[PATCH 2/2] updated filesystem auditing patches for lspp test kernel
Amy Griffis
amy.griffis at hp.com
Tue Apr 11 02:26:21 UTC 2006
Serge E. Hallyn wrote: [Mon Apr 10 2006, 01:56:26PM EDT]
> Hard to give this a meaningful review - particularly the first patch,
> a large part of which seemed to be moving functionality from one file to
> another.
FWIW, it may help to diff inotify_user.c against an unpatched
inotify.c (included below for reference). The essence of the inotify
patch is *how* the current functionality is split between kernel API
and userspace support. There isn't much new code.
> Quoting Amy Griffis (amy.griffis at hp.com):
> > +/* Initialize a watch entry. */
> > +static inline struct audit_watch *audit_init_watch(char *path)
> > +{
> > + struct audit_watch *watch;
> > +
> > + watch = kzalloc(sizeof(*watch), GFP_KERNEL);
> > + if (unlikely(!watch))
> > + return ERR_PTR(-ENOMEM);
> ...
> > + watch = audit_init_watch(path);
> > + if (unlikely(IS_ERR(watch)))
> > + return PTR_ERR(watch);
>
> Ok, but
>
> > + new = audit_init_watch(path);
> > + if (unlikely(!new)) {
> > + kfree(path);
> > + return ERR_PTR(-ENOMEM);
> > + }
>
> not ok
thanks
--- a/fs/inotify.c 2006-04-10 22:00:02.000000000 -0400
+++ b/fs/inotify_user.c 2006-04-10 22:13:14.000000000 -0400
@@ -18,11 +18,8 @@
* General Public License for more details.
*/
-#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
-#include <linux/spinlock.h>
-#include <linux/idr.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/file.h>
@@ -31,14 +28,11 @@
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/list.h>
-#include <linux/writeback.h>
#include <linux/inotify.h>
#include <linux/syscalls.h>
#include <asm/ioctls.h>
-static atomic_t inotify_cookie;
-
static kmem_cache_t *watch_cachep __read_mostly;
static kmem_cache_t *event_cachep __read_mostly;
@@ -52,27 +46,21 @@ int inotify_max_queued_events __read_mos
/*
* 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_dev->mutex (protects inotify_device and watches->d_list)
+ * inotify_dev->up_mutex (ensures we don't re-add the same watch)
+ * inode->inotify_mutex (protects inode's watch list)
+ * inotify_handle->mutex (protects inotify_handle's watch list)
+ * inotify_dev->ev_mutex (protects device's event queue)
*/
/*
- * Lifetimes of the three main data structures--inotify_device, inode, and
- * inotify_watch--are managed by reference count.
- *
- * inotify_device: Lifetime is from inotify_init() until release. Additional
- * references can bump the count via get_inotify_dev() and drop the count via
- * put_inotify_dev().
+ * Lifetimes of the main data structures:
*
- * inotify_watch: Lifetime is from create_watch() to destory_watch().
- * Additional references can bump the count via get_inotify_watch() and drop
- * the count via put_inotify_watch().
+ * inotify_device: Lifetime is managed by reference count, from
+ * sys_inotify_init() until release. Additional references can bump the count
+ * via get_inotify_dev() and drop the count via put_inotify_dev().
*
- * inode: Pinned so long as the inode is associated with a watch, from
- * create_watch() to put_inotify_watch().
+ * inotify_user_watch: Lifetime is from create_watch() to the receipt of an
+ * IN_IGNORED event from inotify.
*/
/*
@@ -82,16 +70,15 @@ int inotify_max_queued_events __read_mos
*/
struct inotify_device {
wait_queue_head_t wq; /* wait queue for i/o */
- struct idr idr; /* idr mapping wd -> watch */
- struct mutex mutex; /* protects this bad boy */
+ struct mutex ev_mutex; /* protects event queue */
+ struct mutex up_mutex; /* synchronizes watch updates */
struct list_head events; /* list of queued events */
- struct list_head watches; /* list of watches */
atomic_t count; /* reference count */
struct user_struct *user; /* user who opened this dev */
+ struct inotify_handle *ih; /* inotify handle */
unsigned int queue_size; /* size of the queue (bytes) */
unsigned int event_count; /* number of pending events */
unsigned int max_events; /* maximum number of events */
- u32 last_wd; /* the last wd allocated */
};
/*
@@ -100,7 +87,7 @@ struct inotify_device {
* device. In read(), this list is walked and all events that can fit in the
* buffer are returned.
*
- * Protected by dev->mutex of the device in which we are queued.
+ * Protected by dev->ev_mutex of the device in which we are queued.
*/
struct inotify_kernel_event {
struct inotify_event event; /* the user-space event */
@@ -109,20 +96,12 @@ struct inotify_kernel_event {
};
/*
- * struct inotify_watch - represents a watch request on a specific inode
- *
- * d_list is protected by dev->mutex of the associated watch->dev.
- * i_list and mask are protected by inode->inotify_mutex of the associated inode.
- * dev, inode, and wd are never written to once the watch is created.
+ * struct inotify_user_watch - our version of an inotify_watch, we add
+ * a reference to the associated inotify_device.
*/
-struct inotify_watch {
- struct list_head d_list; /* entry in inotify_device's list */
- struct list_head i_list; /* entry in inode's list */
- atomic_t count; /* reference count */
+struct inotify_user_watch {
struct inotify_device *dev; /* associated device */
- struct inode *inode; /* associated inode */
- s32 wd; /* watch descriptor */
- u32 mask; /* event mask for this watch */
+ struct inotify_watch wdata; /* inotify watch data */
};
#ifdef CONFIG_SYSCTL
@@ -150,16 +129,16 @@ ctl_table inotify_table[] = {
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
.strategy = &sysctl_intvec,
- .extra1 = &zero,
+ .extra1 = &zero,
},
{
.ctl_name = INOTIFY_MAX_QUEUED_EVENTS,
.procname = "max_queued_events",
.data = &inotify_max_queued_events,
.maxlen = sizeof(int),
- .mode = 0644,
+ .mode = 0644,
.proc_handler = &proc_dointvec_minmax,
- .strategy = &sysctl_intvec,
+ .strategy = &sysctl_intvec,
.extra1 = &zero
},
{ .ctl_name = 0 }
@@ -176,27 +155,20 @@ static inline void put_inotify_dev(struc
if (atomic_dec_and_test(&dev->count)) {
atomic_dec(&dev->user->inotify_devs);
free_uid(dev->user);
- idr_destroy(&dev->idr);
kfree(dev);
}
}
-static inline void get_inotify_watch(struct inotify_watch *watch)
-{
- atomic_inc(&watch->count);
-}
-
/*
- * put_inotify_watch - decrements the ref count on a given watch. cleans up
- * the watch and its references if the count reaches zero.
+ * free_inotify_user_watch - * cleans up the watch and its references
*/
-static inline void put_inotify_watch(struct inotify_watch *watch)
+static inline void free_inotify_user_watch(struct inotify_user_watch *watch)
{
- if (atomic_dec_and_test(&watch->count)) {
- put_inotify_dev(watch->dev);
- iput(watch->inode);
- kmem_cache_free(watch_cachep, watch);
- }
+ struct inotify_device *dev = watch->dev;
+
+ atomic_dec(&dev->user->inotify_watches);
+ put_inotify_dev(dev);
+ kmem_cache_free(watch_cachep, watch);
}
/*
@@ -247,7 +219,7 @@ static struct inotify_kernel_event * ker
}
memcpy(kevent->name, name, len);
if (rem)
- memset(kevent->name + len, 0, rem);
+ memset(kevent->name + len, 0, rem);
kevent->event.len = len + rem;
} else {
kevent->event.len = 0;
@@ -260,7 +232,7 @@ static struct inotify_kernel_event * ker
/*
* inotify_dev_get_event - return the next event in the given dev's queue
*
- * Caller must hold dev->mutex.
+ * Caller must hold dev->ev_mutex.
*/
static inline struct inotify_kernel_event *
inotify_dev_get_event(struct inotify_device *dev)
@@ -269,19 +241,33 @@ inotify_dev_get_event(struct inotify_dev
}
/*
- * inotify_dev_queue_event - add a new event to the given device
+ * inotify_dev_queue_event - event callback registered with core inotify, adds
+ * a new event to the given device
*
- * Caller must hold dev->mutex. Can sleep (calls kernel_event()).
+ * Can sleep (calls kernel_event()).
*/
-static void inotify_dev_queue_event(struct inotify_device *dev,
- struct inotify_watch *watch, u32 mask,
- u32 cookie, const char *name)
+static void inotify_dev_queue_event(struct inotify_watch *w, u32 wd, u32 mask,
+ u32 cookie, const char *name,
+ struct inode *ignored)
{
+ struct inotify_user_watch *watch;
+ struct inotify_device *dev;
struct inotify_kernel_event *kevent, *last;
+ watch = container_of(w, struct inotify_user_watch, wdata);
+ dev = watch->dev;
+
+ mutex_lock(&dev->ev_mutex);
+
+ /* we can safely put the watch as we don't reference it while
+ * generating the event
+ */
+ if (mask & IN_IGNORED)
+ free_inotify_user_watch(watch);
+
/* coalescing: drop this event if it is a dupe of the previous */
last = inotify_dev_get_event(dev);
- if (last && last->event.mask == mask && last->event.wd == watch->wd &&
+ if (last && last->event.mask == mask && last->event.wd == wd &&
last->event.cookie == cookie) {
const char *lastname = last->name;
@@ -299,7 +285,7 @@ static void inotify_dev_queue_event(stru
if (unlikely(dev->event_count == dev->max_events))
kevent = kernel_event(-1, IN_Q_OVERFLOW, cookie, NULL);
else
- kevent = kernel_event(watch->wd, mask, cookie, name);
+ kevent = kernel_event(wd, mask, cookie, name);
if (unlikely(!kevent))
return;
@@ -309,12 +295,14 @@ static void inotify_dev_queue_event(stru
dev->queue_size += sizeof(struct inotify_event) + kevent->event.len;
list_add_tail(&kevent->list, &dev->events);
wake_up_interruptible(&dev->wq);
+
+ mutex_unlock(&dev->ev_mutex);
}
/*
* remove_kevent - cleans up and ultimately frees the given kevent
*
- * Caller must hold dev->mutex.
+ * Caller must hold dev->ev_mutex.
*/
static void remove_kevent(struct inotify_device *dev,
struct inotify_kernel_event *kevent)
@@ -331,7 +319,7 @@ static void remove_kevent(struct inotify
/*
* inotify_dev_event_dequeue - destroy an event on the given device
*
- * Caller must hold dev->mutex.
+ * Caller must hold dev->ev_mutex.
*/
static void inotify_dev_event_dequeue(struct inotify_device *dev)
{
@@ -343,25 +331,6 @@ static void inotify_dev_event_dequeue(st
}
/*
- * inotify_dev_get_wd - returns the next WD for use by the given dev
- *
- * Callers must hold dev->mutex. This function can sleep.
- */
-static int inotify_dev_get_wd(struct inotify_device *dev,
- struct inotify_watch *watch)
-{
- int ret;
-
- do {
- if (unlikely(!idr_pre_get(&dev->idr, GFP_KERNEL)))
- return -ENOSPC;
- ret = idr_get_new_above(&dev->idr, watch, dev->last_wd+1, &watch->wd);
- } while (ret == -EAGAIN);
-
- return ret;
-}
-
-/*
* find_inode - resolve a user-given path to a specific inode and return a nd
*/
static int find_inode(const char __user *dirname, struct nameidata *nd,
@@ -374,359 +343,45 @@ static int find_inode(const char __user
return error;
/* you can only watch an inode if you have read permissions on it */
error = vfs_permission(nd, MAY_READ);
- if (error)
+ if (error)
path_release(nd);
return error;
}
/*
- * 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) {
- WARN_ON(child->d_flags & DCACHE_INOTIFY_PARENT_WATCHED);
- continue;
- }
- spin_lock(&child->d_lock);
- if (watched) {
- WARN_ON(child->d_flags &
- DCACHE_INOTIFY_PARENT_WATCHED);
- child->d_flags |= DCACHE_INOTIFY_PARENT_WATCHED;
- } else {
- WARN_ON(!(child->d_flags &
- DCACHE_INOTIFY_PARENT_WATCHED));
- child->d_flags&=~DCACHE_INOTIFY_PARENT_WATCHED;
- }
- spin_unlock(&child->d_lock);
- }
- }
- spin_unlock(&dcache_lock);
-}
-
-/*
* create_watch - creates a watch on the given device.
*
- * Callers must hold dev->mutex. Calls inotify_dev_get_wd() so may sleep.
- * Both 'dev' and 'inode' (by way of nameidata) need to be pinned.
+ * Callers must hold dev->up_mutex.
*/
-static struct inotify_watch *create_watch(struct inotify_device *dev,
- u32 mask, struct inode *inode)
+static int create_watch(struct inotify_device *dev, struct inode *inode,
+ u32 mask)
{
- struct inotify_watch *watch;
+ struct inotify_user_watch *watch;
int ret;
if (atomic_read(&dev->user->inotify_watches) >=
inotify_max_user_watches)
- return ERR_PTR(-ENOSPC);
+ return -ENOSPC;
watch = kmem_cache_alloc(watch_cachep, GFP_KERNEL);
if (unlikely(!watch))
- return ERR_PTR(-ENOMEM);
-
- ret = inotify_dev_get_wd(dev, watch);
- if (unlikely(ret)) {
- kmem_cache_free(watch_cachep, watch);
- return ERR_PTR(ret);
- }
-
- dev->last_wd = watch->wd;
- watch->mask = mask;
- atomic_set(&watch->count, 0);
- INIT_LIST_HEAD(&watch->d_list);
- INIT_LIST_HEAD(&watch->i_list);
+ return -ENOMEM;
/* save a reference to device and bump the count to make it official */
get_inotify_dev(dev);
watch->dev = dev;
- /*
- * 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);
-
- /* bump our own count, corresponding to our entry in dev->watches */
- get_inotify_watch(watch);
-
atomic_inc(&dev->user->inotify_watches);
- return watch;
-}
-
-/*
- * inotify_find_dev - find the watch associated with the given inode and dev
- *
- * Callers must hold inode->inotify_mutex.
- */
-static struct inotify_watch *inode_find_dev(struct inode *inode,
- struct inotify_device *dev)
-{
- struct inotify_watch *watch;
-
- list_for_each_entry(watch, &inode->inotify_watches, i_list) {
- if (watch->dev == dev)
- return watch;
- }
-
- return NULL;
-}
-
-/*
- * remove_watch_no_event - remove_watch() without the IN_IGNORED event.
- */
-static void remove_watch_no_event(struct inotify_watch *watch,
- struct inotify_device *dev)
-{
- list_del(&watch->i_list);
- list_del(&watch->d_list);
-
- if (!inotify_inode_watched(watch->inode))
- set_dentry_child_flags(watch->inode, 0);
+ ret = inotify_add_watch(dev->ih, &watch->wdata, inode, mask);
+ if (ret < 0)
+ free_inotify_user_watch(watch);
- atomic_dec(&dev->user->inotify_watches);
- idr_remove(&dev->idr, watch->wd);
- put_inotify_watch(watch);
-}
-
-/*
- * remove_watch - Remove a watch from both the device and the inode. Sends
- * the IN_IGNORED event to the given device signifying that the inode is no
- * longer watched.
- *
- * Callers must hold both inode->inotify_mutex and dev->mutex. We drop a
- * reference to the inode before returning.
- *
- * The inode is not iput() so as to remain atomic. If the inode needs to be
- * iput(), the call returns one. Otherwise, it returns zero.
- */
-static void remove_watch(struct inotify_watch *watch,struct inotify_device *dev)
-{
- inotify_dev_queue_event(dev, watch, IN_IGNORED, 0, NULL);
- remove_watch_no_event(watch, dev);
+ return ret;
}
/* Kernel API */
-/*
- * inotify_d_instantiate - instantiate dcache entry for inode
- */
-void inotify_d_instantiate(struct dentry *entry, struct inode *inode)
-{
- struct dentry *parent;
-
- if (!inode)
- return;
-
- WARN_ON(entry->d_flags & DCACHE_INOTIFY_PARENT_WATCHED);
- spin_lock(&entry->d_lock);
- parent = entry->d_parent;
- if (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
- */
-void inotify_inode_queue_event(struct inode *inode, u32 mask, u32 cookie,
- const char *name)
-{
- 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_device *dev = watch->dev;
- get_inotify_watch(watch);
- mutex_lock(&dev->mutex);
- inotify_dev_queue_event(dev, watch, mask, cookie, name);
- if (watch_mask & IN_ONESHOT)
- remove_watch_no_event(watch, dev);
- mutex_unlock(&dev->mutex);
- put_inotify_watch(watch);
- }
- }
- 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);
- 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;
-
- /*
- * 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;
-
- /*
- * We cannot __iget() an inode in state I_CLEAR, I_FREEING, or
- * I_WILL_FREE 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))
- continue;
-
- need_iput_tmp = need_iput;
- need_iput = NULL;
- /* In case the remove_watch() 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_device *dev = watch->dev;
- mutex_lock(&dev->mutex);
- inotify_dev_queue_event(dev, watch, IN_UNMOUNT,0,NULL);
- remove_watch(watch, dev);
- mutex_unlock(&dev->mutex);
- }
- 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_device *dev = watch->dev;
- mutex_lock(&dev->mutex);
- remove_watch(watch, dev);
- mutex_unlock(&dev->mutex);
- }
- mutex_unlock(&inode->inotify_mutex);
-}
-EXPORT_SYMBOL_GPL(inotify_inode_is_dead);
-
/* Device Interface */
static unsigned int inotify_poll(struct file *file, poll_table *wait)
@@ -735,10 +390,10 @@ static unsigned int inotify_poll(struct
int ret = 0;
poll_wait(file, &dev->wq, wait);
- mutex_lock(&dev->mutex);
+ mutex_lock(&dev->ev_mutex);
if (!list_empty(&dev->events))
ret = POLLIN | POLLRDNORM;
- mutex_unlock(&dev->mutex);
+ mutex_unlock(&dev->ev_mutex);
return ret;
}
@@ -760,9 +415,9 @@ static ssize_t inotify_read(struct file
prepare_to_wait(&dev->wq, &wait, TASK_INTERRUPTIBLE);
- mutex_lock(&dev->mutex);
+ mutex_lock(&dev->ev_mutex);
events = !list_empty(&dev->events);
- mutex_unlock(&dev->mutex);
+ mutex_unlock(&dev->ev_mutex);
if (events) {
ret = 0;
break;
@@ -785,7 +440,7 @@ static ssize_t inotify_read(struct file
if (ret)
return ret;
- mutex_lock(&dev->mutex);
+ mutex_lock(&dev->ev_mutex);
while (1) {
struct inotify_kernel_event *kevent;
@@ -815,7 +470,7 @@ static ssize_t inotify_read(struct file
remove_kevent(dev, kevent);
}
- mutex_unlock(&dev->mutex);
+ mutex_unlock(&dev->ev_mutex);
return ret;
}
@@ -824,41 +479,13 @@ static int inotify_release(struct inode
{
struct inotify_device *dev = file->private_data;
- /*
- * Destroy all of the watches on this device. 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 dev->mutex. The following works.
- */
- while (1) {
- struct inotify_watch *watch;
- struct list_head *watches;
- struct inode *inode;
-
- mutex_lock(&dev->mutex);
- watches = &dev->watches;
- if (list_empty(watches)) {
- mutex_unlock(&dev->mutex);
- break;
- }
- watch = list_entry(watches->next, struct inotify_watch, d_list);
- get_inotify_watch(watch);
- mutex_unlock(&dev->mutex);
-
- inode = watch->inode;
- mutex_lock(&inode->inotify_mutex);
- mutex_lock(&dev->mutex);
- remove_watch_no_event(watch, dev);
- mutex_unlock(&dev->mutex);
- mutex_unlock(&inode->inotify_mutex);
- put_inotify_watch(watch);
- }
+ inotify_destroy(dev->ih);
/* destroy all of the events on this device */
- mutex_lock(&dev->mutex);
+ mutex_lock(&dev->ev_mutex);
while (!list_empty(&dev->events))
inotify_dev_event_dequeue(dev);
- mutex_unlock(&dev->mutex);
+ mutex_unlock(&dev->ev_mutex);
/* free this device: the put matching the get in inotify_init() */
put_inotify_dev(dev);
@@ -866,41 +493,6 @@ static int inotify_release(struct inode
return 0;
}
-/*
- * inotify_ignore - remove a given wd from this inotify instance.
- *
- * Can sleep.
- */
-static int inotify_ignore(struct inotify_device *dev, s32 wd)
-{
- struct inotify_watch *watch;
- struct inode *inode;
-
- mutex_lock(&dev->mutex);
- watch = idr_find(&dev->idr, wd);
- if (unlikely(!watch)) {
- mutex_unlock(&dev->mutex);
- return -EINVAL;
- }
- get_inotify_watch(watch);
- inode = watch->inode;
- mutex_unlock(&dev->mutex);
-
- mutex_lock(&inode->inotify_mutex);
- mutex_lock(&dev->mutex);
-
- /* make sure that we did not race */
- watch = idr_find(&dev->idr, wd);
- if (likely(watch))
- remove_watch(watch, dev);
-
- mutex_unlock(&dev->mutex);
- mutex_unlock(&inode->inotify_mutex);
- put_inotify_watch(watch);
-
- return 0;
-}
-
static long inotify_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
@@ -931,8 +523,9 @@ static const struct file_operations inot
asmlinkage long sys_inotify_init(void)
{
struct inotify_device *dev;
+ struct inotify_handle *ih;
struct user_struct *user;
- struct file *filp;
+ struct file *filp;
int fd, ret;
fd = get_unused_fd();
@@ -958,6 +551,13 @@ asmlinkage long sys_inotify_init(void)
goto out_free_uid;
}
+ ih = inotify_init(inotify_dev_queue_event);
+ if (unlikely(IS_ERR(ih))) {
+ ret = PTR_ERR(ih);
+ goto out_free_dev;
+ }
+ dev->ih = ih;
+
filp->f_op = &inotify_fops;
filp->f_vfsmnt = mntget(inotify_mnt);
filp->f_dentry = dget(inotify_mnt->mnt_root);
@@ -966,16 +566,14 @@ asmlinkage long sys_inotify_init(void)
filp->f_flags = O_RDONLY;
filp->private_data = dev;
- idr_init(&dev->idr);
INIT_LIST_HEAD(&dev->events);
- INIT_LIST_HEAD(&dev->watches);
init_waitqueue_head(&dev->wq);
- mutex_init(&dev->mutex);
+ mutex_init(&dev->ev_mutex);
+ mutex_init(&dev->up_mutex);
dev->event_count = 0;
dev->queue_size = 0;
dev->max_events = inotify_max_queued_events;
dev->user = user;
- dev->last_wd = 0;
atomic_set(&dev->count, 0);
get_inotify_dev(dev);
@@ -983,6 +581,8 @@ asmlinkage long sys_inotify_init(void)
fd_install(fd, filp);
return fd;
+out_free_dev:
+ kfree(dev);
out_free_uid:
free_uid(user);
put_filp(filp);
@@ -993,13 +593,11 @@ out_put_fd:
asmlinkage long sys_inotify_add_watch(int fd, const char __user *path, u32 mask)
{
- struct inotify_watch *watch, *old;
struct inode *inode;
struct inotify_device *dev;
struct nameidata nd;
struct file *filp;
int ret, fput_needed;
- int mask_add = 0;
unsigned flags = 0;
filp = fget_light(fd, &fput_needed);
@@ -1025,49 +623,12 @@ asmlinkage long sys_inotify_add_watch(in
inode = nd.dentry->d_inode;
dev = filp->private_data;
- mutex_lock(&inode->inotify_mutex);
- mutex_lock(&dev->mutex);
-
- if (mask & IN_MASK_ADD)
- mask_add = 1;
+ mutex_lock(&dev->up_mutex);
+ ret = inotify_find_update_watch(dev->ih, inode, mask);
+ if (ret == -ENOENT)
+ ret = create_watch(dev, inode, mask);
+ mutex_unlock(&dev->up_mutex);
- /* don't let user-space set invalid bits: we don't want flags set */
- mask &= IN_ALL_EVENTS | IN_ONESHOT;
- if (unlikely(!mask)) {
- ret = -EINVAL;
- goto out;
- }
-
- /*
- * Handle the case of re-adding a watch on an (inode,dev) pair that we
- * are already watching. We just update the mask and return its wd.
- */
- old = inode_find_dev(inode, dev);
- if (unlikely(old)) {
- if (mask_add)
- old->mask |= mask;
- else
- old->mask = mask;
- ret = old->wd;
- goto out;
- }
-
- watch = create_watch(dev, mask, inode);
- if (unlikely(IS_ERR(watch))) {
- ret = PTR_ERR(watch);
- goto out;
- }
-
- if (!inotify_inode_watched(inode))
- set_dentry_child_flags(inode, 1);
-
- /* Add the watch to the device's and the inode's list */
- list_add(&watch->d_list, &dev->watches);
- list_add(&watch->i_list, &inode->inotify_watches);
- ret = watch->wd;
-out:
- mutex_unlock(&dev->mutex);
- mutex_unlock(&inode->inotify_mutex);
path_release(&nd);
fput_and_out:
fput_light(filp, fput_needed);
@@ -1091,7 +652,9 @@ asmlinkage long sys_inotify_rm_watch(int
}
dev = filp->private_data;
- ret = inotify_ignore(dev, wd);
+
+ /* we free our watch data when we get IN_IGNORED */
+ ret = inotify_rm_wd(dev->ih, wd);
out:
fput_light(filp, fput_needed);
@@ -1112,11 +675,11 @@ static struct file_system_type inotify_f
};
/*
- * inotify_setup - Our initialization function. Note that we cannnot return
+ * inotify_user_setup - Our initialization function. Note that we cannnot return
* error because we have compiled-in VFS hooks. So an (unlikely) failure here
* must result in panic().
*/
-static int __init inotify_setup(void)
+static int __init inotify_user_setup(void)
{
int ret;
@@ -1132,10 +695,8 @@ static int __init inotify_setup(void)
inotify_max_user_instances = 128;
inotify_max_user_watches = 8192;
- atomic_set(&inotify_cookie, 0);
-
watch_cachep = kmem_cache_create("inotify_watch_cache",
- sizeof(struct inotify_watch),
+ sizeof(struct inotify_user_watch),
0, SLAB_PANIC, NULL, NULL);
event_cachep = kmem_cache_create("inotify_event_cache",
sizeof(struct inotify_kernel_event),
@@ -1144,4 +705,4 @@ static int __init inotify_setup(void)
return 0;
}
-module_init(inotify_setup);
+module_init(inotify_user_setup);
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