This is the "common part" to handle one cmd request. Refactor out for
later usage of dataplane iothread code.

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

The command direction according to the guest-passed buffers
is already stored in the VirtIOSCSIReq.  We can use it instead
of computing it again from req->elem.

Cc: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

This helps for cross-endian configurations.

Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The VirtQueueElement is a very big structure (>48k!), since it will be
initialzed by virtqueue_pop, we can save the expensive zeroing here.

This saves a few microseconds per request in my test:

[fio-test]      rw         bs         iodepth    jobs       bw         iops       latency
--------------------------------------------------------------------------------------------
Before          read       4k         1          1          110        28269      34
After           read       4k         1          1          131        33745      28

Whereas,

virtio-blk      read       4k         1          1          217        55673      16

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

Zeroing sense buffer for each scsi request is not efficient, we can just
leave it uninitialized because sense_len is set to 0.

Move the implicitly zeroed fields to the end of the structure and use a
partial memset.

The explicitly initialized fields (by scsi_req_alloc or scsi_req_new)
are moved to the beginning of the structure, before sense buffer, to
skip the memset.

Also change g_malloc0 to g_slice_alloc.

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

# gpg: Signature made Mon 22 Sep 2014 12:41:59 BST using RSA key ID 81AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"

* remotes/stefanha/tags/block-pull-request: (59 commits)
  block: Always compile virtio-blk dataplane
  vring: Better error handling if num is too large
  virtio: Import virtio_vring.h
  async: aio_context_new(): Handle event_notifier_init failure
  block: vhdx - fix reading beyond pointer during image creation
  block: delete cow block driver
  block/archipelago: Fix typo in qemu_archipelago_truncate()
  ahci: Add test_identify case to ahci-test.
  ahci: Add test_hba_enable to ahci-test.
  ahci: Add test_hba_spec to ahci-test.
  ahci: properly shadow the TFD register
  ahci: add test_pci_enable to ahci-test.
  ahci: Add test_pci_spec to ahci-test.
  ahci: MSI capability should be at 0x80, not 0x50.
  ahci: Adding basic functionality qtest.
  layout: Add generators for refcount table and blocks
  fuzz: Add fuzzing functions for entries of refcount table and blocks
  docs: List all image elements currently supported by the fuzzer
  qapi/block-core: Add "new" qcow2 options
  qcow2: Add overlap-check.template option
  ...

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

trivial patches for 2014-09-22

# gpg: Signature made Mon 22 Sep 2014 09:10:03 BST using RSA key ID A4C3D7DB
# gpg: Good signature from "Michael Tokarev <mjt@tls.msk.ru>"
# gpg:                 aka "Michael Tokarev <mjt@corpit.ru>"
# gpg:                 aka "Michael Tokarev <mjt@debian.org>"
# 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: 6EE1 95D1 886E 8FFB 810D  4324 457C E0A0 8044 65C5
#      Subkey fingerprint: 6F67 E18E 7C91 C5B1 5514  66A7 BEE5 9D74 A4C3 D7DB

* remotes/mjt/tags/trivial-patches-2014-09-22:
  arch_init: Setting QEMU_ARCH enum straight
  pc: Add missing 'static' attribute
  block: allow creation of fixed vhdx images
  vl: Print maxmem in hex format for error message
  configure: trivial fixes
  xen-hvm.c: Always return -1 when failure occurs in xen_hvm_init()
  rdma: Fix incorrect description in comments
  Fix typos and misspellings in comments
  qemu-char: Permit only a single "stdio" character device

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

Dataplane doesn't depend on linux-aio any more, so we don't need the
compiling condition now.

Configure options are kept but just print a message.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1410329871-28885-4-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

To be more consistent inside this function.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1410329871-28885-3-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

This header has no further dependencies. It only has some stable data
types and primitive functions, so we can copy it to include/hw/virtio in
order to allow vring code (and its user virtio-blk dataplane) to be
built unconditionally, even for cross compiling.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1410329871-28885-2-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

On a system with a low limit of open files the initialization
of the event notifier could fail and QEMU exits without printing any
error information to the user.

The problem can be easily reproduced by enforcing a low limit of open
files and start QEMU with enough I/O threads to hit this limit.

The same problem raises, without the creation of I/O threads, while
QEMU initializes the main event loop by enforcing an even lower limit of
open files.

This commit adds an error message on failure:

 # qemu [...] -object iothread,id=iothread0 -object iothread,id=iothread1
 qemu: Failed to initialize event notifier: Too many open files in system

Signed-off-by: Chrysostomos Nanakos <cnanakos@grnet.gr>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

In vhdx_create_metadata(), we allocate 40 bytes to entry_buffer for
the various metadata table entries.  However, we write out 64kB from
that buffer into the new file.  Only write out the correct 40 bytes.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

This patch removes support for the cow file format.

Normally we do not break backwards compatibility but in this case there
is no impact and it is the most logical option.  Extraordinary claims
require extraordinary evidence so I will show why removing the cow block
driver is the right thing to do.

The cow file format is the disk image format for Usermode Linux, a way
of running a Linux system in userspace.  The performance of UML was
never great and it was hacky, but it enjoyed some popularity before
hardware virtualization support became mainstream.

QEMU's block/cow.c is supposed to read this image file format.
Unfortunately the file format was underspecified:

1. Earlier Linux versions used the MAXPATHLEN constant for the backing
   filename field.  The value of MAXPATHLEN can change, so Linux
   switched to a 4096 literal but QEMU has a 1024 literal.

2. Padding was not used on the header struct (both in the Linux kernel
   and in QEMU) so the struct layout varied across architectures.  In
   particular, i386 and x86_64 were different due to int64_t alignment
   differences.  Linux now uses __attribute__((packed)), QEMU does not.

Therefore:

1. QEMU cow images do not conform to the Linux cow image file format.

2. cow images cannot be shared between different host architectures.

This means QEMU cow images are useless and QEMU has not had bug reports
from users actually hitting these issues.

Let's get rid of this thing, it serves no purpose and no one will be
affected.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1410877464-20481-1-git-send-email-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Fix a typo introduced by 94c80a43

Signed-off-by: Chrysostomos Nanakos <cnanakos@grnet.gr>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Utilizing all of the bring-up code in pci_enable and hba_enable,
this test issues a simple IDENTIFY command via the HBA and retrieves
the response via the PIO receive mechanisms of the HBA.

Bugs: The DPS interrupt (Descriptor Processed Status) does not
currently get set. This will need to be adjusted in a future
patch series when the AHCI DMA pathways are reworked to allow
the feature, which may be utilized by OSX guests.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1408643079-30675-9-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

This test engages the HBA functionality and initializes
values to sane defaults to allow for minimal HBA functionality.

Buffers are allocated and pointers are updated to allow minimal
I/O commands to complete as expected. Error registers and responses
are sanity checked for specification adherence.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1408643079-30675-8-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Add a test routine that checks the boot-up values of the HBA
configuration memory space against the AHCI 1.3 specification
and Intel ICH9 data sheet (for Q35 machines) for adherence and
sane values.

The HBA is not yet engaged or put into the idle state.

[Replaced g_assert_false(...) with g_assert(!...) for glib <2.38
compatibility, reported by Peter Maydell <peter.maydell@linaro.org>.
--Stefan]

Signed-off-by: John Snow <jsnow@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1408643079-30675-7-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

In a real AHCI device, several S/ATA registers are mirrored or shadowed
within the AHCI register set. These registers are not updated
synchronously for each read access, but are instead updated after a
Device-to-Host Register FIS packet is received. The D2H FIS contains
the values from these registers on the device.

In QEMU, by reaching directly into the device to grab these bits before
they are "sent," we may introduce race conditions where unexpected
values are present "before they are sent" which could cause issues for
some guests, particularly if an attempt is made to read the PxTFD
register prior to enabling the port, where incorrect values will be read.

This patch also addresses the boot-time values for the PxTFD and PxSIG
registers to bring them in line with the AHCI 1.3 specification.

Lastly, several fields (PxTFD, PxSIG and PxSACT) are read-only,
and any attempts to write to them should be ignored.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1408643079-30675-6-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

This adds a test wherein we engage the PCI AHCI
device and ensure that the memory region for the
HBA functionality is now accessible.

Under Q35 environments, additional PCI configuration
is performed to ensure that the HBA functionality
will become usable.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1408643079-30675-5-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Adds a specification adherence test for AHCI
where the boot-up values for the PCI configuration space
are compared against the AHCI 1.3 specification.

This test does not itself attempt to engage the device.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1408643079-30675-4-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

In the Intel ICH9 data sheet, the MSI capability offset
in the PCI configuration space for ICH9 AHCI devices is
specified to be 0x80.

Further, the PCI capability pointer should always point
to 0x80 in ICH9 devices, despite the fact that AHCI 1.3
specifies that it should be pointing to PMCAP (Which in
this instance would be 0x70) to maintain adherence to
the Intel data sheet specifications and real observed behavior.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1408643079-30675-3-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Currently, there is no qtest to test the functionality of
the AHCI functionality present within the Q35 machine type.

This patch adds a skeleton for an AHCI test suite,
and adds a simple sanity-check test case where we
identify that the AHCI device is present, then
disengage the virtual machine.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1408643079-30675-2-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Refcount structures are placed in clusters randomly selected from all
unallocated host clusters.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Maria Kustova <maria.k@catit.be>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 7e2f38608db6fba2da53997390b19400d445c45d.1408450493.git.maria.k@catit.be
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Maria Kustova <maria.k@catit.be>
Message-id: c9f4027b6f401c67e9d18f94aed29be445e81d48.1408450493.git.maria.k@catit.be
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Maria Kustova <maria.k@catit.be>
Message-id: cb71485d0f55d1d8401eebaead8324eb78673060.1408450493.git.maria.k@catit.be
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

qcow2 supports more than four options by now, add the new options
(overlap check mode and metadata cache size)

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1408557576-14574-5-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Being able to set the overlap-check option to a string and then refine
it via the overlap-check.* options is a nice idea for the command line
but does not work so well for non-flattened dicts. In that case, one can
only specify either but not both, so add a field to overlap-check.*
which does the same as directly specifying overlap-check but can be used
in conjunction with the other fields in non-flattened dicts.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1408557576-14574-4-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1408557576-14574-3-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Currently, the QemuOpts object opts is leaked if anything fails from its
creation up to and including the image repair block. Fix this by freeing
that object in the fail path.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Message-id: 1408557576-14574-2-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1410874615-14292-1-git-send-email-arei.gonglei@huawei.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Signed-off-by: Maria Kustova <maria.k@catit.be>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Add tests for unaligned L1/L2/reftable entries and non-fatal corruption
reports.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1409926039-29044-6-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Offsets taken from the L1, L2 and refcount tables are generally assumed
to be correctly aligned. However, this cannot be guaranteed if the image
has been written to by something different than qemu, thus check all
offsets taken from these tables for correct cluster alignment.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1409926039-29044-5-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Use the new function in case of a failed overlap check.

This changes output in case of corruption, so adapt iotest 060's
reference output accordingly.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Message-id: 1409926039-29044-4-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Add a helper function for easily marking an image corrupt (on fatal
corruptions) while outputting an informative message to stderr and via
QAPI.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Message-id: 1409926039-29044-3-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Not every BLOCK_IMAGE_CORRUPTED event must be fatal; for example, when
reading from an image, they should generally not be. Nonetheless, even
an image only read from may of course be corrupted and this can be
detected during normal operation. In this case, a non-fatal event should
be emitted, but the image should not be marked corrupt (in accordance to
"fatal" set to false).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1409926039-29044-2-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1410415798-20673-4-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1410415798-20673-3-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

This is an analogue to Linux null_blk. It can be used for testing or
benchmarking block device emulation and general block layer
functionalities such as coroutines and throttling, where disk IO is not
necessary or wanted.

Use null-aio:// for AIO version, and null-co:// for coroutine version.

[Resolved conflict with Fam's async bdrv_aio_cancel() series:
1. Drop .bdrv_aio_cancel() since it is now done by block.c
2. Rename qemu_aio_release() to qemu_aio_unref()
--Stefan]

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1410415798-20673-2-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

If ret is WAIT_TIMEOUT and there was an event returned by select(),
we can write to a location after the end of the array.  But in
that case we can retry the WaitForMultipleObjects call with the
same set of events, so just move the event[ret - WAIT_OBJECT_0]
assignment inside the existin conditional.

Reported-by: TeLeMan <geleman@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: TeLeMan <geleman@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>