hw/cxl/events: Add qmp interfaces to add/release dynamic capacity extents

To simulate FM functionalities for initiating Dynamic Capacity Add
(Opcode 5604h) and Dynamic Capacity Release (Opcode 5605h) as in CXL spec
r3.1 7.6.7.6.5 and 7.6.7.6.6, we implemented two QMP interfaces to issue
add/release dynamic capacity extents requests.

With the change, we allow to release an extent only when its DPA range
is contained by a single accepted extent in the device. That is to say,
extent superset release is not supported yet.

1. Add dynamic capacity extents:

For example, the command to add two continuous extents (each 128MiB long)
to region 0 (starting at DPA offset 0) looks like below:

{ "execute": "qmp_capabilities" }

{ "execute": "cxl-add-dynamic-capacity",
  "arguments": {
      "path": "/machine/peripheral/cxl-dcd0",
      "host-id": 0,
      "selection-policy": "prescriptive",
      "region": 0,
      "extents": [
      {
          "offset": 0,
          "len": 134217728
      },
      {
          "offset": 134217728,
          "len": 134217728
      }
      ]
  }
}

2. Release dynamic capacity extents:

For example, the command to release an extent of size 128MiB from region 0
(DPA offset 128MiB) looks like below:

{ "execute": "cxl-release-dynamic-capacity",
  "arguments": {
      "path": "/machine/peripheral/cxl-dcd0",
      "host-id": 0,
      "removal-policy":"prescriptive",
      "region": 0,
      "extents": [
      {
          "offset": 134217728,
          "len": 134217728
      }
      ]
  }
}

Tested-by: Svetly Todorov <svetly.todorov@memverge.com>
Reviewed-by: Gregory Price <gregory.price@memverge.com>
Signed-off-by: Fan Ni <fan.ni@samsung.com>
Message-Id: <20240523174651.1089554-12-nifan.cxl@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 143 insertions, 0 deletions

diff --git a/qapi/cxl.json b/qapi/cxl.json
index 4281726dec..57d9f82014 100644
--- a/qapi/cxl.json
+++ b/qapi/cxl.json
@@ -361,3 +361,146 @@
 ##
 {'command': 'cxl-inject-correctable-error',
  'data': {'path': 'str', 'type': 'CxlCorErrorType'}}
+
+##
+# @CXLDynamicCapacityExtent:
+#
+# A single dynamic capacity extent
+#
+# @offset: The offset (in bytes) to the start of the region
+#     where the extent belongs to.
+#
+# @len: The length of the extent in bytes.
+#
+# Since: 9.1
+##
+{ 'struct': 'CXLDynamicCapacityExtent',
+  'data': {
+      'offset':'uint64',
+      'len': 'uint64'
+  }
+}
+
+##
+# @CXLExtSelPolicy:
+#
+# The policy to use for selecting which extents comprise the added
+# capacity, as defined in cxl spec r3.1 Table 7-70.
+#
+# @free: 0h = Free
+#
+# @contiguous: 1h = Continuous
+#
+# @prescriptive: 2h = Prescriptive
+#
+# @enable-shared-access: 3h = Enable Shared Access
+#
+# Since: 9.1
+##
+{ 'enum': 'CXLExtSelPolicy',
+  'data': ['free',
+           'contiguous',
+           'prescriptive',
+           'enable-shared-access']
+}
+
+##
+# @cxl-add-dynamic-capacity:
+#
+# Command to initiate to add dynamic capacity extents to a host.  It
+# simulates operations defined in cxl spec r3.1 7.6.7.6.5.
+#
+# @path: CXL DCD canonical QOM path.
+#
+# @host-id: The "Host ID" field as defined in cxl spec r3.1
+#     Table 7-70.
+#
+# @selection-policy: The "Selection Policy" bits as defined in
+#     cxl spec r3.1 Table 7-70.  It specifies the policy to use for
+#     selecting which extents comprise the added capacity.
+#
+# @region: The "Region Number" field as defined in cxl spec r3.1
+#     Table 7-70.  The dynamic capacity region where the capacity
+#     is being added.  Valid range is from 0-7.
+#
+# @tag: The "Tag" field as defined in cxl spec r3.1 Table 7-70.
+#
+# @extents: The "Extent List" field as defined in cxl spec r3.1
+#     Table 7-70.
+#
+# Since : 9.1
+##
+{ 'command': 'cxl-add-dynamic-capacity',
+  'data': { 'path': 'str',
+            'host-id': 'uint16',
+            'selection-policy': 'CXLExtSelPolicy',
+            'region': 'uint8',
+            '*tag': 'str',
+            'extents': [ 'CXLDynamicCapacityExtent' ]
+           }
+}
+
+##
+# @CXLExtRemovalPolicy:
+#
+# The policy to use for selecting which extents comprise the released
+# capacity, defined in the "Flags" field in cxl spec r3.1 Table 7-71.
+#
+# @tag-based: value = 0h.  Extents are selected by the device based
+#     on tag, with no requirement for contiguous extents.
+#
+# @prescriptive: value = 1h.  Extent list of capacity to release is
+#     included in the request payload.
+#
+# Since: 9.1
+##
+{ 'enum': 'CXLExtRemovalPolicy',
+  'data': ['tag-based',
+           'prescriptive']
+}
+
+##
+# @cxl-release-dynamic-capacity:
+#
+# Command to initiate to release dynamic capacity extents from a
+# host.  It simulates operations defined in cxl spec r3.1 7.6.7.6.6.
+#
+# @path: CXL DCD canonical QOM path.
+#
+# @host-id: The "Host ID" field as defined in cxl spec r3.1
+#     Table 7-71.
+#
+# @removal-policy: Bit[3:0] of the "Flags" field as defined in cxl
+#     spec r3.1 Table 7-71.
+#
+# @forced-removal: Bit[4] of the "Flags" field in cxl spec r3.1
+#     Table 7-71.  When set, device does not wait for a Release
+#     Dynamic Capacity command from the host.  Host immediately
+#     loses access to released capacity.
+#
+# @sanitize-on-release: Bit[5] of the "Flags" field in cxl spec r3.1
+#     Table 7-71.  When set, device should sanitize all released
+#     capacity as a result of this request.
+#
+# @region: The "Region Number" field as defined in cxl spec r3.1
+#     Table 7-71.  The dynamic capacity region where the capacity
+#     is being added.  Valid range is from 0-7.
+#
+# @tag: The "Tag" field as defined in cxl spec r3.1 Table 7-71.
+#
+# @extents: The "Extent List" field as defined in cxl spec r3.1
+#     Table 7-71.
+#
+# Since : 9.1
+##
+{ 'command': 'cxl-release-dynamic-capacity',
+  'data': { 'path': 'str',
+            'host-id': 'uint16',
+            'removal-policy': 'CXLExtRemovalPolicy',
+            '*forced-removal': 'bool',
+            '*sanitize-on-release': 'bool',
+            'region': 'uint8',
+            '*tag': 'str',
+            'extents': [ 'CXLDynamicCapacityExtent' ]
+           }
+}