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Kernel: Set up Regions before adding them to a Process's AddressSpace

This reduces the amount of time in which not fully-initialized Regions
are present inside an AddressSpace's region tree.
This commit is contained in:
Idan Horowitz 2022-02-10 19:55:10 +02:00
parent d9d3362722
commit 57bce8ab97
2 changed files with 10 additions and 12 deletions

View file

@ -146,16 +146,15 @@ ErrorOr<Region*> AddressSpace::try_allocate_split_region(Region const& source_re
auto new_region = TRY(Region::try_create_user_accessible( auto new_region = TRY(Region::try_create_user_accessible(
range, source_region.vmobject(), offset_in_vmobject, move(region_name), source_region.access(), source_region.is_cacheable() ? Region::Cacheable::Yes : Region::Cacheable::No, source_region.is_shared())); range, source_region.vmobject(), offset_in_vmobject, move(region_name), source_region.access(), source_region.is_cacheable() ? Region::Cacheable::Yes : Region::Cacheable::No, source_region.is_shared()));
auto* region = TRY(add_region(move(new_region))); new_region->set_syscall_region(source_region.is_syscall_region());
region->set_syscall_region(source_region.is_syscall_region()); new_region->set_mmap(source_region.is_mmap());
region->set_mmap(source_region.is_mmap()); new_region->set_stack(source_region.is_stack());
region->set_stack(source_region.is_stack());
size_t page_offset_in_source_region = (offset_in_vmobject - source_region.offset_in_vmobject()) / PAGE_SIZE; size_t page_offset_in_source_region = (offset_in_vmobject - source_region.offset_in_vmobject()) / PAGE_SIZE;
for (size_t i = 0; i < region->page_count(); ++i) { for (size_t i = 0; i < new_region->page_count(); ++i) {
if (source_region.should_cow(page_offset_in_source_region + i)) if (source_region.should_cow(page_offset_in_source_region + i))
TRY(region->set_should_cow(i, true)); TRY(new_region->set_should_cow(i, true));
} }
return region; return add_region(move(new_region));
} }
ErrorOr<Region*> AddressSpace::allocate_region(VirtualRange const& range, StringView name, int prot, AllocationStrategy strategy) ErrorOr<Region*> AddressSpace::allocate_region(VirtualRange const& range, StringView name, int prot, AllocationStrategy strategy)
@ -191,16 +190,15 @@ ErrorOr<Region*> AddressSpace::allocate_region_with_vmobject(VirtualRange const&
if (!name.is_null()) if (!name.is_null())
region_name = TRY(KString::try_create(name)); region_name = TRY(KString::try_create(name));
auto region = TRY(Region::try_create_user_accessible(range, move(vmobject), offset_in_vmobject, move(region_name), prot_to_region_access_flags(prot), Region::Cacheable::Yes, shared)); auto region = TRY(Region::try_create_user_accessible(range, move(vmobject), offset_in_vmobject, move(region_name), prot_to_region_access_flags(prot), Region::Cacheable::Yes, shared));
auto* added_region = TRY(add_region(move(region)));
if (prot == PROT_NONE) { if (prot == PROT_NONE) {
// For PROT_NONE mappings, we don't have to set up any page table mappings. // For PROT_NONE mappings, we don't have to set up any page table mappings.
// We do still need to attach the region to the page_directory though. // We do still need to attach the region to the page_directory though.
SpinlockLocker mm_locker(s_mm_lock); SpinlockLocker mm_locker(s_mm_lock);
added_region->set_page_directory(page_directory()); region->set_page_directory(page_directory());
} else { } else {
TRY(added_region->map(page_directory(), ShouldFlushTLB::No)); TRY(region->map(page_directory(), ShouldFlushTLB::No));
} }
return added_region; return add_region(move(region));
} }
void AddressSpace::deallocate_region(Region& region) void AddressSpace::deallocate_region(Region& region)

View file

@ -106,8 +106,8 @@ ErrorOr<FlatPtr> Process::sys$fork(RegisterState& regs)
for (auto& region : address_space().regions()) { for (auto& region : address_space().regions()) {
dbgln_if(FORK_DEBUG, "fork: cloning Region({}) '{}' @ {}", region, region->name(), region->vaddr()); dbgln_if(FORK_DEBUG, "fork: cloning Region({}) '{}' @ {}", region, region->name(), region->vaddr());
auto region_clone = TRY(region->try_clone()); auto region_clone = TRY(region->try_clone());
TRY(region_clone->map(child->address_space().page_directory(), Memory::ShouldFlushTLB::No));
auto* child_region = TRY(child->address_space().add_region(move(region_clone))); auto* child_region = TRY(child->address_space().add_region(move(region_clone)));
TRY(child_region->map(child->address_space().page_directory(), Memory::ShouldFlushTLB::No));
if (region == m_master_tls_region.unsafe_ptr()) if (region == m_master_tls_region.unsafe_ptr())
child->m_master_tls_region = child_region; child->m_master_tls_region = child_region;