hw/block/nvme: support multiple namespaces

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

The drive property is kept on the nvme device to keep the change
backward compatible, but the property is now optional. Specifying a
drive for the nvme device will always create the namespace with nsid 1.

Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>

1 files changed, 74 insertions, 0 deletions

diff --git a/hw/block/nvme-ns.h b/hw/block/nvme-ns.h
new file mode 100644
index 0000000000..83734f4606
--- /dev/null
+++ b/hw/block/nvme-ns.h
@@ -0,0 +1,74 @@
+/*
+ * 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.
+ *
+ */
+
+#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)
+
+typedef struct NvmeNamespaceParams {
+    uint32_t nsid;
+} NvmeNamespaceParams;
+
+typedef struct NvmeNamespace {
+    DeviceState  parent_obj;
+    BlockConf    blkconf;
+    int32_t      bootindex;
+    int64_t      size;
+    NvmeIdNs     id_ns;
+
+    NvmeNamespaceParams params;
+} NvmeNamespace;
+
+static inline uint32_t nvme_nsid(NvmeNamespace *ns)
+{
+    if (ns) {
+        return ns->params.nsid;
+    }
+
+    return -1;
+}
+
+static inline NvmeLBAF *nvme_ns_lbaf(NvmeNamespace *ns)
+{
+    NvmeIdNs *id_ns = &ns->id_ns;
+    return &id_ns->lbaf[NVME_ID_NS_FLBAS_INDEX(id_ns->flbas)];
+}
+
+static inline uint8_t nvme_ns_lbads(NvmeNamespace *ns)
+{
+    return nvme_ns_lbaf(ns)->ds;
+}
+
+/* calculate the number of LBAs that the namespace can accomodate */
+static inline uint64_t nvme_ns_nlbas(NvmeNamespace *ns)
+{
+    return ns->size >> nvme_ns_lbads(ns);
+}
+
+/* convert an LBA to the equivalent in bytes */
+static inline size_t nvme_l2b(NvmeNamespace *ns, uint64_t lba)
+{
+    return lba << nvme_ns_lbads(ns);
+}
+
+typedef struct NvmeCtrl NvmeCtrl;
+
+int nvme_ns_setup(NvmeCtrl *n, NvmeNamespace *ns, Error **errp);
+void nvme_ns_drain(NvmeNamespace *ns);
+void nvme_ns_flush(NvmeNamespace *ns);
+
+#endif /* NVME_NS_H */