Commit Graph

22 Commits

Author SHA1 Message Date
Anthony Liguori 7b2f89c435 Merge remote-tracking branch 'kwolf/for-anthony' into staging
* kwolf/for-anthony:
  virtio-blk: hide VIRTIO_BLK_F_CONFIG_WCE from old machine types
  Documentation: Warn against qemu-img on active image
  vmdk: Read footer for streamOptimized images
  vmdk: Fix header structure

Conflicts:
	hw/virtio-blk.c
2012-08-22 13:01:05 -05:00
Stefan Hajnoczi ea776abca6 virtio-blk: hide VIRTIO_BLK_F_CONFIG_WCE from old machine types
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 13e3dce068
  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: Paolo Bonzini <pbonzini@redhat.com>
      Signed-off-by: Kevin 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: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-08-22 10:47:14 -05:00
Stefan Hajnoczi eec7f96c2c virtio-blk: hide VIRTIO_BLK_F_CONFIG_WCE from old machine types
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 13e3dce068
  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: Paolo Bonzini <pbonzini@redhat.com>
      Signed-off-by: Kevin 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: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-08-17 21:29:24 +02:00
Paolo Bonzini 13e3dce068 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: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-08-10 10:25:12 +02:00
Markus Armbruster 31e404f4ff hw/block-common: Move BlockConf & friends from block.h
This stuff doesn't belong to block layer, and was put there only
because a better home didn't exist then.  Now it does.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-07-17 16:48:32 +02:00
Paolo Bonzini a6c5c84ae2 virtio-blk: always enable VIRTIO_BLK_F_SCSI
VIRTIO_BLK_F_SCSI is supposed to mean whether the host can *parse*
SCSI requests, not *execute* them.  You could run QEMU with scsi=on
and a file-backed disk, and QEMU would fail all SCSI requests even
though it advertises VIRTIO_BLK_F_SCSI.

Because we need to do this to fix a migration compatibility problem
related to how QEMU is invoked by management, we must do this
unconditionally even on older machine types.  This more or less assumes
that no one ever invoked QEMU with scsi=off.

Here is how testing goes:

- old QEMU, scsi=on -> new QEMU, scsi=on
- new QEMU, scsi=on -> old QEMU, scsi=on
- old QEMU, scsi=off -> new QEMU, scsi=on
- new QEMU, scsi=off -> old QEMU, scsi=on
        ok (new QEMU has VIRTIO_BLK_F_SCSI, adding host features is fine)

- old QEMU, scsi=off -> new QEMU, scsi=off
        ok (new QEMU has VIRTIO_BLK_F_SCSI, adding host features is fine)

- old QEMU, scsi=on -> new QEMU, scsi=off
        ok, bug fixed

- new QEMU, scsi=on -> old QEMU, scsi=off
        doesn't work (same as: old QEMU, scsi=on -> old QEMU, scsi=off)

- new QEMU, scsi=off -> old QEMU, scsi=off
        broken by the patch

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-05-21 15:40:50 -05:00
Paolo Bonzini 12c5674b84 virtio-blk: define VirtIOBlkConf
We will have to add another field to the virtio-blk configuration in
the next patch.  Avoid a proliferation of arguments to virtio_blk_init.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-05-21 15:40:50 -05:00
Stefan Weil 541dc0d47f Use new macro QEMU_PACKED for packed structures
Most changes were made using these commands:

git grep -la '__attribute__((packed))'|xargs perl -pi -e 's/__attribute__\(\(packed\)\)/QEMU_PACKED/'
git grep -la '__attribute__ ((packed))'|xargs perl -pi -e 's/__attribute__ \(\(packed\)\)/QEMU_PACKED/'
git grep -la '__attribute__((__packed__))'|xargs perl -pi -e 's/__attribute__\(\(__packed__\)\)/QEMU_PACKED/'
git grep -la '__attribute__ ((__packed__))'|xargs perl -pi -e 's/__attribute__ \(\(__packed__\)\)/QEMU_PACKED/'
git grep -la '__attribute((packed))'|xargs perl -pi -e 's/__attribute\(\(packed\)\)/QEMU_PACKED/'

Whitespace in linux-user/syscall_defs.h was fixed manually
to avoid warnings from scripts/checkpatch.pl.

Manual changes were also applied to hw/pc.c.

I did not fix indentation with tabs in block/vvfat.c.
The patch will show 4 errors with scripts/checkpatch.pl.

Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-09-03 10:45:59 +00:00
Markus Armbruster a8686a9b2b virtio-blk: Turn drive serial into a qdev property
It needs to be a qdev property, because it belongs to the drive's
guest part.  Precedence: commit a0fef654 and 6ced55a5.

Bonus: info qtree now shows the serial number.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-05 11:23:29 +02:00
john cooper 2930b313dd Add virtio disk identification support
This patch adds the final missing bits for support of
passing a serial/id string to a virtio-blk guest driver.

The guest-side component already exists in the virtio
driver, and has recently been reworked by Ryan to export
a /sys interface for retrieval of the id from guest userland.

Signed-off-by: john cooper <john.cooper@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-07-06 17:05:49 +02:00
Christoph Hellwig 8cfacf0790 block: add logical_block_size property
Add a logical block size attribute as various guest side tools only
increase the filesystem sector size based on it, not the advisory
physical block size.

For scsi we already have support for a different logical block size
in place for CDROMs that we can built upon.  Only my recent block
device characteristics VPD page needs some fixups.  Note that we
leave the logial block size for CDROMs hardcoded as the 2k value
is expected for it in general.

For virtio-blk we already have a feature flag claiming to support
a variable logical block size that was added for the s390 kuli
hypervisor.  Interestingly it does not actually change the units
in which the protocol works, which is still fixed at 512 bytes,
but only communicates a different minimum I/O granularity.  So
all we need to do in virtio is to add a trap for unaligned I/O
and round down the device size to the next multiple of the logical
block size.

IDE does not support any other logical block size than 512 bytes.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-03-17 10:42:27 -05:00
Christoph Hellwig 9752c371a2 virtio-blk: add topology support
Export all topology information in the block config structure,
guarded by a new VIRTIO_BLK_F_TOPOLOGY feature flag.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-02-10 16:53:54 -06:00
hch@lst.de 37d5ddd6f4 virtio-blk: revert serial number support
The addition of the whole ATA IDENTIY page caused the config space to
go above the allowed size in the PCI spec, and thus the feature was
already reverted in the Linux guest driver and disabled by default in
qemu.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-02-10 16:51:31 -06:00
Michael S. Tsirkin 8172539d21 virtio: add features as qdev properties
Add feature bits as properties to virtio. This makes it possible to e.g. define
machine without indirect buffer support, which is required for 0.10
compatibility, or without hardware checksum support, which is required for 0.11
compatibility.  Since default values for optional features are now set by qdev,
get_features callback has been modified: it sets non-optional bits, and clears
bits not supported by host.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-11 13:40:59 -06:00
Christoph Hellwig aa659be3dc virtio-blk: add volatile writecache feature
Add a new VIRTIO_BLK_F_WCACHE feature to virtio-blk to indicate that we have
a volatile write cache that needs controlled flushing.  Implement a
VIRTIO_BLK_T_FLUSH operation to flush it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-09-11 10:19:46 -05:00
john cooper bf011293fa Add serial number support for virtio_blk
[brought forward to current qemu-kvm.git]

This patch implements the missing qemu logic to
interpret a '-drive .. serial=XYZ ..' flag for
a virtio_blk device.

The serial number string is contained in a
skeletal IDENTIFY DEVICE data structure and
this structure is made available to the guest
virtio_blk driver via pci i/o region 0.

Signed-off-by: john cooper <john.cooper@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-06-24 09:09:15 -05:00
Paul Brook 53c25cea7d Separate virtio PCI code
Split the PCI host bindings from the VRing transport implementation.

Signed-off-by: Paul Brook <paul@codesourcery.com>
2009-05-18 18:26:33 +01:00
Paul Brook 07e3af9ac3 Virtio-blk qdev conversion
Signed-off-by: Paul Brook <paul@codesourcery.com>
2009-05-14 22:35:08 +01:00
Christoph Hellwig 8b91408b62 fix virtio_blk_inhdr comment
The inhdr is at the end of the S/G list, not the beginning.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-05-01 09:44:11 -05:00
Christoph Hellwig 1063b8b15f virtio-blk: add SGI_IO passthru support
[had the qemu list address wrong the first time, reply to this message,
 not the previous if you were on Cc]

Add support for SG_IO passthru (packet commands) to the virtio-blk
backend.  Conceptually based on an older patch from Hannes Reinecke
but largely rewritten to match the code structure and layering in
virtio-blk.

Note that currently we issue the hose SG_IO synchronously.  We could
easily switch to async I/O, but that would required either bloating
the VirtIOBlockReq by the size of struct sg_io_hdr or an additional
memory allocation for each SG_IO request.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-05-01 09:44:10 -05:00
aliguori 9b32d5a5f7 pci: virtio: use pci id defines (Gerd Hoffman)
Use the defines added by the previous patch in the virtio drivers.
Also remove the pointless vendor and device args from the
virtio_blk_init() function.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5987 c046a42c-6fe2-441c-8c8c-71466251a162
2008-12-11 21:20:03 +00:00
aliguori 6e02c38dad Add virtio-blk support
Virtio-blk is a paravirtual block device based on VirtIO.  It can be used by
specifying the if=virtio parameter to the -drive parameter.

When using -enable-kvm, it can achieve very good performance compared to IDE or
SCSI.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5870 c046a42c-6fe2-441c-8c8c-71466251a162
2008-12-04 19:52:44 +00:00