#include "sysfs.h"
-#define to_subsys(k) container_of(k,struct subsystem,kset.kobj)
-#define to_sattr(a) container_of(a,struct subsys_attribute,attr)
+#define to_sattr(a) container_of(a,struct subsys_attribute, attr)
/*
* Subsystem file operations.
static ssize_t
subsys_attr_show(struct kobject * kobj, struct attribute * attr, char * page)
{
- struct subsystem * s = to_subsys(kobj);
+ struct kset *kset = to_kset(kobj);
struct subsys_attribute * sattr = to_sattr(attr);
ssize_t ret = -EIO;
if (sattr->show)
- ret = sattr->show(s,page);
+ ret = sattr->show(kset, page);
return ret;
}
subsys_attr_store(struct kobject * kobj, struct attribute * attr,
const char * page, size_t count)
{
- struct subsystem * s = to_subsys(kobj);
+ struct kset *kset = to_kset(kobj);
struct subsys_attribute * sattr = to_sattr(attr);
ssize_t ret = -EIO;
if (sattr->store)
- ret = sattr->store(s,page,count);
+ ret = sattr->store(kset, page, count);
return ret;
}
.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.
*/
static int fill_read_buffer(struct dentry * dentry, struct sysfs_buffer * buffer)
{
- struct sysfs_dirent * sd = dentry->d_fsdata;
- struct attribute * attr = to_attr(dentry);
- 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,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;
return ret;
}
-
-/**
- * flush_read_buffer - push buffer to userspace.
- * @buffer: data buffer for file.
- * @buf: user-passed buffer.
- * @count: number of bytes requested.
- * @ppos: file position.
- *
- * Copy the buffer we filled in fill_read_buffer() to userspace.
- * This is done at the reader's leisure, copying and advancing
- * the amount they specify each time.
- * This may be called continuously until the buffer is empty.
- */
-static int flush_read_buffer(struct sysfs_buffer * buffer, char __user * buf,
- size_t count, loff_t * ppos)
-{
- int error;
-
- if (*ppos > buffer->count)
- return 0;
-
- if (count > (buffer->count - *ppos))
- count = buffer->count - *ppos;
-
- error = copy_to_user(buf,buffer->page + *ppos,count);
- if (!error)
- *ppos += count;
- return error ? -EFAULT : count;
-}
-
/**
* sysfs_read_file - read an attribute.
* @file: file pointer.
ssize_t retval = 0;
down(&buffer->sem);
- if (buffer->orphaned) {
- retval = -ENODEV;
- goto out;
- }
if (buffer->needs_read_fill) {
- if ((retval = fill_read_buffer(file->f_path.dentry,buffer)))
+ retval = fill_read_buffer(file->f_path.dentry,buffer);
+ if (retval)
goto out;
}
pr_debug("%s: count = %zd, ppos = %lld, buf = %s\n",
__FUNCTION__, count, *ppos, buffer->page);
- retval = flush_read_buffer(buffer,buf,count,ppos);
+ retval = simple_read_from_buffer(buf, count, ppos, buffer->page,
+ buffer->count);
out:
up(&buffer->sem);
return retval;
* 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 attribute * attr = to_attr(dentry);
- 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 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);
- return ops->store(kobj,attr,buffer->page,count);
+ sysfs_put_active_two(attr_sd);
+
+ return rc;
}
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;
}
static int sysfs_open_file(struct inode *inode, struct file *file)
{
- struct kobject *kobj = sysfs_get_kobject(file->f_path.dentry->d_parent);
- struct attribute * attr = to_attr(file->f_path.dentry);
- struct sysfs_buffer_collection *set;
+ struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+ struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;
struct sysfs_buffer * buffer;
struct sysfs_ops * ops = NULL;
- int error = 0;
-
- if (!kobj || !attr)
- goto Einval;
+ int error;
- /* Grab the module reference for this attribute if we have one */
- if (!try_module_get(attr->owner)) {
- error = -ENODEV;
- goto Done;
- }
+ /* need attr_sd for attr and ops, its parent for kobj */
+ if (!sysfs_get_active_two(attr_sd))
+ return -ENODEV;
/* if the kobject has no ktype, then we assume that it is a subsystem
* itself, and use ops for it.
else
ops = &subsys_sysfs_ops;
+ error = -EACCES;
+
/* No sysfs operations, either from having no subsystem,
* or the subsystem have no operations.
*/
if (!ops)
- goto Eaccess;
-
- /* 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 {
- INIT_LIST_HEAD(&set->associates);
- }
- }
- mutex_unlock(&inode->i_mutex);
+ goto err_out;
/* 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_out;
}
/* File needs read support.
*/
if (file->f_mode & FMODE_READ) {
if (!(inode->i_mode & S_IRUGO) || !ops->show)
- goto Eaccess;
+ goto err_out;
}
/* 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_out;
- Einval:
- error = -EINVAL;
- goto Done;
- Eaccess:
- error = -EACCES;
- module_put(attr->owner);
- Done:
- if (error)
- kobject_put(kobj);
+ init_MUTEX(&buffer->sem);
+ buffer->needs_read_fill = 1;
+ buffer->ops = ops;
+ 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_out:
+ 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 attribute * attr = to_attr(filp->f_path.dentry);
- struct module * owner = attr->owner;
- struct sysfs_buffer * buffer = filp->private_data;
+ struct sysfs_dirent *attr_sd = filp->f_path.dentry->d_fsdata;
+ struct sysfs_buffer *buffer = filp->private_data;
- if (buffer)
- remove_from_collection(buffer, inode);
- kobject_put(kobj);
- /* After this point, attr should not be accessed. */
- module_put(owner);
+ sysfs_put(attr_sd);
if (buffer) {
if (buffer->page)
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;
}
{
struct sysfs_dirent * parent_sd = dir->d_fsdata;
umode_t mode = (attr->mode & S_IALLUGO) | S_IFREG;
- int error = -EEXIST;
+ struct sysfs_dirent *sd;
+ int error = 0;
mutex_lock(&dir->d_inode->i_mutex);
- if (!sysfs_dirent_exist(parent_sd, attr->name))
- error = sysfs_make_dirent(parent_sd, NULL, (void *)attr,
- mode, type);
- mutex_unlock(&dir->d_inode->i_mutex);
+ if (sysfs_find_dirent(parent_sd, attr->name)) {
+ error = -EEXIST;
+ goto out_unlock;
+ }
+
+ sd = sysfs_new_dirent(attr->name, mode, type);
+ if (!sd) {
+ error = -ENOMEM;
+ goto out_unlock;
+ }
+ sd->s_elem.attr.attr = (void *)attr;
+ sysfs_attach_dirent(sd, parent_sd, NULL);
+
+ out_unlock:
+ mutex_unlock(&dir->d_inode->i_mutex);
return error;
}
struct kobject *kobj;
void (*func)(void *);
void *data;
+ struct module *owner;
struct work_struct work;
};
(ss->func)(ss->data);
kobject_put(ss->kobj);
+ module_put(ss->owner);
kfree(ss);
}
* @kobj: object we're acting for.
* @func: callback function to invoke later.
* @data: argument to pass to @func.
+ * @owner: module owning the callback code
*
* sysfs attribute methods must not unregister themselves or their parent
* kobject (which would amount to the same thing). Attempts to do so will
* until @func returns.
*
* Returns 0 if the request was submitted, -ENOMEM if storage could not
- * be allocated.
+ * be allocated, -ENODEV if a reference to @owner isn't available.
*/
int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
- void *data)
+ void *data, struct module *owner)
{
struct sysfs_schedule_callback_struct *ss;
+ if (!try_module_get(owner))
+ return -ENODEV;
ss = kmalloc(sizeof(*ss), GFP_KERNEL);
- if (!ss)
+ if (!ss) {
+ module_put(owner);
return -ENOMEM;
+ }
kobject_get(kobj);
ss->kobj = kobj;
ss->func = func;
ss->data = data;
+ ss->owner = owner;
INIT_WORK(&ss->work, sysfs_schedule_callback_work);
schedule_work(&ss->work);
return 0;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff