1272eb014SEric Paris /* 2272eb014SEric Paris * fs/inotify_user.c - inotify support for userspace 3272eb014SEric Paris * 4272eb014SEric Paris * Authors: 5272eb014SEric Paris * John McCutchan <ttb@tentacle.dhs.org> 6272eb014SEric Paris * Robert Love <rml@novell.com> 7272eb014SEric Paris * 8272eb014SEric Paris * Copyright (C) 2005 John McCutchan 9272eb014SEric Paris * Copyright 2006 Hewlett-Packard Development Company, L.P. 10272eb014SEric Paris * 1163c882a0SEric Paris * Copyright (C) 2009 Eric Paris <Red Hat Inc> 1263c882a0SEric Paris * inotify was largely rewriten to make use of the fsnotify infrastructure 1363c882a0SEric Paris * 14272eb014SEric Paris * This program is free software; you can redistribute it and/or modify it 15272eb014SEric Paris * under the terms of the GNU General Public License as published by the 16272eb014SEric Paris * Free Software Foundation; either version 2, or (at your option) any 17272eb014SEric Paris * later version. 18272eb014SEric Paris * 19272eb014SEric Paris * This program is distributed in the hope that it will be useful, but 20272eb014SEric Paris * WITHOUT ANY WARRANTY; without even the implied warranty of 21272eb014SEric Paris * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 22272eb014SEric Paris * General Public License for more details. 23272eb014SEric Paris */ 24272eb014SEric Paris 25272eb014SEric Paris #include <linux/file.h> 2663c882a0SEric Paris #include <linux/fs.h> /* struct inode */ 2763c882a0SEric Paris #include <linux/fsnotify_backend.h> 2863c882a0SEric Paris #include <linux/idr.h> 2963c882a0SEric Paris #include <linux/init.h> /* module_init */ 30272eb014SEric Paris #include <linux/inotify.h> 3163c882a0SEric Paris #include <linux/kernel.h> /* roundup() */ 3263c882a0SEric Paris #include <linux/namei.h> /* LOOKUP_FOLLOW */ 3363c882a0SEric Paris #include <linux/sched.h> /* struct user */ 3463c882a0SEric Paris #include <linux/slab.h> /* struct kmem_cache */ 35272eb014SEric Paris #include <linux/syscalls.h> 3663c882a0SEric Paris #include <linux/types.h> 37c44dcc56SAl Viro #include <linux/anon_inodes.h> 3863c882a0SEric Paris #include <linux/uaccess.h> 3963c882a0SEric Paris #include <linux/poll.h> 4063c882a0SEric Paris #include <linux/wait.h> 4163c882a0SEric Paris 4263c882a0SEric Paris #include "inotify.h" 43272eb014SEric Paris 44272eb014SEric Paris #include <asm/ioctls.h> 45272eb014SEric Paris 46272eb014SEric Paris /* these are configurable via /proc/sys/fs/inotify/ */ 47272eb014SEric Paris static int inotify_max_user_instances __read_mostly; 48272eb014SEric Paris static int inotify_max_queued_events __read_mostly; 4963c882a0SEric Paris int inotify_max_user_watches __read_mostly; 5063c882a0SEric Paris 5163c882a0SEric Paris static struct kmem_cache *inotify_inode_mark_cachep __read_mostly; 5263c882a0SEric Paris struct kmem_cache *event_priv_cachep __read_mostly; 53272eb014SEric Paris 54272eb014SEric Paris /* 5563c882a0SEric Paris * When inotify registers a new group it increments this and uses that 5663c882a0SEric Paris * value as an offset to set the fsnotify group "name" and priority. 57272eb014SEric Paris */ 5863c882a0SEric Paris static atomic_t inotify_grp_num; 59272eb014SEric Paris 60272eb014SEric Paris #ifdef CONFIG_SYSCTL 61272eb014SEric Paris 62272eb014SEric Paris #include <linux/sysctl.h> 63272eb014SEric Paris 64272eb014SEric Paris static int zero; 65272eb014SEric Paris 66272eb014SEric Paris ctl_table inotify_table[] = { 67272eb014SEric Paris { 68272eb014SEric Paris .procname = "max_user_instances", 69272eb014SEric Paris .data = &inotify_max_user_instances, 70272eb014SEric Paris .maxlen = sizeof(int), 71272eb014SEric Paris .mode = 0644, 726d456111SEric W. Biederman .proc_handler = proc_dointvec_minmax, 73272eb014SEric Paris .extra1 = &zero, 74272eb014SEric Paris }, 75272eb014SEric Paris { 76272eb014SEric Paris .procname = "max_user_watches", 77272eb014SEric Paris .data = &inotify_max_user_watches, 78272eb014SEric Paris .maxlen = sizeof(int), 79272eb014SEric Paris .mode = 0644, 806d456111SEric W. Biederman .proc_handler = proc_dointvec_minmax, 81272eb014SEric Paris .extra1 = &zero, 82272eb014SEric Paris }, 83272eb014SEric Paris { 84272eb014SEric Paris .procname = "max_queued_events", 85272eb014SEric Paris .data = &inotify_max_queued_events, 86272eb014SEric Paris .maxlen = sizeof(int), 87272eb014SEric Paris .mode = 0644, 886d456111SEric W. Biederman .proc_handler = proc_dointvec_minmax, 89272eb014SEric Paris .extra1 = &zero 90272eb014SEric Paris }, 91ab09203eSEric W. Biederman { } 92272eb014SEric Paris }; 93272eb014SEric Paris #endif /* CONFIG_SYSCTL */ 94272eb014SEric Paris 9563c882a0SEric Paris static inline __u32 inotify_arg_to_mask(u32 arg) 96272eb014SEric Paris { 9763c882a0SEric Paris __u32 mask; 9863c882a0SEric Paris 9963c882a0SEric Paris /* everything should accept their own ignored and cares about children */ 10063c882a0SEric Paris mask = (FS_IN_IGNORED | FS_EVENT_ON_CHILD); 10163c882a0SEric Paris 10263c882a0SEric Paris /* mask off the flags used to open the fd */ 10363c882a0SEric Paris mask |= (arg & (IN_ALL_EVENTS | IN_ONESHOT)); 10463c882a0SEric Paris 10563c882a0SEric Paris return mask; 106272eb014SEric Paris } 107272eb014SEric Paris 10863c882a0SEric Paris static inline u32 inotify_mask_to_arg(__u32 mask) 109272eb014SEric Paris { 11063c882a0SEric Paris return mask & (IN_ALL_EVENTS | IN_ISDIR | IN_UNMOUNT | IN_IGNORED | 11163c882a0SEric Paris IN_Q_OVERFLOW); 112272eb014SEric Paris } 113272eb014SEric Paris 11463c882a0SEric Paris /* intofiy userspace file descriptor functions */ 115272eb014SEric Paris static unsigned int inotify_poll(struct file *file, poll_table *wait) 116272eb014SEric Paris { 11763c882a0SEric Paris struct fsnotify_group *group = file->private_data; 118272eb014SEric Paris int ret = 0; 119272eb014SEric Paris 12063c882a0SEric Paris poll_wait(file, &group->notification_waitq, wait); 12163c882a0SEric Paris mutex_lock(&group->notification_mutex); 12263c882a0SEric Paris if (!fsnotify_notify_queue_is_empty(group)) 123272eb014SEric Paris ret = POLLIN | POLLRDNORM; 12463c882a0SEric Paris mutex_unlock(&group->notification_mutex); 125272eb014SEric Paris 126272eb014SEric Paris return ret; 127272eb014SEric Paris } 128272eb014SEric Paris 1293632dee2SVegard Nossum /* 1303632dee2SVegard Nossum * Get an inotify_kernel_event if one exists and is small 1313632dee2SVegard Nossum * enough to fit in "count". Return an error pointer if 1323632dee2SVegard Nossum * not large enough. 1333632dee2SVegard Nossum * 13463c882a0SEric Paris * Called with the group->notification_mutex held. 1353632dee2SVegard Nossum */ 13663c882a0SEric Paris static struct fsnotify_event *get_one_event(struct fsnotify_group *group, 1373632dee2SVegard Nossum size_t count) 1383632dee2SVegard Nossum { 1393632dee2SVegard Nossum size_t event_size = sizeof(struct inotify_event); 14063c882a0SEric Paris struct fsnotify_event *event; 1413632dee2SVegard Nossum 14263c882a0SEric Paris if (fsnotify_notify_queue_is_empty(group)) 1433632dee2SVegard Nossum return NULL; 1443632dee2SVegard Nossum 14563c882a0SEric Paris event = fsnotify_peek_notify_event(group); 14663c882a0SEric Paris 14783cb10f0SEric Paris if (event->name_len) 14883cb10f0SEric Paris event_size += roundup(event->name_len + 1, event_size); 1493632dee2SVegard Nossum 1503632dee2SVegard Nossum if (event_size > count) 1513632dee2SVegard Nossum return ERR_PTR(-EINVAL); 1523632dee2SVegard Nossum 15363c882a0SEric Paris /* held the notification_mutex the whole time, so this is the 15463c882a0SEric Paris * same event we peeked above */ 15563c882a0SEric Paris fsnotify_remove_notify_event(group); 15663c882a0SEric Paris 15763c882a0SEric Paris return event; 1583632dee2SVegard Nossum } 1593632dee2SVegard Nossum 1603632dee2SVegard Nossum /* 1613632dee2SVegard Nossum * Copy an event to user space, returning how much we copied. 1623632dee2SVegard Nossum * 1633632dee2SVegard Nossum * We already checked that the event size is smaller than the 1643632dee2SVegard Nossum * buffer we had in "get_one_event()" above. 1653632dee2SVegard Nossum */ 16663c882a0SEric Paris static ssize_t copy_event_to_user(struct fsnotify_group *group, 16763c882a0SEric Paris struct fsnotify_event *event, 1683632dee2SVegard Nossum char __user *buf) 1693632dee2SVegard Nossum { 17063c882a0SEric Paris struct inotify_event inotify_event; 17163c882a0SEric Paris struct fsnotify_event_private_data *fsn_priv; 17263c882a0SEric Paris struct inotify_event_private_data *priv; 1733632dee2SVegard Nossum size_t event_size = sizeof(struct inotify_event); 174b962e731SBrian Rogers size_t name_len = 0; 1753632dee2SVegard Nossum 17663c882a0SEric Paris /* we get the inotify watch descriptor from the event private data */ 17763c882a0SEric Paris spin_lock(&event->lock); 17863c882a0SEric Paris fsn_priv = fsnotify_remove_priv_from_event(group, event); 17963c882a0SEric Paris spin_unlock(&event->lock); 18063c882a0SEric Paris 18163c882a0SEric Paris if (!fsn_priv) 18263c882a0SEric Paris inotify_event.wd = -1; 18363c882a0SEric Paris else { 18463c882a0SEric Paris priv = container_of(fsn_priv, struct inotify_event_private_data, 18563c882a0SEric Paris fsnotify_event_priv_data); 18663c882a0SEric Paris inotify_event.wd = priv->wd; 18763c882a0SEric Paris inotify_free_event_priv(fsn_priv); 18863c882a0SEric Paris } 18963c882a0SEric Paris 190b962e731SBrian Rogers /* 191b962e731SBrian Rogers * round up event->name_len so it is a multiple of event_size 1920db501bdSEric W. Biederman * plus an extra byte for the terminating '\0'. 1930db501bdSEric W. Biederman */ 194b962e731SBrian Rogers if (event->name_len) 1950db501bdSEric W. Biederman name_len = roundup(event->name_len + 1, event_size); 19663c882a0SEric Paris inotify_event.len = name_len; 19763c882a0SEric Paris 19863c882a0SEric Paris inotify_event.mask = inotify_mask_to_arg(event->mask); 19963c882a0SEric Paris inotify_event.cookie = event->sync_cookie; 20063c882a0SEric Paris 20163c882a0SEric Paris /* send the main event */ 20263c882a0SEric Paris if (copy_to_user(buf, &inotify_event, event_size)) 2033632dee2SVegard Nossum return -EFAULT; 2043632dee2SVegard Nossum 2053632dee2SVegard Nossum buf += event_size; 2063632dee2SVegard Nossum 20763c882a0SEric Paris /* 20863c882a0SEric Paris * fsnotify only stores the pathname, so here we have to send the pathname 20963c882a0SEric Paris * and then pad that pathname out to a multiple of sizeof(inotify_event) 21063c882a0SEric Paris * with zeros. I get my zeros from the nul_inotify_event. 21163c882a0SEric Paris */ 21263c882a0SEric Paris if (name_len) { 21363c882a0SEric Paris unsigned int len_to_zero = name_len - event->name_len; 21463c882a0SEric Paris /* copy the path name */ 21563c882a0SEric Paris if (copy_to_user(buf, event->file_name, event->name_len)) 2163632dee2SVegard Nossum return -EFAULT; 21763c882a0SEric Paris buf += event->name_len; 2183632dee2SVegard Nossum 2190db501bdSEric W. Biederman /* fill userspace with 0's */ 2200db501bdSEric W. Biederman if (clear_user(buf, len_to_zero)) 22163c882a0SEric Paris return -EFAULT; 22263c882a0SEric Paris buf += len_to_zero; 22363c882a0SEric Paris event_size += name_len; 2243632dee2SVegard Nossum } 22563c882a0SEric Paris 2263632dee2SVegard Nossum return event_size; 2273632dee2SVegard Nossum } 2283632dee2SVegard Nossum 229272eb014SEric Paris static ssize_t inotify_read(struct file *file, char __user *buf, 230272eb014SEric Paris size_t count, loff_t *pos) 231272eb014SEric Paris { 23263c882a0SEric Paris struct fsnotify_group *group; 23363c882a0SEric Paris struct fsnotify_event *kevent; 234272eb014SEric Paris char __user *start; 235272eb014SEric Paris int ret; 236272eb014SEric Paris DEFINE_WAIT(wait); 237272eb014SEric Paris 238272eb014SEric Paris start = buf; 23963c882a0SEric Paris group = file->private_data; 240272eb014SEric Paris 241272eb014SEric Paris while (1) { 24263c882a0SEric Paris prepare_to_wait(&group->notification_waitq, &wait, TASK_INTERRUPTIBLE); 243272eb014SEric Paris 24463c882a0SEric Paris mutex_lock(&group->notification_mutex); 24563c882a0SEric Paris kevent = get_one_event(group, count); 24663c882a0SEric Paris mutex_unlock(&group->notification_mutex); 247272eb014SEric Paris 2483632dee2SVegard Nossum if (kevent) { 2493632dee2SVegard Nossum ret = PTR_ERR(kevent); 2503632dee2SVegard Nossum if (IS_ERR(kevent)) 251272eb014SEric Paris break; 25263c882a0SEric Paris ret = copy_event_to_user(group, kevent, buf); 25363c882a0SEric Paris fsnotify_put_event(kevent); 2543632dee2SVegard Nossum if (ret < 0) 2553632dee2SVegard Nossum break; 2563632dee2SVegard Nossum buf += ret; 2573632dee2SVegard Nossum count -= ret; 2583632dee2SVegard Nossum continue; 259272eb014SEric Paris } 260272eb014SEric Paris 2613632dee2SVegard Nossum ret = -EAGAIN; 2623632dee2SVegard Nossum if (file->f_flags & O_NONBLOCK) 263272eb014SEric Paris break; 2643632dee2SVegard Nossum ret = -EINTR; 2653632dee2SVegard Nossum if (signal_pending(current)) 2663632dee2SVegard Nossum break; 2673632dee2SVegard Nossum 2683632dee2SVegard Nossum if (start != buf) 2693632dee2SVegard Nossum break; 270272eb014SEric Paris 271272eb014SEric Paris schedule(); 272272eb014SEric Paris } 273272eb014SEric Paris 27463c882a0SEric Paris finish_wait(&group->notification_waitq, &wait); 2753632dee2SVegard Nossum if (start != buf && ret != -EFAULT) 276272eb014SEric Paris ret = buf - start; 277272eb014SEric Paris return ret; 278272eb014SEric Paris } 279272eb014SEric Paris 280272eb014SEric Paris static int inotify_fasync(int fd, struct file *file, int on) 281272eb014SEric Paris { 28263c882a0SEric Paris struct fsnotify_group *group = file->private_data; 283272eb014SEric Paris 28463c882a0SEric Paris return fasync_helper(fd, file, on, &group->inotify_data.fa) >= 0 ? 0 : -EIO; 285272eb014SEric Paris } 286272eb014SEric Paris 287272eb014SEric Paris static int inotify_release(struct inode *ignored, struct file *file) 288272eb014SEric Paris { 28963c882a0SEric Paris struct fsnotify_group *group = file->private_data; 290bdae997fSKeith Packard struct user_struct *user = group->inotify_data.user; 291272eb014SEric Paris 29263c882a0SEric Paris fsnotify_clear_marks_by_group(group); 293272eb014SEric Paris 29463c882a0SEric Paris /* free this group, matching get was inotify_init->fsnotify_obtain_group */ 29563c882a0SEric Paris fsnotify_put_group(group); 296272eb014SEric Paris 297bdae997fSKeith Packard atomic_dec(&user->inotify_devs); 298bdae997fSKeith Packard 299272eb014SEric Paris return 0; 300272eb014SEric Paris } 301272eb014SEric Paris 302272eb014SEric Paris static long inotify_ioctl(struct file *file, unsigned int cmd, 303272eb014SEric Paris unsigned long arg) 304272eb014SEric Paris { 30563c882a0SEric Paris struct fsnotify_group *group; 30663c882a0SEric Paris struct fsnotify_event_holder *holder; 30763c882a0SEric Paris struct fsnotify_event *event; 308272eb014SEric Paris void __user *p; 309272eb014SEric Paris int ret = -ENOTTY; 31063c882a0SEric Paris size_t send_len = 0; 311272eb014SEric Paris 31263c882a0SEric Paris group = file->private_data; 313272eb014SEric Paris p = (void __user *) arg; 314272eb014SEric Paris 315272eb014SEric Paris switch (cmd) { 316272eb014SEric Paris case FIONREAD: 31763c882a0SEric Paris mutex_lock(&group->notification_mutex); 31863c882a0SEric Paris list_for_each_entry(holder, &group->notification_list, event_list) { 31963c882a0SEric Paris event = holder->event; 32063c882a0SEric Paris send_len += sizeof(struct inotify_event); 32183cb10f0SEric Paris if (event->name_len) 32283cb10f0SEric Paris send_len += roundup(event->name_len + 1, 32363c882a0SEric Paris sizeof(struct inotify_event)); 32463c882a0SEric Paris } 32563c882a0SEric Paris mutex_unlock(&group->notification_mutex); 32663c882a0SEric Paris ret = put_user(send_len, (int __user *) p); 327272eb014SEric Paris break; 328272eb014SEric Paris } 329272eb014SEric Paris 330272eb014SEric Paris return ret; 331272eb014SEric Paris } 332272eb014SEric Paris 333272eb014SEric Paris static const struct file_operations inotify_fops = { 334272eb014SEric Paris .poll = inotify_poll, 335272eb014SEric Paris .read = inotify_read, 336272eb014SEric Paris .fasync = inotify_fasync, 337272eb014SEric Paris .release = inotify_release, 338272eb014SEric Paris .unlocked_ioctl = inotify_ioctl, 339272eb014SEric Paris .compat_ioctl = inotify_ioctl, 340272eb014SEric Paris }; 341272eb014SEric Paris 342272eb014SEric Paris 34363c882a0SEric Paris /* 34463c882a0SEric Paris * find_inode - resolve a user-given path to a specific inode 34563c882a0SEric Paris */ 34663c882a0SEric Paris static int inotify_find_inode(const char __user *dirname, struct path *path, unsigned flags) 34763c882a0SEric Paris { 34863c882a0SEric Paris int error; 34963c882a0SEric Paris 35063c882a0SEric Paris error = user_path_at(AT_FDCWD, dirname, flags, path); 35163c882a0SEric Paris if (error) 35263c882a0SEric Paris return error; 35363c882a0SEric Paris /* you can only watch an inode if you have read permissions on it */ 35463c882a0SEric Paris error = inode_permission(path->dentry->d_inode, MAY_READ); 35563c882a0SEric Paris if (error) 35663c882a0SEric Paris path_put(path); 35763c882a0SEric Paris return error; 35863c882a0SEric Paris } 35963c882a0SEric Paris 360b7ba8371SEric Paris static int inotify_add_to_idr(struct idr *idr, spinlock_t *idr_lock, 361b7ba8371SEric Paris int last_wd, 362b7ba8371SEric Paris struct inotify_inode_mark_entry *ientry) 363b7ba8371SEric Paris { 364b7ba8371SEric Paris int ret; 365b7ba8371SEric Paris 366b7ba8371SEric Paris do { 367b7ba8371SEric Paris if (unlikely(!idr_pre_get(idr, GFP_KERNEL))) 368b7ba8371SEric Paris return -ENOMEM; 369b7ba8371SEric Paris 370b7ba8371SEric Paris spin_lock(idr_lock); 371b7ba8371SEric Paris ret = idr_get_new_above(idr, ientry, last_wd + 1, 372b7ba8371SEric Paris &ientry->wd); 373b7ba8371SEric Paris /* we added the mark to the idr, take a reference */ 374b7ba8371SEric Paris if (!ret) 375b7ba8371SEric Paris fsnotify_get_mark(&ientry->fsn_entry); 376b7ba8371SEric Paris spin_unlock(idr_lock); 377b7ba8371SEric Paris } while (ret == -EAGAIN); 378b7ba8371SEric Paris 379b7ba8371SEric Paris return ret; 380b7ba8371SEric Paris } 381b7ba8371SEric Paris 382b7ba8371SEric Paris static struct inotify_inode_mark_entry *inotify_idr_find_locked(struct fsnotify_group *group, 383b7ba8371SEric Paris int wd) 384b7ba8371SEric Paris { 385b7ba8371SEric Paris struct idr *idr = &group->inotify_data.idr; 386b7ba8371SEric Paris spinlock_t *idr_lock = &group->inotify_data.idr_lock; 387b7ba8371SEric Paris struct inotify_inode_mark_entry *ientry; 388b7ba8371SEric Paris 389b7ba8371SEric Paris assert_spin_locked(idr_lock); 390b7ba8371SEric Paris 391b7ba8371SEric Paris ientry = idr_find(idr, wd); 392b7ba8371SEric Paris if (ientry) { 393b7ba8371SEric Paris struct fsnotify_mark_entry *fsn_entry = &ientry->fsn_entry; 394b7ba8371SEric Paris 395b7ba8371SEric Paris fsnotify_get_mark(fsn_entry); 396b7ba8371SEric Paris /* One ref for being in the idr, one ref we just took */ 397b7ba8371SEric Paris BUG_ON(atomic_read(&fsn_entry->refcnt) < 2); 398b7ba8371SEric Paris } 399b7ba8371SEric Paris 400b7ba8371SEric Paris return ientry; 401b7ba8371SEric Paris } 402b7ba8371SEric Paris 403b7ba8371SEric Paris static struct inotify_inode_mark_entry *inotify_idr_find(struct fsnotify_group *group, 404b7ba8371SEric Paris int wd) 405b7ba8371SEric Paris { 406b7ba8371SEric Paris struct inotify_inode_mark_entry *ientry; 407b7ba8371SEric Paris spinlock_t *idr_lock = &group->inotify_data.idr_lock; 408b7ba8371SEric Paris 409b7ba8371SEric Paris spin_lock(idr_lock); 410b7ba8371SEric Paris ientry = inotify_idr_find_locked(group, wd); 411b7ba8371SEric Paris spin_unlock(idr_lock); 412b7ba8371SEric Paris 413b7ba8371SEric Paris return ientry; 414b7ba8371SEric Paris } 415b7ba8371SEric Paris 416b7ba8371SEric Paris static void do_inotify_remove_from_idr(struct fsnotify_group *group, 417b7ba8371SEric Paris struct inotify_inode_mark_entry *ientry) 418b7ba8371SEric Paris { 419b7ba8371SEric Paris struct idr *idr = &group->inotify_data.idr; 420b7ba8371SEric Paris spinlock_t *idr_lock = &group->inotify_data.idr_lock; 421b7ba8371SEric Paris int wd = ientry->wd; 422b7ba8371SEric Paris 423b7ba8371SEric Paris assert_spin_locked(idr_lock); 424b7ba8371SEric Paris 425b7ba8371SEric Paris idr_remove(idr, wd); 426b7ba8371SEric Paris 427b7ba8371SEric Paris /* removed from the idr, drop that ref */ 428b7ba8371SEric Paris fsnotify_put_mark(&ientry->fsn_entry); 429b7ba8371SEric Paris } 430b7ba8371SEric Paris 431dead537dSEric Paris /* 432dead537dSEric Paris * Remove the mark from the idr (if present) and drop the reference 433dead537dSEric Paris * on the mark because it was in the idr. 434dead537dSEric Paris */ 4357e790dd5SEric Paris static void inotify_remove_from_idr(struct fsnotify_group *group, 4367e790dd5SEric Paris struct inotify_inode_mark_entry *ientry) 4377e790dd5SEric Paris { 438b7ba8371SEric Paris spinlock_t *idr_lock = &group->inotify_data.idr_lock; 439b7ba8371SEric Paris struct inotify_inode_mark_entry *found_ientry = NULL; 440dead537dSEric Paris int wd; 4417e790dd5SEric Paris 442b7ba8371SEric Paris spin_lock(idr_lock); 443dead537dSEric Paris wd = ientry->wd; 444dead537dSEric Paris 445b7ba8371SEric Paris /* 446b7ba8371SEric Paris * does this ientry think it is in the idr? we shouldn't get called 447b7ba8371SEric Paris * if it wasn't.... 448b7ba8371SEric Paris */ 449b7ba8371SEric Paris if (wd == -1) { 450b7ba8371SEric Paris printk(KERN_WARNING "%s: ientry=%p ientry->wd=%d ientry->group=%p" 451b7ba8371SEric Paris " ientry->inode=%p\n", __func__, ientry, ientry->wd, 452b7ba8371SEric Paris ientry->fsn_entry.group, ientry->fsn_entry.inode); 453dead537dSEric Paris WARN_ON(1); 454dead537dSEric Paris goto out; 4557e790dd5SEric Paris } 456dead537dSEric Paris 457b7ba8371SEric Paris /* Lets look in the idr to see if we find it */ 458b7ba8371SEric Paris found_ientry = inotify_idr_find_locked(group, wd); 459b7ba8371SEric Paris if (unlikely(!found_ientry)) { 460b7ba8371SEric Paris printk(KERN_WARNING "%s: ientry=%p ientry->wd=%d ientry->group=%p" 461b7ba8371SEric Paris " ientry->inode=%p\n", __func__, ientry, ientry->wd, 462b7ba8371SEric Paris ientry->fsn_entry.group, ientry->fsn_entry.inode); 463b7ba8371SEric Paris WARN_ON(1); 464b7ba8371SEric Paris goto out; 465b7ba8371SEric Paris } 466dead537dSEric Paris 467b7ba8371SEric Paris /* 468b7ba8371SEric Paris * We found an entry in the idr at the right wd, but it's 469b7ba8371SEric Paris * not the entry we were told to remove. eparis seriously 470b7ba8371SEric Paris * fucked up somewhere. 471b7ba8371SEric Paris */ 472b7ba8371SEric Paris if (unlikely(found_ientry != ientry)) { 473b7ba8371SEric Paris WARN_ON(1); 474b7ba8371SEric Paris printk(KERN_WARNING "%s: ientry=%p ientry->wd=%d ientry->group=%p " 475b7ba8371SEric Paris "entry->inode=%p found_ientry=%p found_ientry->wd=%d " 476b7ba8371SEric Paris "found_ientry->group=%p found_ientry->inode=%p\n", 477b7ba8371SEric Paris __func__, ientry, ientry->wd, ientry->fsn_entry.group, 478b7ba8371SEric Paris ientry->fsn_entry.inode, found_ientry, found_ientry->wd, 479b7ba8371SEric Paris found_ientry->fsn_entry.group, 480b7ba8371SEric Paris found_ientry->fsn_entry.inode); 481b7ba8371SEric Paris goto out; 482b7ba8371SEric Paris } 483dead537dSEric Paris 484b7ba8371SEric Paris /* 485b7ba8371SEric Paris * One ref for being in the idr 486b7ba8371SEric Paris * one ref held by the caller trying to kill us 487b7ba8371SEric Paris * one ref grabbed by inotify_idr_find 488b7ba8371SEric Paris */ 489b7ba8371SEric Paris if (unlikely(atomic_read(&ientry->fsn_entry.refcnt) < 3)) { 490b7ba8371SEric Paris printk(KERN_WARNING "%s: ientry=%p ientry->wd=%d ientry->group=%p" 491b7ba8371SEric Paris " ientry->inode=%p\n", __func__, ientry, ientry->wd, 492b7ba8371SEric Paris ientry->fsn_entry.group, ientry->fsn_entry.inode); 493b7ba8371SEric Paris /* we can't really recover with bad ref cnting.. */ 494b7ba8371SEric Paris BUG(); 495b7ba8371SEric Paris } 496b7ba8371SEric Paris 497b7ba8371SEric Paris do_inotify_remove_from_idr(group, ientry); 498dead537dSEric Paris out: 499b7ba8371SEric Paris /* match the ref taken by inotify_idr_find_locked() */ 500b7ba8371SEric Paris if (found_ientry) 501b7ba8371SEric Paris fsnotify_put_mark(&found_ientry->fsn_entry); 502b7ba8371SEric Paris ientry->wd = -1; 503b7ba8371SEric Paris spin_unlock(idr_lock); 504dead537dSEric Paris } 505dead537dSEric Paris 50663c882a0SEric Paris /* 507dead537dSEric Paris * Send IN_IGNORED for this wd, remove this wd from the idr. 50863c882a0SEric Paris */ 509528da3e9SEric Paris void inotify_ignored_and_remove_idr(struct fsnotify_mark_entry *entry, 510528da3e9SEric Paris struct fsnotify_group *group) 51163c882a0SEric Paris { 51263c882a0SEric Paris struct inotify_inode_mark_entry *ientry; 513f44aebccSEric Paris struct fsnotify_event *ignored_event; 51463c882a0SEric Paris struct inotify_event_private_data *event_priv; 51563c882a0SEric Paris struct fsnotify_event_private_data *fsn_event_priv; 516eef3a116SEric Paris int ret; 51763c882a0SEric Paris 518f44aebccSEric Paris ignored_event = fsnotify_create_event(NULL, FS_IN_IGNORED, NULL, 519f44aebccSEric Paris FSNOTIFY_EVENT_NONE, NULL, 0, 520f44aebccSEric Paris GFP_NOFS); 521f44aebccSEric Paris if (!ignored_event) 522f44aebccSEric Paris return; 523f44aebccSEric Paris 52463c882a0SEric Paris ientry = container_of(entry, struct inotify_inode_mark_entry, fsn_entry); 52563c882a0SEric Paris 526f44aebccSEric Paris event_priv = kmem_cache_alloc(event_priv_cachep, GFP_NOFS); 52763c882a0SEric Paris if (unlikely(!event_priv)) 52863c882a0SEric Paris goto skip_send_ignore; 52963c882a0SEric Paris 53063c882a0SEric Paris fsn_event_priv = &event_priv->fsnotify_event_priv_data; 53163c882a0SEric Paris 53263c882a0SEric Paris fsn_event_priv->group = group; 53363c882a0SEric Paris event_priv->wd = ientry->wd; 53463c882a0SEric Paris 535eef3a116SEric Paris ret = fsnotify_add_notify_event(group, ignored_event, fsn_event_priv); 536eef3a116SEric Paris if (ret) 53763c882a0SEric Paris inotify_free_event_priv(fsn_event_priv); 53863c882a0SEric Paris 53963c882a0SEric Paris skip_send_ignore: 54063c882a0SEric Paris 541f44aebccSEric Paris /* matches the reference taken when the event was created */ 542f44aebccSEric Paris fsnotify_put_event(ignored_event); 543f44aebccSEric Paris 54463c882a0SEric Paris /* remove this entry from the idr */ 5457e790dd5SEric Paris inotify_remove_from_idr(group, ientry); 54663c882a0SEric Paris 5475549f7cdSEric Paris atomic_dec(&group->inotify_data.user->inotify_watches); 54863c882a0SEric Paris } 54963c882a0SEric Paris 55063c882a0SEric Paris /* ding dong the mark is dead */ 55163c882a0SEric Paris static void inotify_free_mark(struct fsnotify_mark_entry *entry) 55263c882a0SEric Paris { 553*31ddd326SEric Paris struct inotify_inode_mark_entry *ientry; 554*31ddd326SEric Paris 555*31ddd326SEric Paris ientry = container_of(entry, struct inotify_inode_mark_entry, fsn_entry); 55663c882a0SEric Paris 55763c882a0SEric Paris kmem_cache_free(inotify_inode_mark_cachep, ientry); 55863c882a0SEric Paris } 55963c882a0SEric Paris 56052cef755SEric Paris static int inotify_update_existing_watch(struct fsnotify_group *group, 56152cef755SEric Paris struct inode *inode, 56252cef755SEric Paris u32 arg) 56363c882a0SEric Paris { 56452cef755SEric Paris struct fsnotify_mark_entry *entry; 56563c882a0SEric Paris struct inotify_inode_mark_entry *ientry; 56663c882a0SEric Paris __u32 old_mask, new_mask; 56752cef755SEric Paris __u32 mask; 56852cef755SEric Paris int add = (arg & IN_MASK_ADD); 56952cef755SEric Paris int ret; 57063c882a0SEric Paris 57163c882a0SEric Paris /* don't allow invalid bits: we don't want flags set */ 57263c882a0SEric Paris mask = inotify_arg_to_mask(arg); 57363c882a0SEric Paris if (unlikely(!mask)) 57463c882a0SEric Paris return -EINVAL; 57563c882a0SEric Paris 57663c882a0SEric Paris spin_lock(&inode->i_lock); 57763c882a0SEric Paris entry = fsnotify_find_mark_entry(group, inode); 57863c882a0SEric Paris spin_unlock(&inode->i_lock); 57952cef755SEric Paris if (!entry) 58052cef755SEric Paris return -ENOENT; 58152cef755SEric Paris 58263c882a0SEric Paris ientry = container_of(entry, struct inotify_inode_mark_entry, fsn_entry); 58375fe2b26SEric Paris 58463c882a0SEric Paris spin_lock(&entry->lock); 58563c882a0SEric Paris 58663c882a0SEric Paris old_mask = entry->mask; 58763c882a0SEric Paris if (add) { 58863c882a0SEric Paris entry->mask |= mask; 58963c882a0SEric Paris new_mask = entry->mask; 59063c882a0SEric Paris } else { 59163c882a0SEric Paris entry->mask = mask; 59263c882a0SEric Paris new_mask = entry->mask; 59363c882a0SEric Paris } 59463c882a0SEric Paris 59563c882a0SEric Paris spin_unlock(&entry->lock); 59663c882a0SEric Paris 59763c882a0SEric Paris if (old_mask != new_mask) { 59863c882a0SEric Paris /* more bits in old than in new? */ 59963c882a0SEric Paris int dropped = (old_mask & ~new_mask); 60063c882a0SEric Paris /* more bits in this entry than the inode's mask? */ 60163c882a0SEric Paris int do_inode = (new_mask & ~inode->i_fsnotify_mask); 60263c882a0SEric Paris /* more bits in this entry than the group? */ 60363c882a0SEric Paris int do_group = (new_mask & ~group->mask); 60463c882a0SEric Paris 60563c882a0SEric Paris /* update the inode with this new entry */ 60663c882a0SEric Paris if (dropped || do_inode) 60763c882a0SEric Paris fsnotify_recalc_inode_mask(inode); 60863c882a0SEric Paris 60963c882a0SEric Paris /* update the group mask with the new mask */ 61063c882a0SEric Paris if (dropped || do_group) 61163c882a0SEric Paris fsnotify_recalc_group_mask(group); 61263c882a0SEric Paris } 61363c882a0SEric Paris 61452cef755SEric Paris /* return the wd */ 61552cef755SEric Paris ret = ientry->wd; 61652cef755SEric Paris 61752cef755SEric Paris /* match the get from fsnotify_find_mark_entry() */ 61875fe2b26SEric Paris fsnotify_put_mark(entry); 61975fe2b26SEric Paris 62052cef755SEric Paris return ret; 62163c882a0SEric Paris } 6227e790dd5SEric Paris 62352cef755SEric Paris static int inotify_new_watch(struct fsnotify_group *group, 62452cef755SEric Paris struct inode *inode, 62552cef755SEric Paris u32 arg) 62652cef755SEric Paris { 62752cef755SEric Paris struct inotify_inode_mark_entry *tmp_ientry; 62852cef755SEric Paris __u32 mask; 62952cef755SEric Paris int ret; 630b7ba8371SEric Paris struct idr *idr = &group->inotify_data.idr; 631b7ba8371SEric Paris spinlock_t *idr_lock = &group->inotify_data.idr_lock; 63252cef755SEric Paris 63352cef755SEric Paris /* don't allow invalid bits: we don't want flags set */ 63452cef755SEric Paris mask = inotify_arg_to_mask(arg); 63552cef755SEric Paris if (unlikely(!mask)) 63652cef755SEric Paris return -EINVAL; 63752cef755SEric Paris 63852cef755SEric Paris tmp_ientry = kmem_cache_alloc(inotify_inode_mark_cachep, GFP_KERNEL); 63952cef755SEric Paris if (unlikely(!tmp_ientry)) 64052cef755SEric Paris return -ENOMEM; 64152cef755SEric Paris 64252cef755SEric Paris fsnotify_init_mark(&tmp_ientry->fsn_entry, inotify_free_mark); 64352cef755SEric Paris tmp_ientry->fsn_entry.mask = mask; 64452cef755SEric Paris tmp_ientry->wd = -1; 64552cef755SEric Paris 64652cef755SEric Paris ret = -ENOSPC; 64752cef755SEric Paris if (atomic_read(&group->inotify_data.user->inotify_watches) >= inotify_max_user_watches) 64852cef755SEric Paris goto out_err; 649b7ba8371SEric Paris 650b7ba8371SEric Paris ret = inotify_add_to_idr(idr, idr_lock, group->inotify_data.last_wd, 651b7ba8371SEric Paris tmp_ientry); 652b7ba8371SEric Paris if (ret) 65352cef755SEric Paris goto out_err; 65452cef755SEric Paris 65552cef755SEric Paris /* we are on the idr, now get on the inode */ 65640554c3dSEric Paris ret = fsnotify_add_mark(&tmp_ientry->fsn_entry, group, inode, 0); 65752cef755SEric Paris if (ret) { 65852cef755SEric Paris /* we failed to get on the inode, get off the idr */ 65952cef755SEric Paris inotify_remove_from_idr(group, tmp_ientry); 66052cef755SEric Paris goto out_err; 66152cef755SEric Paris } 66252cef755SEric Paris 66352cef755SEric Paris /* update the idr hint, who cares about races, it's just a hint */ 66452cef755SEric Paris group->inotify_data.last_wd = tmp_ientry->wd; 66552cef755SEric Paris 66652cef755SEric Paris /* increment the number of watches the user has */ 66752cef755SEric Paris atomic_inc(&group->inotify_data.user->inotify_watches); 66852cef755SEric Paris 66952cef755SEric Paris /* return the watch descriptor for this new entry */ 67052cef755SEric Paris ret = tmp_ientry->wd; 67152cef755SEric Paris 672750a8870SEric Paris /* if this mark added a new event update the group mask */ 673750a8870SEric Paris if (mask & ~group->mask) 674750a8870SEric Paris fsnotify_recalc_group_mask(group); 675750a8870SEric Paris 67652cef755SEric Paris out_err: 6773dbc6fb6SEric Paris /* match the ref from fsnotify_init_markentry() */ 6783dbc6fb6SEric Paris fsnotify_put_mark(&tmp_ientry->fsn_entry); 67952cef755SEric Paris 68052cef755SEric Paris return ret; 68152cef755SEric Paris } 68252cef755SEric Paris 68352cef755SEric Paris static int inotify_update_watch(struct fsnotify_group *group, struct inode *inode, u32 arg) 68452cef755SEric Paris { 68552cef755SEric Paris int ret = 0; 68652cef755SEric Paris 68752cef755SEric Paris retry: 68852cef755SEric Paris /* try to update and existing watch with the new arg */ 68952cef755SEric Paris ret = inotify_update_existing_watch(group, inode, arg); 69052cef755SEric Paris /* no mark present, try to add a new one */ 69152cef755SEric Paris if (ret == -ENOENT) 69252cef755SEric Paris ret = inotify_new_watch(group, inode, arg); 69352cef755SEric Paris /* 69452cef755SEric Paris * inotify_new_watch could race with another thread which did an 69552cef755SEric Paris * inotify_new_watch between the update_existing and the add watch 69652cef755SEric Paris * here, go back and try to update an existing mark again. 69752cef755SEric Paris */ 69852cef755SEric Paris if (ret == -EEXIST) 69952cef755SEric Paris goto retry; 70052cef755SEric Paris 70163c882a0SEric Paris return ret; 70263c882a0SEric Paris } 70363c882a0SEric Paris 70463c882a0SEric Paris static struct fsnotify_group *inotify_new_group(struct user_struct *user, unsigned int max_events) 70563c882a0SEric Paris { 70663c882a0SEric Paris struct fsnotify_group *group; 70763c882a0SEric Paris unsigned int grp_num; 70863c882a0SEric Paris 70963c882a0SEric Paris /* fsnotify_obtain_group took a reference to group, we put this when we kill the file in the end */ 71063c882a0SEric Paris grp_num = (INOTIFY_GROUP_NUM - atomic_inc_return(&inotify_grp_num)); 71163c882a0SEric Paris group = fsnotify_obtain_group(grp_num, 0, &inotify_fsnotify_ops); 71263c882a0SEric Paris if (IS_ERR(group)) 71363c882a0SEric Paris return group; 71463c882a0SEric Paris 71563c882a0SEric Paris group->max_events = max_events; 71663c882a0SEric Paris 71763c882a0SEric Paris spin_lock_init(&group->inotify_data.idr_lock); 71863c882a0SEric Paris idr_init(&group->inotify_data.idr); 7199e572cc9SEric Paris group->inotify_data.last_wd = 0; 72063c882a0SEric Paris group->inotify_data.user = user; 72163c882a0SEric Paris group->inotify_data.fa = NULL; 72263c882a0SEric Paris 72363c882a0SEric Paris return group; 72463c882a0SEric Paris } 72563c882a0SEric Paris 72663c882a0SEric Paris 72763c882a0SEric Paris /* inotify syscalls */ 728938bb9f5SHeiko Carstens SYSCALL_DEFINE1(inotify_init1, int, flags) 729272eb014SEric Paris { 73063c882a0SEric Paris struct fsnotify_group *group; 731272eb014SEric Paris struct user_struct *user; 732c44dcc56SAl Viro int ret; 733272eb014SEric Paris 734272eb014SEric Paris /* Check the IN_* constants for consistency. */ 735272eb014SEric Paris BUILD_BUG_ON(IN_CLOEXEC != O_CLOEXEC); 736272eb014SEric Paris BUILD_BUG_ON(IN_NONBLOCK != O_NONBLOCK); 737272eb014SEric Paris 738272eb014SEric Paris if (flags & ~(IN_CLOEXEC | IN_NONBLOCK)) 739272eb014SEric Paris return -EINVAL; 740272eb014SEric Paris 741272eb014SEric Paris user = get_current_user(); 742272eb014SEric Paris if (unlikely(atomic_read(&user->inotify_devs) >= 743272eb014SEric Paris inotify_max_user_instances)) { 744272eb014SEric Paris ret = -EMFILE; 745272eb014SEric Paris goto out_free_uid; 746272eb014SEric Paris } 747272eb014SEric Paris 74863c882a0SEric Paris /* fsnotify_obtain_group took a reference to group, we put this when we kill the file in the end */ 74963c882a0SEric Paris group = inotify_new_group(user, inotify_max_queued_events); 75063c882a0SEric Paris if (IS_ERR(group)) { 75163c882a0SEric Paris ret = PTR_ERR(group); 752272eb014SEric Paris goto out_free_uid; 753272eb014SEric Paris } 754272eb014SEric Paris 755825f9692SAl Viro atomic_inc(&user->inotify_devs); 756825f9692SAl Viro 757c44dcc56SAl Viro ret = anon_inode_getfd("inotify", &inotify_fops, group, 758c44dcc56SAl Viro O_RDONLY | flags); 759c44dcc56SAl Viro if (ret >= 0) 760c44dcc56SAl Viro return ret; 761825f9692SAl Viro 762825f9692SAl Viro atomic_dec(&user->inotify_devs); 763272eb014SEric Paris out_free_uid: 764272eb014SEric Paris free_uid(user); 765272eb014SEric Paris return ret; 766272eb014SEric Paris } 767272eb014SEric Paris 768938bb9f5SHeiko Carstens SYSCALL_DEFINE0(inotify_init) 769272eb014SEric Paris { 770272eb014SEric Paris return sys_inotify_init1(0); 771272eb014SEric Paris } 772272eb014SEric Paris 7732e4d0924SHeiko Carstens SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname, 7742e4d0924SHeiko Carstens u32, mask) 775272eb014SEric Paris { 77663c882a0SEric Paris struct fsnotify_group *group; 777272eb014SEric Paris struct inode *inode; 778272eb014SEric Paris struct path path; 779272eb014SEric Paris struct file *filp; 780272eb014SEric Paris int ret, fput_needed; 781272eb014SEric Paris unsigned flags = 0; 782272eb014SEric Paris 783272eb014SEric Paris filp = fget_light(fd, &fput_needed); 784272eb014SEric Paris if (unlikely(!filp)) 785272eb014SEric Paris return -EBADF; 786272eb014SEric Paris 787272eb014SEric Paris /* verify that this is indeed an inotify instance */ 788272eb014SEric Paris if (unlikely(filp->f_op != &inotify_fops)) { 789272eb014SEric Paris ret = -EINVAL; 790272eb014SEric Paris goto fput_and_out; 791272eb014SEric Paris } 792272eb014SEric Paris 793272eb014SEric Paris if (!(mask & IN_DONT_FOLLOW)) 794272eb014SEric Paris flags |= LOOKUP_FOLLOW; 795272eb014SEric Paris if (mask & IN_ONLYDIR) 796272eb014SEric Paris flags |= LOOKUP_DIRECTORY; 797272eb014SEric Paris 79863c882a0SEric Paris ret = inotify_find_inode(pathname, &path, flags); 79963c882a0SEric Paris if (ret) 800272eb014SEric Paris goto fput_and_out; 801272eb014SEric Paris 80263c882a0SEric Paris /* inode held in place by reference to path; group by fget on fd */ 803272eb014SEric Paris inode = path.dentry->d_inode; 80463c882a0SEric Paris group = filp->private_data; 805272eb014SEric Paris 80663c882a0SEric Paris /* create/update an inode mark */ 80763c882a0SEric Paris ret = inotify_update_watch(group, inode, mask); 808272eb014SEric Paris path_put(&path); 809272eb014SEric Paris fput_and_out: 810272eb014SEric Paris fput_light(filp, fput_needed); 811272eb014SEric Paris return ret; 812272eb014SEric Paris } 813272eb014SEric Paris 8142e4d0924SHeiko Carstens SYSCALL_DEFINE2(inotify_rm_watch, int, fd, __s32, wd) 815272eb014SEric Paris { 81663c882a0SEric Paris struct fsnotify_group *group; 817b7ba8371SEric Paris struct inotify_inode_mark_entry *ientry; 818272eb014SEric Paris struct file *filp; 81963c882a0SEric Paris int ret = 0, fput_needed; 820272eb014SEric Paris 821272eb014SEric Paris filp = fget_light(fd, &fput_needed); 822272eb014SEric Paris if (unlikely(!filp)) 823272eb014SEric Paris return -EBADF; 824272eb014SEric Paris 825272eb014SEric Paris /* verify that this is indeed an inotify instance */ 826272eb014SEric Paris ret = -EINVAL; 827b7ba8371SEric Paris if (unlikely(filp->f_op != &inotify_fops)) 828272eb014SEric Paris goto out; 829272eb014SEric Paris 83063c882a0SEric Paris group = filp->private_data; 831272eb014SEric Paris 83263c882a0SEric Paris ret = -EINVAL; 833b7ba8371SEric Paris ientry = inotify_idr_find(group, wd); 834b7ba8371SEric Paris if (unlikely(!ientry)) 83563c882a0SEric Paris goto out; 83663c882a0SEric Paris 837b7ba8371SEric Paris ret = 0; 838b7ba8371SEric Paris 839b7ba8371SEric Paris fsnotify_destroy_mark_by_entry(&ientry->fsn_entry); 840b7ba8371SEric Paris 841b7ba8371SEric Paris /* match ref taken by inotify_idr_find */ 842b7ba8371SEric Paris fsnotify_put_mark(&ientry->fsn_entry); 843272eb014SEric Paris 844272eb014SEric Paris out: 845272eb014SEric Paris fput_light(filp, fput_needed); 846272eb014SEric Paris return ret; 847272eb014SEric Paris } 848272eb014SEric Paris 849272eb014SEric Paris /* 850272eb014SEric Paris * inotify_user_setup - Our initialization function. Note that we cannnot return 851272eb014SEric Paris * error because we have compiled-in VFS hooks. So an (unlikely) failure here 852272eb014SEric Paris * must result in panic(). 853272eb014SEric Paris */ 854272eb014SEric Paris static int __init inotify_user_setup(void) 855272eb014SEric Paris { 85663c882a0SEric Paris inotify_inode_mark_cachep = KMEM_CACHE(inotify_inode_mark_entry, SLAB_PANIC); 85763c882a0SEric Paris event_priv_cachep = KMEM_CACHE(inotify_event_private_data, SLAB_PANIC); 85863c882a0SEric Paris 859272eb014SEric Paris inotify_max_queued_events = 16384; 860272eb014SEric Paris inotify_max_user_instances = 128; 861272eb014SEric Paris inotify_max_user_watches = 8192; 862272eb014SEric Paris 863272eb014SEric Paris return 0; 864272eb014SEric Paris } 865272eb014SEric Paris module_init(inotify_user_setup); 866