There are three page size in qemu:
real host page size
host page size
target page size
All of them have dedicate variable to represent. For the last two, we
use the same form in the whole qemu project, while for the first one we
use two forms: qemu_real_host_page_size and getpagesize().
qemu_real_host_page_size is defined to be a replacement of
getpagesize(), so let it serve the role.
[Note] Not fully tested for some arch or device.
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20191013021145.16011-3-richardw.yang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently libvhost-user is hardcoded to at most 8 virtqueues. The
device backend should decide the number of virtqueues, not
libvhost-user. This is important for multiqueue device backends where
the guest driver needs an accurate number of virtqueues.
This change breaks libvhost-user and libvhost-user-glib API stability.
There is no stability guarantee yet, so make this change now and update
all in-tree library users.
This patch touches up vhost-user-blk, vhost-user-gpu, vhost-user-input,
vhost-user-scsi, and vhost-user-bridge. If the device has a fixed
number of queues that exact number is used. Otherwise the previous
default of 8 virtqueues is used.
vu_init() and vug_init() can now fail if malloc() returns NULL. I
considered aborting with an error in libvhost-user but it should be safe
to instantiate new vhost-user instances at runtime without risk of
terminating the process. Therefore callers need to handle the vu_init()
failure now.
vhost-user-blk and vhost-user-scsi duplicate virtqueue index checks that
are already performed by libvhost-user. This code would need to be
modified to use max_queues but remove it completely instead since it's
redundant.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190626074815.19994-3-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-3-armbru@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
vubr_set_host() passes char values to isdigit(). Undefined behavior
when the value is negative.
Fix by using qemu_isdigit() instead.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190514180311.16028-3-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
[Missing #include "qemu-common.h" fixed]
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes, with the changes
to the following files manually reverted:
contrib/libvhost-user/libvhost-user-glib.h
contrib/libvhost-user/libvhost-user.c
contrib/libvhost-user/libvhost-user.h
linux-user/mips64/cpu_loop.c
linux-user/mips64/signal.c
linux-user/sparc64/cpu_loop.c
linux-user/sparc64/signal.c
linux-user/x86_64/cpu_loop.c
linux-user/x86_64/signal.c
target/s390x/gen-features.c
tests/migration/s390x/a-b-bios.c
tests/test-rcu-simpleq.c
tests/test-rcu-tailq.c
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181204172535.2799-1-armbru@redhat.com>
Acked-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Acked-by: Yuval Shaia <yuval.shaia@oracle.com>
Acked-by: Viktor Prutyanov <viktor.prutyanov@phystech.edu>
After iov_discard_front(), the iov may be smaller than its initial
size. Fixes the heap-buffer-overflow spotted by ASAN:
==9036==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x6060000001e0 at pc 0x7fe632eca3f0 bp 0x7ffddc4a05a0 sp 0x7ffddc49fd48
WRITE of size 32 at 0x6060000001e0 thread T0
#0 0x7fe632eca3ef (/lib64/libasan.so.5+0x773ef)
#1 0x7fe632ecad23 in __interceptor_recvmsg (/lib64/libasan.so.5+0x77d23)
#2 0x561e7491936b in vubr_backend_recv_cb /home/elmarco/src/qemu/tests/vhost-user-bridge.c:333
#3 0x561e74917711 in dispatcher_wait /home/elmarco/src/qemu/tests/vhost-user-bridge.c:160
#4 0x561e7491c3b5 in vubr_run /home/elmarco/src/qemu/tests/vhost-user-bridge.c:725
#5 0x561e7491c85c in main /home/elmarco/src/qemu/tests/vhost-user-bridge.c:806
#6 0x7fe631a6c412 in __libc_start_main (/lib64/libc.so.6+0x24412)
#7 0x561e7491667d in _start (/home/elmarco/src/qemu/build/tests/vhost-user-bridge+0x3967d)
0x6060000001e0 is located 0 bytes to the right of 64-byte region [0x6060000001a0,0x6060000001e0)
allocated by thread T0 here:
#0 0x7fe632f42848 in __interceptor_malloc (/lib64/libasan.so.5+0xef848)
#1 0x561e7493acd8 in virtqueue_alloc_element /home/elmarco/src/qemu/contrib/libvhost-user/libvhost-user.c:1848
#2 0x561e7493c2a8 in vu_queue_pop /home/elmarco/src/qemu/contrib/libvhost-user/libvhost-user.c:1954
#3 0x561e749189bf in vubr_backend_recv_cb /home/elmarco/src/qemu/tests/vhost-user-bridge.c:297
#4 0x561e74917711 in dispatcher_wait /home/elmarco/src/qemu/tests/vhost-user-bridge.c:160
#5 0x561e7491c3b5 in vubr_run /home/elmarco/src/qemu/tests/vhost-user-bridge.c:725
#6 0x561e7491c85c in main /home/elmarco/src/qemu/tests/vhost-user-bridge.c:806
#7 0x7fe631a6c412 in __libc_start_main (/lib64/libc.so.6+0x24412)
SUMMARY: AddressSanitizer: heap-buffer-overflow (/lib64/libasan.so.5+0x773ef)
Shadow bytes around the buggy address:
0x0c0c7fff7fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c0c7fff7ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x0c0c7fff8000: fa fa fa fa 00 00 00 00 00 00 05 fa fa fa fa fa
0x0c0c7fff8010: 00 00 00 00 00 00 00 00 fa fa fa fa fd fd fd fd
0x0c0c7fff8020: fd fd fd fd fa fa fa fa fd fd fd fd fd fd fd fd
=>0x0c0c7fff8030: fa fa fa fa 00 00 00 00 00 00 00 00[fa]fa fa fa
0x0c0c7fff8040: fd fd fd fd fd fd fd fd fa fa fa fa fd fd fd fd
0x0c0c7fff8050: fd fd fd fd fa fa fa fa fd fd fd fd fd fd fd fd
0x0c0c7fff8060: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x0c0c7fff8070: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x0c0c7fff8080: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20181109173028.3372-1-marcandre.lureau@redhat.com>
Signed-off-by: Paolo BOnzini <pbonzini@redhat.com>
This patch introduces the host notifier support in
vhost-user-bridge. A new option (-H) is added to use
the host notifier. This is mainly used to test the
host notifier implementation in vhost user.
Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Use of a do/while(0) loop as a way to allow break statements in
the middle of execute-once code is unusual. More typical is
the use of goto for early exits, with a label at the end of
the execute-once code, rather than nesting code in a scope;
however, the comment at the end of the existing code makes this
alternative a bit unpractical.
So, to avoid false positives from a future syntax check about
'while (false);', and to keep the loop form (in case someone
ever does add DONTWAIT support, where they can just as easily
manipulate the initial loop condition or add an if around the
final 'break'), I opted to use the form of a while(1) loop (the
break as an early exit is more idiomatic there), coupled with
a final break preserving the original comment.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20171201232433.25193-6-eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Only process received packets if the queue has been started.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20171002191521.15748-3-dgilbert@redhat.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Commit e10e798c85 switched to libvhost-user which lacked support
for resuming the avail_idx based on used_idx.
Fixes:
https://bugzilla.redhat.com/show_bug.cgi?id=1485867
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
CC tests/vhost-user-bridge.o
/home/dgilbert/git/qemu-world3/tests/vhost-user-bridge.c:228:23: warning: variables 'front' and 'iov' used in loop condition not modified in loop body [-Wfor-loop-analysis]
for (cur = front; front != iov; cur++) {
^~~~~ ~~~
1 warning generated.
Fix the loop, document the function, and fix some related assert().
In practice, the loop bug was harmless because the front sg buffer is
enough to discard/restore the header size.
Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Tested-by: Jens Freimann <jfreiman@redhat.com>
Use the libvhost-user library.
This ended up being a rather large patch that cannot be easily splitted,
due to massive code move and API changes.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The call fd is not watched
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
dispatcher_remove() is in use.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tracked down with an ugly, brittle and probably buggy Perl script.
Also move includes converted to <...> up so they get included before
ours where that's obviously okay.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Beginning of reconnect support for vhost-user.
Misc cleanups and fixes.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging
pc, pci, virtio: new features, cleanups, fixes
Beginning of reconnect support for vhost-user.
Misc cleanups and fixes.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
# gpg: Signature made Fri 17 Jun 2016 01:28:39 BST
# gpg: using RSA key 0x281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg: aka "Michael S. Tsirkin <mst@redhat.com>"
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17 0970 C350 3912 AFBE 8E67
# Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA 8A0D 281F 0DB8 D28D 5469
* remotes/mst/tags/for_upstream:
MAINTAINERS: add Marcel to PCI
msi_init: change return value to 0 on success
fix some coding style problems
pci core: assert ENOSPC when add capability
test: start vhost-user reconnect test
tests: append i386 tests
vhost-net: save & restore vring enable state
vhost-net: save & restore vhost-user acked features
vhost-net: do not crash if backend is not present
vhost-user: disconnect on start failure
qemu-char: add qemu_chr_disconnect to close a fd accepted by listen fd
tests/vhost-user-bridge: workaround stale vring base
tests/vhost-user-bridge: add client mode
vhost-user: add ability to know vhost-user backend disconnection
pci: fix pci_requester_id()
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Conflicts:
tests/Makefile.include
This patch is a similar solution to what Yuanhan Liu/Huawei Xie have
suggested for DPDK. When vubr quits (killed or crashed), a restart of
vubr would get stale vring base from QEMU. That would break the kernel
virtio net completely, making it non-work any more, unless a driver
reset is done.
So, instead of getting the stale vring base from QEMU, Huawei suggested
we could get a proper one from used->idx. This works because the queues
packets are processed in order.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Victor Kaplansky <victork@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
If -c is specified, vubr will try to connect to the socket instead of
listening for connections.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Victor Kaplansky <victork@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
qemu/osdep.h checks whether MAP_ANONYMOUS is defined, but this check
is bogus without a previous inclusion of sys/mman.h. Include it in
sysemu/os-posix.h and remove it from everywhere else.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Fixes all over the place.
New tests for pxe.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging
vhost, virtio, pci, pxe
Fixes all over the place.
New tests for pxe.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
# gpg: Signature made Thu 18 Feb 2016 15:46:39 GMT using RSA key ID D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg: aka "Michael S. Tsirkin <mst@redhat.com>"
* remotes/mst/tags/for_upstream:
tests/vhost-user-bridge: add scattering of incoming packets
vhost-user interrupt management fixes
rules: filter out irrelevant files
change type of pci_bridge_initfn() to void
dec: convert to realize()
tests: add pxe e1000 and virtio-pci tests
msix: fix msix_vector_masked
virtio: optimize virtio_access_is_big_endian() for little-endian targets
vhost: simplify vhost_needs_vring_endian()
vhost: move virtio 1.0 check to cross-endian helper
virtio: move cross-endian helper to vhost
vhost-net: revert support of cross-endian vnet headers
virtio-net: use the backend cross-endian capabilities
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This patch adds to the vubr test the scattering of incoming
packets to the chain of RX buffer. Also, this patch corrects the
size of the header preceding the packet in RX buffers.
Note that this patch doesn't add the support for mergeable
buffers.
Signed-off-by: Victor Kaplansky <victork@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Eric Blake <eblake@redhat.com>
This fixes file descriptor leakage in vhost-user-bridge
application. Whenever a new callfd or kickfd is set, the previous
one should be explicitly closed. File descriptors used to map
guest's memory are closed immediately after mmap call.
Signed-off-by: Victor Kaplansky <victork@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Now some vhost-user-bridge parameters can be passed from the
command line:
Usage: prog [-u ud_socket_path] [-l lhost:lport] [-r rhost:rport]
-u path to unix doman socket. default: /tmp/vubr.sock
-l local host and port. default: 127.0.0.1:4444
-r remote host and port. default: 127.0.0.1:5555
Signed-off-by: Victor Kaplansky <victork@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The backend has to know whether VIRTIO_NET_F_GUEST_ANNOUNCE was
negotiated, so, as a hack we propose the feature by
vhost-user-bridge during the feature negotiation.
Signed-off-by: Victor Kaplansky <victork@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
During migration devices continue writing to the guest's memory.
The writes has to be reported to QEMU. This change implements
minimal support in vhost-user-bridge required for successful
migration of a guest with virtio-net device.
Signed-off-by: Victor Kaplansky <victork@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This patch basically reverts commit d1f8b30e.
It turned out that it breaks stuff, so revert it:
http://lists.nongnu.org/archive/html/qemu-devel/2015-10/msg00949.html
CC: "Michael S. Tsirkin" <mst@redhat.com>
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The test existing in QEMU for vhost-user feature is good for
testing the management protocol, but does not allow actual
traffic. This patch proposes Vhost-User Bridge application, which
can serve the QEMU community as a comprehensive test by running
real internet traffic by means of vhost-user interface.
Essentially the Vhost-User Bridge is a very basic vhost-user
backend for QEMU. It runs as a standalone user-level process.
For packet processing Vhost-User Bridge uses an additional QEMU
instance with a backend configured by "-net socket" as a shared
VLAN. This way another QEMU virtual machine can effectively
serve as a shared bus by means of UDP communication.
For a more simple setup, the another QEMU instance running the
SLiRP backend can be the same QEMU instance running vhost-user
client.
This Vhost-User Bridge implementation is very preliminary. It is
missing many features. I has been studying vhost-user protocol
internals, so I've written vhost-user-bridge bit by bit as I
progressed through the protocol. Most probably its internal
architecture will change significantly.
To run Vhost-User Bridge application:
1. Build vhost-user-bridge with a regular procedure. This will
create a vhost-user-bridge executable under tests directory:
$ configure; make tests/vhost-user-bridge
2. Ensure the machine has hugepages enabled in kernel with
command line like:
default_hugepagesz=2M hugepagesz=2M hugepages=2048
3. Run Vhost-User Bridge with:
$ tests/vhost-user-bridge
The above will run vhost-user server listening for connections
on UNIX domain socket /tmp/vubr.sock, and will try to connect
by UDP to VLAN bridge to localhost:5555, while listening on
localhost:4444
Run qemu with a virtio-net backed by vhost-user:
$ qemu \
-enable-kvm -m 512 -smp 2 \
-object memory-backend-file,id=mem,size=512M,mem-path=/dev/hugepages,share=on \
-numa node,memdev=mem -mem-prealloc \
-chardev socket,id=char0,path=/tmp/vubr.sock \
-netdev type=vhost-user,id=mynet1,chardev=char0,vhostforce \
-device virtio-net-pci,netdev=mynet1 \
-net none \
-net socket,vlan=0,udp=localhost:4444,localaddr=localhost:5555 \
-net user,vlan=0 \
disk.img
vhost-user-bridge was tested very lightly: it's able to bringup a
linux on client VM with the virtio-net driver, and execute transmits
and receives to the internet. I tested with "wget redhat.com",
"dig redhat.com".
PS. I've consulted DPDK's code for vhost-user during Vhost-User
Bridge implementation.
Signed-off-by: Victor Kaplansky <victork@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
