1 /** @file
2 Implementation of the 6 PEI Ffs (FV) APIs in library form.
3
4 Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
5
6 SPDX-License-Identifier: BSD-2-Clause-Patent
7
8 **/
9
10 #include <PiPei.h>
11
12 #include <Library/BaseLib.h>
13 #include <Library/BaseMemoryLib.h>
14 #include <Library/PrePiLib.h>
15 #include <Library/DebugLib.h>
16
17
18
19 /**
20 Allocates one or more 4KB pages of type EfiBootServicesData.
21
22 Allocates the number of 4KB pages of MemoryType and returns a pointer to the
23 allocated buffer. The buffer returned is aligned on a 4KB boundary. If Pages is 0, then NULL
24 is returned. If there is not enough memory remaining to satisfy the request, then NULL is
25 returned.
26
27 @param Pages The number of 4 KB pages to allocate.
28
29 @return A pointer to the allocated buffer or NULL if allocation fails.
30
31 **/
32 VOID *
33 EFIAPI
AllocatePages(IN UINTN Pages)34 AllocatePages (
35 IN UINTN Pages
36 )
37 {
38 EFI_PEI_HOB_POINTERS Hob;
39 EFI_PHYSICAL_ADDRESS Offset;
40
41 Hob.Raw = GetHobList ();
42
43 // Check to see if on 4k boundary
44 Offset = Hob.HandoffInformationTable->EfiFreeMemoryTop & 0xFFF;
45 if (Offset != 0) {
46 // If not aligned, make the allocation aligned.
47 Hob.HandoffInformationTable->EfiFreeMemoryTop -= Offset;
48 }
49
50 //
51 // Verify that there is sufficient memory to satisfy the allocation
52 //
53 if (Hob.HandoffInformationTable->EfiFreeMemoryTop - ((Pages * EFI_PAGE_SIZE) + sizeof (EFI_HOB_MEMORY_ALLOCATION)) < Hob.HandoffInformationTable->EfiFreeMemoryBottom) {
54 return 0;
55 } else {
56 //
57 // Update the PHIT to reflect the memory usage
58 //
59 Hob.HandoffInformationTable->EfiFreeMemoryTop -= Pages * EFI_PAGE_SIZE;
60
61 // This routine used to create a memory allocation HOB a la PEI, but that's not
62 // necessary for us.
63
64 //
65 // Create a memory allocation HOB.
66 //
67 BuildMemoryAllocationHob (
68 Hob.HandoffInformationTable->EfiFreeMemoryTop,
69 Pages * EFI_PAGE_SIZE,
70 EfiBootServicesData
71 );
72 return (VOID *)(UINTN)Hob.HandoffInformationTable->EfiFreeMemoryTop;
73 }
74 }
75
76
77 /**
78 Allocates one or more 4KB pages of type EfiBootServicesData at a specified alignment.
79
80 Allocates the number of 4KB pages specified by Pages of type EfiBootServicesData with an
81 alignment specified by Alignment. The allocated buffer is returned. If Pages is 0, then NULL is
82 returned. If there is not enough memory at the specified alignment remaining to satisfy the
83 request, then NULL is returned.
84 If Alignment is not a power of two and Alignment is not zero, then ASSERT().
85
86 @param Pages The number of 4 KB pages to allocate.
87 @param Alignment The requested alignment of the allocation. Must be a power of two.
88 If Alignment is zero, then byte alignment is used.
89
90 @return A pointer to the allocated buffer or NULL if allocation fails.
91
92 **/
93 VOID *
94 EFIAPI
AllocateAlignedPages(IN UINTN Pages,IN UINTN Alignment)95 AllocateAlignedPages (
96 IN UINTN Pages,
97 IN UINTN Alignment
98 )
99 {
100 VOID *Memory;
101 UINTN AlignmentMask;
102
103 //
104 // Alignment must be a power of two or zero.
105 //
106 ASSERT ((Alignment & (Alignment - 1)) == 0);
107
108 if (Pages == 0) {
109 return NULL;
110 }
111 //
112 // Make sure that Pages plus EFI_SIZE_TO_PAGES (Alignment) does not overflow.
113 //
114 ASSERT (Pages <= (MAX_ADDRESS - EFI_SIZE_TO_PAGES (Alignment)));
115 //
116 // We would rather waste some memory to save PEI code size.
117 //
118 Memory = (VOID *)(UINTN)AllocatePages (Pages + EFI_SIZE_TO_PAGES (Alignment));
119 if (Alignment == 0) {
120 AlignmentMask = Alignment;
121 } else {
122 AlignmentMask = Alignment - 1;
123 }
124 return (VOID *) (UINTN) (((UINTN) Memory + AlignmentMask) & ~AlignmentMask);
125 }
126
127
128 /**
129 Frees one or more 4KB pages that were previously allocated with one of the page allocation
130 functions in the Memory Allocation Library.
131
132 Frees the number of 4KB pages specified by Pages from the buffer specified by Buffer. Buffer
133 must have been allocated on a previous call to the page allocation services of the Memory
134 Allocation Library. If it is not possible to free allocated pages, then this function will
135 perform no actions.
136
137 If Buffer was not allocated with a page allocation function in the Memory Allocation Library,
138 then ASSERT().
139 If Pages is zero, then ASSERT().
140
141 @param Buffer Pointer to the buffer of pages to free.
142 @param Pages The number of 4 KB pages to free.
143
144 **/
145 VOID
146 EFIAPI
FreePages(IN VOID * Buffer,IN UINTN Pages)147 FreePages (
148 IN VOID *Buffer,
149 IN UINTN Pages
150 )
151 {
152 // For now, we do not support the ability to free pages in the PrePei Memory Allocator.
153 // The allocated memory is lost.
154 }
155
156 /**
157 Allocates a buffer of type EfiBootServicesData.
158
159 Allocates the number bytes specified by AllocationSize of type EfiBootServicesData and returns a
160 pointer to the allocated buffer. If AllocationSize is 0, then a valid buffer of 0 size is
161 returned. If there is not enough memory remaining to satisfy the request, then NULL is returned.
162
163 @param AllocationSize The number of bytes to allocate.
164
165 @return A pointer to the allocated buffer or NULL if allocation fails.
166
167 **/
168 VOID *
169 EFIAPI
AllocatePool(IN UINTN AllocationSize)170 AllocatePool (
171 IN UINTN AllocationSize
172 )
173 {
174 EFI_HOB_MEMORY_POOL *Hob;
175
176 Hob = GetHobList ();
177
178
179 //
180 // Verify that there is sufficient memory to satisfy the allocation
181 //
182 if (AllocationSize > 0x10000) {
183 // Please call AllcoatePages for big allocations
184 return 0;
185 } else {
186
187 Hob = (EFI_HOB_MEMORY_POOL *)CreateHob (EFI_HOB_TYPE_MEMORY_POOL, (UINT16)(sizeof (EFI_HOB_TYPE_MEMORY_POOL) + AllocationSize));
188 return (VOID *)(Hob + 1);
189 }
190 }
191
192 /**
193 Allocates and zeros a buffer of type EfiBootServicesData.
194
195 Allocates the number bytes specified by AllocationSize of type EfiBootServicesData, clears the
196 buffer with zeros, and returns a pointer to the allocated buffer. If AllocationSize is 0, then a
197 valid buffer of 0 size is returned. If there is not enough memory remaining to satisfy the
198 request, then NULL is returned.
199
200 @param AllocationSize The number of bytes to allocate and zero.
201
202 @return A pointer to the allocated buffer or NULL if allocation fails.
203
204 **/
205 VOID *
206 EFIAPI
AllocateZeroPool(IN UINTN AllocationSize)207 AllocateZeroPool (
208 IN UINTN AllocationSize
209 )
210 {
211 VOID *Buffer;
212
213 Buffer = AllocatePool (AllocationSize);
214 if (Buffer == NULL) {
215 return NULL;
216 }
217
218 ZeroMem (Buffer, AllocationSize);
219
220 return Buffer;
221 }
222
223 /**
224 Frees a buffer that was previously allocated with one of the pool allocation functions in the
225 Memory Allocation Library.
226
227 Frees the buffer specified by Buffer. Buffer must have been allocated on a previous call to the
228 pool allocation services of the Memory Allocation Library. If it is not possible to free pool
229 resources, then this function will perform no actions.
230
231 If Buffer was not allocated with a pool allocation function in the Memory Allocation Library,
232 then ASSERT().
233
234 @param Buffer Pointer to the buffer to free.
235
236 **/
237 VOID
238 EFIAPI
FreePool(IN VOID * Buffer)239 FreePool (
240 IN VOID *Buffer
241 )
242 {
243 // Not implemented yet
244 }
245