KVM: s390: split SIE state guest prefix field

This patch splits the SIE state guest prefix at offset 4
into a prefix bit field. Additionally it provides the
access functions:

 - kvm_s390_get_prefix()
 - kvm_s390_set_prefix()

to access the prefix per vcpu.

Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index dc182a5..a27f500 100644 (file)
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -82,7 +82,9 @@ struct sca_block {
 
 struct kvm_s390_sie_block {
        atomic_t cpuflags;              /* 0x0000 */
-       __u32   prefix;                 /* 0x0004 */
+       __u32 : 1;                      /* 0x0004 */
+       __u32 prefix : 18;
+       __u32 : 13;
        __u8    reserved08[4];          /* 0x0008 */
 #define PROG_IN_SIE (1<<0)
        __u32   prog0c;                 /* 0x000c */

diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c
index 004d385..0161675 100644 (file)
--- a/arch/s390/kvm/diag.c
+++ b/arch/s390/kvm/diag.c
@@ -23,7 +23,7 @@
 static int diag_release_pages(struct kvm_vcpu *vcpu)
 {
        unsigned long start, end;
-       unsigned long prefix  = vcpu->arch.sie_block->prefix;
+       unsigned long prefix  = kvm_s390_get_prefix(vcpu);
 
        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;

diff --git a/arch/s390/kvm/gaccess.h b/arch/s390/kvm/gaccess.h
index 68db43e..a07ee08 100644 (file)
--- a/arch/s390/kvm/gaccess.h
+++ b/arch/s390/kvm/gaccess.h
@@ -30,7 +30,7 @@
 static inline unsigned long kvm_s390_real_to_abs(struct kvm_vcpu *vcpu,
                                                 unsigned long gra)
 {
-       unsigned long prefix = vcpu->arch.sie_block->prefix;
+       unsigned long prefix  = kvm_s390_get_prefix(vcpu);
 
        if (gra < 2 * PAGE_SIZE)
                gra += prefix;
@@ -99,7 +99,7 @@ static inline unsigned long kvm_s390_logical_to_effective(struct kvm_vcpu *vcpu,
        unsigned long __gpa;                                    \
                                                                \
        __gpa = (unsigned long)(gra);                           \
-       __gpa += __vcpu->arch.sie_block->prefix;                \
+       __gpa += kvm_s390_get_prefix(__vcpu);                   \
        kvm_write_guest(__vcpu->kvm, __gpa, &__x, sizeof(__x)); \
 })
 
@@ -124,7 +124,7 @@ static inline __must_check
 int write_guest_lc(struct kvm_vcpu *vcpu, unsigned long gra, void *data,
                   unsigned long len)
 {
-       unsigned long gpa = gra + vcpu->arch.sie_block->prefix;
+       unsigned long gpa = gra + kvm_s390_get_prefix(vcpu);
 
        return kvm_write_guest(vcpu->kvm, gpa, data, len);
 }
@@ -150,7 +150,7 @@ static inline __must_check
 int read_guest_lc(struct kvm_vcpu *vcpu, unsigned long gra, void *data,
                  unsigned long len)
 {
-       unsigned long gpa = gra + vcpu->arch.sie_block->prefix;
+       unsigned long gpa = gra + kvm_s390_get_prefix(vcpu);
 
        return kvm_read_guest(vcpu->kvm, gpa, data, len);
 }

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 2c24312..e519860 100644 (file)
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -753,7 +753,7 @@ static void kvm_gmap_notifier(struct gmap *gmap, unsigned long address)
 
        kvm_for_each_vcpu(i, vcpu, kvm) {
                /* match against both prefix pages */
-               if (vcpu->arch.sie_block->prefix == (address & ~0x1000UL)) {
+               if (kvm_s390_get_prefix(vcpu) == (address & ~0x1000UL)) {
                        VCPU_EVENT(vcpu, 2, "gmap notifier for %lx", address);
                        kvm_make_request(KVM_REQ_MMU_RELOAD, vcpu);
                        exit_sie_sync(vcpu);
@@ -1017,7 +1017,7 @@ retry:
        if (kvm_check_request(KVM_REQ_MMU_RELOAD, vcpu)) {
                int rc;
                rc = gmap_ipte_notify(vcpu->arch.gmap,
-                                     vcpu->arch.sie_block->prefix,
+                                     kvm_s390_get_prefix(vcpu),
                                      PAGE_SIZE * 2);
                if (rc)
                        return rc;
@@ -1338,7 +1338,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 
        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;
+       kvm_run->s.regs.prefix = kvm_s390_get_prefix(vcpu);
        memcpy(&kvm_run->s.regs.crs, &vcpu->arch.sie_block->gcr, 128);
 
        if (vcpu->sigset_active)
@@ -1357,6 +1357,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 int kvm_s390_store_status_unloaded(struct kvm_vcpu *vcpu, unsigned long gpa)
 {
        unsigned char archmode = 1;
+       unsigned int px;
        u64 clkcomp;
        int rc;
 
@@ -1375,8 +1376,9 @@ int kvm_s390_store_status_unloaded(struct kvm_vcpu *vcpu, unsigned long gpa)
                              vcpu->run->s.regs.gprs, 128);
        rc |= write_guest_abs(vcpu, gpa + offsetof(struct save_area, psw),
                              &vcpu->arch.sie_block->gpsw, 16);
+       px = kvm_s390_get_prefix(vcpu);
        rc |= write_guest_abs(vcpu, gpa + offsetof(struct save_area, pref_reg),
-                             &vcpu->arch.sie_block->prefix, 4);
+                             &px, 4);
        rc |= write_guest_abs(vcpu,
                              gpa + offsetof(struct save_area, fp_ctrl_reg),
                              &vcpu->arch.guest_fpregs.fpc, 4);

diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index 87edfc9..a8655ed 100644 (file)
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -61,9 +61,15 @@ static inline int kvm_is_ucontrol(struct kvm *kvm)
 #endif
 }
 
+#define GUEST_PREFIX_SHIFT 13
+static inline u32 kvm_s390_get_prefix(struct kvm_vcpu *vcpu)
+{
+       return vcpu->arch.sie_block->prefix << GUEST_PREFIX_SHIFT;
+}
+
 static inline void kvm_s390_set_prefix(struct kvm_vcpu *vcpu, u32 prefix)
 {
-       vcpu->arch.sie_block->prefix = prefix & 0x7fffe000u;
+       vcpu->arch.sie_block->prefix = prefix >> GUEST_PREFIX_SHIFT;
        vcpu->arch.sie_block->ihcpu  = 0xffff;
        kvm_make_request(KVM_REQ_MMU_RELOAD, vcpu);
 }

diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
index d99f5f0..6296159 100644 (file)
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -119,8 +119,7 @@ static int handle_store_prefix(struct kvm_vcpu *vcpu)
        if (operand2 & 3)
                return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
 
-       address = vcpu->arch.sie_block->prefix;
-       address = address & 0x7fffe000u;
+       address = kvm_s390_get_prefix(vcpu);
 
        /* get the value */
        rc = write_guest(vcpu, operand2, &address, sizeof(address));