diff options
Diffstat (limited to 'Documentation/virtual/kvm/api.txt')
| -rw-r--r-- | Documentation/virtual/kvm/api.txt | 108 |
1 files changed, 85 insertions, 23 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index e0fa0ea2b187..119358dfb742 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -219,19 +219,6 @@ allocation of vcpu ids. For example, if userspace wants single-threaded guest vcpus, it should make all vcpu ids be a multiple of the number of vcpus per vcore. -On powerpc using book3s_hv mode, the vcpus are mapped onto virtual -threads in one or more virtual CPU cores. (This is because the -hardware requires all the hardware threads in a CPU core to be in the -same partition.) The KVM_CAP_PPC_SMT capability indicates the number -of vcpus per virtual core (vcore). The vcore id is obtained by -dividing the vcpu id by the number of vcpus per vcore. The vcpus in a -given vcore will always be in the same physical core as each other -(though that might be a different physical core from time to time). -Userspace can control the threading (SMT) mode of the guest by its -allocation of vcpu ids. For example, if userspace wants -single-threaded guest vcpus, it should make all vcpu ids be a multiple -of the number of vcpus per vcore. - For virtual cpus that have been created with S390 user controlled virtual machines, the resulting vcpu fd can be memory mapped at page offset KVM_S390_SIE_PAGE_OFFSET in order to obtain a memory map of the virtual @@ -345,7 +332,7 @@ struct kvm_sregs { __u64 interrupt_bitmap[(KVM_NR_INTERRUPTS + 63) / 64]; }; -/* ppc -- see arch/powerpc/include/asm/kvm.h */ +/* ppc -- see arch/powerpc/include/uapi/asm/kvm.h */ interrupt_bitmap is a bitmap of pending external interrupts. At most one bit may be set. This interrupt has been acknowledged by the APIC @@ -892,12 +879,12 @@ It is recommended that the lower 21 bits of guest_phys_addr and userspace_addr be identical. This allows large pages in the guest to be backed by large pages in the host. -The flags field supports two flag, KVM_MEM_LOG_DIRTY_PAGES, which instructs -kvm to keep track of writes to memory within the slot. See KVM_GET_DIRTY_LOG -ioctl. The KVM_CAP_READONLY_MEM capability indicates the availability of the -KVM_MEM_READONLY flag. When this flag is set for a memory region, KVM only -allows read accesses. Writes will be posted to userspace as KVM_EXIT_MMIO -exits. +The flags field supports two flags: KVM_MEM_LOG_DIRTY_PAGES and +KVM_MEM_READONLY. The former can be set to instruct KVM to keep track of +writes to memory within the slot. See KVM_GET_DIRTY_LOG ioctl to know how to +use it. The latter can be set, if KVM_CAP_READONLY_MEM capability allows it, +to make a new slot read-only. In this case, writes to this memory will be +posted to userspace as KVM_EXIT_MMIO exits. When the KVM_CAP_SYNC_MMU capability is available, changes in the backing of the memory region are automatically reflected into the guest. For example, an @@ -931,7 +918,7 @@ documentation when it pops into existence). 4.37 KVM_ENABLE_CAP Capability: KVM_CAP_ENABLE_CAP -Architectures: ppc +Architectures: ppc, s390 Type: vcpu ioctl Parameters: struct kvm_enable_cap (in) Returns: 0 on success; -1 on error @@ -1792,6 +1779,7 @@ registers, find a list below: PPC | KVM_REG_PPC_VPA_SLB | 128 PPC | KVM_REG_PPC_VPA_DTL | 128 PPC | KVM_REG_PPC_EPCR | 32 + PPC | KVM_REG_PPC_EPR | 32 ARM registers are mapped using the lower 32 bits. The upper 16 of that is the register group type, or coprocessor number: @@ -2108,6 +2096,14 @@ KVM_S390_INT_VIRTIO (vm) - virtio external interrupt; external interrupt KVM_S390_INT_SERVICE (vm) - sclp external interrupt; sclp parameter in parm KVM_S390_INT_EMERGENCY (vcpu) - sigp emergency; source cpu in parm KVM_S390_INT_EXTERNAL_CALL (vcpu) - sigp external call; source cpu in parm +KVM_S390_INT_IO(ai,cssid,ssid,schid) (vm) - compound value to indicate an + I/O interrupt (ai - adapter interrupt; cssid,ssid,schid - subchannel); + I/O interruption parameters in parm (subchannel) and parm64 (intparm, + interruption subclass) +KVM_S390_MCHK (vm, vcpu) - machine check interrupt; cr 14 bits in parm, + machine check interrupt code in parm64 (note that + machine checks needing further payload are not + supported by this ioctl) Note that the vcpu ioctl is asynchronous to vcpu execution. @@ -2359,8 +2355,8 @@ 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 @@ -2463,6 +2459,41 @@ The possible hypercalls are defined in the Power Architecture Platform Requirements (PAPR) document available from www.power.org (free developer registration required to access it). + /* KVM_EXIT_S390_TSCH */ + struct { + __u16 subchannel_id; + __u16 subchannel_nr; + __u32 io_int_parm; + __u32 io_int_word; + __u32 ipb; + __u8 dequeued; + } s390_tsch; + +s390 specific. This exit occurs when KVM_CAP_S390_CSS_SUPPORT has been enabled +and TEST SUBCHANNEL was intercepted. If dequeued is set, a pending I/O +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]; }; @@ -2584,3 +2615,34 @@ For mmu types KVM_MMU_FSL_BOOKE_NOHV and KVM_MMU_FSL_BOOKE_HV: where "num_sets" is the tlb_sizes[] value divided by the tlb_ways[] value. - The tsize field of mas1 shall be set to 4K on TLB0, even though the hardware ignores this value for TLB0. + +6.4 KVM_CAP_S390_CSS_SUPPORT + +Architectures: s390 +Parameters: none +Returns: 0 on success; -1 on error + +This capability enables support for handling of channel I/O instructions. + +TEST PENDING INTERRUPTION and the interrupt portion of TEST SUBCHANNEL are +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. |