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authorFrans Kaashoek <[email protected]>2018-08-30 13:14:01 -0400
committerFrans Kaashoek <[email protected]>2018-08-30 13:14:01 -0400
commit210a0f0b30eb1af49b6ed42339b1fcc8582ba653 (patch)
treea24d804200e1a800ed5c0dcb540ea3936bd9f14d
parentb2ca8e3e23e583991b4d8285be6569fb0dcf2495 (diff)
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Remove unused flags (thanks Wolfgang Keller)
-rw-r--r--asm.h3
-rw-r--r--mmu.h51
2 files changed, 4 insertions, 50 deletions
diff --git a/asm.h b/asm.h
index 68210d7..b8a7353 100644
--- a/asm.h
+++ b/asm.h
@@ -14,8 +14,5 @@
(0xC0 | (((lim) >> 28) & 0xf)), (((base) >> 24) & 0xff)
#define STA_X 0x8 // Executable segment
-#define STA_E 0x4 // Expand down (non-executable segments)
-#define STA_C 0x4 // Conforming code segment (executable only)
#define STA_W 0x2 // Writeable (non-executable segments)
#define STA_R 0x2 // Readable (executable segments)
-#define STA_A 0x1 // Accessed
diff --git a/mmu.h b/mmu.h
index 7b63db0..9d6673c 100644
--- a/mmu.h
+++ b/mmu.h
@@ -2,39 +2,11 @@
// x86 memory management unit (MMU).
// Eflags register
-#define FL_CF 0x00000001 // Carry Flag
-#define FL_PF 0x00000004 // Parity Flag
-#define FL_AF 0x00000010 // Auxiliary carry Flag
-#define FL_ZF 0x00000040 // Zero Flag
-#define FL_SF 0x00000080 // Sign Flag
-#define FL_TF 0x00000100 // Trap Flag
#define FL_IF 0x00000200 // Interrupt Enable
-#define FL_DF 0x00000400 // Direction Flag
-#define FL_OF 0x00000800 // Overflow Flag
-#define FL_IOPL_MASK 0x00003000 // I/O Privilege Level bitmask
-#define FL_IOPL_0 0x00000000 // IOPL == 0
-#define FL_IOPL_1 0x00001000 // IOPL == 1
-#define FL_IOPL_2 0x00002000 // IOPL == 2
-#define FL_IOPL_3 0x00003000 // IOPL == 3
-#define FL_NT 0x00004000 // Nested Task
-#define FL_RF 0x00010000 // Resume Flag
-#define FL_VM 0x00020000 // Virtual 8086 mode
-#define FL_AC 0x00040000 // Alignment Check
-#define FL_VIF 0x00080000 // Virtual Interrupt Flag
-#define FL_VIP 0x00100000 // Virtual Interrupt Pending
-#define FL_ID 0x00200000 // ID flag
// Control Register flags
#define CR0_PE 0x00000001 // Protection Enable
-#define CR0_MP 0x00000002 // Monitor coProcessor
-#define CR0_EM 0x00000004 // Emulation
-#define CR0_TS 0x00000008 // Task Switched
-#define CR0_ET 0x00000010 // Extension Type
-#define CR0_NE 0x00000020 // Numeric Errror
#define CR0_WP 0x00010000 // Write Protect
-#define CR0_AM 0x00040000 // Alignment Mask
-#define CR0_NW 0x20000000 // Not Writethrough
-#define CR0_CD 0x40000000 // Cache Disable
#define CR0_PG 0x80000000 // Paging
#define CR4_PSE 0x00000010 // Page size extension
@@ -82,23 +54,11 @@ struct segdesc {
// Application segment type bits
#define STA_X 0x8 // Executable segment
-#define STA_E 0x4 // Expand down (non-executable segments)
-#define STA_C 0x4 // Conforming code segment (executable only)
#define STA_W 0x2 // Writeable (non-executable segments)
#define STA_R 0x2 // Readable (executable segments)
-#define STA_A 0x1 // Accessed
// System segment type bits
-#define STS_T16A 0x1 // Available 16-bit TSS
-#define STS_LDT 0x2 // Local Descriptor Table
-#define STS_T16B 0x3 // Busy 16-bit TSS
-#define STS_CG16 0x4 // 16-bit Call Gate
-#define STS_TG 0x5 // Task Gate / Coum Transmitions
-#define STS_IG16 0x6 // 16-bit Interrupt Gate
-#define STS_TG16 0x7 // 16-bit Trap Gate
#define STS_T32A 0x9 // Available 32-bit TSS
-#define STS_T32B 0xB // Busy 32-bit TSS
-#define STS_CG32 0xC // 32-bit Call Gate
#define STS_IG32 0xE // 32-bit Interrupt Gate
#define STS_TG32 0xF // 32-bit Trap Gate
@@ -124,7 +84,6 @@ struct segdesc {
#define NPTENTRIES 1024 // # PTEs per page table
#define PGSIZE 4096 // bytes mapped by a page
-#define PGSHIFT 12 // log2(PGSIZE)
#define PTXSHIFT 12 // offset of PTX in a linear address
#define PDXSHIFT 22 // offset of PDX in a linear address
@@ -135,12 +94,7 @@ struct segdesc {
#define PTE_P 0x001 // Present
#define PTE_W 0x002 // Writeable
#define PTE_U 0x004 // User
-#define PTE_PWT 0x008 // Write-Through
-#define PTE_PCD 0x010 // Cache-Disable
-#define PTE_A 0x020 // Accessed
-#define PTE_D 0x040 // Dirty
#define PTE_PS 0x080 // Page Size
-#define PTE_MBZ 0x180 // Bits must be zero
// Address in page table or page directory entry
#define PTE_ADDR(pte) ((uint)(pte) & ~0xFFF)
@@ -197,7 +151,7 @@ struct gatedesc {
uint cs : 16; // code segment selector
uint args : 5; // # args, 0 for interrupt/trap gates
uint rsv1 : 3; // reserved(should be zero I guess)
- uint type : 4; // type(STS_{TG,IG32,TG32})
+ uint type : 4; // type(STS_{IG32,TG32})
uint s : 1; // must be 0 (system)
uint dpl : 2; // descriptor(meaning new) privilege level
uint p : 1; // Present
@@ -226,3 +180,6 @@ struct gatedesc {
}
#endif
+
+//PAGEBREAK!
+// Blank page.