Needed for savevm/loadvm + migration: In that case the queue might
already have packets on (re-)connect. The guest wouldn't notify us
because notifications are only sent when stuffing a packet into an
empty queue.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Type casts removing the const attribute are bad because
they hide the fact that the argument remains const.
They also result in a compiler warning (at least with MS-C).
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Work around buffer and ioctlsocket argument type signedness problems
Suppress a prototype which is unused on mingw32
Expand a macro to avoid warnings from some GCC versions
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Additional hosts can be added to the white list as they are confirmed to build
with --enable-werror.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Rationale: move device information from code to data structures.
v2: Adapt the drivers missed in the first version.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
* net-queue: (28 commits)
virtio-net: Increase filter and control limits
virtio-net: Add new RX filter controls
virtio-net: MAC filter optimization
virtio-net: Fix MAC filter overflow handling
virtio-net: reorganize receive_filter()
virtio-net: Use a byte to store RX mode flags
virtio-net: Add version_id 7 placeholder for vnet header support
virtio-net: implement rx packet queueing
net: make use of async packet sending API in tap client
net: add qemu_send_packet_async()
net: split out packet queueing and flushing into separate functions
net: return status from qemu_deliver_packet()
net: add return value to packet receive handler
net: pass VLANClientState* as first arg to receive handlers
net: re-name vc->fd_read() to vc->receive()
net: add fd_readv() handler to qemu_new_vlan_client() args
net: only read from tapfd when we can send
net: vlan clients with no fd_can_read() can always receive
net: move the tap buffer into TAPState
net: factor tap_read_packet() out of tap_send()
...
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The function qemu_calculate_timeout() is only used when CONFIG_IOTHREAD
is not defined. When CONFIG_IOTHREAD is defined, we have the following
warning:
vl.c:4389: warning: ‘qemu_calculate_timeout’ defined but not used
This change fixes that by moving the #ifdef/#endif from main_loop()
into qemu_calculate_timeout(). This encapsulates the logic and allow
us to use qemu_calculate_timeout() when CONFIG_IOTHREAD is defined
or not (suggested by Glauber Costa).
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Move code to extract command name into a function of its own, this
clearifies the code and let us remove two variables from
monitor_handle_command().
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
The 'found' goto in monitor_handle_command() can be dropped if we check
for 'cmd->name' after looking up for the command to execute.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Increase the size of the perfect filter table and control queue depth.
This should give us more headroom in the MAC filter and is known to be
needed by at least one guest user. Increasing the control queue depth
allows a guest to feed several commands back to back if they so desire
rather than using the send and wait approach Linux uses.
Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Add a few new RX modes to better control the receive_filter. These
are all fairly obvious features that hardware could provide.
Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
The MAC filter table is received from the guest as two separate
buffers, one with unicast entries, the other with multicast
entries. If we track the index dividing the two sets, we can
avoid searching the part of the table with the wrong type of
entries.
We could store this index as part of the save image, but its
trivially easy to discover it on load.
Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Overloading the promisc and allmulti flags for indicating filter
table overflow makes it difficult to track the actual requested
operating mode. Split these out into separate flags.
Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Reorganize receive_filter to better handle the split between
unicast and multicast filtering. This allows us to skip the
broadcast check on unicast packets and leads to more opportunities
for optimization.
Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
There's no need to save 4 bytes for promisc and allmulti.
Use one byte each just to avoid the overhead of a bitmap.
Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
If we don't have room to receive a packet, we return zero
from virtio_net_receive() and call qemu_flush_queued_packets()
as soon as space becomes available.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
If a packet is queued by qemu_send_packet(), remove I/O
handler for the tap fd until we get notification that the
packet has been sent.
A not insignificant side effect of this is we can now
drain the tap send queue in one go without fear of packets
being dropped.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Add a qemu_send_packet() variant which will queue up the packet
if it cannot be sent when all client queues are full. It later
invokes the supplied callback when the packet has been sent.
If qemu_send_packet_async() returns zero, the caller is expected
to not send any more packets until the queued packet has been
sent.
Packets are queued iff a receive() handler returns zero (indicating
queue full) and the caller has provided a sent notification callback
(indicating it will stop and start its own queue).
We need the packet sending API to support queueing because:
- a sending client should process all available packets in one go
(e.g. virtio-net emptying its tx ring)
- a receiving client may not be able to handle the packet
(e.g. -EAGAIN from write() to tapfd)
- the sending client could detect this condition in advance
(e.g. by select() for writable on tapfd)
- that's too much overhead (e.g. a select() call per packet)
- therefore the sending client must handle the condition by
dropping the packet or queueing it
- dropping packets is poor form; we should queue.
However, we don't want queueing to be completely transparent. We
want the sending client to stop sending packets as soon as a
packet is queued. This allows the sending client to be throttled
by the receiver.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
VLANClientState's fd_read() handler doesn't read from file
descriptors, it adds a buffer to the client's receive queue.
Re-name the handlers to make things a little less confusing.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
This, apparently, is the style we prefer - all VLANClientState
should be an argument to qemu_new_vlan_client().
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Reduce the number of packets dropped under heavy network
traffic by only reading a packet from the tapfd when a
client can actually handle it.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
If a vlan client has no fd_can_read(), that means it can
always receive packets. The current code assumes it can *never*
receive packets.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
KVM uses a 64k buffer for reading from tapfd (for GSO support)
and allocates the buffer with TAPState rather than on the stack.
Not allocating it on the stack probably makes sense for qemu
anyway, so merge it in advance of GSO support.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
This patch reorders the initialization of slirp itself as well as its
associated features smb and redirection. So far the first reference to
slirp triggered the initialization, independent of the actual -net user
option which may carry additional parameters. Now we save any request to
add a smb export or some redirections until the actual initialization of
the stack. This also allows to move a few parameters that were passed
via global variable into the argument list of net_slirp_init.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>