Commit f9d86a60 authored by Wei Yang's avatar Wei Yang Committed by Linus Torvalds
Browse files

mm/mmap: leave adjust_next as virtual address instead of page frame number 



Instead of converting adjust_next between bytes and pages number, let's
just store the virtual address into adjust_next.

Also, this patch fixes one typo in the comment of vma_adjust_trans_huge().

[vbabka@suse.cz: changelog tweak]

Signed-off-by: default avatarWei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Link: http://lkml.kernel.org/r/20200828081031.11306-1-richard.weiyang@linux.alibaba.com


Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent a08d93e5

mm/huge_memory.c

+2 −2
Original line number Diff line number Diff line
@@ -2306,13 +2306,13 @@ void vma_adjust_trans_huge(struct vm_area_struct *vma, 


	/*

	 * If we're also updating the vma->vm_next->vm_start, if the new

	 * vm_next->vm_start isn't page aligned and it could previously

	 * vm_next->vm_start isn't hpage aligned and it could previously

	 * contain an hugepage: check if we need to split an huge pmd.

	 */

	if (adjust_next > 0) {

		struct vm_area_struct *next = vma->vm_next;

		unsigned long nstart = next->vm_start;

		nstart += adjust_next << PAGE_SHIFT;

		nstart += adjust_next;

		if (nstart & ~HPAGE_PMD_MASK &&

		    (nstart & HPAGE_PMD_MASK) >= next->vm_start &&

		    (nstart & HPAGE_PMD_MASK) + HPAGE_PMD_SIZE <= next->vm_end)

mm/mmap.c

+4 −4
Original line number Diff line number Diff line
@@ -758,7 +758,7 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, 
			 * vma expands, overlapping part of the next:

			 * mprotect case 5 shifting the boundary up.

			 */

			adjust_next = (end - next->vm_start) >> PAGE_SHIFT;

			adjust_next = (end - next->vm_start);

			exporter = next;

			importer = vma;

			VM_WARN_ON(expand != importer);
@@ -768,7 +768,7 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, 
			 * split_vma inserting another: so it must be

			 * mprotect case 4 shifting the boundary down.

			 */

			adjust_next = -((vma->vm_end - end) >> PAGE_SHIFT);

			adjust_next = -(vma->vm_end - end);

			exporter = vma;

			importer = next;

			VM_WARN_ON(expand != importer);
@@ -840,8 +840,8 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, 
	}

	vma->vm_pgoff = pgoff;

	if (adjust_next) {

		next->vm_start += adjust_next << PAGE_SHIFT;

		next->vm_pgoff += adjust_next;

		next->vm_start += adjust_next;

		next->vm_pgoff += adjust_next >> PAGE_SHIFT;

	}



	if (root) {