#include <linux/namei.h>
#include <linux/poll.h>
#include <linux/list.h>
+#include <linux/mutex.h>
#include <asm/uaccess.h>
-#include <asm/semaphore.h>
#include "sysfs.h"
.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 mutex mutex;
+ 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;
struct sysfs_buffer * buffer = file->private_data;
ssize_t retval = 0;
- down(&buffer->sem);
+ mutex_lock(&buffer->mutex);
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;
}
retval = simple_read_from_buffer(buf, count, ppos, buffer->page,
buffer->count);
out:
- up(&buffer->sem);
+ mutex_unlock(&buffer->mutex);
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;
}
struct sysfs_buffer * buffer = file->private_data;
ssize_t len;
- down(&buffer->sem);
- if (buffer->orphaned) {
- len = -ENODEV;
- goto out;
- }
+ mutex_lock(&buffer->mutex);
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);
+ mutex_unlock(&buffer->mutex);
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;
-
- Einval:
- error = -EINVAL;
- goto Done;
- Eaccess:
- error = -EACCES;
- module_put(attr->owner);
- Done:
- if (error)
- kobject_put(kobj);
+ if (!buffer)
+ goto err_out;
+
+ mutex_init(&buffer->mutex);
+ 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;
-static struct dentry *step_down(struct dentry *dir, const char * name)
-{
- struct dentry * de;
-
- if (dir == NULL || dir->d_inode == NULL)
- return NULL;
-
- mutex_lock(&dir->d_inode->i_mutex);
- de = lookup_one_len(name, dir, strlen(name));
- mutex_unlock(&dir->d_inode->i_mutex);
- dput(dir);
- if (IS_ERR(de))
- return NULL;
- if (de->d_inode == NULL) {
- dput(de);
- return NULL;
- }
- return de;
+ trigger:
+ buffer->needs_read_fill = 1;
+ return POLLERR|POLLPRI;
}
-void sysfs_notify(struct kobject * k, char *dir, char *attr)
+void sysfs_notify(struct kobject *k, char *dir, char *attr)
{
- struct dentry *de = k->dentry;
- if (de)
- dget(de);
- if (de && dir)
- de = step_down(de, dir);
- if (de && attr)
- de = step_down(de, attr);
- if (de) {
- struct sysfs_dirent * sd = de->d_fsdata;
- if (sd)
- atomic_inc(&sd->s_event);
+ struct sysfs_dirent *sd = k->sd;
+
+ mutex_lock(&sysfs_mutex);
+
+ if (sd && dir)
+ sd = sysfs_find_dirent(sd, dir);
+ if (sd && attr)
+ sd = sysfs_find_dirent(sd, attr);
+ if (sd) {
+ atomic_inc(&sd->s_event);
wake_up_interruptible(&k->poll);
- dput(de);
}
+
+ mutex_unlock(&sysfs_mutex);
}
EXPORT_SYMBOL_GPL(sysfs_notify);
};
-int sysfs_add_file(struct dentry * dir, const struct attribute * attr, int type)
+int sysfs_add_file(struct sysfs_dirent *dir_sd, const struct attribute *attr,
+ int type)
{
- struct sysfs_dirent * parent_sd = dir->d_fsdata;
umode_t mode = (attr->mode & S_IALLUGO) | S_IFREG;
- int error = -EEXIST;
+ struct sysfs_addrm_cxt acxt;
+ struct sysfs_dirent *sd;
+ int rc;
- 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);
+ sd = sysfs_new_dirent(attr->name, mode, type);
+ if (!sd)
+ return -ENOMEM;
+ sd->s_elem.attr.attr = (void *)attr;
- return error;
+ sysfs_addrm_start(&acxt, dir_sd);
+ rc = sysfs_add_one(&acxt, sd);
+ sysfs_addrm_finish(&acxt);
+
+ if (rc)
+ sysfs_put(sd);
+
+ return rc;
}
int sysfs_create_file(struct kobject * kobj, const struct attribute * attr)
{
- BUG_ON(!kobj || !kobj->dentry || !attr);
+ BUG_ON(!kobj || !kobj->sd || !attr);
- return sysfs_add_file(kobj->dentry, attr, SYSFS_KOBJ_ATTR);
+ return sysfs_add_file(kobj->sd, attr, SYSFS_KOBJ_ATTR);
}
int sysfs_add_file_to_group(struct kobject *kobj,
const struct attribute *attr, const char *group)
{
- struct dentry *dir;
+ struct sysfs_dirent *dir_sd;
int error;
- dir = lookup_one_len(group, kobj->dentry, strlen(group));
- if (IS_ERR(dir))
- error = PTR_ERR(dir);
- else {
- error = sysfs_add_file(dir, attr, SYSFS_KOBJ_ATTR);
- dput(dir);
- }
+ dir_sd = sysfs_get_dirent(kobj->sd, group);
+ if (!dir_sd)
+ return -ENOENT;
+
+ error = sysfs_add_file(dir_sd, attr, SYSFS_KOBJ_ATTR);
+ sysfs_put(dir_sd);
+
return error;
}
EXPORT_SYMBOL_GPL(sysfs_add_file_to_group);
*/
int sysfs_update_file(struct kobject * kobj, const struct attribute * attr)
{
- struct dentry * dir = kobj->dentry;
- struct dentry * victim;
- int res = -ENOENT;
-
- mutex_lock(&dir->d_inode->i_mutex);
- victim = lookup_one_len(attr->name, dir, strlen(attr->name));
- if (!IS_ERR(victim)) {
- /* make sure dentry is really there */
- if (victim->d_inode &&
- (victim->d_parent->d_inode == dir->d_inode)) {
- victim->d_inode->i_mtime = CURRENT_TIME;
- fsnotify_modify(victim);
- res = 0;
- } else
- d_drop(victim);
-
- /**
- * Drop the reference acquired from lookup_one_len() above.
- */
- dput(victim);
+ struct sysfs_dirent *victim_sd = NULL;
+ struct dentry *victim = NULL;
+ int rc;
+
+ rc = -ENOENT;
+ victim_sd = sysfs_get_dirent(kobj->sd, attr->name);
+ if (!victim_sd)
+ goto out;
+
+ victim = sysfs_get_dentry(victim_sd);
+ if (IS_ERR(victim)) {
+ rc = PTR_ERR(victim);
+ victim = NULL;
+ goto out;
}
- mutex_unlock(&dir->d_inode->i_mutex);
- return res;
+ mutex_lock(&victim->d_inode->i_mutex);
+ victim->d_inode->i_mtime = CURRENT_TIME;
+ fsnotify_modify(victim);
+ mutex_unlock(&victim->d_inode->i_mutex);
+ rc = 0;
+ out:
+ dput(victim);
+ sysfs_put(victim_sd);
+ return rc;
}
*/
int sysfs_chmod_file(struct kobject *kobj, struct attribute *attr, mode_t mode)
{
- struct dentry *dir = kobj->dentry;
- struct dentry *victim;
+ struct sysfs_dirent *victim_sd = NULL;
+ struct dentry *victim = NULL;
struct inode * inode;
struct iattr newattrs;
- int res = -ENOENT;
-
- mutex_lock(&dir->d_inode->i_mutex);
- victim = lookup_one_len(attr->name, dir, strlen(attr->name));
- if (!IS_ERR(victim)) {
- if (victim->d_inode &&
- (victim->d_parent->d_inode == dir->d_inode)) {
- inode = victim->d_inode;
- mutex_lock(&inode->i_mutex);
- newattrs.ia_mode = (mode & S_IALLUGO) |
- (inode->i_mode & ~S_IALLUGO);
- newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
- res = notify_change(victim, &newattrs);
- mutex_unlock(&inode->i_mutex);
- }
- dput(victim);
+ int rc;
+
+ rc = -ENOENT;
+ victim_sd = sysfs_get_dirent(kobj->sd, attr->name);
+ if (!victim_sd)
+ goto out;
+
+ victim = sysfs_get_dentry(victim_sd);
+ if (IS_ERR(victim)) {
+ rc = PTR_ERR(victim);
+ victim = NULL;
+ goto out;
}
- mutex_unlock(&dir->d_inode->i_mutex);
- return res;
+ inode = victim->d_inode;
+ mutex_lock(&inode->i_mutex);
+ newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
+ newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
+ rc = notify_change(victim, &newattrs);
+ mutex_unlock(&inode->i_mutex);
+ out:
+ dput(victim);
+ sysfs_put(victim_sd);
+ return rc;
}
EXPORT_SYMBOL_GPL(sysfs_chmod_file);
void sysfs_remove_file(struct kobject * kobj, const struct attribute * attr)
{
- sysfs_hash_and_remove(kobj->dentry, attr->name);
+ sysfs_hash_and_remove(kobj->sd, attr->name);
}
void sysfs_remove_file_from_group(struct kobject *kobj,
const struct attribute *attr, const char *group)
{
- struct dentry *dir;
+ struct sysfs_dirent *dir_sd;
- dir = lookup_one_len(group, kobj->dentry, strlen(group));
- if (!IS_ERR(dir)) {
- sysfs_hash_and_remove(dir, attr->name);
- dput(dir);
+ dir_sd = sysfs_get_dirent(kobj->sd, group);
+ if (dir_sd) {
+ sysfs_hash_and_remove(dir_sd, attr->name);
+ sysfs_put(dir_sd);
}
}
EXPORT_SYMBOL_GPL(sysfs_remove_file_from_group);
projects / cascardo / linux.git / blobdiff