Send a protocol version as the first message from server, clients must
close communication if they don't support this protocol version. Older
QEMUs should be fine with this change in the protocol since they
overrides their own vm_id on reception of an id associated to no
eventfd.
Signed-off-by: David Marchand <david.marchand@6wind.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[use fifo_update_and_get()]
Reviewed-by: Claudio Fontana <claudio.fontana@huawei.com>
Add some notes on the parts needed to use ivshmem devices: more specifically,
explain the purpose of an ivshmem server and the basic concept to use the
ivshmem devices in guests.
Move some parts of the documentation and re-organise it.
Signed-off-by: David Marchand <david.marchand@6wind.com>
Reviewed-by: Claudio Fontana <claudio.fontana@huawei.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
When using ivshmem devices, notifications between guests can be sent as
interrupts using a ivshmem-server (typical use described in documentation).
The client is provided as a debug tool.
Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
Signed-off-by: David Marchand <david.marchand@6wind.com>
[fix a valgrind warning, option and server_close() segvs, extra server
headers includes, getopt() return type, out-of-tree build, use qemu
event_notifier instead of eventfd, fix x86/osx warnings - Marc-André]
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
When trying to use a ivshmem server with qemu, ivshmem init code tries to
create a CharDriverState object for each eventfd retrieved from the server.
To create this object, a call to qemu_chr_open_eventfd() is done.
Right after this, before adding a frontend, qemu_chr_fe_claim_no_fail() is
called.
qemu_chr_open_eventfd() does not set avail_connections to 1, so no frontend can
be associated because qemu_chr_fe_claim_no_fail() makes qemu stop right away.
This problem comes from 456d606923
"qemu-char: Call fe_claim / fe_release when not using qdev chr properties".
Fix this, by setting avail_connections to 1 in qemu_chr_open_eventfd().
Signed-off-by: David Marchand <david.marchand@6wind.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
David Marchand