On Wed, Jan 10, 2024 at 05:20:28PM +0800, Chen Haixiang wrote:
> +++ b/include/linux/mm.h
> @@ -573,6 +573,7 @@ struct vm_operations_struct {
> unsigned long end, unsigned long newflags);
> vm_fault_t (*fault)(struct vm_fault *vmf);
> vm_fault_t (*huge_fault)(struct vm_fault *vmf, unsigned int order);
> + vm_fault_t (*shmem_huge_fault)(struct vm_fault *vmf, pmd_t orig_pmd);
No new operation for this.
> +++ b/mm/memory.c
> @@ -4942,6 +4942,13 @@ static inline vm_fault_t wp_huge_pmd(struct vm_fault *vmf)
> }
> }
>
> + if (vmf->vma->vm_ops->shmem_huge_fault) {
> + vm_fault_t ret = vmf->vma->vm_ops->shmem_huge_fault(vmf, vmf->orig_pmd);
> +
> + if (!(ret & VM_FAULT_FALLBACK))
> + return ret;
> + }
Why would you do this when ->huge_fault is called in the stanza above?
