move Rust sources to top level, C sources into c_src

This moves the Rust sources out of rust_src/ and into the top level.
Running the bcachefs executable out of the development tree is now:

$ ./target/release/bcachefs command
or
$ cargo run --profile release -- command

instead of "./bcachefs command".

Building and installing is still:

$ make && make install

Signed-off-by: Thomas Bertschinger <tahbertschinger@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

1 files changed, 11 insertions, 0 deletions

diff --git a/c_src/include/linux/crc64.h b/c_src/include/linux/crc64.h
new file mode 100644
index 00000000..c756e65a
--- /dev/null
+++ b/c_src/include/linux/crc64.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * See lib/crc64.c for the related specification and polynomial arithmetic.
+ */
+#ifndef _LINUX_CRC64_H
+#define _LINUX_CRC64_H
+
+#include <linux/types.h>
+
+u64 __pure crc64_be(u64 crc, const void *p, size_t len);
+#endif /* _LINUX_CRC64_H */