[PATCH v6 07/18] virt: acrn: Introduce an ioctl to set vCPU registers state

shuo.a.liu
2020-12-01T09:40:57Z

A virtual CPU of User VM has different context due to the different
registers state. ACRN userspace needs to set the virtual CPU
registers state (e.g. giving a initial registers state to a virtual
BSP of a User VM).

HSM provides an ioctl ACRN_IOCTL_SET_VCPU_REGS to do the virtual CPU
registers state setting. The ioctl passes the registers state from ACRN
userspace to the hypervisor directly.

Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yu Wang <yu1.wang@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/virt/acrn/hsm.c | 16 ++++++++
drivers/virt/acrn/hypercall.h | 13 +++++++
include/uapi/linux/acrn.h | 69 +++++++++++++++++++++++++++++++++++
3 files changed, 98 insertions(+)

diff --git a/drivers/virt/acrn/hsm.c b/drivers/virt/acrn/hsm.c
index e618ac6aadaf..77c749fe1fc2 100644
--- a/drivers/virt/acrn/hsm.c
+++ b/drivers/virt/acrn/hsm.c
@@ -9,6 +9,7 @@
* Yakui Zhao <yakui.zhao@intel.com>
*/

+#include <linux/io.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/slab.h>
@@ -46,6 +47,7 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd,
{
struct acrn_vm *vm = filp->private_data;
struct acrn_vm_creation *vm_param;
+ struct acrn_vcpu_regs *cpu_regs;
int ret = 0;

if (vm->vmid == ACRN_INVALID_VMID && cmd != ACRN_IOCTL_CREATE_VM) {
@@ -99,6 +101,20 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd,
case ACRN_IOCTL_DESTROY_VM:
ret = acrn_vm_destroy(vm);
break;
+ case ACRN_IOCTL_SET_VCPU_REGS:
+ cpu_regs = memdup_user((void __user *)ioctl_param,
+ sizeof(struct acrn_vcpu_regs));
+ if (IS_ERR(cpu_regs))
+ return PTR_ERR(cpu_regs);
+
+ memset(cpu_regs->reserved, 0, sizeof(cpu_regs->reserved));
+ ret = hcall_set_vcpu_regs(vm->vmid, virt_to_phys(cpu_regs));
+ if (ret < 0)
+ dev_dbg(acrn_dev.this_device,
+ "Failed to set regs state of VM%u!\n",
+ vm->vmid);
+ kfree(cpu_regs);
+ break;
default:
dev_dbg(acrn_dev.this_device, "Unknown IOCTL 0x%x!\n", cmd);
ret = -ENOTTY;
diff --git a/drivers/virt/acrn/hypercall.h b/drivers/virt/acrn/hypercall.h
index 426b66cadb1f..f29cfae08862 100644
--- a/drivers/virt/acrn/hypercall.h
+++ b/drivers/virt/acrn/hypercall.h
@@ -19,6 +19,7 @@
#define HC_START_VM _HC_ID(HC_ID, HC_ID_VM_BASE + 0x02)
#define HC_PAUSE_VM _HC_ID(HC_ID, HC_ID_VM_BASE + 0x03)
#define HC_RESET_VM _HC_ID(HC_ID, HC_ID_VM_BASE + 0x05)
+#define HC_SET_VCPU_REGS _HC_ID(HC_ID, HC_ID_VM_BASE + 0x06)

/**
* hcall_create_vm() - Create a User VM
@@ -75,4 +76,16 @@ static inline long hcall_reset_vm(u64 vmid)
return acrn_hypercall1(HC_RESET_VM, vmid);
}

+/**
+ * hcall_set_vcpu_regs() - Set up registers of virtual CPU of a User VM
+ * @vmid: User VM ID
+ * @regs_state: Service VM GPA of registers state
+ *
+ * Return: 0 on success, <0 on failure
+ */
+static inline long hcall_set_vcpu_regs(u64 vmid, u64 regs_state)
+{
+ return acrn_hypercall2(HC_SET_VCPU_REGS, vmid, regs_state);
+}
+
#endif /* __ACRN_HSM_HYPERCALL_H */
diff --git a/include/uapi/linux/acrn.h b/include/uapi/linux/acrn.h
index e1608b8a50a2..d5d66b93586e 100644
--- a/include/uapi/linux/acrn.h
+++ b/include/uapi/linux/acrn.h
@@ -35,6 +35,73 @@ struct acrn_vm_creation {
__u64 cpu_affinity;
};

+struct acrn_gp_regs {
+ __le64 rax;
+ __le64 rcx;
+ __le64 rdx;
+ __le64 rbx;
+ __le64 rsp;
+ __le64 rbp;
+ __le64 rsi;
+ __le64 rdi;
+ __le64 r8;
+ __le64 r9;
+ __le64 r10;
+ __le64 r11;
+ __le64 r12;
+ __le64 r13;
+ __le64 r14;
+ __le64 r15;
+};
+
+struct acrn_descriptor_ptr {
+ __le16 limit;
+ __le64 base;
+ __le16 reserved[3];
+} __attribute__ ((__packed__));
+
+struct acrn_regs {
+ struct acrn_gp_regs gprs;
+ struct acrn_descriptor_ptr gdt;
+ struct acrn_descriptor_ptr idt;
+
+ __le64 rip;
+ __le64 cs_base;
+ __le64 cr0;
+ __le64 cr4;
+ __le64 cr3;
+ __le64 ia32_efer;
+ __le64 rflags;
+ __le64 reserved_64[4];
+
+ __le32 cs_ar;
+ __le32 cs_limit;
+ __le32 reserved_32[3];
+
+ __le16 cs_sel;
+ __le16 ss_sel;
+ __le16 ds_sel;
+ __le16 es_sel;
+ __le16 fs_sel;
+ __le16 gs_sel;
+ __le16 ldt_sel;
+ __le16 tr_sel;
+};
+
+/**
+ * struct acrn_vcpu_regs - Info of vCPU registers state
+ * @vcpu_id: vCPU ID
+ * @reserved: Reserved and must be 0
+ * @vcpu_regs: vCPU registers state
+ *
+ * This structure will be passed to hypervisor directly.
+ */
+struct acrn_vcpu_regs {
+ __u16 vcpu_id;
+ __u16 reserved[3];
+ struct acrn_regs vcpu_regs;
+};
+
/* The ioctl type, documented in ioctl-number.rst */
#define ACRN_IOCTL_TYPE 0xA2

@@ -51,5 +118,7 @@ struct acrn_vm_creation {
_IO(ACRN_IOCTL_TYPE, 0x13)
#define ACRN_IOCTL_RESET_VM \
_IO(ACRN_IOCTL_TYPE, 0x15)
+#define ACRN_IOCTL_SET_VCPU_REGS \
+ _IOW(ACRN_IOCTL_TYPE, 0x16, struct acrn_vcpu_regs)

#endif /* _UAPI_ACRN_H */
--
2.28.0