Commit Graph

51595 Commits

Author SHA1 Message Date
Peter Maydell e295a154c2 HMP pull
Note, I had seen a fail in the vhost-user/flags-mismatch on one
 host in one build, but not others with the same patches; and these patches
 go nowhere near that, so I think that's a separate vhost-user issue.
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Merge remote-tracking branch 'remotes/dgilbert/tags/pull-hmp-20170221' into staging

HMP pull

Note, I had seen a fail in the vhost-user/flags-mismatch on one
host in one build, but not others with the same patches; and these patches
go nowhere near that, so I think that's a separate vhost-user issue.

# gpg: Signature made Tue 21 Feb 2017 18:49:25 GMT
# gpg:                using RSA key 0x0516331EBC5BFDE7
# gpg: Good signature from "Dr. David Alan Gilbert (RH2) <dgilbert@redhat.com>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 45F5 C71B 4A0C B7FB 977A  9FA9 0516 331E BC5B FDE7

* remotes/dgilbert/tags/pull-hmp-20170221:
  monitor: Fix crashes when using HMP commands without CPU
  monitor: add poll-* properties into query-iothreads result
  hmp: fix block_set_io_throttle

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-21 19:41:57 +00:00
Thomas Huth 854e67fea6 monitor: Fix crashes when using HMP commands without CPU
When running certain HMP commands ("info registers", "info cpustats",
"info tlb", "nmi", "memsave" or dumping virtual memory) with the "none"
machine, QEMU crashes with a segmentation fault. This happens because the
"none" machine does not have any CPUs by default, but these HMP commands
did not check for a valid CPU pointer yet. Add such checks now, so we get
an error message about the missing CPU instead.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1484309555-1935-1-git-send-email-thuth@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-21 18:29:01 +00:00
Pavel Hrdina 5fc00480ab monitor: add poll-* properties into query-iothreads result
IOthreads were recently extended by new properties that can
enable/disable and configure aio polling.  This will also allow
other tools that uses QEMU to probe for existence of those new
properties via query-qmp-schema.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Message-Id: <3163c16d6ab4257f7be9ad44fe9cc0ce8c359e5a.1486718555.git.phrdina@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-21 18:29:01 +00:00
Eric Blake 3f35c3b166 hmp: fix block_set_io_throttle
Commit 7a9877a made the 'device' parameter to BlockIOThrottle
optional, favoring 'id' instead.  But it forgot to update the
HMP usage to set has_device, which makes all attempts to change
throttling via HMP fail with "Need exactly one of 'device' and 'id'"

CC: qemu-stable@nongnu.org
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20170120230359.4244-1-eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-21 18:29:00 +00:00
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Merge remote-tracking branch 'remotes/cody/tags/block-pull-request' into staging

# gpg: Signature made Tue 21 Feb 2017 15:40:05 GMT
# gpg:                using RSA key 0xBDBE7B27C0DE3057
# gpg: Good signature from "Jeffrey Cody <jcody@redhat.com>"
# gpg:                 aka "Jeffrey Cody <jeff@codyprime.org>"
# gpg:                 aka "Jeffrey Cody <codyprime@gmail.com>"
# Primary key fingerprint: 9957 4B4D 3474 90E7 9D98  D624 BDBE 7B27 C0DE 3057

* remotes/cody/tags/block-pull-request:
  qemu-options: Fix broken sheepdog URL
  mirror: do not increase offset during initial zero_or_discard phase
  QAPI: Fix blockdev-add example documentation
  iscsi: Add blockdev-add support
  iscsi: Add timeout option
  iscsi: Add header-digest option
  iscsi: Add initiator-name option
  iscsi: Handle -iscsi user/password in bdrv_parse_filename()
  iscsi: Split URL into individual options

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-21 15:48:22 +00:00
Thomas Huth 6135c5e126 qemu-options: Fix broken sheepdog URL
The sheepdog URL is broken twice: First it uses a duplicated
http:// prefix, second the website seems to have moved to
https://sheepdog.github.io/sheepdog/ instead.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-02-21 10:38:09 -05:00
Anton Nefedov 90ab48eb07 mirror: do not increase offset during initial zero_or_discard phase
If explicit zeroing out before mirroring is required for the target image,
it moves the block job offset counter to EOF, then offset and len counters
count the image size twice. There is no harm but stats are confusing,
specifically the progress of the operation is always reported as 99% by
management tools.

The patch skips offset increase for the first "technical" pass over the
image. This should not cause any further harm.

Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1486045515-8009-1-git-send-email-den@openvz.org
CC: Jeff Cody <jcody@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
CC: Eric Blake <eblake@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-02-21 10:38:00 -05:00
Jeff Cody b166099712 QAPI: Fix blockdev-add example documentation
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-02-21 10:37:46 -05:00
Kevin Wolf 31eb1202d3 iscsi: Add blockdev-add support
This adds blockdev-add support for iscsi devices.

Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-02-21 10:37:34 -05:00
Kevin Wolf 1d56010482 iscsi: Add timeout option
This was previously only available with -iscsi. Again, after this patch,
the -iscsi option only takes effect if an URL is given. New users are
supposed to use the new driver-specific option.

All -iscsi options have a corresponding driver-specific option for the
iscsi block driver now.

Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-02-21 10:37:26 -05:00
Kevin Wolf 81aa2a0fb5 iscsi: Add header-digest option
This was previously only available with -iscsi. Again, after this patch,
the -iscsi option only takes effect if an URL is given. New users are
supposed to use the new driver-specific option.

Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-02-21 10:37:16 -05:00
Kevin Wolf d4e799292c iscsi: Add initiator-name option
This was previously only available with -iscsi. Again, after this patch,
the -iscsi option only takes effect if an URL is given. New users are
supposed to use the new driver-specific option.

Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-02-21 10:37:08 -05:00
Kevin Wolf 4317142020 iscsi: Handle -iscsi user/password in bdrv_parse_filename()
This splits the logic in the old parse_chap() function into a part that
parses the -iscsi options into the new driver-specific options, and
another part that actually applies those options (called apply_chap()
now).

Note that this means that username and password specified with -iscsi
only take effect when a URL is provided. This is intentional, -iscsi is
a legacy interface only supported for compatibility, new users should
use the proper driver-specific options.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-02-21 10:36:57 -05:00
Kevin Wolf d5895fcb1d iscsi: Split URL into individual options
This introduces a .bdrv_parse_filename handler for iscsi which parses an
URL if given and translates it to individual options.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-02-21 10:36:34 -05:00
Peter Maydell a1cf5fac2b Changes to -drive without if= and with if=scsi
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Merge remote-tracking branch 'remotes/armbru/tags/pull-block-2017-02-21' into staging

Changes to -drive without if= and with if=scsi

# gpg: Signature made Tue 21 Feb 2017 12:22:35 GMT
# gpg:                using RSA key 0x3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-block-2017-02-21:
  hw/i386: Deprecate -drive if=scsi with PC machine types
  hw: Deprecate -drive if=scsi with non-onboard HBAs
  hw/scsi: Concentrate -drive if=scsi auto-create in one place
  hw: Drop superfluous special checks for orphaned -drive
  blockdev: Make orphaned -drive fatal
  blockdev: Improve message for orphaned -drive
  hw/arm/highbank: Default -drive to if=ide instead of if=scsi
  hw: Default -drive to if=none instead of scsi when scsi cannot work
  hw: Default -drive to if=none instead of ide when ide cannot work
  hw/arm/cubieboard hw/arm/xlnx-ep108: Fix units_per_default_bus
  hw: Default -drive to if=ide explicitly where it works

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-21 13:58:50 +00:00
Markus Armbruster f778a82f0c hw/i386: Deprecate -drive if=scsi with PC machine types
The PC machines (pc-q35-* pc-i440fx-* pc-* isapc xenfv) automatically
create lsi53c895a SCSI HBAs and SCSI devices to honor -drive if=scsi.
For giggles, try -drive if=scsi,bus=25,media=cdrom --- this makes QEMU
create 25 of them.

lsi53c895a is thoroughly obsolete (PCI Ultra2 SCSI, ca. 2000), and
currently has no maintainer in QEMU.  megasas is a better choice,
except with old OSes that lack drivers.  virtio-scsi is a much better
choice when you have a driver, but only (newish) Linux comes with one
in the box.  There is no good default that works for all guests.

Encourage users to pick a non-obsolete SCSI HBA that works for them by
deprecating -drive if=scsi.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1487161136-9018-4-git-send-email-armbru@redhat.com>
Acked-By: Paolo Bonzini <pbonzini@redhat.com>
2017-02-21 13:17:45 +01:00
Markus Armbruster a64aa5785d hw: Deprecate -drive if=scsi with non-onboard HBAs
Block backends defined with "-drive if=T" with T other than "none" are
meant to be picked up by machine initialization code: a suitable
frontend gets created and wired up automatically.

Drives defined with if=scsi are also picked up by SCSI HBAs added with
-device, unlike other interface types.  Deprecate this usage, as follows.

Create the frontends for onboard HBAs in machine initialization code,
exactly like we do for if=ide and other interface types.  Change
scsi_legacy_handle_cmdline() to create a frontend only when it's still
missing, and warn that this usage is deprecated.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1487161136-9018-3-git-send-email-armbru@redhat.com>
2017-02-21 13:17:45 +01:00
Markus Armbruster fb8b660e17 hw/scsi: Concentrate -drive if=scsi auto-create in one place
The logic to create frontends for -drive if=scsi is in SCSI HBAs.  For
all other interface types, it's in machine initialization code.

A few machine types create the SCSI HBAs necessary for that.  That's
also not done for other interface types.

I'm going to deprecate these SCSI eccentricities.  In preparation for
that, create the frontends in main() instead of the SCSI HBAs, by
calling new function scsi_legacy_handle_cmdline() there.

Note that not all SCSI HBAs create frontends.  Take care not to change
that.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1487161136-9018-2-git-send-email-armbru@redhat.com>
Acked-By: Paolo Bonzini <pbonzini@redhat.com>
2017-02-21 13:17:45 +01:00
Markus Armbruster 8f2d75e81d hw: Drop superfluous special checks for orphaned -drive
We've traditionally rejected orphans here and there, but not
systematically.  For instance, the sun4m machines have an onboard SCSI
HBA (bus=0), and have always rejected bus>0.  Other machines with an
onboard SCSI HBA don't.

Commit a66c9dc made all orphans trigger a warning, and the previous
commit turned this into an error.  The checks "here and there" are now
redundant.  Drop them.

Note that the one in mips_jazz.c was wrong: it rejected bus > MAX_FD,
but MAX_FD is the number of floppy drives per bus.

Error messages change from

    $ qemu-system-x86_64 -drive if=ide,bus=2
    qemu-system-x86_64: Too many IDE buses defined (3 > 2)
    $ qemu-system-mips64 -M magnum,accel=qtest -drive if=floppy,bus=2,id=fd1
    qemu: too many floppy drives
    $ qemu-system-sparc -M LX -drive if=scsi,bus=1
    qemu: too many SCSI bus

to

    $ qemu-system-x86_64 -drive if=ide,bus=2
    qemu-system-x86_64: -drive if=ide,bus=2: machine type does not support if=ide,bus=2,unit=0
    $ qemu-system-mips64 -M magnum,accel=qtest -drive if=floppy,bus=2,id=fd1
    qemu-system-mips64: -drive if=floppy,bus=2,id=fd1: machine type does not support if=floppy,bus=2,unit=0
    $ qemu-system-sparc -M LX -drive if=scsi,bus=1
    qemu-system-sparc: -drive if=scsi,bus=1: machine type does not support if=scsi,bus=1,unit=0

Cc: John Snow <jsnow@redhat.com>
Cc: "Hervé Poussineau" <hpoussin@reactos.org>
Cc: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1487153147-11530-9-git-send-email-armbru@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2017-02-21 13:17:45 +01:00
Markus Armbruster 720b8dc052 blockdev: Make orphaned -drive fatal
Block backends defined with "-drive if=T" with T other than "none" are
meant to be picked up by machine initialization code: a suitable
frontend gets created and wired up automatically.

If machine initialization code doesn't comply, the block backend
remains unused.  This triggers a warning since commit a66c9dc, v2.2.0.
Drives created by default are exempted; use -nodefaults to get rid of
them.

Turn this warning into an error.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1487153147-11530-8-git-send-email-armbru@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2017-02-21 13:17:45 +01:00
Markus Armbruster 664cc623bf blockdev: Improve message for orphaned -drive
We warn when a -drive isn't supported by the machine type (commit
a66c9dc):

    $ qemu-system-x86_64 -S -display none -drive if=mtd
    Warning: Orphaned drive without device: id=mtd0,file=,if=mtd,bus=0,unit=0

Improve this to point to the offending bit of configuration:

    qemu-system-x86_64: -drive if=mtd: warning: machine type does not support if=mtd,bus=0,unit=0

Especially nice when it's hidden behind -readconfig foo.cfg:

    qemu-system-x86_64:foo.cfg:140: warning: machine type does not support if=mtd,bus=0,unit=0

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1487153147-11530-7-git-send-email-armbru@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2017-02-21 13:17:40 +01:00
Markus Armbruster 2a7ae4ee50 hw/arm/highbank: Default -drive to if=ide instead of if=scsi
These machines have no onboard SCSI HBA, and no way to plug one.
-drive if=scsi therefore cannot work.  They do have an onboard IDE
controller (sysbus-ahci), but fail to honor if=ide.

Change their default to if=ide, and add a TODO comment on what needs
to be done to actually honor -drive if=ide.

Cc: Rob Herring <robh@kernel.org>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: qemu-arm@nongnu.org
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1487153147-11530-6-git-send-email-armbru@redhat.com>
2017-02-21 13:10:53 +01:00
Markus Armbruster 7e465513c1 hw: Default -drive to if=none instead of scsi when scsi cannot work
Block backends defined with -drive if=scsi are meant to be picked up
by machine initialization code: a suitable frontend gets created and
wired up automatically.

if=scsi drives not picked up that way can still be used with -device
as if they had if=none, but that's unclean and best avoided.  Unused
ones produce an "Orphaned drive without device" warning.

A few machine types default to if=scsi, even though they don't
actually have a SCSI HBA.  This makes no sense.  Change their default
to if=none.  Affected machines:

* aarch64/arm: realview-pbx-a9 vexpress-a9 vexpress-a15 xilinx-zynq-a9

Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: "Edgar E. Iglesias" <edgar.iglesias@gmail.com>
Cc: Alistair Francis <alistair.francis@xilinx.com>
Cc: qemu-arm@nongnu.org
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Message-Id: <1487153147-11530-5-git-send-email-armbru@redhat.com>
2017-02-21 13:10:53 +01:00
Markus Armbruster a27fa28f03 hw: Default -drive to if=none instead of ide when ide cannot work
Block backends defined with -drive if=ide are meant to be picked up by
machine initialization code: a suitable frontend gets created and
wired up automatically.

if=ide drives not picked up that way can still be used with -device as
if they had if=none, but that's unclean and best avoided.  Unused ones
produce an "Orphaned drive without device" warning.

-drive parameter "if" is optional, and the default depends on the
machine type.  If a machine type doesn't specify a default, the
default is "ide".

Many machine types implicitly default to if=ide that way, even though
they don't actually have an IDE controller.  This makes no sense.

Change the implicit default to if=none.  Affected machines:

* all targets: none
* aarch64/arm: akita ast2500 canon cheetah collie connex imx25
  integratorcp kzm lm3s6965evb lm3s811evb mainstone musicpal n800 n810
  netduino2 nuri palmetto realview romulus sabrelite smdkc210 sx1 sx1
  verdex z2
* cris: axis-dev88
* i386/x86_64: xenpv
* lm32: lm32-evr lm32-uclinux milkymist
* m68k: an5206 dummy mcf5208evb
* microblaze/microblazeel: petalogix-ml605 petalogix-s3adsp1800
* mips/mips64/mips64el/mipsel: mipssim
* moxie: moxiesim
* or32: or32-sim
* ppc/ppc64/ppcemb: bamboo ref405ep taihu virtex-ml507
* ppc/ppc64: mpc8544ds ppce500
* sh4/sh4eb: shix
* sparc: leon3_generic
* sparc64: niagara
* tricore: tricore_testboard
* unicore32: puv3
* xtensa/xtensaeb: kc705 lx200 lx60 ml605 sim

None of these machines have an IDE controller, let alone code to
honor if=ide.

Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: qemu-arm@nongnu.org
Cc: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: xen-devel@lists.xensource.com
Cc: Michael Walle <michael@walle.cc>
Cc: Laurent Vivier <laurent@vivier.eu>
Cc: Anthony Green <green@moxielogic.com>
Cc: Jia Liu <proljc@gmail.com>
Cc: Alexander Graf <agraf@suse.de>
Cc: qemu-ppc@nongnu.org
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Fabien Chouteau <chouteau@adacore.com>
Cc: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Cc: Artyom Tarasenko <atar4qemu@gmail.com>
Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-By: Artyom Tarasenko <atar4qemu@gmail.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1487153147-11530-4-git-send-email-armbru@redhat.com>
2017-02-21 13:10:53 +01:00
Markus Armbruster e0319b0302 hw/arm/cubieboard hw/arm/xlnx-ep108: Fix units_per_default_bus
Machine types cubieboard, xlnx-ep108, xlnx-zcu102 have an onboard AHCI
controller, but neglect to set their MachineClass member
units_per_default_bus = 1.  This permits -drive if=ide,unit=1, which
makes no sense for AHCI.  It also screws up index=N for odd N, because
it gets desugared to unit=1,bus=N/2

Doesn't really matter, because these machine types fail to honor
-drive if=ide.  Add the missing units_per_default_bus = 1 anyway,
along with a TODO comment on what needs to be done for -drive if=ide.

Also set block_default_type = IF_IDE explicitly.  It's currently the
default, but the next commit will change it to something more
sensible, and we want to keep the IF_IDE default for these three
machines.  See also the previous commit.

Cc: Beniamino Galvani <b.galvani@gmail.com>
Cc: Alistair Francis <alistair.francis@xilinx.com>
Cc: "Edgar E. Iglesias" <edgar.iglesias@gmail.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: qemu-arm@nongnu.org
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Alistair Francis <alistair.francis@xilinx.com>
Message-Id: <1487153147-11530-3-git-send-email-armbru@redhat.com>
2017-02-21 13:10:53 +01:00
Markus Armbruster 2059839baa hw: Default -drive to if=ide explicitly where it works
Block backends defined with -drive if=ide are meant to be picked up by
machine initialization code: a suitable frontend gets created and
wired up automatically.

if=ide drives not picked up that way can still be used with -device as
if they had if=none, but that's unclean and best avoided.  Unused ones
produce an "Orphaned drive without device" warning.

-drive parameter "if" is optional, and the default depends on the
machine type.  If a machine type doesn't specify a default, the
default is "ide".

Many machine types default to if=ide, even though they don't actually
have an IDE controller.  A future patch will change these defaults to
something more sensible.  To prepare for it, this patch makes default
"ide" explicit for the machines that actually pick up if=ide drives:

* alpha: clipper
* arm/aarch64: spitz borzoi terrier tosa
* i386/x86_64: generic-pc-machine (with concrete subtypes pc-q35-*
  pc-i440fx-* pc-* isapc xenfv)
* mips64el: fulong2e
* mips/mipsel/mips64el: malta mips
* ppc/ppc64: mac99 g3beige prep
* sh4/sh4eb: r2d
* sparc64: sun4u sun4v

Note that ppc64 machine powernv already sets an "ide" default
explicitly.  Its IDE controller isn't implemented, yet.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1487153147-11530-2-git-send-email-armbru@redhat.com>
2017-02-21 13:10:53 +01:00
Peter Maydell a0775e28cd Pull request
v2:
  * Rebased to resolve scsi conflicts
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Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

Pull request

v2:
 * Rebased to resolve scsi conflicts

# gpg: Signature made Tue 21 Feb 2017 11:56:24 GMT
# 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: (24 commits)
  coroutine-lock: make CoRwlock thread-safe and fair
  coroutine-lock: add mutex argument to CoQueue APIs
  coroutine-lock: place CoMutex before CoQueue in header
  test-aio-multithread: add performance comparison with thread-based mutexes
  coroutine-lock: add limited spinning to CoMutex
  coroutine-lock: make CoMutex thread-safe
  block: document fields protected by AioContext lock
  async: remove unnecessary inc/dec pairs
  aio-posix: partially inline aio_dispatch into aio_poll
  block: explicitly acquire aiocontext in aio callbacks that need it
  block: explicitly acquire aiocontext in bottom halves that need it
  block: explicitly acquire aiocontext in callbacks that need it
  block: explicitly acquire aiocontext in timers that need it
  aio: push aio_context_acquire/release down to dispatching
  qed: introduce qed_aio_start_io and qed_aio_next_io_cb
  blkdebug: reschedule coroutine on the AioContext it is running on
  coroutine-lock: reschedule coroutine on the AioContext it was running on
  nbd: convert to use qio_channel_yield
  io: make qio_channel_yield aware of AioContexts
  io: add methods to set I/O handlers on AioContext
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-21 11:58:03 +00:00
Paolo Bonzini a7b91d35ba coroutine-lock: make CoRwlock thread-safe and fair
This adds a CoMutex around the existing CoQueue.  Because the write-side
can just take CoMutex, the old "writer" field is not necessary anymore.
Instead of removing it altogether, count the number of pending writers
during a read-side critical section and forbid further readers from
entering.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213181244.16297-7-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:40 +00:00
Paolo Bonzini 1ace7ceac5 coroutine-lock: add mutex argument to CoQueue APIs
All that CoQueue needs in order to become thread-safe is help
from an external mutex.  Add this to the API.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213181244.16297-6-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:40 +00:00
Paolo Bonzini f8c6e1cbc3 coroutine-lock: place CoMutex before CoQueue in header
This will avoid forward references in the next patch.  It is also
more logical because CoQueue is not anymore the basic primitive.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213181244.16297-5-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:40 +00:00
Paolo Bonzini c05df34a87 test-aio-multithread: add performance comparison with thread-based mutexes
Add two implementations of the same benchmark as the previous patch,
but using pthreads.  One uses a normal QemuMutex, the other is Linux
only and implements a fair mutex based on MCS locks and futexes.
This shows that the slower performance of the 5-thread case is due to
the fairness of CoMutex, rather than to coroutines.  If fairness does
not matter, as is the case with two threads, CoMutex can actually be
faster than pthreads.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213181244.16297-4-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:40 +00:00
Paolo Bonzini 480cff6322 coroutine-lock: add limited spinning to CoMutex
Running a very small critical section on pthread_mutex_t and CoMutex
shows that pthread_mutex_t is much faster because it doesn't actually
go to sleep.  What happens is that the critical section is shorter
than the latency of entering the kernel and thus FUTEX_WAIT always
fails.  With CoMutex there is no such latency but you still want to
avoid wait and wakeup.  So introduce it artificially.

This only works with one waiters; because CoMutex is fair, it will
always have more waits and wakeups than a pthread_mutex_t.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213181244.16297-3-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:40 +00:00
Paolo Bonzini fed20a70e3 coroutine-lock: make CoMutex thread-safe
This uses the lock-free mutex described in the paper '"Blocking without
Locking", or LFTHREADS: A lock-free thread library' by Gidenstam and
Papatriantafilou.  The same technique is used in OSv, and in fact
the code is essentially a conversion to C of OSv's code.

[Added missing coroutine_fn in tests/test-aio-multithread.c.
--Stefan]

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213181244.16297-2-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:40 +00:00
Paolo Bonzini 91bcea4899 block: document fields protected by AioContext lock
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-19-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:40 +00:00
Paolo Bonzini bd451435c0 async: remove unnecessary inc/dec pairs
Pull the increment/decrement pair out of aio_bh_poll and into the
callers.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-18-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:40 +00:00
Paolo Bonzini a153bf52b3 aio-posix: partially inline aio_dispatch into aio_poll
This patch prepares for the removal of unnecessary lockcnt inc/dec pairs.
Extract the dispatching loop for file descriptor handlers into a new
function aio_dispatch_handlers, and then inline aio_dispatch into
aio_poll.

aio_dispatch can now become void.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-17-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:39 +00:00
Paolo Bonzini b9e413dd37 block: explicitly acquire aiocontext in aio callbacks that need it
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-16-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:39 +00:00
Paolo Bonzini 1919631e6b block: explicitly acquire aiocontext in bottom halves that need it
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-15-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:39 +00:00
Paolo Bonzini 9d45665448 block: explicitly acquire aiocontext in callbacks that need it
This covers both file descriptor callbacks and polling callbacks,
since they execute related code.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-14-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:36 +00:00
Paolo Bonzini 2f47da5f7f block: explicitly acquire aiocontext in timers that need it
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-13-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:14:08 +00:00
Paolo Bonzini 0836c72f70 aio: push aio_context_acquire/release down to dispatching
The AioContext data structures are now protected by list_lock and/or
they are walked with FOREACH_RCU primitives.  There is no need anymore
to acquire the AioContext for the entire duration of aio_dispatch.
Instead, just acquire it before and after invoking the callbacks.
The next step is then to push it further down.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-12-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:14:08 +00:00
Paolo Bonzini b20123a28b qed: introduce qed_aio_start_io and qed_aio_next_io_cb
qed_aio_start_io and qed_aio_next_io will not have to acquire/release
the AioContext, while qed_aio_next_io_cb will.  Split the functionality
and gain a little type-safety in the process.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-11-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:14:08 +00:00
Paolo Bonzini e5c67ab552 blkdebug: reschedule coroutine on the AioContext it is running on
Keep the coroutine on the same AioContext.  Without this change,
there would be a race between yielding the coroutine and reentering it.
While the race cannot happen now, because the code only runs from a single
AioContext, this will change with multiqueue support in the block layer.

While doing the change, replace custom bottom half with aio_co_schedule.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-10-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:14:08 +00:00
Paolo Bonzini a9d9235567 coroutine-lock: reschedule coroutine on the AioContext it was running on
As a small step towards the introduction of multiqueue, we want
coroutines to remain on the same AioContext that started them,
unless they are moved explicitly with e.g. aio_co_schedule.  This patch
avoids that coroutines switch AioContext when they use a CoMutex.
For now it does not make much of a difference, because the CoMutex
is not thread-safe and the AioContext itself is used to protect the
CoMutex from concurrent access.  However, this is going to change.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-9-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:14:08 +00:00
Paolo Bonzini ff82911cd3 nbd: convert to use qio_channel_yield
In the client, read the reply headers from a coroutine, switching the
read side between the "read header" coroutine and the I/O coroutine that
reads the body of the reply.

In the server, if the server can read more requests it will create a new
"read request" coroutine as soon as a request has been read.  Otherwise,
the new coroutine is created in nbd_request_put.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-8-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:14:08 +00:00
Paolo Bonzini c4c497d27f io: make qio_channel_yield aware of AioContexts
Support separate coroutines for reading and writing, and place the
read/write handlers on the AioContext that the QIOChannel is registered
with.

Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213135235.12274-7-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:14:07 +00:00
Paolo Bonzini bf88c1247f io: add methods to set I/O handlers on AioContext
This is in preparation for making qio_channel_yield work on
AioContexts other than the main one.

Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213135235.12274-6-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:14:07 +00:00
Paolo Bonzini 934ebf48c0 test-thread-pool: use generic AioContext infrastructure
Once the thread pool starts using aio_co_wake, it will also need
qemu_get_current_aio_context().  Make test-thread-pool create
an AioContext with qemu_init_main_loop, so that stubs/iothread.c
and tests/iothread.c can provide the rest.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213135235.12274-5-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:14:07 +00:00
Paolo Bonzini 35f106e684 block-backend: allow blk_prw from coroutine context
qcow2_create2 calls this.  Do not run a nested event loop, as that
breaks when aio_co_wake tries to queue the coroutine on the co_queue_wakeup
list of the currently running one.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213135235.12274-4-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:14:07 +00:00
Paolo Bonzini 0c330a734b aio: introduce aio_co_schedule and aio_co_wake
aio_co_wake provides the infrastructure to start a coroutine on a "home"
AioContext.  It will be used by CoMutex and CoQueue, so that coroutines
don't jump from one context to another when they go to sleep on a
mutex or waitqueue.  However, it can also be used as a more efficient
alternative to one-shot bottom halves, and saves the effort of tracking
which AioContext a coroutine is running on.

aio_co_schedule is the part of aio_co_wake that starts a coroutine
on a remove AioContext, but it is also useful to implement e.g.
bdrv_set_aio_context callbacks.

The implementation of aio_co_schedule is based on a lock-free
multiple-producer, single-consumer queue.  The multiple producers use
cmpxchg to add to a LIFO stack.  The consumer (a per-AioContext bottom
half) grabs all items added so far, inverts the list to make it FIFO,
and goes through it one item at a time until it's empty.  The data
structure was inspired by OSv, which uses it in the very code we'll
"port" to QEMU for the thread-safe CoMutex.

Most of the new code is really tests.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20170213135235.12274-3-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:14:07 +00:00