| /* |
| * fs/inotify_user.c - inotify support for userspace |
| * |
| * Authors: |
| * John McCutchan <ttb@tentacle.dhs.org> |
| * Robert Love <rml@novell.com> |
| * |
| * Copyright (C) 2005 John McCutchan |
| * Copyright 2006 Hewlett-Packard Development Company, L.P. |
| * |
| * Copyright (C) 2009 Eric Paris <Red Hat Inc> |
| * inotify was largely rewriten to make use of the fsnotify infrastructure |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License as published by the |
| * Free Software Foundation; either version 2, or (at your option) any |
| * later version. |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| */ |
| |
| #include <linux/file.h> |
| #include <linux/fs.h> /* struct inode */ |
| #include <linux/fsnotify_backend.h> |
| #include <linux/idr.h> |
| #include <linux/init.h> /* module_init */ |
| #include <linux/inotify.h> |
| #include <linux/kernel.h> /* roundup() */ |
| #include <linux/magic.h> /* superblock magic number */ |
| #include <linux/mount.h> /* mntget */ |
| #include <linux/namei.h> /* LOOKUP_FOLLOW */ |
| #include <linux/path.h> /* struct path */ |
| #include <linux/sched.h> /* struct user */ |
| #include <linux/slab.h> /* struct kmem_cache */ |
| #include <linux/syscalls.h> |
| #include <linux/types.h> |
| #include <linux/uaccess.h> |
| #include <linux/poll.h> |
| #include <linux/wait.h> |
| |
| #include "inotify.h" |
| |
| #include <asm/ioctls.h> |
| |
| static struct vfsmount *inotify_mnt __read_mostly; |
| |
| /* this just sits here and wastes global memory. used to just pad userspace messages with zeros */ |
| static struct inotify_event nul_inotify_event; |
| |
| /* these are configurable via /proc/sys/fs/inotify/ */ |
| static int inotify_max_user_instances __read_mostly; |
| static int inotify_max_queued_events __read_mostly; |
| int inotify_max_user_watches __read_mostly; |
| |
| static struct kmem_cache *inotify_inode_mark_cachep __read_mostly; |
| struct kmem_cache *event_priv_cachep __read_mostly; |
| static struct fsnotify_event *inotify_ignored_event; |
| |
| /* |
| * When inotify registers a new group it increments this and uses that |
| * value as an offset to set the fsnotify group "name" and priority. |
| */ |
| static atomic_t inotify_grp_num; |
| |
| #ifdef CONFIG_SYSCTL |
| |
| #include <linux/sysctl.h> |
| |
| static int zero; |
| |
| ctl_table inotify_table[] = { |
| { |
| .ctl_name = INOTIFY_MAX_USER_INSTANCES, |
| .procname = "max_user_instances", |
| .data = &inotify_max_user_instances, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = &proc_dointvec_minmax, |
| .strategy = &sysctl_intvec, |
| .extra1 = &zero, |
| }, |
| { |
| .ctl_name = INOTIFY_MAX_USER_WATCHES, |
| .procname = "max_user_watches", |
| .data = &inotify_max_user_watches, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = &proc_dointvec_minmax, |
| .strategy = &sysctl_intvec, |
| .extra1 = &zero, |
| }, |
| { |
| .ctl_name = INOTIFY_MAX_QUEUED_EVENTS, |
| .procname = "max_queued_events", |
| .data = &inotify_max_queued_events, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = &proc_dointvec_minmax, |
| .strategy = &sysctl_intvec, |
| .extra1 = &zero |
| }, |
| { .ctl_name = 0 } |
| }; |
| #endif /* CONFIG_SYSCTL */ |
| |
| static inline __u32 inotify_arg_to_mask(u32 arg) |
| { |
| __u32 mask; |
| |
| /* everything should accept their own ignored and cares about children */ |
| mask = (FS_IN_IGNORED | FS_EVENT_ON_CHILD); |
| |
| /* mask off the flags used to open the fd */ |
| mask |= (arg & (IN_ALL_EVENTS | IN_ONESHOT)); |
| |
| return mask; |
| } |
| |
| static inline u32 inotify_mask_to_arg(__u32 mask) |
| { |
| return mask & (IN_ALL_EVENTS | IN_ISDIR | IN_UNMOUNT | IN_IGNORED | |
| IN_Q_OVERFLOW); |
| } |
| |
| /* intofiy userspace file descriptor functions */ |
| static unsigned int inotify_poll(struct file *file, poll_table *wait) |
| { |
| struct fsnotify_group *group = file->private_data; |
| int ret = 0; |
| |
| poll_wait(file, &group->notification_waitq, wait); |
| mutex_lock(&group->notification_mutex); |
| if (!fsnotify_notify_queue_is_empty(group)) |
| ret = POLLIN | POLLRDNORM; |
| mutex_unlock(&group->notification_mutex); |
| |
| return ret; |
| } |
| |
| /* |
| * Get an inotify_kernel_event if one exists and is small |
| * enough to fit in "count". Return an error pointer if |
| * not large enough. |
| * |
| * Called with the group->notification_mutex held. |
| */ |
| static struct fsnotify_event *get_one_event(struct fsnotify_group *group, |
| size_t count) |
| { |
| size_t event_size = sizeof(struct inotify_event); |
| struct fsnotify_event *event; |
| |
| if (fsnotify_notify_queue_is_empty(group)) |
| return NULL; |
| |
| event = fsnotify_peek_notify_event(group); |
| |
| event_size += roundup(event->name_len, event_size); |
| |
| if (event_size > count) |
| return ERR_PTR(-EINVAL); |
| |
| /* held the notification_mutex the whole time, so this is the |
| * same event we peeked above */ |
| fsnotify_remove_notify_event(group); |
| |
| return event; |
| } |
| |
| /* |
| * Copy an event to user space, returning how much we copied. |
| * |
| * We already checked that the event size is smaller than the |
| * buffer we had in "get_one_event()" above. |
| */ |
| static ssize_t copy_event_to_user(struct fsnotify_group *group, |
| struct fsnotify_event *event, |
| char __user *buf) |
| { |
| struct inotify_event inotify_event; |
| struct fsnotify_event_private_data *fsn_priv; |
| struct inotify_event_private_data *priv; |
| size_t event_size = sizeof(struct inotify_event); |
| size_t name_len; |
| |
| /* we get the inotify watch descriptor from the event private data */ |
| spin_lock(&event->lock); |
| fsn_priv = fsnotify_remove_priv_from_event(group, event); |
| spin_unlock(&event->lock); |
| |
| if (!fsn_priv) |
| inotify_event.wd = -1; |
| else { |
| priv = container_of(fsn_priv, struct inotify_event_private_data, |
| fsnotify_event_priv_data); |
| inotify_event.wd = priv->wd; |
| inotify_free_event_priv(fsn_priv); |
| } |
| |
| /* round up event->name_len so it is a multiple of event_size */ |
| name_len = roundup(event->name_len, event_size); |
| inotify_event.len = name_len; |
| |
| inotify_event.mask = inotify_mask_to_arg(event->mask); |
| inotify_event.cookie = event->sync_cookie; |
| |
| /* send the main event */ |
| if (copy_to_user(buf, &inotify_event, event_size)) |
| return -EFAULT; |
| |
| buf += event_size; |
| |
| /* |
| * fsnotify only stores the pathname, so here we have to send the pathname |
| * and then pad that pathname out to a multiple of sizeof(inotify_event) |
| * with zeros. I get my zeros from the nul_inotify_event. |
| */ |
| if (name_len) { |
| unsigned int len_to_zero = name_len - event->name_len; |
| /* copy the path name */ |
| if (copy_to_user(buf, event->file_name, event->name_len)) |
| return -EFAULT; |
| buf += event->name_len; |
| |
| /* fill userspace with 0's from nul_inotify_event */ |
| if (copy_to_user(buf, &nul_inotify_event, len_to_zero)) |
| return -EFAULT; |
| buf += len_to_zero; |
| event_size += name_len; |
| } |
| |
| return event_size; |
| } |
| |
| static ssize_t inotify_read(struct file *file, char __user *buf, |
| size_t count, loff_t *pos) |
| { |
| struct fsnotify_group *group; |
| struct fsnotify_event *kevent; |
| char __user *start; |
| int ret; |
| DEFINE_WAIT(wait); |
| |
| start = buf; |
| group = file->private_data; |
| |
| while (1) { |
| prepare_to_wait(&group->notification_waitq, &wait, TASK_INTERRUPTIBLE); |
| |
| mutex_lock(&group->notification_mutex); |
| kevent = get_one_event(group, count); |
| mutex_unlock(&group->notification_mutex); |
| |
| if (kevent) { |
| ret = PTR_ERR(kevent); |
| if (IS_ERR(kevent)) |
| break; |
| ret = copy_event_to_user(group, kevent, buf); |
| fsnotify_put_event(kevent); |
| if (ret < 0) |
| break; |
| buf += ret; |
| count -= ret; |
| continue; |
| } |
| |
| ret = -EAGAIN; |
| if (file->f_flags & O_NONBLOCK) |
| break; |
| ret = -EINTR; |
| if (signal_pending(current)) |
| break; |
| |
| if (start != buf) |
| break; |
| |
| schedule(); |
| } |
| |
| finish_wait(&group->notification_waitq, &wait); |
| if (start != buf && ret != -EFAULT) |
| ret = buf - start; |
| return ret; |
| } |
| |
| static int inotify_fasync(int fd, struct file *file, int on) |
| { |
| struct fsnotify_group *group = file->private_data; |
| |
| return fasync_helper(fd, file, on, &group->inotify_data.fa) >= 0 ? 0 : -EIO; |
| } |
| |
| static int inotify_release(struct inode *ignored, struct file *file) |
| { |
| struct fsnotify_group *group = file->private_data; |
| |
| fsnotify_clear_marks_by_group(group); |
| |
| /* free this group, matching get was inotify_init->fsnotify_obtain_group */ |
| fsnotify_put_group(group); |
| |
| return 0; |
| } |
| |
| static long inotify_ioctl(struct file *file, unsigned int cmd, |
| unsigned long arg) |
| { |
| struct fsnotify_group *group; |
| struct fsnotify_event_holder *holder; |
| struct fsnotify_event *event; |
| void __user *p; |
| int ret = -ENOTTY; |
| size_t send_len = 0; |
| |
| group = file->private_data; |
| p = (void __user *) arg; |
| |
| switch (cmd) { |
| case FIONREAD: |
| mutex_lock(&group->notification_mutex); |
| list_for_each_entry(holder, &group->notification_list, event_list) { |
| event = holder->event; |
| send_len += sizeof(struct inotify_event); |
| send_len += roundup(event->name_len, |
| sizeof(struct inotify_event)); |
| } |
| mutex_unlock(&group->notification_mutex); |
| ret = put_user(send_len, (int __user *) p); |
| break; |
| } |
| |
| return ret; |
| } |
| |
| static const struct file_operations inotify_fops = { |
| .poll = inotify_poll, |
| .read = inotify_read, |
| .fasync = inotify_fasync, |
| .release = inotify_release, |
| .unlocked_ioctl = inotify_ioctl, |
| .compat_ioctl = inotify_ioctl, |
| }; |
| |
| |
| /* |
| * find_inode - resolve a user-given path to a specific inode |
| */ |
| static int inotify_find_inode(const char __user *dirname, struct path *path, unsigned flags) |
| { |
| int error; |
| |
| error = user_path_at(AT_FDCWD, dirname, flags, path); |
| if (error) |
| return error; |
| /* you can only watch an inode if you have read permissions on it */ |
| error = inode_permission(path->dentry->d_inode, MAY_READ); |
| if (error) |
| path_put(path); |
| return error; |
| } |
| |
| /* |
| * When, for whatever reason, inotify is done with a mark (or what used to be a |
| * watch) we need to remove that watch from the idr and we need to send IN_IGNORED |
| * for the given wd. |
| * |
| * There is a bit of recursion here. The loop looks like: |
| * inotify_destroy_mark_entry -> fsnotify_destroy_mark_by_entry -> |
| * inotify_freeing_mark -> inotify_destory_mark_entry -> restart |
| * But the loop is broken in 2 places. fsnotify_destroy_mark_by_entry sets |
| * entry->group = NULL before the call to inotify_freeing_mark, so the if (egroup) |
| * test below will not call back to fsnotify again. But even if that test wasn't |
| * there this would still be safe since fsnotify_destroy_mark_by_entry() is |
| * safe from recursion. |
| */ |
| void inotify_destroy_mark_entry(struct fsnotify_mark_entry *entry, struct fsnotify_group *group) |
| { |
| struct inotify_inode_mark_entry *ientry; |
| struct inotify_event_private_data *event_priv; |
| struct fsnotify_event_private_data *fsn_event_priv; |
| struct fsnotify_group *egroup; |
| struct idr *idr; |
| |
| spin_lock(&entry->lock); |
| egroup = entry->group; |
| |
| /* if egroup we aren't really done and something might still send events |
| * for this inode, on the callback we'll send the IN_IGNORED */ |
| if (egroup) { |
| spin_unlock(&entry->lock); |
| fsnotify_destroy_mark_by_entry(entry); |
| return; |
| } |
| spin_unlock(&entry->lock); |
| |
| ientry = container_of(entry, struct inotify_inode_mark_entry, fsn_entry); |
| |
| event_priv = kmem_cache_alloc(event_priv_cachep, GFP_KERNEL); |
| if (unlikely(!event_priv)) |
| goto skip_send_ignore; |
| |
| fsn_event_priv = &event_priv->fsnotify_event_priv_data; |
| |
| fsn_event_priv->group = group; |
| event_priv->wd = ientry->wd; |
| |
| fsnotify_add_notify_event(group, inotify_ignored_event, fsn_event_priv); |
| |
| /* did the private data get added? */ |
| if (list_empty(&fsn_event_priv->event_list)) |
| inotify_free_event_priv(fsn_event_priv); |
| |
| skip_send_ignore: |
| |
| /* remove this entry from the idr */ |
| spin_lock(&group->inotify_data.idr_lock); |
| idr = &group->inotify_data.idr; |
| idr_remove(idr, ientry->wd); |
| spin_unlock(&group->inotify_data.idr_lock); |
| |
| /* removed from idr, drop that reference */ |
| fsnotify_put_mark(entry); |
| } |
| |
| /* ding dong the mark is dead */ |
| static void inotify_free_mark(struct fsnotify_mark_entry *entry) |
| { |
| struct inotify_inode_mark_entry *ientry = (struct inotify_inode_mark_entry *)entry; |
| |
| kmem_cache_free(inotify_inode_mark_cachep, ientry); |
| } |
| |
| static int inotify_update_watch(struct fsnotify_group *group, struct inode *inode, u32 arg) |
| { |
| struct fsnotify_mark_entry *entry = NULL; |
| struct inotify_inode_mark_entry *ientry; |
| int ret = 0; |
| int add = (arg & IN_MASK_ADD); |
| __u32 mask; |
| __u32 old_mask, new_mask; |
| |
| /* don't allow invalid bits: we don't want flags set */ |
| mask = inotify_arg_to_mask(arg); |
| if (unlikely(!mask)) |
| return -EINVAL; |
| |
| ientry = kmem_cache_alloc(inotify_inode_mark_cachep, GFP_KERNEL); |
| if (unlikely(!ientry)) |
| return -ENOMEM; |
| /* we set the mask at the end after attaching it */ |
| fsnotify_init_mark(&ientry->fsn_entry, inotify_free_mark); |
| ientry->wd = 0; |
| |
| find_entry: |
| spin_lock(&inode->i_lock); |
| entry = fsnotify_find_mark_entry(group, inode); |
| spin_unlock(&inode->i_lock); |
| if (entry) { |
| kmem_cache_free(inotify_inode_mark_cachep, ientry); |
| ientry = container_of(entry, struct inotify_inode_mark_entry, fsn_entry); |
| } else { |
| if (atomic_read(&group->inotify_data.user->inotify_watches) >= inotify_max_user_watches) { |
| ret = -ENOSPC; |
| goto out_err; |
| } |
| |
| ret = fsnotify_add_mark(&ientry->fsn_entry, group, inode); |
| if (ret == -EEXIST) |
| goto find_entry; |
| else if (ret) |
| goto out_err; |
| |
| entry = &ientry->fsn_entry; |
| retry: |
| ret = -ENOMEM; |
| if (unlikely(!idr_pre_get(&group->inotify_data.idr, GFP_KERNEL))) |
| goto out_err; |
| |
| spin_lock(&group->inotify_data.idr_lock); |
| /* if entry is added to the idr we keep the reference obtained |
| * through fsnotify_mark_add. remember to drop this reference |
| * when entry is removed from idr */ |
| ret = idr_get_new_above(&group->inotify_data.idr, entry, |
| ++group->inotify_data.last_wd, |
| &ientry->wd); |
| spin_unlock(&group->inotify_data.idr_lock); |
| if (ret) { |
| if (ret == -EAGAIN) |
| goto retry; |
| goto out_err; |
| } |
| atomic_inc(&group->inotify_data.user->inotify_watches); |
| } |
| |
| spin_lock(&entry->lock); |
| |
| old_mask = entry->mask; |
| if (add) { |
| entry->mask |= mask; |
| new_mask = entry->mask; |
| } else { |
| entry->mask = mask; |
| new_mask = entry->mask; |
| } |
| |
| spin_unlock(&entry->lock); |
| |
| if (old_mask != new_mask) { |
| /* more bits in old than in new? */ |
| int dropped = (old_mask & ~new_mask); |
| /* more bits in this entry than the inode's mask? */ |
| int do_inode = (new_mask & ~inode->i_fsnotify_mask); |
| /* more bits in this entry than the group? */ |
| int do_group = (new_mask & ~group->mask); |
| |
| /* update the inode with this new entry */ |
| if (dropped || do_inode) |
| fsnotify_recalc_inode_mask(inode); |
| |
| /* update the group mask with the new mask */ |
| if (dropped || do_group) |
| fsnotify_recalc_group_mask(group); |
| } |
| |
| return ientry->wd; |
| |
| out_err: |
| /* see this isn't supposed to happen, just kill the watch */ |
| if (entry) { |
| fsnotify_destroy_mark_by_entry(entry); |
| fsnotify_put_mark(entry); |
| } |
| return ret; |
| } |
| |
| static struct fsnotify_group *inotify_new_group(struct user_struct *user, unsigned int max_events) |
| { |
| struct fsnotify_group *group; |
| unsigned int grp_num; |
| |
| /* fsnotify_obtain_group took a reference to group, we put this when we kill the file in the end */ |
| grp_num = (INOTIFY_GROUP_NUM - atomic_inc_return(&inotify_grp_num)); |
| group = fsnotify_obtain_group(grp_num, 0, &inotify_fsnotify_ops); |
| if (IS_ERR(group)) |
| return group; |
| |
| group->max_events = max_events; |
| |
| spin_lock_init(&group->inotify_data.idr_lock); |
| idr_init(&group->inotify_data.idr); |
| group->inotify_data.last_wd = 0; |
| group->inotify_data.user = user; |
| group->inotify_data.fa = NULL; |
| |
| return group; |
| } |
| |
| |
| /* inotify syscalls */ |
| SYSCALL_DEFINE1(inotify_init1, int, flags) |
| { |
| struct fsnotify_group *group; |
| struct user_struct *user; |
| struct file *filp; |
| int fd, ret; |
| |
| /* Check the IN_* constants for consistency. */ |
| BUILD_BUG_ON(IN_CLOEXEC != O_CLOEXEC); |
| BUILD_BUG_ON(IN_NONBLOCK != O_NONBLOCK); |
| |
| if (flags & ~(IN_CLOEXEC | IN_NONBLOCK)) |
| return -EINVAL; |
| |
| fd = get_unused_fd_flags(flags & O_CLOEXEC); |
| if (fd < 0) |
| return fd; |
| |
| filp = get_empty_filp(); |
| if (!filp) { |
| ret = -ENFILE; |
| goto out_put_fd; |
| } |
| |
| user = get_current_user(); |
| if (unlikely(atomic_read(&user->inotify_devs) >= |
| inotify_max_user_instances)) { |
| ret = -EMFILE; |
| goto out_free_uid; |
| } |
| |
| /* fsnotify_obtain_group took a reference to group, we put this when we kill the file in the end */ |
| group = inotify_new_group(user, inotify_max_queued_events); |
| if (IS_ERR(group)) { |
| ret = PTR_ERR(group); |
| goto out_free_uid; |
| } |
| |
| filp->f_op = &inotify_fops; |
| filp->f_path.mnt = mntget(inotify_mnt); |
| filp->f_path.dentry = dget(inotify_mnt->mnt_root); |
| filp->f_mapping = filp->f_path.dentry->d_inode->i_mapping; |
| filp->f_mode = FMODE_READ; |
| filp->f_flags = O_RDONLY | (flags & O_NONBLOCK); |
| filp->private_data = group; |
| |
| atomic_inc(&user->inotify_devs); |
| |
| fd_install(fd, filp); |
| |
| return fd; |
| |
| out_free_uid: |
| free_uid(user); |
| put_filp(filp); |
| out_put_fd: |
| put_unused_fd(fd); |
| return ret; |
| } |
| |
| SYSCALL_DEFINE0(inotify_init) |
| { |
| return sys_inotify_init1(0); |
| } |
| |
| SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname, |
| u32, mask) |
| { |
| struct fsnotify_group *group; |
| struct inode *inode; |
| struct path path; |
| struct file *filp; |
| int ret, fput_needed; |
| unsigned flags = 0; |
| |
| filp = fget_light(fd, &fput_needed); |
| if (unlikely(!filp)) |
| return -EBADF; |
| |
| /* verify that this is indeed an inotify instance */ |
| if (unlikely(filp->f_op != &inotify_fops)) { |
| ret = -EINVAL; |
| goto fput_and_out; |
| } |
| |
| if (!(mask & IN_DONT_FOLLOW)) |
| flags |= LOOKUP_FOLLOW; |
| if (mask & IN_ONLYDIR) |
| flags |= LOOKUP_DIRECTORY; |
| |
| ret = inotify_find_inode(pathname, &path, flags); |
| if (ret) |
| goto fput_and_out; |
| |
| /* inode held in place by reference to path; group by fget on fd */ |
| inode = path.dentry->d_inode; |
| group = filp->private_data; |
| |
| /* create/update an inode mark */ |
| ret = inotify_update_watch(group, inode, mask); |
| if (unlikely(ret)) |
| goto path_put_and_out; |
| |
| path_put_and_out: |
| path_put(&path); |
| fput_and_out: |
| fput_light(filp, fput_needed); |
| return ret; |
| } |
| |
| SYSCALL_DEFINE2(inotify_rm_watch, int, fd, __s32, wd) |
| { |
| struct fsnotify_group *group; |
| struct fsnotify_mark_entry *entry; |
| struct file *filp; |
| int ret = 0, fput_needed; |
| |
| filp = fget_light(fd, &fput_needed); |
| if (unlikely(!filp)) |
| return -EBADF; |
| |
| /* verify that this is indeed an inotify instance */ |
| if (unlikely(filp->f_op != &inotify_fops)) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| group = filp->private_data; |
| |
| spin_lock(&group->inotify_data.idr_lock); |
| entry = idr_find(&group->inotify_data.idr, wd); |
| if (unlikely(!entry)) { |
| spin_unlock(&group->inotify_data.idr_lock); |
| ret = -EINVAL; |
| goto out; |
| } |
| fsnotify_get_mark(entry); |
| spin_unlock(&group->inotify_data.idr_lock); |
| |
| inotify_destroy_mark_entry(entry, group); |
| fsnotify_put_mark(entry); |
| |
| out: |
| fput_light(filp, fput_needed); |
| return ret; |
| } |
| |
| static int |
| inotify_get_sb(struct file_system_type *fs_type, int flags, |
| const char *dev_name, void *data, struct vfsmount *mnt) |
| { |
| return get_sb_pseudo(fs_type, "inotify", NULL, |
| INOTIFYFS_SUPER_MAGIC, mnt); |
| } |
| |
| static struct file_system_type inotify_fs_type = { |
| .name = "inotifyfs", |
| .get_sb = inotify_get_sb, |
| .kill_sb = kill_anon_super, |
| }; |
| |
| /* |
| * inotify_user_setup - Our initialization function. Note that we cannnot return |
| * error because we have compiled-in VFS hooks. So an (unlikely) failure here |
| * must result in panic(). |
| */ |
| static int __init inotify_user_setup(void) |
| { |
| int ret; |
| |
| ret = register_filesystem(&inotify_fs_type); |
| if (unlikely(ret)) |
| panic("inotify: register_filesystem returned %d!\n", ret); |
| |
| inotify_mnt = kern_mount(&inotify_fs_type); |
| if (IS_ERR(inotify_mnt)) |
| panic("inotify: kern_mount ret %ld!\n", PTR_ERR(inotify_mnt)); |
| |
| inotify_inode_mark_cachep = KMEM_CACHE(inotify_inode_mark_entry, SLAB_PANIC); |
| event_priv_cachep = KMEM_CACHE(inotify_event_private_data, SLAB_PANIC); |
| inotify_ignored_event = fsnotify_create_event(NULL, FS_IN_IGNORED, NULL, FSNOTIFY_EVENT_NONE, NULL, 0); |
| if (!inotify_ignored_event) |
| panic("unable to allocate the inotify ignored event\n"); |
| |
| inotify_max_queued_events = 16384; |
| inotify_max_user_instances = 128; |
| inotify_max_user_watches = 8192; |
| |
| return 0; |
| } |
| module_init(inotify_user_setup); |