rust: error: Add Error::from_errno{_unchecked}()

Add a function to create `Error` values out of a kernel error return,
which safely upholds the invariant that the error code is well-formed
(negative and greater than -MAX_ERRNO). If a malformed code is passed
in, it will be converted to EINVAL.

Lina: Imported from rust-for-linux/rust as authored by Miguel and Fox
with refactoring from Wedson, renamed from_kernel_errno() to
from_errno().

Co-developed-by: Fox Chen <[email protected]>
Signed-off-by: Fox Chen <[email protected]>
Co-developed-by: Wedson Almeida Filho <[email protected]>
Signed-off-by: Wedson Almeida Filho <[email protected]>
Signed-off-by: Miguel Ojeda <[email protected]>
Reviewed-by: Andreas Hindborg <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Reviewed-by: Martin Rodriguez Reboredo <[email protected]>
Signed-off-by: Asahi Lina <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Mark the new associated functions as `#[allow(dead_code)]`. ]
Signed-off-by: Miguel Ojeda <[email protected]>

0 files changed, 0 insertions, 0 deletions