Commit Graph

57 Commits

Author SHA1 Message Date
Oleksandr Andrushchenko a67efff288 xen-pciback: allow compiling on other archs than x86
Xen-pciback driver was designed to be built for x86 only. But it
can also be used by other architectures, e.g. Arm.

Currently PCI backend implements multiple functionalities at a time,
such as:
1. It is used as a database for assignable PCI devices, e.g. xl
   pci-assignable-{add|remove|list} manipulates that list. So, whenever
   the toolstack needs to know which PCI devices can be passed through
   it reads that from the relevant sysfs entries of the pciback.
2. It is used to hold the unbound PCI devices list, e.g. when passing
   through a PCI device it needs to be unbound from the relevant device
   driver and bound to pciback (strictly speaking it is not required
   that the device is bound to pciback, but pciback is again used as a
   database of the passed through PCI devices, so we can re-bind the
   devices back to their original drivers when guest domain shuts down)
3. Device reset for the devices being passed through
4. Para-virtualised use-cases support

The para-virtualised part of the driver is not always needed as some
architectures, e.g. Arm or x86 PVH Dom0, are not using backend-frontend
model for PCI device passthrough.

For such use-cases make the very first step in splitting the
xen-pciback driver into two parts: Xen PCI stub and PCI PV backend
drivers.

For that add new configuration options CONFIG_XEN_PCI_STUB and
CONFIG_XEN_PCIDEV_STUB, so the driver can be limited in its
functionality, e.g. no support for para-virtualised scenario.
x86 platform will continue using CONFIG_XEN_PCIDEV_BACKEND for the
fully featured backend driver.

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: Anastasiia Lukianenko <anastasiia_lukianenko@epam.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20211028143620.144936-1-andr2000@gmail.com
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-11-02 08:03:43 -05:00
Muhammad Usama Anjum 28738fab6a xen/pciback: Fix incorrect type warnings
Correct enum pci_channel_io_normal should be used instead of putting
integer value 1.

Fix following smatch warnings:
drivers/xen/xen-pciback/pci_stub.c:805:40: warning: incorrect type in argument 2 (different base types)
drivers/xen/xen-pciback/pci_stub.c:805:40:    expected restricted pci_channel_state_t [usertype] state
drivers/xen/xen-pciback/pci_stub.c:805:40:    got int
drivers/xen/xen-pciback/pci_stub.c:862:40: warning: incorrect type in argument 2 (different base types)
drivers/xen/xen-pciback/pci_stub.c:862:40:    expected restricted pci_channel_state_t [usertype] state
drivers/xen/xen-pciback/pci_stub.c:862:40:    got int
drivers/xen/xen-pciback/pci_stub.c:973:31: warning: incorrect type in argument 2 (different base types)
drivers/xen/xen-pciback/pci_stub.c:973:31:    expected restricted pci_channel_state_t [usertype] state
drivers/xen/xen-pciback/pci_stub.c:973:31:    got int

Signed-off-by: Muhammad Usama Anjum <musamaanjum@gmail.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20210326181442.GA1735905@LEGION
Signed-off-by: Juergen Gross <jgross@suse.com>
2021-04-23 09:27:12 +02:00
Juergen Gross c2711441bc xen/pciback: use lateeoi irq binding
In order to reduce the chance for the system becoming unresponsive due
to event storms triggered by a misbehaving pcifront use the lateeoi irq
binding for pciback and unmask the event channel only just before
leaving the event handling function.

Restructure the handling to support that scheme. Basically an event can
come in for two reasons: either a normal request for a pciback action,
which is handled in a worker, or in case the guest has finished an AER
request which was requested by pciback.

When an AER request is issued to the guest and a normal pciback action
is currently active issue an EOI early in order to be able to receive
another event when the AER request has been finished by the guest.

Let the worker processing the normal requests run until no further
request is pending, instead of starting a new worker ion that case.
Issue the EOI only just before leaving the worker.

This scheme allows to drop calling the generic function
xen_pcibk_test_and_schedule_op() after processing of any request as
the handling of both request types is now separated more cleanly.

This is part of XSA-332.

Cc: stable@vger.kernel.org
Reported-by: Julien Grall <julien@xen.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wl@xen.org>
2020-10-20 10:22:08 +02:00
Bjorn Helgaas 6904945420 xen-pciback: Use dev_printk() when possible
Use dev_printk() when possible to include device and driver information in
the conventional format.

Add "#define dev_fmt" when needed to preserve DRV_NAME or KBUILD_MODNAME in
messages.

No functional change intended.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20200527174326.254329-2-helgaas@kernel.org
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-05-27 17:27:37 -05:00
Marek Marczykowski-Górecki 476878e4b2 xen-pciback: optionally allow interrupt enable flag writes
QEMU running in a stubdom needs to be able to set INTX_DISABLE, and the
MSI(-X) enable flags in the PCI config space. This adds an attribute
'allow_interrupt_control' which when set for a PCI device allows writes
to this flag(s). The toolstack will need to set this for stubdoms.
When enabled, guest (stubdomain) will be allowed to set relevant enable
flags, but only one at a time - i.e. it refuses to enable more than one
of INTx, MSI, MSI-X at a time.

This functionality is needed only for config space access done by device
model (stubdomain) serving a HVM with the actual PCI device. It is not
necessary and unsafe to enable direct access to those bits for PV domain
with the device attached. For PV domains, there are separate protocol
messages (XEN_PCI_OP_{enable,disable}_{msi,msix}) for this purpose.
Those ops in addition to setting enable bits, also configure MSI(-X) in
dom0 kernel - which is undesirable for PCI passthrough to HVM guests.

This should not introduce any new security issues since a malicious
guest (or stubdom) can already generate MSIs through other ways, see
[1] page 8. Additionally, when qemu runs in dom0, it already have direct
access to those bits.

This is the second iteration of this feature. First was proposed as a
direct Xen interface through a new hypercall, but ultimately it was
rejected by the maintainer, because of mixing pciback and hypercalls for
PCI config space access isn't a good design. Full discussion at [2].

[1]: https://invisiblethingslab.com/resources/2011/Software%20Attacks%20on%20Intel%20VT-d.pdf
[2]: https://xen.markmail.org/thread/smpgpws4umdzizze

[part of the commit message and sysfs handling]
Signed-off-by: Simon Gaiser <simon@invisiblethingslab.com>
[the rest]
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
[boris: A few small changes suggested by Roger, some formatting changes]
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-01-15 16:50:13 -06:00
Ross Lagerwall 1669907e3d xen/pciback: Check dev_data before using it
If pcistub_init_device fails, the release function will be called with
dev_data set to NULL.  Check it before using it to avoid a NULL pointer
dereference.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2018-12-17 10:29:50 -05:00
Jia-Ju Bai de3d01fd85 xen: xen-pciback: Replace GFP_ATOMIC with GFP_KERNEL in pcistub_reg_add
pcistub_reg_add() is never called in atomic context.

pcistub_reg_add() is only called by pcistub_quirk_add, which is
only set in DRIVER_ATTR().

Despite never getting called from atomic context,
pcistub_reg_add() calls kzalloc() with GFP_ATOMIC,
which does not sleep for allocation.
GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL,
which can sleep and improve the possibility of sucessful allocation.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2018-04-16 10:20:45 -04:00
Jia-Ju Bai 9eb5f15b47 xen: xen-pciback: Replace GFP_ATOMIC with GFP_KERNEL in pcistub_device_alloc
pcistub_device_alloc() is never called in atomic context.

The call chain ending up at pcistub_device_alloc() is:
[1] pcistub_device_alloc() <- pcistub_seize() <- pcistub_probe()
pcistub_probe() is only set as ".probe" in struct pci_driver.
This function is not called in atomic context.

Despite never getting called from atomic context,
pcistub_device_alloc() calls kzalloc() with GFP_ATOMIC,
which does not sleep for allocation.
GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL,
which can sleep and improve the possibility of sucessful allocation.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2018-04-16 10:20:21 -04:00
Jia-Ju Bai bb52e3169c xen: xen-pciback: Replace GFP_ATOMIC with GFP_KERNEL in pcistub_init_device
pcistub_init_device() is never called in atomic context.

The call chain ending up at pcistub_init_device() is:
[1] pcistub_init_device() <- pcistub_seize() <- pcistub_probe()
[2] pcistub_init_device() <- pcistub_init_devices_late() <-
	xen_pcibk_init()
pcistub_probe() is only set as ".probe" in struct pci_driver.
xen_pcibk_init() is is only set as a parameter of module_init().
These functions are not called in atomic context.

Despite never getting called from atomic context,
pcistub_init_device() calls kzalloc() with GFP_ATOMIC,
which does not sleep for allocation.
GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL,
which can sleep and improve the possibility of sucessful allocation.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2018-04-16 10:20:12 -04:00
Jia-Ju Bai cc5cd50796 xen: xen-pciback: Replace GFP_ATOMIC with GFP_KERNEL in pcistub_probe
pcistub_probe() is never called in atomic context.
This function is only set as ".probe" in struct pci_driver.

Despite never getting called from atomic context,
pcistub_probe() calls kmalloc() with GFP_ATOMIC,
which does not sleep for allocation.
GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL,
which can sleep and improve the possibility of sucessful allocation.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2018-04-16 10:19:52 -04:00
Greg Kroah-Hartman 0538dcb017 xen: xen-pciback: remove DRIVER_ATTR() usage
It's better to be explicit and use the DRIVER_ATTR_RW() and
DRIVER_ATTR_RO() macros when defining a driver's sysfs file.

Bonus is this fixes up a checkpatch.pl warning.

This is part of a series to drop DRIVER_ATTR() from the tree entirely.

Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28 16:42:30 +02:00
Juergen Gross b057878b2a xen/pciback: support driver_override
Support the driver_override scheme introduced with commit 782a985d7a
("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 > /sys/bus/pci/devices/0000\:07\:10.0/driver/unbind
echo 0000:07:10.0 > /sys/bus/pci/drivers/pciback/new_slot
echo 0000:07:10.0 > /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 > /sys/bus/pci/devices/0000\:07\:10.0/driver_override
echo 0000:07:10.0 > /sys/bus/pci/devices/0000\:07\:10.0/driver/unbind
echo 0000:07:10.0 > /sys/bus/pci/drivers_probe

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

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-09-30 11:49:02 +01:00
Juergen Gross 9f8bee9c98 xen/pciback: avoid multiple entries in slot list
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 <jgross@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-09-30 11:48:55 +01:00
Juergen Gross 1af916b701 xen/pciback: simplify pcistub device handling
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 <jgross@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-09-30 11:48:33 +01:00
Konrad Rzeszutek Wilk 74beaf6270 xen/pciback: Don't print scary messages when unsupported by hypervisor.
We print at the warninig level messages such as:
pciback 0000:90:00.5: MSI-X preparation failed (-38)

which is due to the hypervisor not supporting this sub-hypercall
(which was added in Xen 4.3).

Instead of having scary messages all the time - only have it
when the hypercall is actually supported.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-03-16 14:49:14 +00:00
Jan Beulich 6945c59c77 xen-pciback: drop SR-IOV VFs when PF driver unloads
When a PF driver unloads, it may find it necessary to leave the VFs
around simply because of pciback having marked them as assigned to a
guest. Utilize a suitable notification to let go of the VFs, thus
allowing the PF to go back into the state it was before its driver
loaded (which in particular allows the driver to be loaded again with
it being able to create the VFs anew, but which also allows to then
pass through the PF instead of the VFs).

Don't do this however for any VFs currently in active use by a guest.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
[v2: Removed the switch statement, moved it about]
[v3: Redid it a bit differently]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-12-04 12:42:03 +00:00
Konrad Rzeszutek Wilk b1df4a56bf xen/pciback: Restore configuration space when detaching from a guest.
The commit "xen/pciback: Don't deadlock when unbinding." was using
the version of pci_reset_function which would lock the device lock.
That is no good as we can dead-lock. As such we swapped to using
the lock-less version and requiring that the callers
of 'pcistub_put_pci_dev' take the device lock. And as such
this bug got exposed.

Using the lock-less version is  OK, except that we tried to
use 'pci_restore_state' after the lock-less version of
__pci_reset_function_locked - which won't work as 'state_saved'
is set to false. Said 'state_saved' is a toggle boolean that
is to be used by the sequence of a) pci_save_state/pci_restore_state
or b) pci_load_and_free_saved_state/pci_restore_state. We don't
want to use a) as the guest might have messed up the PCI
configuration space and we want it to revert to the state
when the PCI device was binded to us. Therefore we pick
b) to restore the configuration space.

We restore from our 'golden' version of PCI configuration space, when an:
 - Device is unbinded from pciback
 - Device is detached from a guest.

Reported-by:  Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-12-04 12:42:02 +00:00
Konrad Rzeszutek Wilk c1a04339e5 xen/pciback: Remove tons of dereferences
A little cleanup. No functional difference.

Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-12-04 12:42:01 +00:00
Konrad Rzeszutek Wilk b5d512147a xen/pciback: Include the domain id if removing the device whilst still in use
Cleanup the function a bit - also include the id of the
domain that is using the device.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-12-04 12:41:59 +00:00
Konrad Rzeszutek Wilk ac8010221d driver core: Provide an wrapper around the mutex to do lockdep warnings
Instead of open-coding it in drivers that want to double check
that their functions are indeed holding the device lock.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Suggested-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-12-04 12:41:59 +00:00
Konrad Rzeszutek Wilk e8801a7418 xen/pciback: Don't deadlock when unbinding.
As commit 0a9fd01529
'xen/pciback: Document the entry points for 'pcistub_put_pci_dev''
explained there are four entry points in this function.
Two of them are when the user fiddles in the SysFS to
unbind a device which might be in use by a guest or not.

Both 'unbind' states will cause a deadlock as the the PCI lock has
already been taken, which then pci_device_reset tries to take.

We can simplify this by requiring that all callers of
pcistub_put_pci_dev MUST hold the device lock. And then
we can just call the lockless version of pci_device_reset.

To make it even simpler we will modify xen_pcibk_release_pci_dev
to quality whether it should take a lock or not - as it ends
up calling xen_pcibk_release_pci_dev and needs to hold the lock.

Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-12-04 12:41:58 +00:00
Ethan Zhao be507fd090 xen/pciback: Use PCI device flag helper functions
Use PCI device flag helper functions when assigning or releasing device.
No functional change.

Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>
2014-09-16 16:19:17 -06:00
Benoit Taine 9baa3c34ac PCI: Remove DEFINE_PCI_DEVICE_TABLE macro use
We should prefer `struct pci_device_id` over `DEFINE_PCI_DEVICE_TABLE` to
meet kernel coding style guidelines.  This issue was reported by checkpatch.

A simplified version of the semantic patch that makes this change is as
follows (http://coccinelle.lip6.fr/):

// <smpl>

@@
identifier i;
declarer name DEFINE_PCI_DEVICE_TABLE;
initializer z;
@@

- DEFINE_PCI_DEVICE_TABLE(i)
+ const struct pci_device_id i[]
= z;

// </smpl>

[bhelgaas: add semantic patch]
Signed-off-by: Benoit Taine <benoit.taine@lip6.fr>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-08-12 12:15:14 -06:00
Konrad Rzeszutek Wilk 0a9fd01529 xen/pciback: Document the entry points for 'pcistub_put_pci_dev'
which are quite a few. It should be evident that dealing with that
many options is a bit complex.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-05-23 12:33:55 -04:00
Konrad Rzeszutek Wilk 24d8bf1b0a xen/pciback: Document when the 'unbind' and 'bind' functions are called.
And also mention that you cannot do any pci_reset_function,
pci_reset_slot, or such calls. This is because they take the same
lock as SysFS does - and we would end up with a dead-lock if
we call those functions.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-05-23 12:33:50 -04:00
Konrad Rzeszutek Wilk 8be9df6d4b xen-pciback: Document when we FLR an PCI device.
When the toolstack wants us to drop or add an PCI device it
changes the XenBus state to Configuring - and as result of that
we find out which devices we should still be exporting out and
which ones not. For the ones we don't need anymore we need to
do an PCI reset so that it is ready for the next guest.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-05-23 12:33:43 -04:00
Konrad Rzeszutek Wilk fcb8ce968f xen-pciback: First reset, then free.
We were doing the operations of freeing and reset in the wrong
order. Granted nothing broke because the reset functions just
set bar->which = 0.

But nonethless this was incorrect.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-05-23 12:33:36 -04:00
Konrad Rzeszutek Wilk 8899035eec xen-pciback: Cleanup up pcistub_put_pci_dev
We are using 'psdev->dev','found_psdev->dev', and 'dev' at the
same time - and they all point to the same structure.

To keep it straight lets just use one - 'dev'.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-05-23 12:33:30 -04:00
Joe Perches 283c0972d5 xen: Convert printks to pr_<level>
Convert printks to pr_<level> (excludes printk(KERN_DEBUG...)
to be more consistent throughout the xen subsystem.

Add pr_fmt with KBUILD_MODNAME or "xen:" KBUILD_MODNAME
Coalesce formats and add missing word spaces
Add missing newlines
Align arguments and reflow to 80 columns
Remove DRV_NAME from formats as pr_fmt adds the same content

This does change some of the prefixes of these messages
but it also does make them more consistent.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-28 11:19:58 -04:00
Wei Yongjun 405010df1d xen-pciback: fix error return code in pcistub_irq_handler_switch()
Fix to return -ENOENT in the pcistub_device_find() and pci_get_drvdata()
error handling case instead of 0(overwrite to 0 by str_to_slot()), as done
elsewhere in this function.

Acked-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-06-10 08:43:28 -04:00
Jan Beulich d69c0e3975 xen-pciback: more uses of cached MSI-X capability offset
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-05-29 09:04:22 -04:00
Jan Beulich 909b3fdb0d xen-pciback: notify hypervisor about devices intended to be assigned to guests
For MSI-X capable devices the hypervisor wants to write protect the
MSI-X table and PBA, yet it can't assume that resources have been
assigned to their final values at device enumeration time. Thus have
pciback do that notification, as having the device controlled by it is
a prerequisite to assigning the device to guests anyway.

This is the kernel part of hypervisor side commit 4245d33 ("x86/MSI:
add mechanism to fully protect MSI-X table from PV guest accesses") on
the master branch of git://xenbits.xen.org/xen.git.

CC: stable@vger.kernel.org
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-03-22 10:20:55 -04:00
Greg Kroah-Hartman 345a52558e Drivers: xen: remove __dev* attributes.
CONFIG_HOTPLUG is going away as an option.  As a result, the __dev*
markings need to be removed.

This change removes the use of __devinit, and __devinitdata from these
drivers.

Based on patches originally written by Bill Pemberton, but redone by me
in order to handle some of the coding style issues better, by hand.

Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-03 15:57:01 -08:00
Linus Torvalds 896ea17d3d Features:
- Add necessary infrastructure to make balloon driver work under ARM.
  - Add /dev/xen/privcmd interfaces to work with ARM and PVH.
  - Improve Xen PCIBack wild-card parsing.
  - Add Xen ACPI PAD (Processor Aggregator) support - so can offline/online
    sockets depending on the power consumption.
  - PVHVM + kexec = use an E820_RESV region for the shared region so we don't
    overwrite said region during kexec reboot.
  - Cleanups, compile fixes.
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Merge tag 'stable/for-linus-3.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull Xen updates from Konrad Rzeszutek Wilk:
 - Add necessary infrastructure to make balloon driver work under ARM.
 - Add /dev/xen/privcmd interfaces to work with ARM and PVH.
 - Improve Xen PCIBack wild-card parsing.
 - Add Xen ACPI PAD (Processor Aggregator) support - so can offline/
   online sockets depending on the power consumption.
 - PVHVM + kexec = use an E820_RESV region for the shared region so we
   don't overwrite said region during kexec reboot.
 - Cleanups, compile fixes.

Fix up some trivial conflicts due to the balloon driver now working on
ARM, and there were changes next to the previous work-arounds that are
now gone.

* tag 'stable/for-linus-3.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/PVonHVM: fix compile warning in init_hvm_pv_info
  xen: arm: implement remap interfaces needed for privcmd mappings.
  xen: correctly use xen_pfn_t in remap_domain_mfn_range.
  xen: arm: enable balloon driver
  xen: balloon: allow PVMMU interfaces to be compiled out
  xen: privcmd: support autotranslated physmap guests.
  xen: add pages parameter to xen_remap_domain_mfn_range
  xen/acpi: Move the xen_running_on_version_or_later function.
  xen/xenbus: Remove duplicate inclusion of asm/xen/hypervisor.h
  xen/acpi: Fix compile error by missing decleration for xen_domain.
  xen/acpi: revert pad config check in xen_check_mwait
  xen/acpi: ACPI PAD driver
  xen-pciback: reject out of range inputs
  xen-pciback: simplify and tighten parsing of device IDs
  xen PVonHVM: use E820_Reserved area for shared_info
2012-12-13 14:29:16 -08:00
Masanari Iida 744627e91c treewide: fix printk typo in multiple drivers
Correct spelling typo in multiple drivers.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-11-19 11:08:17 +01:00
Jan Beulich b3e40b72bb xen-pciback: reject out of range inputs
This add checks for out of range numbers (including in cases where the
folding of slot and function into a single value could yield false
matches).

It also removes the bogus field width restrictions in str_to_quirk() -
nowhere else in the driver this is being done, and hence this function
could reject input the equivalent of which would be happily accepted
in other places (in particular, "0x" prefixes causing the effective
width of the actual number to be either zero or less than what would be
required to cover the full range of valid values). Note that for the
moment this second part is cosmetic only, as the kernel's sscanf()
currently ignores the field widths, but a patch to overcome this is on
its way.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-11-02 11:04:03 -04:00
Jan Beulich 5b71fbdc64 xen-pciback: simplify and tighten parsing of device IDs
Now that at least one of the conformance problems of the kernel's
sscanf() was addressed (commit da99075c1d),
we can improve the parsing done in xen-pciback both in terms of code
readability and correctness (in particular properly rejecting input
strings not well formed).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-11-02 11:04:02 -04:00
Linus Torvalds 56d92aa5cf Features:
* When hotplugging PCI devices in a PV guest we can allocate Xen-SWIOTLB later.
  * Cleanup Xen SWIOTLB.
  * Support pages out grants from HVM domains in the backends.
  * Support wild cards in xen-pciback.hide=(BDF) arguments.
  * Update grant status updates with upstream hypervisor.
  * Boot PV guests with more than 128GB.
  * Cleanup Xen MMU code/add comments.
  * Obtain XENVERS using a preferred method.
  * Lay out generic changes to support Xen ARM.
  * Allow privcmd ioctl for HVM (used to do only PV).
  * Do v2 of mmap_batch for privcmd ioctls.
  * If hypervisor saves the LED keyboard light - we will now instruct the kernel
    about its state.
 Fixes:
  * More fixes to Xen PCI backend for various calls/FLR/etc.
  * With more than 4GB in a 64-bit PV guest disable native SWIOTLB.
  * Fix up smatch warnings.
  * Fix up various return values in privmcmd and mm.
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Merge tag 'stable/for-linus-3.7-x86-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull Xen update from Konrad Rzeszutek Wilk:
 "Features:
   - When hotplugging PCI devices in a PV guest we can allocate
     Xen-SWIOTLB later.
   - Cleanup Xen SWIOTLB.
   - Support pages out grants from HVM domains in the backends.
   - Support wild cards in xen-pciback.hide=(BDF) arguments.
   - Update grant status updates with upstream hypervisor.
   - Boot PV guests with more than 128GB.
   - Cleanup Xen MMU code/add comments.
   - Obtain XENVERS using a preferred method.
   - Lay out generic changes to support Xen ARM.
   - Allow privcmd ioctl for HVM (used to do only PV).
   - Do v2 of mmap_batch for privcmd ioctls.
   - If hypervisor saves the LED keyboard light - we will now instruct
     the kernel about its state.
  Fixes:
   - More fixes to Xen PCI backend for various calls/FLR/etc.
   - With more than 4GB in a 64-bit PV guest disable native SWIOTLB.
   - Fix up smatch warnings.
   - Fix up various return values in privmcmd and mm."

* tag 'stable/for-linus-3.7-x86-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: (48 commits)
  xen/pciback: Restore the PCI config space after an FLR.
  xen-pciback: properly clean up after calling pcistub_device_find()
  xen/vga: add the xen EFI video mode support
  xen/x86: retrieve keyboard shift status flags from hypervisor.
  xen/gndev: Xen backend support for paged out grant targets V4.
  xen-pciback: support wild cards in slot specifications
  xen/swiotlb: Fix compile warnings when using plain integer instead of NULL pointer.
  xen/swiotlb: Remove functions not needed anymore.
  xen/pcifront: Use Xen-SWIOTLB when initting if required.
  xen/swiotlb: For early initialization, return zero on success.
  xen/swiotlb: Use the swiotlb_late_init_with_tbl to init Xen-SWIOTLB late when PV PCI is used.
  xen/swiotlb: Move the error strings to its own function.
  xen/swiotlb: Move the nr_tbl determination in its own function.
  xen/arm: compile and run xenbus
  xen: resynchronise grant table status codes with upstream
  xen/privcmd: return -EFAULT on error
  xen/privcmd: Fix mmap batch ioctl error status copy back.
  xen/privcmd: add PRIVCMD_MMAPBATCH_V2 ioctl
  xen/mm: return more precise error from xen_remap_domain_range()
  xen/mmu: If the revector fails, don't attempt to revector anything else.
  ...
2012-10-02 22:09:10 -07:00
Konrad Rzeszutek Wilk c341ca45ce xen/pciback: Restore the PCI config space after an FLR.
When we do an FLR, or D0->D3_hot we may lose the BARs as the
device has turned itself off (and on). This means the device cannot
function unless the pci_restore_state is called - which it is
when the PCI device is unbound from the Xen PCI backend driver.
For PV guests it ends up calling pci_enable_device / pci_enable_msi[x]
which does the proper steps

That however is not happening if a HVM guest is run as QEMU
deals with PCI configuration space. QEMU also requires that the
device be "parked"  under the ownership of a pci-stub driver to
guarantee that the PCI device is not being used. Hence we
follow the same incantation as pci_reset_function does - by
doing an FLR, then restoring the PCI configuration space.

The result of this patch is that when you run lspci, you get
now this:

-       Region 0: [virtual] Memory at fe8c0000 (32-bit, non-prefetchable) [size=128K]
-       Region 1: [virtual] Memory at fe800000 (32-bit, non-prefetchable) [size=512K]
+       Region 0: Memory at fe8c0000 (32-bit, non-prefetchable) [size=128K]
+       Region 1: Memory at fe800000 (32-bit, non-prefetchable) [size=512K]
        Region 2: I/O ports at c000 [size=32]
-       Region 3: [virtual] Memory at fe8e0000 (32-bit, non-prefetchable) [size=16K]
+       Region 3: Memory at fe8e0000 (32-bit, non-prefetchable) [size=16K]

The [virtual] means that lspci read those entries from SysFS but when
it read them from the device it got a different value (0xfffffff).

CC: stable@vger.kernel.org #only for 3.5, 3.6
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-09-25 17:26:28 -04:00
Jan Beulich e6aa70a0d5 xen-pciback: properly clean up after calling pcistub_device_find()
As the function calls pcistub_device_get() before returning non-NULL,
its callers need to take care of calling pcistub_device_put() on
(mostly, but not exclusively) error paths.

Otoh, the function already guarantees that the 'dev' member is non-NULL
upon successful return, so callers do not need to check for this a
second time.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-09-25 08:53:27 -04:00
Jan Beulich c3cb470980 xen-pciback: support wild cards in slot specifications
Particularly for hiding sets of SR-IOV devices, specifying them all
individually is rather cumbersome. Therefore, allow function and slot
numbers to be replaced by a wildcard character ('*').

Unfortunately this gets complicated by the in-kernel sscanf()
implementation not being really standard conformant - matching of
plain text tails cannot be checked by the caller (a patch to overcome
this will be sent shortly, and a follow-up patch for simplifying the
code is planned to be sent when that fixed went upstream).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-09-18 10:44:17 -04:00
Bjorn Helgaas 78890b5989 Merge commit 'v3.6-rc5' into next
* commit 'v3.6-rc5': (1098 commits)
  Linux 3.6-rc5
  HID: tpkbd: work even if the new Lenovo Keyboard driver is not configured
  Remove user-triggerable BUG from mpol_to_str
  xen/pciback: Fix proper FLR steps.
  uml: fix compile error in deliver_alarm()
  dj: memory scribble in logi_dj
  Fix order of arguments to compat_put_time[spec|val]
  xen: Use correct masking in xen_swiotlb_alloc_coherent.
  xen: fix logical error in tlb flushing
  xen/p2m: Fix one-off error in checking the P2M tree directory.
  powerpc: Don't use __put_user() in patch_instruction
  powerpc: Make sure IPI handlers see data written by IPI senders
  powerpc: Restore correct DSCR in context switch
  powerpc: Fix DSCR inheritance in copy_thread()
  powerpc: Keep thread.dscr and thread.dscr_inherit in sync
  powerpc: Update DSCR on all CPUs when writing sysfs dscr_default
  powerpc/powernv: Always go into nap mode when CPU is offline
  powerpc: Give hypervisor decrementer interrupts their own handler
  powerpc/vphn: Fix arch_update_cpu_topology() return value
  ARM: gemini: fix the gemini build
  ...

Conflicts:
	drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
	drivers/rapidio/devices/tsi721.c
2012-09-13 08:41:01 -06:00
Stephen Hemminger 1d3520357d make drivers with pci error handlers const
Covers the rest of the uses of pci error handler.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2012-09-07 16:35:00 -06:00
Konrad Rzeszutek Wilk 80ba77dfbc xen/pciback: Fix proper FLR steps.
When we do FLR and save PCI config we did it in the wrong order.
The end result was that if a PCI device was unbind from
its driver, then binded to xen-pciback, and then back to its
driver we would get:

> lspci -s 04:00.0
04:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection
13:42:12 # 4 :~/
> echo "0000:04:00.0" > /sys/bus/pci/drivers/pciback/unbind
> modprobe e1000e
e1000e: Intel(R) PRO/1000 Network Driver - 2.0.0-k
e1000e: Copyright(c) 1999 - 2012 Intel Corporation.
e1000e 0000:04:00.0: Disabling ASPM L0s L1
e1000e 0000:04:00.0: enabling device (0000 -> 0002)
xen: registering gsi 48 triggering 0 polarity 1
Already setup the GSI :48
e1000e 0000:04:00.0: Interrupt Throttling Rate (ints/sec) set to dynamic conservative mode
e1000e: probe of 0000:04:00.0 failed with error -2

This fixes it by first saving the PCI configuration space, then
doing the FLR.

Reported-by: Ren, Yongjie <yongjie.ren@intel.com>
Reported-and-Tested-by: Tobias Geiger <tobias.geiger@vido.info>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: stable@vger.kernel.org
2012-09-06 09:22:02 -04:00
Linus Torvalds d4c6fa73fe Features:
- PV multiconsole support, so that there can be hvc1, hvc2, etc;
  - P-state and C-state power management driver that uploads said
    power management data to the hypervisor. It also inhibits cpufreq
    scaling drivers to load so that only the hypervisor can make power
    management decisions - fixing a weird perf bug.
  - Function Level Reset (FLR) support in the Xen PCI backend.
 Fixes:
  - Kconfig dependencies for Xen PV keyboard and video
  - Compile warnings and constify fixes
  - Change over to use percpu_xxx instead of this_cpu_xxx
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Merge tag 'stable/for-linus-3.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull xen updates from Konrad Rzeszutek Wilk:
 "which has three neat features:

   - PV multiconsole support, so that there can be hvc1, hvc2, etc; This
     can be used in HVM and in PV mode.

   - P-state and C-state power management driver that uploads said power
     management data to the hypervisor.  It also inhibits cpufreq
     scaling drivers to load so that only the hypervisor can make power
     management decisions - fixing a weird perf bug.

     There is one thing in the Kconfig that you won't like: "default y
     if (X86_ACPI_CPUFREQ = y || X86_POWERNOW_K8 = y)" (note, that it
     all depends on CONFIG_XEN which depends on CONFIG_PARAVIRT which by
     default is off).  I've a fix to convert that boolean expression
     into "default m" which I am going to post after the cpufreq git
     pull - as the two patches to make this work depend on a fix in Dave
     Jones's tree.

   - Function Level Reset (FLR) support in the Xen PCI backend.

  Fixes:

   - Kconfig dependencies for Xen PV keyboard and video
   - Compile warnings and constify fixes
   - Change over to use percpu_xxx instead of this_cpu_xxx"

Fix up trivial conflicts in drivers/tty/hvc/hvc_xen.c due to changes to
a removed commit.

* tag 'stable/for-linus-3.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen kconfig: relax INPUT_XEN_KBDDEV_FRONTEND deps
  xen/acpi-processor: C and P-state driver that uploads said data to hypervisor.
  xen: constify all instances of "struct attribute_group"
  xen/xenbus: ignore console/0
  hvc_xen: introduce HVC_XEN_FRONTEND
  hvc_xen: implement multiconsole support
  hvc_xen: support PV on HVM consoles
  xenbus: don't free other end details too early
  xen/enlighten: Expose MWAIT and MWAIT_LEAF if hypervisor OKs it.
  xen/setup/pm/acpi: Remove the call to boot_option_idle_override.
  xenbus: address compiler warnings
  xen: use this_cpu_xxx replace percpu_xxx funcs
  xen/pciback: Support pci_reset_function, aka FLR or D3 support.
  pci: Introduce __pci_reset_function_locked to be used when holding device_lock.
  xen: Utilize the restore_msi_irqs hook.
2012-03-22 20:16:14 -07:00
Konrad Rzeszutek Wilk e4de866a83 xen/pci[front|back]: Use %d instead of %1x for displaying PCI devfn.
.. as the rest of the kernel is using that format.

Suggested-by: Марк Коренберг <socketpair@gmail.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-02-03 16:06:57 -05:00
Konrad Rzeszutek Wilk cd9db80e52 xen/pciback: Support pci_reset_function, aka FLR or D3 support.
We use the __pci_reset_function_locked to perform the action.
Also on attaching ("bind") and detaching ("unbind") we save and
restore the configuration states. When the device is disconnected
from a guest we use the "pci_reset_function" to also reset the
device before being passed to another guest.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-12 12:00:19 -05:00
Konrad Rzeszutek Wilk 3167355801 xen/pciback: Fix "device has been assigned to X domain!" warning
The full warning is:
"pciback 0000:05:00.0: device has been assigned to 2 domain! Over-writting the ownership, but beware."

which is correct - the previous domain that was using the device
forgot to unregister the ownership. This patch fixes this by
calling the unregister ownership function when the PCI device is
relinquished from the guest domain.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-07 20:35:56 -05:00
Konrad Rzeszutek Wilk 97309d3974 xen/pciback: Move the PCI_DEV_FLAGS_ASSIGNED ops to the "[un|]bind"
operation instead of doing it per guest creation/disconnection. Without
this we could have potentially unloaded the vf driver from the
xen pciback control even if the driver was binded to the xen-pciback.
This will hold on to it until the user "unbind"s the PCI device using
SysFS.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-07 20:35:55 -05:00
Konrad Rzeszutek Wilk 4645bf3067 xen/pciback: Check if the device is found instead of blindly assuming so.
Just in case it is not found, don't try to dereference it.

[v1: Added WARN_ON, suggested by Jan Beulich <JBeulich@suse.com>]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-19 17:01:10 -04:00