mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-22 17:01:14 +00:00
![Linus Torvalds](/assets/img/avatar_default.png)
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
204 lines
4.3 KiB
C
204 lines
4.3 KiB
C
/*
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* bin.c - binary file operations for sysfs.
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*
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* Copyright (c) 2003 Patrick Mochel
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* Copyright (c) 2003 Matthew Wilcox
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* Copyright (c) 2004 Silicon Graphics, Inc.
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*/
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#undef DEBUG
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#include <linux/errno.h>
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#include <linux/fs.h>
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#include <linux/kobject.h>
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <asm/uaccess.h>
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#include "sysfs.h"
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static int
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fill_read(struct dentry *dentry, char *buffer, loff_t off, size_t count)
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{
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struct bin_attribute * attr = to_bin_attr(dentry);
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struct kobject * kobj = to_kobj(dentry->d_parent);
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if (!attr->read)
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return -EINVAL;
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return attr->read(kobj, buffer, off, count);
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}
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static ssize_t
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read(struct file * file, char __user * userbuf, size_t count, loff_t * off)
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{
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char *buffer = file->private_data;
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struct dentry *dentry = file->f_dentry;
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int size = dentry->d_inode->i_size;
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loff_t offs = *off;
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int ret;
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if (count > PAGE_SIZE)
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count = PAGE_SIZE;
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if (size) {
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if (offs > size)
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return 0;
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if (offs + count > size)
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count = size - offs;
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}
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ret = fill_read(dentry, buffer, offs, count);
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if (ret < 0)
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return ret;
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count = ret;
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if (copy_to_user(userbuf, buffer, count))
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return -EFAULT;
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pr_debug("offs = %lld, *off = %lld, count = %zd\n", offs, *off, count);
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*off = offs + count;
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return count;
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}
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static int
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flush_write(struct dentry *dentry, char *buffer, loff_t offset, size_t count)
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{
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struct bin_attribute *attr = to_bin_attr(dentry);
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struct kobject *kobj = to_kobj(dentry->d_parent);
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if (!attr->write)
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return -EINVAL;
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return attr->write(kobj, buffer, offset, count);
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}
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static ssize_t write(struct file * file, const char __user * userbuf,
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size_t count, loff_t * off)
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{
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char *buffer = file->private_data;
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struct dentry *dentry = file->f_dentry;
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int size = dentry->d_inode->i_size;
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loff_t offs = *off;
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if (count > PAGE_SIZE)
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count = PAGE_SIZE;
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if (size) {
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if (offs > size)
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return 0;
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if (offs + count > size)
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count = size - offs;
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}
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if (copy_from_user(buffer, userbuf, count))
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return -EFAULT;
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count = flush_write(dentry, buffer, offs, count);
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if (count > 0)
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*off = offs + count;
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return count;
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}
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static int mmap(struct file *file, struct vm_area_struct *vma)
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{
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struct dentry *dentry = file->f_dentry;
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struct bin_attribute *attr = to_bin_attr(dentry);
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struct kobject *kobj = to_kobj(dentry->d_parent);
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if (!attr->mmap)
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return -EINVAL;
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return attr->mmap(kobj, attr, vma);
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}
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static int open(struct inode * inode, struct file * file)
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{
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struct kobject *kobj = sysfs_get_kobject(file->f_dentry->d_parent);
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struct bin_attribute * attr = to_bin_attr(file->f_dentry);
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int error = -EINVAL;
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if (!kobj || !attr)
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goto Done;
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/* Grab the module reference for this attribute if we have one */
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error = -ENODEV;
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if (!try_module_get(attr->attr.owner))
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goto Done;
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error = -EACCES;
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if ((file->f_mode & FMODE_WRITE) && !(attr->write || attr->mmap))
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goto Error;
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if ((file->f_mode & FMODE_READ) && !(attr->read || attr->mmap))
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goto Error;
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error = -ENOMEM;
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file->private_data = kmalloc(PAGE_SIZE, GFP_KERNEL);
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if (!file->private_data)
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goto Error;
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error = 0;
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goto Done;
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Error:
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module_put(attr->attr.owner);
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Done:
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if (error && kobj)
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kobject_put(kobj);
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return error;
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}
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static int release(struct inode * inode, struct file * file)
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{
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struct kobject * kobj = to_kobj(file->f_dentry->d_parent);
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struct bin_attribute * attr = to_bin_attr(file->f_dentry);
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u8 * buffer = file->private_data;
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if (kobj)
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kobject_put(kobj);
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module_put(attr->attr.owner);
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kfree(buffer);
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return 0;
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}
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struct file_operations bin_fops = {
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.read = read,
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.write = write,
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.mmap = mmap,
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.llseek = generic_file_llseek,
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.open = open,
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.release = release,
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};
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/**
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* sysfs_create_bin_file - create binary file for object.
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* @kobj: object.
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* @attr: attribute descriptor.
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*
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*/
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int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr)
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{
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BUG_ON(!kobj || !kobj->dentry || !attr);
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return sysfs_add_file(kobj->dentry, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
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}
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/**
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* sysfs_remove_bin_file - remove binary file for object.
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* @kobj: object.
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* @attr: attribute descriptor.
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*
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*/
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int sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr)
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{
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sysfs_hash_and_remove(kobj->dentry,attr->attr.name);
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return 0;
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}
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EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
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EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);
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