Commit Graph

85 Commits

Author SHA1 Message Date
Ingo Weinhold
7bf85edf58 Allow disabling ASLR via DISABLE_ASLR environment variable
* VMAddressSpace: Add randomizingEnabled property.
* VMUserAddressSpace: Randomize addresses only when randomizingEnabled
  property is set.
* create_team_arg(): Check, if the team's environment contains
  "DISABLE_ASLR=1". Set the team's address space property
  randomizingEnabled accordingly in load_image_internal() and
  exec_team().
2013-12-01 02:51:50 +01:00
Ingo Weinhold
e5f6591382 VM: vm_memset_physical(): Correct length parameter type 2013-11-11 22:27:52 +01:00
Pawel Dziepak
8614737f71 elf: restore correct region protection after relocation 2013-04-16 03:44:38 +02:00
Pawel Dziepak
966f207668 x86: enable data execution prevention
Set execute disable bit for any page that belongs to area with neither
B_EXECUTE_AREA nor B_KERNEL_EXECUTE_AREA set.

In order to take advanage of NX bit in 32 bit protected mode PAE must be
enabled. Thus, from now on it is also enabled when the CPU supports NX bit.

vm_page_fault() takes additional argument which indicates whether page fault
was caused by an illegal instruction fetch.
2013-04-04 15:22:23 +02:00
Hamish Morrison
d1f280c805 Add support for pthread_attr_get/setguardsize()
* Added the aforementioned functions.
* create_area_etc() now takes a guard size parameter.
* The thread_info::stack_base/end range now refers to the usable range
  only.
2012-12-28 18:02:58 +00:00
Alex Smith
6e2f6d1ace Changed cookie type for get_next_area_info() to ssize_t.
The cookie is used to store the base address of the area that was just
visited. On 64-bit systems, int32 is not sufficient. Therefore, changed
to ssize_t which retains compatibility on x86 while expanding to a
sufficient size on x86_64.
2012-07-29 09:31:14 +01:00
Michael Lotz
7418dbd908 Introduce debug page wise kernel area protection functions.
This adds a pair of functions vm_prepare_kernel_area_debug_protection()
and vm_set_kernel_area_debug_protection() to set a kernel area up for
page wise protection and to actually protect individual pages
respectively.

It was already possible to read and write protect full areas via area
protection flags and not mapping any actual pages. For areas that
actually have mapped pages this doesn't work however as no fault, at
which the permissions could be checked, is generated on access.

These new functions use the debug helpers of the translation map to mark
individual pages as non-present without unmapping them. This allows them
to be "protected", i.e. causing a fault on read and write access. As they
aren't actually unmapped they can later be marked present again.

Note that these are debug helpers and have quite a few restrictions as
described in the comment above the function and is only useful for some
very specific and constrained use cases.
2011-12-03 19:49:18 +01:00
Michael Lotz
643cf35ee8 Add debug helper functions to mark pages present.
They can be used to mark pages as present/non-present without actually
unmapping them. Marking pages as non-present causes every access to
fault. We can use that for debugging as it allows us to "read protect"
individual kernel pages.
2011-12-03 19:45:31 +01:00
Michael Lotz
2cdd33d4ff Add an assert to ensure the wired count doesn't wrap. 2011-11-13 22:02:36 +01:00
Michael Lotz
90c6930ebb Add VM page allocation tracking similar to what happens in the slab already.
Introduces "page_allocation_infos" and "page_allocations_per_caller" KDL
commands.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@43190 a95241bf-73f2-0310-859d-f6bbb57e9c96
2011-11-04 18:07:07 +00:00
Ingo Weinhold
f8154d172d mmlr (distracted) + bonefish:
* Turn VMCache::consumers C list into a DoublyLinkedList.
* Use object caches for the different VMCache types and the VMCacheRefs.
  The purpose is to reduce slab area fragmentation.
* Requires the introduction of a pure virtual VMCache::DeleteObject()
  method, implemented in the derived classes.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@43133 a95241bf-73f2-0310-859d-f6bbb57e9c96
2011-11-02 21:14:11 +00:00
Rene Gollent
e8d73efc9c Should have been part of previous commit.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@42130 a95241bf-73f2-0310-859d-f6bbb57e9c96
2011-06-12 20:18:01 +00:00
Ingo Weinhold
4535495d80 Merged the signals branch into trunk, with these changes:
* The team and thread kernel structures have been renamed to Team and Thread
  respectively and moved into the new BKernel namespace.
* Several (kernel add-on) sources have been converted from C to C++ since
  private kernel headers are included that are no longer C compatible.

Changes after merging:
* Fixed gcc 2 build (warnings mainly in the scary firewire bus manager).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40196 a95241bf-73f2-0310-859d-f6bbb57e9c96
2011-01-10 21:54:38 +00:00
Ingo Weinhold
a0d93d1416 * VMCache::Unlock(): Renamed local variable consumerLocked to avoid shadowing
the parameter (CID 5329).
* _MergeWithOnlyConsumer(): Removed the somewhat weird consumerLocked
  parameter. The caller can unlock itself, if desired. Improves Unlock()
  readability.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40084 a95241bf-73f2-0310-859d-f6bbb57e9c96
2011-01-03 00:44:40 +00:00
Ingo Weinhold
b944766870 * Moved the vm_page initialization from vm_page.cpp:vm_page_init() to the new
vm_page::Init().
* Made vm_page::wired_count private and added accessor methods.
* Added VMCache::fWiredPagesCount (the number of wired pages the cache
  contains) and accessor methods.
* Made more use of vm_page::IsMapped().
* vm_copy_on_write_area(): Added vm_page_reservation* parameter that can be
  used to request a special handling for wired pages. If given the wired pages
  are replaced by copies and the original pages are moved to the upper cache.
* vm_copy_area():
  - We don't need to do any wired ranges handling, if the source area is a
    B_SHARED_AREA, since we don't touch the area's mappings in this case.
  - We no longer wait for wired ranges of the concerned areas to disappear.
    Instead we use the new vm_copy_on_write_area() feature and just let it
    copy the wired pages. This fixes #6288, an issue introduced with the use
    of user mutexes in libroot: When executing multiple concurrent fork()s all
    but the first one would wait on the fork mutex, which (being a user mutex)
    would wire a page that the vm_copy_area() of the first fork() would wait
    for.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37460 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-07-10 15:08:13 +00:00
Fredrik Holmqvist
e5dca54f1a r37259 fails to compile on one of my systems without this header. Checking out fresh tree and reconfiguring didn't work so don't really know why.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37263 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-06-26 17:24:11 +00:00
Ingo Weinhold
b46540452a Added vm_page_max_address() which returns the greatest address of accessible
physical memory.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37230 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-06-23 13:52:32 +00:00
Ingo Weinhold
13638944db Removed never read VMCache::scan_skip.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37195 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-06-21 15:10:37 +00:00
Ingo Weinhold
0d5ab7a14d Moved duplicate code from the VMTranslationMap subclasses' UnmapPage() and
ClearAccessedAndModified() implementations into helper methods PageUnmapped()
and UnaccessedPageUnmapped() in the base class.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37187 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-06-21 13:32:33 +00:00
Ingo Weinhold
c955359cb6 Added vm_available_not_needed_memory_debug(), a
vm_available_not_needed_memory() version that can be called from within the
kernel debugger.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37167 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-06-18 20:57:05 +00:00
Ingo Weinhold
f8e263c184 Slipped by in r37138: Added VMCache::Dump() and removed GetLock().
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37141 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-06-15 00:07:18 +00:00
Ingo Weinhold
377ecfe797 * Renamed cache_type_to_string() to vm_cache_type_to_string() and made in
kernel private.
* Moved dumping code from dump_cache() to new VMCache::Dump().
* Override VMCache::Dump() in VMVnodeCache to also print the vnode.
* Removed no longer needed VMCache::GetLock().


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37138 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-06-14 23:57:00 +00:00
Ingo Weinhold
a8ad734f1c * Introduced structures {virtual,physical}_address_restrictions, which specify
restrictions for virtual/physical addresses.
* vm_page_allocate_page_run():
  - Fixed conversion of base/limit to array indexes. sPhysicalPageOffset was not
    taken into account.
  - Takes a physical_address_restrictions instead of base/limit and also
    supports alignment and boundary restrictions, now.
* map_backing_store(), VM[User,Kernel]AddressSpace::InsertArea()/
  ReserveAddressRange() take a virtual_address_restrictions parameter, now. They
  also support an alignment independent from the range size.
* create_area_etc(), vm_create_anonymous_area(): Take
  {virtual,physical}_address_restrictions parameters, now.
* Removed no longer needed B_PHYSICAL_BASE_ADDRESS.
* DMAResources:
  - Fixed potential overflows of uint32 when initializing from device node
    attributes.
  - Fixed bounce buffer creation TODOs: By using create_area_etc() with the
    new restrictions parameters we can directly support physical high address,
    boundary, and alignment.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37131 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-06-14 16:25:14 +00:00
Ingo Weinhold
1d26c7248f vm_page_allocate_page_run(): Added parameter "limit", specifying the upper
physical address limit for the page run to allocate.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37086 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-06-10 17:30:49 +00:00
Ingo Weinhold
641b3c82df Renamed allocate_early_physical_page() to vm_allocate_early_physical_page()
and made it public.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37072 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-06-09 21:21:18 +00:00
Ingo Weinhold
2ea7b17cf3 * vm_allocate_early(): Replace "bool blockAlign" parameter by a more flexible
"addr_t aligmnent".
* X86PagingMethod32Bit::PhysicalPageSlotPool::InitInitial(),
  generic_vm_physical_page_mapper_init(): Use vm_allocate_early()'s alignment
  feature instead of aligning by hand.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37070 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-06-09 11:15:43 +00:00
Ingo Weinhold
1ba89e67ed Removed no-op VMTranslationMap::InitPostSem() and
VMAddressSpace::InitPostSem().


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37025 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-06-05 22:20:34 +00:00
Ingo Weinhold
435c43f591 * Introduced type generic_io_vec, which is similar to iovec, but uses types
that are wide enough for both virtual and physical addresses.
* DMABuffer, IORequest, IOScheduler,... and code using them: Use
  generic_io_vec and generic_{addr,size}_t where necessary.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36997 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-06-02 18:42:20 +00:00
Ingo Weinhold
147133b76c * First run through the kernel's private parts to use phys_{addr,size}_t
where appropriate.
* Typedef'ed page_num_t to phys_addr_t and used it in more places in
  vm_page.{h,cpp}.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36937 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-05-25 21:34:08 +00:00
Ingo Weinhold
13fa4c845a * Introduced new area creation flag CREATE_AREA_DONT_COMMIT_MEMORY.
map_backing_store() doesn't commit memory when this flag is given.
* Used the new flag vm_copy_area(): We no longer commit memory for read-only
  areas. This prevents read-only mapped files from suddenly requiring memory
  after fork(). Might improve the situation on machines with very little RAM
  a bit.
  We should probably mark writable copies over-committing, since the usual
  case is fork() + exec() where the child normally doesn't need more than a
  few pages until calling exec(). That would significantly reduce the memory
  requirement for jamming the Haiku tree.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36651 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-05-06 14:59:14 +00:00
Ingo Weinhold
c1be1e0761 * VMTranslationMap::Map()/Protect(): Added "memoryType" parameter. Not
implemented for any architecture yet.
* vm_set_area_memory_type(): Call VMTranslationMap::ProtectArea() to change the
  memory type for the already mapped pages.



git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36574 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-05-01 21:33:12 +00:00
Ingo Weinhold
3b0c1b5227 * VMArea: Made memory_type private and added setter and getter methods.
* Don't set the VMArea's memory type in arch_vm_set_memory_type(), but let the
  callers do that.
* vm_set_area_memory_type(): Does nothing, if the memory type doesn't change.



git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36573 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-05-01 20:41:57 +00:00
Ingo Weinhold
907886143f * Changed some parameters of VM syscalls from int to uint32, mostly for sake
of consistency.
* Moved the B_OVERCOMMITTING_AREA flag from B_KERNEL_AREA_FLAGS to
  B_USER_AREA_FLAGS, since we really allow it to be passed from userland.
* Most VM syscalls check the provided protection against B_USER_AREA_FLAGS
  instead of B_USER_PROTECTION, now. This way they allow for
  B_OVERCOMMITTING_AREA as well.
* _user_map_file(), _user_set_memory_protection(): Check the protection like
  the other syscalls do and use fix_protection() instead of doing that
  manually.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36572 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-05-01 19:47:39 +00:00
Ingo Weinhold
b1e06d23ce * The "page_stats" command does now also print the longest contiguous runs of
free respective free and cached pages.
* Removed the unused vm_page_allocate_page_run_no_base().
* vm_page_allocate_page_run() (and allocate_page_run()):
  - Use vm_page_reserve_pages() instead of vm_page_try_reserve_pages(), i.e.
    wait until the reservation succeeds.
  - Now we iterates two times through the pages to find a suitable page run. In
    the first iteration it only looks for free/clear pages, in the second
    iteration it also considers cached pages. This increases the chance of the
    function to succeed, when a lot of caching is going on.
    This reduces the amount of memory required to use the IOCache when booting
    off the anyboot Live CD to around 160 MB in qemu. It also seems to work with
    128 MB, but the syslog indicates that some memory allocations fail, which
    is not exactly inspiring confidence.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36489 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-04-26 13:56:09 +00:00
Ingo Weinhold
efeca209a1 Made VMCache::Resize() virtual and let VMAnonymousCache override it to free
swap space when the cache shrinks. Currently the implementation stil leaks
swap space of busy pages.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36373 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-04-20 14:04:18 +00:00
Ingo Weinhold
c3676b54bf * Added vm_debug_copy_page_memory() which copies memory from a potentially not
mapped page.
* debug_{mem,strl}cpy():
  - Added "team" parameter for specifying the address space the address are
    to be interpreted in.
  - When the standard memcpy() (with fault handler) fails, fall back to
    vm_debug_copy_page_memory().
* Added debug_is_debugged_team(): Predicate returning true, if the supplied
  team_id refers to the same team debug_get_debugged_thread() belongs to.
* Added DebuggedThreadSetter class for scope-based debug_set_debugged_thread().
  Made use of it in several debugger functions.
* print_demangled_call() (x86): Fixed unsafe memory access.

Allows KDL stack traces to work correctly again, even if the page daemon has
already unmapped the concerned pages.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36230 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-04-13 17:40:15 +00:00
Ingo Weinhold
86875ad9d1 Added VMCache::DebugHasPage() and DebugLookupPage() for use in the kernel
debugger.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36228 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-04-13 17:18:57 +00:00
Ingo Weinhold
09418c869b Added DebugGet() method for use in the kernel debugger.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36227 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-04-13 17:16:42 +00:00
Ingo Weinhold
349039ff2e Added vm_[un]wire_page(), which are essentially versions of
[un]lock_memory_etc() optimized for a single page.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36156 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-04-11 15:07:06 +00:00
Ingo Weinhold
4f774c503c * VMArea::Unwire(addr_t, size_t, bool): Don't delete the removed range, but
return it.
* lock_memory_etc(): On error the VMAreaWiredRange object could be leaked.
* [un]lock_memory_etc(): Call VMArea::Unwire() with the cache locked and
  explicitly delete the range object after unlocking the cache to avoid
  potential deadlocks.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36035 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-04-05 12:12:36 +00:00
Ingo Weinhold
369111e741 * Removed the VMArea::Wire() version that has to allocate a VMAreaWiredRange.
Since the requirement is that the area's top cache is locked, allocating
  memory isn't allowed.
* lock_memory_etc(): Create the VMAreaWiredRange object explicitly before
  locking the area's top cache.

Fixes #5680 (deadlocks when using the slab as malloc() backend).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36033 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-04-05 11:08:01 +00:00
Ingo Weinhold
550376ffb8 * vm_delete_areas(): Changed return type to void (was status_t and not used).
* _user_map_file(), _user_unmap_memory(): Verify that the address (if given) is
  page aligned.
* Reworked memory locking (wiring):
  - VMArea does now have a list of wired memory ranges and supports waiting for
    a range to be removed.
  - vm_soft_fault():
    - Added "wirePage" parameter that, if given, makes the function wire the
      page and return it.
    - Added "wiredRange" parameter (for calls from lock_memory_etc()) and made
      sure we never unmap wired pages. This could e.g. happen when a page from a
      lower cache was read-mapped and a write fault occurred. Now in such a
      situation the function waits for the page to be unwired and restarts.
  - All functions that manipulate areas in a way that could affect wired ranges
    do now either require the caller to make sure there are no wired ranges in
    the way or do that themselves. Added a few wait_if_*_is_wired() helper
    functions for that purpose.
  - lock_memory_etc():
    - Does now also work correctly when the range spans more than one area.
    - Adds VMAreaWiredRanges to the affected VMAreas and retains an address
      space reference (so that the address space won't be deleted as long as a
      wired range exists).
    - Resolved TODO: The area's caches are now locked when
      increment_page_wired_count() is called.
    - Resolved TODO: The race condition due to missing locking after looking up
      the page mapping is now prevented. We hold the cache locks (in case the
      page is already mapped) and the new vm_soft_fault() parameter allows us
      to get the page wired.
  - unlock_memory_etc(): Changes symmetrical to those in lock_memory_etc() and
    resolved all TODOs.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36030 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-04-03 18:01:29 +00:00
Ingo Weinhold
fe0963a835 Added commands to the page access debugging panic()s.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@35904 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-03-18 16:19:13 +00:00
Ingo Weinhold
bd7645a12a * Made vm_page::state private and added accessor methods.
* Added kernel tracing for page state transitions.



git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@35538 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-02-20 15:57:44 +00:00
Ingo Weinhold
d36b9aef3e Added vm_page::IsMapped() for convenience.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@35531 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-02-20 12:29:42 +00:00
Ingo Weinhold
4bb4f79355 Added assert.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@35497 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-02-16 16:49:52 +00:00
Ingo Weinhold
40bb94819e * Removed useless return parameter from vm_remove_all_page_mappings().
* Added vm_clear_page_mapping_accessed_flags() and
  vm_remove_all_page_mappings_if_unaccessed(), which combine the functionality
  of vm_test_map_activation(), vm_clear_map_flags(), and
  vm_remove_all_page_mappings(), thus saving lots of calls to translation map
  methods. The backend is the new method
  VMTranslationMap::ClearAccessedAndModified().
* Started to make use of the cached page queue and changed the meaning of the
  other non-free queues slightly:
  - Active queue: Contains mapped pages that have been used recently.
  - Inactive queue: Contains mapped pages that have not been used recently. Also
    contains unmapped temporary pages.
  - Modified queue: Contains unmapped modified pages.
  - Cached queue: Contains unmapped unmodified pages (LRU sorted).
  Unless we're actually low on memory and actively do paging, modified and
  cached queues only contain non-temporary pages. Cached pages are considered
  quasi free. They still belong to a cache, but since they are unmodified and
  unmapped, they can be freed immediately. And this is what
  vm_page_[try_]reserve_pages() do now when there are no more actually free
  pages at hand. Essentially this means that pages storing cached file data,
  unless mmap()ped, no longer are considered used and don't contribute to page
  pressure. Paging will not happen as long there are enough free + cached pages
  available.
* Reimplemented the page daemon. It no longer scans all pages, but instead works
  the page queues. As long as the free pages situation is harmless, it only
  iterates through the active queue and deactivates pages that have not been
  used recently. When paging occurs it additionally scans the inactive queue and
  frees pages that have not been used recently.
* Changed the page reservation/allocation interface:
  vm_page_[try_]reserve_pages(), vm_page_unreserve_pages(), and
  vm_page_allocate_page() now take a vm_page_reservation structure pointer.
  The reservation functions initialize the structure -- currently consisting
  only of a count member for the number of still reserved pages.
  vm_page_allocate_page() decrements the count and vm_page_unreserve_pages()
  unreserves the remaining pages (if any). Advantages are that reservation/
  unreservation mismatches cannot occur anymore, that vm_page_allocate_page()
  can verify that the caller has indeed a reserved page left, and that there's
  no unnecessary pressure on the free page pool anymore. The only disadvantage
  is that the vm_page_reservation object needs to be passed around a bit.
* Reworked the page reservation implementation:
  - Got rid of sSystemReservedPages and sPageDeficit. Instead
    sUnreservedFreePages now actually contains the number of free pages that
    have not yet been reserved (it cannot become negative anymore) and the new
    sUnsatisfiedPageReservations contains the number of pages that are still
    needed for reservation.
  - Threads waiting for reservations do now add themselves to a waiter queue,
    which is ordered by descending priority (VM priority and thread priority).
    High priority waiters are served first when pages become available.
  Fixes #5328.
* cache_prefetch_vnode(): Would reserve one less page than allocated later, if
  the size wasn't page aligned.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@35393 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-02-03 18:53:52 +00:00
Ingo Weinhold
cf99b9ab60 Added VMCache::CacheRef() accessor.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@35391 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-02-03 18:46:29 +00:00
Ingo Weinhold
e65c400299 * Replaced the vm_page_allocate_page*() "pageState" parameter by a more
general "flags" parameter. It encodes the target state of the page -- so
  that the page isn't unnecessarily put in the wrong page queue first -- a
  flag whether the page should be cleared, and one to indicate whether the
  page should be marked busy.
* Added page state PAGE_STATE_CACHED. Not used yet.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@35333 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-01-29 15:54:40 +00:00
Ingo Weinhold
72382fa629 * Removed the page state PAGE_STATE_BUSY and instead introduced a vm_page::busy
flag. The obvious advantage is that one can still see what state a page is in
  and even move it between states while being marked busy.
* Removed the vm_page::is_dummy flag. Instead we mark marker pages busy, which
  in all cases has the same effect. Introduced a vm_page_is_dummy() that can
  still check whether a given page is a dummy page.
* vm_page_unreserve_pages(): Before adding to the system reserve make sure
  sUnreservedFreePages is non-negative. Otherwise we'd make nonexisting pages
  available for allocation. steal_pages() still has the same problem and it
  can't be solved that easily.
* map_page(): No longer changes the page state/mark the page unbusy. That's the
  caller's responsibility.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@35331 a95241bf-73f2-0310-859d-f6bbb57e9c96
2010-01-29 10:00:45 +00:00