#include <linux/dnotify.h>
#include <linux/kobject.h>
#include <asm/uaccess.h>
+#include <asm/semaphore.h>
#include "sysfs.h"
-static struct file_operations sysfs_file_operations;
-
-static int init_file(struct inode * inode)
-{
- inode->i_size = PAGE_SIZE;
- inode->i_fop = &sysfs_file_operations;
- return 0;
-}
-
#define to_subsys(k) container_of(k,struct subsystem,kset.kobj)
#define to_sattr(a) container_of(a,struct subsys_attribute,attr)
loff_t pos;
char * page;
struct sysfs_ops * ops;
+ struct semaphore sem;
+ int needs_read_fill;
};
/**
* fill_read_buffer - allocate and fill buffer from object.
- * @file: file pointer.
+ * @dentry: dentry pointer.
* @buffer: data buffer for file.
*
* Allocate @buffer->page, if it hasn't been already, then call the
* data.
* This is called only once, on the file's first read.
*/
-static int fill_read_buffer(struct file * file, struct sysfs_buffer * buffer)
+static int fill_read_buffer(struct dentry * dentry, struct sysfs_buffer * buffer)
{
- struct attribute * attr = file->f_dentry->d_fsdata;
- struct kobject * kobj = file->f_dentry->d_parent->d_fsdata;
+ struct attribute * attr = to_attr(dentry);
+ struct kobject * kobj = to_kobj(dentry->d_parent);
struct sysfs_ops * ops = buffer->ops;
int ret = 0;
ssize_t count;
return -ENOMEM;
count = ops->show(kobj,attr,buffer->page);
+ buffer->needs_read_fill = 0;
BUG_ON(count > (ssize_t)PAGE_SIZE);
if (count >= 0)
buffer->count = count;
{
int error;
+ if (*ppos > buffer->count)
+ return 0;
+
if (count > (buffer->count - *ppos))
count = buffer->count - *ppos;
struct sysfs_buffer * buffer = file->private_data;
ssize_t retval = 0;
- if (!*ppos) {
- if ((retval = fill_read_buffer(file,buffer)))
- return retval;
+ down(&buffer->sem);
+ if (buffer->needs_read_fill) {
+ if ((retval = fill_read_buffer(file->f_dentry,buffer)))
+ goto out;
}
pr_debug("%s: count = %d, ppos = %lld, buf = %s\n",
__FUNCTION__,count,*ppos,buffer->page);
- return flush_read_buffer(buffer,buf,count,ppos);
+ retval = flush_read_buffer(buffer,buf,count,ppos);
+out:
+ up(&buffer->sem);
+ return retval;
}
if (count >= PAGE_SIZE)
count = PAGE_SIZE - 1;
error = copy_from_user(buffer->page,buf,count);
+ buffer->needs_read_fill = 1;
return error ? -EFAULT : count;
}
*/
static int
-flush_write_buffer(struct file * file, struct sysfs_buffer * buffer, size_t count)
+flush_write_buffer(struct dentry * dentry, struct sysfs_buffer * buffer, size_t count)
{
- struct attribute * attr = file->f_dentry->d_fsdata;
- struct kobject * kobj = file->f_dentry->d_parent->d_fsdata;
+ struct attribute * attr = to_attr(dentry);
+ struct kobject * kobj = to_kobj(dentry->d_parent);
struct sysfs_ops * ops = buffer->ops;
return ops->store(kobj,attr,buffer->page,count);
sysfs_write_file(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
{
struct sysfs_buffer * buffer = file->private_data;
-
- count = fill_write_buffer(buffer,buf,count);
- if (count > 0)
- count = flush_write_buffer(file,buffer,count);
- if (count > 0)
- *ppos += count;
- return count;
+ ssize_t len;
+
+ down(&buffer->sem);
+ len = fill_write_buffer(buffer, buf, count);
+ if (len > 0)
+ len = flush_write_buffer(file->f_dentry, buffer, len);
+ if (len > 0)
+ *ppos += len;
+ up(&buffer->sem);
+ return len;
}
static int check_perm(struct inode * inode, struct file * file)
{
struct kobject *kobj = sysfs_get_kobject(file->f_dentry->d_parent);
- struct attribute * attr = file->f_dentry->d_fsdata;
+ struct attribute * attr = to_attr(file->f_dentry);
struct sysfs_buffer * buffer;
struct sysfs_ops * ops = NULL;
int error = 0;
buffer = kmalloc(sizeof(struct sysfs_buffer),GFP_KERNEL);
if (buffer) {
memset(buffer,0,sizeof(struct sysfs_buffer));
+ init_MUTEX(&buffer->sem);
+ buffer->needs_read_fill = 1;
buffer->ops = ops;
file->private_data = buffer;
} else
static int sysfs_release(struct inode * inode, struct file * filp)
{
- struct kobject * kobj = filp->f_dentry->d_parent->d_fsdata;
- struct attribute * attr = filp->f_dentry->d_fsdata;
+ struct kobject * kobj = to_kobj(filp->f_dentry->d_parent);
+ struct attribute * attr = to_attr(filp->f_dentry);
+ struct module * owner = attr->owner;
struct sysfs_buffer * buffer = filp->private_data;
if (kobj)
kobject_put(kobj);
- module_put(attr->owner);
+ /* After this point, attr should not be accessed. */
+ module_put(owner);
if (buffer) {
if (buffer->page)
return 0;
}
-static struct file_operations sysfs_file_operations = {
+struct file_operations sysfs_file_operations = {
.read = sysfs_read_file,
.write = sysfs_write_file,
.llseek = generic_file_llseek,
};
-int sysfs_add_file(struct dentry * dir, const struct attribute * attr)
+int sysfs_add_file(struct dentry * dir, const struct attribute * attr, int type)
{
- struct dentry * dentry;
- int error;
+ struct sysfs_dirent * parent_sd = dir->d_fsdata;
+ umode_t mode = (attr->mode & S_IALLUGO) | S_IFREG;
+ int error = 0;
down(&dir->d_inode->i_sem);
- dentry = sysfs_get_dentry(dir,attr->name);
- if (!IS_ERR(dentry)) {
- error = sysfs_create(dentry,
- (attr->mode & S_IALLUGO) | S_IFREG,
- init_file);
- if (!error)
- dentry->d_fsdata = (void *)attr;
- dput(dentry);
- } else
- error = PTR_ERR(dentry);
+ error = sysfs_make_dirent(parent_sd, NULL, (void *) attr, mode, type);
up(&dir->d_inode->i_sem);
+
return error;
}
int sysfs_create_file(struct kobject * kobj, const struct attribute * attr)
{
- if (kobj && attr)
- return sysfs_add_file(kobj->dentry,attr);
- return -EINVAL;
+ BUG_ON(!kobj || !kobj->dentry || !attr);
+
+ return sysfs_add_file(kobj->dentry, attr, SYSFS_KOBJ_ATTR);
+
}
*/
dput(victim);
res = 0;
- }
+ } else
+ d_drop(victim);
/**
* Drop the reference acquired from sysfs_get_dentry() above.
}
-EXPORT_SYMBOL(sysfs_create_file);
-EXPORT_SYMBOL(sysfs_remove_file);
-EXPORT_SYMBOL(sysfs_update_file);
+EXPORT_SYMBOL_GPL(sysfs_create_file);
+EXPORT_SYMBOL_GPL(sysfs_remove_file);
+EXPORT_SYMBOL_GPL(sysfs_update_file);
git://git.onelab.eu / linux-2.6.git / blobdiff