Skip to content

Q
qemu

openeuler / qemu

通知 10
Star 0
Fork 0
Q
qemu
切换分支/标签
  1. 21 9月, 2013 1 次提交
    • P
      virtio-blk: do not relay a previous driver's WCE configuration to the current · ef5bc962
      由 Paolo Bonzini 提交于 
      The following sequence happens:
- the SeaBIOS virtio-blk driver does not support the WCE feature, which
causes QEMU to disable writeback caching

- the Linux virtio-blk driver resets the device, finds WCE is available
but writeback caching is disabled; tells block layer to not send cache
flush commands

- the Linux virtio-blk driver sets the DRIVER_OK bit, which causes
writeback caching to be re-enabled, but the Linux virtio-blk driver does
not know of this side effect and cache flushes remain disabled

The bug is at the third step.  If the guest does know about CONFIG_WCE,
QEMU should ignore the WCE feature's state.  The guest will control the
cache mode solely using configuration space.  This change makes Linux
do flushes correctly, but Linux will keep SeaBIOS's writethrough mode.

Hence, whenever the guest is reset, the cache mode of the disk should
be reset to whatever was specified in the "-drive" option.  With this
change, the Linux virtio-blk driver finds that writeback caching is
enabled, and tells the block layer to send cache flush commands
appropriately.

Reported-by: Rusty Russell <rusty@au1.ibm.com
Cc: qemu-stable@nongnu.org
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
      ef5bc962
  3. 29 7月, 2013 2 次提交
  5. 25 4月, 2013 2 次提交
  7. 12 4月, 2013 1 次提交
  9. 09 4月, 2013 2 次提交
  11. 19 3月, 2013 7 次提交
  13. 04 3月, 2013 1 次提交
  15. 01 3月, 2013 1 次提交
    • P
      hw: include hw header files with full paths · 83c9f4ca
      由 Paolo Bonzini 提交于 
      Done with this script:

cd hw
for i in `find . -name '*.h' | sed 's/^..//'`; do
  echo '\,^#.*include.*["<]'$i'[">], s,'$i',hw/&,'
done | sed -i -f - `find . -type f`

This is so that paths remain valid as files are moved.

Instead, files in hw/dataplane are referenced with the relative path.
We know they are not going to move to include/, and they are the only
include files that are in subdirectories _and_ move.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      83c9f4ca
  17. 18 1月, 2013 1 次提交
    • S
      dataplane: support viostor virtio-pci status bit setting · cf139388
      由 Stefan Hajnoczi 提交于 
      The viostor virtio-blk driver for Windows does not use the
VIRTIO_CONFIG_S_DRIVER bit.  It only sets the VIRTIO_CONFIG_S_DRIVER_OK
bit.

The viostor driver refreshes the virtio-pci status byte sometimes while
the guest is running.  We misinterpret 0x4 (VIRTIO_CONFIG_S_DRIVER_OK)
as an indication that virtio-blk-data-plane should be stopped since 0x2
(VIRTIO_CONFIG_S_DRIVER) is missing.  The result is that the device
becomes unresponsive.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
      cf139388
  19. 02 1月, 2013 3 次提交
    • A
      virtio-blk: Return UNSUPP for unknown request types · 9e72c450
      由 Alexey Zaytsev 提交于 
      Currently, all unknown requests are treated as VIRTIO_BLK_T_IN
Signed-off-by: NAlexey Zaytsev <alexey.zaytsev@gmail.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
      9e72c450
    • S
      virtio-blk: add x-data-plane=on|off performance feature · 392808b4
      由 Stefan Hajnoczi 提交于 
      The virtio-blk-data-plane feature is easy to integrate into
hw/virtio-blk.c.  The data plane can be started and stopped similar to
vhost-net.

Users can take advantage of the virtio-blk-data-plane feature using the
new -device virtio-blk-pci,x-data-plane=on property.

The x-data-plane name was chosen because at this stage the feature is
experimental and likely to see changes in the future.

If the VM configuration does not support virtio-blk-data-plane an error
message is printed.  Although we could fall back to regular virtio-blk,
I prefer the explicit approach since it prompts the user to fix their
configuration if they want the performance benefit of
virtio-blk-data-plane.

Limitations:
 * Only format=raw is supported
 * Live migration is not supported
 * Block jobs, hot unplug, and other operations fail with -EBUSY
 * I/O throttling limits are ignored
 * Only Linux hosts are supported due to Linux AIO usage
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
      392808b4
    • S
      virtio-blk: restore VirtIOBlkConf->config_wce flag · 8a873ba7
      由 Stefan Hajnoczi 提交于 
      Two slightly different versions of a patch to conditionally set
VIRTIO_BLK_F_CONFIG_WCE through the "config-wce" qdev property have been
applied (ea776abc and eec7f96c).  David Gibson
<david@gibson.dropbear.id.au> noticed that the "config-wce"
property is broken as a result and fixed it recently.

The fix sets the host_features VIRTIO_BLK_F_CONFIG_WCE bit from a qdev
property.  Unfortunately, the virtio device then has no chance to test
for the presence of the feature bit during virtio_blk_init().

Therefore, reinstate the VirtIOBlkConf->config_wce flag.  Drop the
duplicate qdev property to set the host_features bit.  The
VirtIOBlkConf->config_wce flag will be used by virtio-blk-data-plane in
a later patch.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
      8a873ba7
  21. 19 12月, 2012 2 次提交
  23. 29 9月, 2012 4 次提交
  25. 22 8月, 2012 1 次提交
    • S
      virtio-blk: hide VIRTIO_BLK_F_CONFIG_WCE from old machine types · ea776abc
      由 Stefan Hajnoczi 提交于 
      QEMU has a policy of keeping a stable guest device ABI.  When new guest device
features are introduced they must not change hardware info seen by existing
guests.  This is important because operating systems or applications may
"fingerprint" the hardware and refuse to run when the hardware changes.  To
always get the latest guest device ABI, run with x86 machine type "pc".

This patch hides the new VIRTIO_BLK_F_CONFIG_WCE virtio feature bit from
existing machine types.  Only pc-1.2 and later will expose this feature
by default.

For more info on the VIRTIO_BLK_F_CONFIG_WCE feature bit, see:

  commit 13e3dce0
  Author: Paolo Bonzini <pbonzini@redhat.com>
  Date:   Thu Aug 9 16:07:19 2012 +0200

      virtio-blk: support VIRTIO_BLK_F_CONFIG_WCE

      Also rename VIRTIO_BLK_F_WCACHE to VIRTIO_BLK_F_WCE for consistency with
      the spec.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Anthony Liguori <aliguori@us.ibm.com> reported:

  This broke qemu-test because it changed the pc-1.0 machine type:

  Setting guest RANDOM seed to 47167
  *** Running tests ***
  Running test /tests/finger-print.sh...		OK
  --- fingerprints/pc-1.0.x86_64	2011-12-18 13:08:40.000000000 -0600
  +++ fingerprint.txt	2012-08-12 13:30:48.000000000 -0500
  @@ -55,7 +55,7 @@
   /sys/bus/pci/devices/0000:00:06.0/subsystem_device=0x0002
   /sys/bus/pci/devices/0000:00:06.0/class=0x010000
   /sys/bus/pci/devices/0000:00:06.0/revision=0x00
  -/sys/bus/pci/devices/0000:00:06.0/virtio/host-features=0x710006d4
  +/sys/bus/pci/devices/0000:00:06.0/virtio/host-features=0x71000ed4
   /sys/class/dmi/id/bios_vendor=Bochs
   /sys/class/dmi/id/bios_date=01/01/2007
   /sys/class/dmi/id/bios_version=Bochs
  Guest fingerprint changed for pc-1.0!
Reported-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
      ea776abc
  27. 18 8月, 2012 1 次提交
    • S
      virtio-blk: hide VIRTIO_BLK_F_CONFIG_WCE from old machine types · eec7f96c
      由 Stefan Hajnoczi 提交于 
      QEMU has a policy of keeping a stable guest device ABI.  When new guest device
features are introduced they must not change hardware info seen by existing
guests.  This is important because operating systems or applications may
"fingerprint" the hardware and refuse to run when the hardware changes.  To
always get the latest guest device ABI, run with x86 machine type "pc".

This patch hides the new VIRTIO_BLK_F_CONFIG_WCE virtio feature bit from
existing machine types.  Only pc-1.2 and later will expose this feature
by default.

For more info on the VIRTIO_BLK_F_CONFIG_WCE feature bit, see:

  commit 13e3dce0
  Author: Paolo Bonzini <pbonzini@redhat.com>
  Date:   Thu Aug 9 16:07:19 2012 +0200

      virtio-blk: support VIRTIO_BLK_F_CONFIG_WCE

      Also rename VIRTIO_BLK_F_WCACHE to VIRTIO_BLK_F_WCE for consistency with
      the spec.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Anthony Liguori <aliguori@us.ibm.com> reported:

  This broke qemu-test because it changed the pc-1.0 machine type:

  Setting guest RANDOM seed to 47167
  *** Running tests ***
  Running test /tests/finger-print.sh...		OK
  --- fingerprints/pc-1.0.x86_64	2011-12-18 13:08:40.000000000 -0600
  +++ fingerprint.txt	2012-08-12 13:30:48.000000000 -0500
  @@ -55,7 +55,7 @@
   /sys/bus/pci/devices/0000:00:06.0/subsystem_device=0x0002
   /sys/bus/pci/devices/0000:00:06.0/class=0x010000
   /sys/bus/pci/devices/0000:00:06.0/revision=0x00
  -/sys/bus/pci/devices/0000:00:06.0/virtio/host-features=0x710006d4
  +/sys/bus/pci/devices/0000:00:06.0/virtio/host-features=0x71000ed4
   /sys/class/dmi/id/bios_vendor=Bochs
   /sys/class/dmi/id/bios_date=01/01/2007
   /sys/class/dmi/id/bios_version=Bochs
  Guest fingerprint changed for pc-1.0!
Reported-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      eec7f96c
  29. 10 8月, 2012 3 次提交
  31. 17 7月, 2012 6 次提交
  33. 30 5月, 2012 2 次提交