assada/os
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

fix userspace?

Browse Source
This commit is contained in:
assada
2025-01-31 16:38:38 +01:00
parent ad929efeb2
commit 79a4f79a24
7 changed files with 149 additions and 62 deletions
Download Patch File Download Diff File Expand all files Collapse all files

38
gdt.c
View File

@@ -25,39 +25,45 @@ static void gdt_set_gate(uint8_t num, uint32_t base, uint32_t limit, uint8_t acc
gdt[num].access = access;
}
static void tss_install(uint8_t num, uint16_t kernel_ss, uint16_t kernel_esp)
void tss_install(uint8_t num, uint16_t kernel_ss, uint16_t kernel_esp)
{
uint32_t base = (uint32_t)&tss;
uint32_t limit = base + sizeof(Tss_entry);
gdt_set_gate(num, base, limit, 0xE9, 0x0);
uint32_t limit = sizeof(Tss_entry);
memset(&tss, 0, sizeof(Tss_entry));
tss.ss0 = kernel_ss;
tss.esp0 = kernel_esp + 0x1000; // SHIT
tss.cs = 0x1B;
tss.esp0 = kernel_esp;
tss.cs = 0x1b;
tss.ss = 0x23;
tss.es = 0x23;
tss.ds = 0x23;
tss.es = 0x23;
tss.fs = 0x23;
tss.gs = 0x23;
tss.iopb_off = sizeof(Tss_entry);
gdt_set_gate(num, base, limit, I86_GDT_DESC_ACCESS | I86_GDT_DESC_EXEC_CODE | I86_GDT_DESC_DPL | I86_GDT_DESC_MEMORY, 0x00);
}
void gdt_install()
{
gdt_set_gate(0, 0x0, 0x0, 0x0, 0x0); // Null segment
gdt_set_gate(1, 0x0, 0xFFFFFFFF, 0x9A, 0xCF); // 0x08 Kernel code segment
gdt_set_gate(2, 0x0, 0xFFFFFFFF, 0x92, 0xCF); // 0x10 Kernel Data segment
gdt_set_gate(3, 0x0, 0xFFFFFFFF, 0xFA, 0xCF); // 0x18 User code segment
gdt_set_gate(4, 0x0, 0xFFFFFFFF, 0xF2, 0xCF); // 0x20 User data segment
tss_install(5, 0x10, stack_top);
gdtp.limit = (sizeof(Gdt_entry) * GDT_ENTRY) - 1;
gdtp.base = (uint32_t)&gdt;
gdt_set_gate(0, 0, 0, 0, 0);
gdt_set_gate(1, 0, 0xFFFFFFFF, 0x9A, 0xCF);
gdt_set_gate(2, 0, 0xFFFFFFFF, 0x92, 0xCF);
gdt_set_gate(3, 0, 0xFFFFFFFF, 0xFA, 0xCF);
gdt_set_gate(4, 0, 0xFFFFFFFF, 0xF2, 0xCF);
tss_install(5, 0x10, (uint32_t)&stack_top);
gdt_flush((uint32_t)&gdtp);
tss_flush();
}