virt: acrn: Introduce interfaces for MMIO device passthrough

MMIO device passthrough enables an OS in a virtual machine to directly
access a MMIO 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_MMIODEV
    Pass data struct acrn_mmiodev from userspace to the hypervisor, and
    inform the hypervisor to assign a MMIO device to a User VM.

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

These new APIs will be used by user space code vm_assign_mmiodev and
vm_deassign_mmiodev in
https://github.com/projectacrn/acrn-hypervisor/blob/master/devicemodel/core/vmmapi.c

Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Signed-off-by: Fei Li <fei1.li@intel.com>
Link: https://lore.kernel.org/r/20210923084128.18902-2-fei1.li@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Shuo Liu 2021-09-23 16:41:27 +08:00 committed by Greg Kroah-Hartman
parent c31bbc140b
commit 29a9f27574
3 changed files with 79 additions and 0 deletions

View File

@ -114,6 +114,7 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd,
struct acrn_ptdev_irq *irq_info;
struct acrn_ioeventfd ioeventfd;
struct acrn_vm_memmap memmap;
struct acrn_mmiodev *mmiodev;
struct acrn_msi_entry *msi;
struct acrn_pcidev *pcidev;
struct acrn_irqfd irqfd;
@ -217,6 +218,30 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd,
ret = acrn_vm_memseg_unmap(vm, &memmap);
break;
case ACRN_IOCTL_ASSIGN_MMIODEV:
mmiodev = memdup_user((void __user *)ioctl_param,
sizeof(struct acrn_mmiodev));
if (IS_ERR(mmiodev))
return PTR_ERR(mmiodev);
ret = hcall_assign_mmiodev(vm->vmid, virt_to_phys(mmiodev));
if (ret < 0)
dev_dbg(acrn_dev.this_device,
"Failed to assign MMIO device!\n");
kfree(mmiodev);
break;
case ACRN_IOCTL_DEASSIGN_MMIODEV:
mmiodev = memdup_user((void __user *)ioctl_param,
sizeof(struct acrn_mmiodev));
if (IS_ERR(mmiodev))
return PTR_ERR(mmiodev);
ret = hcall_deassign_mmiodev(vm->vmid, virt_to_phys(mmiodev));
if (ret < 0)
dev_dbg(acrn_dev.this_device,
"Failed to deassign MMIO device!\n");
kfree(mmiodev);
break;
case ACRN_IOCTL_ASSIGN_PCIDEV:
pcidev = memdup_user((void __user *)ioctl_param,
sizeof(struct acrn_pcidev));

View File

@ -41,6 +41,8 @@
#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)
#define HC_ASSIGN_MMIODEV _HC_ID(HC_ID, HC_ID_PCI_BASE + 0x07)
#define HC_DEASSIGN_MMIODEV _HC_ID(HC_ID, HC_ID_PCI_BASE + 0x08)
#define HC_ID_PM_BASE 0x80UL
#define HC_PM_GET_CPU_STATE _HC_ID(HC_ID, HC_ID_PM_BASE + 0x00)
@ -194,6 +196,30 @@ static inline long hcall_set_memory_regions(u64 regions_pa)
return acrn_hypercall1(HC_VM_SET_MEMORY_REGIONS, regions_pa);
}
/**
* hcall_assign_mmiodev() - Assign a MMIO device to a User VM
* @vmid: User VM ID
* @addr: Service VM GPA of the &struct acrn_mmiodev
*
* Return: 0 on success, <0 on failure
*/
static inline long hcall_assign_mmiodev(u64 vmid, u64 addr)
{
return acrn_hypercall2(HC_ASSIGN_MMIODEV, vmid, addr);
}
/**
* hcall_deassign_mmiodev() - De-assign a PCI device from a User VM
* @vmid: User VM ID
* @addr: Service VM GPA of the &struct acrn_mmiodev
*
* Return: 0 on success, <0 on failure
*/
static inline long hcall_deassign_mmiodev(u64 vmid, u64 addr)
{
return acrn_hypercall2(HC_DEASSIGN_MMIODEV, vmid, addr);
}
/**
* hcall_assign_pcidev() - Assign a PCI device to a User VM
* @vmid: User VM ID

View File

@ -396,6 +396,7 @@ struct acrn_ptdev_irq {
/* Type of PCI device assignment */
#define ACRN_PTDEV_QUIRK_ASSIGN (1U << 0)
#define ACRN_MMIODEV_RES_NUM 3
#define ACRN_PCI_NUM_BARS 6
/**
* struct acrn_pcidev - Info for assigning or de-assigning a PCI device
@ -417,6 +418,29 @@ struct acrn_pcidev {
__u32 bar[ACRN_PCI_NUM_BARS];
};
/**
* struct acrn_mmiodev - Info for assigning or de-assigning a MMIO device
* @name: Name of the MMIO device.
* @res[].user_vm_pa: Physical address of User VM of the MMIO region
* for the MMIO device.
* @res[].service_vm_pa: Physical address of Service VM of the MMIO
* region for the MMIO device.
* @res[].size: Size of the MMIO region for the MMIO device.
* @res[].mem_type: Memory type of the MMIO region for the MMIO
* device.
*
* This structure will be passed to hypervisor directly.
*/
struct acrn_mmiodev {
__u8 name[8];
struct {
__u64 user_vm_pa;
__u64 service_vm_pa;
__u64 size;
__u64 mem_type;
} res[ACRN_MMIODEV_RES_NUM];
};
/**
* struct acrn_msi_entry - Info for injecting a MSI interrupt to a VM
* @msi_addr: MSI addr[19:12] with dest vCPU ID
@ -568,6 +592,10 @@ struct acrn_irqfd {
_IOW(ACRN_IOCTL_TYPE, 0x55, struct acrn_pcidev)
#define ACRN_IOCTL_DEASSIGN_PCIDEV \
_IOW(ACRN_IOCTL_TYPE, 0x56, struct acrn_pcidev)
#define ACRN_IOCTL_ASSIGN_MMIODEV \
_IOW(ACRN_IOCTL_TYPE, 0x57, struct acrn_mmiodev)
#define ACRN_IOCTL_DEASSIGN_MMIODEV \
_IOW(ACRN_IOCTL_TYPE, 0x58, struct acrn_mmiodev)
#define ACRN_IOCTL_PM_GET_CPU_STATE \
_IOWR(ACRN_IOCTL_TYPE, 0x60, __u64)