diff options
Diffstat (limited to 'arch/s390/kvm/gaccess.h')
-rw-r--r-- | arch/s390/kvm/gaccess.h | 243 |
1 files changed, 175 insertions, 68 deletions
diff --git a/arch/s390/kvm/gaccess.h b/arch/s390/kvm/gaccess.h index 03c716a0f01f..c86f6ae43f76 100644 --- a/arch/s390/kvm/gaccess.h +++ b/arch/s390/kvm/gaccess.h @@ -1,5 +1,5 @@ /* - * gaccess.h - access guest memory + * access.h - access guest memory * * Copyright IBM Corp. 2008,2009 * @@ -22,20 +22,13 @@ static inline void __user *__guestaddr_to_user(struct kvm_vcpu *vcpu, unsigned long guestaddr) { unsigned long prefix = vcpu->arch.sie_block->prefix; - unsigned long origin = vcpu->arch.sie_block->gmsor; - unsigned long memsize = kvm_s390_vcpu_get_memsize(vcpu); if (guestaddr < 2 * PAGE_SIZE) guestaddr += prefix; else if ((guestaddr >= prefix) && (guestaddr < prefix + 2 * PAGE_SIZE)) guestaddr -= prefix; - if (guestaddr > memsize) - return (void __user __force *) ERR_PTR(-EFAULT); - - guestaddr += origin; - - return (void __user *) guestaddr; + return (void __user *) gmap_fault(guestaddr, vcpu->arch.gmap); } static inline int get_guest_u64(struct kvm_vcpu *vcpu, unsigned long guestaddr, @@ -141,11 +134,11 @@ static inline int put_guest_u8(struct kvm_vcpu *vcpu, unsigned long guestaddr, static inline int __copy_to_guest_slow(struct kvm_vcpu *vcpu, unsigned long guestdest, - const void *from, unsigned long n) + void *from, unsigned long n) { int rc; unsigned long i; - const u8 *data = from; + u8 *data = from; for (i = 0; i < n; i++) { rc = put_guest_u8(vcpu, guestdest++, *(data++)); @@ -155,12 +148,95 @@ static inline int __copy_to_guest_slow(struct kvm_vcpu *vcpu, 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, - const void *from, unsigned long n) + void *from, unsigned long n) { unsigned long prefix = vcpu->arch.sie_block->prefix; - unsigned long origin = vcpu->arch.sie_block->gmsor; - unsigned long memsize = kvm_s390_vcpu_get_memsize(vcpu); if ((guestdest < 2 * PAGE_SIZE) && (guestdest + n > 2 * PAGE_SIZE)) goto slowpath; @@ -177,15 +253,7 @@ static inline int copy_to_guest(struct kvm_vcpu *vcpu, unsigned long guestdest, else if ((guestdest >= prefix) && (guestdest < prefix + 2 * PAGE_SIZE)) guestdest -= prefix; - if (guestdest + n > memsize) - return -EFAULT; - - if (guestdest + n < guestdest) - return -EFAULT; - - guestdest += origin; - - return copy_to_user((void __user *) guestdest, from, n); + return __copy_to_guest_fast(vcpu, guestdest, from, n); slowpath: return __copy_to_guest_slow(vcpu, guestdest, from, n); } @@ -206,74 +274,113 @@ static inline int __copy_from_guest_slow(struct kvm_vcpu *vcpu, void *to, return 0; } -static inline int copy_from_guest(struct kvm_vcpu *vcpu, void *to, - unsigned long guestsrc, unsigned long n) +static inline int __copy_from_guest_fast(struct kvm_vcpu *vcpu, void *to, + unsigned long guestsrc, + unsigned long n) { - unsigned long prefix = vcpu->arch.sie_block->prefix; - unsigned long origin = vcpu->arch.sie_block->gmsor; - unsigned long memsize = kvm_s390_vcpu_get_memsize(vcpu); + int r; + void __user *uptr; + unsigned long size; - if ((guestsrc < 2 * PAGE_SIZE) && (guestsrc + n > 2 * PAGE_SIZE)) - goto slowpath; + if (guestsrc + n < guestsrc) + return -EFAULT; - if ((guestsrc < prefix) && (guestsrc + n > prefix)) - goto slowpath; + /* 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 ((guestsrc < prefix + 2 * PAGE_SIZE) - && (guestsrc + n > prefix + 2 * PAGE_SIZE)) - goto slowpath; + if (IS_ERR((void __force *) uptr)) + return PTR_ERR((void __force *) uptr); - if (guestsrc < 2 * PAGE_SIZE) - guestsrc += prefix; - else if ((guestsrc >= prefix) && (guestsrc < prefix + 2 * PAGE_SIZE)) - guestsrc -= prefix; + r = copy_from_user(to, uptr, n); - if (guestsrc + n > memsize) - return -EFAULT; + if (r) + r = -EFAULT; - if (guestsrc + n < guestsrc) - return -EFAULT; + goto out; + } - guestsrc += origin; + /* copy first segment */ + uptr = (void __user *)gmap_fault(guestsrc, vcpu->arch.gmap); - return copy_from_user(to, (void __user *) guestsrc, n); -slowpath: - return __copy_from_guest_slow(vcpu, to, guestsrc, n); -} + if (IS_ERR((void __force *) uptr)) + return PTR_ERR((void __force *) uptr); -static inline int copy_to_guest_absolute(struct kvm_vcpu *vcpu, - unsigned long guestdest, - const void *from, unsigned long n) -{ - unsigned long origin = vcpu->arch.sie_block->gmsor; - unsigned long memsize = kvm_s390_vcpu_get_memsize(vcpu); + size = PMD_SIZE - (guestsrc & ~PMD_MASK); - if (guestdest + n > memsize) - return -EFAULT; + r = copy_from_user(to, uptr, size); - if (guestdest + n < guestdest) - return -EFAULT; + 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); - guestdest += origin; + if (IS_ERR((void __force *) uptr)) + return PTR_ERR((void __force *) uptr); - return copy_to_user((void __user *) guestdest, from, n); + 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) { - unsigned long origin = vcpu->arch.sie_block->gmsor; - unsigned long memsize = kvm_s390_vcpu_get_memsize(vcpu); + return __copy_from_guest_fast(vcpu, to, guestsrc, n); +} - if (guestsrc + n > memsize) - return -EFAULT; +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 + n < guestsrc) - return -EFAULT; + if ((guestsrc < 2 * PAGE_SIZE) && (guestsrc + n > 2 * PAGE_SIZE)) + goto slowpath; - guestsrc += origin; + 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_user(to, (void __user *) guestsrc, n); + return __copy_from_guest_fast(vcpu, to, guestsrc, n); +slowpath: + return __copy_from_guest_slow(vcpu, to, guestsrc, n); } #endif |