This will used by guest_memfd in a later patch.
Signed-off-by: Ackerley Tng ackerleytng@google.com --- fs/hugetlbfs/inode.c | 33 +++++---------------------------- include/linux/hugetlb.h | 3 +++ mm/hugetlb.c | 21 +++++++++++++++++++++ 3 files changed, 29 insertions(+), 28 deletions(-)
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index 300a6ef300c1..f76001418672 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -720,29 +720,6 @@ static void hugetlb_vmtruncate(struct inode *inode, loff_t offset) remove_inode_hugepages(inode, offset, LLONG_MAX); }
-static void hugetlbfs_zero_partial_page(struct hstate *h, - struct address_space *mapping, - loff_t start, - loff_t end) -{ - pgoff_t idx = start >> huge_page_shift(h); - struct folio *folio; - - folio = filemap_lock_hugetlb_folio(h, mapping, idx); - if (IS_ERR(folio)) - return; - - start = start & ~huge_page_mask(h); - end = end & ~huge_page_mask(h); - if (!end) - end = huge_page_size(h); - - folio_zero_segment(folio, (size_t)start, (size_t)end); - - folio_unlock(folio); - folio_put(folio); -} - static long hugetlbfs_punch_hole(struct inode *inode, loff_t offset, loff_t len) { struct hugetlbfs_inode_info *info = HUGETLBFS_I(inode); @@ -768,9 +745,10 @@ static long hugetlbfs_punch_hole(struct inode *inode, loff_t offset, loff_t len) i_mmap_lock_write(mapping);
/* If range starts before first full page, zero partial page. */ - if (offset < hole_start) - hugetlbfs_zero_partial_page(h, mapping, - offset, min(offset + len, hole_start)); + if (offset < hole_start) { + hugetlb_zero_partial_page(h, mapping, offset, + min(offset + len, hole_start)); + }
/* Unmap users of full pages in the hole. */ if (hole_end > hole_start) { @@ -782,8 +760,7 @@ static long hugetlbfs_punch_hole(struct inode *inode, loff_t offset, loff_t len)
/* If range extends beyond last full page, zero partial page. */ if ((offset + len) > hole_end && (offset + len) > hole_start) - hugetlbfs_zero_partial_page(h, mapping, - hole_end, offset + len); + hugetlb_zero_partial_page(h, mapping, hole_end, offset + len);
i_mmap_unlock_write(mapping);
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 4d47bf94c211..752062044b0b 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -124,6 +124,9 @@ long hugepage_subpool_put_pages(struct hugepage_subpool *spool, long delta);
int hugetlb_acct_memory(struct hstate *h, long delta);
+void hugetlb_zero_partial_page(struct hstate *h, struct address_space *mapping, + loff_t start, loff_t end); + void hugetlb_dup_vma_private(struct vm_area_struct *vma); void clear_vma_resv_huge_pages(struct vm_area_struct *vma); int move_hugetlb_page_tables(struct vm_area_struct *vma, diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 5a37b03e1361..372d8294fb2f 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1989,6 +1989,27 @@ void free_huge_folio(struct folio *folio) } }
+void hugetlb_zero_partial_page(struct hstate *h, struct address_space *mapping, + loff_t start, loff_t end) +{ + pgoff_t idx = start >> huge_page_shift(h); + struct folio *folio; + + folio = filemap_lock_hugetlb_folio(h, mapping, idx); + if (IS_ERR(folio)) + return; + + start = start & ~huge_page_mask(h); + end = end & ~huge_page_mask(h); + if (!end) + end = huge_page_size(h); + + folio_zero_segment(folio, (size_t)start, (size_t)end); + + folio_unlock(folio); + folio_put(folio); +} + /* * Must be called with the hugetlb lock held */