On Wed, Nov 25, 2020 at 06:24:13PM +0000, Robin Murphy wrote:
> On 2020-11-25 17:29, Robin Murphy wrote:
> >The only user of tlb_flush_leaf is a particularly hairy corner of the
> >Arm short-descriptor code, which wants a synchronous invalidation to
> >minimise the races inherent in trying to split a large page mapping.
> >This is already far enough into "here be dragons" territory that no
> >sensible caller should ever hit it, and thus it really doesn't need
> >optimising. Although using tlb_flush_walk there may technically be
> >more heavyweight than needed, it does the job and saves everyone else
> >having to carry around useless baggage.
> >
> >Signed-off-by: Robin Murphy <robin.mur...@arm.com>
> >---
> >
> >Reviewing the Mediatek TLB optimisation patches just left me thinking
> >"why do we even have this?"... Panfrost folks, this has zero functional
> >impact to you, merely wants an ack for straying outside drivers/iommu.
>
> Oops, same goes for MSM folks too - I honestly failed to even notice that
> some of the "msm_iommu" code actually lives in DRM. Maybe the fancy editor
> makes life *too* easy and I should go back to grep and vim and having to pay
> attention to paths... :)
Not a problem - having io-pgtable outside of drivers/iommu is new to most of us
too.
drm/msm LGTM.
Jordan
> Robin.
>
> > drivers/gpu/drm/msm/msm_iommu.c | 1 -
> > drivers/gpu/drm/panfrost/panfrost_mmu.c | 7 ------
> > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 7 ------
> > drivers/iommu/arm/arm-smmu/arm-smmu.c | 25 +++------------------
> > drivers/iommu/arm/arm-smmu/qcom_iommu.c | 8 -------
> > drivers/iommu/io-pgtable-arm-v7s.c | 3 +--
> > drivers/iommu/io-pgtable-arm.c | 1 -
> > drivers/iommu/ipmmu-vmsa.c | 1 -
> > drivers/iommu/msm_iommu.c | 7 ------
> > drivers/iommu/mtk_iommu.c | 1 -
> > include/linux/io-pgtable.h | 11 ---------
> > 11 files changed, 4 insertions(+), 68 deletions(-)
> >
> >diff --git a/drivers/gpu/drm/msm/msm_iommu.c
> >b/drivers/gpu/drm/msm/msm_iommu.c
> >index 22ac7c692a81..50d881794758 100644
> >--- a/drivers/gpu/drm/msm/msm_iommu.c
> >+++ b/drivers/gpu/drm/msm/msm_iommu.c
> >@@ -139,7 +139,6 @@ static void msm_iommu_tlb_add_page(struct
> >iommu_iotlb_gather *gather,
> > static const struct iommu_flush_ops null_tlb_ops = {
> > .tlb_flush_all = msm_iommu_tlb_flush_all,
> > .tlb_flush_walk = msm_iommu_tlb_flush_walk,
> >- .tlb_flush_leaf = msm_iommu_tlb_flush_walk,
> > .tlb_add_page = msm_iommu_tlb_add_page,
> > };
> >
> >diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c
> >b/drivers/gpu/drm/panfrost/panfrost_mmu.c
> >index 776448c527ea..c186914cc4f9 100644
> >--- a/drivers/gpu/drm/panfrost/panfrost_mmu.c
> >+++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c
> >@@ -347,16 +347,9 @@ static void mmu_tlb_flush_walk(unsigned long iova,
> >size_t size, size_t granule,
> > mmu_tlb_sync_context(cookie);
> > }
> >
> >-static void mmu_tlb_flush_leaf(unsigned long iova, size_t size, size_t
> >granule,
> >- void *cookie)
> >-{
> >- mmu_tlb_sync_context(cookie);
> >-}
> >-
> > static const struct iommu_flush_ops mmu_tlb_ops = {
> > .tlb_flush_all = mmu_tlb_inv_context_s1,
> > .tlb_flush_walk = mmu_tlb_flush_walk,
> >- .tlb_flush_leaf = mmu_tlb_flush_leaf,
> > };
> >
> > int panfrost_mmu_pgtable_alloc(struct panfrost_file_priv *priv)
> >diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> >b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> >index e634bbe60573..fb684a393118 100644
> >--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> >+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> >@@ -1741,16 +1741,9 @@ static void arm_smmu_tlb_inv_walk(unsigned long iova,
> >size_t size,
> > arm_smmu_tlb_inv_range(iova, size, granule, false, cookie);
> > }
> >
> >-static void arm_smmu_tlb_inv_leaf(unsigned long iova, size_t size,
> >- size_t granule, void *cookie)
> >-{
> >- arm_smmu_tlb_inv_range(iova, size, granule, true, cookie);
> >-}
> >-
> > static const struct iommu_flush_ops arm_smmu_flush_ops = {
> > .tlb_flush_all = arm_smmu_tlb_inv_context,
> > .tlb_flush_walk = arm_smmu_tlb_inv_walk,
> >- .tlb_flush_leaf = arm_smmu_tlb_inv_leaf,
> > .tlb_add_page = arm_smmu_tlb_inv_page_nosync,
> > };
> >
> >diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c
> >b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> >index dad7fa86fbd4..0b8c59922a2b 100644
> >--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
> >+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> >@@ -333,14 +333,6 @@ static void arm_smmu_tlb_inv_walk_s1(unsigned long
> >iova, size_t size,
> > arm_smmu_tlb_sync_context(cookie);
> > }
> >
> >-static void arm_smmu_tlb_inv_leaf_s1(unsigned long iova, size_t size,
> >- size_t granule, void *cookie)
> >-{
> >- arm_smmu_tlb_inv_range_s1(iova, size, granule, cookie,
> >- ARM_SMMU_CB_S1_TLBIVAL);
> >- arm_smmu_tlb_sync_context(cookie);
> >-}
> >-
> > static void arm_smmu_tlb_add_page_s1(struct iommu_iotlb_gather *gather,
> > unsigned long iova, size_t granule,
> > void *cookie)
> >@@ -357,14 +349,6 @@ static void arm_smmu_tlb_inv_walk_s2(unsigned long
> >iova, size_t size,
> > arm_smmu_tlb_sync_context(cookie);
> > }
> >
> >-static void arm_smmu_tlb_inv_leaf_s2(unsigned long iova, size_t size,
> >- size_t granule, void *cookie)
> >-{
> >- arm_smmu_tlb_inv_range_s2(iova, size, granule, cookie,
> >- ARM_SMMU_CB_S2_TLBIIPAS2L);
> >- arm_smmu_tlb_sync_context(cookie);
> >-}
> >-
> > static void arm_smmu_tlb_add_page_s2(struct iommu_iotlb_gather *gather,
> > unsigned long iova, size_t granule,
> > void *cookie)
> >@@ -373,8 +357,8 @@ static void arm_smmu_tlb_add_page_s2(struct
> >iommu_iotlb_gather *gather,
> > ARM_SMMU_CB_S2_TLBIIPAS2L);
> > }
> >
> >-static void arm_smmu_tlb_inv_any_s2_v1(unsigned long iova, size_t size,
> >- size_t granule, void *cookie)
> >+static void arm_smmu_tlb_inv_walk_s2_v1(unsigned long iova, size_t size,
> >+ size_t granule, void *cookie)
> > {
> > arm_smmu_tlb_inv_context_s2(cookie);
> > }
> >@@ -401,21 +385,18 @@ static void arm_smmu_tlb_add_page_s2_v1(struct
> >iommu_iotlb_gather *gather,
> > static const struct iommu_flush_ops arm_smmu_s1_tlb_ops = {
> > .tlb_flush_all = arm_smmu_tlb_inv_context_s1,
> > .tlb_flush_walk = arm_smmu_tlb_inv_walk_s1,
> >- .tlb_flush_leaf = arm_smmu_tlb_inv_leaf_s1,
> > .tlb_add_page = arm_smmu_tlb_add_page_s1,
> > };
> >
> > static const struct iommu_flush_ops arm_smmu_s2_tlb_ops_v2 = {
> > .tlb_flush_all = arm_smmu_tlb_inv_context_s2,
> > .tlb_flush_walk = arm_smmu_tlb_inv_walk_s2,
> >- .tlb_flush_leaf = arm_smmu_tlb_inv_leaf_s2,
> > .tlb_add_page = arm_smmu_tlb_add_page_s2,
> > };
> >
> > static const struct iommu_flush_ops arm_smmu_s2_tlb_ops_v1 = {
> > .tlb_flush_all = arm_smmu_tlb_inv_context_s2,
> >- .tlb_flush_walk = arm_smmu_tlb_inv_any_s2_v1,
> >- .tlb_flush_leaf = arm_smmu_tlb_inv_any_s2_v1,
> >+ .tlb_flush_walk = arm_smmu_tlb_inv_walk_s2_v1,
> > .tlb_add_page = arm_smmu_tlb_add_page_s2_v1,
> > };
> >
> >diff --git a/drivers/iommu/arm/arm-smmu/qcom_iommu.c
> >b/drivers/iommu/arm/arm-smmu/qcom_iommu.c
> >index b30d6c966e2c..7f280c8d5c53 100644
> >--- a/drivers/iommu/arm/arm-smmu/qcom_iommu.c
> >+++ b/drivers/iommu/arm/arm-smmu/qcom_iommu.c
> >@@ -185,13 +185,6 @@ static void qcom_iommu_tlb_flush_walk(unsigned long
> >iova, size_t size,
> > qcom_iommu_tlb_sync(cookie);
> > }
> >
> >-static void qcom_iommu_tlb_flush_leaf(unsigned long iova, size_t size,
> >- size_t granule, void *cookie)
> >-{
> >- qcom_iommu_tlb_inv_range_nosync(iova, size, granule, true, cookie);
> >- qcom_iommu_tlb_sync(cookie);
> >-}
> >-
> > static void qcom_iommu_tlb_add_page(struct iommu_iotlb_gather *gather,
> > unsigned long iova, size_t granule,
> > void *cookie)
> >@@ -202,7 +195,6 @@ static void qcom_iommu_tlb_add_page(struct
> >iommu_iotlb_gather *gather,
> > static const struct iommu_flush_ops qcom_flush_ops = {
> > .tlb_flush_all = qcom_iommu_tlb_inv_context,
> > .tlb_flush_walk = qcom_iommu_tlb_flush_walk,
> >- .tlb_flush_leaf = qcom_iommu_tlb_flush_leaf,
> > .tlb_add_page = qcom_iommu_tlb_add_page,
> > };
> >
> >diff --git a/drivers/iommu/io-pgtable-arm-v7s.c
> >b/drivers/iommu/io-pgtable-arm-v7s.c
> >index a688f22cbe3b..3cf72c100add 100644
> >--- a/drivers/iommu/io-pgtable-arm-v7s.c
> >+++ b/drivers/iommu/io-pgtable-arm-v7s.c
> >@@ -584,7 +584,7 @@ static arm_v7s_iopte arm_v7s_split_cont(struct
> >arm_v7s_io_pgtable *data,
> > __arm_v7s_pte_sync(ptep, ARM_V7S_CONT_PAGES, &iop->cfg);
> >
> > size *= ARM_V7S_CONT_PAGES;
> >- io_pgtable_tlb_flush_leaf(iop, iova, size, size);
> >+ io_pgtable_tlb_flush_walk(iop, iova, size, size);
> > return pte;
> > }
> >
> >@@ -866,7 +866,6 @@ static void __init dummy_tlb_add_page(struct
> >iommu_iotlb_gather *gather,
> > static const struct iommu_flush_ops dummy_tlb_ops __initconst = {
> > .tlb_flush_all = dummy_tlb_flush_all,
> > .tlb_flush_walk = dummy_tlb_flush,
> >- .tlb_flush_leaf = dummy_tlb_flush,
> > .tlb_add_page = dummy_tlb_add_page,
> > };
> >
> >diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
> >index a7a9bc08dcd1..938830e07dcf 100644
> >--- a/drivers/iommu/io-pgtable-arm.c
> >+++ b/drivers/iommu/io-pgtable-arm.c
> >@@ -1079,7 +1079,6 @@ static void __init dummy_tlb_add_page(struct
> >iommu_iotlb_gather *gather,
> > static const struct iommu_flush_ops dummy_tlb_ops __initconst = {
> > .tlb_flush_all = dummy_tlb_flush_all,
> > .tlb_flush_walk = dummy_tlb_flush,
> >- .tlb_flush_leaf = dummy_tlb_flush,
> > .tlb_add_page = dummy_tlb_add_page,
> > };
> >
> >diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
> >index 0f18abda0e20..d71f10257f15 100644
> >--- a/drivers/iommu/ipmmu-vmsa.c
> >+++ b/drivers/iommu/ipmmu-vmsa.c
> >@@ -325,7 +325,6 @@ static void ipmmu_tlb_flush(unsigned long iova, size_t
> >size,
> > static const struct iommu_flush_ops ipmmu_flush_ops = {
> > .tlb_flush_all = ipmmu_tlb_flush_all,
> > .tlb_flush_walk = ipmmu_tlb_flush,
> >- .tlb_flush_leaf = ipmmu_tlb_flush,
> > };
> >
> > /*
> > -----------------------------------------------------------------------------
> >diff --git a/drivers/iommu/msm_iommu.c b/drivers/iommu/msm_iommu.c
> >index 3615cd6241c4..040e85f70861 100644
> >--- a/drivers/iommu/msm_iommu.c
> >+++ b/drivers/iommu/msm_iommu.c
> >@@ -174,12 +174,6 @@ static void __flush_iotlb_walk(unsigned long iova,
> >size_t size,
> > __flush_iotlb_range(iova, size, granule, false, cookie);
> > }
> >
> >-static void __flush_iotlb_leaf(unsigned long iova, size_t size,
> >- size_t granule, void *cookie)
> >-{
> >- __flush_iotlb_range(iova, size, granule, true, cookie);
> >-}
> >-
> > static void __flush_iotlb_page(struct iommu_iotlb_gather *gather,
> > unsigned long iova, size_t granule, void *cookie)
> > {
> >@@ -189,7 +183,6 @@ static void __flush_iotlb_page(struct iommu_iotlb_gather
> >*gather,
> > static const struct iommu_flush_ops msm_iommu_flush_ops = {
> > .tlb_flush_all = __flush_iotlb,
> > .tlb_flush_walk = __flush_iotlb_walk,
> >- .tlb_flush_leaf = __flush_iotlb_leaf,
> > .tlb_add_page = __flush_iotlb_page,
> > };
> >
> >diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
> >index c072cee532c2..8e56cec532e7 100644
> >--- a/drivers/iommu/mtk_iommu.c
> >+++ b/drivers/iommu/mtk_iommu.c
> >@@ -240,7 +240,6 @@ static void mtk_iommu_tlb_flush_page_nosync(struct
> >iommu_iotlb_gather *gather,
> > static const struct iommu_flush_ops mtk_iommu_flush_ops = {
> > .tlb_flush_all = mtk_iommu_tlb_flush_all,
> > .tlb_flush_walk = mtk_iommu_tlb_flush_range_sync,
> >- .tlb_flush_leaf = mtk_iommu_tlb_flush_range_sync,
> > .tlb_add_page = mtk_iommu_tlb_flush_page_nosync,
> > };
> >
> >diff --git a/include/linux/io-pgtable.h b/include/linux/io-pgtable.h
> >index 4cde111e425b..ec9fae37c0e4 100644
> >--- a/include/linux/io-pgtable.h
> >+++ b/include/linux/io-pgtable.h
> >@@ -25,8 +25,6 @@ enum io_pgtable_fmt {
> > * @tlb_flush_walk: Synchronously invalidate all intermediate TLB state
> > * (sometimes referred to as the "walk cache") for a
> > virtual
> > * address range.
> >- * @tlb_flush_leaf: Synchronously invalidate all leaf TLB state for a
> >virtual
> >- * address range.
> > * @tlb_add_page: Optional callback to queue up leaf TLB invalidation
> > for a
> > * single page. IOMMUs that cannot batch TLB invalidation
> > * operations efficiently will typically issue them here,
> > but
> >@@ -40,8 +38,6 @@ struct iommu_flush_ops {
> > void (*tlb_flush_all)(void *cookie);
> > void (*tlb_flush_walk)(unsigned long iova, size_t size, size_t granule,
> > void *cookie);
> >- void (*tlb_flush_leaf)(unsigned long iova, size_t size, size_t granule,
> >- void *cookie);
> > void (*tlb_add_page)(struct iommu_iotlb_gather *gather,
> > unsigned long iova, size_t granule, void *cookie);
> > };
> >@@ -220,13 +216,6 @@ io_pgtable_tlb_flush_walk(struct io_pgtable *iop,
> >unsigned long iova,
> > iop->cfg.tlb->tlb_flush_walk(iova, size, granule, iop->cookie);
> > }
> >
> >-static inline void
> >-io_pgtable_tlb_flush_leaf(struct io_pgtable *iop, unsigned long iova,
> >- size_t size, size_t granule)
> >-{
> >- iop->cfg.tlb->tlb_flush_leaf(iova, size, granule, iop->cookie);
> >-}
> >-
> > static inline void
> > io_pgtable_tlb_add_page(struct io_pgtable *iop,
> > struct iommu_iotlb_gather * gather, unsigned long iova,
> >--
> >2.17.1
> >
> >_______________________________________________
> >iommu mailing list
> >iommu@lists.linux-foundation.org
> >https://lists.linuxfoundation.org/mailman/listinfo/iommu
> >
> _______________________________________________
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