slinky55/RockOS
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

added origin program

Browse Source
This commit is contained in:
slinky55
2026-06-16 18:44:31 -05:00
parent 0a51a5e8bc
commit 171cbd21bc
12 changed files with 262 additions and 28 deletions
Download Patch File Download Diff File Expand all files Collapse all files

65
kernel/gdt.c
View File

@@ -45,11 +45,44 @@ typedef struct __attribute__((packed)) {
uint16_t limit;
uint32_t base;
} gdt_ptr_t;
typedef struct __attribute__((packed)) {
uint32_t prev_tss;
uint32_t esp0;
uint32_t ss0;
uint32_t esp1;
uint32_t ss1;
uint32_t esp2;
uint32_t ss2;
uint32_t cr3;
uint32_t eip;
uint32_t eflags;
uint32_t eax;
uint32_t ecx;
uint32_t edx;
uint32_t ebx;
uint32_t esp;
uint32_t ebp;
uint32_t esi;
uint32_t edi;
uint32_t es;
uint32_t cs;
uint32_t ss;
uint32_t ds;
uint32_t fs;
uint32_t gs;
uint32_t ldt;
uint16_t trap;
uint16_t iomap_base;
} tss_entry;
uint64_t gdt[5];
uint64_t gdt[6];
gdt_ptr_t gdtr;
tss_entry tss;
extern void load_gdt();
extern void tss_flush();
uint64_t create_descriptor(uint32_t base, uint32_t limit, uint16_t flag)
{
@@ -68,6 +101,24 @@ uint64_t create_descriptor(uint32_t base, uint32_t limit, uint16_t flag)
return descriptor;
}
uint64_t create_tss_descriptor(uint32_t base, uint32_t limit)
{
uint64_t descriptor;
uint16_t tss_flags = SEG_PRES(1) | SEG_PRIV(0) | SEG_DESCTYPE(0) | 0x09;
descriptor = limit & 0x000F0000;
descriptor |= (tss_flags << 8) & 0x00F0FF00;
descriptor |= (base >> 16) & 0x000000FF;
descriptor |= base & 0xFF000000;
descriptor <<= 32;
descriptor |= base << 16;
descriptor |= limit & 0x0000FFFF;
return descriptor;
}
void init_gdt() {
gdt[0] = create_descriptor(0, 0, 0);
gdt[1] = create_descriptor(0, 0x000FFFFF, (GDT_CODE_PL0));
@@ -75,9 +126,17 @@ void init_gdt() {
gdt[3] = create_descriptor(0, 0x000FFFFF, (GDT_CODE_PL3));
gdt[4] = create_descriptor(0, 0x000FFFFF, (GDT_DATA_PL3));
gdtr.limit = 5 * sizeof(uint64_t) - 1;
gdtr.base = (uint32_t)&gdt;
for (uint32_t i = 0; i < sizeof(tss_entry); i++) {
((char*)&tss)[i] = 0;
}
tss.ss0 = 0x10;
tss.iomap_base = sizeof(tss_entry);
gdt[5] = create_tss_descriptor((uint32_t)&tss, sizeof(tss_entry) - 1);
gdtr.limit = 6 * sizeof(uint64_t) - 1;
gdtr.base = (uint32_t)&gdt;
load_gdt();
tss_flush();
}