Commit Graph

91 Commits

Author SHA1 Message Date
Peter Maydell
a08b4a9fe6 docs: Move tools documentation to tools manual
Move the following tools documentation files to the new tools manual:

 docs/interop/qemu-img.rst
 docs/interop/qemu-nbd.rst
 docs/interop/virtfs-proxy-helper.rst
 docs/interop/qemu-trace-stap.rst
 docs/interop/virtiofsd.rst

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: 20200217155415.30949-4-peter.maydell@linaro.org
2020-02-25 10:48:06 +00:00
Peter Maydell
bb43ee6c4f docs: Move qemu-option-trace.rst.inc to docs/
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
2020-02-25 10:48:05 +00:00
David Edmondson
168468fe19 qemu-img: Add --target-is-zero to convert
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>
2020-02-20 16:43:42 +01:00
Vladimir Sementsov-Ogievskiy
66fcbca5a7 docs: qcow2: introduce compression type feature
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>
2020-02-20 16:42:52 +01:00
Vladimir Sementsov-Ogievskiy
3ae3fcfae5 docs: improve qcow2 spec about extending image header
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>
2020-02-20 16:20:14 +01:00
Stefan Hajnoczi
6a7e2bbee5 docs: add virtiofsd(1) man page
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>
2020-02-10 17:25:52 +00:00
Peter Maydell
5b7686f3fa nbd patches for 2020-02-06
- Allow setting NBD description from QMP for parity with qemu-nbd
 - Remove deprecated 'qemu-nbd --partition'
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Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2020-02-06' into staging

nbd patches for 2020-02-06

- Allow setting NBD description from QMP for parity with qemu-nbd
- Remove deprecated 'qemu-nbd --partition'

# gpg: Signature made Thu 06 Feb 2020 12:50:46 GMT
# gpg:                using RSA key 71C2CC22B1C4602927D2F3AAA7A16B4A2527436A
# gpg: Good signature from "Eric Blake <eblake@redhat.com>" [full]
# gpg:                 aka "Eric Blake (Free Software Programmer) <ebb9@byu.net>" [full]
# gpg:                 aka "[jpeg image of size 6874]" [full]
# Primary key fingerprint: 71C2 CC22 B1C4 6029 27D2  F3AA A7A1 6B4A 2527 436A

* remotes/ericb/tags/pull-nbd-2020-02-06:
  qemu-nbd: Removed deprecated --partition option
  docs: Fix typo in qemu-nbd -P replacement
  nbd: Allow description when creating NBD blockdev

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-02-06 18:59:12 +00:00
Julia Suvorova
890fb1f6b3 qemu-img: Place the '-i aio' option in alphabetical order
The '-i AIO' option was accidentally placed after '-n' and '-t'. Move it
after '--flush-interval'.

Signed-off-by: Julia Suvorova <jusual@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200205163008.204493-1-jusual@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2020-02-06 11:09:36 +01:00
Eric Blake
0bc16997f5 qemu-nbd: Removed deprecated --partition option
The option was deprecated in 4.0.0 (commit 0ae2d546); it's now been
long enough with no complaints to follow through with that process.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200123164650.1741798-3-eblake@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-02-05 17:29:49 -06:00
Peter Maydell
78813586b0 virtfs-proxy-helper: Convert documentation to rST
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
2020-02-03 11:02:23 +00:00
Peter Maydell
605ffebb2e scripts/qemu-trace-stap: Convert documentation to rST
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
2020-02-03 11:02:23 +00:00
Peter Maydell
e13c59fa44 qemu-img: Convert invocation documentation to rST
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
2020-02-03 11:02:22 +00:00
Thomas Huth
b2ce76a073 hw/ppc/prep: Remove the deprecated "prep" machine and the OpenHackware BIOS
It's been deprecated since QEMU v3.1. The 40p machine should be
used nowadays instead.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20200114114617.28854-1-thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-02-02 14:07:57 +11:00
Aarushi Mehta
7680274da1 qemu-nbd: adds option for aio engines
Signed-off-by: Aarushi Mehta <mehta.aaru20@gmail.com>
Acked-by: Eric Blake <eblake@redhat.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200120141858.587874-14-stefanha@redhat.com
Message-Id: <20200120141858.587874-14-stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-01-30 21:01:38 +00:00
Peter Maydell
a43efa34c7 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
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Merge remote-tracking branch 'remotes/dgilbert-gitlab/tags/pull-virtiofs-20200123b' into staging

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>
2020-01-24 09:59:11 +00:00
Stefan Hajnoczi
45018fbb0a virtiofsd: add --print-capabilities option
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>
2020-01-23 16:41:36 +00:00
Peter Maydell
87c0868f46 qemu-nbd: Convert invocation documentation to rST
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
2020-01-23 15:22:39 +00:00
Peter Maydell
973d306dd6 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>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

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>
2020-01-07 16:25:00 +00:00
Marc-André Lureau
5010cec2bc Add dbus-vmstate object
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>
2020-01-06 18:41:32 +04:00
Marc-André Lureau
a566907f1b docs: start a document to describe D-Bus usage
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-06 18:41:32 +04:00
Raphael Norwitz
d91d57e604 vhost-user: add VHOST_USER_RESET_DEVICE to reset devices
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>
2020-01-05 07:03:03 -05:00
Micky Yun Chan
6620801f39 Implement backend program convention command for vhost-user-blk
This patch is to add standard commands defined in docs/interop/vhost-user.rst
For vhost-user-* program

Signed-off-by: Micky Yun Chan (michiboo) <chanmickyyun@gmail.com>
Message-Id: <20191209015331.5455-1-chanmickyyun@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-01-05 07:03:03 -05:00
Dr. David Alan Gilbert
df59feb197 global: Squash 'the the'
'the' has a tendency to double up; squash them back down.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20191104185202.102504-1-dgilbert@redhat.com>
[lv: removed disas/libvixl/vixl/invalset.h change]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2019-11-06 17:19:40 +01:00
Peter Maydell
27a296fce9 qemu-ga: Convert invocation documentation to rST
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
2019-09-13 16:05:01 +01:00
Eric Blake
0a4795455c nbd: Prepare for NBD_CMD_FLAG_FAST_ZERO
Commit fe0480d6 and friends added BDRV_REQ_NO_FALLBACK as a way to
avoid wasting time on a preliminary write-zero request that will later
be rewritten by actual data, if it is known that the write-zero
request will use a slow fallback; but in doing so, could not optimize
for NBD.  The NBD specification is now considering an extension that
will allow passing on those semantics; this patch updates the new
protocol bits and 'qemu-nbd --list' output to recognize the bit, as
well as the new errno value possible when using the new flag; while
upcoming patches will improve the client to use the feature when
present, and the server to advertise support for it.

The NBD spec recommends (but not requires) that ENOTSUP be avoided for
all but failures of a fast zero (the only time it is mandatory to
avoid an ENOTSUP failure is when fast zero is supported but not
requested during write zeroes; the questionable use is for ENOTSUP to
other actions like a normal write request).  However, clients that get
an unexpected ENOTSUP will either already be treating it the same as
EINVAL, or may appreciate the extra bit of information.  We were
equally loose for returning EOVERFLOW in more situations than
recommended by the spec, so if it turns out to be a problem in
practice, a later patch can tighten handling for both error codes.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20190823143726.27062-3-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
[eblake: tweak commit message, also handle EOPNOTSUPP]
2019-09-05 16:03:13 -05:00
Eric Blake
61cc872456 nbd: Advertise multi-conn for shared read-only connections
The NBD specification defines NBD_FLAG_CAN_MULTI_CONN, which can be
advertised when the server promises cache consistency between
simultaneous clients (basically, rules that determine what FUA and
flush from one client are able to guarantee for reads from another
client).  When we don't permit simultaneous clients (such as qemu-nbd
without -e), the bit makes no sense; and for writable images, we
probably have a lot more work before we can declare that actions from
one client are cache-consistent with actions from another.  But for
read-only images, where flush isn't changing any data, we might as
well advertise multi-conn support.  What's more, advertisement of the
bit makes it easier for clients to determine if 'qemu-nbd -e' was in
use, where a second connection will succeed rather than hang until the
first client goes away.

This patch affects qemu as server in advertising the bit.  We may want
to consider patches to qemu as client to attempt parallel connections
for higher throughput by spreading the load over those connections
when a server advertises multi-conn, but for now sticking to one
connection per nbd:// BDS is okay.

See also: https://bugzilla.redhat.com/1708300
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20190815185024.7010-1-eblake@redhat.com>
[eblake: tweak blockdev-nbd.c to not request shared when writable,
fix iotest 233]
Reviewed-by: John Snow <jsnow@redhat.com>
2019-09-05 15:51:55 -05:00
Markus Armbruster
ffaee83bcb qapi: Move query-target from misc.json to machine.json
Move query-target and its return type TargetInfo from misc.json to
machine.json, where they are covered by MAINTAINERS section "Machine
core".  Also move its implementation from arch_init.c to
hw/core/machine-qmp-cmds, where it is likewise covered.

All users of SysEmuTarget are now in machine.json.  Move it there from
common.json.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190709152053.16670-3-armbru@redhat.com>
2019-08-21 13:24:01 +02:00
Stefan Hajnoczi
df98d7ccc2 docs: clarify multiqueue vs multiple virtqueues
The vhost-user specification does not explain when
VHOST_USER_PROTOCOL_F_MQ must be implemented.  This may lead
implementors of vhost-user masters to believe that this protocol feature
is required for any device that has multiple virtqueues.  That would be
a mistake since existing vhost-user slaves offer multiple virtqueues but
do not advertise VHOST_USER_PROTOCOL_F_MQ.

For example, a vhost-net device with one rx/tx queue pair is not
multiqueue.  The slave does not need to advertise
VHOST_USER_PROTOCOL_F_MQ.  Therefore the master must assume it has these
virtqueues and cannot rely on askingt the slave how many virtqueues
exist.

Extend the specification to explain the different between true
multiqueue and regular devices with a fixed virtqueue layout.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20190624091304.666-1-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2019-07-25 04:17:34 -04:00
John Snow
a7786bfb0e docs/bitmaps: use QMP lexer instead of json
The annotated style json we use in QMP documentation is not strict json
and depending on the version of Sphinx (2.0+) or Pygments installed,
might cause the build to fail.

Use the new QMP lexer.

Further, some versions of Sphinx can not apply custom lexers to "code"
directives and require the use of "code-block" directives instead, so
make that change at this time as well.

Tested under:
- Sphinx 1.3.6 and Pygments 2.4
- Sphinx 1.7.6 and Pygments 2.2 (Fedora 29 packages)
- Sphinx 2.0.1 and Pygments 2.4
- Sphinx 3.0.0+/f396b3a783 and Pygments 2.4 (From Sphinx git c4f44bdd)

Reported-by: Aarushi Mehta <mehta.aaru20@gmail.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-id: 20190603214653.29369-4-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-07-10 15:08:07 -04:00
John Snow
575e622628 docs/interop/bitmaps.rst: Fix typos
Pygments and Sphinx get pickier all the time; Sphinx 2.1+ now catches
these errors.

Signed-off-by: John Snow <jsnow@redhat.com>
Reported-by: Aarushi Mehta <mehta.aaru20@gmail.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190603214653.29369-2-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-07-10 15:08:06 -04:00
Stefan Hajnoczi
3ef4dff2b3 docs: avoid vhost-user-net specifics in multiqueue section
The "Multiple queue support" section makes references to vhost-user-net
"queue pairs".  This is confusing for two reasons:
1. This actually applies to all device types, not just vhost-user-net.
2. VHOST_USER_GET_QUEUE_NUM returns the number of virtqueues, not the
   number of queue pairs.

Reword the section so that the vhost-user-net specific part is relegated
to the very end: we acknowledge that vhost-user-net historically
automatically enabled the first queue pair.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190626074815.19994-5-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-04 17:00:32 -04:00
Marc-André Lureau
00ab8cb141 docs/vhost-user.json: some firmware.json copy leftovers
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190605131221.29432-1-marcandre.lureau@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>
2019-06-16 16:16:52 -04:00
Marc-André Lureau
bd2e44fee4 vhost-user: add vhost_user_gpu_set_socket()
Add a new vhost-user message to give a unix socket to a vhost-user
backend for GPU display updates.

Back when I started that work, I added a new GPU channel because the
vhost-user protocol wasn't bidirectional. Since then, there is a
vhost-user-slave channel for the slave to send requests to the master.
We could extend it with GPU messages. However, the GPU protocol is
quite orthogonal to vhost-user, thus I chose to have a new dedicated
channel.

See vhost-user-gpu.rst for the protocol details.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20190524130946.31736-2-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-05-29 06:29:07 +02:00
Marc-André Lureau
ed1be66bfc docs: reST-ify vhost-user documentation
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190315180735.13096-1-marcandre.lureau@redhat.com>
Reviewed-by: Jens Freimann <jfreimann@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-05-20 18:40:02 -04:00
Peter Maydell
8482ff2eb3 Pull request
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Merge remote-tracking branch 'remotes/jnsnow/tags/bitmaps-pull-request' into staging

Pull request

# gpg: Signature made Wed 01 May 2019 21:24:16 BST
# gpg:                using RSA key F9B7ABDBBCACDF95BE76CBD07DEF8106AAFC390E
# gpg: Good signature from "John Snow (John Huston) <jsnow@redhat.com>" [full]
# Primary key fingerprint: FAEB 9711 A12C F475 812F  18F2 88A9 064D 1835 61EB
#      Subkey fingerprint: F9B7 ABDB BCAC DF95 BE76  CBD0 7DEF 8106 AAFC 390E

* remotes/jnsnow/tags/bitmaps-pull-request:
  docs/interop/bitmaps: rewrite and modernize doc
  Makefile: add nit-picky mode to sphinx-build

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-05-02 12:04:51 +01:00
John Snow
90edef80a0 docs/interop/bitmaps: rewrite and modernize doc
This just about rewrites the entirety of the bitmaps.rst document to
make it consistent with the 4.0 release. I have added new features seen
in the 4.0 release, as well as tried to clarify some points that keep
coming up when discussing this feature both in-house and upstream.

It does not yet cover pull backups or migration details, but I intend to
keep extending this document to cover those cases.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190426221528.30293-3-jsnow@redhat.com
[Adjusted commit message. --js]
Signed-off-by: John Snow <jsnow@redhat.com>
2019-05-01 16:21:24 -04:00
Peter Maydell
3b5b6e9b51 pci, pc, virtio: features, fixes, cleanups
intel-iommu scalable option
 pcie acs emulation
 beginning for vhost-user-blk reconnect and of vhost-user backend work
 misc fixes and cleanups
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

pci, pc, virtio: features, fixes, cleanups

intel-iommu scalable option
pcie acs emulation
beginning for vhost-user-blk reconnect and of vhost-user backend work
misc fixes and cleanups

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

# gpg: Signature made Wed 13 Mar 2019 02:52:02 GMT
# gpg:                using RSA key 281F0DB8D28D5469
# 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: (26 commits)
  i386, acpi: check acpi_memory_hotplug capacity in pre_plug
  gen_pcie_root_port: Add ACS (Access Control Services) capability
  pcie: Add a simple PCIe ACS (Access Control Services) helper function
  vhost-user-blk: Add support to get/set inflight buffer
  libvhost-user: Support tracking inflight I/O in shared memory
  libvhost-user: Introduce vu_queue_map_desc()
  libvhost-user: Remove unnecessary FD flag check for event file descriptors
  vhost-user: Support transferring inflight buffer between qemu and backend
  nvdimm: use NVDIMM_ACPI_IO_LEN for the proper IO size
  nvdimm: use *function* directly instead of allocating it again
  nvdimm: fix typo in nvdimm_build_nvdimm_devices argument
  intel_iommu: add scalable-mode option to make scalable mode work
  intel_iommu: add 256 bits qi_desc support
  intel_iommu: scalable mode emulation
  libvhost-user: add vu_queue_unpop()
  libvhost-user-glib: export vug_source_new()
  vhost-user: split vhost_user_read()
  vhost-user: wrap some read/write with retry handling
  libvhost-user: exit by default on VHOST_USER_NONE
  vhost-user: simplify vhost_user_init/vhost_user_cleanup
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-03-13 19:10:40 +00:00
Xie Yongji
5ad204bf2a vhost-user: Support transferring inflight buffer between qemu and backend
This patch introduces two new messages VHOST_USER_GET_INFLIGHT_FD
and VHOST_USER_SET_INFLIGHT_FD to support transferring a shared
buffer between qemu and backend.

Firstly, qemu uses VHOST_USER_GET_INFLIGHT_FD to get the
shared buffer from backend. Then qemu should send it back
through VHOST_USER_SET_INFLIGHT_FD each time we start vhost-user.

This shared buffer is used to track inflight I/O by backend.
Qemu should retrieve a new one when vm reset.

Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Signed-off-by: Chai Wen <chaiwen@baidu.com>
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Message-Id: <20190228085355.9614-2-xieyongji@baidu.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>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-12 22:31:21 -04:00
Marc-André Lureau
482580a658 vhost-user: define conventions for vhost-user backends
As discussed during "[PATCH v4 00/29] vhost-user for input & GPU"
review, let's define a common set of backend conventions to help with
management layer implementation, and interoperability.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20190308140454.32437-3-marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-12 21:22:31 -04:00
Vladimir Sementsov-Ogievskiy
2fd490c614 docs/interop/qcow2: Improve bitmap flag in_use specification
We already use (we didn't notice it) IN_USE flag for marking bitmap
metadata outdated, such as AUTO flag, which mirrors enabled/disabled
bitmaps. Now we are going to support bitmap resize, so it's good to
write IN_USE meaning with more details.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190311185147.52309-2-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-03-12 12:06:11 -04:00
Markus Armbruster
e33763be7c docs/interop/firmware.json: Prefer -machine to if=pflash
The previous commit added a way to configure firmware with -blockdev
rather than -drive if=pflash.  Document it as the preferred way.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190308131445.17502-13-armbru@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2019-03-11 22:54:25 +01:00
Kevin Wolf
e88153ea9a qcow2 spec: Describe string header extensions
Be more specific about the string representation in header extensions.

Suggested-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-03-08 12:26:46 +01:00
Kevin Wolf
65a3d073e9 qcow2: Extend spec for external data files
This adds external data file to the qcow2 spec as a new incompatible
feature.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-03-08 12:26:45 +01:00
Peter Maydell
f8cf7147f1 docs: Provide separate conf.py for each manual we want
By default Sphinx wants to build a single manual at once.
For QEMU, this doesn't suit us, because we want to have
separate manuals for "Developer's Guide", "User Manual",
and so on, and we don't want to ship the Developer's Guide
to end-users. However, we don't want to completely duplicate
conf.py for each manual, and we'd like to continue to
support "build all docs in one run" for third-party sites
like readthedocs.org.

Make the top-level conf.py support two usage forms:
 (1) as a common config file which is included by the conf.py
 for each of QEMU's manuals: in this case sphinx-build is run
 multiple times, once per subdirectory.
 (2) as a top level conf file which will result in building all
 the manuals into a single document: in this case sphinx-build is
 run once, on the top-level docs directory.

Provide per-manual conf.py files and top level pages for
our first two manuals:
 * QEMU Developer's Guide (docs/devel)
 * QEMU System Emulation Management and Interoperability Guide
   (docs/interop)

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Message-id: 20190305172139.32662-9-peter.maydell@linaro.org
Message-id: 20190228145624.24885-9-peter.maydell@linaro.org
2019-03-07 14:26:46 +00:00
Eric Blake
ba2d3b3ab2 nbd: Document timeline of various features
It can be useful to figure out which NBD protocol features are
exposed by a server, as well as what features a client will
take advantage of if available, for a given qemu release.  It's
not always precise to base features on version numbers (thanks
to downstream backports), but any documentation is better than
making users search through git logs themselves.

This patch originally stemmed from a request to document that
pristine 3.0 has a known bug where NBD_OPT_LIST_META_CONTEXT
with 0 queries forgot to advertise an available
"qemu:dirty-bitmap" context, but documenting bugs like this (or
the fact that 3.0 also botched NBD_CMD_CACHE) gets to be too
much details, especially since buggy releases will be less
likely connection targets over time.  Instead, I chose to just
remind users to check stable release branches.

Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20181215135324.152629-3-eblake@redhat.com>
Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
2019-01-04 17:41:28 -06:00
Eric Blake
aee03bf367 docs: Update references to JSON RFC
RFC8259 obsoletes RFC7159. Fix a couple of URLs to point to the
newer version.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20181203175702.128701-1-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-12-13 19:10:06 +01:00
Peter Xu
9ab84470ff monitor: Suspend monitor instead dropping commands
When a QMP client sends in-band commands more quickly that we can
process them, we can either queue them without limit (QUEUE), drop
commands when the queue is full (DROP), or suspend receiving commands
when the queue is full (SUSPEND).  None of them is ideal:

* QUEUE lets a misbehaving client make QEMU eat memory without bounds.
Not such a hot idea.

* With DROP, the client has to cope with dropped in-band commands.  To
inform the client, we send a COMMAND_DROPPED event then.  The event is
flawed by design in two ways: it's ambiguous (see commit d621cfe0a1),
and it brings back the "eat memory without bounds" problem.

* With SUSPEND, the client has to manage the flow of in-band commands to
keep the monitor available for out-of-band commands.

We currently DROP.  Switch to SUSPEND.

Managing the flow of in-band commands to keep the monitor available for
out-of-band commands isn't really hard: just count the number of
"outstanding" in-band commands (commands sent minus replies received),
and if it exceeds the limit, hold back additional ones until it drops
below the limit again.

Note that we need to be careful pairing the suspend with a resume, or
else the monitor will hang, possibly forever.  And here since we need to
make sure both:

     (1) popping request from the req queue, and
     (2) reading length of the req queue

will be in the same critical section, we let the pop function take the
corresponding queue lock when there is a request, then we release the
lock from the caller.

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20181009062718.1914-2-peterx@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-12-12 09:55:57 +01:00
Eric Blake
d3e1a7eb4c qcow2: Document some maximum size constraints
Although off_t permits up to 63 bits (8EB) of file offsets, in
practice, we're going to hit other limits first.  Document some
of those limits in the qcow2 spec (some are inherent, others are
implementation choices of qemu), and how choice of cluster size
can influence some of the limits.

While we cannot map any uncompressed virtual cluster to any
address higher than 64 PB (56 bits) (due to the current L1/L2
field encoding stopping at bit 55), qemu's cap of 8M for the
refcount table can still access larger host addresses for some
combinations of large clusters and small refcount_order.  For
comparison, ext4 with 4k blocks caps files at 16PB.

Another interesting limit: for compressed clusters, the L2 layout
requires an ever-smaller maximum host offset as cluster size gets
larger, down to a 512 TB maximum with 2M clusters.  In particular,
note that with a cluster size of 8k or smaller, the L2 entry for
a compressed cluster could technically point beyond the 64PB mark,
but when you consider that with 8k clusters and refcount_order = 0,
you cannot access beyond 512T without exceeding qemu's limit of an
8M cap on the refcount table, it is unlikely that any image in the
wild has attempted to do so.  To be safe, let's document that bits
beyond 55 in a compressed cluster must be 0.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-11-19 12:51:40 +01:00
Stefan Weil
963e64a486 docs: Fix some typos (most found by codespell)
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2018-09-25 17:26:18 +02:00
Thomas Huth
2feac451d2 Remove the deprecated -nodefconfig option
It's the same as -no-user-config and marked as deprecated since three
releases already. Time to remove it now.

Acked-by: Peter Krempa <pkrempa@redhat.com>
Acked-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2018-08-31 09:52:46 +02:00