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authorPaolo Bonzini <pbonzini@redhat.com>2015-04-07 18:10:03 +0200
committerPaolo Bonzini <pbonzini@redhat.com>2015-04-07 18:10:03 +0200
commit7f22b45d66b8e603e2e85e78f209531779f8b1cc (patch)
tree6abed0cec23ed9c6bb5a1e3dbfd15b4345fa9b62 /Documentation/virtual/kvm
parentMerge tag 'kvm-arm-for-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/... (diff)
parentKVM: s390: migrate vcpu interrupt state (diff)
downloadlinux-7f22b45d66b8e603e2e85e78f209531779f8b1cc.tar.xz
linux-7f22b45d66b8e603e2e85e78f209531779f8b1cc.zip
Merge tag 'kvm-s390-next-20150331' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
Features and fixes for 4.1 (kvm/next) 1. Assorted changes 1.1 allow more feature bits for the guest 1.2 Store breaking event address on program interrupts 2. Interrupt handling rework 2.1 Fix copy_to_user while holding a spinlock (cc stable) 2.2 Rework floating interrupts to follow the priorities 2.3 Allow to inject all local interrupts via new ioctl 2.4 allow to get/set the full local irq state, e.g. for migration and introspection
Diffstat (limited to 'Documentation/virtual/kvm')
-rw-r--r--Documentation/virtual/kvm/api.txt117
-rw-r--r--Documentation/virtual/kvm/devices/s390_flic.txt3
2 files changed, 120 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 57d25fdd3d7e..bc9f6fe44e27 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -2861,6 +2861,123 @@ single frame starting at start_gfn for count frames.
Note: If any architecturally invalid key value is found in the given data then
the ioctl will return -EINVAL.
+4.92 KVM_S390_IRQ
+
+Capability: KVM_CAP_S390_INJECT_IRQ
+Architectures: s390
+Type: vcpu ioctl
+Parameters: struct kvm_s390_irq (in)
+Returns: 0 on success, -1 on error
+Errors:
+ EINVAL: interrupt type is invalid
+ type is KVM_S390_SIGP_STOP and flag parameter is invalid value
+ type is KVM_S390_INT_EXTERNAL_CALL and code is bigger
+ than the maximum of VCPUs
+ EBUSY: type is KVM_S390_SIGP_SET_PREFIX and vcpu is not stopped
+ type is KVM_S390_SIGP_STOP and a stop irq is already pending
+ type is KVM_S390_INT_EXTERNAL_CALL and an external call interrupt
+ is already pending
+
+Allows to inject an interrupt to the guest.
+
+Using struct kvm_s390_irq as a parameter allows
+to inject additional payload which is not
+possible via KVM_S390_INTERRUPT.
+
+Interrupt parameters are passed via kvm_s390_irq:
+
+struct kvm_s390_irq {
+ __u64 type;
+ union {
+ struct kvm_s390_io_info io;
+ struct kvm_s390_ext_info ext;
+ struct kvm_s390_pgm_info pgm;
+ struct kvm_s390_emerg_info emerg;
+ struct kvm_s390_extcall_info extcall;
+ struct kvm_s390_prefix_info prefix;
+ struct kvm_s390_stop_info stop;
+ struct kvm_s390_mchk_info mchk;
+ char reserved[64];
+ } u;
+};
+
+type can be one of the following:
+
+KVM_S390_SIGP_STOP - sigp stop; parameter in .stop
+KVM_S390_PROGRAM_INT - program check; parameters in .pgm
+KVM_S390_SIGP_SET_PREFIX - sigp set prefix; parameters in .prefix
+KVM_S390_RESTART - restart; no parameters
+KVM_S390_INT_CLOCK_COMP - clock comparator interrupt; no parameters
+KVM_S390_INT_CPU_TIMER - CPU timer interrupt; no parameters
+KVM_S390_INT_EMERGENCY - sigp emergency; parameters in .emerg
+KVM_S390_INT_EXTERNAL_CALL - sigp external call; parameters in .extcall
+KVM_S390_MCHK - machine check interrupt; parameters in .mchk
+
+
+Note that the vcpu ioctl is asynchronous to vcpu execution.
+
+4.94 KVM_S390_GET_IRQ_STATE
+
+Capability: KVM_CAP_S390_IRQ_STATE
+Architectures: s390
+Type: vcpu ioctl
+Parameters: struct kvm_s390_irq_state (out)
+Returns: >= number of bytes copied into buffer,
+ -EINVAL if buffer size is 0,
+ -ENOBUFS if buffer size is too small to fit all pending interrupts,
+ -EFAULT if the buffer address was invalid
+
+This ioctl allows userspace to retrieve the complete state of all currently
+pending interrupts in a single buffer. Use cases include migration
+and introspection. The parameter structure contains the address of a
+userspace buffer and its length:
+
+struct kvm_s390_irq_state {
+ __u64 buf;
+ __u32 flags;
+ __u32 len;
+ __u32 reserved[4];
+};
+
+Userspace passes in the above struct and for each pending interrupt a
+struct kvm_s390_irq is copied to the provided buffer.
+
+If -ENOBUFS is returned the buffer provided was too small and userspace
+may retry with a bigger buffer.
+
+4.95 KVM_S390_SET_IRQ_STATE
+
+Capability: KVM_CAP_S390_IRQ_STATE
+Architectures: s390
+Type: vcpu ioctl
+Parameters: struct kvm_s390_irq_state (in)
+Returns: 0 on success,
+ -EFAULT if the buffer address was invalid,
+ -EINVAL for an invalid buffer length (see below),
+ -EBUSY if there were already interrupts pending,
+ errors occurring when actually injecting the
+ interrupt. See KVM_S390_IRQ.
+
+This ioctl allows userspace to set the complete state of all cpu-local
+interrupts currently pending for the vcpu. It is intended for restoring
+interrupt state after a migration. The input parameter is a userspace buffer
+containing a struct kvm_s390_irq_state:
+
+struct kvm_s390_irq_state {
+ __u64 buf;
+ __u32 len;
+ __u32 pad;
+};
+
+The userspace memory referenced by buf contains a struct kvm_s390_irq
+for each interrupt to be injected into the guest.
+If one of the interrupts could not be injected for some reason the
+ioctl aborts.
+
+len must be a multiple of sizeof(struct kvm_s390_irq). It must be > 0
+and it must not exceed (max_vcpus + 32) * sizeof(struct kvm_s390_irq),
+which is the maximum number of possibly pending cpu-local interrupts.
+
5. The kvm_run structure
------------------------
diff --git a/Documentation/virtual/kvm/devices/s390_flic.txt b/Documentation/virtual/kvm/devices/s390_flic.txt
index 4ceef53164b0..d1ad9d5cae46 100644
--- a/Documentation/virtual/kvm/devices/s390_flic.txt
+++ b/Documentation/virtual/kvm/devices/s390_flic.txt
@@ -27,6 +27,9 @@ Groups:
Copies all floating interrupts into a buffer provided by userspace.
When the buffer is too small it returns -ENOMEM, which is the indication
for userspace to try again with a bigger buffer.
+ -ENOBUFS is returned when the allocation of a kernelspace buffer has
+ failed.
+ -EFAULT is returned when copying data to userspace failed.
All interrupts remain pending, i.e. are not deleted from the list of
currently pending interrupts.
attr->addr contains the userspace address of the buffer into which all