kernel: add futex definitions

include/kernel/futex.h

@@ -0,0 +1,26 @@
+#ifndef KERNEL_FUTEX_H_
+#define KERNEL_FUTEX_H_
+
+#include <kernel/btree.h>
+#include <kernel/wait.h>
+#include <mango/types.h>
+
+struct address_space;
+
+typedef phys_addr_t futex_key_t;
+
+struct futex {
+	struct btree_node f_node;
+	futex_key_t f_key;
+	struct waitqueue f_waiters;
+};
+
+extern kern_status_t futex_init(void);
+extern kern_status_t futex_get(
+	struct address_space *space,
+	kern_futex_t *futex,
+	futex_key_t *out);
+extern kern_status_t futex_wait(futex_key_t futex, kern_futex_t new_val);
+extern kern_status_t futex_wake(futex_key_t futex, size_t nwaiters);
+
+#endif

kernel/futex.c

@@ -0,0 +1,70 @@
+#include <kernel/address-space.h>
+#include <kernel/futex.h>
+#include <mango/status.h>
+
+enum futex_flags {
+	FUTEX_CREATE = 0x01u,
+};
+
+static struct btree futex_list = {0};
+static spin_lock_t futex_list_lock = SPIN_LOCK_INIT;
+
+static struct vm_cache futex_cache = {
+	.c_name = "futex",
+	.c_obj_size = sizeof(struct futex),
+};
+
+BTREE_DEFINE_SIMPLE_INSERT(struct futex, f_node, f_key, put_futex)
+BTREE_DEFINE_SIMPLE_GET(struct futex, futex_key_t, f_node, f_key, get_futex)
+
+kern_status_t futex_init(void)
+{
+	vm_cache_init(&futex_cache);
+	return KERN_OK;
+}
+
+static struct futex *get_data(futex_key_t key, enum futex_flags flags)
+{
+	spin_lock(&futex_list_lock);
+	struct futex *futex = get_futex(&futex_list, key);
+	spin_unlock(&futex_list_lock);
+
+	if (!futex && !(flags & FUTEX_CREATE)) {
+		return NULL;
+	}
+
+	futex = vm_cache_alloc(&futex_cache, VM_NORMAL);
+	futex->f_key = key;
+
+	spin_lock(&futex_list_lock);
+	put_futex(&futex_list, futex);
+	spin_unlock(&futex_list_lock);
+
+	return futex;
+}
+
+kern_status_t futex_get(
+	struct address_space *space,
+	kern_futex_t *futex,
+	futex_key_t *out)
+{
+	unsigned long flags;
+	address_space_lock_irqsave(space, &flags);
+	kern_status_t status = address_space_translate(
+		space,
+		(virt_addr_t)futex,
+		out,
+		&flags);
+	address_space_unlock_irqrestore(space, flags);
+	return status;
+}
+
+kern_status_t futex_wait(futex_key_t futex, kern_futex_t new_val)
+{
+	return KERN_UNIMPLEMENTED;
+}
+
+kern_status_t futex_wake(futex_key_t futex, size_t nwaiters)
+{
+	return KERN_UNIMPLEMENTED;
+}

libmango/include/mango/types.h

@@ -46,20 +46,16 @@
 
 #define IOVEC(p, len)                                                          \
 	{                                                                      \
-		.io_base = (virt_addr_t)(p),                                   \
-		.io_len = (len),                                               \
+		.io_base = (virt_addr_t)(p), .io_len = (len),                  \
 	}
 #define MSG_HANDLE(mode, value)                                                \
 	{                                                                      \
-		.hnd_mode = (mode),                                            \
-		.hnd_value = (value),                                          \
+		.hnd_mode = (mode), .hnd_value = (value),                      \
 	}
 #define MSG(data, data_count, handles, handles_len)                            \
 	{                                                                      \
-		.msg_data = (data),                                            \
-		.msg_data_count = (data_count),                                \
-		.msg_handles = (handles),                                      \
-		.msg_handles_count = (handles_len),                            \
+		.msg_data = (data), .msg_data_count = (data_count),            \
+		.msg_handles = (handles), .msg_handles_count = (handles_len),  \
 	}
 
 typedef uintptr_t phys_addr_t;
@@ -75,6 +71,7 @@ typedef uint32_t kern_handle_t;
 typedef uint32_t kern_config_key_t;
 typedef uint32_t vm_prot_t;
 typedef int64_t ssize_t;
+typedef uint32_t kern_futex_t;
 
 typedef unsigned short equeue_packet_type_t;