sysfs: add sysfs_open_file->sd and ->file

sysfs will be converted to use seq_file for read path, which will make
it difficult to pass around multiple pointers directly.  This patch
adds sysfs_open_file->sd and ->file so that we can reach all the
necessary data structures from sysfs_open_file.

flush_write_buffer() is updated to drop @dentry which was used to
discover the sysfs_dirent as it's now available through
sysfs_open_file->sd.

This patch doesn't cause any behavior difference.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Tejun Heo 2013-10-01 17:42:00 -04:00 committed by Greg Kroah-Hartman
parent 58282d8dc2
commit bcafe4eea3

View file

@ -45,6 +45,8 @@ struct sysfs_open_dirent {
};
struct sysfs_open_file {
struct sysfs_dirent *sd;
struct file *file;
size_t count;
char *page;
struct mutex mutex;
@ -192,7 +194,6 @@ static int fill_write_buffer(struct sysfs_open_file *of,
/**
* flush_write_buffer - push buffer to kobject.
* @dentry: dentry to the attribute
* @of: open file
* @count: number of bytes
*
@ -200,22 +201,20 @@ static int fill_write_buffer(struct sysfs_open_file *of,
* dealing with, then call the store() method for the attribute,
* passing the buffer that we acquired in fill_write_buffer().
*/
static int flush_write_buffer(struct dentry *dentry,
struct sysfs_open_file *of, size_t count)
static int flush_write_buffer(struct sysfs_open_file *of, size_t count)
{
struct sysfs_dirent *attr_sd = dentry->d_fsdata;
struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
struct kobject *kobj = of->sd->s_parent->s_dir.kobj;
const struct sysfs_ops *ops;
int rc;
/* need attr_sd for attr and ops, its parent for kobj */
if (!sysfs_get_active(attr_sd))
/* need @of->sd for attr and ops, its parent for kobj */
if (!sysfs_get_active(of->sd))
return -ENODEV;
ops = sysfs_file_ops(attr_sd);
rc = ops->store(kobj, attr_sd->s_attr.attr, of->page, count);
ops = sysfs_file_ops(of->sd);
rc = ops->store(kobj, of->sd->s_attr.attr, of->page, count);
sysfs_put_active(attr_sd);
sysfs_put_active(of->sd);
return rc;
}
@ -245,7 +244,7 @@ static ssize_t sysfs_write_file(struct file *file, const char __user *buf,
mutex_lock(&of->mutex);
len = fill_write_buffer(of, buf, count);
if (len > 0)
len = flush_write_buffer(file->f_path.dentry, of, len);
len = flush_write_buffer(of, len);
if (len > 0)
*ppos += len;
mutex_unlock(&of->mutex);
@ -385,6 +384,8 @@ static int sysfs_open_file(struct inode *inode, struct file *file)
goto err_out;
mutex_init(&of->mutex);
of->sd = attr_sd;
of->file = file;
file->private_data = of;
/* make sure we have open dirent struct */