Commit ce011e13 authored by Shuo Liu's avatar Shuo Liu Committed by Greg Kroah-Hartman
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virt: acrn: Introduce interfaces for PCI device passthrough 



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.

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>
Reviewed-by: default avatarZhi Wang <zhi.a.wang@intel.com>
Reviewed-by: default avatarReinette Chatre <reinette.chatre@intel.com>
Signed-off-by: default avatarShuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-12-shuo.a.liu@intel.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 3c4c3316

drivers/virt/acrn/hsm.c

+50 −0
Original line number Diff line number Diff line
@@ -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 i, ret = 0;



	if (vm->vmid == ACRN_INVALID_VMID && cmd != ACRN_IOCTL_CREATE_VM) {
@@ -148,6 +150,54 @@ 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_dbg(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_dbg(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_dbg(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_dbg(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;

drivers/virt/acrn/hypercall.h

+54 −0
Original line number Diff line number Diff line
@@ -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 */

include/uapi/linux/acrn.h

+61 −0
Original line number Diff line number Diff line
@@ -365,6 +365,58 @@ struct acrn_vm_memmap { 
	__u64	len;

};



/* 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;

};



/* 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.

 *

 * 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];

};



/* The ioctl type, documented in ioctl-number.rst */

#define ACRN_IOCTL_TYPE			0xA2
@@ -400,4 +452,13 @@ 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 */