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18 commits

Author SHA1 Message Date
David van Moolenbroek
78d707cd26 VM: support for shared call mask ACLs
The VM server now manages its call masks such that all user processes
share the same call mask. As a result, an update for the call mask of
any user process will apply to all user processes. This is similar to
the privilege infrastructure employed by the kernel, and may serve as
a template for similar fine-grained restrictions in other servers.

Concretely, this patch fixes the problem of "service edit init" not
applying the given VM call mask to user processes started from RC
scripts during system startup.

In addition, this patch makes RS set a proper VM call mask for each
recovery script it spawns.

Change-Id: I520a30d85a0d3f3502d2b158293a2258825358cf
2013-08-08 23:22:58 +02:00
Xiaoguang Sun
64f10ee644 Implement getrusage
Implement getrusage.
These fields of struct rusage are not supported and always set to zero at this time
long ru_nswap;           /* swaps */
long ru_inblock;         /* block input operations */
long ru_oublock;         /* block output operations */
long ru_msgsnd;          /* messages sent */
long ru_msgrcv;          /* messages received */
long ru_nvcsw;           /* voluntary context switches */
long ru_nivcsw;          /* involuntary context switches */

test75.c is the unit test for this new function

Change-Id: I3f1eb69de1fce90d087d76773b09021fc6106539
2013-07-01 23:00:47 +02:00
Ben Gras
49eb1f4806 vm: new secondary cache code
Primary purpose of change: to support the mmap implementation, VM must
know both (a) about some block metadata for FS cache blocks, i.e.
inode numbers and inode offsets where applicable; and (b) know about
*all* cache blocks, i.e.  also of the FS primary caches and not just
the blocks that spill into the secondary one. This changes the
interface and VM data structures.

This change is only for the interface (libminixfs) and VM data
structures; the filesystem code is unmodified, so although the
secondary cache will be used as normal, blocks will not be annotated
with inode information until the FS is modified to provide this
information. Until it is modified, mmap of files will fail gracefully
on such filesystems.

This is indicated to VFS/VM by returning ENOSYS for REQ_PEEK.

Change-Id: I1d2df6c485e6c5e89eb28d9055076cc02629594e
2013-04-24 10:18:16 +00:00
Ben Gras
adf2032bc0 vm: remove secondary cache code
This commit removes the secondary cache code implementation from
VM and its usage from libminixfs. It is to be replaced by a new
implementation.

Change-Id: I8fa3af06330e7604c7e0dd4cbe39d3ce353a05b1
2013-04-24 10:18:10 +00:00
Ben Gras
29edcad310 vm: replace phys avl by array
. make vm be able to use malloc() by overriding brk()
   and minix_mmap() functions
 . phys regions can then be malloc()ed and free()d instead
   of being in an avl tree, which is slightly faster
 . 'offset' field in phys_region can go too (offset is implied
   by position in array) but leads to bigger code changes
2012-12-26 16:14:41 +00:00
Ben Gras
3771a0833d vm: merge i386 and arm pagetable code 2012-11-09 18:46:03 +01:00
Ben Gras
2cb560297c VM: remove unused dma memory support functions from vm
. unused calls / data structures
2012-09-18 13:17:47 +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
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
Ben Gras
ddde360e3e vm - hash table for block cache 2010-10-15 09:10:14 +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
f78d8e74fd secondary cache feature in vm.
A new call to vm lets processes yield a part of their memory to vm,
together with an id, getting newly allocated memory in return. vm is
allowed to forget about it if it runs out of memory. processes can ask
for it back using the same id. (These two operations are normally
combined in a single call.)

It can be used as a as-big-as-memory-will-allow block cache for
filesystems, which is how mfs now uses it.
2010-05-05 11:35:04 +00:00
Ben Gras
c78250332d let vm use physically fragmented memory for allocations.
map_copy_ph_block is replaced by map_clone_ph_block, which can
replace a single physical block by multiple physical blocks.

also,
 . merge map_mem.c with region.c, as they manipulate the same
   data structures
 . NOTRUNNABLE removed as sanity check
 . use direct functions for ALLOC_MEM and FREE_MEM again
 . add some checks to shared memory mapping code
 . fix for data structure integrity when using shared memory
 . fix sanity checks
2010-04-12 11:25:24 +00:00
Cristiano Giuffrida
d1fd04e72a Initialization protocol for system services.
SYSLIB CHANGES:
- SEF framework now supports a new SEF Init request type from RS. 3 different
callbacks are available (init_fresh, init_lu, init_restart) to specify
initialization code when a service starts fresh, starts after a live update,
or restarts.

SYSTEM SERVICE CHANGES:
- Initialization code for system services is now enclosed in a callback SEF will
automatically call at init time. The return code of the callback will
tell RS whether the initialization completed successfully.
- Each init callback can access information passed by RS to initialize. As of
now, each system service has access to the public entries of RS's system process
table to gather all the information required to initialize. This design
eliminates many existing or potential races at boot time and provides a uniform
initialization interface to system services. The same interface will be reused
for the upcoming publish/subscribe model to handle dynamic 
registration / deregistration of system services.

VM CHANGES:
- Uniform privilege management for all system services. Every service uses the
same call mask format. For boot services, VM copies the call mask from init
data. For dynamic services, VM still receives the call mask via rs_set_priv
call that will be soon replaced by the upcoming publish/subscribe model.

RS CHANGES:
- The system process table has been reorganized and split into private entries
and public entries. Only the latter ones are exposed to system services.
- VM call masks are now entirely configured in rs/table.c
- RS has now its own slot in the system process table. Only kernel tasks and
user processes not included in the boot image are now left out from the system
process table.
- RS implements the initialization protocol for system services.
- For services in the boot image, RS blocks till initialization is complete and
panics when failure is reported back. Services are initialized in their order of
appearance in the boot image priv table and RS blocks to implements synchronous
initialization for every system service having the flag SF_SYNCH_BOOT set.
- For services started dynamically, the initialization protocol is implemented
as though it were the first ping for the service. In this case, if the
system service fails to report back (or reports failure), RS brings the service
down rather than trying to restart it.
2010-01-08 01:20:42 +00:00
Ben Gras
32fbbd370c - pages that points to page directory values of all processes,
shared with the kernel, mapped into kernel address space; 
   kernel is notified of its location. kernel segment size is
   increased to make it fit.
 - map in kernel and other processes that don't have their
   own page table using single 4MB (global) mapping.
 - new sanity check facility: objects that are allocated with
   the slab allocator are, when running with sanity checking on,
   marked readonly until they are explicitly unlocked using the USE()
   macro.
 - another sanity check facility: collect all uses of memory and
   see if they don't overlap with (a) eachother and (b) free memory
 - own munmap() and munmap_text() functions.
 - exec() recovers from out-of-memory conditions properly now; this
   solves some weird exec() behaviour
 - chew off memory from the same side of the chunk as where we
   start scanning, solving some memory fragmentation issues
 - use avl trees for freelist and phys_ranges in regions
 - implement most useful part of munmap()
 - remap() stuff is GQ's for shared memory
2009-09-21 14:49:49 +00:00
Ben Gras
bdab3c4cfb Library call for cpu features; make kernel and vm use this to query cpu
features (specifically: 4MB pages and TLB global bit).  Only enable
these features in CR4 if available. 4MB pages to be used in the near
future.
2009-05-15 17:07:36 +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