![David Howells](/assets/img/avatar_default.png)
Since __proc_create() appends the name it is given to the end of the PDE structure that it allocates, there isn't a need to store a name pointer. Instead we can just replace the name pointer with a terminal char array of _unspecified_ length. The compiler will simply append the string to statically defined variables of PDE type overlapping any hole at the end of the structure and, unlike specifying an explicitly _zero_ length array, won't give a warning if you try to statically initialise it with a string of more than zero length. Also, whilst we're at it: (1) Move namelen to end just prior to name and reduce it to a single byte (name shouldn't be longer than NAME_MAX). (2) Move pde_unload_lock two places further on so that if it's four bytes in size on a 64-bit machine, it won't cause an unused hole in the PDE struct. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
853 lines
19 KiB
C
853 lines
19 KiB
C
/*
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* proc/fs/generic.c --- generic routines for the proc-fs
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*
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* This file contains generic proc-fs routines for handling
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* directories and files.
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*
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* Copyright (C) 1991, 1992 Linus Torvalds.
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* Copyright (C) 1997 Theodore Ts'o
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*/
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#include <linux/errno.h>
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#include <linux/time.h>
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#include <linux/proc_fs.h>
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#include <linux/stat.h>
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#include <linux/mm.h>
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <linux/mount.h>
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#include <linux/init.h>
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#include <linux/idr.h>
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#include <linux/namei.h>
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#include <linux/bitops.h>
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#include <linux/spinlock.h>
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#include <linux/completion.h>
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#include <asm/uaccess.h>
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#include "internal.h"
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DEFINE_SPINLOCK(proc_subdir_lock);
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static int proc_match(unsigned int len, const char *name, struct proc_dir_entry *de)
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{
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if (de->namelen != len)
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return 0;
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return !memcmp(name, de->name, len);
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}
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/* buffer size is one page but our output routines use some slack for overruns */
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#define PROC_BLOCK_SIZE (PAGE_SIZE - 1024)
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static ssize_t
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__proc_file_read(struct file *file, char __user *buf, size_t nbytes,
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loff_t *ppos)
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{
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struct inode * inode = file->f_path.dentry->d_inode;
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char *page;
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ssize_t retval=0;
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int eof=0;
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ssize_t n, count;
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char *start;
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struct proc_dir_entry * dp;
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unsigned long long pos;
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/*
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* Gaah, please just use "seq_file" instead. The legacy /proc
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* interfaces cut loff_t down to off_t for reads, and ignore
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* the offset entirely for writes..
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*/
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pos = *ppos;
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if (pos > MAX_NON_LFS)
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return 0;
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if (nbytes > MAX_NON_LFS - pos)
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nbytes = MAX_NON_LFS - pos;
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dp = PDE(inode);
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if (!(page = (char*) __get_free_page(GFP_TEMPORARY)))
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return -ENOMEM;
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while ((nbytes > 0) && !eof) {
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count = min_t(size_t, PROC_BLOCK_SIZE, nbytes);
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start = NULL;
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if (dp->read_proc) {
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/*
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* How to be a proc read function
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* ------------------------------
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* Prototype:
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* int f(char *buffer, char **start, off_t offset,
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* int count, int *peof, void *dat)
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*
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* Assume that the buffer is "count" bytes in size.
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*
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* If you know you have supplied all the data you
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* have, set *peof.
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*
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* You have three ways to return data:
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* 0) Leave *start = NULL. (This is the default.)
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* Put the data of the requested offset at that
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* offset within the buffer. Return the number (n)
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* of bytes there are from the beginning of the
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* buffer up to the last byte of data. If the
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* number of supplied bytes (= n - offset) is
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* greater than zero and you didn't signal eof
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* and the reader is prepared to take more data
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* you will be called again with the requested
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* offset advanced by the number of bytes
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* absorbed. This interface is useful for files
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* no larger than the buffer.
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* 1) Set *start = an unsigned long value less than
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* the buffer address but greater than zero.
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* Put the data of the requested offset at the
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* beginning of the buffer. Return the number of
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* bytes of data placed there. If this number is
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* greater than zero and you didn't signal eof
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* and the reader is prepared to take more data
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* you will be called again with the requested
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* offset advanced by *start. This interface is
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* useful when you have a large file consisting
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* of a series of blocks which you want to count
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* and return as wholes.
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* (Hack by Paul.Russell@rustcorp.com.au)
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* 2) Set *start = an address within the buffer.
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* Put the data of the requested offset at *start.
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* Return the number of bytes of data placed there.
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* If this number is greater than zero and you
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* didn't signal eof and the reader is prepared to
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* take more data you will be called again with the
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* requested offset advanced by the number of bytes
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* absorbed.
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*/
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n = dp->read_proc(page, &start, *ppos,
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count, &eof, dp->data);
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} else
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break;
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if (n == 0) /* end of file */
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break;
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if (n < 0) { /* error */
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if (retval == 0)
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retval = n;
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break;
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}
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if (start == NULL) {
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if (n > PAGE_SIZE) {
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printk(KERN_ERR
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"proc_file_read: Apparent buffer overflow!\n");
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n = PAGE_SIZE;
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}
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n -= *ppos;
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if (n <= 0)
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break;
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if (n > count)
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n = count;
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start = page + *ppos;
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} else if (start < page) {
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if (n > PAGE_SIZE) {
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printk(KERN_ERR
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"proc_file_read: Apparent buffer overflow!\n");
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n = PAGE_SIZE;
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}
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if (n > count) {
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/*
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* Don't reduce n because doing so might
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* cut off part of a data block.
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*/
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printk(KERN_WARNING
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"proc_file_read: Read count exceeded\n");
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}
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} else /* start >= page */ {
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unsigned long startoff = (unsigned long)(start - page);
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if (n > (PAGE_SIZE - startoff)) {
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printk(KERN_ERR
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"proc_file_read: Apparent buffer overflow!\n");
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n = PAGE_SIZE - startoff;
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}
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if (n > count)
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n = count;
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}
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n -= copy_to_user(buf, start < page ? page : start, n);
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if (n == 0) {
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if (retval == 0)
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retval = -EFAULT;
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break;
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}
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*ppos += start < page ? (unsigned long)start : n;
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nbytes -= n;
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buf += n;
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retval += n;
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}
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free_page((unsigned long) page);
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return retval;
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}
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static ssize_t
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proc_file_read(struct file *file, char __user *buf, size_t nbytes,
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loff_t *ppos)
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{
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struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
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ssize_t rv = -EIO;
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spin_lock(&pde->pde_unload_lock);
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if (!pde->proc_fops) {
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spin_unlock(&pde->pde_unload_lock);
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return rv;
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}
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pde->pde_users++;
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spin_unlock(&pde->pde_unload_lock);
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rv = __proc_file_read(file, buf, nbytes, ppos);
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pde_users_dec(pde);
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return rv;
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}
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static ssize_t
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proc_file_write(struct file *file, const char __user *buffer,
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size_t count, loff_t *ppos)
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{
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struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
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ssize_t rv = -EIO;
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if (pde->write_proc) {
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spin_lock(&pde->pde_unload_lock);
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if (!pde->proc_fops) {
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spin_unlock(&pde->pde_unload_lock);
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return rv;
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}
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pde->pde_users++;
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spin_unlock(&pde->pde_unload_lock);
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/* FIXME: does this routine need ppos? probably... */
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rv = pde->write_proc(file, buffer, count, pde->data);
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pde_users_dec(pde);
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}
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return rv;
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}
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static loff_t
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proc_file_lseek(struct file *file, loff_t offset, int orig)
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{
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loff_t retval = -EINVAL;
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switch (orig) {
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case 1:
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offset += file->f_pos;
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/* fallthrough */
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case 0:
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if (offset < 0 || offset > MAX_NON_LFS)
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break;
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file->f_pos = retval = offset;
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}
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return retval;
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}
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static const struct file_operations proc_file_operations = {
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.llseek = proc_file_lseek,
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.read = proc_file_read,
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.write = proc_file_write,
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};
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static int proc_notify_change(struct dentry *dentry, struct iattr *iattr)
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{
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struct inode *inode = dentry->d_inode;
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struct proc_dir_entry *de = PDE(inode);
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int error;
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error = inode_change_ok(inode, iattr);
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if (error)
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return error;
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if ((iattr->ia_valid & ATTR_SIZE) &&
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iattr->ia_size != i_size_read(inode)) {
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error = vmtruncate(inode, iattr->ia_size);
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if (error)
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return error;
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}
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setattr_copy(inode, iattr);
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mark_inode_dirty(inode);
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de->uid = inode->i_uid;
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de->gid = inode->i_gid;
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de->mode = inode->i_mode;
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return 0;
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}
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static int proc_getattr(struct vfsmount *mnt, struct dentry *dentry,
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struct kstat *stat)
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{
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struct inode *inode = dentry->d_inode;
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struct proc_dir_entry *de = PROC_I(inode)->pde;
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if (de && de->nlink)
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inode->i_nlink = de->nlink;
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generic_fillattr(inode, stat);
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return 0;
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}
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static const struct inode_operations proc_file_inode_operations = {
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.setattr = proc_notify_change,
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};
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/*
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* This function parses a name such as "tty/driver/serial", and
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* returns the struct proc_dir_entry for "/proc/tty/driver", and
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* returns "serial" in residual.
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*/
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static int __xlate_proc_name(const char *name, struct proc_dir_entry **ret,
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const char **residual)
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{
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const char *cp = name, *next;
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struct proc_dir_entry *de;
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unsigned int len;
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de = *ret;
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if (!de)
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de = &proc_root;
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while (1) {
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next = strchr(cp, '/');
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if (!next)
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break;
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len = next - cp;
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for (de = de->subdir; de ; de = de->next) {
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if (proc_match(len, cp, de))
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break;
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}
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if (!de) {
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WARN(1, "name '%s'\n", name);
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return -ENOENT;
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}
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cp += len + 1;
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}
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*residual = cp;
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*ret = de;
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return 0;
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}
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static int xlate_proc_name(const char *name, struct proc_dir_entry **ret,
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const char **residual)
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{
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int rv;
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spin_lock(&proc_subdir_lock);
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rv = __xlate_proc_name(name, ret, residual);
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spin_unlock(&proc_subdir_lock);
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return rv;
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}
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static DEFINE_IDA(proc_inum_ida);
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static DEFINE_SPINLOCK(proc_inum_lock); /* protects the above */
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#define PROC_DYNAMIC_FIRST 0xF0000000U
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/*
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* Return an inode number between PROC_DYNAMIC_FIRST and
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* 0xffffffff, or zero on failure.
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*/
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static unsigned int get_inode_number(void)
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{
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unsigned int i;
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int error;
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retry:
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if (ida_pre_get(&proc_inum_ida, GFP_KERNEL) == 0)
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return 0;
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spin_lock(&proc_inum_lock);
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error = ida_get_new(&proc_inum_ida, &i);
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spin_unlock(&proc_inum_lock);
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if (error == -EAGAIN)
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goto retry;
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else if (error)
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return 0;
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if (i > UINT_MAX - PROC_DYNAMIC_FIRST) {
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spin_lock(&proc_inum_lock);
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ida_remove(&proc_inum_ida, i);
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spin_unlock(&proc_inum_lock);
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return 0;
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}
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return PROC_DYNAMIC_FIRST + i;
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}
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static void release_inode_number(unsigned int inum)
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{
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spin_lock(&proc_inum_lock);
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ida_remove(&proc_inum_ida, inum - PROC_DYNAMIC_FIRST);
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spin_unlock(&proc_inum_lock);
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}
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static void *proc_follow_link(struct dentry *dentry, struct nameidata *nd)
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{
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nd_set_link(nd, PDE(dentry->d_inode)->data);
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return NULL;
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}
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static const struct inode_operations proc_link_inode_operations = {
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.readlink = generic_readlink,
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.follow_link = proc_follow_link,
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};
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/*
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* As some entries in /proc are volatile, we want to
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* get rid of unused dentries. This could be made
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* smarter: we could keep a "volatile" flag in the
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* inode to indicate which ones to keep.
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*/
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static int proc_delete_dentry(const struct dentry * dentry)
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{
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return 1;
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}
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static const struct dentry_operations proc_dentry_operations =
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{
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.d_delete = proc_delete_dentry,
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};
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/*
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* Don't create negative dentries here, return -ENOENT by hand
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* instead.
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*/
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struct dentry *proc_lookup_de(struct proc_dir_entry *de, struct inode *dir,
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struct dentry *dentry)
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{
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struct inode *inode = NULL;
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int error = -ENOENT;
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spin_lock(&proc_subdir_lock);
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for (de = de->subdir; de ; de = de->next) {
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if (de->namelen != dentry->d_name.len)
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continue;
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if (!memcmp(dentry->d_name.name, de->name, de->namelen)) {
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pde_get(de);
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spin_unlock(&proc_subdir_lock);
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error = -EINVAL;
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inode = proc_get_inode(dir->i_sb, de);
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goto out_unlock;
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}
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}
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spin_unlock(&proc_subdir_lock);
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out_unlock:
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if (inode) {
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d_set_d_op(dentry, &proc_dentry_operations);
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d_add(dentry, inode);
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return NULL;
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}
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if (de)
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pde_put(de);
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return ERR_PTR(error);
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}
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struct dentry *proc_lookup(struct inode *dir, struct dentry *dentry,
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struct nameidata *nd)
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{
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return proc_lookup_de(PDE(dir), dir, dentry);
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}
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/*
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* This returns non-zero if at EOF, so that the /proc
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* root directory can use this and check if it should
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* continue with the <pid> entries..
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*
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* Note that the VFS-layer doesn't care about the return
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* value of the readdir() call, as long as it's non-negative
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* for success..
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*/
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int proc_readdir_de(struct proc_dir_entry *de, struct file *filp, void *dirent,
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filldir_t filldir)
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{
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unsigned int ino;
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int i;
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struct inode *inode = filp->f_path.dentry->d_inode;
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int ret = 0;
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ino = inode->i_ino;
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i = filp->f_pos;
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switch (i) {
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case 0:
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if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
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goto out;
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i++;
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filp->f_pos++;
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/* fall through */
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case 1:
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if (filldir(dirent, "..", 2, i,
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parent_ino(filp->f_path.dentry),
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DT_DIR) < 0)
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goto out;
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i++;
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filp->f_pos++;
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/* fall through */
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default:
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spin_lock(&proc_subdir_lock);
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de = de->subdir;
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i -= 2;
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for (;;) {
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if (!de) {
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ret = 1;
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spin_unlock(&proc_subdir_lock);
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goto out;
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}
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if (!i)
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break;
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de = de->next;
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i--;
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}
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do {
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struct proc_dir_entry *next;
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/* filldir passes info to user space */
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pde_get(de);
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spin_unlock(&proc_subdir_lock);
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if (filldir(dirent, de->name, de->namelen, filp->f_pos,
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de->low_ino, de->mode >> 12) < 0) {
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pde_put(de);
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goto out;
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}
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spin_lock(&proc_subdir_lock);
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filp->f_pos++;
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next = de->next;
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pde_put(de);
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de = next;
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} while (de);
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spin_unlock(&proc_subdir_lock);
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}
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ret = 1;
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out:
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return ret;
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}
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|
|
int proc_readdir(struct file *filp, void *dirent, filldir_t filldir)
|
|
{
|
|
struct inode *inode = filp->f_path.dentry->d_inode;
|
|
|
|
return proc_readdir_de(PDE(inode), filp, dirent, filldir);
|
|
}
|
|
|
|
/*
|
|
* These are the generic /proc directory operations. They
|
|
* use the in-memory "struct proc_dir_entry" tree to parse
|
|
* the /proc directory.
|
|
*/
|
|
static const struct file_operations proc_dir_operations = {
|
|
.llseek = generic_file_llseek,
|
|
.read = generic_read_dir,
|
|
.readdir = proc_readdir,
|
|
};
|
|
|
|
/*
|
|
* proc directories can do almost nothing..
|
|
*/
|
|
static const struct inode_operations proc_dir_inode_operations = {
|
|
.lookup = proc_lookup,
|
|
.getattr = proc_getattr,
|
|
.setattr = proc_notify_change,
|
|
};
|
|
|
|
static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp)
|
|
{
|
|
unsigned int i;
|
|
struct proc_dir_entry *tmp;
|
|
|
|
i = get_inode_number();
|
|
if (i == 0)
|
|
return -EAGAIN;
|
|
dp->low_ino = i;
|
|
|
|
if (S_ISDIR(dp->mode)) {
|
|
if (dp->proc_iops == NULL) {
|
|
dp->proc_fops = &proc_dir_operations;
|
|
dp->proc_iops = &proc_dir_inode_operations;
|
|
}
|
|
dir->nlink++;
|
|
} else if (S_ISLNK(dp->mode)) {
|
|
if (dp->proc_iops == NULL)
|
|
dp->proc_iops = &proc_link_inode_operations;
|
|
} else if (S_ISREG(dp->mode)) {
|
|
if (dp->proc_fops == NULL)
|
|
dp->proc_fops = &proc_file_operations;
|
|
if (dp->proc_iops == NULL)
|
|
dp->proc_iops = &proc_file_inode_operations;
|
|
}
|
|
|
|
spin_lock(&proc_subdir_lock);
|
|
|
|
for (tmp = dir->subdir; tmp; tmp = tmp->next)
|
|
if (strcmp(tmp->name, dp->name) == 0) {
|
|
WARN(1, KERN_WARNING "proc_dir_entry '%s/%s' already registered\n",
|
|
dir->name, dp->name);
|
|
break;
|
|
}
|
|
|
|
dp->next = dir->subdir;
|
|
dp->parent = dir;
|
|
dir->subdir = dp;
|
|
spin_unlock(&proc_subdir_lock);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent,
|
|
const char *name,
|
|
mode_t mode,
|
|
nlink_t nlink)
|
|
{
|
|
struct proc_dir_entry *ent = NULL;
|
|
const char *fn = name;
|
|
unsigned int len;
|
|
|
|
/* make sure name is valid */
|
|
if (!name || !strlen(name)) goto out;
|
|
|
|
if (xlate_proc_name(name, parent, &fn) != 0)
|
|
goto out;
|
|
|
|
/* At this point there must not be any '/' characters beyond *fn */
|
|
if (strchr(fn, '/'))
|
|
goto out;
|
|
|
|
len = strlen(fn);
|
|
|
|
ent = kmalloc(sizeof(struct proc_dir_entry) + len + 1, GFP_KERNEL);
|
|
if (!ent) goto out;
|
|
|
|
memset(ent, 0, sizeof(struct proc_dir_entry));
|
|
memcpy(ent->name, fn, len + 1);
|
|
ent->namelen = len;
|
|
ent->mode = mode;
|
|
ent->nlink = nlink;
|
|
atomic_set(&ent->count, 1);
|
|
ent->pde_users = 0;
|
|
spin_lock_init(&ent->pde_unload_lock);
|
|
ent->pde_unload_completion = NULL;
|
|
INIT_LIST_HEAD(&ent->pde_openers);
|
|
out:
|
|
return ent;
|
|
}
|
|
|
|
struct proc_dir_entry *proc_symlink(const char *name,
|
|
struct proc_dir_entry *parent, const char *dest)
|
|
{
|
|
struct proc_dir_entry *ent;
|
|
|
|
ent = __proc_create(&parent, name,
|
|
(S_IFLNK | S_IRUGO | S_IWUGO | S_IXUGO),1);
|
|
|
|
if (ent) {
|
|
ent->data = kmalloc((ent->size=strlen(dest))+1, GFP_KERNEL);
|
|
if (ent->data) {
|
|
strcpy((char*)ent->data,dest);
|
|
if (proc_register(parent, ent) < 0) {
|
|
kfree(ent->data);
|
|
kfree(ent);
|
|
ent = NULL;
|
|
}
|
|
} else {
|
|
kfree(ent);
|
|
ent = NULL;
|
|
}
|
|
}
|
|
return ent;
|
|
}
|
|
EXPORT_SYMBOL(proc_symlink);
|
|
|
|
struct proc_dir_entry *proc_mkdir_mode(const char *name, mode_t mode,
|
|
struct proc_dir_entry *parent)
|
|
{
|
|
struct proc_dir_entry *ent;
|
|
|
|
ent = __proc_create(&parent, name, S_IFDIR | mode, 2);
|
|
if (ent) {
|
|
if (proc_register(parent, ent) < 0) {
|
|
kfree(ent);
|
|
ent = NULL;
|
|
}
|
|
}
|
|
return ent;
|
|
}
|
|
EXPORT_SYMBOL(proc_mkdir_mode);
|
|
|
|
struct proc_dir_entry *proc_net_mkdir(struct net *net, const char *name,
|
|
struct proc_dir_entry *parent)
|
|
{
|
|
struct proc_dir_entry *ent;
|
|
|
|
ent = __proc_create(&parent, name, S_IFDIR | S_IRUGO | S_IXUGO, 2);
|
|
if (ent) {
|
|
ent->data = net;
|
|
if (proc_register(parent, ent) < 0) {
|
|
kfree(ent);
|
|
ent = NULL;
|
|
}
|
|
}
|
|
return ent;
|
|
}
|
|
EXPORT_SYMBOL_GPL(proc_net_mkdir);
|
|
|
|
struct proc_dir_entry *proc_mkdir(const char *name,
|
|
struct proc_dir_entry *parent)
|
|
{
|
|
return proc_mkdir_mode(name, S_IRUGO | S_IXUGO, parent);
|
|
}
|
|
EXPORT_SYMBOL(proc_mkdir);
|
|
|
|
struct proc_dir_entry *create_proc_entry(const char *name, mode_t mode,
|
|
struct proc_dir_entry *parent)
|
|
{
|
|
struct proc_dir_entry *ent;
|
|
nlink_t nlink;
|
|
|
|
if (S_ISDIR(mode)) {
|
|
if ((mode & S_IALLUGO) == 0)
|
|
mode |= S_IRUGO | S_IXUGO;
|
|
nlink = 2;
|
|
} else {
|
|
if ((mode & S_IFMT) == 0)
|
|
mode |= S_IFREG;
|
|
if ((mode & S_IALLUGO) == 0)
|
|
mode |= S_IRUGO;
|
|
nlink = 1;
|
|
}
|
|
|
|
ent = __proc_create(&parent, name, mode, nlink);
|
|
if (ent) {
|
|
if (proc_register(parent, ent) < 0) {
|
|
kfree(ent);
|
|
ent = NULL;
|
|
}
|
|
}
|
|
return ent;
|
|
}
|
|
EXPORT_SYMBOL(create_proc_entry);
|
|
|
|
struct proc_dir_entry *proc_create_data(const char *name, mode_t mode,
|
|
struct proc_dir_entry *parent,
|
|
const struct file_operations *proc_fops,
|
|
void *data)
|
|
{
|
|
struct proc_dir_entry *pde;
|
|
nlink_t nlink;
|
|
|
|
if (S_ISDIR(mode)) {
|
|
if ((mode & S_IALLUGO) == 0)
|
|
mode |= S_IRUGO | S_IXUGO;
|
|
nlink = 2;
|
|
} else {
|
|
if ((mode & S_IFMT) == 0)
|
|
mode |= S_IFREG;
|
|
if ((mode & S_IALLUGO) == 0)
|
|
mode |= S_IRUGO;
|
|
nlink = 1;
|
|
}
|
|
|
|
pde = __proc_create(&parent, name, mode, nlink);
|
|
if (!pde)
|
|
goto out;
|
|
pde->proc_fops = proc_fops;
|
|
pde->data = data;
|
|
if (proc_register(parent, pde) < 0)
|
|
goto out_free;
|
|
return pde;
|
|
out_free:
|
|
kfree(pde);
|
|
out:
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL(proc_create_data);
|
|
|
|
static void free_proc_entry(struct proc_dir_entry *de)
|
|
{
|
|
release_inode_number(de->low_ino);
|
|
|
|
if (S_ISLNK(de->mode))
|
|
kfree(de->data);
|
|
kfree(de);
|
|
}
|
|
|
|
void pde_put(struct proc_dir_entry *pde)
|
|
{
|
|
if (atomic_dec_and_test(&pde->count))
|
|
free_proc_entry(pde);
|
|
}
|
|
|
|
/*
|
|
* Remove a /proc entry and free it if it's not currently in use.
|
|
*/
|
|
void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
|
|
{
|
|
struct proc_dir_entry **p;
|
|
struct proc_dir_entry *de = NULL;
|
|
const char *fn = name;
|
|
unsigned int len;
|
|
|
|
spin_lock(&proc_subdir_lock);
|
|
if (__xlate_proc_name(name, &parent, &fn) != 0) {
|
|
spin_unlock(&proc_subdir_lock);
|
|
return;
|
|
}
|
|
len = strlen(fn);
|
|
|
|
for (p = &parent->subdir; *p; p=&(*p)->next ) {
|
|
if (proc_match(len, fn, *p)) {
|
|
de = *p;
|
|
*p = de->next;
|
|
de->next = NULL;
|
|
break;
|
|
}
|
|
}
|
|
spin_unlock(&proc_subdir_lock);
|
|
if (!de) {
|
|
WARN(1, "name '%s'\n", name);
|
|
return;
|
|
}
|
|
|
|
spin_lock(&de->pde_unload_lock);
|
|
/*
|
|
* Stop accepting new callers into module. If you're
|
|
* dynamically allocating ->proc_fops, save a pointer somewhere.
|
|
*/
|
|
de->proc_fops = NULL;
|
|
/* Wait until all existing callers into module are done. */
|
|
if (de->pde_users > 0) {
|
|
DECLARE_COMPLETION_ONSTACK(c);
|
|
|
|
if (!de->pde_unload_completion)
|
|
de->pde_unload_completion = &c;
|
|
|
|
spin_unlock(&de->pde_unload_lock);
|
|
|
|
wait_for_completion(de->pde_unload_completion);
|
|
|
|
spin_lock(&de->pde_unload_lock);
|
|
}
|
|
|
|
while (!list_empty(&de->pde_openers)) {
|
|
struct pde_opener *pdeo;
|
|
|
|
pdeo = list_first_entry(&de->pde_openers, struct pde_opener, lh);
|
|
list_del(&pdeo->lh);
|
|
spin_unlock(&de->pde_unload_lock);
|
|
pdeo->release(pdeo->inode, pdeo->file);
|
|
kfree(pdeo);
|
|
spin_lock(&de->pde_unload_lock);
|
|
}
|
|
spin_unlock(&de->pde_unload_lock);
|
|
|
|
if (S_ISDIR(de->mode))
|
|
parent->nlink--;
|
|
de->nlink = 0;
|
|
WARN(de->subdir, KERN_WARNING "%s: removing non-empty directory "
|
|
"'%s/%s', leaking at least '%s'\n", __func__,
|
|
de->parent->name, de->name, de->subdir->name);
|
|
pde_put(de);
|
|
}
|
|
EXPORT_SYMBOL(remove_proc_entry);
|