/*
* cr3 is the current toplevel pagetable page: the principle is the same as
* cr0. Keep a local copy, and tell the Host when it changes. The only
* difference is that our local copy is in lguest_data because the Host needs
* to set it upon our initial hypercall.
*/
static void lguest_write_cr3(unsigned long cr3)
{
lguest_data.pgdir = cr3;
lazy_hcall1(LHCALL_NEW_PGTABLE, cr3);
/* These two page tables are simple, linear, and used during boot */
if (cr3 != __pa(swapper_pg_dir) && cr3 != __pa(initial_page_table))
cr3_changed = true;
}
static void lguest_flush_tlb_kernel(void)
{
lazy_hcall1(LHCALL_FLUSH_TLB, 1);
}
static void lguest_flush_tlb_user(void)
{
lazy_hcall1(LHCALL_FLUSH_TLB, 0);
}
static void lguest_set_pte_atomic(pte_t *ptep, pte_t pte)
{
native_set_pte_atomic(ptep, pte);
if (cr3_changed)
lazy_hcall1(LHCALL_FLUSH_TLB, 1);
}
static void lguest_write_cr3(unsigned long cr3)
{
lguest_data.pgdir = cr3;
lazy_hcall1(LHCALL_NEW_PGTABLE, cr3);
cr3_changed = true;
}
static void lguest_clts(void)
{
lazy_hcall1(LHCALL_TS, 0);
current_cr0 &= ~X86_CR0_TS;
}
static void lguest_write_cr0(unsigned long val)
{
lazy_hcall1(LHCALL_TS, val & X86_CR0_TS);
current_cr0 = val;
}
/* There are a couple of legacy places where the kernel sets a PTE, but we
* don't know the top level any more. This is useless for us, since we don't
* know which pagetable is changing or what address, so we just tell the Host
* to forget all of them. Fortunately, this is very rare.
*
* ... except in early boot when the kernel sets up the initial pagetables,
* which makes booting astonishingly slow: 1.83 seconds! So we don't even tell
* the Host anything changed until we've done the first page table switch,
* which brings boot back to 0.25 seconds. */
static void lguest_set_pte(pte_t *ptep, pte_t pteval)
{
*ptep = pteval;
if (cr3_changed)
lazy_hcall1(LHCALL_FLUSH_TLB, 1);
}