KVM: PPC: Book3S: Add API for in-kernel XICS emulation (5975a2e0) · Commits · 戴 / test

Documentation/virtual/kvm/api.txt

+8 −0

Original line number	Diff line number	Diff line
		@@ -2772,3 +2772,11 @@ Parameters: args[0] is the MPIC device fd
		args[1] is the MPIC CPU number for this vcpu

		This capability connects the vcpu to an in-kernel MPIC device.

		6.7 KVM_CAP_IRQ_XICS

		Architectures: ppc
		Parameters: args[0] is the XICS device fd
		args[1] is the XICS CPU number (server ID) for this vcpu

		This capability connects the vcpu to an in-kernel XICS device.

Documentation/virtual/kvm/devices/xics.txt

0 → 100644

+66 −0

Original line number	Diff line number	Diff line
		XICS interrupt controller

		Device type supported: KVM_DEV_TYPE_XICS

		Groups:
		KVM_DEV_XICS_SOURCES
		Attributes: One per interrupt source, indexed by the source number.

		This device emulates the XICS (eXternal Interrupt Controller
		Specification) defined in PAPR. The XICS has a set of interrupt
		sources, each identified by a 20-bit source number, and a set of
		Interrupt Control Presentation (ICP) entities, also called "servers",
		each associated with a virtual CPU.

		The ICP entities are created by enabling the KVM_CAP_IRQ_ARCH
		capability for each vcpu, specifying KVM_CAP_IRQ_XICS in args[0] and
		the interrupt server number (i.e. the vcpu number from the XICS's
		point of view) in args[1] of the kvm_enable_cap struct. Each ICP has
		64 bits of state which can be read and written using the
		KVM_GET_ONE_REG and KVM_SET_ONE_REG ioctls on the vcpu. The 64 bit
		state word has the following bitfields, starting at the
		least-significant end of the word:

		* Unused, 16 bits

		* Pending interrupt priority, 8 bits
		Zero is the highest priority, 255 means no interrupt is pending.

		* Pending IPI (inter-processor interrupt) priority, 8 bits
		Zero is the highest priority, 255 means no IPI is pending.

		* Pending interrupt source number, 24 bits
		Zero means no interrupt pending, 2 means an IPI is pending

		* Current processor priority, 8 bits
		Zero is the highest priority, meaning no interrupts can be
		delivered, and 255 is the lowest priority.

		Each source has 64 bits of state that can be read and written using
		the KVM_GET_DEVICE_ATTR and KVM_SET_DEVICE_ATTR ioctls, specifying the
		KVM_DEV_XICS_SOURCES attribute group, with the attribute number being
		the interrupt source number. The 64 bit state word has the following
		bitfields, starting from the least-significant end of the word:

		* Destination (server number), 32 bits
		This specifies where the interrupt should be sent, and is the
		interrupt server number specified for the destination vcpu.

		* Priority, 8 bits
		This is the priority specified for this interrupt source, where 0 is
		the highest priority and 255 is the lowest. An interrupt with a
		priority of 255 will never be delivered.

		* Level sensitive flag, 1 bit
		This bit is 1 for a level-sensitive interrupt source, or 0 for
		edge-sensitive (or MSI).

		* Masked flag, 1 bit
		This bit is set to 1 if the interrupt is masked (cannot be delivered
		regardless of its priority), for example by the ibm,int-off RTAS
		call, or 0 if it is not masked.

		* Pending flag, 1 bit
		This bit is 1 if the source has a pending interrupt, otherwise 0.

		Only one XICS instance may be created per VM.

arch/powerpc/include/asm/kvm_ppc.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -315,6 +315,8 @@ extern int kvm_vm_ioctl_xics_irq(struct kvm kvm, struct kvm_irq_level args);
		extern int kvmppc_xics_hcall(struct kvm_vcpu *vcpu, u32 cmd);
		extern u64 kvmppc_xics_get_icp(struct kvm_vcpu *vcpu);
		extern int kvmppc_xics_set_icp(struct kvm_vcpu *vcpu, u64 icpval);
		extern int kvmppc_xics_connect_vcpu(struct kvm_device *dev,
		struct kvm_vcpu *vcpu, u32 cpu);
		#else
		static inline int kvmppc_xics_enabled(struct kvm_vcpu *vcpu)
		{ return 0; }

arch/powerpc/include/uapi/asm/kvm.h

+12 −0

Original line number	Diff line number	Diff line
		@@ -499,4 +499,16 @@ struct kvm_get_htab_header {
		#define KVM_REG_PPC_TLB3PS (KVM_REG_PPC \| KVM_REG_SIZE_U32 \| 0x9a)
		#define KVM_REG_PPC_EPTCFG (KVM_REG_PPC \| KVM_REG_SIZE_U32 \| 0x9b)

		/* PPC64 eXternal Interrupt Controller Specification */
		#define KVM_DEV_XICS_GRP_SOURCES 1 /* 64-bit source attributes */

		/* Layout of 64-bit source attribute values */
		#define KVM_XICS_DESTINATION_SHIFT 0
		#define KVM_XICS_DESTINATION_MASK 0xffffffffULL
		#define KVM_XICS_PRIORITY_SHIFT 32
		#define KVM_XICS_PRIORITY_MASK 0xff
		#define KVM_XICS_LEVEL_SENSITIVE (1ULL << 40)
		#define KVM_XICS_MASKED (1ULL << 41)
		#define KVM_XICS_PENDING (1ULL << 42)

		#endif /* __LINUX_KVM_POWERPC_H */

arch/powerpc/kvm/book3s_xics.c

+165 −25

Original line number	Diff line number	Diff line
		@@ -11,6 +11,7 @@
		#include <linux/kvm_host.h>
		#include <linux/err.h>
		#include <linux/gfp.h>
		#include <linux/anon_inodes.h>

		#include <asm/uaccess.h>
		#include <asm/kvm_book3s.h>
		@@ -55,8 +56,6 @@
		*
		* - Make ICS lockless as well, or at least a per-interrupt lock or hashed
		* locks array to improve scalability
		*
		* - ioctl's to save/restore the entire state for snapshot & migration
		*/

		/* -- ICS routines -- */
		@@ -64,7 +63,8 @@
		static void icp_deliver_irq(struct kvmppc_xics xics, struct kvmppc_icp icp,
		u32 new_irq);

		static int ics_deliver_irq(struct kvmppc_xics *xics, u32 irq, u32 level)
		static int ics_deliver_irq(struct kvmppc_xics *xics, u32 irq, u32 level,
		bool report_status)
		{
		struct ics_irq_state *state;
		struct kvmppc_ics *ics;
		@@ -81,6 +81,9 @@ static int ics_deliver_irq(struct kvmppc_xics *xics, u32 irq, u32 level)
		if (!state->exists)
		return -EINVAL;

		if (report_status)
		return state->asserted;

		/*
		* We set state->asserted locklessly. This should be fine as
		* we are the only setter, thus concurrent access is undefined
		@@ -96,7 +99,7 @@ static int ics_deliver_irq(struct kvmppc_xics *xics, u32 irq, u32 level)
		/* Attempt delivery */
		icp_deliver_irq(xics, NULL, irq);

		return 0;
		return state->asserted;
		}

		static void ics_check_resend(struct kvmppc_xics xics, struct kvmppc_ics ics,
		@@ -891,7 +894,7 @@ static void xics_debugfs_init(struct kvmppc_xics *xics)
		kfree(name);
		}

		struct kvmppc_ics kvmppc_xics_create_ics(struct kvm kvm,
		static struct kvmppc_ics kvmppc_xics_create_ics(struct kvm kvm,
		struct kvmppc_xics *xics, int irq)
		{
		struct kvmppc_ics *ics;
		@@ -1044,34 +1047,138 @@ int kvmppc_xics_set_icp(struct kvm_vcpu *vcpu, u64 icpval)
		return 0;
		}

		/* -- ioctls -- */
		static int xics_get_source(struct kvmppc_xics *xics, long irq, u64 addr)
		{
		int ret;
		struct kvmppc_ics *ics;
		struct ics_irq_state *irqp;
		u64 __user ubufp = (u64 __user ) addr;
		u16 idx;
		u64 val, prio;

		ics = kvmppc_xics_find_ics(xics, irq, &idx);
		if (!ics)
		return -ENOENT;

		irqp = &ics->irq_state[idx];
		mutex_lock(&ics->lock);
		ret = -ENOENT;
		if (irqp->exists) {
		val = irqp->server;
		prio = irqp->priority;
		if (prio == MASKED) {
		val \|= KVM_XICS_MASKED;
		prio = irqp->saved_priority;
		}
		val \|= prio << KVM_XICS_PRIORITY_SHIFT;
		if (irqp->asserted)
		val \|= KVM_XICS_LEVEL_SENSITIVE \| KVM_XICS_PENDING;
		else if (irqp->masked_pending \|\| irqp->resend)
		val \|= KVM_XICS_PENDING;
		ret = 0;
		}
		mutex_unlock(&ics->lock);

		if (!ret && put_user(val, ubufp))
		ret = -EFAULT;

		int kvm_vm_ioctl_xics_irq(struct kvm kvm, struct kvm_irq_level args)
		return ret;
		}

		static int xics_set_source(struct kvmppc_xics *xics, long irq, u64 addr)
		{
		struct kvmppc_xics *xics;
		int r;
		struct kvmppc_ics *ics;
		struct ics_irq_state *irqp;
		u64 __user ubufp = (u64 __user ) addr;
		u16 idx;
		u64 val;
		u8 prio;
		u32 server;

		if (irq < KVMPPC_XICS_FIRST_IRQ \|\| irq >= KVMPPC_XICS_NR_IRQS)
		return -ENOENT;

		/* locking against multiple callers? */
		ics = kvmppc_xics_find_ics(xics, irq, &idx);
		if (!ics) {
		ics = kvmppc_xics_create_ics(xics->kvm, xics, irq);
		if (!ics)
		return -ENOMEM;
		}
		irqp = &ics->irq_state[idx];
		if (get_user(val, ubufp))
		return -EFAULT;

		server = val & KVM_XICS_DESTINATION_MASK;
		prio = val >> KVM_XICS_PRIORITY_SHIFT;
		if (prio != MASKED &&
		kvmppc_xics_find_server(xics->kvm, server) == NULL)
		return -EINVAL;

		xics = kvm->arch.xics;
		if (!xics)
		return -ENODEV;
		mutex_lock(&ics->lock);
		irqp->server = server;
		irqp->saved_priority = prio;
		if (val & KVM_XICS_MASKED)
		prio = MASKED;
		irqp->priority = prio;
		irqp->resend = 0;
		irqp->masked_pending = 0;
		irqp->asserted = 0;
		if ((val & KVM_XICS_PENDING) && (val & KVM_XICS_LEVEL_SENSITIVE))
		irqp->asserted = 1;
		irqp->exists = 1;
		mutex_unlock(&ics->lock);

		switch (args->level) {
		case KVM_INTERRUPT_SET:
		case KVM_INTERRUPT_SET_LEVEL:
		case KVM_INTERRUPT_UNSET:
		r = ics_deliver_irq(xics, args->irq, args->level);
		break;
		default:
		r = -EINVAL;
		if (val & KVM_XICS_PENDING)
		icp_deliver_irq(xics, NULL, irqp->number);

		return 0;
		}

		return r;
		int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level,
		bool line_status)
		{
		struct kvmppc_xics *xics = kvm->arch.xics;

		return ics_deliver_irq(xics, irq, level, line_status);
		}

		static int xics_set_attr(struct kvm_device dev, struct kvm_device_attr attr)
		{
		struct kvmppc_xics *xics = dev->private;

		switch (attr->group) {
		case KVM_DEV_XICS_GRP_SOURCES:
		return xics_set_source(xics, attr->attr, attr->addr);
		}
		return -ENXIO;
		}

		static int xics_get_attr(struct kvm_device dev, struct kvm_device_attr attr)
		{
		struct kvmppc_xics *xics = dev->private;

		switch (attr->group) {
		case KVM_DEV_XICS_GRP_SOURCES:
		return xics_get_source(xics, attr->attr, attr->addr);
		}
		return -ENXIO;
		}

		void kvmppc_xics_free(struct kvmppc_xics *xics)
		static int xics_has_attr(struct kvm_device dev, struct kvm_device_attr attr)
		{
		switch (attr->group) {
		case KVM_DEV_XICS_GRP_SOURCES:
		if (attr->attr >= KVMPPC_XICS_FIRST_IRQ &&
		attr->attr < KVMPPC_XICS_NR_IRQS)
		return 0;
		break;
		}
		return -ENXIO;
		}

		static void kvmppc_xics_free(struct kvm_device *dev)
		{
		struct kvmppc_xics *xics = dev->private;
		int i;
		struct kvm *kvm = xics->kvm;

		@@ -1083,17 +1190,21 @@ void kvmppc_xics_free(struct kvmppc_xics *xics)
		for (i = 0; i <= xics->max_icsid; i++)
		kfree(xics->ics[i]);
		kfree(xics);
		kfree(dev);
		}

		int kvm_xics_create(struct kvm *kvm, u32 type)
		static int kvmppc_xics_create(struct kvm_device *dev, u32 type)
		{
		struct kvmppc_xics *xics;
		struct kvm *kvm = dev->kvm;
		int ret = 0;

		xics = kzalloc(sizeof(*xics), GFP_KERNEL);
		if (!xics)
		return -ENOMEM;

		dev->private = xics;
		xics->dev = dev;
		xics->kvm = kvm;

		/* Already there ? */
		@@ -1120,6 +1231,35 @@ int kvm_xics_create(struct kvm *kvm, u32 type)
		return 0;
		}

		struct kvm_device_ops kvm_xics_ops = {
		.name = "kvm-xics",
		.create = kvmppc_xics_create,
		.destroy = kvmppc_xics_free,
		.set_attr = xics_set_attr,
		.get_attr = xics_get_attr,
		.has_attr = xics_has_attr,
		};

		int kvmppc_xics_connect_vcpu(struct kvm_device dev, struct kvm_vcpu vcpu,
		u32 xcpu)
		{
		struct kvmppc_xics *xics = dev->private;
		int r = -EBUSY;

		if (dev->ops != &kvm_xics_ops)
		return -EPERM;
		if (xics->kvm != vcpu->kvm)
		return -EPERM;
		if (vcpu->arch.irq_type)
		return -EBUSY;

		r = kvmppc_xics_create_icp(vcpu, xcpu);
		if (!r)
		vcpu->arch.irq_type = KVMPPC_IRQ_XICS;

		return r;
		}

		void kvmppc_xics_free_icp(struct kvm_vcpu *vcpu)
		{
		if (!vcpu->arch.icp)

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