Commit Graph

45857 Commits

Author SHA1 Message Date
Alexey Kardashevskiy
fec5d3a1cd spapr_iommu: Move table allocation to helpers
At the moment presence of vfio-pci devices on a bus affect the way
the guest view table is allocated. If there is no vfio-pci on a PHB
and the host kernel supports KVM acceleration of H_PUT_TCE, a table
is allocated in KVM. However, if there is vfio-pci and we do yet not
KVM acceleration for these, the table has to be allocated by
the userspace. At the moment the table is allocated once at boot time
but next patches will reallocate it.

This moves kvmppc_create_spapr_tce/g_malloc0 and their counterparts
to helpers.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-05-27 09:40:23 +10:00
Alexey Kardashevskiy
f94819d601 spapr_iommu: Finish renaming vfio_accel to need_vfio
6a81dd17 "spapr_iommu: Rename vfio_accel parameter" renamed vfio_accel
flag everywhere but one spot was missed.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-05-27 09:40:23 +10:00
Alexey Kardashevskiy
eded5bac3b spapr_pci: Use correct DMA LIOBN when composing the device tree
The user could have picked LIOBN via the CLI but the device tree
rendering code would still use the value derived from the PHB index
(which is the default fallback if LIOBN is not set in the CLI).

This replaces SPAPR_PCI_LIOBN() with the actual DMA LIOBN value.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-05-27 09:40:23 +10:00
Jianjun Duan
5dd5238c0b spapr: ensure device trees are always associated with DRC
There are possible racing situations involving hotplug events and
guest migration. For cases where a hotplug event is migrated, or
the guest is in the process of fetching device tree at the time of
migration, we need to ensure the device tree is created and
associated with the corresponding DRC for devices that were
hotplugged on the source, but 'coldplugged' on the target.

Signed-off-by: Jianjun Duan <duanj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-05-27 09:40:23 +10:00
Greg Kurz
41264b385c PPC/KVM: early validation of vcpu id
The KVM API restricts vcpu ids to be < KVM_CAP_MAX_VCPUS. On PowerPC
targets, depending on the number of threads per core in the host and
in the guest, some topologies do generate higher vcpu ids actually.
When this happens, QEMU bails out with the following error:

kvm_init_vcpu failed: Invalid argument

The KVM_CREATE_VCPU ioctl has several EINVAL return paths, so it is
not possible to fully disambiguate.

This patch adds a check in the code that computes vcpu ids, so that
we can detect the error earlier, and print a friendlier message instead
of calling KVM_CREATE_VCPU with an obviously bogus vcpu id.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-05-27 09:40:23 +10:00
Zhou Jie
8afc22a20f Added negative check for get_image_size()
This patch adds check for negative return value from get_image_size(),
where it is missing. It avoids unnecessary two function calls.

Signed-off-by: Zhou Jie <zhoujie2011@cn.fujitsu.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-05-27 09:40:23 +10:00
Thomas Huth
5c29dd8c28 hw/net/spapr_llan: Provide counter with dropped rx frames to the guest
The last 8 bytes of the receive buffer list page (that has been supplied
by the guest with the H_REGISTER_LOGICAL_LAN call) contain a counter
for frames that have been dropped because there was no suitable receive
buffer available. This patch introduces code to use this field to
provide the information about dropped rx packets to the guest.
There it can be queried with "ethtool -S eth0 | grep rx_no_buffer".

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-05-27 09:40:23 +10:00
Thomas Huth
8836630f5d hw/net/spapr_llan: Delay flushing of the RX queue while adding new RX buffers
Currently, the spapr-vlan device is trying to flush the RX queue
after each RX buffer that has been added by the guest via the
H_ADD_LOGICAL_LAN_BUFFER hypercall. In case the receive buffer pool
was empty before, we only pass single packets to the guest this
way. This can cause very bad performance if a sender is trying
to stream fragmented UDP packets to the guest. For example when
using the UDP_STREAM test from netperf with UDP packets that are
much bigger than the MTU size, almost all UDP packets are dropped
in the guest since the chances are quite high that at least one of
the fragments got lost on the way.

When flushing the receive queue, it's much better if we'd have
a bunch of receive buffers available already, so that fragmented
packets can be passed to the guest in one go. To do this, the
spapr_vlan_receive() function should return 0 instead of -1 if there
are no more receive buffers available, so that receive_disabled = 1
gets temporarily set for the receive queue, and we have to delay
the queue flushing at the end of h_add_logical_lan_buffer() a little
bit by using a timer, so that the guest gets a chance to add multiple
RX buffers before we flush the queue again.

This improves the UDP_STREAM test with the spapr-vlan device a lot:
Running
 netserver -p 44444 -L <guestip> -f -D -4
in the guest, and
 netperf -p 44444 -L <hostip> -H <guestip> -t UDP_STREAM -l 60 -- -m 16384
in the host, I get the following values _without_ this patch:

Socket  Message  Elapsed      Messages
Size    Size     Time         Okay Errors   Throughput
bytes   bytes    secs            #      #   10^6bits/sec

229376   16384   60.00     1738970      0    3798.83
229376           60.00          23              0.05

That "0.05" means that almost all UDP packets got lost/discarded
at the receiving side.
With this patch applied, the value look much better:

Socket  Message  Elapsed      Messages
Size    Size     Time         Okay Errors   Throughput
bytes   bytes    secs            #      #   10^6bits/sec

229376   16384   60.00     1789104      0    3908.35
229376           60.00       22818             49.85

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-05-27 09:40:22 +10:00
Richard Henderson
a7b2c8b90a target-ppc: Cleanups to rldinm, rldnm, rldimi
Mirror the cleanups just done to rlwinm, rlwnm and rlwimi.
This adds use of deposit to rldimi.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-05-27 09:40:22 +10:00
Richard Henderson
63ae0915f8 target-ppc: Use 32-bit rotate instead of deposit + 64-bit rotate
A 32-bit rotate insn is more common on hosts than a deposit insn,
and if the host has neither the result is truely horrific.

At the same time, tidy up the temporaries within these functions,
drop the over-use of "likely", drop some checks for identity that
will also be checked by tcg-op.c functions, and special case mask
without rotate within rlwinm.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-05-27 09:40:22 +10:00
Richard Henderson
24f9cd951d target-ppc: Use movcond in isel
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-05-27 09:40:22 +10:00
David Gibson
319de6fe6e target-ppc: Correct KVM synchronization for ppc_hash64_set_external_hpt()
ppc_hash64_set_external_hpt() was added in e5c0d3c "target-ppc: Add helpers
for updating a CPU's SDR1 and external HPT".  This helper contains a
cpu_synchronize_state() since it may need to push state back to KVM
afterwards.

This turns out to break things when it is used in the reset path, which is
the only current user.  It appears that kvm_vcpu_dirty is not being set
early in the reset path, so the cpu_synchronize_state() is clobbering state
set up by the early part of the cpu reset path with stale state from KVM.

This may require some changes to the generic cpu reset path to fix
properly, but as a short term fix we can just remove the
cpu_synchronize_state() from ppc_hash64_set_external_hpt(), and require any
non-reset path callers to do that manually.

Reported-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-05-27 09:40:22 +10:00
Peter Maydell
84cfc756d1 VFIO updates 2016-05-26
- Infrastructure and quirks to support IGD assignment (Alex Williamson)
  - Fixes to 128bit handling, IOMMU replay, IOMMU translation sanity
    checking (Alexey Kardashevskiy)
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.14 (GNU/Linux)
 
 iQIcBAABAgAGBQJXRzdlAAoJECObm247sIsiPcoP/Ay3xXIkMgef1cWpxeVn+MV6
 02/fEWOHf54LMMEkJJZujFh7n9s6fDJXaNOsdHxPyxbGf+enJyEFGWG8THne3N3G
 jsKEjjgpP70f19oLEOMfnK2n4vRPXmkFgSMQJcCjwoeHcwjzfbczixkwh1Y0Qxwo
 QD1pqp/yXefyP8TaanzTHqv/ED4McqBAJpoTZ8CvcDeHNhTatoCQj8kNhgY3sIWm
 25f2GNFrpHYpRulgcxvBt5CaiCfUvz9qU2z/Y0XaPfRQ5KvDM8wNQXj5TITrotkF
 jVqXRKs+vMlPF/+HeBZNjVGS4dJAJwqukWRDgcQ2mfNlbuPUyDEL8HaD/shS8QjT
 agL60D9duScTfHU1wqyWEnUiBT/IbJG9oHWyYuVSRvW13muAlvLx4gKONss8WL7+
 RqmSNqhEyZHqPRkoqhiCdVn/+quR56rz7uS0mlazMFVZ7ABA19W7BLWxLIylkLQN
 xrvVWlBtM+Fun9UIcxJnGX7o16RzMqczeRgtBgblWtHStnKAzBC+mjwhqZ+vOXt8
 S8YXn4g/+FWjO4RRvHKuROFALFpwT3BfqjzZgZcNf6ve4s7n2Dn9d81UbO61TLgw
 /DZS62C95WLQhA6nBJksxwrpkQ6JHA5HikzwBRE9iQgyEGlAR51xqOM71h1Wxp8p
 qzaiYlMQx1btYdc/A+xU
 =in4A
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/awilliam/tags/vfio-update-20160526.1' into staging

VFIO updates 2016-05-26

 - Infrastructure and quirks to support IGD assignment (Alex Williamson)
 - Fixes to 128bit handling, IOMMU replay, IOMMU translation sanity
   checking (Alexey Kardashevskiy)

# gpg: Signature made Thu 26 May 2016 18:50:29 BST using RSA key ID 3BB08B22
# 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>"

* remotes/awilliam/tags/vfio-update-20160526.1:
  vfio: Check that IOMMU MR translates to system address space
  memory: Fix IOMMU replay base address
  vfio: Fix 128 bit handling when deleting region
  vfio/pci: Add IGD documentation
  vfio/pci: Add a separate option for IGD OpRegion support
  vfio/pci: Intel graphics legacy mode assignment
  vfio/pci: Setup BAR quirks after capabilities probing
  vfio/pci: Consolidate VGA setup
  vfio/pci: Fix return of vfio_populate_vga()
  vfio: Create device specific region info helper
  vfio: Enable sparse mmap capability

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-26 19:18:08 +01:00
Alexey Kardashevskiy
f1f9365019 vfio: Check that IOMMU MR translates to system address space
At the moment IOMMU MR only translate to the system memory.
However if some new code changes this, we will need clear indication why
it is not working so here is the check.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-05-26 11:12:09 -06:00
Alexey Kardashevskiy
d78c19b5cf memory: Fix IOMMU replay base address
Since a788f227 "memory: Allow replay of IOMMU mapping notifications"
when new VFIO listener is added, all existing IOMMU mappings are
replayed. However there is a problem that the base address of
an IOMMU memory region (IOMMU MR) is ignored which is not a problem
for the existing user (which is pseries) with its default 32bit DMA
window starting at 0 but it is if there is another DMA window.

This stores the IOMMU's offset_within_address_space and adjusts
the IOVA before calling vfio_dma_map/vfio_dma_unmap.

As the IOMMU notifier expects IOVA offset rather than the absolute
address, this also adjusts IOVA in sPAPR H_PUT_TCE handler before
calling notifier(s).

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-05-26 11:12:08 -06:00
Alexey Kardashevskiy
7a057b4fb9 vfio: Fix 128 bit handling when deleting region
7532d3cbf "vfio: Fix 128 bit handling" added support for 64bit IOMMU
memory regions when those are added to VFIO address space; however
removing code cannot cope with these as int128_get64() will fail on
1<<64.

This copies 128bit handling from region_add() to region_del().

Since the only machine type which is actually going to use 64bit IOMMU
is pseries and it never really removes them (instead it will dynamically
add/remove subregions), this should cause no behavioral change.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-05-26 11:12:07 -06:00
Alex Williamson
0eb7342417 vfio/pci: Add IGD documentation
Document the usage modes, host primary graphics considerations, usage,
and fw_cfg ABI required for IGD assignment with vfio.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-26 11:12:05 -06:00
Alex Williamson
6ced0bba70 vfio/pci: Add a separate option for IGD OpRegion support
The IGD OpRegion is enabled automatically when running in legacy mode,
but it can sometimes be useful in universal passthrough mode as well.
Without an OpRegion, output spigots don't work, and even though Intel
doesn't officially support physical outputs in UPT mode, it's a
useful feature.  Note that if an OpRegion is enabled but a monitor is
not connected, some graphics features will be disabled in the guest
versus a headless system without an OpRegion, where they would work.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-26 11:12:03 -06:00
Alex Williamson
c4c45e943e vfio/pci: Intel graphics legacy mode assignment
Enable quirks to support SandyBridge and newer IGD devices as primary
VM graphics.  This requires new vfio-pci device specific regions added
in kernel v4.6 to expose the IGD OpRegion, the shadow ROM, and config
space access to the PCI host bridge and LPC/ISA bridge.  VM firmware
support, SeaBIOS only so far, is also required for reserving memory
regions for IGD specific use.  In order to enable this mode, IGD must
be assigned to the VM at PCI bus address 00:02.0, it must have a ROM,
it must be able to enable VGA, it must have or be able to create on
its own an LPC/ISA bridge of the proper type at PCI bus address
00:1f.0 (sorry, not compatible with Q35 yet), and it must have the
above noted vfio-pci kernel features and BIOS.  The intention is that
to enable this mode, a user simply needs to assign 00:02.0 from the
host to 00:02.0 in the VM:

  -device vfio-pci,host=0000:00:02.0,bus=pci.0,addr=02.0

and everything either happens automatically or it doesn't.  In the
case that it doesn't, we leave error reports, but assume the device
will operate in universal passthrough mode (UPT), which doesn't
require any of this, but has a much more narrow window of supported
devices, supported use cases, and supported guest drivers.

When using IGD in this mode, the VM firmware is required to reserve
some VM RAM for the OpRegion (on the order or several 4k pages) and
stolen memory for the GTT (up to 8MB for the latest GPUs).  An
additional option, x-igd-gms allows the user to specify some amount
of additional memory (value is number of 32MB chunks up to 512MB) that
is pre-allocated for graphics use.  TBH, I don't know of anything that
requires this or makes use of this memory, which is why we don't
allocate any by default, but the specification suggests this is not
actually a valid combination, so the option exists as a workaround.
Please report if it's actually necessary in some environment.

See code comments for further discussion about the actual operation
of the quirks necessary to assign these devices.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-26 11:12:01 -06:00
Alex Williamson
581406e0e3 vfio/pci: Setup BAR quirks after capabilities probing
Capability probing modifies wmask, which quirks may be interested in
changing themselves.  Apply our BAR quirks after the capability scan
to make this possible.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-26 11:12:00 -06:00
Alex Williamson
182bca4592 vfio/pci: Consolidate VGA setup
Combine VGA discovery and registration.  Quirks can have dependencies
on BARs, so the quirks push out until after we've scanned the BARs.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-26 11:11:58 -06:00
Alex Williamson
4225f2b670 vfio/pci: Fix return of vfio_populate_vga()
This function returns success if either we setup the VGA region or
the host vfio doesn't return enough regions to support the VGA index.
This latter case doesn't make any sense.  If we're asked to populate
VGA, fail if it doesn't exist and let the caller decide if that's
important.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-26 11:11:56 -06:00
Alex Williamson
e61a424f05 vfio: Create device specific region info helper
Given a device specific region type and sub-type, find it.  Also
cleanup return point on error in vfio_get_region_info() so that we
always return 0 with a valid pointer or -errno and NULL.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-26 11:04:50 -06:00
Alex Williamson
b53b0f696b vfio: Enable sparse mmap capability
The sparse mmap capability in a vfio region info allows vfio to tell
us which sub-areas of a region may be mmap'd.  Thus rather than
assuming a single mmap covers the entire region and later frobbing it
ourselves for things like the PCI MSI-X vector table, we can read that
directly from vfio.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-26 09:43:20 -06:00
Peter Maydell
aef11b8d33 migration: add TLS support to the migration data channel
This is a big refactoring of the migration backend code - moving away from
 QEMUFile to the new QIOChannel framework introduced here.  This brings a
 good level of abstraction and reduction of many lines of code.
 
 This series also adds the ability for many backends (all except RDMA) to
 use TLS for encrypting the migration data between the endpoints.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQIcBAABCAAGBQJXRpKMAAoJEOsLTfxlfvZw2FMQAJmrp8ijvJNtdBa51bNY+xVx
 zvrHDpWco/HxxqyBIGxG7g8Iq+wpNsdgoRxoQkfgIz9RkZiNrzb1kGRiqNFFBKFX
 ziK1QQQ12ETUXwQ6VguBuwLDvCCenyUti0HfKkceG+Zu5263fyp+VzL+PuEtteT3
 M0pZRrifj/TQqCBXR8yhBAo2dCiFETLVoruE+iNg2ipI3JDizxy8bdOU2gfnTayf
 na7lE53pI+Wy8KE+qrhtsEgjHFp48uJ0HwQIIumvVndXFpIhRzCcN/aeVCjNYRjo
 GeI18OJxcimRDwsnfuOwuZKhRcjWfa8WEIKsi8LdRTZFpFL6y9R57XNTBIFfbjOF
 0lkmFTqJTBi3OTPjj0hMjpjOfXhyKUnwdqCAYlAxeuWHhqPDDhtEcnNtGdmQzx4Z
 KvYzc3t31o1gPin024UUfA528PNREszaXhTM90/Dj0dhVSMoG1VQsQjxzkPXxdM1
 wemfic+77Bk4oUrSplhdvvk4nySDWeseEjfdyVU2ixqldy8Ib1+6H+PCjWNotpQ0
 YiDOHBy3rrUh6NhIqb0C2PWvd/9Aqs0nHQHJ8QKYK574MDbVo8mKTACFdoSYoZ1u
 wuif7NL6qkyS55szf0dm8zPBCJ5nIR5SQE98E7+ptXNa8AipfFsTkZrr3aOjcdey
 98AWF9KaZOWRfwgIm3Ft
 =AYEK
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/amit-migration/tags/migration-2.7-2' into staging

migration: add TLS support to the migration data channel

This is a big refactoring of the migration backend code - moving away from
QEMUFile to the new QIOChannel framework introduced here.  This brings a
good level of abstraction and reduction of many lines of code.

This series also adds the ability for many backends (all except RDMA) to
use TLS for encrypting the migration data between the endpoints.

# gpg: Signature made Thu 26 May 2016 07:07:08 BST using RSA key ID 657EF670
# gpg: Good signature from "Amit Shah <amit@amitshah.net>"
# gpg:                 aka "Amit Shah <amit@kernel.org>"
# gpg:                 aka "Amit Shah <amitshah@gmx.net>"

* remotes/amit-migration/tags/migration-2.7-2: (28 commits)
  migration: remove qemu_get_fd method from QEMUFile
  migration: remove support for non-iovec based write handlers
  migration: add support for encrypting data with TLS
  migration: define 'tls-creds' and 'tls-hostname' migration parameters
  migration: don't use an array for storing migrate parameters
  migration: move definition of struct QEMUFile back into qemu-file.c
  migration: delete QEMUFile stdio implementation
  migration: delete QEMUFile sockets implementation
  migration: delete QEMUSizedBuffer struct
  migration: delete QEMUFile buffer implementation
  migration: convert savevm to use QIOChannel for writing to files
  migration: convert RDMA to use QIOChannel interface
  migration: convert exec socket protocol to use QIOChannel
  migration: convert fd socket protocol to use QIOChannel
  migration: convert tcp socket protocol to use QIOChannel
  migration: rename unix.c to socket.c
  migration: convert unix socket protocol to use QIOChannel
  migration: convert post-copy to use QIOChannelBuffer
  migration: add reporting of errors for outgoing migration
  migration: add helpers for creating QEMUFile from a QIOChannel
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-26 16:09:27 +01:00
Peter Maydell
2c56d06baf Block layer patches
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQIcBAABAgAGBQJXReG4AAoJEH8JsnLIjy/WKv0P/0Bevm3ahvJuStRdl+u0MgZ7
 9jM69CN3wxH8SVwCJ3zBndWVOrsAbXB+SFTu/0Dr+tq+dw901AN8lspzf1TFiYnL
 5M8B1syjOXUxuOcwl18ytuDu9aQhxbbCIC9pzWqxizm8N2nXP9r/VlNiztm4T2nn
 RV0DyD5XVoV2v3rpFPerv1EgOtO0lmfgSABwk31a5ftULdy1QzDOliLm/l7W7Oke
 xMFJ93OOBd/p0jmLrULM3V/tipRpxcnvijfVoLJb3895/0G7mJ1PCRYl3uokd+cy
 DxmWw9Fil/kfpwmQhpvpWeOeSkh/NXVNDH5fLfl7V1dPyYcs2xZOJz3mNtuMDU2N
 kBxkWtOQivr/q9cIK6sEacDRtTjouRi/DoccR6S8IXs9nY1fJoLBvXufo2mQrwsy
 5heUhrvZ+AD/eZVjQXQyIc9jCLltU12lW1Z+KrVO7HICcT/Z+UGqeROrRrhzjRRl
 iuO2iHXI7I4KSB2Xgrx5WMYZu8GbxHJmfe20O2bupJ5PHRHLF0ySZ0MW3Gbs1W5E
 5e5tU4D4x5JYJ1KYsMg2FsuejqMBh25coqywT7I3XOEOnN8opOPVKoHb86gZOjXD
 wckrSGHkX9rfvRgy+vG/d3RqQOvxtaH1kbWCHikVjHpnVPzz6uPPD1H8/T5s2IGB
 49PdfL0SIOQsl9U/3WPk
 =g40O
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches

# gpg: Signature made Wed 25 May 2016 18:32:40 BST using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"

* remotes/kevin/tags/for-upstream: (31 commits)
  blockjob: Remove BlockJob.bs
  commit: Use BlockBackend for I/O
  backup: Use BlockBackend for I/O
  backup: Remove bs parameter from backup_do_cow()
  backup: Pack Notifier within BackupBlockJob
  backup: Don't leak BackupBlockJob in error path
  mirror: Use BlockBackend for I/O
  mirror: Allow target that already has a BlockBackend
  stream: Use BlockBackend for I/O
  block: Make blk_co_preadv/pwritev() public
  block: Convert block job core to BlockBackend
  block: Default to enabled write cache in blk_new()
  block: Cancel jobs first in bdrv_close_all()
  block: keep a list of block jobs
  block: Rename blk_write_zeroes()
  dma-helpers: change BlockBackend to opaque value in DMAIOFunc
  dma-helpers: change interface to byte-based
  block: Propagate .drained_begin/end callbacks
  block: Fix reconfiguring graph with drained nodes
  block: Make bdrv_drain() use bdrv_drained_begin/end()
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-26 14:29:30 +01:00
Andreas Färber
a62c89117f qdev: Start disentangling bus from device
Move bus type and related APIs to a separate file bus.c.
This is a first step in breaking up qdev.c into more manageable chunks.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[AF: Rebased onto osdep.h]
Signed-off-by: Andreas Färber <afaerber@suse.de>
[PMM: added bus.o to link line for test-qdev-global-props]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-26 14:06:41 +01:00
Sergey Fedorov
c88c67e58b cpu-exec: Fix direct jump to TB spanning page
It is not safe to make a direct jump to a TB spanning two pages in
system emulation because the mapping for the second page can get changed
but we don't take care of direct jumps in this case.

However in user mode emulation, this is not the case because there's
only static address translation and TBs are always invalidated properly.

Fixes: 5b053a4a28 ("tcg: Clean up direct block chaining safety checks")

Reported-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Tested-by: Max Filippov <jcmvbkbc@gmail.com>
Message-id: 1463404380-29302-1-git-send-email-sergey.fedorov@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-26 13:14:29 +01:00
Peter Maydell
0533d3de60 Andreas stepping down from most maintainer positions
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQIcBAABAgAGBQJXRcqJAAoJEPou0S0+fgE/a00QAIWVINu7rN6Pv9RrbkmaNoan
 geKyY1urljB6v8vkGeuYGAkmWXxLcvrduXTHh+b8MD8MxokzulL11ftxd1/5Oldj
 v9I+4XSbO5I/cw8OxFxf8vsxBRox+XckeFdm3Ft0pEFXd2lZsK4WRnqZ0lG2p0D2
 j2TXzngwiIpvtoL6Gm14dBJc0bvDxJ+JLMFNvViMMqABwrLb/kMHYm0zx6OUrIO7
 K5NCfCZCkIYJ4eRRcH/o0YKotvGGabfeqOWQ+4aPmnYp/DlunfzAb6ex7GujzSvE
 DjsD+hI63FkOTs8ZtV/YFqbTN1Rp139WnVD7f0HYPCP2DK8a1OMNlAJ4ZRl08jS4
 UOmM6NJJ+op1XESfwqJ8aXsOL6Gm4dhErHQ8yPJFWvzrO2IxYU5J4NnRNDrqJZBR
 U2+X67ZIYYviBCCAYZyssaIcCS7tTG8wo6sTQXEeXpuc+94e2X1hQJEXqFn3N89X
 0DpOFz0+FE63Xdj3nOHeDTxYZI6j6v0L2eQ8YPEEm5RQJSaOGGk/u128+6IjP6VC
 63T1bwLlY5ZKffNgS8XaywRGAKSQJp0woNOxy6a5zc7R8Ns6QP0IGEKFzs6kOdiI
 NYB4nK/NAZHu8uBNrcKXiqkwS9LDOqJflXynboyWKYmbkgu8pqj03aN5L1pBQCis
 8tL2eL+340zkqhN31PTQ
 =AMGu
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/afaerber/tags/maintainers-for-peter' into staging

Andreas stepping down from most maintainer positions

# gpg: Signature made Wed 25 May 2016 16:53:45 BST using RSA key ID 3E7E013F
# gpg: Good signature from "Andreas Färber <afaerber@suse.de>"
# gpg:                 aka "Andreas Färber <afaerber@suse.com>"

* remotes/afaerber/tags/maintainers-for-peter:
  MAINTAINERS: Drop Andreas as CPU maintainer
  MAINTAINERS: Drop Andreas as 0.15 maintainer
  MAINTAINERS: Drop Andreas as PReP maintainer
  MAINTAINERS: Drop Andreas as Cocoa maintainer

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-26 12:41:12 +01:00
Daniel P. Berrange
12992c16d9 migration: remove qemu_get_fd method from QEMUFile
Now that there is a set_blocking callback in QEMUFileOps,
and all users needing non-blocking support have been
converted to QIOChannel, there is no longer any codepath
requiring the qemu_get_fd() method for QEMUFile. Remove it
to avoid further code being introduced with an expectation
of direct file handle access.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-29-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:21 +05:30
Daniel P. Berrange
11808bb0c4 migration: remove support for non-iovec based write handlers
All the remaining QEMUFile implementations provide an iovec
based write handler, so the put_buffer callback can be removed
to simplify the code.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-28-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:18 +05:30
Daniel P. Berrange
e122636562 migration: add support for encrypting data with TLS
This extends the migration_set_incoming_channel and
migration_set_outgoing_channel methods so that they
will automatically wrap the QIOChannel in a
QIOChannelTLS instance if TLS credentials are configured
in the migration parameters.

This allows TLS to work for tcp, unix, fd and exec
migration protocols. It does not (currently) work for
RDMA since it does not use these APIs, but it is
unlikely that TLS would be desired with RDMA anyway
since it would degrade the performance to that seen
with TCP defeating the purpose of using RDMA.

On the target host, QEMU would be launched with a set
of TLS credentials for a server endpoint

 $ qemu-system-x86_64 -monitor stdio -incoming defer \
    -object tls-creds-x509,dir=/home/berrange/security/qemutls,endpoint=server,id=tls0 \
    ...other args...

To enable incoming TLS migration 2 monitor commands are
then used

  (qemu) migrate_set_str_parameter tls-creds tls0
  (qemu) migrate_incoming tcp:myhostname:9000

On the source host, QEMU is launched in a similar
manner but using client endpoint credentials

 $ qemu-system-x86_64 -monitor stdio \
    -object tls-creds-x509,dir=/home/berrange/security/qemutls,endpoint=client,id=tls0 \
    ...other args...

To enable outgoing TLS migration 2 monitor commands are
then used

  (qemu) migrate_set_str_parameter tls-creds tls0
  (qemu) migrate tcp:otherhostname:9000

Thanks to earlier improvements to error reporting,
TLS errors can be seen 'info migrate' when doing a
detached migration. For example:

  (qemu) info migrate
  capabilities: xbzrle: off rdma-pin-all: off auto-converge: off zero-blocks: off compress: off events: off x-postcopy-ram: off
  Migration status: failed
  total time: 0 milliseconds
  error description: TLS handshake failed: The TLS connection was non-properly terminated.

Or

  (qemu) info migrate
  capabilities: xbzrle: off rdma-pin-all: off auto-converge: off zero-blocks: off compress: off events: off x-postcopy-ram: off
  Migration status: failed
  total time: 0 milliseconds
  error description: Certificate does not match the hostname localhost

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-27-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:13 +05:30
Daniel P. Berrange
69ef1f36b0 migration: define 'tls-creds' and 'tls-hostname' migration parameters
Define two new migration parameters to be used with TLS encryption.
The 'tls-creds' parameter provides the ID of an instance of the
'tls-creds' object type, or rather a subclass such as 'tls-creds-x509'.
Providing these credentials will enable use of TLS on the migration
data stream.

If using x509 certificates, together with a migration URI that does
not include a hostname, the 'tls-hostname' parameter provides the
hostname to use when verifying the server's x509 certificate. This
allows TLS to be used in combination with fd: and exec: protocols
where a TCP connection is established by a 3rd party outside of
QEMU.

NB, this requires changing the migrate_set_parameter method in the
HMP to accept a 's' (string) value instead of 'i' (integer). This
is backwards compatible, because the parsing of strings allows the
quotes to be optional, thus any integer is also a valid string.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-26-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:10 +05:30
Daniel P. Berrange
2594f56d4c migration: don't use an array for storing migrate parameters
The MigrateState struct uses an array for storing migration
parameters. This presumes that all future parameters will
be integers too, which is not going to be the case. There
is no functional reason why an array is used, if anything
it makes the code less clear. The QAPI schema already
defines a struct - MigrationParameters - capable of storing
all the individual parameters, so just use that instead of
an array.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-25-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:07 +05:30
Daniel P. Berrange
a24939f279 migration: move definition of struct QEMUFile back into qemu-file.c
Now that the memory buffer based QEMUFile impl is gone, there
is no need for any backend to be accessing internals of the
QEMUFile struct, so it can be moved back into qemu-file.c

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-24-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:05 +05:30
Daniel P. Berrange
7fdc61c75d migration: delete QEMUFile stdio implementation
Now that the exec migration backend and savevm have converted
to use the QIOChannel based QEMUFile, there is no user remaining
for the stdio based QEMUFile impl and it can be deleted.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-23-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:03 +05:30
Daniel P. Berrange
40946ae40b migration: delete QEMUFile sockets implementation
Now that the tcp, unix and fd migration backends have converted
to use the QIOChannel based QEMUFile, there is no user remaining
for the sockets based QEMUFile impl and it can be deleted.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-22-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:00 +05:30
Daniel P. Berrange
2a22b4f370 migration: delete QEMUSizedBuffer struct
Now that we don't have have a buffer based QemuFile
implementation, the QEMUSizedBuffer code is also
unused and can be deleted. A simpler buffer class
also exists in util/buffer.c which other code can
used as needed.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-21-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:58 +05:30
Daniel P. Berrange
8b7c5c0f52 migration: delete QEMUFile buffer implementation
The qemu_bufopen() method is no longer used, so the memory
buffer based QEMUFile backend can be deleted entirely.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-20-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:55 +05:30
Daniel P. Berrange
8925839f00 migration: convert savevm to use QIOChannel for writing to files
Convert the exec savevm code to use QIOChannel and QEMUFileChannel,
instead of the stdio APIs.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-19-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:53 +05:30
Daniel P. Berrange
6ddd2d76ca migration: convert RDMA to use QIOChannel interface
This converts the RDMA code to provide a subclass of QIOChannel
that uses RDMA for the data transport.

This implementation of RDMA does not correctly handle non-blocking
mode. Reads might block if there was not already some pending data
and writes will block until all data is sent. This flawed behaviour
was already present in the existing impl, so appears to not be a
critical problem at this time. It should be on the list of things
to fix in the future though.

The RDMA code would be much better off it it could be split up in
a generic RDMA layer, a QIOChannel impl based on RMDA, and then
the RMDA migration glue. This is left as a future exercise for
the brave.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-18-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:50 +05:30
Daniel P. Berrange
527792fae6 migration: convert exec socket protocol to use QIOChannel
Convert the exec socket migration protocol driver to use
QIOChannel and QEMUFileChannel, instead of the stdio
popen APIs. It can be unconditionally built because the
QIOChannelCommand class can report suitable error messages
on platforms which can't fork processes.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-17-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:47 +05:30
Daniel P. Berrange
64802ee57f migration: convert fd socket protocol to use QIOChannel
Convert the fd socket migration protocol driver to use
QIOChannel and QEMUFileChannel, instead of plain sockets
APIs. It can be unconditionally built because the
QIOChannel APIs it uses will take care to report suitable
error messages if needed.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-16-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:45 +05:30
Daniel P. Berrange
e65c67e4da migration: convert tcp socket protocol to use QIOChannel
Drop the current TCP socket migration driver and extend
the new generic socket driver to cope with the TCP address
format

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-15-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:42 +05:30
Daniel P. Berrange
6f860ae755 migration: rename unix.c to socket.c
The unix.c file will be nearly the same as the tcp.c file,
only differing in the initial SocketAddress creation code.
Rename unix.c to socket.c and refactor it a little to
prepare for merging the TCP code.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-14-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:40 +05:30
Daniel P. Berrange
d984464eb9 migration: convert unix socket protocol to use QIOChannel
Convert the unix socket migration protocol driver to use
QIOChannel and QEMUFileChannel, instead of plain sockets
APIs. It can be unconditionally built, since the socket
impl of QIOChannel will report a suitable error on platforms
where UNIX sockets are unavailable.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-13-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:37 +05:30
Daniel P. Berrange
61b67d473d migration: convert post-copy to use QIOChannelBuffer
The post-copy code does some I/O to/from an intermediate
in-memory buffer rather than direct to the underlying
I/O channel. Switch this code to use QIOChannelBuffer
instead of QEMUSizedBuffer.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-12-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:34 +05:30
Daniel P. Berrange
d59ce6f344 migration: add reporting of errors for outgoing migration
Currently if an application initiates an outgoing migration,
it may or may not, get an error reported back on failure. If
the error occurs synchronously to the 'migrate' command
execution, the client app will see the error message. This
is the case for DNS lookup failures. If the error occurs
asynchronously to the monitor command though, the error
will be thrown away and the client left guessing about
what went wrong. This is the case for failure to connect
to the TCP server (eg due to wrong port, or firewall
rules, or other similar errors).

In the future we'll be adding more scope for errors to
happen asynchronously with the TLS protocol handshake.
TLS errors are hard to diagnose even when they are well
reported, so discarding errors entirely will make it
impossible to debug TLS connection problems.

Management apps which do migration are already using
'query-migrate' / 'info migrate' to check up on progress
of background migration operations and to see their end
status. This is a fine place to also include the error
message when things go wrong.

This patch thus adds an 'error-desc' field to the
MigrationInfo struct, which will be populated when
the 'status' is set to 'failed':

(qemu) migrate -d tcp:localhost:9001
(qemu) info migrate
capabilities: xbzrle: off rdma-pin-all: off auto-converge: off zero-blocks: off compress: off events: off x-postcopy-ram: off
Migration status: failed (Error connecting to socket: Connection refused)
total time: 0 milliseconds

In the HMP, when doing non-detached migration, it is
also possible to display this error message directly
to the app.

(qemu) migrate tcp:localhost:9001
Error connecting to socket: Connection refused

Or with QMP

  {
    "execute": "query-migrate",
    "arguments": {}
  }
  {
    "return": {
      "status": "failed",
      "error-desc": "address resolution failed for myhost:9000: No address associated with hostname"
    }
  }

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1461751518-12128-11-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:30 +05:30
Daniel P. Berrange
48f07489ed migration: add helpers for creating QEMUFile from a QIOChannel
Currently creating a QEMUFile instance from a QIOChannel is
quite simple only requiring a single call to
qemu_fopen_channel_input or  qemu_fopen_channel_output
depending on the end of migration connection.

When QEMU gains TLS support, however, there will need to be
a TLS negotiation done inbetween creation of the QIOChannel
and creation of the final QEMUFile. Introduce some helper
methods that will encapsulate this logic, isolating the
migration protocol drivers from knowledge about TLS.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Acked-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1461751518-12128-10-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:27 +05:30
Daniel P. Berrange
a9cfeb33bb migration: introduce a new QEMUFile impl based on QIOChannel
Introduce a new QEMUFile implementation that is based on
the QIOChannel objects. This impl is different from existing
impls in that there is no file descriptor that can be made
available, as some channels may be based on higher level
protocols such as TLS.

Although the QIOChannel based implementation can trivially
provide a bi-directional stream, initially we have separate
functions for opening input & output directions to fit with
the expectation of the current QEMUFile interface.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-9-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:24 +05:30