[RFC PATCH v1 31/37] KVM: selftests: Provide common function to set memory attributes
From: Ackerley Tng <hidden>
Date: 2025-10-17 20:13:24
Also in:
cgroups, kvm, linux-doc, linux-fsdevel, linux-kselftest, linux-mm, lkml
Subsystem:
kernel selftest framework, kernel virtual machine (kvm), the rest · Maintainers:
Shuah Khan, Shuah Khan, Paolo Bonzini, Linus Torvalds
From: Sean Christopherson <seanjc@google.com>
Introduce vm_mem_set_memory_attributes(), which handles setting of memory
attributes for a range of guest physical addresses, regardless of whether
the attributes should be set via guest_memfd or via the memory attributes
at the VM level.
Refactor existing vm_mem_set_{shared,private} functions to use the new
function.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Co-developed-by: Ackerley Tng <redacted>
Signed-off-by: Ackerley Tng <redacted>
---
.../testing/selftests/kvm/include/kvm_util.h | 44 ++++++++++++++-----
1 file changed, 32 insertions(+), 12 deletions(-)
diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index e9c2696770cf0..9f5338bd82b24 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h@@ -435,18 +435,6 @@ static inline void vm_set_memory_attributes(struct kvm_vm *vm, uint64_t gpa, vm_ioctl(vm, KVM_SET_MEMORY_ATTRIBUTES2, &attr); } -static inline void vm_mem_set_private(struct kvm_vm *vm, uint64_t gpa, - uint64_t size) -{ - vm_set_memory_attributes(vm, gpa, size, KVM_MEMORY_ATTRIBUTE_PRIVATE); -} - -static inline void vm_mem_set_shared(struct kvm_vm *vm, uint64_t gpa, - uint64_t size) -{ - vm_set_memory_attributes(vm, gpa, size, 0); -} - static inline int __gmem_set_memory_attributes(int fd, loff_t offset, uint64_t size, uint64_t attributes,
@@ -507,6 +495,38 @@ static inline void gmem_set_shared(int fd, loff_t offset, uint64_t size) gmem_set_memory_attributes(fd, offset, size, 0); } +static inline void vm_mem_set_memory_attributes(struct kvm_vm *vm, uint64_t gpa, + uint64_t size, uint64_t attrs) +{ + if (kvm_has_gmem_attributes) { + uint64_t end = gpa + size; + uint64_t addr, len; + off_t fd_offset; + int fd; + + for (addr = gpa; addr < end; addr += len) { + fd = kvm_gpa_to_guest_memfd(vm, gpa, &fd_offset, &len); + len = min(end - addr, len); + + gmem_set_memory_attributes(fd, fd_offset, len, attrs); + } + } else { + vm_set_memory_attributes(vm, gpa, size, attrs); + } +} + +static inline void vm_mem_set_private(struct kvm_vm *vm, uint64_t gpa, + uint64_t size) +{ + vm_mem_set_memory_attributes(vm, gpa, size, KVM_MEMORY_ATTRIBUTE_PRIVATE); +} + +static inline void vm_mem_set_shared(struct kvm_vm *vm, uint64_t gpa, + uint64_t size) +{ + vm_mem_set_memory_attributes(vm, gpa, size, 0); +} + void vm_guest_mem_fallocate(struct kvm_vm *vm, uint64_t gpa, uint64_t size, bool punch_hole);
--
2.51.0.858.gf9c4a03a3a-goog