For good reason, vhost-user is currently built asynchronously, that
way better performance can be obtained. However, for certain use
cases such as simulation, this is problematic.
Consider an event-based simulation in which both the device and CPU
have scheduled according to a simulation "calendar". Now, consider
the CPU sending I/O to the device, over a vring in the vhost-user
protocol. In this case, the CPU must wait for the vring interrupt
to have been processed by the device, so that the device is able to
put an entry onto the simulation calendar to obtain time to handle
the interrupt. Note that this doesn't mean the I/O is actually done
at this time, it just means that the handling of it is scheduled
before the CPU can continue running.
This cannot be done with the asynchronous eventfd based vring kick
and call design.
Extend the protocol slightly, so that a message can be used for kick
and call instead, if VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS is
negotiated. This in itself doesn't guarantee synchronisation, but both
sides can also negotiate VHOST_USER_PROTOCOL_F_REPLY_ACK and thus get
a reply to this message by setting the need_reply flag, and ensure
synchronisation this way.
To really use it in both directions, VHOST_USER_PROTOCOL_F_SLAVE_REQ
is also needed.
Since it is used for simulation purposes and too many messages on
the socket can lock up the virtual machine, document that this should
only be used together with the mentioned features.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Message-Id: <20200123081708.7817-6-johannes@sipsolutions.net>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The qemu-option-trace.rst.inc file contains a rST documentation
fragment which describes trace options common to qemu-nbd and
qemu-img. We put this file into interop/, but we'd like to move the
qemu-nbd and qemu-img files into the tools/ manual. We could move
the .rst.inc file along with them, but we're eventually going to want
to use it for the main QEMU binary options documentation too, and
that will be in system/. So move qemu-option-trace.rst.inc to the
top-level docs/ directory, where all these files can include it via
.. include:: ../qemu-option-trace.rst.inc
This does have the slight downside that we now need to explicitly
tell Make which manuals use this file rather than relying on
a wildcard for all .rst.inc in the manual.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20200217155415.30949-3-peter.maydell@linaro.org
In many cases the target of a convert operation is a newly provisioned
target that the user knows is blank (reads as zero). In this situation
there is no requirement for qemu-img to wastefully zero out the entire
device.
Add a new option, --target-is-zero, allowing the user to indicate that
an existing target device will return zeros for all reads.
Signed-off-by: David Edmondson <david.edmondson@oracle.com>
Message-Id: <20200205110248.2009589-2-david.edmondson@oracle.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
The patch adds a new additional field to the qcow2 header: compression_type,
which specifies compression type. If field is absent or zero, default
compression type is set: ZLIB, which corresponds to current behavior.
New compression type (ZSTD) is to be added in further commit.
Suggested-by: Denis Plotnikov <dplotnikov@virtuozzo.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200131142219.3264-3-vsementsov@virtuozzo.com>
[mreitz: s/Bits 3-63: Reserved/Bits 4-63: Reserved/]
Signed-off-by: Max Reitz <mreitz@redhat.com>
Make it more obvious how to add new fields to the version 3 header and
how to interpret them.
The specification is adjusted so that for new defined optional fields:
1. Software may support some of these optional fields and ignore the
others, which means that features may be backported to downstream
Qemu independently.
2. If we want to add incompatible field (or a field, for which some of
its values would be incompatible), it must be accompanied by
incompatible feature bit.
Also the concept of "default is zero" is clarified, as it's strange to
say that the value of the field is assumed to be zero for the software
version which don't know about the field at all and don't know how to
treat it be it zero or not.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200131142219.3264-2-vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
[mreitz: s/some its/some of its/]
Signed-off-by: Max Reitz <mreitz@redhat.com>
Document the virtiofsd(1) program and its command-line options. This
man page is a rST conversion of the original texi documentation that I
wrote.
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
The virtfs-proxy-helper documentation is currently in
fsdev/qemu-trace-stap.texi in Texinfo format, which we
present to the user as:
* a virtfs-proxy-helper manpage
* but not (unusually for QEMU) part of the HTML docs
Convert the documentation to rST format that lives in
the docs/ subdirectory, and present it to the user as:
* a virtfs-proxy-helper manpage
* part of the interop/ Sphinx manual
There are minor formatting changes to suit Sphinx, but no
content changes. In particular I've split the -u and -g
options into each having their own description text.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Greg Kurz <groug@kaod.org>
Message-id: 20200124162606.8787-9-peter.maydell@linaro.org
The qemu-trace-stap documentation is currently in
scripts/qemu-trace-stap.texi in Texinfo format, which we
present to the user as:
* a qemu-trace-stap manpage
* but not (unusually for QEMU) part of the HTML docs
Convert the documentation to rST format that lives in
the docs/ subdirectory, and present it to the user as:
* a qemu-trace-stap manpage
* part of the interop/ Sphinx manual
There are minor formatting changes to suit Sphinx, but no
content changes.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20200124162606.8787-8-peter.maydell@linaro.org
The qemu-img documentation is currently in qemu-nbd.texi in Texinfo
format, which we present to the user as:
* a qemu-img manpage
* a section of the main qemu-doc HTML documentation
Convert the documentation to rST format, and present it to the user as:
* a qemu-img manpage
* part of the interop/ Sphinx manual
The qemu-img rST document uses the new hxtool extension
to handle pulling rST fragments out of qemu-img-cmds.hx.
The documentation of the various options and commands is rather
muddled, with some options being described inside the relevant
command description and some in a more general section near the start
of the manual. All the command synopses are replicated in the .hx
file and then again in the manual. A lot of text is also duplicated
in the qemu-img.c code for the help text. I have not attempted to
deal with any of this, but have simply transposed the existing
structure into rST.
As usual, there are some minor formatting changes but no
textual changes, except that as with one or two other conversions
I have dropped the 'see also' section since it's not very
informative and looks odd in the HTML.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20200124162606.8787-6-peter.maydell@linaro.org
virtiofsd first pull v2
Import our virtiofsd.
This pulls in the daemon to drive a file system connected to the
existing qemu virtiofsd device.
It's derived from upstream libfuse with lots of changes (and a lot
trimmed out).
The daemon lives in the newly created qemu/tools/virtiofsd
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
v2
drop the docs while we discuss where they should live
and we need to redo the manpage in anything but texi
# gpg: Signature made Thu 23 Jan 2020 16:45:18 GMT
# gpg: using RSA key 45F5C71B4A0CB7FB977A9FA90516331EBC5BFDE7
# gpg: Good signature from "Dr. David Alan Gilbert (RH2) <dgilbert@redhat.com>" [full]
# Primary key fingerprint: 45F5 C71B 4A0C B7FB 977A 9FA9 0516 331E BC5B FDE7
* remotes/dgilbert-gitlab/tags/pull-virtiofs-20200123b: (108 commits)
virtiofsd: add some options to the help message
virtiofsd: stop all queue threads on exit in virtio_loop()
virtiofsd/passthrough_ll: Pass errno to fuse_reply_err()
virtiofsd: Convert lo_destroy to take the lo->mutex lock itself
virtiofsd: add --thread-pool-size=NUM option
virtiofsd: fix lo_destroy() resource leaks
virtiofsd: prevent FUSE_INIT/FUSE_DESTROY races
virtiofsd: process requests in a thread pool
virtiofsd: use fuse_buf_writev to replace fuse_buf_write for better performance
virtiofsd: add definition of fuse_buf_writev()
virtiofsd: passthrough_ll: Use cache_readdir for directory open
virtiofsd: Fix data corruption with O_APPEND write in writeback mode
virtiofsd: Reset O_DIRECT flag during file open
virtiofsd: convert more fprintf and perror to use fuse log infra
virtiofsd: do not always set FUSE_FLOCK_LOCKS
virtiofsd: introduce inode refcount to prevent use-after-free
virtiofsd: passthrough_ll: fix refcounting on remove/rename
libvhost-user: Fix some memtable remap cases
virtiofsd: rename inode->refcount to inode->nlookup
virtiofsd: prevent races with lo_dirp_put()
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Add the --print-capabilities option as per vhost-user.rst "Backend
programs conventions". Currently there are no advertised features.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
The qemu-nbd documentation is currently in qemu-nbd.texi in Texinfo
format, which we present to the user as:
* a qemu-nbd manpage
* a section of the main qemu-doc HTML documentation
Convert the documentation to rST format, and present it to the user as:
* a qemu-nbd manpage
* part of the interop/ Sphinx manual
This follows the same pattern as commit 27a296fce9 did for the
qemu-ga manpage.
All the content of the old manpage is retained, except that I have
dropped the "This is free software; see the source for copying
conditions. There is NO warranty..." text that was in the old AUTHOR
section; Sphinx's manpage builder doesn't expect that much text in
the AUTHOR section, and since none of our other manpages have it it
seems easiest to delete it rather than try to figure out where else
in the manpage to put it.
The only other textual change is that I have had to give the
--nocache option its own description ("Equivalent to --cache=none")
because Sphinx doesn't have an equivalent of using item/itemx
to share a description between two options.
Some minor aspects of the formatting have changed, to suit what is
easiest for Sphinx to output. (The most notable is that Sphinx
option section option syntax doesn't support '--option foo=bar'
with bar underlined rather than bold, so we have to switch to
'--option foo=BAR' instead.)
The contents of qemu-option-trace.texi are now duplicated in
docs/interop/qemu-option-trace.rst.inc, until such time as we complete
the conversion of the other files which use it; since it has had only
3 changes in 3 years, this shouldn't be too awkward a burden.
(We use .rst.inc because if this file fragment has a .rst extension
then Sphinx complains about not seeing it in a toctree.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200116141511.16849-2-peter.maydell@linaro.org
virtio, pci, pc: fixes, features
Bugfixes all over the place.
HMAT support.
New flags for vhost-user-blk utility.
Auto-tuning of seg max for virtio storage.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
# gpg: Signature made Mon 06 Jan 2020 17:05:05 GMT
# gpg: using RSA key 5D09FD0871C8F85B94CA8A0D281F0DB8D28D5469
# gpg: issuer "mst@redhat.com"
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
# gpg: aka "Michael S. Tsirkin <mst@redhat.com>" [full]
# 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: (32 commits)
intel_iommu: add present bit check for pasid table entries
intel_iommu: a fix to vtd_find_as_from_bus_num()
virtio-net: delete also control queue when TX/RX deleted
virtio: reset region cache when on queue deletion
virtio-mmio: update queue size on guest write
tests: add virtio-scsi and virtio-blk seg_max_adjust test
virtio: make seg_max virtqueue size dependent
hw: fix using 4.2 compat in 5.0 machine types for i440fx/q35
vhost-user-scsi: reset the device if supported
vhost-user: add VHOST_USER_RESET_DEVICE to reset devices
hw/pci/pci_host: Let pci_data_[read/write] use unsigned 'size' argument
hw/pci/pci_host: Remove redundant PCI_DPRINTF()
virtio-mmio: Clear v2 transport state on soft reset
ACPI: add expected files for HMAT tests (acpihmat)
tests/bios-tables-test: add test cases for ACPI HMAT
tests/numa: Add case for QMP build HMAT
hmat acpi: Build Memory Side Cache Information Structure(s)
hmat acpi: Build System Locality Latency and Bandwidth Information Structure(s)
hmat acpi: Build Memory Proximity Domain Attributes Structure(s)
numa: Extend CLI to provide memory side cache information
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
When instantiated, this object will connect to the given D-Bus bus
"addr". During migration, it will take/restore the data from
org.qemu.VMState1 instances. See documentation for details.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Add a VHOST_USER_RESET_DEVICE message which will reset the vhost user
backend. Disabling all rings, and resetting all internal state, ready
for the backend to be reinitialized.
A backend has to report it supports this features with the
VHOST_USER_PROTOCOL_F_RESET_DEVICE protocol feature bit. If it does
so, the new message is used instead of sending a RESET_OWNER which has
had inconsistent implementations.
Signed-off-by: David Vrabel <david.vrabel@nutanix.com>
Signed-off-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Message-Id: <1572385083-5254-2-git-send-email-raphael.norwitz@nutanix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The qemu-ga documentation is currently in qemu-ga.texi in
Texinfo format, which we present to the user as:
* a qemu-ga manpage
* a section of the main qemu-doc HTML documentation
Convert the documentation to rST format, and present it to
the user as:
* a qemu-ga manpage
* part of the interop/ Sphinx manual
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Tested-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Message-id: 20190905131040.8350-1-peter.maydell@linaro.org
