1 files changed, 343 insertions, 88 deletions

diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index 0d505e5..d1d484d 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -12,10 +12,6 @@
  * For more information about Generic Hardware Error Source, please
  * refer to ACPI Specification version 4.0, section 17.3.2.6
  *
- * Now, only SCI notification type and memory errors are
- * supported. More notification type and hardware error type will be
- * added later.
- *
  * Copyright 2010 Intel Corp.
  *   Author: Huang Ying <ying.huang@intel.com>
  *
@@ -39,14 +35,18 @@
 #include <linux/acpi.h>
 #include <linux/io.h>
 #include <linux/interrupt.h>
+#include <linux/timer.h>
 #include <linux/cper.h>
 #include <linux/kdebug.h>
 #include <linux/platform_device.h>
 #include <linux/mutex.h>
+#include <linux/ratelimit.h>
+#include <linux/vmalloc.h>
 #include <acpi/apei.h>
 #include <acpi/atomicio.h>
 #include <acpi/hed.h>
 #include <asm/mce.h>
+#include <asm/tlbflush.h>
 
 #include "apei-internal.h"
 
@@ -55,42 +55,131 @@
 #define GHES_ESTATUS_MAX_SIZE		65536
 
 /*
- * One struct ghes is created for each generic hardware error
- * source.
- *
+ * One struct ghes is created for each generic hardware error source.
  * It provides the context for APEI hardware error timer/IRQ/SCI/NMI
- * handler. Handler for one generic hardware error source is only
- * triggered after the previous one is done. So handler can uses
- * struct ghes without locking.
+ * handler.
  *
  * estatus: memory buffer for error status block, allocated during
  * HEST parsing.
  */
 #define GHES_TO_CLEAR		0x0001
+#define GHES_EXITING		0x0002
 
 struct ghes {
 	struct acpi_hest_generic *generic;
 	struct acpi_hest_generic_status *estatus;
-	struct list_head list;
 	u64 buffer_paddr;
 	unsigned long flags;
+	union {
+		struct list_head list;
+		struct timer_list timer;
+		unsigned int irq;
+	};
 };
 
+static int ghes_panic_timeout	__read_mostly = 30;
+
 /*
- * Error source lists, one list for each notification method. The
- * members in lists are struct ghes.
+ * All error sources notified with SCI shares one notifier function,
+ * so they need to be linked and checked one by one.  This is applied
+ * to NMI too.
  *
- * The list members are only added in HEST parsing and deleted during
- * module_exit, that is, single-threaded. So no lock is needed for
- * that.
- *
- * But the mutual exclusion is needed between members adding/deleting
- * and timer/IRQ/SCI/NMI handler, which may traverse the list. RCU is
- * used for that.
+ * RCU is used for these lists, so ghes_list_mutex is only used for
+ * list changing, not for traversing.
  */
 static LIST_HEAD(ghes_sci);
+static LIST_HEAD(ghes_nmi);
 static DEFINE_MUTEX(ghes_list_mutex);
 
+/*
+ * NMI may be triggered on any CPU, so ghes_nmi_lock is used for
+ * mutual exclusion.
+ */
+static DEFINE_RAW_SPINLOCK(ghes_nmi_lock);
+
+/*
+ * Because the memory area used to transfer hardware error information
+ * from BIOS to Linux can be determined only in NMI, IRQ or timer
+ * handler, but general ioremap can not be used in atomic context, so
+ * a special version of atomic ioremap is implemented for that.
+ */
+
+/*
+ * Two virtual pages are used, one for NMI context, the other for
+ * IRQ/PROCESS context
+ */
+#define GHES_IOREMAP_PAGES		2
+#define GHES_IOREMAP_NMI_PAGE(base)	(base)
+#define GHES_IOREMAP_IRQ_PAGE(base)	((base) + PAGE_SIZE)
+
+/* virtual memory area for atomic ioremap */
+static struct vm_struct *ghes_ioremap_area;
+/*
+ * These 2 spinlock is used to prevent atomic ioremap virtual memory
+ * area from being mapped simultaneously.
+ */
+static DEFINE_RAW_SPINLOCK(ghes_ioremap_lock_nmi);
+static DEFINE_SPINLOCK(ghes_ioremap_lock_irq);
+
+static int ghes_ioremap_init(void)
+{
+	ghes_ioremap_area = __get_vm_area(PAGE_SIZE * GHES_IOREMAP_PAGES,
+		VM_IOREMAP, VMALLOC_START, VMALLOC_END);
+	if (!ghes_ioremap_area) {
+		pr_err(GHES_PFX "Failed to allocate virtual memory area for atomic ioremap.\n");
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void ghes_ioremap_exit(void)
+{
+	free_vm_area(ghes_ioremap_area);
+}
+
+static void __iomem *ghes_ioremap_pfn_nmi(u64 pfn)
+{
+	unsigned long vaddr;
+
+	vaddr = (unsigned long)GHES_IOREMAP_NMI_PAGE(ghes_ioremap_area->addr);
+	ioremap_page_range(vaddr, vaddr + PAGE_SIZE,
+			   pfn << PAGE_SHIFT, PAGE_KERNEL);
+
+	return (void __iomem *)vaddr;
+}
+
+static void __iomem *ghes_ioremap_pfn_irq(u64 pfn)
+{
+	unsigned long vaddr;
+
+	vaddr = (unsigned long)GHES_IOREMAP_IRQ_PAGE(ghes_ioremap_area->addr);
+	ioremap_page_range(vaddr, vaddr + PAGE_SIZE,
+			   pfn << PAGE_SHIFT, PAGE_KERNEL);
+
+	return (void __iomem *)vaddr;
+}
+
+static void ghes_iounmap_nmi(void __iomem *vaddr_ptr)
+{
+	unsigned long vaddr = (unsigned long __force)vaddr_ptr;
+	void *base = ghes_ioremap_area->addr;
+
+	BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_NMI_PAGE(base));
+	unmap_kernel_range_noflush(vaddr, PAGE_SIZE);
+	__flush_tlb_one(vaddr);
+}
+
+static void ghes_iounmap_irq(void __iomem *vaddr_ptr)
+{
+	unsigned long vaddr = (unsigned long __force)vaddr_ptr;
+	void *base = ghes_ioremap_area->addr;
+
+	BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_IRQ_PAGE(base));
+	unmap_kernel_range_noflush(vaddr, PAGE_SIZE);
+	__flush_tlb_one(vaddr);
+}
+
 static struct ghes *ghes_new(struct acpi_hest_generic *generic)
 {
 	struct ghes *ghes;
@@ -101,7 +190,6 @@ static struct ghes *ghes_new(struct acpi_hest_generic *generic)
 	if (!ghes)
 		return ERR_PTR(-ENOMEM);
 	ghes->generic = generic;
-	INIT_LIST_HEAD(&ghes->list);
 	rc = acpi_pre_map_gar(&generic->error_status_address);
 	if (rc)
 		goto err_free;
@@ -158,22 +246,41 @@ static inline int ghes_severity(int severity)
 	}
 }
 
-/* SCI handler run in work queue, so ioremap can be used here */
-static int ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len,
-				 int from_phys)
+static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len,
+				  int from_phys)
 {
-	void *vaddr;
-
-	vaddr = ioremap_cache(paddr, len);
-	if (!vaddr)
-		return -ENOMEM;
-	if (from_phys)
-		memcpy(buffer, vaddr, len);
-	else
-		memcpy(vaddr, buffer, len);
-	iounmap(vaddr);
-
-	return 0;
+	void __iomem *vaddr;
+	unsigned long flags = 0;
+	int in_nmi = in_nmi();
+	u64 offset;
+	u32 trunk;
+
+	while (len > 0) {
+		offset = paddr - (paddr & PAGE_MASK);
+		if (in_nmi) {
+			raw_spin_lock(&ghes_ioremap_lock_nmi);
+			vaddr = ghes_ioremap_pfn_nmi(paddr >> PAGE_SHIFT);
+		} else {
+			spin_lock_irqsave(&ghes_ioremap_lock_irq, flags);
+			vaddr = ghes_ioremap_pfn_irq(paddr >> PAGE_SHIFT);
+		}
+		trunk = PAGE_SIZE - offset;
+		trunk = min(trunk, len);
+		if (from_phys)
+			memcpy_fromio(buffer, vaddr + offset, trunk);
+		else
+			memcpy_toio(vaddr + offset, buffer, trunk);
+		len -= trunk;
+		paddr += trunk;
+		buffer += trunk;
+		if (in_nmi) {
+			ghes_iounmap_nmi(vaddr);
+			raw_spin_unlock(&ghes_ioremap_lock_nmi);
+		} else {
+			ghes_iounmap_irq(vaddr);
+			spin_unlock_irqrestore(&ghes_ioremap_lock_irq, flags);
+		}
+	}
 }
 
 static int ghes_read_estatus(struct ghes *ghes, int silent)
@@ -194,10 +301,8 @@ static int ghes_read_estatus(struct ghes *ghes, int silent)
 	if (!buf_paddr)
 		return -ENOENT;
 
-	rc = ghes_copy_tofrom_phys(ghes->estatus, buf_paddr,
-				   sizeof(*ghes->estatus), 1);
-	if (rc)
-		return rc;
+	ghes_copy_tofrom_phys(ghes->estatus, buf_paddr,
+			      sizeof(*ghes->estatus), 1);
 	if (!ghes->estatus->block_status)
 		return -ENOENT;
 
@@ -212,17 +317,15 @@ static int ghes_read_estatus(struct ghes *ghes, int silent)
 		goto err_read_block;
 	if (apei_estatus_check_header(ghes->estatus))
 		goto err_read_block;
-	rc = ghes_copy_tofrom_phys(ghes->estatus + 1,
-				   buf_paddr + sizeof(*ghes->estatus),
-				   len - sizeof(*ghes->estatus), 1);
-	if (rc)
-		return rc;
+	ghes_copy_tofrom_phys(ghes->estatus + 1,
+			      buf_paddr + sizeof(*ghes->estatus),
+			      len - sizeof(*ghes->estatus), 1);
 	if (apei_estatus_check(ghes->estatus))
 		goto err_read_block;
 	rc = 0;
 
 err_read_block:
-	if (rc && !silent)
+	if (rc && !silent && printk_ratelimit())
 		pr_warning(FW_WARN GHES_PFX
 			   "Failed to read error status block!\n");
 	return rc;
@@ -255,11 +358,26 @@ static void ghes_do_proc(struct ghes *ghes)
 		}
 #endif
 	}
+}
 
-	if (!processed && printk_ratelimit())
-		pr_warning(GHES_PFX
-		"Unknown error record from generic hardware error source: %d\n",
-			   ghes->generic->header.source_id);
+static void ghes_print_estatus(const char *pfx, struct ghes *ghes)
+{
+	/* Not more than 2 messages every 5 seconds */
+	static DEFINE_RATELIMIT_STATE(ratelimit, 5*HZ, 2);
+
+	if (pfx == NULL) {
+		if (ghes_severity(ghes->estatus->error_severity) <=
+		    GHES_SEV_CORRECTED)
+			pfx = KERN_WARNING HW_ERR;
+		else
+			pfx = KERN_ERR HW_ERR;
+	}
+	if (__ratelimit(&ratelimit)) {
+		printk(
+	"%s""Hardware error from APEI Generic Hardware Error Source: %d\n",
+	pfx, ghes->generic->header.source_id);
+		apei_estatus_print(pfx, ghes->estatus);
+	}
 }
 
 static int ghes_proc(struct ghes *ghes)
@@ -269,6 +387,7 @@ static int ghes_proc(struct ghes *ghes)
 	rc = ghes_read_estatus(ghes, 0);
 	if (rc)
 		goto out;
+	ghes_print_estatus(NULL, ghes);
 	ghes_do_proc(ghes);
 
 out:
@@ -276,6 +395,42 @@ out:
 	return 0;
 }
 
+static void ghes_add_timer(struct ghes *ghes)
+{
+	struct acpi_hest_generic *g = ghes->generic;
+	unsigned long expire;
+
+	if (!g->notify.poll_interval) {
+		pr_warning(FW_WARN GHES_PFX "Poll interval is 0 for generic hardware error source: %d, disabled.\n",
+			   g->header.source_id);
+		return;
+	}
+	expire = jiffies + msecs_to_jiffies(g->notify.poll_interval);
+	ghes->timer.expires = round_jiffies_relative(expire);
+	add_timer(&ghes->timer);
+}
+
+static void ghes_poll_func(unsigned long data)
+{
+	struct ghes *ghes = (void *)data;
+
+	ghes_proc(ghes);
+	if (!(ghes->flags & GHES_EXITING))
+		ghes_add_timer(ghes);
+}
+
+static irqreturn_t ghes_irq_func(int irq, void *data)
+{
+	struct ghes *ghes = data;
+	int rc;
+
+	rc = ghes_proc(ghes);
+	if (rc)
+		return IRQ_NONE;
+
+	return IRQ_HANDLED;
+}
+
 static int ghes_notify_sci(struct notifier_block *this,
 				  unsigned long event, void *data)
 {
@@ -292,10 +447,63 @@ static int ghes_notify_sci(struct notifier_block *this,
 	return ret;
 }
 
+static int ghes_notify_nmi(struct notifier_block *this,
+				  unsigned long cmd, void *data)
+{
+	struct ghes *ghes, *ghes_global = NULL;
+	int sev, sev_global = -1;
+	int ret = NOTIFY_DONE;
+
+	if (cmd != DIE_NMI)
+		return ret;
+
+	raw_spin_lock(&ghes_nmi_lock);
+	list_for_each_entry_rcu(ghes, &ghes_nmi, list) {
+		if (ghes_read_estatus(ghes, 1)) {
+			ghes_clear_estatus(ghes);
+			continue;
+		}
+		sev = ghes_severity(ghes->estatus->error_severity);
+		if (sev > sev_global) {
+			sev_global = sev;
+			ghes_global = ghes;
+		}
+		ret = NOTIFY_STOP;
+	}
+
+	if (ret == NOTIFY_DONE)
+		goto out;
+
+	if (sev_global >= GHES_SEV_PANIC) {
+		oops_begin();
+		ghes_print_estatus(KERN_EMERG HW_ERR, ghes_global);
+		/* reboot to log the error! */
+		if (panic_timeout == 0)
+			panic_timeout = ghes_panic_timeout;
+		panic("Fatal hardware error!");
+	}
+
+	list_for_each_entry_rcu(ghes, &ghes_nmi, list) {
+		if (!(ghes->flags & GHES_TO_CLEAR))
+			continue;
+		/* Do not print estatus because printk is not NMI safe */
+		ghes_do_proc(ghes);
+		ghes_clear_estatus(ghes);
+	}
+
+out:
+	raw_spin_unlock(&ghes_nmi_lock);
+	return ret;
+}
+
 static struct notifier_block ghes_notifier_sci = {
 	.notifier_call = ghes_notify_sci,
 };
 
+static struct notifier_block ghes_notifier_nmi = {
+	.notifier_call = ghes_notify_nmi,
+};
+
 static int __devinit ghes_probe(struct platform_device *ghes_dev)
 {
 	struct acpi_hest_generic *generic;
@@ -306,18 +514,27 @@ static int __devinit ghes_probe(struct platform_device *ghes_dev)
 	if (!generic->enabled)
 		return -ENODEV;
 
-	if (generic->error_block_length <
-	    sizeof(struct acpi_hest_generic_status)) {
-		pr_warning(FW_BUG GHES_PFX
-"Invalid error block length: %u for generic hardware error source: %d\n",
-			   generic->error_block_length,
+	switch (generic->notify.type) {
+	case ACPI_HEST_NOTIFY_POLLED:
+	case ACPI_HEST_NOTIFY_EXTERNAL:
+	case ACPI_HEST_NOTIFY_SCI:
+	case ACPI_HEST_NOTIFY_NMI:
+		break;
+	case ACPI_HEST_NOTIFY_LOCAL:
+		pr_warning(GHES_PFX "Generic hardware error source: %d notified via local interrupt is not supported!\n",
 			   generic->header.source_id);
 		goto err;
+	default:
+		pr_warning(FW_WARN GHES_PFX "Unknown notification type: %u for generic hardware error source: %d\n",
+			   generic->notify.type, generic->header.source_id);
+		goto err;
 	}
-	if (generic->records_to_preallocate == 0) {
-		pr_warning(FW_BUG GHES_PFX
-"Invalid records to preallocate: %u for generic hardware error source: %d\n",
-			   generic->records_to_preallocate,
+
+	rc = -EIO;
+	if (generic->error_block_length <
+	    sizeof(struct acpi_hest_generic_status)) {
+		pr_warning(FW_BUG GHES_PFX "Invalid error block length: %u for generic hardware error source: %d\n",
+			   generic->error_block_length,
 			   generic->header.source_id);
 		goto err;
 	}
@@ -327,38 +544,43 @@ static int __devinit ghes_probe(struct platform_device *ghes_dev)
 		ghes = NULL;
 		goto err;
 	}
-	if (generic->notify.type == ACPI_HEST_NOTIFY_SCI) {
+	switch (generic->notify.type) {
+	case ACPI_HEST_NOTIFY_POLLED:
+		ghes->timer.function = ghes_poll_func;
+		ghes->timer.data = (unsigned long)ghes;
+		init_timer_deferrable(&ghes->timer);
+		ghes_add_timer(ghes);
+		break;
+	case ACPI_HEST_NOTIFY_EXTERNAL:
+		/* External interrupt vector is GSI */
+		if (acpi_gsi_to_irq(generic->notify.vector, &ghes->irq)) {
+			pr_err(GHES_PFX "Failed to map GSI to IRQ for generic hardware error source: %d\n",
+			       generic->header.source_id);
+			goto err;
+		}
+		if (request_irq(ghes->irq, ghes_irq_func,
+				0, "GHES IRQ", ghes)) {
+			pr_err(GHES_PFX "Failed to register IRQ for generic hardware error source: %d\n",
+			       generic->header.source_id);
+			goto err;
+		}
+		break;
+	case ACPI_HEST_NOTIFY_SCI:
 		mutex_lock(&ghes_list_mutex);
 		if (list_empty(&ghes_sci))
 			register_acpi_hed_notifier(&ghes_notifier_sci);
 		list_add_rcu(&ghes->list, &ghes_sci);
 		mutex_unlock(&ghes_list_mutex);
-	} else {
-		unsigned char *notify = NULL;
-
-		switch (generic->notify.type) {
-		case ACPI_HEST_NOTIFY_POLLED:
-			notify = "POLL";
-			break;
-		case ACPI_HEST_NOTIFY_EXTERNAL:
-		case ACPI_HEST_NOTIFY_LOCAL:
-			notify = "IRQ";
-			break;
-		case ACPI_HEST_NOTIFY_NMI:
-			notify = "NMI";
-			break;
-		}
-		if (notify) {
-			pr_warning(GHES_PFX
-"Generic hardware error source: %d notified via %s is not supported!\n",
-				   generic->header.source_id, notify);
-		} else {
-			pr_warning(FW_WARN GHES_PFX
-"Unknown notification type: %u for generic hardware error source: %d\n",
-			generic->notify.type, generic->header.source_id);
-		}
-		rc = -ENODEV;
-		goto err;
+		break;
+	case ACPI_HEST_NOTIFY_NMI:
+		mutex_lock(&ghes_list_mutex);
+		if (list_empty(&ghes_nmi))
+			register_die_notifier(&ghes_notifier_nmi);
+		list_add_rcu(&ghes->list, &ghes_nmi);
+		mutex_unlock(&ghes_list_mutex);
+		break;
+	default:
+		BUG();
 	}
 	platform_set_drvdata(ghes_dev, ghes);
 
@@ -379,7 +601,14 @@ static int __devexit ghes_remove(struct platform_device *ghes_dev)
 	ghes = platform_get_drvdata(ghes_dev);
 	generic = ghes->generic;
 
+	ghes->flags |= GHES_EXITING;
 	switch (generic->notify.type) {
+	case ACPI_HEST_NOTIFY_POLLED:
+		del_timer_sync(&ghes->timer);
+		break;
+	case ACPI_HEST_NOTIFY_EXTERNAL:
+		free_irq(ghes->irq, ghes);
+		break;
 	case ACPI_HEST_NOTIFY_SCI:
 		mutex_lock(&ghes_list_mutex);
 		list_del_rcu(&ghes->list);
@@ -387,12 +616,23 @@ static int __devexit ghes_remove(struct platform_device *ghes_dev)
 			unregister_acpi_hed_notifier(&ghes_notifier_sci);
 		mutex_unlock(&ghes_list_mutex);
 		break;
+	case ACPI_HEST_NOTIFY_NMI:
+		mutex_lock(&ghes_list_mutex);
+		list_del_rcu(&ghes->list);
+		if (list_empty(&ghes_nmi))
+			unregister_die_notifier(&ghes_notifier_nmi);
+		mutex_unlock(&ghes_list_mutex);
+		/*
+		 * To synchronize with NMI handler, ghes can only be
+		 * freed after NMI handler finishes.
+		 */
+		synchronize_rcu();
+		break;
 	default:
 		BUG();
 		break;
 	}
 
-	synchronize_rcu();
 	ghes_fini(ghes);
 	kfree(ghes);
 
@@ -412,6 +652,8 @@ static struct platform_driver ghes_platform_driver = {
 
 static int __init ghes_init(void)
 {
+	int rc;
+
 	if (acpi_disabled)
 		return -ENODEV;
 
@@ -420,12 +662,25 @@ static int __init ghes_init(void)
 		return -EINVAL;
 	}
 
-	return platform_driver_register(&ghes_platform_driver);
+	rc = ghes_ioremap_init();
+	if (rc)
+		goto err;
+
+	rc = platform_driver_register(&ghes_platform_driver);
+	if (rc)
+		goto err_ioremap_exit;
+
+	return 0;
+err_ioremap_exit:
+	ghes_ioremap_exit();
+err:
+	return rc;
 }
 
 static void __exit ghes_exit(void)
 {
 	platform_driver_unregister(&ghes_platform_driver);
+	ghes_ioremap_exit();
 }
 
 module_init(ghes_init);