Detect all invalid configurations (e.g. mingw32 with vhost-user,
non-Linux with vhost-kernel).  As a collateral benefit, all vhost-kernel
backends can be now disabled if one wants to reduce the attack surface.
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NThomas Huth <thuth@redhat.com>
Message-Id: <1543851204-41186-6-git-send-email-pbonzini@redhat.com>
Message-Id: <1550165756-21617-7-git-send-email-pbonzini@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

This shows a preexisting bug: if a KVM target did not have virtio-net enabled,
it would fail with undefined symbols when vhost was enabled.  This must now
be fixed, lest targets that have no virtio-net fail to compile.
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NThomas Huth <thuth@redhat.com>
Message-Id: <1543851204-41186-5-git-send-email-pbonzini@redhat.com>
Message-Id: <1550165756-21617-6-git-send-email-pbonzini@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

vhost-user already has a way to communicate the endianness of the guest
via the vring endianness messages.  The vring endianness always matches
the vnet header endianness so there is no need to do anything else in
the backend.
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-Id: <1543851204-41186-9-git-send-email-pbonzini@redhat.com>
Message-Id: <1550165756-21617-5-git-send-email-pbonzini@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

vhost-user does not depend on Linux; it can run on any POSIX system.  Restrict
vhost-kernel to Linux in hw/virtio/vhost-backend.c, everything else can be
compiled on all POSIX systems.
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: NThomas Huth <thuth@redhat.com>
Message-Id: <1543851204-41186-4-git-send-email-pbonzini@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-Id: <1550165756-21617-4-git-send-email-pbonzini@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

hw/net/vhost_net.c needs functions that are declared in net/vhost-user.c: the
vhost-user code is always compiled into QEMU, only the constructor
net_init_vhost_user is unreachable.  Also, net/vhost-user.c needs functions
declared in hw/virtio/vhost-stub.c even if no virtio device exists.

Break this dependency.  First, add a minimal version of net/vhost-user.c,
with no functionality and no dependency on vhost code.  Second, #ifdef out
the calls back to net/vhost-user.c from hw/net/vhost_net.c.

While at it, this patch fixes the CONFIG_VHOST_NET_USE*D* typo.
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <1543851204-41186-3-git-send-email-pbonzini@redhat.com>
Reviewed-by: NThomas Huth <thuth@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-Id: <1550165756-21617-3-git-send-email-pbonzini@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

There is no reason for CONFIG_VHOST_NET to be specific to a single target;
it is a host feature that can be add to all targets, as long as they support
the virtio-net device.  Currently CONFIG_VHOST_NET depends on CONFIG_KVM,
but ioeventfd support is present in the core memory API and works with
other accelerators as well.

As a first step, move the vhost-net stubs to a separate file.  Later, they
will become conditional on CONFIG_VIRTIO_NET, which is not available in .c
files.
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: NThomas Huth <thuth@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-Id: <1543851204-41186-2-git-send-email-pbonzini@redhat.com>
Message-Id: <1550165756-21617-2-git-send-email-pbonzini@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Pull request

# gpg: Signature made Wed 20 Feb 2019 18:01:00 GMT
# 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:
  blockdev: acquire aio_context for bitmap add/remove
  block/dirty-bitmap: Documentation and Comment fixups
  dirty-bitmap: Expose persistent flag to 'query-block'
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

usb: usb_ep_get() fixes

# gpg: Signature made Wed 20 Feb 2019 11:13:32 GMT
# gpg:                using RSA key 4CB6D8EED3E87138
# 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/usb-20190220-pull-request:
  usb: remove unnecessary NULL device check from usb_ep_get()
  usb: add device checks before redirector calls to usb_ep_get()
  usb: check device is not NULL before calling usb_ep_get()
  uhci: check device is not NULL before calling usb_ep_get()
  ohci: check device is not NULL before calling usb_ep_get()
  ehci: check device is not NULL before calling usb_ep_get()
  xhci: check device is not NULL before calling usb_ep_get()
  xhci: add asserts to help with static code analysis
  usb: rearrange usb_ep_get()
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

No caller of usb_ep_get() calls it with a NULL device (previous commits
have addressed the few remaining cases which didn't explicitly check).
Replace check for 'dev == NULL' with an assert instead.
Signed-off-by: NLiam Merwick <liam.merwick@oracle.com>
Message-id: 1549460216-25808-10-git-send-email-liam.merwick@oracle.com
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

Add an assert and an explicit check before the two callers to
usb_ep_get() in the USB redirector code to ensure the device
passed in is not NULL.
Signed-off-by: NLiam Merwick <liam.merwick@oracle.com>
Message-id: 1549460216-25808-9-git-send-email-liam.merwick@oracle.com
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

In musb_packet(), the call to usb_find_device() can return NULL
if it doesn't find a device matching 'addr' so explicitly check
the return value before passing it to usb_ep_get().  This then
allows the subsequent calculation of 'id' to be streamlined.
Signed-off-by: NLiam Merwick <liam.merwick@oracle.com>
Message-id: 1549460216-25808-8-git-send-email-liam.merwick@oracle.com
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

In uhci_handle_td(), the call to ehci_find_device() can return NULL
if it doesn't find a device matching 'addr' so explicitly check
the return value before passing it to usb_ep_get().
Signed-off-by: NLiam Merwick <liam.merwick@oracle.com>
Message-id: 1549460216-25808-7-git-send-email-liam.merwick@oracle.com
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

A call to ohci_find_device() can return NULL if it doesn't find a
device matching 'addr' so for the two callers, explicitly check
the return value before passing it to usb_ep_get().
Signed-off-by: NLiam Merwick <liam.merwick@oracle.com>
Message-id: 1549460216-25808-6-git-send-email-liam.merwick@oracle.com
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

In ehci_process_itd(), the call to ehci_find_device() can return NULL
if it doesn't find a device matching 'devaddr' so explicitly check
the return value before passing it to usb_ep_get().
Signed-off-by: NLiam Merwick <liam.merwick@oracle.com>
Message-id: 1549460216-25808-5-git-send-email-liam.merwick@oracle.com
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

Signed-off-by: NLiam Merwick <liam.merwick@oracle.com>
Message-id: 1549460216-25808-4-git-send-email-liam.merwick@oracle.com
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

Most callers of xhci_port_update() and xhci_wakeup() pass in a pointer
to an array entry and can never be NULL but add two defensive asserts
to protect against future changes (e.g. adding a new port speed, etc.)
adding a path through xhci_lookup_port() that could result in the
return of a NULL XHCIPort.
Signed-off-by: NLiam Merwick <liam.merwick@oracle.com>
Message-id: 1549460216-25808-3-git-send-email-liam.merwick@oracle.com
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

There is no need to calculate the 'eps' variable in usb_ep_get()
if 'ep' is the control endpoint.  Instead the calculation should
be done after validating the input before returning an entry
indexed by the endpoint 'ep'.
Signed-off-by: NLiam Merwick <liam.merwick@oracle.com>
Reviewed-by: NDarren Kenny <Darren.Kenny@oracle.com>
Reviewed-by: NMark Kanda <Mark.Kanda@oracle.com>
Reviewed-by: NAmeya More <ameya.more@oracle.com>
Message-id: 1549460216-25808-2-git-send-email-liam.merwick@oracle.com
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

When bitmaps are persistent, they may incur a disk read or write when bitmaps
are added or removed. For configurations like virtio-dataplane, failing to
acquire this lock will abort QEMU when disk IO occurs.

We used to acquire aio_context as part of the bitmap lookup, so re-introduce
the lock for just the cases that have an IO penalty. Commit 2119882c removed
these locks, and I failed to notice this when we committed fd5ae4cc, so this
has been broken since persistent bitmaps were introduced.

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1672010Reported-By: NAihua Liang <aliang@redhat.com>
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-id: 20190218233154.19303-1-jsnow@redhat.com
Signed-off-by: NJohn Snow <jsnow@redhat.com>

The meaning of the states has changed subtly over time,
this should bring the understanding more in-line with the
current, actual usages.
Reported-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190202011048.12343-1-jsnow@redhat.com
Signed-off-by: NJohn Snow <jsnow@redhat.com>

Since qemu currently doesn't flush persistent bitmaps to disk until
shutdown (which might be MUCH later), it's useful if 'query-block'
at least shows WHICH bitmaps will (eventually) make it to persistent
storage.  Update affected iotests.
Signed-off-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Message-id: 20190204210512.27458-1-eblake@redhat.com
Signed-off-by: NJohn Snow <jsnow@redhat.com>

ppc patch queue 2019-02-19

Here's the next batch of ppc and spapr patches.  Higlights are:

 * A bunch of improvements to TCG handling of vector instructions from
   Richard Henderson and Marc Cave-Ayland

 * Cleanup to the XICS interrupt controller from Greg Kurz, removing
   the special KVM subclasses which were a bad idea

 * Some refinements to the XIVE interrupt controller from Cédric Le
   Goater

 * Fix from Fabiano Rosas for a really dumb buffer overflow in the
   device tree code for memory hotplug

 * Code for allowing access to SPRs from the gdb stub from Fabiano
   Rosas

 * Assorted minor fixes and cleanups

# gpg: Signature made Mon 18 Feb 2019 13:47:54 GMT
# gpg:                using RSA key 75F46586AE61A66CC44E87DC6C38CACA20D9B392
# gpg: Good signature from "David Gibson <david@gibson.dropbear.id.au>" [full]
# gpg:                 aka "David Gibson (Red Hat) <dgibson@redhat.com>" [full]
# gpg:                 aka "David Gibson (ozlabs.org) <dgibson@ozlabs.org>" [full]
# gpg:                 aka "David Gibson (kernel.org) <dwg@kernel.org>" [unknown]
# Primary key fingerprint: 75F4 6586 AE61 A66C C44E  87DC 6C38 CACA 20D9 B392

* remotes/dgibson/tags/ppc-for-4.0-20190219: (43 commits)
  target/ppc: convert vmin* and vmax* to vector operations
  target/ppc: convert vadd*s and vsub*s to vector operations
  target/ppc: Split out VSCR_SAT to a vector field
  target/ppc: Add set_vscr_sat
  target/ppc: Use mtvscr/mfvscr for vmstate
  target/ppc: Add helper_mfvscr
  target/ppc: Remove vscr_nj and vscr_sat
  target/ppc: Use helper_mtvscr for reset and gdb
  target/ppc: Pass integer to helper_mtvscr
  target/ppc: convert xxsel to vector operations
  target/ppc: convert xxspltw to vector operations
  target/ppc: convert xxspltib to vector operations
  target/ppc: convert VSX logical operations to vector operations
  target/ppc: convert vsplt[bhw] to use vector operations
  target/ppc: convert vspltis[bhw] to use vector operations
  target/ppc: convert vaddu[b,h,w,d] and vsubu[b,h,w,d] over to use vector operations
  target/ppc: convert VMX logical instructions to use vector operations
  xics: Drop the KVM ICS class
  spapr/irq: Use the "simple" ICS class for KVM
  xics: Handle KVM interrupt presentation from "simple" ICS code
  ...
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

QAPI patches for 2019-02-18

# gpg: Signature made Mon 18 Feb 2019 13:44:30 GMT
# gpg:                using RSA key 3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>" [full]
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>" [full]
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-qapi-2019-02-18:
  qapi: move RTC_CHANGE to the target schema
  qmp: Deprecate query-events in favor of query-qmp-schema
  Revert "qapi-events: add 'if' condition to implicit event enum"
  qapi: remove qmp_unregister_command()
  qapi: make query-cpu-definitions depend on specific targets
  qapi: make query-cpu-model-expansion depend on s390 or x86
  qapi: make query-gic-capabilities depend on TARGET_ARM
  target.json: add a note about query-cpu* not being s390x-specific
  qapi: make s390 commands depend on TARGET_S390X
  qapi: make rtc-reset-reinjection and SEV depend on TARGET_I386
  qapi: New module target.json
  build: Deal with all of QAPI's .o in qapi/Makefile.objs
  build-sys: move qmp-introspect per target
  qapi: Generate QAPIEvent stuff into separate files
  qapi: Prepare for system modules other than 'builtin'
  qapi: Clean up modular built-in code generation a bit
  qapi: Fix up documentation for recent commit a9529100
  qapi: Belatedly document modular code generation
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

A few targets don't emit RTC_CHANGE, we could restrict the event to
the tagets that do emit it.

Note: There is a lot more of events & commands that we could restrict
to capable targets, with the cost of some additional complexity, but
the benefit of added correctness and better introspection.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20190214152251.2073-19-armbru@redhat.com>

query-events doesn't reflect compile-time configuration.  Instead of
fixing that, deprecate the command in favor of query-qmp-schema.

Libvirt prefers query-qmp-schema as of commit 22d7222ec0 "qemu: caps:
Don't call 'query-events' when we probe events from QMP schema".
It'll be in the next release.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190214152251.2073-18-armbru@redhat.com>

This reverts commit 7bd26349.

The commit applied the events' conditions to the members of enum
QAPIEvent.  Awkward, because it renders QAPIEvent unusable in
target-independent code as soon as we make an event target-dependent.
Reverting this has the following effects:

* ui/vnc.c can remain target independent.

* monitor_qapi_event_conf[] doesn't have to muck around with #ifdef.

* query-events again doesn't reflect conditionals.  I'm going to
  deprecate it in favor of query-qmp-schema.

Another option would be to split target-dependent parts off enum
QAPIEvent into a target-dependent enum.  Doesn't seem worthwhile right
now.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190214152251.2073-17-armbru@redhat.com>

This command is no longer needed, the schema has compile-time
configuration conditions.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20190214152251.2073-16-armbru@redhat.com>

It depends on TARGET_PPC || TARGET_ARM || TARGET_I386 || TARGET_S390X.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NEduardo Habkost <ehabkost@redhat.com>
Acked-by: NCornelia Huck <cohuck@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20190214152251.2073-15-armbru@redhat.com>

Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NEduardo Habkost <ehabkost@redhat.com>
Acked-by: NCornelia Huck <cohuck@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20190214152251.2073-14-armbru@redhat.com>

Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20190214152251.2073-13-armbru@redhat.com>

Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: NCornelia Huck <cohuck@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20190214152251.2073-12-armbru@redhat.com>

Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: NCornelia Huck <cohuck@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20190214152251.2073-11-armbru@redhat.com>

Move rtc-reset-reinjection and SEV in target.json and make them
conditional on TARGET_I386.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20190214152251.2073-10-armbru@redhat.com>

We can't add appropriate target-specific conditionals to misc.json,
because that would make all of misc.json unusable in
target-independent code.  To keep misc.json target-independent, we
need to split off target-dependent target.json.

This commit doesn't actually split off anything, it merely creates the
empty module.  The next few patches will move stuff from misc.json
there.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190214152251.2073-9-armbru@redhat.com>

Adding QAPI's .o to util-obj-y, common-obj-y and obj-y is spread over
three places: Makefile.objs takes care of target-independent generated
code, Makefile.target of target-dependent generated code, and
qapi/Makefile.objs of (target-independent) hand-written code.

Do everything in qapi/Makefile.objs.
Suggested-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190214152251.2073-8-armbru@redhat.com>

The following patches are going to introduce per-target #ifdef in the
schemas.

The introspection data is statically generated once, and must thus be
built per-target to reflect target-specific configuration.

Drop "do_test_visitor_in_qmp_introspect(&qmp_schema_qlit)" since the
schema is no longer in a common object. It is covered by the per-target
query-qmp-schema test instead.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20190214152251.2073-7-armbru@redhat.com>

Having to include qapi-events.h just for QAPIEvent is suboptimal, but
quite tolerable now.  It'll become problematic when we have events
conditional on the target, because then qapi-events.h won't be usable
from target-independent code anymore.  Avoid that by generating it
into separate files.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190214152251.2073-6-armbru@redhat.com>

The next commit wants to generate qapi-emit-events.{c.h}.  To enable
that, extend QAPISchemaModularCVisitor to support additional "system
modules", i.e. modules that don't correspond to a (user-defined) QAPI
schema module.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190214152251.2073-5-armbru@redhat.com>

We neglect to call .visit_module() for the special module we use for
built-ins.  Harmless, but clean it up anyway.  The
tests/qapi-schema/*.out now show the built-in module as 'module None'.

Subclasses of QAPISchemaModularCVisitor need to ._add_module() this
special module to enable code generation for built-ins.  When this
hasn't been done, QAPISchemaModularCVisitor.visit_module() does
nothing for the special module.  That looks like built-ins could
accidentally be generated into the wrong module when a subclass
neglects to call ._add_module().  Can't happen, because built-ins are
all visited before any other module.  But that's non-obvious.  Switch
off code generation explicitly.

Rename QAPISchemaModularCVisitor._begin_module() to
._begin_user_module().

New QAPISchemaModularCVisitor._is_builtin_module(), for clarity.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190214152251.2073-4-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190214152251.2073-3-armbru@redhat.com>

We generate code for built-ins and sub-modules into separate files
since commit cdb6610a and 252dc310 (v2.12.0).  Both commits
neglected to update documentation.  Do that now.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190214152251.2073-2-armbru@redhat.com>