When passed the path to a binary we copy it and any linked libraries (if
it is dynamically linked) into the docker build context. These can then
be included by a dockerfile with the line:

  # Copy all of context into container
  ADD . /

This is mainly intended for setting up foreign architecture docker
images which use qemu-$arch to do cross-architecture linux-user
execution. It also relies on the host and guest file-system following
reasonable multi-arch layouts so the copied libraries don't clash with
the guest ones.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Message-id: 1468934445-32183-3-git-send-email-famz@redhat.com
Signed-off-by: NFam Zheng <famz@redhat.com>

Instead of letting the build_image create the temporary working dir we
move the creation to the build command. This is preparation for the
later patches where additional files can be added to the build context
before the build step is run.

We also ensure we remove the build context after we are done (mkdtemp
doesn't do this automatically for you).
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NFam Zheng <famz@redhat.com>
Message-id: 1468934445-32183-2-git-send-email-famz@redhat.com
Signed-off-by: NFam Zheng <famz@redhat.com>

disas/bfd.h defines ATTRIBUTE_UNUSED, but unfortunately the
ALSA system headers also define this macro, which means that
you can get a compilation failure if building with ALSA and
any files happen to include the alsa headers before bfd.h
rather than the other way around.

This is unfortunate namespace pollution by the ALSA headers but
we can work around it. Add an #ifndef guard to bfd.h and remove
the unnecessary extra definition in disas/arm.c to fix this.
Reported-by: NBALATON Zoltan <balaton@eik.bme.hu>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Message-id: 1468937076-21503-1-git-send-email-peter.maydell@linaro.org

* two old patches from prospective GSoC students
* i386 -kernel device tree support
* Coverity fix
* memory usage improvement from Peter
* checkpatch fix
* g_path_get_dirname cleanup
* caching of block status for iSCSI

# gpg: Signature made Tue 19 Jul 2016 07:43:41 BST
# gpg:                using RSA key 0xBFFBD25F78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini/tags/for-upstream:
  target-i386: Remove redundant HF_SOFTMMU_MASK
  block/iscsi: allow caching of the allocation map
  block/iscsi: fix rounding in iscsi_allocationmap_set
  Move README to markdown
  cpu-exec: Move down some declarations in cpu_exec()
  exec: avoid realloc in phys_map_node_reserve
  checkpatch: consider git extended headers valid patches
  megasas: remove useless check for cmd->frame
  compiler: never omit assertions if using a static analysis tool
  hw/i386: add device tree support
  Changed malloc to g_malloc, free to g_free in bsd-user/qemu.h
  use g_path_get_dirname instead of dirname
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Make IRC a little less noisy

# gpg: Signature made Mon 18 Jul 2016 16:42:57 BST
# gpg:                using RSA key 0xFBD0DB095A9E2A44
# gpg: Good signature from "Alex Bennée (Master Work Key) <alex.bennee@linaro.org>"
# Primary key fingerprint: 6685 AE99 E751 67BC AFC8  DF35 FBD0 DB09 5A9E 2A44

* remotes/stsquad/tags/pull-travis-20160718-1:
  .travis.yml: Disable IRC build status updates from forks
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

vnc: bugfixes for -rc0

# gpg: Signature made Tue 19 Jul 2016 08:27:05 BST
# gpg:                using RSA key 0x4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>"
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>"
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>"
# Primary key fingerprint: A032 8CFF B93A 17A7 9901  FE7D 4CB6 D8EE D3E8 7138

* remotes/kraxel/tags/pull-vnc-20160719-1:
  vnc-tight: fix regression with libxenstore
  vnc-enc-tight: fix off-by-one bug
  vnc: make sure we finish disconnect
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Update OpenBIOS images

# gpg: Signature made Tue 19 Jul 2016 07:42:30 BST
# gpg:                using RSA key 0x5BC2C56FAE0F321F
# gpg: Good signature from "Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>"
# Primary key fingerprint: CC62 1AB9 8E82 200D 915C  C9C4 5BC2 C56F AE0F 321F

* remotes/mcayland/tags/qemu-openbios-signed:
  Update OpenBIOS images to e79bca6 built from submodule.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

# gpg: Signature made Tue 19 Jul 2016 03:33:40 BST
# gpg:                using RSA key 0xEF04965B398D6211
# gpg: Good signature from "Jason Wang (Jason Wang on RedHat) <jasowang@redhat.com>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 215D 46F4 8246 689E C77F  3562 EF04 965B 398D 6211

* remotes/jasowang/tags/net-pull-request:
  e1000e: fix building without CONFIG_VMXNET3_PCI
  MAINTAINERS: release Scott from being a rocker maintainer
  tap: fix memory leak on failure to create a multiqueue tap device
  net: fix incorrect argument to iov_to_buf
  net: fix incorrect access to pointer
  e1000e: fix incorrect access to pointer
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

# gpg: Signature made Mon 18 Jul 2016 23:53:15 BST
# gpg:                using RSA key 0x7DEF8106AAFC390E
# gpg: Good signature from "John Snow (John Huston) <jsnow@redhat.com>"
# 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/ide-pull-request:
  block: ignore flush requests when storage is clean
  tests: in IDE and AHCI tests perform DMA write before flushing
  ide: set retry_unit for PIO and FLUSH requests
  ide: refactor retry_unit set and clear into separate function
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

# gpg: Signature made Mon 18 Jul 2016 22:59:55 BST
# gpg:                using RSA key 0x9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/tracing-pull-request:
  trace: Add QAPI/QMP interfaces to query and control per-vCPU tracing state
  trace: Allow event name pattern in "info trace-events"
  trace: Conditionally trace events based on their per-vCPU state
  trace: Add per-vCPU tracing states for events with the 'vcpu' property
  trace: Cosmetic changes on fast-path tracing
  disas: Remove unused macro '_'
  trace: Identify events with the 'vcpu' property
  trace: [bsd-user] Commandline arguments to control tracing
  trace: [linux-user] Commandline arguments to control tracing
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

VFIO update 2016-07-18

One fix for 2.7-rc0 which hides the ARI extended capability, fixing
multifunction support in PCIe configurations where the assigned device
function topology does not match the host (Alex Williamson)

# gpg: Signature made Mon 18 Jul 2016 18:02:27 BST
# gpg:                using RSA key 0x239B9B6E3BB08B22
# gpg: Good signature from "Alex Williamson <alex.williamson@redhat.com>"
# gpg:                 aka "Alex Williamson <alex@shazbot.org>"
# gpg:                 aka "Alex Williamson <alwillia@redhat.com>"
# gpg:                 aka "Alex Williamson <alex.l.williamson@gmail.com>"
# Primary key fingerprint: 42F6 C04E 540B D1A9 9E7B  8A90 239B 9B6E 3BB0 8B22

* remotes/awilliam/tags/vfio-update-20160718.0:
  vfio/pci: Hide ARI capability
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Signed-off-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

'HF_SOFTMMU_MASK' is only set when 'CONFIG_SOFTMMU' is defined. So
there's no need in this flag: test 'CONFIG_SOFTMMU' instead.
Suggested-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NSergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: NSergey Fedorov <sergey.fedorov@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Message-Id: <20160715175852.30749-6-sergey.fedorov@linaro.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

until now the allocation map was used only as a hint if a cluster
is allocated or not. If a block was not allocated (or Qemu had
no info about the allocation status) a get_block_status call was
issued to check the allocation status and possibly avoid
a subsequent read of unallocated sectors. If a block known to be
allocated the get_block_status call was omitted. In the other case
a get_block_status call was issued before every read to avoid
the necessity for a consistent allocation map. To avoid the
potential overhead of calling get_block_status for each and
every read request this took only place for the bigger requests.

This patch enhances this mechanism to cache the allocation
status and avoid calling get_block_status for blocks where
the allocation status has been queried before. This allows
for bypassing the read request even for smaller requests and
additionally omits calling get_block_status for known to be
unallocated blocks.
Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-Id: <1468831940-15556-3-git-send-email-pl@kamp.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

when setting clusters as alloacted the boundaries have
to be expanded. As Paolo pointed out the calculation of
the number of clusters is wrong:

Suppose cluster_sectors is 2, sector_num = 1, nb_sectors = 6:

In the "mark allocated" case, you want to set 0..8, i.e.
cluster_num=0, nb_clusters=4.

   0--.--2--.--4--.--6--.--8
   <--|_________________|-->  (<--> = expanded)

Instead you are setting nb_clusters=3, so that 6..8 is not marked.

   0--.--2--.--4--.--6--.--8
   <--|______________|!!!     (! = wrong)

Cc: qemu-stable@nongnu.org
Reported-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-Id: <1468831940-15556-2-git-send-email-pl@kamp.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Move the README file to markdown so that it makes the github page look
prettier. I know that github repo is a mirror and not the official
repo, but I think it doesn't hurt to have it in markdown format.
Signed-off-by: NPranith Kumar <bobby.prani@gmail.com>
Message-Id: <20160715043111.29007-1-bobby.prani@gmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Some guests (win2008 server for example) do a lot of unnecessary
flushing when underlying media has not changed. This adds additional
overhead on host when calling fsync/fdatasync.

This change introduces a write generation scheme in BlockDriverState.
Current write generation is checked against last flushed generation to
avoid unnessesary flushes.

The problem with excessive flushing was found by a performance test
which does parallel directory tree creation (from 2 processes).
Results improved from 0.424 loops/sec to 0.432 loops/sec.
Each loop creates 10^3 directories with 10 files in each.

This affected some blkdebug testcases that were expecting error logs from
failure-injected flushes which are now skipped entirely
(tests 026 071 089).

This also affects the performance of block jobs and thus BLOCK_JOB_READY
events for driver-mirror and active block-commit commands now arrives
faster, before QMP send successfully returns to caller (tests 141 144).
Signed-off-by: NEvgeny Yakovlev <eyakovlev@virtuozzo.com>
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1468870792-7411-5-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Fam Zheng <famz@redhat.com>
CC: John Snow <jsnow@redhat.com>
Signed-off-by: NJohn Snow <jsnow@redhat.com>

Due to changes in flush behaviour clean disks stopped generating
flush_to_disk events and IDE and AHCI tests that test flush commands
started to fail.

This change adds additional DMA writes to affected tests before sending
flush commands so that bdrv_flush actually generates flush_to_disk event.
Signed-off-by: NEvgeny Yakovlev <eyakovlev@virtuozzo.com>
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1468870792-7411-4-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Fam Zheng <famz@redhat.com>
CC: John Snow <jsnow@redhat.com>
Signed-off-by: NJohn Snow <jsnow@redhat.com>

The following sequence of tests discovered a problem in IDE emulation:
1. Send DMA write to IDE device 0
2. Send CMD_FLUSH_CACHE to same IDE device which will be failed by block
layer using blkdebug script in tests/ide-test:test_retry_flush

When doing DMA request ide/core.c will set s->retry_unit to s->unit in
ide_start_dma. When dma completes ide_set_inactive sets retry_unit to -1.
After that ide_flush_cache runs and fails thanks to blkdebug.
ide_flush_cb calls ide_handle_rw_error which asserts that s->retry_unit
== s->unit. But s->retry_unit is still -1 after previous DMA completion
and flush does not use anything related to retry.

This patch restricts retry unit assertion only to ops that actually use
retry logic.
Signed-off-by: NEvgeny Yakovlev <eyakovlev@virtuozzo.com>
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1468870792-7411-3-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Fam Zheng <famz@redhat.com>
CC: John Snow <jsnow@redhat.com>
Signed-off-by: NJohn Snow <jsnow@redhat.com>

Code to set and clear state associated with retry in moved into
ide_set_retry and ide_clear_retry to make adding retry setups easier.
Signed-off-by: NEvgeny Yakovlev <eyakovlev@virtuozzo.com>
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1468870792-7411-2-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Fam Zheng <famz@redhat.com>
CC: John Snow <jsnow@redhat.com>
Signed-off-by: NJohn Snow <jsnow@redhat.com>

Signed-off-by: NLluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Homogenizes the command capabilities with QMP.
Signed-off-by: NLluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Events with the 'vcpu' property are conditionally emitted according to
their per-vCPU state. Other events are emitted normally based on their
global tracing state.

Note that the per-vCPU condition check applies to all tracing backends.
Signed-off-by: NLluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Each vCPU gets a 'trace_dstate' bitmap to control the per-vCPU dynamic
tracing state of events with the 'vcpu' property.
Signed-off-by: NLluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Signed-off-by: NLluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Eliminates a future compilation error when UI code includes the tracing
headers (indirectly pulling "disas/bfd.h" through "qom/cpu.h") and
GLib's i18n '_' macro.
Signed-off-by: NLluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

A new event attribute 'cpu_id' is added to have a separate ID
space ('TRACE_VCPU_*') for all events with the 'vcpu' property.

These are later used to identify which events are enabled on each vCPU.
Signed-off-by: NLluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

[Changed const char *trace_file to char *trace_file since it's a
heap-allocated string that needs to be freed.  This type is also
returned by trace_opt_parse() and used in vl.c.

Also fixed coding style on for(;;) and else statement as suggested by
Eric Blake <eblake@redhat.com> since the patch modifies these lines or
close enough.
--Stefan]
Signed-off-by: NLluís Vilanova <vilanova@ac.upc.edu>
Message-id: 146860252322.30668.18276041739086338328.stgit@fimbulvetr.bsc.es
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

[Changed const char *trace_file to char *trace_file since it's a
heap-allocated string that needs to be freed.  This type is also
returned by trace_opt_parse() and used in vl.c.
--Stefan]
Signed-off-by: NLluís Vilanova <vilanova@ac.upc.edu>
Message-id: 146860251784.30668.17339867835129075077.stgit@fimbulvetr.bsc.es
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

# gpg: Signature made Mon 18 Jul 2016 17:58:27 BST
# gpg:                using RSA key 0x9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/block-pull-request:
  MAINTAINERS: Add include/block/aio.h to block I/O path section
  virtio-blk: dataplane cleanup
  checkpatch: consider git extended headers valid patches
  aio-posix: remove useless parameter
  linux-aio: prevent submitting more than MAX_EVENTS
  aio_ctx_check: follow CODING_STYLE
  linux-aio: share one LinuxAioState within an AioContext
  spec/parallels: fix a mistake
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

QEMU supports ARI on downstream ports and assigned devices may support
ARI in their extended capabilities.  The endpoint ARI capability
specifies the next function, such that the OS doesn't need to walk
each possible function, however this next function is relative to the
host, not the guest.  This leads to device discovery issues when we
combine separate functions into virtual multi-function packages in a
guest.  For example, SR-IOV VFs are not enumerated by simply probing
the function address space, therefore the ARI next-function field is
zero.  When we combine multiple VFs together as a multi-function
device in the guest, the guest OS identifies ARI is enabled, relies on
this next-function field, and stops looking for additional function
after the first is found.

Long term we should expose the ARI capability to the guest to enable
configurations with more than 8 functions per slot, but this requires
additional QEMU PCI infrastructure to manage the next-function field
for multiple, otherwise independent devices.  In the short term,
hiding this capability allows equivalent functionality to what we
currently have on non-express chipsets.
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Reviewed-by: NMarcel Apfelbaum <marcel@redhat.com>

We want the travis build bot to post notifications on IRC only for the
master qemu repository and not the various forks/branches of
others. Currently there is no direct option to restrict the updates to
one repository. This is being worked upon by the developers and
tracked in https://github.com/travis-ci/travis-ci/issues/1094.

Until such time, we can use the workaround as posted in
ref. https://github.com/facebook/flow/pull/1822.

This basically creates an ecrypted string which decrypts to qemu IRC
channel only on "qemu/qemu" repo and not on the forks. This enables
the build bot to notify the IRC only for the main repo.
Signed-off-by: NPranith Kumar <bobby.prani@gmail.com>
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>

This file is actually the header for async.c and aio-*.c., so add it to
the same section.
Suggested-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NFam Zheng <famz@redhat.com>
Message-id: 1468826387-10473-1-git-send-email-famz@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

No need duplicate the judgment, there is one in function entry.

Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Max Reitz <mreitz@redhat.com>
Signed-off-by: NCao jin <caoj.fnst@cn.fujitsu.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Message-id: 1468814749-14510-1-git-send-email-caoj.fnst@cn.fujitsu.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Renames look like this with git-diff(1) when diff.renames = true is set:

  diff --git a/a b/b
  similarity index 100%
  rename from a
  rename to b

This raises the "Does not appear to be a unified-diff format patch"
error because checkpatch.pl only considers a diff valid if it contains
at least one "@@" hunk.

This patch accepts renames and copies too so that checkpatch.pl exits
successfully when a diff only renames/copies files.  The git diff
extended header format is described on the git-diff(1) man page.
Reported-by: NColin Lord <clord@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-id: 1468576014-28788-1-git-send-email-stefanha@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Parameter **errp of aio_context_setup() is useless, remove it
and clean up the related code.

Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Fam Zheng <famz@redhat.com>
Cc: Eric Blake <eblake@redhat.com>
Signed-off-by: NCao jin <caoj.fnst@cn.fujitsu.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-id: 1468578524-23433-1-git-send-email-caoj.fnst@cn.fujitsu.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Invoking io_setup(MAX_EVENTS) we ask kernel to create ring buffer for us
with specified number of events.  But kernel ring buffer allocation logic
is a bit tricky (ring buffer is page size aligned + some percpu allocation
are required) so eventually more than requested events number is allocated.

From a userspace side we have to follow the convention and should not try
to io_submit() more or logic, which consumes completed events, should be
changed accordingly.  The pitfall is in the following sequence:

    MAX_EVENTS = 128
    io_setup(MAX_EVENTS)

    io_submit(MAX_EVENTS)
    io_submit(MAX_EVENTS)

    /* now 256 events are in-flight */

    io_getevents(MAX_EVENTS) = 128

    /* we can handle only 128 events at once, to be sure
     * that nothing is pended the io_getevents(MAX_EVENTS)
     * call must be invoked once more or hang will happen. */

To prevent the hang or reiteration of io_getevents() call this patch
restricts the number of in-flights, which is now limited to MAX_EVENTS.
Signed-off-by: NRoman Pen <roman.penyaev@profitbricks.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Message-id: 1468415004-31755-1-git-send-email-roman.penyaev@profitbricks.com
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: qemu-devel@nongnu.org
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

replace tab with spaces
Signed-off-by: NCao jin <caoj.fnst@cn.fujitsu.com>
Message-id: 1468501843-14927-1-git-send-email-caoj.fnst@cn.fujitsu.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

This has better performance because it executes fewer system calls
and does not use a bottom half per disk.

Originally proposed by Ming Lei.

[Changed #include "raw-aio.h" to "block/raw-aio.h" in win32-aio.c to fix
build error as reported by Peter Maydell <peter.maydell@linaro.org>.
--Stefan]
Acked-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1467650000-51385-1-git-send-email-pbonzini@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

squash! linux-aio: share one LinuxAioState within an AioContext

We have only one flag for now - Empty Image flag. The patch fixes unused
bits specification and marks bit 1 as usused.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: NDenis V. Lunev <den@openvz.org>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>