From 2ca95dc97c9dd591d0f71f1f4c411b3aeb82d690 Mon Sep 17 00:00:00 2001 From: Ben Pfaff Date: Thu, 28 Sep 2006 12:59:05 +0000 Subject: [PATCH] Minor doc improvements. From Godmar Back. --- doc/userprog.texi | 5 ----- doc/vm.texi | 6 +++--- 2 files changed, 3 insertions(+), 8 deletions(-) diff --git a/doc/userprog.texi b/doc/userprog.texi index bb05dfb..11d9875 100644 --- a/doc/userprog.texi +++ b/doc/userprog.texi @@ -314,11 +314,6 @@ the running process. However, even in the kernel, an attempt to access memory at an unmapped user virtual address will cause a page fault. -You must handle memory fragmentation gracefully, that is, a process that -needs @var{N} pages of user virtual memory must not require those pages -to be contiguous in physical memory (or, equivalently, in kernel virtual -memory). - @menu * Typical Memory Layout:: @end menu diff --git a/doc/vm.texi b/doc/vm.texi index be99808..2376aa1 100644 --- a/doc/vm.texi +++ b/doc/vm.texi @@ -73,7 +73,7 @@ memory and storage. Some of these terms should be familiar from project @node Pages @subsubsection Pages -A @dfn{page}, sometimes called a @dfn{virtual page}, is a contiguous +A @dfn{page}, sometimes called a @dfn{virtual page}, is a continuous region of virtual memory 4,096 bytes (the @dfn{page size}) in length. A page must be @dfn{page-aligned}, that is, start on a virtual address evenly divisible by the page size. Thus, a 32-bit virtual address can @@ -105,7 +105,7 @@ addresses. @xref{Virtual Addresses}, for details. @subsubsection Frames A @dfn{frame}, sometimes called a @dfn{physical frame} or a @dfn{page -frame}, is a contiguous region of physical memory. Like pages, frames +frame}, is a continuous region of physical memory. Like pages, frames must be page-size and page-aligned. Thus, a 32-bit physical address can be divided into a 20-bit @dfn{frame number} and a 12-bit @dfn{frame offset} (or just @dfn{offset}), like this: @@ -162,7 +162,7 @@ address, on the right. @node Swap Slots @subsubsection Swap Slots -A @dfn{swap slot} is a contiguous, page-size region of disk space on the +A @dfn{swap slot} is a continuous, page-size region of disk space on the swap disk. Although hardware limitations dictating the placement of slots are looser than for pages and frames, swap slots should be page-aligned because there is no downside in doing so. -- 2.30.2