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| author | Star Zeng <star.zeng@intel.com> | 2015-07-27 03:04:41 +0000 |
|---|---|---|
| committer | lzeng14 <lzeng14@Edk2> | 2015-07-27 03:04:41 +0000 |
| commit | 716087e2becafbac134a2cbd5e7cc6da684adc74 (patch) | |
| tree | abdad696191ad4cbccf0e38364a8f0816d1161ac /MdeModulePkg/Universal/CapsulePei/X64/PageFaultHandler.asm | |
| parent | 353f5ba92f9420266bbf5dd86c3faae35db6a478 (diff) | |
| download | edk2-platforms-716087e2becafbac134a2cbd5e7cc6da684adc74.tar.xz | |
MdeModulePkg CapsuleX64: Reduce reserved memory consumption
We are going to reduce reserved memory consumption by page table buffer,
then OS can have more available memory to use.
Take PhysicalAddressBits = 48 and 2MB page granularity as example,
1:1 Virtual to Physical identity mapping page table buffer needs to be
((512 + 1) * 512 + 1) * 4096 = 1075843072 bytes = 0x40201000 bytes.
The code is updated to build 4G page table by default and only use 8 extra
pages to handles > 4G request by page fault.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18069 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'MdeModulePkg/Universal/CapsulePei/X64/PageFaultHandler.asm')
| -rw-r--r-- | MdeModulePkg/Universal/CapsulePei/X64/PageFaultHandler.asm | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/MdeModulePkg/Universal/CapsulePei/X64/PageFaultHandler.asm b/MdeModulePkg/Universal/CapsulePei/X64/PageFaultHandler.asm new file mode 100644 index 0000000000..2f1eab72ef --- /dev/null +++ b/MdeModulePkg/Universal/CapsulePei/X64/PageFaultHandler.asm @@ -0,0 +1,87 @@ +;; @file
+; This is the assembly code for page fault handler hook.
+;
+; Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
+;
+; 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.
+;
+;;
+
+EXTERN PageFaultHandler:PROC
+
+ .code
+
+PageFaultHandlerHook PROC
+ add rsp, -10h
+ ; save rax
+ mov [rsp + 08h], rax
+
+ ;push rax ; save all volatile registers
+ push rcx
+ push rdx
+ push r8
+ push r9
+ push r10
+ push r11
+ ; save volatile fp registers
+ ; 68h + 08h(for alignment)
+ add rsp, -70h
+ stmxcsr [rsp + 60h]
+ movdqa [rsp + 0h], xmm0
+ movdqa [rsp + 10h], xmm1
+ movdqa [rsp + 20h], xmm2
+ movdqa [rsp + 30h], xmm3
+ movdqa [rsp + 40h], xmm4
+ movdqa [rsp + 50h], xmm5
+
+ add rsp, -20h
+ call PageFaultHandler
+ add rsp, 20h
+
+ ; load volatile fp registers
+ ldmxcsr [rsp + 60h]
+ movdqa xmm0, [rsp + 0h]
+ movdqa xmm1, [rsp + 10h]
+ movdqa xmm2, [rsp + 20h]
+ movdqa xmm3, [rsp + 30h]
+ movdqa xmm4, [rsp + 40h]
+ movdqa xmm5, [rsp + 50h]
+ add rsp, 70h
+
+ pop r11
+ pop r10
+ pop r9
+ pop r8
+ pop rdx
+ pop rcx
+ ;pop rax ; restore all volatile registers
+
+ add rsp, 10h
+
+ ; rax returned from PageFaultHandler is NULL or OriginalHandler address
+ ; NULL if the page fault is handled by PageFaultHandler
+ ; OriginalHandler address if the page fault is not handled by PageFaultHandler
+ test rax, rax
+
+ ; save OriginalHandler address
+ mov [rsp - 10h], rax
+ ; restore rax
+ mov rax, [rsp - 08h]
+
+ jz @F
+
+ ; jump to OriginalHandler
+ jmp qword ptr [rsp - 10h]
+
+@@:
+ add rsp, 08h ; skip error code for PF
+ iretq
+PageFaultHandlerHook ENDP
+
+ END
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