diff options
Diffstat (limited to 'drivers/gpu/drm/i915/i915_gem_gtt.c')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_gem_gtt.c | 30 |
1 files changed, 26 insertions, 4 deletions
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index afe45cbcd762..9ea024395d49 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -580,10 +580,9 @@ setup_scratch_page(struct i915_address_space *vm, gfp_t gfp) * region, including any PTEs which happen to point to scratch. * * This is only relevant for the 48b PPGTT where we support - * huge-gtt-pages, see also i915_vma_insert(). - * - * TODO: we should really consider write-protecting the scratch-page and - * sharing between ppgtt + * huge-gtt-pages, see also i915_vma_insert(). However, as we share the + * scratch (read-only) between all vm, we create one 64k scratch page + * for all. */ size = I915_GTT_PAGE_SIZE_4K; if (i915_vm_is_48bit(vm) && @@ -1209,6 +1208,26 @@ static int gen8_init_scratch(struct i915_address_space *vm) { int ret; + /* + * If everybody agrees to not to write into the scratch page, + * we can reuse it for all vm, keeping contexts and processes separate. + */ + if (vm->has_read_only && + vm->i915->kernel_context && + vm->i915->kernel_context->ppgtt) { + struct i915_address_space *clone = + &vm->i915->kernel_context->ppgtt->vm; + + GEM_BUG_ON(!clone->has_read_only); + + vm->scratch_page.order = clone->scratch_page.order; + vm->scratch_pte = clone->scratch_pte; + vm->scratch_pt = clone->scratch_pt; + vm->scratch_pd = clone->scratch_pd; + vm->scratch_pdp = clone->scratch_pdp; + return 0; + } + ret = setup_scratch_page(vm, __GFP_HIGHMEM); if (ret) return ret; @@ -1289,6 +1308,9 @@ static int gen8_ppgtt_notify_vgt(struct i915_hw_ppgtt *ppgtt, bool create) static void gen8_free_scratch(struct i915_address_space *vm) { + if (!vm->scratch_page.daddr) + return; + if (use_4lvl(vm)) free_pdp(vm, vm->scratch_pdp); free_pd(vm, vm->scratch_pd); |