qemu/hw/block/nvme-ns.c

/*
 * QEMU NVM Express Virtual Namespace
 *
 * Copyright (c) 2019 CNEX Labs
 * Copyright (c) 2020 Samsung Electronics
 *
 * Authors:
 *  Klaus Jensen      <k.jensen@samsung.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2. See the
 * COPYING file in the top-level directory.
 *
 */

#include "qemu/osdep.h"
#include "qemu/units.h"
#include "qemu/cutils.h"
#include "qemu/log.h"
#include "hw/block/block.h"
#include "hw/pci/pci.h"
#include "sysemu/sysemu.h"
#include "sysemu/block-backend.h"
#include "qapi/error.h"

#include "hw/qdev-properties.h"
#include "hw/qdev-core.h"

#include "nvme.h"
#include "nvme-ns.h"

#define MIN_DISCARD_GRANULARITY (4 * KiB)

static int nvme_ns_init(NvmeNamespace *ns, Error **errp)
{
    BlockDriverInfo bdi;
    NvmeIdNs *id_ns = &ns->id_ns;
    int lba_index = NVME_ID_NS_FLBAS_INDEX(ns->id_ns.flbas);
    int npdg;

    ns->id_ns.dlfeat = 0x9;

    id_ns->lbaf[lba_index].ds = 31 - clz32(ns->blkconf.logical_block_size);

    id_ns->nsze = cpu_to_le64(nvme_ns_nlbas(ns));

    /* no thin provisioning */
    id_ns->ncap = id_ns->nsze;
    id_ns->nuse = id_ns->ncap;

    /* support DULBE and I/O optimization fields */
    id_ns->nsfeat |= (0x4 | 0x10);

    npdg = ns->blkconf.discard_granularity / ns->blkconf.logical_block_size;

    if (bdrv_get_info(blk_bs(ns->blkconf.blk), &bdi) >= 0 &&
        bdi.cluster_size > ns->blkconf.discard_granularity) {
        npdg = bdi.cluster_size / ns->blkconf.logical_block_size;
    }

    id_ns->npda = id_ns->npdg = npdg - 1;

    return 0;
}

static int nvme_ns_init_blk(NvmeCtrl *n, NvmeNamespace *ns, Error **errp)
{
    bool read_only;

    if (!blkconf_blocksizes(&ns->blkconf, errp)) {
        return -1;
    }

    read_only = !blk_supports_write_perm(ns->blkconf.blk);
    if (!blkconf_apply_backend_options(&ns->blkconf, read_only, false, errp)) {
        return -1;
    }

    if (ns->blkconf.discard_granularity == -1) {
        ns->blkconf.discard_granularity =
            MAX(ns->blkconf.logical_block_size, MIN_DISCARD_GRANULARITY);
    }

    ns->size = blk_getlength(ns->blkconf.blk);
    if (ns->size < 0) {
        error_setg_errno(errp, -ns->size, "could not get blockdev size");
        return -1;
    }

    if (blk_enable_write_cache(ns->blkconf.blk)) {
        n->features.vwc = 0x1;
    }

    return 0;
}

static int nvme_ns_check_constraints(NvmeNamespace *ns, Error **errp)
{
    if (!ns->blkconf.blk) {
        error_setg(errp, "block backend not configured");
        return -1;
    }

    return 0;
}

int nvme_ns_setup(NvmeCtrl *n, NvmeNamespace *ns, Error **errp)
{
    if (nvme_ns_check_constraints(ns, errp)) {
        return -1;
    }

    if (nvme_ns_init_blk(n, ns, errp)) {
        return -1;
    }

    if (nvme_ns_init(ns, errp)) {
        return -1;
    }

    if (nvme_register_namespace(n, ns, errp)) {
        return -1;
    }

    return 0;
}

void nvme_ns_drain(NvmeNamespace *ns)
{
    blk_drain(ns->blkconf.blk);
}

void nvme_ns_shutdown(NvmeNamespace *ns)
{
    blk_flush(ns->blkconf.blk);
}

static void nvme_ns_realize(DeviceState *dev, Error **errp)
{
    NvmeNamespace *ns = NVME_NS(dev);
    BusState *s = qdev_get_parent_bus(dev);
    NvmeCtrl *n = NVME(s->parent);
    Error *local_err = NULL;

    if (nvme_ns_setup(n, ns, &local_err)) {
        error_propagate_prepend(errp, local_err,
                                "could not setup namespace: ");
        return;
    }
}

static Property nvme_ns_props[] = {
    DEFINE_BLOCK_PROPERTIES(NvmeNamespace, blkconf),
    DEFINE_PROP_UINT32("nsid", NvmeNamespace, params.nsid, 0),
    DEFINE_PROP_END_OF_LIST(),
};

static void nvme_ns_class_init(ObjectClass *oc, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(oc);

    set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);

    dc->bus_type = TYPE_NVME_BUS;
    dc->realize = nvme_ns_realize;
    device_class_set_props(dc, nvme_ns_props);
    dc->desc = "Virtual NVMe namespace";
}

static void nvme_ns_instance_init(Object *obj)
{
    NvmeNamespace *ns = NVME_NS(obj);
    char *bootindex = g_strdup_printf("/namespace@%d,0", ns->params.nsid);

    device_add_bootindex_property(obj, &ns->bootindex, "bootindex",
                                  bootindex, DEVICE(obj));

    g_free(bootindex);
}

static const TypeInfo nvme_ns_info = {
    .name = TYPE_NVME_NS,
    .parent = TYPE_DEVICE,
    .class_init = nvme_ns_class_init,
    .instance_size = sizeof(NvmeNamespace),
    .instance_init = nvme_ns_instance_init,
};

static void nvme_ns_register_types(void)
{
    type_register_static(&nvme_ns_info);
}

type_init(nvme_ns_register_types)