configure: check that C++ compiler actually works

Check that the C++ compiler works with the C compiler; if it
does not, then don't pass CXX to the build process. This
fixes a regression where QEMU was no longer building if the
build environment didn't have a C++ compiler (introduced
in commit 3144f78b, which incorrectly assumed that rules.mak
would only see a non-empty $(CXX) if configure had actually
found a working C++ compiler).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reported-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Tested-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-id: 1392909016-14028-1-git-send-email-peter.maydell@linaro.org
Merge remote-tracking branch 'remotes/bonzini/configure' into staging

* remotes/bonzini/configure:
  build: softmmu targets do not have a "main.o" file
  configure: Disable libtool if -fPIE does not work with it (bug #1257099)
  block: convert block drivers linked with libs to modules
  Makefile: introduce common-obj-m and block-obj-m for DSO
  Makefile: install modules with "make install"
  module: implement module loading
  rules.mak: introduce DSO rules
  darwin: do not use -mdynamic-no-pic
  block: use per-object cflags and libs
  rules.mak: allow per object cflags and libs
  rules.mak: fix $(obj) to a real relative path
  util: Split out exec_dir from os_find_datadir

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Merge remote-tracking branch 'remotes/sstabellini/xen-140220' into staging

* remotes/sstabellini/xen-140220:
  xen_disk: fix io accounting
  Call pci_piix3_xen_ide_unplug from unplug_disks

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block patches

# gpg: Signature made Fri 21 Feb 2014 21:42:24 GMT using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"

* remotes/kevin/tags/for-upstream: (54 commits)
  iotests: Mixed quorum child device specifications
  quorum: Simplify quorum_open()
  quorum: Add unit test.
  quorum: Add quorum_open() and quorum_close().
  quorum: Implement recursive .bdrv_recurse_is_first_non_filter in quorum.
  quorum: Add quorum_co_flush().
  quorum: Add quorum_invalidate_cache().
  quorum: Add quorum_getlength().
  quorum: Add quorum mechanism.
  quorum: Add quorum_aio_readv.
  blkverify: Extract qemu_iovec_clone() and qemu_iovec_compare() from blkverify.
  quorum: Add quorum_aio_writev and its dependencies.
  quorum: Create BDRVQuorumState and BlkDriver and do init.
  quorum: Create quorum.c, add QuorumChildRequest and QuorumAIOCB.
  check-qdict: Test termination of qdict_array_split()
  check-qdict: Adjust test for qdict_array_split()
  qdict: Extract non-QDicts in qdict_array_split()
  qemu-config: Sections must consist of keys
  qemu-iotests: Check qemu-img command line parsing
  qemu-img: Allow -o help with incomplete argument list
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
opencores_eth: flush queue whenever can_receive can go from false to true

The following registers control whether MAC can receive frames:
- MODER.RXEN bit that enables/disables receiver;
- TX_BD_NUM register that specifies number of RX descriptors.
Notify QEMU networking core when the MAC is ready to receive frames.
Discard frame and raise BUSY interrupt when the frame arrives but the
current RX descriptor is not empty.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
net: change vnet-hdr TAP prototypes

The tap_has_vnet_hdr() and tap_has_vnet_hdr_len() functions used
to return int, even though they only return true/false values.
This patch changes the prototypes to return bool.

Signed-off-by: Vincenzo Maffione <v.maffione@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
net: extend NetClientInfo for offloading

Some new callbacks have been added to generalize the operations done
by virtio-net and vmxnet3 frontends to manipulate TAP offloadings.

Signed-off-by: Vincenzo Maffione <v.maffione@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
net: TAP uses NetClientInfo offloading callbacks

The TAP NetClientInfo structure is inizialized with the TAP-specific
functions that manipulates offloading features.

Signed-off-by: Vincenzo Maffione <v.maffione@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
net: virtio-net and vmxnet3 use offloading API

With this patch, virtio-net and vmxnet3 frontends make
use of the qemu_peer_* API for backend offloadings manipulations,
instead of calling TAP-specific functions directly.
We also remove the existing checks which prevent those frontends
from using offloadings with backends different from TAP (e.g. netmap).

Signed-off-by: Vincenzo Maffione <v.maffione@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
net: make tap offloading callbacks static

Since TAP offloadings are manipulated through a new API, it's
not necessary to export them in include/net/tap.h anymore.

Signed-off-by: Vincenzo Maffione <v.maffione@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
net: add offloading support to netmap backend

Whit this patch, the netmap backend supports TSO/UFO/CSUM
offloadings, and accepts the virtio-net header, similarly to what
happens with TAP. The offloading callbacks in the NetClientInfo
interface have been implemented.

Signed-off-by: Vincenzo Maffione <v.maffione@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
net: Disable netmap backend when not supported

This patch fixes configure so that the netmap backend is not compiled in if the
host doesn't support an API version >= 11. A version upper bound (15) has been
added so that the netmap API can be extended with some minor features without
requiring QEMU code modifications.

Moreover, some changes have been done to net/netmap.c in order to reflect the
current netmap API/ABI (11).

The NETMAP_WITH_LIBS macro makes possible to include some utilities (e.g.
netmap ring macros, D(), RD() and other high level functions) through the netmap
headers. In this way we get rid of the D and RD macro definitions in the QEMU
code, and we open the way for further code simplifications that will be
introduced by future patches.

Signed-off-by: Vincenzo Maffione <v.maffione@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Merge remote-tracking branch 'remotes/xtensa/tags/20140224-xtensa' into staging

Xtensa fixes and improvements queue 2014-02-24:
- add support for ML605 and KC705 FPGA boards;
- flush opencores_eth queue when new RX descriptor is available;
- add basic checks to cache opcodes;
- make core configuration available to tests;
- implement HW config ID special registers.

# gpg: Signature made Mon 24 Feb 2014 00:52:42 GMT using RSA key ID F83FA044
# gpg: Good signature from "Max Filippov <max.filippov@cogentembedded.com>"
# gpg:                 aka "Max Filippov <jcmvbkbc@gmail.com>"

* remotes/xtensa/tags/20140224-xtensa:
  target-xtensa: provide HW confg ID registers
  target-xtensa: refactor standard core configuration
  target-xtensa: add basic tests for cache opcodes
  target-xtensa: allow using core configuration in tests
  target-xtensa: add overridable test_init macro
  target-xtensa: add basic checks to icache opcodes
  target-xtensa: add basic checks to dcache opcodes
  target-xtensa: add RRRI4 opcode format fields
  opencores_eth: flush queue whenever can_receive can go from false to true
  hw/xtensa: add support for ML605 and KC705 FPGA board

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Merge remote-tracking branch 'remotes/mdroth/qga-pull-2014-02-24' into staging

* remotes/mdroth/qga-pull-2014-02-24:
  qemu-ga: isa-serial support on Windows
  qga: Fix memory allocation pasto
  qga: Don't require 'time' argument in guest-set-time command
  qga: vss-win32: Fix interference with snapshot deletion by other VSS request
  qga: vss-win32: Fix interference with snapshot creation by other VSS requesters
  qga: vss-win32: Use NULL as an invalid pointer for OpenEvent and CreateEvent

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
qemu_file: use fwrite() correctly

fwrite() returns the number of items written.  But when there is one
error, it can return a short write.

In the particular bug that I was tracking, I did a migration to a
read-only filesystem.  And it was able to finish the migration
correctly.  fwrite() never returned a negative error code, nor zero,
always 4096. (migration writes chunks of about 14000 bytes).  And it
was able to "complete" the migration with success (yes, reading the
file was a bit more difficult).

To add insult to injury, if your amount of memory was big enough (12GB
on my case), it overwrote some important structure, and from them,
malloc failed.  This check makes the problem go away.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Fix vmstate_info_int32_le comparison/assign

Fix comparison of vmstate_info_int32_le so that it succeeds if loaded
value is (l)ess than or (e)qual

When the comparison succeeds, assign the value loaded
  This is a change in behaviour but I think the original intent, since
  the idea is to check if the version/size of the thing you're loading is
  less than some limit, but you might well want to do something based on
  the actual version/size in the file

Fix up comment and name text

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Fix two XBZRLE corruption issues

Push zero'd pages into the XBZRLE cache
    A page that was cached by XBZRLE, zero'd and then XBZRLE'd again
    was being compared against a stale cache value

Don't use 'qemu_put_buffer_async' to put pages from the XBZRLE cache
    Since the cache might change before the data hits the wire

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
rdma: rename 'x-rdma' => 'rdma'

As far as we can tell, all known bugs have been fixed:

1. Parallel migrations are working
2. IPv6 migration is working
3. virt-test is working

I'm not comfortable sending the revised libvirt patch
until this is accepted or review suggestions are addressed,
(including pin-all support. It does not make sense to
remove experimental for one thing and not the other. That's
too many trips through the libvirt community).

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael R. Hines <mrhines@us.ibm.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
net: remove implicit peer from offload API

The virtio_net offload APIs are used on the NIC's peer (i.e. the tap
device).  The API was defined to implicitly use nc->peer, saving the
caller the trouble.

This wasn't ideal because:
1. There are callers who have the peer but not the NIC.  Currently they
   are forced to bypass the API and access peer->info->... directly.
2. The rest of the net.h API uses nc, not nc->peer, so it is
   inconsistent.

This patch pushes nc->peer back up to callers.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
vhost_net: use offload API instead of bypassing it

There is no need to access backend->info->has_vnet_hdr() and friends
anymore.  Use the qemu_has_vnet_hdr() API instead.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>