Commit Graph

525 Commits

Author SHA1 Message Date
Krzysztof Kozlowski
fe0580ac5c virtio: pci: constify ioreadX() iomem argument (as in generic implementation)
The ioreadX() helpers have inconsistent interface.  On some architectures
void *__iomem address argument is a pointer to const, on some not.

Implementations of ioreadX() do not modify the memory under the address so
they can be converted to a "const" version for const-safety and
consistency among architectures.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Allen Hubbe <allenbh@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Jon Mason <jdmason@kudzu.us>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200709072837.5869-5-krzk@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-14 19:56:57 -07:00
Linus Torvalds
57b0779392 virtio: fixes, features
IRQ bypass support for vdpa and IFC
 MLX5 vdpa driver
 Endian-ness fixes for virtio drivers
 Misc other fixes
 
 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 updates from Michael Tsirkin:

 - IRQ bypass support for vdpa and IFC

 - MLX5 vdpa driver

 - Endianness fixes for virtio drivers

 - Misc other fixes

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (71 commits)
  vdpa/mlx5: fix up endian-ness for mtu
  vdpa: Fix pointer math bug in vdpasim_get_config()
  vdpa/mlx5: Fix pointer math in mlx5_vdpa_get_config()
  vdpa/mlx5: fix memory allocation failure checks
  vdpa/mlx5: Fix uninitialised variable in core/mr.c
  vdpa_sim: init iommu lock
  virtio_config: fix up warnings on parisc
  vdpa/mlx5: Add VDPA driver for supported mlx5 devices
  vdpa/mlx5: Add shared memory registration code
  vdpa/mlx5: Add support library for mlx5 VDPA implementation
  vdpa/mlx5: Add hardware descriptive header file
  vdpa: Modify get_vq_state() to return error code
  net/vdpa: Use struct for set/get vq state
  vdpa: remove hard coded virtq num
  vdpasim: support batch updating
  vhost-vdpa: support IOTLB batching hints
  vhost-vdpa: support get/set backend features
  vhost: generialize backend features setting/getting
  vhost-vdpa: refine ioctl pre-processing
  vDPA: dont change vq irq after DRIVER_OK
  ...
2020-08-11 14:34:17 -07:00
Liao Pingfang
46af9adefd virtio_pci_modern: Fix the comment of virtio_pci_find_capability()
Fix the comment of virtio_pci_find_capability() by adding missing comment
for the last parameter: bars.

Fixes: 59a5b0f7bf ("virtio-pci: alloc only resources actually used.")
Signed-off-by: Liao Pingfang <liao.pingfang@zte.com.cn>
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Link: https://lore.kernel.org/r/1596455545-43556-1-git-send-email-wang.yi59@zte.com.cn
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-08-05 11:08:42 -04:00
Mao Wenan
481a0d7422 virtio_ring: Avoid loop when vq is broken in virtqueue_poll
The loop may exist if vq->broken is true,
virtqueue_get_buf_ctx_packed or virtqueue_get_buf_ctx_split
will return NULL, so virtnet_poll will reschedule napi to
receive packet, it will lead cpu usage(si) to 100%.

call trace as below:
virtnet_poll
	virtnet_receive
		virtqueue_get_buf_ctx
			virtqueue_get_buf_ctx_packed
			virtqueue_get_buf_ctx_split
	virtqueue_napi_complete
		virtqueue_poll           //return true
		virtqueue_napi_schedule //it will reschedule napi

to fix this, return false if vq is broken in virtqueue_poll.

Signed-off-by: Mao Wenan <wenan.mao@linux.alibaba.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/1596354249-96204-1-git-send-email-wenan.mao@linux.alibaba.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-08-05 11:08:41 -04:00
Michael S. Tsirkin
99e0d0488b virtio_mem: convert to LE accessors
Virtio mem is modern-only. Use LE accessors for config space.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 11:08:41 -04:00
Michael S. Tsirkin
b025584098 virtio_input: convert to LE accessors
Virtio input is modern-only. Use LE accessors for config space.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 11:08:41 -04:00
Michael S. Tsirkin
805769d7c0 virtio_balloon: use LE config space accesses
Balloon is LE, it's cleaner to access it as such directly.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 11:08:41 -04:00
Michael S. Tsirkin
6399167347 virtio_vdpa: legacy features handling
We normally expect vdpa to use the modern interface.
However for consistency, let's use same APIs as vhost
for legacy guests.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 11:08:40 -04:00
Michael S. Tsirkin
8875bbba97 virtio_balloon: fix sparse warning
balloon uses virtio32_to_cpu instead of cpu_to_virtio32
to convert a native endian number to virtio.
No practical difference but makes sparse warn.
Fix it up.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2020-08-05 09:30:19 -04:00
Linus Torvalds
99ea1521a0 Remove uninitialized_var() macro for v5.9-rc1
- Clean up non-trivial uses of uninitialized_var()
 - Update documentation and checkpatch for uninitialized_var() removal
 - Treewide removal of uninitialized_var()
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Merge tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull uninitialized_var() macro removal from Kees Cook:
 "This is long overdue, and has hidden too many bugs over the years. The
  series has several "by hand" fixes, and then a trivial treewide
  replacement.

   - Clean up non-trivial uses of uninitialized_var()

   - Update documentation and checkpatch for uninitialized_var() removal

   - Treewide removal of uninitialized_var()"

* tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  compiler: Remove uninitialized_var() macro
  treewide: Remove uninitialized_var() usage
  checkpatch: Remove awareness of uninitialized_var() macro
  mm/debug_vm_pgtable: Remove uninitialized_var() usage
  f2fs: Eliminate usage of uninitialized_var() macro
  media: sur40: Remove uninitialized_var() usage
  KVM: PPC: Book3S PR: Remove uninitialized_var() usage
  clk: spear: Remove uninitialized_var() usage
  clk: st: Remove uninitialized_var() usage
  spi: davinci: Remove uninitialized_var() usage
  ide: Remove uninitialized_var() usage
  rtlwifi: rtl8192cu: Remove uninitialized_var() usage
  b43: Remove uninitialized_var() usage
  drbd: Remove uninitialized_var() usage
  x86/mm/numa: Remove uninitialized_var() usage
  docs: deprecated.rst: Add uninitialized_var()
2020-08-04 13:49:43 -07:00
Michael S. Tsirkin
24b6842ade virtio: virtio_has_iommu_quirk -> virtio_has_dma_quirk
Now that the corresponding feature bit has been renamed,
rename the quirk too - it's about special ways to
do DMA, not necessarily about the IOMMU.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-03 16:11:42 -04:00
Michael S. Tsirkin
321bd21261 virtio: VIRTIO_F_IOMMU_PLATFORM -> VIRTIO_F_ACCESS_PLATFORM
Rename the bit to match latest virtio spec.
Add a compat macro to avoid breaking existing userspace.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2020-08-03 16:11:42 -04:00
Weilong Chen
a96b0d061d virtio-mem: Fix build error due to improper use 'select'
As noted in:
https://www.kernel.org/doc/Documentation/kbuild/kconfig-language.txt
"select should be used with care. select will force a symbol to a
value without visiting the dependencies."
Config VIRTIO_MEM should not select CONTIG_ALLOC directly.
Otherwise it will cause an error:
https://bugzilla.kernel.org/show_bug.cgi?id=208245

Signed-off-by: Weilong Chen <chenweilong@huawei.com>
Link: https://lore.kernel.org/r/20200619080333.194753-1-chenweilong@huawei.com
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
2020-07-30 11:28:17 -04:00
Michael S. Tsirkin
168c358af2 virtio_balloon: fix up endian-ness for free cmd id
free cmd id is read using virtio endian, spec says all fields
in balloon are LE. Fix it up.

Fixes: 86a559787e ("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT")
Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Wei Wang <wei.w.wang@intel.com>
Acked-by: David Hildenbrand <david@redhat.com>
2020-07-29 13:24:30 -04:00
Alexander Duyck
ca72cc3483 virtio-balloon: Document byte ordering of poison_val
The poison_val field in the virtio_balloon_config is treated as a
little-endian field by the host. Since we are currently only having to deal
with a single byte poison value this isn't a problem, however if the value
should ever expand it would cause byte ordering issues. Document that in
the code so that we know that if the value should ever expand we need to
byte swap the value on big-endian architectures.

Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Link: https://lore.kernel.org/r/20200713203539.17140.71425.stgit@localhost.localdomain
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
2020-07-29 13:24:30 -04:00
Linus Torvalds
23ee3e4e5b pci-v5.8-fixes-2
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Merge tag 'pci-v5.8-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci into master

Pull PCI fixes from Bjorn Helgaas:

 - Reject invalid IRQ 0 command line argument for virtio_mmio because
   IRQ 0 now generates warnings (Bjorn Helgaas)

 - Revert "PCI/PM: Assume ports without DLL Link Active train links in
   100 ms", which broke nouveau (Bjorn Helgaas)

* tag 'pci-v5.8-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  Revert "PCI/PM: Assume ports without DLL Link Active train links in 100 ms"
  virtio-mmio: Reject invalid IRQ 0 command line argument
2020-07-24 18:30:24 -07:00
Bjorn Helgaas
62ca18a089 virtio-mmio: Reject invalid IRQ 0 command line argument
The "virtio_mmio.device=" command line argument allows a user to specify
the size, address, and IRQ of a virtio device.  Previously the only
requirement for the IRQ was that it be an unsigned integer.

Zero is an unsigned integer but an invalid IRQ number, and after
a85a6c86c2 ("driver core: platform: Clarify that IRQ 0 is invalid"),
attempts to use IRQ 0 cause warnings.

If the user specifies IRQ 0, return failure instead of registering a device
with IRQ 0.

Fixes: a85a6c86c2 ("driver core: platform: Clarify that IRQ 0 is invalid")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
2020-07-22 10:31:45 -05:00
Kees Cook
3f649ab728 treewide: Remove uninitialized_var() usage
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.

In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:

git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
	xargs perl -pi -e \
		's/\buninitialized_var\(([^\)]+)\)/\1/g;
		 s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'

drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.

No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
2020-07-16 12:35:15 -07:00
David Hildenbrand
b3562c6087 virtio-mem: add memory via add_memory_driver_managed()
Virtio-mem managed memory is always detected and added by the virtio-mem
driver, never using something like the firmware-provided memory map.
This is the case after an ordinary system reboot, and has to be guaranteed
after kexec. Especially, virtio-mem added memory resources can contain
inaccessible parts ("unblocked memory blocks"), blindly forwarding them
to a kexec kernel is dangerous, as unplugged memory will get accessed
(esp. written).

Let's use the new way of adding special driver-managed memory introduced
in commit 7b7b27214b ("mm/memory_hotplug: introduce
add_memory_driver_managed()").

This will result in no entries in /sys/firmware/memmap ("raw firmware-
provided memory map"), the memory resource will be flagged
IORESOURCE_MEM_DRIVER_MANAGED (esp., kexec_file_load() will not place
kexec images on this memory), and it is exposed as "System RAM
(virtio_mem)" in /proc/iomem, so esp. kexec-tools can properly handle it.

Example /proc/iomem before this change:
  [...]
  140000000-333ffffff : virtio0
    140000000-147ffffff : System RAM
  334000000-533ffffff : virtio1
    338000000-33fffffff : System RAM
    340000000-347ffffff : System RAM
    348000000-34fffffff : System RAM
  [...]

Example /proc/iomem after this change:
  [...]
  140000000-333ffffff : virtio0
    140000000-147ffffff : System RAM (virtio_mem)
  334000000-533ffffff : virtio1
    338000000-33fffffff : System RAM (virtio_mem)
    340000000-347ffffff : System RAM (virtio_mem)
    348000000-34fffffff : System RAM (virtio_mem)
  [...]

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: teawater <teawaterz@linux.alibaba.com>
Fixes: 5f1f79bbc9 ("virtio-mem: Paravirtualized memory hotplug")
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200611093518.5737-1-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
2020-06-22 12:34:21 -04:00
Dan Carpenter
1c3d69ab53 virtio-mem: silence a static checker warning
Smatch complains that "rc" can be uninitialized if we hit the "break;"
statement on the first iteration through the loop.  I suspect that this
can't happen in real life, but returning a zero literal is cleaner and
silence the static checker warning.

Fixes: 5f1f79bbc9 ("virtio-mem: Paravirtualized memory hotplug")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20200610085911.GC5439@mwanda
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-22 12:34:21 -04:00
Masahiro Yamada
a7f7f6248d treewide: replace '---help---' in Kconfig files with 'help'
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-14 01:57:21 +09:00
Michael S. Tsirkin
544fc7dbbf virtio_mem: convert device block size into 64bit
If subblock size is large (e.g. 1G) 32 bit math involving it
can overflow. Rather than try to catch all instances of that,
let's tweak block size to 64 bit.

It ripples through UAPI which is an ABI change, but it's not too late to
make it, and it will allow supporting >4Gbyte blocks while might
become necessary down the road.

Fixes: 5f1f79bbc9 ("virtio-mem: Paravirtualized memory hotplug")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
2020-06-09 06:42:06 -04:00
Michael S. Tsirkin
b3fb6de7c6 virtio-mem: drop unnecessary initialization
rc is initialized to -ENIVAL but that's never used. Drop it.

Fixes: 5f1f79bbc9 ("virtio-mem: Paravirtualized memory hotplug")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
2020-06-08 05:12:52 -04:00
David Hildenbrand
fce8afd76e virtio-mem: Don't rely on implicit compiler padding for requests
The compiler will add padding after the last member, make that explicit.
The size of a request is always 24 bytes. The size of a response always
10 bytes. Add compile-time checks.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: teawater <teawaterz@linux.alibaba.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200515101402.16597-1-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand
72f9525ad7 virtio-mem: Try to unplug the complete online memory block first
Right now, we always try to unplug single subblocks when processing an
online memory block. Let's try to unplug the complete online memory block
first, in case it is fully plugged and the unplug request is large
enough. Fallback to single subblocks in case the memory block cannot get
unplugged as a whole.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-16-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand
8d4edcfe78 virtio-mem: Use -ETXTBSY as error code if the device is busy
Let's be able to distinguish if the device or if memory is busy.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-15-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand
562e08cd24 virtio-mem: Unplug subblocks right-to-left
We unplug blocks right-to-left, let's also unplug subblocks within a block
right-to-left.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-14-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand
3c42e198e6 virtio-mem: Drop manual check for already present memory
Registering our parent resource will fail if any memory is still present
(e.g., because somebody unloaded the driver and tries to reload it). No
need for the manual check.

Move our "unplug all" handling to after registering the resource.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-13-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand
ebf71552bb virtio-mem: Add parent resource for all added "System RAM"
Let's add a parent resource, named after the virtio device (inspired by
drivers/dax/kmem.c). This allows user space to identify which memory
belongs to which virtio-mem device.

With this change and two virtio-mem devices:
	:/# cat /proc/iomem
	00000000-00000fff : Reserved
	00001000-0009fbff : System RAM
	[...]
	140000000-333ffffff : virtio0
	  140000000-147ffffff : System RAM
	  148000000-14fffffff : System RAM
	  150000000-157ffffff : System RAM
	[...]
	334000000-3033ffffff : virtio1
	  338000000-33fffffff : System RAM
	  340000000-347ffffff : System RAM
	  348000000-34fffffff : System RAM
	[...]

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-12-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand
23e77b5dc9 virtio-mem: Better retry handling
Let's start with a retry interval of 5 seconds and double the time until
we reach 5 minutes, in case we keep getting errors. Reset the retry
interval in case we succeeded.

The two main reasons for having to retry are
- The hypervisor is busy and cannot process our request
- We cannot reach the desired requested_size (esp., not enough memory can
  get unplugged because we can't allocate any subblocks).

Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-11-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand
a573238786 virtio-mem: Offline and remove completely unplugged memory blocks
Let's offline+remove memory blocks once all subblocks are unplugged. We
can use the new Linux MM interface for that. As no memory is in use
anymore, this shouldn't take a long time and shouldn't fail. There might
be corner cases where the offlining could still fail (especially, if
another notifier NACKs the offlining request).

Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-10-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand
8e5c921ca0 virtio-mem: Allow to offline partially unplugged memory blocks
Dropping the reference count of PageOffline() pages during MEM_GOING_ONLINE
allows offlining code to skip them. However, we also have to clear
PG_reserved, because PG_reserved pages get detected as unmovable right
away. Take care of restoring the reference count when offlining is
canceled.

Clarify why we don't have to perform any action when unloading the
driver. Also, let's add a warning if anybody is still holding a
reference to unplugged pages when offlining.

Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-8-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand
255f598507 virtio-mem: Paravirtualized memory hotunplug part 2
We also want to unplug online memory (contained in online memory blocks
and, therefore, managed by the buddy), and eventually replug it later.

When requested to unplug memory, we use alloc_contig_range() to allocate
subblocks in online memory blocks (so we are the owner) and send them to
our hypervisor. When requested to plug memory, we can replug such memory
using free_contig_range() after asking our hypervisor.

We also want to mark all allocated pages PG_offline, so nobody will
touch them. To differentiate pages that were never onlined when
onlining the memory block from pages allocated via alloc_contig_range(), we
use PageDirty(). Based on this flag, virtio_mem_fake_online() can either
online the pages for the first time or use free_contig_range().

It is worth noting that there are no guarantees on how much memory can
actually get unplugged again. All device memory might completely be
fragmented with unmovable data, such that no subblock can get unplugged.

We are not touching the ZONE_MOVABLE. If memory is onlined to the
ZONE_MOVABLE, it can only get unplugged after that memory was offlined
manually by user space. In normal operation, virtio-mem memory is
suggested to be onlined to ZONE_NORMAL. In the future, we will try to
make unplug more likely to succeed.

Add a module parameter to control if online memory shall be touched.

As we want to access alloc_contig_range()/free_contig_range() from
kernel module context, export the symbols.

Note: Whenever virtio-mem uses alloc_contig_range(), all affected pages
are on the same node, in the same zone, and contain no holes.

Acked-by: Michal Hocko <mhocko@suse.com> # to export contig range allocator API
Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alexander Potapenko <glider@google.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-6-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand
c627ff5d98 virtio-mem: Paravirtualized memory hotunplug part 1
Unplugging subblocks of memory blocks that are offline is easy. All we
have to do is watch out for concurrent onlining activity.

Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-5-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand
f2af6d3978 virtio-mem: Allow to specify an ACPI PXM as nid
We want to allow to specify (similar as for a DIMM), to which node a
virtio-mem device (and, therefore, its memory) belongs. Add a new
virtio-mem feature flag and export pxm_to_node, so it can be used in kernel
module context.

Acked-by: Michal Hocko <mhocko@suse.com> # for the export
Acked-by: "Rafael J. Wysocki" <rafael@kernel.org> # for the export
Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Len Brown <lenb@kernel.org>
Cc: linux-acpi@vger.kernel.org
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-4-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand
5f1f79bbc9 virtio-mem: Paravirtualized memory hotplug
Each virtio-mem device owns exactly one memory region. It is responsible
for adding/removing memory from that memory region on request.

When the device driver starts up, the requested amount of memory is
queried and then plugged to Linux. On request, further memory can be
plugged or unplugged. This patch only implements the plugging part.

On x86-64, memory can currently be plugged in 4MB ("subblock") granularity.
When required, a new memory block will be added (e.g., usually 128MB on
x86-64) in order to plug more subblocks. Only x86-64 was tested for now.

The online_page callback is used to keep unplugged subblocks offline
when onlining memory - similar to the Hyper-V balloon driver. Unplugged
pages are marked PG_offline, to tell dump tools (e.g., makedumpfile) to
skip them.

User space is usually responsible for onlining the added memory. The
memory hotplug notifier is used to synchronize virtio-mem activity
against memory onlining/offlining.

Each virtio-mem device can belong to a NUMA node, which allows us to
easily add/remove small chunks of memory to/from a specific NUMA node by
using multiple virtio-mem devices. Something that works even when the
guest has no idea about the NUMA topology.

One way to view virtio-mem is as a "resizable DIMM" or a DIMM with many
"sub-DIMMS".

This patch directly introduces the basic infrastructure to implement memory
unplug. Especially the memory block states and subblock bitmaps will be
heavily used there.

Notes:
- In case memory is to be onlined by user space, we limit the amount of
  offline memory blocks, to not run out of memory. This is esp. an
  issue if memory is added faster than it is getting onlined.
- Suspend/Hibernate is not supported due to the way virtio-mem devices
  behave. Limited support might be possible in the future.
- Reloading the device driver is not supported.

Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: linux-acpi@vger.kernel.org
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-2-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
Alexander Duyck
fb69c2c896 virtio-balloon: Disable free page reporting if page poison reporting is not enabled
We should disable free page reporting if page poisoning is enabled but we
cannot report it via the balloon interface. This way we can avoid the
possibility of corrupting guest memory. Normally the page poisoning feature
should always be present when free page reporting is enabled on the
hypervisor, however this allows us to correctly handle a case of the
virtio-balloon device being possibly misconfigured.

Fixes: 5d757c8d518d ("virtio-balloon: add support for providing free page reports to host")
Cc: stable@vger.kernel.org
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Link: https://lore.kernel.org/r/20200508173732.17877.85060.stgit@localhost.localdomain
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:51 -04:00
Markus Elfring
0c35c67412 virtio-mmio: Delete an error message in vm_find_vqs()
The function “platform_get_irq” can log an error already.
Thus omit a redundant message for the exception handling in the
calling function.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Link: https://lore.kernel.org/r/9e27bc4a-cfa1-7818-dc25-8ad308816b30@web.de
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-02 02:45:13 -04:00
Matej Genci
e7c8cc35a6 virtio: add VIRTIO_RING_NO_LEGACY
Add macro to disable legacy vring functions.

Signed-off-by: Matej Genci <matej.genci@nutanix.com>
Link: https://lore.kernel.org/r/20190911124942.243713-1-matej.genci@nutanix.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-02 02:45:13 -04:00
Alexander Duyck
31ba514b2f virtio-balloon: Avoid using the word 'report' when referring to free page hinting
It can be confusing to have multiple features within the same driver that
are using the same verbage. As such this patch is creating a union of
free_page_report_cmd_id with free_page_hint_cmd_id so that we can clean-up
the userspace code a bit in terms of readability while maintaining the
functionality of legacy code.

Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Link: https://lore.kernel.org/r/20200415174318.13597.99753.stgit@localhost.localdomain
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-17 06:05:30 -04:00
Jason Yan
dc39cbb4e8 virtio-balloon: make virtballoon_free_page_report() static
Fix the following sparse warning:

drivers/virtio/virtio_balloon.c:168:5: warning: symbol
'virtballoon_free_page_report' was not declared. Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Link: https://lore.kernel.org/r/20200409085047.45483-1-yanaijie@huawei.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-17 06:05:30 -04:00
Michael S. Tsirkin
58ad13729a vdpa: make vhost, virtio depend on menu
If user did not configure any vdpa drivers, neither vhost
nor virtio vdpa are going to be useful. So there's no point
in prompting for these and selecting vdpa core automatically.
Simplify configuration by making virtio and vhost vdpa
drivers depend on vdpa menu entry. Once done, we no longer
need a separate menu entry, so also get rid of this.
While at it, fix up the IFC entry: VDPA->vDPA for consistency
with other places.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-04-17 06:05:30 -04:00
Michael S. Tsirkin
f091abe806 virtio_input: pull in slab.h
In preparation to virtio header changes, include slab.h directly as
this module is using it.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-17 06:05:29 -04:00
Linus Torvalds
9bb715260e virtio: fixes, vdpa
Some bug fixes.
 The new vdpa subsystem with two first drivers.
 
 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 updates from Michael Tsirkin:

 - Some bug fixes

 - The new vdpa subsystem with two first drivers

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio-balloon: Revert "virtio-balloon: Switch back to OOM handler for VIRTIO_BALLOON_F_DEFLATE_ON_OOM"
  vdpa: move to drivers/vdpa
  virtio: Intel IFC VF driver for VDPA
  vdpasim: vDPA device simulator
  vhost: introduce vDPA-based backend
  virtio: introduce a vDPA based transport
  vDPA: introduce vDPA bus
  vringh: IOTLB support
  vhost: factor out IOTLB
  vhost: allow per device message handler
  vhost: refine vhost and vringh kconfig
  virtio-balloon: Switch back to OOM handler for VIRTIO_BALLOON_F_DEFLATE_ON_OOM
  virtio-net: Introduce hash report feature
  virtio-net: Introduce RSS receive steering feature
  virtio-net: Introduce extended RSC feature
  tools/virtio: option to build an out of tree module
2020-04-08 10:51:53 -07:00
David Hildenbrand
da10329cb0 virtio-balloon: switch back to OOM handler for VIRTIO_BALLOON_F_DEFLATE_ON_OOM
Commit 71994620bb ("virtio_balloon: replace oom notifier with shrinker")
changed the behavior when deflation happens automatically.  Instead of
deflating when called by the OOM handler, the shrinker is used.

However, the balloon is not simply some other slab cache that should be
shrunk when under memory pressure.  The shrinker does not have a concept
of priorities yet, so this behavior cannot be configured.  Eventually once
that is in place, we might want to switch back after doing proper testing.

There was a report that this results in undesired side effects when
inflating the balloon to shrink the page cache. [1]
	"When inflating the balloon against page cache (i.e. no free memory
	 remains) vmscan.c will both shrink page cache, but also invoke the
	 shrinkers -- including the balloon's shrinker. So the balloon
	 driver allocates memory which requires reclaim, vmscan gets this
	 memory by shrinking the balloon, and then the driver adds the
	 memory back to the balloon. Basically a busy no-op."

The name "deflate on OOM" makes it pretty clear when deflation should
happen - after other approaches to reclaim memory failed, not while
reclaiming. This allows to minimize the footprint of a guest - memory
will only be taken out of the balloon when really needed.

Keep using the shrinker for VIRTIO_BALLOON_F_FREE_PAGE_HINT, because
this has no such side effects. Always register the shrinker with
VIRTIO_BALLOON_F_FREE_PAGE_HINT now. We are always allowed to reuse free
pages that are still to be processed by the guest. The hypervisor takes
care of identifying and resolving possible races between processing a
hinting request and the guest reusing a page.

In contrast to pre commit 71994620bb ("virtio_balloon: replace oom
notifier with shrinker"), don't add a module parameter to configure the
number of pages to deflate on OOM. Can be re-added if really needed.
Also, pay attention that leak_balloon() returns the number of 4k pages -
convert it properly in virtio_balloon_oom_notify().

Testing done by Tyler for future reference:
  Test setup: VM with 16 CPU, 64GB RAM. Running Debian 10. We have a 42
  GB file full of random bytes that we continually cat to /dev/null.
  This fills the page cache as the file is read. Meanwhile, we trigger
  the balloon to inflate, with a target size of 53 GB. This setup causes
  the balloon inflation to pressure the page cache as the page cache is
  also trying to grow. Afterwards we shrink the balloon back to zero (so
  total deflate == total inflate).

  Without this patch (kernel 4.19.0-5):
  Inflation never reaches the target until we stop the "cat file >
  /dev/null" process. Total inflation time was 542 seconds. The longest
  period that made no net forward progress was 315 seconds.
    Result of "grep balloon /proc/vmstat" after the test:
    balloon_inflate 154828377
    balloon_deflate 154828377

  With this patch (kernel 5.6.0-rc4+):
  Total inflation duration was 63 seconds. No deflate-queue activity
  occurs when pressuring the page-cache.
    Result of "grep balloon /proc/vmstat" after the test:
    balloon_inflate 12968539
    balloon_deflate 12968539

  Conclusion: This patch fixes the issue.  In the test it reduced
  inflate/deflate activity by 12x, and reduced inflation time by 8.6x.
  But more importantly, if we hadn't killed the "cat file > /dev/null"
  process then, without the patch, the inflation process would never reach
  the target.

[1] https://www.spinics.net/lists/linux-virtualization/msg40863.html

Link: http://lkml.kernel.org/r/20200311135523.18512-2-david@redhat.com
Fixes: 71994620bb ("virtio_balloon: replace oom notifier with shrinker")
Signed-off-by: David Hildenbrand <david@redhat.com>
Reported-by: Tyler Sanderson <tysand@google.com>
Tested-by: Tyler Sanderson <tysand@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Wei Wang <wei.w.wang@intel.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Michal Hocko <mhocko@kernel.org>

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:39 -07:00
Alexander Duyck
b0c504f154 virtio-balloon: add support for providing free page reports to host
Add support for the page reporting feature provided by virtio-balloon.
Reporting differs from the regular balloon functionality in that is is
much less durable than a standard memory balloon.  Instead of creating a
list of pages that cannot be accessed the pages are only inaccessible
while they are being indicated to the virtio interface.  Once the
interface has acknowledged them they are placed back into their respective
free lists and are once again accessible by the guest system.

Unlike a standard balloon we don't inflate and deflate the pages.  Instead
we perform the reporting, and once the reporting is completed it is
assumed that the page has been dropped from the guest and will be faulted
back in the next time the page is accessed.

Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Nitesh Narayan Lal <nitesh@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pankaj Gupta <pagupta@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Wang <wei.w.wang@intel.com>
Cc: Yang Zhang <yang.zhang.wz@gmail.com>
Cc: wei qi <weiqi4@huawei.com>
Link: http://lkml.kernel.org/r/20200211224657.29318.68624.stgit@localhost.localdomain
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:39 -07:00
Alexander Duyck
d74b78fabe virtio-balloon: pull page poisoning config out of free page hinting
Currently the page poisoning setting wasn't being enabled unless free page
hinting was enabled.  However we will need the page poisoning tracking
logic as well for free page reporting.  As such pull it out and make it a
separate bit of config in the probe function.

In addition we need to add support for the more recent init_on_free
feature which expects a behavior similar to page poisoning in that we
expect the page to be pre-zeroed.

Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Nitesh Narayan Lal <nitesh@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pankaj Gupta <pagupta@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Wang <wei.w.wang@intel.com>
Cc: Yang Zhang <yang.zhang.wz@gmail.com>
Cc: wei qi <weiqi4@huawei.com>
Link: http://lkml.kernel.org/r/20200211224646.29318.695.stgit@localhost.localdomain
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:38 -07:00
Michael S. Tsirkin
835a6a649d virtio-balloon: Revert "virtio-balloon: Switch back to OOM handler for VIRTIO_BALLOON_F_DEFLATE_ON_OOM"
This reverts commit 5a6b4cc5b7.

It has been queued properly in the akpm tree, this version is just
creating conflicts.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-07 05:44:57 -04:00
Michael S. Tsirkin
c9b9f5f8c0 vdpa: move to drivers/vdpa
We have both vhost and virtio drivers that depend on vdpa.
It's easier to locate it at a top level directory otherwise
we run into issues e.g. if vhost is built-in but virtio
is modular.  Let's just move it up a level.

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-02 10:41:40 -04:00
Zhu Lingshan
5a2414bc45 virtio: Intel IFC VF driver for VDPA
This commit introduced two layers to drive IFC VF:

(1) ifcvf_base layer, which handles IFC VF NIC hardware operations and
    configurations.

(2) ifcvf_main layer, which complies to VDPA bus framework,
    implemented device operations for VDPA bus, handles device probe,
    bus attaching, vring operations, etc.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Signed-off-by: Bie Tiwei <tiwei.bie@intel.com>
Signed-off-by: Wang Xiao <xiao.w.wang@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200326140125.19794-10-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-02 10:41:40 -04:00