Re: [PATCH] KVM: x86: drop legacy device assignment

[Paolo Bonzini <pbonzini@redhat.com>]

On 27/03/2017 16:42, Alex Williamson wrote:
> Yes, it's been deprecated since v4.2.  I'd suggest also updating
> Documentation/virtual/kvm/api.txt.

Good point:

diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index fd106899afd1..9c886307268c 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -1321,130 +1321,6 @@ 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
@@ -1531,52 +1407,6 @@ 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
 
@@ -1728,40 +1558,6 @@ 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


> 
> Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
>