Add a rough draft of the sysscall interface.

Just a LaTeX document containing the basics of the syscall interface.

paper/redox.tex

@@ -0,0 +1,85 @@
+\documentclass[11pt]{article}
+\usepackage[T1]{fontenc}
+\usepackage{amsmath, amsfonts, amssymb, amsthm, url, algorithmicx,
+    algpseudocode, lmodern, color, graphicx}
+
+\title{Redox and system calls -- a multi-level kernel space}
+\author{Redox OS developers}
+\date{\today}
+
+\begin{document}
+    \maketitle
+
+    %%% DISCLAIMER %%%
+
+    \begin{titlepage}
+        \centering \huge\bfseries The following document is an incomplete draft.
+    \end{titlepage}
+
+    %%% START OF DOCUMENT %%%
+
+    \maketitle
+
+    \begin{abstract}
+        In this paper, we review Redox's core system call interface. Redox has
+        multiple levels of kernel space, and the top one consists of a very
+        minimal system call interface, which we go over here.
+    \end{abstract}
+
+    \section{Introduction}
+    TODO
+
+    \section{Executing system calls}
+    We allow multiplied system calls, a generalized version of concept of
+    multicalls in the \emph{kqueue} system call.
+
+    Depending on the platform, system calls might be sent through interrupts or
+    \texttt{sysenter}. What we are really interested in, though, is the state
+    when we leave user space.
+
+    \begin{description}
+        \item [\texttt{rax}/\texttt{eax}] stores the pointer to the array of system calls.
+        \item [\texttt{rbx}/\texttt{ebx}] stores the number of system calls in
+            this bundle.
+    \end{description}
+
+    \section{The interface}
+    Each entry in this system call bundle buffer needs an ABI representation.
+    We represent the interface for the \emph{core system calls}.
+
+    The representation is as follows:
+
+    \begin{description}
+        \item [The system call ID] this is an unsigned 16-bit integer
+            representing which system call is used.
+        \item [First argument] this 64-bit integer is used as defined by the
+            system call.
+        \item [Second argument] this 64-bit integer is used as defined by the
+            system call.
+    \end{description}
+
+    The return value of the system call is placed in the respective element.
+
+    \subsection{Access management}
+    The memory access management is a set of system calls taken pointer and
+    size, respectively.
+
+    It contains of four calls:
+
+    \begin{description}
+        \item [Make memory readable].
+        \item [Make memory unreadable].
+        \item [Make memory writable].
+        \item [Make memory unwritable].
+        \item [Make memory executable].
+        \item [Make memory unexecutable].
+    \end{description}
+
+    \subsection{Access management}
+
+    %%% BIBLIOGRAPHY %%%
+
+    \begin{thebibliography}{9}
+        TODO
+    \end{thebibliography}
+\end{document}