diff options
Diffstat (limited to 'Documentation/virt/kvm')
| -rw-r--r-- | Documentation/virt/kvm/api.rst | 10 | ||||
| -rw-r--r-- | Documentation/virt/kvm/arm/hypercalls.rst | 98 | ||||
| -rw-r--r-- | Documentation/virt/kvm/index.rst | 1 | ||||
| -rw-r--r-- | Documentation/virt/kvm/loongarch/hypercalls.rst | 89 | ||||
| -rw-r--r-- | Documentation/virt/kvm/loongarch/index.rst | 10 |
5 files changed, 206 insertions, 2 deletions
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index fe722c5dada9..b3be87489108 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -2592,7 +2592,7 @@ Specifically: 0x6030 0000 0010 004a SPSR_ABT 64 spsr[KVM_SPSR_ABT] 0x6030 0000 0010 004c SPSR_UND 64 spsr[KVM_SPSR_UND] 0x6030 0000 0010 004e SPSR_IRQ 64 spsr[KVM_SPSR_IRQ] - 0x6060 0000 0010 0050 SPSR_FIQ 64 spsr[KVM_SPSR_FIQ] + 0x6030 0000 0010 0050 SPSR_FIQ 64 spsr[KVM_SPSR_FIQ] 0x6040 0000 0010 0054 V0 128 fp_regs.vregs[0] [1]_ 0x6040 0000 0010 0058 V1 128 fp_regs.vregs[1] [1]_ ... @@ -6368,7 +6368,7 @@ a single guest_memfd file, but the bound ranges must not overlap). See KVM_SET_USER_MEMORY_REGION2 for additional details. 4.143 KVM_PRE_FAULT_MEMORY ------------------------- +--------------------------- :Capability: KVM_CAP_PRE_FAULT_MEMORY :Architectures: none @@ -6405,6 +6405,12 @@ for the current vCPU state. KVM maps memory as if the vCPU generated a stage-2 read page fault, e.g. faults in memory as needed, but doesn't break CoW. However, KVM does not mark any newly created stage-2 PTE as Accessed. +In the case of confidential VM types where there is an initial set up of +private guest memory before the guest is 'finalized'/measured, this ioctl +should only be issued after completing all the necessary setup to put the +guest into a 'finalized' state so that the above semantics can be reliably +ensured. + In some cases, multiple vCPUs might share the page tables. In this case, the ioctl can be called in parallel. diff --git a/Documentation/virt/kvm/arm/hypercalls.rst b/Documentation/virt/kvm/arm/hypercalls.rst index 17be111f493f..af7bc2c2e0cb 100644 --- a/Documentation/virt/kvm/arm/hypercalls.rst +++ b/Documentation/virt/kvm/arm/hypercalls.rst @@ -44,3 +44,101 @@ Provides a discovery mechanism for other KVM/arm64 hypercalls. ---------------------------------------- See ptp_kvm.rst + +``ARM_SMCCC_KVM_FUNC_HYP_MEMINFO`` +---------------------------------- + +Query the memory protection parameters for a pKVM protected virtual machine. + ++---------------------+-------------------------------------------------------------+ +| Presence: | Optional; pKVM protected guests only. | ++---------------------+-------------------------------------------------------------+ +| Calling convention: | HVC64 | ++---------------------+----------+--------------------------------------------------+ +| Function ID: | (uint32) | 0xC6000002 | ++---------------------+----------+----+---------------------------------------------+ +| Arguments: | (uint64) | R1 | Reserved / Must be zero | +| +----------+----+---------------------------------------------+ +| | (uint64) | R2 | Reserved / Must be zero | +| +----------+----+---------------------------------------------+ +| | (uint64) | R3 | Reserved / Must be zero | ++---------------------+----------+----+---------------------------------------------+ +| Return Values: | (int64) | R0 | ``INVALID_PARAMETER (-3)`` on error, else | +| | | | memory protection granule in bytes | ++---------------------+----------+----+---------------------------------------------+ + +``ARM_SMCCC_KVM_FUNC_MEM_SHARE`` +-------------------------------- + +Share a region of memory with the KVM host, granting it read, write and execute +permissions. The size of the region is equal to the memory protection granule +advertised by ``ARM_SMCCC_KVM_FUNC_HYP_MEMINFO``. + ++---------------------+-------------------------------------------------------------+ +| Presence: | Optional; pKVM protected guests only. | ++---------------------+-------------------------------------------------------------+ +| Calling convention: | HVC64 | ++---------------------+----------+--------------------------------------------------+ +| Function ID: | (uint32) | 0xC6000003 | ++---------------------+----------+----+---------------------------------------------+ +| Arguments: | (uint64) | R1 | Base IPA of memory region to share | +| +----------+----+---------------------------------------------+ +| | (uint64) | R2 | Reserved / Must be zero | +| +----------+----+---------------------------------------------+ +| | (uint64) | R3 | Reserved / Must be zero | ++---------------------+----------+----+---------------------------------------------+ +| Return Values: | (int64) | R0 | ``SUCCESS (0)`` | +| | | +---------------------------------------------+ +| | | | ``INVALID_PARAMETER (-3)`` | ++---------------------+----------+----+---------------------------------------------+ + +``ARM_SMCCC_KVM_FUNC_MEM_UNSHARE`` +---------------------------------- + +Revoke access permission from the KVM host to a memory region previously shared +with ``ARM_SMCCC_KVM_FUNC_MEM_SHARE``. The size of the region is equal to the +memory protection granule advertised by ``ARM_SMCCC_KVM_FUNC_HYP_MEMINFO``. + ++---------------------+-------------------------------------------------------------+ +| Presence: | Optional; pKVM protected guests only. | ++---------------------+-------------------------------------------------------------+ +| Calling convention: | HVC64 | ++---------------------+----------+--------------------------------------------------+ +| Function ID: | (uint32) | 0xC6000004 | ++---------------------+----------+----+---------------------------------------------+ +| Arguments: | (uint64) | R1 | Base IPA of memory region to unshare | +| +----------+----+---------------------------------------------+ +| | (uint64) | R2 | Reserved / Must be zero | +| +----------+----+---------------------------------------------+ +| | (uint64) | R3 | Reserved / Must be zero | ++---------------------+----------+----+---------------------------------------------+ +| Return Values: | (int64) | R0 | ``SUCCESS (0)`` | +| | | +---------------------------------------------+ +| | | | ``INVALID_PARAMETER (-3)`` | ++---------------------+----------+----+---------------------------------------------+ + +``ARM_SMCCC_KVM_FUNC_MMIO_GUARD`` +---------------------------------- + +Request that a given memory region is handled as MMIO by the hypervisor, +allowing accesses to this region to be emulated by the KVM host. The size of the +region is equal to the memory protection granule advertised by +``ARM_SMCCC_KVM_FUNC_HYP_MEMINFO``. + ++---------------------+-------------------------------------------------------------+ +| Presence: | Optional; pKVM protected guests only. | ++---------------------+-------------------------------------------------------------+ +| Calling convention: | HVC64 | ++---------------------+----------+--------------------------------------------------+ +| Function ID: | (uint32) | 0xC6000007 | ++---------------------+----------+----+---------------------------------------------+ +| Arguments: | (uint64) | R1 | Base IPA of MMIO memory region | +| +----------+----+---------------------------------------------+ +| | (uint64) | R2 | Reserved / Must be zero | +| +----------+----+---------------------------------------------+ +| | (uint64) | R3 | Reserved / Must be zero | ++---------------------+----------+----+---------------------------------------------+ +| Return Values: | (int64) | R0 | ``SUCCESS (0)`` | +| | | +---------------------------------------------+ +| | | | ``INVALID_PARAMETER (-3)`` | ++---------------------+----------+----+---------------------------------------------+ diff --git a/Documentation/virt/kvm/index.rst b/Documentation/virt/kvm/index.rst index ad13ec55ddfe..9ca5a45c2140 100644 --- a/Documentation/virt/kvm/index.rst +++ b/Documentation/virt/kvm/index.rst @@ -14,6 +14,7 @@ KVM s390/index ppc-pv x86/index + loongarch/index locking vcpu-requests diff --git a/Documentation/virt/kvm/loongarch/hypercalls.rst b/Documentation/virt/kvm/loongarch/hypercalls.rst new file mode 100644 index 000000000000..2d6b94031f1b --- /dev/null +++ b/Documentation/virt/kvm/loongarch/hypercalls.rst @@ -0,0 +1,89 @@ +.. SPDX-License-Identifier: GPL-2.0 + +=================================== +The LoongArch paravirtual interface +=================================== + +KVM hypercalls use the HVCL instruction with code 0x100 and the hypercall +number is put in a0. Up to five arguments may be placed in registers a1 - a5. +The return value is placed in v0 (an alias of a0). + +Source code for this interface can be found in arch/loongarch/kvm*. + +Querying for existence +====================== + +To determine if the host is running on KVM, we can utilize the cpucfg() +function at index CPUCFG_KVM_BASE (0x40000000). + +The CPUCFG_KVM_BASE range, spanning from 0x40000000 to 0x400000FF, The +CPUCFG_KVM_BASE range between 0x40000000 - 0x400000FF is marked as reserved. +Consequently, all current and future processors will not implement any +feature within this range. + +On a KVM-virtualized Linux system, a read operation on cpucfg() at index +CPUCFG_KVM_BASE (0x40000000) returns the magic string 'KVM\0'. + +Once you have determined that your host is running on a paravirtualization- +capable KVM, you may now use hypercalls as described below. + +KVM hypercall ABI +================= + +The KVM hypercall ABI is simple, with one scratch register a0 (v0) and at most +five generic registers (a1 - a5) used as input parameters. The FP (Floating- +point) and vector registers are not utilized as input registers and must +remain unmodified during a hypercall. + +Hypercall functions can be inlined as it only uses one scratch register. + +The parameters are as follows: + + ======== ================= ================ + Register IN OUT + ======== ================= ================ + a0 function number Return code + a1 1st parameter - + a2 2nd parameter - + a3 3rd parameter - + a4 4th parameter - + a5 5th parameter - + ======== ================= ================ + +The return codes may be one of the following: + + ==== ========================= + Code Meaning + ==== ========================= + 0 Success + -1 Hypercall not implemented + -2 Bad Hypercall parameter + ==== ========================= + +KVM Hypercalls Documentation +============================ + +The template for each hypercall is as follows: + +1. Hypercall name +2. Purpose + +1. KVM_HCALL_FUNC_IPI +------------------------ + +:Purpose: Send IPIs to multiple vCPUs. + +- a0: KVM_HCALL_FUNC_IPI +- a1: Lower part of the bitmap for destination physical CPUIDs +- a2: Higher part of the bitmap for destination physical CPUIDs +- a3: The lowest physical CPUID in the bitmap + +The hypercall lets a guest send multiple IPIs (Inter-Process Interrupts) with +at most 128 destinations per hypercall. The destinations are represented in a +bitmap contained in the first two input registers (a1 and a2). + +Bit 0 of a1 corresponds to the physical CPUID in the third input register (a3) +and bit 1 corresponds to the physical CPUID in a3+1, and so on. + +PV IPI on LoongArch includes both PV IPI multicast sending and PV IPI receiving, +and SWI is used for PV IPI inject since there is no VM-exits accessing SWI registers. diff --git a/Documentation/virt/kvm/loongarch/index.rst b/Documentation/virt/kvm/loongarch/index.rst new file mode 100644 index 000000000000..83387b4c5345 --- /dev/null +++ b/Documentation/virt/kvm/loongarch/index.rst @@ -0,0 +1,10 @@ +.. SPDX-License-Identifier: GPL-2.0 + +========================= +KVM for LoongArch systems +========================= + +.. toctree:: + :maxdepth: 2 + + hypercalls.rst |