Kernel: Changed stat values from func to be field

- Removed virtual functions for all of the stat stuff.
This did however introduce some issues, mainly with /proc
becoming out of sync if you changed your ID. I propose we
do the linux thing and just have a stat update function
which is optional, but allows dynamic updates of stat fields
for cases such as those in uid/gid in /proc.
- Simplified the API, although still kind of annoying
it is a bit simpler.
- Moved some of the FS structure from having the FS inode inside
the in memory inode to a Serialise <-> Deserialise model where
Inodes are deserialised from disk into in memory ones and then
back into on disk ones when it comes time for syncing.
This makes it semantically better in my opinion, as it explicitly
separates disk and non-disk functionality.

kernel/include/kernel/FS/ProcFS/Inode.h

@@ -9,34 +9,27 @@ namespace Kernel
 
 	class ProcPidInode final : public TmpDirectoryInode
 	{
+		// FIXME: dynamically update ruid/rgid.
+		// Possibly just have a magic uid/gid of -1 or something
+		// which means use current process ID
 	public:
 		static BAN::ErrorOr<BAN::RefPtr<ProcPidInode>> create_new(Process&, TmpFileSystem&, mode_t);
 		~ProcPidInode() = default;
 
-		virtual uid_t uid() const override { return m_process.credentials().ruid(); }
-		virtual gid_t gid() const override { return m_process.credentials().rgid(); }
-
 		void cleanup();
-
 	protected:
 		virtual BAN::ErrorOr<void> unlink_impl(BAN::StringView) override { return BAN::Error::from_errno(EPERM); }
 
 	private:
 		ProcPidInode(Process&, TmpFileSystem&, const TmpInodeInfo&);
-
-	private:
-		Process& m_process;
 	};
 
 	class ProcROProcessInode final : public TmpInode
 	{
+		//FIXME: dynamically update ruid/rgid
 	public:
 		static BAN::ErrorOr<BAN::RefPtr<ProcROProcessInode>> create_new(Process&, size_t (Process::*callback)(off_t, BAN::ByteSpan) const, TmpFileSystem&, mode_t);
 		~ProcROProcessInode() = default;
-
-		virtual uid_t uid() const override { return m_process.credentials().ruid(); }
-		virtual gid_t gid() const override { return m_process.credentials().rgid(); }
-
 	protected:
 		virtual BAN::ErrorOr<size_t> read_impl(off_t, BAN::ByteSpan) override;
 
@@ -59,13 +52,11 @@ namespace Kernel
 
 	class ProcSymlinkProcessInode final : public TmpInode
 	{
+		//FIXME: dynamically update ruid/rgid
 	public:
 		static BAN::ErrorOr<BAN::RefPtr<ProcSymlinkProcessInode>> create_new(Process& process, BAN::ErrorOr<BAN::String> (Process::*callback)() const, TmpFileSystem&, mode_t);
 		~ProcSymlinkProcessInode() = default;
 
-		virtual uid_t uid() const override { return m_process.credentials().ruid(); }
-		virtual gid_t gid() const override { return m_process.credentials().rgid(); }
-
 	protected:
 		virtual BAN::ErrorOr<BAN::String> link_target_impl() override;
 
@@ -132,13 +123,10 @@ namespace Kernel
 
 	class ProcFDDirectoryInode final : public TmpInode
 	{
+		//FIXME: dynamically update ruid/rgid
 	public:
 		static BAN::ErrorOr<BAN::RefPtr<ProcFDDirectoryInode>> create_new(Process&, TmpFileSystem&, mode_t);
 		~ProcFDDirectoryInode() = default;
-
-		virtual uid_t uid() const override { return m_process.credentials().ruid(); }
-		virtual gid_t gid() const override { return m_process.credentials().rgid(); }
-
 	protected:
 		virtual BAN::ErrorOr<BAN::RefPtr<Inode>> find_inode_impl(BAN::StringView) override;
 		virtual BAN::ErrorOr<size_t> list_next_inodes_impl(off_t, struct dirent*, size_t) override;