3 files changed, 183 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 4029943887a3..912b7df8215a 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -3255,6 +3255,141 @@ Otherwise, if the MCE is a corrected error, KVM will just
 store it in the corresponding bank (provided this bank is
 not holding a previously reported uncorrected error).
 
+4.107 KVM_S390_GET_CMMA_BITS
+
+Capability: KVM_CAP_S390_CMMA_MIGRATION
+Architectures: s390
+Type: vm ioctl
+Parameters: struct kvm_s390_cmma_log (in, out)
+Returns: 0 on success, a negative value on error
+
+This ioctl is used to get the values of the CMMA bits on the s390
+architecture. It is meant to be used in two scenarios:
+- During live migration to save the CMMA values. Live migration needs
+  to be enabled via the KVM_REQ_START_MIGRATION VM property.
+- To non-destructively peek at the CMMA values, with the flag
+  KVM_S390_CMMA_PEEK set.
+
+The ioctl takes parameters via the kvm_s390_cmma_log struct. The desired
+values are written to a buffer whose location is indicated via the "values"
+member in the kvm_s390_cmma_log struct.  The values in the input struct are
+also updated as needed.
+Each CMMA value takes up one byte.
+
+struct kvm_s390_cmma_log {
+	__u64 start_gfn;
+	__u32 count;
+	__u32 flags;
+	union {
+		__u64 remaining;
+		__u64 mask;
+	};
+	__u64 values;
+};
+
+start_gfn is the number of the first guest frame whose CMMA values are
+to be retrieved,
+
+count is the length of the buffer in bytes,
+
+values points to the buffer where the result will be written to.
+
+If count is greater than KVM_S390_SKEYS_MAX, then it is considered to be
+KVM_S390_SKEYS_MAX. KVM_S390_SKEYS_MAX is re-used for consistency with
+other ioctls.
+
+The result is written in the buffer pointed to by the field values, and
+the values of the input parameter are updated as follows.
+
+Depending on the flags, different actions are performed. The only
+supported flag so far is KVM_S390_CMMA_PEEK.
+
+The default behaviour if KVM_S390_CMMA_PEEK is not set is:
+start_gfn will indicate the first page frame whose CMMA bits were dirty.
+It is not necessarily the same as the one passed as input, as clean pages
+are skipped.
+
+count will indicate the number of bytes actually written in the buffer.
+It can (and very often will) be smaller than the input value, since the
+buffer is only filled until 16 bytes of clean values are found (which
+are then not copied in the buffer). Since a CMMA migration block needs
+the base address and the length, for a total of 16 bytes, we will send
+back some clean data if there is some dirty data afterwards, as long as
+the size of the clean data does not exceed the size of the header. This
+allows to minimize the amount of data to be saved or transferred over
+the network at the expense of more roundtrips to userspace. The next
+invocation of the ioctl will skip over all the clean values, saving
+potentially more than just the 16 bytes we found.
+
+If KVM_S390_CMMA_PEEK is set:
+the existing storage attributes are read even when not in migration
+mode, and no other action is performed;
+
+the output start_gfn will be equal to the input start_gfn,
+
+the output count will be equal to the input count, except if the end of
+memory has been reached.
+
+In both cases:
+the field "remaining" will indicate the total number of dirty CMMA values
+still remaining, or 0 if KVM_S390_CMMA_PEEK is set and migration mode is
+not enabled.
+
+mask is unused.
+
+values points to the userspace buffer where the result will be stored.
+
+This ioctl can fail with -ENOMEM if not enough memory can be allocated to
+complete the task, with -ENXIO if CMMA is not enabled, with -EINVAL if
+KVM_S390_CMMA_PEEK is not set but migration mode was not enabled, with
+-EFAULT if the userspace address is invalid or if no page table is
+present for the addresses (e.g. when using hugepages).
+
+4.108 KVM_S390_SET_CMMA_BITS
+
+Capability: KVM_CAP_S390_CMMA_MIGRATION
+Architectures: s390
+Type: vm ioctl
+Parameters: struct kvm_s390_cmma_log (in)
+Returns: 0 on success, a negative value on error
+
+This ioctl is used to set the values of the CMMA bits on the s390
+architecture. It is meant to be used during live migration to restore
+the CMMA values, but there are no restrictions on its use.
+The ioctl takes parameters via the kvm_s390_cmma_values struct.
+Each CMMA value takes up one byte.
+
+struct kvm_s390_cmma_log {
+	__u64 start_gfn;
+	__u32 count;
+	__u32 flags;
+	union {
+		__u64 remaining;
+		__u64 mask;
+	};
+	__u64 values;
+};
+
+start_gfn indicates the starting guest frame number,
+
+count indicates how many values are to be considered in the buffer,
+
+flags is not used and must be 0.
+
+mask indicates which PGSTE bits are to be considered.
+
+remaining is not used.
+
+values points to the buffer in userspace where to store the values.
+
+This ioctl can fail with -ENOMEM if not enough memory can be allocated to
+complete the task, with -ENXIO if CMMA is not enabled, with -EINVAL if
+the count field is too large (e.g. more than KVM_S390_CMMA_SIZE_MAX) or
+if the flags field was not 0, with -EFAULT if the userspace address is
+invalid, if invalid pages are written to (e.g. after the end of memory)
+or if no page table is present for the addresses (e.g. when using
+hugepages).
+
 5. The kvm_run structure
 ------------------------
 
diff --git a/Documentation/virtual/kvm/devices/s390_flic.txt b/Documentation/virtual/kvm/devices/s390_flic.txt
index c2518cea8ab4..2f1cbf1301d2 100644
--- a/Documentation/virtual/kvm/devices/s390_flic.txt
+++ b/Documentation/virtual/kvm/devices/s390_flic.txt
@@ -16,6 +16,7 @@ FLIC provides support to
 - register and modify adapter interrupt sources (KVM_DEV_FLIC_ADAPTER_*)
 - modify AIS (adapter-interruption-suppression) mode state (KVM_DEV_FLIC_AISM)
 - inject adapter interrupts on a specified adapter (KVM_DEV_FLIC_AIRQ_INJECT)
+- get/set all AIS mode states (KVM_DEV_FLIC_AISM_ALL)
 
 Groups:
   KVM_DEV_FLIC_ENQUEUE
@@ -136,6 +137,20 @@ struct kvm_s390_ais_req {
     an isc according to the adapter-interruption-suppression mode on condition
     that the AIS capability is enabled.
 
+  KVM_DEV_FLIC_AISM_ALL
+    Gets or sets the adapter-interruption-suppression mode for all ISCs. Takes
+    a kvm_s390_ais_all describing:
+
+struct kvm_s390_ais_all {
+       __u8 simm; /* Single-Interruption-Mode mask */
+       __u8 nimm; /* No-Interruption-Mode mask *
+};
+
+    simm contains Single-Interruption-Mode mask for all ISCs, nimm contains
+    No-Interruption-Mode mask for all ISCs. Each bit in simm and nimm corresponds
+    to an ISC (MSB0 bit 0 to ISC 0 and so on). The combination of simm bit and
+    nimm bit presents AIS mode for a ISC.
+
 Note: The KVM_SET_DEVICE_ATTR/KVM_GET_DEVICE_ATTR device ioctls executed on
 FLIC with an unknown group or attribute gives the error code EINVAL (instead of
 ENXIO, as specified in the API documentation). It is not possible to conclude
diff --git a/Documentation/virtual/kvm/devices/vm.txt b/Documentation/virtual/kvm/devices/vm.txt
index 575ccb022aac..903fc926860b 100644
--- a/Documentation/virtual/kvm/devices/vm.txt
+++ b/Documentation/virtual/kvm/devices/vm.txt
@@ -222,3 +222,36 @@ Allows user space to disable dea key wrapping, clearing the wrapping key.
 
 Parameters: none
 Returns:    0
+
+5. GROUP: KVM_S390_VM_MIGRATION
+Architectures: s390
+
+5.1. ATTRIBUTE: KVM_S390_VM_MIGRATION_STOP (w/o)
+
+Allows userspace to stop migration mode, needed for PGSTE migration.
+Setting this attribute when migration mode is not active will have no
+effects.
+
+Parameters: none
+Returns:    0
+
+5.2. ATTRIBUTE: KVM_S390_VM_MIGRATION_START (w/o)
+
+Allows userspace to start migration mode, needed for PGSTE migration.
+Setting this attribute when migration mode is already active will have
+no effects.
+
+Parameters: none
+Returns:    -ENOMEM if there is not enough free memory to start migration mode
+	    -EINVAL if the state of the VM is invalid (e.g. no memory defined)
+	    0 in case of success.
+
+5.3. ATTRIBUTE: KVM_S390_VM_MIGRATION_STATUS (r/o)
+
+Allows userspace to query the status of migration mode.
+
+Parameters: address of a buffer in user space to store the data (u64) to;
+	    the data itself is either 0 if migration mode is disabled or 1
+	    if it is enabled
+Returns:    -EFAULT if the given address is not accessible from kernel space
+	    0 in case of success.