diff options
Diffstat (limited to 'fs/notify/inotify')
| -rw-r--r-- | fs/notify/inotify/Kconfig | 15 | ||||
| -rw-r--r-- | fs/notify/inotify/Makefile | 1 | ||||
| -rw-r--r-- | fs/notify/inotify/inotify.c | 873 | ||||
| -rw-r--r-- | fs/notify/inotify/inotify.h | 7 | ||||
| -rw-r--r-- | fs/notify/inotify/inotify_fsnotify.c | 151 | ||||
| -rw-r--r-- | fs/notify/inotify/inotify_user.c | 369 |
6 files changed, 338 insertions, 1078 deletions
diff --git a/fs/notify/inotify/Kconfig b/fs/notify/inotify/Kconfig index b3a159b..b981fc0 100644 --- a/fs/notify/inotify/Kconfig +++ b/fs/notify/inotify/Kconfig @@ -1,18 +1,3 @@ -config INOTIFY - bool "Inotify file change notification support" - default n - ---help--- - Say Y here to enable legacy in kernel inotify support. Inotify is a - file change notification system. It is a replacement for dnotify. - This option only provides the legacy inotify in kernel API. There - are no in tree kernel users of this interface since it is deprecated. - You only need this if you are loading an out of tree kernel module - that uses inotify. - - For more information, see <file:Documentation/filesystems/inotify.txt> - - If unsure, say N. - config INOTIFY_USER bool "Inotify support for userspace" select ANON_INODES diff --git a/fs/notify/inotify/Makefile b/fs/notify/inotify/Makefile index 9438281..a380dab 100644 --- a/fs/notify/inotify/Makefile +++ b/fs/notify/inotify/Makefile @@ -1,2 +1 @@ -obj-$(CONFIG_INOTIFY) += inotify.o obj-$(CONFIG_INOTIFY_USER) += inotify_fsnotify.o inotify_user.o diff --git a/fs/notify/inotify/inotify.c b/fs/notify/inotify/inotify.c deleted file mode 100644 index 27b75eb..0000000 --- a/fs/notify/inotify/inotify.c +++ /dev/null @@ -1,873 +0,0 @@ -/* - * fs/inotify.c - inode-based file event notifications - * - * Authors: - * John McCutchan <ttb@tentacle.dhs.org> - * Robert Love <rml@novell.com> - * - * Kernel API added by: Amy Griffis <amy.griffis@hp.com> - * - * Copyright (C) 2005 John McCutchan - * Copyright 2006 Hewlett-Packard Development Company, L.P. - * - * 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/module.h> -#include <linux/kernel.h> -#include <linux/spinlock.h> -#include <linux/idr.h> -#include <linux/slab.h> -#include <linux/fs.h> -#include <linux/sched.h> -#include <linux/init.h> -#include <linux/list.h> -#include <linux/writeback.h> -#include <linux/inotify.h> -#include <linux/fsnotify_backend.h> - -static atomic_t inotify_cookie; - -/* - * Lock ordering: - * - * dentry->d_lock (used to keep d_move() away from dentry->d_parent) - * iprune_mutex (synchronize shrink_icache_memory()) - * inode_lock (protects the super_block->s_inodes list) - * inode->inotify_mutex (protects inode->inotify_watches and watches->i_list) - * inotify_handle->mutex (protects inotify_handle and watches->h_list) - * - * The inode->inotify_mutex and inotify_handle->mutex and held during execution - * of a caller's event handler. Thus, the caller must not hold any locks - * taken in their event handler while calling any of the published inotify - * interfaces. - */ - -/* - * Lifetimes of the three main data structures--inotify_handle, inode, and - * inotify_watch--are managed by reference count. - * - * inotify_handle: Lifetime is from inotify_init() to inotify_destroy(). - * Additional references can bump the count via get_inotify_handle() and drop - * the count via put_inotify_handle(). - * - * inotify_watch: for inotify's purposes, lifetime is from inotify_add_watch() - * to remove_watch_no_event(). Additional references can bump the count via - * get_inotify_watch() and drop the count via put_inotify_watch(). The caller - * is reponsible for the final put after receiving IN_IGNORED, or when using - * IN_ONESHOT after receiving the first event. Inotify does the final put if - * inotify_destroy() is called. - * - * inode: Pinned so long as the inode is associated with a watch, from - * inotify_add_watch() to the final put_inotify_watch(). - */ - -/* - * struct inotify_handle - represents an inotify instance - * - * This structure is protected by the mutex 'mutex'. - */ -struct inotify_handle { - struct idr idr; /* idr mapping wd -> watch */ - struct mutex mutex; /* protects this bad boy */ - struct list_head watches; /* list of watches */ - atomic_t count; /* reference count */ - u32 last_wd; /* the last wd allocated */ - const struct inotify_operations *in_ops; /* inotify caller operations */ -}; - -static inline void get_inotify_handle(struct inotify_handle *ih) -{ - atomic_inc(&ih->count); -} - -static inline void put_inotify_handle(struct inotify_handle *ih) -{ - if (atomic_dec_and_test(&ih->count)) { - idr_destroy(&ih->idr); - kfree(ih); - } -} - -/** - * get_inotify_watch - grab a reference to an inotify_watch - * @watch: watch to grab - */ -void get_inotify_watch(struct inotify_watch *watch) -{ - atomic_inc(&watch->count); -} -EXPORT_SYMBOL_GPL(get_inotify_watch); - -int pin_inotify_watch(struct inotify_watch *watch) -{ - struct super_block *sb = watch->inode->i_sb; - if (atomic_inc_not_zero(&sb->s_active)) { - atomic_inc(&watch->count); - return 1; - } - return 0; -} - -/** - * put_inotify_watch - decrements the ref count on a given watch. cleans up - * watch references if the count reaches zero. inotify_watch is freed by - * inotify callers via the destroy_watch() op. - * @watch: watch to release - */ -void put_inotify_watch(struct inotify_watch *watch) -{ - if (atomic_dec_and_test(&watch->count)) { - struct inotify_handle *ih = watch->ih; - - iput(watch->inode); - ih->in_ops->destroy_watch(watch); - put_inotify_handle(ih); - } -} -EXPORT_SYMBOL_GPL(put_inotify_watch); - -void unpin_inotify_watch(struct inotify_watch *watch) -{ - struct super_block *sb = watch->inode->i_sb; - put_inotify_watch(watch); - deactivate_super(sb); -} - -/* - * inotify_handle_get_wd - returns the next WD for use by the given handle - * - * Callers must hold ih->mutex. This function can sleep. - */ -static int inotify_handle_get_wd(struct inotify_handle *ih, - struct inotify_watch *watch) -{ - int ret; - - do { - if (unlikely(!idr_pre_get(&ih->idr, GFP_NOFS))) - return -ENOSPC; - ret = idr_get_new_above(&ih->idr, watch, ih->last_wd+1, &watch->wd); - } while (ret == -EAGAIN); - - if (likely(!ret)) - ih->last_wd = watch->wd; - - return ret; -} - -/* - * inotify_inode_watched - returns nonzero if there are watches on this inode - * and zero otherwise. We call this lockless, we do not care if we race. - */ -static inline int inotify_inode_watched(struct inode *inode) -{ - return !list_empty(&inode->inotify_watches); -} - -/* - * Get child dentry flag into synch with parent inode. - * Flag should always be clear for negative dentrys. - */ -static void set_dentry_child_flags(struct inode *inode, int watched) -{ - struct dentry *alias; - - spin_lock(&dcache_lock); - list_for_each_entry(alias, &inode->i_dentry, d_alias) { - struct dentry *child; - - list_for_each_entry(child, &alias->d_subdirs, d_u.d_child) { - if (!child->d_inode) - continue; - - spin_lock(&child->d_lock); - if (watched) - child->d_flags |= DCACHE_INOTIFY_PARENT_WATCHED; - else - child->d_flags &=~DCACHE_INOTIFY_PARENT_WATCHED; - spin_unlock(&child->d_lock); - } - } - spin_unlock(&dcache_lock); -} - -/* - * inotify_find_handle - find the watch associated with the given inode and - * handle - * - * Callers must hold inode->inotify_mutex. - */ -static struct inotify_watch *inode_find_handle(struct inode *inode, - struct inotify_handle *ih) -{ - struct inotify_watch *watch; - - list_for_each_entry(watch, &inode->inotify_watches, i_list) { - if (watch->ih == ih) - return watch; - } - - return NULL; -} - -/* - * remove_watch_no_event - remove watch without the IN_IGNORED event. - * - * Callers must hold both inode->inotify_mutex and ih->mutex. - */ -static void remove_watch_no_event(struct inotify_watch *watch, - struct inotify_handle *ih) -{ - list_del(&watch->i_list); - list_del(&watch->h_list); - - if (!inotify_inode_watched(watch->inode)) - set_dentry_child_flags(watch->inode, 0); - - idr_remove(&ih->idr, watch->wd); -} - -/** - * inotify_remove_watch_locked - Remove a watch from both the handle and the - * inode. Sends the IN_IGNORED event signifying that the inode is no longer - * watched. May be invoked from a caller's event handler. - * @ih: inotify handle associated with watch - * @watch: watch to remove - * - * Callers must hold both inode->inotify_mutex and ih->mutex. - */ -void inotify_remove_watch_locked(struct inotify_handle *ih, - struct inotify_watch *watch) -{ - remove_watch_no_event(watch, ih); - ih->in_ops->handle_event(watch, watch->wd, IN_IGNORED, 0, NULL, NULL); -} -EXPORT_SYMBOL_GPL(inotify_remove_watch_locked); - -/* Kernel API for producing events */ - -/* - * inotify_d_instantiate - instantiate dcache entry for inode - */ -void inotify_d_instantiate(struct dentry *entry, struct inode *inode) -{ - struct dentry *parent; - - if (!inode) - return; - - spin_lock(&entry->d_lock); - parent = entry->d_parent; - if (parent->d_inode && inotify_inode_watched(parent->d_inode)) - entry->d_flags |= DCACHE_INOTIFY_PARENT_WATCHED; - spin_unlock(&entry->d_lock); -} - -/* - * inotify_d_move - dcache entry has been moved - */ -void inotify_d_move(struct dentry *entry) -{ - struct dentry *parent; - - parent = entry->d_parent; - if (inotify_inode_watched(parent->d_inode)) - entry->d_flags |= DCACHE_INOTIFY_PARENT_WATCHED; - else - entry->d_flags &= ~DCACHE_INOTIFY_PARENT_WATCHED; -} - -/** - * inotify_inode_queue_event - queue an event to all watches on this inode - * @inode: inode event is originating from - * @mask: event mask describing this event - * @cookie: cookie for synchronization, or zero - * @name: filename, if any - * @n_inode: inode associated with name - */ -void inotify_inode_queue_event(struct inode *inode, u32 mask, u32 cookie, - const char *name, struct inode *n_inode) -{ - struct inotify_watch *watch, *next; - - if (!inotify_inode_watched(inode)) - return; - - mutex_lock(&inode->inotify_mutex); - list_for_each_entry_safe(watch, next, &inode->inotify_watches, i_list) { - u32 watch_mask = watch->mask; - if (watch_mask & mask) { - struct inotify_handle *ih= watch->ih; - mutex_lock(&ih->mutex); - if (watch_mask & IN_ONESHOT) - remove_watch_no_event(watch, ih); - ih->in_ops->handle_event(watch, watch->wd, mask, cookie, - name, n_inode); - mutex_unlock(&ih->mutex); - } - } - mutex_unlock(&inode->inotify_mutex); -} -EXPORT_SYMBOL_GPL(inotify_inode_queue_event); - -/** - * inotify_dentry_parent_queue_event - queue an event to a dentry's parent - * @dentry: the dentry in question, we queue against this dentry's parent - * @mask: event mask describing this event - * @cookie: cookie for synchronization, or zero - * @name: filename, if any - */ -void inotify_dentry_parent_queue_event(struct dentry *dentry, u32 mask, - u32 cookie, const char *name) -{ - struct dentry *parent; - struct inode *inode; - - if (!(dentry->d_flags & DCACHE_INOTIFY_PARENT_WATCHED)) - return; - - spin_lock(&dentry->d_lock); - parent = dentry->d_parent; - inode = parent->d_inode; - - if (inotify_inode_watched(inode)) { - dget(parent); - spin_unlock(&dentry->d_lock); - inotify_inode_queue_event(inode, mask, cookie, name, - dentry->d_inode); - dput(parent); - } else - spin_unlock(&dentry->d_lock); -} -EXPORT_SYMBOL_GPL(inotify_dentry_parent_queue_event); - -/** - * inotify_get_cookie - return a unique cookie for use in synchronizing events. - */ -u32 inotify_get_cookie(void) -{ - return atomic_inc_return(&inotify_cookie); -} -EXPORT_SYMBOL_GPL(inotify_get_cookie); - -/** - * inotify_unmount_inodes - an sb is unmounting. handle any watched inodes. - * @list: list of inodes being unmounted (sb->s_inodes) - * - * Called with inode_lock held, protecting the unmounting super block's list - * of inodes, and with iprune_mutex held, keeping shrink_icache_memory() at bay. - * We temporarily drop inode_lock, however, and CAN block. - */ -void inotify_unmount_inodes(struct list_head *list) -{ - struct inode *inode, *next_i, *need_iput = NULL; - - list_for_each_entry_safe(inode, next_i, list, i_sb_list) { - struct inotify_watch *watch, *next_w; - struct inode *need_iput_tmp; - struct list_head *watches; - - /* - * We cannot __iget() an inode in state I_CLEAR, I_FREEING, - * I_WILL_FREE, or I_NEW which is fine because by that point - * the inode cannot have any associated watches. - */ - if (inode->i_state & (I_CLEAR|I_FREEING|I_WILL_FREE|I_NEW)) - continue; - - /* - * If i_count is zero, the inode cannot have any watches and - * doing an __iget/iput with MS_ACTIVE clear would actually - * evict all inodes with zero i_count from icache which is - * unnecessarily violent and may in fact be illegal to do. - */ - if (!atomic_read(&inode->i_count)) - continue; - - need_iput_tmp = need_iput; - need_iput = NULL; - /* In case inotify_remove_watch_locked() drops a reference. */ - if (inode != need_iput_tmp) - __iget(inode); - else - need_iput_tmp = NULL; - /* In case the dropping of a reference would nuke next_i. */ - if ((&next_i->i_sb_list != list) && - atomic_read(&next_i->i_count) && - !(next_i->i_state & (I_CLEAR | I_FREEING | - I_WILL_FREE))) { - __iget(next_i); - need_iput = next_i; - } - - /* - * We can safely drop inode_lock here because we hold - * references on both inode and next_i. Also no new inodes - * will be added since the umount has begun. Finally, - * iprune_mutex keeps shrink_icache_memory() away. - */ - spin_unlock(&inode_lock); - - if (need_iput_tmp) - iput(need_iput_tmp); - - /* for each watch, send IN_UNMOUNT and then remove it */ - mutex_lock(&inode->inotify_mutex); - watches = &inode->inotify_watches; - list_for_each_entry_safe(watch, next_w, watches, i_list) { - struct inotify_handle *ih= watch->ih; - get_inotify_watch(watch); - mutex_lock(&ih->mutex); - ih->in_ops->handle_event(watch, watch->wd, IN_UNMOUNT, 0, - NULL, NULL); - inotify_remove_watch_locked(ih, watch); - mutex_unlock(&ih->mutex); - put_inotify_watch(watch); - } - mutex_unlock(&inode->inotify_mutex); - iput(inode); - - spin_lock(&inode_lock); - } -} -EXPORT_SYMBOL_GPL(inotify_unmount_inodes); - -/** - * inotify_inode_is_dead - an inode has been deleted, cleanup any watches - * @inode: inode that is about to be removed - */ -void inotify_inode_is_dead(struct inode *inode) -{ - struct inotify_watch *watch, *next; - - mutex_lock(&inode->inotify_mutex); - list_for_each_entry_safe(watch, next, &inode->inotify_watches, i_list) { - struct inotify_handle *ih = watch->ih; - mutex_lock(&ih->mutex); - inotify_remove_watch_locked(ih, watch); - mutex_unlock(&ih->mutex); - } - mutex_unlock(&inode->inotify_mutex); -} -EXPORT_SYMBOL_GPL(inotify_inode_is_dead); - -/* Kernel Consumer API */ - -/** - * inotify_init - allocate and initialize an inotify instance - * @ops: caller's inotify operations - */ -struct inotify_handle *inotify_init(const struct inotify_operations *ops) -{ - struct inotify_handle *ih; - - ih = kmalloc(sizeof(struct inotify_handle), GFP_KERNEL); - if (unlikely(!ih)) - return ERR_PTR(-ENOMEM); - - idr_init(&ih->idr); - INIT_LIST_HEAD(&ih->watches); - mutex_init(&ih->mutex); - ih->last_wd = 0; - ih->in_ops = ops; - atomic_set(&ih->count, 0); - get_inotify_handle(ih); - - return ih; -} -EXPORT_SYMBOL_GPL(inotify_init); - -/** - * inotify_init_watch - initialize an inotify watch - * @watch: watch to initialize - */ -void inotify_init_watch(struct inotify_watch *watch) -{ - INIT_LIST_HEAD(&watch->h_list); - INIT_LIST_HEAD(&watch->i_list); - atomic_set(&watch->count, 0); - get_inotify_watch(watch); /* initial get */ -} -EXPORT_SYMBOL_GPL(inotify_init_watch); - -/* - * Watch removals suck violently. To kick the watch out we need (in this - * order) inode->inotify_mutex and ih->mutex. That's fine if we have - * a hold on inode; however, for all other cases we need to make damn sure - * we don't race with umount. We can *NOT* just grab a reference to a - * watch - inotify_unmount_inodes() will happily sail past it and we'll end - * with reference to inode potentially outliving its superblock. Ideally - * we just want to grab an active reference to superblock if we can; that - * will make sure we won't go into inotify_umount_inodes() until we are - * done. Cleanup is just deactivate_super(). However, that leaves a messy - * case - what if we *are* racing with umount() and active references to - * superblock can't be acquired anymore? We can bump ->s_count, grab - * ->s_umount, which will wait until the superblock is shut down and the - * watch in question is pining for fjords. - * - * And yes, this is far beyond mere "not very pretty"; so's the entire - * concept of inotify to start with. - */ - -/** - * pin_to_kill - pin the watch down for removal - * @ih: inotify handle - * @watch: watch to kill - * - * Called with ih->mutex held, drops it. Possible return values: - * 0 - nothing to do, it has died - * 1 - remove it, drop the reference and deactivate_super() - */ -static int pin_to_kill(struct inotify_handle *ih, struct inotify_watch *watch) -{ - struct super_block *sb = watch->inode->i_sb; - - if (atomic_inc_not_zero(&sb->s_active)) { - get_inotify_watch(watch); - mutex_unlock(&ih->mutex); - return 1; /* the best outcome */ - } - spin_lock(&sb_lock); - sb->s_count++; - spin_unlock(&sb_lock); - mutex_unlock(&ih->mutex); /* can't grab ->s_umount under it */ - down_read(&sb->s_umount); - /* fs is already shut down; the watch is dead */ - drop_super(sb); - return 0; -} - -static void unpin_and_kill(struct inotify_watch *watch) -{ - struct super_block *sb = watch->inode->i_sb; - put_inotify_watch(watch); - deactivate_super(sb); -} - -/** - * inotify_destroy - clean up and destroy an inotify instance - * @ih: inotify handle - */ -void inotify_destroy(struct inotify_handle *ih) -{ - /* - * Destroy all of the watches for this handle. Unfortunately, not very - * pretty. We cannot do a simple iteration over the list, because we - * do not know the inode until we iterate to the watch. But we need to - * hold inode->inotify_mutex before ih->mutex. The following works. - * - * AV: it had to become even uglier to start working ;-/ - */ - while (1) { - struct inotify_watch *watch; - struct list_head *watches; - struct super_block *sb; - struct inode *inode; - - mutex_lock(&ih->mutex); - watches = &ih->watches; - if (list_empty(watches)) { - mutex_unlock(&ih->mutex); - break; - } - watch = list_first_entry(watches, struct inotify_watch, h_list); - sb = watch->inode->i_sb; - if (!pin_to_kill(ih, watch)) - continue; - - inode = watch->inode; - mutex_lock(&inode->inotify_mutex); - mutex_lock(&ih->mutex); - - /* make sure we didn't race with another list removal */ - if (likely(idr_find(&ih->idr, watch->wd))) { - remove_watch_no_event(watch, ih); - put_inotify_watch(watch); - } - - mutex_unlock(&ih->mutex); - mutex_unlock(&inode->inotify_mutex); - unpin_and_kill(watch); - } - - /* free this handle: the put matching the get in inotify_init() */ - put_inotify_handle(ih); -} -EXPORT_SYMBOL_GPL(inotify_destroy); - -/** - * inotify_find_watch - find an existing watch for an (ih,inode) pair - * @ih: inotify handle - * @inode: inode to watch - * @watchp: pointer to existing inotify_watch - * - * Caller must pin given inode (via nameidata). - */ -s32 inotify_find_watch(struct inotify_handle *ih, struct inode *inode, - struct inotify_watch **watchp) -{ - struct inotify_watch *old; - int ret = -ENOENT; - - mutex_lock(&inode->inotify_mutex); - mutex_lock(&ih->mutex); - - old = inode_find_handle(inode, ih); - if (unlikely(old)) { - get_inotify_watch(old); /* caller must put watch */ - *watchp = old; - ret = old->wd; - } - - mutex_unlock(&ih->mutex); - mutex_unlock(&inode->inotify_mutex); - - return ret; -} -EXPORT_SYMBOL_GPL(inotify_find_watch); - -/** - * inotify_find_update_watch - find and update the mask of an existing watch - * @ih: inotify handle - * @inode: inode's watch to update - * @mask: mask of events to watch - * - * Caller must pin given inode (via nameidata). - */ -s32 inotify_find_update_watch(struct inotify_handle *ih, struct inode *inode, - u32 mask) -{ - struct inotify_watch *old; - int mask_add = 0; - int ret; - - if (mask & IN_MASK_ADD) - mask_add = 1; - - /* don't allow invalid bits: we don't want flags set */ - mask &= IN_ALL_EVENTS | IN_ONESHOT; - if (unlikely(!mask)) - return -EINVAL; - - mutex_lock(&inode->inotify_mutex); - mutex_lock(&ih->mutex); - - /* - * Handle the case of re-adding a watch on an (inode,ih) pair that we - * are already watching. We just update the mask and return its wd. - */ - old = inode_find_handle(inode, ih); - if (unlikely(!old)) { - ret = -ENOENT; - goto out; - } - - if (mask_add) - old->mask |= mask; - else - old->mask = mask; - ret = old->wd; -out: - mutex_unlock(&ih->mutex); - mutex_unlock(&inode->inotify_mutex); - return ret; -} -EXPORT_SYMBOL_GPL(inotify_find_update_watch); - -/** - * inotify_add_watch - add a watch to an inotify instance - * @ih: inotify handle - * @watch: caller allocated watch structure - * @inode: inode to watch - * @mask: mask of events to watch - * - * Caller must pin given inode (via nameidata). - * Caller must ensure it only calls inotify_add_watch() once per watch. - * Calls inotify_handle_get_wd() so may sleep. - */ -s32 inotify_add_watch(struct inotify_handle *ih, struct inotify_watch *watch, - struct inode *inode, u32 mask) -{ - int ret = 0; - int newly_watched; - - /* don't allow invalid bits: we don't want flags set */ - mask &= IN_ALL_EVENTS | IN_ONESHOT; - if (unlikely(!mask)) - return -EINVAL; - watch->mask = mask; - - mutex_lock(&inode->inotify_mutex); - mutex_lock(&ih->mutex); - - /* Initialize a new watch */ - ret = inotify_handle_get_wd(ih, watch); - if (unlikely(ret)) - goto out; - ret = watch->wd; - - /* save a reference to handle and bump the count to make it official */ - get_inotify_handle(ih); - watch->ih = ih; - - /* - * Save a reference to the inode and bump the ref count to make it - * official. We hold a reference to nameidata, which makes this safe. - */ - watch->inode = igrab(inode); - - /* Add the watch to the handle's and the inode's list */ - newly_watched = !inotify_inode_watched(inode); - list_add(&watch->h_list, &ih->watches); - list_add(&watch->i_list, &inode->inotify_watches); - /* - * Set child flags _after_ adding the watch, so there is no race - * windows where newly instantiated children could miss their parent's - * watched flag. - */ - if (newly_watched) - set_dentry_child_flags(inode, 1); - -out: - mutex_unlock(&ih->mutex); - mutex_unlock(&inode->inotify_mutex); - return ret; -} -EXPORT_SYMBOL_GPL(inotify_add_watch); - -/** - * inotify_clone_watch - put the watch next to existing one - * @old: already installed watch - * @new: new watch - * - * Caller must hold the inotify_mutex of inode we are dealing with; - * it is expected to remove the old watch before unlocking the inode. - */ -s32 inotify_clone_watch(struct inotify_watch *old, struct inotify_watch *new) -{ - struct inotify_handle *ih = old->ih; - int ret = 0; - - new->mask = old->mask; - new->ih = ih; - - mutex_lock(&ih->mutex); - - /* Initialize a new watch */ - ret = inotify_handle_get_wd(ih, new); - if (unlikely(ret)) - goto out; - ret = new->wd; - - get_inotify_handle(ih); - - new->inode = igrab(old->inode); - - list_add(&new->h_list, &ih->watches); - list_add(&new->i_list, &old->inode->inotify_watches); -out: - mutex_unlock(&ih->mutex); - return ret; -} - -void inotify_evict_watch(struct inotify_watch *watch) -{ - get_inotify_watch(watch); - mutex_lock(&watch->ih->mutex); - inotify_remove_watch_locked(watch->ih, watch); - mutex_unlock(&watch->ih->mutex); -} - -/** - * inotify_rm_wd - remove a watch from an inotify instance - * @ih: inotify handle - * @wd: watch descriptor to remove - * - * Can sleep. - */ -int inotify_rm_wd(struct inotify_handle *ih, u32 wd) -{ - struct inotify_watch *watch; - struct super_block *sb; - struct inode *inode; - - mutex_lock(&ih->mutex); - watch = idr_find(&ih->idr, wd); - if (unlikely(!watch)) { - mutex_unlock(&ih->mutex); - return -EINVAL; - } - sb = watch->inode->i_sb; - if (!pin_to_kill(ih, watch)) - return 0; - - inode = watch->inode; - - mutex_lock(&inode->inotify_mutex); - mutex_lock(&ih->mutex); - - /* make sure that we did not race */ - if (likely(idr_find(&ih->idr, wd) == watch)) - inotify_remove_watch_locked(ih, watch); - - mutex_unlock(&ih->mutex); - mutex_unlock(&inode->inotify_mutex); - unpin_and_kill(watch); - - return 0; -} -EXPORT_SYMBOL_GPL(inotify_rm_wd); - -/** - * inotify_rm_watch - remove a watch from an inotify instance - * @ih: inotify handle - * @watch: watch to remove - * - * Can sleep. - */ -int inotify_rm_watch(struct inotify_handle *ih, - struct inotify_watch *watch) -{ - return inotify_rm_wd(ih, watch->wd); -} -EXPORT_SYMBOL_GPL(inotify_rm_watch); - -/* - * inotify_setup - core initialization function - */ -static int __init inotify_setup(void) -{ - BUILD_BUG_ON(IN_ACCESS != FS_ACCESS); - BUILD_BUG_ON(IN_MODIFY != FS_MODIFY); - BUILD_BUG_ON(IN_ATTRIB != FS_ATTRIB); - BUILD_BUG_ON(IN_CLOSE_WRITE != FS_CLOSE_WRITE); - BUILD_BUG_ON(IN_CLOSE_NOWRITE != FS_CLOSE_NOWRITE); - BUILD_BUG_ON(IN_OPEN != FS_OPEN); - BUILD_BUG_ON(IN_MOVED_FROM != FS_MOVED_FROM); - BUILD_BUG_ON(IN_MOVED_TO != FS_MOVED_TO); - BUILD_BUG_ON(IN_CREATE != FS_CREATE); - BUILD_BUG_ON(IN_DELETE != FS_DELETE); - BUILD_BUG_ON(IN_DELETE_SELF != FS_DELETE_SELF); - BUILD_BUG_ON(IN_MOVE_SELF != FS_MOVE_SELF); - BUILD_BUG_ON(IN_Q_OVERFLOW != FS_Q_OVERFLOW); - - BUILD_BUG_ON(IN_UNMOUNT != FS_UNMOUNT); - BUILD_BUG_ON(IN_ISDIR != FS_IN_ISDIR); - BUILD_BUG_ON(IN_IGNORED != FS_IN_IGNORED); - BUILD_BUG_ON(IN_ONESHOT != FS_IN_ONESHOT); - - atomic_set(&inotify_cookie, 0); - - return 0; -} - -module_init(inotify_setup); diff --git a/fs/notify/inotify/inotify.h b/fs/notify/inotify/inotify.h index f234f3a..b6642e4 100644 --- a/fs/notify/inotify/inotify.h +++ b/fs/notify/inotify/inotify.h @@ -9,13 +9,12 @@ struct inotify_event_private_data { int wd; }; -struct inotify_inode_mark_entry { - /* fsnotify_mark_entry MUST be the first thing */ - struct fsnotify_mark_entry fsn_entry; +struct inotify_inode_mark { + struct fsnotify_mark fsn_mark; int wd; }; -extern void inotify_ignored_and_remove_idr(struct fsnotify_mark_entry *entry, +extern void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark, struct fsnotify_group *group); extern void inotify_free_event_priv(struct fsnotify_event_private_data *event_priv); diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c index e27960c..5e73eeb 100644 --- a/fs/notify/inotify/inotify_fsnotify.c +++ b/fs/notify/inotify/inotify_fsnotify.c @@ -22,6 +22,7 @@ * General Public License for more details. */ +#include <linux/dcache.h> /* d_unlinked */ #include <linux/fs.h> /* struct inode */ #include <linux/fsnotify_backend.h> #include <linux/inotify.h> @@ -32,26 +33,84 @@ #include "inotify.h" -static int inotify_handle_event(struct fsnotify_group *group, struct fsnotify_event *event) +/* + * Check if 2 events contain the same information. We do not compare private data + * but at this moment that isn't a problem for any know fsnotify listeners. + */ +static bool event_compare(struct fsnotify_event *old, struct fsnotify_event *new) +{ + if ((old->mask == new->mask) && + (old->to_tell == new->to_tell) && + (old->data_type == new->data_type) && + (old->name_len == new->name_len)) { + switch (old->data_type) { + case (FSNOTIFY_EVENT_INODE): + /* remember, after old was put on the wait_q we aren't + * allowed to look at the inode any more, only thing + * left to check was if the file_name is the same */ + if (!old->name_len || + !strcmp(old->file_name, new->file_name)) + return true; + break; + case (FSNOTIFY_EVENT_FILE): + if ((old->file->f_path.mnt == new->file->f_path.mnt) && + (old->file->f_path.dentry == new->file->f_path.dentry)) + return true; + break; + case (FSNOTIFY_EVENT_NONE): + if (old->mask & FS_Q_OVERFLOW) + return true; + else if (old->mask & FS_IN_IGNORED) + return false; + return true; + }; + } + return false; +} + +static struct fsnotify_event *inotify_merge(struct list_head *list, + struct fsnotify_event *event) { - struct fsnotify_mark_entry *entry; - struct inotify_inode_mark_entry *ientry; + struct fsnotify_event_holder *last_holder; + struct fsnotify_event *last_event; + + /* and the list better be locked by something too */ + spin_lock(&event->lock); + + last_holder = list_entry(list->prev, struct fsnotify_event_holder, event_list); + last_event = last_holder->event; + if (event_compare(last_event, event)) + fsnotify_get_event(last_event); + else + last_event = NULL; + + spin_unlock(&event->lock); + + return last_event; +} + +static int inotify_handle_event(struct fsnotify_group *group, + struct fsnotify_mark *inode_mark, + struct fsnotify_mark *vfsmount_mark, + struct fsnotify_event *event) +{ + struct inotify_inode_mark *i_mark; struct inode *to_tell; struct inotify_event_private_data *event_priv; struct fsnotify_event_private_data *fsn_event_priv; - int wd, ret; + struct fsnotify_event *added_event; + int wd, ret = 0; + + BUG_ON(vfsmount_mark); + + pr_debug("%s: group=%p event=%p to_tell=%p mask=%x\n", __func__, group, + event, event->to_tell, event->mask); to_tell = event->to_tell; - spin_lock(&to_tell->i_lock); - entry = fsnotify_find_mark_entry(group, to_tell); - spin_unlock(&to_tell->i_lock); - /* race with watch removal? We already passes should_send */ - if (unlikely(!entry)) - return 0; - ientry = container_of(entry, struct inotify_inode_mark_entry, - fsn_entry); - wd = ientry->wd; + i_mark = container_of(inode_mark, struct inotify_inode_mark, + fsn_mark); + wd = i_mark->wd; event_priv = kmem_cache_alloc(event_priv_cachep, GFP_KERNEL); if (unlikely(!event_priv)) @@ -62,48 +121,40 @@ static int inotify_handle_event(struct fsnotify_group *group, struct fsnotify_ev fsn_event_priv->group = group; event_priv->wd = wd; - ret = fsnotify_add_notify_event(group, event, fsn_event_priv); - if (ret) { + added_event = fsnotify_add_notify_event(group, event, fsn_event_priv, inotify_merge); + if (added_event) { inotify_free_event_priv(fsn_event_priv); - /* EEXIST says we tail matched, EOVERFLOW isn't something - * to report up the stack. */ - if ((ret == -EEXIST) || - (ret == -EOVERFLOW)) - ret = 0; + if (!IS_ERR(added_event)) + fsnotify_put_event(added_event); + else + ret = PTR_ERR(added_event); } - /* - * If we hold the entry until after the event is on the queue - * IN_IGNORED won't be able to pass this event in the queue - */ - fsnotify_put_mark(entry); + if (inode_mark->mask & IN_ONESHOT) + fsnotify_destroy_mark(inode_mark); return ret; } -static void inotify_freeing_mark(struct fsnotify_mark_entry *entry, struct fsnotify_group *group) +static void inotify_freeing_mark(struct fsnotify_mark *fsn_mark, struct fsnotify_group *group) { - inotify_ignored_and_remove_idr(entry, group); + inotify_ignored_and_remove_idr(fsn_mark, group); } -static bool inotify_should_send_event(struct fsnotify_group *group, struct inode *inode, __u32 mask) +static bool inotify_should_send_event(struct fsnotify_group *group, struct inode *inode, + struct fsnotify_mark *inode_mark, + struct fsnotify_mark *vfsmount_mark, + __u32 mask, void *data, int data_type) { - struct fsnotify_mark_entry *entry; - bool send; - - spin_lock(&inode->i_lock); - entry = fsnotify_find_mark_entry(group, inode); - spin_unlock(&inode->i_lock); - if (!entry) - return false; + if ((inode_mark->mask & FS_EXCL_UNLINK) && + (data_type == FSNOTIFY_EVENT_FILE)) { + struct file *file = data; - mask = (mask & ~FS_EVENT_ON_CHILD); - send = (entry->mask & mask); - - /* find took a reference */ - fsnotify_put_mark(entry); + if (d_unlinked(file->f_path.dentry)) + return false; + } - return send; + return true; } /* @@ -115,18 +166,18 @@ static bool inotify_should_send_event(struct fsnotify_group *group, struct inode */ static int idr_callback(int id, void *p, void *data) { - struct fsnotify_mark_entry *entry; - struct inotify_inode_mark_entry *ientry; + struct fsnotify_mark *fsn_mark; + struct inotify_inode_mark *i_mark; static bool warned = false; if (warned) return 0; warned = true; - entry = p; - ientry = container_of(entry, struct inotify_inode_mark_entry, fsn_entry); + fsn_mark = p; + i_mark = container_of(fsn_mark, struct inotify_inode_mark, fsn_mark); - WARN(1, "inotify closing but id=%d for entry=%p in group=%p still in " + WARN(1, "inotify closing but id=%d for fsn_mark=%p in group=%p still in " "idr. Probably leaking memory\n", id, p, data); /* @@ -135,9 +186,9 @@ static int idr_callback(int id, void *p, void *data) * out why we got here and the panic is no worse than the original * BUG() that was here. */ - if (entry) - printk(KERN_WARNING "entry->group=%p inode=%p wd=%d\n", - entry->group, entry->inode, ientry->wd); + if (fsn_mark) + printk(KERN_WARNING "fsn_mark->group=%p inode=%p wd=%d\n", + fsn_mark->group, fsn_mark->i.inode, i_mark->wd); return 0; } diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c index e46ca68..bf7f6d7 100644 --- a/fs/notify/inotify/inotify_user.c +++ b/fs/notify/inotify/inotify_user.c @@ -46,17 +46,11 @@ /* 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 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; -/* - * 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> @@ -96,11 +90,14 @@ 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); + /* + * everything should accept their own ignored, cares about children, + * and should receive events when the inode is unmounted + */ + mask = (FS_IN_IGNORED | FS_EVENT_ON_CHILD | FS_UNMOUNT); /* mask off the flags used to open the fd */ - mask |= (arg & (IN_ALL_EVENTS | IN_ONESHOT)); + mask |= (arg & (IN_ALL_EVENTS | IN_ONESHOT | IN_EXCL_UNLINK)); return mask; } @@ -144,6 +141,8 @@ static struct fsnotify_event *get_one_event(struct fsnotify_group *group, event = fsnotify_peek_notify_event(group); + pr_debug("%s: group=%p event=%p\n", __func__, group, event); + if (event->name_len) event_size += roundup(event->name_len + 1, event_size); @@ -173,6 +172,8 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group, size_t event_size = sizeof(struct inotify_event); size_t name_len = 0; + pr_debug("%s: group=%p event=%p\n", __func__, group, event); + /* we get the inotify watch descriptor from the event private data */ spin_lock(&event->lock); fsn_priv = fsnotify_remove_priv_from_event(group, event); @@ -245,6 +246,8 @@ static ssize_t inotify_read(struct file *file, char __user *buf, kevent = get_one_event(group, count); mutex_unlock(&group->notification_mutex); + pr_debug("%s: group=%p kevent=%p\n", __func__, group, kevent); + if (kevent) { ret = PTR_ERR(kevent); if (IS_ERR(kevent)) @@ -289,6 +292,8 @@ static int inotify_release(struct inode *ignored, struct file *file) struct fsnotify_group *group = file->private_data; struct user_struct *user = group->inotify_data.user; + pr_debug("%s: group=%p\n", __func__, group); + fsnotify_clear_marks_by_group(group); /* free this group, matching get was inotify_init->fsnotify_obtain_group */ @@ -312,6 +317,8 @@ static long inotify_ioctl(struct file *file, unsigned int cmd, group = file->private_data; p = (void __user *) arg; + pr_debug("%s: group=%p cmd=%u\n", __func__, group, cmd); + switch (cmd) { case FIONREAD: mutex_lock(&group->notification_mutex); @@ -357,59 +364,159 @@ static int inotify_find_inode(const char __user *dirname, struct path *path, uns return error; } +static int inotify_add_to_idr(struct idr *idr, spinlock_t *idr_lock, + int *last_wd, + struct inotify_inode_mark *i_mark) +{ + int ret; + + do { + if (unlikely(!idr_pre_get(idr, GFP_KERNEL))) + return -ENOMEM; + + spin_lock(idr_lock); + ret = idr_get_new_above(idr, i_mark, *last_wd + 1, + &i_mark->wd); + /* we added the mark to the idr, take a reference */ + if (!ret) { + *last_wd = i_mark->wd; + fsnotify_get_mark(&i_mark->fsn_mark); + } + spin_unlock(idr_lock); + } while (ret == -EAGAIN); + + return ret; +} + +static struct inotify_inode_mark *inotify_idr_find_locked(struct fsnotify_group *group, + int wd) +{ + struct idr *idr = &group->inotify_data.idr; + spinlock_t *idr_lock = &group->inotify_data.idr_lock; + struct inotify_inode_mark *i_mark; + + assert_spin_locked(idr_lock); + + i_mark = idr_find(idr, wd); + if (i_mark) { + struct fsnotify_mark *fsn_mark = &i_mark->fsn_mark; + + fsnotify_get_mark(fsn_mark); + /* One ref for being in the idr, one ref we just took */ + BUG_ON(atomic_read(&fsn_mark->refcnt) < 2); + } + + return i_mark; +} + +static struct inotify_inode_mark *inotify_idr_find(struct fsnotify_group *group, + int wd) +{ + struct inotify_inode_mark *i_mark; + spinlock_t *idr_lock = &group->inotify_data.idr_lock; + + spin_lock(idr_lock); + i_mark = inotify_idr_find_locked(group, wd); + spin_unlock(idr_lock); + + return i_mark; +} + +static void do_inotify_remove_from_idr(struct fsnotify_group *group, + struct inotify_inode_mark *i_mark) +{ + struct idr *idr = &group->inotify_data.idr; + spinlock_t *idr_lock = &group->inotify_data.idr_lock; + int wd = i_mark->wd; + + assert_spin_locked(idr_lock); + + idr_remove(idr, wd); + + /* removed from the idr, drop that ref */ + fsnotify_put_mark(&i_mark->fsn_mark); +} + /* * Remove the mark from the idr (if present) and drop the reference * on the mark because it was in the idr. */ static void inotify_remove_from_idr(struct fsnotify_group *group, - struct inotify_inode_mark_entry *ientry) + struct inotify_inode_mark *i_mark) { - struct idr *idr; - struct fsnotify_mark_entry *entry; - struct inotify_inode_mark_entry *found_ientry; + spinlock_t *idr_lock = &group->inotify_data.idr_lock; + struct inotify_inode_mark *found_i_mark = NULL; int wd; - spin_lock(&group->inotify_data.idr_lock); - idr = &group->inotify_data.idr; - wd = ientry->wd; + spin_lock(idr_lock); + wd = i_mark->wd; - if (wd == -1) + /* + * does this i_mark think it is in the idr? we shouldn't get called + * if it wasn't.... + */ + if (wd == -1) { + WARN_ONCE(1, "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p" + " i_mark->inode=%p\n", __func__, i_mark, i_mark->wd, + i_mark->fsn_mark.group, i_mark->fsn_mark.i.inode); goto out; + } - entry = idr_find(&group->inotify_data.idr, wd); - if (unlikely(!entry)) + /* Lets look in the idr to see if we find it */ + found_i_mark = inotify_idr_find_locked(group, wd); + if (unlikely(!found_i_mark)) { + WARN_ONCE(1, "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p" + " i_mark->inode=%p\n", __func__, i_mark, i_mark->wd, + i_mark->fsn_mark.group, i_mark->fsn_mark.i.inode); goto out; + } - found_ientry = container_of(entry, struct inotify_inode_mark_entry, fsn_entry); - if (unlikely(found_ientry != ientry)) { - /* We found an entry in the idr with the right wd, but it's - * not the entry we were told to remove. eparis seriously - * fucked up somewhere. */ - WARN_ON(1); - ientry->wd = -1; + /* + * We found an mark in the idr at the right wd, but it's + * not the mark we were told to remove. eparis seriously + * fucked up somewhere. + */ + if (unlikely(found_i_mark != i_mark)) { + WARN_ONCE(1, "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p " + "mark->inode=%p found_i_mark=%p found_i_mark->wd=%d " + "found_i_mark->group=%p found_i_mark->inode=%p\n", + __func__, i_mark, i_mark->wd, i_mark->fsn_mark.group, + i_mark->fsn_mark.i.inode, found_i_mark, found_i_mark->wd, + found_i_mark->fsn_mark.group, + found_i_mark->fsn_mark.i.inode); goto out; } - /* One ref for being in the idr, one ref held by the caller */ - BUG_ON(atomic_read(&entry->refcnt) < 2); - - idr_remove(idr, wd); - ientry->wd = -1; + /* + * One ref for being in the idr + * one ref held by the caller trying to kill us + * one ref grabbed by inotify_idr_find + */ + if (unlikely(atomic_read(&i_mark->fsn_mark.refcnt) < 3)) { + printk(KERN_ERR "%s: i_mark=%p i_mark->wd=%d i_mark->group=%p" + " i_mark->inode=%p\n", __func__, i_mark, i_mark->wd, + i_mark->fsn_mark.group, i_mark->fsn_mark.i.inode); + /* we can't really recover with bad ref cnting.. */ + BUG(); + } - /* removed from the idr, drop that ref */ - fsnotify_put_mark(entry); + do_inotify_remove_from_idr(group, i_mark); out: - spin_unlock(&group->inotify_data.idr_lock); + /* match the ref taken by inotify_idr_find_locked() */ + if (found_i_mark) + fsnotify_put_mark(&found_i_mark->fsn_mark); + i_mark->wd = -1; + spin_unlock(idr_lock); } /* * Send IN_IGNORED for this wd, remove this wd from the idr. */ -void inotify_ignored_and_remove_idr(struct fsnotify_mark_entry *entry, +void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark, struct fsnotify_group *group) { - struct inotify_inode_mark_entry *ientry; - struct fsnotify_event *ignored_event; + struct inotify_inode_mark *i_mark; + struct fsnotify_event *ignored_event, *notify_event; struct inotify_event_private_data *event_priv; struct fsnotify_event_private_data *fsn_event_priv; int ret; @@ -420,7 +527,7 @@ void inotify_ignored_and_remove_idr(struct fsnotify_mark_entry *entry, if (!ignored_event) return; - ientry = container_of(entry, struct inotify_inode_mark_entry, fsn_entry); + i_mark = container_of(fsn_mark, struct inotify_inode_mark, fsn_mark); event_priv = kmem_cache_alloc(event_priv_cachep, GFP_NOFS); if (unlikely(!event_priv)) @@ -429,37 +536,44 @@ void inotify_ignored_and_remove_idr(struct fsnotify_mark_entry *entry, fsn_event_priv = &event_priv->fsnotify_event_priv_data; fsn_event_priv->group = group; - event_priv->wd = ientry->wd; - - ret = fsnotify_add_notify_event(group, ignored_event, fsn_event_priv); - if (ret) + event_priv->wd = i_mark->wd; + + notify_event = fsnotify_add_notify_event(group, ignored_event, fsn_event_priv, NULL); + if (notify_event) { + if (IS_ERR(notify_event)) + ret = PTR_ERR(notify_event); + else + fsnotify_put_event(notify_event); inotify_free_event_priv(fsn_event_priv); + } skip_send_ignore: /* matches the reference taken when the event was created */ fsnotify_put_event(ignored_event); - /* remove this entry from the idr */ - inotify_remove_from_idr(group, ientry); + /* remove this mark from the idr */ + inotify_remove_from_idr(group, i_mark); atomic_dec(&group->inotify_data.user->inotify_watches); } /* ding dong the mark is dead */ -static void inotify_free_mark(struct fsnotify_mark_entry *entry) +static void inotify_free_mark(struct fsnotify_mark *fsn_mark) { - struct inotify_inode_mark_entry *ientry = (struct inotify_inode_mark_entry *)entry; + struct inotify_inode_mark *i_mark; + + i_mark = container_of(fsn_mark, struct inotify_inode_mark, fsn_mark); - kmem_cache_free(inotify_inode_mark_cachep, ientry); + kmem_cache_free(inotify_inode_mark_cachep, i_mark); } static int inotify_update_existing_watch(struct fsnotify_group *group, struct inode *inode, u32 arg) { - struct fsnotify_mark_entry *entry; - struct inotify_inode_mark_entry *ientry; + struct fsnotify_mark *fsn_mark; + struct inotify_inode_mark *i_mark; __u32 old_mask, new_mask; __u32 mask; int add = (arg & IN_MASK_ADD); @@ -467,52 +581,43 @@ static int inotify_update_existing_watch(struct fsnotify_group *group, /* don't allow invalid bits: we don't want flags set */ mask = inotify_arg_to_mask(arg); - if (unlikely(!mask)) + if (unlikely(!(mask & IN_ALL_EVENTS))) return -EINVAL; - spin_lock(&inode->i_lock); - entry = fsnotify_find_mark_entry(group, inode); - spin_unlock(&inode->i_lock); - if (!entry) + fsn_mark = fsnotify_find_inode_mark(group, inode); + if (!fsn_mark) return -ENOENT; - ientry = container_of(entry, struct inotify_inode_mark_entry, fsn_entry); + i_mark = container_of(fsn_mark, struct inotify_inode_mark, fsn_mark); - spin_lock(&entry->lock); + spin_lock(&fsn_mark->lock); - old_mask = entry->mask; - if (add) { - entry->mask |= mask; - new_mask = entry->mask; - } else { - entry->mask = mask; - new_mask = entry->mask; - } + old_mask = fsn_mark->mask; + if (add) + fsnotify_set_mark_mask_locked(fsn_mark, (fsn_mark->mask | mask)); + else + fsnotify_set_mark_mask_locked(fsn_mark, mask); + new_mask = fsn_mark->mask; - spin_unlock(&entry->lock); + spin_unlock(&fsn_mark->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? */ + /* more bits in this fsn_mark 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 */ + /* update the inode with this new fsn_mark */ 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 the wd */ - ret = ientry->wd; + ret = i_mark->wd; - /* match the get from fsnotify_find_mark_entry() */ - fsnotify_put_mark(entry); + /* match the get from fsnotify_find_mark() */ + fsnotify_put_mark(fsn_mark); return ret; } @@ -521,73 +626,51 @@ static int inotify_new_watch(struct fsnotify_group *group, struct inode *inode, u32 arg) { - struct inotify_inode_mark_entry *tmp_ientry; + struct inotify_inode_mark *tmp_i_mark; __u32 mask; int ret; + struct idr *idr = &group->inotify_data.idr; + spinlock_t *idr_lock = &group->inotify_data.idr_lock; /* don't allow invalid bits: we don't want flags set */ mask = inotify_arg_to_mask(arg); - if (unlikely(!mask)) + if (unlikely(!(mask & IN_ALL_EVENTS))) return -EINVAL; - tmp_ientry = kmem_cache_alloc(inotify_inode_mark_cachep, GFP_KERNEL); - if (unlikely(!tmp_ientry)) + tmp_i_mark = kmem_cache_alloc(inotify_inode_mark_cachep, GFP_KERNEL); + if (unlikely(!tmp_i_mark)) return -ENOMEM; - fsnotify_init_mark(&tmp_ientry->fsn_entry, inotify_free_mark); - tmp_ientry->fsn_entry.mask = mask; - tmp_ientry->wd = -1; + fsnotify_init_mark(&tmp_i_mark->fsn_mark, inotify_free_mark); + tmp_i_mark->fsn_mark.mask = mask; + tmp_i_mark->wd = -1; ret = -ENOSPC; if (atomic_read(&group->inotify_data.user->inotify_watches) >= inotify_max_user_watches) goto out_err; -retry: - ret = -ENOMEM; - if (unlikely(!idr_pre_get(&group->inotify_data.idr, GFP_KERNEL))) - goto out_err; - /* we are putting the mark on the idr, take a reference */ - fsnotify_get_mark(&tmp_ientry->fsn_entry); - - spin_lock(&group->inotify_data.idr_lock); - ret = idr_get_new_above(&group->inotify_data.idr, &tmp_ientry->fsn_entry, - group->inotify_data.last_wd+1, - &tmp_ientry->wd); - spin_unlock(&group->inotify_data.idr_lock); - if (ret) { - /* we didn't get on the idr, drop the idr reference */ - fsnotify_put_mark(&tmp_ientry->fsn_entry); - - /* idr was out of memory allocate and try again */ - if (ret == -EAGAIN) - goto retry; + ret = inotify_add_to_idr(idr, idr_lock, &group->inotify_data.last_wd, + tmp_i_mark); + if (ret) goto out_err; - } /* we are on the idr, now get on the inode */ - ret = fsnotify_add_mark(&tmp_ientry->fsn_entry, group, inode); + ret = fsnotify_add_mark(&tmp_i_mark->fsn_mark, group, inode, NULL, 0); if (ret) { /* we failed to get on the inode, get off the idr */ - inotify_remove_from_idr(group, tmp_ientry); + inotify_remove_from_idr(group, tmp_i_mark); goto out_err; } - /* update the idr hint, who cares about races, it's just a hint */ - group->inotify_data.last_wd = tmp_ientry->wd; - /* increment the number of watches the user has */ atomic_inc(&group->inotify_data.user->inotify_watches); - /* return the watch descriptor for this new entry */ - ret = tmp_ientry->wd; - - /* if this mark added a new event update the group mask */ - if (mask & ~group->mask) - fsnotify_recalc_group_mask(group); + /* return the watch descriptor for this new mark */ + ret = tmp_i_mark->wd; out_err: - /* match the ref from fsnotify_init_markentry() */ - fsnotify_put_mark(&tmp_ientry->fsn_entry); + /* match the ref from fsnotify_init_mark() */ + fsnotify_put_mark(&tmp_i_mark->fsn_mark); return ret; } @@ -616,11 +699,8 @@ retry: 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); + group = fsnotify_alloc_group(&inotify_fsnotify_ops); if (IS_ERR(group)) return group; @@ -726,7 +806,7 @@ fput_and_out: SYSCALL_DEFINE2(inotify_rm_watch, int, fd, __s32, wd) { struct fsnotify_group *group; - struct fsnotify_mark_entry *entry; + struct inotify_inode_mark *i_mark; struct file *filp; int ret = 0, fput_needed; @@ -735,25 +815,23 @@ SYSCALL_DEFINE2(inotify_rm_watch, int, fd, __s32, wd) return -EBADF; /* verify that this is indeed an inotify instance */ - if (unlikely(filp->f_op != &inotify_fops)) { - ret = -EINVAL; + ret = -EINVAL; + if (unlikely(filp->f_op != &inotify_fops)) 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; + ret = -EINVAL; + i_mark = inotify_idr_find(group, wd); + if (unlikely(!i_mark)) goto out; - } - fsnotify_get_mark(entry); - spin_unlock(&group->inotify_data.idr_lock); - fsnotify_destroy_mark_by_entry(entry); - fsnotify_put_mark(entry); + ret = 0; + + fsnotify_destroy_mark(&i_mark->fsn_mark); + + /* match ref taken by inotify_idr_find */ + fsnotify_put_mark(&i_mark->fsn_mark); out: fput_light(filp, fput_needed); @@ -767,7 +845,28 @@ out: */ static int __init inotify_user_setup(void) { - inotify_inode_mark_cachep = KMEM_CACHE(inotify_inode_mark_entry, SLAB_PANIC); + BUILD_BUG_ON(IN_ACCESS != FS_ACCESS); + BUILD_BUG_ON(IN_MODIFY != FS_MODIFY); + BUILD_BUG_ON(IN_ATTRIB != FS_ATTRIB); + BUILD_BUG_ON(IN_CLOSE_WRITE != FS_CLOSE_WRITE); + BUILD_BUG_ON(IN_CLOSE_NOWRITE != FS_CLOSE_NOWRITE); + BUILD_BUG_ON(IN_OPEN != FS_OPEN); + BUILD_BUG_ON(IN_MOVED_FROM != FS_MOVED_FROM); + BUILD_BUG_ON(IN_MOVED_TO != FS_MOVED_TO); + BUILD_BUG_ON(IN_CREATE != FS_CREATE); + BUILD_BUG_ON(IN_DELETE != FS_DELETE); + BUILD_BUG_ON(IN_DELETE_SELF != FS_DELETE_SELF); + BUILD_BUG_ON(IN_MOVE_SELF != FS_MOVE_SELF); + BUILD_BUG_ON(IN_UNMOUNT != FS_UNMOUNT); + BUILD_BUG_ON(IN_Q_OVERFLOW != FS_Q_OVERFLOW); + BUILD_BUG_ON(IN_IGNORED != FS_IN_IGNORED); + BUILD_BUG_ON(IN_EXCL_UNLINK != FS_EXCL_UNLINK); + BUILD_BUG_ON(IN_ISDIR != FS_IN_ISDIR); + BUILD_BUG_ON(IN_ONESHOT != FS_IN_ONESHOT); + + BUG_ON(hweight32(ALL_INOTIFY_BITS) != 21); + + inotify_inode_mark_cachep = KMEM_CACHE(inotify_inode_mark, SLAB_PANIC); event_priv_cachep = KMEM_CACHE(inotify_event_private_data, SLAB_PANIC); inotify_max_queued_events = 16384; |