Max Wash
dbe117135b
the %gs base address is now always set to the current cpu block while in kernel-mode, and is switched back to the userspace %gs base when returning to user-mode.
44 lines
730 B
C
44 lines
730 B
C
#include <arch/gdt.h>
|
|
#include <arch/tss.h>
|
|
#include <kernel/libc/string.h>
|
|
|
|
static void tss_flush(int index)
|
|
{
|
|
index *= sizeof(struct gdt_entry);
|
|
index |= 3;
|
|
asm volatile("mov %0, %%eax; ltr %%ax" ::"r"(index));
|
|
}
|
|
|
|
void tss_init(struct tss *tss, struct tss_ptr *ptr)
|
|
{
|
|
memset(tss, 0x0, sizeof *tss);
|
|
|
|
ptr->tss_base = (uint64_t)tss;
|
|
ptr->tss_limit = (uint16_t)sizeof *tss;
|
|
}
|
|
|
|
void tss_load(struct tss *tss)
|
|
{
|
|
tss_flush(TSS_GDT_INDEX);
|
|
}
|
|
|
|
virt_addr_t tss_get_kstack(struct tss *tss)
|
|
{
|
|
return tss->rsp0;
|
|
}
|
|
|
|
virt_addr_t tss_get_ustack(struct tss *tss)
|
|
{
|
|
return tss->rsp2;
|
|
}
|
|
|
|
void tss_set_kstack(struct tss *tss, virt_addr_t sp)
|
|
{
|
|
tss->rsp0 = sp;
|
|
}
|
|
|
|
void tss_set_ustack(struct tss *tss, virt_addr_t sp)
|
|
{
|
|
tss->rsp2 = sp;
|
|
}
|