[PATCH v4 11/17] virt: acrn: Introduce interfaces for PCI device passthrough

shuo.a.liu
2020-09-22T11:47:56Z

From: Shuo Liu <shuo.a.liu@intel.com>

PCI device passthrough enables an OS in a virtual machine to directly
access a PCI device in the host. It promises almost the native
performance, which is required in performance-critical scenarios of
ACRN.

HSM provides the following ioctls:
- Assign - ACRN_IOCTL_ASSIGN_PCIDEV
Pass data struct acrn_pcidev from userspace to the hypervisor, and
inform the hypervisor to assign a PCI device to a User VM.

- De-assign - ACRN_IOCTL_DEASSIGN_PCIDEV
Pass data struct acrn_pcidev from userspace to the hypervisor, and
inform the hypervisor to de-assign a PCI device from a User VM.

- Set a interrupt of a passthrough device - ACRN_IOCTL_SET_PTDEV_INTR
Pass data struct acrn_ptdev_irq from userspace to the hypervisor,
and inform the hypervisor to map a INTx interrupt of passthrough
device of User VM.

- Reset passthrough device interrupt - ACRN_IOCTL_RESET_PTDEV_INTR
Pass data struct acrn_ptdev_irq from userspace to the hypervisor,
and inform the hypervisor to unmap a INTx interrupt of passthrough
device of User VM.

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 | 50 +++++++++++++++++++++++++++
drivers/virt/acrn/hypercall.h | 54 ++++++++++++++++++++++++++++++
include/uapi/linux/acrn.h | 63 +++++++++++++++++++++++++++++++++++
3 files changed, 167 insertions(+)

diff --git a/drivers/virt/acrn/hsm.c b/drivers/virt/acrn/hsm.c
index b4b5d99ff6bb..bcb5e273dcc3 100644
--- a/drivers/virt/acrn/hsm.c
+++ b/drivers/virt/acrn/hsm.c
@@ -49,7 +49,9 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd,
struct acrn_vm_creation *vm_param;
struct acrn_vcpu_regs *cpu_regs;
struct acrn_ioreq_notify notify;
+ struct acrn_ptdev_irq *irq_info;
struct acrn_vm_memmap memmap;
+ struct acrn_pcidev *pcidev;
int ret = 0;

if (vm->vmid == ACRN_INVALID_VMID && cmd != ACRN_IOCTL_CREATE_VM) {
@@ -128,6 +130,54 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd,

ret = acrn_vm_memseg_unmap(vm, &memmap);
break;
+ case ACRN_IOCTL_ASSIGN_PCIDEV:
+ pcidev = memdup_user((void __user *)ioctl_param,
+ sizeof(struct acrn_pcidev));
+ if (IS_ERR(pcidev))
+ return PTR_ERR(pcidev);
+
+ ret = hcall_assign_pcidev(vm->vmid, virt_to_phys(pcidev));
+ if (ret < 0)
+ dev_err(acrn_dev.this_device,
+ "Failed to assign pci device!\n");
+ kfree(pcidev);
+ break;
+ case ACRN_IOCTL_DEASSIGN_PCIDEV:
+ pcidev = memdup_user((void __user *)ioctl_param,
+ sizeof(struct acrn_pcidev));
+ if (IS_ERR(pcidev))
+ return PTR_ERR(pcidev);
+
+ ret = hcall_deassign_pcidev(vm->vmid, virt_to_phys(pcidev));
+ if (ret < 0)
+ dev_err(acrn_dev.this_device,
+ "Failed to deassign pci device!\n");
+ kfree(pcidev);
+ break;
+ case ACRN_IOCTL_SET_PTDEV_INTR:
+ irq_info = memdup_user((void __user *)ioctl_param,
+ sizeof(struct acrn_ptdev_irq));
+ if (IS_ERR(irq_info))
+ return PTR_ERR(irq_info);
+
+ ret = hcall_set_ptdev_intr(vm->vmid, virt_to_phys(irq_info));
+ if (ret < 0)
+ dev_err(acrn_dev.this_device,
+ "Failed to configure intr for ptdev!\n");
+ kfree(irq_info);
+ break;
+ case ACRN_IOCTL_RESET_PTDEV_INTR:
+ irq_info = memdup_user((void __user *)ioctl_param,
+ sizeof(struct acrn_ptdev_irq));
+ if (IS_ERR(irq_info))
+ return PTR_ERR(irq_info);
+
+ ret = hcall_reset_ptdev_intr(vm->vmid, virt_to_phys(irq_info));
+ if (ret < 0)
+ dev_err(acrn_dev.this_device,
+ "Failed to reset intr for ptdev!\n");
+ kfree(irq_info);
+ break;
case ACRN_IOCTL_CREATE_IOREQ_CLIENT:
if (vm->default_client)
return -EEXIST;
diff --git a/drivers/virt/acrn/hypercall.h b/drivers/virt/acrn/hypercall.h
index 5eba29e3ed38..f448301832cf 100644
--- a/drivers/virt/acrn/hypercall.h
+++ b/drivers/virt/acrn/hypercall.h
@@ -28,6 +28,12 @@
#define HC_ID_MEM_BASE 0x40UL
#define HC_VM_SET_MEMORY_REGIONS _HC_ID(HC_ID, HC_ID_MEM_BASE + 0x02)

+#define HC_ID_PCI_BASE 0x50UL
+#define HC_SET_PTDEV_INTR _HC_ID(HC_ID, HC_ID_PCI_BASE + 0x03)
+#define HC_RESET_PTDEV_INTR _HC_ID(HC_ID, HC_ID_PCI_BASE + 0x04)
+#define HC_ASSIGN_PCIDEV _HC_ID(HC_ID, HC_ID_PCI_BASE + 0x05)
+#define HC_DEASSIGN_PCIDEV _HC_ID(HC_ID, HC_ID_PCI_BASE + 0x06)
+
/**
* hcall_create_vm() - Create a User VM
* @vminfo: Service VM GPA of info of User VM creation
@@ -130,4 +136,52 @@ static inline long hcall_set_memory_regions(u64 regions_pa)
return acrn_hypercall1(HC_VM_SET_MEMORY_REGIONS, regions_pa);
}

+/**
+ * hcall_assign_pcidev() - Assign a PCI device to a User VM
+ * @vmid: User VM ID
+ * @addr: Service VM GPA of the &struct acrn_pcidev
+ *
+ * Return: 0 on success, <0 on failure
+ */
+static inline long hcall_assign_pcidev(u64 vmid, u64 addr)
+{
+ return acrn_hypercall2(HC_ASSIGN_PCIDEV, vmid, addr);
+}
+
+/**
+ * hcall_deassign_pcidev() - De-assign a PCI device from a User VM
+ * @vmid: User VM ID
+ * @addr: Service VM GPA of the &struct acrn_pcidev
+ *
+ * Return: 0 on success, <0 on failure
+ */
+static inline long hcall_deassign_pcidev(u64 vmid, u64 addr)
+{
+ return acrn_hypercall2(HC_DEASSIGN_PCIDEV, vmid, addr);
+}
+
+/**
+ * hcall_set_ptdev_intr() - Configure an interrupt for an assigned PCI device.
+ * @vmid: User VM ID
+ * @irq: Service VM GPA of the &struct acrn_ptdev_irq
+ *
+ * Return: 0 on success, <0 on failure
+ */
+static inline long hcall_set_ptdev_intr(u64 vmid, u64 irq)
+{
+ return acrn_hypercall2(HC_SET_PTDEV_INTR, vmid, irq);
+}
+
+/**
+ * hcall_reset_ptdev_intr() - Reset an interrupt for an assigned PCI device.
+ * @vmid: User VM ID
+ * @irq: Service VM GPA of the &struct acrn_ptdev_irq
+ *
+ * Return: 0 on success, <0 on failure
+ */
+static inline long hcall_reset_ptdev_intr(u64 vmid, u64 irq)
+{
+ return acrn_hypercall2(HC_RESET_PTDEV_INTR, vmid, irq);
+}
+
#endif /* __ACRN_HSM_HYPERCALL_H */
diff --git a/include/uapi/linux/acrn.h b/include/uapi/linux/acrn.h
index 31cf0fd73bcc..893389babbcb 100644
--- a/include/uapi/linux/acrn.h
+++ b/include/uapi/linux/acrn.h
@@ -289,6 +289,60 @@ struct acrn_vm_memmap {
__u32 attr;
} __attribute__((aligned(8)));

+/* Type of interrupt of a passthrough device */
+#define ACRN_PTDEV_IRQ_INTX 0
+#define ACRN_PTDEV_IRQ_MSI 1
+#define ACRN_PTDEV_IRQ_MSIX 2
+/**
+ * struct acrn_ptdev_irq - Interrupt data of a passthrough device.
+ * @type: Type (ACRN_PTDEV_IRQ_*)
+ * @virt_bdf: Virtual Bus/Device/Function
+ * @phys_bdf: Physical Bus/Device/Function
+ * @intx: Info of interrupt
+ * @intx.virt_pin: Virtual IOAPIC pin
+ * @intx.phys_pin: Physical IOAPIC pin
+ * @intx.is_pic_pin: Is PIC pin or not
+ *
+ * This structure will be passed to hypervisor directly.
+ */
+struct acrn_ptdev_irq {
+ __u32 type;
+ __u16 virt_bdf;
+ __u16 phys_bdf;
+
+ struct {
+ __u32 virt_pin;
+ __u32 phys_pin;
+ __u32 is_pic_pin;
+ } intx;
+} __attribute__((aligned(8)));
+
+/* Type of PCI device assignment */
+#define ACRN_PTDEV_QUIRK_ASSIGN (1U << 0)
+
+#define ACRN_PCI_NUM_BARS 6
+/**
+ * struct acrn_pcidev - Info for assigning or de-assigning a PCI device
+ * @type: Type of the assignment
+ * @virt_bdf: Virtual Bus/Device/Function
+ * @phys_bdf: Physical Bus/Device/Function
+ * @intr_line: PCI interrupt line
+ * @intr_pin: PCI interrupt pin
+ * @bar: PCI BARs.
+ * @reserved: Reserved.
+ *
+ * This structure will be passed to hypervisor directly.
+ */
+struct acrn_pcidev {
+ __u32 type;
+ __u16 virt_bdf;
+ __u16 phys_bdf;
+ __u8 intr_line;
+ __u8 intr_pin;
+ __u32 bar[ACRN_PCI_NUM_BARS];
+ __u32 reserved[6];
+} __attribute__((aligned(8)));
+
/* The ioctl type, documented in ioctl-number.rst */
#define ACRN_IOCTL_TYPE 0xA2

@@ -324,4 +378,13 @@ struct acrn_vm_memmap {
#define ACRN_IOCTL_UNSET_MEMSEG \
_IOW(ACRN_IOCTL_TYPE, 0x42, struct acrn_vm_memmap)

+#define ACRN_IOCTL_SET_PTDEV_INTR \
+ _IOW(ACRN_IOCTL_TYPE, 0x53, struct acrn_ptdev_irq)
+#define ACRN_IOCTL_RESET_PTDEV_INTR \
+ _IOW(ACRN_IOCTL_TYPE, 0x54, struct acrn_ptdev_irq)
+#define ACRN_IOCTL_ASSIGN_PCIDEV \
+ _IOW(ACRN_IOCTL_TYPE, 0x55, struct acrn_pcidev)
+#define ACRN_IOCTL_DEASSIGN_PCIDEV \
+ _IOW(ACRN_IOCTL_TYPE, 0x56, struct acrn_pcidev)
+
#endif /* _UAPI_ACRN_H */
--
2.28.0