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, 45 insertions, 0 deletions

diff --git a/c_src/include/linux/backing-dev.h b/c_src/include/linux/backing-dev.h
new file mode 100644
index 00000000..d8a86b45
--- /dev/null
+++ b/c_src/include/linux/backing-dev.h
@@ -0,0 +1,45 @@
+#ifndef _LINUX_BACKING_DEV_H
+#define _LINUX_BACKING_DEV_H
+
+#include <linux/list.h>
+
+typedef int (congested_fn)(void *, int);
+
+enum wb_congested_state {
+	WB_async_congested,	/* The async (write) queue is getting full */
+	WB_sync_congested,	/* The sync queue is getting full */
+};
+
+struct backing_dev_info {
+	struct list_head bdi_list;
+	unsigned	ra_pages;
+	unsigned	capabilities;
+
+	congested_fn	*congested_fn;
+	void		*congested_data;
+};
+
+#define BDI_CAP_NO_ACCT_DIRTY	0x00000001
+#define BDI_CAP_NO_WRITEBACK	0x00000002
+#define BDI_CAP_NO_ACCT_WB	0x00000004
+#define BDI_CAP_STABLE_WRITES	0x00000008
+#define BDI_CAP_STRICTLIMIT	0x00000010
+#define BDI_CAP_CGROUP_WRITEBACK 0x00000020
+
+static inline int bdi_congested(struct backing_dev_info *bdi, int cong_bits)
+{
+	return 0;
+}
+
+static inline int __must_check bdi_setup_and_register(struct backing_dev_info *bdi,
+						      char *name)
+{
+	bdi->capabilities = 0;
+	return 0;
+}
+
+static inline void bdi_destroy(struct backing_dev_info *bdi) {}
+
+#define VM_MAX_READAHEAD	128	/* kbytes */
+
+#endif	/* _LINUX_BACKING_DEV_H */