KVM: s390: interprocessor communication via sigp
This patch introduces in-kernel handling of _some_ sigp interprocessor
signals (similar to ipi).
kvm_s390_handle_sigp() decodes the sigp instruction and calls individual
handlers depending on the operation requested:
- sigp sense tries to retrieve information such as existence or running state
of the remote cpu
- sigp emergency sends an external interrupt to the remove cpu
- sigp stop stops a remove cpu
- sigp stop store status stops a remote cpu, and stores its entire internal
state to the cpus lowcore
- sigp set arch sets the architecture mode of the remote cpu. setting to
ESAME (s390x 64bit) is accepted, setting to ESA/S390 (s390, 31 or 24 bit) is
denied, all others are passed to userland
- sigp set prefix sets the prefix register of a remote cpu
For implementation of this, the stop intercept indication starts to get reused
on purpose: a set of action bits defines what to do once a cpu gets stopped:
ACTION_STOP_ON_STOP really stops the cpu when a stop intercept is recognized
ACTION_STORE_ON_STOP stores the cpu status to lowcore when a stop intercept is
recognized
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/include/asm-s390/kvm_host.h b/include/asm-s390/kvm_host.h
index 2eaf6fe..1c829bd 100644
--- a/include/asm-s390/kvm_host.h
+++ b/include/asm-s390/kvm_host.h
@@ -128,6 +128,12 @@
u32 instruction_chsc;
u32 instruction_stsi;
u32 instruction_stfl;
+ u32 instruction_sigp_sense;
+ u32 instruction_sigp_emergency;
+ u32 instruction_sigp_stop;
+ u32 instruction_sigp_arch;
+ u32 instruction_sigp_prefix;
+ u32 instruction_sigp_restart;
};
struct io_info {
@@ -169,6 +175,10 @@
};
};
+/* for local_interrupt.action_flags */
+#define ACTION_STORE_ON_STOP 1
+#define ACTION_STOP_ON_STOP 2
+
struct local_interrupt {
spinlock_t lock;
struct list_head list;
@@ -176,6 +186,8 @@
struct float_interrupt *float_int;
int timer_due; /* event indicator for waitqueue below */
wait_queue_head_t wq;
+ atomic_t *cpuflags;
+ unsigned int action_bits;
};
struct float_interrupt {