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, 0 insertions, 37 deletions

diff --git a/linux/preempt.c b/linux/preempt.c
deleted file mode 100644
index 72eceed3..00000000
--- a/linux/preempt.c
+++ /dev/null
@@ -1,37 +0,0 @@
-#include <pthread.h>
-
-#include "linux/preempt.h"
-
-/*
- * In userspace, pthreads are preemptible and can migrate CPUs at any time.
- *
- * In the kernel, preempt_disable() logic essentially guarantees that a marked
- * critical section owns its CPU for the relevant block. This is necessary for
- * various code paths, critically including the percpu system as it allows for
- * non-atomic reads and writes to CPU-local data structures.
- *
- * The high performance userspace equivalent would be to use thread local
- * storage to replace percpu data, but that would be complicated. It should be
- * correct to instead guarantee mutual exclusion for the critical sections.
- */
-
-static pthread_mutex_t preempt_lock;
-
-__attribute__((constructor))
-static void preempt_init(void) {
-	pthread_mutexattr_t attr;
-	pthread_mutexattr_init(&attr);
-	pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
-	pthread_mutex_init(&preempt_lock, &attr);
-	pthread_mutexattr_destroy(&attr);
-}
-
-void preempt_disable(void)
-{
-	pthread_mutex_lock(&preempt_lock);
-}
-
-void preempt_enable(void)
-{
-	pthread_mutex_unlock(&preempt_lock);
-}