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| -rw-r--r-- | microkernel/mach/gnumach.mdwn | 9 | ||||
| -rw-r--r-- | microkernel/mach/gnumach/memory_management.mdwn | 36 |
2 files changed, 41 insertions, 4 deletions
diff --git a/microkernel/mach/gnumach.mdwn b/microkernel/mach/gnumach.mdwn index f3d6d5f9..b385ca09 100644 --- a/microkernel/mach/gnumach.mdwn +++ b/microkernel/mach/gnumach.mdwn @@ -1,13 +1,13 @@ -[[!meta copyright="Copyright © 2001, 2002, 2007, 2008 Free Software Foundation, -Inc."]] +[[!meta copyright="Copyright © 2001, 2002, 2007, 2008, 2011 Free Software +Foundation, Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable id="license" text="Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license -is included in the section entitled -[[GNU Free Documentation License|/fdl]]."]]"""]] +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] GNU Mach is the microkernel that the [[GNU_Hurd|hurd]] system is based on. @@ -75,6 +75,7 @@ GNU/Hurd. * [[Building]] * [[Debugging]] * [[Boot_Trace]] + * [[Memory_Management]] * [[Projects]] * [[Rules]] * [[Open Issues|tag/open_issue_gnumach]] diff --git a/microkernel/mach/gnumach/memory_management.mdwn b/microkernel/mach/gnumach/memory_management.mdwn new file mode 100644 index 00000000..49a082e9 --- /dev/null +++ b/microkernel/mach/gnumach/memory_management.mdwn @@ -0,0 +1,36 @@ +[[!meta copyright="Copyright © 2011 Free Software Foundation, Inc."]] + +[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable +id="license" text="Permission is granted to copy, distribute and/or modify this +document under the terms of the GNU Free Documentation License, Version 1.2 or +any later version published by the Free Software Foundation; with no Invariant +Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] + +IRC, freenode, #hurd, 2011-02-15 + + <braunr> etenil: originally, mach had its own virtual space (the kernel + space) + <braunr> etenil: in order to use linux 2.0 drivers, it now directly maps + physical memory, as linux does + <braunr> etenil: but there is nothing similar to kmap() or vmalloc() in + mach, so the kernel is limited to its 1 GiB + <braunr> (3 GiB userspace / 1 GiB kernelspace) + <braunr> that's the short version, there is a vmalloc() in mach, but this + trick made it behave almost like a kmalloc() + <antrik> braunr: the direct mapping is *only* for the benefit of Linux + drivers?... + <braunr> also, the configuration of segments limits the kernel space + <braunr> antrik: i'm not sure, as i said, this is the short version + <braunr> antrik: but there is a paper which describes the integration of + those drivers in mach + <etenil> you mean the linux 2.0 drivers? + <antrik> braunr: I read it once, but I don't remember anything about the + physical mapping in there... + <antrik> etenil: well, originally it was 1.3, but essentially that's the + same... + <braunr> i don't see any other reason why there would be a direct mapping + <braunr> except for performance (because you can use larger - even very + lage - pages without resetting the mmu often thanks to global pages, but + that didn't exist at the time) |