A number of the channel implementations will require the
ability to create watches on file descriptors / sockets.
To avoid duplicating this code in each channel, provide a
helper API for dealing with file descriptor watches.

There are two watch implementations provided. The first
is useful for bi-directional file descriptors such as
sockets, regular files, character devices, etc. The
second works with a pair of unidirectional file descriptors
such as pipes.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

Start the new generic I/O channel framework by defining a
QIOChannel abstract base class. This is designed to feel
similar to GLib's GIOChannel, but with the addition of
support for using iovecs, qemu error reporting, file
descriptor passing, coroutine integration and use of
the QOM framework for easier sub-classing.

The intention is that anywhere in QEMU that almost
anywhere that deals with sockets will use this new I/O
infrastructure, so that it becomes trivial to then layer
in support for TLS encryption. This will at least include
the VNC server, char device backend and migration code.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

* KVM: synic support, split irqchip support
* memory: cleanups, optimizations, ioeventfd emulation
* SCSI: small fixes, vmw_pvscsi compatibility improvements
* qemu_log cleanups
* Coverity model improvements

# gpg: Signature made Thu 17 Dec 2015 16:35:21 GMT 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: (45 commits)
  coverity: Model g_memdup()
  coverity: Model g_poll()
  scsi: always call notifier on async cancellation
  scsi: use scsi_req_cancel_async when purging requests
  target-i386: kvm: clear unusable segments' flags in migration
  rcu: optimize rcu_read_lock
  memory: try to inline constant-length reads
  memory: inline a few small accessors
  memory: extract first iteration of address_space_read and address_space_write
  memory: split address_space_read and address_space_write
  memory: avoid unnecessary object_ref/unref
  memory: reorder MemoryRegion fields
  exec: make qemu_ram_ptr_length more similar to qemu_get_ram_ptr
  exec: always call qemu_get_ram_ptr within rcu_read_lock
  linux-user: convert DEBUG_SIGNAL logging to tracepoints
  linux-user: avoid "naked" qemu_log
  user: introduce "-d page"
  xtensa: avoid "naked" qemu_log
  tricore: avoid "naked" qemu_log
  ppc: cleanup logging
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

We model all the non-deprecated memory allocation functions from
https://developer.gnome.org/glib/stable/glib-Memory-Allocation.html


except for g_memdup(), g_clear_pointer(), g_steal_pointer().  We don't
use the latter two.  Model the former.

Coverity now reports an OVERRUN
vl.c:2317: alloc_strlen: Allocating insufficient memory for the terminating null of the string.
Correct, but we omit the terminating null intentionally there.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1448901152-11716-1-git-send-email-armbru@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

In my testing, Coverity reported two more CHECKED_RETURN:

* qemu-char.c:1248: fixed in commit c1f24489: "qemu-char: retry g_poll
  on EINTR".

* migration/qemu-file-unix.c:75: harmless, cleaned up in commit
  4e39f57c "migration: Clean up use of g_poll() in
  socket_writev_buffer()

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1450336833-27710-1-git-send-email-armbru@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

This was found by code inspection.  If the request is cancelled twice,
the notifier is never called on the second cancellation request,
and hence for example a TMF might never finish.

All the calls in scsi_req_cancel_async are idempotent, so the change
is safe.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1450290827-30508-2-git-send-email-pbonzini@redhat.com>

This avoids calls to aio_poll without having acquired the context first.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1450290827-30508-1-git-send-email-pbonzini@redhat.com>

This commit fixes migration of a QEMU/KVM guest from kernel >= v3.9 to
kernel <= v3.7 (e.g. from RHEL 7 to RHEL 6). Without this commit a guest
migrated across these kernel versions fails to resume on the target host
as its segment descriptors are invalid.

Two separate kernel commits combined together to result in this bug:

  commit f0495f9b9992f80f82b14306946444b287193390
  Author: Avi Kivity <avi@redhat.com>
  Date:   Thu Jun 7 17:06:10 2012 +0300

      KVM: VMX: Relax check on unusable segment

      Some userspace (e.g. QEMU 1.1) munge the d and g bits of segment
      descriptors, causing us not to recognize them as unusable segments
      with emulate_invalid_guest_state=1.  Relax the check by testing for
      segment not present (a non-present segment cannot be usable).

Signed-off-by: Avi Kivity <avi@redhat.com>

  commit 25391454e73e3156202264eb3c473825afe4bc94
  Author: Gleb Natapov <gleb@redhat.com>
  Date:   Mon Jan 21 15:36:46 2013 +0200

      KVM: VMX: don't clobber segment AR of unusable segments.

      Usability is returned in unusable field, so not need to clobber entire
      AR. Callers have to know how to deal with unusable segments already
      since if emulate_invalid_guest_state=true AR is not zeroed.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

The first commit changed the KVM_SET_SREGS ioctl so that it did no treat
segment flags == 0 as an unusable segment, instead only looking at the
"present" flag.

The second commit changed KVM_GET_SREGS so that it did not clear the
flags of an unusable segment.

Since QEMU does not itself maintain the "unusable" flag across a
migration, the end result is that unusable segments read from a kernel
with these commits and loaded into a kernel without these commits are
not properly recognised as being unusable.

This commit updates both get_seg and set_seg so that the problem is
avoided even when migrating to or migrating from a QEMU without this
commit. In get_seg, we clear the segment flags if the segment is marked
unusable. In set_seg, we mark the segment unusable if the segment's
"present" flag is not set.

Signed-off-by: Michael Chapman <mike@very.puzzling.org>
Message-Id: <1449464047-17467-1-git-send-email-mike@very.puzzling.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

rcu_read_lock cannot change rcu_gp_ongoing from true to false
(the previous value of p_rcu_reader->ctr is zero), hence
there is no need to check p_rcu_reader->waiting and wake up
a concurrent synchronize_rcu.

While at it mark the wakeup as unlikely in rcu_read_unlock.

Reviewed-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1450265542-4323-1-git-send-email-pbonzini@redhat.com>

memcpy can take a large amount of time for small reads and writes.
Handle the common case of reading s/g descriptors from memory (there
is no corresponding "write" case that is as common, because writes
often use address_space_st* functions) by inlining the relevant
parts of address_space_read into the caller.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

These are used in the address_space_* fast paths.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

We want to inline the case where there is only one iteration, because
then the compiler can also inline the memcpy.  As a start, extract
everything after the first address_space_translate call.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Rather than dispatching on is_write for every iteration, make
address_space_rw call one of the two functions.  The amount of
duplicate logic is pretty small, and memory_access_is_direct can
be tweaked so that it inlines better in the callers.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

For the common case of DMA into non-hotplugged RAM, it is unnecessary
but expensive to do object_ref/unref.  Add back an owner field to
MemoryRegion, so that these memory regions can skip the reference
counting.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Order fields so that all fields accessed during a RAM read/write fit in
the same cache line.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Notably, use qemu_get_ram_block to enjoy the MRU optimization.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Simplify the code and document the assumption.  The only caller
that is not within rcu_read_lock is memory_region_get_ram_ptr.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

"Unimplemented" messages go to stderr, everything else goes to tracepoints

Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Ensure that all log writes are protected by qemu_loglevel_mask or,
in serious cases, go to both the log and stderr.

Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Cc: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Avoid "naked" qemu_log, bring documentation for DEBUG #defines
up to date.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Convert to debug-only qemu_log.

Cc: Alexander Graf <agraf@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

In some cases, the same message is printed both on stderr and in the log.
Avoid duplicate output in the default case where stderr _is_ the log,
and standardize this to stderr+log where it used to use stdio+log.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Our QA team wants to preserve serial output of the guest in between QEMU
runs to perform post-analysis.

By default this behavior is off (file is truncated each time QEMU is
started or device is plugged).

Signed-off-by: Olga Krishtal <okrishtal@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Eric Blake <eblake@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1449211324-17856-1-git-send-email-den@openvz.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

This patch adds support for split IRQ chip mode. When
KVM_CAP_SPLIT_IRQCHIP is enabled:

    1.) The PIC, PIT, and IOAPIC are implemented in userspace while
    the LAPIC is implemented by KVM.

    2.) The software IOAPIC delivers interrupts to the KVM LAPIC via
    kvm_set_irq. Interrupt delivery is configured via the MSI routing
    table, for which routes are reserved in target-i386/kvm.c then
    configured in hw/intc/ioapic.c

    3.) KVM delivers IOAPIC EOIs via a new exit KVM_EXIT_IOAPIC_EOI,
    which is handled in target-i386/kvm.c and relayed to the software
    IOAPIC via ioapic_eoi_broadcast.

Signed-off-by: Matt Gingell <gingell@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

This patch adds the initial plumbing for split IRQ chip mode via
KVM_CAP_SPLIT_IRQCHIP. In addition to option processing, a number of
kvm_*_in_kernel macros are defined to help clarify which component is
where.

Signed-off-by: Matt Gingell <gingell@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Hyper-V SynIC timers are host timers that are configurable
by guest through corresponding MSR's (HV_X64_MSR_STIMER*).
Guest setup and use fired by host events(SynIC interrupt
and appropriate timer expiration message) as guest clock
events.

The state of Hyper-V SynIC timers are stored in corresponding
MSR's. This patch seria implements such MSR's support and migration.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Eduardo Habkost <ehabkost@redhat.com>
CC: "Andreas Färber" <afaerber@suse.de>
CC: Marcelo Tosatti <mtosatti@redhat.com>
CC: Denis V. Lunev <den@openvz.org>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: kvm@vger.kernel.org

Message-Id: <1448464885-8300-3-git-send-email-asmetanin@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

'hyperv-testdev' will be used by kvm-unit-tests
to setup Hyper-V SynIC SINT's routing and to inject
Hyper-V SynIC SINT's.

Hyper-V test device is ISA type device that creates 0x3000
IO memory region and catches write access into it. Every
write operation data decoded into ctl code and parameters
for Hyper-V test device.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Eduardo Habkost <ehabkost@redhat.com>
CC: "Andreas Färber" <afaerber@suse.de>
CC: Marcelo Tosatti <mtosatti@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Hyper-V SynIC(synthetic interrupt controller) helpers for
Hyper-V SynIC irq routing setup, irq injection, irq ack
notifications event/message pages changes tracking for future use.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Eduardo Habkost <ehabkost@redhat.com>
CC: "Andreas Färber" <afaerber@suse.de>
CC: Marcelo Tosatti <mtosatti@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Eduardo Habkost <ehabkost@redhat.com>
CC: "Andreas Färber" <afaerber@suse.de>
CC: Marcelo Tosatti <mtosatti@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

This patch does Hyper-V Synthetic interrupt
controller(Hyper-V SynIC) MSR's support and
migration. Hyper-V SynIC is enabled by cpu's
'hv-synic' option.

This patch does not allow cpu creation if
'hv-synic' option specified but kernel
doesn't support Hyper-V SynIC.

Changes v3:
* removed 'msr_hv_synic_version' migration because
it's value always the same
* moved SynIC msr's initialization into kvm_arch_init_vcpu

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Eduardo Habkost <ehabkost@redhat.com>
CC: "Andreas Färber" <afaerber@suse.de>
CC: Marcelo Tosatti <mtosatti@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Following the previous patch which changed pvscsi to be a pci express
device, this patch introduces a boolean property 'x-disable-pcie'.

Its default value is false, exposing pvscsi as a pcie device.

Setting 'x-disable-pcie' to 'on' preserves the old 'pci device' (non
express) behavior. This allows migration to older versions.

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@ravellosystems.com>
Message-Id: <1449994112-7054-7-git-send-email-shmulik.ladkani@ravellosystems.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Report the 'express endpoint' capability if on a PCIE bus.

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@ravellosystems.com>
Message-Id: <1449994112-7054-6-git-send-email-shmulik.ladkani@ravellosystems.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Introduce a class type for pvscsi, and the usual
DEVICE_CLASS/DEVICE_GET_CLASS macros.

No semantic change.

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@ravellosystems.com>
Message-Id: <1449994112-7054-5-git-send-email-shmulik.ladkani@ravellosystems.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>