diff options
Diffstat (limited to 'arch/s390/kvm/diag.c')
| -rw-r--r-- | arch/s390/kvm/diag.c | 26 |
1 files changed, 18 insertions, 8 deletions
diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c index b374b6cb7785..9254afff250c 100644 --- a/arch/s390/kvm/diag.c +++ b/arch/s390/kvm/diag.c @@ -28,22 +28,32 @@ static int diag_release_pages(struct kvm_vcpu *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; - if (start & ~PAGE_MASK || end & ~PAGE_MASK || start > end + if (start & ~PAGE_MASK || end & ~PAGE_MASK || start >= end || start < 2 * PAGE_SIZE) return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION); VCPU_EVENT(vcpu, 5, "diag release pages %lX %lX", start, end); vcpu->stat.diagnose_10++; - /* we checked for start > end above */ - if (end < prefix || start >= prefix + 2 * PAGE_SIZE) { + /* + * We checked for start >= end above, so lets check for the + * fast path (no prefix swap page involved) + */ + if (end <= prefix || start >= prefix + 2 * PAGE_SIZE) { gmap_discard(vcpu->arch.gmap, start, end); } else { - if (start < prefix) - gmap_discard(vcpu->arch.gmap, start, prefix); - if (end >= prefix) - gmap_discard(vcpu->arch.gmap, - prefix + 2 * PAGE_SIZE, end); + /* + * This is slow path. gmap_discard will check for start + * so lets split this into before prefix, prefix, after + * prefix and let gmap_discard make some of these calls + * NOPs. + */ + gmap_discard(vcpu->arch.gmap, start, prefix); + if (start <= prefix) + gmap_discard(vcpu->arch.gmap, 0, 4096); + if (end > prefix + 4096) + gmap_discard(vcpu->arch.gmap, 4096, 8192); + gmap_discard(vcpu->arch.gmap, prefix + 2 * PAGE_SIZE, end); } return 0; } |