We are moving block-migration.c to the separated migration directory,
keep this file watched by block maintainers is a good idea.
Signed-off-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Remove first email address and let the one from which I am contributing.
Signed-off-by: NChrysostomos Nanakos <chris@include.gr>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

According to the specification, the low 16 bits should contain the number of
I/O submission queues, and the high 16 bits should contain the number of
I/O completion queues.
Signed-off-by: NAlex Friedman <alex@e8storage.com>
Acked-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

SCSI devices have multiple kinds of queries they need to respond
to, as defined in the "cmd inquiry" section in MMC-6 and SPC-3.

Relevent sections:
MMC-6 revision 2g:
      Non-VPD response data and pointer to SPC-3;
      Section 6.8 "Inquiry Command"
SPC-3 revision 23:
      Inquiry command and error handling:
      Section 6.4 "INQUIRY command"
      VPD data pages format:
      Section 7.6 "Vital product data parameters"

We implement these Vital Product Data queries for SCSI, but not for
ATAPI through IDE. The result is that if you are looking for the WWN
identifier via tools such as sg3_utils, you will be unable to query
our CD/DVD rom device to obtain it.

This patch adds the minimum number of mandatory responses as defined
by SPC-3, which include the "supported pages" response (page 0x00)
and the "Device Identification" response (page 0x83). It also correctly
responds when it receives a request for an illegal page to improve
error output from related tools.

The Device ID page contains an arbitrary list of identification
strings of various formats; the ID strings included in this patch
were chosen to mimic those provided by the libata driver when
emulating this SCSI query (model, serial, and wwn when present.)

Example:

# libata emulated response
[root@localhost ~]# sg_inq --id /dev/sda
VPD INQUIRY: Device Identification page
  Designation descriptor number 1, descriptor length: 24
    designator_type: vendor specific [0x0],  code_set: ASCII
    associated with the addressed logical unit
      vendor specific: QM00001
  Designation descriptor number 2, descriptor length: 72
    designator_type: T10 vendor identification,  code_set: ASCII
    associated with the addressed logical unit
      vendor id: ATA
      vendor specific: QEMU HARDDISK                           QM00001

# QEMU generated ATAPI response, with WWN
[root@localhost ~]# sg_inq --id /dev/sr0
VPD INQUIRY: Device Identification page
  Designation descriptor number 1, descriptor length: 24
    designator_type: vendor specific [0x0],  code_set: ASCII
    associated with the addressed logical unit
      vendor specific: QM00005
  Designation descriptor number 2, descriptor length: 72
    designator_type: T10 vendor identification,  code_set: ASCII
    associated with the addressed logical unit
      vendor id: ATA
      vendor specific: QEMU DVD-ROM                            QM00005
  Designation descriptor number 3, descriptor length: 12
    designator_type: NAA,  code_set: Binary
    associated with the addressed logical unit
      NAA 5, IEEE Company_id: 0xc50
      Vendor Specific Identifier: 0x15ea71bb
      [0x5000c50015ea71bb]

See also: hw/scsi/scsi-disk.c, scsi_disk_emulate_inquiry()
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Like BLOCK_OP_TYPE_BACKUP_SOURCE and BLOCK_OP_TYPE_BACKUP_TARGET,
block-commit involves two asymmetric devices.

This change is not user-visible (yet), because commit only works with
device names.

But once we enable backing reference in blockdev-add, or specifying
node-name in block-commit command, we don't want the user to start two
commit jobs on the same backing chain, which will corrupt things because
of the final bdrv_swap.

Before we have per category blockers, splitting this type is still
better.

[Resolved virtio-blk dataplane conflict by replacing
BLOCK_OP_TYPE_COMMIT with both BLOCK_OP_TYPE_COMMIT_{SOURCE, TARGET}.
They are safe since the block job runs in the same AioContext as the
dataplane IOThread.
--Stefan]
Signed-off-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

If bs->bl.max_write_zeroes is large and we end up in the unsupported
path we might allocate a lot of memory for the iovector and/or even
generate an oversized requests.

Fix this by limiting the request by the minimum of the reported
maximum transfer size or 16MB (32768 sectors).
Reported-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NPeter Lieven <pl@kamp.de>
Reviewed-by: NDenis V. Lunev <den@openvz.org>
Message-id: 1420457389-16332-1-git-send-email-pl@kamp.de
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Placing coroutines on the global pool should be preferrable, because it
can help all threads.  But if the global pool is full, we can still
try to save some allocations by stashing completed coroutines on the
local pool.  This is quite cheap too, because it does not require
atomic operations, and provides a gain of 15% in the best case.
Signed-off-by: NPeter Lieven <pl@kamp.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Message-id: 1417518350-6167-8-git-send-email-pbonzini@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

This is not needed anymore.  The new TLS-based algorithm is adaptive.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Message-id: 1417518350-6167-7-git-send-email-pbonzini@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

This patch removes the mutex by using fancy lock-free manipulation of
the pool.  Lock-free stacks and queues are not hard, but they can suffer
from the ABA problem so they are better avoided unless you have some
deferred reclamation scheme like RCU.  Otherwise you have to stick
with adding to a list, and emptying it completely.  This is what this
patch does, by coupling a lock-free global list of available coroutines
with per-CPU lists that are actually used on coroutine creation.

Whenever the destruction pool is big enough, the next thread that runs
out of coroutines will steal the whole destruction pool.  This is positive
in two ways:

1) the allocation does not have to do any atomic operation in the fast
path, it's entirely using thread-local storage.  Once every POOL_BATCH_SIZE
allocations it will do a single atomic_xchg.  Release does an atomic_cmpxchg
loop, that hopefully doesn't cause any starvation, and an atomic_inc.

A later patch will also remove atomic operations from the release path,
and try to avoid the atomic_xchg altogether---succeeding in doing so if
all devices either use ioeventfd or are not submitting requests actively.

2) in theory this should be completely adaptive.  The number of coroutines
around should be a little more than POOL_BATCH_SIZE * number of allocating
threads; so this also empties qemu_coroutine_adjust_pool_size.  (The previous
pool size was POOL_BATCH_SIZE * number of block backends, so it was a bit
more generous.  But if you actually have many high-iodepth disks, it's better
to put them in different iothreads, which will also use separate thread
pools and aio=native file descriptors).

This speeds up perf/cost (in tests/test-coroutine) by a factor of ~1.33.
No matter if we end with some kind of coroutine bypass scheme or not,
it cannot hurt to optimize hot code.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Message-id: 1417518350-6167-6-git-send-email-pbonzini@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

These operations are trivial to implement and do not have ABA problems.
They are enough to implement simple multiple-producer, single consumer
lock-free lists or, as in the next patch, the multiple consumers can
steal a whole batch of elements and process them at their leisure.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Message-id: 1417518350-6167-5-git-send-email-pbonzini@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

unsigned long is not large enough to represent 1000000000 * duration there.
Just use floating point.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Message-id: 1417518350-6167-4-git-send-email-pbonzini@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Destructors are the main additional feature of pthread TLS compared
to __thread.  If we were using C++ (hint, hint!) we could have used
thread-local objects with a destructor.  Since we are not, instead,
we add a simple Notifier-based API.

Note that the notifier must be per-thread as well.  We can add a
global list as well later, perhaps.

The Win32 implementation has some complications because a) detached
threads used not to have a QemuThreadData; b) the main thread does
not go through win32_start_routine, so we have to use atexit too.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Message-id: 1417518350-6167-3-git-send-email-pbonzini@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

ELF thread local storage is about 10% faster on tests/test-coroutine's
perf/cost test.  The timing on my machine is 190ns per iteration with
pthread TLS, 170 with ELF TLS.

Based on a patch by Kevin Wolf and Peter Lieven, but redone to follow
the model of coroutine-win32.c (including the important "noinline"
attribute!).

Platforms without thread-local storage (OpenBSD probably?) will need
a new-enough GCC for this to compile, in order to use the same emutls
support that Windows already relies on.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Message-id: 1417518350-6167-2-git-send-email-pbonzini@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

If I understand correctly, qemu-iotests never meant to be portable. We
only support Linux for all the shell cases, but didn't specify it for
python tests. Now add this and default all the python tests as Linux
only. If we cares enough later, we can override the parameter in
individual cases.
Signed-off-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Other cases have this, and this test is not portable as well, as we want
to add "make check-block" to "make check", it shouldn't fail on Mac OS
X.
Reported-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

The former is not portable because on Mac OSX it is /usr/bin/true.
Signed-off-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Signed-off-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

The allocator in malloc-pc has been extracted, so it can be used in every arch.
This operation showed that both the alloc and free functions can be also
generic.
Because of this, the QGuestAllocator has been removed from is function to wrap
the alloc and free function, and now just contains the allocator parameters.
As a result, only the allocator initalizer and unitializer are arch dependent.
Signed-off-by: NMarc Marí <marc.mari.barcelo@gmail.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Because of wrong return value of .save_live_pending() in
migration/block.c, migration finishes before the whole disk is
transferred. Such situation occurs when the migration process is fast
enough, for example when source and dest are on the same host.

If in the bulk phase we return something < max_size, we will skip
transferring the tail of the device. Currently we have "set pending to
BLOCK_SIZE if it is zero" for bulk phase, but there no guarantee, that
it will be < max_size.

True approach is to return, for example, max_size+1 when we are in the
bulk phase.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@parallels.com>
Message-id: 1419933856-4018-2-git-send-email-vsementsov@parallels.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Filter out the "main loop: WARNING: I/O thread spun for..." warning from
qemu output (it hardly matters for code specifically testing I/O).

Furthermore, use _filter_qemu in all the custom functions which run
qemu.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

This applies cases on drive-backup on blockdev-backup, except cases with
target format and mode.

Also add a case to check source == target.
Signed-off-by: NFam Zheng <famz@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Message-id: 1418899027-8445-5-git-send-email-famz@redhat.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Signed-off-by: NFam Zheng <famz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Message-id: 1418899027-8445-4-git-send-email-famz@redhat.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Similar to drive-backup, but this command uses a device id as target
instead of creating/opening an image file.

Also add blocker on target bs, since the target is also a named device
now.

Add check and report error for bs == target which became possible but is
an illegal case with introduction of blockdev-backup.
Signed-off-by: NFam Zheng <famz@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Message-id: 1418899027-8445-3-git-send-email-famz@redhat.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Signed-off-by: NFam Zheng <famz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Message-id: 1418899027-8445-2-git-send-email-famz@redhat.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Mirror and migration use dirty bitmaps for their purposes, and since
commit [block: per caller dirty bitmap] they use their own bitmaps, not
the global one. But they use old functions bdrv_set_dirty and
bdrv_reset_dirty, which change all dirty bitmaps.

Named dirty bitmaps series by Fam and Snow are affected: mirroring and
migration will spoil all (not related to this mirroring or migration)
named dirty bitmaps.

This patch fixes this by adding bdrv_set_dirty_bitmap and
bdrv_reset_dirty_bitmap, which change concrete bitmap. Also, to prevent
such mistakes in future, old functions bdrv_(set,reset)_dirty are made
static, for internal block usage.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@parallels.com>
CC: John Snow <jsnow@redhat.com>
CC: Fam Zheng <famz@redhat.com>
CC: Denis V. Lunev <den@openvz.org>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Message-id: 1417081246-3593-1-git-send-email-vsementsov@parallels.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Signed-off-by: NFam Zheng <famz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-id: 1418694024-26498-1-git-send-email-famz@redhat.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Sometimes, qemu does not have a filename to work with, so it does not
know which directory to use for a backing file specified by a relative
filename. Add a test which tests that qemu exits with an appropriate
error message.

Additionally, add a test for qemu-img create with a backing filename
relative to the backed image's base directory while omitting the image
size.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

When a vmdk image is created with a backing file, it is opened to check
whether it is indeed a vmdk file by letting qemu probe it. When doing
so, the backing filename is relative to the image's base directory so it
should be interpreted accordingly.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Relative backing filenames are always relative to the backed image's
directory; the same applies to image creation. Therefore, if the backing
file has to be opened for determining its size (in case the size has not
been explicitly specified) its filename should be interpreted relative
to the new image's base directory and not relative to qemu's working
directory.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

When using a relative backing file name, qemu needs to know the
directory of the top image file. For JSON filenames, such a directory
cannot be easily determined (e.g. how do you determine the directory of
a qcow2 BDS directly on top of a quorum BDS?). Therefore, do not allow
relative filenames for the backing file of BDSs only having a JSON
filename.

Furthermore, BDS::exact_filename should be used whenever possible. If
BDS::filename is not equal to BDS::exact_filename, the former will
always be a JSON object.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Introduce bdrv_get_full_backing_filename_from_filename(), a function
which takes the name of the backed file and a potentially relative
backing filename to produce the full (absolute) backing filename.

Use this function from bdrv_get_full_backing_filename().
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

CODING_STYLE states the following about braces around blocks:

> The opening brace is on the line that contains the control flow
> statement that introduces the new block; [...]

This is obviously impossible with multi-line conditions. Therefore,
CODING_STYLE does not make any clear statement about where to put the
opening brace after a multi-line condition.

There is a reason to prefer to place the opening brace on an own line
after such a condition while still placing it on the same line as the
"control flow statement" if possible; that reason is that the last line
of a multi-line condition is indented, in the case of "if", it is often
indented by four spaces, just as much as the first statement in the
block will be indented. This is hard to read as there is no clearly
visible distinction between condition and block. Placing the opening
brace on a separate line solves this issue.

Also, there are cases where placing the opening brace on a separate line
is the only viable option; if the previous line had nearly 80 characters
and splitting it is not desirable, the opening brace is naturally placed
on an own line.

This patch fixes checkpatch.pl to not complain about braces on own lines
if the condition introducing the block spanned more than one line, or if
the previous line had 79 or 80 characters.

Furthermore, the warning about not having braces around a block is fixed
to mind braces not being on the last line of the condition.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

This saves about 15% of the clock cycles spent on allocation.  Using the
slice allocator does not add a visible improvement; allocation is faster
than malloc, while freeing seems to be slower.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Most reads do not go past the end of the file, and they can use the
input QEMUIOVector instead of creating one.  This removes the
qemu_iovec_* functions from the profile.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

AioContext can be accessed recursively, in fact that's what we do with
aio_poll.  Marking the GSource as recursive avoids that GLib blocks it
and unblocks it around every call to aio_dispatch, which is a pretty
expensive operation.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Using /tmp, which is usually mounted as tmpfs, the quick group can be
quicker.

On my laptop (Lenovo T430s with Fedora 20), this reduces the time from
50s to 30s.
Signed-off-by: NFam Zheng <famz@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

For the purpose of allowing running quick group on tmpfs.
Signed-off-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

# gpg: Signature made Mon 12 Jan 2015 10:27:41 GMT using RSA key ID 81AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"

* remotes/stefanha/tags/net-pull-request:
  hw/net/xen_nic.c: Set 'netdev->mac' to NULL after free it
  hw/net/xen_nic.c: Need free 'netdev->nic' in net_free() instead of net_disconnect()
  hw/net/xen_nic.c: Free 'netdev->txs' when map 'netdev->rxs' fails
  net: remove all cleanup methods from NIC NetClientInfos
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Since net_init() checks whether 'netdev->mac' is NULL, before alloc it;
net_release() also need set 'netdev->mac' to NULL after free it.
Signed-off-by: NChen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

net_init() and net_free() are pairs, net_connect() and net_disconnect()
are pairs. net_init() creates 'netdev->nic', so also need free it in
net_free().
Signed-off-by: NChen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>