x86, intel_txt: clean up the impact on generic code, unbreak non-x86

Move tboot.h from asm to linux to fix the build errors of intel_txt
patch on non-X86 platforms. Remove the tboot code from generic code
init/main.c and kernel/cpu.c.

Signed-off-by: Shane Wang <shane.wang@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

arch/x86/Kconfig

@@ -178,6 +178,10 @@ config ARCH_SUPPORTS_OPTIMIZED_INLINING
 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
 	def_bool y
 
+config HAVE_INTEL_TXT
+	def_bool y
+	depends on EXPERIMENTAL && DMAR && ACPI
+
 # Use the generic interrupt handling code in kernel/irq/:
 config GENERIC_HARDIRQS
 	bool

arch/x86/kernel/reboot.c

@@ -3,6 +3,7 @@
 #include <linux/init.h>
 #include <linux/pm.h>
 #include <linux/efi.h>
+#include <linux/tboot.h>
 #include <acpi/reboot.h>
 #include <asm/io.h>
 #include <asm/apic.h>
@@ -24,8 +25,6 @@
 # include <asm/iommu.h>
 #endif
 
-#include <asm/tboot.h>
-
 /*
  * Power off function, if any
  */

arch/x86/kernel/setup.c

@@ -66,6 +66,7 @@
 
 #include <linux/percpu.h>
 #include <linux/crash_dump.h>
+#include <linux/tboot.h>
 
 #include <video/edid.h>
 
@@ -145,8 +146,6 @@ struct boot_params __initdata boot_params;
 struct boot_params boot_params;
 #endif
 
-#include <asm/tboot.h>
-
 /*
  * Machine setup..
  */

arch/x86/kernel/smpboot.c

@@ -47,6 +47,7 @@
 #include <linux/bootmem.h>
 #include <linux/err.h>
 #include <linux/nmi.h>
+#include <linux/tboot.h>
 
 #include <asm/acpi.h>
 #include <asm/desc.h>
@@ -62,7 +63,6 @@
 #include <asm/vmi.h>
 #include <asm/apic.h>
 #include <asm/setup.h>
-#include <asm/tboot.h>
 #include <asm/uv/uv.h>
 #include <linux/mc146818rtc.h>
 

arch/x86/kernel/tboot.c

@@ -22,11 +22,14 @@
 #include <linux/dma_remapping.h>
 #include <linux/init_task.h>
 #include <linux/spinlock.h>
+#include <linux/delay.h>
 #include <linux/sched.h>
 #include <linux/init.h>
 #include <linux/dmar.h>
+#include <linux/cpu.h>
 #include <linux/pfn.h>
 #include <linux/mm.h>
+#include <linux/tboot.h>
 
 #include <asm/trampoline.h>
 #include <asm/processor.h>
@@ -36,7 +39,6 @@
 #include <asm/fixmap.h>
 #include <asm/proto.h>
 #include <asm/setup.h>
-#include <asm/tboot.h>
 #include <asm/e820.h>
 #include <asm/io.h>
 
@@ -154,13 +156,10 @@ static int map_tboot_pages(unsigned long vaddr, unsigned long start_pfn,
 	return 0;
 }
 
-void tboot_create_trampoline(void)
+static void tboot_create_trampoline(void)
 {
 	u32 map_base, map_size;
 
-	if (!tboot_enabled())
-		return;
-
 	/* Create identity map for tboot shutdown code. */
 	map_base = PFN_DOWN(tboot->tboot_base);
 	map_size = PFN_UP(tboot->tboot_size);
@@ -295,21 +294,58 @@ void tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control)
 	tboot_shutdown(acpi_shutdown_map[sleep_state]);
 }
 
-int tboot_wait_for_aps(int num_aps)
+static atomic_t ap_wfs_count;
+
+static int tboot_wait_for_aps(int num_aps)
 {
 	unsigned long timeout;
 
+	timeout = AP_WAIT_TIMEOUT*HZ;
+	while (atomic_read((atomic_t *)&tboot->num_in_wfs) != num_aps &&
+	       timeout) {
+		mdelay(1);
+		timeout--;
+	}
+
+	if (timeout)
+		pr_warning("tboot wait for APs timeout\n");
+
+	return !(atomic_read((atomic_t *)&tboot->num_in_wfs) == num_aps);
+}
+
+static int __cpuinit tboot_cpu_callback(struct notifier_block *nfb,
+			unsigned long action, void *hcpu)
+{
+	switch (action) {
+	case CPU_DYING:
+		atomic_inc(&ap_wfs_count);
+		if (num_online_cpus() == 1)
+			if (tboot_wait_for_aps(atomic_read(&ap_wfs_count)))
+				return NOTIFY_BAD;
+		break;
+	}
+	return NOTIFY_OK;
+}
+
+static struct notifier_block tboot_cpu_notifier __cpuinitdata =
+{
+	.notifier_call = tboot_cpu_callback,
+};
+
+static __init int tboot_late_init(void)
+{
 	if (!tboot_enabled())
 		return 0;
 
-	timeout = jiffies + AP_WAIT_TIMEOUT*HZ;
-	while (atomic_read((atomic_t *)&tboot->num_in_wfs) != num_aps &&
-	       time_before(jiffies, timeout))
-		cpu_relax();
+	tboot_create_trampoline();
 
-	return time_before(jiffies, timeout) ? 0 : 1;
+	atomic_set(&ap_wfs_count, 0);
+	register_hotcpu_notifier(&tboot_cpu_notifier);
+	return 0;
 }
 
+late_initcall(tboot_late_init);
+
 /*
  * TXT configuration registers (offsets from TXT_{PUB, PRIV}_CONFIG_REGS_BASE)
  */

drivers/acpi/acpica/hwsleep.c

@@ -45,7 +45,7 @@
 #include <acpi/acpi.h>
 #include "accommon.h"
 #include "actables.h"
-#include <asm/tboot.h>
+#include <linux/tboot.h>
 
 #define _COMPONENT          ACPI_HARDWARE
 ACPI_MODULE_NAME("hwsleep")

drivers/pci/dmar.c

@@ -33,7 +33,7 @@
 #include <linux/timer.h>
 #include <linux/irq.h>
 #include <linux/interrupt.h>
-#include <asm/tboot.h>
+#include <linux/tboot.h>
 
 #undef PREFIX
 #define PREFIX "DMAR:"

drivers/pci/intel-iommu.c

@@ -37,8 +37,8 @@
 #include <linux/iommu.h>
 #include <linux/intel-iommu.h>
 #include <linux/sysdev.h>
+#include <linux/tboot.h>
 #include <asm/cacheflush.h>
-#include <asm/tboot.h>
 #include <asm/iommu.h>
 #include "pci.h"
 

include/linux/tboot.h

@@ -20,10 +20,8 @@
  *
  */
 
-#ifndef _ASM_TBOOT_H
-#define _ASM_TBOOT_H
-
-#include <acpi/acpi.h>
+#ifndef _LINUX_TBOOT_H
+#define _LINUX_TBOOT_H
 
 /* these must have the values from 0-5 in this order */
 enum {
@@ -36,7 +34,7 @@ enum {
 };
 
 #ifdef CONFIG_INTEL_TXT
-
+#include <acpi/acpi.h>
 /* used to communicate between tboot and the launched kernel */
 
 #define TB_KEY_SIZE             64   /* 512 bits */
@@ -144,54 +142,21 @@ static inline int tboot_enabled(void)
 }
 
 extern void tboot_probe(void);
-extern void tboot_create_trampoline(void);
 extern void tboot_shutdown(u32 shutdown_type);
 extern void tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control);
-extern int tboot_wait_for_aps(int num_aps);
 extern struct acpi_table_header *tboot_get_dmar_table(
 				      struct acpi_table_header *dmar_tbl);
 extern int tboot_force_iommu(void);
 
-#else     /* CONFIG_INTEL_TXT */
+#else
 
-static inline int tboot_enabled(void)
-{
-	return 0;
-}
-
-static inline void tboot_probe(void)
-{
-}
-
-static inline void tboot_create_trampoline(void)
-{
-}
-
-static inline void tboot_shutdown(u32 shutdown_type)
-{
-}
-
-static inline void tboot_sleep(u8 sleep_state, u32 pm1a_control,
-			       u32 pm1b_control)
-{
-}
-
-static inline int tboot_wait_for_aps(int num_aps)
-{
-	return 0;
-}
-
-static inline struct acpi_table_header *tboot_get_dmar_table(
-					struct acpi_table_header *dmar_tbl)
-{
-	return dmar_tbl;
-}
-
-static inline int tboot_force_iommu(void)
-{
-	return 0;
-}
+#define tboot_probe()			do { } while (0)
+#define tboot_shutdown(shutdown_type)	do { } while (0)
+#define tboot_sleep(sleep_state, pm1a_control, pm1b_control)	\
+					do { } while (0)
+#define tboot_get_dmar_table(dmar_tbl)	(dmar_tbl)
+#define tboot_force_iommu()		0
 
 #endif /* !CONFIG_INTEL_TXT */
 
-#endif /* _ASM_TBOOT_H */
+#endif /* _LINUX_TBOOT_H */

init/main.c

@@ -73,7 +73,6 @@
 #include <asm/io.h>
 #include <asm/bugs.h>
 #include <asm/setup.h>
-#include <asm/tboot.h>
 #include <asm/sections.h>
 #include <asm/cacheflush.h>
 
@@ -716,8 +715,6 @@ asmlinkage void __init start_kernel(void)
 
 	ftrace_init();
 
-	tboot_create_trampoline();
-
 	/* Do the rest non-__init'ed, we're now alive */
 	rest_init();
 }

kernel/cpu.c

@@ -14,7 +14,6 @@
 #include <linux/kthread.h>
 #include <linux/stop_machine.h>
 #include <linux/mutex.h>
-#include <asm/tboot.h>
 
 #ifdef CONFIG_SMP
 /* Serializes the updates to cpu_online_mask, cpu_present_mask */
@@ -377,7 +376,7 @@ static cpumask_var_t frozen_cpus;
 
 int disable_nonboot_cpus(void)
 {
-	int cpu, first_cpu, error, num_cpus = 0;
+	int cpu, first_cpu, error;
 
 	error = stop_machine_create();
 	if (error)
@@ -392,7 +391,6 @@ int disable_nonboot_cpus(void)
 	for_each_online_cpu(cpu) {
 		if (cpu == first_cpu)
 			continue;
-		num_cpus++;
 		error = _cpu_down(cpu, 1);
 		if (!error) {
 			cpumask_set_cpu(cpu, frozen_cpus);
@@ -403,8 +401,6 @@ int disable_nonboot_cpus(void)
 			break;
 		}
 	}
-	/* ensure all CPUs have gone into wait-for-SIPI */
-	error |= tboot_wait_for_aps(num_cpus);
 
 	if (!error) {
 		BUG_ON(num_online_cpus() > 1);

security/Kconfig

@@ -115,7 +115,7 @@ config SECURITY_ROOTPLUG
 
 config INTEL_TXT
 	bool "Enable Intel(R) Trusted Execution Technology (Intel(R) TXT)"
-	depends on EXPERIMENTAL && X86 && DMAR && ACPI
+	depends on HAVE_INTEL_TXT
 	help
 	  This option enables support for booting the kernel with the
 	  Trusted Boot (tboot) module. This will utilize