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-rw-r--r--arch/s390/kvm/gaccess.h386
1 files changed, 386 insertions, 0 deletions
diff --git a/arch/s390/kvm/gaccess.h b/arch/s390/kvm/gaccess.h
new file mode 100644
index 00000000..c86f6ae4
--- /dev/null
+++ b/arch/s390/kvm/gaccess.h
@@ -0,0 +1,386 @@
+/*
+ * access.h - access guest memory
+ *
+ * Copyright IBM Corp. 2008,2009
+ *
+ * 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): Carsten Otte <cotte@de.ibm.com>
+ */
+
+#ifndef __KVM_S390_GACCESS_H
+#define __KVM_S390_GACCESS_H
+
+#include <linux/compiler.h>
+#include <linux/kvm_host.h>
+#include <asm/uaccess.h>
+#include "kvm-s390.h"
+
+static inline void __user *__guestaddr_to_user(struct kvm_vcpu *vcpu,
+ unsigned long guestaddr)
+{
+ unsigned long prefix = vcpu->arch.sie_block->prefix;
+
+ if (guestaddr < 2 * PAGE_SIZE)
+ guestaddr += prefix;
+ else if ((guestaddr >= prefix) && (guestaddr < prefix + 2 * PAGE_SIZE))
+ guestaddr -= prefix;
+
+ return (void __user *) gmap_fault(guestaddr, vcpu->arch.gmap);
+}
+
+static inline int get_guest_u64(struct kvm_vcpu *vcpu, unsigned long guestaddr,
+ u64 *result)
+{
+ void __user *uptr = __guestaddr_to_user(vcpu, guestaddr);
+
+ BUG_ON(guestaddr & 7);
+
+ if (IS_ERR((void __force *) uptr))
+ return PTR_ERR((void __force *) uptr);
+
+ return get_user(*result, (unsigned long __user *) uptr);
+}
+
+static inline int get_guest_u32(struct kvm_vcpu *vcpu, unsigned long guestaddr,
+ u32 *result)
+{
+ void __user *uptr = __guestaddr_to_user(vcpu, guestaddr);
+
+ BUG_ON(guestaddr & 3);
+
+ if (IS_ERR((void __force *) uptr))
+ return PTR_ERR((void __force *) uptr);
+
+ return get_user(*result, (u32 __user *) uptr);
+}
+
+static inline int get_guest_u16(struct kvm_vcpu *vcpu, unsigned long guestaddr,
+ u16 *result)
+{
+ void __user *uptr = __guestaddr_to_user(vcpu, guestaddr);
+
+ BUG_ON(guestaddr & 1);
+
+ if (IS_ERR(uptr))
+ return PTR_ERR(uptr);
+
+ return get_user(*result, (u16 __user *) uptr);
+}
+
+static inline int get_guest_u8(struct kvm_vcpu *vcpu, unsigned long guestaddr,
+ u8 *result)
+{
+ void __user *uptr = __guestaddr_to_user(vcpu, guestaddr);
+
+ if (IS_ERR((void __force *) uptr))
+ return PTR_ERR((void __force *) uptr);
+
+ return get_user(*result, (u8 __user *) uptr);
+}
+
+static inline int put_guest_u64(struct kvm_vcpu *vcpu, unsigned long guestaddr,
+ u64 value)
+{
+ void __user *uptr = __guestaddr_to_user(vcpu, guestaddr);
+
+ BUG_ON(guestaddr & 7);
+
+ if (IS_ERR((void __force *) uptr))
+ return PTR_ERR((void __force *) uptr);
+
+ return put_user(value, (u64 __user *) uptr);
+}
+
+static inline int put_guest_u32(struct kvm_vcpu *vcpu, unsigned long guestaddr,
+ u32 value)
+{
+ void __user *uptr = __guestaddr_to_user(vcpu, guestaddr);
+
+ BUG_ON(guestaddr & 3);
+
+ if (IS_ERR((void __force *) uptr))
+ return PTR_ERR((void __force *) uptr);
+
+ return put_user(value, (u32 __user *) uptr);
+}
+
+static inline int put_guest_u16(struct kvm_vcpu *vcpu, unsigned long guestaddr,
+ u16 value)
+{
+ void __user *uptr = __guestaddr_to_user(vcpu, guestaddr);
+
+ BUG_ON(guestaddr & 1);
+
+ if (IS_ERR((void __force *) uptr))
+ return PTR_ERR((void __force *) uptr);
+
+ return put_user(value, (u16 __user *) uptr);
+}
+
+static inline int put_guest_u8(struct kvm_vcpu *vcpu, unsigned long guestaddr,
+ u8 value)
+{
+ void __user *uptr = __guestaddr_to_user(vcpu, guestaddr);
+
+ if (IS_ERR((void __force *) uptr))
+ return PTR_ERR((void __force *) uptr);
+
+ return put_user(value, (u8 __user *) uptr);
+}
+
+
+static inline int __copy_to_guest_slow(struct kvm_vcpu *vcpu,
+ unsigned long guestdest,
+ void *from, unsigned long n)
+{
+ int rc;
+ unsigned long i;
+ u8 *data = from;
+
+ for (i = 0; i < n; i++) {
+ rc = put_guest_u8(vcpu, guestdest++, *(data++));
+ if (rc < 0)
+ return rc;
+ }
+ return 0;
+}
+
+static inline int __copy_to_guest_fast(struct kvm_vcpu *vcpu,
+ unsigned long guestdest,
+ void *from, unsigned long n)
+{
+ int r;
+ void __user *uptr;
+ unsigned long size;
+
+ if (guestdest + n < guestdest)
+ return -EFAULT;
+
+ /* simple case: all within one segment table entry? */
+ if ((guestdest & PMD_MASK) == ((guestdest+n) & PMD_MASK)) {
+ uptr = (void __user *) gmap_fault(guestdest, vcpu->arch.gmap);
+
+ if (IS_ERR((void __force *) uptr))
+ return PTR_ERR((void __force *) uptr);
+
+ r = copy_to_user(uptr, from, n);
+
+ if (r)
+ r = -EFAULT;
+
+ goto out;
+ }
+
+ /* copy first segment */
+ uptr = (void __user *)gmap_fault(guestdest, vcpu->arch.gmap);
+
+ if (IS_ERR((void __force *) uptr))
+ return PTR_ERR((void __force *) uptr);
+
+ size = PMD_SIZE - (guestdest & ~PMD_MASK);
+
+ r = copy_to_user(uptr, from, size);
+
+ if (r) {
+ r = -EFAULT;
+ goto out;
+ }
+ from += size;
+ n -= size;
+ guestdest += size;
+
+ /* copy full segments */
+ while (n >= PMD_SIZE) {
+ uptr = (void __user *)gmap_fault(guestdest, vcpu->arch.gmap);
+
+ if (IS_ERR((void __force *) uptr))
+ return PTR_ERR((void __force *) uptr);
+
+ r = copy_to_user(uptr, from, PMD_SIZE);
+
+ if (r) {
+ r = -EFAULT;
+ goto out;
+ }
+ from += PMD_SIZE;
+ n -= PMD_SIZE;
+ guestdest += PMD_SIZE;
+ }
+
+ /* copy the tail segment */
+ if (n) {
+ uptr = (void __user *)gmap_fault(guestdest, vcpu->arch.gmap);
+
+ if (IS_ERR((void __force *) uptr))
+ return PTR_ERR((void __force *) uptr);
+
+ r = copy_to_user(uptr, from, n);
+
+ if (r)
+ r = -EFAULT;
+ }
+out:
+ return r;
+}
+
+static inline int copy_to_guest_absolute(struct kvm_vcpu *vcpu,
+ unsigned long guestdest,
+ void *from, unsigned long n)
+{
+ return __copy_to_guest_fast(vcpu, guestdest, from, n);
+}
+
+static inline int copy_to_guest(struct kvm_vcpu *vcpu, unsigned long guestdest,
+ void *from, unsigned long n)
+{
+ unsigned long prefix = vcpu->arch.sie_block->prefix;
+
+ if ((guestdest < 2 * PAGE_SIZE) && (guestdest + n > 2 * PAGE_SIZE))
+ goto slowpath;
+
+ if ((guestdest < prefix) && (guestdest + n > prefix))
+ goto slowpath;
+
+ if ((guestdest < prefix + 2 * PAGE_SIZE)
+ && (guestdest + n > prefix + 2 * PAGE_SIZE))
+ goto slowpath;
+
+ if (guestdest < 2 * PAGE_SIZE)
+ guestdest += prefix;
+ else if ((guestdest >= prefix) && (guestdest < prefix + 2 * PAGE_SIZE))
+ guestdest -= prefix;
+
+ return __copy_to_guest_fast(vcpu, guestdest, from, n);
+slowpath:
+ return __copy_to_guest_slow(vcpu, guestdest, from, n);
+}
+
+static inline int __copy_from_guest_slow(struct kvm_vcpu *vcpu, void *to,
+ unsigned long guestsrc,
+ unsigned long n)
+{
+ int rc;
+ unsigned long i;
+ u8 *data = to;
+
+ for (i = 0; i < n; i++) {
+ rc = get_guest_u8(vcpu, guestsrc++, data++);
+ if (rc < 0)
+ return rc;
+ }
+ return 0;
+}
+
+static inline int __copy_from_guest_fast(struct kvm_vcpu *vcpu, void *to,
+ unsigned long guestsrc,
+ unsigned long n)
+{
+ int r;
+ void __user *uptr;
+ unsigned long size;
+
+ if (guestsrc + n < guestsrc)
+ return -EFAULT;
+
+ /* simple case: all within one segment table entry? */
+ if ((guestsrc & PMD_MASK) == ((guestsrc+n) & PMD_MASK)) {
+ uptr = (void __user *) gmap_fault(guestsrc, vcpu->arch.gmap);
+
+ if (IS_ERR((void __force *) uptr))
+ return PTR_ERR((void __force *) uptr);
+
+ r = copy_from_user(to, uptr, n);
+
+ if (r)
+ r = -EFAULT;
+
+ goto out;
+ }
+
+ /* copy first segment */
+ uptr = (void __user *)gmap_fault(guestsrc, vcpu->arch.gmap);
+
+ if (IS_ERR((void __force *) uptr))
+ return PTR_ERR((void __force *) uptr);
+
+ size = PMD_SIZE - (guestsrc & ~PMD_MASK);
+
+ r = copy_from_user(to, uptr, size);
+
+ if (r) {
+ r = -EFAULT;
+ goto out;
+ }
+ to += size;
+ n -= size;
+ guestsrc += size;
+
+ /* copy full segments */
+ while (n >= PMD_SIZE) {
+ uptr = (void __user *)gmap_fault(guestsrc, vcpu->arch.gmap);
+
+ if (IS_ERR((void __force *) uptr))
+ return PTR_ERR((void __force *) uptr);
+
+ r = copy_from_user(to, uptr, PMD_SIZE);
+
+ if (r) {
+ r = -EFAULT;
+ goto out;
+ }
+ to += PMD_SIZE;
+ n -= PMD_SIZE;
+ guestsrc += PMD_SIZE;
+ }
+
+ /* copy the tail segment */
+ if (n) {
+ uptr = (void __user *)gmap_fault(guestsrc, vcpu->arch.gmap);
+
+ if (IS_ERR((void __force *) uptr))
+ return PTR_ERR((void __force *) uptr);
+
+ r = copy_from_user(to, uptr, n);
+
+ if (r)
+ r = -EFAULT;
+ }
+out:
+ return r;
+}
+
+static inline int copy_from_guest_absolute(struct kvm_vcpu *vcpu, void *to,
+ unsigned long guestsrc,
+ unsigned long n)
+{
+ return __copy_from_guest_fast(vcpu, to, guestsrc, n);
+}
+
+static inline int copy_from_guest(struct kvm_vcpu *vcpu, void *to,
+ unsigned long guestsrc, unsigned long n)
+{
+ unsigned long prefix = vcpu->arch.sie_block->prefix;
+
+ if ((guestsrc < 2 * PAGE_SIZE) && (guestsrc + n > 2 * PAGE_SIZE))
+ goto slowpath;
+
+ if ((guestsrc < prefix) && (guestsrc + n > prefix))
+ goto slowpath;
+
+ if ((guestsrc < prefix + 2 * PAGE_SIZE)
+ && (guestsrc + n > prefix + 2 * PAGE_SIZE))
+ goto slowpath;
+
+ if (guestsrc < 2 * PAGE_SIZE)
+ guestsrc += prefix;
+ else if ((guestsrc >= prefix) && (guestsrc < prefix + 2 * PAGE_SIZE))
+ guestsrc -= prefix;
+
+ return __copy_from_guest_fast(vcpu, to, guestsrc, n);
+slowpath:
+ return __copy_from_guest_slow(vcpu, to, guestsrc, n);
+}
+#endif
generated by cgit (git 2.34.1) at 2025-01-10 22:16:02 +0000