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30 commits

Author SHA1 Message Date
Ben Gras
50e2064049 No more intel/minix segments.
This commit removes all traces of Minix segments (the text/data/stack
memory map abstraction in the kernel) and significance of Intel segments
(hardware segments like CS, DS that add offsets to all addressing before
page table translation). This ultimately simplifies the memory layout
and addressing and makes the same layout possible on non-Intel
architectures.

There are only two types of addresses in the world now: virtual
and physical; even the kernel and processes have the same virtual
address space. Kernel and user processes can be distinguished at a
glance as processes won't use 0xF0000000 and above.

No static pre-allocated memory sizes exist any more.

Changes to booting:
        . The pre_init.c leaves the kernel and modules exactly as
          they were left by the bootloader in physical memory
        . The kernel starts running using physical addressing,
          loaded at a fixed location given in its linker script by the
          bootloader.  All code and data in this phase are linked to
          this fixed low location.
        . It makes a bootstrap pagetable to map itself to a
          fixed high location (also in linker script) and jumps to
          the high address. All code and data then use this high addressing.
        . All code/data symbols linked at the low addresses is prefixed by
          an objcopy step with __k_unpaged_*, so that that code cannot
          reference highly-linked symbols (which aren't valid yet) or vice
          versa (symbols that aren't valid any more).
        . The two addressing modes are separated in the linker script by
          collecting the unpaged_*.o objects and linking them with low
          addresses, and linking the rest high. Some objects are linked
          twice, once low and once high.
        . The bootstrap phase passes a lot of information (e.g. free memory
          list, physical location of the modules, etc.) using the kinfo
          struct.
        . After this bootstrap the low-linked part is freed.
        . The kernel maps in VM into the bootstrap page table so that VM can
          begin executing. Its first job is to make page tables for all other
          boot processes. So VM runs before RS, and RS gets a fully dynamic,
          VM-managed address space. VM gets its privilege info from RS as usual
          but that happens after RS starts running.
        . Both the kernel loading VM and VM organizing boot processes happen
	  using the libexec logic. This removes the last reason for VM to
	  still know much about exec() and vm/exec.c is gone.

Further Implementation:
        . All segments are based at 0 and have a 4 GB limit.
        . The kernel is mapped in at the top of the virtual address
          space so as not to constrain the user processes.
        . Processes do not use segments from the LDT at all; there are
          no segments in the LDT any more, so no LLDT is needed.
        . The Minix segments T/D/S are gone and so none of the
          user-space or in-kernel copy functions use them. The copy
          functions use a process endpoint of NONE to realize it's
          a physical address, virtual otherwise.
        . The umap call only makes sense to translate a virtual address
          to a physical address now.
        . Segments-related calls like newmap and alloc_segments are gone.
        . All segments-related translation in VM is gone (vir2map etc).
        . Initialization in VM is simpler as no moving around is necessary.
        . VM and all other boot processes can be linked wherever they wish
          and will be mapped in at the right location by the kernel and VM
          respectively.

Other changes:
        . The multiboot code is less special: it does not use mb_print
          for its diagnostics any more but uses printf() as normal, saving
          the output into the diagnostics buffer, only printing to the
          screen using the direct print functions if a panic() occurs.
        . The multiboot code uses the flexible 'free memory map list'
          style to receive the list of free memory if available.
        . The kernel determines the memory layout of the processes to
          a degree: it tells VM where the kernel starts and ends and
          where the kernel wants the top of the process to be. VM then
          uses this entire range, i.e. the stack is right at the top,
          and mmap()ped bits of memory are placed below that downwards,
          and the break grows upwards.

Other Consequences:
        . Every process gets its own page table as address spaces
          can't be separated any more by segments.
        . As all segments are 0-based, there is no distinction between
          virtual and linear addresses, nor between userspace and
          kernel addresses.
        . Less work is done when context switching, leading to a net
          performance increase. (8% faster on my machine for 'make servers'.)
	. The layout and configuration of the GDT makes sysenter and syscall
	  possible.
2012-07-15 22:30:15 +02:00
Arun Thomas
ff56906879 Remove obsolete INSTALLFLAGS from makefiles 2012-02-16 23:26:38 +01:00
Ben Gras
2fe8fb192f Full switch to clang/ELF. Drop ack. Simplify.
There is important information about booting non-ack images in
docs/UPDATING. ack/aout-format images can't be built any more, and
booting clang/ELF-format ones is a little different. Updating to the
new boot monitor is recommended.

Changes in this commit:

	. drop boot monitor -> allowing dropping ack support
	. facility to copy ELF boot files to /boot so that old boot monitor
	  can still boot fairly easily, see UPDATING
	. no more ack-format libraries -> single-case libraries
	. some cleanup of OBJECT_FMT, COMPILER_TYPE, etc cases
	. drop several ack toolchain commands, but not all support
	  commands (e.g. aal is gone but acksize is not yet).
	. a few libc files moved to netbsd libc dir
	. new /bin/date as minix date used code in libc/
	. test compile fix
	. harmonize includes
	. /usr/lib is no longer special: without ack, /usr/lib plays no
	  kind of special bootstrapping role any more and bootstrapping
	  is done exclusively through packages, so releases depend even
	  less on the state of the machine making them now.
	. rename nbsd_lib* to lib*
	. reduce mtree
2012-02-14 14:52:02 +01:00
David van Moolenbroek
01015cc0e2 init: write boot entry to root wtmp
This unbreaks the fsck check on startup.
2011-12-05 13:56:16 +01:00
Thomas Veerman
d4b72e81b2 Cleanup servers to make GCC/Clang a little happier 2011-09-08 13:57:03 +00:00
Arun Thomas
b956c8735e Fix GCC image building 2011-07-09 15:04:42 +02:00
Arun Thomas
93ae43f577 boot: Add multiboot support
Not yet fully spec-compliant; work in progress
2011-06-24 17:21:51 +02:00
Gianluca Guida
cc17b27a2b Build NetBSD libc library in world in ELF mode.
3 sets of libraries are built now:
  . ack: all libraries that ack can compile (/usr/lib/i386/)
  . clang+elf: all libraries with minix headers (/usr/lib/)
  . clang+elf: all libraries with netbsd headers (/usr/netbsd/)

Once everything can be compiled with netbsd libraries and headers, the
/usr/netbsd hierarchy will be obsolete and its libraries compiled with
netbsd headers will be installed in /usr/lib, and its headers
in /usr/include. (i.e. minix libc and current minix headers set
will be gone.)

To use the NetBSD libc system (libraries + headers) before
it is the default libc, see:
   http://wiki.minix3.org/en/DevelopersGuide/UsingNetBSDCode
This wiki page also documents the maintenance of the patch
files of minix-specific changes to imported NetBSD code.

Changes in this commit:
  . libsys: Add NBSD compilation and create a safe NBSD-based libc.
  . Port rest of libraries (except libddekit) to new header system.
  . Enable compilation of libddekit with new headers.
  . Enable kernel compilation with new headers.
  . Enable drivers compilation with new headers.
  . Port legacy commands to new headers and libc.
  . Port servers to new headers.
  . Add <sys/sigcontext.h> in compat library.
  . Remove dependency file in tree.
  . Enable compilation of common/lib/libc/atomic in libsys
  . Do not generate RCSID strings in libc.
  . Temporarily disable zoneinfo as they are incompatible with NetBSD format
  . obj-nbsd for .gitignore
  . Procfs: use only integer arithmetic. (Antoine Leca)
  . Increase ramdisk size to create NBSD-based images.
  . Remove INCSYMLINKS handling hack.
  . Add nbsd_include/sys/exec_elf.h
  . Enable ELF compilation with NBSD libc.
  . Add 'make nbsdsrc' in tools to download reference NetBSD sources.
  . Automate minix-port.patch creation.
  . Avoid using fstavfs() as it is *extremely* slow and unneeded.
  . Set err() as PRIVATE to avoid name clash with libc.
  . [NBSD] servers/vm: remove compilation warnings.
  . u32 is not a long in NBSD headers.
  . UPDATING info on netbsd hierarchy
  . commands fixes for netbsd libc
2011-06-24 11:46:30 +02:00
Erik van der Kouwe
1f2054c89c Shutdown changes for multiboot: CTRL-ALT-DEL resets, panic halts 2010-08-30 19:01:58 +00:00
Arun Thomas
c0c8d25799 Rename mkfiles from minix.*.mk to bsd.*.mk
Makes things easier for pkgsrc
2010-06-25 18:29:09 +00:00
Arun Thomas
1b2c01db1b Makefile updates:
Turn on optimization
Remove some redundancy in FLAGS
2010-06-11 16:05:36 +00:00
Arun Thomas
f0a158d8c1 More cleanup to remove MM and FS references 2010-06-10 14:04:46 +00:00
Arun Thomas
007104d60e GCC build fixes/updates
-Set stack sizes for boot image processes
-Increase RS stack size
-Reduce ramdisk size
-HARDWARE task should use kernel stack
-Minor asm tweaks for leading underscores
2010-05-26 18:45:55 +00:00
Erik van der Kouwe
1f11a57141 Oops, last commit included more than was intended 2010-05-20 08:07:47 +00:00
Erik van der Kouwe
5f15ec05b2 More system processes, this was not enough for the release script to run on some configurations 2010-05-20 08:05:07 +00:00
Arun Thomas
436d6012a3 Convert drivers/ and servers/ over to bsdmake
-Move libdriver to lib/
-Install all boot image services on filesystem to aid restartability
2010-03-22 21:25:22 +00:00
Arun Thomas
b706112487 Incorporate bsdmake into buildsystem and reorganize libs 2010-02-16 14:41:33 +00:00
Kees van Reeuwijk
5459f3a607 Removed a whole herd of unused variables.
Some other cleanup.
2010-01-14 13:53:12 +00:00
Cristiano Giuffrida
f4574783dc Rewrite of boot process
KERNEL CHANGES:
- The kernel only knows about privileges of kernel tasks and the root system
process (now RS).
- Kernel tasks and the root system process are the only processes that are made
schedulable by the kernel at startup. All the other processes in the boot image
don't get their privileges set at startup and are inhibited from running by the
RTS_NO_PRIV flag.
- Removed the assumption on the ordering of processes in the boot image table.
System processes can now appear in any order in the boot image table.
- Privilege ids can now be assigned both statically or dynamically. The kernel
assigns static privilege ids to kernel tasks and the root system process. Each
id is directly derived from the process number.
- User processes now all share the static privilege id of the root user
process (now INIT).
- sys_privctl split: we have more calls now to let RS set privileges for system
processes. SYS_PRIV_ALLOW / SYS_PRIV_DISALLOW are only used to flip the
RTS_NO_PRIV flag and allow / disallow a process from running. SYS_PRIV_SET_SYS /
SYS_PRIV_SET_USER are used to set privileges for a system / user process.
- boot image table flags split: PROC_FULLVM is the only flag that has been
moved out of the privilege flags and is still maintained in the boot image
table. All the other privilege flags are out of the kernel now.

RS CHANGES:
- RS is the only user-space process who gets to run right after in-kernel
startup.
- RS uses the boot image table from the kernel and three additional boot image
info table (priv table, sys table, dev table) to complete the initialization
of the system.
- RS checks that the entries in the priv table match the entries in the boot
image table to make sure that every process in the boot image gets schedulable.
- RS only uses static privilege ids to set privileges for system services in
the boot image.
- RS includes basic memory management support to allocate the boot image buffer
dynamically during initialization. The buffer shall contain the executable
image of all the system services we would like to restart after a crash.
- First step towards decoupling between resource provisioning and resource
requirements in RS: RS must know what resources it needs to restart a process
and what resources it has currently available. This is useful to tradeoff
reliability and resource consumption. When required resources are missing, the
process cannot be restarted. In that case, in the future, a system flag will
tell RS what to do. For example, if CORE_PROC is set, RS should trigger a
system-wide panic because the system can no longer function correctly without
a core system process.

PM CHANGES:
- The process tree built at initialization time is changed to have INIT as root
with pid 0, RS child of INIT and all the system services children of RS. This
is required to make RS in control of all the system services.
- PM no longer registers labels for system services in the boot image. This is
now part of RS's initialization process.
2009-12-11 00:08:19 +00:00
Ben Gras
b696823379 stingy stack. 2009-02-06 16:29:00 +00:00
Ben Gras
e9f0c576a3 Open stdin, stdout and stderr only after /etc/rc has executed. (/etc/rc
executes it itself.) This avoids keeping /dev nodes on the temporary
root filesystem (initial mfs) in use unnecessarily.
2008-12-11 14:43:25 +00:00
Ben Gras
c078ec0331 Basic VM and other minor improvements.
Not complete, probably not fully debugged or optimized.
2008-11-19 12:26:10 +00:00
Ben Gras
9f2f3dd488 don't call mkdep with an absolute path 2007-02-08 16:26:20 +00:00
Philip Homburg
14b7a72ba3 Init need more space (the results of removing the special case for init in
adjust in PM). Better flags dump in IS.
2006-05-11 15:00:46 +00:00
Ben Gras
d11b2e4b8c Al's double-blank-line removal request 2005-08-22 15:23:47 +00:00
Jorrit Herder
5594b767c0 Renamed src/lib/utils to src/lib/sysutil --- because of new src/lib/util 2005-07-19 13:21:51 +00:00
Jorrit Herder
f2e16763e7 Removed PM signon for INET. Now daemonized in /usr/etc/rc.
SIGTRAP generated in PM (where it belongs / no longer in kernel).
Updated Makefiles: servers are now installed in /usr/sbin.
2005-07-19 12:11:11 +00:00
Jorrit Herder
042c4ac395 Changed Makefiles for mkdep script.
Updated debugging dumps at IS server, and function key control.

NOTE: pm modified with DEBUG() output, to be removed later.
2005-06-24 16:21:21 +00:00
Jorrit Herder
f2a85e58d9 Various updates.
* Removed some variants of the SYS_GETINFO calls from the kernel;
  replaced them with new PM and utils libary functionality. Fixed
  bugs in utils library that used old get_kenv() variant.
* Implemented a buffer in the kernel to gather random data.
  Memory driver periodically checks this for /dev/random.
  A better random algorithm can now be implemented in the driver.
  Removed SYS_RANDOM; the SYS_GETINFO call is used instead.
* Remove SYS_KMALLOC from the kernel. Memory allocation can now
  be done at the process manager with new 'other' library functions.
2005-06-03 13:55:06 +00:00
Ben Gras
9865aeaa79 Initial revision 2005-04-21 14:53:53 +00:00