kvm: provide synchronous registers in kvm_run

kvm: provide synchronous registers in kvm_run

[Christian Borntraeger]

Avi, Marcelo,

here is the next version of the sync register patch series.

[PATCH 1/4] kvm: provide synchronous registers in kvm_run

[Christian Borntraeger]

On some cpus the overhead for virtualization instructions is in the same
range as a system call. Having to call multiple ioctls to get set registers
will make certain userspace handled exits more expensive than necessary.
Lets provide a section in kvm_run that works as a shared save area
for guest registers.
We also provide two 64bit flags fields (architecture specific), that will
specify
1. which parts of these fields are valid.
2. which registers were modified by userspace

Each bit for these flag fields will define a group of registers (like
general purpose) or a single register.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 Documentation/virtual/kvm/api.txt |   23 +++++++++++++++++++++++
 arch/ia64/include/asm/kvm.h       |    4 ++++
 arch/powerpc/include/asm/kvm.h    |    4 ++++
 arch/s390/include/asm/kvm.h       |    3 +++
 arch/x86/include/asm/kvm.h        |    4 ++++
 include/linux/kvm.h               |   15 +++++++++++++++
 6 files changed, 53 insertions(+), 0 deletions(-)

diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index a67fb35..7ca6962 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -1771,6 +1771,29 @@ developer registration required to access it).
 		/* Fix the size of the union. */
 		char padding[256];
 	};
+
+	/*
+	 * shared registers between kvm and userspace.
+	 * kvm_valid_regs specifies the register classes set by the host
+	 * kvm_dirty_regs specified the register classes dirtied by userspace
+	 * struct kvm_sync_regs is architecture specific, as well as the
+	 * bits for kvm_valid_regs and kvm_dirty_regs
+	 */
+	__u64 kvm_valid_regs;
+	__u64 kvm_dirty_regs;
+	union {
+		struct kvm_sync_regs regs;
+		char padding[1024];
+	} s;
+
+If KVM_CAP_SYNC_REGS is defined, these fields allow userspace to access
+certain guest registers without having to call SET/GET_*REGS. Thus we can
+avoid some system call overhead if userspace has to handle the exit.
+Userspace can query the validity of the structure by checking
+kvm_valid_regs for specific bits. These bits are architecture specific
+and usually define the validity of a groups of registers. (e.g. one bit
+ for general purpose registers)
+
 };
 
 6. Capabilities that can be enabled
diff --git a/arch/ia64/include/asm/kvm.h b/arch/ia64/include/asm/kvm.h
index bc90c75..b9f82c8 100644
--- a/arch/ia64/include/asm/kvm.h
+++ b/arch/ia64/include/asm/kvm.h
@@ -261,4 +261,8 @@ struct kvm_debug_exit_arch {
 struct kvm_guest_debug_arch {
 };
 
+/* definition of registers in kvm_run */
+struct kvm_sync_regs {
+};
+
 #endif
diff --git a/arch/powerpc/include/asm/kvm.h b/arch/powerpc/include/asm/kvm.h
index f7727d9..7d9d4de 100644
--- a/arch/powerpc/include/asm/kvm.h
+++ b/arch/powerpc/include/asm/kvm.h
@@ -265,6 +265,10 @@ struct kvm_debug_exit_arch {
 struct kvm_guest_debug_arch {
 };
 
+/* definition of registers in kvm_run */
+struct kvm_sync_regs {
+};
+
 #define KVM_REG_MASK		0x001f
 #define KVM_REG_EXT_MASK	0xffe0
 #define KVM_REG_GPR		0x0000
diff --git a/arch/s390/include/asm/kvm.h b/arch/s390/include/asm/kvm.h
index 82b32a1..325560a 100644
--- a/arch/s390/include/asm/kvm.h
+++ b/arch/s390/include/asm/kvm.h
@@ -41,4 +41,7 @@ struct kvm_debug_exit_arch {
 struct kvm_guest_debug_arch {
 };
 
+/* definition of registers in kvm_run */
+struct kvm_sync_regs {
+};
 #endif
diff --git a/arch/x86/include/asm/kvm.h b/arch/x86/include/asm/kvm.h
index 4d8dcbd..e7d1c19 100644
--- a/arch/x86/include/asm/kvm.h
+++ b/arch/x86/include/asm/kvm.h
@@ -321,4 +321,8 @@ struct kvm_xcrs {
 	__u64 padding[16];
 };
 
+/* definition of registers in kvm_run */
+struct kvm_sync_regs {
+};
+
 #endif /* _ASM_X86_KVM_H */
diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index 6cf048d..245bcb3 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -279,6 +279,20 @@ struct kvm_run {
 		/* Fix the size of the union. */
 		char padding[256];
 	};
+
+	/*
+	 * shared registers between kvm and userspace.
+	 * kvm_valid_regs specifies the register classes set by the host
+	 * kvm_dirty_regs specified the register classes dirtied by userspace
+	 * struct kvm_sync_regs is architecture specific, as well as the
+	 * bits for kvm_valid_regs and kvm_dirty_regs
+	 */
+	__u64 kvm_valid_regs;
+	__u64 kvm_dirty_regs;
+	union {
+		struct kvm_sync_regs regs;
+		char padding[1024];
+	} s;
 };
 
 /* for KVM_REGISTER_COALESCED_MMIO / KVM_UNREGISTER_COALESCED_MMIO */
@@ -570,6 +584,7 @@ struct kvm_ppc_pvinfo {
 #define KVM_CAP_S390_GMAP 71
 #define KVM_CAP_TSC_DEADLINE_TIMER 72
 #define KVM_CAP_S390_UCONTROL 73
+#define KVM_CAP_SYNC_REGS 74
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
-- 
1.7.8.2

[PATCH 2/4] kvm-s390: provide the prefix register via kvm_run

[Christian Borntraeger]

Add the prefix register to the synced register field in kvm_run.
While we need the prefix register most of the time read-only, this
patch also adds handling for guest dirtying of the prefix register.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 arch/s390/include/asm/kvm.h |    2 ++
 arch/s390/kvm/kvm-s390.c    |    7 +++++++
 2 files changed, 9 insertions(+), 0 deletions(-)

diff --git a/arch/s390/include/asm/kvm.h b/arch/s390/include/asm/kvm.h
index 325560a..9fc328c 100644
--- a/arch/s390/include/asm/kvm.h
+++ b/arch/s390/include/asm/kvm.h
@@ -41,7 +41,9 @@ struct kvm_debug_exit_arch {
 struct kvm_guest_debug_arch {
 };
 
+#define KVM_SYNC_PREFIX (1UL << 0)
 /* definition of registers in kvm_run */
 struct kvm_sync_regs {
+	__u64 prefix;	/* prefix register */
 };
 #endif
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 1868b89..6962c1b 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -132,6 +132,7 @@ int kvm_dev_ioctl_check_extension(long ext)
 #ifdef CONFIG_KVM_S390_UCONTROL
 	case KVM_CAP_S390_UCONTROL:
 #endif
+	case KVM_CAP_SYNC_REGS:
 		r = 1;
 		break;
 	default:
@@ -288,6 +289,7 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
 	}
 
 	vcpu->arch.gmap = vcpu->kvm->arch.gmap;
+	vcpu->run->kvm_valid_regs = KVM_SYNC_PREFIX;
 	return 0;
 }
 
@@ -572,6 +574,10 @@ rerun_vcpu:
 
 	vcpu->arch.sie_block->gpsw.mask = kvm_run->psw_mask;
 	vcpu->arch.sie_block->gpsw.addr = kvm_run->psw_addr;
+	if (kvm_run->kvm_dirty_regs & KVM_SYNC_PREFIX) {
+		kvm_run->kvm_dirty_regs &= ~KVM_SYNC_PREFIX;
+		kvm_s390_set_prefix(vcpu, kvm_run->s.regs.prefix);
+	}
 
 	might_fault();
 
@@ -620,6 +626,7 @@ rerun_vcpu:
 
 	kvm_run->psw_mask     = vcpu->arch.sie_block->gpsw.mask;
 	kvm_run->psw_addr     = vcpu->arch.sie_block->gpsw.addr;
+	kvm_run->s.regs.prefix = vcpu->arch.sie_block->prefix;
 
 	if (vcpu->sigset_active)
 		sigprocmask(SIG_SETMASK, &sigsaved, NULL);
-- 
1.7.8.2

[PATCH 3/4] kvm-s390: provide general purpose guest registers via kvm_run

[Christian Borntraeger]

This patch adds the general purpose registers to the kvm_run structure.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 arch/s390/include/asm/kvm.h      |    2 ++
 arch/s390/include/asm/kvm_host.h |    3 +--
 arch/s390/kvm/diag.c             |    6 +++---
 arch/s390/kvm/intercept.c        |    4 ++--
 arch/s390/kvm/kvm-s390.c         |   14 +++++++-------
 arch/s390/kvm/priv.c             |   24 ++++++++++++------------
 arch/s390/kvm/sigp.c             |   20 ++++++++++----------
 7 files changed, 37 insertions(+), 36 deletions(-)

diff --git a/arch/s390/include/asm/kvm.h b/arch/s390/include/asm/kvm.h
index 9fc328c..420dbb7 100644
--- a/arch/s390/include/asm/kvm.h
+++ b/arch/s390/include/asm/kvm.h
@@ -42,8 +42,10 @@ struct kvm_guest_debug_arch {
 };
 
 #define KVM_SYNC_PREFIX (1UL << 0)
+#define KVM_SYNC_GPRS   (1UL << 1)
 /* definition of registers in kvm_run */
 struct kvm_sync_regs {
 	__u64 prefix;	/* prefix register */
+	__u64 gprs[16];	/* general purpose registers */
 };
 #endif
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index e34fb2b..ed843ca 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -228,7 +228,6 @@ struct kvm_s390_float_interrupt {
 
 struct kvm_vcpu_arch {
 	struct kvm_s390_sie_block *sie_block;
-	unsigned long	  guest_gprs[16];
 	s390_fp_regs      host_fpregs;
 	unsigned int      host_acrs[NUM_ACRS];
 	s390_fp_regs      guest_fpregs;
@@ -254,5 +253,5 @@ struct kvm_arch{
 	struct gmap *gmap;
 };
 
-extern int sie64a(struct kvm_s390_sie_block *, unsigned long *);
+extern int sie64a(struct kvm_s390_sie_block *, u64 *);
 #endif
diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c
index 8943e82..a353f0e 100644
--- a/arch/s390/kvm/diag.c
+++ b/arch/s390/kvm/diag.c
@@ -20,8 +20,8 @@ static int diag_release_pages(struct kvm_vcpu *vcpu)
 	unsigned long start, end;
 	unsigned long prefix  = vcpu->arch.sie_block->prefix;
 
-	start = vcpu->arch.guest_gprs[(vcpu->arch.sie_block->ipa & 0xf0) >> 4];
-	end = vcpu->arch.guest_gprs[vcpu->arch.sie_block->ipa & 0xf] + 4096;
+	start = vcpu->run->s.regs.gprs[(vcpu->arch.sie_block->ipa & 0xf0) >> 4];
+	end = vcpu->run->s.regs.gprs[vcpu->arch.sie_block->ipa & 0xf] + 4096;
 
 	if (start & ~PAGE_MASK || end & ~PAGE_MASK || start > end
 	    || start < 2 * PAGE_SIZE)
@@ -56,7 +56,7 @@ static int __diag_time_slice_end(struct kvm_vcpu *vcpu)
 static int __diag_ipl_functions(struct kvm_vcpu *vcpu)
 {
 	unsigned int reg = vcpu->arch.sie_block->ipa & 0xf;
-	unsigned long subcode = vcpu->arch.guest_gprs[reg] & 0xffff;
+	unsigned long subcode = vcpu->run->s.regs.gprs[reg] & 0xffff;
 
 	VCPU_EVENT(vcpu, 5, "diag ipl functions, subcode %lx", subcode);
 	switch (subcode) {
diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c
index 0243454..776ef83 100644
--- a/arch/s390/kvm/intercept.c
+++ b/arch/s390/kvm/intercept.c
@@ -36,7 +36,7 @@ static int handle_lctlg(struct kvm_vcpu *vcpu)
 
 	useraddr = disp2;
 	if (base2)
-		useraddr += vcpu->arch.guest_gprs[base2];
+		useraddr += vcpu->run->s.regs.gprs[base2];
 
 	if (useraddr & 7)
 		return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
@@ -75,7 +75,7 @@ static int handle_lctl(struct kvm_vcpu *vcpu)
 
 	useraddr = disp2;
 	if (base2)
-		useraddr += vcpu->arch.guest_gprs[base2];
+		useraddr += vcpu->run->s.regs.gprs[base2];
 
 	if (useraddr & 3)
 		return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 6962c1b..80b12ba 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -289,7 +289,7 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
 	}
 
 	vcpu->arch.gmap = vcpu->kvm->arch.gmap;
-	vcpu->run->kvm_valid_regs = KVM_SYNC_PREFIX;
+	vcpu->run->kvm_valid_regs = KVM_SYNC_PREFIX | KVM_SYNC_GPRS;
 	return 0;
 }
 
@@ -428,13 +428,13 @@ static int kvm_arch_vcpu_ioctl_initial_reset(struct kvm_vcpu *vcpu)
 
 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 {
-	memcpy(&vcpu->arch.guest_gprs, &regs->gprs, sizeof(regs->gprs));
+	memcpy(&vcpu->run->s.regs.gprs, &regs->gprs, sizeof(regs->gprs));
 	return 0;
 }
 
 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 {
-	memcpy(&regs->gprs, &vcpu->arch.guest_gprs, sizeof(regs->gprs));
+	memcpy(&regs->gprs, &vcpu->run->s.regs.gprs, sizeof(regs->gprs));
 	return 0;
 }
 
@@ -511,7 +511,7 @@ static int __vcpu_run(struct kvm_vcpu *vcpu)
 {
 	int rc;
 
-	memcpy(&vcpu->arch.sie_block->gg14, &vcpu->arch.guest_gprs[14], 16);
+	memcpy(&vcpu->arch.sie_block->gg14, &vcpu->run->s.regs.gprs[14], 16);
 
 	if (need_resched())
 		schedule();
@@ -528,7 +528,7 @@ static int __vcpu_run(struct kvm_vcpu *vcpu)
 	local_irq_enable();
 	VCPU_EVENT(vcpu, 6, "entering sie flags %x",
 		   atomic_read(&vcpu->arch.sie_block->cpuflags));
-	rc = sie64a(vcpu->arch.sie_block, vcpu->arch.guest_gprs);
+	rc = sie64a(vcpu->arch.sie_block, vcpu->run->s.regs.gprs);
 	if (rc) {
 		if (kvm_is_ucontrol(vcpu->kvm)) {
 			rc = SIE_INTERCEPT_UCONTROL;
@@ -544,7 +544,7 @@ static int __vcpu_run(struct kvm_vcpu *vcpu)
 	kvm_guest_exit();
 	local_irq_enable();
 
-	memcpy(&vcpu->arch.guest_gprs[14], &vcpu->arch.sie_block->gg14, 16);
+	memcpy(&vcpu->run->s.regs.gprs[14], &vcpu->arch.sie_block->gg14, 16);
 	return rc;
 }
 
@@ -673,7 +673,7 @@ int kvm_s390_vcpu_store_status(struct kvm_vcpu *vcpu, unsigned long addr)
 		return -EFAULT;
 
 	if (__guestcopy(vcpu, addr + offsetof(struct save_area, gp_regs),
-			vcpu->arch.guest_gprs, 128, prefix))
+			vcpu->run->s.regs.gprs, 128, prefix))
 		return -EFAULT;
 
 	if (__guestcopy(vcpu, addr + offsetof(struct save_area, psw),
diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
index 9c83b8a..e5a45db 100644
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -33,7 +33,7 @@ static int handle_set_prefix(struct kvm_vcpu *vcpu)
 
 	operand2 = disp2;
 	if (base2)
-		operand2 += vcpu->arch.guest_gprs[base2];
+		operand2 += vcpu->run->s.regs.gprs[base2];
 
 	/* must be word boundary */
 	if (operand2 & 3) {
@@ -73,7 +73,7 @@ static int handle_store_prefix(struct kvm_vcpu *vcpu)
 	vcpu->stat.instruction_stpx++;
 	operand2 = disp2;
 	if (base2)
-		operand2 += vcpu->arch.guest_gprs[base2];
+		operand2 += vcpu->run->s.regs.gprs[base2];
 
 	/* must be word boundary */
 	if (operand2 & 3) {
@@ -105,7 +105,7 @@ static int handle_store_cpu_address(struct kvm_vcpu *vcpu)
 	vcpu->stat.instruction_stap++;
 	useraddr = disp2;
 	if (base2)
-		useraddr += vcpu->arch.guest_gprs[base2];
+		useraddr += vcpu->run->s.regs.gprs[base2];
 
 	if (useraddr & 1) {
 		kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
@@ -180,7 +180,7 @@ static int handle_stidp(struct kvm_vcpu *vcpu)
 	vcpu->stat.instruction_stidp++;
 	operand2 = disp2;
 	if (base2)
-		operand2 += vcpu->arch.guest_gprs[base2];
+		operand2 += vcpu->run->s.regs.gprs[base2];
 
 	if (operand2 & 7) {
 		kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
@@ -231,9 +231,9 @@ static void handle_stsi_3_2_2(struct kvm_vcpu *vcpu, struct sysinfo_3_2_2 *mem)
 
 static int handle_stsi(struct kvm_vcpu *vcpu)
 {
-	int fc = (vcpu->arch.guest_gprs[0] & 0xf0000000) >> 28;
-	int sel1 = vcpu->arch.guest_gprs[0] & 0xff;
-	int sel2 = vcpu->arch.guest_gprs[1] & 0xffff;
+	int fc = (vcpu->run->s.regs.gprs[0] & 0xf0000000) >> 28;
+	int sel1 = vcpu->run->s.regs.gprs[0] & 0xff;
+	int sel2 = vcpu->run->s.regs.gprs[1] & 0xffff;
 	int base2 = vcpu->arch.sie_block->ipb >> 28;
 	int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
 	u64 operand2;
@@ -244,14 +244,14 @@ static int handle_stsi(struct kvm_vcpu *vcpu)
 
 	operand2 = disp2;
 	if (base2)
-		operand2 += vcpu->arch.guest_gprs[base2];
+		operand2 += vcpu->run->s.regs.gprs[base2];
 
 	if (operand2 & 0xfff && fc > 0)
 		return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
 
 	switch (fc) {
 	case 0:
-		vcpu->arch.guest_gprs[0] = 3 << 28;
+		vcpu->run->s.regs.gprs[0] = 3 << 28;
 		vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
 		return 0;
 	case 1: /* same handling for 1 and 2 */
@@ -280,7 +280,7 @@ static int handle_stsi(struct kvm_vcpu *vcpu)
 	}
 	free_page(mem);
 	vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
-	vcpu->arch.guest_gprs[0] = 0;
+	vcpu->run->s.regs.gprs[0] = 0;
 	return 0;
 out_mem:
 	free_page(mem);
@@ -332,8 +332,8 @@ static int handle_tprot(struct kvm_vcpu *vcpu)
 	int disp1 = (vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16;
 	int base2 = (vcpu->arch.sie_block->ipb & 0xf000) >> 12;
 	int disp2 = vcpu->arch.sie_block->ipb & 0x0fff;
-	u64 address1 = disp1 + base1 ? vcpu->arch.guest_gprs[base1] : 0;
-	u64 address2 = disp2 + base2 ? vcpu->arch.guest_gprs[base2] : 0;
+	u64 address1 = disp1 + base1 ? vcpu->run->s.regs.gprs[base1] : 0;
+	u64 address2 = disp2 + base2 ? vcpu->run->s.regs.gprs[base2] : 0;
 	struct vm_area_struct *vma;
 	unsigned long user_address;
 
diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c
index 0a7941d..30eb0f7 100644
--- a/arch/s390/kvm/sigp.c
+++ b/arch/s390/kvm/sigp.c
@@ -48,7 +48,7 @@
 
 
 static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
-			unsigned long *reg)
+			u64 *reg)
 {
 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 	int rc;
@@ -220,7 +220,7 @@ static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
 }
 
 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
-			     unsigned long *reg)
+			     u64 *reg)
 {
 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 	struct kvm_s390_local_interrupt *li = NULL;
@@ -278,7 +278,7 @@ out_fi:
 }
 
 static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr,
-				unsigned long *reg)
+				u64 *reg)
 {
 	int rc;
 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
@@ -316,7 +316,7 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 	int base2 = vcpu->arch.sie_block->ipb >> 28;
 	int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
 	u32 parameter;
-	u16 cpu_addr = vcpu->arch.guest_gprs[r3];
+	u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
 	u8 order_code;
 	int rc;
 
@@ -327,18 +327,18 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 
 	order_code = disp2;
 	if (base2)
-		order_code += vcpu->arch.guest_gprs[base2];
+		order_code += vcpu->run->s.regs.gprs[base2];
 
 	if (r1 % 2)
-		parameter = vcpu->arch.guest_gprs[r1];
+		parameter = vcpu->run->s.regs.gprs[r1];
 	else
-		parameter = vcpu->arch.guest_gprs[r1 + 1];
+		parameter = vcpu->run->s.regs.gprs[r1 + 1];
 
 	switch (order_code) {
 	case SIGP_SENSE:
 		vcpu->stat.instruction_sigp_sense++;
 		rc = __sigp_sense(vcpu, cpu_addr,
-				  &vcpu->arch.guest_gprs[r1]);
+				  &vcpu->run->s.regs.gprs[r1]);
 		break;
 	case SIGP_EXTERNAL_CALL:
 		vcpu->stat.instruction_sigp_external_call++;
@@ -363,12 +363,12 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 	case SIGP_SET_PREFIX:
 		vcpu->stat.instruction_sigp_prefix++;
 		rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
-				       &vcpu->arch.guest_gprs[r1]);
+				       &vcpu->run->s.regs.gprs[r1]);
 		break;
 	case SIGP_SENSE_RUNNING:
 		vcpu->stat.instruction_sigp_sense_running++;
 		rc = __sigp_sense_running(vcpu, cpu_addr,
-					  &vcpu->arch.guest_gprs[r1]);
+					  &vcpu->run->s.regs.gprs[r1]);
 		break;
 	case SIGP_RESTART:
 		vcpu->stat.instruction_sigp_restart++;
-- 
1.7.8.2

[PATCH 4/4] kvm-s390: provide access guest registers via kvm_run

[Christian Borntraeger]

This patch adds the access registers to the kvm_run structure.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 arch/s390/include/asm/kvm.h      |    2 ++
 arch/s390/include/asm/kvm_host.h |    1 -
 arch/s390/kvm/kvm-s390.c         |   16 +++++++++-------
 3 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/arch/s390/include/asm/kvm.h b/arch/s390/include/asm/kvm.h
index 420dbb7..9acbde4 100644
--- a/arch/s390/include/asm/kvm.h
+++ b/arch/s390/include/asm/kvm.h
@@ -43,9 +43,11 @@ struct kvm_guest_debug_arch {
 
 #define KVM_SYNC_PREFIX (1UL << 0)
 #define KVM_SYNC_GPRS   (1UL << 1)
+#define KVM_SYNC_ACRS   (1UL << 2)
 /* definition of registers in kvm_run */
 struct kvm_sync_regs {
 	__u64 prefix;	/* prefix register */
 	__u64 gprs[16];	/* general purpose registers */
+	__u32 acrs[16];	/* access registers */
 };
 #endif
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index ed843ca..e630426 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -231,7 +231,6 @@ struct kvm_vcpu_arch {
 	s390_fp_regs      host_fpregs;
 	unsigned int      host_acrs[NUM_ACRS];
 	s390_fp_regs      guest_fpregs;
-	unsigned int      guest_acrs[NUM_ACRS];
 	struct kvm_s390_local_interrupt local_int;
 	struct hrtimer    ckc_timer;
 	struct tasklet_struct tasklet;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 80b12ba..0b91679 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -289,7 +289,9 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
 	}
 
 	vcpu->arch.gmap = vcpu->kvm->arch.gmap;
-	vcpu->run->kvm_valid_regs = KVM_SYNC_PREFIX | KVM_SYNC_GPRS;
+	vcpu->run->kvm_valid_regs = KVM_SYNC_PREFIX |
+				    KVM_SYNC_GPRS |
+				    KVM_SYNC_ACRS;
 	return 0;
 }
 
@@ -304,7 +306,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 	save_access_regs(vcpu->arch.host_acrs);
 	vcpu->arch.guest_fpregs.fpc &= FPC_VALID_MASK;
 	restore_fp_regs(&vcpu->arch.guest_fpregs);
-	restore_access_regs(vcpu->arch.guest_acrs);
+	restore_access_regs(vcpu->run->s.regs.acrs);
 	gmap_enable(vcpu->arch.gmap);
 	atomic_set_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
 }
@@ -314,7 +316,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 	atomic_clear_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
 	gmap_disable(vcpu->arch.gmap);
 	save_fp_regs(&vcpu->arch.guest_fpregs);
-	save_access_regs(vcpu->arch.guest_acrs);
+	save_access_regs(vcpu->run->s.regs.acrs);
 	restore_fp_regs(&vcpu->arch.host_fpregs);
 	restore_access_regs(vcpu->arch.host_acrs);
 }
@@ -441,16 +443,16 @@ int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 				  struct kvm_sregs *sregs)
 {
-	memcpy(&vcpu->arch.guest_acrs, &sregs->acrs, sizeof(sregs->acrs));
+	memcpy(&vcpu->run->s.regs.acrs, &sregs->acrs, sizeof(sregs->acrs));
 	memcpy(&vcpu->arch.sie_block->gcr, &sregs->crs, sizeof(sregs->crs));
-	restore_access_regs(vcpu->arch.guest_acrs);
+	restore_access_regs(vcpu->run->s.regs.acrs);
 	return 0;
 }
 
 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 				  struct kvm_sregs *sregs)
 {
-	memcpy(&sregs->acrs, &vcpu->arch.guest_acrs, sizeof(sregs->acrs));
+	memcpy(&sregs->acrs, &vcpu->run->s.regs.acrs, sizeof(sregs->acrs));
 	memcpy(&sregs->crs, &vcpu->arch.sie_block->gcr, sizeof(sregs->crs));
 	return 0;
 }
@@ -702,7 +704,7 @@ int kvm_s390_vcpu_store_status(struct kvm_vcpu *vcpu, unsigned long addr)
 		return -EFAULT;
 
 	if (__guestcopy(vcpu, addr + offsetof(struct save_area, acc_regs),
-			&vcpu->arch.guest_acrs, 64, prefix))
+			&vcpu->run->s.regs.acrs, 64, prefix))
 		return -EFAULT;
 
 	if (__guestcopy(vcpu,
-- 
1.7.8.2

Re: kvm: provide synchronous registers in kvm_run

[Alexander Graf]

On 01/11/2012 11:20 AM, Christian Borntraeger wrote:
> Avi, Marcelo,
>
> here is the next version of the sync register patch series.

A small hint for patch sets:

$ git format-patch -n --cover-letter ...

generates a 0000/nnnn patch mail template that contains some summary 
about your set, like which files you modified. It can be very helpful to 
at first glance see obviously wrong things :).


Alex

Re: kvm: provide synchronous registers in kvm_run

[Alexander Graf]

On 01/11/2012 11:20 AM, Christian Borntraeger wrote:
> Avi, Marcelo,
>
> here is the next version of the sync register patch series.

Whole set is:

Acked-by: Alexander Graf <agraf@suse.de>

Very cool interface addition!


Alex