This patch prepares for the removal of unnecessary lockcnt inc/dec pairs.
Extract the dispatching loop for file descriptor handlers into a new
function aio_dispatch_handlers, and then inline aio_dispatch into
aio_poll.
aio_dispatch can now become void.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-17-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-16-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-15-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This covers both file descriptor callbacks and polling callbacks,
since they execute related code.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-14-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-13-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The AioContext data structures are now protected by list_lock and/or
they are walked with FOREACH_RCU primitives. There is no need anymore
to acquire the AioContext for the entire duration of aio_dispatch.
Instead, just acquire it before and after invoking the callbacks.
The next step is then to push it further down.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-12-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
qed_aio_start_io and qed_aio_next_io will not have to acquire/release
the AioContext, while qed_aio_next_io_cb will. Split the functionality
and gain a little type-safety in the process.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-11-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Keep the coroutine on the same AioContext. Without this change,
there would be a race between yielding the coroutine and reentering it.
While the race cannot happen now, because the code only runs from a single
AioContext, this will change with multiqueue support in the block layer.
While doing the change, replace custom bottom half with aio_co_schedule.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-10-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
As a small step towards the introduction of multiqueue, we want
coroutines to remain on the same AioContext that started them,
unless they are moved explicitly with e.g. aio_co_schedule. This patch
avoids that coroutines switch AioContext when they use a CoMutex.
For now it does not make much of a difference, because the CoMutex
is not thread-safe and the AioContext itself is used to protect the
CoMutex from concurrent access. However, this is going to change.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-9-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
In the client, read the reply headers from a coroutine, switching the
read side between the "read header" coroutine and the I/O coroutine that
reads the body of the reply.
In the server, if the server can read more requests it will create a new
"read request" coroutine as soon as a request has been read. Otherwise,
the new coroutine is created in nbd_request_put.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-8-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Support separate coroutines for reading and writing, and place the
read/write handlers on the AioContext that the QIOChannel is registered
with.
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213135235.12274-7-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This is in preparation for making qio_channel_yield work on
AioContexts other than the main one.
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213135235.12274-6-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Once the thread pool starts using aio_co_wake, it will also need
qemu_get_current_aio_context(). Make test-thread-pool create
an AioContext with qemu_init_main_loop, so that stubs/iothread.c
and tests/iothread.c can provide the rest.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213135235.12274-5-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
qcow2_create2 calls this. Do not run a nested event loop, as that
breaks when aio_co_wake tries to queue the coroutine on the co_queue_wakeup
list of the currently running one.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213135235.12274-4-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
aio_co_wake provides the infrastructure to start a coroutine on a "home"
AioContext. It will be used by CoMutex and CoQueue, so that coroutines
don't jump from one context to another when they go to sleep on a
mutex or waitqueue. However, it can also be used as a more efficient
alternative to one-shot bottom halves, and saves the effort of tracking
which AioContext a coroutine is running on.
aio_co_schedule is the part of aio_co_wake that starts a coroutine
on a remove AioContext, but it is also useful to implement e.g.
bdrv_set_aio_context callbacks.
The implementation of aio_co_schedule is based on a lock-free
multiple-producer, single-consumer queue. The multiple producers use
cmpxchg to add to a LIFO stack. The consumer (a per-AioContext bottom
half) grabs all items added so far, inverts the list to make it FIFO,
and goes through it one item at a time until it's empty. The data
structure was inspired by OSv, which uses it in the very code we'll
"port" to QEMU for the thread-safe CoMutex.
Most of the new code is really tests.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213135235.12274-3-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
AioContext is fairly self contained, the only dependency is QEMUTimer but
that in turn doesn't need anything else. So move them out of block-obj-y
to avoid introducing a dependency from io/ to block-obj-y.
main-loop and its dependency iohandler also need to be moved, because
later in this series io/ will call iohandler_get_aio_context.
[Changed copyright "the QEMU team" to "other QEMU contributors" as
suggested by Daniel Berrange and agreed by Paolo.
--Stefan]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213135235.12274-2-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Check message size too when figuring whenever we should expect more data.
Fix debug message to show useful data, p->iov.size is fixed anyway if we
land there, print how much we got meanwhile instead.
Also check announced message size against actual message size. That
is a more general fix for CVE-2017-5898 than commit "c7dfbf3 usb: ccid:
check ccid apdu length".
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 1487250819-23764-4-git-send-email-kraxel@redhat.com
Move up header size check, so we can use header fields in sanity checks
(in followup patches). Also reword the debug message.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 1487250819-23764-3-git-send-email-kraxel@redhat.com
Add err goto label where we can jump to from all error conditions.
STALL request on all errors. Reset position on all errors.
Normal request processing is not in a else branch any more, so this code
is reintended, there are no code changes in that part of the code
though.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 1487250819-23764-2-git-send-email-kraxel@redhat.com
Turn existing TYPE_XHCI into an abstract base class.
Create two child classes, TYPE_NEC_XHCI (same name as old xhci
controller) and TYPE_QEMU_XHCI (using an ID from our namespace).
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Message-id: 1486382139-30630-3-git-send-email-kraxel@redhat.com
The nec/renesas driver problems have finally been debugged and root
caused, see commit "7da76e1 xhci: fix event queue IRQ handling".
It's pretty clear now that
(a) The whole "driver can't handle ring full" story is most likely
wrong.
(b) The ER_FULL_HACK workaround based on the false assumtion doesn't
much. It avoids the driver crashing (without commit 7da76e1), but
it doesn't make usb work.
(c) With 7da76e1 applied it doesn't trigger any more.
So, lets kill it. Or, to be exact, lets almost kill it. Some data
fields are kept unused in the state struct, for live migration backward
compatibility.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 1486382139-30630-2-git-send-email-kraxel@redhat.com
Limits should be big enough that normal guest should not hit it.
Add a tracepoint to log them, just in case. Also, while being
at it, log the existing link trb limit too.
Reported-by: 李强 <liqiang6-s@360.cn>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 1486383669-6421-1-git-send-email-kraxel@redhat.com
The guest may builds an infinite loop with link eds. This patch
limit the number of linked ed to avoid this.
Signed-off-by: Li Qiang <liqiang6-s@360.cn>
Message-id: 5899a02e.45ca240a.6c373.93c1@mx.google.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
It should return 1 if an error occurs when reading iso td.
This will avoid an infinite loop issue in ohci_service_ed_list.
Signed-off-by: Li Qiang <liqiang6-s@360.cn>
Message-id: 5899ac3e.1033240a.944d5.9a2d@mx.google.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
In usb_ehci_init function, it initializes 's->ipacket', but there
is no corresponding function to free this. As the ehci can be hotplug
and unplug, this will leak host memory leak. In order to make the
hierarchy clean, we should add a ehci pci finalize function, then call
the clean function in ehci device.
Signed-off-by: Li Qiang <liqiang6-s@360.cn>
Message-id: 589a85b8.3c2b9d0a.b8e6.1434@mx.google.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Unfortunately some older versions of makeinfo don't correctly
handle the -D command line option and fail to set the variable.
This then causes them to complain
docs/qemu-ga-ref.texi:41: warning: undefined flag: VERSION
Work around this by doing as the autotools do, and writing
the information into a version.texi file which we then
include from the .texi files that need it.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1487357968-31000-1-git-send-email-peter.maydell@linaro.org>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
When we build qemu-qmp-ref.txt this causes texinfo to complain several
times:
"Negative repeat count does nothing at
/usr/share/texinfo/Texinfo/Convert/Line.pm line 124."
It also doesn't display correctly, because the "Notes" text disappears
entirely in the HTML version because it thinks there's no actual
quotation text.
The text file output formatting is also not good.
To solve those problems, remove usage of @quotation, and simply use bold
face for the section name.
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170217093416.27688-1-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
When multiple GPU are available, picking the first one isn't always the
best choice. Learn to specify a device rendernode.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20170212112118.16044-1-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Add QEMU Wacom Penpartner serial tablet emulation.
GSoC 2016 project.
Signed-off-by: Anatoli Huseu1 <avg.tolik@gmail.com>
Various cleanups.
Add line speed tracking.
Implement ST and SP commands.
Adapted to chardev QOMification.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 1486391007-10116-1-git-send-email-kraxel@redhat.com
Commit 8b0caab0 ("ps2: add support for mice with extra/side buttons")
accidentally swapped right and middle mouse buttons. This commit corrects
the mapping as expected by the ps2 controller.
Signed-off-by: Fabian Lesniak <fabian@lesniak-it.de>
Message-id: 20170204150319.8907-1-fabian@lesniak-it.de
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
virtio is using region caches for performance
iommu support for IOTLBs
misc 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
virtio, pci: fixes, features
virtio is using region caches for performance
iommu support for IOTLBs
misc fixes
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
# gpg: Signature made Fri 17 Feb 2017 19:53:02 GMT
# 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: (23 commits)
intel_iommu: vtd_slpt_level_shift check level
intel_iommu: convert dbg macros to trace for trans
intel_iommu: convert dbg macros to traces for inv
intel_iommu: renaming gpa to iova where proper
intel_iommu: simplify irq region translation
intel_iommu: add "caching-mode" option
vfio: allow to notify unmap for very large region
vfio: introduce vfio_get_vaddr()
vfio: trace map/unmap for notify as well
pcie: simplify pcie_add_capability()
virtio: Fix no interrupt when not creating msi controller
virtio: use VRingMemoryRegionCaches for avail and used rings
virtio: check for vring setup in virtio_queue_update_used_idx
virtio: use VRingMemoryRegionCaches for descriptor ring
virtio: add MemoryListener to cache ring translations
virtio: use MemoryRegionCache to access descriptors
exec: make address_space_cache_destroy idempotent
virtio: use address_space_map/unmap to access descriptors
virtio: add virtio_*_phys_cached
memory: make memory_listener_unregister idempotent
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
I did some work with real ColdFire boards in the past, and after
QOMifying most of the ColdFire devices recently, I feel confident
that I could at least take care of odd fixes for these boards.
Signed-off-by: Thomas Huth <huth@tuxfamily.org>
Use type_init() and friends to adapt the ColdFire interrupt
controller to the latest QEMU device conventions.
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Thomas Huth <huth@tuxfamily.org>
Since it is now possible to instantiate a CPU and RAM with the "none"
machine, too, and a kernel can be loaded there with the generic loader
device, there is no more need for the m68k "dummy" machine. Thus let's
remove this unmaintained file now.
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Thomas Huth <huth@tuxfamily.org>
This helps in debugging incorrect level passed in.
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Another patch to convert the DPRINTF() stuffs. This patch focuses on the
address translation path and caching.
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
VT-d codes are still using static DEBUG_INTEL_IOMMU macro. That's not
good, and we should end the day when we need to recompile the code
before getting useful debugging information for vt-d. Time to switch to
the trace system. This is the first patch to do it.
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
There are lots of places in current intel_iommu.c codes that named
"iova" as "gpa". It is really confusing to use a name "gpa" in these
places (which is very easily to be understood as "Guest Physical
Address", while it's not). To make the codes (much) easier to be read, I
decided to do this once and for all.
No functional change is made. Only literal ones.
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Now we have a standalone memory region for MSI, all the irq region
requests should be redirected there. Cleaning up the block with an
assertion instead.
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This capability asks the guest to invalidate cache before each map operation.
We can use this invalidation to trap map operations in the hypervisor.
Signed-off-by: Aviv Ben-David <bd.aviv@gmail.com>
[peterx: using "caching-mode" instead of "cache-mode" to align with spec]
[peterx: re-write the subject to make it short and clear]
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Aviv Ben-David <bd.aviv@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Linux vfio driver supports to do VFIO_IOMMU_UNMAP_DMA for a very big
region. This can be leveraged by QEMU IOMMU implementation to cleanup
existing page mappings for an entire iova address space (by notifying
with an IOTLB with extremely huge addr_mask). However current
vfio_iommu_map_notify() does not allow that. It make sure that all the
translated address in IOTLB is falling into RAM range.
The check makes sense, but it should only be a sensible checker for
mapping operations, and mean little for unmap operations.
This patch moves this check into map logic only, so that we'll get
faster unmap handling (no need to translate again), and also we can then
better support unmapping a very big region when it covers non-ram ranges
or even not-existing ranges.
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
A cleanup for vfio_iommu_map_notify(). Now we will fetch vaddr even if
the operation is unmap, but it won't hurt much.
One thing to mention is that we need the RCU read lock to protect the
whole translation and map/unmap procedure.
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>