support private mapped file

arch/x86/kernel/cpu.c

@@ -288,8 +288,22 @@ void init_syscall(void)
 	wrmsr(MSR_LSTAR, (unsigned long)x86_syscall);
 }
 
+static void enable_page_protection_fault(void)
+{
+	asm volatile (
+			"pushf	;"
+			"cli	;"
+			"mov	%%cr0,%%rax;"
+			"or	$0x10000,%%rax;"
+			"mov	%%rax,%%cr0;"
+			"popf"
+			::: "%rax");
+	return;
+}
+
 void init_cpu(void)
 {
+	enable_page_protection_fault();
 	init_fpu();
 	init_lapic();
 	init_syscall();
@@ -465,7 +479,7 @@ void cpu_restore_interrupt(unsigned long flags)
 
 void cpu_pause(void)
 {
-	asm volatile("pause");
+	asm volatile("pause" ::: "memory");
 }
 
 unsigned long cpu_disable_interrupt_save(void)

arch/x86/kernel/include/arch-memory.h

@@ -1,6 +1,8 @@
 #ifndef __HEADER_X86_COMMON_ARCH_MEMORY_H
 #define __HEADER_X86_COMMON_ARCH_MEMORY_H
 
+#include <ihk/types.h>
+
 #define KERNEL_CS_ENTRY    4
 #define KERNEL_DS_ENTRY    5
 #define USER_CS_ENTRY      6
@@ -103,9 +105,23 @@ enum ihk_mc_pt_attribute {
 	PTATTR_FOR_USER   = 0x20000,
 };
 
+#define	PTE_NULL ((pte_t)0)
 typedef unsigned long pte_t;
 
-#define	PTE_NULL ((pte_t)0)
+static inline int pte_is_null(pte_t *ptep)
+{
+	return (*ptep == PTE_NULL);
+}
+
+static inline int pte_is_present(pte_t *ptep)
+{
+	return !!(*ptep & PF_PRESENT);
+}
+
+static inline uintptr_t pte_get_phys(pte_t *ptep)
+{
+	return (*ptep & PT_PHYSMASK);
+}
 
 struct page_table;
 void set_pte(pte_t *ppte, unsigned long phys, int attr);

arch/x86/kernel/include/registers.h

@@ -128,6 +128,8 @@ struct x86_regs {
 	unsigned long error, rip, cs, rflags, rsp, ss;
 };
 
+#define	REGS_GET_STACK_POINTER(regs)	(((struct x86_regs *)regs)->rsp)
+
 /*
  * Page fault error code bits:
  *

arch/x86/kernel/memory.c

@@ -7,6 +7,7 @@
 #include <errno.h>
 #include <list.h>
 #include <process.h>
+#include <page.h>
 
 #define	dkprintf(...)
 #define	ekprintf(...)	kprintf(__VA_ARGS__)
@@ -820,16 +821,20 @@ static int clear_range_l1(void *args0, pte_t *ptep, uint64_t base,
 {
 	struct clear_range_args *args = args0;
 	uint64_t phys;
+	struct page *page;
 
 	if (*ptep == PTE_NULL) {
 		return -ENOENT;
 	}
 
 	phys = *ptep & PT_PHYSMASK;
-	*ptep = 0;
+	*ptep = PTE_NULL;
 
 	if (args->free_physical) {
-		ihk_mc_free_pages(phys_to_virt(phys), 1);
+		page = phys_to_page(phys);
+		if (page && page_unmap(page)) {
+			ihk_mc_free_pages(phys_to_virt(phys), 1);
+		}
 	}
 
 	return 0;
@@ -842,6 +847,7 @@ static int clear_range_l2(void *args0, pte_t *ptep, uint64_t base,
 	uint64_t phys;
 	struct page_table *pt;
 	int error;
+	struct page *page;
 
 	if (*ptep == PTE_NULL) {
 		return -ENOENT;
@@ -866,8 +872,10 @@ static int clear_range_l2(void *args0, pte_t *ptep, uint64_t base,
 		*ptep = PTE_NULL;
 
 		if (args->free_physical) {
-			ihk_mc_free_pages(phys_to_virt(phys),
-					LARGE_PAGE_SIZE/PAGE_SIZE);
+			page = phys_to_page(phys);
+			if (page && page_unmap(page)) {
+				ihk_mc_free_pages(phys_to_virt(phys), PTL2_SIZE/PTL1_SIZE);
+			}
 		}
 
 		return 0;