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476 Commits (redonkable)

Author SHA1 Message Date
Jason Wang 87646a348e virtio_ring: allow to store zero as the ctx
Allow zero to be store as a ctx, with this we could store e.g zero
value which could be meaningful for the case of storing headroom
through ctx.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-24 13:37:00 -07:00
Michael S. Tsirkin e41b135550 virtio_balloon: disable VIOMMU support
virtio balloon bypasses the DMA API entirely so does not support the
VIOMMU right now.  It's not clear we need that support, for now let's
just make sure we don't pretend to support it.

Cc: stable@vger.kernel.org
Cc: Wei Wang <wei.w.wang@intel.com>
Fixes: 1a93769399 ("virtio: new feature to detect IOMMU device quirk")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2017-06-18 23:13:35 +03:00
Michael S. Tsirkin 5a08b04f63 virtio: allow extra context per descriptor
Allow extra context per descriptor. To avoid slow down for data path,
this disables use of indirect descriptors for this vq.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-02 23:41:43 +03:00
Michael S. Tsirkin f94682dde5 virtio: add context flag to find vqs
Allows maintaining extra context per vq.  For ease of use, passing in
NULL is legal and disables the feature for all vqs.

Includes fixes by Christian for s390, acked by Cornelia.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-02 23:41:43 +03:00
Michael S. Tsirkin 9b2bbdb227 virtio: wrap find_vqs
We are going to add more parameters to find_vqs, let's wrap the call so
we don't need to tweak all drivers every time.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-02 23:41:42 +03:00
Marc Zyngier 2f8dc3a01f virtio-pci: Remove affinity hint before freeing the interrupt
virtio-pci registers a per-vq affinity hint when using MSIX,
but fails to remove it when freeing the interrupt, resulting
in this type of splat:

[   31.111202] WARNING: CPU: 0 PID: 2823 at kernel/irq/manage.c:1503 __free_irq+0x2c4/0x2c8
[   31.114689] Modules linked in:
[   31.116101] CPU: 0 PID: 2823 Comm: kexec Not tainted 4.10.0+ #6941
[   31.118911] Hardware name: Generic DT based system
[   31.121319] [<c022fb78>] (unwind_backtrace) from [<c0229d8c>] (show_stack+0x18/0x1c)
[   31.125017] [<c0229d8c>] (show_stack) from [<c05192f4>] (dump_stack+0x84/0x98)
[   31.128427] [<c05192f4>] (dump_stack) from [<c023d940>] (__warn+0xf4/0x10c)
[   31.131910] [<c023d940>] (__warn) from [<c023da20>] (warn_slowpath_null+0x28/0x30)
[   31.135543] [<c023da20>] (warn_slowpath_null) from [<c0290238>] (__free_irq+0x2c4/0x2c8)
[   31.139355] [<c0290238>] (__free_irq) from [<c02902d0>] (free_irq+0x44/0x78)
[   31.142909] [<c02902d0>] (free_irq) from [<c059d3a8>] (vp_del_vqs+0x68/0x1c0)
[   31.146299] [<c059d3a8>] (vp_del_vqs) from [<c056ca4c>] (pci_device_shutdown+0x3c/0x78)

The obvious fix is to drop the affinity hint before freeing the
interrupt.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-11 00:30:20 +03:00
Michael S. Tsirkin 0a9b3f47da Revert "virtio_pci: remove struct virtio_pci_vq_info"
This reverts commit 5c34d002dc.

Conflicts:
	drivers/virtio/virtio_pci_common.c

The cleanup seems to be one of the changes that broke
hybernation for some users. We are still not sure why
but revert helps.

This reverts the cleanup changes but keeps the affinity support.

Tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-11 00:29:59 +03:00
Michael S. Tsirkin 0b0f9dc52e Revert "virtio_pci: use shared interrupts for virtqueues"
This reverts commit 07ec51480b.

Conflicts:
	drivers/virtio/virtio_pci_common.c

Unfortunately the idea does not work with threadirqs
as more than 32 queues can then map to a single interrupts.

Further, the cleanup seems to be one of the changes that broke
hybernation for some users. We are still not sure why
but revert helps.

This reverts the cleanup changes but keeps the affinity support.

Tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-11 00:28:57 +03:00
Michael S. Tsirkin 2008c1544c Revert "virtio_pci: don't duplicate the msix_enable flag in struct pci_dev"
This reverts commit 53a020c661.

The cleanup seems to be one of the changes that broke
hybernation for some users. We are still not sure why
but revert helps.

Tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-11 00:28:41 +03:00
Michael S. Tsirkin bf951b1045 Revert "virtio_pci: simplify MSI-X setup"
This reverts commit 52a6151612.

Conflicts:
	drivers/virtio/virtio_pci_common.c

The cleanup seems to be one of the changes that broke
hybernation for some users. We are still not sure why
but revert helps.

This reverts the cleanup changes but keeps the affinity support.

Tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-11 00:19:40 +03:00
Michael S. Tsirkin 8f10d0149f Revert "virtio_pci: fix out of bound access for msix_names"
This reverts commit de85ec8b07.

Follow-up patches will revert 07ec51480b ("virtio_pci: use shared
interrupts for virtqueues") that triggered the problem so no need for
this one anymore.

Tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-10 23:27:50 +03:00
Michael S. Tsirkin 404123c2db virtio: allow drivers to validate features
Some drivers can't support all features in all configurations.  At the
moment we blindly set FEATURES_OK and later FAILED.  Support this better
by adding a callback drivers can use to do some early checks.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-07 16:38:59 +03:00
Arnd Bergmann f0bb2d50df virtio_balloon: prevent uninitialized variable use
The latest gcc-7.0.1 snapshot reports a new warning:

virtio/virtio_balloon.c: In function 'update_balloon_stats':
virtio/virtio_balloon.c:258:26: error: 'events[2]' is used uninitialized in this function [-Werror=uninitialized]
virtio/virtio_balloon.c:260:26: error: 'events[3]' is used uninitialized in this function [-Werror=uninitialized]
virtio/virtio_balloon.c:261:56: error: 'events[18]' is used uninitialized in this function [-Werror=uninitialized]
virtio/virtio_balloon.c:262:56: error: 'events[17]' is used uninitialized in this function [-Werror=uninitialized]

This seems absolutely right, so we should add an extra check to
prevent copying uninitialized stack data into the statistics.
>From all I can tell, this has been broken since the statistics code
was originally added in 2.6.34.

Fixes: 9564e138b1 ("virtio: Add memory statistics reporting to the balloon driver (V4)")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-03-28 20:41:28 +03:00
Ladi Prosek 9646b26e85 virtio-balloon: use actual number of stats for stats queue buffers
The virtio balloon driver contained a not-so-obvious invariant that
update_balloon_stats has to update exactly VIRTIO_BALLOON_S_NR counters
in order to send valid stats to the host. This commit fixes it by having
update_balloon_stats return the actual number of counters, and its
callers use it when pushing buffers to the stats virtqueue.

Note that it is still out of spec to change the number of counters
at run-time. "Driver MUST supply the same subset of statistics in all
buffers submitted to the statsq."

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-03-28 20:41:28 +03:00
Ladi Prosek fc8653228c virtio_balloon: init 1st buffer in stats vq
When init_vqs runs, virtio_balloon.stats is either uninitialized or
contains stale values. The host updates its state with garbage data
because it has no way of knowing that this is just a marker buffer
used for signaling.

This patch updates the stats before pushing the initial buffer.

Alternative fixes:
* Push an empty buffer in init_vqs. Not easily done with the current
  virtio implementation and violates the spec "Driver MUST supply the
  same subset of statistics in all buffers submitted to the statsq".
* Push a buffer with invalid tags in init_vqs. Violates the same
  spec clause, plus "invalid tag" is not really defined.

Note: the spec says:
	When using the legacy interface, the device SHOULD ignore all values in
	the first buffer in the statsq supplied by the driver after device
	initialization. Note: Historically, drivers supplied an uninitialized
	buffer in the first buffer.

Unfortunately QEMU does not seem to implement the recommendation
even for the legacy interface.

Cc: stable@vger.kernel.org
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-03-28 20:41:27 +03:00
Jason Wang de85ec8b07 virtio_pci: fix out of bound access for msix_names
Fedora has received multiple reports of crashes when running
4.11 as a guest

https://bugzilla.redhat.com/show_bug.cgi?id=1430297
https://bugzilla.redhat.com/show_bug.cgi?id=1434462
https://bugzilla.kernel.org/show_bug.cgi?id=194911
https://bugzilla.redhat.com/show_bug.cgi?id=1433899

The crashes are not always consistent but they are generally
some flavor of oops or GPF in virtio related code. Multiple people
have done bisections (Thank you Thorsten Leemhuis and
Richard W.M. Jones) and found this commit to be at fault

07ec51480b is the first bad commit
commit 07ec51480b
Author: Christoph Hellwig <hch@lst.de>
Date:   Sun Feb 5 18:15:19 2017 +0100

    virtio_pci: use shared interrupts for virtqueues

The issue seems to be an out of bounds access to the msix_names
array corrupting kernel memory.

Fixes: 07ec51480b ("virtio_pci: use shared interrupts for virtqueues")
Reported-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Tested-by: Thorsten Leemhuis <linux@leemhuis.info>
2017-03-28 20:40:53 +03:00
Linus Torvalds 1827adb11a Merge branch 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull sched.h split-up from Ingo Molnar:
 "The point of these changes is to significantly reduce the
  <linux/sched.h> header footprint, to speed up the kernel build and to
  have a cleaner header structure.

  After these changes the new <linux/sched.h>'s typical preprocessed
  size goes down from a previous ~0.68 MB (~22K lines) to ~0.45 MB (~15K
  lines), which is around 40% faster to build on typical configs.

  Not much changed from the last version (-v2) posted three weeks ago: I
  eliminated quirks, backmerged fixes plus I rebased it to an upstream
  SHA1 from yesterday that includes most changes queued up in -next plus
  all sched.h changes that were pending from Andrew.

  I've re-tested the series both on x86 and on cross-arch defconfigs,
  and did a bisectability test at a number of random points.

  I tried to test as many build configurations as possible, but some
  build breakage is probably still left - but it should be mostly
  limited to architectures that have no cross-compiler binaries
  available on kernel.org, and non-default configurations"

* 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (146 commits)
  sched/headers: Clean up <linux/sched.h>
  sched/headers: Remove #ifdefs from <linux/sched.h>
  sched/headers: Remove the <linux/topology.h> include from <linux/sched.h>
  sched/headers, hrtimer: Remove the <linux/wait.h> include from <linux/hrtimer.h>
  sched/headers, x86/apic: Remove the <linux/pm.h> header inclusion from <asm/apic.h>
  sched/headers, timers: Remove the <linux/sysctl.h> include from <linux/timer.h>
  sched/headers: Remove <linux/magic.h> from <linux/sched/task_stack.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/init.h>
  sched/core: Remove unused prefetch_stack()
  sched/headers: Remove <linux/rculist.h> from <linux/sched.h>
  sched/headers: Remove the 'init_pid_ns' prototype from <linux/sched.h>
  sched/headers: Remove <linux/signal.h> from <linux/sched.h>
  sched/headers: Remove <linux/rwsem.h> from <linux/sched.h>
  sched/headers: Remove the runqueue_is_locked() prototype
  sched/headers: Remove <linux/sched.h> from <linux/sched/hotplug.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/debug.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/nohz.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/stat.h>
  sched/headers: Remove the <linux/gfp.h> include from <linux/sched.h>
  sched/headers: Remove <linux/rtmutex.h> from <linux/sched.h>
  ...
2017-03-03 10:16:38 -08:00
Linus Torvalds 54d7989f47 virtio, vhost: optimizations, fixes
Looks like a quiet cycle for vhost/virtio, just a couple of minor
 tweaks. Most notable is automatic interrupt affinity for blk and scsi.
 Hopefully other devices are not far behind.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull vhost updates from Michael Tsirkin:
 "virtio, vhost: optimizations, fixes

  Looks like a quiet cycle for vhost/virtio, just a couple of minor
  tweaks. Most notable is automatic interrupt affinity for blk and scsi.
  Hopefully other devices are not far behind"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio-console: avoid DMA from stack
  vhost: introduce O(1) vq metadata cache
  virtio_scsi: use virtio IRQ affinity
  virtio_blk: use virtio IRQ affinity
  blk-mq: provide a default queue mapping for virtio device
  virtio: provide a method to get the IRQ affinity mask for a virtqueue
  virtio: allow drivers to request IRQ affinity when creating VQs
  virtio_pci: simplify MSI-X setup
  virtio_pci: don't duplicate the msix_enable flag in struct pci_dev
  virtio_pci: use shared interrupts for virtqueues
  virtio_pci: remove struct virtio_pci_vq_info
  vhost: try avoiding avail index access when getting descriptor
  virtio_mmio: expose header to userspace
2017-03-02 13:53:13 -08:00
Ingo Molnar 50d34394ce sched/headers: Prepare to remove the <linux/magic.h> include from <linux/sched/task_stack.h>
Update files that depend on the magic.h inclusion.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:40 +01:00
Christoph Hellwig bbaba47956 virtio: provide a method to get the IRQ affinity mask for a virtqueue
This basically passed up the pci_irq_get_affinity information through
virtio through an optional get_vq_affinity method.  It is only implemented
by the PCI backend for now, and only when we use per-virtqueue IRQs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27 20:54:05 +02:00
Christoph Hellwig fb5e31d970 virtio: allow drivers to request IRQ affinity when creating VQs
Add a struct irq_affinity pointer to the find_vqs methods, which if set
is used to tell the PCI layer to create the MSI-X vectors for our I/O
virtqueues with the proper affinity from the start.  Compared to after
the fact affinity hints this gives us an instantly working setup and
allows to allocate the irq descritors node-local and avoid interconnect
traffic.  Last but not least this will allow blk-mq queues are created
based on the interrupt affinity for storage drivers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27 20:54:04 +02:00
Christoph Hellwig 52a6151612 virtio_pci: simplify MSI-X setup
Try to grab the MSI-X vectors early and fall back to the shared one
before doing lots of allocations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27 20:54:04 +02:00
Christoph Hellwig 53a020c661 virtio_pci: don't duplicate the msix_enable flag in struct pci_dev
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27 20:54:03 +02:00
Christoph Hellwig 07ec51480b virtio_pci: use shared interrupts for virtqueues
This lets IRQ layer handle dispatching IRQs to separate handlers for the
case where we don't have per-VQ MSI-X vectors, and allows us to greatly
simplify the code based on the assumption that we always have interrupt
vector 0 (legacy INTx or config interrupt for MSI-X) available, and
any other interrupt is request/freed throught the VQ, even if the
actual interrupt line might be shared in some cases.

This allows removing a great deal of variables keeping track of the
interrupt state in struct virtio_pci_device, as we can now simply walk the
list of VQs and deal with per-VQ interrupt handlers there, and only treat
vector 0 special.

Additionally clean up the VQ allocation code to properly unwind on error
instead of having a single global cleanup label, which is error prone,
and in this case also leads to more code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27 20:54:03 +02:00
Christoph Hellwig 5c34d002dc virtio_pci: remove struct virtio_pci_vq_info
We don't really need struct virtio_pci_vq_info, as most field in there
are redundant:

 - the vq backpointer is not strictly neede to start with
 - the entry in the vqs list is not needed - the generic virtqueue already
   has list, we only need to check if it has a callback to get the same
   semantics
 - we can use a simple array to look up the MSI-X vec if needed.
 - That simple array now also duoble serves to replace the per_vq_vectors
   flag

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27 20:54:03 +02:00
Michael S. Tsirkin 51be7a9a26 virtio_mmio: expose header to userspace
It's handy for userspace emulators like QEMU.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27 16:31:23 +02:00
Yisheng Xie 9c57b5808c mm balloon: umount balloon_mnt when removing vb device
With CONFIG_BALLOON_COMPACTION=y the kernel will mount balloon_mnt for
balloon page migration when we probe a virtio_balloon device.  However
we do not unmount it when removing the device.  Fix this.

Fixes: b1123ea6d3 ("mm: balloon: use general non-lru movable page feature")
Link: http://lkml.kernel.org/r/1486531318-35189-1-git-send-email-xieyisheng1@huawei.com
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Gioh Kim <gi-oh.kim@profitbricks.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:56 -08:00
David S. Miller 3efa70d78f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The conflict was an interaction between a bug fix in the
netvsc driver in 'net' and an optimization of the RX path
in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-07 16:29:30 -05:00
John Fastabend 9fe7bfce8b virtio_net: refactor freeze/restore logic into virtnet reset logic
For XDP we will need to reset the queues to allow for buffer headroom
to be configured. In order to do this we need to essentially run the
freeze()/restore() code path. Unfortunately the locking requirements
between the freeze/restore and reset paths are different however so
we can not simply reuse the code.

This patch refactors the code path and adds a reset helper routine.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-07 10:05:12 -05:00
Michael S. Tsirkin 0d5415b489 Revert "vring: Force use of DMA API for ARM-based systems with legacy devices"
This reverts commit c7070619f3.

This has been shown to regress on some ARM systems:

by forcing on DMA API usage for ARM systems, we have inadvertently
kicked open a hornets' nest in terms of cache-coherency. Namely that
unless the virtio device is explicitly described as capable of coherent
DMA by firmware, the DMA APIs on ARM and other DT-based platforms will
assume it is non-coherent. This turns out to cause a big problem for the
likes of QEMU and kvmtool, which generate virtio-mmio devices in their
guest DTs but neglect to add the often-overlooked "dma-coherent"
property; as a result, we end up with the guest making non-cacheable
accesses to the vring, the host doing so cacheably, both talking past
each other and things going horribly wrong.

We are working on a safer work-around.

Fixes: c7070619f3 ("vring: Force use of DMA API for ARM-based systems with legacy devices")
Reported-by: Robin Murphy <robin.murphy@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-03 23:38:50 +02:00
Will Deacon c7070619f3 vring: Force use of DMA API for ARM-based systems with legacy devices
Booting Linux on an ARM fastmodel containing an SMMU emulation results
in an unexpected I/O page fault from the legacy virtio-blk PCI device:

[    1.211721] arm-smmu-v3 2b400000.smmu: event 0x10 received:
[    1.211800] arm-smmu-v3 2b400000.smmu:	0x00000000fffff010
[    1.211880] arm-smmu-v3 2b400000.smmu:	0x0000020800000000
[    1.211959] arm-smmu-v3 2b400000.smmu:	0x00000008fa081002
[    1.212075] arm-smmu-v3 2b400000.smmu:	0x0000000000000000
[    1.212155] arm-smmu-v3 2b400000.smmu: event 0x10 received:
[    1.212234] arm-smmu-v3 2b400000.smmu:	0x00000000fffff010
[    1.212314] arm-smmu-v3 2b400000.smmu:	0x0000020800000000
[    1.212394] arm-smmu-v3 2b400000.smmu:	0x00000008fa081000
[    1.212471] arm-smmu-v3 2b400000.smmu:	0x0000000000000000

<system hangs failing to read partition table>

This is because the legacy virtio-blk device is behind an SMMU, so we
have consequently swizzled its DMA ops and configured the SMMU to
translate accesses. This then requires the vring code to use the DMA API
to establish translations, otherwise all transactions will result in
fatal faults and termination.

Given that ARM-based systems only see an SMMU if one is really present
(the topology is all described by firmware tables such as device-tree or
IORT), then we can safely use the DMA API for all legacy virtio devices.
Modern devices can advertise the prescense of an IOMMU using the
VIRTIO_F_IOMMU_PLATFORM feature flag.

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: <stable@vger.kernel.org>
Fixes: 876945dbf6 ("arm64: Hook up IOMMU dma_ops")
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-25 00:33:11 +02:00
Robin Murphy f7f6634d23 virtio_mmio: Set DMA masks appropriately
Once DMA API usage is enabled, it becomes apparent that virtio-mmio is
inadvertently relying on the default 32-bit DMA mask, which leads to
problems like rapidly exhausting SWIOTLB bounce buffers.

Ensure that we set the appropriate 64-bit DMA mask whenever possible,
with the coherent mask suitably limited for the legacy vring as per
a0be1db430 ("virtio_pci: Limit DMA mask to 44 bits for legacy virtio
devices").

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Reported-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Fixes: b42111382f ("virtio_mmio: Use the DMA API if enabled")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-25 00:33:10 +02:00
Yuan Liu cecdbdc377 virtio_mmio: Set dev.release() to avoid warning
Fix a warning thrown from virtio_mmio_remove():
Device 'virtio0' does not have a release() function

The fix is according to virtio_pci_probe() of
drivers/virtio/virtio_pci_common.c

Signed-off-by: Yuan Liu <liuyuan@google.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-16 00:13:39 +02:00
Felipe Franciosi 0c7eaf5930 virtio_ring: fix description of virtqueue_get_buf
The device (not the driver) populates the used ring and includes the len
of how much data was written.

Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-16 00:13:38 +02:00
Christoph Hellwig a3cbec6972 virtio_pci: split vp_try_to_find_vqs into INTx and MSI-X variants
There is basically no shared logic between the INTx and MSI-X case in
vp_try_to_find_vqs, so split the function into two and clean them up
a little bit.

Also remove the fairly pointless vp_request_intx wrapper while we're at it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-16 00:12:49 +02:00
Christoph Hellwig 66f2f55542 virtio_pci: merge vp_free_vectors into vp_del_vqs
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-16 00:12:48 +02:00
Christoph Hellwig 9f8196cc05 virtio_pci: remove the call to vp_free_vectors in vp_request_msix_vectors
vp_request_msix_vectors is only called by vp_try_to_find_vqs, which already
calls vp_free_vectors through vp_del_vqs in the failure case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-16 00:12:48 +02:00
Christoph Hellwig fa3a327935 virtio_pci: use pci_alloc_irq_vectors
This avoids the separate allocation for the msix_entries structures, and
instead allows us to use pci_irq_vector to find a given IRQ vector.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-16 00:12:47 +02:00
Michael S. Tsirkin d41795978c virtio: clean up handling of request_irq failure
We call del_vqs twice when request_irq fails, this
makes no sense.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-16 00:12:44 +02:00
Gonglei c60923cb9c virtio_ring: fix complaint by sparse
# make C=2 CF="-D__CHECK_ENDIAN__" ./drivers/virtio/

drivers/virtio/virtio_ring.c:423:19: warning: incorrect type in assignment (different base types)
drivers/virtio/virtio_ring.c:423:19:    expected unsigned int [unsigned] [assigned] i
drivers/virtio/virtio_ring.c:423:19:    got restricted __virtio16 [usertype] next
drivers/virtio/virtio_ring.c:423:19: warning: incorrect type in assignment (different base types)
drivers/virtio/virtio_ring.c:423:19:    expected unsigned int [unsigned] [assigned] i
drivers/virtio/virtio_ring.c:423:19:    got restricted __virtio16 [usertype] next
drivers/virtio/virtio_ring.c:423:19: warning: incorrect type in assignment (different base types)
drivers/virtio/virtio_ring.c:423:19:    expected unsigned int [unsigned] [assigned] i
drivers/virtio/virtio_ring.c:423:19:    got restricted __virtio16 [usertype] next
drivers/virtio/virtio_ring.c:604:39: warning: incorrect type in initializer (different base types)
drivers/virtio/virtio_ring.c:604:39:    expected unsigned short [unsigned] [usertype] nextflag
drivers/virtio/virtio_ring.c:604:39:    got restricted __virtio16
drivers/virtio/virtio_ring.c:612:33: warning: restricted __virtio16 degrades to integer

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-15 06:39:47 +02:00
Gonglei 61bd405f4e virtio_pci_modern: fix complaint by sparse
drivers/virtio/virtio_pci_modern.c:66:40: warning: incorrect type in argument 2 (different base types)
drivers/virtio/virtio_pci_modern.c:66:40:    expected unsigned int [noderef] [usertype] <asn:2>*addr
drivers/virtio/virtio_pci_modern.c:66:40:    got restricted __le32 [noderef] [usertype] <asn:2>*lo
drivers/virtio/virtio_pci_modern.c:67:33: warning: incorrect type in argument 2 (different base types)
drivers/virtio/virtio_pci_modern.c:67:33:    expected unsigned int [noderef] [usertype] <asn:2>*addr
drivers/virtio/virtio_pci_modern.c:67:33:    got restricted __le32 [noderef] [usertype] <asn:2>*hi
drivers/virtio/virtio_pci_modern.c:150:32: warning: incorrect type in argument 2 (different base types)
drivers/virtio/virtio_pci_modern.c:150:32:    expected unsigned int [noderef] [usertype] <asn:2>*addr
drivers/virtio/virtio_pci_modern.c:150:32:    got restricted __le32 [noderef] <asn:2>*<noident>
drivers/virtio/virtio_pci_modern.c:151:39: warning: incorrect type in argument 1 (different base types)
drivers/virtio/virtio_pci_modern.c:151:39:    expected unsigned int [noderef] [usertype] <asn:2>*addr
drivers/virtio/virtio_pci_modern.c:151:39:    got restricted __le32 [noderef] <asn:2>*<noident>
drivers/virtio/virtio_pci_modern.c:152:32: warning: incorrect type in argument 2 (different base types)
drivers/virtio/virtio_pci_modern.c:152:32:    expected unsigned int [noderef] [usertype] <asn:2>*addr

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-15 06:39:46 +02:00
Jonathan Corbet 917fef6f7e Linux 4.9-rc4
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Merge tag 'v4.9-rc4' into sound

Bring in -rc4 patches so I can successfully merge the sound doc changes.
2016-11-18 16:13:41 -07:00
Michael S. Tsirkin 75bfa81bf0 virtio_ring: mark vring_dma_dev inline
This inline function is unused on configurations
where dma_map/unmap are empty macros.

Make the function inline to avoid gcc errors because
of an unused static function.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-31 00:40:08 +02:00
Juergen Gross 3dae2c6152 virtio: remove config.c
Remove unused file config.c

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-31 00:21:45 +02:00
Konstantin Neumoin 8424af5336 virtio: update balloon size in balloon "probe"
The following commit 'fad7b7b27b6a (virtio_balloon: Use a workqueue
instead of "vballoon" kthread)' has added a regression. Original code with
kthread starts the thread inside probe and checks the necessity to update
balloon inside the thread immediately.

Nowadays the code behaves differently. Work is queued only on the first
command from the host after the negotiation. Thus there is a window
especially at the guest startup or the module reloading when the balloon
size is not updated until the notification from the host.

This patch adds balloon size check at the end of the probe to match
original behaviour.

Signed-off-by: Konstantin Neumoin <kneumoin@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-31 00:21:41 +02:00
Ladi Prosek 0ea1e4a6d9 virtio_ring: Make interrupt suppression spec compliant
According to the spec, if the VIRTIO_RING_F_EVENT_IDX feature bit is
negotiated the driver MUST set flags to 0. Not dirtying the available
ring in virtqueue_disable_cb also has a minor positive performance
impact, improving L1 dcache load missed by ~0.5% in vring_bench.

Writes to the used event field (vring_used_event) are still unconditional.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: <stable@vger.kernel.org> # f277ec4 virtio_ring: shadow available
Cc: <stable@vger.kernel.org>
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-31 00:21:40 +02:00
Will Deacon a0be1db430 virtio_pci: Limit DMA mask to 44 bits for legacy virtio devices
Legacy virtio defines the virtqueue base using a 32-bit PFN field, with
a read-only register indicating a fixed page size of 4k.

This can cause problems for DMA allocators that allocate top down from
the DMA mask, which is set to 64 bits. In this case, the addresses are
silently truncated to 44-bit, leading to IOMMU faults, failure to read
from the queue or data corruption.

This patch restricts the coherent DMA mask for legacy PCI virtio devices
to 44 bits, which matches the specification.

Cc: stable@vger.kernel.org
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Benjamin Serebrin <serebrin@google.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-31 00:21:39 +02:00
Mauro Carvalho Chehab 8c27ceff36 docs: fix locations of several documents that got moved
The previous patch renamed several files that are cross-referenced
along the Kernel documentation. Adjust the links to point to
the right places.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-10-24 08:12:35 -02:00
Baoyou Xie af7c1beccf virtio: mark vring_dma_dev() static
We get 1 warning when building kernel with W=1:
drivers/virtio/virtio_ring.c:170:16: warning: no previous prototype for 'vring_dma_dev' [-Wmissing-prototypes]

In fact, this function is only used in the file in which it is
declared and don't need a declaration, but can be made static.
so this patch marks this function with 'static'.

Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-09-09 21:12:35 +03:00
Michael S. Tsirkin 3cc36f6e34 virtio: fix error handling for debug builds
On error, virtqueue_add calls START_USE but not
END_USE. Thankfully that's normally empty anyway,
but might not be when debugging. Fix it up.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-08-09 13:42:35 +03:00
Wei Yongjun 58625edf9e virtio: fix memory leak in virtqueue_add()
When using the indirect buffers feature, 'desc' is allocated in
virtqueue_add() but isn't freed before leaving on a ring full error,
causing a memory leak.

For example, it seems rather clear that this can trigger
with virtio net if mergeable buffers are not used.

Cc: stable@vger.kernel.org
Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-08-09 13:42:34 +03:00
Linus Torvalds 0803e04011 virtio/vhost: new features for 4.8
- New vsock device support in host and guest
 - Platform IOMMU support in host and guest,
   including compatibility quirks for legacy systems.
 - Misc fixes and cleanups.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio/vhost updates from Michael Tsirkin:

 - new vsock device support in host and guest

 - platform IOMMU support in host and guest, including compatibility
   quirks for legacy systems.

 - misc fixes and cleanups.

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  VSOCK: Use kvfree()
  vhost: split out vringh Kconfig
  vhost: detect 32 bit integer wrap around
  vhost: new device IOTLB API
  vhost: drop vringh dependency
  vhost: convert pre sorted vhost memory array to interval tree
  vhost: introduce vhost memory accessors
  VSOCK: Add Makefile and Kconfig
  VSOCK: Introduce vhost_vsock.ko
  VSOCK: Introduce virtio_transport.ko
  VSOCK: Introduce virtio_vsock_common.ko
  VSOCK: defer sock removal to transports
  VSOCK: transport-specific vsock_transport functions
  vhost: drop vringh dependency
  vop: pull in vhost Kconfig
  virtio: new feature to detect IOMMU device quirk
  balloon: check the number of available pages in leak balloon
  vhost: lockless enqueuing
  vhost: simplify work flushing
2016-08-06 09:20:13 -04:00
Michael S. Tsirkin 1a93769399 virtio: new feature to detect IOMMU device quirk
The interaction between virtio and IOMMUs is messy.

On most systems with virtio, physical addresses match bus addresses,
and it doesn't particularly matter which one we use to program
the device.

On some systems, including Xen and any system with a physical device
that speaks virtio behind a physical IOMMU, we must program the IOMMU
for virtio DMA to work at all.

On other systems, including SPARC and PPC64, virtio-pci devices are
enumerated as though they are behind an IOMMU, but the virtio host
ignores the IOMMU, so we must either pretend that the IOMMU isn't
there or somehow map everything as the identity.

Add a feature bit to detect that quirk: VIRTIO_F_IOMMU_PLATFORM.

Any device with this feature bit set to 0 needs a quirk and has to be
passed physical addresses (as opposed to bus addresses) even though
the device is behind an IOMMU.

Note: it has to be a per-device quirk because for example, there could
be a mix of passed-through and virtual virtio devices. As another
example, some devices could be implemented by an out of process
hypervisor backend (in case of qemu vhost, or vhost-user) and so support
for an IOMMU needs to be coded up separately.

It would be cleanest to handle this in IOMMU core code, but that needs
per-device DMA ops. While we are waiting for that to be implemented, use
a work-around in virtio core.

Note: a "noiommu" feature is a quirk - add a wrapper to make
that clear.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-08-01 21:44:52 +03:00
Konstantin Neumoin 37cf99e08c balloon: check the number of available pages in leak balloon
The balloon has a special mechanism that is subscribed to the oom
notification which leads to deflation for a fixed number of pages.
The number is always fixed even when the balloon is fully deflated.
But leak_balloon did not expect that the pages to deflate will be more
than taken, and raise a "BUG" in balloon_page_dequeue when page list
will be empty.

So, the simplest solution would be to check that the number of releases
pages is less or equal to the number taken pages.

Cc: stable@vger.kernel.org
Signed-off-by: Konstantin Neumoin <kneumoin@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-08-01 21:44:51 +03:00
Minchan Kim dd4123f324 mm: fix build warnings in <linux/compaction.h>
Randy reported below build error.

> In file included from ../include/linux/balloon_compaction.h:48:0,
>                  from ../mm/balloon_compaction.c:11:
> ../include/linux/compaction.h:237:51: warning: 'struct node' declared inside parameter list [enabled by default]
>  static inline int compaction_register_node(struct node *node)
> ../include/linux/compaction.h:237:51: warning: its scope is only this definition or declaration, which is probably not what you want [enabled by default]
> ../include/linux/compaction.h:242:54: warning: 'struct node' declared inside parameter list [enabled by default]
>  static inline void compaction_unregister_node(struct node *node)
>

It was caused by non-lru page migration which needs compaction.h but
compaction.h doesn't include any header to be standalone.

I think proper header for non-lru page migration is migrate.h rather
than compaction.h because migrate.h has already headers needed to work
non-lru page migration indirectly like isolate_mode_t, migrate_mode
MIGRATEPAGE_SUCCESS.

[akpm@linux-foundation.org: revert mm-balloon-use-general-non-lru-movable-page-feature-fix.patch temp fix]
Link: http://lkml.kernel.org/r/20160610003304.GE29779@bbox
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Gioh Kim <gi-oh.kim@profitbricks.com>
Cc: Rafael Aquini <aquini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 16:19:19 -07:00
Minchan Kim b1123ea6d3 mm: balloon: use general non-lru movable page feature
Now, VM has a feature to migrate non-lru movable pages so balloon
doesn't need custom migration hooks in migrate.c and compaction.c.

Instead, this patch implements the page->mapping->a_ops->
{isolate|migrate|putback} functions.

With that, we could remove hooks for ballooning in general migration
functions and make balloon compaction simple.

[akpm@linux-foundation.org: compaction.h requires that the includer first include node.h]
Link: http://lkml.kernel.org/r/1464736881-24886-4-git-send-email-minchan@kernel.org
Signed-off-by: Gioh Kim <gi-oh.kim@profitbricks.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 16:19:19 -07:00
Michael S. Tsirkin 87c9403b0d virtio_balloon: fix PFN format for virtio-1
Everything should be LE when using virtio-1, but
the linux balloon driver does not seem to care about that.

Reported-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-05-22 19:44:13 +03:00
Dan Carpenter e00f7bd221 virtio: Silence uninitialized variable warning
Smatch complains that we might not initialize "queue".  The issue is
callers like setup_vq() from virtio_pci_modern.c where "num" could be
something like 2 and "vring_align" is 64.  In that case, vring_size() is
less than PAGE_SIZE.  It won't happen in real life, but we're getting
the value of "num" from a register so it's not really possible to tell
what value it holds with static analysis.

Let's just silence the warning.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-05-01 15:50:08 +03:00
Michael S. Tsirkin 05dbcb4307 virtio: virtio 1.0 cs04 spec compliance for reset
The spec says: after writing 0 to device_status, the driver MUST wait
for a read of device_status to return 0 before reinitializing the
device.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2016-04-07 15:16:39 +03:00
Linus Torvalds f0691533b7 virtio/vhost: new features, performance improvements, cleanups
This adds basic polling support for vhost.
 Reworks virtio to optionally use DMA API, fixing it on Xen.
 Balloon stats gained a new entry.
 Using the new napi_alloc_skb speeds up virtio net.
 virtio blk stats can now be read while another VCPU
 us busy inflating or deflating the balloon.
 Plus misc cleanups in various places.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio/vhost updates from Michael Tsirkin:
 "New features, performance improvements, cleanups:

   - basic polling support for vhost
   - rework virtio to optionally use DMA API, fixing it on Xen
   - balloon stats gained a new entry
   - using the new napi_alloc_skb speeds up virtio net
   - virtio blk stats can now be read while another VCPU is busy
     inflating or deflating the balloon

  plus misc cleanups in various places"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_net: replace netdev_alloc_skb_ip_align() with napi_alloc_skb()
  vhost_net: basic polling support
  vhost: introduce vhost_vq_avail_empty()
  vhost: introduce vhost_has_work()
  virtio_balloon: Allow to resize and update the balloon stats in parallel
  virtio_balloon: Use a workqueue instead of "vballoon" kthread
  virtio/s390: size of SET_IND payload
  virtio/s390: use dev_to_virtio
  vhost: rename vhost_init_used()
  vhost: rename cross-endian helpers
  virtio_blk: VIRTIO_BLK_F_WCE->VIRTIO_BLK_F_FLUSH
  vring: Use the DMA API on Xen
  virtio_pci: Use the DMA API if enabled
  virtio_mmio: Use the DMA API if enabled
  virtio: Add improved queue allocation API
  virtio_ring: Support DMA APIs
  vring: Introduce vring_use_dma_api()
  s390/dma: Allow per device dma ops
  alpha/dma: use common noop dma ops
  dma: Provide simple noop dma ops
2016-03-20 13:28:18 -07:00
Igor Redko 5057dcd0f1 virtio_balloon: export 'available' memory to balloon statistics
Add a new field, VIRTIO_BALLOON_S_AVAIL, to virtio_balloon memory
statistics protocol, corresponding to 'Available' in /proc/meminfo.

It indicates to the hypervisor how big the balloon can be inflated
without pushing the guest system to swap.

Signed-off-by: Igor Redko <redkoi@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Linus Torvalds 63e30271b0 PCI changes for the v4.6 merge window:
Enumeration
     Disable IO/MEM decoding for devices with non-compliant BARs (Bjorn Helgaas)
     Mark Broadwell-EP Home Agent & PCU as having non-compliant BARs (Bjorn Helgaas
 
   Resource management
     Mark shadow copy of VGA ROM as IORESOURCE_PCI_FIXED (Bjorn Helgaas)
     Don't assign or reassign immutable resources (Bjorn Helgaas)
     Don't enable/disable ROM BAR if we're using a RAM shadow copy (Bjorn Helgaas)
     Set ROM shadow location in arch code, not in PCI core (Bjorn Helgaas)
     Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs (Bjorn Helgaas)
     ia64: Use ioremap() instead of open-coded equivalent (Bjorn Helgaas)
     ia64: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
     MIPS: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
     Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY (Bjorn Helgaas)
     Don't leak memory if sysfs_create_bin_file() fails (Bjorn Helgaas)
     rcar: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)
     designware: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)
 
   Virtualization
     Wait for up to 1000ms after FLR reset (Alex Williamson)
     Support SR-IOV on any function type (Kelly Zytaruk)
     Add ACS quirk for all Cavium devices (Manish Jaggi)
 
   AER
     Rename pci_ops_aer to aer_inj_pci_ops (Bjorn Helgaas)
     Restore pci_ops pointer while calling original pci_ops (David Daney)
     Fix aer_inject error codes (Jean Delvare)
     Use dev_warn() in aer_inject (Jean Delvare)
     Log actual error causes in aer_inject (Jean Delvare)
     Log aer_inject error injections (Jean Delvare)
 
   VPD
     Prevent VPD access for buggy devices (Babu Moger)
     Move pci_read_vpd() and pci_write_vpd() close to other VPD code (Bjorn Helgaas)
     Move pci_vpd_release() from header file to pci/access.c (Bjorn Helgaas)
     Remove struct pci_vpd_ops.release function pointer (Bjorn Helgaas)
     Rename VPD symbols to remove unnecessary "pci22" (Bjorn Helgaas)
     Fold struct pci_vpd_pci22 into struct pci_vpd (Bjorn Helgaas)
     Sleep rather than busy-wait for VPD access completion (Bjorn Helgaas)
     Update VPD definitions (Hannes Reinecke)
     Allow access to VPD attributes with size 0 (Hannes Reinecke)
     Determine actual VPD size on first access (Hannes Reinecke)
 
   Generic host bridge driver
     Move structure definitions to separate header file (David Daney)
     Add pci_host_common_probe(), based on gen_pci_probe() (David Daney)
     Expose pci_host_common_probe() for use by other drivers (David Daney)
 
   Altera host bridge driver
     Fix altera_pcie_link_is_up() (Ley Foon Tan)
 
   Cavium ThunderX host bridge driver
     Add PCIe host driver for ThunderX processors (David Daney)
     Add driver for ThunderX-pass{1,2} on-chip devices (David Daney)
 
   Freescale i.MX6 host bridge driver
     Add DT bindings to configure PHY Tx driver settings (Justin Waters)
     Move imx6_pcie_reset_phy() near other PHY handling functions (Lucas Stach)
     Move PHY reset into imx6_pcie_establish_link() (Lucas Stach)
     Remove broken Gen2 workaround (Lucas Stach)
     Move link up check into imx6_pcie_wait_for_link() (Lucas Stach)
 
   Freescale Layerscape host bridge driver
     Add "fsl,ls2085a-pcie" compatible ID (Yang Shi)
 
   Intel VMD host bridge driver
     Attach VMD resources to parent domain's resource tree (Jon Derrick)
     Set bus resource start to 0 (Keith Busch)
 
   Microsoft Hyper-V host bridge driver
     Add fwnode_handle to x86 pci_sysdata (Jake Oshins)
     Look up IRQ domain by fwnode_handle (Jake Oshins)
     Add paravirtual PCI front-end for Microsoft Hyper-V VMs (Jake Oshins)
 
   NVIDIA Tegra host bridge driver
     Add pci_ops.{add,remove}_bus() callbacks (Thierry Reding)
     Implement ->{add,remove}_bus() callbacks (Thierry Reding)
     Remove unused struct tegra_pcie.num_ports field (Thierry Reding)
     Track bus -> CPU mapping (Thierry Reding)
     Remove misleading PHYS_OFFSET (Thierry Reding)
 
   Renesas R-Car host bridge driver
     Depend on ARCH_RENESAS, not ARCH_SHMOBILE (Simon Horman)
 
   Synopsys DesignWare host bridge driver
     ARC: Add PCI support (Joao Pinto)
     Add generic dw_pcie_wait_for_link() (Joao Pinto)
     Add default link up check if sub-driver doesn't override (Joao Pinto)
     Add driver for prototyping kits based on ARC SDP (Joao Pinto)
 
   TI Keystone host bridge driver
     Defer probing if devm_phy_get() returns -EPROBE_DEFER (Shawn Lin)
 
   Xilinx AXI host bridge driver
     Use of_pci_get_host_bridge_resources() to parse DT (Bharat Kumar Gogada)
     Remove dependency on ARM-specific struct hw_pci (Bharat Kumar Gogada)
     Don't call pci_fixup_irqs() on Microblaze (Bharat Kumar Gogada)
     Update Zynq binding with Microblaze node (Bharat Kumar Gogada)
     microblaze: Support generic Xilinx AXI PCIe Host Bridge IP driver (Bharat Kumar Gogada)
 
   Xilinx NWL host bridge driver
     Add support for Xilinx NWL PCIe Host Controller (Bharat Kumar Gogada)
 
   Miscellaneous
     Check device_attach() return value always (Bjorn Helgaas)
     Move pci_set_flags() from asm-generic/pci-bridge.h to linux/pci.h (Bjorn Helgaas)
     Remove includes of empty asm-generic/pci-bridge.h (Bjorn Helgaas)
     ARM64: Remove generated include of asm-generic/pci-bridge.h (Bjorn Helgaas)
     Remove empty asm-generic/pci-bridge.h (Bjorn Helgaas)
     Remove includes of asm/pci-bridge.h (Bjorn Helgaas)
     Consolidate PCI DMA constants and interfaces in linux/pci-dma-compat.h (Bjorn Helgaas)
     unicore32: Remove unused HAVE_ARCH_PCI_SET_DMA_MASK definition (Bjorn Helgaas)
     Cleanup pci/pcie/Kconfig whitespace (Andreas Ziegler)
     Include pci/hotplug Kconfig directly from pci/Kconfig (Bjorn Helgaas)
     Include pci/pcie/Kconfig directly from pci/Kconfig (Bogicevic Sasa)
     frv: Remove stray pci_{alloc,free}_consistent() declaration (Christoph Hellwig)
     Move pci_dma_* helpers to common code (Christoph Hellwig)
     Add PCI_CLASS_SERIAL_USB_DEVICE definition (Heikki Krogerus)
     Add QEMU top-level IDs for (sub)vendor & device (Robin H. Johnson)
     Fix broken URL for Dell biosdevname (Naga Venkata Sai Indubhaskar Jupudi)
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Merge tag 'pci-v4.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:
 "PCI changes for v4.6:

  Enumeration:
   - Disable IO/MEM decoding for devices with non-compliant BARs (Bjorn Helgaas)
   - Mark Broadwell-EP Home Agent & PCU as having non-compliant BARs (Bjorn Helgaas

  Resource management:
   - Mark shadow copy of VGA ROM as IORESOURCE_PCI_FIXED (Bjorn Helgaas)
   - Don't assign or reassign immutable resources (Bjorn Helgaas)
   - Don't enable/disable ROM BAR if we're using a RAM shadow copy (Bjorn Helgaas)
   - Set ROM shadow location in arch code, not in PCI core (Bjorn Helgaas)
   - Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs (Bjorn Helgaas)
   - ia64: Use ioremap() instead of open-coded equivalent (Bjorn Helgaas)
   - ia64: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
   - MIPS: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
   - Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY (Bjorn Helgaas)
   - Don't leak memory if sysfs_create_bin_file() fails (Bjorn Helgaas)
   - rcar: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)
   - designware: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)

  Virtualization:
   - Wait for up to 1000ms after FLR reset (Alex Williamson)
   - Support SR-IOV on any function type (Kelly Zytaruk)
   - Add ACS quirk for all Cavium devices (Manish Jaggi)

  AER:
   - Rename pci_ops_aer to aer_inj_pci_ops (Bjorn Helgaas)
   - Restore pci_ops pointer while calling original pci_ops (David Daney)
   - Fix aer_inject error codes (Jean Delvare)
   - Use dev_warn() in aer_inject (Jean Delvare)
   - Log actual error causes in aer_inject (Jean Delvare)
   - Log aer_inject error injections (Jean Delvare)

  VPD:
   - Prevent VPD access for buggy devices (Babu Moger)
   - Move pci_read_vpd() and pci_write_vpd() close to other VPD code (Bjorn Helgaas)
   - Move pci_vpd_release() from header file to pci/access.c (Bjorn Helgaas)
   - Remove struct pci_vpd_ops.release function pointer (Bjorn Helgaas)
   - Rename VPD symbols to remove unnecessary "pci22" (Bjorn Helgaas)
   - Fold struct pci_vpd_pci22 into struct pci_vpd (Bjorn Helgaas)
   - Sleep rather than busy-wait for VPD access completion (Bjorn Helgaas)
   - Update VPD definitions (Hannes Reinecke)
   - Allow access to VPD attributes with size 0 (Hannes Reinecke)
   - Determine actual VPD size on first access (Hannes Reinecke)

  Generic host bridge driver:
   - Move structure definitions to separate header file (David Daney)
   - Add pci_host_common_probe(), based on gen_pci_probe() (David Daney)
   - Expose pci_host_common_probe() for use by other drivers (David Daney)

  Altera host bridge driver:
   - Fix altera_pcie_link_is_up() (Ley Foon Tan)

  Cavium ThunderX host bridge driver:
   - Add PCIe host driver for ThunderX processors (David Daney)
   - Add driver for ThunderX-pass{1,2} on-chip devices (David Daney)

  Freescale i.MX6 host bridge driver:
   - Add DT bindings to configure PHY Tx driver settings (Justin Waters)
   - Move imx6_pcie_reset_phy() near other PHY handling functions (Lucas Stach)
   - Move PHY reset into imx6_pcie_establish_link() (Lucas Stach)
   - Remove broken Gen2 workaround (Lucas Stach)
   - Move link up check into imx6_pcie_wait_for_link() (Lucas Stach)

  Freescale Layerscape host bridge driver:
   - Add "fsl,ls2085a-pcie" compatible ID (Yang Shi)

  Intel VMD host bridge driver:
   - Attach VMD resources to parent domain's resource tree (Jon Derrick)
   - Set bus resource start to 0 (Keith Busch)

  Microsoft Hyper-V host bridge driver:
   - Add fwnode_handle to x86 pci_sysdata (Jake Oshins)
   - Look up IRQ domain by fwnode_handle (Jake Oshins)
   - Add paravirtual PCI front-end for Microsoft Hyper-V VMs (Jake Oshins)

  NVIDIA Tegra host bridge driver:
   - Add pci_ops.{add,remove}_bus() callbacks (Thierry Reding)
   - Implement ->{add,remove}_bus() callbacks (Thierry Reding)
   - Remove unused struct tegra_pcie.num_ports field (Thierry Reding)
   - Track bus -> CPU mapping (Thierry Reding)
   - Remove misleading PHYS_OFFSET (Thierry Reding)

  Renesas R-Car host bridge driver:
   - Depend on ARCH_RENESAS, not ARCH_SHMOBILE (Simon Horman)

  Synopsys DesignWare host bridge driver:
   - ARC: Add PCI support (Joao Pinto)
   - Add generic dw_pcie_wait_for_link() (Joao Pinto)
   - Add default link up check if sub-driver doesn't override (Joao Pinto)
   - Add driver for prototyping kits based on ARC SDP (Joao Pinto)

  TI Keystone host bridge driver:
   - Defer probing if devm_phy_get() returns -EPROBE_DEFER (Shawn Lin)

  Xilinx AXI host bridge driver:
   - Use of_pci_get_host_bridge_resources() to parse DT (Bharat Kumar Gogada)
   - Remove dependency on ARM-specific struct hw_pci (Bharat Kumar Gogada)
   - Don't call pci_fixup_irqs() on Microblaze (Bharat Kumar Gogada)
   - Update Zynq binding with Microblaze node (Bharat Kumar Gogada)
   - microblaze: Support generic Xilinx AXI PCIe Host Bridge IP driver (Bharat Kumar Gogada)

  Xilinx NWL host bridge driver:
   - Add support for Xilinx NWL PCIe Host Controller (Bharat Kumar Gogada)

  Miscellaneous:
   - Check device_attach() return value always (Bjorn Helgaas)
   - Move pci_set_flags() from asm-generic/pci-bridge.h to linux/pci.h (Bjorn Helgaas)
   - Remove includes of empty asm-generic/pci-bridge.h (Bjorn Helgaas)
   - ARM64: Remove generated include of asm-generic/pci-bridge.h (Bjorn Helgaas)
   - Remove empty asm-generic/pci-bridge.h (Bjorn Helgaas)
   - Remove includes of asm/pci-bridge.h (Bjorn Helgaas)
   - Consolidate PCI DMA constants and interfaces in linux/pci-dma-compat.h (Bjorn Helgaas)
   - unicore32: Remove unused HAVE_ARCH_PCI_SET_DMA_MASK definition (Bjorn Helgaas)
   - Cleanup pci/pcie/Kconfig whitespace (Andreas Ziegler)
   - Include pci/hotplug Kconfig directly from pci/Kconfig (Bjorn Helgaas)
   - Include pci/pcie/Kconfig directly from pci/Kconfig (Bogicevic Sasa)
   - frv: Remove stray pci_{alloc,free}_consistent() declaration (Christoph Hellwig)
   - Move pci_dma_* helpers to common code (Christoph Hellwig)
   - Add PCI_CLASS_SERIAL_USB_DEVICE definition (Heikki Krogerus)
   - Add QEMU top-level IDs for (sub)vendor & device (Robin H. Johnson)
   - Fix broken URL for Dell biosdevname (Naga Venkata Sai Indubhaskar Jupudi)"

* tag 'pci-v4.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (94 commits)
  PCI: Add PCI_CLASS_SERIAL_USB_DEVICE definition
  PCI: designware: Add driver for prototyping kits based on ARC SDP
  PCI: designware: Add default link up check if sub-driver doesn't override
  PCI: designware: Add generic dw_pcie_wait_for_link()
  PCI: Cleanup pci/pcie/Kconfig whitespace
  PCI: Simplify pci_create_attr() control flow
  PCI: Don't leak memory if sysfs_create_bin_file() fails
  PCI: Simplify sysfs ROM cleanup
  PCI: Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY
  MIPS: Loongson 3: Keep CPU physical (not virtual) addresses in shadow ROM resource
  MIPS: Loongson 3: Use temporary struct resource * to avoid repetition
  ia64/PCI: Keep CPU physical (not virtual) addresses in shadow ROM resource
  ia64/PCI: Use ioremap() instead of open-coded equivalent
  ia64/PCI: Use temporary struct resource * to avoid repetition
  PCI: Clean up pci_map_rom() whitespace
  PCI: Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs
  PCI: thunder: Add driver for ThunderX-pass{1,2} on-chip devices
  PCI: thunder: Add PCIe host driver for ThunderX processors
  PCI: generic: Expose pci_host_common_probe() for use by other drivers
  PCI: generic: Add pci_host_common_probe(), based on gen_pci_probe()
  ...
2016-03-16 14:45:55 -07:00
Petr Mladek fd0e21c31e virtio_balloon: Allow to resize and update the balloon stats in parallel
The virtio balloon statistics are not updated when the balloon
is being resized. But it seems that both tasks could be done
in parallel.

stats_handle_request() updates the statistics in the balloon
structure and then communicates with the host.

update_balloon_stats() calls all_vm_events() that just reads
some per-CPU variables. The values might change during and
after the call but it is expected and happens even without
this patch.

update_balloon_stats() also calls si_meminfo(). It is a bit
more complex function. It too just reads some variables and
looks lock-less safe. In each case, it seems to be called
lock-less on several similar locations, e.g. from post_status()
in dm_thread_func(), or from vmballoon_send_get_target().

The communication with the host is done via a separate virtqueue,
see vb->stats_vq vs. vb->inflate_vq and vb->deflate_vq. Therefore
it could be used in parallel with fill_balloon() and leak_balloon().

This patch splits the existing work into two pieces. One is for
updating the balloon stats. The other is for resizing of the balloon.
It seems that they can be proceed in parallel without any
extra locking.

Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-03-11 01:40:18 +02:00
Petr Mladek fad7b7b27b virtio_balloon: Use a workqueue instead of "vballoon" kthread
This patch moves the deferred work from the "vballoon" kthread into a
system freezable workqueue.

We do not need to maintain and run a dedicated kthread. Also the event
driven workqueues API makes the logic much easier. Especially, we do
not longer need an own wait queue, wait function, and freeze point.

The conversion is pretty straightforward. One cycle of the main loop
is put into a work. The work is queued instead of waking the kthread.

fill_balloon() and leak_balloon() have a limit for the amount of modified
pages. The work re-queues itself when necessary. For this, we make
fill_balloon() to return the number of really modified pages.
Note that leak_balloon() already did this.

virtballoon_restore() queues the work only when really needed.

The only complication is that we need to prevent queuing the work
when the balloon is being removed. It was easier before because the
kthread simply removed itself from the wait queue. We need an
extra boolean and spin lock now.

My initial idea was to use a dedicated workqueue. Michael S. Tsirkin
suggested using a system one. Tejun Heo confirmed that the system
workqueue has a pretty high concurrency level (256) by default.
Therefore we need not be afraid of too long blocking.

Signed-off-by: Petr Mladek <pmladek@suse.cz>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-03-11 01:40:13 +02:00
Robin H. Johnson caf02abf9b PCI: Add QEMU top-level IDs for (sub)vendor & device
Introduce PCI_VENDOR/PCI_SUBVENDOR/PCI_SUBDEVICE defines to replace the
constants scattered in the kernel already used to detect QEMU.

They are defined in the QEMU codebase per docs/specs/pci-ids.txt.

Signed-off-by: Robin H. Johnson <robbat2@gentoo.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2016-03-08 22:31:21 -06:00
Andy Lutomirski 78fe398723 vring: Use the DMA API on Xen
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
2016-03-02 17:01:59 +02:00
Andy Lutomirski 7a5589b240 virtio_pci: Use the DMA API if enabled
This switches to vring_create_virtqueue, simplifying the driver and
adding DMA API support.

This fixes virtio-pci on platforms and busses that have IOMMUs.  This
will break the experimental QEMU Q35 IOMMU support until QEMU is
fixed.  In exchange, it fixes physical virtio hardware as well as
virtio-pci running under Xen.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-03-02 17:01:58 +02:00
Andy Lutomirski b42111382f virtio_mmio: Use the DMA API if enabled
This switches to vring_create_virtqueue, simplifying the driver and
adding DMA API support.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-03-02 17:01:58 +02:00
Andy Lutomirski 2a2d1382fe virtio: Add improved queue allocation API
This leaves vring_new_virtqueue alone for compatbility, but it
adds two new improved APIs:

vring_create_virtqueue: Creates a virtqueue backed by automatically
allocated coherent memory.  (Some day it this could be extended to
support non-coherent memory, too, if there ends up being a platform
on which it's worthwhile.)

__vring_new_virtqueue: Creates a virtqueue with a manually-specified
layout.  This should allow mic_virtio to work much more cleanly.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-03-02 17:01:57 +02:00
Andy Lutomirski 780bc7903a virtio_ring: Support DMA APIs
virtio_ring currently sends the device (usually a hypervisor)
physical addresses of its I/O buffers.  This is okay when DMA
addresses and physical addresses are the same thing, but this isn't
always the case.  For example, this never works on Xen guests, and
it is likely to fail if a physical "virtio" device ever ends up
behind an IOMMU or swiotlb.

The immediate use case for me is to enable virtio on Xen guests.
For that to work, we need vring to support DMA address translation
as well as a corresponding change to virtio_pci or to another
driver.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-03-02 17:01:57 +02:00
Andy Lutomirski d26c96c810 vring: Introduce vring_use_dma_api()
This is a kludge, but no one has come up with a a better idea yet.
We'll introduce DMA API support guarded by vring_use_dma_api().
Eventually we may be able to return true on more and more systems,
and hopefully we can get rid of vring_use_dma_api() entirely some
day.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-03-02 17:01:56 +02:00
Ladi Prosek 4e94ebdd06 virtio-pci: read the right virtio_pci_notify_cap field
Looks like a copy-paste bug. The value is used as an optimization and a
wrong value probably isn't causing any serious damage. Found when
porting this code to Windows.

Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-03-02 17:01:49 +02:00
Michael S. Tsirkin 2989be09a8 virtio_pci: fix use after free on release
KASan detected a use-after-free error in virtio-pci remove code. In
virtio_pci_remove(), vp_dev is still used after being freed in
unregister_virtio_device() (in virtio_pci_release_dev() more
precisely).

To fix, keep a reference until cleanup is done.

Fixes: 63bd62a08c ("virtio_pci: defer kfree until release callback")
Reported-by: Jerome Marchand <jmarchan@redhat.com>
Cc: stable@vger.kernel.org
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Jerome Marchand <jmarchan@redhat.com>
2016-01-26 10:18:28 +02:00
Stefan Hajnoczi f7ad26ff95 virtio: make find_vqs() checkpatch.pl-friendly
checkpatch.pl wants arrays of strings declared as follows:

  static const char * const names[] = { "vq-1", "vq-2", "vq-3" };

Currently the find_vqs() function takes a const char *names[] argument
so passing checkpatch.pl's const char * const names[] results in a
compiler error due to losing the second const.

This patch adjusts the find_vqs() prototype and updates all virtio
transports.  This makes it possible for virtio_balloon.c, virtio_input.c,
virtgpu_kms.c, and virtio_rpmsg_bus.c to use the checkpatch.pl-friendly
type.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
2016-01-12 20:47:06 +02:00
Minchan Kim f68b992bbb virtio_balloon: fix race by fill and leak
During my compaction-related stuff, I encountered a bug
with ballooning.

With repeated inflating and deflating cycle, guest memory(
ie, cat /proc/meminfo | grep MemTotal) is decreased and
couldn't be recovered.

The reason is balloon_lock doesn't cover release_pages_balloon
so struct virtio_balloon fields could be overwritten by race
of fill_balloon(e,g, vb->*pfns could be critical).

This patch fixes it in my test.

Cc: <stable@vger.kernel.org>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-01-12 20:47:05 +02:00
Michael S. Tsirkin 788e5b3a5d virtio_ring: use virt_store_mb
We need a full barrier after writing out event index, using
virt_store_mb there seems better than open-coding.  As usual, we need a
wrapper to account for strong barriers.

It's tempting to use this in vhost as well, for that, we'll
need a variant of smp_store_mb that works on __user pointers.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2016-01-12 20:47:02 +02:00
Venkatesh Srinivas f277ec42f3 virtio_ring: shadow available ring flags & index
Improves cacheline transfer flow of available ring header.

Virtqueues are implemented as a pair of rings, one producer->consumer
avail ring and one consumer->producer used ring; preceding the
avail ring in memory are two contiguous u16 fields -- avail->flags
and avail->idx. A producer posts work by writing to avail->idx and
a consumer reads avail->idx.

The flags and idx fields only need to be written by a producer CPU
and only read by a consumer CPU; when the producer and consumer are
running on different CPUs and the virtio_ring code is structured to
only have source writes/sink reads, we can continuously transfer the
avail header cacheline between 'M' states between cores. This flow
optimizes core -> core bandwidth on certain CPUs.

(see: "Software Optimization Guide for AMD Family 15h Processors",
Section 11.6; similar language appears in the 10h guide and should
apply to CPUs w/ exclusive caches, using LLC as a transfer cache)

Unfortunately the existing virtio_ring code issued reads to the
avail->idx and read-modify-writes to avail->flags on the producer.

This change shadows the flags and index fields in producer memory;
the vring code now reads from the shadows and only ever writes to
avail->flags and avail->idx, allowing the cacheline to transfer
core -> core optimally.

In a concurrent version of vring_bench, the time required for
10,000,000 buffer checkout/returns was reduced by ~2% (average
across many runs) on an AMD Piledriver (15h) CPU:

(w/o shadowing):
 Performance counter stats for './vring_bench':
     5,451,082,016      L1-dcache-loads
     ...
       2.221477739 seconds time elapsed

(w/ shadowing):
 Performance counter stats for './vring_bench':
     5,405,701,361      L1-dcache-loads
     ...
       2.168405376 seconds time elapsed

The further away (in a NUMA sense) virtio producers and consumers are
from each other, the more we expect to benefit. Physical implementations
of virtio devices and implementations of virtio where the consumer polls
vring avail indexes (vhost) should also benefit.

Signed-off-by: Venkatesh Srinivas <venkateshs@google.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-12-07 17:28:11 +02:00
Michal Hocko 82107539bb virtio: Do not drop __GFP_HIGH in alloc_indirect
b92b1b89a3 ("virtio: force vring descriptors to be allocated from
lowmem") tried to exclude highmem pages for descriptors so it cleared
__GFP_HIGHMEM from a given gfp mask. The patch also cleared __GFP_HIGH
which doesn't make much sense for this fix because __GFP_HIGH only
controls access to memory reserves and it doesn't have any influence
on the zone selection. Some of the call paths use GFP_ATOMIC and
dropping __GFP_HIGH will reduce their changes for success because the
lack of access to memory reserves.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Mel Gorman <mgorman@techsingularity.net>
2015-12-07 17:28:11 +02:00
Suman Anna c13f99b7e9 virtio: fix memory leak of virtio ida cache layers
The virtio core uses a static ida named virtio_index_ida for
assigning index numbers to virtio devices during registration.
The ida core may allocate some internal idr cache layers and
an ida bitmap upon any ida allocation, and all these layers are
truely freed only upon the ida destruction. The virtio_index_ida
is not destroyed at present, leading to a memory leak when using
the virtio core as a module and atleast one virtio device is
registered and unregistered.

Fix this by invoking ida_destroy() in the virtio core module
exit.

Cc: stable@vger.kernel.org
Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-12-07 17:28:01 +02:00
Denis V. Lunev 997e120843 virtio_balloon: do not change memory amount visible via /proc/meminfo
Balloon device is frequently used as a mean of cooperative memory control
in between guest and host to manage memory overcommitment. This is the
typical case for any hosting workload when KVM guest is provided for
end-user.

Though there is a problem in this setup. The end-user and hosting provider
have signed SLA agreement in which some amount of memory is guaranted for
the guest. The good thing is that this memory will be given to the guest
when the guest will really need it (f.e. with OOM in guest and with
VIRTIO_BALLOON_F_DEFLATE_ON_OOM configuration flag set). The bad thing
is that end-user does not know this.

Balloon by default reduce the amount of memory exposed to the end-user
each time when the page is stolen from guest or returned back by using
adjust_managed_page_count and thus /proc/meminfo shows reduced amount
of memory.

Fortunately the solution is simple, we should just avoid to call
adjust_managed_page_count with VIRTIO_BALLOON_F_DEFLATE_ON_OOM set.

Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-09-08 13:32:11 +03:00
Denis V. Lunev b4d3403732 virtio_ballon: change stub of release_pages_by_pfn
and rename it to release_pages_balloon. The function originally takes
arrays of pfns and now it takes pointer to struct virtio_ballon.
This change is necessary to conditionally call adjust_managed_page_count
in the next patch.

Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-09-08 13:31:51 +03:00
Graeme Gregory 38c4ab8e48 virtio_mmio: add ACPI probing
Added the match table and pointers for ACPI probing to the driver.

This uses the same identifier for virt devices as being used for qemu
ARM64 ACPI support.

d0bf1955a3

Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-09-08 13:30:28 +03:00
Jason Wang df4198b1e0 virtio-input: reset device and detach unused during remove
Spec requires a device reset during cleanup, so do it and avoid warn
in virtio core. And detach unused buffers to avoid memory leak.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-08-06 10:40:35 +03:00
Linus Torvalds 5fc835284d virtio/vhost: cross endian support
I have just queued some more bugfix patches today but none fix regressions and
 none are related to these ones, so it looks like a good time for a merge for
 -rc1.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio/vhost cross endian support from Michael Tsirkin:
 "I have just queued some more bugfix patches today but none fix
  regressions and none are related to these ones, so it looks like a
  good time for a merge for -rc1.

  The motivation for this is support for legacy BE guests on the new LE
  hosts.  There are two redeeming properties that made me merge this:

   - It's a trivial amount of code: since we wrap host/guest accesses
     anyway, almost all of it is well hidden from drivers.

   - Sane platforms would never set flags like VHOST_CROSS_ENDIAN_LEGACY,
     and when it's clear, there's zero overhead (as some point it was
     tested by compiling with and without the patches, got the same
     stripped binary).

  Maybe we could create a Kconfig symbol to enforce the second point:
  prevent people from enabling it eg on x86.  I will look into this"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio-pci: alloc only resources actually used.
  macvtap/tun: cross-endian support for little-endian hosts
  vhost: cross-endian support for legacy devices
  virtio: add explicit big-endian support to memory accessors
  vhost: introduce vhost_is_little_endian() helper
  vringh: introduce vringh_is_little_endian() helper
  macvtap: introduce macvtap_is_little_endian() helper
  tun: add tun_is_little_endian() helper
  virtio: introduce virtio_is_little_endian() helper
2015-07-03 16:02:25 -07:00
Linus Torvalds 02201e3f1b Minor merge needed, due to function move.
Main excitement here is Peter Zijlstra's lockless rbtree optimization to
 speed module address lookup.  He found some abusers of the module lock
 doing that too.
 
 A little bit of parameter work here too; including Dan Streetman's breaking
 up the big param mutex so writing a parameter can load another module (yeah,
 really).  Unfortunately that broke the usual suspects, !CONFIG_MODULES and
 !CONFIG_SYSFS, so those fixes were appended too.
 
 Cheers,
 Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module updates from Rusty Russell:
 "Main excitement here is Peter Zijlstra's lockless rbtree optimization
  to speed module address lookup.  He found some abusers of the module
  lock doing that too.

  A little bit of parameter work here too; including Dan Streetman's
  breaking up the big param mutex so writing a parameter can load
  another module (yeah, really).  Unfortunately that broke the usual
  suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were
  appended too"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits)
  modules: only use mod->param_lock if CONFIG_MODULES
  param: fix module param locks when !CONFIG_SYSFS.
  rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE()
  module: add per-module param_lock
  module: make perm const
  params: suppress unused variable error, warn once just in case code changes.
  modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'.
  kernel/module.c: avoid ifdefs for sig_enforce declaration
  kernel/workqueue.c: remove ifdefs over wq_power_efficient
  kernel/params.c: export param_ops_bool_enable_only
  kernel/params.c: generalize bool_enable_only
  kernel/module.c: use generic module param operaters for sig_enforce
  kernel/params: constify struct kernel_param_ops uses
  sysfs: tightened sysfs permission checks
  module: Rework module_addr_{min,max}
  module: Use __module_address() for module_address_lookup()
  module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING
  module: Optimize __module_address() using a latched RB-tree
  rbtree: Implement generic latch_tree
  seqlock: Introduce raw_read_seqcount_latch()
  ...
2015-07-01 10:49:25 -07:00
Gerd Hoffmann 59a5b0f7bf virtio-pci: alloc only resources actually used.
Move resource allocation from common code to legacy and modern code.
Only request resources actually used, i.e. bar0 in legacy mode and
the bar(s) specified by capabilities in modern mode.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-24 08:15:09 +02:00
Linus Torvalds d8133356e9 PCI changes for the v4.2 merge window:
Enumeration
     - Move pci_ari_enabled() to global header (Alex Williamson)
     - Account for ARI in _PRT lookups (Alex Williamson)
     - Remove unused pci_scan_bus_parented() (Yijing Wang)
 
   Resource management
     - Use host bridge _CRS info on systems with >32 bit addressing (Bjorn Helgaas)
     - Use host bridge _CRS info on Foxconn K8M890-8237A (Bjorn Helgaas)
     - Fix pci_address_to_pio() conversion of CPU address to I/O port (Zhichang Yuan)
     - Add pci_bus_addr_t (Yinghai Lu)
 
   PCI device hotplug
     - Wait for pciehp command completion where necessary (Alex Williamson)
     - Drop pointless ACPI-based "slot detection" check (Rafael J. Wysocki)
     - Check ignore_hotplug for all downstream devices (Rafael J. Wysocki)
     - Propagate the "ignore hotplug" setting to parent (Rafael J. Wysocki)
     - Inline pciehp "handle event" functions into the ISR (Bjorn Helgaas)
     - Clean up pciehp debug logging (Bjorn Helgaas)
 
   Power management
     - Remove redundant PCIe port type checking (Yijing Wang)
     - Add dev->has_secondary_link to track downstream PCIe links (Yijing Wang)
     - Use dev->has_secondary_link to find downstream links for ASPM (Yijing Wang)
     - Drop __pci_disable_link_state() useless "force" parameter (Bjorn Helgaas)
     - Simplify Clock Power Management setting (Bjorn Helgaas)
 
   Virtualization
     - Add ACS quirks for Intel 9-series PCH root ports (Alex Williamson)
     - Add function 1 DMA alias quirk for Marvell 9120 (Sakari Ailus)
 
   MSI
     - Disable MSI at enumeration even if kernel doesn't support MSI (Michael S. Tsirkin)
     - Remove unused pci_msi_off() (Bjorn Helgaas)
     - Rename msi_set_enable(), msix_clear_and_set_ctrl() (Michael S.  Tsirkin)
     - Export pci_msi_set_enable(), pci_msix_clear_and_set_ctrl() (Michael S. Tsirkin)
     - Drop pci_msi_off() calls during probe (Michael S. Tsirkin)
 
   APM X-Gene host bridge driver
     - Add APM X-Gene v1 PCIe MSI/MSIX termination driver (Duc Dang)
     - Add APM X-Gene PCIe MSI DTS nodes (Duc Dang)
     - Disable Configuration Request Retry Status for v1 silicon (Duc Dang)
     - Allow config access to Root Port even when link is down (Duc Dang)
 
   Broadcom iProc host bridge driver
     - Allow override of device tree IRQ mapping function (Hauke Mehrtens)
     - Add BCMA PCIe driver (Hauke Mehrtens)
     - Directly add PCI resources (Hauke Mehrtens)
     - Free resource list after registration (Hauke Mehrtens)
 
   Freescale i.MX6 host bridge driver
     - Add speed change timeout message (Troy Kisky)
     - Rename imx6_pcie_start_link() to imx6_pcie_establish_link() (Bjorn Helgaas)
 
   Freescale Layerscape host bridge driver
     - Use dw_pcie_link_up() consistently (Bjorn Helgaas)
     - Factor out ls_pcie_establish_link() (Bjorn Helgaas)
 
   Marvell MVEBU host bridge driver
     - Remove mvebu_pcie_scan_bus() (Yijing Wang)
 
   NVIDIA Tegra host bridge driver
     - Remove tegra_pcie_scan_bus() (Yijing Wang)
 
   Synopsys DesignWare host bridge driver
     - Consolidate outbound iATU programming functions (Jisheng Zhang)
     - Use iATU0 for cfg and IO, iATU1 for MEM (Jisheng Zhang)
     - Add support for x8 links (Zhou Wang)
     - Wait for link to come up with consistent style (Bjorn Helgaas)
     - Use pci_scan_root_bus() for simplicity (Yijing Wang)
 
   TI DRA7xx host bridge driver
     - Use dw_pcie_link_up() consistently (Bjorn Helgaas)
 
   Miscellaneous
     - Include <linux/pci.h>, not <asm/pci.h> (Bjorn Helgaas)
     - Remove unnecessary #includes of <asm/pci.h> (Bjorn Helgaas)
     - Remove unused pcibios_select_root() (again) (Bjorn Helgaas)
     - Remove unused pci_dma_burst_advice() (Bjorn Helgaas)
     - xen/pcifront: Don't use deprecated function pci_scan_bus_parented() (Arnd Bergmann)
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Merge tag 'pci-v4.2-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:
 "PCI changes for the v4.2 merge window:

  Enumeration
    - Move pci_ari_enabled() to global header (Alex Williamson)
    - Account for ARI in _PRT lookups (Alex Williamson)
    - Remove unused pci_scan_bus_parented() (Yijing Wang)

  Resource management
    - Use host bridge _CRS info on systems with >32 bit addressing (Bjorn Helgaas)
    - Use host bridge _CRS info on Foxconn K8M890-8237A (Bjorn Helgaas)
    - Fix pci_address_to_pio() conversion of CPU address to I/O port (Zhichang Yuan)
    - Add pci_bus_addr_t (Yinghai Lu)

  PCI device hotplug
    - Wait for pciehp command completion where necessary (Alex Williamson)
    - Drop pointless ACPI-based "slot detection" check (Rafael J. Wysocki)
    - Check ignore_hotplug for all downstream devices (Rafael J. Wysocki)
    - Propagate the "ignore hotplug" setting to parent (Rafael J. Wysocki)
    - Inline pciehp "handle event" functions into the ISR (Bjorn Helgaas)
    - Clean up pciehp debug logging (Bjorn Helgaas)

  Power management
    - Remove redundant PCIe port type checking (Yijing Wang)
    - Add dev->has_secondary_link to track downstream PCIe links (Yijing Wang)
    - Use dev->has_secondary_link to find downstream links for ASPM (Yijing Wang)
    - Drop __pci_disable_link_state() useless "force" parameter (Bjorn Helgaas)
    - Simplify Clock Power Management setting (Bjorn Helgaas)

  Virtualization
    - Add ACS quirks for Intel 9-series PCH root ports (Alex Williamson)
    - Add function 1 DMA alias quirk for Marvell 9120 (Sakari Ailus)

  MSI
    - Disable MSI at enumeration even if kernel doesn't support MSI (Michael S. Tsirkin)
    - Remove unused pci_msi_off() (Bjorn Helgaas)
    - Rename msi_set_enable(), msix_clear_and_set_ctrl() (Michael S.  Tsirkin)
    - Export pci_msi_set_enable(), pci_msix_clear_and_set_ctrl() (Michael S. Tsirkin)
    - Drop pci_msi_off() calls during probe (Michael S. Tsirkin)

  APM X-Gene host bridge driver
    - Add APM X-Gene v1 PCIe MSI/MSIX termination driver (Duc Dang)
    - Add APM X-Gene PCIe MSI DTS nodes (Duc Dang)
    - Disable Configuration Request Retry Status for v1 silicon (Duc Dang)
    - Allow config access to Root Port even when link is down (Duc Dang)

  Broadcom iProc host bridge driver
    - Allow override of device tree IRQ mapping function (Hauke Mehrtens)
    - Add BCMA PCIe driver (Hauke Mehrtens)
    - Directly add PCI resources (Hauke Mehrtens)
    - Free resource list after registration (Hauke Mehrtens)

  Freescale i.MX6 host bridge driver
    - Add speed change timeout message (Troy Kisky)
    - Rename imx6_pcie_start_link() to imx6_pcie_establish_link() (Bjorn Helgaas)

  Freescale Layerscape host bridge driver
    - Use dw_pcie_link_up() consistently (Bjorn Helgaas)
    - Factor out ls_pcie_establish_link() (Bjorn Helgaas)

  Marvell MVEBU host bridge driver
    - Remove mvebu_pcie_scan_bus() (Yijing Wang)

  NVIDIA Tegra host bridge driver
    - Remove tegra_pcie_scan_bus() (Yijing Wang)

  Synopsys DesignWare host bridge driver
    - Consolidate outbound iATU programming functions (Jisheng Zhang)
    - Use iATU0 for cfg and IO, iATU1 for MEM (Jisheng Zhang)
    - Add support for x8 links (Zhou Wang)
    - Wait for link to come up with consistent style (Bjorn Helgaas)
    - Use pci_scan_root_bus() for simplicity (Yijing Wang)

  TI DRA7xx host bridge driver
    - Use dw_pcie_link_up() consistently (Bjorn Helgaas)

  Miscellaneous
    - Include <linux/pci.h>, not <asm/pci.h> (Bjorn Helgaas)
    - Remove unnecessary #includes of <asm/pci.h> (Bjorn Helgaas)
    - Remove unused pcibios_select_root() (again) (Bjorn Helgaas)
    - Remove unused pci_dma_burst_advice() (Bjorn Helgaas)
    - xen/pcifront: Don't use deprecated function pci_scan_bus_parented() (Arnd Bergmann)"

* tag 'pci-v4.2-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (58 commits)
  PCI: pciehp: Inline the "handle event" functions into the ISR
  PCI: pciehp: Rename queue_interrupt_event() to pciehp_queue_interrupt_event()
  PCI: pciehp: Make queue_interrupt_event() void
  PCI: xgene: Allow config access to Root Port even when link is down
  PCI: xgene: Disable Configuration Request Retry Status for v1 silicon
  PCI: pciehp: Clean up debug logging
  x86/PCI: Use host bridge _CRS info on systems with >32 bit addressing
  PCI: imx6: Add #define PCIE_RC_LCSR
  PCI: imx6: Use "u32", not "uint32_t"
  PCI: Remove unused pci_scan_bus_parented()
  xen/pcifront: Don't use deprecated function pci_scan_bus_parented()
  PCI: imx6: Add speed change timeout message
  PCI/ASPM: Simplify Clock Power Management setting
  PCI: designware: Wait for link to come up with consistent style
  PCI: layerscape: Factor out ls_pcie_establish_link()
  PCI: layerscape: Use dw_pcie_link_up() consistently
  PCI: dra7xx: Use dw_pcie_link_up() consistently
  x86/PCI: Use host bridge _CRS info on Foxconn K8M890-8237A
  PCI: pciehp: Wait for hotplug command completion where necessary
  PCI: Remove unused pci_dma_burst_advice()
  ...
2015-06-23 13:41:24 -07:00
Jiang Liu 210d150e1f virtio_pci: Clear stale cpumask when setting irq affinity
The cpumask vp_dev->msix_affinity_masks[info->msix_vector] may contain
staled information when vp_set_vq_affinity() gets called, so clear it
before setting the new cpu bit mask.

Cc: stable@vger.kernel.org
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-04 14:47:49 +02:00
Luis R. Rodriguez 9c27847dda kernel/params: constify struct kernel_param_ops uses
Most code already uses consts for the struct kernel_param_ops,
sweep the kernel for the last offending stragglers. Other than
include/linux/moduleparam.h and kernel/params.c all other changes
were generated with the following Coccinelle SmPL patch. Merge
conflicts between trees can be handled with Coccinelle.

In the future git could get Coccinelle merge support to deal with
patch --> fail --> grammar --> Coccinelle --> new patch conflicts
automatically for us on patches where the grammar is available and
the patch is of high confidence. Consider this a feature request.

Test compiled on x86_64 against:

	* allnoconfig
	* allmodconfig
	* allyesconfig

@ const_found @
identifier ops;
@@

const struct kernel_param_ops ops = {
};

@ const_not_found depends on !const_found @
identifier ops;
@@

-struct kernel_param_ops ops = {
+const struct kernel_param_ops ops = {
};

Generated-by: Coccinelle SmPL
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Junio C Hamano <gitster@pobox.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: cocci@systeme.lip6.fr
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-05-28 11:32:10 +09:30
Michael S. Tsirkin c1f4d88abd virtio_pci: drop pci_msi_off() call during probe
The PCI core now disables MSI and MSI-X for all devices during enumeration
regardless of CONFIG_PCI_MSI.  Remove device-specific code to disable
MSI/MSI-X.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-05-07 09:52:21 -05:00
Michael S. Tsirkin 9abbfb486f virtio: drop virtio_device_is_legacy_only
virtio_device_is_legacy_only is now unused, drop
it from core.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-15 12:41:14 +09:30
Michael S. Tsirkin f71d8286c1 virtio_pci: support non-legacy balloon devices
virtio_device_is_legacy_only is always false now,
drop the test from virtio pci.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-15 12:41:13 +09:30
Michael S. Tsirkin a62d547c72 virtio_mmio: support non-legacy balloon devices
virtio_device_is_legacy_only is always false now,
drop the test from virtio mmio.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-15 12:41:12 +09:30
Michael S. Tsirkin 2343dabc60 virtio: balloon might not be a legacy device
We added transitional device support to balloon driver,
so we don't need to black-list it in core anymore.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-15 12:41:11 +09:30
Michael S. Tsirkin df81b29c7b virtio_balloon: transitional interface
Virtio 1.0 doesn't include a modern balloon device.
But it's not a big change to support a transitional
balloon device: this has the advantage of supporting
existing drivers, transparently.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-15 12:41:09 +09:30
Michael S. Tsirkin a8557d32fe virtio_pci_modern: switch to type-safe io accessors
As Rusty noted, we were accessing queue_enable with an incorrect width.
Switch to type-safe accessors so we don't make this mistake again in the
future.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-01 14:43:34 +10:30
Michael S. Tsirkin c5d4c2c9ce virtio_pci_modern: type-safe io accessors
The spec is very clear on this:

4.1.3.1 Driver Requirements: PCI Device Layout

The driver MUST access each field using the “natural” access method,
i.e. 32-bit accesses for 32-bit fields, 16-bit accesses for 16-bit
fields and 8-bit accesses for 8-bit fields.

Add type-safe wrappers to prevent access with incorrect width.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-01 14:37:15 +10:30
Gerd Hoffmann 271c865161 Add virtio-input driver.
virtio-input is basically evdev-events-over-virtio, so this driver isn't
much more than reading configuration from config space and forwarding
incoming events to the linux input layer.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-03-29 12:13:52 +10:30
Michael S. Tsirkin 704a0b5f23 virtio_mmio: fix access width for mmio
Going over the virtio mmio code, I noticed that it doesn't correctly
access modern device config values using "natural" accessors: it uses
readb to get/set them byte by byte, while the virtio 1.0 spec explicitly states:

	4.2.2.2 Driver Requirements: MMIO Device Register Layout

	...

	The driver MUST only use 32 bit wide and aligned reads and writes to
	access the control registers described in table 4.1.
	For the device-specific configuration space, the driver MUST use
	8 bit wide accesses for 8 bit wide fields, 16 bit wide and aligned
	accesses for 16 bit wide fields and 32 bit wide and aligned accesses for
	32 and 64 bit wide fields.

Borrow code from virtio_pci_modern to do this correctly.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-03-17 12:12:21 +10:30
Michael S. Tsirkin 87e7bf1450 virtio_mmio: generation support
virtio_mmio currently lacks generation support which
makes multi-byte field access racy.
Fix by getting the value at offset 0xfc for version 2
devices. Nothing we can do for version 1, so return
generation id 0.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-03-13 15:55:43 +10:30
Michael S. Tsirkin 3d2a3774c1 virtio-balloon: do not call blocking ops when !TASK_RUNNING
virtio balloon has this code:
        wait_event_interruptible(vb->config_change,
                                 (diff = towards_target(vb)) != 0
                                 || vb->need_stats_update
                                 || kthread_should_stop()
                                 || freezing(current));

Which is a problem because towards_target() call might block after
wait_event_interruptible sets task state to TAST_INTERRUPTIBLE, causing
the task_struct::state collision typical of nesting of sleeping
primitives

See also http://lwn.net/Articles/628628/ or Thomas's
bug report
http://article.gmane.org/gmane.linux.kernel.virtualization/24846
for a fuller explanation.

To fix, rewrite using wait_woken.

Cc: stable@vger.kernel.org
Reported-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-03-10 11:56:15 +10:30
Michael S. Tsirkin 88660f7fb9 virtio_balloon: set DRIVER_OK before using device
virtio spec requires that all drivers set DRIVER_OK
before using devices. While balloon isn't yet
included in the virtio 1 spec, previous spec versions
also required this.

virtio balloon might violate this rule: probe calls
kthread_run before setting DRIVER_OK, which might run
immediately and cause balloon to inflate/deflate.

To fix, call virtio_device_ready before running the kthread.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: stable@kernel.org
2015-03-10 11:48:28 +10:30
Rusty Russell 5b40a7daf5 virtio: don't set VIRTIO_CONFIG_S_DRIVER_OK twice.
I noticed this with the console device.  It's not *wrong*, just a bit
weird.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-02-17 16:19:29 +10:30
Rusty Russell 7abb568dbb virtio_pci: use 16-bit accessor for queue_enable.
Since PCI is little endian, 8-bit access might work, but the spec section
is very clear on this:

  4.1.3.1 Driver Requirements: PCI Device Layout

  The driver MUST access each field using the “natural” access method,
  i.e. 32-bit accesses for 32-bit fields, 16-bit accesses for 16-bit
  fields and 8-bit accesses for 8-bit fields.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
2015-02-11 15:03:16 +10:30
Tetsuo Handa 5e05bf5833 virtio: Avoid possible kernel panic if DEBUG is enabled.
The virtqueue_add() calls START_USE() upon entry. The virtqueue_kick() is
called if vq->num_added == (1 << 16) - 1 before calling END_USE().
The virtqueue_kick_prepare() called via virtqueue_kick() calls START_USE()
upon entry, and will call panic() if DEBUG is enabled.
Move this virtqueue_kick() call to after END_USE() call.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-02-11 15:03:14 +10:30
Pawel Moll 1862ee22ce virtio-mmio: Update the device to OASIS spec version
This patch add a support for second version of the virtio-mmio device,
which follows OASIS "Virtual I/O Device (VIRTIO) Version 1.0"
specification.

Main changes:

1. The control register symbolic names use the new device/driver
   nomenclature rather than the old guest/host one.

2. The driver detect the device version (version 1 is the pre-OASIS
   spec, version 2 is compatible with fist revision of the OASIS spec)
   and drives the device accordingly.

3. New version uses direct addressing (64 bit address split into two
   low/high register) instead of the guest page size based one,
   and addresses each part of the queue (descriptors, available, used)
   separately.

4. The device activity is now explicitly triggered by writing to the
   "queue ready" register.

5. Whole 64 bit features are properly handled now (both ways).

Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-23 14:57:10 +10:30
Michael S. Tsirkin 76545f066d virtio_pci_modern: drop an unused function
release function in modern driver is unused:
it's a left-over from when each driver had
to have its own release.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-21 16:29:01 +10:30
Michael S. Tsirkin ac399d8f39 virtio_pci: add module param to force legacy mode
If set, try legacy interface first, modern one if that fails.  Useful to
work around device/driver bugs, and for compatibility testing.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:29:01 +10:30
Michael S. Tsirkin 46506da5f3 virtio_pci: add an option to disable legacy driver
Useful for testing device virtio 1 compatibility.
Based on patch by Rusty - couldn't resist putting
that flying car joke in there!

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:59 +10:30
Michael S. Tsirkin 0327642337 virtio_pci: drop Kconfig warnings
The ABI *is* stable, and has been for a while now.
Drop Kconfig warning saying that it's not guaranteed
to work.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:59 +10:30
Michael S. Tsirkin b2a6d51ddf virtio_pci: Kconfig grammar fix
This drivers -> this driver.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:58 +10:30
Michael S. Tsirkin 43b4f721ce virtio_ring: coding style fix
Most of our code has
struct foo {
}

Fix one instances where ring is inconsistent.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:57 +10:30
Michael S. Tsirkin 25e65e4efc virtio_balloon: coding style fixes
Most of our code has
struct foo {
}

Fix two instances where balloon is inconsistent.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:56 +10:30
Michael S. Tsirkin d3f5f06560 virtio_pci_modern: support devices with no config
Virtio 1.0 spec lists device config as optional.
Set get/set callbacks to NULL. Drivers can check that
and fail gracefully.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:55 +10:30
Michael S. Tsirkin 3909213cfd virtio_pci_modern: reduce number of mappings
We don't know the # of VQs that drivers are going to use so it's hard to
predict how much memory we'll need to map. However, the relevant
capability does give us an upper limit.
If that's below a page, we can reduce the number of required
mappings by mapping it all once ahead of the time.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:55 +10:30
Rusty Russell 89461c4a12 virtio_pci: macros for PCI layout offsets
QEMU wants it, so why not?  Trust, but verify.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-21 16:28:54 +10:30
Michael S. Tsirkin 1fcf0512c9 virtio_pci: modern driver
Lightly tested against qemu.

One thing *not* implemented here is separate mappings
for descriptor/avail/used rings. That's nice to have,
will be done later after we have core support.

This also exposes the PCI layout to userspace, and
adds macros for PCI layout offsets:

QEMU wants it, so why not?  Trust, but verify.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-21 16:28:53 +10:30
Michael S. Tsirkin ff31d2e285 virtio_pci: move probe/remove code to common
Most of initialization is device-independent.
Let's move it to common.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:51 +10:30
Sasha Levin 2bd56afd44 virtio_pci: drop useless del_vqs call
Device VQs were getting freed twice: once in every device's removal
functions, and then again in virtio_pci_legacy_remove().  The ones in
devices are called first, so drop the useless second call.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:50 +10:30
Michael S. Tsirkin 2d9becc1e0 virtio/balloon: verify device has config space
Some devices might not implement config space access
(e.g. remoteproc used not to - before 3.9).
virtio/balloon needs config space access so make it
fail gracefully if not there.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21 16:28:48 +10:30
Michael S. Tsirkin a1eb03f546 virtio_pci: document why we defer kfree
The reason we defer kfree until release function is because it's a
general rule for kobjects: kfree of the reference counter itself is only
legal in the release function.

Previous patch didn't make this clear, document this in code.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-06 16:35:36 +02:00
Sasha Levin 63bd62a08c virtio_pci: defer kfree until release callback
A struct device which has just been unregistered can live on past the
point at which a driver decides to drop it's initial reference to the
kobject gained on allocation.

This implies that when releasing a virtio device, we can't free a struct
virtio_device until the underlying struct device has been released,
which might not happen immediately on device_unregister().

Unfortunately, this is exactly what virtio pci does:
it has an empty release callback, and frees memory immediately
after unregistering the device.

This causes an easy to reproduce crash if CONFIG_DEBUG_KOBJECT_RELEASE
it enabled.

To fix, free the memory only once we know the device is gone in the release
callback.

Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-06 16:35:36 +02:00
Michael S. Tsirkin 945399a8c7 virtio_pci: device-specific release callback
It turns out we need to add device-specific code
in release callback. Move it to virtio_pci_legacy.c.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-06 16:35:36 +02:00
Michael S. Tsirkin 80e9541f79 virtio: make del_vqs idempotent
Our code calls del_vqs multiple times, assuming
it's idempotent.

commit 3ec7a77bb3
    virtio_pci: free up vq->priv
broke this assumption, by adding kfree there,
so multiple calls cause double free.

Fix it up.

Fixes: 3ec7a77bb3
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-06 16:35:35 +02:00
Linus Torvalds 64ec45bff6 vhost/virtio: virtio 1.0 related fixes
Most importantly, this fixes using virtio_pci as a module.
 
 Further, the big virtio 1.0 conversion missed a couple of places. This fixes
 them up.
 
 This isn't 100% sparse-clean yet because on many architectures get_user
 triggers sparse warnings when used with __bitwise tag (when same tag is on both
 pointer and value read).
 
 I posted a patchset to fix it up by adding __force on all
 arches that don't already have it (many do), when that's
 merged these warnings will go away.
 
 Cc: Rusty Russell <rusty@rustcorp.com.au>
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio fixes from Michael S Tsirkin:
 "virtio 1.0 related fixes

  Most importantly, this fixes using virtio_pci as a module.

  Further, the big virtio 1.0 conversion missed a couple of places.
  This fixes them up.

  This isn't 100% sparse-clean yet because on many architectures
  get_user triggers sparse warnings when used with __bitwise tag (when
  same tag is on both pointer and value read).

  I posted a patchset to fix it up by adding __force on all arches that
  don't already have it (many do), when that's merged these warnings
  will go away"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_pci: restore module attributes
  mic/host: fix up virtio 1.0 APIs
  vringh: update for virtio 1.0 APIs
  vringh: 64 bit features
  tools/virtio: add virtio 1.0 in vringh_test
  tools/virtio: add virtio 1.0 in virtio_test
  tools/virtio: enable -Werror
  tools/virtio: 64 bit features
  tools/virtio: fix vringh test
  tools/virtio: more stubs
  virtio: core support for config generation
  virtio_pci: add VIRTIO_PCI_NO_LEGACY
  virtio_pci: move probe to common file
  virtio_pci_common.h: drop VIRTIO_PCI_NO_LEGACY
  virtio_config: fix virtio_cread_bytes
  virtio: set VIRTIO_CONFIG_S_FEATURES_OK on restore
2014-12-18 20:50:30 -08:00
Linus Torvalds 9f3e151299 A balloon enhancement, and a minor race-on-module-unload theoretical
bug which doesn't merit cc: stable.
 
 All the exciting stuff went via MST this cycle.
 
 Thanks,
 Rusty.
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Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull virtio updates from Rusty Russell:
 "A balloon enhancement, and a minor race-on-module-unload theoretical
  bug which doesn't merit cc: stable.

  All the exciting stuff went via MST this cycle"

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  virtio_balloon: free some memory from balloon on OOM
  virtio_balloon: return the amount of freed memory from leak_balloon()
  virtio_blk: fix race at module removal
  virtio: Fix comment typo 'CONFIG_S_FAILED'
2014-12-17 10:37:56 -08:00
Herbert Xu 5ff16110c6 virtio_pci: restore module attributes
When the virtio_pci driver was moved into virtio_pci_legacy.c the module
licence and other attributes went AWOL.  This patch restores them.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-17 00:59:40 +02:00
Linus Torvalds e6b5be2be4 Driver core patches for 3.19-rc1
Here's the set of driver core patches for 3.19-rc1.
 
 They are dominated by the removal of the .owner field in platform
 drivers.  They touch a lot of files, but they are "simple" changes, just
 removing a line in a structure.
 
 Other than that, a few minor driver core and debugfs changes.  There are
 some ath9k patches coming in through this tree that have been acked by
 the wireless maintainers as they relied on the debugfs changes.
 
 Everything has been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core update from Greg KH:
 "Here's the set of driver core patches for 3.19-rc1.

  They are dominated by the removal of the .owner field in platform
  drivers.  They touch a lot of files, but they are "simple" changes,
  just removing a line in a structure.

  Other than that, a few minor driver core and debugfs changes.  There
  are some ath9k patches coming in through this tree that have been
  acked by the wireless maintainers as they relied on the debugfs
  changes.

  Everything has been in linux-next for a while"

* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
  Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
  fs: debugfs: add forward declaration for struct device type
  firmware class: Deletion of an unnecessary check before the function call "vunmap"
  firmware loader: fix hung task warning dump
  devcoredump: provide a one-way disable function
  device: Add dev_<level>_once variants
  ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
  ath: use seq_file api for ath9k debugfs files
  debugfs: add helper function to create device related seq_file
  drivers/base: cacheinfo: remove noisy error boot message
  Revert "core: platform: add warning if driver has no owner"
  drivers: base: support cpu cache information interface to userspace via sysfs
  drivers: base: add cpu_device_create to support per-cpu devices
  topology: replace custom attribute macros with standard DEVICE_ATTR*
  cpumask: factor out show_cpumap into separate helper function
  driver core: Fix unbalanced device reference in drivers_probe
  driver core: fix race with userland in device_add()
  sysfs/kernfs: make read requests on pre-alloc files use the buffer.
  sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
  fs: sysfs: return EGBIG on write if offset is larger than file size
  ...
2014-12-14 16:10:09 -08:00
Michael S. Tsirkin 9a4253db0c virtio_pci: move probe to common file
It turns out this make everything easier.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-14 15:10:30 +02:00
Michael S. Tsirkin de2b48d581 virtio_pci_common.h: drop VIRTIO_PCI_NO_LEGACY
Legacy drivers use virtio_pci_common.h too, we should not
define VIRTIO_PCI_NO_LEGACY there.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-11 20:04:39 +02:00
Michael S. Tsirkin 30683a8cce virtio: set VIRTIO_CONFIG_S_FEATURES_OK on restore
virtio 1.0 devices require that drivers set VIRTIO_CONFIG_S_FEATURES_OK
after finalizing features.
virtio core missed doing this on restore, fix it up.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-11 20:04:38 +02:00
Michael S. Tsirkin 5f4c976089 virtio_pci: rename virtio_pci -> virtio_pci_common
kbuild does not seem to like it when we name source
files same as the module.
Let's rename virtio_pci -> virtio_pci_common,
and get rid of #include-ing c files.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:05 +02:00
Michael S. Tsirkin a90fdce9dc virtio_pci: update file descriptions and copyright
There's been a lot of changes since 2007.
List main authors, add Red Hat copyright.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:05 +02:00
Michael S. Tsirkin 38eb4a29a7 virtio_pci: split out legacy device support
Move everything dealing with legacy devices out to virtio_pci_legacy.c.
Expose common code APIs in virtio_pci.h

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:04 +02:00
Michael S. Tsirkin 6f8f23d63d virtio_pci: setup config vector indirectly
config vector setup is version specific, do it indirectly.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:04 +02:00
Michael S. Tsirkin b09f00bbfe virtio_pci: setup vqs indirectly
VQ setup is mostly version-specific, add another level of indirection to
split the version-independent code out.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:03 +02:00
Michael S. Tsirkin 5386cef200 virtio_pci: delete vqs indirectly
VQ deletion is mostly version-specific, add another level of indirection
to split the version-independent code out.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:02 +02:00
Michael S. Tsirkin f30eaf4a09 virtio_pci: use priv for vq notification
slightly reduce the amount of pointer chasing this needs to do.
More importantly, this will easily generalize to virtio 1.0.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:02 +02:00
Michael S. Tsirkin 3ec7a77bb3 virtio_pci: free up vq->priv
We don't need to go from vq to vq info on
data path, so using direct vq->priv pointer for that
seems like a waste.

Let's build an array of vq infos, then we can use vq->index
for that lookup.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:01 +02:00
Michael S. Tsirkin f913dd4536 virtio_pci: fix coding style for structs
should be

struct foo {
}

not

struct foo
{
}

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:01 +02:00
Michael S. Tsirkin af535722f8 virtio_pci: add isr field
Use isr field instead of direct access to ioaddr.
This way generalizes easily to virtio 1.0.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 21:42:00 +02:00
Michael S. Tsirkin d71a6fc6b9 virtio: drop legacy_only driver flag
legacy_only flag is now unused, drop it from core.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-09 21:42:00 +02:00
Michael S. Tsirkin 63d9f218a3 virtio_balloon: drop legacy_only driver flag
we have blacklisted balloon in core, no need
for a driver flag.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-09 21:41:59 +02:00
Michael S. Tsirkin 5c609a5ef0 virtio: allow finalize_features to fail
This will make it easy for transports to validate features and return
failure.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 16:32:32 +02:00
Michael S. Tsirkin b6098c3042 virtio: add API to detect legacy devices
transports need to be able to detect legacy-only
devices (ATM balloon only) to use legacy path
to drive them.

Add a core API to do just that.
The implementation just blacklists balloon:
not too pretty, but let's not over-engineer.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-09 12:06:33 +02:00
Michael S. Tsirkin 747ae34a6e virtio: make VIRTIO_F_VERSION_1 a transport bit
Activate VIRTIO_F_VERSION_1 automatically unless legacy_only
is set.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 12:06:32 +02:00
Michael S. Tsirkin df1b57fe59 virtio_balloon: add legacy_only flag
We have no plans to support virtio 1.0 in balloon driver.  Add an
explicit flag to mark it legacy only.

This will be used by follow-up patches.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 12:06:32 +02:00
Michael S. Tsirkin b3bb62d119 virtio: add legacy feature table support
virtio-blk has some legacy feature bits that modern drivers
must not negotiate, but are needed for old legacy hosts
(that e.g. don't support virtio-scsi).
Allow a separate legacy feature table for such cases.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-09 12:05:26 +02:00
Michael S. Tsirkin c102659d69 virtio: simplify feature bit handling
Now that we use u64 for bits, we can simply & them together.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-09 12:05:25 +02:00
Michael S. Tsirkin cb3f6d9da4 virtio: set FEATURES_OK
set FEATURES_OK as per virtio 1.0 spec

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-12-09 12:05:25 +02:00