Add support for sending a pagefault event if userfaultfd is registered. Only page minor event is currently supported.
Signed-off-by: Nikita Kalyazin kalyazin@amazon.com --- virt/kvm/guest_memfd.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c index 26b1734b9623..92d3e6b51dc2 100644 --- a/virt/kvm/guest_memfd.c +++ b/virt/kvm/guest_memfd.c @@ -4,6 +4,9 @@ #include <linux/kvm_host.h> #include <linux/pagemap.h> #include <linux/anon_inodes.h> +#ifdef CONFIG_KVM_PRIVATE_MEM +#include <linux/userfaultfd_k.h> +#endif /* CONFIG_KVM_PRIVATE_MEM */
#include "kvm_mm.h"
@@ -380,6 +383,13 @@ static vm_fault_t kvm_gmem_fault(struct vm_fault *vmf) kvm_gmem_mark_prepared(folio); }
+ if (userfaultfd_minor(vmf->vma) && + !(vmf->flags & FAULT_FLAG_NO_USERFAULT_MINOR)) { + folio_unlock(folio); + filemap_invalidate_unlock_shared(inode->i_mapping); + return handle_userfault(vmf, VM_UFFD_MINOR); + } + vmf->page = folio_file_page(folio, vmf->pgoff);
out_folio: