From: Robert Love inotify is intended to correct the deficiencies of dnotify: * dnotify requires the opening of one fd per each directory that you intend to watch. This quickly results in too many open files and pins removable media, preventing unmount. * dnotify is directory-based. You only learn about changes to directories. Sure, a change to a file in a directory affects the directory, but you are then forced to keep a cache of stat structures. * dnotify's interface to user-space is awful. Signals? inotify provides a more usable, simple, powerful solution to file change notification: * inotify's interface is a device node, not SIGIO. You open a single fd to the device node, which is select()-able. * inotify has an event that says "the filesystem that the item you were watching is on was unmounted." * inotify can watch directories or files. The primary change since the last post is a reworking of the locking and refcounting. A bit more such reworking is expected. Inotify is currently used by Beagle (a desktop search infrastructure) and Gamin (a FAM replacement). Signed-off-by: Robert Love Signed-off-by: Andrew Morton --- 25-akpm/drivers/char/Kconfig | 13 25-akpm/drivers/char/Makefile | 2 25-akpm/drivers/char/inotify.c | 1024 +++++++++++++++++++++++++++++++++++++ 25-akpm/fs/attr.c | 73 +- 25-akpm/fs/file_table.c | 7 25-akpm/fs/inode.c | 3 25-akpm/fs/namei.c | 35 + 25-akpm/fs/open.c | 5 25-akpm/fs/read_write.c | 27 25-akpm/fs/super.c | 2 25-akpm/include/linux/fs.h | 7 25-akpm/include/linux/inotify.h | 155 +++++ 25-akpm/include/linux/miscdevice.h | 1 25-akpm/include/linux/sched.h | 2 25-akpm/kernel/user.c | 2 15 files changed, 1331 insertions(+), 27 deletions(-) diff -puN /dev/null drivers/char/inotify.c --- /dev/null 2003-09-15 06:40:47.000000000 -0700 +++ 25-akpm/drivers/char/inotify.c 2005-01-13 23:04:31.504043648 -0800 @@ -0,0 +1,1024 @@ +/* + * Inode based directory notifications for Linux. + * + * Copyright (C) 2004 John McCutchan + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +static atomic_t inotify_cookie; +static kmem_cache_t *watch_cachep; +static kmem_cache_t *event_cachep; +static kmem_cache_t *inode_data_cachep; + +static int sysfs_attrib_max_user_devices; +static int sysfs_attrib_max_user_watches; +static unsigned int sysfs_attrib_max_queued_events; + +/* + * struct inotify_device - represents an open instance of an inotify device + * + * For each inotify device, we need to keep track of the events queued on it, + * a list of the inodes that we are watching, and so on. + * + * This structure is protected by 'lock'. Lock ordering: + * + * dev->lock (protects dev) + * inode_lock (used to safely walk inode_in_use list) + * inode->i_lock (only needed for getting ref on inode_data) + */ +struct inotify_device { + wait_queue_head_t wait; + struct idr idr; + struct list_head events; + struct list_head watches; + spinlock_t lock; + unsigned int event_count; + unsigned int max_events; + struct user_struct *user; +}; + +struct inotify_watch { + s32 wd; /* watch descriptor */ + u32 mask; + struct inode *inode; + struct inotify_device *dev; + struct list_head d_list; /* device list */ + struct list_head i_list; /* inode list */ +}; + +static ssize_t show_max_queued_events(struct class_device *class, char *buf) +{ + return sprintf(buf, "%d\n", sysfs_attrib_max_queued_events); +} + +static ssize_t store_max_queued_events(struct class_device *class, + const char *buf, size_t count) +{ + unsigned int max; + + if (sscanf(buf, "%u", &max) > 0 && max > 0) { + sysfs_attrib_max_queued_events = max; + return strlen(buf); + } + return -EINVAL; +} + +static ssize_t show_max_user_devices(struct class_device *class, char *buf) +{ + return sprintf(buf, "%d\n", sysfs_attrib_max_user_devices); +} + +static ssize_t store_max_user_devices(struct class_device *class, + const char *buf, size_t count) +{ + int max; + + if (sscanf(buf, "%d", &max) > 0 && max > 0) { + sysfs_attrib_max_user_devices = max; + return strlen(buf); + } + return -EINVAL; +} + +static ssize_t show_max_user_watches(struct class_device *class, char *buf) +{ + return sprintf(buf, "%d\n", sysfs_attrib_max_user_watches); +} + +static ssize_t store_max_user_watches(struct class_device *class, + const char *buf, size_t count) +{ + int max; + + if (sscanf(buf, "%d", &max) > 0 && max > 0) { + sysfs_attrib_max_user_watches = max; + return strlen(buf); + } + return -EINVAL; +} + +static CLASS_DEVICE_ATTR(max_queued_events, S_IRUGO | S_IWUSR, + show_max_queued_events, store_max_queued_events); +static CLASS_DEVICE_ATTR(max_user_devices, S_IRUGO | S_IWUSR, + show_max_user_devices, store_max_user_devices); +static CLASS_DEVICE_ATTR(max_user_watches, S_IRUGO | S_IWUSR, + show_max_user_watches, store_max_user_watches); + +/* + * A list of these is attached to each instance of the driver + * when the drivers read() gets called, this list is walked and + * all events that can fit in the buffer get delivered + */ +struct inotify_kernel_event { + struct list_head list; + struct inotify_event event; +}; + +static inline void __get_inode_data(struct inotify_inode_data *data) +{ + atomic_inc(&data->count); +} + +/* + * get_inode_data - pin an inotify_inode_data structure. Returns the structure + * if successful and NULL on failure, which can only occur if inotify_data is + * not yet allocated. The inode must be pinned prior to invocation. + */ +static inline struct inotify_inode_data * get_inode_data(struct inode *inode) +{ + struct inotify_inode_data *data; + + spin_lock(&inode->i_lock); + data = inode->inotify_data; + if (data) + __get_inode_data(data); + spin_unlock(&inode->i_lock); + + return data; +} + +/* + * put_inode_data - drop our reference on an inotify_inode_data and the + * inode structure in which it lives. If the reference count on inotify_data + * reaches zero, free it. + */ +static inline void put_inode_data(struct inode *inode) +{ + //spin_lock(&inode->i_lock); + if (atomic_dec_and_test(&inode->inotify_data->count)) { + kmem_cache_free(inode_data_cachep, inode->inotify_data); + inode->inotify_data = NULL; + } + //spin_unlock(&inode->i_lock); +} + +/* + * find_inode - resolve a user-given path to a specific inode and iget() it + */ +static struct inode * find_inode(const char __user *dirname) +{ + struct inode *inode; + struct nameidata nd; + int error; + + error = __user_walk(dirname, LOOKUP_FOLLOW, &nd); + if (error) + return ERR_PTR(error); + + inode = nd.dentry->d_inode; + + /* you can only watch an inode if you have read permissions on it */ + error = permission(inode, MAY_READ, NULL); + if (error) { + inode = ERR_PTR(error); + goto release_and_out; + } + + spin_lock(&inode_lock); + __iget(inode); + spin_unlock(&inode_lock); +release_and_out: + path_release(&nd); + return inode; +} + +struct inotify_kernel_event * kernel_event(s32 wd, u32 mask, u32 cookie, + const char *filename) +{ + struct inotify_kernel_event *kevent; + + kevent = kmem_cache_alloc(event_cachep, GFP_ATOMIC); + if (!kevent) + return NULL; + + /* we hand this out to user-space, so zero it out just in case */ + memset(kevent, 0, sizeof(struct inotify_kernel_event)); + + kevent->event.wd = wd; + kevent->event.mask = mask; + kevent->event.cookie = cookie; + INIT_LIST_HEAD(&kevent->list); + + if (filename) { + strncpy(kevent->event.filename, filename, INOTIFY_FILENAME_MAX); + kevent->event.filename[INOTIFY_FILENAME_MAX-1] = '\0'; + } else + kevent->event.filename[0] = '\0'; + + return kevent; +} + +void delete_kernel_event(struct inotify_kernel_event *kevent) +{ + if (!kevent) + return; + kmem_cache_free(event_cachep, kevent); +} + +#define list_to_inotify_kernel_event(pos) \ + list_entry((pos), struct inotify_kernel_event, list) + +#define inotify_dev_get_event(dev) \ + (list_to_inotify_kernel_event(dev->events.next)) + +/* Does this events mask get sent to the watch ? */ +#define event_and(event_mask,watches_mask) ((event_mask == IN_UNMOUNT) || \ + (event_mask == IN_IGNORED) || \ + (event_mask & watches_mask)) + +/* + * inotify_dev_queue_event - add a new event to the given device + * + * Caller must hold dev->lock. + */ +static void inotify_dev_queue_event(struct inotify_device *dev, + struct inotify_watch *watch, u32 mask, + u32 cookie, const char *filename) +{ + struct inotify_kernel_event *kevent, *last; + + /* Check if the new event is a duplicate of the last event queued. */ + last = inotify_dev_get_event(dev); + if (dev->event_count && last->event.mask == mask && + last->event.wd == watch->wd) { + /* Check if the filenames match */ + if (!filename && last->event.filename[0] == '\0') + return; + if (filename && !strcmp(last->event.filename, filename)) + return; + } + + /* + * the queue has already overflowed and we have already sent the + * Q_OVERFLOW event + */ + if (dev->event_count > dev->max_events) + return; + + /* the queue has just overflowed and we need to notify user space */ + if (dev->event_count == dev->max_events) { + kevent = kernel_event(-1, IN_Q_OVERFLOW, cookie, NULL); + goto add_event_to_queue; + } + + if (!event_and(mask, watch->inode->inotify_data->watch_mask) || + !event_and(mask, watch->mask)) + return; + + kevent = kernel_event(watch->wd, mask, cookie, filename); + +add_event_to_queue: + if (!kevent) + return; + + /* queue the event and wake up anyone waiting */ + dev->event_count++; + list_add_tail(&kevent->list, &dev->events); + wake_up_interruptible(&dev->wait); +} + +static inline int inotify_dev_has_events(struct inotify_device *dev) +{ + return !list_empty(&dev->events); +} + +/* + * inotify_dev_event_dequeue - destroy an event on the given device + * + * Caller must hold dev->lock. + */ +static void inotify_dev_event_dequeue(struct inotify_device *dev) +{ + struct inotify_kernel_event *kevent; + + if (!inotify_dev_has_events(dev)) + return; + + kevent = inotify_dev_get_event(dev); + list_del_init(&kevent->list); + dev->event_count--; + delete_kernel_event(kevent); +} + +/* + * inotify_dev_get_wd - returns the next WD for use by the given dev + * + * This function can sleep. + */ +static int inotify_dev_get_wd(struct inotify_device *dev, + struct inotify_watch *watch) +{ + int ret; + + if (atomic_read(&dev->user->inotify_watches) >= + sysfs_attrib_max_user_watches) + return -ENOSPC; + +repeat: + if (!idr_pre_get(&dev->idr, GFP_KERNEL)) + return -ENOSPC; + spin_lock(&dev->lock); + ret = idr_get_new(&dev->idr, watch, &watch->wd); + spin_unlock(&dev->lock); + if (ret == -EAGAIN) /* more memory is required, try again */ + goto repeat; + else if (ret) /* the idr is full! */ + return -ENOSPC; + + atomic_inc(&dev->user->inotify_watches); + + return 0; +} + +/* + * inotify_dev_put_wd - release the given WD on the given device + * + * Caller must hold dev->lock. + */ +static int inotify_dev_put_wd(struct inotify_device *dev, s32 wd) +{ + if (!dev || wd < 0) + return -1; + + atomic_dec(&dev->user->inotify_watches); + idr_remove(&dev->idr, wd); + + return 0; +} + +/* + * create_watch - creates a watch on the given device. + * + * Grabs dev->lock, so the caller must not hold it. + */ +static struct inotify_watch *create_watch(struct inotify_device *dev, + u32 mask, struct inode *inode) +{ + struct inotify_watch *watch; + + watch = kmem_cache_alloc(watch_cachep, GFP_KERNEL); + if (!watch) + return NULL; + + watch->mask = mask; + watch->inode = inode; + watch->dev = dev; + INIT_LIST_HEAD(&watch->d_list); + INIT_LIST_HEAD(&watch->i_list); + + if (inotify_dev_get_wd(dev, watch)) { + kmem_cache_free(watch_cachep, watch); + return NULL; + } + + return watch; +} + +/* + * delete_watch - removes the given 'watch' from the given 'dev' + * + * Caller must hold dev->lock. + */ +static void delete_watch(struct inotify_device *dev, + struct inotify_watch *watch) +{ + inotify_dev_put_wd(dev, watch->wd); + kmem_cache_free(watch_cachep, watch); +} + +/* + * inotify_find_dev - find the watch associated with the given inode and dev + * + * Caller must hold dev->lock. + * FIXME: Needs inotify_data->lock too. Don't need dev->lock, just pin it. + */ +static struct inotify_watch *inode_find_dev(struct inode *inode, + struct inotify_device *dev) +{ + struct inotify_watch *watch; + + if (!inode->inotify_data) + return NULL; + + list_for_each_entry(watch, &inode->inotify_data->watches, i_list) { + if (watch->dev == dev) + return watch; + } + + return NULL; +} + +/* + * dev_find_wd - given a (dev,wd) pair, returns the matching inotify_watcher + * + * Returns the results of looking up (dev,wd) in the idr layer. NULL is + * returned on error. + * + * The caller must hold dev->lock. + */ +static inline struct inotify_watch *dev_find_wd(struct inotify_device *dev, + u32 wd) +{ + return idr_find(&dev->idr, wd); +} + +static int inotify_dev_is_watching_inode(struct inotify_device *dev, + struct inode *inode) +{ + struct inotify_watch *watch; + + list_for_each_entry(watch, &dev->watches, d_list) { + if (watch->inode == inode) + return 1; + } + + return 0; +} + +/* + * inotify_dev_add_watcher - add the given watcher to the given device instance + * + * Caller must hold dev->lock. + */ +static int inotify_dev_add_watch(struct inotify_device *dev, + struct inotify_watch *watch) +{ + if (!dev || !watch) + return -EINVAL; + + list_add(&watch->d_list, &dev->watches); + return 0; +} + +/* + * inotify_dev_rm_watch - remove the given watch from the given device + * + * Caller must hold dev->lock because we call inotify_dev_queue_event(). + */ +static int inotify_dev_rm_watch(struct inotify_device *dev, + struct inotify_watch *watch) +{ + if (!watch) + return -EINVAL; + + inotify_dev_queue_event(dev, watch, IN_IGNORED, 0, NULL); + list_del_init(&watch->d_list); + + return 0; +} + +/* + * inode_update_watch_mask - update inode->inotify_data->watch_mask + * + * Grabs inode->inotify_data->lock. + */ +static void inode_update_watch_mask(struct inode *inode) +{ + struct inotify_inode_data *data; + struct inotify_watch *watch; + u32 new_mask; + + data = get_inode_data(inode); + if (!data) /* FIXME: this should never happen */ + return; + spin_lock(&data->lock); + + new_mask = 0; + list_for_each_entry(watch, &data->watches, i_list) + new_mask |= watch->mask; + + data->watch_mask = new_mask; + + spin_unlock(&data->lock); + put_inode_data(inode); +} + +/* + * inode_add_watch - add a watch to the given inode + * + * Callers must hold dev->lock, because we call inode_find_dev(). + */ +static int inode_add_watch(struct inode *inode, struct inotify_watch *watch) +{ + int ret; + + if (!inode || !watch) + return -EINVAL; + + spin_lock(&inode->i_lock); + if (!inode->inotify_data) { + /* inotify_data is not attached to the inode, so add it */ + inode->inotify_data = kmem_cache_alloc(inode_data_cachep, + GFP_ATOMIC); + if (!inode->inotify_data) { + ret = -ENOMEM; + goto out_lock; + } + + atomic_set(&inode->inotify_data->count, 0); + INIT_LIST_HEAD(&inode->inotify_data->watches); + inode->inotify_data->watch_mask = 0; + spin_lock_init(&inode->inotify_data->lock); + } else if (inode_find_dev(inode, watch->dev)) { + /* a watch is already associated with this (inode,dev) pair */ + ret = -EINVAL; + goto out_lock; + } + __get_inode_data(inode->inotify_data); + spin_unlock(&inode->i_lock); + + list_add(&watch->i_list, &inode->inotify_data->watches); + inode_update_watch_mask(inode); + + return 0; +out_lock: + spin_unlock(&inode->i_lock); + return ret; +} + +static int inode_rm_watch(struct inode *inode, + struct inotify_watch *watch) +{ + if (!inode || !watch || !inode->inotify_data) + return -EINVAL; + + list_del_init(&watch->i_list); + inode_update_watch_mask(inode); + + /* clean up inode->inotify_data */ + put_inode_data(inode); + + return 0; +} + +/* Kernel API */ + +/* + * inotify_inode_queue_event - queue an event with the given mask, cookie, and + * filename to any watches associated with the given inode. + * + * inode must be pinned prior to calling. + */ +void inotify_inode_queue_event(struct inode *inode, u32 mask, u32 cookie, + const char *filename) +{ + struct inotify_watch *watch; + + if (!inode->inotify_data) + return; + + list_for_each_entry(watch, &inode->inotify_data->watches, i_list) { + spin_lock(&watch->dev->lock); + inotify_dev_queue_event(watch->dev, watch, mask, cookie, + filename); + spin_unlock(&watch->dev->lock); + } +} +EXPORT_SYMBOL_GPL(inotify_inode_queue_event); + +void inotify_dentry_parent_queue_event(struct dentry *dentry, u32 mask, + u32 cookie, const char *filename) +{ + struct dentry *parent; + + parent = dget_parent(dentry); + inotify_inode_queue_event(parent->d_inode, mask, cookie, filename); + dput(parent); +} +EXPORT_SYMBOL_GPL(inotify_dentry_parent_queue_event); + +u32 inotify_get_cookie(void) +{ + atomic_inc(&inotify_cookie); + return atomic_read(&inotify_cookie); +} +EXPORT_SYMBOL_GPL(inotify_get_cookie); + +/* + * watch->inode must be pinned. We drop a reference before returning. + */ +static void ignore_helper(struct inotify_watch *watch, int event) +{ + struct inotify_device *dev; + struct inode *inode; + + inode = watch->inode; + dev = watch->dev; + + spin_lock(&dev->lock); + + if (event) + inotify_dev_queue_event(dev, watch, event, 0, NULL); + + inode_rm_watch(inode, watch); + inotify_dev_rm_watch(watch->dev, watch); + + delete_watch(dev, watch); + spin_unlock(&dev->lock); + + iput(inode); +} + +void inotify_super_block_umount(struct super_block *sb) +{ + struct inode *inode; + + spin_lock(&inode_lock); + + /* + * We hold the inode_lock, so the inodes are not going anywhere, and + * we grab a reference on inotify_data before walking its list of + * watches. + */ + list_for_each_entry(inode, &inode_in_use, i_list) { + struct inotify_inode_data *inode_data; + struct inotify_watch *watch; + + if (inode->i_sb != sb) + continue; + + inode_data = get_inode_data(inode); + if (!inode_data) + continue; + + list_for_each_entry(watch, &inode_data->watches, i_list) + ignore_helper(watch, IN_UNMOUNT); + put_inode_data(inode); + } + + spin_unlock(&inode_lock); +} +EXPORT_SYMBOL_GPL(inotify_super_block_umount); + +/* + * inotify_inode_is_dead - an inode has been deleted, cleanup any watches + */ +void inotify_inode_is_dead(struct inode *inode) +{ + struct inotify_watch *watch, *next; + struct inotify_inode_data *data; + + data = get_inode_data(inode); + if (!data) + return; + list_for_each_entry_safe(watch, next, &data->watches, i_list) + ignore_helper(watch, 0); + put_inode_data(inode); +} +EXPORT_SYMBOL_GPL(inotify_inode_is_dead); + +/* The driver interface is implemented below */ + +static unsigned int inotify_poll(struct file *file, poll_table *wait) +{ + struct inotify_device *dev; + + dev = file->private_data; + + poll_wait(file, &dev->wait, wait); + + if (inotify_dev_has_events(dev)) + return POLLIN | POLLRDNORM; + + return 0; +} + +static ssize_t inotify_read(struct file *file, char __user *buf, + size_t count, loff_t *pos) +{ + size_t event_size; + struct inotify_device *dev; + char __user *start; + DECLARE_WAITQUEUE(wait, current); + + start = buf; + dev = file->private_data; + + /* We only hand out full inotify events */ + event_size = sizeof(struct inotify_event); + if (count < event_size) + return -EINVAL; + + while (1) { + int has_events; + + spin_lock(&dev->lock); + has_events = inotify_dev_has_events(dev); + spin_unlock(&dev->lock); + if (has_events) + break; + + if (file->f_flags & O_NONBLOCK) + return -EAGAIN; + + if (signal_pending(current)) + return -ERESTARTSYS; + + add_wait_queue(&dev->wait, &wait); + set_current_state(TASK_INTERRUPTIBLE); + + schedule(); + + set_current_state(TASK_RUNNING); + remove_wait_queue(&dev->wait, &wait); + } + + while (count >= event_size) { + struct inotify_kernel_event *kevent; + + spin_lock(&dev->lock); + if (!inotify_dev_has_events(dev)) { + spin_unlock(&dev->lock); + break; + } + kevent = inotify_dev_get_event(dev); + spin_unlock(&dev->lock); + if (copy_to_user(buf, &kevent->event, event_size)) + return -EFAULT; + + spin_lock(&dev->lock); + inotify_dev_event_dequeue(dev); + spin_unlock(&dev->lock); + count -= event_size; + buf += event_size; + } + + return buf - start; +} + +static int inotify_open(struct inode *inode, struct file *file) +{ + struct inotify_device *dev; + struct user_struct *user; + int ret; + + user = get_uid(current->user); + + if (atomic_read(&user->inotify_devs) >= sysfs_attrib_max_user_devices) { + ret = -ENOSPC; + goto out_err; + } + + atomic_inc(¤t->user->inotify_devs); + + dev = kmalloc(sizeof(struct inotify_device), GFP_KERNEL); + if (!dev) { + ret = -ENOMEM; + goto out_err; + } + + idr_init(&dev->idr); + + INIT_LIST_HEAD(&dev->events); + INIT_LIST_HEAD(&dev->watches); + init_waitqueue_head(&dev->wait); + + dev->event_count = 0; + dev->max_events = sysfs_attrib_max_queued_events; + dev->user = user; + spin_lock_init(&dev->lock); + + file->private_data = dev; + + return 0; +out_err: + free_uid(current->user); + return ret; +} + +/* + * inotify_release_all_watches - destroy all watches on a given device + * + * FIXME: Do we want a lock here? + */ +static void inotify_release_all_watches(struct inotify_device *dev) +{ + struct inotify_watch *watch, *next; + + list_for_each_entry_safe(watch, next, &dev->watches, d_list) + ignore_helper(watch, 0); +} + +/* + * inotify_release_all_events - destroy all of the events on a given device + */ +static void inotify_release_all_events(struct inotify_device *dev) +{ + spin_lock(&dev->lock); + while (inotify_dev_has_events(dev)) + inotify_dev_event_dequeue(dev); + spin_unlock(&dev->lock); +} + +static int inotify_release(struct inode *inode, struct file *file) +{ + struct inotify_device *dev; + + dev = file->private_data; + + inotify_release_all_watches(dev); + inotify_release_all_events(dev); + + atomic_dec(&dev->user->inotify_devs); + free_uid(dev->user); + + kfree(dev); + + return 0; +} + +static int inotify_add_watch(struct inotify_device *dev, + struct inotify_watch_request *request) +{ + struct inode *inode; + struct inotify_watch *watch; + int ret; + + inode = find_inode((const char __user*) request->dirname); + if (IS_ERR(inode)) + return PTR_ERR(inode); + + spin_lock(&dev->lock); + + /* + * This handles the case of re-adding a directory we are already + * watching, we just update the mask and return 0 + */ + if (inotify_dev_is_watching_inode(dev, inode)) { + struct inotify_watch *owatch; /* the old watch */ + + owatch = inode_find_dev(inode, dev); + owatch->mask = request->mask; + inode_update_watch_mask(inode); + spin_unlock(&dev->lock); + iput(inode); + + return owatch->wd; + } + + spin_unlock(&dev->lock); + + watch = create_watch(dev, request->mask, inode); + if (!watch) { + iput(inode); + return -ENOSPC; + } + + spin_lock(&dev->lock); + + /* We can't add anymore watches to this device */ + if (inotify_dev_add_watch(dev, watch)) { + delete_watch(dev, watch); + spin_unlock(&dev->lock); + iput(inode); + return -EINVAL; + } + + ret = inode_add_watch(inode, watch); + if (ret < 0) { + list_del_init(&watch->d_list); + delete_watch(dev, watch); + spin_unlock(&dev->lock); + iput(inode); + return ret; + } + + spin_unlock(&dev->lock); + + return watch->wd; +} + +static int inotify_ignore(struct inotify_device *dev, s32 wd) +{ + struct inotify_watch *watch; + + /* + * FIXME: Silly to grab dev->lock here and then drop it, when + * ignore_helper() grabs it anyway a few lines down. + */ + spin_lock(&dev->lock); + watch = dev_find_wd(dev, wd); + spin_unlock(&dev->lock); + if (!watch) + return -EINVAL; + ignore_helper(watch, 0); + + return 0; +} + +/* + * inotify_ioctl() - our device file's ioctl method + * + * The VFS serializes all of our calls via the BKL and we rely on that. We + * could, alternatively, grab dev->lock. Right now lower levels grab that + * where needed. + */ +static int inotify_ioctl(struct inode *ip, struct file *fp, + unsigned int cmd, unsigned long arg) +{ + struct inotify_device *dev; + struct inotify_watch_request request; + void __user *p; + int bytes; + s32 wd; + + dev = fp->private_data; + p = (void __user *) arg; + + switch (cmd) { + case INOTIFY_WATCH: + if (copy_from_user(&request, p, sizeof (request))) + return -EFAULT; + return inotify_add_watch(dev, &request); + case INOTIFY_IGNORE: + if (copy_from_user(&wd, p, sizeof (wd))) + return -EFAULT; + return inotify_ignore(dev, wd); + case FIONREAD: + bytes = dev->event_count * sizeof(struct inotify_event); + return put_user(bytes, (int __user *) p); + default: + return -ENOTTY; + } +} + +static struct file_operations inotify_fops = { + .owner = THIS_MODULE, + .poll = inotify_poll, + .read = inotify_read, + .open = inotify_open, + .release = inotify_release, + .ioctl = inotify_ioctl, +}; + +struct miscdevice inotify_device = { + .minor = MISC_DYNAMIC_MINOR, + .name = "inotify", + .fops = &inotify_fops, +}; + +static int __init inotify_init(void) +{ + struct class_device *class; + int ret; + + ret = misc_register(&inotify_device); + if (ret) + return ret; + + sysfs_attrib_max_queued_events = 512; + sysfs_attrib_max_user_devices = 64; + sysfs_attrib_max_user_watches = 16384; + + class = inotify_device.class; + class_device_create_file(class, &class_device_attr_max_queued_events); + class_device_create_file(class, &class_device_attr_max_user_devices); + class_device_create_file(class, &class_device_attr_max_user_watches); + + atomic_set(&inotify_cookie, 0); + + watch_cachep = kmem_cache_create("inotify_watch_cache", + sizeof(struct inotify_watch), 0, SLAB_PANIC, + NULL, NULL); + + event_cachep = kmem_cache_create("inotify_event_cache", + sizeof(struct inotify_kernel_event), 0, + SLAB_PANIC, NULL, NULL); + + inode_data_cachep = kmem_cache_create("inotify_inode_data_cache", + sizeof(struct inotify_inode_data), 0, SLAB_PANIC, + NULL, NULL); + + printk(KERN_INFO "inotify device minor=%d\n", inotify_device.minor); + + return 0; +} + +module_init(inotify_init); diff -puN drivers/char/Kconfig~inotify drivers/char/Kconfig --- 25/drivers/char/Kconfig~inotify 2005-01-13 23:04:31.478047600 -0800 +++ 25-akpm/drivers/char/Kconfig 2005-01-13 23:04:31.505043496 -0800 @@ -62,6 +62,19 @@ config HW_CONSOLE depends on VT && !S390 && !USERMODE default y +config INOTIFY + bool "Inotify file change notification support" + default y + ---help--- + Say Y here to enable inotify support and the /dev/inotify character + device. Inotify is a file change notification system and a + replacement for dnotify. Inotify fixes numerous shortcomings in + dnotify and introduces several new features. It allows monitoring + of both files and directories via a single open fd. Multiple file + events are supported. + + If unsure, say Y. + config SERIAL_NONSTANDARD bool "Non-standard serial port support" ---help--- diff -puN drivers/char/Makefile~inotify drivers/char/Makefile --- 25/drivers/char/Makefile~inotify 2005-01-13 23:04:31.479047448 -0800 +++ 25-akpm/drivers/char/Makefile 2005-01-13 23:04:31.505043496 -0800 @@ -9,6 +9,8 @@ FONTMAPFILE = cp437.uni obj-y += mem.o random.o tty_io.o n_tty.o tty_ioctl.o + +obj-$(CONFIG_INOTIFY) += inotify.o obj-$(CONFIG_LEGACY_PTYS) += pty.o obj-$(CONFIG_UNIX98_PTYS) += pty.o obj-y += misc.o diff -puN fs/attr.c~inotify fs/attr.c --- 25/fs/attr.c~inotify 2005-01-13 23:04:31.481047144 -0800 +++ 25-akpm/fs/attr.c 2005-01-13 23:04:31.506043344 -0800 @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -107,29 +108,51 @@ int inode_setattr(struct inode * inode, out: return error; } - EXPORT_SYMBOL(inode_setattr); -int setattr_mask(unsigned int ia_valid) +void setattr_mask (unsigned int ia_valid, int *dn_mask, u32 *in_mask) { - unsigned long dn_mask = 0; + int dnmask; + u32 inmask; - if (ia_valid & ATTR_UID) - dn_mask |= DN_ATTRIB; - if (ia_valid & ATTR_GID) - dn_mask |= DN_ATTRIB; - if (ia_valid & ATTR_SIZE) - dn_mask |= DN_MODIFY; - /* both times implies a utime(s) call */ - if ((ia_valid & (ATTR_ATIME|ATTR_MTIME)) == (ATTR_ATIME|ATTR_MTIME)) - dn_mask |= DN_ATTRIB; - else if (ia_valid & ATTR_ATIME) - dn_mask |= DN_ACCESS; - else if (ia_valid & ATTR_MTIME) - dn_mask |= DN_MODIFY; - if (ia_valid & ATTR_MODE) - dn_mask |= DN_ATTRIB; - return dn_mask; + inmask = 0; + dnmask = 0; + + if (!dn_mask || !in_mask) { + return; + } + if (ia_valid & ATTR_UID) { + inmask |= IN_ATTRIB; + dnmask |= DN_ATTRIB; + } + if (ia_valid & ATTR_GID) { + inmask |= IN_ATTRIB; + dnmask |= DN_ATTRIB; + } + if (ia_valid & ATTR_SIZE) { + inmask |= IN_MODIFY; + dnmask |= DN_MODIFY; + } + /* both times implies a utime(s) call */ + if ((ia_valid & (ATTR_ATIME|ATTR_MTIME)) == (ATTR_ATIME|ATTR_MTIME)) { + inmask |= IN_ATTRIB; + dnmask |= DN_ATTRIB; + } + else if (ia_valid & ATTR_ATIME) { + inmask |= IN_ACCESS; + dnmask |= DN_ACCESS; + } + else if (ia_valid & ATTR_MTIME) { + inmask |= IN_MODIFY; + dnmask |= DN_MODIFY; + } + if (ia_valid & ATTR_MODE) { + inmask |= IN_ATTRIB; + dnmask |= DN_ATTRIB; + } + + *in_mask = inmask; + *dn_mask = dnmask; } int notify_change(struct dentry * dentry, struct iattr * attr) @@ -195,9 +218,19 @@ int notify_change(struct dentry * dentry up_write(&dentry->d_inode->i_alloc_sem); if (!error) { - unsigned long dn_mask = setattr_mask(ia_valid); + int dn_mask; + u32 in_mask; + + setattr_mask (ia_valid, &dn_mask, &in_mask); + if (dn_mask) dnotify_parent(dentry, dn_mask); + if (in_mask) { + inotify_inode_queue_event(dentry->d_inode, in_mask, 0, + NULL); + inotify_dentry_parent_queue_event(dentry, in_mask, 0, + dentry->d_name.name); + } } return error; } diff -puN fs/file_table.c~inotify fs/file_table.c --- 25/fs/file_table.c~inotify 2005-01-13 23:04:31.483046840 -0800 +++ 25-akpm/fs/file_table.c 2005-01-13 23:04:31.507043192 -0800 @@ -16,6 +16,7 @@ #include #include #include +#include /* sysctl tunables... */ struct files_stat_struct files_stat = { @@ -120,6 +121,12 @@ void fastcall __fput(struct file *file) struct dentry *dentry = file->f_dentry; struct vfsmount *mnt = file->f_vfsmnt; struct inode *inode = dentry->d_inode; + u32 mask; + + + mask = (file->f_mode & FMODE_WRITE) ? IN_CLOSE_WRITE : IN_CLOSE_NOWRITE; + inotify_dentry_parent_queue_event(dentry, mask, 0, dentry->d_name.name); + inotify_inode_queue_event(inode, mask, 0, NULL); might_sleep(); /* diff -puN fs/inode.c~inotify fs/inode.c --- 25/fs/inode.c~inotify 2005-01-13 23:04:31.484046688 -0800 +++ 25-akpm/fs/inode.c 2005-01-13 23:04:31.508043040 -0800 @@ -130,6 +130,9 @@ static struct inode *alloc_inode(struct #ifdef CONFIG_QUOTA memset(&inode->i_dquot, 0, sizeof(inode->i_dquot)); #endif +#ifdef CONFIG_INOTIFY + inode->inotify_data = NULL; +#endif inode->i_pipe = NULL; inode->i_bdev = NULL; inode->i_cdev = NULL; diff -puN fs/namei.c~inotify fs/namei.c --- 25/fs/namei.c~inotify 2005-01-13 23:04:31.486046384 -0800 +++ 25-akpm/fs/namei.c 2005-01-13 23:04:31.510042736 -0800 @@ -22,6 +22,7 @@ #include #include #include +#include #include #include #include @@ -1253,6 +1254,8 @@ int vfs_create(struct inode *dir, struct error = dir->i_op->create(dir, dentry, mode, nd); if (!error) { inode_dir_notify(dir, DN_CREATE); + inotify_inode_queue_event(dir, IN_CREATE_FILE, + 0, dentry->d_name.name); security_inode_post_create(dir, dentry, mode); } return error; @@ -1558,6 +1561,8 @@ int vfs_mknod(struct inode *dir, struct error = dir->i_op->mknod(dir, dentry, mode, dev); if (!error) { inode_dir_notify(dir, DN_CREATE); + inotify_inode_queue_event(dir, IN_CREATE_FILE, 0, + dentry->d_name.name); security_inode_post_mknod(dir, dentry, mode, dev); } return error; @@ -1631,6 +1636,8 @@ int vfs_mkdir(struct inode *dir, struct error = dir->i_op->mkdir(dir, dentry, mode); if (!error) { inode_dir_notify(dir, DN_CREATE); + inotify_inode_queue_event(dir, IN_CREATE_SUBDIR, 0, + dentry->d_name.name); security_inode_post_mkdir(dir,dentry, mode); } return error; @@ -1726,6 +1733,11 @@ int vfs_rmdir(struct inode *dir, struct up(&dentry->d_inode->i_sem); if (!error) { inode_dir_notify(dir, DN_DELETE); + inotify_inode_queue_event(dir, IN_DELETE_SUBDIR, 0, + dentry->d_name.name); + inotify_inode_queue_event(dentry->d_inode, IN_DELETE_SELF, 0, + NULL); + inotify_inode_is_dead (dentry->d_inode); d_delete(dentry); } dput(dentry); @@ -1798,8 +1810,13 @@ int vfs_unlink(struct inode *dir, struct /* We don't d_delete() NFS sillyrenamed files--they still exist. */ if (!error && !(dentry->d_flags & DCACHE_NFSFS_RENAMED)) { - d_delete(dentry); inode_dir_notify(dir, DN_DELETE); + inotify_inode_queue_event(dir, IN_DELETE_FILE, 0, + dentry->d_name.name); + inotify_inode_queue_event(dentry->d_inode, IN_DELETE_SELF, 0, + NULL); + inotify_inode_is_dead (dentry->d_inode); + d_delete(dentry); } return error; } @@ -1875,6 +1892,8 @@ int vfs_symlink(struct inode *dir, struc error = dir->i_op->symlink(dir, dentry, oldname); if (!error) { inode_dir_notify(dir, DN_CREATE); + inotify_inode_queue_event(dir, IN_CREATE_FILE, 0, + dentry->d_name.name); security_inode_post_symlink(dir, dentry, oldname); } return error; @@ -1948,6 +1967,8 @@ int vfs_link(struct dentry *old_dentry, up(&old_dentry->d_inode->i_sem); if (!error) { inode_dir_notify(dir, DN_CREATE); + inotify_inode_queue_event(dir, IN_CREATE_FILE, 0, + new_dentry->d_name.name); security_inode_post_link(old_dentry, dir, new_dentry); } return error; @@ -2111,6 +2132,8 @@ int vfs_rename(struct inode *old_dir, st { int error; int is_dir = S_ISDIR(old_dentry->d_inode->i_mode); + char *old_name; + u32 cookie; if (old_dentry->d_inode == new_dentry->d_inode) return 0; @@ -2132,6 +2155,8 @@ int vfs_rename(struct inode *old_dir, st DQUOT_INIT(old_dir); DQUOT_INIT(new_dir); + old_name = inotify_oldname_init(old_dentry); + if (is_dir) error = vfs_rename_dir(old_dir,old_dentry,new_dir,new_dentry); else @@ -2143,7 +2168,15 @@ int vfs_rename(struct inode *old_dir, st inode_dir_notify(old_dir, DN_DELETE); inode_dir_notify(new_dir, DN_CREATE); } + + cookie = inotify_get_cookie(); + + inotify_inode_queue_event(old_dir, IN_MOVED_FROM, cookie, old_name); + inotify_inode_queue_event(new_dir, IN_MOVED_TO, cookie, + new_dentry->d_name.name); } + inotify_oldname_free(old_name); + return error; } diff -puN fs/open.c~inotify fs/open.c --- 25/fs/open.c~inotify 2005-01-13 23:04:31.487046232 -0800 +++ 25-akpm/fs/open.c 2005-01-13 23:04:52.951783096 -0800 @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -952,6 +953,10 @@ asmlinkage long sys_open(const char __us ltt_ev_file_system(LTT_EV_FILE_SYSTEM_OPEN, fd, f->f_dentry->d_name.len, f->f_dentry->d_name.name); + inotify_inode_queue_event(f->f_dentry->d_inode, + IN_OPEN, 0, NULL); + inotify_dentry_parent_queue_event(f->f_dentry, IN_OPEN, + 0, f->f_dentry->d_name.name); fd_install(fd, f); } out: diff -puN fs/read_write.c~inotify fs/read_write.c --- 25/fs/read_write.c~inotify 2005-01-13 23:04:31.489045928 -0800 +++ 25-akpm/fs/read_write.c 2005-01-13 23:04:31.513042280 -0800 @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -223,7 +224,12 @@ ssize_t vfs_read(struct file *file, char else ret = do_sync_read(file, buf, count, pos); if (ret > 0) { - dnotify_parent(file->f_dentry, DN_ACCESS); + struct dentry *dentry = file->f_dentry; + dnotify_parent(dentry, DN_ACCESS); + inotify_dentry_parent_queue_event(dentry, + IN_ACCESS, 0, dentry->d_name.name); + inotify_inode_queue_event(inode, IN_ACCESS, 0, + NULL); current->rchar += ret; } current->syscr++; @@ -270,7 +276,12 @@ ssize_t vfs_write(struct file *file, con else ret = do_sync_write(file, buf, count, pos); if (ret > 0) { - dnotify_parent(file->f_dentry, DN_MODIFY); + struct dentry *dentry = file->f_dentry; + dnotify_parent(dentry, DN_MODIFY); + inotify_dentry_parent_queue_event(dentry, + IN_MODIFY, 0, dentry->d_name.name); + inotify_inode_queue_event(inode, IN_MODIFY, 0, + NULL); current->wchar += ret; } current->syscw++; @@ -514,9 +525,15 @@ static ssize_t do_readv_writev(int type, out: if (iov != iovstack) kfree(iov); - if ((ret + (type == READ)) > 0) - dnotify_parent(file->f_dentry, - (type == READ) ? DN_ACCESS : DN_MODIFY); + if ((ret + (type == READ)) > 0) { + struct dentry *dentry = file->f_dentry; + dnotify_parent(dentry, (type == READ) ? DN_ACCESS : DN_MODIFY); + inotify_dentry_parent_queue_event(dentry, + (type == READ) ? IN_ACCESS : IN_MODIFY, 0, + dentry->d_name.name); + inotify_inode_queue_event (dentry->d_inode, + (type == READ) ? IN_ACCESS : IN_MODIFY, 0, NULL); + } return ret; } diff -puN fs/super.c~inotify fs/super.c --- 25/fs/super.c~inotify 2005-01-13 23:04:31.490045776 -0800 +++ 25-akpm/fs/super.c 2005-01-13 23:04:31.514042128 -0800 @@ -38,6 +38,7 @@ #include #include #include +#include void get_filesystem(struct file_system_type *fs); @@ -229,6 +230,7 @@ void generic_shutdown_super(struct super if (root) { sb->s_root = NULL; + inotify_super_block_umount(sb); shrink_dcache_parent(root); shrink_dcache_anon(&sb->s_anon); dput(root); diff -puN include/linux/fs.h~inotify include/linux/fs.h --- 25/include/linux/fs.h~inotify 2005-01-13 23:04:31.492045472 -0800 +++ 25-akpm/include/linux/fs.h 2005-01-13 23:04:31.516041824 -0800 @@ -27,6 +27,7 @@ struct poll_table_struct; struct kstatfs; struct vm_area_struct; struct vfsmount; +struct inotify_inode_data; /* * It's silly to have NR_OPEN bigger than NR_FILE, but you can change @@ -470,6 +471,10 @@ struct inode { struct dnotify_struct *i_dnotify; /* for directory notifications */ #endif +#ifdef CONFIG_INOTIFY + struct inotify_inode_data *inotify_data; +#endif + unsigned long i_state; unsigned long dirtied_when; /* jiffies of first dirtying */ @@ -1360,7 +1365,7 @@ extern void emergency_remount(void); extern int do_remount_sb(struct super_block *sb, int flags, void *data, int force); extern sector_t bmap(struct inode *, sector_t); -extern int setattr_mask(unsigned int); +extern void setattr_mask(unsigned int, int *, u32 *); extern int notify_change(struct dentry *, struct iattr *); extern int permission(struct inode *, int, struct nameidata *); extern int generic_permission(struct inode *, int, diff -puN /dev/null include/linux/inotify.h --- /dev/null 2003-09-15 06:40:47.000000000 -0700 +++ 25-akpm/include/linux/inotify.h 2005-01-13 23:04:31.517041672 -0800 @@ -0,0 +1,155 @@ +/* + * Inode based directory notification for Linux + * + * Copyright (C) 2004 John McCutchan + */ + +#ifndef _LINUX_INOTIFY_H +#define _LINUX_INOTIFY_H + +#include +#include + +/* this size could limit things, since technically we could need PATH_MAX */ +#define INOTIFY_FILENAME_MAX 256 + +/* + * struct inotify_event - structure read from the inotify device for each event + * + * When you are watching a directory, you will receive the filename for events + * such as IN_CREATE, IN_DELETE, IN_OPEN, IN_CLOSE, ... + * + * Note: When reading from the device you must provide a buffer that is a + * multiple of sizeof(struct inotify_event) + */ +struct inotify_event { + __s32 wd; + __u32 mask; + __u32 cookie; + char filename[INOTIFY_FILENAME_MAX]; +}; + +/* + * struct inotify_watch_request - represents a watch request + * + * Pass to the inotify device via the INOTIFY_WATCH ioctl + */ +struct inotify_watch_request { + char *dirname; /* directory name */ + __u32 mask; /* event mask */ +}; + +/* the following are legal, implemented events */ +#define IN_ACCESS 0x00000001 /* File was accessed */ +#define IN_MODIFY 0x00000002 /* File was modified */ +#define IN_ATTRIB 0x00000004 /* File changed attributes */ +#define IN_CLOSE_WRITE 0x00000008 /* Writtable file was closed */ +#define IN_CLOSE_NOWRITE 0x00000010 /* Unwrittable file closed */ +#define IN_OPEN 0x00000020 /* File was opened */ +#define IN_MOVED_FROM 0x00000040 /* File was moved from X */ +#define IN_MOVED_TO 0x00000080 /* File was moved to Y */ +#define IN_DELETE_SUBDIR 0x00000100 /* Subdir was deleted */ +#define IN_DELETE_FILE 0x00000200 /* Subfile was deleted */ +#define IN_CREATE_SUBDIR 0x00000400 /* Subdir was created */ +#define IN_CREATE_FILE 0x00000800 /* Subfile was created */ +#define IN_DELETE_SELF 0x00001000 /* Self was deleted */ +#define IN_UNMOUNT 0x00002000 /* Backing fs was unmounted */ +#define IN_Q_OVERFLOW 0x00004000 /* Event queued overflowed */ +#define IN_IGNORED 0x00008000 /* File was ignored */ + +/* special flags */ +#define IN_ALL_EVENTS 0xffffffff /* All the events */ +#define IN_CLOSE (IN_CLOSE_WRITE | IN_CLOSE_NOWRITE) + +#define INOTIFY_IOCTL_MAGIC 'Q' +#define INOTIFY_IOCTL_MAXNR 2 + +#define INOTIFY_WATCH _IOR(INOTIFY_IOCTL_MAGIC, 1, struct inotify_watch_request) +#define INOTIFY_IGNORE _IOR(INOTIFY_IOCTL_MAGIC, 2, int) + +#ifdef __KERNEL__ + +#include +#include +#include + +struct inotify_inode_data { + struct list_head watches; + __u32 watch_mask; + spinlock_t lock; + atomic_t count; +}; + +#ifdef CONFIG_INOTIFY + +extern void inotify_inode_queue_event(struct inode *, __u32, __u32, + const char *); +extern void inotify_dentry_parent_queue_event(struct dentry *, __u32, __u32, + const char *); +extern void inotify_super_block_umount(struct super_block *); +extern void inotify_inode_is_dead(struct inode *); +extern __u32 inotify_get_cookie(void); +extern __u32 setattr_mask_inotify(unsigned int); + +/* this could be kstrdup if only we could add that to lib/string.c */ +static inline char * inotify_oldname_init(struct dentry *old_dentry) +{ + char *old_name; + + old_name = kmalloc(strlen(old_dentry->d_name.name) + 1, GFP_KERNEL); + if (old_name) + strcpy(old_name, old_dentry->d_name.name); + return old_name; +} + +static inline void inotify_oldname_free(const char *old_name) +{ + kfree(old_name); +} + +#else + +static inline void inotify_inode_queue_event(struct inode *inode, + __u32 mask, __u32 cookie, + const char *filename) +{ +} + +static inline void inotify_dentry_parent_queue_event(struct dentry *dentry, + __u32 mask, __u32 cookie, + const char *filename) +{ +} + +static inline void inotify_super_block_umount(struct super_block *sb) +{ +} + +static inline void inotify_inode_is_dead(struct inode *inode) +{ +} + +static inline char * inotify_oldname_init(struct dentry *old_dentry) +{ + return NULL; +} + +static inline __u32 inotify_get_cookie(void) +{ + return 0; +} + +static inline void inotify_oldname_free(const char *old_name) +{ +} + +static inline int setattr_mask_inotify(unsigned int ia_mask) +{ + return 0; +} + +#endif /* CONFIG_INOTIFY */ + +#endif /* __KERNEL __ */ + +#endif /* _LINUX_INOTIFY_H */ diff -puN include/linux/miscdevice.h~inotify include/linux/miscdevice.h --- 25/include/linux/miscdevice.h~inotify 2005-01-13 23:04:31.493045320 -0800 +++ 25-akpm/include/linux/miscdevice.h 2005-01-13 23:04:31.518041520 -0800 @@ -2,6 +2,7 @@ #define _LINUX_MISCDEVICE_H #include #include +#include #define PSMOUSE_MINOR 1 #define MS_BUSMOUSE_MINOR 2 diff -puN include/linux/sched.h~inotify include/linux/sched.h --- 25/include/linux/sched.h~inotify 2005-01-13 23:04:31.495045016 -0800 +++ 25-akpm/include/linux/sched.h 2005-01-13 23:04:31.519041368 -0800 @@ -368,6 +368,8 @@ struct user_struct { atomic_t processes; /* How many processes does this user have? */ atomic_t files; /* How many open files does this user have? */ atomic_t sigpending; /* How many pending signals does this user have? */ + atomic_t inotify_watches; /* How many inotify watches does this user have? */ + atomic_t inotify_devs; /* How many inotify devs does this user have opened? */ /* protected by mq_lock */ unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */ unsigned long locked_shm; /* How many pages of mlocked shm ? */ diff -puN kernel/user.c~inotify kernel/user.c --- 25/kernel/user.c~inotify 2005-01-13 23:04:31.496044864 -0800 +++ 25-akpm/kernel/user.c 2005-01-13 23:04:31.519041368 -0800 @@ -119,6 +119,8 @@ struct user_struct * alloc_uid(uid_t uid atomic_set(&new->processes, 0); atomic_set(&new->files, 0); atomic_set(&new->sigpending, 0); + atomic_set(&new->inotify_watches, 0); + atomic_set(&new->inotify_devs, 0); new->mq_bytes = 0; new->locked_shm = 0; _