DEBUG_CACHE_LIST) that prints an unspectacular list of pointers to all
existing caches. Feel free to extend.
* Enhanced MultiAddressSpaceLocker:
- It supports choosing between read and write lock per address space,
now.
- Added AddAreaCacheAndLock(), which adds the address spaces of all
areas that are attached to a given area's cache, locks them, and
locks the cache. It makes sure that the area list didn't change in
the meantime and optionally also that all areas have their
no_cache_change flags cleared.
* Changed vm_copy_on_write_area() to take a cache instead of an area,
requiring it to be locked and all address spaces of affected areas to
be read-locked, plus all areas' no_cache_change flags to be cleared.
Callers simply use MultiAddressSpaceLocker:: AddAreaCacheAndLock() to
do that. This resolves an open TODO, that the areas' base, size, and
protection fields were accessed without their address spaces being
locked.
* vm_copy_area() does now always insert a cache for the target area. Not
doing that would cause source and target area being attached to
the same cache in case the target protection was read-only. This
would make them behave like cloned areas, which would lead to trouble
when one of the areas would be changed to writable later.
* Fixed the !writable -> writable case in vm_set_area_protection(). It
would simply change the protection of all mapped pages for this area,
including ones from lower caches, thus causing later writes to the
area to be seen by areas that shouldn't see them. This fixes a problem
with software breakpoints in gdb. They could cause other programs to
be dropped into the debugger.
* resize_area() uses MultiAddressSpaceLocker::AddAreaCacheAndLock() now,
too, and could be compacted quite a bit.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@22152 a95241bf-73f2-0310-859d-f6bbb57e9c96
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