[Qemu-block] [PATCH 16/16] nvme: support multiple namespaces

[Klaus Birkelund Jensen]

This adds support for multiple namespaces by introducing a new 'nvme-ns'
device model. The nvme device creates a bus named from the device name
('id'). The nvme-ns devices then connect to this and registers
themselves with the nvme device.

This changes how an nvme device is created. Example with two namespaces:

  -drive file=nvme0n1.img,if=none,id=disk1
  -drive file=nvme0n2.img,if=none,id=disk2
  -device nvme,serial=deadbeef,id=nvme0
  -device nvme-ns,drive=disk1,bus=nvme0,nsid=1
  -device nvme-ns,drive=disk2,bus=nvme0,nsid=2

A maximum of 256 namespaces can be configured.

Signed-off-by: Klaus Birkelund Jensen <address@hidden>
---
 hw/block/Makefile.objs |   2 +-
 hw/block/nvme-ns.c     | 139 +++++++++++++++++++++++++++++++++
 hw/block/nvme-ns.h     |  35 +++++++++
 hw/block/nvme.c        | 169 ++++++++++++++++-------------------------
 hw/block/nvme.h        |  29 ++++---
 hw/block/trace-events  |   1 +
 6 files changed, 255 insertions(+), 120 deletions(-)
 create mode 100644 hw/block/nvme-ns.c
 create mode 100644 hw/block/nvme-ns.h

diff --git a/hw/block/Makefile.objs b/hw/block/Makefile.objs
index f5f643f0cc06..d44a2f4b780d 100644
--- a/hw/block/Makefile.objs
+++ b/hw/block/Makefile.objs
@@ -7,7 +7,7 @@ common-obj-$(CONFIG_PFLASH_CFI02) += pflash_cfi02.o
 common-obj-$(CONFIG_XEN) += xen-block.o
 common-obj-$(CONFIG_ECC) += ecc.o
 common-obj-$(CONFIG_ONENAND) += onenand.o
-common-obj-$(CONFIG_NVME_PCI) += nvme.o
+common-obj-$(CONFIG_NVME_PCI) += nvme.o nvme-ns.o
 
 obj-$(CONFIG_SH4) += tc58128.o
 
diff --git a/hw/block/nvme-ns.c b/hw/block/nvme-ns.c
new file mode 100644
index 000000000000..11b594467991
--- /dev/null
+++ b/hw/block/nvme-ns.c
@@ -0,0 +1,139 @@
+#include "qemu/osdep.h"
+#include "qemu/units.h"
+#include "qemu/cutils.h"
+#include "qemu/log.h"
+#include "hw/block/block.h"
+#include "hw/pci/msix.h"
+#include "sysemu/sysemu.h"
+#include "sysemu/block-backend.h"
+#include "qapi/error.h"
+
+#include "hw/qdev-core.h"
+
+#include "nvme.h"
+#include "nvme-ns.h"
+
+static uint64_t nvme_ns_calc_blks(NvmeNamespace *ns)
+{
+    return ns->size / nvme_ns_lbads_bytes(ns);
+}
+
+static void nvme_ns_init_identify(NvmeIdNs *id_ns)
+{
+    id_ns->lbaf[0].ds = BDRV_SECTOR_BITS;
+}
+
+static int nvme_ns_init(NvmeNamespace *ns)
+{
+    uint64_t ns_blks;
+    NvmeIdNs *id_ns = &ns->id_ns;
+
+    nvme_ns_init_identify(id_ns);
+
+    ns_blks = nvme_ns_calc_blks(ns);
+    id_ns->nuse = id_ns->ncap = id_ns->nsze = cpu_to_le64(ns_blks);
+
+    return 0;
+}
+
+static int nvme_ns_init_blk(NvmeNamespace *ns, NvmeIdCtrl *id, Error **errp)
+{
+    blkconf_blocksizes(&ns->conf);
+
+    if (!blkconf_apply_backend_options(&ns->conf,
+        blk_is_read_only(ns->conf.blk), false, errp)) {
+        return 1;
+    }
+
+    ns->size = blk_getlength(ns->conf.blk);
+    if (ns->size < 0) {
+        error_setg_errno(errp, -ns->size, "blk_getlength");
+        return 1;
+    }
+
+    if (!blk_enable_write_cache(ns->conf.blk)) {
+        id->vwc = 0;
+    }
+
+    return 0;
+}
+
+static int nvme_ns_check_constraints(NvmeNamespace *ns, Error **errp)
+{
+    if (!ns->conf.blk) {
+        error_setg(errp, "nvme-ns: block backend not configured");
+        return 1;
+    }
+
+    return 0;
+}
+
+
+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_check_constraints(ns, &local_err)) {
+        error_propagate_prepend(errp, local_err,
+            "nvme_ns_check_constraints: ");
+        return;
+    }
+
+    if (nvme_ns_init_blk(ns, &n->id_ctrl, &local_err)) {
+        error_propagate_prepend(errp, local_err, "nvme_ns_init_blk: ");
+        return;
+    }
+
+    nvme_ns_init(ns);
+    if (nvme_register_namespace(n, ns, &local_err)) {
+        error_propagate_prepend(errp, local_err, "nvme_register_namespace: ");
+        return;
+    }
+}
+
+static Property nvme_ns_props[] = {
+    DEFINE_BLOCK_PROPERTIES(NvmeNamespace, conf),
+    DEFINE_NVME_NS_PROPERTIES(NvmeNamespace, params),
+    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;
+    dc->props = 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->conf.bootindex, "bootindex",
+        bootindex, DEVICE(obj), &error_abort);
+
+    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)
diff --git a/hw/block/nvme-ns.h b/hw/block/nvme-ns.h
new file mode 100644
index 000000000000..f563bb14eceb
--- /dev/null
+++ b/hw/block/nvme-ns.h
@@ -0,0 +1,35 @@
+#ifndef NVME_NS_H
+#define NVME_NS_H
+
+#define TYPE_NVME_NS "nvme-ns"
+#define NVME_NS(obj) \
+    OBJECT_CHECK(NvmeNamespace, (obj), TYPE_NVME_NS)
+
+#define DEFINE_NVME_NS_PROPERTIES(_state, _props) \
+    DEFINE_PROP_UINT32("nsid", _state, _props.nsid, 0)
+
+typedef struct NvmeNamespaceParams {
+    uint32_t nsid;
+} NvmeNamespaceParams;
+
+typedef struct NvmeNamespace {
+    DeviceState parent_obj;
+    BlockConf   conf;
+    int64_t     size;
+
+    NvmeIdNs            id_ns;
+    NvmeNamespaceParams params;
+} NvmeNamespace;
+
+static inline uint8_t nvme_ns_lbads(NvmeNamespace *ns)
+{
+    NvmeIdNs *id = &ns->id_ns;
+    return id->lbaf[NVME_ID_NS_FLBAS_INDEX(id->flbas)].ds;
+}
+
+static inline size_t nvme_ns_lbads_bytes(NvmeNamespace *ns)
+{
+    return 1 << nvme_ns_lbads(ns);
+}
+
+#endif /* NVME_NS_H */
diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index 6bf62952dd13..6448798132d6 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -17,7 +17,8 @@
 /**
  * Usage: add options:
  *     -drive file=<file>,if=none,id=<drive_id>
- *     -device nvme,drive=<drive_id>,serial=<serial>,id=<id[optional]>
+ *     -device nvme,serial=<serial>,id=nvme0
+ *     -device nvme-ns,drive=<drive_id>,bus=nvme0,nsid=1
  *
  * Advanced optional options:
  *
@@ -41,6 +42,7 @@
 
 #include "trace.h"
 #include "nvme.h"
+#include "nvme-ns.h"
 
 #define NVME_MAX_QS PCI_MSIX_FLAGS_QSIZE
 #define NVME_TEMPERATURE 0x143
@@ -848,15 +850,16 @@ static void nvme_rw_cb(void *opaque, int ret)
     NvmeSQueue *sq = req->sq;
     NvmeCtrl *n = sq->ctrl;
     NvmeCQueue *cq = n->cq[sq->cqid];
+    NvmeNamespace *ns = req->ns;
 
     QTAILQ_REMOVE(&req->blk_req_tailq, blk_req, tailq_entry);
 
-    trace_nvme_rw_cb(req->cqe.cid, req->cmd.nsid);
+    trace_nvme_rw_cb(req->cqe.cid, ns->params.nsid);
 
     if (!ret) {
-        block_acct_done(blk_get_stats(n->conf.blk), &blk_req->acct);
+        block_acct_done(blk_get_stats(ns->conf.blk), &blk_req->acct);
     } else {
-        block_acct_failed(blk_get_stats(n->conf.blk), &blk_req->acct);
+        block_acct_failed(blk_get_stats(ns->conf.blk), &blk_req->acct);
         NVME_GUEST_ERR(nvme_err_internal_dev_error, "block request failed: %s",
             strerror(-ret));
         req->status = NVME_INTERNAL_DEV_ERROR | NVME_DNR;
@@ -871,6 +874,7 @@ static void nvme_rw_cb(void *opaque, int ret)
 
 static uint16_t nvme_flush(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
 {
+    NvmeNamespace *ns = req->ns;
     NvmeBlockBackendRequest *blk_req = nvme_blk_req_get(n, req, NULL);
     if (!blk_req) {
         NVME_GUEST_ERR(nvme_err_internal_dev_error, "nvme_blk_req_get: %s",
@@ -878,9 +882,9 @@ static uint16_t nvme_flush(NvmeCtrl *n, NvmeCmd *cmd, 
NvmeRequest *req)
         return NVME_INTERNAL_DEV_ERROR;
     }
 
-    block_acct_start(blk_get_stats(n->conf.blk), &blk_req->acct, 0,
+    block_acct_start(blk_get_stats(ns->conf.blk), &blk_req->acct, 0,
          BLOCK_ACCT_FLUSH);
-    blk_req->aiocb = blk_aio_flush(n->conf.blk, nvme_rw_cb, blk_req);
+    blk_req->aiocb = blk_aio_flush(ns->conf.blk, nvme_rw_cb, blk_req);
 
     QTAILQ_INSERT_TAIL(&req->blk_req_tailq, blk_req, tailq_entry);
 
@@ -890,6 +894,7 @@ static uint16_t nvme_flush(NvmeCtrl *n, NvmeCmd *cmd, 
NvmeRequest *req)
 static uint16_t nvme_write_zeros(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
 {
     NvmeRwCmd *rw = (NvmeRwCmd *)cmd;
+    NvmeNamespace *ns = req->ns;
     NvmeBlockBackendRequest *blk_req;
     const uint8_t lbads = nvme_ns_lbads(req->ns);
     uint64_t slba = le64_to_cpu(rw->slba);
@@ -909,10 +914,10 @@ static uint16_t nvme_write_zeros(NvmeCtrl *n, NvmeCmd 
*cmd, NvmeRequest *req)
         return NVME_INTERNAL_DEV_ERROR;
     }
 
-    block_acct_start(blk_get_stats(n->conf.blk), &blk_req->acct, 0,
+    block_acct_start(blk_get_stats(ns->conf.blk), &blk_req->acct, 0,
         BLOCK_ACCT_WRITE);
 
-    blk_req->aiocb = blk_aio_pwrite_zeroes(n->conf.blk, offset, count,
+    blk_req->aiocb = blk_aio_pwrite_zeroes(ns->conf.blk, offset, count,
         BDRV_REQ_MAY_UNMAP, nvme_rw_cb, blk_req);
 
     QTAILQ_INSERT_TAIL(&req->blk_req_tailq, blk_req, tailq_entry);
@@ -929,7 +934,7 @@ static uint16_t nvme_rw_check_req(NvmeCtrl *n, NvmeCmd 
*cmd, NvmeRequest *req)
     uint32_t data_size = req->nlb << nvme_ns_lbads(ns);
 
     if (unlikely((req->slba + req->nlb) > ns->id_ns.nsze)) {
-        block_acct_invalid(blk_get_stats(n->conf.blk), req->is_write ?
+        block_acct_invalid(blk_get_stats(ns->conf.blk), req->is_write ?
             BLOCK_ACCT_WRITE : BLOCK_ACCT_READ);
         trace_nvme_err_invalid_lba_range(req->slba, req->nlb, ns->id_ns.nsze);
         return NVME_LBA_RANGE | NVME_DNR;
@@ -950,18 +955,19 @@ static void nvme_blk_submit_dma(NvmeCtrl *n, 
NvmeBlockBackendRequest *blk_req,
     BlockCompletionFunc *cb)
 {
     NvmeRequest *req = blk_req->req;
+    NvmeNamespace *ns = req->ns;
 
     if (req->is_write) {
-        dma_acct_start(n->conf.blk, &blk_req->acct, blk_req->qsg,
+        dma_acct_start(ns->conf.blk, &blk_req->acct, blk_req->qsg,
             BLOCK_ACCT_WRITE);
 
-        blk_req->aiocb = dma_blk_write(n->conf.blk, blk_req->qsg,
+        blk_req->aiocb = dma_blk_write(ns->conf.blk, blk_req->qsg,
             blk_req->blk_offset, BDRV_SECTOR_SIZE, cb, blk_req);
     } else {
-        dma_acct_start(n->conf.blk, &blk_req->acct, blk_req->qsg,
+        dma_acct_start(ns->conf.blk, &blk_req->acct, blk_req->qsg,
             BLOCK_ACCT_READ);
 
-        blk_req->aiocb = dma_blk_read(n->conf.blk, blk_req->qsg,
+        blk_req->aiocb = dma_blk_read(ns->conf.blk, blk_req->qsg,
             blk_req->blk_offset, BDRV_SECTOR_SIZE, cb, blk_req);
     }
 }
@@ -970,21 +976,22 @@ static void nvme_blk_submit_cmb(NvmeCtrl *n, 
NvmeBlockBackendRequest *blk_req,
     BlockCompletionFunc *cb)
 {
     NvmeRequest *req = blk_req->req;
+    NvmeNamespace *ns = req->ns;
 
     qemu_iovec_init(&blk_req->iov, blk_req->qsg->nsg);
     dma_to_cmb(n, blk_req->qsg, &blk_req->iov);
 
     if (req->is_write) {
-        block_acct_start(blk_get_stats(n->conf.blk), &blk_req->acct,
+        block_acct_start(blk_get_stats(ns->conf.blk), &blk_req->acct,
             blk_req->iov.size, BLOCK_ACCT_WRITE);
 
-        blk_req->aiocb = blk_aio_pwritev(n->conf.blk, blk_req->blk_offset,
+        blk_req->aiocb = blk_aio_pwritev(ns->conf.blk, blk_req->blk_offset,
             &blk_req->iov, 0, cb, blk_req);
     } else {
-        block_acct_start(blk_get_stats(n->conf.blk), &blk_req->acct,
+        block_acct_start(blk_get_stats(ns->conf.blk), &blk_req->acct,
             blk_req->iov.size, BLOCK_ACCT_READ);
 
-        blk_req->aiocb = blk_aio_preadv(n->conf.blk, blk_req->blk_offset,
+        blk_req->aiocb = blk_aio_preadv(ns->conf.blk, blk_req->blk_offset,
             &blk_req->iov, 0, cb, blk_req);
     }
 }
@@ -1042,7 +1049,8 @@ static uint16_t nvme_io_cmd(NvmeCtrl *n, NvmeCmd *cmd, 
NvmeRequest *req)
         return NVME_INVALID_NSID | NVME_DNR;
     }
 
-    req->ns = &n->namespace;
+    req->ns = n->namespaces[nsid - 1];
+
     switch (cmd->opcode) {
     case NVME_CMD_FLUSH:
         return nvme_flush(n, cmd, req);
@@ -1302,7 +1310,7 @@ static uint16_t nvme_identify_ns(NvmeCtrl *n, NvmeCmd 
*cmd, NvmeRequest *req)
         return NVME_INVALID_NSID | NVME_DNR;
     }
 
-    ns = &n->namespace;
+    ns = n->namespaces[nsid - 1];
 
     return nvme_dma_read(n, (uint8_t *) &ns->id_ns, sizeof(ns->id_ns), cmd,
         req);
@@ -1444,6 +1452,8 @@ static uint16_t nvme_get_feature_timestamp(NvmeCtrl *n, 
NvmeCmd *cmd,
 
 static uint16_t nvme_get_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
 {
+    NvmeNamespace *ns = req->ns;
+
     uint32_t dw10 = le32_to_cpu(cmd->cdw10);
     uint32_t dw11 = le32_to_cpu(cmd->cdw11);
     uint32_t result;
@@ -1464,7 +1474,7 @@ static uint16_t nvme_get_feature(NvmeCtrl *n, NvmeCmd 
*cmd, NvmeRequest *req)
         result = cpu_to_le32(n->features.err_rec);
         break;
     case NVME_VOLATILE_WRITE_CACHE:
-        result = blk_enable_write_cache(n->conf.blk);
+        result = blk_enable_write_cache(ns->conf.blk);
         trace_nvme_getfeat_vwcache(result ? "enabled" : "disabled");
         break;
     case NVME_NUMBER_OF_QUEUES:
@@ -1518,6 +1528,8 @@ static uint16_t nvme_set_feature_timestamp(NvmeCtrl *n, 
NvmeCmd *cmd,
 
 static uint16_t nvme_set_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
 {
+    NvmeNamespace *ns = req->ns;
+
     uint32_t dw10 = le32_to_cpu(cmd->cdw10);
     uint32_t dw11 = le32_to_cpu(cmd->cdw11);
 
@@ -1532,7 +1544,7 @@ static uint16_t nvme_set_feature(NvmeCtrl *n, NvmeCmd 
*cmd, NvmeRequest *req)
         }
         break;
     case NVME_VOLATILE_WRITE_CACHE:
-        blk_set_enable_write_cache(n->conf.blk, dw11 & 1);
+        blk_set_enable_write_cache(ns->conf.blk, dw11 & 1);
         break;
     case NVME_NUMBER_OF_QUEUES:
         if (n->qs_created > 2) {
@@ -1835,7 +1847,9 @@ static void nvme_clear_ctrl(NvmeCtrl *n)
     NvmeAsyncEvent *event;
     int i;
 
-    blk_drain(n->conf.blk);
+    for (int i = 0; i < n->num_namespaces; i++) {
+        blk_drain(n->namespaces[i]->conf.blk);
+    }
 
     for (i = 0; i < n->params.num_queues; i++) {
         if (n->sq[i] != NULL) {
@@ -1858,7 +1872,10 @@ static void nvme_clear_ctrl(NvmeCtrl *n)
         g_free(event);
     }
 
-    blk_flush(n->conf.blk);
+    for (int i = 0; i < n->num_namespaces; i++) {
+        blk_flush(n->namespaces[i]->conf.blk);
+    }
+
     n->bar.cc = 0;
     n->outstanding_aers = 0;
 }
@@ -2280,8 +2297,8 @@ static int nvme_check_constraints(NvmeCtrl *n, Error 
**errp)
 {
     NvmeParams *params = &n->params;
 
-    if (!n->conf.blk) {
-        error_setg(errp, "nvme: block backend not configured");
+    if (!n->parent_obj.qdev.id) {
+        error_setg(errp, "nvme: invalid 'id' parameter");
         return 1;
     }
 
@@ -2298,20 +2315,9 @@ static int nvme_check_constraints(NvmeCtrl *n, Error 
**errp)
     return 0;
 }
 
-static int nvme_init_blk(NvmeCtrl *n, Error **errp)
-{
-    blkconf_blocksizes(&n->conf);
-    if (!blkconf_apply_backend_options(&n->conf, blk_is_read_only(n->conf.blk),
-        false, errp)) {
-        return 1;
-    }
-
-    return 0;
-}
-
 static void nvme_init_state(NvmeCtrl *n)
 {
-    n->num_namespaces = 1;
+    n->num_namespaces = 0;
     n->reg_size = pow2ceil(0x1004 + 2 * (n->params.num_queues + 1) * 4);
     n->starttime_ms = qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL);
     n->sq = g_new0(NvmeSQueue *, n->params.num_queues);
@@ -2404,11 +2410,7 @@ static void nvme_init_ctrl(NvmeCtrl *n)
     id->cqes = (0x4 << 4) | 0x4;
     id->nn = cpu_to_le32(n->num_namespaces);
     id->oncs = cpu_to_le16(NVME_ONCS_WRITE_ZEROS | NVME_ONCS_TIMESTAMP);
-
-    if (blk_enable_write_cache(n->conf.blk)) {
-        id->vwc = 1;
-    }
-
+    id->vwc = 1;
     id->sgls = cpu_to_le32(0x1);
 
     strcpy((char *) id->subnqn, "nqn.2014-08.org.nvmexpress:uuid:");
@@ -2430,52 +2432,26 @@ static void nvme_init_ctrl(NvmeCtrl *n)
     n->bar.intmc = n->bar.intms = 0;
 }
 
-static uint64_t nvme_ns_calc_blks(NvmeCtrl *n, NvmeNamespace *ns)
-{
-    return n->ns_size / nvme_ns_lbads_bytes(ns);
-}
-
-static void nvme_ns_init_identify(NvmeCtrl *n, NvmeIdNs *id_ns)
-{
-    id_ns->lbaf[0].ds = BDRV_SECTOR_BITS;
-    id_ns->ncap  = id_ns->nuse = id_ns->nsze =
-        cpu_to_le64(n->ns_size >>
-            id_ns->lbaf[NVME_ID_NS_FLBAS_INDEX(id_ns->flbas)].ds);
-}
-
-static int nvme_init_namespace(NvmeCtrl *n, NvmeNamespace *ns, Error **errp)
-{
-    uint64_t ns_blks;
-    NvmeIdNs *id_ns = &ns->id_ns;
-
-    nvme_ns_init_identify(n, id_ns);
-
-    ns_blks = nvme_ns_calc_blks(n, ns);
-    id_ns->nuse = id_ns->ncap = id_ns->nsze = cpu_to_le64(ns_blks);
-
-    return 0;
-}
-
-static int nvme_init_namespaces(NvmeCtrl *n, Error **errp)
+int nvme_register_namespace(NvmeCtrl *n, NvmeNamespace *ns, Error **errp)
 {
-    int64_t bs_size;
-    Error *local_err = NULL;
-    NvmeNamespace *ns = &n->namespace;
+    uint32_t nsid = ns->params.nsid;
 
-    bs_size = blk_getlength(n->conf.blk);
-    if (bs_size < 0) {
-        error_setg_errno(errp, -bs_size, "blk_getlength");
+    if (nsid == 0 || nsid > NVME_MAX_NAMESPACES) {
+        error_setg(errp, "invalid namespace id");
         return 1;
     }
 
-    n->ns_size = bs_size / (uint64_t) n->num_namespaces;
-
-    if (nvme_init_namespace(n, ns, &local_err)) {
-        error_propagate_prepend(errp, local_err,
-            "nvme_init_namespace: ");
+    if (n->namespaces[nsid - 1]) {
+        error_setg(errp, "namespace ids must be unique");
         return 1;
     }
 
+    trace_nvme_register_namespace(nsid);
+
+    n->namespaces[nsid - 1] = ns;
+    n->num_namespaces++;
+    n->id_ctrl.nn++;
+
     return 0;
 }
 
@@ -2489,19 +2465,10 @@ static void nvme_realize(PCIDevice *pci_dev, Error 
**errp)
         return;
     }
 
-    nvme_init_state(n);
-
-    if (nvme_init_blk(n, &local_err)) {
-        error_propagate_prepend(errp, local_err, "nvme_init_blk: ");
-        return;
-    }
-
-    if (nvme_init_namespaces(n, &local_err)) {
-        error_propagate_prepend(errp, local_err,
-            "nvme_init_namespaces: ");
-        return;
-    }
+    qbus_create_inplace(&n->bus, sizeof(NvmeBus), TYPE_NVME_BUS,
+        &pci_dev->qdev, n->parent_obj.qdev.id);
 
+    nvme_init_state(n);
     nvme_init_pci(n, pci_dev);
     nvme_init_ctrl(n);
 }
@@ -2524,7 +2491,6 @@ static void nvme_exit(PCIDevice *pci_dev)
 }
 
 static Property nvme_props[] = {
-    DEFINE_BLOCK_PROPERTIES(NvmeCtrl, conf),
     DEFINE_NVME_PROPERTIES(NvmeCtrl, params),
     DEFINE_PROP_END_OF_LIST(),
 };
@@ -2552,30 +2518,27 @@ static void nvme_class_init(ObjectClass *oc, void *data)
     dc->vmsd = &nvme_vmstate;
 }
 
-static void nvme_instance_init(Object *obj)
-{
-    NvmeCtrl *s = NVME(obj);
-
-    device_add_bootindex_property(obj, &s->conf.bootindex,
-                                  "bootindex", "/namespace@1,0",
-                                  DEVICE(obj), &error_abort);
-}
-
 static const TypeInfo nvme_info = {
     .name          = TYPE_NVME,
     .parent        = TYPE_PCI_DEVICE,
     .instance_size = sizeof(NvmeCtrl),
     .class_init    = nvme_class_init,
-    .instance_init = nvme_instance_init,
     .interfaces = (InterfaceInfo[]) {
         { INTERFACE_PCIE_DEVICE },
         { }
     },
 };
 
+static const TypeInfo nvme_bus_info = {
+    .name = TYPE_NVME_BUS,
+    .parent = TYPE_BUS,
+    .instance_size = sizeof(NvmeBus),
+};
+
 static void nvme_register_types(void)
 {
     type_register_static(&nvme_info);
+    type_register_static(&nvme_bus_info);
 }
 
 type_init(nvme_register_types)
diff --git a/hw/block/nvme.h b/hw/block/nvme.h
index 1d52b183d263..9aff5c82a51b 100644
--- a/hw/block/nvme.h
+++ b/hw/block/nvme.h
@@ -2,6 +2,9 @@
 #define HW_NVME_H
 
 #include "block/nvme.h"
+#include "nvme-ns.h"
+
+#define NVME_MAX_NAMESPACES 256
 
 #define DEFINE_NVME_PROPERTIES(_state, _props) \
     DEFINE_PROP_STRING("serial", _state, _props.serial), \
@@ -86,9 +89,12 @@ typedef struct NvmeCQueue {
     QTAILQ_HEAD(, NvmeRequest) req_list;
 } NvmeCQueue;
 
-typedef struct NvmeNamespace {
-    NvmeIdNs        id_ns;
-} NvmeNamespace;
+#define TYPE_NVME_BUS "nvme-bus"
+#define NVME_BUS(obj) OBJECT_CHECK(NvmeBus, (obj), TYPE_NVME_BUS)
+
+typedef struct NvmeBus {
+    BusState parent_bus;
+} NvmeBus;
 
 #define TYPE_NVME "nvme"
 #define NVME(obj) \
@@ -99,7 +105,6 @@ typedef struct NvmeCtrl {
     MemoryRegion iomem;
     MemoryRegion ctrl_mem;
     NvmeBar      bar;
-    BlockConf    conf;
     NvmeParams   params;
 
     uint64_t    starttime_ms;
@@ -112,7 +117,6 @@ typedef struct NvmeCtrl {
     uint32_t    reg_size;
     uint32_t    num_namespaces;
     uint32_t    max_q_ents;
-    uint64_t    ns_size;
     uint8_t     outstanding_aers;
     uint32_t    cmbsz;
     uint32_t    cmbloc;
@@ -128,13 +132,15 @@ typedef struct NvmeCtrl {
     QSIMPLEQ_HEAD(, NvmeAsyncEvent) aer_queue;
 
     NvmeErrorLog    *elpes;
-    NvmeNamespace   namespace;
+    NvmeNamespace   *namespaces[NVME_MAX_NAMESPACES];
     NvmeSQueue      **sq;
     NvmeCQueue      **cq;
     NvmeSQueue      admin_sq;
     NvmeCQueue      admin_cq;
     NvmeFeatureVal  features;
     NvmeIdCtrl      id_ctrl;
+
+    NvmeBus bus;
 } NvmeCtrl;
 
 static inline bool nvme_rw_is_write(NvmeRequest *req)
@@ -148,15 +154,6 @@ static inline bool nvme_is_error(uint16_t status, uint16_t 
err)
     return (status & 0xfff) == err;
 }
 
-static inline uint8_t nvme_ns_lbads(NvmeNamespace *ns)
-{
-    NvmeIdNs *id = &ns->id_ns;
-    return id->lbaf[NVME_ID_NS_FLBAS_INDEX(id->flbas)].ds;
-}
-
-static inline size_t nvme_ns_lbads_bytes(NvmeNamespace *ns)
-{
-    return 1 << nvme_ns_lbads(ns);
-}
+int nvme_register_namespace(NvmeCtrl *n, NvmeNamespace *ns, Error **errp);
 
 #endif /* HW_NVME_H */
diff --git a/hw/block/trace-events b/hw/block/trace-events
index b239e92294e4..0809c248aa54 100644
--- a/hw/block/trace-events
+++ b/hw/block/trace-events
@@ -29,6 +29,7 @@ hd_geometry_guess(void *blk, uint32_t cyls, uint32_t heads, 
uint32_t secs, int t
 
 # nvme.c
 # nvme traces for successful events
+nvme_register_namespace(uint32_t nsid) "nsid %"PRIu32""
 nvme_irq_msix(uint32_t vector) "raising MSI-X IRQ vector %u"
 nvme_irq_pin(void) "pulsing IRQ pin"
 nvme_irq_masked(void) "IRQ is masked"
-- 
2.20.1