Commit Graph

348 Commits

Author SHA1 Message Date
Dr. David Alan Gilbert 2bfdd1c8a6 Add postcopy documentation
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-11-10 14:51:48 +01:00
Eric Blake f545504420 qapi-introspect: Document lack of sorting
qapi-code-gen.txt already claims that types, commands, and
events share a common namespace; set this in stone by further
documenting that our introspection output will never have
collisions with the same name tied to more than one meta-type.

Our largest QMP enum currently has 125 values, our largest
object type has 27 members, and the mean for each is less than
10.  These sizes are small enough that the per-element overhead
of O(log n) binary searching probably outweighs the speed
possible with direct O(n) linear searching (a better algorithm
with more overhead will only beat a leaner naive algorithm only
as you scale to larger input sizes).

Arguably, the overall SchemaInfo array could be sorted by name;
there, we currently have 531 entities, large enough for a binary
search to be faster than linear.  However, remember that we have
mutually-recursive types, which means there is no topological
ordering that will allow clients to learn all information about
that type in a single linear pass; thus clients will want to do
random access over the data, and they will probably read the
introspection output into a hashtable for O(1) lookup rather
than O(log n) binary searching, at which point, pre-sorting our
introspection output doesn't help the client.

It doesn't help that sorting can be subjective if you introduce
locales into the mix (I'm not experienced enough with Python
to know for sure, but at least it looks like it defaults to
sorting in the C locale even when run under a different locale).
And while our current introspection output is deterministic
(because we visit entities in a sorted order), we may want
to change that order in the future (such as using OrderedDict
to stick to .json declaration order).

For these reasons, we simply document that clients should not
rely on any particular order of items in introspection output.
And since it is now a documented part of the contract, we have
the freedom to later rearrange output if needed, without
worrying about breaking well-written clients.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1446791754-23823-13-git-send-email-eblake@redhat.com>
[Commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-11-10 08:10:28 +01:00
Eric Blake ce5fcb472d qapi: Provide nicer array names in introspection
For the sake of humans reading introspection output, it is nice
to have the name of implicit array types be recognizable as
arrays of the underlying type.  However, while this patch allows
humans to skip from a command with return type "[123]" straight
to the definition of type "123" without having to first inspect
type "[123]", document that this shortcut should not be taken by
client apps.

This makes the resulting introspection string slightly larger by
default (just over 200 bytes), but it's in the noise (less than
0.3% of the overall 70k size of 'query-qmp-capabilities').

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1446791754-23823-12-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-11-10 08:09:15 +01:00
Pavel Dovgalyuk d73abd6dcc replay: global variables and function stubs
This patch adds global variables, defines, function declarations,
and function stubs for deterministic VM replay used by external modules.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>

Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Message-Id: <20150917162337.8676.41538.stgit@PASHA-ISP.def.inno>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-05 12:19:08 +01:00
Eric Blake 9fb081e0b9 qapi: Reserve 'q_*' and 'has_*' member names
c_name() produces names starting with 'q_' when protecting a
dictionary member name that would fail to directly compile, but
in doing so can cause clashes with any member name already
beginning with 'q-' or 'q_'.  Likewise, we create a C name 'has_'
for any optional member that can clash with any member name
beginning with 'has-' or 'has_'.

Technically, rather than blindly reserving the namespace,
we could try to complain about user names only when an actual
collision occurs, or even teach c_name() how to munge names
to avoid collisions.  But it is not trivial, especially when
collisions can occur across multiple types (such as via
inheritance or flat unions).  Besides, no existing .json
files are trying to use these names.  So it's easier to just
outright forbid the potential for collision.  We can always
relax things in the future if a real need arises for QMP to
express member names that have been forbidden here.

'has_' only has to be reserved for struct/union member names,
while 'q_' is reserved everywhere (matching the fact that
only members can be optional, while we use c_name() for munging
both members and entities).  Note that we could relax 'q_'
restrictions on entities independently from member names; for
example, c_name('qmp_' + 'unix') would result in a different
function name than our current 'qmp_' + c_name('unix').

Update and add tests to cover the new error messages.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1445898903-12082-6-git-send-email-eblake@redhat.com>
[Consistently pass protect=False to c_name(); commit message tweaked
slightly]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-11-02 08:30:26 +01:00
Eric Blake 255960dd37 qapi: Reserve '*List' type names for list types
Type names ending in 'List' can clash with qapi list types in
generated C.  We don't currently use such names. It is easier to
outlaw them now than to worry about how to resolve such a clash
in the future. For precedence, see commit 4dc2e69, which did the
same for names ending in 'Kind' versus implicit enum types for
qapi unions.

Update the testsuite to match.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1445898903-12082-5-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-11-02 08:30:26 +01:00
Markus Armbruster 7f1e7b23d5 docs: Document QMP event rate limiting
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1444921716-9511-8-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-10-30 09:05:38 +01:00
Marc-André Lureau f7a199b2b4 ivshmem: use little-endian int64_t for the protocol
The current ivshmem protocol uses 'long' for integers. But the
sizeof(long) depends on the host and the endianess is not defined, which
may cause portability troubles.

Instead, switch to using little-endian int64_t. This breaks the
protocol, except on x64 little-endian host where this change
should be compatible.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Claudio Fontana <claudio.fontana@huawei.com>
2015-10-26 10:19:53 +01:00
David Marchand 5105b1d8c2 ivshmem: add check on protocol version in QEMU
Send a protocol version as the first message from server, clients must
close communication if they don't support this protocol version.  Older
QEMUs should be fine with this change in the protocol since they
overrides their own vm_id on reception of an id associated to no
eventfd.

Signed-off-by: David Marchand <david.marchand@6wind.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[use fifo_update_and_get()]
Reviewed-by: Claudio Fontana <claudio.fontana@huawei.com>
2015-10-24 18:03:18 +02:00
David Marchand 8c4ef202b9 docs: update ivshmem device spec
Add some notes on the parts needed to use ivshmem devices: more specifically,
explain the purpose of an ivshmem server and the basic concept to use the
ivshmem devices in guests.
Move some parts of the documentation and re-organise it.

Signed-off-by: David Marchand <david.marchand@6wind.com>
Reviewed-by: Claudio Fontana <claudio.fontana@huawei.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2015-10-24 18:03:17 +02:00
Peter Maydell ca3e40e233 vhost, pc, virtio features, fixes, cleanups
New features:
     VT-d support for devices behind a bridge
     vhost-user migration support
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

vhost, pc, virtio features, fixes, cleanups

New features:
    VT-d support for devices behind a bridge
    vhost-user migration support

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

# gpg: Signature made Thu 22 Oct 2015 12:39:19 BST using RSA key ID D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>"

* remotes/mst/tags/for_upstream: (37 commits)
  hw/isa/lpc_ich9: inject the SMI on the VCPU that is writing to APM_CNT
  i386: keep cpu_model field in MachineState uptodate
  vhost: set the correct queue index in case of migration with multiqueue
  piix: fix resource leak reported by Coverity
  seccomp: add memfd_create to whitelist
  vhost-user-test: check ownership during migration
  vhost-user-test: add live-migration test
  vhost-user-test: learn to tweak various qemu arguments
  vhost-user-test: wrap server in TestServer struct
  vhost-user-test: remove useless static check
  vhost-user-test: move wait_for_fds() out
  vhost: add migration block if memfd failed
  vhost-user: use an enum helper for features mask
  vhost user: add rarp sending after live migration for legacy guest
  vhost user: add support of live migration
  net: add trace_vhost_user_event
  vhost-user: document migration log
  vhost: use a function for each call
  vhost-user: add a migration blocker
  vhost-user: send log shm fd along with log_base
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-10-22 12:41:44 +01:00
Thibaut Collet 3e866365e1 vhost user: add rarp sending after live migration for legacy guest
A new vhost user message is added to allow QEMU to ask to vhost user backend to
broadcast a fake RARP after live migration for guest without GUEST_ANNOUNCE
capability.

This new message is sent only if the backend supports the new
VHOST_USER_PROTOCOL_F_RARP protocol feature.
The payload of this new message is the MAC address of the guest (not known by
the backend). The MAC address is copied in the first 6 bytes of a u64 to avoid
to create a new payload message type.

This new message has no equivalent ioctl so a new callback is added in the
userOps structure to send the request.

Upon reception of this new message the vhost user backend must generate and
broadcast a fake RARP request to notify the migration is terminated.

Signed-off-by: Thibaut Collet <thibaut.collet@6wind.com>
[Rebased and fixed checkpatch errors - Marc-André]
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Thibaut Collet <thibaut.collet@6wind.com>
2015-10-22 14:34:49 +03:00
Marc-André Lureau c62b91e580 vhost-user: document migration log
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Thibaut Collet <thibaut.collet@6wind.com>
2015-10-22 14:34:49 +03:00
Cornelia Huck 22de58fe15 virtio: add some migration doc
Try to cover the basics of virtio migration.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
2015-10-22 14:34:48 +03:00
Kevin O'Connor 2cc06a8843 fw_cfg: Define a static signature to be returned on DMA port reads
Return a static signature ("QEMU CFG") if the guest does a read to the
DMA address io register.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2015-10-19 15:26:54 +02:00
Marc Marí c9eae1d4b9 fw_cfg DMA interface documentation
Add fw_cfg DMA interface specification in the documentation.

Based on Gerd Hoffman's initial implementation.

Signed-off-by: Marc Marí <markmb@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2015-10-19 15:26:53 +02:00
Gabriel L. Somlo 57c3d238a5 fw_cfg: document fw_cfg_modify_iXX() update functions
Document the behavior of fw_cfg_modify_iXX() for leak-less updating
of integer-type blobs.

Currently only fw_cfg_modify_i16() is coded, but 32- and 64-bit versions
may be added later if necessary..

Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2015-10-19 15:26:53 +02:00
Gabriel L. Somlo 6407d76eb4 fw_cfg: insert string blobs via qemu cmdline
Allow users to provide custom fw_cfg blobs with ascii string
payloads specified directly on the qemu command line.

Suggested-by: Jordan Justen <jordan.l.justen@intel.com>
Suggested-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
Message-id: 1443544141-26568-1-git-send-email-somlo@cmu.edu
Reviewd-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2015-10-19 15:26:53 +02:00
Peter Maydell 526d5809a0 * KVM page size fix for PPC
* Support for Linux 4.4's new Hyper-V features
 * Eliminate g_slice from areas I maintain
 * checkpatch fix
 * Peter's cpu_reload_memory_map() cleanups
 * More changes to MAINTAINERS
 * Require Python 2.6
 * chardev creation fixes
 * PCI requester id for ARM KVM
 * cleanups and doc fixes
 * Allow customization of the Hyper-V vendor id
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

* KVM page size fix for PPC
* Support for Linux 4.4's new Hyper-V features
* Eliminate g_slice from areas I maintain
* checkpatch fix
* Peter's cpu_reload_memory_map() cleanups
* More changes to MAINTAINERS
* Require Python 2.6
* chardev creation fixes
* PCI requester id for ARM KVM
* cleanups and doc fixes
* Allow customization of the Hyper-V vendor id

# gpg: Signature made Mon 19 Oct 2015 09:13:10 BST using RSA key ID 78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"

* remotes/bonzini/tags/for-upstream: (49 commits)
  kvm: Allow the Hyper-V vendor ID to be specified
  kvm: Move x86-specific functions into target-i386/kvm.c
  kvm: Pass PCI device pointer to MSI routing functions
  hw/pci: Introduce pci_requester_id()
  kvm: Make KVM_CAP_SIGNAL_MSI globally available
  doc/rcu: fix g_free_rcu() usage example
  qemu-char: cleanup after completed conversion to cd->create
  qemu-char: convert ringbuf backend to data-driven creation
  qemu-char: convert vc backend to data-driven creation
  qemu-char: convert spice backend to data-driven creation
  qemu-char: convert console backend to data-driven creation
  qemu-char: convert stdio backend to data-driven creation
  qemu-char: convert testdev backend to data-driven creation
  qemu-char: convert braille backend to data-driven creation
  qemu-char: convert msmouse backend to data-driven creation
  qemu-char: convert mux backend to data-driven creation
  qemu-char: convert null backend to data-driven creation
  qemu-char: convert pty backend to data-driven creation
  qemu-char: convert UDP backend to data-driven creation
  qemu-char: convert socket backend to data-driven creation
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-10-19 10:52:39 +01:00
Sergey Fedorov 9bda456e41 doc/rcu: fix g_free_rcu() usage example
The first argument of g_free_rcu() is a pointer to a structure.  But
foo_reclaim is used as a function name in the previous example along
with &foo as a pointer to the structure being reclaimed.  Make the
example consistent with the previous one.

Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Message-Id: <1444837604-13712-1-git-send-email-serge.fdrv@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-19 10:13:07 +02:00
Eric Blake f8b7f1a8ea qapi: Consistent generated code: prefer visitor 'v'
We had some pointless differences in the generated code for visit,
command marshalling, and events; unifying them makes it easier for
future patches to consolidate to common helper functions.
This is one patch of a series to clean up these differences.

This patch names the local visitor variable 'v' rather than 'm'.
Related objects, such as 'QapiDeallocVisitor', are also named by
their initials instead of an unrelated leading m.

No change in semantics to the generated code.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-12-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-10-12 18:46:49 +02:00
Eric Blake 2a0f50e8d9 qapi: Consistent generated code: prefer error 'err'
We had some pointless differences in the generated code for visit,
command marshalling, and events; unifying them makes it easier for
future patches to consolidate to common helper functions.
This is one patch of a series to clean up these differences.

This patch consistently names the local error variable 'err' rather
than 'local_err'.

No change in semantics to the generated code.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-11-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-10-12 18:46:49 +02:00
Markus Armbruster 9b89b6a287 docs: Move files from docs/qmp/ to docs/
Giving QMP its own subdirectory in docs/ is hardly worthwhile when we
have just four files, and one of them isn't even in the subdirectory.
Move the files from docs/qmp/ to docs/, renaming docs/qmp/README to
docs/qmp-intro.

Update MAINTAINERS.  The new pattern also captures the fourth file
docs/writing-qmp-commands.txt.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1443111117-29831-2-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-10-12 18:44:53 +02:00
Lin Ma 2e4ccbbc64 docs: update the usage example of "dtrace" backend in tracing.txt
The usage example of dtrace is quite ancient, We have tracetool.py with
different parameters instead of the original tracetool shell script for
a long time, So update the old information.

Signed-off-by: Lin Ma <lma@suse.com>
Message-id: 1441954730-17341-1-git-send-email-lma@suse.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-10-09 10:14:05 +01:00
Peter Maydell 9e071429e6 * First batch of MAINTAINERS updates
* IOAPIC fixes (to pass kvm-unit-tests with -machine kernel_irqchip=off)
 * NBD API upgrades from Daniel
 * strtosz fixes from Marc-André
 * improved support for readonly=on on scsi-generic devices
 * new "info ioapic" and "info lapic" monitor commands
 * Peter Crosthwaite's ELF_MACHINE cleanups
 * docs patches from Thomas and Daniel
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

* First batch of MAINTAINERS updates
* IOAPIC fixes (to pass kvm-unit-tests with -machine kernel_irqchip=off)
* NBD API upgrades from Daniel
* strtosz fixes from Marc-André
* improved support for readonly=on on scsi-generic devices
* new "info ioapic" and "info lapic" monitor commands
* Peter Crosthwaite's ELF_MACHINE cleanups
* docs patches from Thomas and Daniel

# gpg: Signature made Fri 25 Sep 2015 11:20:52 BST using RSA key ID 78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"

* remotes/bonzini/tags/for-upstream: (52 commits)
  doc: Refresh URLs in the qemu-tech documentation
  docs: describe the QEMU build system structure / design
  typedef: add typedef for QemuOpts
  i386: interrupt poll processing
  i386: partial revert of interrupt poll fix
  ppc: Rename ELF_MACHINE to be PPC specific
  i386: Rename ELF_MACHINE to be x86 specific
  alpha: Remove ELF_MACHINE from cpu.h
  mips: Remove ELF_MACHINE from cpu.h
  sparc: Remove ELF_MACHINE from cpu.h
  s390: Remove ELF_MACHINE from cpu.h
  sh4: Remove ELF_MACHINE from cpu.h
  xtensa: Remove ELF_MACHINE from cpu.h
  tricore: Remove ELF_MACHINE from cpu.h
  or32: Remove ELF_MACHINE from cpu.h
  lm32: Remove ELF_MACHINE from cpu.h
  unicore: Remove ELF_MACHINE from cpu.h
  moxie: Remove ELF_MACHINE from cpu.h
  cris: Remove ELF_MACHINE from cpu.h
  m68k: Remove ELF_MACHINE from cpu.h
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-09-25 21:52:30 +01:00
Peter Maydell cdf9818242 virtio,pc features, fixes
New features:
     vhost-user multiqueue support
     virtio-ccw virtio 1 support
 
 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,pc features, fixes

New features:
    vhost-user multiqueue support
    virtio-ccw virtio 1 support

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

# gpg: Signature made Fri 25 Sep 2015 07:40:35 BST using RSA key ID D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>"

* remotes/mst/tags/for_upstream:
  MAINTAINERS: add more devices to the PCI section
  MAINTAINERS: add more devices to the PC section
  vhost-user: add a new message to disable/enable a specific virt queue.
  vhost-user: add multiple queue support
  vhost: introduce vhost_backend_get_vq_index method
  vhost-user: add VHOST_USER_GET_QUEUE_NUM message
  vhost: rename VHOST_RESET_OWNER to VHOST_RESET_DEVICE
  vhost-user: add protocol feature negotiation
  vhost-user: use VHOST_USER_XXX macro for switch statement
  virtio-ccw: enable virtio-1
  virtio-ccw: feature bits > 31 handling
  virtio-ccw: support ring size changes
  virtio: ring sizes vs. reset
  pc: Introduce pc-*-2.5 machine classes
  q35: Move options common to all classes to pc_i440fx_machine_options()
  q35: Move options common to all classes to pc_q35_machine_options()
  virtio-net: unbreak self announcement and guest offloads after migration
  virtio: right size for virtio_queue_get_avail_size

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-09-25 16:40:05 +01:00
Daniel P. Berrange 717171bd20 docs: describe the QEMU build system structure / design
Developers who are new to QEMU, or have a background familiarity
with GNU autotools, can have trouble getting their head around the
home-grown QEMU build system. This document attempts to explain
the structure / design of the configure script and the various
Makefile pieces that live across the source tree.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1443102098-13642-1-git-send-email-berrange@redhat.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-25 12:20:18 +02:00
Paolo Bonzini 7c9b2bf677 qemu-thread: add a fast path to the Win32 QemuEvent
QemuEvents are used heavily by call_rcu.  We do not want them to be slow,
but the current implementation does a kernel call on every invocation
of qemu_event_* and won't cut it.

So, wrap a Win32 manual-reset event with a fast userspace path.  The
states and transitions are the same as for the futex and mutex/condvar
implementations, but the slow path is different of course.  The idea
is to reset the Win32 event lazily, as part of a test-reset-test-wait
sequence.  Such a sequence is, indeed, how QemuEvents are used by
RCU and other subsystems!

The patch includes a formal model of the algorithm.

Tested-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
2015-09-24 20:52:28 +02:00
Changchun Ouyang 7263a0ad78 vhost-user: add a new message to disable/enable a specific virt queue.
Add a new message, VHOST_USER_SET_VRING_ENABLE, to enable or disable
a specific virt queue, which is similar to attach/detach queue for
tap device.

virtio driver on guest doesn't have to use max virt queue pair, it
could enable any number of virt queue ranging from 1 to max virt
queue pair.

Signed-off-by: Changchun Ouyang <changchun.ouyang@intel.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Tested-by: Marcel Apfelbaum <marcel@redhat.com>
2015-09-24 16:27:53 +03:00
Changchun Ouyang b931bfbf04 vhost-user: add multiple queue support
This patch is initially based a patch from Nikolay Nikolaev.

This patch adds vhost-user multiple queue support, by creating a nc
and vhost_net pair for each queue.

Qemu exits if find that the backend can't support the number of requested
queues (by providing queues=# option). The max number is queried by a
new message, VHOST_USER_GET_QUEUE_NUM, and is sent only when protocol
feature VHOST_USER_PROTOCOL_F_MQ is present first.

The max queue check is done at vhost-user initiation stage. We initiate
one queue first, which, in the meantime, also gets the max_queues the
backend supports.

In older version, it was reported that some messages are sent more times
than necessary. Here we came an agreement with Michael that we could
categorize vhost user messages to 2 types: non-vring specific messages,
which should be sent only once, and vring specific messages, which should
be sent per queue.

Here I introduced a helper function vhost_user_one_time_request(), which
lists following messages as non-vring specific messages:

        VHOST_USER_SET_OWNER
        VHOST_USER_RESET_DEVICE
        VHOST_USER_SET_MEM_TABLE
        VHOST_USER_GET_QUEUE_NUM

For above messages, we simply ignore them when they are not sent the first
time.

Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Signed-off-by: Changchun Ouyang <changchun.ouyang@intel.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Tested-by: Marcel Apfelbaum <marcel@redhat.com>
2015-09-24 16:27:53 +03:00
Yuanhan Liu e2051e9e00 vhost-user: add VHOST_USER_GET_QUEUE_NUM message
This is for querying how many queues the backend supports if it has mq
support(when VHOST_USER_PROTOCOL_F_MQ flag is set from the quried
protocol features).

vhost_net_get_max_queues() is the interface to export that value, and
to tell if the backend supports # of queues user requested, which is
done in the following patch.

Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Tested-by: Marcel Apfelbaum <marcel@redhat.com>
2015-09-24 16:27:52 +03:00
Yuanhan Liu d1f8b30ec8 vhost: rename VHOST_RESET_OWNER to VHOST_RESET_DEVICE
Quote from Michael:

    We really should rename VHOST_RESET_OWNER to VHOST_RESET_DEVICE.

Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Tested-by: Marcel Apfelbaum <marcel@redhat.com>
2015-09-24 16:27:52 +03:00
Michael S. Tsirkin dcb10c000c vhost-user: add protocol feature negotiation
Support a separate bitmask for vhost-user protocol features,
and messages to get/set protocol features.

Invoke them at init.

No features are defined yet.

[ leverage vhost_user_call for request handling -- Yuanhan Liu ]

Signed-off-by: Michael S. Tsirkin <address@hidden>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Tested-by: Marcel Apfelbaum <marcel@redhat.com>
2015-09-24 16:27:52 +03:00
Marc-André Lureau 7b02f5447c libcacard: use the standalone project
libcacard is now a standalone project hosted with the Spice project (see
the 2.5.0 release announcement), remove it from qemu tree.

Use the library if found during configure or if --enable-smartcard.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Tested-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-23 23:34:17 +02:00
Bharata B Rao 03d196b7c5 spapr: Support ibm,dynamic-reconfiguration-memory
Parse ibm,architecture.vec table obtained from the guest and enable
memory node configuration via ibm,dynamic-reconfiguration-memory if guest
supports it. This is in preparation to support memory hotplug for
sPAPR guests.

This changes the way memory node configuration is done. Currently all
memory nodes are built upfront. But after this patch, only memory@0 node
for RMA is built upfront. Guest kernel boots with just that and rest of
the memory nodes (via memory@XXX or ibm,dynamic-reconfiguration-memory)
are built when guest does ibm,client-architecture-support call.

Note: This patch needs a SLOF enhancement which is already part of
SLOF binary in QEMU.

Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2015-09-23 10:51:10 +10:00
Markus Armbruster 1a9a507b2e qapi-introspect: Hide type names
To eliminate the temptation for clients to look up types by name
(which are not ABI), replace all type names by meaningless strings.

Reduces output of query-schema by 13 out of 85KiB.

As a debugging aid, provide option -u to suppress the hiding.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1442401589-24189-27-git-send-email-armbru@redhat.com>
2015-09-21 09:56:49 +02:00
Markus Armbruster 39a1815816 qapi: New QMP command query-qmp-schema for QMP introspection
qapi/introspect.json defines the introspection schema.  It's designed
for QMP introspection, but should do for similar uses, such as QGA.

The introspection schema does not reflect all the rules and
restrictions that apply to QAPI schemata.  A valid QAPI schema has an
introspection value conforming to the introspection schema, but the
converse is not true.

Introspection lowers away a number of schema details, and makes
implicit things explicit:

* The built-in types are declared with their JSON type.

  All integer types are mapped to 'int', because how many bits we use
  internally is an implementation detail.  It could be pressed into
  external interface service as very approximate range information,
  but that's a bad idea.  If we need range information, we better do
  it properly.

* Implicit type definitions are made explicit, and given
  auto-generated names:

  - Array types, named by appending "List" to the name of their
    element type, like in generated C.

  - The enumeration types implicitly defined by simple union types,
    named by appending "Kind" to the name of their simple union type,
    like in generated C.

  - Types that don't occur in generated C.  Their names start with ':'
    so they don't clash with the user's names.

* All type references are by name.

* The struct and union types are generalized into an object type.

* Base types are flattened.

* Commands take a single argument and return a single result.

  Dictionary argument or list result is an implicit type definition.

  The empty object type is used when a command takes no arguments or
  produces no results.

  The argument is always of object type, but the introspection schema
  doesn't reflect that.

  The 'gen': false directive is omitted as implementation detail.

  The 'success-response' directive is omitted as well for now, even
  though it's not an implementation detail, because it's not used by
  QMP.

* Events carry a single data value.

  Implicit type definition and empty object type use, just like for
  commands.

  The value is of object type, but the introspection schema doesn't
  reflect that.

* Types not used by commands or events are omitted.

  Indirect use counts as use.

* Optional members have a default, which can only be null right now

  Instead of a mandatory "optional" flag, we have an optional default.
  No default means mandatory, default null means optional without
  default value.  Non-null is available for optional with default
  (possible future extension).

* Clients should *not* look up types by name, because type names are
  not ABI.  Look up the command or event you're interested in, then
  follow the references.

  TODO Should we hide the type names to eliminate the temptation?

New generator scripts/qapi-introspect.py computes an introspection
value for its input, and generates a C variable holding it.

It can generate awfully long lines.  Marked TODO.

A new test-qmp-input-visitor test case feeds its result for both
tests/qapi-schema/qapi-schema-test.json and qapi-schema.json to a
QmpInputVisitor to verify it actually conforms to the schema.

New QMP command query-qmp-schema takes its return value from that
variable.  Its reply is some 85KiBytes for me right now.

If this turns out to be too much, we have a couple of options:

* We can use shorter names in the JSON.  Not the QMP style.

* Optionally return the sub-schema for commands and events given as
  arguments.

  Right now qmp_query_schema() sends the string literal computed by
  qmp-introspect.py.  To compute sub-schema at run time, we'd have to
  duplicate parts of qapi-introspect.py in C.  Unattractive.

* Let clients cache the output of query-qmp-schema.

  It changes only on QEMU upgrades, i.e. rarely.  Provide a command
  query-qmp-schema-hash.  Clients can have a cache indexed by hash,
  and re-query the schema only when they don't have it cached.  Even
  simpler: put the hash in the QMP greeting.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-21 09:56:49 +02:00
Markus Armbruster 2d21291ae6 qapi: Pseudo-type '**' is now unused, drop it
'gen': false needs to stay for now, because netdev_add is still using
it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1442401589-24189-25-git-send-email-armbru@redhat.com>
2015-09-21 09:56:49 +02:00
Markus Armbruster b8a98326d5 qapi-schema: Fix up misleading specification of netdev_add
It doesn't take a 'props' argument, let alone one in the format
"NAME=VALUE,..."

The bogus arguments specification doesn't matter due to 'gen': false.
Clean it up to be incomplete rather than wrong, and document the
incompleteness.

While there, improve netdev_add usage example in the manual: add a
device option to show how it's done.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1442401589-24189-24-git-send-email-armbru@redhat.com>
2015-09-21 09:56:49 +02:00
Markus Armbruster 28770e057f qapi: Introduce a first class 'any' type
It's first class, because unlike '**', it actually works, i.e. doesn't
require 'gen': false.

'**' will go away next.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
2015-09-21 09:56:49 +02:00
Markus Armbruster f133f2db1e qapi: Improve built-in type documentation
Clarify how they map to JSON.  Add how they map to C.  Fix the
reference to StringInputVisitor.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1442401589-24189-20-git-send-email-armbru@redhat.com>
2015-09-21 09:56:49 +02:00
Markus Armbruster 56d92b003a qapi-commands: De-duplicate output marshaling functions
gen_marshal_output() uses its parameter name only for name of the
generated function.  Name it after the type being marshaled instead of
its caller, and drop duplicates.

Saves 7 copies of qmp_marshal_output_int() in qemu-ga, and one copy of
qmp_marshal_output_str() in qemu-system-*.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1442401589-24189-19-git-send-email-armbru@redhat.com>
2015-09-21 09:56:48 +02:00
Markus Armbruster 7fad30f06e qapi: Rename qmp_marshal_input_FOO() to qmp_marshal_FOO()
These functions marshal both input and output.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1442401589-24189-17-git-send-email-armbru@redhat.com>
2015-09-21 09:56:48 +02:00
Markus Armbruster e98859a9b9 qapi: Clean up after recent conversions to QAPISchemaVisitor
Generate just 'FOO' instead of 'struct FOO' when possible.

Drop helper functions that are now unused.

Make pep8 and pylint reasonably happy.

Rename generate_FOO() functions to gen_FOO() for consistency.

Use more consistent and sensible variable names.

Consistently use c_ for mapping keys when their value is a C
identifier or type.

Simplify gen_enum() and gen_visit_union()

Consistently use single quotes for C text string literals.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1442401589-24189-14-git-send-email-armbru@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-21 09:56:48 +02:00
Markus Armbruster efd2eaa6c2 qapi: De-duplicate enum code generation
Duplicated in commit 21cd70d.  Yes, we can't import qapi-types, but
that's no excuse.  Move the helpers from qapi-types.py to qapi.py, and
replace the duplicates in qapi-event.py.

The generated event enumeration type's lookup table becomes
const-correct (see commit 2e4450f), and uses explicit indexes instead
of relying on order (see commit 912ae9c).

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1442401589-24189-10-git-send-email-armbru@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-21 09:56:47 +02:00
Markus Armbruster 2b162ccbe8 qapi-types: Convert to QAPISchemaVisitor, fixing flat unions
Fixes flat unions to get the base's base members.  Test case is from
commit 2fc0043, in qapi-schema-test.json:

    { 'union': 'UserDefFlatUnion',
      'base': 'UserDefUnionBase',
      'discriminator': 'enum1',
      'data': { 'value1' : 'UserDefA',
                'value2' : 'UserDefB',
                'value3' : 'UserDefB' } }

    { 'struct': 'UserDefUnionBase',
      'base': 'UserDefZero',
      'data': { 'string': 'str', 'enum1': 'EnumOne' } }

    { 'struct': 'UserDefZero',
      'data': { 'integer': 'int' } }

Patch's effect on UserDefFlatUnion:

     struct UserDefFlatUnion {
         /* Members inherited from UserDefUnionBase: */
    +    int64_t integer;
         char *string;
         EnumOne enum1;
         /* Own members: */
         union { /* union tag is @enum1 */
             void *data;
             UserDefA *value1;
             UserDefB *value2;
             UserDefB *value3;
         };
     };

Flat union visitors remain broken.  They'll be fixed next.

Code is generated in a different order now, but that doesn't matter.

The two guards QAPI_TYPES_BUILTIN_STRUCT_DECL and
QAPI_TYPES_BUILTIN_CLEANUP_DECL are replaced by just
QAPI_TYPES_BUILTIN.

Two ugly special cases for simple unions now stand out like sore
thumbs:

1. The type tag is named 'type' everywhere, except in generated C,
   where it's 'kind'.

2. QAPISchema lowers simple unions to semantically equivalent flat
   unions.  However, the C generated for a simple unions differs from
   the C generated for its equivalent flat union, and we therefore
   need special code to preserve that pointless difference for now.

Mark both TODO.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-21 09:53:16 +02:00
Daniel P. Berrange 351d36e454 qapi: allow override of default enum prefix naming
The camel_to_upper() method applies some heuristics to turn
a mixed case type name into an all-uppercase name. This is
used for example, to generate enum constant name prefixes.

The heuristics don't also generate a satisfactory name
though. eg

  { 'enum': 'QCryptoTLSCredsEndpoint',
    'data': ['client', 'server']}

Results in Q_CRYPTOTLS_CREDS_ENDPOINT_CLIENT. This has
an undesirable _ after the initial Q and is missing an
_ between the CRYPTO & TLS strings.

Rather than try to add more and more heuristics to try
to cope with this, simply allow the QAPI schema to
specify the desired enum constant prefix explicitly.

eg

  { 'enum': 'QCryptoTLSCredsEndpoint',
    'prefix': 'QCRYPTO_TLS_CREDS_ENDPOINT',
    'data': ['client', 'server']}

Now gives the QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT name.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-09-15 10:59:28 +01:00
Veres Lajos 67cc32ebfd typofixes - v4
Signed-off-by: Veres Lajos <vlajos@gmail.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-09-11 10:45:43 +03:00
Daniel P. Berrange b6af097528 maint: remove / fix many doubled words
Many source files have doubled words (eg "the the", "to to",
and so on). Most of these can simply be removed, but a couple
were actual mis-spellings (eg "to to" instead of "to do").
There was even one triple word score "to to to" :-)

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-09-11 10:21:38 +03:00
Alberto Garcia 7f65ce834a docs: document how to configure the qcow2 L2/refcount caches
QEMU has options to configure the size of the L2 and refcount
caches for the qcow2 format. However, choosing the right sizes for
a particular disk image is not a straightforward operation since
the ratio between the cache size and the allocated disk space is
not obvious and depends on the size of the cluster and the refcount
entries.

This document attempts to give an overview of both caches and how to
configure their sizes.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 55de928e139b1ba3f3d40fe9c6c88f30b1f36410.1438690126.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-09-04 21:00:32 +02:00