X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=fs%2Fsysfs%2Ffile.c;h=ade9a7e6a75763cd11304a638113f86e18f09d01;hb=224a88be40c45c0da5bdc45a8118004a37c60e8a;hp=8acf82bba44c60c14f46317448c792abd19ceb52;hpb=e07dd2ad305f6b29b47d713600aa8b722ef2a9f7;p=linux-2.6-omap-h63xx.git

diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 8acf82bba44..ade9a7e6a75 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -12,6 +12,8 @@
 
 #include <linux/module.h>
 #include <linux/kobject.h>
+#include <linux/kallsyms.h>
+#include <linux/slab.h>
 #include <linux/namei.h>
 #include <linux/poll.h>
 #include <linux/list.h>
@@ -86,7 +88,12 @@ static int fill_read_buffer(struct dentry * dentry, struct sysfs_buffer * buffer
 	 * The code works fine with PAGE_SIZE return but it's likely to
 	 * indicate truncated result or overflow in normal use cases.
 	 */
-	BUG_ON(count >= (ssize_t)PAGE_SIZE);
+	if (count >= (ssize_t)PAGE_SIZE) {
+		print_symbol("fill_read_buffer: %s returned bad count\n",
+			(unsigned long)ops->show);
+		/* Try to struggle along */
+		count = PAGE_SIZE - 1;
+	}
 	if (count >= 0) {
 		buffer->needs_read_fill = 0;
 		buffer->count = count;
@@ -122,7 +129,7 @@ sysfs_read_file(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 	ssize_t retval = 0;
 
 	mutex_lock(&buffer->mutex);
-	if (buffer->needs_read_fill) {
+	if (buffer->needs_read_fill || *ppos == 0) {
 		retval = fill_read_buffer(file->f_path.dentry,buffer);
 		if (retval)
 			goto out;
@@ -403,8 +410,7 @@ static int sysfs_release(struct inode *inode, struct file *filp)
  * return POLLERR|POLLPRI, and select will return the fd whether
  * it is waiting for read, write, or exceptions.
  * Once poll/select indicates that the value has changed, you
- * need to close and re-open the file, as simply seeking and reading
- * again will not get new data, or reset the state of 'poll'.
+ * need to close and re-open the file, or seek to 0 and read again.
  * Reminder: this only works for attributes which actively support
  * it, and it is not possible to test an attribute from userspace
  * to see if it supports poll (Neither 'poll' nor 'select' return
@@ -523,7 +529,11 @@ int sysfs_add_file_to_group(struct kobject *kobj,
 	struct sysfs_dirent *dir_sd;
 	int error;
 
-	dir_sd = sysfs_get_dirent(kobj->sd, group);
+	if (group)
+		dir_sd = sysfs_get_dirent(kobj->sd, group);
+	else
+		dir_sd = sysfs_get(kobj->sd);
+
 	if (!dir_sd)
 		return -ENOENT;
 
@@ -611,7 +621,10 @@ void sysfs_remove_file_from_group(struct kobject *kobj,
 {
 	struct sysfs_dirent *dir_sd;
 
-	dir_sd = sysfs_get_dirent(kobj->sd, group);
+	if (group)
+		dir_sd = sysfs_get_dirent(kobj->sd, group);
+	else
+		dir_sd = sysfs_get(kobj->sd);
 	if (dir_sd) {
 		sysfs_hash_and_remove(dir_sd, attr->name);
 		sysfs_put(dir_sd);