Add a guest_memfd file descriptor and offset to kvm__register_mem(). When guest_memfd >= 0, set KVM_MEM_GUEST_MEMFD and populate the guest_memfd fields, binding the memslot to the file. This prepares for backing guest RAM with guest_memfd on arm64. Signed-off-by: Fuad Tabba --- hw/cfi_flash.c | 2 +- include/kvm/kvm.h | 15 +++++++++++++-- kvm.c | 9 ++++++++- 3 files changed, 22 insertions(+), 4 deletions(-) diff --git a/hw/cfi_flash.c b/hw/cfi_flash.c index b68d9e0..4413955 100644 --- a/hw/cfi_flash.c +++ b/hw/cfi_flash.c @@ -451,7 +451,7 @@ static int map_flash_memory(struct kvm *kvm, struct cfi_flash_device *sfdev) int ret; ret = kvm__register_mem(kvm, sfdev->base_addr, sfdev->size, - sfdev->flash_memory, + sfdev->flash_memory, -1, 0, KVM_MEM_TYPE_RAM | KVM_MEM_TYPE_READONLY); if (!ret) sfdev->is_mapped = true; diff --git a/include/kvm/kvm.h b/include/kvm/kvm.h index eb23e2f..5e7b5eb 100644 --- a/include/kvm/kvm.h +++ b/include/kvm/kvm.h @@ -128,11 +128,22 @@ bool kvm__emulate_io(struct kvm_cpu *vcpu, u16 port, void *data, int direction, bool kvm__emulate_mmio(struct kvm_cpu *vcpu, u64 phys_addr, u8 *data, u32 len, u8 is_write); int kvm__destroy_mem(struct kvm *kvm, u64 guest_phys, u64 size, void *userspace_addr); int kvm__register_mem(struct kvm *kvm, u64 guest_phys, u64 size, void *userspace_addr, + int guest_memfd, u64 guest_memfd_offset, enum kvm_mem_type type); static inline int kvm__register_ram(struct kvm *kvm, u64 guest_phys, u64 size, void *userspace_addr) { return kvm__register_mem(kvm, guest_phys, size, userspace_addr, + -1, 0, KVM_MEM_TYPE_RAM); +} + +static inline int kvm__register_ram_guest_memfd(struct kvm *kvm, u64 guest_phys, + u64 size, void *userspace_addr, + int guest_memfd, + u64 guest_memfd_offset) +{ + return kvm__register_mem(kvm, guest_phys, size, userspace_addr, + guest_memfd, guest_memfd_offset, KVM_MEM_TYPE_RAM); } @@ -140,13 +151,13 @@ static inline int kvm__register_dev_mem(struct kvm *kvm, u64 guest_phys, u64 size, void *userspace_addr) { return kvm__register_mem(kvm, guest_phys, size, userspace_addr, - KVM_MEM_TYPE_DEVICE); + -1, 0, KVM_MEM_TYPE_DEVICE); } static inline int kvm__reserve_mem(struct kvm *kvm, u64 guest_phys, u64 size) { return kvm__register_mem(kvm, guest_phys, size, NULL, - KVM_MEM_TYPE_RESERVED); + -1, 0, KVM_MEM_TYPE_RESERVED); } int __must_check kvm__register_iotrap(struct kvm *kvm, u64 phys_addr, u64 len, diff --git a/kvm.c b/kvm.c index 8a7fd09..3d05756 100644 --- a/kvm.c +++ b/kvm.c @@ -237,7 +237,8 @@ out: } int kvm__register_mem(struct kvm *kvm, u64 guest_phys, u64 size, - void *userspace_addr, enum kvm_mem_type type) + void *userspace_addr, int guest_memfd, + u64 guest_memfd_offset, enum kvm_mem_type type) { struct kvm_mem_bank *merged = NULL; struct kvm_mem_bank *bank; @@ -327,6 +328,12 @@ int kvm__register_mem(struct kvm *kvm, u64 guest_phys, u64 size, .userspace_addr = (unsigned long)userspace_addr, }; + if (guest_memfd >= 0) { + mem.flags |= KVM_MEM_GUEST_MEMFD; + mem.guest_memfd = guest_memfd; + mem.guest_memfd_offset = guest_memfd_offset; + } + ret = ioctl(kvm->vm_fd, KVM_SET_USER_MEMORY_REGION2, &mem); if (ret < 0) { ret = -errno; -- 2.39.5