Commit ad6260da authored by Paolo Bonzini's avatar Paolo Bonzini Committed by Radim Krčmář
Browse files

KVM: x86: drop legacy device assignment 



Legacy device assignment has been deprecated since 4.2 (released
1.5 years ago).  VFIO is better and everyone should have switched to it.
If they haven't, this should convince them. :)

Reviewed-by: default avatarAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 2c82878b

Documentation/virtual/kvm/api.txt

+0 −204
Original line number Diff line number Diff line
@@ -1326,130 +1326,6 @@ The flags bitmap is defined as: 
   /* the host supports the ePAPR idle hcall

   #define KVM_PPC_PVINFO_FLAGS_EV_IDLE   (1<<0)



4.48 KVM_ASSIGN_PCI_DEVICE (deprecated)



Capability: none

Architectures: x86

Type: vm ioctl

Parameters: struct kvm_assigned_pci_dev (in)

Returns: 0 on success, -1 on error



Assigns a host PCI device to the VM.



struct kvm_assigned_pci_dev {

	__u32 assigned_dev_id;

	__u32 busnr;

	__u32 devfn;

	__u32 flags;

	__u32 segnr;

	union {

		__u32 reserved[11];

	};

};



The PCI device is specified by the triple segnr, busnr, and devfn.

Identification in succeeding service requests is done via assigned_dev_id. The

following flags are specified:



/* Depends on KVM_CAP_IOMMU */

#define KVM_DEV_ASSIGN_ENABLE_IOMMU	(1 << 0)

/* The following two depend on KVM_CAP_PCI_2_3 */

#define KVM_DEV_ASSIGN_PCI_2_3		(1 << 1)

#define KVM_DEV_ASSIGN_MASK_INTX	(1 << 2)



If KVM_DEV_ASSIGN_PCI_2_3 is set, the kernel will manage legacy INTx interrupts

via the PCI-2.3-compliant device-level mask, thus enable IRQ sharing with other

assigned devices or host devices. KVM_DEV_ASSIGN_MASK_INTX specifies the

guest's view on the INTx mask, see KVM_ASSIGN_SET_INTX_MASK for details.



The KVM_DEV_ASSIGN_ENABLE_IOMMU flag is a mandatory option to ensure

isolation of the device.  Usages not specifying this flag are deprecated.



Only PCI header type 0 devices with PCI BAR resources are supported by

device assignment.  The user requesting this ioctl must have read/write

access to the PCI sysfs resource files associated with the device.



Errors:

  ENOTTY: kernel does not support this ioctl



  Other error conditions may be defined by individual device types or

  have their standard meanings.





4.49 KVM_DEASSIGN_PCI_DEVICE (deprecated)



Capability: none

Architectures: x86

Type: vm ioctl

Parameters: struct kvm_assigned_pci_dev (in)

Returns: 0 on success, -1 on error



Ends PCI device assignment, releasing all associated resources.



See KVM_ASSIGN_PCI_DEVICE for the data structure. Only assigned_dev_id is

used in kvm_assigned_pci_dev to identify the device.



Errors:

  ENOTTY: kernel does not support this ioctl



  Other error conditions may be defined by individual device types or

  have their standard meanings.



4.50 KVM_ASSIGN_DEV_IRQ (deprecated)



Capability: KVM_CAP_ASSIGN_DEV_IRQ

Architectures: x86

Type: vm ioctl

Parameters: struct kvm_assigned_irq (in)

Returns: 0 on success, -1 on error



Assigns an IRQ to a passed-through device.



struct kvm_assigned_irq {

	__u32 assigned_dev_id;

	__u32 host_irq; /* ignored (legacy field) */

	__u32 guest_irq;

	__u32 flags;

	union {

		__u32 reserved[12];

	};

};



The following flags are defined:



#define KVM_DEV_IRQ_HOST_INTX    (1 << 0)

#define KVM_DEV_IRQ_HOST_MSI     (1 << 1)

#define KVM_DEV_IRQ_HOST_MSIX    (1 << 2)



#define KVM_DEV_IRQ_GUEST_INTX   (1 << 8)

#define KVM_DEV_IRQ_GUEST_MSI    (1 << 9)

#define KVM_DEV_IRQ_GUEST_MSIX   (1 << 10)



It is not valid to specify multiple types per host or guest IRQ. However, the

IRQ type of host and guest can differ or can even be null.



Errors:

  ENOTTY: kernel does not support this ioctl



  Other error conditions may be defined by individual device types or

  have their standard meanings.





4.51 KVM_DEASSIGN_DEV_IRQ (deprecated)



Capability: KVM_CAP_ASSIGN_DEV_IRQ

Architectures: x86

Type: vm ioctl

Parameters: struct kvm_assigned_irq (in)

Returns: 0 on success, -1 on error



Ends an IRQ assignment to a passed-through device.



See KVM_ASSIGN_DEV_IRQ for the data structure. The target device is specified

by assigned_dev_id, flags must correspond to the IRQ type specified on

KVM_ASSIGN_DEV_IRQ. Partial deassignment of host or guest IRQ is allowed.





4.52 KVM_SET_GSI_ROUTING



Capability: KVM_CAP_IRQ_ROUTING
@@ -1536,52 +1412,6 @@ struct kvm_irq_routing_hv_sint { 
	__u32 sint;

};



4.53 KVM_ASSIGN_SET_MSIX_NR (deprecated)



Capability: none

Architectures: x86

Type: vm ioctl

Parameters: struct kvm_assigned_msix_nr (in)

Returns: 0 on success, -1 on error



Set the number of MSI-X interrupts for an assigned device. The number is

reset again by terminating the MSI-X assignment of the device via

KVM_DEASSIGN_DEV_IRQ. Calling this service more than once at any earlier

point will fail.



struct kvm_assigned_msix_nr {

	__u32 assigned_dev_id;

	__u16 entry_nr;

	__u16 padding;

};



#define KVM_MAX_MSIX_PER_DEV		256





4.54 KVM_ASSIGN_SET_MSIX_ENTRY (deprecated)



Capability: none

Architectures: x86

Type: vm ioctl

Parameters: struct kvm_assigned_msix_entry (in)

Returns: 0 on success, -1 on error



Specifies the routing of an MSI-X assigned device interrupt to a GSI. Setting

the GSI vector to zero means disabling the interrupt.



struct kvm_assigned_msix_entry {

	__u32 assigned_dev_id;

	__u32 gsi;

	__u16 entry; /* The index of entry in the MSI-X table */

	__u16 padding[3];

};



Errors:

  ENOTTY: kernel does not support this ioctl



  Other error conditions may be defined by individual device types or

  have their standard meanings.





4.55 KVM_SET_TSC_KHZ
@@ -1733,40 +1563,6 @@ should skip processing the bitmap and just invalidate everything. It must 
be set to the number of set bits in the bitmap.





4.61 KVM_ASSIGN_SET_INTX_MASK (deprecated)



Capability: KVM_CAP_PCI_2_3

Architectures: x86

Type: vm ioctl

Parameters: struct kvm_assigned_pci_dev (in)

Returns: 0 on success, -1 on error



Allows userspace to mask PCI INTx interrupts from the assigned device.  The

kernel will not deliver INTx interrupts to the guest between setting and

clearing of KVM_ASSIGN_SET_INTX_MASK via this interface.  This enables use of

and emulation of PCI 2.3 INTx disable command register behavior.



This may be used for both PCI 2.3 devices supporting INTx disable natively and

older devices lacking this support. Userspace is responsible for emulating the

read value of the INTx disable bit in the guest visible PCI command register.

When modifying the INTx disable state, userspace should precede updating the

physical device command register by calling this ioctl to inform the kernel of

the new intended INTx mask state.



Note that the kernel uses the device INTx disable bit to internally manage the

device interrupt state for PCI 2.3 devices.  Reads of this register may

therefore not match the expected value.  Writes should always use the guest

intended INTx disable value rather than attempting to read-copy-update the

current physical device state.  Races between user and kernel updates to the

INTx disable bit are handled lazily in the kernel.  It's possible the device

may generate unintended interrupts, but they will not be injected into the

guest.



See KVM_ASSIGN_DEV_IRQ for the data structure.  The target device is specified

by assigned_dev_id.  In the flags field, only KVM_DEV_ASSIGN_MASK_INTX is

evaluated.





4.62 KVM_CREATE_SPAPR_TCE



Capability: KVM_CAP_SPAPR_TCE

arch/x86/kvm/Kconfig

+0 −12
Original line number Diff line number Diff line
@@ -86,18 +86,6 @@ config KVM_MMU_AUDIT 
	 This option adds a R/W kVM module parameter 'mmu_audit', which allows

	 auditing of KVM MMU events at runtime.



config KVM_DEVICE_ASSIGNMENT

	bool "KVM legacy PCI device assignment support (DEPRECATED)"

	depends on KVM && PCI && IOMMU_API

	default n

	---help---

	  Provide support for legacy PCI device assignment through KVM.  The

	  kernel now also supports a full featured userspace device driver

	  framework through VFIO, which supersedes this support and provides

	  better security.



	  If unsure, say N.



# OK, it's a little counter-intuitive to do this, but it puts it neatly under

# the virtualization menu.

source drivers/vhost/Kconfig

arch/x86/kvm/Makefile

+0 −2
Original line number Diff line number Diff line
@@ -15,8 +15,6 @@ kvm-y += x86.o mmu.o emulate.o i8259.o irq.o lapic.o \ 
			   i8254.o ioapic.o irq_comm.o cpuid.o pmu.o mtrr.o \

			   hyperv.o page_track.o debugfs.o



kvm-$(CONFIG_KVM_DEVICE_ASSIGNMENT)	+= assigned-dev.o iommu.o



kvm-intel-y		+= vmx.o pmu_intel.o

kvm-amd-y		+= svm.o pmu_amd.o