drm/i915/gt: describe the new tlb parameter at i915_vma_resource
authorMauro Carvalho Chehab <mchehab@kernel.org>
Wed, 27 Jul 2022 12:29:56 +0000 (14:29 +0200)
committerAndi Shyti <andi.shyti@linux.intel.com>
Thu, 28 Jul 2022 12:02:27 +0000 (14:02 +0200)
commitd1051db85f6496ed9c825802bef3709f2e7d816f
treea327cb5c8ce70d28da6f5a55d097700163b81490
parent5d36acb7198b0e5eb88e6b701f9ad7b9448f8df9
drm/i915/gt: describe the new tlb parameter at i915_vma_resource

TLB cache invalidation can happen on two different situations:

1. synchronously, at __vma_put_pages();
2. asynchronously.

On the first case, TLB cache invalidation happens inside
__vma_put_pages(). So, no need to do it later on.

However, on the second case, the pages will keep in memory
until __i915_vma_evict() is called.

So, we need to store the TLB data at struct i915_vma_resource,
in order to do a TLB cache invalidation before allowing
userspace to re-use the same memory.

So, i915_vma_resource_unbind() has gained a new parameter
in order to store the TLB data at the second case.

Document it.

Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/aa55eef7e63b8f3d0f69b525db2dd2eb87e9db6b.1658924372.git.mchehab@kernel.org
drivers/gpu/drm/i915/i915_vma_resource.c