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Diffstat (limited to 'fs/notify/inotify/inotify_user.c')
-rw-r--r--fs/notify/inotify/inotify_user.c269
1 files changed, 103 insertions, 166 deletions
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 444c305a468..cc423a30a0c 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -40,6 +40,7 @@
#include <linux/wait.h>
#include "inotify.h"
+#include "../fdinfo.h"
#include <asm/ioctls.h>
@@ -49,7 +50,6 @@ static int inotify_max_queued_events __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;
#ifdef CONFIG_SYSCTL
@@ -57,7 +57,7 @@ struct kmem_cache *event_priv_cachep __read_mostly;
static int zero;
-ctl_table inotify_table[] = {
+struct ctl_table inotify_table[] = {
{
.procname = "max_user_instances",
.data = &inotify_max_user_instances,
@@ -123,6 +123,16 @@ static unsigned int inotify_poll(struct file *file, poll_table *wait)
return ret;
}
+static int round_event_name_len(struct fsnotify_event *fsn_event)
+{
+ struct inotify_event_info *event;
+
+ event = INOTIFY_E(fsn_event);
+ if (!event->name_len)
+ return 0;
+ return roundup(event->name_len + 1, sizeof(struct inotify_event));
+}
+
/*
* Get an inotify_kernel_event if one exists and is small
* enough to fit in "count". Return an error pointer if
@@ -143,9 +153,7 @@ static struct fsnotify_event *get_one_event(struct fsnotify_group *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);
-
+ event_size += round_event_name_len(event);
if (event_size > count)
return ERR_PTR(-EINVAL);
@@ -163,40 +171,27 @@ static struct fsnotify_event *get_one_event(struct fsnotify_group *group,
* buffer we had in "get_one_event()" above.
*/
static ssize_t copy_event_to_user(struct fsnotify_group *group,
- struct fsnotify_event *event,
+ struct fsnotify_event *fsn_event,
char __user *buf)
{
struct inotify_event inotify_event;
- struct fsnotify_event_private_data *fsn_priv;
- struct inotify_event_private_data *priv;
+ struct inotify_event_info *event;
size_t event_size = sizeof(struct inotify_event);
- size_t name_len = 0;
+ size_t name_len;
+ size_t pad_name_len;
- 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);
- spin_unlock(&event->lock);
-
- if (!fsn_priv)
- inotify_event.wd = -1;
- else {
- priv = container_of(fsn_priv, struct inotify_event_private_data,
- fsnotify_event_priv_data);
- inotify_event.wd = priv->wd;
- inotify_free_event_priv(fsn_priv);
- }
+ pr_debug("%s: group=%p event=%p\n", __func__, group, fsn_event);
+ event = INOTIFY_E(fsn_event);
+ name_len = event->name_len;
/*
- * round up event->name_len so it is a multiple of event_size
+ * round up name length so it is a multiple of event_size
* plus an extra byte for the terminating '\0'.
*/
- if (event->name_len)
- name_len = roundup(event->name_len + 1, event_size);
- inotify_event.len = name_len;
-
- inotify_event.mask = inotify_mask_to_arg(event->mask);
+ pad_name_len = round_event_name_len(fsn_event);
+ inotify_event.len = pad_name_len;
+ inotify_event.mask = inotify_mask_to_arg(fsn_event->mask);
+ inotify_event.wd = event->wd;
inotify_event.cookie = event->sync_cookie;
/* send the main event */
@@ -208,20 +203,18 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group,
/*
* fsnotify only stores the pathname, so here we have to send the pathname
* and then pad that pathname out to a multiple of sizeof(inotify_event)
- * with zeros. I get my zeros from the nul_inotify_event.
+ * with zeros.
*/
- if (name_len) {
- unsigned int len_to_zero = name_len - event->name_len;
+ if (pad_name_len) {
/* copy the path name */
- if (copy_to_user(buf, event->file_name, event->name_len))
+ if (copy_to_user(buf, event->name, name_len))
return -EFAULT;
- buf += event->name_len;
+ buf += name_len;
/* fill userspace with 0's */
- if (clear_user(buf, len_to_zero))
+ if (clear_user(buf, pad_name_len - name_len))
return -EFAULT;
- buf += len_to_zero;
- event_size += name_len;
+ event_size += pad_name_len;
}
return event_size;
@@ -253,7 +246,7 @@ static ssize_t inotify_read(struct file *file, char __user *buf,
if (IS_ERR(kevent))
break;
ret = copy_event_to_user(group, kevent, buf);
- fsnotify_put_event(kevent);
+ fsnotify_destroy_event(group, kevent);
if (ret < 0)
break;
buf += ret;
@@ -264,7 +257,7 @@ static ssize_t inotify_read(struct file *file, char __user *buf,
ret = -EAGAIN;
if (file->f_flags & O_NONBLOCK)
break;
- ret = -EINTR;
+ ret = -ERESTARTSYS;
if (signal_pending(current))
break;
@@ -280,26 +273,14 @@ static ssize_t inotify_read(struct file *file, char __user *buf,
return ret;
}
-static int inotify_fasync(int fd, struct file *file, int on)
-{
- struct fsnotify_group *group = file->private_data;
-
- return fasync_helper(fd, file, on, &group->inotify_data.fa) >= 0 ? 0 : -EIO;
-}
-
static int inotify_release(struct inode *ignored, struct file *file)
{
struct fsnotify_group *group = file->private_data;
- 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 */
- fsnotify_put_group(group);
-
- atomic_dec(&user->inotify_devs);
+ fsnotify_destroy_group(group);
return 0;
}
@@ -308,8 +289,7 @@ static long inotify_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
struct fsnotify_group *group;
- struct fsnotify_event_holder *holder;
- struct fsnotify_event *event;
+ struct fsnotify_event *fsn_event;
void __user *p;
int ret = -ENOTTY;
size_t send_len = 0;
@@ -322,12 +302,10 @@ static long inotify_ioctl(struct file *file, unsigned int cmd,
switch (cmd) {
case FIONREAD:
mutex_lock(&group->notification_mutex);
- list_for_each_entry(holder, &group->notification_list, event_list) {
- event = holder->event;
+ list_for_each_entry(fsn_event, &group->notification_list,
+ list) {
send_len += sizeof(struct inotify_event);
- if (event->name_len)
- send_len += roundup(event->name_len + 1,
- sizeof(struct inotify_event));
+ send_len += round_event_name_len(fsn_event);
}
mutex_unlock(&group->notification_mutex);
ret = put_user(send_len, (int __user *) p);
@@ -338,9 +316,10 @@ static long inotify_ioctl(struct file *file, unsigned int cmd,
}
static const struct file_operations inotify_fops = {
+ .show_fdinfo = inotify_show_fdinfo,
.poll = inotify_poll,
.read = inotify_read,
- .fasync = inotify_fasync,
+ .fasync = fsnotify_fasync,
.release = inotify_release,
.unlocked_ioctl = inotify_ioctl,
.compat_ioctl = inotify_ioctl,
@@ -366,27 +345,23 @@ static int inotify_find_inode(const char __user *dirname, struct path *path, uns
}
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;
+ idr_preload(GFP_KERNEL);
+ spin_lock(idr_lock);
- spin_lock(idr_lock);
- ret = idr_get_new_above(idr, i_mark, *last_wd + 1,
- &i_mark->wd);
+ ret = idr_alloc_cyclic(idr, i_mark, 1, 0, GFP_NOWAIT);
+ if (ret >= 0) {
/* 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);
+ i_mark->wd = ret;
+ fsnotify_get_mark(&i_mark->fsn_mark);
+ }
- return ret;
+ spin_unlock(idr_lock);
+ idr_preload_end();
+ return ret < 0 ? ret : 0;
}
static struct inotify_inode_mark *inotify_idr_find_locked(struct fsnotify_group *group,
@@ -517,42 +492,12 @@ void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark,
struct fsnotify_group *group)
{
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;
- ignored_event = fsnotify_create_event(NULL, FS_IN_IGNORED, NULL,
- FSNOTIFY_EVENT_NONE, NULL, 0,
- GFP_NOFS);
- if (!ignored_event)
- return;
+ /* Queue ignore event for the watch */
+ inotify_handle_event(group, NULL, fsn_mark, NULL, FS_IN_IGNORED,
+ NULL, FSNOTIFY_EVENT_NONE, NULL, 0);
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))
- goto skip_send_ignore;
-
- fsn_event_priv = &event_priv->fsnotify_event_priv_data;
-
- fsn_event_priv->group = group;
- 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 mark from the idr */
inotify_remove_from_idr(group, i_mark);
@@ -580,10 +525,7 @@ static int inotify_update_existing_watch(struct fsnotify_group *group,
int add = (arg & IN_MASK_ADD);
int ret;
- /* don't allow invalid bits: we don't want flags set */
mask = inotify_arg_to_mask(arg);
- if (unlikely(!(mask & IN_ALL_EVENTS)))
- return -EINVAL;
fsn_mark = fsnotify_find_inode_mark(group, inode);
if (!fsn_mark)
@@ -633,10 +575,7 @@ static int inotify_new_watch(struct fsnotify_group *group,
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 & IN_ALL_EVENTS)))
- return -EINVAL;
tmp_i_mark = kmem_cache_alloc(inotify_inode_mark_cachep, GFP_KERNEL);
if (unlikely(!tmp_i_mark))
@@ -650,13 +589,13 @@ static int inotify_new_watch(struct fsnotify_group *group,
if (atomic_read(&group->inotify_data.user->inotify_watches) >= inotify_max_user_watches)
goto out_err;
- ret = inotify_add_to_idr(idr, idr_lock, &group->inotify_data.last_wd,
- tmp_i_mark);
+ ret = inotify_add_to_idr(idr, idr_lock, tmp_i_mark);
if (ret)
goto out_err;
/* we are on the idr, now get on the inode */
- ret = fsnotify_add_mark(&tmp_i_mark->fsn_mark, group, inode, NULL, 0);
+ ret = fsnotify_add_mark_locked(&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_i_mark);
@@ -680,38 +619,48 @@ static int inotify_update_watch(struct fsnotify_group *group, struct inode *inod
{
int ret = 0;
-retry:
+ mutex_lock(&group->mark_mutex);
/* try to update and existing watch with the new arg */
ret = inotify_update_existing_watch(group, inode, arg);
/* no mark present, try to add a new one */
if (ret == -ENOENT)
ret = inotify_new_watch(group, inode, arg);
- /*
- * inotify_new_watch could race with another thread which did an
- * inotify_new_watch between the update_existing and the add watch
- * here, go back and try to update an existing mark again.
- */
- if (ret == -EEXIST)
- goto retry;
+ mutex_unlock(&group->mark_mutex);
return ret;
}
-static struct fsnotify_group *inotify_new_group(struct user_struct *user, unsigned int max_events)
+static struct fsnotify_group *inotify_new_group(unsigned int max_events)
{
struct fsnotify_group *group;
+ struct inotify_event_info *oevent;
group = fsnotify_alloc_group(&inotify_fsnotify_ops);
if (IS_ERR(group))
return group;
+ oevent = kmalloc(sizeof(struct inotify_event_info), GFP_KERNEL);
+ if (unlikely(!oevent)) {
+ fsnotify_destroy_group(group);
+ return ERR_PTR(-ENOMEM);
+ }
+ group->overflow_event = &oevent->fse;
+ fsnotify_init_event(group->overflow_event, NULL, FS_Q_OVERFLOW);
+ oevent->wd = -1;
+ oevent->sync_cookie = 0;
+ oevent->name_len = 0;
+
group->max_events = max_events;
spin_lock_init(&group->inotify_data.idr_lock);
idr_init(&group->inotify_data.idr);
- group->inotify_data.last_wd = 0;
- group->inotify_data.user = user;
- group->inotify_data.fa = NULL;
+ group->inotify_data.user = get_current_user();
+
+ if (atomic_inc_return(&group->inotify_data.user->inotify_devs) >
+ inotify_max_user_instances) {
+ fsnotify_destroy_group(group);
+ return ERR_PTR(-EMFILE);
+ }
return group;
}
@@ -721,7 +670,6 @@ static struct fsnotify_group *inotify_new_group(struct user_struct *user, unsign
SYSCALL_DEFINE1(inotify_init1, int, flags)
{
struct fsnotify_group *group;
- struct user_struct *user;
int ret;
/* Check the IN_* constants for consistency. */
@@ -731,30 +679,16 @@ SYSCALL_DEFINE1(inotify_init1, int, flags)
if (flags & ~(IN_CLOEXEC | IN_NONBLOCK))
return -EINVAL;
- user = get_current_user();
- if (unlikely(atomic_read(&user->inotify_devs) >=
- inotify_max_user_instances)) {
- ret = -EMFILE;
- goto out_free_uid;
- }
-
/* fsnotify_obtain_group took a reference to group, we put this when we kill the file in the end */
- group = inotify_new_group(user, inotify_max_queued_events);
- if (IS_ERR(group)) {
- ret = PTR_ERR(group);
- goto out_free_uid;
- }
-
- atomic_inc(&user->inotify_devs);
+ group = inotify_new_group(inotify_max_queued_events);
+ if (IS_ERR(group))
+ return PTR_ERR(group);
ret = anon_inode_getfd("inotify", &inotify_fops, group,
O_RDONLY | flags);
- if (ret >= 0)
- return ret;
+ if (ret < 0)
+ fsnotify_destroy_group(group);
- atomic_dec(&user->inotify_devs);
-out_free_uid:
- free_uid(user);
return ret;
}
@@ -769,16 +703,20 @@ SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname,
struct fsnotify_group *group;
struct inode *inode;
struct path path;
- struct file *filp;
- int ret, fput_needed;
+ struct fd f;
+ int ret;
unsigned flags = 0;
- filp = fget_light(fd, &fput_needed);
- if (unlikely(!filp))
+ /* don't allow invalid bits: we don't want flags set */
+ if (unlikely(!(mask & ALL_INOTIFY_BITS)))
+ return -EINVAL;
+
+ f = fdget(fd);
+ if (unlikely(!f.file))
return -EBADF;
/* verify that this is indeed an inotify instance */
- if (unlikely(filp->f_op != &inotify_fops)) {
+ if (unlikely(f.file->f_op != &inotify_fops)) {
ret = -EINVAL;
goto fput_and_out;
}
@@ -794,13 +732,13 @@ SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname,
/* inode held in place by reference to path; group by fget on fd */
inode = path.dentry->d_inode;
- group = filp->private_data;
+ group = f.file->private_data;
/* create/update an inode mark */
ret = inotify_update_watch(group, inode, mask);
path_put(&path);
fput_and_out:
- fput_light(filp, fput_needed);
+ fdput(f);
return ret;
}
@@ -808,19 +746,19 @@ SYSCALL_DEFINE2(inotify_rm_watch, int, fd, __s32, wd)
{
struct fsnotify_group *group;
struct inotify_inode_mark *i_mark;
- struct file *filp;
- int ret = 0, fput_needed;
+ struct fd f;
+ int ret = 0;
- filp = fget_light(fd, &fput_needed);
- if (unlikely(!filp))
+ f = fdget(fd);
+ if (unlikely(!f.file))
return -EBADF;
/* verify that this is indeed an inotify instance */
ret = -EINVAL;
- if (unlikely(filp->f_op != &inotify_fops))
+ if (unlikely(f.file->f_op != &inotify_fops))
goto out;
- group = filp->private_data;
+ group = f.file->private_data;
ret = -EINVAL;
i_mark = inotify_idr_find(group, wd);
@@ -829,18 +767,18 @@ SYSCALL_DEFINE2(inotify_rm_watch, int, fd, __s32, wd)
ret = 0;
- fsnotify_destroy_mark(&i_mark->fsn_mark);
+ fsnotify_destroy_mark(&i_mark->fsn_mark, group);
/* match ref taken by inotify_idr_find */
fsnotify_put_mark(&i_mark->fsn_mark);
out:
- fput_light(filp, fput_needed);
+ fdput(f);
return ret;
}
/*
- * inotify_user_setup - Our initialization function. Note that we cannnot return
+ * inotify_user_setup - Our initialization function. Note that we cannot return
* error because we have compiled-in VFS hooks. So an (unlikely) failure here
* must result in panic().
*/
@@ -868,7 +806,6 @@ static int __init inotify_user_setup(void)
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;
inotify_max_user_instances = 128;