This helps initramfs builder and other tools to know the full dependencies
of i915 and have gvt module loaded with i915.
v2: add condition and change to pre-dependency (Chris)
v3: move declaration to gvt.c. (Chris)
v4: remove xengt (Zhenyu)
Signed-off-by: Hang Yuan <hang.yuan@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Initialize BXT device info as SKL/KBL.
v2: All supported platforms share the same device configuration.
Remove the platform check by now and let is_supported_device()
be the gate keeper.
Signed-off-by: Colin Xu <colin.xu@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
The scheduler lock(gvt->sched_lock) is used to protect gvt
scheduler logic, including the gvt scheduler structure(gvt->scheduler
and per vgpu schedule data(vgpu->sched_data, vgpu->sched_ctl).
v9:
- Change commit author since the patches are improved a lot compared
with original version.
Original author: Pei Zhang <pei.zhang@intel.com>
- Rebase to latest gvt-staging.
v8:
- Correct coding wqstyle.
- Rebase to latest gvt-staging.
v7:
- Remove gtt_lock since already proteced by gvt_lock and vgpu_lock.
v6:
- Rebase to latest gvt-staging.
v5:
- Rebase to latest gvt-staging.
v4:
- Rebase to latest gvt-staging.
v3: update to latest code base
Signed-off-by: Pei Zhang <pei.zhang@intel.com>
Signed-off-by: Colin Xu <colin.xu@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch provide generic page_track infrastructure for write-protected
guest page. The old page_track logic gets rewrote and now stays in a new
standalone page_track.c. This page track infrastructure can be both used
by vGUC and GTT shadowing.
The important change is that it uses radix tree instead of hash table.
We don't have a predictable number of pages that will be tracked.
Here is some performance data (duration in us) of looking up a element:
Before: (aka. intel_vgpu_find_tracked_page)
0.091 0.089 0.090 ... 0.093 0.091 0.087 ... 0.292 0.285 0.292 0.291
After: (aka. intel_vgpu_find_page_track)
0.104 0.105 0.100 0.102 0.102 0.100 ... 0.101 0.101 0.105 0.105
The hash table has good performance at beginning, but turns bad with
more pages being tracked even no 3D applications are running. As
expected, radix tree has stable duration and very quick.
The overall benchmark (tested with Heaven Benchmark) marginally improved
since this is not the bottleneck. What we benefit more from this change
is scalability.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
It's a bit confusing that page write protect handler is live in
mmio emulation handler. This moves it to stand alone gvt ops.
Also remove unnecessary check of write protected page access
in mmio read handler and cleanup handling of failsafe case.
v2: rebase
Reviewed-by: Xiong Zhang <xiong.y.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Select appropriate mmio list at initialization time, so we don't need to
do duplicated work at where requires the mmio list.
V2:
- Add a termination mark of mmio list.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces a guest's framebuffer sharing mechanism based on
dma-buf subsystem. With this sharing mechanism, guest's framebuffer can
be shared between guest VM and host.
v17:
- modify VFIO_DEVICE_GET_GFX_DMABUF interface. (Alex)
v16:
- add x_hot and y_hot. (Gerd)
- add flag validation for VFIO_DEVICE_GET_GFX_DMABUF. (Alex)
- rebase 4.14.0-rc6.
v15:
- add VFIO_DEVICE_GET_GFX_DMABUF ABI. (Gerd)
- add intel_vgpu_dmabuf_cleanup() to clean up the vGPU's dmabuf. (Gerd)
v14:
- add PROBE, DMABUF and REGION flags. (Alex)
v12:
- refine the lifecycle of dmabuf.
v9:
- remove dma-buf management. (Alex)
- track the dma-buf create and release in kernel mode. (Gerd) (Daniel)
v8:
- refine the dma-buf ioctl definition.(Alex)
- add a lock to protect the dmabuf list. (Alex)
v7:
- release dma-buf related allocations in dma-buf's associated release
function. (Alex)
- refine ioctl interface for querying plane info or create dma-buf.
(Alex)
v6:
- align the dma-buf life cycle with the vfio device. (Alex)
- add the dma-buf related operations in a separate patch. (Gerd)
- i915 related changes. (Chris)
v5:
- fix bug while checking whether the gem obj is gvt's dma-buf when user
change caching mode or domains. Add a helper function to do it.
(Xiaoguang)
- add definition for the query plane and create dma-buf. (Xiaoguang)
v4:
- fix bug while checking whether the gem obj is gvt's dma-buf when set
caching mode or doamins. (Xiaoguang)
v3:
- declare a new flag I915_GEM_OBJECT_IS_GVT_DMABUF in drm_i915_gem_object
to represent the gem obj for gvt's dma-buf. The tiling mode, caching
mode and domains can not be changed for this kind of gem object. (Alex)
- change dma-buf related information to be more generic. So other vendor
can use the same interface. (Alex)
v2:
- create a management fd for dma-buf operations. (Alex)
- alloc gem object's backing storage in gem obj's get_pages() callback.
(Chris)
Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Currently every vgpu share a common gvt opregion memory, but
it is freed at vgpu destroy, then the later vgpu doesn't have
opregion memory once the first vgpu is destroyed. This cause
guest function failure like reboot, second or later boot.
This patch allocate and init virt opregion memory for each
vgpu, so this memory could be freed at vgpu destroy.
Signed-off-by: Xiong Zhang <xiong.y.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
We need debugfs entry to expose some debug information of gvt and vGPUs.
The first tool will be added is mmio-diff, which help to find the
difference values of host and vGPU mmio. It's useful for platform
enabling.
This patch just add a basic debugfs infrastructure, each vGPU has its own
sub-folder. Two simple attributes are created as a template.
.
├── num_tracked_mmio
├── vgpu1
| └── active
└── vgpu2
└── active
Signed-off-by: Changbin Du <changbin.du@intel.com>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
In this patch, all the vGPU type related code will be merged into
same gvt file and the common interface will be exposed to both
XenGT and KvmGT.
v2:
- remove the useless mdev_* gvt_ops.
add get_gvt_attr ops for MPT module.
intel_gvt_{init,cleanup}_vgpu_type_groups are initialized in
gvt part. (Wang, Zhi)
- set gvt_vgpu_type_groups[i] to NULL. (Zhang,Xiong)
Signed-off-by: fred gao <fred.gao@intel.com>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
This patch decouple the time slice calculation and scheduler, let
other event be able to trigger scheduling without impact the
calculation for QoS.
v2: add only one new enum definition.
v3: fix typo.
Signed-off-by: Ping Gao <ping.a.gao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Commit ab9da627906a ("drm/i915: make context status notifier head be
per engine") gives us a chance to inspect every single request. Then
we can eliminate unnecessary mmio switching for same vGPU. We only
need mmio switching for different VMs (including host).
This patch introduced a new general API intel_gvt_switch_mmio() to
replace the old intel_gvt_load/restore_render_mmio(). This function
can be further optimized for vGPU to vGPU switching.
To support individual ring switch, we track the owner who occupy
each ring. When another VM or host request a ring we do the mmio
context switching. Otherwise no need to switch the ring.
This optimization is very useful if only one guest has plenty of
workloads and the host is mostly idle. The best case is no mmio
switching will happen.
v2:
o fix missing ring switch issue. (chuanxiao)
o support individual ring switch.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Reviewed-by: Chuanxiao Dong <chuanxiao.dong@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
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Merge tag 'v4.11-rc7' into drm-next
Backmerge Linux 4.11-rc7 from Linus tree, to fix some
conflicts that were causing problems with the rerere cache
in drm-tip.
This patch introduces two functions for activating/de-activating vGPU in
mdev ops.
A racing condition was found between virtual vblank emulation and KVGMT
mdev release path. V-blank emulation will emulate and inject V-blank
interrupt for every active vGPU with holding gvt->lock, while in mdev
release path, it will directly release hypervisor handle without changing
vGPU status or taking gvt->lock, so a kernel oops is encountered when
vblank emulation is injecting a interrupt with a invalid hypervisor
handle. (Reported by Terrence)
To solve this problem, we factor out vGPU activation/de-activation from
vGPU creation/destruction path and let KVMGT mdev release ops de-activate
the vGPU before release hypervisor handle. Once a vGPU is de-activated,
GVT-g will not emulate v-blank for it or touch the hypervisor handle.
Fixes: 659643f ("drm/i915/gvt/kvmgt: add vfio/mdev support to KVMGT")
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
vGPU resource is allocated by scheduler. To account for non-allocated
free cycles, we create an idle vGPU as the placeholder similar to idle task
concept, which is useful to handle some corner cases in scheduling policy.
Signed-off-by: Ping Gao <ping.a.gao@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Currently the scheduler is triggered by delayed_work, which doesn't
provide precision at microsecond level. Move to hrtimer instead for
more accurate control.
Signed-off-by: Ping Gao <ping.a.gao@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
gvt driver has a check which doesn't allow to use gvt when host
gpu iommu is enabled. This check can be removed after enable the
iommu support in gvt
Signed-off-by: Chuanxiao Dong <chuanxiao.dong@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
We only depend on pvinfo register for GVT-g state detection,
not require hypervisor host detect any more.
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
An idr should be initialized before use and destroyed afterwards.
Signed-off-by: Jike Song <jike.song@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
KVMGT is the MPT implementation based on VFIO/KVM. It provides
a kvmgt_mpt ops to gvt for vGPU access mediation, e.g. to
mediate and emulate the MMIO accesses, to inject interrupts
to vGPU user, to intercept the GTT writing and replace it with
DMA-able address, to write-protect guest PPGTT table for
shadowing synchronization, etc. This patch provides the MPT
implementation for GVT, not yet functional due to theabsence
of mdev.
It's built as kvmgt.ko, depends on vfio.ko, kvm.ko and mdev.ko,
and being required by i915.ko. To not introduce hard dependency
in i915.ko, we used indirect symbol reference. But that means
users have to include kvmgt.ko into init ramdisk if their
i915.ko is included.
Signed-off-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Xiaoguang Chen <xiaoguang.chen@intel.com>
Signed-off-by: Jike Song <jike.song@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
There are currently 4 methods in intel_gvt_io_emulation_ops
to emulate CFG/MMIO reading/writing for intel vGPU. A possibly
better scope is: add 3 more methods for vgpu create/destroy/reset
respectively, and rename the ops to 'intel_gvt_ops', then pass
it to the MPT module (say the future kvmgt) to use: they are
all methods for external usage.
Signed-off-by: Jike Song <jike.song@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
GVT host needs init/exit hooks to do some initialization/cleanup
work, e.g.: vfio mdev host device register/unregister.
Signed-off-by: Jike Song <jike.song@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
By providing predefined vGPU types, users can choose which type a vgpu
to create and use, without specifying detailed parameters.
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Jike Song <jike.song@intel.com>
Like other routines, intel_gvt_hypervisor_detect_host returns 0
for success.
Signed-off-by: Xiaoguang Chen <xiaoguang.chen@intel.com>
Signed-off-by: Jike Song <jike.song@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Linux PCI driver saves the msi and msix capability offset
in pci_dev->msi_cap and pci_dev->msix_cap. We can use msi_cap
in pci_dev directly, no need hardcode.
Signed-off-by: Du, Changbin <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
i915 core should only call functions and structures exposed through
intel_gvt.h. Remove internal gvt.h and i915_pvinfo.h.
Change for internal intel_gvt structure as private handler which
not requires to expose gvt internal structure for i915 core.
v2: Fix per Chris's comment
- carefully handle dev_priv->gvt assignment
- add necessary bracket for macro helper
- forward declartion struct intel_gvt
- keep free operation within same file handling alloc
v3: fix use after free and remove intel_gvt.initialized
v4: change to_gvt() to an inline
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces a command scanner to scan guest command buffers.
Signed-off-by: Yulei Zhang <yulei.zhang@intel.com>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces a vGPU schedule policy framework, with a timer based
schedule policy module for now
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces the vGPU workload scheduler routines.
GVT workload scheduler is responsible for picking and executing GVT workload
from current scheduled vGPU. Before the workload is submitted to host i915,
the guest execlist context will be shadowed in the host GVT shadow context.
the instructions in guest ring buffer will be copied into GVT shadow ring
buffer. Then GVT-g workload scheduler will scan the instructions in guest
ring buffer and submit it to host i915.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces the GVT-g display virtualization.
It consists a collection of display MMIO handlers, like power well register
handler, pipe register handler, plane register handler, which will emulate
all display MMIOs behavior to support virtual mode setting sequence for
guest.
Signed-off-by: Bing Niu <bing.niu@intel.com>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces the generic vGPU MMIO emulation intercept
framework. The MPT modules will request GVT-g core logic to
emulate MMIO read/write through IO emulation operations
callback when hypervisor trapped a guest GTTMMIO read/write.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces vGPU PCI configuration space virtualization.
- Adjust the trapped GPFN(Guest Page Frame Number) window of virtual GEN
PCI BAR 0 when guest initializes PCI BAR 0 address.
- Emulate OpRegion when guest touches OpRegion.
- Pass-through a part of aperture to guest when guest initializes
aperture BAR.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
The vGPU graphics memory emulation framework is responsible for graphics
memory table virtualization. Under virtualization environment, a VM will
populate the page table entry with guest page frame number(GPFN/GFN), while
HW needs a page table filled with MFN(Machine frame number). The
relationship between GFN and MFN(Machine frame number) is managed by
hypervisor, while GEN HW doesn't have such knowledge to translate a GFN.
To solve this gap, shadow GGTT/PPGTT page table is introdcued.
For GGTT, the GFN inside the guest GGTT page table entry will be translated
into MFN and written into physical GTT MMIO registers when guest write
virtual GTT MMIO registers.
For PPGTT, a shadow PPGTT page table will be created and write-protected
translated from guest PPGTT page table. And the shadow page table root
pointers will be written into the shadow context after a guest workload
is shadowed.
vGPU graphics memory emulation framework consists:
- Per-GEN HW platform page table entry bits extract/de-extract routines.
- GTT MMIO register emulation handlers, which will call hypercall to do
GFN->MFN translation when guest write GTT MMIO register
- PPGTT shadow page table routines, e.g. shadow create/destroy/out-of-sync
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces vGPU interrupt emulation framework.
The vGPU intrerrupt emulation framework is an event-based interrupt
emulation framework. It's responsible for emulating GEN hardware interrupts
during emulating other HW behaviour.
It consists several components:
- Descriptions of interrupt register bit
- Upper level <-> lower level interrupt mapping
- GEN HW IER/IMR/IIR register emulation routines
- Event-based interrupt propagation interface
When a GVT-g component wants to inject an interrupt to a VM during a
emulation, first it should specify the event needs to be emulated and the
framework will deal with the rest of emulation:
- Generating related virtual IIR bit according to virtual IER and IMRs,
- Generate related virtual upper level virtual IIR bit accodring to the
per-platform interrupt mapping
- Injecting a MSI to VM
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Each vGPU expects a golden virtual HW state, which is just the state after
system is freshly powered on. GVT-g will try to load the golden virtual HW
state via kernel firmware interface.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces a framework for tracking HW registers on different
GEN platforms.
Accesses to GEN HW registers from VMs will be trapped by hypervisor. It
will forward these emulation requests to GVT-g device model, which
requires this framework to search for related register descriptions.
Each MMIO entry in this framework describes a GEN HW registers, e.g.
offset, length, whether it contains RO bits, whether it can be accessed by
LRIs...and also emulation handlers for emulating register reading and
writing.
- Use i915 MMIO register definition & statement.(Joonas)
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces the GVT-g vGPU HW resource management. Under
GVT-g virtualizaion environment, each vGPU requires portions HW
resources, including aperture, hidden GM space, and fence registers.
When creating a vGPU, GVT-g will request these HW resources from host,
and return them to host after a vGPU is destroyed.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces the very basic framework of GVT-g device model,
includes basic prototypes, definitions, initialization.
v12:
- Call intel_gvt_init() in driver early initialization stage. (Chris)
v8:
- Remove the GVT idr and mutex in intel_gvt_host. (Joonas)
v7:
- Refine the URL link in Kconfig. (Joonas)
- Refine the introduction of GVT-g host support in Kconfig. (Joonas)
- Remove the macro GVT_ALIGN(), use round_down() instead. (Joonas)
- Make "struct intel_gvt" a data member in struct drm_i915_private.(Joonas)
- Remove {alloc, free}_gvt_device()
- Rename intel_gvt_{create, destroy}_gvt_device()
- Expost intel_gvt_init_host()
- Remove the dummy "struct intel_gvt" declaration in intel_gvt.h (Joonas)
v6:
- Refine introduction in Kconfig. (Chris)
- The exposed API functions will take struct intel_gvt * instead of
void *. (Chris/Tvrtko)
- Remove most memebers of strct intel_gvt_device_info. Will add them
in the device model patches.(Chris)
- Remove gvt_info() and gvt_err() in debug.h. (Chris)
- Move GVT kernel parameter into i915_params. (Chris)
- Remove include/drm/i915_gvt.h, as GVT-g will be built within i915.
- Remove the redundant struct i915_gvt *, as the functions in i915
will directly take struct intel_gvt *.
- Add more comments for reviewer.
v5:
Take Tvrtko's comments:
- Fix the misspelled words in Kconfig
- Let functions take drm_i915_private * instead of struct drm_device *
- Remove redundant prints/local varible initialization
v3:
Take Joonas' comments:
- Change file name i915_gvt.* to intel_gvt.*
- Move GVT kernel parameter into intel_gvt.c
- Remove redundant debug macros
- Change error handling style
- Add introductions for some stub functions
- Introduce drm/i915_gvt.h.
Take Kevin's comments:
- Move GVT-g host/guest check into intel_vgt_balloon in i915_gem_gtt.c
v2:
- Introduce i915_gvt.c.
It's necessary to introduce the stubs between i915 driver and GVT-g host,
as GVT-g components is configurable in kernel config. When disabled, the
stubs here do nothing.
Take Joonas' comments:
- Replace boolean return value with int.
- Replace customized info/warn/debug macros with DRM macros.
- Document all non-static functions like i915.
- Remove empty and unused functions.
- Replace magic number with marcos.
- Set GVT-g in kernel config to "n" by default.
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1466078825-6662-5-git-send-email-zhi.a.wang@intel.com
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Hang Yuan