kernel/linux.git/include/linux/sunrpc/xdrgen, branch v6.13.2

xdrgen: Keep track of on-the-wire data type widths

2024-11-11T18:42:01+00:00

The generic parts of the RPC layer need to know the widths (in XDR_UNIT increments) of the XDR data types defined for each protocol. As a first step, add dictionaries to keep track of the symbolic and actual maximum XDR width of XDR types. This makes it straightforward to look up the width of a type by its name. The built-in dictionaries are pre-loaded with the widths of the built-in XDR types as defined in RFC 4506. Signed-off-by: Chuck Lever

xdrgen: Fix return code checking in built-in XDR decoders

2024-09-20T23:31:39+00:00

xdr_stream_encode_u32() returns XDR_UNIT on success. xdr_stream_decode_u32() returns zero or -EMSGSIZE, but never XDR_UNIT. Signed-off-by: Chuck Lever

tools: Add xdrgen

2024-09-20T23:31:39+00:00

Add a Python-based tool for translating XDR specifications into XDR encoder and decoder functions written in the Linux kernel's C coding style. The generator attempts to match the usual C coding style of the Linux kernel's SunRPC consumers. This approach is similar to the netlink code generator in tools/net/ynl . The maintainability benefits of machine-generated XDR code include: - Stronger type checking - Reduces the number of bugs introduced by human error - Makes the XDR code easier to audit and analyze - Enables rapid prototyping of new RPC-based protocols - Hardens the layering between protocol logic and marshaling - Makes it easier to add observability on demand - Unit tests might be built for both the tool and (automatically) for the generated code In addition, converting the XDR layer to use memory-safe languages such as Rust will be easier if much of the code can be converted automatically. Tested-by: Jeff Layton Signed-off-by: Chuck Lever