1 files changed, 37 insertions, 17 deletions

diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index e7735f643cd1..1f4a3f877262 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -14,14 +14,23 @@
 #include <linux/kobject.h>
 #include <linux/kallsyms.h>
 #include <linux/slab.h>
+#include <linux/fsnotify.h>
 #include <linux/namei.h>
 #include <linux/poll.h>
 #include <linux/list.h>
 #include <linux/mutex.h>
+#include <linux/limits.h>
 #include <asm/uaccess.h>
 
 #include "sysfs.h"
 
+/* used in crash dumps to help with debugging */
+static char last_sysfs_file[PATH_MAX];
+void sysfs_printk_last_file(void)
+{
+	printk(KERN_EMERG "last sysfs file: %s\n", last_sysfs_file);
+}
+
 /*
  * There's one sysfs_buffer for each open file and one
  * sysfs_open_dirent for each sysfs_dirent with one or more open
@@ -327,6 +336,11 @@ static int sysfs_open_file(struct inode *inode, struct file *file)
 	struct sysfs_buffer *buffer;
 	struct sysfs_ops *ops;
 	int error = -EACCES;
+	char *p;
+
+	p = d_path(&file->f_path, last_sysfs_file, sizeof(last_sysfs_file));
+	if (p)
+		memmove(last_sysfs_file, p, strlen(p) + 1);
 
 	/* need attr_sd for attr and ops, its parent for kobj */
 	if (!sysfs_get_active_two(attr_sd))
@@ -336,9 +350,8 @@ static int sysfs_open_file(struct inode *inode, struct file *file)
 	if (kobj->ktype && kobj->ktype->sysfs_ops)
 		ops = kobj->ktype->sysfs_ops;
 	else {
-		printk(KERN_ERR "missing sysfs attribute operations for "
+		WARN(1, KERN_ERR "missing sysfs attribute operations for "
 		       "kobject: %s\n", kobject_name(kobj));
-		WARN_ON(1);
 		goto err_out;
 	}
 
@@ -440,7 +453,23 @@ static unsigned int sysfs_poll(struct file *filp, poll_table *wait)
 	return POLLERR|POLLPRI;
 }
 
-void sysfs_notify(struct kobject *k, char *dir, char *attr)
+void sysfs_notify_dirent(struct sysfs_dirent *sd)
+{
+	struct sysfs_open_dirent *od;
+
+	spin_lock(&sysfs_open_dirent_lock);
+
+	od = sd->s_attr.open;
+	if (od) {
+		atomic_inc(&od->event);
+		wake_up_interruptible(&od->poll);
+	}
+
+	spin_unlock(&sysfs_open_dirent_lock);
+}
+EXPORT_SYMBOL_GPL(sysfs_notify_dirent);
+
+void sysfs_notify(struct kobject *k, const char *dir, const char *attr)
 {
 	struct sysfs_dirent *sd = k->sd;
 
@@ -450,19 +479,8 @@ void sysfs_notify(struct kobject *k, char *dir, char *attr)
 		sd = sysfs_find_dirent(sd, dir);
 	if (sd && attr)
 		sd = sysfs_find_dirent(sd, attr);
-	if (sd) {
-		struct sysfs_open_dirent *od;
-
-		spin_lock(&sysfs_open_dirent_lock);
-
-		od = sd->s_attr.open;
-		if (od) {
-			atomic_inc(&od->event);
-			wake_up_interruptible(&od->poll);
-		}
-
-		spin_unlock(&sysfs_open_dirent_lock);
-	}
+	if (sd)
+		sysfs_notify_dirent(sd);
 
 	mutex_unlock(&sysfs_mutex);
 }
@@ -585,9 +603,11 @@ int sysfs_chmod_file(struct kobject *kobj, struct attribute *attr, mode_t mode)
 
 	newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
 	newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
-	rc = notify_change(victim, &newattrs);
+	newattrs.ia_ctime = current_fs_time(inode->i_sb);
+	rc = sysfs_setattr(victim, &newattrs);
 
 	if (rc == 0) {
+		fsnotify_change(victim, newattrs.ia_valid);
 		mutex_lock(&sysfs_mutex);
 		victim_sd->s_mode = newattrs.ia_mode;
 		mutex_unlock(&sysfs_mutex);