*/
static int fill_read_buffer(struct dentry * dentry, struct sysfs_buffer * buffer)
{
- struct sysfs_dirent * sd = dentry->d_fsdata;
- struct kobject * kobj = to_kobj(dentry->d_parent);
+ struct sysfs_dirent *attr_sd = dentry->d_fsdata;
+ struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
struct sysfs_ops * ops = buffer->ops;
int ret = 0;
ssize_t count;
if (!buffer->page)
return -ENOMEM;
- buffer->event = atomic_read(&sd->s_event);
- count = ops->show(kobj, sd->s_elem.attr.attr, buffer->page);
+ /* need attr_sd for attr and ops, its parent for kobj */
+ if (!sysfs_get_active_two(attr_sd))
+ return -ENODEV;
+
+ buffer->event = atomic_read(&attr_sd->s_event);
+ count = ops->show(kobj, attr_sd->s_elem.attr.attr, buffer->page);
+
+ sysfs_put_active_two(attr_sd);
+
BUG_ON(count > (ssize_t)PAGE_SIZE);
if (count >= 0) {
buffer->needs_read_fill = 0;
* passing the buffer that we acquired in fill_write_buffer().
*/
-static int
+static int
flush_write_buffer(struct dentry * dentry, struct sysfs_buffer * buffer, size_t count)
{
struct sysfs_dirent *attr_sd = dentry->d_fsdata;
- struct kobject * kobj = to_kobj(dentry->d_parent);
+ struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
struct sysfs_ops * ops = buffer->ops;
+ int rc;
+
+ /* need attr_sd for attr and ops, its parent for kobj */
+ if (!sysfs_get_active_two(attr_sd))
+ return -ENODEV;
+
+ rc = ops->store(kobj, attr_sd->s_elem.attr.attr, buffer->page, count);
+
+ sysfs_put_active_two(attr_sd);
- return ops->store(kobj, attr_sd->s_elem.attr.attr, buffer->page, count);
+ return rc;
}
static int sysfs_open_file(struct inode *inode, struct file *file)
{
- struct kobject *kobj = sysfs_get_kobject(file->f_path.dentry->d_parent);
struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
struct attribute *attr = attr_sd->s_elem.attr.attr;
+ struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
struct sysfs_buffer_collection *set;
struct sysfs_buffer * buffer;
struct sysfs_ops * ops = NULL;
- int error = 0;
+ int error;
- if (!kobj || !attr)
- goto Einval;
+ /* need attr_sd for attr and ops, its parent for kobj */
+ if (!sysfs_get_active_two(attr_sd))
+ return -ENODEV;
- /* Grab the module reference for this attribute if we have one */
- if (!try_module_get(attr->owner)) {
- error = -ENODEV;
- goto Done;
- }
+ /* Grab the module reference for this attribute */
+ error = -ENODEV;
+ if (!try_module_get(attr->owner))
+ goto err_sput;
/* if the kobject has no ktype, then we assume that it is a subsystem
* itself, and use ops for it.
/* No sysfs operations, either from having no subsystem,
* or the subsystem have no operations.
*/
+ error = -EACCES;
if (!ops)
- goto Eaccess;
+ goto err_mput;
/* make sure we have a collection to add our buffers to */
mutex_lock(&inode->i_mutex);
if (!(set = inode->i_private)) {
- if (!(set = inode->i_private = kmalloc(sizeof(struct sysfs_buffer_collection), GFP_KERNEL))) {
- error = -ENOMEM;
- goto Done;
- } else {
+ error = -ENOMEM;
+ if (!(set = inode->i_private = kmalloc(sizeof(struct sysfs_buffer_collection), GFP_KERNEL)))
+ goto err_mput;
+ else
INIT_LIST_HEAD(&set->associates);
- }
}
mutex_unlock(&inode->i_mutex);
+ error = -EACCES;
+
/* File needs write support.
* The inode's perms must say it's ok,
* and we must have a store method.
*/
if (file->f_mode & FMODE_WRITE) {
-
if (!(inode->i_mode & S_IWUGO) || !ops->store)
- goto Eaccess;
-
+ goto err_mput;
}
/* File needs read support.
*/
if (file->f_mode & FMODE_READ) {
if (!(inode->i_mode & S_IRUGO) || !ops->show)
- goto Eaccess;
+ goto err_mput;
}
/* No error? Great, allocate a buffer for the file, and store it
* it in file->private_data for easy access.
*/
+ error = -ENOMEM;
buffer = kzalloc(sizeof(struct sysfs_buffer), GFP_KERNEL);
- if (buffer) {
- INIT_LIST_HEAD(&buffer->associates);
- init_MUTEX(&buffer->sem);
- buffer->needs_read_fill = 1;
- buffer->ops = ops;
- add_to_collection(buffer, inode);
- file->private_data = buffer;
- } else
- error = -ENOMEM;
- goto Done;
+ if (!buffer)
+ goto err_mput;
- Einval:
- error = -EINVAL;
- goto Done;
- Eaccess:
- error = -EACCES;
+ INIT_LIST_HEAD(&buffer->associates);
+ init_MUTEX(&buffer->sem);
+ buffer->needs_read_fill = 1;
+ buffer->ops = ops;
+ add_to_collection(buffer, inode);
+ file->private_data = buffer;
+
+ /* open succeeded, put active references and pin attr_sd */
+ sysfs_put_active_two(attr_sd);
+ sysfs_get(attr_sd);
+ return 0;
+
+ err_mput:
module_put(attr->owner);
- Done:
- if (error)
- kobject_put(kobj);
+ err_sput:
+ sysfs_put_active_two(attr_sd);
return error;
}
static int sysfs_release(struct inode * inode, struct file * filp)
{
- struct kobject * kobj = to_kobj(filp->f_path.dentry->d_parent);
struct sysfs_dirent *attr_sd = filp->f_path.dentry->d_fsdata;
struct attribute *attr = attr_sd->s_elem.attr.attr;
struct sysfs_buffer * buffer = filp->private_data;
if (buffer)
remove_from_collection(buffer, inode);
- kobject_put(kobj);
+ sysfs_put(attr_sd);
/* After this point, attr should not be accessed. */
module_put(attr->owner);
static unsigned int sysfs_poll(struct file *filp, poll_table *wait)
{
struct sysfs_buffer * buffer = filp->private_data;
- struct kobject * kobj = to_kobj(filp->f_path.dentry->d_parent);
- struct sysfs_dirent * sd = filp->f_path.dentry->d_fsdata;
- int res = 0;
+ struct sysfs_dirent *attr_sd = filp->f_path.dentry->d_fsdata;
+ struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
+
+ /* need parent for the kobj, grab both */
+ if (!sysfs_get_active_two(attr_sd))
+ goto trigger;
poll_wait(filp, &kobj->poll, wait);
- if (buffer->event != atomic_read(&sd->s_event)) {
- res = POLLERR|POLLPRI;
- buffer->needs_read_fill = 1;
- }
+ sysfs_put_active_two(attr_sd);
- return res;
+ if (buffer->event != atomic_read(&attr_sd->s_event))
+ goto trigger;
+
+ return 0;
+
+ trigger:
+ buffer->needs_read_fill = 1;
+ return POLLERR|POLLPRI;
}
projects / powerpc.git / blobdiff