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Suggested-by: Al Viro Signed-off-by: Jens Axboe --- include/linux/uio.h | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/include/linux/uio.h b/include/linux/uio.h index 00cebe2b70de..9e9510672b28 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -197,6 +197,16 @@ size_t copy_to_iter(const void *addr, size_t bytes, st= ruct iov_iter *i) return 0; } =20 +static __always_inline __must_check +bool copy_to_iter_full(const void *addr, size_t bytes, struct iov_iter *i) +{ + size_t copied =3D copy_to_iter(addr, bytes, i); + if (likely(copied =3D=3D bytes)) + return true; + iov_iter_revert(i, copied); + return false; +} + static __always_inline __must_check size_t copy_from_iter(void *addr, size_t bytes, struct iov_iter *i) { --=20 2.43.0