[PATCH v3 0/6] ONE_REG interface for SBI FWFT extension

[PATCH v3 0/6] ONE_REG interface for SBI FWFT extension

[Anup Patel]

This series adds ONE_REG interface for SBI FWFT extension implemented
by KVM RISC-V. This was missed out in accepted SBI FWFT patches for
KVM RISC-V.

These patches can also be found in the riscv_kvm_fwft_one_reg_v3 branch
at: https://github.com/avpatel/linux.git

Changes since v2:
 - Re-based on latest KVM RISC-V queue
 - Improved FWFT ONE_REG interface to allow enabling/disabling each
   FWFT feature from KVM userspace

Changes since v1:
 - Dropped have_state in PATCH4 as suggested by Drew
 - Added Drew's Reviewed-by in appropriate patches

Anup Patel (6):
  RISC-V: KVM: Set initial value of hedeleg in kvm_arch_vcpu_create()
  RISC-V: KVM: Introduce feature specific reset for SBI FWFT
  RISC-V: KVM: Introduce optional ONE_REG callbacks for SBI extensions
  RISC-V: KVM: Move copy_sbi_ext_reg_indices() to SBI implementation
  RISC-V: KVM: Implement ONE_REG interface for SBI FWFT state
  KVM: riscv: selftests: Add SBI FWFT to get-reg-list test

 arch/riscv/include/asm/kvm_vcpu_sbi.h         |  22 +-
 arch/riscv/include/asm/kvm_vcpu_sbi_fwft.h    |   1 +
 arch/riscv/include/uapi/asm/kvm.h             |  15 ++
 arch/riscv/kvm/vcpu.c                         |   3 +-
 arch/riscv/kvm/vcpu_onereg.c                  |  60 +----
 arch/riscv/kvm/vcpu_sbi.c                     | 172 +++++++++++--
 arch/riscv/kvm/vcpu_sbi_fwft.c                | 227 ++++++++++++++++--
 arch/riscv/kvm/vcpu_sbi_sta.c                 |  63 +++--
 .../selftests/kvm/riscv/get-reg-list.c        |  32 +++
 9 files changed, 467 insertions(+), 128 deletions(-)

-- 
2.43.0

[PATCH v3 1/6] RISC-V: KVM: Set initial value of hedeleg in kvm_arch_vcpu_create()

[Anup Patel]

The hedeleg may be updated by ONE_REG interface before the VCPU
is run at least once hence set the initial value of hedeleg in
kvm_arch_vcpu_create() instead of kvm_riscv_vcpu_setup_config().

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
---
 arch/riscv/kvm/vcpu.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c
index 3ebcfffaa978..47bcf190ccc5 100644
--- a/arch/riscv/kvm/vcpu.c
+++ b/arch/riscv/kvm/vcpu.c
@@ -133,6 +133,8 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 
 	/* Mark this VCPU never ran */
 	vcpu->arch.ran_atleast_once = false;
+
+	vcpu->arch.cfg.hedeleg = KVM_HEDELEG_DEFAULT;
 	vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
 	bitmap_zero(vcpu->arch.isa, RISCV_ISA_EXT_MAX);
 
@@ -570,7 +572,6 @@ static void kvm_riscv_vcpu_setup_config(struct kvm_vcpu *vcpu)
 			cfg->hstateen0 |= SMSTATEEN0_SSTATEEN0;
 	}
 
-	cfg->hedeleg = KVM_HEDELEG_DEFAULT;
 	if (vcpu->guest_debug)
 		cfg->hedeleg &= ~BIT(EXC_BREAKPOINT);
 }
-- 
2.43.0

[PATCH v3 2/6] RISC-V: KVM: Introduce feature specific reset for SBI FWFT

[Anup Patel]

The SBI FWFT feature values must be reset upon VCPU reset so
introduce feature specific reset callback for this purpose.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
---
 arch/riscv/kvm/vcpu_sbi_fwft.c | 30 ++++++++++++++++++++++++++++--
 1 file changed, 28 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/kvm/vcpu_sbi_fwft.c b/arch/riscv/kvm/vcpu_sbi_fwft.c
index 164a01288b0a..5a3bad0f9330 100644
--- a/arch/riscv/kvm/vcpu_sbi_fwft.c
+++ b/arch/riscv/kvm/vcpu_sbi_fwft.c
@@ -30,6 +30,13 @@ struct kvm_sbi_fwft_feature {
 	 */
 	bool (*supported)(struct kvm_vcpu *vcpu);
 
+	/**
+	 * @reset: Reset the feature value irrespective whether feature is supported or not
+	 *
+	 * This callback is mandatory
+	 */
+	void (*reset)(struct kvm_vcpu *vcpu);
+
 	/**
 	 * @set: Set the feature value
 	 *
@@ -75,6 +82,13 @@ static bool kvm_sbi_fwft_misaligned_delegation_supported(struct kvm_vcpu *vcpu)
 	return misaligned_traps_can_delegate();
 }
 
+static void kvm_sbi_fwft_reset_misaligned_delegation(struct kvm_vcpu *vcpu)
+{
+	struct kvm_vcpu_config *cfg = &vcpu->arch.cfg;
+
+	cfg->hedeleg &= ~MIS_DELEG;
+}
+
 static long kvm_sbi_fwft_set_misaligned_delegation(struct kvm_vcpu *vcpu,
 					struct kvm_sbi_fwft_config *conf,
 					unsigned long value)
@@ -124,6 +138,11 @@ static bool kvm_sbi_fwft_pointer_masking_pmlen_supported(struct kvm_vcpu *vcpu)
 	return fwft->have_vs_pmlen_7 || fwft->have_vs_pmlen_16;
 }
 
+static void kvm_sbi_fwft_reset_pointer_masking_pmlen(struct kvm_vcpu *vcpu)
+{
+	vcpu->arch.cfg.henvcfg &= ~ENVCFG_PMM;
+}
+
 static long kvm_sbi_fwft_set_pointer_masking_pmlen(struct kvm_vcpu *vcpu,
 						   struct kvm_sbi_fwft_config *conf,
 						   unsigned long value)
@@ -180,6 +199,7 @@ static const struct kvm_sbi_fwft_feature features[] = {
 	{
 		.id = SBI_FWFT_MISALIGNED_EXC_DELEG,
 		.supported = kvm_sbi_fwft_misaligned_delegation_supported,
+		.reset = kvm_sbi_fwft_reset_misaligned_delegation,
 		.set = kvm_sbi_fwft_set_misaligned_delegation,
 		.get = kvm_sbi_fwft_get_misaligned_delegation,
 	},
@@ -187,6 +207,7 @@ static const struct kvm_sbi_fwft_feature features[] = {
 	{
 		.id = SBI_FWFT_POINTER_MASKING_PMLEN,
 		.supported = kvm_sbi_fwft_pointer_masking_pmlen_supported,
+		.reset = kvm_sbi_fwft_reset_pointer_masking_pmlen,
 		.set = kvm_sbi_fwft_set_pointer_masking_pmlen,
 		.get = kvm_sbi_fwft_get_pointer_masking_pmlen,
 	},
@@ -321,11 +342,16 @@ static void kvm_sbi_ext_fwft_deinit(struct kvm_vcpu *vcpu)
 
 static void kvm_sbi_ext_fwft_reset(struct kvm_vcpu *vcpu)
 {
-	int i;
 	struct kvm_sbi_fwft *fwft = vcpu_to_fwft(vcpu);
+	const struct kvm_sbi_fwft_feature *feature;
+	int i;
 
-	for (i = 0; i < ARRAY_SIZE(features); i++)
+	for (i = 0; i < ARRAY_SIZE(features); i++) {
 		fwft->configs[i].flags = 0;
+		feature = &features[i];
+		if (feature->reset)
+			feature->reset(vcpu);
+	}
 }
 
 const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_fwft = {
-- 
2.43.0

[PATCH v3 3/6] RISC-V: KVM: Introduce optional ONE_REG callbacks for SBI extensions

[Anup Patel]

SBI extensions can have per-VCPU state which needs to be saved/restored
through ONE_REG interface for Guest/VM migration. Introduce optional
ONE_REG callbacks for SBI extensions so that ONE_REG implementation
for an SBI extenion is part of the extension sources.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
---
 arch/riscv/include/asm/kvm_vcpu_sbi.h |  20 ++--
 arch/riscv/kvm/vcpu_onereg.c          |  31 +-----
 arch/riscv/kvm/vcpu_sbi.c             | 145 ++++++++++++++++++++++----
 arch/riscv/kvm/vcpu_sbi_sta.c         |  63 +++++++----
 4 files changed, 176 insertions(+), 83 deletions(-)

diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h
index 766031e80960..8970cc7530c4 100644
--- a/arch/riscv/include/asm/kvm_vcpu_sbi.h
+++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h
@@ -59,6 +59,14 @@ struct kvm_vcpu_sbi_extension {
 	void (*deinit)(struct kvm_vcpu *vcpu);
 
 	void (*reset)(struct kvm_vcpu *vcpu);
+
+	unsigned long state_reg_subtype;
+	unsigned long (*get_state_reg_count)(struct kvm_vcpu *vcpu);
+	int (*get_state_reg_id)(struct kvm_vcpu *vcpu, int index, u64 *reg_id);
+	int (*get_state_reg)(struct kvm_vcpu *vcpu, unsigned long reg_num,
+			     unsigned long reg_size, void *reg_val);
+	int (*set_state_reg)(struct kvm_vcpu *vcpu, unsigned long reg_num,
+			     unsigned long reg_size, const void *reg_val);
 };
 
 void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, struct kvm_run *run);
@@ -73,10 +81,9 @@ int kvm_riscv_vcpu_set_reg_sbi_ext(struct kvm_vcpu *vcpu,
 				   const struct kvm_one_reg *reg);
 int kvm_riscv_vcpu_get_reg_sbi_ext(struct kvm_vcpu *vcpu,
 				   const struct kvm_one_reg *reg);
-int kvm_riscv_vcpu_set_reg_sbi(struct kvm_vcpu *vcpu,
-			       const struct kvm_one_reg *reg);
-int kvm_riscv_vcpu_get_reg_sbi(struct kvm_vcpu *vcpu,
-			       const struct kvm_one_reg *reg);
+int kvm_riscv_vcpu_reg_indices_sbi(struct kvm_vcpu *vcpu, u64 __user *uindices);
+int kvm_riscv_vcpu_set_reg_sbi(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
+int kvm_riscv_vcpu_get_reg_sbi(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
 const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext(
 				struct kvm_vcpu *vcpu, unsigned long extid);
 bool riscv_vcpu_supports_sbi_ext(struct kvm_vcpu *vcpu, int idx);
@@ -85,11 +92,6 @@ void kvm_riscv_vcpu_sbi_init(struct kvm_vcpu *vcpu);
 void kvm_riscv_vcpu_sbi_deinit(struct kvm_vcpu *vcpu);
 void kvm_riscv_vcpu_sbi_reset(struct kvm_vcpu *vcpu);
 
-int kvm_riscv_vcpu_get_reg_sbi_sta(struct kvm_vcpu *vcpu, unsigned long reg_num,
-				   unsigned long *reg_val);
-int kvm_riscv_vcpu_set_reg_sbi_sta(struct kvm_vcpu *vcpu, unsigned long reg_num,
-				   unsigned long reg_val);
-
 #ifdef CONFIG_RISCV_SBI_V01
 extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_v01;
 #endif
diff --git a/arch/riscv/kvm/vcpu_onereg.c b/arch/riscv/kvm/vcpu_onereg.c
index 9f8b196e7697..0f4e444e5e10 100644
--- a/arch/riscv/kvm/vcpu_onereg.c
+++ b/arch/riscv/kvm/vcpu_onereg.c
@@ -1112,36 +1112,9 @@ static unsigned long num_sbi_ext_regs(struct kvm_vcpu *vcpu)
 	return copy_sbi_ext_reg_indices(vcpu, NULL);
 }
 
-static int copy_sbi_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
-{
-	struct kvm_vcpu_sbi_context *scontext = &vcpu->arch.sbi_context;
-	int total = 0;
-
-	if (scontext->ext_status[KVM_RISCV_SBI_EXT_STA] == KVM_RISCV_SBI_EXT_STATUS_ENABLED) {
-		u64 size = IS_ENABLED(CONFIG_32BIT) ? KVM_REG_SIZE_U32 : KVM_REG_SIZE_U64;
-		int n = sizeof(struct kvm_riscv_sbi_sta) / sizeof(unsigned long);
-
-		for (int i = 0; i < n; i++) {
-			u64 reg = KVM_REG_RISCV | size |
-				  KVM_REG_RISCV_SBI_STATE |
-				  KVM_REG_RISCV_SBI_STA | i;
-
-			if (uindices) {
-				if (put_user(reg, uindices))
-					return -EFAULT;
-				uindices++;
-			}
-		}
-
-		total += n;
-	}
-
-	return total;
-}
-
 static inline unsigned long num_sbi_regs(struct kvm_vcpu *vcpu)
 {
-	return copy_sbi_reg_indices(vcpu, NULL);
+	return kvm_riscv_vcpu_reg_indices_sbi(vcpu, NULL);
 }
 
 static inline unsigned long num_vector_regs(const struct kvm_vcpu *vcpu)
@@ -1269,7 +1242,7 @@ int kvm_riscv_vcpu_copy_reg_indices(struct kvm_vcpu *vcpu,
 		return ret;
 	uindices += ret;
 
-	ret = copy_sbi_reg_indices(vcpu, uindices);
+	ret = kvm_riscv_vcpu_reg_indices_sbi(vcpu, uindices);
 	if (ret < 0)
 		return ret;
 	uindices += ret;
diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c
index 01a93f4fdb16..04903e5012d6 100644
--- a/arch/riscv/kvm/vcpu_sbi.c
+++ b/arch/riscv/kvm/vcpu_sbi.c
@@ -364,64 +364,163 @@ int kvm_riscv_vcpu_get_reg_sbi_ext(struct kvm_vcpu *vcpu,
 	return 0;
 }
 
-int kvm_riscv_vcpu_set_reg_sbi(struct kvm_vcpu *vcpu,
-			       const struct kvm_one_reg *reg)
+int kvm_riscv_vcpu_reg_indices_sbi(struct kvm_vcpu *vcpu, u64 __user *uindices)
+{
+	struct kvm_vcpu_sbi_context *scontext = &vcpu->arch.sbi_context;
+	const struct kvm_riscv_sbi_extension_entry *entry;
+	const struct kvm_vcpu_sbi_extension *ext;
+	unsigned long state_reg_count;
+	int i, j, rc, count = 0;
+	u64 reg;
+
+	for (i = 0; i < ARRAY_SIZE(sbi_ext); i++) {
+		entry = &sbi_ext[i];
+		ext = entry->ext_ptr;
+
+		if (!ext->get_state_reg_count ||
+		    scontext->ext_status[entry->ext_idx] != KVM_RISCV_SBI_EXT_STATUS_ENABLED)
+			continue;
+
+		state_reg_count = ext->get_state_reg_count(vcpu);
+		if (!uindices)
+			goto skip_put_user;
+
+		for (j = 0; j < state_reg_count; j++) {
+			if (ext->get_state_reg_id) {
+				rc = ext->get_state_reg_id(vcpu, j, &reg);
+				if (rc)
+					return rc;
+			} else {
+				reg = KVM_REG_RISCV |
+				      (IS_ENABLED(CONFIG_32BIT) ?
+				       KVM_REG_SIZE_U32 : KVM_REG_SIZE_U64) |
+				      KVM_REG_RISCV_SBI_STATE |
+				      ext->state_reg_subtype | j;
+			}
+
+			if (put_user(reg, uindices))
+				return -EFAULT;
+			uindices++;
+		}
+
+skip_put_user:
+		count += state_reg_count;
+	}
+
+	return count;
+}
+
+static const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext_withstate(struct kvm_vcpu *vcpu,
+									    unsigned long subtype)
+{
+	struct kvm_vcpu_sbi_context *scontext = &vcpu->arch.sbi_context;
+	const struct kvm_riscv_sbi_extension_entry *entry;
+	const struct kvm_vcpu_sbi_extension *ext;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(sbi_ext); i++) {
+		entry = &sbi_ext[i];
+		ext = entry->ext_ptr;
+
+		if (ext->get_state_reg_count &&
+		    ext->state_reg_subtype == subtype &&
+		    scontext->ext_status[entry->ext_idx] == KVM_RISCV_SBI_EXT_STATUS_ENABLED)
+			return ext;
+	}
+
+	return NULL;
+}
+
+int kvm_riscv_vcpu_set_reg_sbi(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 {
 	unsigned long __user *uaddr =
 			(unsigned long __user *)(unsigned long)reg->addr;
 	unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK |
 					    KVM_REG_SIZE_MASK |
 					    KVM_REG_RISCV_SBI_STATE);
-	unsigned long reg_subtype, reg_val;
-
-	if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
+	const struct kvm_vcpu_sbi_extension *ext;
+	unsigned long reg_subtype;
+	void *reg_val;
+	u64 data64;
+	u32 data32;
+	u16 data16;
+	u8 data8;
+
+	switch (KVM_REG_SIZE(reg->id)) {
+	case 1:
+		reg_val = &data8;
+		break;
+	case 2:
+		reg_val = &data16;
+		break;
+	case 4:
+		reg_val = &data32;
+		break;
+	case 8:
+		reg_val = &data64;
+		break;
+	default:
 		return -EINVAL;
+	}
 
-	if (copy_from_user(&reg_val, uaddr, KVM_REG_SIZE(reg->id)))
+	if (copy_from_user(reg_val, uaddr, KVM_REG_SIZE(reg->id)))
 		return -EFAULT;
 
 	reg_subtype = reg_num & KVM_REG_RISCV_SUBTYPE_MASK;
 	reg_num &= ~KVM_REG_RISCV_SUBTYPE_MASK;
 
-	switch (reg_subtype) {
-	case KVM_REG_RISCV_SBI_STA:
-		return kvm_riscv_vcpu_set_reg_sbi_sta(vcpu, reg_num, reg_val);
-	default:
+	ext = kvm_vcpu_sbi_find_ext_withstate(vcpu, reg_subtype);
+	if (!ext || !ext->set_state_reg)
 		return -EINVAL;
-	}
 
-	return 0;
+	return ext->set_state_reg(vcpu, reg_num, KVM_REG_SIZE(reg->id), reg_val);
 }
 
-int kvm_riscv_vcpu_get_reg_sbi(struct kvm_vcpu *vcpu,
-			       const struct kvm_one_reg *reg)
+int kvm_riscv_vcpu_get_reg_sbi(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 {
 	unsigned long __user *uaddr =
 			(unsigned long __user *)(unsigned long)reg->addr;
 	unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK |
 					    KVM_REG_SIZE_MASK |
 					    KVM_REG_RISCV_SBI_STATE);
-	unsigned long reg_subtype, reg_val;
+	const struct kvm_vcpu_sbi_extension *ext;
+	unsigned long reg_subtype;
+	void *reg_val;
+	u64 data64;
+	u32 data32;
+	u16 data16;
+	u8 data8;
 	int ret;
 
-	if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
+	switch (KVM_REG_SIZE(reg->id)) {
+	case 1:
+		reg_val = &data8;
+		break;
+	case 2:
+		reg_val = &data16;
+		break;
+	case 4:
+		reg_val = &data32;
+		break;
+	case 8:
+		reg_val = &data64;
+		break;
+	default:
 		return -EINVAL;
+	}
 
 	reg_subtype = reg_num & KVM_REG_RISCV_SUBTYPE_MASK;
 	reg_num &= ~KVM_REG_RISCV_SUBTYPE_MASK;
 
-	switch (reg_subtype) {
-	case KVM_REG_RISCV_SBI_STA:
-		ret = kvm_riscv_vcpu_get_reg_sbi_sta(vcpu, reg_num, &reg_val);
-		break;
-	default:
+	ext = kvm_vcpu_sbi_find_ext_withstate(vcpu, reg_subtype);
+	if (!ext || !ext->get_state_reg)
 		return -EINVAL;
-	}
 
+	ret = ext->get_state_reg(vcpu, reg_num, KVM_REG_SIZE(reg->id), reg_val);
 	if (ret)
 		return ret;
 
-	if (copy_to_user(uaddr, &reg_val, KVM_REG_SIZE(reg->id)))
+	if (copy_to_user(uaddr, reg_val, KVM_REG_SIZE(reg->id)))
 		return -EFAULT;
 
 	return 0;
diff --git a/arch/riscv/kvm/vcpu_sbi_sta.c b/arch/riscv/kvm/vcpu_sbi_sta.c
index cc6cb7c8f0e4..68486f90a61e 100644
--- a/arch/riscv/kvm/vcpu_sbi_sta.c
+++ b/arch/riscv/kvm/vcpu_sbi_sta.c
@@ -151,63 +151,82 @@ static unsigned long kvm_sbi_ext_sta_probe(struct kvm_vcpu *vcpu)
 	return !!sched_info_on();
 }
 
-const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_sta = {
-	.extid_start = SBI_EXT_STA,
-	.extid_end = SBI_EXT_STA,
-	.handler = kvm_sbi_ext_sta_handler,
-	.probe = kvm_sbi_ext_sta_probe,
-	.reset = kvm_riscv_vcpu_sbi_sta_reset,
-};
+static unsigned long kvm_sbi_ext_sta_get_state_reg_count(struct kvm_vcpu *vcpu)
+{
+	return sizeof(struct kvm_riscv_sbi_sta) / sizeof(unsigned long);
+}
 
-int kvm_riscv_vcpu_get_reg_sbi_sta(struct kvm_vcpu *vcpu,
-				   unsigned long reg_num,
-				   unsigned long *reg_val)
+static int kvm_sbi_ext_sta_get_reg(struct kvm_vcpu *vcpu, unsigned long reg_num,
+				   unsigned long reg_size, void *reg_val)
 {
+	unsigned long *value;
+
+	if (reg_size != sizeof(unsigned long))
+		return -EINVAL;
+	value = reg_val;
+
 	switch (reg_num) {
 	case KVM_REG_RISCV_SBI_STA_REG(shmem_lo):
-		*reg_val = (unsigned long)vcpu->arch.sta.shmem;
+		*value = (unsigned long)vcpu->arch.sta.shmem;
 		break;
 	case KVM_REG_RISCV_SBI_STA_REG(shmem_hi):
 		if (IS_ENABLED(CONFIG_32BIT))
-			*reg_val = upper_32_bits(vcpu->arch.sta.shmem);
+			*value = upper_32_bits(vcpu->arch.sta.shmem);
 		else
-			*reg_val = 0;
+			*value = 0;
 		break;
 	default:
-		return -EINVAL;
+		return -ENOENT;
 	}
 
 	return 0;
 }
 
-int kvm_riscv_vcpu_set_reg_sbi_sta(struct kvm_vcpu *vcpu,
-				   unsigned long reg_num,
-				   unsigned long reg_val)
+static int kvm_sbi_ext_sta_set_reg(struct kvm_vcpu *vcpu, unsigned long reg_num,
+				   unsigned long reg_size, const void *reg_val)
 {
+	unsigned long value;
+
+	if (reg_size != sizeof(unsigned long))
+		return -EINVAL;
+	value = *(const unsigned long *)reg_val;
+
 	switch (reg_num) {
 	case KVM_REG_RISCV_SBI_STA_REG(shmem_lo):
 		if (IS_ENABLED(CONFIG_32BIT)) {
 			gpa_t hi = upper_32_bits(vcpu->arch.sta.shmem);
 
-			vcpu->arch.sta.shmem = reg_val;
+			vcpu->arch.sta.shmem = value;
 			vcpu->arch.sta.shmem |= hi << 32;
 		} else {
-			vcpu->arch.sta.shmem = reg_val;
+			vcpu->arch.sta.shmem = value;
 		}
 		break;
 	case KVM_REG_RISCV_SBI_STA_REG(shmem_hi):
 		if (IS_ENABLED(CONFIG_32BIT)) {
 			gpa_t lo = lower_32_bits(vcpu->arch.sta.shmem);
 
-			vcpu->arch.sta.shmem = ((gpa_t)reg_val << 32);
+			vcpu->arch.sta.shmem = ((gpa_t)value << 32);
 			vcpu->arch.sta.shmem |= lo;
-		} else if (reg_val != 0) {
+		} else if (value != 0) {
 			return -EINVAL;
 		}
 		break;
 	default:
-		return -EINVAL;
+		return -ENOENT;
 	}
 
 	return 0;
 }
+
+const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_sta = {
+	.extid_start = SBI_EXT_STA,
+	.extid_end = SBI_EXT_STA,
+	.handler = kvm_sbi_ext_sta_handler,
+	.probe = kvm_sbi_ext_sta_probe,
+	.reset = kvm_riscv_vcpu_sbi_sta_reset,
+	.state_reg_subtype = KVM_REG_RISCV_SBI_STA,
+	.get_state_reg_count = kvm_sbi_ext_sta_get_state_reg_count,
+	.get_state_reg = kvm_sbi_ext_sta_get_reg,
+	.set_state_reg = kvm_sbi_ext_sta_set_reg,
+};
-- 
2.43.0

[PATCH v3 4/6] RISC-V: KVM: Move copy_sbi_ext_reg_indices() to SBI implementation

[Anup Patel]

The ONE_REG handling of SBI extension enable/disable registers and
SBI extension state registers is already under SBI implementation.
On similar lines, let's move copy_sbi_ext_reg_indices() under SBI
implementation.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
---
 arch/riscv/include/asm/kvm_vcpu_sbi.h |  2 +-
 arch/riscv/kvm/vcpu_onereg.c          | 29 ++-------------------------
 arch/riscv/kvm/vcpu_sbi.c             | 27 ++++++++++++++++++++++++-
 3 files changed, 29 insertions(+), 29 deletions(-)

diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h
index 8970cc7530c4..d75ca45c0152 100644
--- a/arch/riscv/include/asm/kvm_vcpu_sbi.h
+++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h
@@ -77,6 +77,7 @@ void kvm_riscv_vcpu_sbi_request_reset(struct kvm_vcpu *vcpu,
 				      unsigned long pc, unsigned long a1);
 void kvm_riscv_vcpu_sbi_load_reset_state(struct kvm_vcpu *vcpu);
 int kvm_riscv_vcpu_sbi_return(struct kvm_vcpu *vcpu, struct kvm_run *run);
+int kvm_riscv_vcpu_reg_indices_sbi_ext(struct kvm_vcpu *vcpu, u64 __user *uindices);
 int kvm_riscv_vcpu_set_reg_sbi_ext(struct kvm_vcpu *vcpu,
 				   const struct kvm_one_reg *reg);
 int kvm_riscv_vcpu_get_reg_sbi_ext(struct kvm_vcpu *vcpu,
@@ -86,7 +87,6 @@ int kvm_riscv_vcpu_set_reg_sbi(struct kvm_vcpu *vcpu, const struct kvm_one_reg *
 int kvm_riscv_vcpu_get_reg_sbi(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
 const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext(
 				struct kvm_vcpu *vcpu, unsigned long extid);
-bool riscv_vcpu_supports_sbi_ext(struct kvm_vcpu *vcpu, int idx);
 int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run);
 void kvm_riscv_vcpu_sbi_init(struct kvm_vcpu *vcpu);
 void kvm_riscv_vcpu_sbi_deinit(struct kvm_vcpu *vcpu);
diff --git a/arch/riscv/kvm/vcpu_onereg.c b/arch/riscv/kvm/vcpu_onereg.c
index 0f4e444e5e10..865dae903aa0 100644
--- a/arch/riscv/kvm/vcpu_onereg.c
+++ b/arch/riscv/kvm/vcpu_onereg.c
@@ -1082,34 +1082,9 @@ static inline unsigned long num_isa_ext_regs(const struct kvm_vcpu *vcpu)
 	return copy_isa_ext_reg_indices(vcpu, NULL);
 }
 
-static int copy_sbi_ext_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
-{
-	unsigned int n = 0;
-
-	for (int i = 0; i < KVM_RISCV_SBI_EXT_MAX; i++) {
-		u64 size = IS_ENABLED(CONFIG_32BIT) ?
-			   KVM_REG_SIZE_U32 : KVM_REG_SIZE_U64;
-		u64 reg = KVM_REG_RISCV | size | KVM_REG_RISCV_SBI_EXT |
-			  KVM_REG_RISCV_SBI_SINGLE | i;
-
-		if (!riscv_vcpu_supports_sbi_ext(vcpu, i))
-			continue;
-
-		if (uindices) {
-			if (put_user(reg, uindices))
-				return -EFAULT;
-			uindices++;
-		}
-
-		n++;
-	}
-
-	return n;
-}
-
 static unsigned long num_sbi_ext_regs(struct kvm_vcpu *vcpu)
 {
-	return copy_sbi_ext_reg_indices(vcpu, NULL);
+	return kvm_riscv_vcpu_reg_indices_sbi_ext(vcpu, NULL);
 }
 
 static inline unsigned long num_sbi_regs(struct kvm_vcpu *vcpu)
@@ -1237,7 +1212,7 @@ int kvm_riscv_vcpu_copy_reg_indices(struct kvm_vcpu *vcpu,
 		return ret;
 	uindices += ret;
 
-	ret = copy_sbi_ext_reg_indices(vcpu, uindices);
+	ret = kvm_riscv_vcpu_reg_indices_sbi_ext(vcpu, uindices);
 	if (ret < 0)
 		return ret;
 	uindices += ret;
diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c
index 04903e5012d6..1b13623380e1 100644
--- a/arch/riscv/kvm/vcpu_sbi.c
+++ b/arch/riscv/kvm/vcpu_sbi.c
@@ -110,7 +110,7 @@ riscv_vcpu_get_sbi_ext(struct kvm_vcpu *vcpu, unsigned long idx)
 	return sext;
 }
 
-bool riscv_vcpu_supports_sbi_ext(struct kvm_vcpu *vcpu, int idx)
+static bool riscv_vcpu_supports_sbi_ext(struct kvm_vcpu *vcpu, int idx)
 {
 	struct kvm_vcpu_sbi_context *scontext = &vcpu->arch.sbi_context;
 	const struct kvm_riscv_sbi_extension_entry *sext;
@@ -288,6 +288,31 @@ static int riscv_vcpu_get_sbi_ext_multi(struct kvm_vcpu *vcpu,
 	return 0;
 }
 
+int kvm_riscv_vcpu_reg_indices_sbi_ext(struct kvm_vcpu *vcpu, u64 __user *uindices)
+{
+	unsigned int n = 0;
+
+	for (int i = 0; i < KVM_RISCV_SBI_EXT_MAX; i++) {
+		u64 size = IS_ENABLED(CONFIG_32BIT) ?
+			   KVM_REG_SIZE_U32 : KVM_REG_SIZE_U64;
+		u64 reg = KVM_REG_RISCV | size | KVM_REG_RISCV_SBI_EXT |
+			  KVM_REG_RISCV_SBI_SINGLE | i;
+
+		if (!riscv_vcpu_supports_sbi_ext(vcpu, i))
+			continue;
+
+		if (uindices) {
+			if (put_user(reg, uindices))
+				return -EFAULT;
+			uindices++;
+		}
+
+		n++;
+	}
+
+	return n;
+}
+
 int kvm_riscv_vcpu_set_reg_sbi_ext(struct kvm_vcpu *vcpu,
 				   const struct kvm_one_reg *reg)
 {
-- 
2.43.0

[PATCH v3 5/6] RISC-V: KVM: Implement ONE_REG interface for SBI FWFT state

[Anup Patel]

The KVM user-space needs a way to save/restore the state of
SBI FWFT features so implement SBI extension ONE_REG callbacks.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 arch/riscv/include/asm/kvm_vcpu_sbi_fwft.h |   1 +
 arch/riscv/include/uapi/asm/kvm.h          |  15 ++
 arch/riscv/kvm/vcpu_sbi_fwft.c             | 197 +++++++++++++++++++--
 3 files changed, 200 insertions(+), 13 deletions(-)

diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi_fwft.h b/arch/riscv/include/asm/kvm_vcpu_sbi_fwft.h
index afb6305e46bb..5604cec79902 100644
--- a/arch/riscv/include/asm/kvm_vcpu_sbi_fwft.h
+++ b/arch/riscv/include/asm/kvm_vcpu_sbi_fwft.h
@@ -16,6 +16,7 @@ struct kvm_sbi_fwft_feature;
 struct kvm_sbi_fwft_config {
 	const struct kvm_sbi_fwft_feature *feature;
 	bool supported;
+	bool enabled;
 	unsigned long flags;
 };
 
diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h
index d2ebc4d0be4b..11fe4a89600c 100644
--- a/arch/riscv/include/uapi/asm/kvm.h
+++ b/arch/riscv/include/uapi/asm/kvm.h
@@ -220,6 +220,18 @@ struct kvm_riscv_sbi_sta {
 	unsigned long shmem_hi;
 };
 
+struct kvm_riscv_sbi_fwft_feature {
+	unsigned long enable;
+	unsigned long flags;
+	unsigned long value;
+};
+
+/* SBI FWFT extension registers for KVM_GET_ONE_REG and KVM_SET_ONE_REG */
+struct kvm_riscv_sbi_fwft {
+	struct kvm_riscv_sbi_fwft_feature misaligned_deleg;
+	struct kvm_riscv_sbi_fwft_feature pointer_masking;
+};
+
 /* Possible states for kvm_riscv_timer */
 #define KVM_RISCV_TIMER_STATE_OFF	0
 #define KVM_RISCV_TIMER_STATE_ON	1
@@ -303,6 +315,9 @@ struct kvm_riscv_sbi_sta {
 #define KVM_REG_RISCV_SBI_STA		(0x0 << KVM_REG_RISCV_SUBTYPE_SHIFT)
 #define KVM_REG_RISCV_SBI_STA_REG(name)		\
 		(offsetof(struct kvm_riscv_sbi_sta, name) / sizeof(unsigned long))
+#define KVM_REG_RISCV_SBI_FWFT		(0x1 << KVM_REG_RISCV_SUBTYPE_SHIFT)
+#define KVM_REG_RISCV_SBI_FWFT_REG(name)	\
+		(offsetof(struct kvm_riscv_sbi_fwft, name) / sizeof(unsigned long))
 
 /* Device Control API: RISC-V AIA */
 #define KVM_DEV_RISCV_APLIC_ALIGN		0x1000
diff --git a/arch/riscv/kvm/vcpu_sbi_fwft.c b/arch/riscv/kvm/vcpu_sbi_fwft.c
index 5a3bad0f9330..cacb3d4410a5 100644
--- a/arch/riscv/kvm/vcpu_sbi_fwft.c
+++ b/arch/riscv/kvm/vcpu_sbi_fwft.c
@@ -22,6 +22,11 @@ struct kvm_sbi_fwft_feature {
 	 */
 	enum sbi_fwft_feature_t id;
 
+	/**
+	 * @first_reg_num: ONE_REG index of the first ONE_REG register
+	 */
+	unsigned long first_reg_num;
+
 	/**
 	 * @supported: Check if the feature is supported on the vcpu
 	 *
@@ -44,7 +49,8 @@ struct kvm_sbi_fwft_feature {
 	 *
 	 * This callback is mandatory
 	 */
-	long (*set)(struct kvm_vcpu *vcpu, struct kvm_sbi_fwft_config *conf, unsigned long value);
+	long (*set)(struct kvm_vcpu *vcpu, struct kvm_sbi_fwft_config *conf,
+		    bool one_reg_access, unsigned long value);
 
 	/**
 	 * @get: Get the feature current value
@@ -53,7 +59,8 @@ struct kvm_sbi_fwft_feature {
 	 *
 	 * This callback is mandatory
 	 */
-	long (*get)(struct kvm_vcpu *vcpu, struct kvm_sbi_fwft_config *conf, unsigned long *value);
+	long (*get)(struct kvm_vcpu *vcpu, struct kvm_sbi_fwft_config *conf,
+		    bool one_reg_access, unsigned long *value);
 };
 
 static const enum sbi_fwft_feature_t kvm_fwft_defined_features[] = {
@@ -91,16 +98,18 @@ static void kvm_sbi_fwft_reset_misaligned_delegation(struct kvm_vcpu *vcpu)
 
 static long kvm_sbi_fwft_set_misaligned_delegation(struct kvm_vcpu *vcpu,
 					struct kvm_sbi_fwft_config *conf,
-					unsigned long value)
+					bool one_reg_access, unsigned long value)
 {
 	struct kvm_vcpu_config *cfg = &vcpu->arch.cfg;
 
 	if (value == 1) {
 		cfg->hedeleg |= MIS_DELEG;
-		csr_set(CSR_HEDELEG, MIS_DELEG);
+		if (!one_reg_access)
+			csr_set(CSR_HEDELEG, MIS_DELEG);
 	} else if (value == 0) {
 		cfg->hedeleg &= ~MIS_DELEG;
-		csr_clear(CSR_HEDELEG, MIS_DELEG);
+		if (!one_reg_access)
+			csr_clear(CSR_HEDELEG, MIS_DELEG);
 	} else {
 		return SBI_ERR_INVALID_PARAM;
 	}
@@ -110,10 +119,11 @@ static long kvm_sbi_fwft_set_misaligned_delegation(struct kvm_vcpu *vcpu,
 
 static long kvm_sbi_fwft_get_misaligned_delegation(struct kvm_vcpu *vcpu,
 					struct kvm_sbi_fwft_config *conf,
-					unsigned long *value)
+					bool one_reg_access, unsigned long *value)
 {
-	*value = (csr_read(CSR_HEDELEG) & MIS_DELEG) == MIS_DELEG;
+	struct kvm_vcpu_config *cfg = &vcpu->arch.cfg;
 
+	*value = (cfg->hedeleg & MIS_DELEG) == MIS_DELEG;
 	return SBI_SUCCESS;
 }
 
@@ -145,7 +155,7 @@ static void kvm_sbi_fwft_reset_pointer_masking_pmlen(struct kvm_vcpu *vcpu)
 
 static long kvm_sbi_fwft_set_pointer_masking_pmlen(struct kvm_vcpu *vcpu,
 						   struct kvm_sbi_fwft_config *conf,
-						   unsigned long value)
+						   bool one_reg_access, unsigned long value)
 {
 	struct kvm_sbi_fwft *fwft = vcpu_to_fwft(vcpu);
 	unsigned long pmm;
@@ -167,14 +177,15 @@ static long kvm_sbi_fwft_set_pointer_masking_pmlen(struct kvm_vcpu *vcpu,
 	 * update here so that VCPU see's pointer masking mode change
 	 * immediately.
 	 */
-	csr_write(CSR_HENVCFG, vcpu->arch.cfg.henvcfg);
+	if (!one_reg_access)
+		csr_write(CSR_HENVCFG, vcpu->arch.cfg.henvcfg);
 
 	return SBI_SUCCESS;
 }
 
 static long kvm_sbi_fwft_get_pointer_masking_pmlen(struct kvm_vcpu *vcpu,
 						   struct kvm_sbi_fwft_config *conf,
-						   unsigned long *value)
+						   bool one_reg_access, unsigned long *value)
 {
 	switch (vcpu->arch.cfg.henvcfg & ENVCFG_PMM) {
 	case ENVCFG_PMM_PMLEN_0:
@@ -198,6 +209,8 @@ static long kvm_sbi_fwft_get_pointer_masking_pmlen(struct kvm_vcpu *vcpu,
 static const struct kvm_sbi_fwft_feature features[] = {
 	{
 		.id = SBI_FWFT_MISALIGNED_EXC_DELEG,
+		.first_reg_num = offsetof(struct kvm_riscv_sbi_fwft, misaligned_deleg.enable) /
+				 sizeof(unsigned long),
 		.supported = kvm_sbi_fwft_misaligned_delegation_supported,
 		.reset = kvm_sbi_fwft_reset_misaligned_delegation,
 		.set = kvm_sbi_fwft_set_misaligned_delegation,
@@ -206,6 +219,8 @@ static const struct kvm_sbi_fwft_feature features[] = {
 #ifndef CONFIG_32BIT
 	{
 		.id = SBI_FWFT_POINTER_MASKING_PMLEN,
+		.first_reg_num = offsetof(struct kvm_riscv_sbi_fwft, pointer_masking.enable) /
+				 sizeof(unsigned long),
 		.supported = kvm_sbi_fwft_pointer_masking_pmlen_supported,
 		.reset = kvm_sbi_fwft_reset_pointer_masking_pmlen,
 		.set = kvm_sbi_fwft_set_pointer_masking_pmlen,
@@ -214,6 +229,20 @@ static const struct kvm_sbi_fwft_feature features[] = {
 #endif
 };
 
+static const struct kvm_sbi_fwft_feature *kvm_sbi_fwft_regnum_to_feature(unsigned long reg_num)
+{
+	const struct kvm_sbi_fwft_feature *feature;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(features); i++) {
+		feature = &features[i];
+		if (feature->first_reg_num <= reg_num && reg_num < (feature->first_reg_num + 3))
+			return feature;
+	}
+
+	return NULL;
+}
+
 static struct kvm_sbi_fwft_config *
 kvm_sbi_fwft_get_config(struct kvm_vcpu *vcpu, enum sbi_fwft_feature_t feature)
 {
@@ -241,7 +270,7 @@ static int kvm_fwft_get_feature(struct kvm_vcpu *vcpu, u32 feature,
 		return SBI_ERR_DENIED;
 	}
 
-	if (!tconf->supported)
+	if (!tconf->supported || !tconf->enabled)
 		return SBI_ERR_NOT_SUPPORTED;
 
 	*conf = tconf;
@@ -267,7 +296,7 @@ static int kvm_sbi_fwft_set(struct kvm_vcpu *vcpu, u32 feature,
 
 	conf->flags = flags;
 
-	return conf->feature->set(vcpu, conf, value);
+	return conf->feature->set(vcpu, conf, false, value);
 }
 
 static int kvm_sbi_fwft_get(struct kvm_vcpu *vcpu, unsigned long feature,
@@ -280,7 +309,7 @@ static int kvm_sbi_fwft_get(struct kvm_vcpu *vcpu, unsigned long feature,
 	if (ret)
 		return ret;
 
-	return conf->feature->get(vcpu, conf, value);
+	return conf->feature->get(vcpu, conf, false, value);
 }
 
 static int kvm_sbi_ext_fwft_handler(struct kvm_vcpu *vcpu, struct kvm_run *run,
@@ -327,6 +356,7 @@ static int kvm_sbi_ext_fwft_init(struct kvm_vcpu *vcpu)
 		else
 			conf->supported = true;
 
+		conf->enabled = conf->supported;
 		conf->feature = feature;
 	}
 
@@ -354,6 +384,142 @@ static void kvm_sbi_ext_fwft_reset(struct kvm_vcpu *vcpu)
 	}
 }
 
+static unsigned long kvm_sbi_ext_fwft_get_reg_count(struct kvm_vcpu *vcpu)
+{
+	unsigned long max_reg_count = sizeof(struct kvm_riscv_sbi_fwft) / sizeof(unsigned long);
+	const struct kvm_sbi_fwft_feature *feature;
+	struct kvm_sbi_fwft_config *conf;
+	unsigned long reg, ret = 0;
+
+	for (reg = 0; reg < max_reg_count; reg++) {
+		feature = kvm_sbi_fwft_regnum_to_feature(reg);
+		if (!feature)
+			continue;
+
+		conf = kvm_sbi_fwft_get_config(vcpu, feature->id);
+		if (!conf || !conf->supported)
+			continue;
+
+		ret++;
+	}
+
+	return ret;
+}
+
+static int kvm_sbi_ext_fwft_get_reg_id(struct kvm_vcpu *vcpu, int index, u64 *reg_id)
+{
+	int reg, max_reg_count = sizeof(struct kvm_riscv_sbi_fwft) / sizeof(unsigned long);
+	const struct kvm_sbi_fwft_feature *feature;
+	struct kvm_sbi_fwft_config *conf;
+	int idx = 0;
+
+	for (reg = 0; reg < max_reg_count; reg++) {
+		feature = kvm_sbi_fwft_regnum_to_feature(reg);
+		if (!feature)
+			continue;
+
+		conf = kvm_sbi_fwft_get_config(vcpu, feature->id);
+		if (!conf || !conf->supported)
+			continue;
+
+		if (index == idx) {
+			*reg_id = KVM_REG_RISCV |
+				  (IS_ENABLED(CONFIG_32BIT) ?
+				   KVM_REG_SIZE_U32 : KVM_REG_SIZE_U64) |
+				  KVM_REG_RISCV_SBI_STATE |
+				  KVM_REG_RISCV_SBI_FWFT | reg;
+			return 0;
+		}
+
+		idx++;
+	}
+
+	return -ENOENT;
+}
+
+static int kvm_sbi_ext_fwft_get_reg(struct kvm_vcpu *vcpu, unsigned long reg_num,
+				    unsigned long reg_size, void *reg_val)
+{
+	const struct kvm_sbi_fwft_feature *feature;
+	struct kvm_sbi_fwft_config *conf;
+	unsigned long *value;
+	int ret = 0;
+
+	if (reg_size != sizeof(unsigned long))
+		return -EINVAL;
+	value = reg_val;
+
+	feature = kvm_sbi_fwft_regnum_to_feature(reg_num);
+	if (!feature)
+		return -ENOENT;
+
+	conf = kvm_sbi_fwft_get_config(vcpu, feature->id);
+	if (!conf || !conf->supported)
+		return -ENOENT;
+
+	switch (reg_num - feature->first_reg_num) {
+	case 0:
+		*value = conf->enabled;
+		break;
+	case 1:
+		*value = conf->flags;
+		break;
+	case 2:
+		ret = conf->feature->get(vcpu, conf, true, value);
+		break;
+	default:
+		return -ENOENT;
+	}
+
+	return sbi_err_map_linux_errno(ret);
+}
+
+static int kvm_sbi_ext_fwft_set_reg(struct kvm_vcpu *vcpu, unsigned long reg_num,
+				    unsigned long reg_size, const void *reg_val)
+{
+	const struct kvm_sbi_fwft_feature *feature;
+	struct kvm_sbi_fwft_config *conf;
+	unsigned long value;
+	int ret = 0;
+
+	if (reg_size != sizeof(unsigned long))
+		return -EINVAL;
+	value = *(const unsigned long *)reg_val;
+
+	feature = kvm_sbi_fwft_regnum_to_feature(reg_num);
+	if (!feature)
+		return -ENOENT;
+
+	conf = kvm_sbi_fwft_get_config(vcpu, feature->id);
+	if (!conf || !conf->supported)
+		return -ENOENT;
+
+	switch (reg_num - feature->first_reg_num) {
+	case 0:
+		switch (value) {
+		case 0:
+			conf->enabled = false;
+			break;
+		case 1:
+			conf->enabled = true;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+	case 1:
+		conf->flags = value & SBI_FWFT_SET_FLAG_LOCK;
+		break;
+	case 2:
+		ret = conf->feature->set(vcpu, conf, true, value);
+		break;
+	default:
+		return -ENOENT;
+	}
+
+	return sbi_err_map_linux_errno(ret);
+}
+
 const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_fwft = {
 	.extid_start = SBI_EXT_FWFT,
 	.extid_end = SBI_EXT_FWFT,
@@ -361,4 +527,9 @@ const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_fwft = {
 	.init = kvm_sbi_ext_fwft_init,
 	.deinit = kvm_sbi_ext_fwft_deinit,
 	.reset = kvm_sbi_ext_fwft_reset,
+	.state_reg_subtype = KVM_REG_RISCV_SBI_FWFT,
+	.get_state_reg_count = kvm_sbi_ext_fwft_get_reg_count,
+	.get_state_reg_id = kvm_sbi_ext_fwft_get_reg_id,
+	.get_state_reg = kvm_sbi_ext_fwft_get_reg,
+	.set_state_reg = kvm_sbi_ext_fwft_set_reg,
 };
-- 
2.43.0

[PATCH v3 6/6] KVM: riscv: selftests: Add SBI FWFT to get-reg-list test

[Anup Patel]

KVM RISC-V now supports SBI FWFT, so add it to the get-reg-list test.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
 .../selftests/kvm/riscv/get-reg-list.c        | 32 +++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/tools/testing/selftests/kvm/riscv/get-reg-list.c b/tools/testing/selftests/kvm/riscv/get-reg-list.c
index 34456e8cba02..705ab3d7778b 100644
--- a/tools/testing/selftests/kvm/riscv/get-reg-list.c
+++ b/tools/testing/selftests/kvm/riscv/get-reg-list.c
@@ -132,6 +132,7 @@ bool filter_reg(__u64 reg)
 	case KVM_REG_RISCV_SBI_EXT | KVM_REG_RISCV_SBI_SINGLE | KVM_RISCV_SBI_EXT_DBCN:
 	case KVM_REG_RISCV_SBI_EXT | KVM_REG_RISCV_SBI_SINGLE | KVM_RISCV_SBI_EXT_SUSP:
 	case KVM_REG_RISCV_SBI_EXT | KVM_REG_RISCV_SBI_SINGLE | KVM_RISCV_SBI_EXT_STA:
+	case KVM_REG_RISCV_SBI_EXT | KVM_REG_RISCV_SBI_SINGLE | KVM_RISCV_SBI_EXT_FWFT:
 	case KVM_REG_RISCV_SBI_EXT | KVM_REG_RISCV_SBI_SINGLE | KVM_RISCV_SBI_EXT_EXPERIMENTAL:
 	case KVM_REG_RISCV_SBI_EXT | KVM_REG_RISCV_SBI_SINGLE | KVM_RISCV_SBI_EXT_VENDOR:
 		return true;
@@ -637,6 +638,7 @@ static const char *sbi_ext_single_id_to_str(__u64 reg_off)
 		KVM_SBI_EXT_ARR(KVM_RISCV_SBI_EXT_DBCN),
 		KVM_SBI_EXT_ARR(KVM_RISCV_SBI_EXT_SUSP),
 		KVM_SBI_EXT_ARR(KVM_RISCV_SBI_EXT_STA),
+		KVM_SBI_EXT_ARR(KVM_RISCV_SBI_EXT_FWFT),
 		KVM_SBI_EXT_ARR(KVM_RISCV_SBI_EXT_EXPERIMENTAL),
 		KVM_SBI_EXT_ARR(KVM_RISCV_SBI_EXT_VENDOR),
 	};
@@ -693,6 +695,19 @@ static const char *sbi_sta_id_to_str(__u64 reg_off)
 	return strdup_printf("KVM_REG_RISCV_SBI_STA | %lld /* UNKNOWN */", reg_off);
 }
 
+static const char *sbi_fwft_id_to_str(__u64 reg_off)
+{
+	switch (reg_off) {
+	case 0: return "KVM_REG_RISCV_SBI_FWFT | KVM_REG_RISCV_SBI_FWFT_REG(misaligned_deleg.enable)";
+	case 1: return "KVM_REG_RISCV_SBI_FWFT | KVM_REG_RISCV_SBI_FWFT_REG(misaligned_deleg.flags)";
+	case 2: return "KVM_REG_RISCV_SBI_FWFT | KVM_REG_RISCV_SBI_FWFT_REG(misaligned_deleg.value)";
+	case 3: return "KVM_REG_RISCV_SBI_FWFT | KVM_REG_RISCV_SBI_FWFT_REG(pointer_masking.enable)";
+	case 4: return "KVM_REG_RISCV_SBI_FWFT | KVM_REG_RISCV_SBI_FWFT_REG(pointer_masking.flags)";
+	case 5: return "KVM_REG_RISCV_SBI_FWFT | KVM_REG_RISCV_SBI_FWFT_REG(pointer_masking.value)";
+	}
+	return strdup_printf("KVM_REG_RISCV_SBI_FWFT | %lld /* UNKNOWN */", reg_off);
+}
+
 static const char *sbi_id_to_str(const char *prefix, __u64 id)
 {
 	__u64 reg_off = id & ~(REG_MASK | KVM_REG_RISCV_SBI_STATE);
@@ -705,6 +720,8 @@ static const char *sbi_id_to_str(const char *prefix, __u64 id)
 	switch (reg_subtype) {
 	case KVM_REG_RISCV_SBI_STA:
 		return sbi_sta_id_to_str(reg_off);
+	case KVM_REG_RISCV_SBI_FWFT:
+		return sbi_fwft_id_to_str(reg_off);
 	}
 
 	return strdup_printf("%lld | %lld /* UNKNOWN */", reg_subtype, reg_off);
@@ -872,6 +889,16 @@ static __u64 sbi_sta_regs[] = {
 	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_SBI_STATE | KVM_REG_RISCV_SBI_STA | KVM_REG_RISCV_SBI_STA_REG(shmem_hi),
 };
 
+static __u64 sbi_fwft_regs[] = {
+	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_SBI_EXT | KVM_REG_RISCV_SBI_SINGLE | KVM_RISCV_SBI_EXT_FWFT,
+	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_SBI_STATE | KVM_REG_RISCV_SBI_FWFT | KVM_REG_RISCV_SBI_FWFT_REG(misaligned_deleg.enable),
+	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_SBI_STATE | KVM_REG_RISCV_SBI_FWFT | KVM_REG_RISCV_SBI_FWFT_REG(misaligned_deleg.flags),
+	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_SBI_STATE | KVM_REG_RISCV_SBI_FWFT | KVM_REG_RISCV_SBI_FWFT_REG(misaligned_deleg.value),
+	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_SBI_STATE | KVM_REG_RISCV_SBI_FWFT | KVM_REG_RISCV_SBI_FWFT_REG(pointer_masking.enable),
+	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_SBI_STATE | KVM_REG_RISCV_SBI_FWFT | KVM_REG_RISCV_SBI_FWFT_REG(pointer_masking.flags),
+	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_SBI_STATE | KVM_REG_RISCV_SBI_FWFT | KVM_REG_RISCV_SBI_FWFT_REG(pointer_masking.value),
+};
+
 static __u64 zicbom_regs[] = {
 	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_CONFIG | KVM_REG_RISCV_CONFIG_REG(zicbom_block_size),
 	KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_ZICBOM,
@@ -1028,6 +1055,9 @@ static __u64 vector_regs[] = {
 #define SUBLIST_SBI_STA \
 	{"sbi-sta", .feature_type = VCPU_FEATURE_SBI_EXT, .feature = KVM_RISCV_SBI_EXT_STA, \
 	 .regs = sbi_sta_regs, .regs_n = ARRAY_SIZE(sbi_sta_regs),}
+#define SUBLIST_SBI_FWFT \
+	{"sbi-fwft", .feature_type = VCPU_FEATURE_SBI_EXT, .feature = KVM_RISCV_SBI_EXT_FWFT, \
+	 .regs = sbi_fwft_regs, .regs_n = ARRAY_SIZE(sbi_fwft_regs),}
 #define SUBLIST_ZICBOM \
 	{"zicbom", .feature = KVM_RISCV_ISA_EXT_ZICBOM, .regs = zicbom_regs, .regs_n = ARRAY_SIZE(zicbom_regs),}
 #define SUBLIST_ZICBOP \
@@ -1112,6 +1142,7 @@ KVM_SBI_EXT_SUBLIST_CONFIG(sta, STA);
 KVM_SBI_EXT_SIMPLE_CONFIG(pmu, PMU);
 KVM_SBI_EXT_SIMPLE_CONFIG(dbcn, DBCN);
 KVM_SBI_EXT_SIMPLE_CONFIG(susp, SUSP);
+KVM_SBI_EXT_SUBLIST_CONFIG(fwft, FWFT);
 
 KVM_ISA_EXT_SUBLIST_CONFIG(aia, AIA);
 KVM_ISA_EXT_SUBLIST_CONFIG(fp_f, FP_F);
@@ -1191,6 +1222,7 @@ struct vcpu_reg_list *vcpu_configs[] = {
 	&config_sbi_pmu,
 	&config_sbi_dbcn,
 	&config_sbi_susp,
+	&config_sbi_fwft,
 	&config_aia,
 	&config_fp_f,
 	&config_fp_d,
-- 
2.43.0

Re: [PATCH v3 6/6] KVM: riscv: selftests: Add SBI FWFT to get-reg-list test

[Andrew Jones]

On Sat, Aug 23, 2025 at 09:29:47PM +0530, Anup Patel wrote:
> KVM RISC-V now supports SBI FWFT, so add it to the get-reg-list test.
> 
> Signed-off-by: Anup Patel <apatel@ventanamicro.com>
> ---
>  .../selftests/kvm/riscv/get-reg-list.c        | 32 +++++++++++++++++++
>  1 file changed, 32 insertions(+)
>

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>