drm/vmwgfx: Abstract placement selection

Problem with explicit placement selection in vmwgfx is that by the time
the buffer object needs to be validated the information about which
placement was supposed to be used is lost. To workaround this the driver
had a bunch of state in various places e.g. as_mob or cpu_blit to
somehow convey the information on which placement was intended.

Fix it properly by allowing the buffer objects to hold their preferred
placement so it can be reused whenever needed. This makes the entire
validation pipeline a lot easier both to understand and maintain.

Signed-off-by: Zack Rusin <zackr@vmware.com>
Reviewed-by: Martin Krastev <krastevm@vmware.com>
Reviewed-by: Maaz Mombasawala <mombasawalam@vmware.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230131033542.953249-8-zack@kde.org

drm/vmwgfx: Rename vmw_buffer_object to vmw_bo

The rest of the drivers which are using ttm have mostly standardized on
driver_prefix_bo as the name for subclasses of the TTM buffer object.
Make vmwgfx match the rest of the drivers and follow the same naming
semantics.

This is especially clear given that the name of the file in which the
object was defined is vmw_bo.c.

Signed-off-by: Zack Rusin <zackr@vmware.com>
Reviewed-by: Martin Krastev <krastevm@vmware.com>
Reviewed-by: Maaz Mombasawala <mombasawalam@vmware.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230131033542.953249-4-zack@kde.org

drm/vmwgfx: Refactor resource validation hashtable to use linux/hashtable implementation.

Vmwgfx's hashtab implementation needs to be replaced with linux/hashtable
to reduce maintenence burden.
As part of this effort, refactor the res_ht hashtable used for resource
validation during execbuf execution to use linux/hashtable implementation.
This also refactors vmw_validation_context to use vmw_sw_context as the
container for the hashtable, whereas before it used a vmwgfx_open_hash
directly. This makes vmw_validation_context less generic, but there is
no functional change since res_ht is the only instance where validation
context used a hashtable in vmwgfx driver.

Signed-off-by: Maaz Mombasawala <mombasawalam@vmware.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Zack Rusin <zackr@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-6-zack@kde.org

drm/vmwgfx: Remove the dedicated memory accounting

vmwgfx shared very elaborate memory accounting with ttm. It was moved
from ttm to vmwgfx in change
f07069da6b4c ("drm/ttm: move memory accounting into vmwgfx v4")
but because of complexity it was hard to maintain. Some parts of the code
weren't freeing memory correctly and some were missing accounting all
together. While those would be fairly easy to fix the fundamental reason
for memory accounting in the driver was the ability to invoke shrinker
which is part of TTM code as well (with support for unified memory
hopefully coming soon).

That meant that vmwgfx had a lot of code that was either unused or
duplicating code from TTM. Removing this code also prevents excessive
calls to global swapout which were common during memory pressure
because both vmwgfx and TTM would invoke the shrinker when memory
usage reached half of RAM.

Fixes: f07069da6b4c ("drm/ttm: move memory accounting into vmwgfx v4")
Signed-off-by: Zack Rusin <zackr@vmware.com>
Reviewed-by: Martin Krastev <krastevm@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211206172620.3139754-2-zack@kde.org

drm/vmwgfx: Copy DRM hash-table code into driver

Besides some legacy code, vmwgfx is the only user of DRM's hash-
table implementation. Copy the code into the driver, so that the
core code can be retired.

No functional changes. However, the real solution for vmwgfx is to
use Linux' generic hash-table functions.

v2:
* add TODO item for updating vmwgfx (Sam)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211129094841.22499-3-tzimmermann@suse.de

drm/vmwgfx: Implement an infrastructure for write-coherent resources

This infrastructure will, for coherent resources, make sure that
from the user-space point of view, data written by the CPU is immediately
automatically available to the GPU at resource validation time.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Deepak Rawat <drawat@vmware.com>

drm/ttm: always keep BOs on the LRU

This allows blocking for BOs to become available
in the memory management.

Amdgpu is doing this for quite a while now during CS. Now
apply the new behavior to all drivers using TTM.

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Thomas Hellstrom <thellstrom@vmware.com>
Link: https://patchwork.freedesktop.org/patch/332878/

drm/vmwgfx: drop use of drmP.h in header files

To facilitate removal of drmP.h in the .c
files remove the use from header files first.
Fix fallout in the other files.

Sorted include files in blocks and sorted files
within each block in alphabetical order.

This revealed a dependency from an uapi header to a header
located below drivers/gpu/drm/vmwgfx/.
Added FIXME to remind someone to fix this.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: VMware Graphics <linux-graphics-maintainer@vmware.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Reviewed-by: Deepak Rawat <drawat@vmware.com>
Signed-off-by: Deepak Rawat <drawat@vmware.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>

Revert "Merge branch 'vmwgfx-next' of git://people.freedesktop.org/~thomash/linux into drm-next"

This reverts commit 031e610a6a21448a63dff7a0416e5e206724caac, reversing
changes made to 52d2d44eee8091e740d0d275df1311fb8373c9a9.

The mm changes in there we premature and not fully ack or reviewed by core mm folks,
I dropped the ball by merging them via this tree, so lets take em all back out.

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

drm/vmwgfx: Implement an infrastructure for write-coherent resources

This infrastructure will, for coherent resources, make sure that
from the user-space point of view, data written by the CPU is immediately
automatically available to the GPU at resource validation time.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Deepak Rawat <drawat@vmware.com>

drm/ttm: Make LRU removal optional v2

We are already doing this for DMA-buf imports and also for
amdgpu VM BOs for quite a while now.

If this doesn't run into any problems we are probably going
to stop removing BOs from the LRU altogether.

v2: drop BUG_ON from ttm_bo_add_to_lru

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Chunming Zhou <david1.zhou@amd.com>
Tested-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/vmwgfx: Be more restrictive when dirtying resources

Currently we flag resources as dirty (GPU contents not yet read back to
the backing MOB) whenever they have been part of a command stream.
Obviously many resources can't be dirty and others can only be dirty when
written to by the GPU. That is when they are either bound to the context as
render-targets, depth-stencil, copy / clear destinations and
stream-output targets, or similarly when there are corresponding views into
them.
So mark resources dirty only in these special cases. Context- and cotable
resources are always marked dirty when referenced.
This is important for upcoming emulated coherent memory, since we can avoid
issuing automatic readbacks to non-dirty resources when the CPU tries to
access part of the backing MOB.

Testing: Unigine Heaven with max GPU memory set to 256MB resulting in
heavy resource thrashing.
---
v2: Addressed review comments by Deepak Rawat.
v3: Added some documentation

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Deepak Rawat <drawat@vmware.com>

drm/vmwgfx: Protect from excessive execbuf kernel memory allocations v3

With the new validation code, a malicious user-space app could
potentially submit command streams with enough buffer-object and resource
references in them to have the resulting allocated validion nodes and
relocations make the kernel run out of GFP_KERNEL memory.

Protect from this by having the validation code reserve TTM graphics
memory when allocating.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Deepak Rawat <drawat@vmware.com>
---
v2: Removed leftover debug printouts

drm/vmwgfx: Adapt validation code for reference-free lookups

Adapt the validation code so that vmw_validation_add[res|bo] can be called
under an rcu read lock (non-sleeping) and with rcu-only protected resource-
or buffer object pointers.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>

drm/vmwgfx: Use a validation context allocator for relocations and validations

A common trait of these objects are that they are allocated during the
command validation phase and freed after command submission. Furthermore
they are accessed by a single thread only. So provide a simple unprotected
stack-like allocator from which these objects can be allocated. Their
memory is freed with the validation context when the command submission
is done.

Note that the mm subsystem maintains a per-cpu cache of single pages to
make single page allocation and freeing efficient.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>

drm/vmwgfx: Add a validation module v2

Isolate the functionality needed for reservation, validation and fencing
of vmwgfx buffer objects and resources and publish an API for this.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Reviewed-by: Deepak Rawat <drawat@vmware.com> #v1