mm/gup: follow_pfn_pte(): -EEXIST cleanup

Remove a quirky special case from follow_pfn_pte(), and adjust its
callers to match.  Caller changes include:

__get_user_pages(): Regardless of any FOLL_* flags, get_user_pages() and
its variants should handle PFN-only entries by stopping early, if the
caller expected **pages to be filled in.  This makes for a more reliable
API, as compared to the previous approach of skipping over such entries
(and thus leaving them silently unwritten).

move_pages(): squash the -EEXIST error return from follow_page() into
-EFAULT, because -EFAULT is listed in the man page, whereas -EEXIST is
not.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: John Hubbard <[email protected]>
Suggested-by: Jason Gunthorpe <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Cc: Peter Xu <[email protected]>
Cc: Lukas Bulwahn <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Claudio Imbrenda <[email protected]>
Cc: Alex Williamson <[email protected]>
Cc: Andrea Arcangeli <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions