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Commit a1ea9549 authored by Michel Lespinasse's avatar Michel Lespinasse Committed by Linus Torvalds
Browse files

mm: use mm_populate() for blocking remap_file_pages() 



Signed-off-by: default avatarMichel Lespinasse <walken@google.com>
Reviewed-by: default avatarRik van Riel <riel@redhat.com>
Tested-by: default avatarAndy Lutomirski <luto@amacapital.net>
Cc: Greg Ungerer <gregungerer@westnet.com.au>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent bebeb3d6

mm/fremap.c

+6 −16
Original line number Original line Diff line number Diff line
@@ -129,6 +129,7 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size, 
	struct vm_area_struct *vma;

	struct vm_area_struct *vma;

	int err = -EINVAL;

	int err = -EINVAL;

	int has_write_lock = 0;

	int has_write_lock = 0;

	vm_flags_t vm_flags;





	if (prot)

	if (prot)

		return err;

		return err;
@@ -228,30 +229,16 @@ get_write_lock: 
		/*

		/*

		 * drop PG_Mlocked flag for over-mapped range

		 * drop PG_Mlocked flag for over-mapped range

		 */

		 */

		vm_flags_t saved_flags = vma->vm_flags;

		if (!has_write_lock)

		if (!has_write_lock)

			goto get_write_lock;

			goto get_write_lock;

		vm_flags = vma->vm_flags;

		munlock_vma_pages_range(vma, start, start + size);

		munlock_vma_pages_range(vma, start, start + size);

		vma->vm_flags = saved_flags;

		vma->vm_flags = vm_flags;

	}

	}





	mmu_notifier_invalidate_range_start(mm, start, start + size);

	mmu_notifier_invalidate_range_start(mm, start, start + size);

	err = vma->vm_ops->remap_pages(vma, start, size, pgoff);

	err = vma->vm_ops->remap_pages(vma, start, size, pgoff);

	mmu_notifier_invalidate_range_end(mm, start, start + size);

	mmu_notifier_invalidate_range_end(mm, start, start + size);

	if (!err) {

		if (vma->vm_flags & VM_LOCKED) {

			/*

			 * might be mapping previously unmapped range of file

			 */

			mlock_vma_pages_range(vma, start, start + size);

		} else if (!(flags & MAP_NONBLOCK)) {

			if (unlikely(has_write_lock)) {

				downgrade_write(&mm->mmap_sem);

				has_write_lock = 0;

			}

			make_pages_present(start, start+size);

		}

	}





	/*

	/*

	 * We can't clear VM_NONLINEAR because we'd have to do

	 * We can't clear VM_NONLINEAR because we'd have to do
@@ -260,10 +247,13 @@ get_write_lock: 
	 */

	 */





out:

out:

	vm_flags = vma->vm_flags;

	if (likely(!has_write_lock))

	if (likely(!has_write_lock))

		up_read(&mm->mmap_sem);

		up_read(&mm->mmap_sem);

	else

	else

		up_write(&mm->mmap_sem);

		up_write(&mm->mmap_sem);

	if (!err && ((vm_flags & VM_LOCKED) || !(flags & MAP_NONBLOCK)))

		mm_populate(start, size);





	return err;

	return err;

}
 
}