[PATCH 6.1 113/197] drm/msm: Wire up tlb ops

Greg Kroah-Hartman
2024-02-20T21:03:48Z

From: Rob Clark <robdclark@chromium.org>

commit 8c7bfd8262319fd3f127a5380f593ea76f1b88a2 upstream.

The brute force iommu_flush_iotlb_all() was good enough for unmap, but
in some cases a map operation could require removing a table pte entry
to replace with a block entry. This also requires tlb invalidation.
Missing this was resulting an obscure iova fault on what should be a
valid buffer address.

Thanks to Robin Murphy for helping me understand the cause of the fault.

Cc: Robin Murphy <robin.murphy@arm.com>
Cc: stable@vger.kernel.org
Fixes: b145c6e65eb0 ("drm/msm: Add support to create a local pagetable")
Signed-off-by: Rob Clark <robdclark@chromium.org>
Patchwork: https://patchwork.freedesktop.org/patch/578117/
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpu/drm/msm/msm_iommu.c | 32 +++++++++++++++++++++++++++++---
1 file changed, 29 insertions(+), 3 deletions(-)

--- a/drivers/gpu/drm/msm/msm_iommu.c
+++ b/drivers/gpu/drm/msm/msm_iommu.c
@@ -21,6 +21,8 @@ struct msm_iommu_pagetable {
struct msm_mmu base;
struct msm_mmu *parent;
struct io_pgtable_ops *pgtbl_ops;
+ const struct iommu_flush_ops *tlb;
+ struct device *iommu_dev;
unsigned long pgsize_bitmap; /* Bitmap of page sizes in use */
phys_addr_t ttbr;
u32 asid;
@@ -194,11 +196,33 @@ static const struct msm_mmu_funcs pageta

static void msm_iommu_tlb_flush_all(void *cookie)
{
+ struct msm_iommu_pagetable *pagetable = cookie;
+ struct adreno_smmu_priv *adreno_smmu;
+
+ if (!pm_runtime_get_if_in_use(pagetable->iommu_dev))
+ return;
+
+ adreno_smmu = dev_get_drvdata(pagetable->parent->dev);
+
+ pagetable->tlb->tlb_flush_all((void *)adreno_smmu->cookie);
+
+ pm_runtime_put_autosuspend(pagetable->iommu_dev);
}

static void msm_iommu_tlb_flush_walk(unsigned long iova, size_t size,
size_t granule, void *cookie)
{
+ struct msm_iommu_pagetable *pagetable = cookie;
+ struct adreno_smmu_priv *adreno_smmu;
+
+ if (!pm_runtime_get_if_in_use(pagetable->iommu_dev))
+ return;
+
+ adreno_smmu = dev_get_drvdata(pagetable->parent->dev);
+
+ pagetable->tlb->tlb_flush_walk(iova, size, granule, (void *)adreno_smmu->cookie);
+
+ pm_runtime_put_autosuspend(pagetable->iommu_dev);
}

static void msm_iommu_tlb_add_page(struct iommu_iotlb_gather *gather,
@@ -206,7 +230,7 @@ static void msm_iommu_tlb_add_page(struc
{
}

-static const struct iommu_flush_ops null_tlb_ops = {
+static const struct iommu_flush_ops tlb_ops = {
.tlb_flush_all = msm_iommu_tlb_flush_all,
.tlb_flush_walk = msm_iommu_tlb_flush_walk,
.tlb_add_page = msm_iommu_tlb_add_page,
@@ -254,10 +278,10 @@ struct msm_mmu *msm_iommu_pagetable_crea

/* The incoming cfg will have the TTBR1 quirk enabled */
ttbr0_cfg.quirks &= ~IO_PGTABLE_QUIRK_ARM_TTBR1;
- ttbr0_cfg.tlb = &null_tlb_ops;
+ ttbr0_cfg.tlb = &tlb_ops;

pagetable->pgtbl_ops = alloc_io_pgtable_ops(ARM_64_LPAE_S1,
- &ttbr0_cfg, iommu->domain);
+ &ttbr0_cfg, pagetable);

if (!pagetable->pgtbl_ops) {
kfree(pagetable);
@@ -282,6 +306,8 @@ struct msm_mmu *msm_iommu_pagetable_crea

/* Needed later for TLB flush */
pagetable->parent = parent;
+ pagetable->tlb = ttbr1_cfg->tlb;
+ pagetable->iommu_dev = ttbr1_cfg->iommu_dev;
pagetable->pgsize_bitmap = ttbr0_cfg.pgsize_bitmap;
pagetable->ttbr = ttbr0_cfg.arm_lpae_s1_cfg.ttbr;