blob: 28955d4b7218e95a6ba7666111459b0382450786 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/proc/inode.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
7#include <linux/time.h>
8#include <linux/proc_fs.h>
9#include <linux/kernel.h>
Vasiliy Kulikov97412952012-01-10 15:11:27 -080010#include <linux/pid_namespace.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#include <linux/mm.h>
12#include <linux/string.h>
13#include <linux/stat.h>
Alexey Dobriyan786d7e12007-07-15 23:39:00 -070014#include <linux/completion.h>
Alexey Dobriyandd23aae2007-09-11 15:23:55 -070015#include <linux/poll.h>
Andrew Morton87ebdc02013-02-27 17:03:16 -080016#include <linux/printk.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/file.h>
18#include <linux/limits.h>
19#include <linux/init.h>
20#include <linux/module.h>
Al Viro9043476f2008-07-15 08:54:06 -040021#include <linux/sysctl.h>
Vasiliy Kulikov97412952012-01-10 15:11:27 -080022#include <linux/seq_file.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090023#include <linux/slab.h>
Vasiliy Kulikov97412952012-01-10 15:11:27 -080024#include <linux/mount.h>
David Howells303eb7e2013-04-11 23:55:54 +010025#include <linux/magic.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <asm/uaccess.h>
28
Adrian Bunkfee781e2006-01-08 01:04:16 -080029#include "internal.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070030
Al Viro82679522010-06-04 22:17:56 -040031static void proc_evict_inode(struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -070032{
33 struct proc_dir_entry *de;
Al Virodfef6dcd32011-03-08 01:25:28 -050034 struct ctl_table_header *head;
Eric W. Biederman6b4e3062010-03-07 16:41:34 -080035 const struct proc_ns_operations *ns_ops;
Eric W. Biedermanbf056bf2011-06-18 17:48:18 -070036 void *ns;
Linus Torvalds1da177e2005-04-16 15:20:36 -070037
Mark Fashehfef26652005-09-09 13:01:31 -070038 truncate_inode_pages(&inode->i_data, 0);
Jan Karadbd57682012-05-03 14:48:02 +020039 clear_inode(inode);
Mark Fashehfef26652005-09-09 13:01:31 -070040
Eric W. Biederman99f89552006-06-26 00:25:55 -070041 /* Stop tracking associated processes */
Eric W. Biederman13b41b02006-06-26 00:25:56 -070042 put_pid(PROC_I(inode)->pid);
Linus Torvalds1da177e2005-04-16 15:20:36 -070043
44 /* Let go of any associated proc directory entry */
45 de = PROC_I(inode)->pde;
Alexey Dobriyan99b76232009-03-25 22:48:06 +030046 if (de)
Alexey Dobriyan135d5652009-12-15 16:45:39 -080047 pde_put(de);
Al Virodfef6dcd32011-03-08 01:25:28 -050048 head = PROC_I(inode)->sysctl;
49 if (head) {
50 rcu_assign_pointer(PROC_I(inode)->sysctl, NULL);
51 sysctl_head_put(head);
52 }
Eric W. Biederman6b4e3062010-03-07 16:41:34 -080053 /* Release any associated namespace */
David Howells0bb80f22013-04-12 01:50:06 +010054 ns_ops = PROC_I(inode)->ns.ns_ops;
55 ns = PROC_I(inode)->ns.ns;
Eric W. Biedermanbf056bf2011-06-18 17:48:18 -070056 if (ns_ops && ns)
57 ns_ops->put(ns);
Linus Torvalds1da177e2005-04-16 15:20:36 -070058}
59
Christoph Lametere18b8902006-12-06 20:33:20 -080060static struct kmem_cache * proc_inode_cachep;
Linus Torvalds1da177e2005-04-16 15:20:36 -070061
62static struct inode *proc_alloc_inode(struct super_block *sb)
63{
64 struct proc_inode *ei;
65 struct inode *inode;
66
Christoph Lametere94b1762006-12-06 20:33:17 -080067 ei = (struct proc_inode *)kmem_cache_alloc(proc_inode_cachep, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070068 if (!ei)
69 return NULL;
Eric W. Biederman13b41b02006-06-26 00:25:56 -070070 ei->pid = NULL;
Eric W. Biedermanaed7a6c2006-06-26 00:25:44 -070071 ei->fd = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 ei->op.proc_get_link = NULL;
73 ei->pde = NULL;
Al Viro9043476f2008-07-15 08:54:06 -040074 ei->sysctl = NULL;
75 ei->sysctl_entry = NULL;
David Howells0bb80f22013-04-12 01:50:06 +010076 ei->ns.ns = NULL;
77 ei->ns.ns_ops = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -070078 inode = &ei->vfs_inode;
79 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
80 return inode;
81}
82
Nick Pigginfa0d7e3d2011-01-07 17:49:49 +110083static void proc_i_callback(struct rcu_head *head)
84{
85 struct inode *inode = container_of(head, struct inode, i_rcu);
Nick Pigginfa0d7e3d2011-01-07 17:49:49 +110086 kmem_cache_free(proc_inode_cachep, PROC_I(inode));
87}
88
Linus Torvalds1da177e2005-04-16 15:20:36 -070089static void proc_destroy_inode(struct inode *inode)
90{
Nick Pigginfa0d7e3d2011-01-07 17:49:49 +110091 call_rcu(&inode->i_rcu, proc_i_callback);
Linus Torvalds1da177e2005-04-16 15:20:36 -070092}
93
Alexey Dobriyan51cc5062008-07-25 19:45:34 -070094static void init_once(void *foo)
Linus Torvalds1da177e2005-04-16 15:20:36 -070095{
96 struct proc_inode *ei = (struct proc_inode *) foo;
97
Christoph Lametera35afb82007-05-16 22:10:57 -070098 inode_init_once(&ei->vfs_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099}
Paul Mundt20c2df82007-07-20 10:11:58 +0900100
Alexey Dobriyan5bcd7ff2008-10-17 03:43:55 +0400101void __init proc_init_inodecache(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102{
103 proc_inode_cachep = kmem_cache_create("proc_inode_cache",
104 sizeof(struct proc_inode),
Paul Jacksonfffb60f2006-03-24 03:16:06 -0800105 0, (SLAB_RECLAIM_ACCOUNT|
Alexey Dobriyan040b5c62007-10-16 23:26:10 -0700106 SLAB_MEM_SPREAD|SLAB_PANIC),
Paul Mundt20c2df82007-07-20 10:11:58 +0900107 init_once);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108}
109
Vasiliy Kulikov97412952012-01-10 15:11:27 -0800110static int proc_show_options(struct seq_file *seq, struct dentry *root)
111{
Vasiliy Kulikov04996802012-01-10 15:11:31 -0800112 struct super_block *sb = root->d_sb;
113 struct pid_namespace *pid = sb->s_fs_info;
114
Eric W. Biedermandcb0f222012-02-09 08:48:21 -0800115 if (!gid_eq(pid->pid_gid, GLOBAL_ROOT_GID))
116 seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, pid->pid_gid));
Vasiliy Kulikov04996802012-01-10 15:11:31 -0800117 if (pid->hide_pid != 0)
118 seq_printf(seq, ",hidepid=%u", pid->hide_pid);
119
Vasiliy Kulikov97412952012-01-10 15:11:27 -0800120 return 0;
121}
122
Josef 'Jeff' Sipekee9b6d62007-02-12 00:55:41 -0800123static const struct super_operations proc_sops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124 .alloc_inode = proc_alloc_inode,
125 .destroy_inode = proc_destroy_inode,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126 .drop_inode = generic_delete_inode,
Al Viro82679522010-06-04 22:17:56 -0400127 .evict_inode = proc_evict_inode,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 .statfs = simple_statfs,
Vasiliy Kulikov97412952012-01-10 15:11:27 -0800129 .remount_fs = proc_remount,
130 .show_options = proc_show_options,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131};
132
Al Viro866ad9a2013-04-03 19:07:30 -0400133enum {BIAS = -1U<<31};
134
135static inline int use_pde(struct proc_dir_entry *pde)
136{
Al Viro05c0ae22013-04-04 16:28:47 -0400137 return atomic_inc_unless_negative(&pde->in_use);
Alexey Dobriyan881adb82008-07-25 01:48:29 -0700138}
139
Al Viro866ad9a2013-04-03 19:07:30 -0400140static void unuse_pde(struct proc_dir_entry *pde)
Alexey Dobriyan881adb82008-07-25 01:48:29 -0700141{
Al Viro05c0ae22013-04-04 16:28:47 -0400142 if (atomic_dec_return(&pde->in_use) == BIAS)
143 complete(pde->pde_unload_completion);
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700144}
145
Al Viroca469f32013-04-03 19:57:00 -0400146/* pde is locked */
147static void close_pdeo(struct proc_dir_entry *pde, struct pde_opener *pdeo)
148{
Al Viro05c0ae22013-04-04 16:28:47 -0400149 if (pdeo->closing) {
Al Viroca469f32013-04-03 19:57:00 -0400150 /* somebody else is doing that, just wait */
Al Viro05c0ae22013-04-04 16:28:47 -0400151 DECLARE_COMPLETION_ONSTACK(c);
152 pdeo->c = &c;
Al Viroca469f32013-04-03 19:57:00 -0400153 spin_unlock(&pde->pde_unload_lock);
Al Viro05c0ae22013-04-04 16:28:47 -0400154 wait_for_completion(&c);
Al Viroca469f32013-04-03 19:57:00 -0400155 spin_lock(&pde->pde_unload_lock);
Al Viroca469f32013-04-03 19:57:00 -0400156 } else {
157 struct file *file;
Al Viro05c0ae22013-04-04 16:28:47 -0400158 pdeo->closing = 1;
Al Viroca469f32013-04-03 19:57:00 -0400159 spin_unlock(&pde->pde_unload_lock);
160 file = pdeo->file;
161 pde->proc_fops->release(file_inode(file), file);
162 spin_lock(&pde->pde_unload_lock);
163 list_del_init(&pdeo->lh);
Al Viro05c0ae22013-04-04 16:28:47 -0400164 if (pdeo->c)
165 complete(pdeo->c);
Al Viroca469f32013-04-03 19:57:00 -0400166 kfree(pdeo);
Al Viro05c0ae22013-04-04 16:28:47 -0400167 }
Al Viroca469f32013-04-03 19:57:00 -0400168}
169
Al Viro866ad9a2013-04-03 19:07:30 -0400170void proc_entry_rundown(struct proc_dir_entry *de)
171{
Al Viro05c0ae22013-04-04 16:28:47 -0400172 DECLARE_COMPLETION_ONSTACK(c);
Al Viro866ad9a2013-04-03 19:07:30 -0400173 /* Wait until all existing callers into module are done. */
Al Viro05c0ae22013-04-04 16:28:47 -0400174 de->pde_unload_completion = &c;
175 if (atomic_add_return(BIAS, &de->in_use) != BIAS)
176 wait_for_completion(&c);
Al Viro866ad9a2013-04-03 19:07:30 -0400177
Al Viro05c0ae22013-04-04 16:28:47 -0400178 spin_lock(&de->pde_unload_lock);
Al Viro866ad9a2013-04-03 19:07:30 -0400179 while (!list_empty(&de->pde_openers)) {
180 struct pde_opener *pdeo;
Al Viro866ad9a2013-04-03 19:07:30 -0400181 pdeo = list_first_entry(&de->pde_openers, struct pde_opener, lh);
Al Viroca469f32013-04-03 19:57:00 -0400182 close_pdeo(de, pdeo);
Al Viro866ad9a2013-04-03 19:07:30 -0400183 }
184 spin_unlock(&de->pde_unload_lock);
185}
186
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700187static loff_t proc_reg_llseek(struct file *file, loff_t offset, int whence)
188{
Al Viro496ad9a2013-01-23 17:07:38 -0500189 struct proc_dir_entry *pde = PDE(file_inode(file));
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700190 loff_t rv = -EINVAL;
Al Viro866ad9a2013-04-03 19:07:30 -0400191 if (use_pde(pde)) {
192 loff_t (*llseek)(struct file *, loff_t, int);
193 llseek = pde->proc_fops->llseek;
194 if (!llseek)
195 llseek = default_llseek;
196 rv = llseek(file, offset, whence);
197 unuse_pde(pde);
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700198 }
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700199 return rv;
200}
201
202static ssize_t proc_reg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
203{
Al Viro866ad9a2013-04-03 19:07:30 -0400204 ssize_t (*read)(struct file *, char __user *, size_t, loff_t *);
Al Viro496ad9a2013-01-23 17:07:38 -0500205 struct proc_dir_entry *pde = PDE(file_inode(file));
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700206 ssize_t rv = -EIO;
Al Viro866ad9a2013-04-03 19:07:30 -0400207 if (use_pde(pde)) {
208 read = pde->proc_fops->read;
209 if (read)
210 rv = read(file, buf, count, ppos);
211 unuse_pde(pde);
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700212 }
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700213 return rv;
214}
215
216static ssize_t proc_reg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
217{
Al Viro866ad9a2013-04-03 19:07:30 -0400218 ssize_t (*write)(struct file *, const char __user *, size_t, loff_t *);
Al Viro496ad9a2013-01-23 17:07:38 -0500219 struct proc_dir_entry *pde = PDE(file_inode(file));
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700220 ssize_t rv = -EIO;
Al Viro866ad9a2013-04-03 19:07:30 -0400221 if (use_pde(pde)) {
222 write = pde->proc_fops->write;
223 if (write)
224 rv = write(file, buf, count, ppos);
225 unuse_pde(pde);
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700226 }
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700227 return rv;
228}
229
230static unsigned int proc_reg_poll(struct file *file, struct poll_table_struct *pts)
231{
Al Viro496ad9a2013-01-23 17:07:38 -0500232 struct proc_dir_entry *pde = PDE(file_inode(file));
Alexey Dobriyandd23aae2007-09-11 15:23:55 -0700233 unsigned int rv = DEFAULT_POLLMASK;
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700234 unsigned int (*poll)(struct file *, struct poll_table_struct *);
Al Viro866ad9a2013-04-03 19:07:30 -0400235 if (use_pde(pde)) {
236 poll = pde->proc_fops->poll;
237 if (poll)
238 rv = poll(file, pts);
239 unuse_pde(pde);
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700240 }
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700241 return rv;
242}
243
244static long proc_reg_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
245{
Al Viro496ad9a2013-01-23 17:07:38 -0500246 struct proc_dir_entry *pde = PDE(file_inode(file));
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700247 long rv = -ENOTTY;
Arnd Bergmannb19dd422010-07-04 00:15:10 +0200248 long (*ioctl)(struct file *, unsigned int, unsigned long);
Al Viro866ad9a2013-04-03 19:07:30 -0400249 if (use_pde(pde)) {
250 ioctl = pde->proc_fops->unlocked_ioctl;
251 if (ioctl)
252 rv = ioctl(file, cmd, arg);
253 unuse_pde(pde);
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700254 }
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700255 return rv;
256}
257
258#ifdef CONFIG_COMPAT
259static long proc_reg_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
260{
Al Viro496ad9a2013-01-23 17:07:38 -0500261 struct proc_dir_entry *pde = PDE(file_inode(file));
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700262 long rv = -ENOTTY;
263 long (*compat_ioctl)(struct file *, unsigned int, unsigned long);
Al Viro866ad9a2013-04-03 19:07:30 -0400264 if (use_pde(pde)) {
265 compat_ioctl = pde->proc_fops->compat_ioctl;
266 if (compat_ioctl)
267 rv = compat_ioctl(file, cmd, arg);
268 unuse_pde(pde);
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700269 }
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700270 return rv;
271}
272#endif
273
274static int proc_reg_mmap(struct file *file, struct vm_area_struct *vma)
275{
Al Viro496ad9a2013-01-23 17:07:38 -0500276 struct proc_dir_entry *pde = PDE(file_inode(file));
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700277 int rv = -EIO;
278 int (*mmap)(struct file *, struct vm_area_struct *);
Al Viro866ad9a2013-04-03 19:07:30 -0400279 if (use_pde(pde)) {
280 mmap = pde->proc_fops->mmap;
281 if (mmap)
282 rv = mmap(file, vma);
283 unuse_pde(pde);
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700284 }
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700285 return rv;
286}
287
HATAYAMA Daisuke5721cf82013-11-12 15:11:15 -0800288static unsigned long
289proc_reg_get_unmapped_area(struct file *file, unsigned long orig_addr,
290 unsigned long len, unsigned long pgoff,
291 unsigned long flags)
Alexey Dobriyanc4fe2442013-08-20 22:17:24 +0300292{
293 struct proc_dir_entry *pde = PDE(file_inode(file));
HATAYAMA Daisuke2cbe3b02013-10-16 13:47:04 -0700294 unsigned long rv = -EIO;
HATAYAMA Daisuke5721cf82013-11-12 15:11:15 -0800295 unsigned long (*get_area)(struct file *, unsigned long, unsigned long,
296 unsigned long, unsigned long) = NULL;
Alexey Dobriyanc4fe2442013-08-20 22:17:24 +0300297 if (use_pde(pde)) {
HATAYAMA Daisukefad1a862013-10-16 13:47:05 -0700298#ifdef CONFIG_MMU
HATAYAMA Daisuke5721cf82013-11-12 15:11:15 -0800299 get_area = current->mm->get_unmapped_area;
HATAYAMA Daisukefad1a862013-10-16 13:47:05 -0700300#endif
301 if (pde->proc_fops->get_unmapped_area)
HATAYAMA Daisuke5721cf82013-11-12 15:11:15 -0800302 get_area = pde->proc_fops->get_unmapped_area;
303 if (get_area)
304 rv = get_area(file, orig_addr, len, pgoff, flags);
Alexey Dobriyanc4fe2442013-08-20 22:17:24 +0300305 unuse_pde(pde);
306 }
307 return rv;
308}
309
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700310static int proc_reg_open(struct inode *inode, struct file *file)
311{
312 struct proc_dir_entry *pde = PDE(inode);
313 int rv = 0;
314 int (*open)(struct inode *, struct file *);
Alexey Dobriyan881adb82008-07-25 01:48:29 -0700315 int (*release)(struct inode *, struct file *);
316 struct pde_opener *pdeo;
317
318 /*
319 * What for, you ask? Well, we can have open, rmmod, remove_proc_entry
320 * sequence. ->release won't be called because ->proc_fops will be
321 * cleared. Depending on complexity of ->release, consequences vary.
322 *
323 * We can't wait for mercy when close will be done for real, it's
324 * deadlockable: rmmod foo </proc/foo . So, we're going to do ->release
325 * by hand in remove_proc_entry(). For this, save opener's credentials
326 * for later.
327 */
Al Viro05c0ae22013-04-04 16:28:47 -0400328 pdeo = kzalloc(sizeof(struct pde_opener), GFP_KERNEL);
Alexey Dobriyan881adb82008-07-25 01:48:29 -0700329 if (!pdeo)
330 return -ENOMEM;
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700331
Al Viro866ad9a2013-04-03 19:07:30 -0400332 if (!use_pde(pde)) {
Alexey Dobriyan881adb82008-07-25 01:48:29 -0700333 kfree(pdeo);
Daisuke Oginod2857e72011-07-26 16:08:37 -0700334 return -ENOENT;
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700335 }
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700336 open = pde->proc_fops->open;
Alexey Dobriyan881adb82008-07-25 01:48:29 -0700337 release = pde->proc_fops->release;
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700338
339 if (open)
340 rv = open(inode, file);
341
Alexey Dobriyan881adb82008-07-25 01:48:29 -0700342 if (rv == 0 && release) {
343 /* To know what to release. */
Alexey Dobriyan881adb82008-07-25 01:48:29 -0700344 pdeo->file = file;
345 /* Strictly for "too late" ->release in proc_reg_release(). */
Al Viro05c0ae22013-04-04 16:28:47 -0400346 spin_lock(&pde->pde_unload_lock);
Alexey Dobriyan881adb82008-07-25 01:48:29 -0700347 list_add(&pdeo->lh, &pde->pde_openers);
Al Viro05c0ae22013-04-04 16:28:47 -0400348 spin_unlock(&pde->pde_unload_lock);
Alexey Dobriyan881adb82008-07-25 01:48:29 -0700349 } else
350 kfree(pdeo);
Al Viro05c0ae22013-04-04 16:28:47 -0400351
352 unuse_pde(pde);
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700353 return rv;
354}
355
356static int proc_reg_release(struct inode *inode, struct file *file)
357{
358 struct proc_dir_entry *pde = PDE(inode);
Alexey Dobriyan881adb82008-07-25 01:48:29 -0700359 struct pde_opener *pdeo;
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700360 spin_lock(&pde->pde_unload_lock);
Al Viroca469f32013-04-03 19:57:00 -0400361 list_for_each_entry(pdeo, &pde->pde_openers, lh) {
362 if (pdeo->file == file) {
363 close_pdeo(pde, pdeo);
364 break;
365 }
Alexey Dobriyan881adb82008-07-25 01:48:29 -0700366 }
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700367 spin_unlock(&pde->pde_unload_lock);
Al Viroca469f32013-04-03 19:57:00 -0400368 return 0;
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700369}
370
371static const struct file_operations proc_reg_file_ops = {
372 .llseek = proc_reg_llseek,
373 .read = proc_reg_read,
374 .write = proc_reg_write,
375 .poll = proc_reg_poll,
376 .unlocked_ioctl = proc_reg_unlocked_ioctl,
377#ifdef CONFIG_COMPAT
378 .compat_ioctl = proc_reg_compat_ioctl,
379#endif
380 .mmap = proc_reg_mmap,
Alexey Dobriyanc4fe2442013-08-20 22:17:24 +0300381 .get_unmapped_area = proc_reg_get_unmapped_area,
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700382 .open = proc_reg_open,
383 .release = proc_reg_release,
384};
385
David Miller778f3dd2007-07-27 22:58:37 -0700386#ifdef CONFIG_COMPAT
387static const struct file_operations proc_reg_file_ops_no_compat = {
388 .llseek = proc_reg_llseek,
389 .read = proc_reg_read,
390 .write = proc_reg_write,
391 .poll = proc_reg_poll,
392 .unlocked_ioctl = proc_reg_unlocked_ioctl,
393 .mmap = proc_reg_mmap,
Alexey Dobriyanc4fe2442013-08-20 22:17:24 +0300394 .get_unmapped_area = proc_reg_get_unmapped_area,
David Miller778f3dd2007-07-27 22:58:37 -0700395 .open = proc_reg_open,
396 .release = proc_reg_release,
397};
398#endif
399
Alexey Dobriyan6d1b6e42011-01-12 17:00:33 -0800400struct inode *proc_get_inode(struct super_block *sb, struct proc_dir_entry *de)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401{
Linus Torvalds51f08852013-03-22 11:44:04 -0700402 struct inode *inode = new_inode_pseudo(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403
Linus Torvalds51f08852013-03-22 11:44:04 -0700404 if (inode) {
405 inode->i_ino = de->low_ino;
David Howellsa1d4aeb2008-02-07 00:15:45 -0800406 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
David Howellsa1d4aeb2008-02-07 00:15:45 -0800407 PROC_I(inode)->pde = de;
Alexey Dobriyan5e971dc2008-04-29 01:01:41 -0700408
409 if (de->mode) {
410 inode->i_mode = de->mode;
411 inode->i_uid = de->uid;
412 inode->i_gid = de->gid;
413 }
414 if (de->size)
415 inode->i_size = de->size;
416 if (de->nlink)
Miklos Szeredibfe86842011-10-28 14:13:29 +0200417 set_nlink(inode, de->nlink);
Al Virob6cdc732013-03-30 21:20:14 -0400418 WARN_ON(!de->proc_iops);
419 inode->i_op = de->proc_iops;
Alexey Dobriyan5e971dc2008-04-29 01:01:41 -0700420 if (de->proc_fops) {
421 if (S_ISREG(inode->i_mode)) {
David Howellsa1d4aeb2008-02-07 00:15:45 -0800422#ifdef CONFIG_COMPAT
Alexey Dobriyan5e971dc2008-04-29 01:01:41 -0700423 if (!de->proc_fops->compat_ioctl)
424 inode->i_fop =
425 &proc_reg_file_ops_no_compat;
426 else
David Howellsa1d4aeb2008-02-07 00:15:45 -0800427#endif
Alexey Dobriyan5e971dc2008-04-29 01:01:41 -0700428 inode->i_fop = &proc_reg_file_ops;
429 } else {
430 inode->i_fop = de->proc_fops;
David Howellsa1d4aeb2008-02-07 00:15:45 -0800431 }
Alexey Dobriyan786d7e12007-07-15 23:39:00 -0700432 }
Alexey Dobriyan99b76232009-03-25 22:48:06 +0300433 } else
Alexey Dobriyan135d5652009-12-15 16:45:39 -0800434 pde_put(de);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435 return inode;
Al Virod3d009c2013-01-25 20:11:22 -0500436}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437
Pavel Emelyanov07543f52007-10-18 23:40:08 -0700438int proc_fill_super(struct super_block *s)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439{
Maxim Patlasov87e0aab2013-02-20 13:13:32 +1100440 struct inode *root_inode;
441
Linus Torvalds92d03282006-07-15 12:20:05 -0700442 s->s_flags |= MS_NODIRATIME | MS_NOSUID | MS_NOEXEC;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443 s->s_blocksize = 1024;
444 s->s_blocksize_bits = 10;
445 s->s_magic = PROC_SUPER_MAGIC;
446 s->s_op = &proc_sops;
447 s->s_time_gran = 1;
448
Alexey Dobriyan135d5652009-12-15 16:45:39 -0800449 pde_get(&proc_root);
Maxim Patlasov87e0aab2013-02-20 13:13:32 +1100450 root_inode = proc_get_inode(s, &proc_root);
451 if (!root_inode) {
Andrew Morton87ebdc02013-02-27 17:03:16 -0800452 pr_err("proc_fill_super: get root inode failed\n");
Maxim Patlasov87e0aab2013-02-20 13:13:32 +1100453 return -ENOMEM;
454 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455
Maxim Patlasov87e0aab2013-02-20 13:13:32 +1100456 s->s_root = d_make_root(root_inode);
457 if (!s->s_root) {
Andrew Morton87ebdc02013-02-27 17:03:16 -0800458 pr_err("proc_fill_super: allocate dentry failed\n");
Maxim Patlasov87e0aab2013-02-20 13:13:32 +1100459 return -ENOMEM;
460 }
461
Al Viro021ada72013-03-29 19:27:05 -0400462 return proc_setup_self(s);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463}