Skip to content

Q
qemu

openeuler / qemu

通知 10
Star 0
Fork 0
Q
qemu

体验新版 GitCode，发现更多精彩内容 >>

切换分支/标签
  1. 23 7月, 2012 5 次提交
  3. 15 6月, 2012 1 次提交
  5. 05 6月, 2012 1 次提交
  7. 02 2月, 2012 1 次提交
    • C
      Add support for net bridge · a7c36ee4
      由 Corey Bryant 提交于 
      The most common use of -net tap is to connect a tap device to a bridge.  This
requires the use of a script and running qemu as root in order to allocate a
tap device to pass to the script.

This model is great for portability and flexibility but it's incredibly
difficult to eliminate the need to run qemu as root.  The only really viable
mechanism is to use tunctl to create a tap device, attach it to a bridge as
root, and then hand that tap device to qemu.  The problem with this mechanism
is that it requires administrator intervention whenever a user wants to create
a guest.

By essentially writing a helper that implements the most common qemu-ifup
script that can be safely given cap_net_admin, we can dramatically simplify
things for non-privileged users.  We still support existing -net tap options
as a mechanism for advanced users and backwards compatibility.

Currently, this is very Linux centric but there's really no reason why it
couldn't be extended for other Unixes.

A typical invocation would be similar to one of the following:

  qemu linux.img -net bridge -net nic,model=virtio

  qemu linux.img -net tap,helper="/usr/local/libexec/qemu-bridge-helper"
                 -net nic,model=virtio

  qemu linux.img -netdev bridge,id=hn0
                 -device virtio-net-pci,netdev=hn0,id=nic1

  qemu linux.img -netdev tap,helper="/usr/local/libexec/qemu-bridge-helper",id=hn0
                 -device virtio-net-pci,netdev=hn0,id=nic1

The default bridge that we attach to is br0.  The thinking is that a distro
could preconfigure such an interface to allow out-of-the-box bridged networking.

Alternatively, if a user wants to use a different bridge, a typical invocation
would be simliar to one of the following:

  qemu linux.img -net bridge,br=qemubr0 -net nic,model=virtio

  qemu linux.img -net tap,helper="/usr/local/libexec/qemu-bridge-helper --br=qemubr0"
                 -net nic,model=virtio

  qemu linux.img -netdev bridge,br=qemubr0,id=hn0
                 -device virtio-net-pci,netdev=hn0,id=nic1

  qemu linux.img -netdev tap,helper="/usr/local/libexec/qemu-bridge-helper --br=qemubr0",id=hn0
                 -device virtio-net-pci,netdev=hn0,id=nic1
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NRicha Marwaha <rmarwah@linux.vnet.ibm.com>
Signed-off-by: NCorey Bryant <coreyb@linux.vnet.ibm.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
      a7c36ee4
  9. 16 12月, 2011 1 次提交
  11. 08 6月, 2011 1 次提交
  13. 02 2月, 2011 1 次提交
  15. 16 11月, 2010 2 次提交
  17. 14 11月, 2010 1 次提交
  19. 04 11月, 2010 1 次提交
  21. 08 9月, 2010 2 次提交
  23. 26 4月, 2010 1 次提交
  25. 02 4月, 2010 3 次提交
  27. 22 3月, 2010 1 次提交
  29. 20 3月, 2010 1 次提交
  31. 16 3月, 2010 2 次提交
  33. 20 2月, 2010 1 次提交
  35. 08 1月, 2010 1 次提交
  37. 03 12月, 2009 3 次提交
  39. 21 11月, 2009 1 次提交
  41. 09 11月, 2009 2 次提交
    • M
      tap: drain queue in tap_send() · 5819c918
      由 Mark McLoughlin 提交于 
      Okay, let's try re-enabling the drain-entire-queue behaviour, with a
difference - before each subsequent packet, use qemu_can_send_packet()
to check that we can send it. This is similar to how we check before
polling the tap fd and avoids having to drop a packet if the receiver
cannot handle it.

This patch should be a performance improvement since we no longer have
to go through the mainloop for each packet.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
      5819c918
    • M
      tap: disable draining queue in one go · be1636b3
      由 Mark McLoughlin 提交于 
      If qemu_send_packet_async() returns zero, it means the packet has been
queued and the sent callback will be invoked once it has been flushed.

This is only possible where the NIC's receive() handler returns zero
and promises to notify the networking core that room is available in its
queue again.

In the case where the receive handler does not have this capability
(and its queue fills up) it returns -1 and the networking core does not
queue up the packet. This condition is indicated by a -1 return from
qemu_send_packet_async().

Currently, tap handles this condition simply by dropping the packet. It
should do its best to avoid getting into this situation by checking such
NIC's have room for a packet before copying the packet from the tap
interface.

tap_send() used to achieve this by only reading a single packet before
returning to the mainloop. That way, tap_can_send() is called before
reading each packet.

tap_send() was changed to completely drain the tap interface queue
without taking into account the situation where the NIC returns an
error and the packet is not queued. Let's start fixing this by
reverting to the previous behaviour of reading one packet at a time.
Reported-by: NScott Tsai <scottt.tw@gmail.com>
Tested-by: NSven Rudolph <Sven_Rudolph@drewag.de>
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
      be1636b3
  43. 31 10月, 2009 1 次提交
    • A
      Unbreak tap compilation on OS X · 71f4effc
      由 Alexander Graf 提交于 
      Currently compiling the tap sources breaks on Mac OS X. This is because of:

  1) tap-linux.h requiring Linux includes
  2) typos
  3) missing #includes

This patch adds what's necessary to compile tap happily on Mac OS X.
I haven't tested if using tap actually works, but I don't think that's a
major issue as that code was probably seriously untested before already.

I didn't split the patch, because it's only a few lines of code and
splitting is probably not worth the effort here.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
      71f4effc
  45. 30 10月, 2009 6 次提交