hw/block/nvme: fix handling of private namespaces

Prior to this patch, if a private nvme-ns device (that is, a namespace
that is not linked to a subsystem) is wired up to an nvme-subsys linked
nvme controller device, the device fails to verify that the namespace id
is unique within the subsystem. NVM Express v1.4b, Section 6.1.6 ("NSID
and Namespace Usage") states that because the device supports Namespace
Management, "NSIDs *shall* be unique within the NVM subsystem".

Additionally, prior to this patch, private namespaces are not known to
the subsystem and the namespace is considered exclusive to the
controller with which it is initially wired up to. However, this is not
the definition of a private namespace; per Section 1.6.33 ("private
namespace"), a private namespace is just a namespace that does not
support multipath I/O or namespace sharing, which means "that it is only
able to be attached to one controller at a time".

Fix this by always allocating namespaces in the subsystem (if one is
linked to the controller), regardless of the shared/private status of
the namespace. Whether or not the namespace is shareable is controlled
by a new `shared` nvme-ns parameter.

Finally, this fix allows the nvme-ns `subsys` parameter to be removed,
since the `shared` parameter now serves the purpose of attaching the
namespace to all controllers in the subsystem upon device realization.
It is invalid to have an nvme-ns namespace device with a linked
subsystem without the parent nvme controller device also being linked to
one and since the nvme-ns devices will unconditionally be "attached" (in
QEMU terms that is) to an nvme controller device through an NvmeBus, the
nvme-ns namespace device can always get a reference to the subsystem of
the controller it is explicitly (using 'bus=' parameter) or implicitly
attaching to.

Fixes: e570768566b3 ("hw/block/nvme: support for shared namespace in subsystem")
Cc: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
Reviewed-by: Gollu Appalanaidu <anaidu.gollu@samsung.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>

1 files changed, 3 insertions, 7 deletions

diff --git a/hw/block/nvme-ns.h b/hw/block/nvme-ns.h
index 82340c4..fb0a41f 100644
--- a/hw/block/nvme-ns.h
+++ b/hw/block/nvme-ns.h
@@ -29,6 +29,7 @@ typedef struct NvmeZone {
 
 typedef struct NvmeNamespaceParams {
     bool     detached;
+    bool     shared;
     uint32_t nsid;
     QemuUUID uuid;
 
@@ -60,8 +61,8 @@ typedef struct NvmeNamespace {
     const uint32_t *iocs;
     uint8_t      csi;
     uint16_t     status;
+    int          attached;
 
-    NvmeSubsystem   *subsys;
     QTAILQ_ENTRY(NvmeNamespace) entry;
 
     NvmeIdNsZoned   *id_ns_zoned;
@@ -99,11 +100,6 @@ static inline uint32_t nvme_nsid(NvmeNamespace *ns)
     return 0;
 }
 
-static inline bool nvme_ns_shared(NvmeNamespace *ns)
-{
-    return !!ns->subsys;
-}
-
 static inline NvmeLBAF *nvme_ns_lbaf(NvmeNamespace *ns)
 {
     NvmeIdNs *id_ns = &ns->id_ns;
@@ -225,7 +221,7 @@ static inline void nvme_aor_dec_active(NvmeNamespace *ns)
 }
 
 void nvme_ns_init_format(NvmeNamespace *ns);
-int nvme_ns_setup(NvmeNamespace *ns, Error **errp);
+int nvme_ns_setup(NvmeCtrl *n, NvmeNamespace *ns, Error **errp);
 void nvme_ns_drain(NvmeNamespace *ns);
 void nvme_ns_shutdown(NvmeNamespace *ns);
 void nvme_ns_cleanup(NvmeNamespace *ns);