Commit graph

169 commits

Author SHA1 Message Date
Ben Gras
b6ea15115c kernel: facility for user-visible memory
. map all objects named usermapped_*.o with globally visible
	  pages; usermapped_glo_*.o with the VM 'global' bit on, i.e.
	  permanently in tlb (very scarce resource!)
	. added kinfo, machine, kmessages and loadinfo for a start
	. modified log, tty to make use of the shared messages struct
2012-07-28 20:57:38 +00:00
Ben Gras
cbcdb838f1 various coverity-inspired fixes
. some strncpy/strcpy to strlcpy conversions
	. new <minix/param.h> to avoid including other minix headers
	  that have colliding definitions with library and commands code,
	  causing parse warnings
	. removed some dead code / assignments
2012-07-16 14:00:56 +02:00
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
Thomas Veerman
f09c2e014f Use MACHINE_ARCH instead of ARCH 2012-06-18 10:53:35 +00:00
Thomas Veerman
f93afa00e9 Remove MINIXSRCDIR and use NETBSDSRCDIR
NETBSDSRCDIR is used all over the place anyway, and this reduces
our diff with NetBSD a little.
2012-06-18 10:53:35 +00:00
Ben Gras
2bfeeed885 drop segment from safecopy invocations
. all invocations were S or D, so can safely be dropped
	  to prepare for the segmentless world
	. still assign D to the SCP_SEG field in the message
	  to make previous kernels usable
2012-06-16 16:22:51 +00:00
Ben Gras
769af57274 further libexec generalization
. new mode for sys_memset: include process so memset can be
	  done in physical or virtual address space.
	. add a mode to mmap() that lets a process allocate uninitialized
	  memory.
	. this allows an exec()er (RS, VFS, etc.) to request uninitialized
	  memory from VM and selectively clear the ranges that don't come
	  from a file, leaving no uninitialized memory left for the process
	  to see.
	. use callbacks for clearing the process, clearing memory in the
	  process, and copying into the process; so that the libexec code
	  can be used from rs, vfs, and in the future, kernel (to load vm)
	  and vm (to load boot-time processes)
2012-06-07 15:15:02 +02:00
Ben Gras
040362e379 exec() cleanup, generalization, improvement
. make exec() callers (i.e. vfs and rs) determine the
	  memory layout by explicitly reserving regions using
	  mmap() calls on behalf of the exec()ing process,
	  i.e. handling all of the exec logic, thereby eliminating
	  all special exec() knowledge from VM.
	. the new procedure is: clear the exec()ing process
	  first, then call third-party mmap()s to reserve memory, then
	  copy the executable file section contents in, all using callbacks
	  tailored to the caller's way of starting an executable
	. i.e. no more explicit EXEC_NEWMEM-style calls in PM or VM
	  as with rigid 2-section arguments
	. this naturally allows generalizing exec() by simply loading
	  all ELF sections
	. drop/merge of lots of duplicate exec() code into libexec
	. not copying the code sections to vfs and into the executable
	  again is a measurable performance improvement (about 3.3% faster
	  for 'make' in src/servers/)
2012-06-07 15:15:01 +02:00
Ben Gras
ee4016155e vm: add third-party mmap() mode and PROCCTL
these two functions will be used to support all exec() functionality
going into a single library shared by RS and VFS and exec() knowledge
leaving VM.

	. third-party mmap: allow certain processes (VFS, RS) to
	  do mmap() on behalf of another process
	. PROCCTL: used to free and clear a process' address space
2012-06-07 12:43:16 +02:00
Ben Gras
99866db8cd vm: add MAP_FIXED 2012-04-12 15:01:36 +02:00
Ben Gras
b480472a76 vm: full memory view
for user-space processes, increase text segment so it reaches the full
address space, so code can be executed anywhere.
2012-04-12 02:58:39 +02:00
Ben Gras
660e15b2d1 vm: break: allow brk() on any region
use the user-supplied point to lookup which region to perform brk() on,
and if it's a reasonable one, do it, no matter what vm's notion of the
heap region is.
2012-04-12 02:57:59 +02:00
Ben Gras
7336a67dfe retire PUBLIC, PRIVATE and FORWARD 2012-03-25 21:58:14 +02:00
Ben Gras
6a73e85ad1 retire _PROTOTYPE
. only good for obsolete K&R support
	. also remove a stray ansi.h and the proto cmd
2012-03-25 16:17:10 +02:00
David van Moolenbroek
b91295a8d2 vm: if mmap address is given, try that first
Previously, the mmap address (if given) was merely used as a lower
bound, and then possibly overriden with a hint. Now, the mapping is
first tried at the exact given address. If that fails, the start of
the mmap range is used as lower bound (which is then still overridden
by the hint for efficiency).

This allows two pages to be mapped in at predefined addresses, where
the second address is lower than the first. That was not possible.
2012-03-24 19:51:14 +01:00
Ben Gras
6af9856d4a libcompat_minix-centric cleanup
remove some old minix-userland-specific stuff

	. /etc/ttytab as a file, and minix-compat function (fftyslot()),
	  replaced by /etc/ttys and new libc functions
	. also remove minix-specific nlist(), cuserid(), fttyslot(), v8 regex
	  functions and <compat/regex.h>
	. and remaining minix-only utilities that use them
	. also unused <compat/pwd.h> and <compat/syslog.h> and
	  redundant <sys/sigcontext.h>
2012-03-16 17:06:24 +01:00
Arun Thomas
5d958f894f servers: fix clang warnings in iso9660fs and vm 2012-02-17 16:48:40 +01:00
Arun Thomas
ff56906879 Remove obsolete INSTALLFLAGS from makefiles 2012-02-16 23:26:38 +01:00
Antoine Leca
3fb8cb760c More cleaning up 2012-02-15 19:04:58 +00:00
David van Moolenbroek
2c685f34e0 Cut PM out of the adddma/deldma/getdma call path 2012-01-14 00:27:06 +01:00
Ben Gras
4668b84158 vm_remap_ro
- allows shared memory to be mapped in readonly

- ben@minix3.org & tom@minix3.org
2012-01-13 11:30:01 +00:00
Tomas Hruby
88f990e122 VM - vm_unmap() takes SELF as valid argument 2012-01-13 11:30:01 +00:00
Tomas Hruby
974452d4dd VM - clear vminhibit iff it was set 2012-01-13 11:30:01 +00:00
Ben Gras
7cd4002083 vm: clear map cache after kernel requests
. fixes a dirty tlb situation (i.e. random crashes)
	  on some hardware, seemingly new intel architectures
	  (e.g. my desktop i7 machine)
2012-01-11 01:15:35 +01:00
Ben Gras
ef99a7a3dc vm: report cropped region sizes
. when reporting on regions, only report part of the
	  region (addr and length) that really has memory mapped
	  into it
	. to minimise core files
2011-11-26 15:12:17 +00:00
Thomas Veerman
8c9e62b299 Revert to using flushtlb instead of invlpg
Somehow the usage of invlpg causes Minix to crash on Qemu. Reverting
temporarily until we have a proper fix.
2011-09-27 15:15:51 +00:00
Ben Gras
833183a9e1 vm: undo accidental JUNKFREE on 2011-09-19 15:36:46 +00:00
Ben Gras
1dfd43ac27 boot e820 memory detection fixes 2011-09-19 13:36:03 +00:00
Thomas Veerman
d4b72e81b2 Cleanup servers to make GCC/Clang a little happier 2011-09-08 13:57:03 +00:00
Ben Gras
35cc7fbeb8 kernel: invlpg facility
. only use for single-page invalidations initially
	. shows tiny but statistically significant performance
	  improvement; will be more helpful in certain VM debug
	  modes
2011-08-12 13:08:27 +00:00
Ben Gras
d477a9ed82 vm/ipc: only report signals when it matters to ipc
. ipc wants to know about processes that get
	  signals, so that it can break blocking ipc operations
	. doing it for every single signal is wasteful
	  and causes the annoying 'no slot for signals' message
	. this fix tells vm on a per-process basis it (ipc)
	  wants to be notified, i.e. only when it does any ipc calls
	. move ipc config to separate config file while we're at it
2011-08-05 20:52:32 +00:00
Erik van der Kouwe
b1408f61b4 Sanity checks prevent VM panic for mmap, vm_remap and map_phys 2011-07-19 08:58:01 +02:00
Ben Gras
832f7f99fd vm: munmap fix leftover 2011-07-18 12:03:58 +02:00
Ben Gras
85f6d866e6 rename mmap MAP_SHARED to MAP_IPC_SHARED
. MAP_SHARED was used to implement sysv shared memory
	. used to signal shareable memory region to VM
	. assumptions about this situation break when processes
	  use MAP_SHARED for its normal, standardised meaning
2011-07-15 18:10:50 +02:00
Evgeniy Ivanov
ef0a265086 New stat structure.
* VFS and installed MFSes must be in sync before and after this change *

Use struct stat from NetBSD. It requires adding new STAT, FSTAT and LSTAT
syscalls. Libc modification is both backward and forward compatible.

Also new struct stat uses modern field sizes to avoid ABI
incompatibility, when we update uid_t, gid_t and company.
Exceptions are ino_t and off_t in old libc (though paddings added).
2011-07-12 16:39:55 +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
c2da8cb535 Globally enable -Wall warnings for GCC 2011-06-08 19:21:03 +00:00
Erik van der Kouwe
0cb22acbda Fix VM -Wall warnings and enable -Werror 2011-06-01 11:30:58 +02:00
Arun Thomas
350b60661a ELF multiboot support 2011-05-04 18:51:43 +02:00
Ben Gras
5f1ab506c8 remove some debugging output from vm/region.c
- don't print verbose process map when legitimate errors occur
2011-03-16 11:57:35 +00:00
Arun Thomas
25a790a631 VM and kernel support for ELF 2011-02-26 23:00:55 +00:00
Ben Gras
c7b2b11ec2 vm: only suspend and resume process with vmctls in pt_writemap in smp mode 2011-02-11 14:56:52 +00:00
Arun Thomas
372b873413 VFS/RS support for ELF 2010-12-10 09:27:56 +00:00
Tomas Hruby
de1bcaa69a VM implicitly aligns mappings to a page
- problem when a PCI BAR is not aligned

- together with  David v. Moolenboek
2010-10-21 17:07:05 +00:00
Ben Gras
ddde360e3e vm - hash table for block cache 2010-10-15 09:10:14 +00:00
Ben Gras
cb2e3a98a2 vm - fix for not placing region outside requested mmap addr 2010-10-15 09:09:29 +00:00
Ben Gras
a3f2df124c vm optimisation - maintain hint for new virtual region position. 2010-10-07 10:04:05 +00:00
Ben Gras
e2570d9b1b vm: optimisation: avl tree for virtual regions
- regions were preivous stored in a linked list, as 'normally'
    there are just 2 or 3 (text, data, stack), but that's slow
    if lots of regions are made with mmap()

  - measurable performance improvement with gcc and clang
2010-10-04 11:41:10 +00:00
Ben Gras
36189370a5 vm: don't check the range of memory during sanity checking
- too many false positives due to memory that is mapped in
    legitimately (acpi, i/o devices)
2010-10-04 11:38:33 +00:00