Allocate the internal slirp state dynamically and provide and call
slirp_cleanup to properly release it after use. This patch finally
unbreaks slirp release and re-instantiation via host_net_* monitor
commands.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This now also exports the internal state to the slirp users in qemu,
returning it from slirp_init and expecting it along with service
invocations. Additionally provide an opaque value interface for the
callbacks from slirp into the qemu core.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Slirp doesn't invoke slirp[_can]_output before it is initialized. The
motivation for these checks (3b7f5d47) no longer applies. So drop
them.

Note: slirp_vc will become invalid if the slirp stack is removed during
runtime. But this is no new bug and will be fixed later.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Avoid the need for slirp_is_inited by refactoring the protected
slirp_select_* functions. This also avoids the clearing of all fd sets
on select errors.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

As agreed on the mailing list, there is no interest in keeping the
usually disabled slirp statistics in the tree. So this patch removes
them.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Break out sockstats from the slirp statistics and present them under the
new info category "usernet". This patch also improves the current output
/wrt proper reporting connection source and destination.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Prevent that the users accidentally shoots down dynamic sockets. This
allows to remove looping for removals as there can now only be one
match.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Extend the hostfwd rule format so that the user can specify on which
host interface qemu should listen for incoming connections. If omitted,
binding will takes place against all interfaces.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Improve the monitor interface for adding and removing host forwarding
rules by splitting it up in two commands and rename them to hostfwd_add
and hostfwd_remove. Also split up the paths taken for legacy -redir
support and the monitor add command as the latter will be extended later
on.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

With the internal IP configuration made more flexible, we can now
enhance the user interface. This patch adds a number of new options to
"-net user": net (address and mask), host, dhcpstart, dns and smbserver.
It also renames "redir" to "hostfwd" and "channel" to "guestfwd" in
order to (hopefully) clarify their meanings. The format of guestfwd is
extended so that the user can define not only the port but also the
virtual server's IP address the forwarding starts from.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

So far a couple of slirp-related parameters were expressed via
stand-alone command line options. This it inconsistent and unintuitive.
Moreover, it prevents both dynamically reconfigured (host_net_add/
delete) and multi-instance slirp.

This patch refactors the configuration by turning -smb, -redir, -tftp
and -bootp as well as -net channel into options of "-net user". The old
stand-alone command line options are still processed, but no longer
advertised. This allows smooth migration of management applications to
to the new syntax and also the extension of that syntax later in this
series.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This reverts commit 1c6ed9f3.

It's redundant to slirp statistics, which are going to be split up /
reworked later on.

Conflicts:

	monitor.c
	net.c
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Add an option to specify the number of MSI-X vectors for PCI NIC cards. This
can also be used to disable MSI-X, for compatibility with old qemu. This
option currently only affects virtio cards.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

virtio-net needs this - for the same purpose that it currently uses the
return value from qemu_sendv_packet().
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

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: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony 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: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony 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: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony 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: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony 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: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony 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: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony 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: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Fix the pcap dumps on Win32 and other systems where O_BINARY is required.
Signed-off-by: NFilip Navara <filip.navara@gmail.com>
Signed-off-by: NAnthony 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: NGlauber Costa <glommer@redhat.com>
Signed-off-by: NAnthony 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: NStefan 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: NBlue Swirl <blauwirbel@gmail.com>

Signed-off-by: NAnthony Liguori <aliguori@us.ibm.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: NMark 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: NMark McLoughlin <markmc@redhat.com>

We'll be doing more packet queueing in later commits.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>

Will allow qemu_send_packet() handle queue full condition.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>

This allows us to handle queue full conditions rather than dropping
the packet on the floor.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>

Give static type checking a chance to catch errors.
Signed-off-by: NMark 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: NMark 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: NMark 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: NMark 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: NMark 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: NMark McLoughlin <markmc@redhat.com>

Move portability clutter out into its own function.
Signed-off-by: NMark 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: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NMark 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: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NMark McLoughlin <markmc@redhat.com>