Commit 7dac0ec8 authored by Vishal Moola (Oracle)'s avatar Vishal Moola (Oracle) Committed by Andrew Morton
Browse files

hugetlb: pass struct vm_fault through to hugetlb_handle_userfault() 

Now that hugetlb_fault() has a struct vm_fault, have
hugetlb_handle_userfault() use it instead of creating one of its own.

This lets us reduce the number of arguments passed to
hugetlb_handle_userfault() from 7 to 3, cleaning up the code and stack.

Link: https://lkml.kernel.org/r/20240221234732.187629-4-vishal.moola@gmail.com


Signed-off-by: default avatarVishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 0ca22723

mm/hugetlb.c

+9 −29
Original line number Diff line number Diff line
@@ -6085,39 +6085,21 @@ int hugetlb_add_to_page_cache(struct folio *folio, struct address_space *mapping 
	return 0;

}



static inline vm_fault_t hugetlb_handle_userfault(struct vm_area_struct *vma,

static inline vm_fault_t hugetlb_handle_userfault(struct vm_fault *vmf,

						  struct address_space *mapping,

						  pgoff_t idx,

						  unsigned int flags,

						  unsigned long haddr,

						  unsigned long addr,

						  unsigned long reason)

{

	u32 hash;

	struct vm_fault vmf = {

		.vma = vma,

		.address = haddr,

		.real_address = addr,

		.flags = flags,



		/*

		 * Hard to debug if it ends up being

		 * used by a callee that assumes

		 * something about the other

		 * uninitialized fields... same as in

		 * memory.c

		 */

	};



	/*

	 * vma_lock and hugetlb_fault_mutex must be dropped before handling

	 * userfault. Also mmap_lock could be dropped due to handling

	 * userfault, any vma operation should be careful from here.

	 */

	hugetlb_vma_unlock_read(vma);

	hash = hugetlb_fault_mutex_hash(mapping, idx);

	hugetlb_vma_unlock_read(vmf->vma);

	hash = hugetlb_fault_mutex_hash(mapping, vmf->pgoff);

	mutex_unlock(&hugetlb_fault_mutex_table[hash]);

	return handle_userfault(&vmf, reason);

	return handle_userfault(vmf, reason);

}



/*
@@ -6141,7 +6123,8 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm, 
			struct vm_area_struct *vma,

			struct address_space *mapping, pgoff_t idx,

			unsigned long address, pte_t *ptep,

			pte_t old_pte, unsigned int flags)

			pte_t old_pte, unsigned int flags,

			struct vm_fault *vmf)

{

	struct hstate *h = hstate_vma(vma);

	vm_fault_t ret = VM_FAULT_SIGBUS;
@@ -6200,8 +6183,7 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm, 
				goto out;

			}



			return hugetlb_handle_userfault(vma, mapping, idx, flags,

							haddr, address,

			return hugetlb_handle_userfault(vmf, mapping,

							VM_UFFD_MISSING);

		}
@@ -6273,8 +6255,7 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm, 
				ret = 0;

				goto out;

			}

			return hugetlb_handle_userfault(vma, mapping, idx, flags,

							haddr, address,

			return hugetlb_handle_userfault(vmf, mapping,

							VM_UFFD_MINOR);

		}

	}
@@ -6444,9 +6425,8 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, 
		 * hugetlb_no_page will drop vma lock and hugetlb fault

		 * mutex internally, which make us return immediately.

		 */



		return hugetlb_no_page(mm, vma, mapping, vmf.pgoff, address,

					ptep, entry, flags);

					ptep, entry, flags, &vmf);

	}



	ret = 0;