Now we have the expressive vma_is_kernel_owned() and vma_is_fixed_mapping()
predicates, use them to determine whether to proceed with migration. This
drops the VMA_IO_BIT test, which is safe as only kernel-owned mappings may
set it.

hugetlb mappings remain excluded, as they are fixed mappings.

No functional change intended.

Signed-off-by: Lorenzo Stoakes (ARM) <[email protected]>
---
 mm/migrate_device.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/mm/migrate_device.c b/mm/migrate_device.c
index b9c453c28795..b74c0ae42768 100644
--- a/mm/migrate_device.c
+++ b/mm/migrate_device.c
@@ -739,19 +739,21 @@ static void migrate_vma_unmap(struct migrate_vma *migrate)
  */
 int migrate_vma_setup(struct migrate_vma *args)
 {
+       const struct vm_area_struct *vma = args->vma;
        long nr_pages = (args->end - args->start) >> PAGE_SHIFT;
 
        args->start &= PAGE_MASK;
        args->end &= PAGE_MASK;
-       if (!args->vma || vma_test_any_mask(args->vma, VMA_SPECIAL_FLAGS) ||
-           vma_is_dax(args->vma))
+       if (!vma)
+               return -EINVAL;
+       if (vma_is_kernel_owned(vma) || vma_is_fixed_mapping(vma) ||
+           vma_is_dax(vma))
                return -EINVAL;
        if (nr_pages <= 0)
                return -EINVAL;
-       if (args->start < args->vma->vm_start ||
-           args->start >= args->vma->vm_end)
+       if (args->start < vma->vm_start || args->start >= vma->vm_end)
                return -EINVAL;
-       if (args->end <= args->vma->vm_start || args->end > args->vma->vm_end)
+       if (args->end <= vma->vm_start || args->end > vma->vm_end)
                return -EINVAL;
        if (!args->src || !args->dst)
                return -EINVAL;

-- 
2.55.0


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