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authorHeiko Carstens <heiko.carstens@de.ibm.com>2008-03-25 18:47:20 +0100
committerAvi Kivity <avi@qumranet.com>2008-04-27 12:00:42 +0300
commitb0c632db637d68ad39d9f97f452ce176253f5f4e (patch)
tree770d68c17cbcabc1543d1e9125669130fcf4fee4 /arch/s390/kvm/sie64a.S
parent8a88ac6183975c73c65b45f365f6f3b875c1348b (diff)
KVM: s390: arch backend for the kvm kernel module
This patch contains the port of Qumranet's kvm kernel module to IBM zSeries (aka s390x, mainframe) architecture. It uses the mainframe's virtualization instruction SIE to run virtual machines with up to 64 virtual CPUs each. This port is only usable on 64bit host kernels, and can only run 64bit guest kernels. However, running 31bit applications in guest userspace is possible. The following source files are introduced by this patch arch/s390/kvm/kvm-s390.c similar to arch/x86/kvm/x86.c, this implements all arch callbacks for kvm. __vcpu_run calls back into sie64a to enter the guest machine context arch/s390/kvm/sie64a.S assembler function sie64a, which enters guest context via SIE, and switches world before and after that include/asm-s390/kvm_host.h contains all vital data structures needed to run virtual machines on the mainframe include/asm-s390/kvm.h defines kvm_regs and friends for user access to guest register content arch/s390/kvm/gaccess.h functions similar to uaccess to access guest memory arch/s390/kvm/kvm-s390.h header file for kvm-s390 internals, extended by later patches Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Diffstat (limited to 'arch/s390/kvm/sie64a.S')
-rw-r--r--arch/s390/kvm/sie64a.S47
1 files changed, 47 insertions, 0 deletions
diff --git a/arch/s390/kvm/sie64a.S b/arch/s390/kvm/sie64a.S
new file mode 100644
index 00000000000..934fd6a885f
--- /dev/null
+++ b/arch/s390/kvm/sie64a.S
@@ -0,0 +1,47 @@
+/*
+ * sie64a.S - low level sie call
+ *
+ * Copyright IBM Corp. 2008
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ *
+ * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
+ */
+
+#include <linux/errno.h>
+#include <asm/asm-offsets.h>
+
+SP_R5 = 5 * 8 # offset into stackframe
+SP_R6 = 6 * 8
+
+/*
+ * sie64a calling convention:
+ * %r2 pointer to sie control block
+ * %r3 guest register save area
+ */
+ .globl sie64a
+sie64a:
+ lgr %r5,%r3
+ stmg %r5,%r14,SP_R5(%r15) # save register on entry
+ lgr %r14,%r2 # pointer to sie control block
+ lmg %r0,%r13,0(%r3) # load guest gprs 0-13
+sie_inst:
+ sie 0(%r14)
+ lg %r14,SP_R5(%r15)
+ stmg %r0,%r13,0(%r14) # save guest gprs 0-13
+ lghi %r2,0
+ lmg %r6,%r14,SP_R6(%r15)
+ br %r14
+
+sie_err:
+ lg %r14,SP_R5(%r15)
+ stmg %r0,%r13,0(%r14) # save guest gprs 0-13
+ lghi %r2,-EFAULT
+ lmg %r6,%r14,SP_R6(%r15)
+ br %r14
+
+ .section __ex_table,"a"
+ .quad sie_inst,sie_err
+ .previous