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/*++
Copyright (c) 2006, Intel Corporation
All rights reserved. This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
Module Name:
pool.c
Abstract:
EFI Memory pool management
Revision History
--*/
#include <DxeMain.h>
#define POOL_FREE_SIGNATURE EFI_SIGNATURE_32('p','f','r','0')
typedef struct {
UINT32 Signature;
UINT32 Index;
LIST_ENTRY Link;
} POOL_FREE;
#define POOL_HEAD_SIGNATURE EFI_SIGNATURE_32('p','h','d','0')
typedef struct {
UINT32 Signature;
UINT32 Size;
EFI_MEMORY_TYPE Type;
UINTN Reserved;
CHAR8 Data[1];
} POOL_HEAD;
#define SIZE_OF_POOL_HEAD EFI_FIELD_OFFSET(POOL_HEAD,Data)
#define POOL_TAIL_SIGNATURE EFI_SIGNATURE_32('p','t','a','l')
typedef struct {
UINT32 Signature;
UINT32 Size;
} POOL_TAIL;
#define POOL_SHIFT 7
#define POOL_OVERHEAD (SIZE_OF_POOL_HEAD + sizeof(POOL_TAIL))
#define HEAD_TO_TAIL(a) \
((POOL_TAIL *) (((CHAR8 *) (a)) + (a)->Size - sizeof(POOL_TAIL)));
#define SIZE_TO_LIST(a) ((a) >> POOL_SHIFT)
#define LIST_TO_SIZE(a) ((a+1) << POOL_SHIFT)
#define MAX_POOL_LIST SIZE_TO_LIST(DEFAULT_PAGE_ALLOCATION)
#define MAX_POOL_SIZE (MAX_ADDRESS - POOL_OVERHEAD)
//
// Globals
//
#define POOL_SIGNATURE EFI_SIGNATURE_32('p','l','s','t')
typedef struct {
INTN Signature;
UINTN Used;
EFI_MEMORY_TYPE MemoryType;
LIST_ENTRY FreeList[MAX_POOL_LIST];
LIST_ENTRY Link;
} POOL;
POOL PoolHead[EfiMaxMemoryType];
LIST_ENTRY PoolHeadList;
//
//
//
VOID
CoreInitializePool (
VOID
)
/*++
Routine Description:
Called to initialize the pool.
Arguments:
None
Returns:
None
--*/
{
UINTN Type;
UINTN Index;
for (Type=0; Type < EfiMaxMemoryType; Type++) {
PoolHead[Type].Signature = 0;
PoolHead[Type].Used = 0;
PoolHead[Type].MemoryType = Type;
for (Index=0; Index < MAX_POOL_LIST; Index++) {
InitializeListHead (&PoolHead[Type].FreeList[Index]);
}
}
InitializeListHead (&PoolHeadList);
}
POOL *
LookupPoolHead (
IN EFI_MEMORY_TYPE MemoryType
)
/*++
Routine Description:
Look up pool head for specified memory type.
Arguments:
MemoryType - Memory type of which pool head is looked for
Returns:
Pointer of Corresponding pool head.
--*/
{
LIST_ENTRY *Link;
POOL *Pool;
UINTN Index;
if (MemoryType >= 0 && MemoryType < EfiMaxMemoryType) {
return &PoolHead[MemoryType];
}
if (MemoryType < 0) {
for (Link = PoolHeadList.ForwardLink; Link != &PoolHeadList; Link = Link->ForwardLink) {
Pool = CR(Link, POOL, Link, POOL_SIGNATURE);
if (Pool->MemoryType == MemoryType) {
return Pool;
}
}
Pool = CoreAllocatePoolI (EfiBootServicesData, sizeof (POOL));
if (Pool == NULL) {
return NULL;
}
Pool->Signature = POOL_SIGNATURE;
Pool->Used = 0;
Pool->MemoryType = MemoryType;
for (Index=0; Index < MAX_POOL_LIST; Index++) {
InitializeListHead (&Pool->FreeList[Index]);
}
InsertHeadList (&PoolHeadList, &Pool->Link);
return Pool;
}
return NULL;
}
EFI_STATUS
EFIAPI
CoreAllocatePool (
IN EFI_MEMORY_TYPE PoolType,
IN UINTN Size,
OUT VOID **Buffer
)
/*++
Routine Description:
Allocate pool of a particular type.
Arguments:
PoolType - Type of pool to allocate
Size - The amount of pool to allocate
Buffer - The address to return a pointer to the allocated pool
Returns:
EFI_INVALID_PARAMETER - PoolType not valid
EFI_OUT_OF_RESOURCES - Size exceeds max pool size or allocation failed.
EFI_SUCCESS - Pool successfully allocated.
--*/
{
EFI_STATUS Status;
//
// If it's not a valid type, fail it
//
if ((PoolType >= EfiMaxMemoryType && PoolType <= 0x7fffffff) ||
PoolType == EfiConventionalMemory) {
return EFI_INVALID_PARAMETER;
}
*Buffer = NULL;
//
// If size is too large, fail it
// Base on the EFI spec, return status of EFI_OUT_OF_RESOURCES
//
if (Size > MAX_POOL_SIZE) {
return EFI_OUT_OF_RESOURCES;
}
//
// Acquire the memory lock and make the allocation
//
Status = CoreAcquireLockOrFail (&gMemoryLock);
if (EFI_ERROR (Status)) {
return EFI_OUT_OF_RESOURCES;
}
*Buffer = CoreAllocatePoolI (PoolType, Size);
CoreReleaseMemoryLock ();
return (*Buffer != NULL) ? EFI_SUCCESS : EFI_OUT_OF_RESOURCES;
}
VOID *
CoreAllocatePoolI (
IN EFI_MEMORY_TYPE PoolType,
IN UINTN Size
)
/*++
Routine Description:
Internal function to allocate pool of a particular type.
Caller must have the memory lock held
Arguments:
PoolType - Type of pool to allocate
Size - The amount of pool to allocate
Returns:
The allocate pool, or NULL
--*/
{
POOL *Pool;
POOL_FREE *Free;
POOL_HEAD *Head;
POOL_TAIL *Tail;
CHAR8 *NewPage;
VOID *Buffer;
UINTN Index;
UINTN FSize;
UINTN offset;
UINTN Adjustment;
UINTN NoPages;
ASSERT_LOCKED (&gMemoryLock);
//
// Adjust the size by the pool header & tail overhead
//
//
// Adjusting the Size to be of proper alignment so that
// we don't get an unaligned access fault later when
// pool_Tail is being initialized
//
ALIGN_VARIABLE (Size, Adjustment);
Size += POOL_OVERHEAD;
Index = SIZE_TO_LIST(Size);
Pool = LookupPoolHead (PoolType);
if (Pool== NULL) {
return NULL;
}
Head = NULL;
//
// If allocation is over max size, just allocate pages for the request
// (slow)
//
if (Index >= MAX_POOL_LIST) {
NoPages = EFI_SIZE_TO_PAGES(Size) + EFI_SIZE_TO_PAGES (DEFAULT_PAGE_ALLOCATION) - 1;
NoPages &= ~(EFI_SIZE_TO_PAGES (DEFAULT_PAGE_ALLOCATION) - 1);
Head = CoreAllocatePoolPages (PoolType, NoPages, DEFAULT_PAGE_ALLOCATION);
goto Done;
}
//
// If there's no free pool in the proper list size, go get some more pages
//
if (IsListEmpty (&Pool->FreeList[Index])) {
//
// Get another page
//
NewPage = CoreAllocatePoolPages(PoolType, EFI_SIZE_TO_PAGES (DEFAULT_PAGE_ALLOCATION), DEFAULT_PAGE_ALLOCATION);
if (NewPage == NULL) {
goto Done;
}
//
// Carve up new page into free pool blocks
//
offset = 0;
while (offset < DEFAULT_PAGE_ALLOCATION) {
ASSERT (Index < MAX_POOL_LIST);
FSize = LIST_TO_SIZE(Index);
while (offset + FSize <= DEFAULT_PAGE_ALLOCATION) {
Free = (POOL_FREE *) &NewPage[offset];
Free->Signature = POOL_FREE_SIGNATURE;
Free->Index = (UINT32)Index;
InsertHeadList (&Pool->FreeList[Index], &Free->Link);
offset += FSize;
}
Index -= 1;
}
ASSERT (offset == DEFAULT_PAGE_ALLOCATION);
Index = SIZE_TO_LIST(Size);
}
//
// Remove entry from free pool list
//
Free = CR (Pool->FreeList[Index].ForwardLink, POOL_FREE, Link, POOL_FREE_SIGNATURE);
RemoveEntryList (&Free->Link);
Head = (POOL_HEAD *) Free;
Done:
Buffer = NULL;
if (Head != NULL) {
//
// If we have a pool buffer, fill in the header & tail info
//
Head->Signature = POOL_HEAD_SIGNATURE;
Head->Size = (UINT32) Size;
Head->Type = (EFI_MEMORY_TYPE) PoolType;
Tail = HEAD_TO_TAIL (Head);
Tail->Signature = POOL_TAIL_SIGNATURE;
Tail->Size = (UINT32) Size;
Buffer = Head->Data;
DEBUG_CLEAR_MEMORY (Buffer, Size - POOL_OVERHEAD);
DEBUG (
(EFI_D_POOL,
"AllcocatePoolI: Type %x, Addr %x (len %x) %,d\n",
PoolType,
Buffer,
Size - POOL_OVERHEAD,
Pool->Used)
);
//
// Account the allocation
//
Pool->Used += Size;
} else {
DEBUG ((EFI_D_ERROR | EFI_D_POOL, "AllocatePool: failed to allocate %d bytes\n", Size));
}
return Buffer;
}
EFI_STATUS
EFIAPI
CoreFreePool (
IN VOID *Buffer
)
/*++
Routine Description:
Frees pool.
Arguments:
Buffer - The allocated pool entry to free
Returns:
EFI_INVALID_PARAMETER - Buffer is not a valid value.
EFI_SUCCESS - Pool successfully freed.
--*/
{
EFI_STATUS Status;
if (NULL == Buffer) {
return EFI_INVALID_PARAMETER;
}
CoreAcquireMemoryLock ();
Status = CoreFreePoolI (Buffer);
CoreReleaseMemoryLock ();
return Status;
}
EFI_STATUS
CoreFreePoolI (
IN VOID *Buffer
)
/*++
Routine Description:
Internal function to free a pool entry.
Caller must have the memory lock held
Arguments:
Buffer - The allocated pool entry to free
Returns:
EFI_INVALID_PARAMETER - Buffer not valid
EFI_SUCCESS - Buffer successfully freed.
--*/
{
POOL *Pool;
POOL_HEAD *Head;
POOL_TAIL *Tail;
POOL_FREE *Free;
UINTN Index;
UINTN NoPages;
UINTN Size;
CHAR8 *NewPage;
UINTN FSize;
UINTN offset;
BOOLEAN AllFree;
ASSERT(NULL != Buffer);
//
// Get the head & tail of the pool entry
//
Head = CR (Buffer, POOL_HEAD, Data, POOL_HEAD_SIGNATURE);
ASSERT(NULL != Head);
if (Head->Signature != POOL_HEAD_SIGNATURE) {
return EFI_INVALID_PARAMETER;
}
Tail = HEAD_TO_TAIL (Head);
ASSERT(NULL != Tail);
//
// Debug
//
ASSERT (Tail->Signature == POOL_TAIL_SIGNATURE);
ASSERT (Head->Size == Tail->Size);
ASSERT_LOCKED (&gMemoryLock);
if (Tail->Signature != POOL_TAIL_SIGNATURE) {
return EFI_INVALID_PARAMETER;
}
if (Head->Size != Tail->Size) {
return EFI_INVALID_PARAMETER;
}
//
// Determine the pool type and account for it
//
Size = Head->Size;
Pool = LookupPoolHead (Head->Type);
if (Pool == NULL) {
return EFI_INVALID_PARAMETER;
}
Pool->Used -= Size;
DEBUG ((EFI_D_POOL, "FreePool: %x (len %x) %,d\n", Head->Data, Head->Size - POOL_OVERHEAD, Pool->Used));
//
// Determine the pool list
//
Index = SIZE_TO_LIST(Size);
DEBUG_CLEAR_MEMORY (Head, Size);
//
// If it's not on the list, it must be pool pages
//
if (Index >= MAX_POOL_LIST) {
//
// Return the memory pages back to free memory
//
NoPages = EFI_SIZE_TO_PAGES(Size) + EFI_SIZE_TO_PAGES (DEFAULT_PAGE_ALLOCATION) - 1;
NoPages &= ~(EFI_SIZE_TO_PAGES (DEFAULT_PAGE_ALLOCATION) - 1);
CoreFreePoolPages ((EFI_PHYSICAL_ADDRESS) (UINTN) Head, NoPages);
} else {
//
// Put the pool entry onto the free pool list
//
Free = (POOL_FREE *) Head;
ASSERT(NULL != Free);
Free->Signature = POOL_FREE_SIGNATURE;
Free->Index = (UINT32)Index;
InsertHeadList (&Pool->FreeList[Index], &Free->Link);
//
// See if all the pool entries in the same page as Free are freed pool
// entries
//
NewPage = (CHAR8 *)((UINTN)Free & ~((DEFAULT_PAGE_ALLOCATION) -1));
Free = (POOL_FREE *) &NewPage[0];
ASSERT(NULL != Free);
if (Free->Signature == POOL_FREE_SIGNATURE) {
Index = Free->Index;
AllFree = TRUE;
offset = 0;
while ((offset < DEFAULT_PAGE_ALLOCATION) && (AllFree)) {
FSize = LIST_TO_SIZE(Index);
while (offset + FSize <= DEFAULT_PAGE_ALLOCATION) {
Free = (POOL_FREE *) &NewPage[offset];
ASSERT(NULL != Free);
if (Free->Signature != POOL_FREE_SIGNATURE) {
AllFree = FALSE;
}
offset += FSize;
}
Index -= 1;
}
if (AllFree) {
//
// All of the pool entries in the same page as Free are free pool
// entries
// Remove all of these pool entries from the free loop lists.
//
Free = (POOL_FREE *) &NewPage[0];
ASSERT(NULL != Free);
Index = Free->Index;
offset = 0;
while (offset < DEFAULT_PAGE_ALLOCATION) {
FSize = LIST_TO_SIZE(Index);
while (offset + FSize <= DEFAULT_PAGE_ALLOCATION) {
Free = (POOL_FREE *) &NewPage[offset];
ASSERT(NULL != Free);
RemoveEntryList (&Free->Link);
offset += FSize;
}
Index -= 1;
}
//
// Free the page
//
CoreFreePoolPages ((EFI_PHYSICAL_ADDRESS) (UINTN)NewPage, EFI_SIZE_TO_PAGES (DEFAULT_PAGE_ALLOCATION));
}
}
}
//
// If this is an OS specific memory type, then check to see if the last
// portion of that memory type has been freed. If it has, then free the
// list entry for that memory type
//
if (Pool->MemoryType < 0 && Pool->Used == 0) {
RemoveEntryList (&Pool->Link);
CoreFreePoolI (Pool);
}
return EFI_SUCCESS;
}
|