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authorrtm <rtm>2006-08-29 19:06:37 +0000
committerrtm <rtm>2006-08-29 19:06:37 +0000
commitdfcc5b997ce9c313b9ac0e7d8da39c4416b472a8 (patch)
tree2d6c4e47bad6cfe7436896068a5872ace545a974 /mmu.h
parentd7ce6545e7179e9a4b950838c354b485e3f3fdb8 (diff)
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prune unneeded panics and debug output
Diffstat (limited to 'mmu.h')
-rw-r--r--mmu.h73
1 files changed, 7 insertions, 66 deletions
diff --git a/mmu.h b/mmu.h
index 0cd7944..8b30534 100644
--- a/mmu.h
+++ b/mmu.h
@@ -1,15 +1,8 @@
/*
- * This file contains definitions for the x86 memory management unit (MMU),
- * including paging- and segmentation-related data structures and constants,
- * the %cr0, %cr4, and %eflags registers, and traps.
+ * This file contains definitions for the x86 memory management unit (MMU).
+ * from JOS.
*/
-/*
- * Register flags and fundamental constants.
- */
-
-#define PGSIZE 4096 // bytes mapped by a page
-
// Eflags register
#define FL_CF 0x00000001 // Carry Flag
#define FL_PF 0x00000004 // Parity Flag
@@ -33,33 +26,7 @@
#define FL_VIP 0x00100000 // Virtual Interrupt Pending
#define FL_ID 0x00200000 // ID flag
-// Page fault error codes
-#define FEC_PR 0x1 // Page fault caused by protection violation
-#define FEC_WR 0x2 // Page fault caused by a write
-#define FEC_U 0x4 // Page fault occured while in user mode
-
-/*
- *
- * Segmentation data structures and constants.
- *
- */
-
-#ifdef __ASSEMBLER__
-
-/*
- * Macros to build GDT entries in assembly.
- */
-#define SEG_NULL \
- .word 0, 0; \
- .byte 0, 0, 0, 0
-#define SEG(type,base,lim) \
- .word (((lim) >> 12) & 0xffff), ((base) & 0xffff); \
- .byte (((base) >> 16) & 0xff), (0x90 | (type)), \
- (0xC0 | (((lim) >> 28) & 0xf)), (((base) >> 24) & 0xff)
-
-#else // not __ASSEMBLER__
-
-// Segment Descriptors
+// Segment Descriptor
struct segdesc {
uint lim_15_0 : 16; // Low bits of segment limit
uint base_15_0 : 16; // Low bits of segment base address
@@ -75,22 +42,21 @@ struct segdesc {
uint g : 1; // Granularity: limit scaled by 4K when set
uint base_31_24 : 8; // High bits of segment base address
};
+
// Null segment
#define SEG_NULL (struct segdesc){ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
-// Segment that is loadable but faults when used
-#define SEG_FAULT (struct segdesc){ 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0 }
+
// Normal segment
#define SEG(type, base, lim, dpl) (struct segdesc) \
{ ((lim) >> 12) & 0xffff, (base) & 0xffff, ((base) >> 16) & 0xff, \
type, 1, dpl, 1, (uint) (lim) >> 28, 0, 0, 1, 1, \
(uint) (base) >> 24 }
+
#define SEG16(type, base, lim, dpl) (struct segdesc) \
{ (lim) & 0xffff, (base) & 0xffff, ((base) >> 16) & 0xff, \
type, 1, dpl, 1, (uint) (lim) >> 16, 0, 0, 1, 0, \
(uint) (base) >> 24 }
-#endif /* !__ASSEMBLER__ */
-
// Application segment type bits
#define STA_X 0x8 // Executable segment
#define STA_E 0x4 // Expand down (non-executable segments)
@@ -113,16 +79,7 @@ struct segdesc {
#define STS_IG32 0xE // 32-bit Interrupt Gate
#define STS_TG32 0xF // 32-bit Trap Gate
-
-/*
- *
- * Traps.
- *
- */
-
-#ifndef __ASSEMBLER__
-
-// Task state segment format (as described by the Pentium architecture book)
+// Task state segment format
struct taskstate {
uint link; // Old ts selector
uint esp0; // Stack pointers and segment selectors
@@ -197,19 +154,3 @@ struct gatedesc {
(gate).off_31_16 = (uint) (off) >> 16; \
}
-// Set up a call gate descriptor.
-#define SETCALLGATE(gate, ss, off, d) \
-{ \
- (gate).off_15_0 = (uint) (off) & 0xffff; \
- (gate).ss = (ss); \
- (gate).args = 0; \
- (gate).rsv1 = 0; \
- (gate).type = STS_CG32; \
- (gate).s = 0; \
- (gate).dpl = (d); \
- (gate).p = 1; \
- (gate).off_31_16 = (uint) (off) >> 16; \
-}
-
-#endif /* !__ASSEMBLER__ */
-