diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/virtual/kvm/api.txt | 40 |
1 files changed, 38 insertions, 2 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 4fc2bfcb16d5..a98ed09269d7 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -2246,8 +2246,8 @@ executed a memory-mapped I/O instruction which could not be satisfied by kvm. The 'data' member contains the written data if 'is_write' is true, and should be filled by application code otherwise. -NOTE: For KVM_EXIT_IO, KVM_EXIT_MMIO, KVM_EXIT_OSI, KVM_EXIT_DCR - and KVM_EXIT_PAPR the corresponding +NOTE: For KVM_EXIT_IO, KVM_EXIT_MMIO, KVM_EXIT_OSI, KVM_EXIT_DCR, + KVM_EXIT_PAPR and KVM_EXIT_EPR the corresponding operations are complete (and guest state is consistent) only after userspace has re-entered the kernel with KVM_RUN. The kernel side will first finish incomplete operations and then check for pending signals. Userspace @@ -2366,6 +2366,25 @@ interrupt for the target subchannel has been dequeued and subchannel_id, subchannel_nr, io_int_parm and io_int_word contain the parameters for that interrupt. ipb is needed for instruction parameter decoding. + /* KVM_EXIT_EPR */ + struct { + __u32 epr; + } epr; + +On FSL BookE PowerPC chips, the interrupt controller has a fast patch +interrupt acknowledge path to the core. When the core successfully +delivers an interrupt, it automatically populates the EPR register with +the interrupt vector number and acknowledges the interrupt inside +the interrupt controller. + +In case the interrupt controller lives in user space, we need to do +the interrupt acknowledge cycle through it to fetch the next to be +delivered interrupt vector using this exit. + +It gets triggered whenever both KVM_CAP_PPC_EPR are enabled and an +external interrupt has just been delivered into the guest. User space +should put the acknowledged interrupt vector into the 'epr' field. + /* Fix the size of the union. */ char padding[256]; }; @@ -2501,3 +2520,20 @@ handled in-kernel, while the other I/O instructions are passed to userspace. When this capability is enabled, KVM_EXIT_S390_TSCH will occur on TEST SUBCHANNEL intercepts. + +6.5 KVM_CAP_PPC_EPR + +Architectures: ppc +Parameters: args[0] defines whether the proxy facility is active +Returns: 0 on success; -1 on error + +This capability enables or disables the delivery of interrupts through the +external proxy facility. + +When enabled (args[0] != 0), every time the guest gets an external interrupt +delivered, it automatically exits into user space with a KVM_EXIT_EPR exit +to receive the topmost interrupt vector. + +When disabled (args[0] == 0), behavior is as if this facility is unsupported. + +When this capability is enabled, KVM_EXIT_EPR can occur. |