iommu/io-pgtable: Indicate granule for TLB maintenance

IOMMU hardware with range-based TLB maintenance commands can work
happily with the iova and size arguments passed via the tlb_add_flush
callback, but for IOMMUs which require separate commands per entry in
the range, it is not straightforward to infer the necessary granularity
when it comes to issuing the actual commands.

Add an additional argument indicating the granularity for the benefit
of drivers needing to know, and update the ARM LPAE code appropriately
(for non-leaf invalidations we currently just assume the worst-case
page granularity rather than walking the table to check).

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

drivers/iommu/arm-smmu-v3.c

@@ -1341,7 +1341,7 @@ static void arm_smmu_tlb_inv_context(void *cookie)
 }
 
 static void arm_smmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
-					  bool leaf, void *cookie)
+					  size_t granule, bool leaf, void *cookie)
 {
 	struct arm_smmu_domain *smmu_domain = cookie;
 	struct arm_smmu_device *smmu = smmu_domain->smmu;

drivers/iommu/arm-smmu.c

@@ -582,7 +582,7 @@ static void arm_smmu_tlb_inv_context(void *cookie)
 }
 
 static void arm_smmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
-					  bool leaf, void *cookie)
+					  size_t granule, bool leaf, void *cookie)
 {
 	struct arm_smmu_domain *smmu_domain = cookie;
 	struct arm_smmu_cfg *cfg = &smmu_domain->cfg;

drivers/iommu/io-pgtable-arm.c

@@ -58,8 +58,10 @@
 	((((d)->levels - ((l) - ARM_LPAE_START_LVL(d) + 1))		\
 	  * (d)->bits_per_level) + (d)->pg_shift)
 
+#define ARM_LPAE_GRANULE(d)		(1UL << (d)->pg_shift)
+
 #define ARM_LPAE_PAGES_PER_PGD(d)					\
-	DIV_ROUND_UP((d)->pgd_size, 1UL << (d)->pg_shift)
+	DIV_ROUND_UP((d)->pgd_size, ARM_LPAE_GRANULE(d))
 
 /*
  * Calculate the index at level l used to map virtual address a using the
@@ -169,7 +171,7 @@
 /* IOPTE accessors */
 #define iopte_deref(pte,d)					\
 	(__va((pte) & ((1ULL << ARM_LPAE_MAX_ADDR_BITS) - 1)	\
-	& ~((1ULL << (d)->pg_shift) - 1)))
+	& ~(ARM_LPAE_GRANULE(d) - 1ULL)))
 
 #define iopte_type(pte,l)					\
 	(((pte) >> ARM_LPAE_PTE_TYPE_SHIFT) & ARM_LPAE_PTE_TYPE_MASK)
@@ -326,7 +328,7 @@ static int __arm_lpae_map(struct arm_lpae_io_pgtable *data, unsigned long iova,
 	/* Grab a pointer to the next level */
 	pte = *ptep;
 	if (!pte) {
-		cptep = __arm_lpae_alloc_pages(1UL << data->pg_shift,
+		cptep = __arm_lpae_alloc_pages(ARM_LPAE_GRANULE(data),
 					       GFP_ATOMIC, cfg);
 		if (!cptep)
 			return -ENOMEM;
@@ -412,7 +414,7 @@ static void __arm_lpae_free_pgtable(struct arm_lpae_io_pgtable *data, int lvl,
 	if (lvl == ARM_LPAE_START_LVL(data))
 		table_size = data->pgd_size;
 	else
-		table_size = 1UL << data->pg_shift;
+		table_size = ARM_LPAE_GRANULE(data);
 
 	start = ptep;
 	end = (void *)ptep + table_size;
@@ -473,7 +475,7 @@ static int arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data,
 
 	__arm_lpae_set_pte(ptep, table, cfg);
 	iova &= ~(blk_size - 1);
-	cfg->tlb->tlb_add_flush(iova, blk_size, true, data->iop.cookie);
+	cfg->tlb->tlb_add_flush(iova, blk_size, blk_size, true, data->iop.cookie);
 	return size;
 }
 
@@ -501,12 +503,13 @@ static int __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
 
 		if (!iopte_leaf(pte, lvl)) {
 			/* Also flush any partial walks */
-			tlb->tlb_add_flush(iova, size, false, cookie);
+			tlb->tlb_add_flush(iova, size, ARM_LPAE_GRANULE(data),
+					   false, cookie);
 			tlb->tlb_sync(cookie);
 			ptep = iopte_deref(pte, data);
 			__arm_lpae_free_pgtable(data, lvl + 1, ptep);
 		} else {
-			tlb->tlb_add_flush(iova, size, true, cookie);
+			tlb->tlb_add_flush(iova, size, size, true, cookie);
 		}
 
 		return size;
@@ -572,7 +575,7 @@ static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,
 	return 0;
 
 found_translation:
-	iova &= ((1 << data->pg_shift) - 1);
+	iova &= (ARM_LPAE_GRANULE(data) - 1);
 	return ((phys_addr_t)iopte_to_pfn(pte,data) << data->pg_shift) | iova;
 }
 
@@ -670,7 +673,7 @@ arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie)
 	      (ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_IRGN0_SHIFT) |
 	      (ARM_LPAE_TCR_RGN_WBWA << ARM_LPAE_TCR_ORGN0_SHIFT);
 
-	switch (1 << data->pg_shift) {
+	switch (ARM_LPAE_GRANULE(data)) {
 	case SZ_4K:
 		reg |= ARM_LPAE_TCR_TG0_4K;
 		break;
@@ -771,7 +774,7 @@ arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
 
 	sl = ARM_LPAE_START_LVL(data);
 
-	switch (1 << data->pg_shift) {
+	switch (ARM_LPAE_GRANULE(data)) {
 	case SZ_4K:
 		reg |= ARM_LPAE_TCR_TG0_4K;
 		sl++; /* SL0 format is different for 4K granule size */
@@ -891,8 +894,8 @@ static void dummy_tlb_flush_all(void *cookie)
 	WARN_ON(cookie != cfg_cookie);
 }
 
-static void dummy_tlb_add_flush(unsigned long iova, size_t size, bool leaf,
-				void *cookie)
+static void dummy_tlb_add_flush(unsigned long iova, size_t size,
+				size_t granule, bool leaf, void *cookie)
 {
 	WARN_ON(cookie != cfg_cookie);
 	WARN_ON(!(size & cfg_cookie->pgsize_bitmap));

drivers/iommu/io-pgtable.h

@@ -26,8 +26,8 @@ enum io_pgtable_fmt {
  */
 struct iommu_gather_ops {
 	void (*tlb_flush_all)(void *cookie);
-	void (*tlb_add_flush)(unsigned long iova, size_t size, bool leaf,
-			      void *cookie);
+	void (*tlb_add_flush)(unsigned long iova, size_t size, size_t granule,
+			      bool leaf, void *cookie);
 	void (*tlb_sync)(void *cookie);
 };
 

drivers/iommu/ipmmu-vmsa.c

@@ -277,8 +277,8 @@ static void ipmmu_tlb_flush_all(void *cookie)
 	ipmmu_tlb_invalidate(domain);
 }
 
-static void ipmmu_tlb_add_flush(unsigned long iova, size_t size, bool leaf,
-				void *cookie)
+static void ipmmu_tlb_add_flush(unsigned long iova, size_t size,
+				size_t granule, bool leaf, void *cookie)
 {
 	/* The hardware doesn't support selective TLB flush. */
 }