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  1. 03 7月, 2020 2 次提交
    • D
      virtio-pci: Proxy for virtio-mem · 0b9a2443
      由 David Hildenbrand 提交于 
      Let's add a proxy for virtio-mem, make it a memory device, and
pass-through the properties.
Reviewed-by: NPankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Message-Id: <20200626072248.78761-12-david@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
      0b9a2443
    • D
      virtio-mem: Paravirtualized memory hot(un)plug · 910b2576
      由 David Hildenbrand 提交于 
      This is the very basic/initial version of virtio-mem. An introduction to
virtio-mem can be found in the Linux kernel driver [1]. While it can be
used in the current state for hotplug of a smaller amount of memory, it
will heavily benefit from resizeable memory regions in the future.

Each virtio-mem device manages a memory region (provided via a memory
backend). After requested by the hypervisor ("requested-size"), the
guest can try to plug/unplug blocks of memory within that region, in order
to reach the requested size. Initially, and after a reboot, all memory is
unplugged (except in special cases - reboot during postcopy).

The guest may only try to plug/unplug blocks of memory within the usable
region size. The usable region size is a little bigger than the
requested size, to give the device driver some flexibility. The usable
region size will only grow, except on reboots or when all memory is
requested to get unplugged. The guest can never plug more memory than
requested. Unplugged memory will get zapped/discarded, similar to in a
balloon device.

The block size is variable, however, it is always chosen in a way such that
THP splits are avoided (e.g., 2MB). The state of each block
(plugged/unplugged) is tracked in a bitmap.

As virtio-mem devices (e.g., virtio-mem-pci) will be memory devices, we now
expose "VirtioMEMDeviceInfo" via "query-memory-devices".

--------------------------------------------------------------------------

There are two important follow-up items that are in the works:
1. Resizeable memory regions: Use resizeable allocations/RAM blocks to
   grow/shrink along with the usable region size. This avoids creating
   initially very big VMAs, RAM blocks, and KVM slots.
2. Protection of unplugged memory: Make sure the gust cannot actually
   make use of unplugged memory.

Other follow-up items that are in the works:
1. Exclude unplugged memory during migration (via precopy notifier).
2. Handle remapping of memory.
3. Support for other architectures.

--------------------------------------------------------------------------

Example usage (virtio-mem-pci is introduced in follow-up patches):

Start QEMU with two virtio-mem devices (one per NUMA node):
 $ qemu-system-x86_64 -m 4G,maxmem=20G \
  -smp sockets=2,cores=2 \
  -numa node,nodeid=0,cpus=0-1 -numa node,nodeid=1,cpus=2-3 \
  [...]
  -object memory-backend-ram,id=mem0,size=8G \
  -device virtio-mem-pci,id=vm0,memdev=mem0,node=0,requested-size=0M \
  -object memory-backend-ram,id=mem1,size=8G \
  -device virtio-mem-pci,id=vm1,memdev=mem1,node=1,requested-size=1G

Query the configuration:
 (qemu) info memory-devices
 Memory device [virtio-mem]: "vm0"
   memaddr: 0x140000000
   node: 0
   requested-size: 0
   size: 0
   max-size: 8589934592
   block-size: 2097152
   memdev: /objects/mem0
 Memory device [virtio-mem]: "vm1"
   memaddr: 0x340000000
   node: 1
   requested-size: 1073741824
   size: 1073741824
   max-size: 8589934592
   block-size: 2097152
   memdev: /objects/mem1

Add some memory to node 0:
 (qemu) qom-set vm0 requested-size 500M

Remove some memory from node 1:
 (qemu) qom-set vm1 requested-size 200M

Query the configuration again:
 (qemu) info memory-devices
 Memory device [virtio-mem]: "vm0"
   memaddr: 0x140000000
   node: 0
   requested-size: 524288000
   size: 524288000
   max-size: 8589934592
   block-size: 2097152
   memdev: /objects/mem0
 Memory device [virtio-mem]: "vm1"
   memaddr: 0x340000000
   node: 1
   requested-size: 209715200
   size: 209715200
   max-size: 8589934592
   block-size: 2097152
   memdev: /objects/mem1

[1] https://lkml.kernel.org/r/20200311171422.10484-1-david@redhat.com

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Eric Blake <eblake@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Message-Id: <20200626072248.78761-11-david@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
      910b2576
  3. 12 6月, 2020 3 次提交
  5. 27 2月, 2020 2 次提交
  7. 18 12月, 2019 1 次提交
  9. 06 10月, 2019 2 次提交
  11. 05 7月, 2019 1 次提交
    • P
      virtio-pci: Proxy for virtio-pmem · adf0748a
      由 Pankaj Gupta 提交于 
      We need a proxy device for virtio-pmem, and this device has to be the
actual memory device so we can cleanly hotplug it.

Forward memory device class functions either to the actual device or use
properties of the virtio-pmem device to implement these in the proxy.

virtio-pmem will only be compiled for selected, supported architectures
(that can deal with virtio/pci devices being memory devices). An
architecture that is prepared for that can simply enable
CONFIG_VIRTIO_PMEM to make it work.

As not all architectures support memory devices (and CONFIG_VIRTIO_PMEM
will be enabled per supported architecture), we have to move the PCI proxy
to a separate file.
Signed-off-by: NPankaj Gupta <pagupta@redhat.com>
[ split up patches, memory-device changes, move pci proxy]
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Message-Id: <20190619094907.10131-5-pagupta@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
      adf0748a
  13. 03 7月, 2019 1 次提交
    • P
      virtio-pmem: add virtio device · 5f503cd9
      由 Pankaj Gupta 提交于 
      This is the implementation of virtio-pmem device. Support will require
machine changes for the architectures that will support it, so it will
not yet be compiled. It can be unlocked with VIRTIO_PMEM_SUPPORTED per
machine and disabled globally via VIRTIO_PMEM.

We cannot use the "addr" property as that is already used e.g. for
virtio-pci/pci devices. And we will have e.g. virtio-pmem-pci as a proxy.
So we have to choose a different one (unfortunately). "memaddr" it is.
That name should ideally be used by all other virtio-* based memory
devices in the future.
    -device virtio-pmem-pci,id=p0,bus=bux0,addr=0x01,memaddr=0x1000000...
Acked-by: NMarkus Armbruster <armbru@redhat.com>
[ QAPI bits ]
Signed-off-by: NPankaj Gupta <pagupta@redhat.com>
[ MemoryDevice/MemoryRegion changes, cleanups, addr property "memaddr",
  split up patches, unplug handler ]
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Message-Id: <20190619094907.10131-2-pagupta@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: NCornelia Huck <cohuck@redhat.com>
      5f503cd9
  15. 10 5月, 2019 1 次提交
    • M
      Add vhost-user-input-pci · 9c4d05b7
      由 Marc-André Lureau 提交于 
      Add a new virtio-input device, which connects to a vhost-user
backend.

Instead of reading configuration directly from an input device /
evdev (like virtio-input-host), it reads it over vhost-user protocol
with {SET,GET}_CONFIG messages. The vhost-user-backend handles the
queues & events setup.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20190503130034.24916-5-marcandre.lureau@redhat.com

[ kraxel: drop -{non-,}transitional variants ]
[ kraxel: fix "make check" on !linux ]
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
      9c4d05b7
  17. 08 3月, 2019 1 次提交
  19. 22 2月, 2019 2 次提交
  21. 05 2月, 2019 1 次提交
  23. 18 1月, 2019 13 次提交
  25. 01 6月, 2018 1 次提交
  27. 25 5月, 2018 1 次提交
  29. 17 1月, 2017 1 次提交
  31. 02 11月, 2016 2 次提交
  33. 10 9月, 2016 1 次提交
  35. 25 2月, 2016 1 次提交
  37. 16 2月, 2015 1 次提交
  39. 22 9月, 2014 1 次提交
  41. 19 6月, 2014 1 次提交
    • N
      Add vhost-user as a vhost backend. · 5f6f6664
      由 Nikolay Nikolaev 提交于 
      The initialization takes a chardev backed by a unix domain socket.
It should implement qemu_fe_set_msgfds in order to be able to pass
file descriptors to the remote process.

Each ioctl request of vhost-kernel has a vhost-user message equivalent,
which is sent over the control socket.

The general approach is to copy the data from the supplied argument
pointer to a designated field in the message. If a file descriptor is
to be passed it will be placed in the fds array for inclusion in
the sendmsg control header.

VHOST_SET_MEM_TABLE ignores the supplied vhost_memory structure and scans
the global ram_list for ram blocks with a valid fd field set. This would
be set when the '-object memory-file' option with share=on property is used.
Signed-off-by: NAntonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: NNikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
      5f6f6664