patch-2.4.22 linux-2.4.22/arch/ia64/kernel/salinfo.c

• Lines: 360
• Date: 2003-08-25 04:44:39.000000000 -0700
• Orig file: linux-2.4.21/arch/ia64/kernel/salinfo.c
• Orig date: 2002-11-28 15:53:09.000000000 -0800

diff -urN linux-2.4.21/arch/ia64/kernel/salinfo.c linux-2.4.22/arch/ia64/kernel/salinfo.c
@@ -4,6 +4,8 @@
  * Creates entries in /proc/sal for various system features.
  *
  * Copyright (c) 2001 Silicon Graphics, Inc.  All rights reserved.
+ * Copyright (c) 2003 Hewlett-Packard Co
+ *	Bjorn Helgaas <bjorn.helgaas@hp.com>
  *
  * 10/30/2001	jbarnes@sgi.com		copied much of Stephane's palinfo
  *					code to create this file
@@ -12,8 +14,10 @@
 #include <linux/types.h>
 #include <linux/proc_fs.h>
 #include <linux/module.h>
+#include <linux/smp.h>
 
 #include <asm/sal.h>
+#include <asm/uaccess.h>
 
 MODULE_AUTHOR("Jesse Barnes <jbarnes@sgi.com>");
 MODULE_DESCRIPTION("/proc interface to IA-64 SAL features");
@@ -40,25 +44,325 @@
 
 #define NR_SALINFO_ENTRIES (sizeof(salinfo_entries)/sizeof(salinfo_entry_t))
 
-/*
- * One for each feature and one more for the directory entry...
- */
-static struct proc_dir_entry *salinfo_proc_entries[NR_SALINFO_ENTRIES + 1];
+static char *salinfo_log_name[] = {
+	"mca",
+	"init",
+	"cmc",
+	"cpe",
+};
+
+static struct proc_dir_entry *salinfo_proc_entries[
+	ARRAY_SIZE(salinfo_entries) +			/* /proc/sal/bus_lock */
+	ARRAY_SIZE(salinfo_log_name) +			/* /proc/sal/{mca,...} */
+	(2 * ARRAY_SIZE(salinfo_log_name)) +		/* /proc/sal/mca/{event,data} */
+	1];						/* /proc/sal */
+
+struct salinfo_log_data {
+	int	type;
+	u8	*log_buffer;
+	u64	log_size;
+};
+
+struct salinfo_event {
+	int			type;
+	int			cpu;		/* next CPU to check */
+	volatile unsigned long	cpu_mask;
+	wait_queue_head_t	queue;
+};
+
+static struct salinfo_event *salinfo_event[ARRAY_SIZE(salinfo_log_name)];
+
+struct salinfo_data {
+	int	open;		/* single-open to prevent races */
+	int	type;
+	int	cpu;		/* "current" cpu for reads */
+};
+
+static struct salinfo_data salinfo_data[ARRAY_SIZE(salinfo_log_name)];
+
+static spinlock_t data_lock;
+
+void
+salinfo_log_wakeup(int type)
+{
+	if (type < ARRAY_SIZE(salinfo_log_name)) {
+		struct salinfo_event *event = salinfo_event[type];
+
+		if (event) {
+			set_bit(smp_processor_id(), &event->cpu_mask);
+			wake_up_interruptible(&event->queue);
+		}
+	}
+}
+
+static int
+salinfo_event_open(struct inode *inode, struct file *file)
+{
+	struct proc_dir_entry *entry = (struct proc_dir_entry *) inode->u.generic_ip;
+	struct salinfo_event *event = entry->data;
+
+	if (!suser())
+		return -EPERM;
+	return 0;
+}
+
+static ssize_t
+salinfo_event_read(struct file *file, char *buffer, size_t count, loff_t *ppos)
+{
+	struct inode *inode = file->f_dentry->d_inode;
+	struct proc_dir_entry *entry = (struct proc_dir_entry *) inode->u.generic_ip;
+	struct salinfo_event *event = entry->data;
+	char cmd[32];
+	size_t size;
+	int i, n, cpu = -1;
+
+retry:
+	if (!event->cpu_mask) {
+		if (file->f_flags & O_NONBLOCK)
+			return -EAGAIN;
+		interruptible_sleep_on(&event->queue);
+		if (signal_pending(current))
+			return -EINTR;
+	}
+
+	n = event->cpu;
+	for (i = 0; i < NR_CPUS; i++) {
+		if (event->cpu_mask & 1UL << n) {
+			cpu = n;
+			break;
+		}
+		if (++n == NR_CPUS)
+			n = 0;
+	}
+
+	if (cpu == -1)
+		goto retry;
+
+	/* for next read, start checking at next CPU */
+	event->cpu = cpu;
+	if (++event->cpu == NR_CPUS)
+		event->cpu = 0;
+
+	snprintf(cmd, sizeof(cmd), "read %d\n", cpu);
+
+	size = strlen(cmd);
+	if (size > count)
+		size = count;
+	if (copy_to_user(buffer, cmd, size))
+		return -EFAULT;
+
+	return size;
+}
+
+static struct file_operations salinfo_event_fops = {
+	.open  = salinfo_event_open,
+	.read  = salinfo_event_read,
+};
+
+static int
+salinfo_log_open(struct inode *inode, struct file *file)
+{
+	struct proc_dir_entry *entry = (struct proc_dir_entry *) inode->u.generic_ip;
+	struct salinfo_data *data = entry->data;
+
+	if (!suser())
+		return -EPERM;
+
+	spin_lock(&data_lock);
+	if (data->open) {
+		spin_unlock(&data_lock);
+		return -EBUSY;
+	}
+	data->open = 1;
+	spin_unlock(&data_lock);
+
+	return 0;
+}
+
+static int
+salinfo_log_release(struct inode *inode, struct file *file)
+{
+	struct proc_dir_entry *entry = (struct proc_dir_entry *) inode->u.generic_ip;
+	struct salinfo_data *data = entry->data;
+
+	spin_lock(&data_lock);
+	data->open = 0;
+	spin_unlock(&data_lock);
+	return 0;
+}
+
+static void
+call_on_cpu(int cpu, void (*fn)(void *), void *arg)
+{
+	if (cpu == smp_processor_id())
+		(*fn)(arg);
+#ifdef CONFIG_SMP
+	else if (cpu_online(cpu))	/* cpu may not have been validated */
+		smp_call_function_single(cpu, fn, arg, 0, 1);
+#endif
+}
+
+static void
+salinfo_log_read_cpu(void *context)
+{
+	struct salinfo_log_data *info = context;
+	struct salinfo_event *event = salinfo_event[info->type];
+	u64 size;
+
+	size = ia64_sal_get_state_info_size(info->type);
+	info->log_buffer = kmalloc(size, GFP_ATOMIC);
+	if (!info->log_buffer)
+		return;
+
+	clear_bit(smp_processor_id(), &event->cpu_mask);
+	info->log_size = ia64_sal_get_state_info(info->type, (u64 *) info->log_buffer);
+	if (info->log_size)
+		salinfo_log_wakeup(info->type);
+}
+
+static ssize_t
+salinfo_log_read(struct file *file, char *buffer, size_t count, loff_t *ppos)
+{
+	struct inode *inode = file->f_dentry->d_inode;
+	struct proc_dir_entry *entry = (struct proc_dir_entry *) inode->u.generic_ip;
+	struct salinfo_data *data = entry->data;
+	struct salinfo_log_data info;
+	int ret;
+	void *saldata;
+	size_t size;
+
+	info.type = data->type;
+	info.log_buffer = 0;
+	call_on_cpu(data->cpu, salinfo_log_read_cpu, &info);
+	if (!info.log_buffer || *ppos >= info.log_size) {
+		ret = 0;
+		goto out;
+	}
+
+	saldata = info.log_buffer + file->f_pos;
+	size = info.log_size - file->f_pos;
+	if (size > count)
+		size = count;
+	if (copy_to_user(buffer, saldata, size)) {
+		ret = -EFAULT;
+		goto out;
+	}
+
+	*ppos += size;
+	ret = size;
+
+out:
+	kfree(info.log_buffer);
+	return ret;
+}
+
+static void
+salinfo_log_clear_cpu(void *context)
+{
+	struct salinfo_data *data = context;
+	struct salinfo_event *event = salinfo_event[data->type];
+	struct salinfo_log_data info;
+
+	clear_bit(smp_processor_id(), &event->cpu_mask);
+	ia64_sal_clear_state_info(data->type);
+
+	/* clearing one record may make another visible */
+	info.type = data->type;
+	salinfo_log_read_cpu(&info);
+	if (info.log_buffer && info.log_size)
+		salinfo_log_wakeup(data->type);
+
+	kfree(info.log_buffer);
+}
+
+static ssize_t
+salinfo_log_write(struct file *file, const char *buffer, size_t count, loff_t *ppos)
+{
+	struct inode *inode = file->f_dentry->d_inode;
+	struct proc_dir_entry *entry = (struct proc_dir_entry *) inode->u.generic_ip;
+	struct salinfo_data *data = entry->data;
+	char cmd[32];
+	size_t size;
+	int cpu;
+
+	size = sizeof(cmd);
+	if (count < size)
+		size = count;
+	if (copy_from_user(cmd, buffer, size))
+		return -EFAULT;
+
+	if (sscanf(cmd, "read %d", &cpu) == 1)
+		data->cpu = cpu;
+	else if (sscanf(cmd, "clear %d", &cpu) == 1)
+		call_on_cpu(cpu, salinfo_log_clear_cpu, data);
+
+	return count;
+}
+
+static struct file_operations salinfo_data_fops = {
+	.open    = salinfo_log_open,
+	.release = salinfo_log_release,
+	.read    = salinfo_log_read,
+	.write   = salinfo_log_write,
+};
 
 static int __init
 salinfo_init(void)
 {
 	struct proc_dir_entry *salinfo_dir; /* /proc/sal dir entry */
 	struct proc_dir_entry **sdir = salinfo_proc_entries; /* keeps track of every entry */
-	int i;
+	struct proc_dir_entry *dir, *entry;
+	struct salinfo_event *event;
+	struct salinfo_data *data;
+	int i, j;
 
 	salinfo_dir = proc_mkdir("sal", NULL);
+	if (!salinfo_dir)
+		return 0;
 
 	for (i=0; i < NR_SALINFO_ENTRIES; i++) {
 		/* pass the feature bit in question as misc data */
 		*sdir++ = create_proc_read_entry (salinfo_entries[i].name, 0, salinfo_dir,
 						  salinfo_read, (void *)salinfo_entries[i].feature);
 	}
+
+	for (i = 0; i < ARRAY_SIZE(salinfo_log_name); i++) {
+		dir = proc_mkdir(salinfo_log_name[i], salinfo_dir);
+		if (!dir)
+			continue;
+
+		entry = create_proc_entry("event", S_IRUSR, dir);
+		if (!entry)
+			continue;
+
+		event = kmalloc(sizeof(*event), GFP_KERNEL);
+		if (!event)
+			continue;
+		memset(event, 0, sizeof(*event));
+		event->type = i;
+		init_waitqueue_head(&event->queue);
+		salinfo_event[i] = event;
+		/* we missed any events before now */
+		for (j = 0; j < NR_CPUS; j++)
+			if (cpu_online(j))
+				set_bit(j, &event->cpu_mask);
+		entry->data = event;
+		entry->proc_fops = &salinfo_event_fops;
+		*sdir++ = entry;
+
+		entry = create_proc_entry("data", S_IRUSR | S_IWUSR, dir);
+		if (!entry)
+			continue;
+
+		data = &salinfo_data[i];
+		data->type = i;
+		entry->data = data;
+		entry->proc_fops = &salinfo_data_fops;
+		*sdir++ = entry;
+
+		*sdir++ = dir;
+	}
+
 	*sdir++ = salinfo_dir;
 
 	return 0;
@@ -69,7 +373,7 @@
 {
 	int i = 0;
 
-	for (i = 0; i < NR_SALINFO_ENTRIES ; i++) {
+	for (i = 0; i < ARRAY_SIZE(salinfo_proc_entries); i++) {
 		if (salinfo_proc_entries[i])
 			remove_proc_entry (salinfo_proc_entries[i]->name, NULL);
 	}