2.6.30 adds a new TUNSETSNDBUF ioctl() which allows a send buffer limit
for the tap device to be specified. When this limit is reached, a tap
write() will return EAGAIN and poll() will indicate the fd isn't
writable.
This allows people to tune their setups so as to avoid e.g. UDP packet
loss when the sending application in the guest out-runs the NIC in the
host.
There is no obviously sensible default setting - a suitable value
depends mostly on the capabilities of the physical NIC through which the
packets are being sent.
Also, note that when using a bridge with netfilter enabled, we currently
never get EAGAIN because netfilter causes the packet to be immediately
orphaned. Set /proc/sys/net/bridge/bridge nf-call-iptables to zero to
disable this behaviour.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
net_tap_fd_init() already returns TAPState, so this is a sensible
cleanup in its own right.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
If a write() on tapfd returns EAGAIN, return zero so that the packet
gets queued (in the case of async send) and enable polling tapfd for
writing.
When tapfd becomes writable, disable write polling and flush any queued
packets.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Add a helper to enable/disable the read polling on tapfd.
We need this, because we want to start write polling on the tapfd too
and enable/disable both types of polling independently.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
If tap has any packets queued at host_net_remove time, it needs to purge
them in order to prevent a sent callback being invoked for it.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
If net client sends packets asynchronously, it needs to purge its queued
packets in cleanup() so as to prevent sent callbacks being invoked with
a freed client.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Make net_client_init() accept addr=, put the value into struct
NICinfo. Use it in pci_nic_init(), and remove arguments bus and
devfn.
Don't support addr= in third argument of monitor command pci_add,
because that clashes with its first argument. Admittedly unelegant.
Machines "malta" and "r2d" have a default NIC with a well-known PCI
address. Deal with that the same way as the NIC model: make
pci_nic_init() take an optional default to be used when the user
doesn't specify one.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Fix the pcap dumps on Win32 and other systems where O_BINARY is required.
Signed-off-by: Filip Navara <filip.navara@gmail.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The code how it is today, is totally painful to read and keep.
To begin with, the code is duplicated with the option rom loading
code that linux_boot and vga are already using.
This patch introduces a "bootable" state in NICInfo structure,
that we can use to keep track of whether or not a given nic should
be bootable, avoiding the introduction of yet another global state.
With that in hands, we move the code in vl.c to hw/pc.c, and use
the already existing infra structure to load those option roms.
Error checking code suggested by Mark McLoughlin
Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.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>
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>
As host network devices can also be instantiated via the monitor, errors
should then be reported to the related monitor instead of stderr. This
requires larger refactoring, so this patch starts small with introducing
a helper to catch both cases and convert net_client_init as well as
net_slirp_redir.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
A small bit of confusion between buffers is causing errors like:
qemu: invalid parameter '10' in 'script=/etc/qemu-ifup,fd=10'
instead of:
qemu: invalid parameter 'script' in 'script=/etc/qemu-ifup,fd=10'
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
OK, last try: 8e4416af45 broke -net socket, ffad4116b9 tried to fix it
but broke error reporting of invalid parameters. So this patch widely
reverts ffad4116b9 again and intead fixes those callers of check_params
that originally suffered from overwritten buffers by using separate
ones.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
This reverts commit 8cf07dcbe7.
This is a sorry saga.
This commit:
8e4416af45 net: Add parameter checks for VLAN clients
broken '-net socket' and this commit:
ffad4116b9 net: Fix -net socket parameter checks
fixed the problem but introduced another problem which
this commit:
8cf07dcbe7 Fix output of uninitialized strings
fixed that final problem, but causing us to lose some
error reporting information in the process.
Meanwhile Jan posted a patch to mostly re-do ffad4116b9
in a way that fixes the original issue, but without
losing the error reporting information. So, let's revert
8cf07dcbe7 and apply Jan's patch.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Slirp uses fork_exec for spawning service processes, and QEMU uses this
for running smbd. As SIGCHLD is not handled, these processes become
zombies on termination. Fix this by installing a proper signal handler,
but also make sure we disable the signal while waiting on forked network
setup/shutdown scripts.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Fix a race in qemu_send_packet when delivering deferred packets and
add proper deferring also to qemu_sendv_packet.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
In case you're wondering what connections exactly you have open
or maybe redir'ed in the past, you can't really find out from qemu
right now.
This patch enables you to see all current connections the host
only networking holds open, so you can kill them using the previous
patch.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Using the new host_net_redir command you can easily create redirections
on the fly while your VM is running.
While that's great, it's missing the removal of redirections, in case you
want to have a port closed again at a later point in time.
This patch adds support for removal of redirections.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Commit ffad4116b9 removed the "scratch buffer"
from check_params, but didn't care for the error messages which actually
included this string to tell the user which option was wrong. Now this string
is uninitialized, so this patch removes it from the message.
This means that the user is only told the whole parameter string and has to
pick the wrong option by himself as the callers of check_params can't know this
value any more. An alternative approach would be to revert that commit and do
whatever is needed to fix the original problem without changing check_params.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
My commit ea053add70 broke -net socket by
overwriting an intermediate buffer in the added check_param. Fix this
by switching check_param to automatic buffer allocation and release, ie.
callers no longer have to worry about providing a scratch buffer.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
>> + if (net_client_init(device, opts ? : "") < 0) {
>
> Is this a gcc extension? Do we want to introduce this construct to the
> code base.
Valid remark, fix below.
Thanks,
Jan
-------->
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Fix net.c compile warning:
CC net.o
net.c: In function ‘net_slirp_redir’:
net.c:623: warning: format not a string literal and no format arguments
Signed-off-by: Robert Reif <reif@earthlink.net>
The slirp stack is full of global variables which prevents instantiating
it more than once. Catch this during net_slirp_init to prevent more harm
later on.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7208 c046a42c-6fe2-441c-8c8c-71466251a162
Allow to establish a TCP/UDP connection redirection also via a monitor
command 'host_net_redir'. Moreover, assume TCP as connection type if
that parameter is omitted.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7204 c046a42c-6fe2-441c-8c8c-71466251a162
Queue packets that are send during an ongoing packet delivery. This
ensures that packets will always arrive in their logical order at each
client of a VLAN. Currently, slirp generates such immediate relies, and
e.g. packet-sniffing clients on the same VLAN may get confused.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7203 c046a42c-6fe2-441c-8c8c-71466251a162
Fix the documentation of the host_net_add monitor command and allow the
user to pass no options at all. Moreover, inform the user on the
monitor terminal if a request failed.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7201 c046a42c-6fe2-441c-8c8c-71466251a162
This patch is derived from Tristan Gingold's patch. It adds a new VLAN
client type that writes all traffic on the VLAN it is attached to into a
pcap file. Such a file can then be analyzed offline with Wireshark or
tcpdump.
Besides rebasing and some minor cleanups, the major differences to the
original version are:
- support for enabling/disabling via the monitor (host_net_add/remove)
- no special ordering of VLAN client list, qemu_send_packet now takes
care of properly ordered packets
- 64k default capturing limit (I hate tcpdump's default)
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7200 c046a42c-6fe2-441c-8c8c-71466251a162
This aims at helping the user to find typos or other mistakes in
parameter lists passed for VLAN client initialization. The existing
parsing infrastructure does not allow a leaner approach, but this is
better than nothing IMHO.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7197 c046a42c-6fe2-441c-8c8c-71466251a162
In case no symbolic name is provided when requesting VLAN connection via
listening TCP socket ('-net socket,listen=...'), qemu crashes. This
fixes the cause.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7196 c046a42c-6fe2-441c-8c8c-71466251a162
Make sure that we do not delete guest NICs via host_net_remove.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7195 c046a42c-6fe2-441c-8c8c-71466251a162
It's allocated using qemu_mallocz(), so ...
The name and model strings are strdup() allocated, so free()
is still appropriate for them.
Reported-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7151 c046a42c-6fe2-441c-8c8c-71466251a162
We're currently leaking memory and file descriptors on device
hot-unplug.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7150 c046a42c-6fe2-441c-8c8c-71466251a162
Mark McLoughlin
Markus Armbruster
Filip Navara
Glauber Costa
Stefan Weil
Blue Swirl
Anthony Liguori
Jan Kiszka
Alexander Graf
Kevin Wolf
Jan Kiszka
Paul Brook
Robert Reif
aliguori