<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/drivers/xen, branch v4.9-rc2</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'for-linus-4.9-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip</title>
<updated>2016-10-06T18:19:10+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-10-06T18:19:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=541efb7632642cab55361178d73d544f025b593c'/>
<id>541efb7632642cab55361178d73d544f025b593c</id>
<content type='text'>
Pull xen updates from David Vrabel:
 "xen features and fixes for 4.9:

   - switch to new CPU hotplug mechanism

   - support driver_override in pciback

   - require vector callback for HVM guests (the alternate mechanism via
     the platform device has been broken for ages)"

* tag 'for-linus-4.9-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/x86: Update topology map for PV VCPUs
  xen/x86: Initialize per_cpu(xen_vcpu, 0) a little earlier
  xen/pciback: support driver_override
  xen/pciback: avoid multiple entries in slot list
  xen/pciback: simplify pcistub device handling
  xen: Remove event channel notification through Xen PCI platform device
  xen/events: Convert to hotplug state machine
  xen/x86: Convert to hotplug state machine
  x86/xen: add missing \n at end of printk warning message
  xen/grant-table: Use kmalloc_array() in arch_gnttab_valloc()
  xen: Make VPMU init message look less scary
  xen: rename xen_pmu_init() in sys-hypervisor.c
  hotplug: Prevent alloc/free of irq descriptors during cpu up/down (again)
  xen/x86: Move irq allocation from Xen smp_op.cpu_up()
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull xen updates from David Vrabel:
 "xen features and fixes for 4.9:

   - switch to new CPU hotplug mechanism

   - support driver_override in pciback

   - require vector callback for HVM guests (the alternate mechanism via
     the platform device has been broken for ages)"

* tag 'for-linus-4.9-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/x86: Update topology map for PV VCPUs
  xen/x86: Initialize per_cpu(xen_vcpu, 0) a little earlier
  xen/pciback: support driver_override
  xen/pciback: avoid multiple entries in slot list
  xen/pciback: simplify pcistub device handling
  xen: Remove event channel notification through Xen PCI platform device
  xen/events: Convert to hotplug state machine
  xen/x86: Convert to hotplug state machine
  x86/xen: add missing \n at end of printk warning message
  xen/grant-table: Use kmalloc_array() in arch_gnttab_valloc()
  xen: Make VPMU init message look less scary
  xen: rename xen_pmu_init() in sys-hypervisor.c
  hotplug: Prevent alloc/free of irq descriptors during cpu up/down (again)
  xen/x86: Move irq allocation from Xen smp_op.cpu_up()
</pre>
</div>
</content>
</entry>
<entry>
<title>xen/pciback: support driver_override</title>
<updated>2016-09-30T10:49:02+00:00</updated>
<author>
<name>Juergen Gross</name>
<email>jgross@suse.com</email>
</author>
<published>2016-09-22T08:45:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b057878b2aadc7e06280e7e702a36e7adb1bcdf7'/>
<id>b057878b2aadc7e06280e7e702a36e7adb1bcdf7</id>
<content type='text'>
Support the driver_override scheme introduced with commit 782a985d7af2
("PCI: Introduce new device binding path using pci_dev.driver_override")

As pcistub_probe() is called for all devices (it has to check for a
match based on the slot address rather than device type) it has to
check for driver_override set to "pciback" itself.

Up to now for assigning a pci device to pciback you need something like:

echo 0000:07:10.0 &gt; /sys/bus/pci/devices/0000\:07\:10.0/driver/unbind
echo 0000:07:10.0 &gt; /sys/bus/pci/drivers/pciback/new_slot
echo 0000:07:10.0 &gt; /sys/bus/pci/drivers_probe

while with the patch you can use the same mechanism as for similar
drivers like pci-stub and vfio-pci:

echo pciback &gt; /sys/bus/pci/devices/0000\:07\:10.0/driver_override
echo 0000:07:10.0 &gt; /sys/bus/pci/devices/0000\:07\:10.0/driver/unbind
echo 0000:07:10.0 &gt; /sys/bus/pci/drivers_probe

So e.g. libvirt doesn't need special handling for pciback.

Signed-off-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: David Vrabel &lt;david.vrabel@citrix.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Support the driver_override scheme introduced with commit 782a985d7af2
("PCI: Introduce new device binding path using pci_dev.driver_override")

As pcistub_probe() is called for all devices (it has to check for a
match based on the slot address rather than device type) it has to
check for driver_override set to "pciback" itself.

Up to now for assigning a pci device to pciback you need something like:

echo 0000:07:10.0 &gt; /sys/bus/pci/devices/0000\:07\:10.0/driver/unbind
echo 0000:07:10.0 &gt; /sys/bus/pci/drivers/pciback/new_slot
echo 0000:07:10.0 &gt; /sys/bus/pci/drivers_probe

while with the patch you can use the same mechanism as for similar
drivers like pci-stub and vfio-pci:

echo pciback &gt; /sys/bus/pci/devices/0000\:07\:10.0/driver_override
echo 0000:07:10.0 &gt; /sys/bus/pci/devices/0000\:07\:10.0/driver/unbind
echo 0000:07:10.0 &gt; /sys/bus/pci/drivers_probe

So e.g. libvirt doesn't need special handling for pciback.

Signed-off-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: David Vrabel &lt;david.vrabel@citrix.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>xen/pciback: avoid multiple entries in slot list</title>
<updated>2016-09-30T10:48:55+00:00</updated>
<author>
<name>Juergen Gross</name>
<email>jgross@suse.com</email>
</author>
<published>2016-09-22T08:45:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9f8bee9c981f5fe7382a0615d117cc128dd22458'/>
<id>9f8bee9c981f5fe7382a0615d117cc128dd22458</id>
<content type='text'>
The Xen pciback driver has a list of all pci devices it is ready to
seize. There is no check whether a to be added entry already exists.
While this might be no problem in the common case it might confuse
those which consume the list via sysfs.

Modify the handling of this list by not adding an entry which already
exists. As this will be needed later split out the list handling into
a separate function.

Signed-off-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: David Vrabel &lt;david.vrabel@citrix.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The Xen pciback driver has a list of all pci devices it is ready to
seize. There is no check whether a to be added entry already exists.
While this might be no problem in the common case it might confuse
those which consume the list via sysfs.

Modify the handling of this list by not adding an entry which already
exists. As this will be needed later split out the list handling into
a separate function.

Signed-off-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: David Vrabel &lt;david.vrabel@citrix.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>xen/pciback: simplify pcistub device handling</title>
<updated>2016-09-30T10:48:33+00:00</updated>
<author>
<name>Juergen Gross</name>
<email>jgross@suse.com</email>
</author>
<published>2016-09-22T08:45:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=1af916b701db1a9905e559e742f45818eb233d12'/>
<id>1af916b701db1a9905e559e742f45818eb233d12</id>
<content type='text'>
The Xen pciback driver maintains a list of all its seized devices.
There are two functions searching the list for a specific device with
basically the same semantics just returning different structures in
case of a match.

Split out the search function.

Signed-off-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: David Vrabel &lt;david.vrabel@citrix.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The Xen pciback driver maintains a list of all its seized devices.
There are two functions searching the list for a specific device with
basically the same semantics just returning different structures in
case of a match.

Split out the search function.

Signed-off-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: David Vrabel &lt;david.vrabel@citrix.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>xen: Remove event channel notification through Xen PCI platform device</title>
<updated>2016-09-30T10:44:34+00:00</updated>
<author>
<name>KarimAllah Ahmed</name>
<email>karahmed@amazon.de</email>
</author>
<published>2016-08-26T21:55:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=72a9b186292d98494f222226cfd24a1621796209'/>
<id>72a9b186292d98494f222226cfd24a1621796209</id>
<content type='text'>
Ever since commit 254d1a3f02eb ("xen/pv-on-hvm kexec: shutdown watches
from old kernel") using the INTx interrupt from Xen PCI platform
device for event channel notification would just lockup the guest
during bootup.  postcore_initcall now calls xs_reset_watches which
will eventually try to read a value from XenStore and will get stuck
on read_reply at XenBus forever since the platform driver is not
probed yet and its INTx interrupt handler is not registered yet. That
means that the guest can not be notified at this moment of any pending
event channels and none of the per-event handlers will ever be invoked
(including the XenStore one) and the reply will never be picked up by
the kernel.

The exact stack where things get stuck during xenbus_init:

-xenbus_init
 -xs_init
  -xs_reset_watches
   -xenbus_scanf
    -xenbus_read
     -xs_single
      -xs_single
       -xs_talkv

Vector callbacks have always been the favourite event notification
mechanism since their introduction in commit 38e20b07efd5 ("x86/xen:
event channels delivery on HVM.") and the vector callback feature has
always been advertised for quite some time by Xen that's why INTx was
broken for several years now without impacting anyone.

Luckily this also means that event channel notification through INTx
is basically dead-code which can be safely removed without impacting
anybody since it has been effectively disabled for more than 4 years
with nobody complaining about it (at least as far as I'm aware of).

This commit removes event channel notification through Xen PCI
platform device.

Cc: Boris Ostrovsky &lt;boris.ostrovsky@oracle.com&gt;
Cc: David Vrabel &lt;david.vrabel@citrix.com&gt;
Cc: Juergen Gross &lt;jgross@suse.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: x86@kernel.org
Cc: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
Cc: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Cc: Stefano Stabellini &lt;stefano.stabellini@eu.citrix.com&gt;
Cc: Julien Grall &lt;julien.grall@citrix.com&gt;
Cc: Vitaly Kuznetsov &lt;vkuznets@redhat.com&gt;
Cc: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
Cc: Ross Lagerwall &lt;ross.lagerwall@citrix.com&gt;
Cc: xen-devel@lists.xenproject.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: Anthony Liguori &lt;aliguori@amazon.com&gt;
Signed-off-by: KarimAllah Ahmed &lt;karahmed@amazon.de&gt;
Reviewed-by: Boris Ostrovsky &lt;boris.ostrovsky@oracle.com&gt;
Signed-off-by: David Vrabel &lt;david.vrabel@citrix.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Ever since commit 254d1a3f02eb ("xen/pv-on-hvm kexec: shutdown watches
from old kernel") using the INTx interrupt from Xen PCI platform
device for event channel notification would just lockup the guest
during bootup.  postcore_initcall now calls xs_reset_watches which
will eventually try to read a value from XenStore and will get stuck
on read_reply at XenBus forever since the platform driver is not
probed yet and its INTx interrupt handler is not registered yet. That
means that the guest can not be notified at this moment of any pending
event channels and none of the per-event handlers will ever be invoked
(including the XenStore one) and the reply will never be picked up by
the kernel.

The exact stack where things get stuck during xenbus_init:

-xenbus_init
 -xs_init
  -xs_reset_watches
   -xenbus_scanf
    -xenbus_read
     -xs_single
      -xs_single
       -xs_talkv

Vector callbacks have always been the favourite event notification
mechanism since their introduction in commit 38e20b07efd5 ("x86/xen:
event channels delivery on HVM.") and the vector callback feature has
always been advertised for quite some time by Xen that's why INTx was
broken for several years now without impacting anyone.

Luckily this also means that event channel notification through INTx
is basically dead-code which can be safely removed without impacting
anybody since it has been effectively disabled for more than 4 years
with nobody complaining about it (at least as far as I'm aware of).

This commit removes event channel notification through Xen PCI
platform device.

Cc: Boris Ostrovsky &lt;boris.ostrovsky@oracle.com&gt;
Cc: David Vrabel &lt;david.vrabel@citrix.com&gt;
Cc: Juergen Gross &lt;jgross@suse.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: x86@kernel.org
Cc: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
Cc: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Cc: Stefano Stabellini &lt;stefano.stabellini@eu.citrix.com&gt;
Cc: Julien Grall &lt;julien.grall@citrix.com&gt;
Cc: Vitaly Kuznetsov &lt;vkuznets@redhat.com&gt;
Cc: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
Cc: Ross Lagerwall &lt;ross.lagerwall@citrix.com&gt;
Cc: xen-devel@lists.xenproject.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: Anthony Liguori &lt;aliguori@amazon.com&gt;
Signed-off-by: KarimAllah Ahmed &lt;karahmed@amazon.de&gt;
Reviewed-by: Boris Ostrovsky &lt;boris.ostrovsky@oracle.com&gt;
Signed-off-by: David Vrabel &lt;david.vrabel@citrix.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>xen/events: Convert to hotplug state machine</title>
<updated>2016-09-30T10:23:04+00:00</updated>
<author>
<name>Sebastian Andrzej Siewior</name>
<email>bigeasy@linutronix.de</email>
</author>
<published>2016-09-07T17:19:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c8761e2016aa51a2829563b02a0a55913bdb0be8'/>
<id>c8761e2016aa51a2829563b02a0a55913bdb0be8</id>
<content type='text'>
Install the callbacks via the state machine.

Signed-off-by: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Signed-off-by: Boris Ostrovsky &lt;boris.ostrovsky@oracle.com&gt;
Signed-off-by: David Vrabel &lt;david.vrabel@citrix.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Install the callbacks via the state machine.

Signed-off-by: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Signed-off-by: Boris Ostrovsky &lt;boris.ostrovsky@oracle.com&gt;
Signed-off-by: David Vrabel &lt;david.vrabel@citrix.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>xen: rename xen_pmu_init() in sys-hypervisor.c</title>
<updated>2016-08-24T17:45:25+00:00</updated>
<author>
<name>Juergen Gross</name>
<email>jgross@suse.com</email>
</author>
<published>2016-08-02T06:53:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=5b00b504b13b2f0d1aa73d59cf8984726f19100f'/>
<id>5b00b504b13b2f0d1aa73d59cf8984726f19100f</id>
<content type='text'>
There are two functions with name xen_pmu_init() in the kernel. Rename
the one in drivers/xen/sys-hypervisor.c to avoid shadowing the one in
arch/x86/xen/pmu.c

To avoid the same problem in future rename some more functions.

Signed-off-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: David Vrabel &lt;david.vrabel@citrix.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There are two functions with name xen_pmu_init() in the kernel. Rename
the one in drivers/xen/sys-hypervisor.c to avoid shadowing the one in
arch/x86/xen/pmu.c

To avoid the same problem in future rename some more functions.

Signed-off-by: Juergen Gross &lt;jgross@suse.com&gt;
Signed-off-by: David Vrabel &lt;david.vrabel@citrix.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>xenbus: don't look up transaction IDs for ordinary writes</title>
<updated>2016-08-24T17:16:18+00:00</updated>
<author>
<name>Jan Beulich</name>
<email>JBeulich@suse.com</email>
</author>
<published>2016-08-15T15:02:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9a035a40f7f3f6708b79224b86c5777a3334f7ea'/>
<id>9a035a40f7f3f6708b79224b86c5777a3334f7ea</id>
<content type='text'>
This should really only be done for XS_TRANSACTION_END messages, or
else at least some of the xenstore-* tools don't work anymore.

Fixes: 0beef634b8 ("xenbus: don't BUG() on user mode induced condition")
Reported-by: Richard Schütz &lt;rschuetz@uni-koblenz.de&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Jan Beulich &lt;jbeulich@suse.com&gt;
Tested-by: Richard Schütz &lt;rschuetz@uni-koblenz.de&gt;
Signed-off-by: David Vrabel &lt;david.vrabel@citrix.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This should really only be done for XS_TRANSACTION_END messages, or
else at least some of the xenstore-* tools don't work anymore.

Fixes: 0beef634b8 ("xenbus: don't BUG() on user mode induced condition")
Reported-by: Richard Schütz &lt;rschuetz@uni-koblenz.de&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Jan Beulich &lt;jbeulich@suse.com&gt;
Tested-by: Richard Schütz &lt;rschuetz@uni-koblenz.de&gt;
Signed-off-by: David Vrabel &lt;david.vrabel@citrix.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>dma-mapping: use unsigned long for dma_attrs</title>
<updated>2016-08-04T12:50:07+00:00</updated>
<author>
<name>Krzysztof Kozlowski</name>
<email>k.kozlowski@samsung.com</email>
</author>
<published>2016-08-03T20:46:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=00085f1efa387a8ce100e3734920f7639c80caa3'/>
<id>00085f1efa387a8ce100e3734920f7639c80caa3</id>
<content type='text'>
The dma-mapping core and the implementations do not change the DMA
attributes passed by pointer.  Thus the pointer can point to const data.
However the attributes do not have to be a bitfield.  Instead unsigned
long will do fine:

1. This is just simpler.  Both in terms of reading the code and setting
   attributes.  Instead of initializing local attributes on the stack
   and passing pointer to it to dma_set_attr(), just set the bits.

2. It brings safeness and checking for const correctness because the
   attributes are passed by value.

Semantic patches for this change (at least most of them):

    virtual patch
    virtual context

    @r@
    identifier f, attrs;

    @@
    f(...,
    - struct dma_attrs *attrs
    + unsigned long attrs
    , ...)
    {
    ...
    }

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
     )

and

    // Options: --all-includes
    virtual patch
    virtual context

    @r@
    identifier f, attrs;
    type t;

    @@
    t f(..., struct dma_attrs *attrs);

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
     )

Link: http://lkml.kernel.org/r/1468399300-5399-2-git-send-email-k.kozlowski@samsung.com
Signed-off-by: Krzysztof Kozlowski &lt;k.kozlowski@samsung.com&gt;
Acked-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Acked-by: Robin Murphy &lt;robin.murphy@arm.com&gt;
Acked-by: Hans-Christian Noren Egtvedt &lt;egtvedt@samfundet.no&gt;
Acked-by: Mark Salter &lt;msalter@redhat.com&gt; [c6x]
Acked-by: Jesper Nilsson &lt;jesper.nilsson@axis.com&gt; [cris]
Acked-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt; [drm]
Reviewed-by: Bart Van Assche &lt;bart.vanassche@sandisk.com&gt;
Acked-by: Joerg Roedel &lt;jroedel@suse.de&gt; [iommu]
Acked-by: Fabien Dessenne &lt;fabien.dessenne@st.com&gt; [bdisp]
Reviewed-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt; [vb2-core]
Acked-by: David Vrabel &lt;david.vrabel@citrix.com&gt; [xen]
Acked-by: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt; [xen swiotlb]
Acked-by: Joerg Roedel &lt;jroedel@suse.de&gt; [iommu]
Acked-by: Richard Kuo &lt;rkuo@codeaurora.org&gt; [hexagon]
Acked-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt; [m68k]
Acked-by: Gerald Schaefer &lt;gerald.schaefer@de.ibm.com&gt; [s390]
Acked-by: Bjorn Andersson &lt;bjorn.andersson@linaro.org&gt;
Acked-by: Hans-Christian Noren Egtvedt &lt;egtvedt@samfundet.no&gt; [avr32]
Acked-by: Vineet Gupta &lt;vgupta@synopsys.com&gt; [arc]
Acked-by: Robin Murphy &lt;robin.murphy@arm.com&gt; [arm64 and dma-iommu]
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The dma-mapping core and the implementations do not change the DMA
attributes passed by pointer.  Thus the pointer can point to const data.
However the attributes do not have to be a bitfield.  Instead unsigned
long will do fine:

1. This is just simpler.  Both in terms of reading the code and setting
   attributes.  Instead of initializing local attributes on the stack
   and passing pointer to it to dma_set_attr(), just set the bits.

2. It brings safeness and checking for const correctness because the
   attributes are passed by value.

Semantic patches for this change (at least most of them):

    virtual patch
    virtual context

    @r@
    identifier f, attrs;

    @@
    f(...,
    - struct dma_attrs *attrs
    + unsigned long attrs
    , ...)
    {
    ...
    }

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
     )

and

    // Options: --all-includes
    virtual patch
    virtual context

    @r@
    identifier f, attrs;
    type t;

    @@
    t f(..., struct dma_attrs *attrs);

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
     )

Link: http://lkml.kernel.org/r/1468399300-5399-2-git-send-email-k.kozlowski@samsung.com
Signed-off-by: Krzysztof Kozlowski &lt;k.kozlowski@samsung.com&gt;
Acked-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Acked-by: Robin Murphy &lt;robin.murphy@arm.com&gt;
Acked-by: Hans-Christian Noren Egtvedt &lt;egtvedt@samfundet.no&gt;
Acked-by: Mark Salter &lt;msalter@redhat.com&gt; [c6x]
Acked-by: Jesper Nilsson &lt;jesper.nilsson@axis.com&gt; [cris]
Acked-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt; [drm]
Reviewed-by: Bart Van Assche &lt;bart.vanassche@sandisk.com&gt;
Acked-by: Joerg Roedel &lt;jroedel@suse.de&gt; [iommu]
Acked-by: Fabien Dessenne &lt;fabien.dessenne@st.com&gt; [bdisp]
Reviewed-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt; [vb2-core]
Acked-by: David Vrabel &lt;david.vrabel@citrix.com&gt; [xen]
Acked-by: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt; [xen swiotlb]
Acked-by: Joerg Roedel &lt;jroedel@suse.de&gt; [iommu]
Acked-by: Richard Kuo &lt;rkuo@codeaurora.org&gt; [hexagon]
Acked-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt; [m68k]
Acked-by: Gerald Schaefer &lt;gerald.schaefer@de.ibm.com&gt; [s390]
Acked-by: Bjorn Andersson &lt;bjorn.andersson@linaro.org&gt;
Acked-by: Hans-Christian Noren Egtvedt &lt;egtvedt@samfundet.no&gt; [avr32]
Acked-by: Vineet Gupta &lt;vgupta@synopsys.com&gt; [arc]
Acked-by: Robin Murphy &lt;robin.murphy@arm.com&gt; [arm64 and dma-iommu]
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'for-linus-4.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip</title>
<updated>2016-07-27T18:35:37+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-07-27T18:35:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=08fd8c17686c6b09fa410a26d516548dd80ff147'/>
<id>08fd8c17686c6b09fa410a26d516548dd80ff147</id>
<content type='text'>
Pull xen updates from David Vrabel:
 "Features and fixes for 4.8-rc0:

   - ACPI support for guests on ARM platforms.
   - Generic steal time support for arm and x86.
   - Support cases where kernel cpu is not Xen VCPU number (e.g., if
     in-guest kexec is used).
   - Use the system workqueue instead of a custom workqueue in various
     places"

* tag 'for-linus-4.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (47 commits)
  xen: add static initialization of steal_clock op to xen_time_ops
  xen/pvhvm: run xen_vcpu_setup() for the boot CPU
  xen/evtchn: use xen_vcpu_id mapping
  xen/events: fifo: use xen_vcpu_id mapping
  xen/events: use xen_vcpu_id mapping in events_base
  x86/xen: use xen_vcpu_id mapping when pointing vcpu_info to shared_info
  x86/xen: use xen_vcpu_id mapping for HYPERVISOR_vcpu_op
  xen: introduce xen_vcpu_id mapping
  x86/acpi: store ACPI ids from MADT for future usage
  x86/xen: update cpuid.h from Xen-4.7
  xen/evtchn: add IOCTL_EVTCHN_RESTRICT
  xen-blkback: really don't leak mode property
  xen-blkback: constify instance of "struct attribute_group"
  xen-blkfront: prefer xenbus_scanf() over xenbus_gather()
  xen-blkback: prefer xenbus_scanf() over xenbus_gather()
  xen: support runqueue steal time on xen
  arm/xen: add support for vm_assist hypercall
  xen: update xen headers
  xen-pciback: drop superfluous variables
  xen-pciback: short-circuit read path used for merging write values
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull xen updates from David Vrabel:
 "Features and fixes for 4.8-rc0:

   - ACPI support for guests on ARM platforms.
   - Generic steal time support for arm and x86.
   - Support cases where kernel cpu is not Xen VCPU number (e.g., if
     in-guest kexec is used).
   - Use the system workqueue instead of a custom workqueue in various
     places"

* tag 'for-linus-4.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (47 commits)
  xen: add static initialization of steal_clock op to xen_time_ops
  xen/pvhvm: run xen_vcpu_setup() for the boot CPU
  xen/evtchn: use xen_vcpu_id mapping
  xen/events: fifo: use xen_vcpu_id mapping
  xen/events: use xen_vcpu_id mapping in events_base
  x86/xen: use xen_vcpu_id mapping when pointing vcpu_info to shared_info
  x86/xen: use xen_vcpu_id mapping for HYPERVISOR_vcpu_op
  xen: introduce xen_vcpu_id mapping
  x86/acpi: store ACPI ids from MADT for future usage
  x86/xen: update cpuid.h from Xen-4.7
  xen/evtchn: add IOCTL_EVTCHN_RESTRICT
  xen-blkback: really don't leak mode property
  xen-blkback: constify instance of "struct attribute_group"
  xen-blkfront: prefer xenbus_scanf() over xenbus_gather()
  xen-blkback: prefer xenbus_scanf() over xenbus_gather()
  xen: support runqueue steal time on xen
  arm/xen: add support for vm_assist hypercall
  xen: update xen headers
  xen-pciback: drop superfluous variables
  xen-pciback: short-circuit read path used for merging write values
  ...
</pre>
</div>
</content>
</entry>
</feed>
