.store = subsys_attr_store,
};
-/**
- * add_to_collection - add buffer to a collection
- * @buffer: buffer to be added
- * @node: inode of set to add to
- */
-
-static inline void
-add_to_collection(struct sysfs_buffer *buffer, struct inode *node)
-{
- struct sysfs_buffer_collection *set = node->i_private;
-
- mutex_lock(&node->i_mutex);
- list_add(&buffer->associates, &set->associates);
- mutex_unlock(&node->i_mutex);
-}
-
-static inline void
-remove_from_collection(struct sysfs_buffer *buffer, struct inode *node)
-{
- mutex_lock(&node->i_mutex);
- list_del(&buffer->associates);
- mutex_unlock(&node->i_mutex);
-}
+struct sysfs_buffer {
+ size_t count;
+ loff_t pos;
+ char * page;
+ struct sysfs_ops * ops;
+ struct semaphore sem;
+ int needs_read_fill;
+ int event;
+};
/**
* fill_read_buffer - allocate and fill buffer from object.
down(&buffer->sem);
if (buffer->needs_read_fill) {
- if (buffer->orphaned)
- retval = -ENODEV;
- else
- retval = fill_read_buffer(file->f_path.dentry,buffer);
+ retval = fill_read_buffer(file->f_path.dentry,buffer);
if (retval)
goto out;
}
ssize_t len;
down(&buffer->sem);
- if (buffer->orphaned) {
- len = -ENODEV;
- goto out;
- }
len = fill_write_buffer(buffer, buf, count);
if (len > 0)
len = flush_write_buffer(file->f_path.dentry, buffer, len);
if (len > 0)
*ppos += len;
-out:
up(&buffer->sem);
return len;
}
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;
else
ops = &subsys_sysfs_ops;
+ error = -EACCES;
+
/* No sysfs operations, either from having no subsystem,
* or the subsystem have no operations.
*/
- error = -EACCES;
if (!ops)
goto err_mput;
- /* make sure we have a collection to add our buffers to */
- mutex_lock(&inode->i_mutex);
- if (!(set = inode->i_private)) {
- 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 (!buffer)
goto err_mput;
- 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 */
{
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;
+ struct sysfs_buffer *buffer = filp->private_data;
- if (buffer)
- remove_from_collection(buffer, inode);
sysfs_put(attr_sd);
/* After this point, attr should not be accessed. */
module_put(attr->owner);
return error;
}
-static inline void orphan_all_buffers(struct inode *node)
-{
- struct sysfs_buffer_collection *set;
- struct sysfs_buffer *buf;
-
- mutex_lock_nested(&node->i_mutex, I_MUTEX_CHILD);
- set = node->i_private;
- if (set) {
- list_for_each_entry(buf, &set->associates, associates) {
- down(&buf->sem);
- buf->orphaned = 1;
- up(&buf->sem);
- }
- }
- mutex_unlock(&node->i_mutex);
-}
-
-
/*
* Unhashes the dentry corresponding to given sysfs_dirent
* Called with parent inode's i_mutex held.
void sysfs_drop_dentry(struct sysfs_dirent * sd, struct dentry * parent)
{
struct dentry *dentry = NULL;
- struct inode *inode;
/* We're not holding a reference to ->s_dentry dentry but the
* field will stay valid as long as sysfs_lock is held.
spin_lock(&dcache_lock);
spin_lock(&dentry->d_lock);
if (!d_unhashed(dentry) && dentry->d_inode) {
- inode = dentry->d_inode;
- spin_lock(&inode->i_lock);
- __iget(inode);
- spin_unlock(&inode->i_lock);
dget_locked(dentry);
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_lock);
simple_unlink(parent->d_inode, dentry);
- orphan_all_buffers(inode);
- iput(inode);
} else {
spin_unlock(&dentry->d_lock);
spin_unlock(&dcache_lock);
struct super_block * sysfs_sb = NULL;
struct kmem_cache *sysfs_dir_cachep;
-static void sysfs_clear_inode(struct inode *inode);
-
static const struct super_operations sysfs_ops = {
.statfs = simple_statfs,
.drop_inode = sysfs_delete_inode,
- .clear_inode = sysfs_clear_inode,
};
static struct sysfs_dirent sysfs_root = {
.s_ino = 1,
};
-static void sysfs_clear_inode(struct inode *inode)
-{
- kfree(inode->i_private);
-}
-
static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
{
struct inode *inode;