Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc

[pandora-kernel.git] / fs / sysfs / file.c

diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index a271c87..ade9a7e 100644 (file)
--- 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