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If not, the operation fails. > > > > > > This is part of a patch series which eliminates the vmas parameter from the > > > GUP API, implementing the one remaining assertion within the entire kernel > > > that requires access to the VMAs associated with a GUP range. > > > > > > Signed-off-by: Lorenzo Stoakes > > > --- > > > include/linux/mm_types.h | 2 ++ > > > mm/gup.c | 16 ++++++++++++---- > > > 2 files changed, 14 insertions(+), 4 deletions(-) > > > > > > diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h > > > index 3fc9e680f174..84d1aec9dbab 100644 > > > --- a/include/linux/mm_types.h > > > +++ b/include/linux/mm_types.h > > > @@ -1185,6 +1185,8 @@ enum { > > > FOLL_PCI_P2PDMA = 1 << 10, > > > /* allow interrupts from generic signals */ > > > FOLL_INTERRUPTIBLE = 1 << 11, > > > + /* assert that the range spans VMAs with the same vma->vm_file */ > > > + FOLL_SAME_FILE = 1 << 12, > > > > I hope we don't add this flag, but it needs to be rejected in > > internal_get_user_pages_fast() > > > > intenal_get_user_pages_fast() checks against the complement of accepted > masks, therefore it will reject this as-is unless I'm missing > something. Hmm, yes, that looks OK > As for not adding the flag (an entirely understandable sentiment), it would > be good to get an insight into the semantics of what you feel would be more > suitable! I'm hoping there is not a solid justification for why io_uring is doing this check so we just delete it. Jason