Commit Graph

16 Commits

Author SHA1 Message Date
Linus Torvalds 680b5b3c5d xen: fixes for 5.4-rc3
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Merge tag 'for-linus-5.4-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:

 - correct panic handling when running as a Xen guest

 - cleanup the Xen grant driver to remove printing a pointer being
   always NULL

 - remove a soon to be wrong call of of_dma_configure()

* tag 'for-linus-5.4-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: Stop abusing DT of_dma_configure API
  xen/grant-table: remove unnecessary printing
  x86/xen: Return from panic notifier
2019-10-12 14:11:21 -07:00
Rob Herring ee7f5225dc xen: Stop abusing DT of_dma_configure API
As the removed comments say, these aren't DT based devices.
of_dma_configure() is going to stop allowing a NULL DT node and calling
it will no longer work.

The comment is also now out of date as of commit 9ab91e7c5c ("arm64:
default to the direct mapping in get_arch_dma_ops"). Direct mapping
is now the default rather than dma_dummy_ops.

According to Stefano and Oleksandr, the only other part needed is
setting the DMA masks and there's no reason to restrict the masks to
32-bits. So set the masks to 64 bits.

Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Julien Grall <julien.grall@arm.com>
Cc: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: xen-devel@lists.xenproject.org
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2019-10-10 11:43:35 -04:00
Sam Ravnborg 2ea2269e29 drm/xen: drop use of drmP.h
The drmP.h header is deprecated.  Drop all uses.
Added includes/forwards to the header files and
then fixed fallout in the .c files.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Acked-by: Emil Velikov <emil.velikov@collabora.com>
Cc: xen-devel@lists.xenproject.org
Link: https://patchwork.freedesktop.org/patch/msgid/20190630061922.7254-3-sam@ravnborg.org
2019-07-15 18:11:30 +02:00
Daniel Vetter f30dec2f82 drm/xen: Drop drm_gem_prime_export/import
They're the default.

Aside: Would be really nice to switch the others over to
drm_gem_object_funcs.

Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Cc: xen-devel@lists.xenproject.org
Link: https://patchwork.freedesktop.org/patch/msgid/20190614203615.12639-39-daniel.vetter@ffwll.ch
2019-06-21 20:12:05 +02:00
Daniel Vetter 0424fdaf88 drm/prime: Actually remove DRIVER_PRIME everywhere
Split out to make the functional changes stick out more.

All places where DRIVER_PRIME was used have been removed in previous
patches already.

v2: amdgpu gained DRIVER_SYNCOBJ_TIMELINE.

v3: amdgpu lost DRIVER_SYNCOBJ_TIMELINE.

v4: Don't add a space in i915_drv.c (Sam)

v5: Add note that previous patches removed all the DRIVER_PRIME users
already (Emil).

v6: Fixupe ingenic (new driver) while applying.

Cc: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: amd-gfx@lists.freedesktop.org
Cc: etnaviv@lists.freedesktop.org
Cc: freedreno@lists.freedesktop.org
Cc: intel-gfx@lists.freedesktop.org
Cc: lima@lists.freedesktop.org
Cc: linux-amlogic@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-arm-msm@vger.kernel.org
Cc: linux-aspeed@lists.ozlabs.org
Cc: linux-renesas-soc@vger.kernel.org
Cc: linux-rockchip@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-stm32@st-md-mailman.stormreply.com
Cc: linux-tegra@vger.kernel.org
Cc: nouveau@lists.freedesktop.org
Cc: NXP Linux Team <linux-imx@nxp.com>
Cc: spice-devel@lists.freedesktop.org
Cc: virtualization@lists.linux-foundation.org
Cc: VMware Graphics <linux-graphics-maintainer@vmware.com>
Cc: xen-devel@lists.xenproject.org
Link: https://patchwork.freedesktop.org/patch/msgid/20190617153924.414-1-daniel.vetter@ffwll.ch
2019-06-21 17:30:32 +02:00
Noralf Trønnes ba3bf37e15 drm/drv: drm_dev_unplug(): Move out drm_dev_put() call
This makes it possible to use drm_dev_unplug() with the upcoming
devm_drm_dev_init() which will do drm_dev_put() in its release callback.

Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: David (ChunMing) Zhou <David1.Zhou@amd.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Sean Paul <sean@poorly.run>
Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190208140103.28919-3-noralf@tronnes.org
2019-02-21 12:11:58 +01:00
Daniel Vetter fcd70cd36b drm: Split out drm_probe_helper.h
Having the probe helper stuff (which pretty much everyone needs) in
the drm_crtc_helper.h file (which atomic drivers should never need) is
confusing. Split them out.

To make sure I actually achieved the goal here I went through all
drivers. And indeed, all atomic drivers are now free of
drm_crtc_helper.h includes.

v2: Make it compile. There was so much compile fail on arm drivers
that I figured I'll better not include any of the acks on v1.

v3: Massive rebase because i915 has lost a lot of drmP.h includes, but
not all: Through drm_crtc_helper.h > drm_modeset_helper.h -> drmP.h
there was still one, which this patch largely removes. Which means
rolling out lots more includes all over.

This will also conflict with ongoing drmP.h cleanup by others I
expect.

v3: Rebase on top of atomic bochs.

v4: Review from Laurent for bridge/rcar/omap/shmob/core bits:
- (re)move some of the added includes, use the better include files in
  other places (all suggested from Laurent adopted unchanged).
- sort alphabetically

v5: Actually try to sort them, and while at it, sort all the ones I
touch.

v6: Rebase onto i915 changes.

v7: Rebase once more.

Acked-by: Harry Wentland <harry.wentland@amd.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Acked-by: CK Hu <ck.hu@mediatek.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: virtualization@lists.linux-foundation.org
Cc: etnaviv@lists.freedesktop.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-amlogic@lists.infradead.org
Cc: linux-arm-msm@vger.kernel.org
Cc: freedreno@lists.freedesktop.org
Cc: nouveau@lists.freedesktop.org
Cc: spice-devel@lists.freedesktop.org
Cc: amd-gfx@lists.freedesktop.org
Cc: linux-renesas-soc@vger.kernel.org
Cc: linux-rockchip@lists.infradead.org
Cc: linux-stm32@st-md-mailman.stormreply.com
Cc: linux-tegra@vger.kernel.org
Cc: xen-devel@lists.xen.org
Link: https://patchwork.freedesktop.org/patch/msgid/20190117210334.13234-1-daniel.vetter@ffwll.ch
2019-01-24 13:20:42 +01:00
Oleksandr Andrushchenko 5641f19bdf drm/xen-front: Use Xen common shared buffer implementation
Use page directory based shared buffer implementation
now available as common code for Xen frontend drivers.

Remove flushing of shared buffer on page flip as this
workaround needs a proper fix.

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2018-12-18 12:16:13 -05:00
Dave Airlie f4366e44ef drm-misc-next for 4.19:
Cross-subsystem Changes:
 - fix compile breakage on ION due to the dma-buf cleanups (Christian König)
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Merge tag 'drm-misc-next-2018-06-21' of git://anongit.freedesktop.org/drm/drm-misc into drm-next

drm-misc-next for 4.19:

UAPI Changes:
- Add writeback connector (Brian Starkey/Liviu Dudau)
- Add "content type" property to HDMI connectors (Stanislav Lisovskiy)

Cross-subsystem Changes:
- some devicetree Docs update
- fix compile breakage on ION due to the dma-buf cleanups (Christian König)

Core Changes:
- Reject over-sized allocation requests early (Chris Wilson)
- gem-fb-helper: Always do implicit sync (Daniel Vetter)
- dma-buf cleanups (Christian König)

Driver Changes:
- Fixes for the otm8009a panel driver (Philippe Cornu)
- Add Innolux TV123WAM panel driver support (Sandeep Panda)
- Move GEM BO to drm_framebuffer in few drivers (Daniel Stone)
- i915 pinning improvements (Chris Wilson)
- Stop consulting plane->fb/crtc in a few drivers (Ville Syrjälä)

Signed-off-by: Dave Airlie <airlied@redhat.com>

Link: https://patchwork.freedesktop.org/patch/msgid/20180621105428.GA20795@juma
2018-06-22 12:58:08 +10:00
Linus Torvalds 135c5504a6 drm for v4.18-rc1
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Merge tag 'drm-next-2018-06-06-1' of git://anongit.freedesktop.org/drm/drm

Pull drm updates from Dave Airlie:
 "This starts to support NVIDIA volta hardware with nouveau, and adds
  amdgpu support for the GPU in the Kabylake-G (the intel + radeon
  single package chip), along with some initial Intel icelake enabling.

  Summary:

  New Drivers:
   - v3d - driver for broadcom V3D V3.x+ hardware
   - xen-front - XEN PV display frontend

  core:
   - handle zpos normalization in the core
   - stop looking at legacy pointers in atomic paths
   - improved scheduler documentation
   - improved aspect ratio validation
   - aspect ratio support for 64:27 and 256:135
   - drop unused control node code.

  i915:
   - Icelake (ICL) enabling
   - GuC/HuC refactoring
   - PSR/PSR2 enabling and fixes
   - DPLL management refactoring
   - DP MST fixes
   - NV12 enabling
   - HDCP improvements
   - GEM/Execlist/reset improvements
   - GVT improvements
   - stolen memory first 4k fix

  amdgpu:
   - Vega 20 support
   - VEGAM support (Kabylake-G)
   - preOS scanout buffer reservation
   - power management gfxoff support for raven
   - SR-IOV fixes
   - Vega10 power profiles and clock voltage control
   - scatter/gather display support on CZ/ST

  amdkfd:
   - GFX9 dGPU support
   - userptr memory mapping

  nouveau:
   - major refactoring for Volta GV100 support

  tda998x:
   - HDMI i2c CEC support

  etnaviv:
   - removed unused logging code
   - license text cleanups
   - MMU handling improvements
   - timeout fence fix for 50 days uptime

  tegra:
   - IOMMU support in gr2d/gr3d drivers
   - zpos support

  vc4:
   - syncobj support
   - CTM, plane alpha and async cursor support

  analogix_dp:
   - HPD and aux chan fixes

  sun4i:
   - MIPI DSI support

  tilcdc:
   - clock divider fixes for OMAP-l138 LCDK board

  rcar-du:
   - R8A77965 support
   - dma-buf fences fixes
   - hardware indexed crtc/du group handling
   - generic zplane property support

  atmel-hclcdc:
   - generic zplane property support

  mediatek:
   - use generic video mode function

  exynos:
   - S5PV210 FIMD variant support
   - IPP v2 framework
   - more HW overlays support"

* tag 'drm-next-2018-06-06-1' of git://anongit.freedesktop.org/drm/drm: (1286 commits)
  drm/amdgpu: fix 32-bit build warning
  drm/exynos: fimc: signedness bug in fimc_setup_clocks()
  drm/exynos: scaler: fix static checker warning
  drm/amdgpu: Use dev_info() to report amdkfd is not supported for this ASIC
  drm/amd/display: Remove use of division operator for long longs
  drm/amdgpu: Update GFX info structure to match what vega20 used
  drm/amdgpu/pp: remove duplicate assignment
  drm/sched: add rcu_barrier after entity fini
  drm/amdgpu: move VM BOs on LRU again
  drm/amdgpu: consistenly use VM moved flag
  drm/amdgpu: kmap PDs/PTs in amdgpu_vm_update_directories
  drm/amdgpu: further optimize amdgpu_vm_handle_moved
  drm/amdgpu: cleanup amdgpu_vm_validate_pt_bos v2
  drm/amdgpu: rework VM state machine lock handling v2
  drm/amdgpu: Add runtime VCN PG support
  drm/amdgpu: Enable VCN static PG by default on RV
  drm/amdgpu: Add VCN static PG support on RV
  drm/amdgpu: Enable VCN CG by default on RV
  drm/amdgpu: Add static CG control for VCN on RV
  drm/exynos: Fix default value for zpos plane property
  ...
2018-06-06 08:16:33 -07:00
Colin Ian King aefff49156 drm/xen-front: fix spelling mistake: "conector" -> "connector"
Trivial fix to spelling mistake in DRM_INFO message.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180515085433.8245-1-colin.king@canonical.com
2018-05-15 12:13:51 +03:00
Dan Carpenter f45140df31 drm/xen-front: Fix loop timeout
If the loop times out then we want to exit with "to" set to zero, but in
the current code it's set to -1.

Fixes: c575b7eeb8 ("drm/xen-front: Add support for Xen PV display frontend")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180508092829.GC661@mwanda
2018-05-08 14:10:01 +03:00
Dan Carpenter 18f20bc530 drm/xen-front: fix xen_drm_front_shbuf_alloc() error handling
The xen_drm_front_shbuf_alloc() function was returning a mix of error
pointers and NULL and the the caller wasn't checking correctly.  I've
changed it to always return error pointer consistently.

Fixes: c575b7eeb8 ("drm/xen-front: Add support for Xen PV display frontend")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180508092739.GB661@mwanda
2018-05-08 14:09:52 +03:00
Dan Carpenter e30ca4bcf0 drm/xen-front: checking for NULL instead of IS_ERR
drm_dev_alloc() returns error pointers, it never returns NULL.

Fixes: c575b7eeb8 ("drm/xen-front: Add support for Xen PV display frontend")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180508092650.GA661@mwanda
2018-05-08 14:09:40 +03:00
Oleksandr Andrushchenko 4394e96423 drm/xen-front: Remove CMA support
It turns out this was only needed to paper over a bug in the CMA
helpers, which was addressed in

commit 998fb1a0f4
Author: Liviu Dudau <Liviu.Dudau@arm.com>
Date:   Fri Nov 10 13:33:10 2017 +0000

    drm: gem_cma_helper.c: Allow importing of contiguous scatterlists with nents > 1

Without this the following pipeline didn't work:

domU:
1. xen-front allocates a non-contig buffer
2. creates grants out of it

dom0:
3. converts the grants into a dma-buf. Since they're non-contig, the
scatter-list is huge.
4. imports it into rcar-du, which requires dma-contig memory for
scanout.

-> On this given platform there's an IOMMU, so in theory this should
work. But in practice this failed, because of the huge number of sg
entries, even though the IOMMU driver mapped it all into a dma-contig
range.

With a guest-contig buffer allocated in step 1, this problem doesn't
exist. But there's technically no reason to require guest-contig
memory for xen buffer sharing using grants.

Given all that, the xen-front cma support is not needed and should be
removed.

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180417074012.21311-1-andr2000@gmail.com
2018-04-18 10:18:27 +03:00
Oleksandr Andrushchenko c575b7eeb8 drm/xen-front: Add support for Xen PV display frontend
Add support for Xen para-virtualized frontend display driver.
Accompanying backend [1] is implemented as a user-space application
and its helper library [2], capable of running as a Weston client
or DRM master.
Configuration of both backend and frontend is done via
Xen guest domain configuration options [3].

Driver limitations:
 1. Only primary plane without additional properties is supported.
 2. Only one video mode supported which resolution is configured
    via XenStore.
 3. All CRTCs operate at fixed frequency of 60Hz.

1. Implement Xen bus state machine for the frontend driver according to
the state diagram and recovery flow from display para-virtualized
protocol: xen/interface/io/displif.h.

2. Read configuration values from Xen store according
to xen/interface/io/displif.h protocol:
  - read connector(s) configuration
  - read buffer allocation mode (backend/frontend)

3. Handle Xen event channels:
  - create for all configured connectors and publish
    corresponding ring references and event channels in Xen store,
    so backend can connect
  - implement event channels interrupt handlers
  - create and destroy event channels with respect to Xen bus state

4. Implement shared buffer handling according to the
para-virtualized display device protocol at xen/interface/io/displif.h:
  - handle page directories according to displif protocol:
    - allocate and share page directories
    - grant references to the required set of pages for the
      page directory
  - allocate xen balllooned pages via Xen balloon driver
    with alloc_xenballooned_pages/free_xenballooned_pages
  - grant references to the required set of pages for the
    shared buffer itself
  - implement pages map/unmap for the buffers allocated by the
    backend (gnttab_map_refs/gnttab_unmap_refs)

5. Implement kernel modesetiing/connector handling using
DRM simple KMS helper pipeline:

- implement KMS part of the driver with the help of DRM
  simple pipepline helper which is possible due to the fact
  that the para-virtualized driver only supports a single
  (primary) plane:
  - initialize connectors according to XenStore configuration
  - handle frame done events from the backend
  - create and destroy frame buffers and propagate those
    to the backend
  - propagate set/reset mode configuration to the backend on display
    enable/disable callbacks
  - send page flip request to the backend and implement logic for
    reporting backend IO errors on prepare fb callback

- implement virtual connector handling:
  - support only pixel formats suitable for single plane modes
  - make sure the connector is always connected
  - support a single video mode as per para-virtualized driver
    configuration

6. Implement GEM handling depending on driver mode of operation:
depending on the requirements for the para-virtualized environment,
namely requirements dictated by the accompanying DRM/(v)GPU drivers
running in both host and guest environments, number of operating
modes of para-virtualized display driver are supported:
 - display buffers can be allocated by either
   frontend driver or backend
 - display buffers can be allocated to be contiguous
   in memory or not

Note! Frontend driver itself has no dependency on contiguous memory for
its operation.

6.1. Buffers allocated by the frontend driver.

The below modes of operation are configured at compile-time via
frontend driver's kernel configuration.

6.1.1. Front driver configured to use GEM CMA helpers
     This use-case is useful when used with accompanying DRM/vGPU driver
     in guest domain which was designed to only work with contiguous
     buffers, e.g. DRM driver based on GEM CMA helpers: such drivers can
     only import contiguous PRIME buffers, thus requiring frontend driver
     to provide such. In order to implement this mode of operation
     para-virtualized frontend driver can be configured to use
     GEM CMA helpers.

6.1.2. Front driver doesn't use GEM CMA
     If accompanying drivers can cope with non-contiguous memory then, to
     lower pressure on CMA subsystem of the kernel, driver can allocate
     buffers from system memory.

Note! If used with accompanying DRM/(v)GPU drivers this mode of operation
may require IOMMU support on the platform, so accompanying DRM/vGPU
hardware can still reach display buffer memory while importing PRIME
buffers from the frontend driver.

6.2. Buffers allocated by the backend

This mode of operation is run-time configured via guest domain
configuration through XenStore entries.

For systems which do not provide IOMMU support, but having specific
requirements for display buffers it is possible to allocate such buffers
at backend side and share those with the frontend.
For example, if host domain is 1:1 mapped and has DRM/GPU hardware
expecting physically contiguous memory, this allows implementing
zero-copying use-cases.

Note, while using this scenario the following should be considered:
  a) If guest domain dies then pages/grants received from the backend
     cannot be claimed back
  b) Misbehaving guest may send too many requests to the
     backend exhausting its grant references and memory
     (consider this from security POV).

Note! Configuration options 1.1 (contiguous display buffers) and 2
(backend allocated buffers) are not supported at the same time.

7. Handle communication with the backend:
 - send requests and wait for the responses according
   to the displif protocol
 - serialize access to the communication channel
 - time-out used for backend communication is set to 3000 ms
 - manage display buffers shared with the backend

[1] https://github.com/xen-troops/displ_be
[2] https://github.com/xen-troops/libxenbe
[3] https://xenbits.xen.org/gitweb/?p=xen.git;a=blob;f=docs/man/xl.cfg.pod.5.in;h=a699367779e2ae1212ff8f638eff0206ec1a1cc9;hb=refs/heads/master#l1257

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180403112317.28751-2-andr2000@gmail.com
2018-04-03 14:41:48 +03:00