diff options
| -rw-r--r-- | arch/x86/kvm/x86.c | 1 | ||||
| -rw-r--r-- | include/uapi/linux/kvm.h | 3 | ||||
| -rw-r--r-- | virt/kvm/eventfd.c | 27 |
3 files changed, 25 insertions, 6 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 8b8fc0b792ba..bc4aaf68190c 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2644,6 +2644,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_IRQ_INJECT_STATUS: case KVM_CAP_IRQFD: case KVM_CAP_IOEVENTFD: + case KVM_CAP_IOEVENTFD_NO_LENGTH: case KVM_CAP_PIT2: case KVM_CAP_PIT_STATE2: case KVM_CAP_SET_IDENTITY_MAP_ADDR: diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index a8f4ee5d2e82..39098a61f41c 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -529,7 +529,7 @@ enum { struct kvm_ioeventfd { __u64 datamatch; __u64 addr; /* legal pio/mmio address */ - __u32 len; /* 1, 2, 4, or 8 bytes */ + __u32 len; /* 1, 2, 4, or 8 bytes; or 0 to ignore length */ __s32 fd; __u32 flags; __u8 pad[36]; @@ -743,6 +743,7 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_IOAPIC_POLARITY_IGNORED 97 #define KVM_CAP_ENABLE_CAP_VM 98 #define KVM_CAP_S390_IRQCHIP 99 +#define KVM_CAP_IOEVENTFD_NO_LENGTH 100 #ifdef KVM_CAP_IRQ_ROUTING diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c index 29c2a04e036e..2721996bb9c2 100644 --- a/virt/kvm/eventfd.c +++ b/virt/kvm/eventfd.c @@ -600,7 +600,15 @@ ioeventfd_in_range(struct _ioeventfd *p, gpa_t addr, int len, const void *val) { u64 _val; - if (!(addr == p->addr && len == p->length)) + if (addr != p->addr) + /* address must be precise for a hit */ + return false; + + if (!p->length) + /* length = 0 means only look at the address, so always a hit */ + return true; + + if (len != p->length) /* address-range must be precise for a hit */ return false; @@ -671,9 +679,11 @@ ioeventfd_check_collision(struct kvm *kvm, struct _ioeventfd *p) list_for_each_entry(_p, &kvm->ioeventfds, list) if (_p->bus_idx == p->bus_idx && - _p->addr == p->addr && _p->length == p->length && - (_p->wildcard || p->wildcard || - _p->datamatch == p->datamatch)) + _p->addr == p->addr && + (!_p->length || !p->length || + (_p->length == p->length && + (_p->wildcard || p->wildcard || + _p->datamatch == p->datamatch)))) return true; return false; @@ -697,8 +707,9 @@ kvm_assign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args) int ret; bus_idx = ioeventfd_bus_from_flags(args->flags); - /* must be natural-word sized */ + /* must be natural-word sized, or 0 to ignore length */ switch (args->len) { + case 0: case 1: case 2: case 4: @@ -716,6 +727,12 @@ kvm_assign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args) if (args->flags & ~KVM_IOEVENTFD_VALID_FLAG_MASK) return -EINVAL; + /* ioeventfd with no length can't be combined with DATAMATCH */ + if (!args->len && + args->flags & (KVM_IOEVENTFD_FLAG_PIO | + KVM_IOEVENTFD_FLAG_DATAMATCH)) + return -EINVAL; + eventfd = eventfd_ctx_fdget(args->fd); if (IS_ERR(eventfd)) return PTR_ERR(eventfd); |