Kernel: Move FS-related files into Kernel/FileSystem/

Kernel/FileSystem/FileSystem.h

@@ -0,0 +1,174 @@
+#pragma once
+
+#include "DiskDevice.h"
+#include "InodeIdentifier.h"
+#include "InodeMetadata.h"
+#include "Limits.h"
+#include "UnixTypes.h"
+#include <AK/ByteBuffer.h>
+#include <AK/HashMap.h>
+#include <AK/OwnPtr.h>
+#include <AK/Retainable.h>
+#include <AK/RetainPtr.h>
+#include <AK/AKString.h>
+#include <AK/Function.h>
+#include <AK/kstdio.h>
+#include <Kernel/Lock.h>
+#include <AK/WeakPtr.h>
+#include <Kernel/KResult.h>
+
+static const dword mepoch = 476763780;
+
+class Inode;
+class FileDescriptor;
+class LocalSocket;
+class VMObject;
+
+class FS : public Retainable<FS> {
+    friend class Inode;
+public:
+    virtual ~FS();
+
+    unsigned fsid() const { return m_fsid; }
+    static FS* from_fsid(dword);
+    static void sync();
+
+    virtual bool initialize() = 0;
+    virtual const char* class_name() const = 0;
+    virtual InodeIdentifier root_inode() const = 0;
+
+    bool is_readonly() const { return m_readonly; }
+
+    virtual unsigned total_block_count() const { return 0; }
+    virtual unsigned free_block_count() const { return 0; }
+    virtual unsigned total_inode_count() const { return 0; }
+    virtual unsigned free_inode_count() const { return 0; }
+
+    struct DirectoryEntry {
+        DirectoryEntry(const char* name, InodeIdentifier, byte file_type);
+        DirectoryEntry(const char* name, size_t name_length, InodeIdentifier, byte file_type);
+        char name[256];
+        int name_length { 0 };
+        InodeIdentifier inode;
+        byte file_type { 0 };
+    };
+
+    virtual RetainPtr<Inode> create_inode(InodeIdentifier parentInode, const String& name, mode_t, unsigned size, int& error) = 0;
+    virtual RetainPtr<Inode> create_directory(InodeIdentifier parentInode, const String& name, mode_t, int& error) = 0;
+
+    virtual RetainPtr<Inode> get_inode(InodeIdentifier) const = 0;
+
+protected:
+    FS();
+
+    mutable Lock m_lock;
+
+private:
+    unsigned m_fsid { 0 };
+    bool m_readonly { false };
+};
+
+class Inode : public Retainable<Inode> {
+    friend class VFS;
+    friend class FS;
+public:
+    virtual ~Inode();
+
+    virtual void one_retain_left() { }
+
+    FS& fs() { return m_fs; }
+    const FS& fs() const { return m_fs; }
+    unsigned fsid() const;
+    unsigned index() const { return m_index; }
+
+    size_t size() const { return metadata().size; }
+    bool is_symlink() const { return metadata().is_symlink(); }
+    bool is_directory() const { return metadata().is_directory(); }
+    bool is_character_device() const { return metadata().is_character_device(); }
+    mode_t mode() const { return metadata().mode; }
+
+    InodeIdentifier identifier() const { return { fsid(), index() }; }
+    virtual InodeMetadata metadata() const = 0;
+
+    ByteBuffer read_entire(FileDescriptor* = nullptr) const;
+
+    virtual ssize_t read_bytes(off_t, ssize_t, byte* buffer, FileDescriptor*) const = 0;
+    virtual bool traverse_as_directory(Function<bool(const FS::DirectoryEntry&)>) const = 0;
+    virtual InodeIdentifier lookup(const String& name) = 0;
+    virtual String reverse_lookup(InodeIdentifier) = 0;
+    virtual ssize_t write_bytes(off_t, ssize_t, const byte* data, FileDescriptor*) = 0;
+    virtual KResult add_child(InodeIdentifier child_id, const String& name, byte file_type) = 0;
+    virtual KResult remove_child(const String& name) = 0;
+    virtual RetainPtr<Inode> parent() const = 0;
+    virtual size_t directory_entry_count() const = 0;
+    virtual KResult chmod(mode_t) = 0;
+    virtual KResult chown(uid_t, gid_t) = 0;
+    virtual KResult truncate(int) { return KSuccess; }
+
+    LocalSocket* socket() { return m_socket.ptr(); }
+    const LocalSocket* socket() const { return m_socket.ptr(); }
+    bool bind_socket(LocalSocket&);
+    bool unbind_socket();
+
+    bool is_metadata_dirty() const { return m_metadata_dirty; }
+
+    virtual int set_atime(time_t);
+    virtual int set_ctime(time_t);
+    virtual int set_mtime(time_t);
+    virtual int increment_link_count();
+    virtual int decrement_link_count();
+
+    virtual void flush_metadata() = 0;
+
+    void will_be_destroyed();
+
+    void set_vmo(VMObject&);
+    VMObject* vmo() { return m_vmo.ptr(); }
+    const VMObject* vmo() const { return m_vmo.ptr(); }
+
+protected:
+    Inode(FS& fs, unsigned index);
+    void set_metadata_dirty(bool b) { m_metadata_dirty = b; }
+    void inode_contents_changed(off_t, ssize_t, const byte*);
+    void inode_size_changed(size_t old_size, size_t new_size);
+
+    mutable Lock m_lock;
+
+private:
+    FS& m_fs;
+    unsigned m_index { 0 };
+    WeakPtr<VMObject> m_vmo;
+    RetainPtr<LocalSocket> m_socket;
+    bool m_metadata_dirty { false };
+};
+
+inline FS* InodeIdentifier::fs()
+{
+    return FS::from_fsid(m_fsid);
+}
+
+inline const FS* InodeIdentifier::fs() const
+{
+    return FS::from_fsid(m_fsid);
+}
+
+inline bool InodeIdentifier::is_root_inode() const
+{
+    return (*this) == fs()->root_inode();
+}
+
+inline unsigned Inode::fsid() const
+{
+    return m_fs.fsid();
+}
+
+namespace AK {
+
+template<>
+struct Traits<InodeIdentifier> {
+    static unsigned hash(const InodeIdentifier& inode) { return pair_int_hash(inode.fsid(), inode.index()); }
+    static void dump(const InodeIdentifier& inode) { kprintf("%02u:%08u", inode.fsid(), inode.index()); }
+};
+
+}
+