Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio, vhost, acpi: features, fixes, tests

ARM ACPI memory hotplug support +
tests for new arm/virt ACPI tables.

Virtio fs support (no migration).
A vhost-user reconnect bugfix.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Tue 15 Oct 2019 22:02:19 BST
# gpg:                using RSA key 281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>" [full]
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream:
  virtio: add vhost-user-fs-pci device
  virtio: add vhost-user-fs base device
  virtio: Add virtio_fs linux headers
  tests/acpi: add expected tables for arm/virt
  tests: document how to update acpi tables
  tests: Add bios tests to arm/virt
  tests: allow empty expected files
  tests/acpi: add empty files
  tests: Update ACPI tables list for upcoming arm/virt tests
  docs/specs: Add ACPI GED documentation
  hw/arm: Use GED for system_powerdown event
  hw/arm: Factor out powerdown notifier from GPIO
  hw/arm/virt-acpi-build: Add PC-DIMM in SRAT
  hw/arm/virt: Enable device memory cold/hot plug with ACPI boot
  hw/arm/virt: Add memory hotplug framework
  hw/acpi: Add ACPI Generic Event Device Support
  hw/acpi: Do not create memory hotplug method when handler is not defined
  hw/acpi: Make ACPI IO address space configurable
  vhost-user: save features if the char dev is closed

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

docs/specs/acpi_hw_reduced_hotplug.rst

@@ -0,0 +1,70 @@
+==================================================
+QEMU and ACPI BIOS Generic Event Device interface
+==================================================
+
+The ACPI *Generic Event Device* (GED) is a HW reduced platform
+specific device introduced in ACPI v6.1 that handles all platform
+events, including the hotplug ones. GED is modelled as a device
+in the namespace with a _HID defined to be ACPI0013. This document
+describes the interface between QEMU and the ACPI BIOS.
+
+GED allows HW reduced platforms to handle interrupts in ACPI ASL
+statements. It follows a very similar approach to the _EVT method
+from GPIO events. All interrupts are listed in  _CRS and the handler
+is written in _EVT method. However, the QEMU implementation uses a
+single interrupt for the GED device, relying on an IO memory region
+to communicate the type of device affected by the interrupt. This way,
+we can support up to 32 events with a unique interrupt.
+
+**Here is an example,**
+
+::
+
+   Device (\_SB.GED)
+   {
+       Name (_HID, "ACPI0013")
+       Name (_UID, Zero)
+       Name (_CRS, ResourceTemplate ()
+       {
+           Interrupt (ResourceConsumer, Edge, ActiveHigh, Exclusive, ,, )
+           {
+               0x00000029,
+           }
+       })
+       OperationRegion (EREG, SystemMemory, 0x09080000, 0x04)
+       Field (EREG, DWordAcc, NoLock, WriteAsZeros)
+       {
+           ESEL,   32
+       }
+       Method (_EVT, 1, Serialized)
+       {
+           Local0 = ESEL // ESEL = IO memory region which specifies the
+                         // device type.
+           If (((Local0 & One) == One))
+           {
+               MethodEvent1()
+           }
+           If ((Local0 & 0x2) == 0x2)
+           {
+               MethodEvent2()
+           }
+           ...
+       }
+   }
+
+GED IO interface (4 byte access)
+--------------------------------
+**read access:**
+
+::
+
+   [0x0-0x3] Event selector bit field (32 bit) set by QEMU.
+
+    bits:
+       0: Memory hotplug event
+       1: System power down event
+    2-31: Reserved
+
+**write_access:**
+
+Nothing is expected to be written into GED IO memory

docs/specs/index.rst

@@ -12,3 +12,4 @@ Contents:
 
    ppc-xive
    ppc-spapr-xive
+   acpi_hw_reduced_hotplug