When frontend and backend are connected through a hub as below
(showing only one direction), and the frontend (or in general, all
output ports of the hub) cannot accept more traffic, the backend
queues packets in queue-A.
When the frontend (or in general, one output port) becomes ready again,
quemu tries to flush packets from queue-B, which is unfortunately empty.
e1000.0 <--[queue B]-- hub0port0(hub)hub0port1 <--[queue A]-- tap.0
To fix this i propose to introduce a new function net_hub_flush()
which is called when trying to flush a queue connected to a hub.
Signed-off-by: Luigi Rizzo <rizzo@iet.unipi.it>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* bonzini/header-dirs: (45 commits)
janitor: move remaining public headers to include/
hw: move executable format header files to hw/
fpu: move public header file to include/fpu
softmmu: move remaining include files to include/ subdirectories
softmmu: move include files to include/sysemu/
misc: move include files to include/qemu/
qom: move include files to include/qom/
migration: move include files to include/migration/
monitor: move include files to include/monitor/
exec: move include files to include/exec/
block: move include files to include/block/
qapi: move include files to include/qobject/
janitor: add guards to headers
qapi: make struct Visitor opaque
qapi: remove qapi/qapi-types-core.h
qapi: move inclusions of qemu-common.h from headers to .c files
ui: move files to ui/ and include/ui/
qemu-ga: move qemu-ga files to qga/
net: reorganize headers
net: move net.c to net/
...
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Move public headers to include/net, and leave private headers in net/.
Put the virtio headers in include/net/tap.h, removing the multiple copies
that existed. Leave include/net/tap.h as the interface for NICs, and
net/tap_int.h as the interface for OS-specific parts of the tap backend.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Remove some redundant blanks in the comments of
net_hub_id_for_client().
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This patch doesn't seem much useful alone, I must admit. However,
it makes sense as part of the upcoming directory reorganization,
where I want to have include/net/tap.h as the net<->hw interface
for tap. Then having both net/tap.h and include/net/tap.h does
not work. "Fixed" by moving all the init functions to a single
header file net/clients.h.
The patch also adopts a uniform style for including net/*.h files
from net/*.c, without the net/ path.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>
In commit 60c07d933c ("net: fix
qemu_can_send_packet logic") the "VLAN" broadcast behavior was changed
to queue packets if any net client cannot receive. It turns out that
this was not actually the right fix and just hides the real bug that
hw/usb/dev-network.c:usbnet_receive() clobbers its receive buffer when
called multiple times in a row. The commit also introduced a new bug
that "VLAN" packets would not be sent if one of multiple net clients was
down.
The hw/usb/dev-network.c bug has since been fixed, so this patch reverts
broadcast behavior to send packets as long as one net client can
receive. Packets simply get queued for the net clients that are
temporarily unable to receive.
Reported-by: Roy.Li <rongqing.li@windriver.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Only when all other hub port's *peer* .can_receive() all return 1,
the source hub port .can_receive() return 1.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
The vlan feature is no longer part of net core. Rename VLANClientState
to NetClientState because net clients are not explicitly associated with
a vlan at all, instead they have a peer net client to which they are
connected.
This patch is a mechanical search-and-replace except for a few
whitespace fixups where changing VLANClientState to NetClientState
misaligned whitespace.
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Instead of using VLANState use net/hub.h to support the vlan qdev
property. The vlan qdev property becomes an alias for the peer qdev
property but is represented as a VLAN ID number. When a VLAN ID is
selected the device will really peer with a hub port.
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Since hubs are now used to implement the 'vlan' feature and the vlan
argument is always NULL, remove the argument entirely and update all net
clients that use qemu_new_net_client().
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Checks can be performed to make sure that hubs have at least one NIC and
one host device, warning the user if this is not the case.
Configurations which do not meet this rule tend to be broken but just
emit a warning. This patch preserves compatibility with the checks
performed by net core on vlans.
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Stop using the special-case vlan code in net.c. Instead use the hub net
client to implement the vlan feature. The next patch will remove vlan
code from net.c completely.
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
The vlan feature can be implemented in terms of hubs. By introducing a
hub net client it becomes possible to remove the special case vlan code
from net.c and push the vlan feature out of generic networking code.
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
