1 files changed, 377 insertions, 65 deletions

diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c
index d45e7da3f0d3..72a2ffb8dcd1 100644
--- a/arch/riscv/kvm/vcpu_sbi.c
+++ b/arch/riscv/kvm/vcpu_sbi.c
@@ -12,56 +12,106 @@
 #include <asm/sbi.h>
 #include <asm/kvm_vcpu_sbi.h>
 
-static int kvm_linux_err_map_sbi(int err)
-{
-	switch (err) {
-	case 0:
-		return SBI_SUCCESS;
-	case -EPERM:
-		return SBI_ERR_DENIED;
-	case -EINVAL:
-		return SBI_ERR_INVALID_PARAM;
-	case -EFAULT:
-		return SBI_ERR_INVALID_ADDRESS;
-	case -EOPNOTSUPP:
-		return SBI_ERR_NOT_SUPPORTED;
-	case -EALREADY:
-		return SBI_ERR_ALREADY_AVAILABLE;
-	default:
-		return SBI_ERR_FAILURE;
-	};
-}
-
-#ifdef CONFIG_RISCV_SBI_V01
-extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_v01;
-#else
+#ifndef CONFIG_RISCV_SBI_V01
 static const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_v01 = {
 	.extid_start = -1UL,
 	.extid_end = -1UL,
 	.handler = NULL,
 };
 #endif
-extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_base;
-extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_time;
-extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_ipi;
-extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_rfence;
-extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_srst;
-extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_hsm;
-extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_experimental;
-extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_vendor;
-
-static const struct kvm_vcpu_sbi_extension *sbi_ext[] = {
-	&vcpu_sbi_ext_v01,
-	&vcpu_sbi_ext_base,
-	&vcpu_sbi_ext_time,
-	&vcpu_sbi_ext_ipi,
-	&vcpu_sbi_ext_rfence,
-	&vcpu_sbi_ext_srst,
-	&vcpu_sbi_ext_hsm,
-	&vcpu_sbi_ext_experimental,
-	&vcpu_sbi_ext_vendor,
+
+#ifndef CONFIG_RISCV_PMU_SBI
+static const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_pmu = {
+	.extid_start = -1UL,
+	.extid_end = -1UL,
+	.handler = NULL,
+};
+#endif
+
+struct kvm_riscv_sbi_extension_entry {
+	enum KVM_RISCV_SBI_EXT_ID ext_idx;
+	const struct kvm_vcpu_sbi_extension *ext_ptr;
 };
 
+static const struct kvm_riscv_sbi_extension_entry sbi_ext[] = {
+	{
+		.ext_idx = KVM_RISCV_SBI_EXT_V01,
+		.ext_ptr = &vcpu_sbi_ext_v01,
+	},
+	{
+		.ext_idx = KVM_RISCV_SBI_EXT_MAX, /* Can't be disabled */
+		.ext_ptr = &vcpu_sbi_ext_base,
+	},
+	{
+		.ext_idx = KVM_RISCV_SBI_EXT_TIME,
+		.ext_ptr = &vcpu_sbi_ext_time,
+	},
+	{
+		.ext_idx = KVM_RISCV_SBI_EXT_IPI,
+		.ext_ptr = &vcpu_sbi_ext_ipi,
+	},
+	{
+		.ext_idx = KVM_RISCV_SBI_EXT_RFENCE,
+		.ext_ptr = &vcpu_sbi_ext_rfence,
+	},
+	{
+		.ext_idx = KVM_RISCV_SBI_EXT_SRST,
+		.ext_ptr = &vcpu_sbi_ext_srst,
+	},
+	{
+		.ext_idx = KVM_RISCV_SBI_EXT_HSM,
+		.ext_ptr = &vcpu_sbi_ext_hsm,
+	},
+	{
+		.ext_idx = KVM_RISCV_SBI_EXT_PMU,
+		.ext_ptr = &vcpu_sbi_ext_pmu,
+	},
+	{
+		.ext_idx = KVM_RISCV_SBI_EXT_DBCN,
+		.ext_ptr = &vcpu_sbi_ext_dbcn,
+	},
+	{
+		.ext_idx = KVM_RISCV_SBI_EXT_STA,
+		.ext_ptr = &vcpu_sbi_ext_sta,
+	},
+	{
+		.ext_idx = KVM_RISCV_SBI_EXT_EXPERIMENTAL,
+		.ext_ptr = &vcpu_sbi_ext_experimental,
+	},
+	{
+		.ext_idx = KVM_RISCV_SBI_EXT_VENDOR,
+		.ext_ptr = &vcpu_sbi_ext_vendor,
+	},
+};
+
+static const struct kvm_riscv_sbi_extension_entry *
+riscv_vcpu_get_sbi_ext(struct kvm_vcpu *vcpu, unsigned long idx)
+{
+	const struct kvm_riscv_sbi_extension_entry *sext = NULL;
+
+	if (idx >= KVM_RISCV_SBI_EXT_MAX)
+		return NULL;
+
+	for (int i = 0; i < ARRAY_SIZE(sbi_ext); i++) {
+		if (sbi_ext[i].ext_idx == idx) {
+			sext = &sbi_ext[i];
+			break;
+		}
+	}
+
+	return sext;
+}
+
+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;
+
+	sext = riscv_vcpu_get_sbi_ext(vcpu, idx);
+
+	return sext && scontext->ext_status[sext->ext_idx] != KVM_RISCV_SBI_EXT_STATUS_UNAVAILABLE;
+}
+
 void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, struct kvm_run *run)
 {
 	struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
@@ -118,14 +168,246 @@ int kvm_riscv_vcpu_sbi_return(struct kvm_vcpu *vcpu, struct kvm_run *run)
 	return 0;
 }
 
-const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext(unsigned long extid)
+static int riscv_vcpu_set_sbi_ext_single(struct kvm_vcpu *vcpu,
+					 unsigned long reg_num,
+					 unsigned long reg_val)
+{
+	struct kvm_vcpu_sbi_context *scontext = &vcpu->arch.sbi_context;
+	const struct kvm_riscv_sbi_extension_entry *sext;
+
+	if (reg_val != 1 && reg_val != 0)
+		return -EINVAL;
+
+	sext = riscv_vcpu_get_sbi_ext(vcpu, reg_num);
+	if (!sext || scontext->ext_status[sext->ext_idx] == KVM_RISCV_SBI_EXT_STATUS_UNAVAILABLE)
+		return -ENOENT;
+
+	scontext->ext_status[sext->ext_idx] = (reg_val) ?
+			KVM_RISCV_SBI_EXT_STATUS_ENABLED :
+			KVM_RISCV_SBI_EXT_STATUS_DISABLED;
+
+	return 0;
+}
+
+static int riscv_vcpu_get_sbi_ext_single(struct kvm_vcpu *vcpu,
+					 unsigned long reg_num,
+					 unsigned long *reg_val)
+{
+	struct kvm_vcpu_sbi_context *scontext = &vcpu->arch.sbi_context;
+	const struct kvm_riscv_sbi_extension_entry *sext;
+
+	sext = riscv_vcpu_get_sbi_ext(vcpu, reg_num);
+	if (!sext || scontext->ext_status[sext->ext_idx] == KVM_RISCV_SBI_EXT_STATUS_UNAVAILABLE)
+		return -ENOENT;
+
+	*reg_val = scontext->ext_status[sext->ext_idx] ==
+				KVM_RISCV_SBI_EXT_STATUS_ENABLED;
+
+	return 0;
+}
+
+static int riscv_vcpu_set_sbi_ext_multi(struct kvm_vcpu *vcpu,
+					unsigned long reg_num,
+					unsigned long reg_val, bool enable)
+{
+	unsigned long i, ext_id;
+
+	if (reg_num > KVM_REG_RISCV_SBI_MULTI_REG_LAST)
+		return -ENOENT;
+
+	for_each_set_bit(i, &reg_val, BITS_PER_LONG) {
+		ext_id = i + reg_num * BITS_PER_LONG;
+		if (ext_id >= KVM_RISCV_SBI_EXT_MAX)
+			break;
+
+		riscv_vcpu_set_sbi_ext_single(vcpu, ext_id, enable);
+	}
+
+	return 0;
+}
+
+static int riscv_vcpu_get_sbi_ext_multi(struct kvm_vcpu *vcpu,
+					unsigned long reg_num,
+					unsigned long *reg_val)
+{
+	unsigned long i, ext_id, ext_val;
+
+	if (reg_num > KVM_REG_RISCV_SBI_MULTI_REG_LAST)
+		return -ENOENT;
+
+	for (i = 0; i < BITS_PER_LONG; i++) {
+		ext_id = i + reg_num * BITS_PER_LONG;
+		if (ext_id >= KVM_RISCV_SBI_EXT_MAX)
+			break;
+
+		ext_val = 0;
+		riscv_vcpu_get_sbi_ext_single(vcpu, ext_id, &ext_val);
+		if (ext_val)
+			*reg_val |= KVM_REG_RISCV_SBI_MULTI_MASK(ext_id);
+	}
+
+	return 0;
+}
+
+int kvm_riscv_vcpu_set_reg_sbi_ext(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_EXT);
+	unsigned long reg_val, reg_subtype;
+
+	if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
+		return -EINVAL;
+
+	if (vcpu->arch.ran_atleast_once)
+		return -EBUSY;
+
+	reg_subtype = reg_num & KVM_REG_RISCV_SUBTYPE_MASK;
+	reg_num &= ~KVM_REG_RISCV_SUBTYPE_MASK;
+
+	if (copy_from_user(&reg_val, uaddr, KVM_REG_SIZE(reg->id)))
+		return -EFAULT;
+
+	switch (reg_subtype) {
+	case KVM_REG_RISCV_SBI_SINGLE:
+		return riscv_vcpu_set_sbi_ext_single(vcpu, reg_num, reg_val);
+	case KVM_REG_RISCV_SBI_MULTI_EN:
+		return riscv_vcpu_set_sbi_ext_multi(vcpu, reg_num, reg_val, true);
+	case KVM_REG_RISCV_SBI_MULTI_DIS:
+		return riscv_vcpu_set_sbi_ext_multi(vcpu, reg_num, reg_val, false);
+	default:
+		return -ENOENT;
+	}
+
+	return 0;
+}
+
+int kvm_riscv_vcpu_get_reg_sbi_ext(struct kvm_vcpu *vcpu,
+				   const struct kvm_one_reg *reg)
+{
+	int rc;
+	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_EXT);
+	unsigned long reg_val, reg_subtype;
+
+	if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
+		return -EINVAL;
+
+	reg_subtype = reg_num & KVM_REG_RISCV_SUBTYPE_MASK;
+	reg_num &= ~KVM_REG_RISCV_SUBTYPE_MASK;
+
+	reg_val = 0;
+	switch (reg_subtype) {
+	case KVM_REG_RISCV_SBI_SINGLE:
+		rc = riscv_vcpu_get_sbi_ext_single(vcpu, reg_num, &reg_val);
+		break;
+	case KVM_REG_RISCV_SBI_MULTI_EN:
+	case KVM_REG_RISCV_SBI_MULTI_DIS:
+		rc = riscv_vcpu_get_sbi_ext_multi(vcpu, reg_num, &reg_val);
+		if (!rc && reg_subtype == KVM_REG_RISCV_SBI_MULTI_DIS)
+			reg_val = ~reg_val;
+		break;
+	default:
+		rc = -ENOENT;
+	}
+	if (rc)
+		return rc;
+
+	if (copy_to_user(uaddr, &reg_val, KVM_REG_SIZE(reg->id)))
+		return -EFAULT;
+
+	return 0;
+}
+
+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))
+		return -EINVAL;
+
+	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:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+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;
+	int ret;
+
+	if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
+		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:
+		return -EINVAL;
+	}
+
+	if (ret)
+		return ret;
+
+	if (copy_to_user(uaddr, &reg_val, KVM_REG_SIZE(reg->id)))
+		return -EFAULT;
+
+	return 0;
+}
+
+const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext(
+				struct kvm_vcpu *vcpu, unsigned long extid)
 {
-	int i = 0;
+	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++) {
-		if (sbi_ext[i]->extid_start <= extid &&
-		    sbi_ext[i]->extid_end >= extid)
-			return sbi_ext[i];
+		entry = &sbi_ext[i];
+		ext = entry->ext_ptr;
+
+		if (ext->extid_start <= extid && ext->extid_end >= extid) {
+			if (entry->ext_idx >= KVM_RISCV_SBI_EXT_MAX ||
+			    scontext->ext_status[entry->ext_idx] ==
+						KVM_RISCV_SBI_EXT_STATUS_ENABLED)
+				return ext;
+
+			return NULL;
+		}
 	}
 
 	return NULL;
@@ -135,56 +417,86 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run)
 {
 	int ret = 1;
 	bool next_sepc = true;
-	bool userspace_exit = false;
 	struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
 	const struct kvm_vcpu_sbi_extension *sbi_ext;
-	struct kvm_cpu_trap utrap = { 0 };
-	unsigned long out_val = 0;
+	struct kvm_cpu_trap utrap = {0};
+	struct kvm_vcpu_sbi_return sbi_ret = {
+		.out_val = 0,
+		.err_val = 0,
+		.utrap = &utrap,
+	};
 	bool ext_is_v01 = false;
 
-	sbi_ext = kvm_vcpu_sbi_find_ext(cp->a7);
+	sbi_ext = kvm_vcpu_sbi_find_ext(vcpu, cp->a7);
 	if (sbi_ext && sbi_ext->handler) {
 #ifdef CONFIG_RISCV_SBI_V01
 		if (cp->a7 >= SBI_EXT_0_1_SET_TIMER &&
 		    cp->a7 <= SBI_EXT_0_1_SHUTDOWN)
 			ext_is_v01 = true;
 #endif
-		ret = sbi_ext->handler(vcpu, run, &out_val, &utrap, &userspace_exit);
+		ret = sbi_ext->handler(vcpu, run, &sbi_ret);
 	} else {
 		/* Return error for unsupported SBI calls */
 		cp->a0 = SBI_ERR_NOT_SUPPORTED;
 		goto ecall_done;
 	}
 
+	/*
+	 * When the SBI extension returns a Linux error code, it exits the ioctl
+	 * loop and forwards the error to userspace.
+	 */
+	if (ret < 0) {
+		next_sepc = false;
+		goto ecall_done;
+	}
+
 	/* Handle special error cases i.e trap, exit or userspace forward */
-	if (utrap.scause) {
+	if (sbi_ret.utrap->scause) {
 		/* No need to increment sepc or exit ioctl loop */
 		ret = 1;
-		utrap.sepc = cp->sepc;
-		kvm_riscv_vcpu_trap_redirect(vcpu, &utrap);
+		sbi_ret.utrap->sepc = cp->sepc;
+		kvm_riscv_vcpu_trap_redirect(vcpu, sbi_ret.utrap);
 		next_sepc = false;
 		goto ecall_done;
 	}
 
 	/* Exit ioctl loop or Propagate the error code the guest */
-	if (userspace_exit) {
+	if (sbi_ret.uexit) {
 		next_sepc = false;
 		ret = 0;
 	} else {
-		/**
-		 * SBI extension handler always returns an Linux error code. Convert
-		 * it to the SBI specific error code that can be propagated the SBI
-		 * caller.
-		 */
-		ret = kvm_linux_err_map_sbi(ret);
-		cp->a0 = ret;
+		cp->a0 = sbi_ret.err_val;
 		ret = 1;
 	}
 ecall_done:
 	if (next_sepc)
 		cp->sepc += 4;
-	if (!ext_is_v01)
-		cp->a1 = out_val;
+	/* a1 should only be updated when we continue the ioctl loop */
+	if (!ext_is_v01 && ret == 1)
+		cp->a1 = sbi_ret.out_val;
 
 	return ret;
 }
+
+void kvm_riscv_vcpu_sbi_init(struct kvm_vcpu *vcpu)
+{
+	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->probe && !ext->probe(vcpu)) {
+			scontext->ext_status[entry->ext_idx] =
+				KVM_RISCV_SBI_EXT_STATUS_UNAVAILABLE;
+			continue;
+		}
+
+		scontext->ext_status[entry->ext_idx] = ext->default_disabled ?
+					KVM_RISCV_SBI_EXT_STATUS_DISABLED :
+					KVM_RISCV_SBI_EXT_STATUS_ENABLED;
+	}
+}