Commit Graph

153 Commits

Author SHA1 Message Date
Stefan Hajnoczi
8275e2f6be virtio: fix stray tab character
Fix a single occurrence of a tab character in a file that otherwise uses
spaces for indentation.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-09-23 19:03:55 +03:00
Prasad J Pandit
973e7170dd virtio: add check for descriptor's mapped address
virtio back end uses set of buffers to facilitate I/O operations.
If its size is too large, 'cpu_physical_memory_map' could return
a null address. This would result in a null dereference while
un-mapping descriptors. Add check to avoid it.

Reported-by: Qinghao Tang <luodalongde@gmail.com>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2016-09-23 18:51:40 +03:00
Stefan Hajnoczi
297a75e6c5 virtio: add virtqueue_rewind()
virtqueue_discard() requires a VirtQueueElement but virtio-balloon does
not migrate its in-use element.  Introduce a new function that is
similar to virtqueue_discard() but doesn't require a VirtQueueElement.

This will allow virtio-balloon to access element again after migration
with the usual proviso that the guest may have modified the vring since
last time.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Roman Kagan <rkagan@virtuozzo.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-09-09 20:58:34 +03:00
Stefan Hajnoczi
4b7f91ed02 virtio: zero vq->inuse in virtio_reset()
vq->inuse must be zeroed upon device reset like most other virtqueue
fields.

In theory, virtio_reset() just needs assert(vq->inuse == 0) since
devices must clean up in-flight requests during reset (requests cannot
not be leaked!).

In practice, it is difficult to achieve vq->inuse == 0 across reset
because balloon, blk, 9p, etc implement various different strategies for
cleaning up requests.  Most devices call g_free(elem) directly without
telling virtio.c that the VirtQueueElement is cleaned up.  Therefore
vq->inuse is not decremented during reset.

This patch zeroes vq->inuse and trusts that devices are not leaking
VirtQueueElements across reset.

I will send a follow-up series that refactors request life-cycle across
all devices and converts vq->inuse = 0 into assert(vq->inuse == 0) but
this more invasive approach is not appropriate for stable trees.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Cc: qemu-stable <qemu-stable@nongnu.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Ladi Prosek <lprosek@redhat.com>
2016-09-09 20:58:34 +03:00
Stefan Hajnoczi
58a83c6149 virtio: decrement vq->inuse in virtqueue_discard()
virtqueue_discard() moves vq->last_avail_idx back so the element can be
popped again.  It's necessary to decrement vq->inuse to avoid "leaking"
the element count.

Cc: qemu-stable@nongnu.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-08-23 19:20:24 +03:00
Stefan Hajnoczi
bccdef6b1a virtio: recalculate vq->inuse after migration
The vq->inuse field is not migrated.  Many devices don't hold
VirtQueueElements across migration so it doesn't matter that vq->inuse
starts at 0 on the destination QEMU.

At least virtio-serial, virtio-blk, and virtio-balloon migrate while
holding VirtQueueElements.  For these devices we need to recalculate
vq->inuse upon load so the value is correct.

Cc: qemu-stable@nongnu.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-08-23 19:20:10 +03:00
Peter Maydell
cbe81c6331 pc, pci, virtio: cleanups, fixes
a bunch of bugfixes and a couple of cleanups
 making these easier and/or making debugging easier
 
 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: cleanups, fixes

a bunch of bugfixes and a couple of cleanups
making these easier and/or making debugging easier

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Fri 29 Jul 2016 04:11:01 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: (41 commits)
  mptsas: Fix a migration compatible issue
  vhost: do not update last avail idx on get_vring_base() failure
  vhost: add vhost_net_set_backend()
  vhost-user: add error report in vhost_user_write()
  tests: fix vhost-user-test leak
  tests: plug some leaks in virtio-net-test
  vhost-user: wait until backend init is completed
  char: add and use tcp_chr_wait_connected
  char: add chr_wait_connected callback
  vhost: add assert() to check runtime behaviour
  vhost-net: vhost_migration_done is vhost-user specific
  Revert "vhost-net: do not crash if backend is not present"
  vhost-user: add get_vhost_net() assertions
  vhost-user: keep vhost_net after a disconnection
  vhost-user: check vhost_user_{read,write}() return value
  vhost-user: check qemu_chr_fe_set_msgfds() return value
  vhost-user: call set_msgfds unconditionally
  qemu-char: fix qemu_chr_fe_set_msgfds() crash when disconnected
  vhost: use error_report() instead of fprintf(stderr,...)
  vhost: add missing VHOST_OPS_DEBUG
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-07-29 11:57:01 +01:00
Prasad J Pandit
1e7aed7014 virtio: check vring descriptor buffer length
virtio back end uses set of buffers to facilitate I/O operations.
An infinite loop unfolds in virtqueue_pop() if a buffer was
of zero size. Add check to avoid it.

Reported-by: Li Qiang <liqiang6-s@360.cn>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-29 00:07:10 +03:00
Stefan Hajnoczi
afd9096eb1 virtio: error out if guest exceeds virtqueue size
A broken or malicious guest can submit more requests than the virtqueue
size permits, causing unbounded memory allocation in QEMU.

The guest can submit requests without bothering to wait for completion
and is therefore not bound by virtqueue size.  This requires reusing
vring descriptors in more than one request, which is not allowed by the
VIRTIO 1.0 specification.

In "3.2.1 Supplying Buffers to The Device", the VIRTIO 1.0 specification
says:

  1. The driver places the buffer into free descriptor(s) in the
     descriptor table, chaining as necessary

and

  Note that the above code does not take precautions against the
  available ring buffer wrapping around: this is not possible since the
  ring buffer is the same size as the descriptor table, so step (1) will
  prevent such a condition.

This implies that placing more buffers into the virtqueue than the
descriptor table size is not allowed.

QEMU is missing the check to prevent this case.  Processing a request
allocates a VirtQueueElement leading to unbounded memory allocation
controlled by the guest.

Exit with an error if the guest provides more requests than the
virtqueue size permits.  This bounds memory allocation and makes the
buggy guest visible to the user.

This patch fixes CVE-2016-5403 and was reported by Zhenhao Hong from 360
Marvel Team, China.

Reported-by: Zhenhao Hong <hongzhenhao@360.cn>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-27 14:04:40 +01:00
Dr. David Alan Gilbert
5943124cc0 virtio: Migration helper function and macro
To make conversion of virtio devices to VMState simple
at first add a helper function for the simple virtio_save
case and a helper macro that defines the VMState structure.
These will probably go away or change as more of the virtio
code gets converted.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-21 20:44:19 +03:00
Fam Zheng
872dd82c83 virtio: Introduce virtio_add_queue_aio
Using this function instead of virtio_add_queue marks the vq as aio
based. This differentiation will be useful in later patches.

Distinguish between virtqueue processing in the iohandler context and main loop
AioContext.  iohandler context is isolated from AioContexts and therefore does
not run during aio_poll().

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-21 20:44:19 +03:00
Fam Zheng
bf1780b0d5 virtio: Add typedef for handle_output
The function pointer signature has been repeated a few times, using a
typedef may make coding easier.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-21 20:44:19 +03:00
Michael S. Tsirkin
62cee1a28a virtio: set low features early on load
virtio migrates the low 32 feature bits twice, the first copy is there
for compatibility but ever since
019a3edbb2: ("virtio: make features 64bit
wide") it's ignored on load. This is wrong since virtio_net_load tests
self announcement and guest offloads before the second copy including
high feature bits is loaded.  This means that self announcement, control
vq and guest offloads are all broken after migration.

Fix it up by loading low feature bits: somewhat ugly since high and low
bits become out of sync temporarily, but seems unavoidable for
compatibility.  The right thing to do for new features is probably to
test the host features, anyway.

Fixes: 019a3edbb2
    ("virtio: make features 64bit wide")
Cc: qemu-stable@nongnu.org
Reported-by: Robin Geuze <robing@transip.nl>
Tested-by: Robin Geuze <robing@transip.nl>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-04 14:52:10 +03:00
Stefan Hajnoczi
3a90c4ace2 virtio: drop duplicate virtio_queue_get_id() function
The virtio_queue_get_id() function is the lesser used duplicate of
virtio_get_queue_index().  Use the latter instead.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1463767461-17922-1-git-send-email-stefanha@redhat.com
2016-06-07 14:40:51 +01:00
Fam Zheng
14560d69e7 virtio: Mark host notifiers as external
The effect of this change is the block layer drained section can work,
for example when mirror job is being completed.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-04-22 16:43:58 +02:00
Fam Zheng
54e18d35e4 event-notifier: Add "is_external" parameter
All callers pass "false" keeping the old semantics. The windows
implementation doesn't distinguish the flag yet. On posix, it is passed
down to the underlying aio context.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-04-22 16:43:56 +02:00
Paolo Bonzini
a378b49a43 virtio: merge virtio_queue_aio_set_host_notifier_handler with virtio_queue_set_aio
Eliminating the reentrancy is actually a nice thing that we can do
with the API that Michael proposed, so let's make it first class.
This also hides the complex assign/set_handler conventions from
callers of virtio_queue_aio_set_host_notifier_handler, which in
fact was always called with assign=true.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-04-07 19:57:33 +03:00
Michael S. Tsirkin
344dc16fae virtio: add aio handler
In addition to handling IO in vcpu thread and in io thread, blk dataplane
introduces yet another mode: handling it by AioContext.

Currently, this reuses the same handler as previous modes,
which triggers races as these were not designed to be reentrant.
Add instead a separate handler just for aio; this will make
it possible to disable regular handlers when dataplane is active.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-04-07 19:57:33 +03:00
Paolo Bonzini
2b2cbcadc1 virtio: make virtio_queue_notify_vq static
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-04-07 19:57:33 +03:00
Paolo Bonzini
4771d756f4 hw: explicitly include qemu-common.h and cpu.h
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:17 +01:00
Markus Armbruster
da34e65cb4 include/qemu/osdep.h: Don't include qapi/error.h
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef.  Since then, we've moved to include qemu/osdep.h
everywhere.  Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h.  That's in excess of
100KiB of crap most .c files don't actually need.

Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h.  Include qapi/error.h in .c files that need it and don't
get it now.  Include qapi-types.h in qom/object.h for uint16List.

Update scripts/clean-includes accordingly.  Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h.  Update the list of includes in the qemu/osdep.h
comment quoted above similarly.

This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third.  Unfortunately, the number depending on
qapi-types.h shrinks only a little.  More work is needed for that one.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:15 +01:00
Paolo Bonzini
adb3feda8d virtio: export vring_notify as virtio_should_notify
Virtio dataplane needs to trigger the irq manually through the
guest notifier.  Export virtio_should_notify so that it can be
used around event_notifier_set.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-02-25 13:14:18 +02:00
Paolo Bonzini
a1afb6062e virtio: add AioContext-specific function for host notifiers
This is used to register ioeventfd with a dataplane thread.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-02-25 13:14:18 +02:00
Victor Kaplansky
5669655aaf vhost-user interrupt management fixes
Since guest_mask_notifier can not be used in vhost-user mode due
to buffering implied by unix control socket, force
use_mask_notifier on virtio devices of vhost-user interfaces, and
send correct callfd to the guest at vhost start.

Using guest_notifier_mask function in vhost-user case may
break interrupt mask paradigm, because mask/unmask is not
really done when returning from guest_notifier_mask call, instead
message is posted in a unix socket, and processed later.

Add an option boolean flag 'use_mask_notifier' to disable the use
of guest_notifier_mask in virtio pci.

Signed-off-by: Didier Pallard <didier.pallard@6wind.com>
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>
2016-02-18 16:13:56 +02:00
Vincenzo Maffione
1cdd2ee54a virtio: combine write of an entry into used ring
Fill in an element of the used ring with a single combined access to the
guest physical memory, rather than using two separated accesses.
This reduces the overhead due to expensive address translation.

Signed-off-by: Vincenzo Maffione <v.maffione@gmail.com>
Message-Id: <e4a89a767a4a92cbb6bcc551e151487eb36e1722.1450218353.git.v.maffione@gmail.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-02-06 20:44:08 +02:00
Vincenzo Maffione
be1fea9bc2 virtio: read avail_idx from VQ only when necessary
The virtqueue_pop() implementation needs to check if the avail ring
contains some pending buffers. To perform this check, it is not
always necessary to fetch the avail_idx in the VQ memory, which is
expensive. This patch introduces a shadow variable tracking avail_idx
and modifies virtio_queue_empty() to access avail_idx in physical
memory only when necessary.

Signed-off-by: Vincenzo Maffione <v.maffione@gmail.com>
Message-Id: <b617d6459902773d9f4ab843bfaca764f5af8eda.1450218353.git.v.maffione@gmail.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-02-06 20:44:08 +02:00
Vincenzo Maffione
b796fcd1bf virtio: cache used_idx in a VirtQueue field
Accessing used_idx in the VQ requires an expensive access to
guest physical memory. Before this patch, 3 accesses are normally
done for each pop/push/notify call. However, since the used_idx is
only written by us, we can track it in our internal data structure.

Signed-off-by: Vincenzo Maffione <v.maffione@gmail.com>
Message-Id: <3d062ec54e9a7bf9fb325c1fd693564951f2b319.1450218353.git.v.maffione@gmail.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-02-06 20:44:08 +02:00
Paolo Bonzini
aa570d6fb6 virtio: combine the read of a descriptor
Compared to vring, virtio has a performance penalty of 10%.  Fix it
by combining all the reads for a descriptor in a single address_space_read
call.  This also simplifies the code nicely.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-02-06 20:44:08 +02:00
Paolo Bonzini
3b3b062821 virtio: slim down allocation of VirtQueueElements
Build the addresses and s/g lists on the stack, and then copy them
to a VirtQueueElement that is just as big as required to contain this
particular s/g list.  The cost of the copy is minimal compared to that
of a large malloc.

When virtqueue_map is used on the destination side of migration or on
loadvm, the iovecs have already been split at memory region boundary,
so we can just reuse the out_num/in_num we find in the file.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-02-06 20:44:08 +02:00
Paolo Bonzini
3724650db0 virtio: introduce virtqueue_alloc_element
Allocate the arrays for in_addr/out_addr/in_sg/out_sg outside the
VirtQueueElement.  For now, virtqueue_pop and vring_pop keep
allocating a very large VirtQueueElement.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-02-06 20:44:08 +02:00
Paolo Bonzini
ab281c1781 virtio: introduce qemu_get/put_virtqueue_element
Move allocation to virtio functions also when loading/saving a
VirtQueueElement.  This will also let the load/save functions
keep backwards compatibility when the VirtQueueElement layout
is changed.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-02-06 20:44:08 +02:00
Paolo Bonzini
51b19ebe43 virtio: move allocation to virtqueue_pop/vring_pop
The return code of virtqueue_pop/vring_pop is unused except to check for
errors or 0.  We can thus easily move allocation inside the functions
and just return a pointer to the VirtQueueElement.

The advantage is that we will be able to allocate only the space that
is needed for the actual size of the s/g list instead of the full
VIRTQUEUE_MAX_SIZE items.  Currently VirtQueueElement takes about 48K
of memory, and this kind of allocation puts a lot of stress on malloc.
By cutting the size by two or three orders of magnitude, malloc can
use much more efficient algorithms.

The patch is pretty large, but changes to each device are testable
more or less independently.  Splitting it would mostly add churn.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-02-06 20:39:07 +02:00
Dr. David Alan Gilbert
3e996cc583 Fix virtio migration
I misunderstood the vmstate macro definition when I reworked the
virtio .get/.put.
The VMSTATE_STRUCT_VARRAY_KNOWN, was described as being for "a
variable length array (i.e. _type *_field) but we know the
length".  However it actually specified operation for arrays embedded in
the struct (i.e. _type _field[]) since it lacked the VMS_POINTER
flag. This caused offset calculation to be completely off, examining and
potentially sending random data instead of the VirtQueue content.

Replace the otherwise unused VMSTATE_STRUCT_VARRAY_KNOWN with a
VMSTATE_STRUCT_VARRAY_POINTER_KNOWN that includes the VMS_POINTER flag
(so now actually doing what it advertises) and use it in the virtio
migration code.

Fixes and description as per Sascha's suggestions/debug.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reported-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Tested-By: Sascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-By: Sascha Silbe <silbe@linux.vnet.ibm.com>

Fixes: 50e5ae4dc3
Fixes: 2cf0148674
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-02-04 19:53:02 +02:00
Peter Maydell
9b8bfe21be virtio: Clean up includes
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>
Message-id: 1453832250-766-15-git-send-email-peter.maydell@linaro.org
2016-01-29 15:07:23 +00:00
Cornelia Huck
8a1be662a6 virtio: fix error message for number of queues
There's no such thing as "PCI queues" in the virtio core.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-01-09 23:20:20 +02:00
Dr. David Alan Gilbert
50e5ae4dc3 migration/virtio: Remove simple .get/.put use
The 'virtqueue_state' and 'ringsize' can be saved using VMSTATE
macros rather than hand coded .get/.put

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
2016-01-09 23:20:20 +02:00
Jason Wang
a6df8adf3e virtio-pci: fix 1.0 virtqueue migration
We don't migrate the followings fields for virtio-pci:

uint32_t dfselect;
uint32_t gfselect;
uint32_t guest_features[2];
struct {
    uint16_t num;
    bool enabled;
    uint32_t desc[2];
    uint32_t avail[2];
    uint32_t used[2];
} vqs[VIRTIO_QUEUE_MAX];

This will confuse driver if migrating during initialization. Solves
this issue by:

- introduce transport specific callbacks to load and store extra
  virtqueue states.
- add a new subsection for virtio to migrate transport specific modern
  device state.
- implement pci specific callbacks.
- add a new property for virtio-pci for whether or not to migrate
  extra state.
- compat the migration for 2.4 and elder machine types

Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-11-12 15:49:32 +02:00
Michael S. Tsirkin
3945ecf1ec virtio: drop virtqueue_map_sg
Deprecated in favor of virtqueue_map.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
2015-10-29 11:05:24 +02:00
Michael S. Tsirkin
13972ac5e2 virtio: switch to virtio_map
Drop use of the deprecated virtio_map_sg in virtio core.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
2015-10-29 11:05:24 +02:00
Michael S. Tsirkin
8059feee00 virtio: introduce virtio_map
virtio_map_sg currently fails if one of the entries it's mapping is
contigious in GPA but not HVA address space.  Introduce virtio_map which
handles this by splitting sg entries.

This new API generally turns out to be a good idea since it's harder to
misuse: at least in one case the existing one was used incorrectly.

This will still fail if there's no space left in the sg, but luckily max
queue size in use is currently 256, while max sg size is 1024, so we
should be OK even is all entries happen to cross a single DIMM boundary.

Won't work well with very small DIMM sizes, unfortunately:
e.g. this will fail with 4K DIMMs where a single
request might span a large number of DIMMs.

Let's hope these are uncommon - at least we are not breaking things.

Note: virtio-scsi calls virtio_map_sg on data loaded from network, and
validates input, asserting on failure.  Copy the validating code here -
it will be dropped from virtio-scsi in a follow-up patch.

Reported-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
2015-10-29 11:05:24 +02:00
Jason Wang
29b9f5efd7 virtio: introduce virtqueue_discard()
This patch introduces virtqueue_discard() to discard a descriptor and
unmap the sgs. This will be used by the patch that will discard
descriptor when packet is truncated.

Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-10-01 16:16:52 +03:00
Jason Wang
ce31746157 virtio: introduce virtqueue_unmap_sg()
Factor out sg unmapping logic. This will be reused by the patch that
can discard descriptor.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Andrew James <andrew.james@hpe.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-10-01 16:16:52 +03:00
Cornelia Huck
46c5d0823d virtio: ring sizes vs. reset
We allow guests to change the size of the virtqueue rings by supplying
a number of buffers that is different from the number of buffers the
device was initialized with. Current code has some problems, however,
since reset does not reset the ringsizes to the default values (as this
is not saved anywhere).

Let's extend the core code to keep track of the default ringsizes and
migrate them once the guest changed them for any of the virtqueues
for a device.

Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-09-24 13:42:17 +03:00
Pierre Morel
50764fc8a3 virtio: right size for virtio_queue_get_avail_size
Being working on dataplane I notice something strange:

virtio_queue_get_avail_size() used a 64bit size index
for the calculation of the available ring size.

It is quite strange but it did work with the old calculation
of the avail ring, at most with performance penalty,
and I wonder where I missed something.

This patch let use a 16bit size as defined in virtio_ring.h

Signed-off-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-09-24 13:39:46 +03:00
Cornelia Huck
95129d6fc9 virtio: avoid leading underscores for helpers
Commit ef546f1275 ("virtio: add
feature checking helpers") introduced a helper __virtio_has_feature.
We don't want to use reserved identifiers, though, so let's
rename __virtio_has_feature to virtio_has_feature and virtio_has_feature
to virtio_vdev_has_feature.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-09-10 11:06:05 +03:00
Jason Wang
74aae7b22b virtio: fix 1.0 virtqueue migration
1.0 does not requires physically-contiguous pages layout for a
virtqueue. So we could not infer avail and used from desc. This means
we need to migrate vring.avail and vring.used when host support virtio
1.0. This fixes malfunction of virtio 1.0 device after migration.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-08-05 16:56:34 +03:00
Juan Quintela
5cd8cadae8 migration: Use normal VMStateDescriptions for Subsections
We create optional sections with this patch.  But we already have
optional subsections.  Instead of having two mechanism that do the
same, we can just generalize it.

For subsections we just change:

- Add a needed function to VMStateDescription
- Remove VMStateSubsection (after removal of the needed function
  it is just a VMStateDescription)
- Adjust the whole tree, moving the needed function to the corresponding
  VMStateDescription

Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-06-12 06:53:57 +02:00
Michael S. Tsirkin
adfb743c90 virtio: add modern config accessors
virtio 1.0 defines config space as LE,
as opposed to pre-1.0 which was native endian.

Add API for transports to execute word/dword accesses in
little endian format - will be useful for mmio
and pci (byte access is also wrapped, for completeness).

For simplicity, we still keep config in host native
endian format, byteswap to LE on guest access.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-10 18:15:05 +02:00
Michael S. Tsirkin
b8f059081d virtio: generation counter support
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-10 18:15:05 +02:00
Cornelia Huck
0b352fd680 virtio: allow to fail setting status
virtio-1 allow setting of the FEATURES_OK status bit to fail if
the negotiated feature bits are inconsistent: let's fail
virtio_set_status() in that case and update virtio-ccw to post an
error to the guest.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-10 18:15:04 +02:00
Cornelia Huck
6c0196d702 virtio: disallow late feature changes for virtio-1
For virtio-1 devices, the driver must not attempt to set feature bits
after it set FEATURES_OK in the device status. Simply reject it in
that case.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-10 18:15:04 +02:00
Cornelia Huck
ab223c9518 virtio: allow virtio-1 queue layout
For virtio-1 devices, we allow a more complex queue layout that doesn't
require descriptor table and rings on a physically-contigous memory area:
add virtio_queue_set_rings() to allow transports to set this up.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-10 18:15:04 +02:00
Cornelia Huck
3c185597c8 virtio: endianness checks for virtio 1.0 devices
Add code that checks for the VERSION_1 feature bit in order to make
decisions about the device's endianness. This allows us to support
transitional devices.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-10 18:15:04 +02:00
Gerd Hoffmann
d5aaa1b045 virtio: 64bit features fixups.
Commit "019a3ed virtio: make features 64bit wide" missed a few changes,
as I've noticed while trying to rebase the virtio-1 branch to latest
master.  This patch adds them.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-03 18:19:16 +02:00
Gerd Hoffmann
019a3edbb2 virtio: make features 64bit wide
Make features 64bit wide everywhere.

On migration a full 64bit guest_features field is sent if one of the
high bits is set, in addition to the lower 32bit guest_features field
which must stay for compatibility reasons.  That way we send the lower
32 feature bits twice, but the code is simpler because we don't have
to split and compose the 64bit features into two 32bit fields.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-01 14:18:55 +02:00
Jason Wang
87b3bd1c85 virtio: rename VIRTIO_PCI_QUEUE_MAX to VIRTIO_QUEUE_MAX
VIRTIO_PCI_QUEUE_MAX is not only used for pci, so rename it be generic.

Cc: Amit Shah <amit.shah@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-05-31 16:50:10 +02:00
Jason Wang
8ad176aaed virtio: introduce virtio_get_num_queues()
This patch introduces virtio_get_num_queues() which iterates the vqs
array and return the number of virtqueues used by device.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-05-31 16:45:38 +02:00
Jason Wang
e83980455c virtio: device_plugged() can fail
This patch passes error pointer to transport specific device_plugged()
callback. Through this way, device_plugged() can do some transport
specific check and fail. This will be uesd by following patches that
check the number of virtqueues against the transport limitation.

Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Alexander Graf <agraf@suse.de>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-05-31 16:44:12 +02:00
Cornelia Huck
6b8f102054 virtio: move host_features
Move host_features from the individual transport proxies into
the virtio device. Transports may continue to add feature bits
during device plugging.

This should it make easier to offer different sets of host features
for virtio-1/transitional support.

Tested-by: Shannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-05-31 16:27:18 +02:00
Jason Wang
e0d686bf4b virtio: introduce vector to virtqueues mapping
Currently we will try to traverse all virtqueues to find a subset that
using a specific vector. This is sub optimal when we will support
hundreds or even thousands of virtqueues. So this patch introduces a
method which could be used by transport to get all virtqueues that
using a same vector. This is done through QLISTs and the number of
QLISTs was queried through a transport specific method. When guest
setting vectors, the virtqueue will be linked and helpers for traverse
the list was also introduced.

The first user will be virtio pci which will use this to speed up
MSI-X masking and unmasking handling.

Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-04-27 21:02:41 +02:00
Jason Wang
9e0f5b8108 virtio: validate the existence of handle_output before calling it
We don't validate the existence of handle_output which may let a buggy
guest to trigger a SIGSEV easily. E.g:

1) write 10 to queue_sel to a virtio net device with only 1 queue
2) setup an arbitrary pfn
3) then notify queue 10

Fixing this by validating the existence of handle_output before.

Cc: qemu-stable@nongnu.org
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Don Koch <dkoch@verizon.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2015-03-16 15:29:51 +01:00
Cornelia Huck
ef546f1275 virtio: add feature checking helpers
Add a helper function for checking whether a bit is set in the guest
features for a vdev as well as one that works on a feature bit set.

Convert code that open-coded this: It cleans up the code and makes it
easier to extend the guest feature bits.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-02-26 13:04:07 +01:00
Michael S. Tsirkin
e9600c6ca9 virtio: use standard-headers
Drop a bunch of code duplicated from virtio_config.h and virtio_ring.h.
This makes us rename event index accessors which conflict,
as reusing the ones from virtio_ring.h isn't trivial.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
2015-02-26 13:04:03 +01:00
Alexander Graf
8118f0950f migration: Append JSON description of migration stream
One of the annoyances of the current migration format is the fact that
it's not self-describing. In fact, it's not properly describing at all.
Some code randomly scattered throughout QEMU elaborates roughly how to
read and write a stream of bytes.

We discussed an idea during KVM Forum 2013 to add a JSON description of
the migration protocol itself to the migration stream. This patch
adds a section after the VM_END migration end marker that contains
description data on what the device sections of the stream are composed of.

This approach is backwards compatible with any QEMU version reading the
stream, because QEMU just stops reading after the VM_END marker and ignores
any data following it.

With an additional external program this allows us to decipher the
contents of any migration stream and hopefully make migration bugs easier
to track down.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-02-05 17:16:14 +01:00
Bin Wu
a3614c65cf hw/virtio/vring/event_idx: fix the vring_avail_event error
The event idx in virtio is an effective way to reduce the number of
interrupts and exits of the guest. When the guest puts an request
into the virtio ring, it doesn't exit immediately to inform the
backend. Instead, the guest checks the "avail" event idx to determine
the notification.

In virtqueue_pop, when a request is poped, the current avail event
idx should be set to the number of vq->last_avail_idx.

Signed-off-by: Bin Wu <wu.wubin@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-02 13:44:12 +02:00
Gonglei
c8075caf19 virtio: add a wrapper for virtio-backend initialization
For better code sharing, add a helper function that handles
reference counting of the virtio backend for virtio proxy devices.

Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-30 11:09:59 +02:00
Michael S. Tsirkin
9e8e8c4865 Revert "virtio: don't call device on !vm_running"
This reverts commit a1bc7b827e422e1ff065640d8ec5347c4aadfcd8.
    virtio: don't call device on !vm_running
It turns out that virtio net assumes that vm_running
is updated before device status callback in many places,
so this change leads to asserts.
Previous commit fixes the root issue that motivated
a1bc7b827e422e1ff065640d8ec5347c4aadfcd8 differently,
so there's no longer a need for this change.

In the future, we might be able to drop checking vm_running
completely, and check vm state directly.

Reported-by: Dietmar Maurer <dietmar@proxmox.com>
Cc: qemu-stable@nongnu.org
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-09-18 21:51:24 +03:00
Michael S. Tsirkin
269bd822e7 virtio: don't call device on !vm_running
On vm stop, virtio changes vm_running state
too soon, so callbacks can get envoked with
vm_running = false;

Cc: qemu-stable@nongnu.org
Cc: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-04 17:19:09 +01:00
Rusty Russell
cee3ca0028 virtio: allow byte swapping for vring
Quoting original text from Rusty: "This is based on a simpler patch by Anthony
Liguouri".

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
[ add VirtIODevice * argument to most helpers,
  Greg Kurz <gkurz@linux.vnet.ibm.com> ]
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-29 19:39:42 +03:00
Greg Kurz
616a655219 virtio: add endian-ambivalent support to VirtIODevice
Some CPU families can dynamically change their endianness. This means we
can have little endian ppc or big endian arm guests for example. This has
an impact on legacy virtio data structures since they are target endian.
We hence introduce a new property to track the endianness of each virtio
device. It is reasonnably assumed that endianness won't change while the
device is in use : we hence capture the device endianness when it gets
reset.

We migrate this property in a subsection, after the device descriptor. This
means the load code must not rely on it until it is restored. As a consequence,
the vring sanity checks had to be moved after the call to vmstate_load_state().
We enforce paranoia by poisoning the property at the begining of virtio_load().

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-29 19:39:42 +03:00
Greg Kurz
6b321a3df5 virtio: add subsections to the migration stream
There is a need to add some more fields to VirtIODevice that should be
migrated (broken status, endianness). The problem is that we do not
want to break compatibility while adding a new feature... This issue has
been addressed in the generic VMState code with the use of optional
subsections. As a *temporary* alternative to port the whole virtio
migration code to VMState, this patch mimics a similar subsectionning
ability for virtio, using the VMState code.

Since each virtio device is streamed in its own section, the idea is to
stream subsections between the end of the device section and the start
of the next sections. This allows an older QEMU to complain and exit
when fed with subsections:

Unknown savevm section type 5
load of migration failed

Suggested-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-29 19:39:42 +03:00
Greg Kurz
1b5fc0dea4 virtio: introduce device specific migration calls
In order to migrate virtio subsections, they should be streamed after
the device itself. We need the device specific code to be called from
the common migration code to achieve this. This patch introduces load
and save methods for this purpose.

Suggested-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-29 19:39:41 +03:00
Dr. David Alan Gilbert
2f5732e964 Allow mismatched virtio config-len
Commit 'virtio: validate config_len on load' restricted config_len
loaded from the wire to match the config_len that the device had.

Unfortunately, there are cases where this isn't true, the one
we found it on was the wce addition in virtio-blk.

Allow mismatched config-lengths:
   *) If the version on the wire is shorter then fine
   *) If the version on the wire is longer, load what we have space
      for and skip the rest.

(This is mst@redhat.com's rework of what I originally posted)

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-29 18:59:41 +03:00
Markus Armbruster
80e0090a44 virtio: Drop superfluous conditionals around g_strdup()
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2014-06-19 16:41:53 +03:00
Markus Armbruster
9e28840658 virtio: Drop superfluous conditionals around g_free()
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2014-06-19 16:41:53 +03:00
Michael Tokarev
1a2858995d virtio.c: fix error message
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-06-10 20:07:01 +04:00
Michael S. Tsirkin
9372514080 virtio: allow mapping up to max queue size
It's a loop from i < num_sg  and the array is VIRTQUEUE_MAX_SIZE - so
it's OK if the value read is VIRTQUEUE_MAX_SIZE.

Not a big problem in practice as people don't use
such big queues, but it's inelegant.

Reported-by: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-05-12 12:07:21 +03:00
Michael S. Tsirkin
a890a2f913 virtio: validate config_len on load
Malformed input can have config_len in migration stream
exceed the array size allocated on destination, the
result will be heap overflow.

To fix, that config_len matches on both sides.

CVE-2014-0182

Reported-by: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

--

v2: use %ix and %zx to print config_len values
Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05 22:15:03 +02:00
Michael S. Tsirkin
36cf2a3713 virtio: validate num_sg when mapping
CVE-2013-4535
CVE-2013-4536

Both virtio-block and virtio-serial read,
VirtQueueElements are read in as buffers, and passed to
virtqueue_map_sg(), where num_sg is taken from the wire and can force
writes to indicies beyond VIRTQUEUE_MAX_SIZE.

To fix, validate num_sg.

Reported-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05 22:15:02 +02:00
Michael Roth
4b53c2c72c virtio: avoid buffer overrun on incoming migration
CVE-2013-6399

vdev->queue_sel is read from the wire, and later used in the
emulation code as an index into vdev->vq[]. If the value of
vdev->queue_sel exceeds the length of vdev->vq[], currently
allocated to be VIRTIO_PCI_QUEUE_MAX elements, subsequent PIO
operations such as VIRTIO_PCI_QUEUE_PFN can be used to overrun
the buffer with arbitrary data originating from the source.

Fix this by failing migration if the value from the wire exceeds
VIRTIO_PCI_QUEUE_MAX.

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05 22:15:02 +02:00
Michael S. Tsirkin
cc45995294 virtio: out-of-bounds buffer write on invalid state load
CVE-2013-4151 QEMU 1.0 out-of-bounds buffer write in
virtio_load@hw/virtio/virtio.c

So we have this code since way back when:

    num = qemu_get_be32(f);

    for (i = 0; i < num; i++) {
        vdev->vq[i].vring.num = qemu_get_be32(f);

array of vqs has size VIRTIO_PCI_QUEUE_MAX, so
on invalid input this will write beyond end of buffer.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05 22:15:02 +02:00
Edgar E. Iglesias
5ce5944dc0 exec: Make stw_*_phys input an AddressSpace
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-02-11 22:57:32 +10:00
Edgar E. Iglesias
ab1da85791 exec: Make stl_*_phys input an AddressSpace
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-02-11 22:57:18 +10:00
Edgar E. Iglesias
41701aa4ee exec: Make lduw_*_phys input an AddressSpace
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-02-11 22:57:06 +10:00
Edgar E. Iglesias
2c17449b30 exec: Make ldq/ldub_*_phys input an AddressSpace
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-02-11 22:57:00 +10:00
Edgar E. Iglesias
fdfba1a298 exec: Make ldl_*_phys input an AddressSpace
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-02-11 22:56:54 +10:00
Paolo Bonzini
83d0704734 virtio: add back call to virtio_bus_device_unplugged
This got lost in a rebase.

Reported-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-12-23 18:02:23 +02:00
Andreas Färber
306ec6c3ce virtio: Convert exit to unrealize
Signed-off-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-12-09 21:46:49 +01:00
Andreas Färber
0ba94b6f94 virtio: Complete converting VirtioDevice to QOM realize
Drop VirtioDeviceClass::init.

Signed-off-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-12-09 21:46:49 +01:00
Andreas Färber
1d244b42d2 virtio: Start converting VirtioDevice to QOM realize
Temporarily allow either VirtioDeviceClass::init or
VirtioDeviceClass::realize.

Introduce VirtioDeviceClass::unrealize for symmetry.

Signed-off-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-12-09 21:46:49 +01:00
Paolo Bonzini
5e96f5d2f8 virtio-bus: cleanup plug/unplug interface
Right now we have these pairs:

- virtio_bus_plug_device/virtio_bus_destroy_device.  The first
  takes a VirtIODevice, the second takes a VirtioBusState

- device_plugged/device_unplug callbacks in the VirtioBusClass
  (here it's just the naming that is inconsistent)

- virtio_bus_destroy_device is not called by anyone (and since
  it calls qdev_free, it would be called by the proxies---but
  then the callback is useless since the proxies can do whatever
  they want before calling virtio_bus_destroy_device)

And there is a k->init but no k->exit, hence virtio_device_exit is
overwritten by subclasses (except virtio-9p).  This cleans it up by:

- renaming the device_unplug callback to device_unplugged

- renaming virtio_bus_plug_device to virtio_bus_device_plugged,
  matching the callback name

- renaming virtio_bus_destroy_device to virtio_bus_device_unplugged,
  removing the qdev_free, making it take a VirtIODevice and calling it
  from virtio_device_exit

- adding a k->exit callback

virtio_device_exit is still overwritten, the next patches will fix that.

Cc: qemu-stable@nongnu.org
Acked-by: Andreas Faerber <afaerber@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-12-09 21:46:48 +01:00
yinyin
1ae2757c6c virtio: virtqueue_get_avail_bytes: fix desc_pa when loop over the indirect descriptor table
virtqueue_get_avail_bytes: when found a indirect desc, we need loop over it.
           /* loop over the indirect descriptor table */
           indirect = 1;
           max = vring_desc_len(desc_pa, i) / sizeof(VRingDesc);
           num_bufs = i = 0;
           desc_pa = vring_desc_addr(desc_pa, i);
But, It init i to 0, then use i to update desc_pa. so we will always get:
desc_pa = vring_desc_addr(desc_pa, 0);
the last two line should swap.

Cc: qemu-stable@nongnu.org
Signed-off-by: Yin Yin <yin.yin@cs2c.com.cn>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-08-25 12:52:33 +03:00
Anthony Liguori
3ee1ee80d2 pci,virtio fixes for 1.6
This includes some last-minute bugfixes for 1.6.
 All very small patches that also look very safe to me.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'mst/tags/for_anthony' into staging

pci,virtio fixes for 1.6

This includes some last-minute bugfixes for 1.6.
All very small patches that also look very safe to me.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Mon 12 Aug 2013 04:28:57 AM CDT using RSA key ID D28D5469
# gpg: Can't check signature: public key not found

# By Michael S. Tsirkin (2) and others
# Via Michael S. Tsirkin
* mst/tags/for_anthony:
  vhost: clear signalled_used_valid on vhost stop
  virtio: clear signalled_used_valid when switching from dataplane
  i82801b11: Fix i82801b11 PCI host bridge config space
  pc: disable pci-info for 1.6

Message-id: 1376308831-19978-1-git-send-email-mst@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-08-12 08:32:55 -05:00
Stefan Hajnoczi
6793dfd1b6 virtio: clear signalled_used_valid when switching from dataplane
When the dataplane thread stops, its vring.c implementation synchronizes
vring state back to virtio.c so we can continue emulating the virtio
device.

This patch ensures that virtio.c's signalled_used_valid flag is reset so
that we do not suppress guest notifications due to stale signalled_used
values.

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-08-12 12:19:04 +03:00
Peter Maydell
f6049f4483 hw/virtio/virtio: Don't allow guests to add/remove queues
A queue size of 0 is used to indicate a nonexistent queue, so
don't allow the guest to flip a queue between zero-size and
non-zero-size. Don't permit setting of negative queue sizes
either.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1374853288-9912-2-git-send-email-peter.maydell@linaro.org
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
2013-08-09 16:50:23 +01:00
Peter Maydell
6ce69d1c77 virtio: Support transports which can specify the vring alignment
Support virtio transports which can specify the vring alignment
(ie where the guest communicates this to the host) by providing
a new virtio_queue_set_align() function. (The default alignment
remains as before.)

Transports which wish to make use of this must set the
has_variable_vring_alignment field in their VirtioBusClass
struct to true; they can then change the alignment via
virtio_queue_set_align().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1373977512-28932-5-git-send-email-peter.maydell@linaro.org
2013-07-19 12:58:46 +01:00
Peter Maydell
e63c0ba1bc virtio: Add support for guest setting of queue size
The MMIO virtio transport spec allows the guest to tell the host how
large the queue size is. Add virtio_queue_set_num() function which
implements this in the QEMU common virtio support code.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1373977512-28932-4-git-send-email-peter.maydell@linaro.org
2013-07-19 12:58:46 +01:00
Jason Wang
5f5a131865 virtio: properly validate address before accessing config
There are several several issues in the current checking:

- The check was based on the minus of unsigned values which can overflow
- It was done after .{set|get}_config() which can lead crash when config_len
  is zero since vdev->config is NULL

Fix this by:

- Validate the address in virtio_pci_config_{read|write}() before
  .{set|get}_config
- Use addition instead minus to do the validation

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Petr Matousek <pmatouse@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Petr Matousek <pmatouse@redhat.com>
Message-id: 1367905369-10765-1-git-send-email-jasowang@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-05-08 15:54:21 -05:00
KONRAD Frederic
1034e9cf4d virtio: add virtio_device_set_child_bus_name.
Add virtio_device_set_child_bus_name function.

It will be used with virtio-serial-x and virtio-scsi-x to set the
child bus name before calling virtio-x-device's init.

Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Message-id: 1367330931-12994-3-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-05-03 12:05:15 -05:00
KONRAD Frederic
6a1a8cc7af virtio: cleanup: init and exit function.
This clean the init and the exit functions and rename virtio_common_cleanup
to virtio_cleanup.

Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1366791683-5350-7-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-04-24 11:50:21 -05:00