drivers/edac: split out functions to unique files

This is a large patch to refactor the original EDAC module in the kernel
and to break it up into better file granularity, such that each source
file contains a given subsystem of the EDAC CORE.

Originally, the EDAC 'core' was contained in one source file: edac_mc.c
with it corresponding edac_mc.h file.

Now, there are the following files:

edac_module.c	The main module init/exit function and other overhead
edac_mc.c	Code handling the edac_mc class of object
edac_mc_sysfs.c	Code handling for sysfs presentation
edac_pci_sysfs.c  Code handling for PCI sysfs presentation
edac_core.h	CORE .h include file for 'edac_mc' and 'edac_device' drivers
edac_module.h	Internal CORE .h include file

This forms a foundation upon which a later patch can create the 'edac_device'
class of object code in a new file 'edac_device.c'.
Signed-off-by: Douglas Thompson <dougthompson@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/edac/Makefile

@@ -8,7 +8,12 @@
 # $Id: Makefile,v 1.4.2.3 2005/07/08 22:05:38 dsp_llnl Exp $
 
 
-obj-$(CONFIG_EDAC_MM_EDAC)		+= edac_mc.o
+obj-$(CONFIG_EDAC_MM_EDAC)		+= edac_core.o
+
+edac_core-objs	:= edac_mc.o edac_mc_sysfs.o edac_pci_sysfs.o
+
+edac_core-objs	+= edac_module.o
+
 obj-$(CONFIG_EDAC_AMD76X)		+= amd76x_edac.o
 obj-$(CONFIG_EDAC_E7XXX)		+= e7xxx_edac.o
 obj-$(CONFIG_EDAC_E752X)		+= e752x_edac.o

drivers/edac/edac_module.c

+
+#include <linux/freezer.h>
+#include <linux/kthread.h>
+
+#include "edac_mc.h"
+#include "edac_module.h"
+
+#define EDAC_MC_VERSION "Ver: 2.0.3" __DATE__
+
+#ifdef CONFIG_EDAC_DEBUG
+/* Values of 0 to 4 will generate output */
+int edac_debug_level = 1;
+EXPORT_SYMBOL_GPL(edac_debug_level);
+#endif
+
+static struct task_struct *edac_thread;
+
+/*
+ * Check MC status every edac_get_poll_msec().
+ * Check PCI status every edac_get_poll_msec() as well.
+ *
+ * This where the work gets done for edac.
+ *
+ * SMP safe, doesn't use NMI, and auto-rate-limits.
+ */
+static void do_edac_check(void)
+{
+	debugf3("%s()\n", __func__);
+
+	/* perform the poll activities */
+	edac_check_mc_devices();
+	edac_pci_do_parity_check();
+}
+
+/*
+ * Action thread for EDAC to perform the POLL operations
+ */
+static int edac_kernel_thread(void *arg)
+{
+	int msec;
+
+	while (!kthread_should_stop()) {
+
+		do_edac_check();
+
+		/* goto sleep for the interval */
+		msec = (HZ * edac_get_poll_msec()) / 1000;
+		schedule_timeout_interruptible(msec);
+		try_to_freeze();
+	}
+
+	return 0;
+}
+
+/*
+ * edac_init
+ *      module initialization entry point
+ */
+static int __init edac_init(void)
+{
+	edac_printk(KERN_INFO, EDAC_MC, EDAC_MC_VERSION "\n");
+
+	/*
+	 * Harvest and clear any boot/initialization PCI parity errors
+	 *
+	 * FIXME: This only clears errors logged by devices present at time of
+	 * 	module initialization.  We should also do an initial clear
+	 *	of each newly hotplugged device.
+	 */
+	edac_pci_clear_parity_errors();
+
+	/* Create the MC sysfs entries */
+	if (edac_sysfs_memctrl_setup()) {
+		edac_printk(KERN_ERR, EDAC_MC,
+			"Error initializing sysfs code\n");
+		return -ENODEV;
+	}
+
+	/* Create the PCI parity sysfs entries */
+	if (edac_sysfs_pci_setup()) {
+		edac_sysfs_memctrl_teardown();
+		edac_printk(KERN_ERR, EDAC_MC,
+			"PCI: Error initializing sysfs code\n");
+		return -ENODEV;
+	}
+
+	/* create our kernel thread */
+	edac_thread = kthread_run(edac_kernel_thread, NULL, "kedac");
+
+	if (IS_ERR(edac_thread)) {
+		/* remove the sysfs entries */
+		edac_sysfs_memctrl_teardown();
+		edac_sysfs_pci_teardown();
+		return PTR_ERR(edac_thread);
+	}
+
+	return 0;
+}
+
+/*
+ * edac_exit()
+ *      module exit/termination function
+ */
+static void __exit edac_exit(void)
+{
+	debugf0("%s()\n", __func__);
+	kthread_stop(edac_thread);
+
+	/* tear down the sysfs device */
+	edac_sysfs_memctrl_teardown();
+	edac_sysfs_pci_teardown();
+}
+
+/*
+ * Inform the kernel of our entry and exit points
+ */
+module_init(edac_init);
+module_exit(edac_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Doug Thompson www.softwarebitmaker.com, et al");
+MODULE_DESCRIPTION("Core library routines for EDAC reporting");
+
+/* refer to *_sysfs.c files for parameters that are exported via sysfs */
+
+#ifdef CONFIG_EDAC_DEBUG
+module_param(edac_debug_level, int, 0644);
+MODULE_PARM_DESC(edac_debug_level, "Debug level");
+#endif
+

drivers/edac/edac_module.h

+
+/*
+ * edac_module.h
+ *
+ * For defining functions/data for within the EDAC_CORE module only
+ *
+ * written by doug thompson <norsk5@xmission.h>
+ */
+
+#ifndef	__EDAC_MODULE_H__
+#define	__EDAC_MODULE_H__
+
+#include <linux/sysdev.h>
+
+#include "edac_core.h"
+
+/*
+ * INTERNAL EDAC MODULE:
+ * EDAC memory controller sysfs create/remove functions
+ * and setup/teardown functions
+ */
+extern int edac_create_sysfs_mci_device(struct mem_ctl_info *mci);
+extern void edac_remove_sysfs_mci_device(struct mem_ctl_info *mci);
+extern int edac_sysfs_memctrl_setup(void);
+extern void edac_sysfs_memctrl_teardown(void);
+extern void edac_check_mc_devices(void);
+extern int edac_get_log_ue(void);
+extern int edac_get_log_ce(void);
+extern int edac_get_panic_on_ue(void);
+extern int edac_get_poll_msec(void);
+
+extern int edac_device_create_sysfs(struct edac_device_ctl_info *edac_dev);
+extern void edac_device_remove_sysfs(struct edac_device_ctl_info *edac_dev);
+extern struct sysdev_class *edac_get_edac_class(void);
+
+
+/*
+ * EDAC PCI functions
+ */
+#ifdef	CONFIG_PCI
+extern void edac_pci_do_parity_check(void);
+extern void edac_pci_clear_parity_errors(void);
+extern int edac_sysfs_pci_setup(void);
+extern void edac_sysfs_pci_teardown(void);
+#else   /* CONFIG_PCI */
+/* pre-process these away */
+#define edac_pci_do_parity_check()
+#define edac_pci_clear_parity_errors()
+#define edac_sysfs_pci_setup()  (0)
+#define edac_sysfs_pci_teardown()
+#endif  /* CONFIG_PCI */
+
+
+#endif	/* __EDAC_MODULE_H__ */
+

drivers/edac/edac_pci_sysfs.c

+/* edac_mc kernel module
+ * (C) 2005, 2006 Linux Networx (http://lnxi.com)
+ * This file may be distributed under the terms of the
+ * GNU General Public License.
+ *
+ * Written Doug Thompson <norsk5@xmission.com>
+ *
+ */
+#include <linux/module.h>
+#include <linux/sysdev.h>
+#include <linux/ctype.h>
+
+#include "edac_mc.h"
+#include "edac_module.h"
+
+
+#ifdef CONFIG_PCI
+static int check_pci_parity = 0;	/* default YES check PCI parity */
+static int panic_on_pci_parity;		/* default no panic on PCI Parity */
+static atomic_t pci_parity_count = ATOMIC_INIT(0);
+
+static struct kobject edac_pci_kobj; /* /sys/devices/system/edac/pci */
+static struct completion edac_pci_kobj_complete;
+
+
+static ssize_t edac_pci_int_show(void *ptr, char *buffer)
+{
+	int *value = ptr;
+	return sprintf(buffer,"%d\n",*value);
+}
+
+static ssize_t edac_pci_int_store(void *ptr, const char *buffer, size_t count)
+{
+	int *value = ptr;
+
+	if (isdigit(*buffer))
+		*value = simple_strtoul(buffer,NULL,0);
+
+	return count;
+}
+
+struct edac_pci_dev_attribute {
+	struct attribute attr;
+	void *value;
+	ssize_t (*show)(void *,char *);
+	ssize_t (*store)(void *, const char *,size_t);
+};
+
+/* Set of show/store abstract level functions for PCI Parity object */
+static ssize_t edac_pci_dev_show(struct kobject *kobj, struct attribute *attr,
+		char *buffer)
+{
+	struct edac_pci_dev_attribute *edac_pci_dev;
+	edac_pci_dev= (struct edac_pci_dev_attribute*)attr;
+
+	if (edac_pci_dev->show)
+		return edac_pci_dev->show(edac_pci_dev->value, buffer);
+	return -EIO;
+}
+
+static ssize_t edac_pci_dev_store(struct kobject *kobj,
+		struct attribute *attr, const char *buffer, size_t count)
+{
+	struct edac_pci_dev_attribute *edac_pci_dev;
+	edac_pci_dev= (struct edac_pci_dev_attribute*)attr;
+
+	if (edac_pci_dev->show)
+		return edac_pci_dev->store(edac_pci_dev->value, buffer, count);
+	return -EIO;
+}
+
+static struct sysfs_ops edac_pci_sysfs_ops = {
+	.show   = edac_pci_dev_show,
+	.store  = edac_pci_dev_store
+};
+
+#define EDAC_PCI_ATTR(_name,_mode,_show,_store)			\
+static struct edac_pci_dev_attribute edac_pci_attr_##_name = {		\
+	.attr = {.name = __stringify(_name), .mode = _mode },	\
+	.value  = &_name,					\
+	.show   = _show,					\
+	.store  = _store,					\
+};
+
+#define EDAC_PCI_STRING_ATTR(_name,_data,_mode,_show,_store)	\
+static struct edac_pci_dev_attribute edac_pci_attr_##_name = {		\
+	.attr = {.name = __stringify(_name), .mode = _mode },	\
+	.value  = _data,					\
+	.show   = _show,					\
+	.store  = _store,					\
+};
+
+/* PCI Parity control files */
+EDAC_PCI_ATTR(check_pci_parity, S_IRUGO|S_IWUSR, edac_pci_int_show,
+	edac_pci_int_store);
+EDAC_PCI_ATTR(panic_on_pci_parity, S_IRUGO|S_IWUSR, edac_pci_int_show,
+	edac_pci_int_store);
+EDAC_PCI_ATTR(pci_parity_count, S_IRUGO, edac_pci_int_show, NULL);
+
+/* Base Attributes of the memory ECC object */
+static struct edac_pci_dev_attribute *edac_pci_attr[] = {
+	&edac_pci_attr_check_pci_parity,
+	&edac_pci_attr_panic_on_pci_parity,
+	&edac_pci_attr_pci_parity_count,
+	NULL,
+};
+
+/* No memory to release */
+static void edac_pci_release(struct kobject *kobj)
+{
+	debugf1("%s()\n", __func__);
+	complete(&edac_pci_kobj_complete);
+}
+
+static struct kobj_type ktype_edac_pci = {
+	.release = edac_pci_release,
+	.sysfs_ops = &edac_pci_sysfs_ops,
+	.default_attrs = (struct attribute **) edac_pci_attr,
+};
+
+/**
+ * edac_sysfs_pci_setup()
+ *
+ *	setup the sysfs for EDAC PCI attributes
+ *	assumes edac_class has already been initialized
+ */
+int edac_sysfs_pci_setup(void)
+{
+	int err;
+	struct sysdev_class *edac_class;
+
+	debugf1("%s()\n", __func__);
+
+	edac_class = edac_get_edac_class();
+
+	memset(&edac_pci_kobj, 0, sizeof(edac_pci_kobj));
+	edac_pci_kobj.parent = &edac_class->kset.kobj;
+	edac_pci_kobj.ktype = &ktype_edac_pci;
+	err = kobject_set_name(&edac_pci_kobj, "pci");
+
+	if (!err) {
+		/* Instanstiate the pci object */
+		/* FIXME: maybe new sysdev_create_subdir() */
+		err = kobject_register(&edac_pci_kobj);
+
+		if (err)
+			debugf1("Failed to register '.../edac/pci'\n");
+		else
+			debugf1("Registered '.../edac/pci' kobject\n");
+	}
+
+	return err;
+}
+
+/*
+ * edac_sysfs_pci_teardown
+ *
+ *	perform the sysfs teardown for the PCI attributes
+ */
+void edac_sysfs_pci_teardown(void)
+{
+	debugf0("%s()\n", __func__);
+	init_completion(&edac_pci_kobj_complete);
+	kobject_unregister(&edac_pci_kobj);
+	wait_for_completion(&edac_pci_kobj_complete);
+}
+
+
+static u16 get_pci_parity_status(struct pci_dev *dev, int secondary)
+{
+	int where;
+	u16 status;
+
+	where = secondary ? PCI_SEC_STATUS : PCI_STATUS;
+	pci_read_config_word(dev, where, &status);
+
+	/* If we get back 0xFFFF then we must suspect that the card has been
+	 * pulled but the Linux PCI layer has not yet finished cleaning up.
+	 * We don't want to report on such devices
+	 */
+
+	if (status == 0xFFFF) {
+		u32 sanity;
+
+		pci_read_config_dword(dev, 0, &sanity);
+
+		if (sanity == 0xFFFFFFFF)
+			return 0;
+	}
+
+	status &= PCI_STATUS_DETECTED_PARITY | PCI_STATUS_SIG_SYSTEM_ERROR |
+		PCI_STATUS_PARITY;
+
+	if (status)
+		/* reset only the bits we are interested in */
+		pci_write_config_word(dev, where, status);
+
+	return status;
+}
+
+typedef void (*pci_parity_check_fn_t) (struct pci_dev *dev);
+
+/* Clear any PCI parity errors logged by this device. */
+static void edac_pci_dev_parity_clear(struct pci_dev *dev)
+{
+	u8 header_type;
+
+	get_pci_parity_status(dev, 0);
+
+	/* read the device TYPE, looking for bridges */
+	pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type);
+
+	if ((header_type & 0x7F) == PCI_HEADER_TYPE_BRIDGE)
+		get_pci_parity_status(dev, 1);
+}
+
+/*
+ *  PCI Parity polling
+ *
+ */
+static void edac_pci_dev_parity_test(struct pci_dev *dev)
+{
+	u16 status;
+	u8  header_type;
+
+	/* read the STATUS register on this device
+	 */
+	status = get_pci_parity_status(dev, 0);
+
+	debugf2("PCI STATUS= 0x%04x %s\n", status, dev->dev.bus_id );
+
+	/* check the status reg for errors */
+	if (status) {
+		if (status & (PCI_STATUS_SIG_SYSTEM_ERROR))
+			edac_printk(KERN_CRIT, EDAC_PCI,
+				"Signaled System Error on %s\n",
+				pci_name(dev));
+
+		if (status & (PCI_STATUS_PARITY)) {
+			edac_printk(KERN_CRIT, EDAC_PCI,
+				"Master Data Parity Error on %s\n",
+				pci_name(dev));
+
+			atomic_inc(&pci_parity_count);
+		}
+
+		if (status & (PCI_STATUS_DETECTED_PARITY)) {
+			edac_printk(KERN_CRIT, EDAC_PCI,
+				"Detected Parity Error on %s\n",
+				pci_name(dev));
+
+			atomic_inc(&pci_parity_count);
+		}
+	}
+
+	/* read the device TYPE, looking for bridges */
+	pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type);
+
+	debugf2("PCI HEADER TYPE= 0x%02x %s\n", header_type, dev->dev.bus_id );
+
+	if ((header_type & 0x7F) == PCI_HEADER_TYPE_BRIDGE) {
+		/* On bridges, need to examine secondary status register  */
+		status = get_pci_parity_status(dev, 1);
+
+		debugf2("PCI SEC_STATUS= 0x%04x %s\n",
+				status, dev->dev.bus_id );
+
+		/* check the secondary status reg for errors */
+		if (status) {
+			if (status & (PCI_STATUS_SIG_SYSTEM_ERROR))
+				edac_printk(KERN_CRIT, EDAC_PCI, "Bridge "
+					"Signaled System Error on %s\n",
+					pci_name(dev));
+
+			if (status & (PCI_STATUS_PARITY)) {
+				edac_printk(KERN_CRIT, EDAC_PCI, "Bridge "
+					"Master Data Parity Error on "
+					"%s\n", pci_name(dev));
+
+				atomic_inc(&pci_parity_count);
+			}
+
+			if (status & (PCI_STATUS_DETECTED_PARITY)) {
+				edac_printk(KERN_CRIT, EDAC_PCI, "Bridge "
+					"Detected Parity Error on %s\n",
+					pci_name(dev));
+
+				atomic_inc(&pci_parity_count);
+			}
+		}
+	}
+}
+
+/*
+ * pci_dev parity list iterator
+ *	Scan the PCI device list for one iteration, looking for SERRORs
+ *	Master Parity ERRORS or Parity ERRORs on primary or secondary devices
+ */
+static inline void edac_pci_dev_parity_iterator(pci_parity_check_fn_t fn)
+{
+	struct pci_dev *dev = NULL;
+
+	/* request for kernel access to the next PCI device, if any,
+	 * and while we are looking at it have its reference count
+	 * bumped until we are done with it
+	 */
+	while((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
+		fn(dev);
+	}
+}
+
+/*
+ * edac_pci_do_parity_check
+ *
+ *	performs the actual PCI parity check operation
+ */
+void edac_pci_do_parity_check(void)
+{
+	unsigned long flags;
+	int before_count;
+
+	debugf3("%s()\n", __func__);
+
+	if (!check_pci_parity)
+		return;
+
+	before_count = atomic_read(&pci_parity_count);
+
+	/* scan all PCI devices looking for a Parity Error on devices and
+	 * bridges
+	 */
+	local_irq_save(flags);
+	edac_pci_dev_parity_iterator(edac_pci_dev_parity_test);
+	local_irq_restore(flags);
+
+	/* Only if operator has selected panic on PCI Error */
+	if (panic_on_pci_parity) {
+		/* If the count is different 'after' from 'before' */
+		if (before_count != atomic_read(&pci_parity_count))
+			panic("EDAC: PCI Parity Error");
+	}
+}
+
+void edac_pci_clear_parity_errors(void)
+{
+	/* Clear any PCI bus parity errors that devices initially have logged
+	 * in their registers.
+	 */
+	edac_pci_dev_parity_iterator(edac_pci_dev_parity_clear);
+}
+
+
+/*
+ * Define the PCI parameter to the module
+ */
+module_param(check_pci_parity, int, 0644);
+MODULE_PARM_DESC(check_pci_parity, "Check for PCI bus parity errors: 0=off 1=on");
+module_param(panic_on_pci_parity, int, 0644);
+MODULE_PARM_DESC(panic_on_pci_parity, "Panic on PCI Bus Parity error: 0=off 1=on");
+
+#endif	/* CONFIG_PCI */