pmap tlb shootdowns

arch/x86_64/idt.c

@@ -3,6 +3,7 @@
 #include <zinnia/irq.h>
 #include <zinnia/panic.h>
 #include <zinnia/percpu.h>
+#include <zinnia/pmap.h>
 #include <zinnia/print.h>
 #include <zinnia/sched.h>
 #include <zinnia/usercopy.h>
@@ -93,6 +94,10 @@ void interrupt_handler(struct arch_context* ctx) {
         if (arch_sched_preempt_enable())
             sched_reschedule(&cpu->sched);
         break;
+    case IDT_IPI_SHOOTDOWN:
+        lapic_eoi(&arch_cpu->lapic);
+        pmap_shootdown_handle();
+        break;
     default:
         if (isr < 0x20)
             panic("Unhandled exception %lu at %#lx, error: %#lx\n", isr, ctx->rip, ctx->error);

arch/x86_64/pmap.c

@@ -1,5 +1,10 @@
+#include <zinnia/irq.h>
+#include <zinnia/percpu.h>
 #include <zinnia/pmap.h>
 #include <zinnia/types.h>
+#include <x86_64/apic.h>
+#include <x86_64/defs.h>
+#include <x86_64/percpu.h>
 #include <x86_64/pmap.h>
 
 void pte_clear(pte_t* pte) {
@@ -10,6 +15,26 @@ void pte_flush(uintptr_t vaddr) {
     asm volatile("invlpg [%0]" ::"r"(vaddr) : "memory");
 }
 
+void pte_flush_all() {
+    uint64_t cr3;
+    asm volatile("mov %0, cr3" : "=r"(cr3));
+    asm volatile("mov cr3, %0" ::"r"(cr3) : "memory");
+}
+
+void pte_shootdown_kick(struct percpu* cpu) {
+    irq_lock();
+    lapic_send_ipi(
+        &percpu_ref(arch_data)->lapic,
+        percpu_ref_on(cpu, arch_data)->lapic.id,
+        IDT_IPI_SHOOTDOWN,
+        APIC_DELIVERY_FIXED,
+        APIC_DEST_PHYSICAL,
+        APIC_LEVEL_ASSERT,
+        APIC_TRIGGER_EDGE
+    );
+    irq_unlock();
+}
+
 pte_t pte_build(phys_t addr, enum pte_flags flags, enum cache_mode cache) {
     pte_t result = ((pte_t)addr & ARCH_PTE_ADDR_MASK) | ARCH_FLAG_PRESENT;
 

arch/x86_64/sched.c

@@ -162,6 +162,7 @@ void arch_task_fini(struct arch_task_context* context) {
     const uintptr_t fpu_base = (uintptr_t)context->fpu_region;
     for (size_t i = 0; i < fpu_size; i += page_size)
         pmap_unmap(&kernel_vma.pmap, fpu_base + i);
+    pmap_shootdown(&kernel_vma.pmap);
     mem_phys_free(context->fpu_phys, ALIGN_UP(fpu_size, page_size) / page_size);
     vm_free(fpu_base, fpu_size);