In the MMU's page fault ISR for a heap object, determine whether the faulting address belongs to a 2MiB block that was already mapped by checking its corresponding sgt in the Panfrost BO.
This is done in preparation for a future commit in which the MMU mapping helper might fail, but the page array is left populated, so this cannot be used as a check for an early bail-out. Signed-off-by: Adrián Larumbe <[email protected]> --- drivers/gpu/drm/panfrost/panfrost_mmu.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index cf272b167feb..ba32d99ed854 100644 --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c @@ -600,10 +600,12 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as, refcount_set(&bo->base.pages_use_count, 1); } else { pages = bo->base.pages; - if (pages[page_offset]) { - /* Pages are already mapped, bail out. */ - goto out; - } + } + + sgt = &bo->sgts[page_offset / (SZ_2M / PAGE_SIZE)]; + if (sgt->sgl) { + /* Pages are already mapped, bail out. */ + goto out; } mapping = bo->base.base.filp->f_mapping; @@ -625,7 +627,6 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as, } } - sgt = &bo->sgts[page_offset / (SZ_2M / PAGE_SIZE)]; ret = sg_alloc_table_from_pages(sgt, pages + page_offset, NUM_FAULT_PAGES, 0, SZ_2M, GFP_KERNEL); if (ret) -- 2.51.0
