Botan::mlock_allocator Class Reference

#include <locking_allocator.h>

Public Member Functions
void *	allocate (size_t num_elems, size_t elem_size)
bool	deallocate (void *p, size_t num_elems, size_t elem_size) noexcept
	mlock_allocator () noexcept
	mlock_allocator (const mlock_allocator &)=delete
	mlock_allocator (mlock_allocator &&)=delete
mlock_allocator &	operator= (const mlock_allocator &)=delete
mlock_allocator &	operator= (mlock_allocator &&)=delete
	~mlock_allocator ()

Static Public Member Functions
static mlock_allocator &	instance () noexcept

Detailed Description

Definition at line 19 of file locking_allocator.h.

Constructor & Destructor Documentation

mlock_allocator() [1/3]

Botan::mlock_allocator::mlock_allocator ( const mlock_allocator & )

delete

mlock_allocator() [2/3]

Botan::mlock_allocator::mlock_allocator ( mlock_allocator && )

delete

mlock_allocator() [3/3]

Botan::mlock_allocator::mlock_allocator ( )

noexcept

Definition at line 46 of file locking_allocator.cpp.

                                          {
   const size_t mem_to_lock = OS::get_memory_locking_limit();
   const size_t page_size = OS::system_page_size();
 
   if(mem_to_lock > 0 && mem_to_lock % page_size == 0) {
      m_locked_pages = OS::allocate_locked_pages(mem_to_lock / page_size);
 
      if(!m_locked_pages.empty()) {
         m_pool = std::make_unique<Memory_Pool>(m_locked_pages, page_size);
      }
   }
}

References Botan::OS::allocate_locked_pages(), Botan::OS::get_memory_locking_limit(), and Botan::OS::system_page_size().

~mlock_allocator()

Botan::mlock_allocator::~mlock_allocator

(

)

Definition at line 59 of file locking_allocator.cpp.

                                  {
   if(m_pool) {
      m_pool.reset();
      // OS::free_locked_pages scrubs the memory before free
      OS::free_locked_pages(m_locked_pages);
   }
}

References Botan::OS::free_locked_pages().

Member Function Documentation

allocate()

void * Botan::mlock_allocator::allocate	(	size_t	num_elems,
		size_t	elem_size )

Definition at line 17 of file locking_allocator.cpp.

                                                                  {
   if(!m_pool) {
      return nullptr;
   }
 
   if(auto n = checked_mul(num_elems, elem_size)) {
      return m_pool->allocate(n.value());
   } else {
      // overflow!
      return nullptr;
   }
}

References Botan::checked_mul().

deallocate()

bool Botan::mlock_allocator::deallocate ( void * p, size_t num_elems, size_t elem_size )

noexcept

Definition at line 30 of file locking_allocator.cpp.

                                                                                     {
   if(!m_pool) {
      return false;
   }
 
   if(auto n = checked_mul(num_elems, elem_size)) {
      return m_pool->deallocate(p, n.value());
   } else {
      /*
      We return nullptr in allocate if there was an overflow, so if an
      overflow occurs here we know the pointer was not allocated by this pool.
      */
      return false;
   }
}

References Botan::checked_mul().

instance()

mlock_allocator & Botan::mlock_allocator::instance ( )

staticnoexcept

Definition at line 74 of file locking_allocator.cpp.

                                                    {
   return g_mlock_allocator;
}

Referenced by Botan::allocate_memory(), Botan::deallocate_memory(), and Botan::initialize_allocator().

operator=() [1/2]

mlock_allocator & Botan::mlock_allocator::operator= ( const mlock_allocator & )

delete

operator=() [2/2]

mlock_allocator & Botan::mlock_allocator::operator= ( mlock_allocator && )

delete

---

The documentation for this class was generated from the following files:

• src/lib/utils/locking_allocator/locking_allocator.h
• src/lib/utils/locking_allocator/locking_allocator.cpp