[PATCH v7 21/24] iommu/io-pgtable-arm: Support io-pgtable-arm in the hypervisor

[Mostafa Saleh <smostafa@google.com>]

To be able to populate the shadow stage-2 in the hypervisor, compile
io-pgtable-arm object for the hypervisor.

That requires the hypervisor to support iommu-pages, re-defining some
functions as address conversion and stubbing some others as DMA-API.

Signed-off-by: Mostafa Saleh <smostafa@google.com>
---
 arch/arm64/kvm/hyp/nvhe/Makefile              |  3 +-
 .../arm/arm-smmu-v3/pkvm/io-pgtable-arm-hyp.h | 68 +++++++++++++++++++
 drivers/iommu/io-pgtable-arm.c                | 39 ++++++++---
 drivers/iommu/io-pgtable-arm.h                | 17 +++++
 4 files changed, 117 insertions(+), 10 deletions(-)
 create mode 100644 drivers/iommu/arm/arm-smmu-v3/pkvm/io-pgtable-arm-hyp.h

diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile
index dcb75fb5b4f1..35ac274ab2c0 100644
--- a/arch/arm64/kvm/hyp/nvhe/Makefile
+++ b/arch/arm64/kvm/hyp/nvhe/Makefile
@@ -36,7 +36,8 @@ hyp-obj-y += $(lib-objs)
 HYP_SMMU_V3_DRV_PATH = ../../../../../drivers/iommu/arm/arm-smmu-v3
 
 hyp-obj-$(CONFIG_ARM_SMMU_V3_PKVM) += $(HYP_SMMU_V3_DRV_PATH)/pkvm/arm-smmu-v3.o \
-	$(HYP_SMMU_V3_DRV_PATH)/arm-smmu-v3-common-lib.o
+	$(HYP_SMMU_V3_DRV_PATH)/arm-smmu-v3-common-lib.o \
+	$(HYP_SMMU_V3_DRV_PATH)/../../io-pgtable-arm.o
 
 # Path to simple_ring_buffer.c
 CFLAGS_trace.nvhe.o += -I$(srctree)/kernel/trace/
diff --git a/drivers/iommu/arm/arm-smmu-v3/pkvm/io-pgtable-arm-hyp.h b/drivers/iommu/arm/arm-smmu-v3/pkvm/io-pgtable-arm-hyp.h
new file mode 100644
index 000000000000..c9d20e781aed
--- /dev/null
+++ b/drivers/iommu/arm/arm-smmu-v3/pkvm/io-pgtable-arm-hyp.h
@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef IO_PGTABLE_ARM_HYP_H_
+#define IO_PGTABLE_ARM_HYP_H_
+
+#include <nvhe/memory.h>
+#include <nvhe/iommu.h>
+
+#undef WARN_ONCE
+#define WARN_ONCE(condition, format...) WARN_ON(condition)
+
+static inline void *iommu_alloc_pages_node_sz(int nid, gfp_t gfp, size_t size)
+{
+	return pkvm_iommu_donate_pages(get_order(size));
+}
+
+static inline void iommu_free_pages(void *virt)
+{
+	pkvm_iommu_reclaim_pages(virt);
+}
+
+static inline void *arm_lpae_alloc_data(size_t size)
+{
+	return pkvm_iommu_donate_pages(get_order(size));
+}
+
+static inline void arm_lpae_free_data(void *p)
+{
+	pkvm_iommu_reclaim_pages(p);
+}
+
+#undef phys_to_virt
+#define phys_to_virt(x)		hyp_phys_to_virt(x)
+
+#undef virt_to_phys
+#define virt_to_phys(x)		hyp_virt_to_phys(x)
+
+/* Stubs used by io-pgtable-arm but no relevant for hypervisor object. */
+#undef dma_map_single
+#define dma_map_single(d, p, s, dir) (virt_to_phys(p))
+
+#undef dma_unmap_single
+#define dma_unmap_single(d, a, s, r) do { (void)(d); (void)(a); (void)(s); (void)(r); } while (0)
+
+#define dma_mapping_error(...) (0)
+
+#undef dev_err
+#define dev_err(dev, format, ...)
+
+static inline int iommu_pages_start_incoherent(void *virt, struct device *dma_dev)
+{
+	return 0;
+}
+
+static inline void iommu_pages_free_incoherent(void *virt,
+						   struct device *dma_dev)
+{
+}
+
+static inline void iommu_pages_flush_incoherent(struct device *dma_dev,
+						void *virt, size_t offset,
+						size_t len)
+{
+}
+
+struct io_pgtable_ops *kvm_alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
+						struct io_pgtable_cfg *cfg,
+						void *cookie);
+#endif /* IO_PGTABLE_ARM_HYP_H_ */
diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index 476c0e25631a..cf71087e4d3a 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -20,7 +20,6 @@
 #include <asm/barrier.h>
 
 #include "io-pgtable-arm.h"
-#include "iommu-pages.h"
 
 #define ARM_LPAE_MAX_ADDR_BITS		52
 #define ARM_LPAE_S2_MAX_CONCAT_PAGES	16
@@ -301,6 +300,7 @@ static void *__arm_lpae_alloc_pages(size_t size, gfp_t gfp,
 {
 	struct device *dev = cfg->iommu_dev;
 	void *pages;
+	int nid = dev ? dev_to_node(dev) : NUMA_NO_NODE;
 
 	/*
 	 * For very small starting-level translation tables the HW requires a
@@ -311,7 +311,7 @@ static void *__arm_lpae_alloc_pages(size_t size, gfp_t gfp,
 	if (cfg->alloc)
 		return __arm_lpae_cfg_alloc(size, gfp, cfg, cookie);
 
-	pages = iommu_alloc_pages_node_sz(dev_to_node(dev), gfp, size);
+	pages = iommu_alloc_pages_node_sz(nid, gfp, size);
 	if (!pages)
 		return NULL;
 
@@ -350,8 +350,7 @@ static void __arm_lpae_free_pages(void *pages, size_t size,
 static void __arm_lpae_sync_pte(arm_lpae_iopte *ptep, int num_entries,
 				struct io_pgtable_cfg *cfg)
 {
-	dma_sync_single_for_device(cfg->iommu_dev, __arm_lpae_dma_addr(ptep),
-				   sizeof(*ptep) * num_entries, DMA_TO_DEVICE);
+	iommu_pages_flush_incoherent(cfg->iommu_dev, ptep, 0, sizeof(*ptep) * num_entries);
 }
 
 static void __arm_lpae_clear_pte(arm_lpae_iopte *ptep, struct io_pgtable_cfg *cfg, int num_entries)
@@ -650,7 +649,7 @@ static void arm_lpae_free_pgtable(struct io_pgtable *iop)
 	struct arm_lpae_io_pgtable *data = io_pgtable_to_data(iop);
 
 	__arm_lpae_free_pgtable(data, data->start_level, data->pgd);
-	kfree(data);
+	arm_lpae_free_data(data);
 }
 
 static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
@@ -964,7 +963,7 @@ arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg)
 	if (cfg->oas > ARM_LPAE_MAX_ADDR_BITS)
 		return NULL;
 
-	data = kmalloc_obj(*data);
+	data = arm_lpae_alloc_data(sizeof(*data));
 	if (!data)
 		return NULL;
 
@@ -1091,7 +1090,7 @@ arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie)
 	return &data->iop;
 
 out_free_data:
-	kfree(data);
+	arm_lpae_free_data(data);
 	return NULL;
 }
 
@@ -1187,7 +1186,7 @@ arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
 	return &data->iop;
 
 out_free_data:
-	kfree(data);
+	arm_lpae_free_data(data);
 	return NULL;
 }
 
@@ -1266,7 +1265,7 @@ arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
 	return &data->iop;
 
 out_free_data:
-	kfree(data);
+	arm_lpae_free_data(data);
 	return NULL;
 }
 
@@ -1299,3 +1298,25 @@ struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns = {
 	.alloc	= arm_mali_lpae_alloc_pgtable,
 	.free	= arm_lpae_free_pgtable,
 };
+
+#ifdef __KVM_NVHE_HYPERVISOR__
+struct io_pgtable_ops *kvm_alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
+						struct io_pgtable_cfg *cfg,
+						void *cookie)
+{
+	struct io_pgtable *iop;
+
+	if (fmt != ARM_64_LPAE_S2)
+		return NULL;
+
+	iop = arm_64_lpae_alloc_pgtable_s2(cfg, cookie);
+	if (!iop)
+		return NULL;
+
+	iop->fmt	= fmt;
+	iop->cookie	= cookie;
+	iop->cfg	= *cfg;
+
+	return &iop->ops;
+}
+#endif
\ No newline at end of file
diff --git a/drivers/iommu/io-pgtable-arm.h b/drivers/iommu/io-pgtable-arm.h
index ba7cfdf7afa0..fd5c5ff2b550 100644
--- a/drivers/iommu/io-pgtable-arm.h
+++ b/drivers/iommu/io-pgtable-arm.h
@@ -27,4 +27,21 @@
 #define ARM_LPAE_TCR_PS_48_BIT		0x5ULL
 #define ARM_LPAE_TCR_PS_52_BIT		0x6ULL
 
+#ifndef __KVM_NVHE_HYPERVISOR__
+#include "iommu-pages.h"
+
+static inline void *arm_lpae_alloc_data(size_t size)
+{
+	return kmalloc(size, GFP_KERNEL);
+}
+
+static inline void arm_lpae_free_data(void *p)
+{
+	kfree(p);
+}
+
+#else
+#include "arm/arm-smmu-v3/pkvm/io-pgtable-arm-hyp.h"
+#endif
+
 #endif /* IO_PGTABLE_ARM_H_ */
-- 
2.55.0.141.g00534a21ce-goog