ext4: Add fallback for find_group_flex

[safe/jmp/linux-2.6] / fs / sysfs / file.c

diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 3f07893..1f4a3f8 100644 (file)
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -19,10 +19,18 @@
 #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
@@ -328,6 +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))
@@ -337,9 +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;
        }
 
@@ -441,7 +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;
 
@@ -451,19 +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);
 }