From: Anup Patel <anup.patel@wdc.com>
To: Palmer Dabbelt <palmer@dabbelt.com>,
Palmer Dabbelt <palmerdabbelt@google.com>,
Paul Walmsley <paul.walmsley@sifive.com>,
Albert Ou <aou@eecs.berkeley.edu>,
Paolo Bonzini <pbonzini@redhat.com>,
Jonathan Corbet <corbet@lwn.net>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alexander Graf <graf@amazon.com>,
Atish Patra <atish.patra@wdc.com>,
Alistair Francis <Alistair.Francis@wdc.com>,
Damien Le Moal <damien.lemoal@wdc.com>,
Anup Patel <anup@brainfault.org>,
kvm@vger.kernel.org, kvm-riscv@lists.infradead.org,
linux-riscv@lists.infradead.org, linux-doc@vger.kernel.org,
linux-kernel@vger.kernel.org, linux-staging@lists.linux.dev,
Anup Patel <anup.patel@wdc.com>
Subject: [PATCH v18 05/18] RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls
Date: Wed, 19 May 2021 09:05:40 +0530 [thread overview]
Message-ID: <20210519033553.1110536-6-anup.patel@wdc.com> (raw)
In-Reply-To: <20210519033553.1110536-1-anup.patel@wdc.com>
For KVM RISC-V, we use KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls to access
VCPU config and registers from user-space.
We have three types of VCPU registers:
1. CONFIG - these are VCPU config and capabilities
2. CORE - these are VCPU general purpose registers
3. CSR - these are VCPU control and status registers
The CONFIG register available to user-space is ISA. The ISA register is
a read and write register where user-space can only write the desired
VCPU ISA capabilities before running the VCPU.
The CORE registers available to user-space are PC, RA, SP, GP, TP, A0-A7,
T0-T6, S0-S11 and MODE. Most of these are RISC-V general registers except
PC and MODE. The PC register represents program counter whereas the MODE
register represent VCPU privilege mode (i.e. S/U-mode).
The CSRs available to user-space are SSTATUS, SIE, STVEC, SSCRATCH, SEPC,
SCAUSE, STVAL, SIP, and SATP. All of these are read/write registers.
In future, more VCPU register types will be added (such as FP) for the
KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/riscv/include/uapi/asm/kvm.h | 53 ++++++-
arch/riscv/kvm/vcpu.c | 246 +++++++++++++++++++++++++++++-
2 files changed, 295 insertions(+), 4 deletions(-)
diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h
index 3d3d703713c6..f7e9dc388d54 100644
--- a/arch/riscv/include/uapi/asm/kvm.h
+++ b/arch/riscv/include/uapi/asm/kvm.h
@@ -41,10 +41,61 @@ struct kvm_guest_debug_arch {
struct kvm_sync_regs {
};
-/* dummy definition */
+/* for KVM_GET_SREGS and KVM_SET_SREGS */
struct kvm_sregs {
};
+/* CONFIG registers for KVM_GET_ONE_REG and KVM_SET_ONE_REG */
+struct kvm_riscv_config {
+ unsigned long isa;
+};
+
+/* CORE registers for KVM_GET_ONE_REG and KVM_SET_ONE_REG */
+struct kvm_riscv_core {
+ struct user_regs_struct regs;
+ unsigned long mode;
+};
+
+/* Possible privilege modes for kvm_riscv_core */
+#define KVM_RISCV_MODE_S 1
+#define KVM_RISCV_MODE_U 0
+
+/* CSR registers for KVM_GET_ONE_REG and KVM_SET_ONE_REG */
+struct kvm_riscv_csr {
+ unsigned long sstatus;
+ unsigned long sie;
+ unsigned long stvec;
+ unsigned long sscratch;
+ unsigned long sepc;
+ unsigned long scause;
+ unsigned long stval;
+ unsigned long sip;
+ unsigned long satp;
+ unsigned long scounteren;
+};
+
+#define KVM_REG_SIZE(id) \
+ (1U << (((id) & KVM_REG_SIZE_MASK) >> KVM_REG_SIZE_SHIFT))
+
+/* If you need to interpret the index values, here is the key: */
+#define KVM_REG_RISCV_TYPE_MASK 0x00000000FF000000
+#define KVM_REG_RISCV_TYPE_SHIFT 24
+
+/* Config registers are mapped as type 1 */
+#define KVM_REG_RISCV_CONFIG (0x01 << KVM_REG_RISCV_TYPE_SHIFT)
+#define KVM_REG_RISCV_CONFIG_REG(name) \
+ (offsetof(struct kvm_riscv_config, name) / sizeof(unsigned long))
+
+/* Core registers are mapped as type 2 */
+#define KVM_REG_RISCV_CORE (0x02 << KVM_REG_RISCV_TYPE_SHIFT)
+#define KVM_REG_RISCV_CORE_REG(name) \
+ (offsetof(struct kvm_riscv_core, name) / sizeof(unsigned long))
+
+/* Control and status registers are mapped as type 3 */
+#define KVM_REG_RISCV_CSR (0x03 << KVM_REG_RISCV_TYPE_SHIFT)
+#define KVM_REG_RISCV_CSR_REG(name) \
+ (offsetof(struct kvm_riscv_csr, name) / sizeof(unsigned long))
+
#endif
#endif /* __LINUX_KVM_RISCV_H */
diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c
index 1c3c3bd72df9..1df21f9a0d6a 100644
--- a/arch/riscv/kvm/vcpu.c
+++ b/arch/riscv/kvm/vcpu.c
@@ -18,7 +18,6 @@
#include <linux/fs.h>
#include <linux/kvm_host.h>
#include <asm/kvm_csr.h>
-#include <asm/delay.h>
#include <asm/hwcap.h>
struct kvm_stats_debugfs_item debugfs_entries[] = {
@@ -133,6 +132,225 @@ vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
return VM_FAULT_SIGBUS;
}
+static int kvm_riscv_vcpu_get_reg_config(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_CONFIG);
+ unsigned long reg_val;
+
+ if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
+ return -EINVAL;
+
+ switch (reg_num) {
+ case KVM_REG_RISCV_CONFIG_REG(isa):
+ reg_val = vcpu->arch.isa;
+ break;
+ default:
+ return -EINVAL;
+ };
+
+ if (copy_to_user(uaddr, ®_val, KVM_REG_SIZE(reg->id)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static int kvm_riscv_vcpu_set_reg_config(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_CONFIG);
+ unsigned long reg_val;
+
+ if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
+ return -EINVAL;
+
+ if (copy_from_user(®_val, uaddr, KVM_REG_SIZE(reg->id)))
+ return -EFAULT;
+
+ switch (reg_num) {
+ case KVM_REG_RISCV_CONFIG_REG(isa):
+ if (!vcpu->arch.ran_atleast_once) {
+ vcpu->arch.isa = reg_val;
+ vcpu->arch.isa &= riscv_isa_extension_base(NULL);
+ vcpu->arch.isa &= KVM_RISCV_ISA_ALLOWED;
+ } else {
+ return -EOPNOTSUPP;
+ }
+ break;
+ default:
+ return -EINVAL;
+ };
+
+ return 0;
+}
+
+static int kvm_riscv_vcpu_get_reg_core(struct kvm_vcpu *vcpu,
+ const struct kvm_one_reg *reg)
+{
+ struct kvm_cpu_context *cntx = &vcpu->arch.guest_context;
+ 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_CORE);
+ unsigned long reg_val;
+
+ if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
+ return -EINVAL;
+ if (reg_num >= sizeof(struct kvm_riscv_core) / sizeof(unsigned long))
+ return -EINVAL;
+
+ if (reg_num == KVM_REG_RISCV_CORE_REG(regs.pc))
+ reg_val = cntx->sepc;
+ else if (KVM_REG_RISCV_CORE_REG(regs.pc) < reg_num &&
+ reg_num <= KVM_REG_RISCV_CORE_REG(regs.t6))
+ reg_val = ((unsigned long *)cntx)[reg_num];
+ else if (reg_num == KVM_REG_RISCV_CORE_REG(mode))
+ reg_val = (cntx->sstatus & SR_SPP) ?
+ KVM_RISCV_MODE_S : KVM_RISCV_MODE_U;
+ else
+ return -EINVAL;
+
+ if (copy_to_user(uaddr, ®_val, KVM_REG_SIZE(reg->id)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static int kvm_riscv_vcpu_set_reg_core(struct kvm_vcpu *vcpu,
+ const struct kvm_one_reg *reg)
+{
+ struct kvm_cpu_context *cntx = &vcpu->arch.guest_context;
+ 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_CORE);
+ unsigned long reg_val;
+
+ if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
+ return -EINVAL;
+ if (reg_num >= sizeof(struct kvm_riscv_core) / sizeof(unsigned long))
+ return -EINVAL;
+
+ if (copy_from_user(®_val, uaddr, KVM_REG_SIZE(reg->id)))
+ return -EFAULT;
+
+ if (reg_num == KVM_REG_RISCV_CORE_REG(regs.pc))
+ cntx->sepc = reg_val;
+ else if (KVM_REG_RISCV_CORE_REG(regs.pc) < reg_num &&
+ reg_num <= KVM_REG_RISCV_CORE_REG(regs.t6))
+ ((unsigned long *)cntx)[reg_num] = reg_val;
+ else if (reg_num == KVM_REG_RISCV_CORE_REG(mode)) {
+ if (reg_val == KVM_RISCV_MODE_S)
+ cntx->sstatus |= SR_SPP;
+ else
+ cntx->sstatus &= ~SR_SPP;
+ } else
+ return -EINVAL;
+
+ return 0;
+}
+
+static int kvm_riscv_vcpu_get_reg_csr(struct kvm_vcpu *vcpu,
+ const struct kvm_one_reg *reg)
+{
+ struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
+ 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_CSR);
+ unsigned long reg_val;
+
+ if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
+ return -EINVAL;
+ if (reg_num >= sizeof(struct kvm_riscv_csr) / sizeof(unsigned long))
+ return -EINVAL;
+
+ if (reg_num == KVM_REG_RISCV_CSR_REG(sip)) {
+ kvm_riscv_vcpu_flush_interrupts(vcpu);
+ reg_val = csr->hvip >> VSIP_TO_HVIP_SHIFT;
+ reg_val = reg_val & VSIP_VALID_MASK;
+ } else if (reg_num == KVM_REG_RISCV_CSR_REG(sie)) {
+ reg_val = csr->hie >> VSIP_TO_HVIP_SHIFT;
+ reg_val = reg_val & VSIP_VALID_MASK;
+ } else
+ reg_val = ((unsigned long *)csr)[reg_num];
+
+ if (copy_to_user(uaddr, ®_val, KVM_REG_SIZE(reg->id)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static int kvm_riscv_vcpu_set_reg_csr(struct kvm_vcpu *vcpu,
+ const struct kvm_one_reg *reg)
+{
+ struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
+ 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_CSR);
+ unsigned long reg_val;
+
+ if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
+ return -EINVAL;
+ if (reg_num >= sizeof(struct kvm_riscv_csr) / sizeof(unsigned long))
+ return -EINVAL;
+
+ if (copy_from_user(®_val, uaddr, KVM_REG_SIZE(reg->id)))
+ return -EFAULT;
+
+ if (reg_num == KVM_REG_RISCV_CSR_REG(sip) ||
+ reg_num == KVM_REG_RISCV_CSR_REG(sie)) {
+ reg_val = reg_val & VSIP_VALID_MASK;
+ reg_val = reg_val << VSIP_TO_HVIP_SHIFT;
+ }
+
+ ((unsigned long *)csr)[reg_num] = reg_val;
+
+ if (reg_num == KVM_REG_RISCV_CSR_REG(sip))
+ WRITE_ONCE(vcpu->arch.irqs_pending_mask, 0);
+
+ return 0;
+}
+
+static int kvm_riscv_vcpu_set_reg(struct kvm_vcpu *vcpu,
+ const struct kvm_one_reg *reg)
+{
+ if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CONFIG)
+ return kvm_riscv_vcpu_set_reg_config(vcpu, reg);
+ else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CORE)
+ return kvm_riscv_vcpu_set_reg_core(vcpu, reg);
+ else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CSR)
+ return kvm_riscv_vcpu_set_reg_csr(vcpu, reg);
+
+ return -EINVAL;
+}
+
+static int kvm_riscv_vcpu_get_reg(struct kvm_vcpu *vcpu,
+ const struct kvm_one_reg *reg)
+{
+ if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CONFIG)
+ return kvm_riscv_vcpu_get_reg_config(vcpu, reg);
+ else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CORE)
+ return kvm_riscv_vcpu_get_reg_core(vcpu, reg);
+ else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CSR)
+ return kvm_riscv_vcpu_get_reg_csr(vcpu, reg);
+
+ return -EINVAL;
+}
+
long kvm_arch_vcpu_async_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
@@ -157,8 +375,30 @@ long kvm_arch_vcpu_async_ioctl(struct file *filp,
long kvm_arch_vcpu_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
- /* TODO: */
- return -EINVAL;
+ struct kvm_vcpu *vcpu = filp->private_data;
+ void __user *argp = (void __user *)arg;
+ long r = -EINVAL;
+
+ switch (ioctl) {
+ case KVM_SET_ONE_REG:
+ case KVM_GET_ONE_REG: {
+ struct kvm_one_reg reg;
+
+ r = -EFAULT;
+ if (copy_from_user(®, argp, sizeof(reg)))
+ break;
+
+ if (ioctl == KVM_SET_ONE_REG)
+ r = kvm_riscv_vcpu_set_reg(vcpu, ®);
+ else
+ r = kvm_riscv_vcpu_get_reg(vcpu, ®);
+ break;
+ }
+ default:
+ break;
+ }
+
+ return r;
}
int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
--
2.25.1
next prev parent reply other threads:[~2021-05-19 3:36 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-19 3:35 [PATCH v18 00/18] KVM RISC-V Support Anup Patel
2021-05-19 3:35 ` [PATCH v18 01/18] RISC-V: Add hypervisor extension related CSR defines Anup Patel
2021-05-19 3:35 ` [PATCH v18 02/18] RISC-V: Add initial skeletal KVM support Anup Patel
2021-05-19 9:24 ` Dan Carpenter
2021-05-19 10:17 ` Dan Carpenter
2021-05-19 3:35 ` [PATCH v18 03/18] RISC-V: KVM: Implement VCPU create, init and destroy functions Anup Patel
2021-05-19 3:35 ` [PATCH v18 04/18] RISC-V: KVM: Implement VCPU interrupts and requests handling Anup Patel
2021-05-19 3:35 ` Anup Patel [this message]
2021-05-19 3:35 ` [PATCH v18 06/18] RISC-V: KVM: Implement VCPU world-switch Anup Patel
2021-05-19 3:35 ` [PATCH v18 07/18] RISC-V: KVM: Handle MMIO exits for VCPU Anup Patel
2021-05-19 3:35 ` [PATCH v18 08/18] RISC-V: KVM: Handle WFI " Anup Patel
2021-05-19 3:35 ` [PATCH v18 09/18] RISC-V: KVM: Implement VMID allocator Anup Patel
2021-05-19 3:35 ` [PATCH v18 10/18] RISC-V: KVM: Implement stage2 page table programming Anup Patel
2021-05-19 3:35 ` [PATCH v18 11/18] RISC-V: KVM: Implement MMU notifiers Anup Patel
2021-05-19 10:09 ` Dan Carpenter
2021-05-19 3:35 ` [PATCH v18 12/18] RISC-V: KVM: Add timer functionality Anup Patel
2021-05-19 3:35 ` [PATCH v18 13/18] RISC-V: KVM: FP lazy save/restore Anup Patel
2021-05-19 3:35 ` [PATCH v18 14/18] RISC-V: KVM: Implement ONE REG interface for FP registers Anup Patel
2021-05-19 10:11 ` Dan Carpenter
2021-05-20 6:09 ` Dan Carpenter
2021-05-19 3:35 ` [PATCH v18 15/18] RISC-V: KVM: Add SBI v0.1 support Anup Patel
2021-05-19 3:35 ` [PATCH v18 16/18] RISC-V: KVM: Document RISC-V specific parts of KVM API Anup Patel
2021-05-19 3:35 ` [PATCH v18 17/18] RISC-V: KVM: Move sources to drivers/staging directory Anup Patel
2021-05-19 3:35 ` [PATCH v18 18/18] RISC-V: KVM: Add MAINTAINERS entry Anup Patel
2021-05-19 4:58 ` [PATCH v18 00/18] KVM RISC-V Support Greg Kroah-Hartman
2021-05-19 5:10 ` Anup Patel
2021-05-19 5:21 ` Greg Kroah-Hartman
2021-05-19 10:47 ` Greg Kroah-Hartman
2021-05-19 11:18 ` Paolo Bonzini
2021-05-19 12:23 ` Greg Kroah-Hartman
2021-05-19 13:29 ` Paolo Bonzini
2021-05-19 13:58 ` Greg Kroah-Hartman
2021-05-19 15:08 ` Dan Carpenter
2021-05-19 15:26 ` Paolo Bonzini
2021-05-21 17:13 ` Palmer Dabbelt
2021-05-21 17:21 ` Paolo Bonzini
2021-05-21 17:47 ` Greg KH
2021-05-21 18:08 ` Palmer Dabbelt
2021-05-21 18:25 ` Greg KH
2021-05-21 20:25 ` Paolo Bonzini
2021-05-24 7:09 ` Guo Ren
2021-05-24 22:57 ` Palmer Dabbelt
2021-05-24 23:08 ` Damien Le Moal
2021-05-25 7:37 ` Greg KH
2021-05-25 8:01 ` Damien Le Moal
2021-05-25 8:11 ` Greg KH
2021-05-25 8:24 ` Paolo Bonzini
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