG_MPSAFE, 0, tmpstr, "device_index");
        if (softc->sysctl_tree == NULL) {
                printf("ndasysctlinit: unable to allocate sysctl tree\n");
                cam_periph_release(periph);
                return;
        }

        SYSCTL_ADD_INT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree),
            OID_AUTO, "unmapped_io", CTLFLAG_RD,
            &softc->unmappedio, 0, "Unmapped I/O leaf");

        SYSCTL_ADD_QUAD(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree),
            OID_AUTO, "deletes", CTLFLAG_RD,
            &softc->deletes, "Number of BIO_DELETE requests");

        SYSCTL_ADD_UQUAD(&softc->sysctl_ctx,
                SYSCTL_CHILDREN(softc->sysctl_tree), OID_AUTO,
                "trim_count", CTLFLAG_RD, &softc->trim_count,
                "Total number of unmap/dsm commands sent");
        SYSCTL_ADD_UQUAD(&softc->sysctl_ctx,
                SYSCTL_CHILDREN(softc->sysctl_tree), OID_AUTO,
                "trim_ranges", CTLFLAG_RD, &softc->trim_ranges,
                "Total number of ranges in unmap/dsm commands");
        SYSCTL_ADD_UQUAD(&softc->sysctl_ctx,
                SYSCTL_CHILDREN(softc->sysctl_tree), OID_AUTO,
                "trim_lbas", CTLFLAG_RD, &softc->trim_lbas,
                "Total lbas in the unmap/dsm commands sent");

        SYSCTL_ADD_INT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree),
            OID_AUTO, "rotating", CTLFLAG_RD, &nda_rotating_media, 1,
            "Rotating media");

        SYSCTL_ADD_PROC(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree),
            OID_AUTO, "flags", CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
            softc, 0, ndaflagssysctl, "A",
            "Flags for drive");

#ifdef CAM_IO_STATS
        softc->sysctl_stats_tree = SYSCTL_ADD_NODE(&softc->sysctl_stats_ctx,
                SYSCTL_CHILDREN(softc->sysctl_tree), OID_AUTO, "stats",
                CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "Statistics");
        if (softc->sysctl_stats_tree == NULL) {
                printf("ndasysctlinit: unable to allocate sysctl tree for stats\n");
                cam_periph_release(periph);
                return;
        }
        SYSCTL_ADD_INT(&softc->sysctl_stats_ctx,
                SYSCTL_CHILDREN(softc->sysctl_stats_tree),
                OID_AUTO, "timeouts", CTLFLAG_RD,
                &softc->timeouts, 0,
                "Device timeouts reported by the SIM");
        SYSCTL_ADD_INT(&softc->sysctl_stats_ctx,
                SYSCTL_CHILDREN(softc->sysctl_stats_tree),
                OID_AUTO, "errors", CTLFLAG_RD,
                &softc->errors, 0,
                "Transport errors reported by the SIM.");
        SYSCTL_ADD_INT(&softc->sysctl_stats_ctx,
                SYSCTL_CHILDREN(softc->sysctl_stats_tree),
                OID_AUTO, "pack_invalidations", CTLFLAG_RD,
                &softc->invalidations, 0,
                "Device pack invalidations.");
#endif

#ifdef CAM_TEST_FAILURE
        SYSCTL_ADD_PROC(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree),
                OID_AUTO, "invalidate", CTLTYPE_U64 | CTLFLAG_RW | CTLFLAG_MPSAFE,
                periph, 0, cam_periph_invalidate_sysctl, "I",
                "Write 1 to invalidate the drive immediately");
#endif

        cam_iosched_sysctl_init(softc->cam_iosched, &softc->sysctl_ctx,
            softc->sysctl_tree);

        cam_periph_release(periph);
}

static int
ndaflagssysctl(SYSCTL_HANDLER_ARGS)
{
        struct sbuf sbuf;
        struct nda_softc *softc = arg1;
        int error;

        sbuf_new_for_sysctl(&sbuf, NULL, 0, req);
        if (softc->flags != 0)
                sbuf_printf(&sbuf, "0x%b", (unsigned)softc->flags, NDA_FLAG_STRING);
        else
                sbuf_putc(&sbuf, '0');
        error = sbuf_finish(&sbuf);
        sbuf_delete(&sbuf);

        return (error);
}

static int
ndagetattr(struct bio *bp)
{
        int ret;
        struct cam_periph *periph;

        if (g_handleattr_int(bp, "GEOM::canspeedup", nda_enable_biospeedup))
                return (EJUSTRETURN);

        periph = (struct cam_periph *)bp->bio_disk->d_drv1;
        cam_periph_lock(periph);
        ret = xpt_getattr(bp->bio_data, bp->bio_length, bp->bio_attribute,
            periph->path);
        cam_periph_unlock(periph);
        if (ret == 0)
                bp->bio_completed = bp->bio_length;
        return ret;
}

static cam_status
ndaregister(struct cam_periph *periph, void *arg)
{
        struct nda_softc *softc;
        struct disk *disk;
        struct ccb_pathinq cpi;
        const struct nvme_namespace_data *nsd;
        const struct nvme_controller_data *cd;
        char   announce_buf[80];
        u_int maxio;
        int quirks;

        nsd = nvme_get_identify_ns(periph);
        cd = nvme_get_identify_cntrl(periph);

        softc = (struct nda_softc *)malloc(sizeof(*softc), M_DEVBUF,
            M_NOWAIT | M_ZERO);

        if (softc == NULL) {
                printf("ndaregister: Unable to probe new device. "
                    "Unable to allocate softc\n");
                return(CAM_REQ_CMP_ERR);
        }

        /* ident_data parsing */

        periph->softc = softc;
        softc->quirks = NDA_Q_NONE;
        xpt_path_inq(&cpi, periph->path);
        TASK_INIT(&softc->sysctl_task, 0, ndasysctlinit, periph);

        /*
         * The name space ID is the lun, save it for later I/O
         */
        softc->nsid = (uint32_t)xpt_path_lun_id(periph->path);

        /*
         * Register this media as a disk
         */
        (void)cam_periph_acquire(periph);
        cam_periph_unlock(periph);
        snprintf(announce_buf, sizeof(announce_buf),
            "kern.cam.nda.%d.quirks", periph->unit_number);
        quirks = softc->quirks;
        TUNABLE_INT_FETCH(announce_buf, &quirks);
        softc->quirks = quirks;
        softc->disk = disk = disk_alloc();
        disk->d_rotation_rate = DISK_RR_NON_ROTATING;
        disk->d_open = ndaopen;
        disk->d_close = ndaclose;
        disk->d_strategy = ndastrategy;
        disk->d_ioctl = ndaioctl;
        disk->d_getattr = ndagetattr;
        if (cam_sim_pollable(periph->sim))
                disk->d_dump = ndadump;
        disk->d_gone = ndadiskgonecb;
        disk->d_name = "nda";
        disk->d_drv1 = periph;
        disk->d_unit = periph->unit_number;
        maxio = cpi.maxio;              /* Honor max I/O size of SIM */
        if (maxio == 0)
                maxio = DFLTPHYS;       /* traditional default */
        else if (maxio > maxphys)
                maxio = maxphys;        /* for safety */
        disk->d_maxsize = maxio;
        ndasetgeom(softc, periph);
        if ((cpi.hba_misc & PIM_UNMAPPED) != 0) {
                disk->d_flags |= DISKFLAG_UNMAPPED_BIO;
                softc->unmappedio = 1;
        }

        /*
         * d_ident and d_descr are both far bigger than the length of either
         *  the serial or model number strings.
         */
        cam_strvis_flag(disk->d_descr, cd->mn, NVME_MODEL_NUMBER_LENGTH,
            sizeof(disk->d_descr), CAM_STRVIS_FLAG_NONASCII_SPC);

        cam_strvis_flag(disk->d_ident, cd->sn, NVME_SERIAL_NUMBER_LENGTH,
            sizeof(disk->d_ident), CAM_STRVIS_FLAG_NONASCII_SPC);

        disk->d_hba_vendor = cpi.hba_vendor;
        disk->d_hba_device = cpi.hba_device;
        disk->d_hba_subvendor = cpi.hba_subvendor;
        disk->d_hba_subdevice = cpi.hba_subdevice;
        snprintf(disk->d_attachment, sizeof(disk->d_attachment),
            "%s%d", cpi.dev_name, cpi.unit_number);
        if (NVMEV(NVME_NS_DATA_NSFEAT_NPVALID, nsd->nsfeat) != 0 &&
            nsd->npwg != 0)
                disk->d_stripesize = ((nsd->npwg + 1) * disk->d_sectorsize);
        else
                disk->d_stripesize = nsd->noiob * disk->d_sectorsize;
        disk->d_stripeoffset = 0;
        disk->d_devstat = devstat_new_entry(periph->periph_name,
            periph->unit_number, disk->d_sectorsize,
            DEVSTAT_ALL_SUPPORTED,
            DEVSTAT_TYPE_DIRECT | XPORT_DEVSTAT_TYPE(cpi.transport),
            DEVSTAT_PRIORITY_DISK);

        if (cam_iosched_init(&softc->cam_iosched, periph, disk,
            ndaschedule) != 0) {
                printf("ndaregister: Unable to probe new device. "
                       "Unable to allocate iosched memory\n");
                free(softc, M_DEVBUF);
                return(CAM_REQ_CMP_ERR);
        }
        cam_iosched_set_sort_queue(softc->cam_iosched, 0);

        /*
         * Add alias for older nvd drives to ease transition.
         */
        if (nda_nvd_compat)
                disk_add_alias(disk, "nvd");

        cam_periph_lock(periph);

        snprintf(announce_buf, sizeof(announce_buf),
                "%juMB (%ju %u byte sectors)",
            (uintmax_t)((uintmax_t)disk->d_mediasize / (1024*1024)),
                (uintmax_t)disk->d_mediasize / disk->d_sectorsize,
                disk->d_sectorsize);
        xpt_announce_periph(periph, announce_buf);
        xpt_announce_quirks(periph, softc->quirks, NDA_Q_BIT_STRING);

        /*
         * Create our sysctl variables, now that we know
         * we have successfully attached.
         */
        if (cam_periph_acquire(periph) == 0)
                taskqueue_enqueue(taskqueue_thread, &softc->sysctl_task);

        /*
         * Register for device going away and info about the drive
         * changing (though with NVMe, it can't)
         */
        xpt_register_async(AC_LOST_DEVICE | AC_ADVINFO_CHANGED | AC_GETDEV_CHANGED,
            ndaasync, periph, periph->path);

        softc->state = NDA_STATE_NORMAL;

        /*
         * We'll release this reference once GEOM calls us back via
         * ndadiskgonecb(), telling us that our provider has been freed.
         */
        if (cam_periph_acquire(periph) == 0)
                disk_create(softc->disk, DISK_VERSION);

        cam_periph_release_locked(periph);
        return(CAM_REQ_CMP);
}

static void
ndastart(struct cam_periph *periph, union ccb *start_ccb)
{
        struct nda_softc *softc = (struct nda_softc *)periph->softc;
        struct ccb_nvmeio *nvmeio = &start_ccb->nvmeio;

        CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("ndastart\n"));

        switch (softc->state) {
        case NDA_STATE_NORMAL:
        {
                struct bio *bp;

                bp = cam_iosched_next_bio(softc->cam_iosched);
                CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("ndastart: bio %p\n", bp));
                if (bp == NULL) {
                        xpt_release_ccb(start_ccb);
                        break;
                }

                switch (bp->bio_cmd) {
                case BIO_WRITE:
                        softc->flags |= NDA_FLAG_DIRTY;
                        /* FALLTHROUGH */
                case BIO_READ:
                {
#ifdef CAM_TEST_FAILURE
                        int fail = 0;

                        /*
                         * Support the failure ioctls.  If the command is a
                         * read, and there are pending forced read errors, or
                         * if a write and pending write errors, then fail this
                         * operation with EIO.  This is useful for testing
                         * purposes.  Also, support having every Nth read fail.
                         *
                         * This is a rather blunt tool.
                         */
                        if (bp->bio_cmd == BIO_READ) {
                                if (softc->force_read_error) {
                                        softc->force_read_error--;
                                        fail = 1;
                                }
                                if (softc->periodic_read_error > 0) {
                                        if (++softc->periodic_read_count >=
                                            softc->periodic_read_error) {
                                                softc->periodic_read_count = 0;
                                                fail = 1;
                                        }
                                }
                        } else {
                                if (softc->force_write_error) {
                                        softc->force_write_error--;
                                        fail = 1;
                                }
                        }
                        if (fail) {
                                biofinish(bp, NULL, EIO);
                                xpt_release_ccb(start_ccb);
                                ndaschedule(periph);
                                return;
                        }
#endif
                        KASSERT((bp->bio_flags & BIO_UNMAPPED) == 0 ||
                            round_page(bp->bio_bcount + bp->bio_ma_offset) /
                            PAGE_SIZE == bp->bio_ma_n,
                            ("Short bio %p", bp));
                        nda_nvme_rw_bio(softc, &start_ccb->nvmeio, bp, bp->bio_cmd == BIO_READ ?
                            NVME_OPC_READ : NVME_OPC_WRITE);
                        break;
                }
                case BIO_DELETE:
                {
                        struct nvme_dsm_range *dsm_range, *dsm_end;
                        struct nda_trim_request *trim;
                        struct bio *bp1;
                        int ents;
                        uint32_t totalcount = 0, ranges = 0;

                        trim = malloc(sizeof(*trim), M_NVMEDA, M_ZERO | M_NOWAIT);
                        if (trim == NULL) {
                                /*
                                 * We have to drop the periph lock when
                                 * returning ENOMEM. g_io_deliver treats these
                                 * request differently and will recursively call
                                 * the start routine which causes us to get into
                                 * ndastrategy with the periph lock held,
                                 * leading to a panic when its acquired again.
                                 */
                                cam_periph_unlock(periph);
                                biofinish(bp, NULL, ENOMEM);
                                cam_periph_lock(periph);
                                xpt_release_ccb(start_ccb);
                                ndaschedule(periph);
                                return;
                        }
                        TAILQ_INIT(&trim->bps);
                        bp1 = bp;
                        ents = min(nitems(trim->dsm), nda_max_trim_entries);
                        ents = max(ents, 1);
                        dsm_range = trim->dsm;
                        dsm_end = dsm_range + ents;
                        do {
                                TAILQ_INSERT_TAIL(&trim->bps, bp1, bio_queue);
                                dsm_range->length =
                                    htole32(bp1->bio_bcount / softc->disk->d_sectorsize);
                                dsm_range->starting_lba =
                                    htole64(bp1->bio_offset / softc->disk->d_sectorsize);
                                ranges++;
                                totalcount += dsm_range->length;
                                dsm_range++;
                                if (dsm_range >= dsm_end)
                                        break;
                                bp1 = cam_iosched_next_trim(softc->cam_iosched);
                                /* XXX -- Could collapse adjacent ranges, but we don't for now */
                                /* XXX -- Could limit based on total payload size */
                        } while (bp1 != NULL);
                        start_ccb->ccb_trim = trim;
                        nda_nvme_trim(softc, &start_ccb->nvmeio, trim->dsm,
                            dsm_range - trim->dsm);
                        start_ccb->ccb_state = NDA_CCB_TRIM;
                        softc->trim_count++;
                        softc->trim_ranges += ranges;
                        softc->trim_lbas += totalcount;
                        /*
                         * Note: We can have multiple TRIMs in flight, so we don't call
                         * cam_iosched_submit_trim(softc->cam_iosched);
                         * since that forces the I/O scheduler to only schedule one at a time.
                         * On NVMe drives, this is a performance disaster.
                         */
                        goto out;
                }
                case BIO_FLUSH:
                        nda_nvme_flush(softc, nvmeio);
                        break;
                default:
                        biofinish(bp, NULL, EOPNOTSUPP);
                        xpt_release_ccb(start_ccb);
                        ndaschedule(periph);
                        return;
                }
                start_ccb->ccb_state = NDA_CCB_BUFFER_IO;
                start_ccb->ccb_bp = bp;
out:
                start_ccb->ccb_h.flags |= CAM_UNLOCKED;
                softc->outstanding_cmds++;
                softc->refcount++;                      /* For submission only */
                cam_periph_unlock(periph);
                xpt_action(start_ccb);
                cam_periph_lock(periph);
                softc->refcount--;                      /* Submission done */

                /* May have more work to do, so ensure we stay scheduled */
                ndaschedule(periph);
                break;
                }
        }
}

static void
ndadone(struct cam_periph *periph, union ccb *done_ccb)
{
        struct nda_softc *softc;
        struct ccb_nvmeio *nvmeio = &done_ccb->nvmeio;
        struct cam_path *path;
        int state;

        softc = (struct nda_softc *)periph->softc;
        path = done_ccb->ccb_h.path;

        CAM_DEBUG(path, CAM_DEBUG_TRACE, ("ndadone\n"));

        state = nvmeio->ccb_state & NDA_CCB_TYPE_MASK;
        switch (state) {
        case NDA_CCB_BUFFER_IO:
        case NDA_CCB_TRIM:
        {
                int error;

                cam_periph_lock(periph);
                if ((done_ccb->ccb_h.status & CAM_STATUS_MASK) != CAM_REQ_CMP) {
                        error = ndaerror(done_ccb, 0, 0);
                        if (error == ERESTART) {
                                /* A retry was scheduled, so just return. */
                                cam_periph_unlock(periph);
                                return;
                        }
                        if ((done_ccb->ccb_h.status & CAM_DEV_QFRZN) != 0)
                                cam_release_devq(path,
                                                 /*relsim_flags*/0,
                                                 /*reduction*/0,
                                                 /*timeout*/0,
                                                 /*getcount_only*/0);
                } else {
                        if ((done_ccb->ccb_h.status & CAM_DEV_QFRZN) != 0)
                                panic("REQ_CMP with QFRZN");
                        error = 0;
                }
                if (state == NDA_CCB_BUFFER_IO) {
                        struct bio *bp;

                        bp = (struct bio *)done_ccb->ccb_bp;
                        bp->bio_error = error;
                        if (error != 0) {
                                bp->bio_resid = bp->bio_bcount;
                                bp->bio_flags |= BIO_ERROR;
                        } else {
                                bp->bio_resid = 0;
                        }
                        softc->outstanding_cmds--;

                        /*
                         * We need to call cam_iosched before we call biodone so that we
                         * don't measure any activity that happens in the completion
                         * routine, which in the case of sendfile can be quite
                         * extensive.
                         */
                        cam_iosched_bio_complete(softc->cam_iosched, bp, done_ccb);
                        xpt_release_ccb(done_ccb);
                        ndaschedule(periph);
                        cam_periph_unlock(periph);
                        biodone(bp);
                } else { /* state == NDA_CCB_TRIM */
                        struct nda_trim_request *trim;
                        struct bio *bp1, *bp2;
                        TAILQ_HEAD(, bio) queue;

                        trim = nvmeio->ccb_trim;
                        TAILQ_INIT(&queue);
                        TAILQ_CONCAT(&queue, &trim->bps, bio_queue);
                        free(trim, M_NVMEDA);

                        /*
                         * Since we can have multiple trims in flight, we don't
                         * need to call this here.
                         * cam_iosched_trim_done(softc->cam_iosched);
                         */
                        /*
                         * The the I/O scheduler that we're finishing the I/O
                         * so we can keep book. The first one we pass in the CCB
                         * which has the timing information. The rest we pass in NULL
                         * so we can keep proper counts.
                         */
                        bp1 = TAILQ_FIRST(&queue);
                        cam_iosched_bio_complete(softc->cam_iosched, bp1, done_ccb);
                        xpt_release_ccb(done_ccb);
                        softc->outstanding_cmds--;
                        ndaschedule(periph);
                        cam_periph_unlock(periph);
                        while ((bp2 = TAILQ_FIRST(&queue)) != NULL) {
                                TAILQ_REMOVE(&queue, bp2, bio_queue);
                                bp2->bio_error = error;
                                if (error != 0) {
                                        bp2->bio_flags |= BIO_ERROR;
                                        bp2->bio_resid = bp1->bio_bcount;
                                } else
                                        bp2->bio_resid = 0;
                                if (bp1 != bp2)
                                        cam_iosched_bio_complete(softc->cam_iosched, bp2, NULL);
                                biodone(bp2);
                        }
                }
                return;
        }
        case NDA_CCB_DUMP:
                /* No-op.  We're polling */
                return;
        case NDA_CCB_PASS:
                /* NVME_PASSTHROUGH_CMD runs this CCB and releases it */
                return;
        default:
                break;
        }
        xpt_release_ccb(done_ccb);
}

static int
ndaerror(union ccb *ccb, uint32_t cam_flags, uint32_t sense_flags)
{
#ifdef CAM_IO_STATS
        struct nda_softc *softc;
        struct cam_periph *periph;

        periph = xpt_path_periph(ccb->ccb_h.path);
        softc = (struct nda_softc *)periph->softc;
#endif

        switch (ccb->ccb_h.status & CAM_STATUS_MASK) {
        case CAM_CMD_TIMEOUT:
#ifdef CAM_IO_STATS
                softc->timeouts++;
#endif
                break;
        case CAM_REQ_CMP_ERR:
        case CAM_NVME_STATUS_ERROR:
#ifdef CAM_IO_STATS
                softc->errors++;
#endif
                break;
        default:
                break;
        }

        return(cam_periph_error(ccb, cam_flags, sense_flags));
}

/*
 * Step through all NDA peripheral drivers, and if the device is still open,
 * sync the disk cache to physical media.
 */
static void
ndaflush(void)
{
        struct cam_periph *periph;
        struct nda_softc *softc;
        union ccb *ccb;
        int error;

        CAM_PERIPH_FOREACH(periph, &ndadriver) {
                softc = (struct nda_softc *)periph->softc;

                if (SCHEDULER_STOPPED()) {
                        /*
                         * If we panicked with the lock held or the periph is not
                         * open, do not recurse.  Otherwise, call ndadump since
                         * that avoids the sleeping cam_periph_getccb does if no
                         * CCBs are available.
                         */
                        if (!cam_periph_owned(periph) &&
                            (softc->flags & NDA_FLAG_OPEN)) {
                                ndadump(softc->disk, NULL, 0, 0);
                        }
                        continue;
                }

                /*
                 * We only sync the cache if the drive is still open
                 */
                cam_periph_lock(periph);
                if ((softc->flags & NDA_FLAG_OPEN) == 0) {
                        cam_periph_unlock(periph);
                        continue;
                }

                ccb = cam_periph_getccb(periph, CAM_PRIORITY_NORMAL);
                nda_nvme_flush(softc, &ccb->nvmeio);
                error = cam_periph_runccb(ccb, ndaerror, /*cam_flags*/0,
                    /*sense_flags*/ SF_NO_RECOVERY | SF_NO_RETRY,
                    softc->disk->d_devstat);
                if (error != 0)
                        xpt_print(periph->path, "Synchronize cache failed\n");
                xpt_release_ccb(ccb);
                cam_periph_unlock(periph);
        }
}

static void
ndashutdown(void *arg, int howto)
{

        if ((howto & RB_NOSYNC) != 0)
                return;

        ndaflush();
}

static void
ndasuspend(void *arg, enum power_stype stype)
{

        ndaflush();
}