file: Add RCU implementation of the file descriptor table

Signed-off-by: Pedro Falcato <[email protected]>

kernel/include/onyx/ioctx.h

@@ -1,30 +1,38 @@
 /*
- * Copyright (c) 2016, 2017 Pedro Falcato
+ * Copyright (c) 2016 - 2023 Pedro Falcato
  * This file is part of Onyx, and is released under the terms of the MIT License
  * check LICENSE at the root directory for more information
+ *
+ * SPDX-License-Identifier: MIT
  */
 #ifndef _IOCTX_H
 #define _IOCTX_H
 
-#include <onyx/types.h>
-
 #include <onyx/file.h>
 #include <onyx/mutex.h>
+#include <onyx/rcupdate.h>
+#include <onyx/types.h>
 #include <onyx/vfs.h>
 
 #define FDS_PER_LONG            (sizeof(unsigned long) * 8)
 #define FILE_DESCRIPTOR_GROW_NR (FDS_PER_LONG)
 
+struct fd_table
+{
+    struct file **file_desc{nullptr};
+    unsigned int file_desc_entries{};
+    unsigned long *cloexec_fds{};
+    unsigned long *open_fds{};
+    struct rcu_head rcuhead;
+};
+
 struct ioctx
 {
     /* Current working directory */
     spinlock cwd_lock{};
     file *cwd{};
     spinlock fdlock{};
-    struct file **file_desc{};
-    unsigned int file_desc_entries{};
-    unsigned long *cloexec_fds{};
-    unsigned long *open_fds{};
+    fd_table __rcu *table{};
     mode_t umask{};
 };
 

kernel/include/onyx/vfs.h

@@ -15,6 +15,7 @@
 
 #include <onyx/mm/vm_object.h>
 #include <onyx/object.h>
+#include <onyx/rcupdate.h>
 #include <onyx/rwlock.h>
 #include <onyx/superblock.h>
 #include <onyx/vm.h>
@@ -152,7 +153,10 @@ struct file
     struct inode *f_ino;
     unsigned int f_flags;
     struct dentry *f_dentry;
-    void *private_data;
+    union {
+        void *private_data;
+        struct rcu_head rcuhead;
+    };
 };
 
 int inode_create_vmo(struct inode *ino);