/**
Internal function. Used by the pool functions to allocate pages
to back pool allocation requests.
@param PoolType The type of memory for the new pool pages
@param NoPages No of pages to allocate
@param Granularity Bits to align.
@param NeedGuard Flag to indicate Guard page is needed or not
@return The allocated memory, or NULL
**/
STATIC
VOID *
CoreAllocatePoolPagesI (
IN EFI_MEMORY_TYPE PoolType,
IN UINTN NoPages,
IN UINTN Granularity,
IN BOOLEAN NeedGuard
)
{
VOID *Buffer;
EFI_STATUS Status;
Status = CoreAcquireLockOrFail (&gMemoryLock);
if (EFI_ERROR (Status)) {
return NULL;
}
Buffer = CoreAllocatePoolPages (PoolType, NoPages, Granularity, NeedGuard);
CoreReleaseMemoryLock ();
if (Buffer != NULL) {
if (NeedGuard) {
SetGuardForMemory ((EFI_PHYSICAL_ADDRESS)(UINTN)Buffer, NoPages);
}
ApplyMemoryProtectionPolicy(EfiConventionalMemory, PoolType,
(EFI_PHYSICAL_ADDRESS)(UINTN)Buffer, EFI_PAGES_TO_SIZE (NoPages));
}
return Buffer;
}
/**
Helper function of memory allocation with Guard pages.
@param FreePageList The free page node.
@param NumberOfPages Number of pages to be allocated.
@param MaxAddress Request to allocate memory below this address.
@param MemoryType Type of memory requested.
@return Memory address of allocated pages.
**/
UINTN
InternalAllocMaxAddressWithGuard (
IN OUT LIST_ENTRY *FreePageList,
IN UINTN NumberOfPages,
IN UINTN MaxAddress,
IN EFI_MEMORY_TYPE MemoryType
)
{
LIST_ENTRY *Node;
FREE_PAGE_LIST *Pages;
UINTN PagesToAlloc;
UINTN HeadGuard;
UINTN TailGuard;
UINTN Address;
for (Node = FreePageList->BackLink; Node != FreePageList;
Node = Node->BackLink) {
Pages = BASE_CR (Node, FREE_PAGE_LIST, Link);
if (Pages->NumberOfPages >= NumberOfPages &&
(UINTN)Pages + EFI_PAGES_TO_SIZE (NumberOfPages) - 1 <= MaxAddress) {
//
// We may need 1 or 2 more pages for Guard. Check it out.
//
PagesToAlloc = NumberOfPages;
TailGuard = (UINTN)Pages + EFI_PAGES_TO_SIZE (Pages->NumberOfPages);
if (!IsGuardPage (TailGuard)) {
//
// Add one if no Guard at the end of current free memory block.
//
PagesToAlloc += 1;
TailGuard = 0;
}
HeadGuard = (UINTN)Pages +
EFI_PAGES_TO_SIZE (Pages->NumberOfPages - PagesToAlloc) -
EFI_PAGE_SIZE;
if (!IsGuardPage (HeadGuard)) {
//
// Add one if no Guard at the page before the address to allocate
//
PagesToAlloc += 1;
HeadGuard = 0;
}
if (Pages->NumberOfPages < PagesToAlloc) {
// Not enough space to allocate memory with Guards? Try next block.
continue;
}
Address = InternalAllocPagesOnOneNode (Pages, PagesToAlloc, MaxAddress);
ConvertSmmMemoryMapEntry(MemoryType, Address, PagesToAlloc, FALSE);
CoreFreeMemoryMapStack();
if (HeadGuard == 0) {
// Don't pass the Guard page to user.
Address += EFI_PAGE_SIZE;
}
SetGuardForMemory (Address, NumberOfPages);
return Address;
}
}
return (UINTN)(-1);
}
