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