static int configfs_release_bin_file(struct inode *inode, struct file *filp)
{
struct configfs_buffer *buffer = filp->private_data;
struct dentry *dentry = filp->f_path.dentry;
struct config_item *item = to_item(dentry->d_parent);
struct configfs_item_operations *ops = buffer->ops;
struct configfs_bin_attribute *bin_attr = to_bin_attr(dentry);
ssize_t len = 0;
int ret;
buffer->read_in_progress = 0;
if (buffer->write_in_progress) {
buffer->write_in_progress = 0;
len = ops->write_bin_attribute(item, bin_attr,
buffer->bin_buffer, buffer->bin_buffer_size);
/* vfree on NULL is safe */
vfree(buffer->bin_buffer);
buffer->bin_buffer = NULL;
buffer->bin_buffer_size = 0;
buffer->needs_read_fill = 1;
}
ret = do_release(inode, filp,
to_item(filp->f_path.dentry->d_parent),
to_attr(filp->f_path.dentry), CONFIGFS_ITEM_BIN_ATTR);
if (len < 0)
return len;
return ret;
}
static ssize_t
configfs_read_bin_file(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
struct configfs_buffer *buffer = file->private_data;
struct dentry *dentry = file->f_path.dentry;
struct config_item *item = to_item(dentry->d_parent);
struct configfs_bin_attribute *bin_attr = to_bin_attr(dentry);
ssize_t retval = 0;
ssize_t len = min_t(size_t, count, PAGE_SIZE);
mutex_lock(&buffer->mutex);
/* we don't support switching read/write modes */
if (buffer->write_in_progress) {
retval = -ETXTBSY;
goto out;
}
buffer->read_in_progress = 1;
if (buffer->needs_read_fill) {
/* perform first read with buf == NULL to get extent */
len = bin_attr->read(item, NULL, 0);
if (len <= 0) {
retval = len;
goto out;
}
/* do not exceed the maximum value */
if (bin_attr->cb_max_size && len > bin_attr->cb_max_size) {
retval = -EFBIG;
goto out;
}
buffer->bin_buffer = vmalloc(len);
if (buffer->bin_buffer == NULL) {
retval = -ENOMEM;
goto out;
}
buffer->bin_buffer_size = len;
/* perform second read to fill buffer */
len = bin_attr->read(item, buffer->bin_buffer, len);
if (len < 0) {
retval = len;
vfree(buffer->bin_buffer);
buffer->bin_buffer_size = 0;
buffer->bin_buffer = NULL;
goto out;
}
buffer->needs_read_fill = 0;
}
retval = simple_read_from_buffer(buf, count, ppos, buffer->bin_buffer,
buffer->bin_buffer_size);
out:
mutex_unlock(&buffer->mutex);
return retval;
}
static int
flush_write_buffer(struct dentry * dentry, struct configfs_buffer * buffer, size_t count)
{
struct configfs_attribute * attr = to_attr(dentry);
struct config_item * item = to_item(dentry->d_parent);
return attr->store(item, buffer->page, count);
}
static int
flush_write_buffer(struct dentry * dentry, struct configfs_buffer * buffer, size_t count)
{
struct configfs_attribute * attr = to_attr(dentry);
struct config_item * item = to_item(dentry->d_parent);
struct configfs_item_operations * ops = buffer->ops;
return ops->store_attribute(item,attr,buffer->page,count);
}
static int configfs_release(struct inode * inode, struct file * filp)
{
struct config_item * item = to_item(filp->f_dentry->d_parent);
struct configfs_attribute * attr = to_attr(filp->f_dentry);
struct module * owner = attr->ca_owner;
struct configfs_buffer * buffer = filp->private_data;
if (item)
config_item_put(item);
/* After this point, attr should not be accessed. */
module_put(owner);
if (buffer) {
if (buffer->page)
free_page((unsigned long)buffer->page);
kfree(buffer);
}
return 0;
}
/**
* fill_read_buffer - allocate and fill buffer from item.
* @dentry: dentry pointer.
* @buffer: data buffer for file.
*
* Allocate @buffer->page, if it hasn't been already, then call the
* config_item's show() method to fill the buffer with this attribute's
* data.
* This is called only once, on the file's first read.
*/
static int fill_read_buffer(struct dentry * dentry, struct configfs_buffer * buffer)
{
struct configfs_attribute * attr = to_attr(dentry);
struct config_item * item = to_item(dentry->d_parent);
struct configfs_item_operations * ops = buffer->ops;
int ret = 0;
ssize_t count;
if (!buffer->page)
buffer->page = (char *) get_zeroed_page(GFP_KERNEL);
if (!buffer->page)
return -ENOMEM;
count = ops->show_attribute(item,attr,buffer->page);
buffer->needs_read_fill = 0;
BUG_ON(count > (ssize_t)SIMPLE_ATTR_SIZE);
if (count >= 0)
buffer->count = count;
else
ret = count;
return ret;
}
static int configfs_release_file(struct inode *inode, struct file *filp)
{
return do_release(inode, filp,
to_item(filp->f_path.dentry->d_parent),
to_attr(filp->f_path.dentry), CONFIGFS_ITEM_ATTR);
}