This patch implements support for Multiboot on x86 for -kernel.
Multiboot is a "new" approach to get rid of different bootloaders, providing
a unified interface for the kernel. It supports command line options and
kernel modules.

The two probably best known projects using multiboot are Xen and GNU Hurd.

This implementation should be mostly feature-complete. It is missing VBE
extensions, but as no system uses them currently it does not really hurt.

To use multiboot, specify the kernel as -kernel option. Modules should be given
as -initrd options, seperated by a comma (,). -append also works.

Please bear in mind that grub also does gzip decompression, which qemu does
not do yet. To run existing images, please ungzip them first.

The guest multiboot loader code is implemented as option rom using int 19.
Parts of the work are based on efforts by Rene Rebe, who originally ported
my code to int 19.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Multiboot passes options to the option rom using the fw_cfg device.
Right now, that device is local to the bochs_bios_init function.

Let's change that and expose it, so everyone may put data in there.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

For multiboot support, we need bochs_bios_init to happen before
load_linux, so we get the fw_cfg device.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

The KVM kernel will disable all bits in CPUID which are not present in
the host. As this is mostly true for the hypervisor bit (1.ecx),
preserve its value before the trim and restore it afterwards.
Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

KVM provides an in-kernel feature to disable CPUID bits that are not
present in the current host. So there is no need here to duplicate this
work. Additionally allows 3DNow! on capable processors, since the
restriction seems to apply to QEMU/TCG only.
Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

If we want to trim the user provided CPUID bits for KVM to be not greater
than that of the host, we should not remove the bits _after_ we sent
them to the kernel.
This fixes the masking of features that are not present on the host by
moving the trim function and it's call from helper.c to kvm.c.
It helps to use -cpu host.
Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Although the guest's CPUID bits can be controlled in a fine grained way
in QEMU, a simple way to inject the host CPU is missing. This is handy
for KVM desktop virtualization, where one wants the guest to support the
full host feature set.
Introduce another CPU type called 'host', which will propagate the host's
CPUID bits to the guest. Unwanted bits can still be turned off by using
the existing syntax (-cpu host,-skinit)
Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

KVM defaults to the hypervisor CPUID bit to be set, whereas pure
QEMU clears it. On some occasions one wants to set or clear it the
other way round (for instance to get HyperV running inside a guest).

Move the bit-set to be done before the command line parsing and
enable it by default. One can disable it by using: -cpu qemu64,-hypervisor
Fix some whitespace damage on the way.
Signed-off-by: NAndre Przywara <andre.przywara@amd.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Problem: It is impossible to feed filenames with the character colon because
qemu interprets such names as a protocol. For example filename scsi:0, is
interpreted as a protocol by name "scsi".

This patch allows user to espace colon characters. For example the above
filename can now be expressed either as 'scsi\:0' or as file:scsi:0

anything following the "file:" tag is interpreted verbatin. However if "file:"
tag is omitted then any colon characters in the string must be escaped using
backslash.

Here are couple of examples:

scsi\:0\:abc is a local file scsi:0:abc
http\://myweb is a local file by name http://myweb
file:scsi:0:abc is a local file scsi:0:abc
file:http://myweb is a local file by name http://mywebSigned-off-by: NRam Pai <linuxram@us.ibm.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Not every distro provides libcurses anymore, at least OpenSUSE, and at
least under a standard library search path. So try to link against
standard ncurses first and then fall back to legacy curses.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

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

Extend the syntax of hostfwd_add/remove to optionally take a tuple of
VLAN ID and slirp stack name. If those are omitted, the commands will
continue to work on the first registered slirp stack.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Introduce qemu_find_vlan_client_by_name for VLANClientState lookup based
on VLAN ID and client name. This is useful for monitor commands.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Push the smb state, smb_dir, into SlirpState and construct it in a way
that allows multiple smb instances (one per slirp stack). Remove the smb
directory on slirp cleanup instead of qemu termination. As VLAN clients
are also cleaned up on process termination, no feature is lost.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Make sure for invocations from the monitor that slirp_smb properly
reports errors and doesn't terminate qemu.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Instead of open-coding this, we can use the power of the shell to remove
the smb_dir on exit.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

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

Once again this was a long journey to reach the destination: Allow to
instantiate slirp multiple times. But as in the past, the journey was
worthwhile, cleaning up, fixing and enhancing various parts of the user
space network stack along the way.

What is this particular change good for? Multiple slirps instances
allow separated user space networks for guests with multiple NICs. This
is already possible, but without any slirp support for the second
network, ie. without a chance to talk to that network from the host via
IP. We have a legacy guest system here that benefits from this slirp
enhancement, allowing us to run both of its NICs purely over
unprivileged user space IP stacks.

Another benefit of this patch is that it simply removes an artificial
restriction of the configuration space qemu is providing, avoiding
another source of surprises that users may face when playing with
possible setups.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

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>

The essence of this patch is to stuff (almost) all global variables of
the slirp stack into the structure Slirp. In this step, we still keep
the structure as global variable, directly accessible by the whole
stack. Changes to the external interface of slirp will be applied in
the following patches.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

link_up is true once slirp is initialized, so these check are really not
required.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Again lot of dead code. Remove it.
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>

Drop redundant typecasts in both variants and remove the pointless
round-up in the UNIX version.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Currently, ip_id is always initialized to 0 on slirp startup (despite
the broken attempt to derive it from the clock). This is good for
reproducibility. But it is not preserved across save/restore. This patch
therefore drops the dead initialization code from ip_init and introduces
ip_id to the persistent slirp state.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

In order to prepare re-initialization and multi-instance slirp, factor
out init code that is of global scope and (at least for now) only need
to be run once.

This also fixes the potentially uninitialized use of our_addr in
get_dns_addr.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This changes the filename handling from a static buffer in tftp_session
for the client-provided name + prefix to a dynamically allocated buffer
that keeps the combined path in one place.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Specifically make the filename extraction more readable, and always
report errors back to the client.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

The return code of tftp_send_error is not used, drop it. And also make
sure to always terminate the session.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Perform check for set prefix early (if it's not given, tftp is disabled)
and drop redundant second check.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

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

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>

After all its years inside the qemu tree, there is no point in keeping
the dead code paths of slirp. This patch is a first round of removing
usually commented out code parts. More cleanups need to follow (and
maybe finally a proper reindention).
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>

Required for pretty-printing.
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>