https://git.reactos.org/?p=reactos.git;a=commitdiff;h=d0f6d2cf6eb781b188103…
commit d0f6d2cf6eb781b188103ae5157f67fa6040a493
Author: Timo Kreuzer <timo.kreuzer(a)reactos.org>
AuthorDate: Sun Jun 13 11:26:06 2021 +0200
Commit: Timo Kreuzer <timo.kreuzer(a)reactos.org>
CommitDate: Sat Jun 19 12:01:24 2021 +0200
[FREELDR/x64] Allow using memory above 4GB on x64
This splits MM_MAX_PAGE into the maximum addressable PFN (which is 2^20-1 on x86, 2^26-1 on x86PAE and 2^36-1 on x64) and the maximum mapped/accessible virtual memory MM_MAX_PAGE_LOADER (which is 4 GB on x86, since paging is disabled, but only 1 GB on x64, since only that much is identity-mapped).
---
boot/freeldr/freeldr/include/mm.h | 10 ++++++++--
boot/freeldr/freeldr/lib/mm/meminit.c | 6 +++---
2 files changed, 11 insertions(+), 5 deletions(-)
diff --git a/boot/freeldr/freeldr/include/mm.h b/boot/freeldr/freeldr/include/mm.h
index dd1bb195633..a3f34a55f78 100644
--- a/boot/freeldr/freeldr/include/mm.h
+++ b/boot/freeldr/freeldr/include/mm.h
@@ -51,7 +51,12 @@ typedef struct _FREELDR_MEMORY_DESCRIPTOR
#define MM_PAGE_SIZE 4096
#define MM_PAGE_MASK 0xFFF
#define MM_PAGE_SHIFT 12
-#define MM_MAX_PAGE 0xFFFFF
+#if defined(_X86PAE_)
+#define MM_MAX_PAGE 0x3FFFFFF /* 26 bits for the PFN */
+#else
+#define MM_MAX_PAGE 0xFFFFF /* 20 bits for the PFN */
+#endif
+#define MM_MAX_PAGE_LOADER 0xFFFFF /* 4 GB flat address range */
#define MM_SIZE_TO_PAGES(a) \
( ((a) >> MM_PAGE_SHIFT) + ((a) & MM_PAGE_MASK ? 1 : 0) )
@@ -63,7 +68,8 @@ typedef struct _FREELDR_MEMORY_DESCRIPTOR
#define MM_PAGE_SIZE 4096
#define MM_PAGE_MASK 0xFFF
#define MM_PAGE_SHIFT 12
-#define MM_MAX_PAGE 0x3FFFF /* freeldr only maps 1 GB */
+#define MM_MAX_PAGE 0xFFFFFFFFF /* 36 bits for the PFN */
+#define MM_MAX_PAGE_LOADER 0x3FFFF /* on x64 freeldr only maps 1 GB */
#define MM_SIZE_TO_PAGES(a) \
( ((a) >> MM_PAGE_SHIFT) + ((a) & MM_PAGE_MASK ? 1 : 0) )
diff --git a/boot/freeldr/freeldr/lib/mm/meminit.c b/boot/freeldr/freeldr/lib/mm/meminit.c
index 8276cb8ca57..37a705a0c68 100644
--- a/boot/freeldr/freeldr/lib/mm/meminit.c
+++ b/boot/freeldr/freeldr/lib/mm/meminit.c
@@ -1,7 +1,7 @@
/*
* FreeLoader
* Copyright (C) 2006-2008 Aleksey Bragin <aleksey(a)reactos.org>
- * Copyright (C) 2006-2009 Herv� Poussineau <hpoussin(a)reactos.org>
+ * Copyright (C) 2006-2009 Hervé Poussineau <hpoussin(a)reactos.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -438,7 +438,7 @@ PVOID MmFindLocationForPageLookupTable(PFN_NUMBER TotalPageCount)
if (MemoryDescriptor->BasePage < CandidateBasePage) continue;
// Continue, if the address is too high
- if (MemoryDescriptor->BasePage + RequiredPages >= MM_MAX_PAGE) continue;
+ if (MemoryDescriptor->BasePage + RequiredPages >= MM_MAX_PAGE_LOADER) continue;
// Memory block is more suitable than the previous one
CandidateBasePage = MemoryDescriptor->BasePage;
@@ -447,7 +447,7 @@ PVOID MmFindLocationForPageLookupTable(PFN_NUMBER TotalPageCount)
// Calculate the end address for the lookup table
PageLookupTableEndPage = min(CandidateBasePage + CandidatePageCount,
- MM_MAX_PAGE);
+ MM_MAX_PAGE_LOADER);
// Calculate the virtual address
PageLookupTableMemAddress = (PVOID)((PageLookupTableEndPage * PAGE_SIZE)