Commit Graph

193 Commits

Author SHA1 Message Date
Philippe Mathieu-Daudé
5135fe7110 docs: Spell QEMU all caps
Replace Qemu -> QEMU.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20211118143401.4101497-1-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-19 10:16:58 +01:00
Vladimir Sementsov-Ogievskiy
1084159b31 qapi: deprecate drive-backup
Modern way is using blockdev-add + blockdev-backup, which provides a
lot more control on how target is opened.

As example of drive-backup problems consider the following:

User of drive-backup expects that target will be opened in the same
cache and aio mode as source. Corresponding logic is in
drive_backup_prepare(), where we take bs->open_flags of source.

It works rather bad if source was added by blockdev-add. Assume source
is qcow2 image. On blockdev-add we should specify aio and cache options
for file child of qcow2 node. What happens next:

drive_backup_prepare() looks at bs->open_flags of qcow2 source node.
But there no BDRV_O_NOCAHE neither BDRV_O_NATIVE_AIO: BDRV_O_NOCAHE is
places in bs->file->bs->open_flags, and BDRV_O_NATIVE_AIO is nowhere,
as file-posix parse options and simply set s->use_linux_aio.

The documentation is updated in a minimal way, so that drive-backup is
noted only as a deprecated command, and blockdev-backup used in most of
places.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2021-11-09 18:21:19 +01:00
Vladimir Sementsov-Ogievskiy
24d6cc1fa1 docs/interop/bitmaps: use blockdev-backup
We are going to deprecate drive-backup, so use modern interface here.
In examples where target image creation is shown, show blockdev-add as
well. If target creation omitted, omit blockdev-add as well.

Reviewed-by: Kashyap Chamarthy <kchamart@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
2021-11-09 18:20:47 +01:00
John Snow
450e0f28a4 docs: remove non-reference uses of single backticks
The single backtick markup in ReST is the "default role". Currently,
Sphinx's default role is called "content". Sphinx suggests you can use
the "Any" role instead to turn any single-backtick enclosed item into a
cross-reference.

This is useful for things like autodoc for Python docstrings, where it's
often nicer to reference other types with `foo` instead of the more
laborious :py:meth:`foo`. It's also useful in multi-domain cases to
easily reference definitions from other Sphinx domains, such as
referencing C code definitions from outside of kerneldoc comments.

Before we do that, though, we'll need to turn all existing usages of the
"content" role to inline verbatim markup wherever it does not correctly
resolve into a cross-refernece by using double backticks instead.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <20211004215238.1523082-2-jsnow@redhat.com>
2021-11-08 12:27:23 +04:00
Paolo Bonzini
06905f6402 docs: standardize directory index to --- with overline
Use a standard heading format for the index.rst file in a directory.
Using overlines makes it clear that individual documents can use e.g.
=== for chapter titles and --- for section titles, as suggested in the
Linux kernel guidelines[1].  They could do it anyway, because documents
included in a toctree are parsed separately and therefore are not tied
to the same conventions for headings.  However, keeping some consistency is
useful since sometimes files are included from multiple places.

[1] https://www.kernel.org/doc/html/latest/doc-guide/sphinx.html

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-13 13:56:26 +02:00
Peter Maydell
6cb02f1522 docs: Move the protocol part of barrier.txt into interop
Most of docs/barrier.txt is describing the protocol implemented
by the input-barrier device. Move this into the interop
section of the manual, and rstify it.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-id: 20210727204112.12579-2-peter.maydell@linaro.org
2021-08-02 12:55:51 +01:00
Peter Maydell
6df743dc31 docs: Format literals correctly
In rST markup, single backticks `like this` represent "interpreted
text", which can be handled as a bunch of different things if tagged
with a specific "role":
https://docutils.sourceforge.io/docs/ref/rst/restructuredtext.html#interpreted-text
(the most common one for us is "reference to a URL, which gets
hyperlinked").

The default "role" if none is specified is "title_reference",
intended for references to book or article titles, and it renders
into the HTML as <cite>...</cite> (usually comes out as italics).

This commit fixes various places in the manual which were
using single backticks when double backticks (for literal text)
were intended, and covers those files where only one or two
instances of these errors were made.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2021-08-02 11:42:38 +01:00
Peter Maydell
4e0b15c252 docs: Move licence/copyright from HTML output to rST comments
Our built HTML documentation now has a standard footer which
gives the license for QEMU (and its documentation as a whole).
In almost all pages, we either don't bother to state the
copyright/license for the individual rST sources, or we put
it in an rST comment. There are just three pages which render
copyright or license information into the user-visible HTML.

Quoting a specific (different) license for an individual HTML
page within the manual is confusing. Downgrade the license
and copyright info to a comment within the rST source, bringing
these pages in line with the rest of our documents.

Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Message-id: 20210722192016.24915-3-peter.maydell@linaro.org
2021-08-02 11:42:38 +01:00
Peter Maydell
199a436305 docs: Remove stale TODO comments about license and version
Since commits 13f934e79f and 3a50c8f306, our HTML docs include a
footer to all pages stating the license and version.  We can
therefore delete the TODO comments suggesting we should do that from
our .rst files.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20210722192016.24915-2-peter.maydell@linaro.org
2021-08-02 11:42:38 +01:00
Alex Bennée
15d9c3cef1 docs: add a section on the generalities of vhost-user
While we do mention some of this stuff in the various daemons and
manuals the subtleties of the socket and memory sharing are sometimes
missed. This document attempts to give some background on vhost-user
daemons in general terms.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20210720232703.10650-4-alex.bennee@linaro.org>
2021-07-23 17:22:16 +01:00
Peter Maydell
21b6c26d63 docs: Remove "Contents:" lines from top-level subsections
Since the top-level subsections aren't self-contained manuals
any more, the "Contents:" lines at the top of each of their
index pages look a bit odd; remove them.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20210705095547.15790-4-peter.maydell@linaro.org
2021-07-18 10:59:46 +01:00
Peter Maydell
b4634487c4 docs: Stop calling the top level subsections of our manual 'manuals'
We merged our previous multiple-manual setup into a single Sphinx
manual, but we left some text in the various index.rst lines that
still calls the top level subsections separate 'manuals'.  Update
them to talk about "this section of the manual" instead, and remove
now-obsolete comments about how the index.rst files are the "top
level page for the 'foo' manual".

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20210705095547.15790-3-peter.maydell@linaro.org
2021-07-18 10:59:46 +01:00
Peter Maydell
d0ac9a6147 * Documentation updates
* Remove leading underscores from header guards
 * Display hexadecimal value with '0x' prefix
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Merge remote-tracking branch 'remotes/thuth-gitlab/tags/pull-request-2021-06-21' into staging

* Documentation updates
* Remove leading underscores from header guards
* Display hexadecimal value with '0x' prefix

# gpg: Signature made Mon 21 Jun 2021 11:33:53 BST
# gpg:                using RSA key 27B88847EEE0250118F3EAB92ED9D774FE702DB5
# gpg:                issuer "thuth@redhat.com"
# gpg: Good signature from "Thomas Huth <th.huth@gmx.de>" [full]
# gpg:                 aka "Thomas Huth <thuth@redhat.com>" [full]
# gpg:                 aka "Thomas Huth <huth@tuxfamily.org>" [full]
# gpg:                 aka "Thomas Huth <th.huth@posteo.de>" [unknown]
# Primary key fingerprint: 27B8 8847 EEE0 2501 18F3  EAB9 2ED9 D774 FE70 2DB5

* remotes/thuth-gitlab/tags/pull-request-2021-06-21:
  MAINTAINERS: Add qtest/arm-cpu-features.c to ARM TCG CPUs section
  fuzz: Display hexadecimal value with '0x' prefix
  Remove leading underscores from QEMU defines
  Update documentation to refer to new location for issues
  docs/tools/virtiofsd: Fix bad rst syntax
  docs/tools/virtiofsd.rst: Do not hard-code the QEMU binary name
  docs/interop/live-block-operations: Do not hard-code the QEMU binary name

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-06-24 09:31:26 +01:00
Thomas Huth
2c1730f780 docs/interop/live-block-operations: Do not hard-code the QEMU binary name
In downstream, we want to use a different name for the QEMU binary,
and some people might also use the docs for non-x86 binaries, that's
why we already created the |qemu_system| placeholder in the past.
Use it now in the live-block-operations doc, too.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210607172311.915385-1-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-06-21 05:43:11 +02:00
Tom Lendacky
d44df1d73c docs/interop/firmware.json: Add SEV-ES support
Create an enum definition, '@amd-sev-es', for SEV-ES and add documention
for the new enum. Add an example that shows some of the requirements for
SEV-ES, including not having SMM support and the requirement for an
X64-only build.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Message-Id: <b941a7ee105dfeb67607cf2d24dafcb82658b212.1619208498.git.thomas.lendacky@amd.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2021-06-17 14:11:06 -04:00
Daniel P. Berrangé
e0bd0cd43e docs: add table of contents to QAPI references
The QAPI reference docs for the guest agent, storage daemon and QMP are
all rather long and hard to navigate unless you already know the name of
the command and can do full text search for it.

A table of contents in each doc will help people locate stuff much more
easily.

Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2021-06-14 13:28:50 +01:00
Marc-André Lureau
73e6aec652 sphinx: adopt kernel readthedoc theme
The default "alabaster" sphinx theme has a couple shortcomings:
- the navbar moves along the page
- the search bar is not always at the same place
- it lacks some contrast and colours

The "rtd" theme from readthedocs.org is a popular third party theme used
notably by the kernel, with a custom style sheet. I like it better,
perhaps others do too. It also simplifies the "Edit on Gitlab" links.

Tweak a bit the custom theme to match qemu.org style, use the
QEMU logo, and favicon etc.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Message-Id: <20210323115328.4146052-1-marcandre.lureau@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2021-05-14 15:05:03 +04:00
Marc-André Lureau
816f93b200 docs: simplify each section title
Now that we merged into one doc, it makes the nav looks nicer.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20210323074704.4078381-1-marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2021-04-01 15:27:44 +04:00
Vladimir Sementsov-Ogievskiy
67ae4ace9b parallels.txt: fix bitmap L1 table description
Actually L1 table entry offset is in 512 bytes sectors. Fix the spec.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210224104707.88430-3-vsementsov@virtuozzo.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-03-08 14:56:54 +01:00
Peter Maydell
fe352f5c00 ui/console: message surface tweaks.
ui/cocoa: bugfixes and cleanups.
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Merge remote-tracking branch 'remotes/kraxel/tags/ui-20210304-pull-request' into staging

ui/console: message surface tweaks.
ui/cocoa: bugfixes and cleanups.

# gpg: Signature made Thu 04 Mar 2021 08:36:53 GMT
# gpg:                using RSA key A0328CFFB93A17A79901FE7D4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>" [full]
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>" [full]
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>" [full]
# Primary key fingerprint: A032 8CFF B93A 17A7 9901  FE7D 4CB6 D8EE D3E8 7138

* remotes/kraxel/tags/ui-20210304-pull-request:
  virtio-gpu: Do not distinguish the primary console
  ui/console: Pass placeholder surface to displays
  ui/console: Add placeholder flag to message surface
  ui/cocoa: Replace fprintf with error_report
  configure: Improve OpenGL dependency detections
  ui/cocoa: Fix stride resolution of pixman image
  ui/gtk: vte: fix sending multiple characeters
  ui/cocoa: Remove the uses of full screen APIs

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-03-04 12:58:50 +00:00
Akihiko Odaki
bc6a3565c8 configure: Improve OpenGL dependency detections
This has the following visible changes:

- GBM is required only for OpenGL dma-buf.
- X11 is explicitly required by gtk-egl.
- EGL is now mandatory for the OpenGL displays.

The last one needs some detailed description. Before this change,
EGL was tested only for OpenGL dma-buf with the check of
EGL_MESA_image_dma_buf_export. However, all of the OpenGL
displays depend on EGL and EGL_MESA_image_dma_buf_export is always
defined by epoxy's EGL interface.
Therefore, it makes more sense to always check the presence of EGL
and say the OpenGL displays are available along with OpenGL dma-buf
if it is present.

Signed-off-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Message-Id: <20210223060307.87736-1-akihiko.odaki@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2021-03-04 09:35:30 +01:00
Daniel P. Berrangé
1bd39ea911 docs: update to show preferred boolean syntax for -cpu
The preferred syntax is to use "foo=on|off", rather than a bare
"+foo" or "-foo"

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210216191027.595031-10-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-25 14:14:33 +01:00
Daniel P. Berrangé
c23874132b docs: update to show preferred boolean syntax for -chardev
The preferred syntax is to use "foo=on|off", rather than a bare
"foo" or "nofoo".

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210216191027.595031-8-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-25 14:14:33 +01:00
Denis V. Lunev
eb847c4229 docs: fix Parallels Image "dirty bitmap" section
Original specification says that l1 table size if 64 * l1_size, which
is obviously wrong. The size of the l1 entry is 64 _bits_, not bytes.
Thus 64 is to be replaces with 8 as specification says about bytes.

There is also minor tweak, field name is renamed from l1 to l1_table,
which matches with the later text.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20210128171313.2210947-1-den@openvz.org
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

[Replace the original commit message "docs: fix mistake in dirty bitmap
feature description" as suggested by Eric Blake.
--Stefan]

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2021-02-10 09:23:28 +00:00
Markus Armbruster
781386afd2 docs/interop/qmp-spec: Document the request queue limit
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210127144734.2367693-1-armbru@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2021-02-04 13:20:29 +01:00
Peter Maydell
b93f4fbdc4 docs: Build and install all the docs in a single manual
When we first converted our documentation to Sphinx, we split it into
multiple manuals (system, interop, tools, etc), which are all built
separately.  The primary driver for this was wanting to be able to
avoid shipping the 'devel' manual to end-users.  However, this is
working against the grain of the way Sphinx wants to be used and
causes some annoyances:
 * Cross-references between documents become much harder or
   possibly impossible
 * There is no single index to the whole documentation
 * Within one manual there's no links or table-of-contents info
   that lets you easily navigate to the others
 * The devel manual doesn't get published on the QEMU website
   (it would be nice to able to refer to it there)

Merely hiding our developer documentation from end users seems like
it's not enough benefit for these costs.  Combine all the
documentation into a single manual (the same way that the readthedocs
site builds it) and install the whole thing.  The previous manual
divisions remain as the new top level sections in the manual.

 * The per-manual conf.py files are no longer needed
 * The man_pages[] specifications previously in each per-manual
   conf.py move to the top level conf.py
 * docs/meson.build logic is simplified as we now only need to run
   Sphinx once for the HTML and then once for the manpages5B
 * The old index.html.in that produced the top-level page with
   links to each manual is no longer needed

Unfortunately this means that we now have to build the HTML
documentation into docs/manual in the build tree rather than directly
into docs/; otherwise it is too awkward to ensure we install only the
built manual and not also the dependency info, stamp file, etc.  The
manual still ends up in the same place in the final installed
directory, but anybody who was consulting documentation from within
the build tree will have to adjust where they're looking.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20210115154449.4801-1-peter.maydell@linaro.org
2021-01-19 15:45:14 +00:00
Stefan Hajnoczi
23c02ace35 docs: generate qemu-storage-daemon-qmp-ref(7) man page
Although individual qemu-storage-daemon QMP commands are identical to
QEMU QMP commands, qemu-storage-daemon only supports a subset of QEMU's
QMP commands. Generate a manual page of just the commands supported by
qemu-storage-daemon so that users know exactly what is available in
qemu-storage-daemon.

Add an h1 heading in storage-daemon/qapi/qapi-schema.json so that
block-core.json is at the h2 heading level.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20201209103802.350848-2-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-12-18 11:48:39 +01:00
Stefan Weil
ac9574bc87 docs: Fix some typos (found by codespell)
Fix also a similar typo in a code comment.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Message-Id: <20201117193448.393472-1-sw@weilnetz.de>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-11-18 09:29:41 +01:00
Stefan Hajnoczi
3009edff81 vhost-user: fix VHOST_USER_ADD/REM_MEM_REG truncation
QEMU currently truncates the mmap_offset field when sending
VHOST_USER_ADD_MEM_REG and VHOST_USER_REM_MEM_REG messages. The struct
layout looks like this:

  typedef struct VhostUserMemoryRegion {
      uint64_t guest_phys_addr;
      uint64_t memory_size;
      uint64_t userspace_addr;
      uint64_t mmap_offset;
  } VhostUserMemoryRegion;

  typedef struct VhostUserMemRegMsg {
      uint32_t padding;
      /* WARNING: there is a 32-bit hole here! */
      VhostUserMemoryRegion region;
  } VhostUserMemRegMsg;

The payload size is calculated as follows when sending the message in
hw/virtio/vhost-user.c:

  msg->hdr.size = sizeof(msg->payload.mem_reg.padding) +
      sizeof(VhostUserMemoryRegion);

This calculation produces an incorrect result of only 36 bytes.
sizeof(VhostUserMemRegMsg) is actually 40 bytes.

The consequence of this is that the final field, mmap_offset, is
truncated. This breaks x86_64 TCG guests on s390 hosts. Other guest/host
combinations may get lucky if either of the following holds:
1. The guest memory layout does not need mmap_offset != 0.
2. The host is little-endian and mmap_offset <= 0xffffffff so the
   truncation has no effect.

Fix this by extending the existing 32-bit padding field to 64-bit. Now
the padding reflects the actual compiler padding. This can be verified
using pahole(1).

Also document the layout properly in the vhost-user specification.  The
vhost-user spec did not document the exact layout. It would be
impossible to implement the spec without looking at the QEMU source
code.

Existing vhost-user frontends and device backends continue to work after
this fix has been applied. The only change in the wire protocol is that
QEMU now sets hdr.size to 40 instead of 36. If a vhost-user
implementation has a hardcoded size check for 36 bytes, then it will
fail with new QEMUs. Both QEMU and DPDK/SPDK don't check the exact
payload size, so they continue to work.

Fixes: f1aeb14b08 ("Transmit vhost-user memory regions individually")
Cc: Raphael Norwitz <raphael.norwitz@nutanix.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20201109174355.1069147-1-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Fixes: f1aeb14b08 ("Transmit vhost-user memory regions individually")
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
2020-11-12 09:19:40 -05:00
Daniel P. Berrangé
704a256da8 docs: add "page source" link to sphinx documentation
Add a link to the top of the sidebar in every docs page that takes the
user back to the source code in gitlab.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20201102130926.161183-5-berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-11-10 08:51:30 +01:00
Eric Blake
71719cd57f nbd: Add new qemu:allocation-depth metadata context
'qemu-img map' provides a way to determine which extents of an image
come from the top layer vs. inherited from a backing chain.  This is
useful information worth exposing over NBD.  There is a proposal to
add a QMP command block-dirty-bitmap-populate which can create a dirty
bitmap that reflects allocation information, at which point the
qemu:dirty-bitmap:NAME metadata context can expose that information
via the creation of a temporary bitmap, but we can shorten the effort
by adding a new qemu:allocation-depth metadata context that does the
same thing without an intermediate bitmap (this patch does not
eliminate the need for that proposal, as it will have other uses as
well).

While documenting things, remember that although the NBD protocol has
NBD_OPT_SET_META_CONTEXT, the rest of its documentation refers to
'metadata context', which is a more apt description of what is
actually being used by NBD_CMD_BLOCK_STATUS: the user is requesting
metadata by passing one or more context names.  So I also touched up
some existing wording to prefer the term 'metadata context' where it
makes sense.

Note that this patch does not actually enable any way to request a
server to enable this context; that will come in the next patch.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20201027050556.269064-10-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
2020-10-30 15:22:00 -05:00
Pavel Dovgalyuk
bbacffc5f7 qcow2: introduce icount field for snapshots
This patch introduces the icount field for saving within the snapshot.
It is required for navigation between the snapshots in record/replay mode.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
Acked-by: Kevin Wolf <kwolf@redhat.com>

--

v7 changes:
 - also fix the test which checks qcow2 snapshot extra data
Message-Id: <160174518284.12451.2301137308458777398.stgit@pasha-ThinkPad-X280>

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-10-06 08:34:49 +02:00
Peter Maydell
4ac2ee194b docs/interop: Convert qemu-qmp-ref to rST
Convert qemu-qmp-ref to rST format. This includes dropping
the plain-text, pdf and info format outputs for this document;
as with all our other Sphinx-based documentation, we provide
HTML and manpage only.

The qemu-qmp-ref.rst is somewhat more stripped down than
the .texi was, because we do not (currently) attempt to
generate indexes for the commands, events and data types
being documented.

Again, we drop the direct link from index.html.in now that
the QMP ref is part of the interop manual.

This commit removes the code from the root meson.build file that
handled the various Texinfo-based outputs, because we no longer
generate any documentation except for the Sphinx HTML manuals and the
manpages, and the code can't handle having an empty list of files
to process.. We'll do further cleanup of the remainders of
Texinfo support in subsequent commits.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200925162316.21205-10-peter.maydell@linaro.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Unicode legacy literal dumbed down to plain string literal, TODO
comment on displaying QEMU version added, "make html" fixed,
storage-daemon/qapi/meson.build updated]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2020-09-29 17:55:39 +02:00
Peter Maydell
db16115f87 docs/interop: Convert qemu-ga-ref to rST
Convert qemu-ga-ref to rST format. This includes dropping
the plain-text, pdf and info format outputs for this document;
as with all our other Sphinx-based documentation, we provide
HTML and manpage only.

The qemu-ga-ref.rst is somewhat more stripped down than
the .texi was, because we do not (currently) attempt to
generate indexes for the commands, events and data types
being documented.

As the GA ref is now part of the Sphinx 'interop' manual,
we can delete the direct link from index.html.in.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200925162316.21205-9-peter.maydell@linaro.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Unicode legacy literal dumbed down to plain string literal, TODO
comment on displaying QEMU version added]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2020-09-29 17:55:39 +02:00
zhaolichang
76ca4b58c2 docs/: fix some comment spelling errors
I found that there are many spelling errors in the comments of qemu,
so I used the spellcheck tool to check the spelling errors
and finally found some spelling errors in the docs folder.

Signed-off-by: zhaolichang <zhaolichang@huawei.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200917075029.313-4-zhaolichang@huawei.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2020-09-17 20:37:13 +02:00
Markus Armbruster
a7742549ea docs/interop/qmp-spec: Point to the QEMU QMP reference manual
Commit 4d8bb958fa0..231aaf3a821 integrated the contents of
docs/qmp-events.txt into QAPI schema doc comments.  It left dangling
references to qmp-events.txt behind.  Fix to point to the QEMU QMP
reference manual generated from the QAPI schema.

Add a similar reference for commands.

Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200806081147.3123652-2-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2020-09-03 09:58:02 +02:00
Alberto Garcia
30afc12085 qcow2: Document the Extended L2 Entries feature
Subcluster allocation in qcow2 is implemented by extending the
existing L2 table entries and adding additional information to
indicate the allocation status of each subcluster.

This patch documents the changes to the qcow2 format and how they
affect the calculation of the L2 cache size.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <5199f2e1c717bcaa58b48142c9062b803145ff7f.1594396418.git.berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-08-25 08:33:20 +02:00
Paolo Bonzini
acfdaac577 meson: build texi doc
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-08-21 06:30:42 -04:00
Paolo Bonzini
64ed6f92ff meson: link emulators without Makefile.target
The binaries move to the root directory, e.g. qemu-system-i386 or
qemu-arm.  This requires changes to qtests, CI, etc.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-08-21 06:30:40 -04:00
Andrea Bolognani
f7160f3218 schemas: Add vim modeline
The various schemas included in QEMU use a JSON-based format which
is, however, strictly speaking not valid JSON.

As a consequence, when vim tries to apply syntax highlight rules
for JSON (as guessed from the file name), the result is an unreadable
mess which mostly consist of red markers pointing out supposed errors
in, well, pretty much everything.

Using Python syntax highlighting produces much better results, and
in fact these files already start with specially-formatted comments
that instruct Emacs to process them as if they were Python files.

This commit adds the equivalent special comments for vim.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Message-Id: <20200729185024.121766-1-abologna@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2020-08-03 08:28:08 +02:00
Andrey Shinkevich
8098969cf2 qcow2: Fix capitalization of header extension constant.
Make the capitalization of the hexadecimal numbers consistent for the
QCOW2 header extension constants in docs/interop/qcow2.txt.

Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <1594973699-781898-2-git-send-email-andrey.shinkevich@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2020-07-27 15:39:58 -05:00
Cindy Lu
108a64818e vhost-vdpa: introduce vhost-vdpa backend
Currently we have 2 types of vhost backends in QEMU: vhost kernel and
vhost-user. The above patch provides a generic device for vDPA purpose,
this vDPA device exposes to user space a non-vendor-specific configuration
interface for setting up a vhost HW accelerator, this patch set introduces
a third vhost backend called vhost-vdpa based on the vDPA interface.

Vhost-vdpa usage:

qemu-system-x86_64 -cpu host -enable-kvm \
    ......
    -netdev type=vhost-vdpa,vhostdev=/dev/vhost-vdpa-id,id=vhost-vdpa0 \
    -device virtio-net-pci,netdev=vhost-vdpa0,page-per-vq=on \

Signed-off-by: Lingshan zhu <lingshan.zhu@intel.com>
Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: Cindy Lu <lulu@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20200701145538.22333-14-lulu@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-07-07 07:59:51 -04:00
Maxime Coquelin
553dc662bb docs: vhost-user: add Virtio status protocol feature
This patch specifies the VHOST_USER_SET_STATUS and
VHOST_USER_GET_STATUS requests, which are sent by
the master to update and query the Virtio status
in the backend.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Message-Id: <20200618134501.145747-1-maxime.coquelin@redhat.com>
Acked-by: Jason Wang <jasowang@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>
2020-07-03 07:57:04 -04:00
Raphael Norwitz
27598393a2 Lift max memory slots limit imposed by vhost-user
Historically, sending all memory regions to vhost-user backends in a
single message imposed a limitation on the number of times memory
could be hot-added to a VM with a vhost-user device. Now that backends
which support the VHOST_USER_PROTOCOL_F_CONFIGURE_SLOTS send memory
regions individually, we no longer need to impose this limitation on
devices which support this feature.

With this change, VMs with a vhost-user device which supports the
VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS can support a configurable
number of memory slots, up to the maximum allowed by the target
platform.

Existing backends which do not support
VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS are unaffected.

Signed-off-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Signed-off-by: Peter Turschmid <peter.turschm@nutanix.com>
Suggested-by: Mike Cui <cui@nutanix.com>
Message-Id: <1588533678-23450-6-git-send-email-raphael.norwitz@nutanix.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>
2020-06-12 10:17:06 -04:00
Raphael Norwitz
f1aeb14b08 Transmit vhost-user memory regions individually
With this change, when the VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS
protocol feature has been negotiated, Qemu no longer sends the backend
all the memory regions in a single message. Rather, when the memory
tables are set or updated, a series of VHOST_USER_ADD_MEM_REG and
VHOST_USER_REM_MEM_REG messages are sent to transmit the regions to map
and/or unmap instead of sending send all the regions in one fixed size
VHOST_USER_SET_MEM_TABLE message.

The vhost_user struct maintains a shadow state of the VM’s memory
regions. When the memory tables are modified, the
vhost_user_set_mem_table() function compares the new device memory state
to the shadow state and only sends regions which need to be unmapped or
mapped in. The regions which must be unmapped are sent first, followed
by the new regions to be mapped in. After all the messages have been
sent, the shadow state is set to the current virtual device state.

Existing backends which do not support
VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS are unaffected.

Signed-off-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Signed-off-by: Swapnil Ingle <swapnil.ingle@nutanix.com>
Signed-off-by: Peter Turschmid <peter.turschm@nutanix.com>
Suggested-by: Mike Cui <cui@nutanix.com>
Message-Id: <1588533678-23450-5-git-send-email-raphael.norwitz@nutanix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2020-06-12 10:17:06 -04:00
Raphael Norwitz
6b0eff1a4e Add VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS
This change introduces a new feature to the vhost-user protocol allowing
a backend device to specify the maximum number of ram slots it supports.

At this point, the value returned by the backend will be capped at the
maximum number of ram slots which can be supported by vhost-user, which
is currently set to 8 because of underlying protocol limitations.

The returned value will be stored inside the VhostUserState struct so
that on device reconnect we can verify that the ram slot limitation
has not decreased since the last time the device connected.

Signed-off-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Signed-off-by: Peter Turschmid <peter.turschm@nutanix.com>
Message-Id: <1588533678-23450-4-git-send-email-raphael.norwitz@nutanix.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>
2020-06-12 10:17:06 -04:00
Denis Plotnikov
d298ac10ad qcow2: add zstd cluster compression
zstd significantly reduces cluster compression time.
It provides better compression performance maintaining
the same level of the compression ratio in comparison with
zlib, which, at the moment, is the only compression
method available.

The performance test results:
Test compresses and decompresses qemu qcow2 image with just
installed rhel-7.6 guest.
Image cluster size: 64K. Image on disk size: 2.2G

The test was conducted with brd disk to reduce the influence
of disk subsystem to the test results.
The results is given in seconds.

compress cmd:
  time ./qemu-img convert -O qcow2 -c -o compression_type=[zlib|zstd]
                  src.img [zlib|zstd]_compressed.img
decompress cmd
  time ./qemu-img convert -O qcow2
                  [zlib|zstd]_compressed.img uncompressed.img

           compression               decompression
         zlib       zstd           zlib         zstd
------------------------------------------------------------
real     65.5       16.3 (-75 %)    1.9          1.6 (-16 %)
user     65.0       15.8            5.3          2.5
sys       3.3        0.2            2.0          2.0

Both ZLIB and ZSTD gave the same compression ratio: 1.57
compressed image size in both cases: 1.4G

Signed-off-by: Denis Plotnikov <dplotnikov@virtuozzo.com>
QAPI part:
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200507082521.29210-4-dplotnikov@virtuozzo.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-05-13 14:20:31 +02:00
Alberto Garcia
a50c1f57e4 qcow2: Add incompatibility note between backing files and raw external data files
Backing files and raw external data files are mutually exclusive.
The documentation of the raw external data bit (in autoclear_features)
already indicates that, but we should also mention it on the other
side.

Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-Id: <20200410121816.8334-1-berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-04-30 17:51:06 +02:00
Eric Blake
bb40ebce2c qcow2: List autoclear bit names in header
The feature table is supposed to advertise the name of all feature
bits that we support; however, we forgot to update the table for
autoclear bits.  While at it, move the table to read-only memory in
code, and tweak the qcow2 spec to name the second autoclear bit.
Update iotests that are affected by the longer header length.

Fixes: 88ddffae
Fixes: 93c24936
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200324174233.1622067-3-eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-03-26 14:44:33 +01:00
Stefan Hajnoczi
7b46aadbbf qemu-ga: document vsock-listen in the man page
Although qemu-ga has supported vsock since 2016 it was not documented on
the man page.

Also add the socket address representation to the qga --help output.

Fixes: 586ef5dee7
       ("qga: add vsock-listen method")
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
2020-03-24 11:32:19 -05:00
Philippe Mathieu-Daudé
880a7817c1 misc: Replace zero-length arrays with flexible array member (manual)
Description copied from Linux kernel commit from Gustavo A. R. Silva
(see [3]):

--v-- description start --v--

  The current codebase makes use of the zero-length array language
  extension to the C90 standard, but the preferred mechanism to
  declare variable-length types such as these ones is a flexible
  array member [1], introduced in C99:

  struct foo {
      int stuff;
      struct boo array[];
  };

  By making use of the mechanism above, we will get a compiler
  warning in case the flexible array does not occur last in the
  structure, which will help us prevent some kind of undefined
  behavior bugs from being unadvertenly introduced [2] to the
  Linux codebase from now on.

--^-- description end --^--

Do the similar housekeeping in the QEMU codebase (which uses
C99 since commit 7be41675f7).

All these instances of code were found with the help of the
following command (then manual analysis, without modifying
structures only having a single flexible array member, such
QEDTable in block/qed.h):

  git grep -F '[0];'

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=76497732932f
[3] https://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux.git/commit/?id=17642a2fbd2c1

Inspired-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 22:07:42 +01:00
Johannes Berg
3348e7e34f docs: vhost-user: add in-band kick/call messages
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>
2020-02-27 03:46:10 -05:00
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'
 -----BEGIN PGP SIGNATURE-----
 
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 -----END PGP SIGNATURE-----

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