summaryrefslogtreecommitdiff
path: root/fs/notify/fsnotify.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/notify/fsnotify.c')
-rw-r--r--fs/notify/fsnotify.c141
1 files changed, 116 insertions, 25 deletions
diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index fcc2f064af83..9810babb1a3b 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -21,6 +21,7 @@
#include <linux/gfp.h>
#include <linux/init.h>
#include <linux/module.h>
+#include <linux/mount.h>
#include <linux/srcu.h>
#include <linux/fsnotify_backend.h>
@@ -35,6 +36,11 @@ void __fsnotify_inode_delete(struct inode *inode)
}
EXPORT_SYMBOL_GPL(__fsnotify_inode_delete);
+void __fsnotify_vfsmount_delete(struct vfsmount *mnt)
+{
+ fsnotify_clear_marks_by_mount(mnt);
+}
+
/*
* Given an inode, first check if we care what happens to our children. Inotify
* and dnotify both tell their parents about events. If we care about any event
@@ -78,13 +84,16 @@ void __fsnotify_update_child_dentry_flags(struct inode *inode)
}
/* Notify this dentry's parent about a child's events. */
-void __fsnotify_parent(struct dentry *dentry, __u32 mask)
+void __fsnotify_parent(struct path *path, struct dentry *dentry, __u32 mask)
{
struct dentry *parent;
struct inode *p_inode;
bool send = false;
bool should_update_children = false;
+ if (!dentry)
+ dentry = path->dentry;
+
if (!(dentry->d_flags & DCACHE_FSNOTIFY_PARENT_WATCHED))
return;
@@ -115,8 +124,12 @@ void __fsnotify_parent(struct dentry *dentry, __u32 mask)
* specifies these are events which came from a child. */
mask |= FS_EVENT_ON_CHILD;
- fsnotify(p_inode, mask, dentry->d_inode, FSNOTIFY_EVENT_INODE,
- dentry->d_name.name, 0);
+ if (path)
+ fsnotify(p_inode, mask, path, FSNOTIFY_EVENT_PATH,
+ dentry->d_name.name, 0);
+ else
+ fsnotify(p_inode, mask, dentry->d_inode, FSNOTIFY_EVENT_INODE,
+ dentry->d_name.name, 0);
dput(parent);
}
@@ -127,51 +140,127 @@ void __fsnotify_parent(struct dentry *dentry, __u32 mask)
}
EXPORT_SYMBOL_GPL(__fsnotify_parent);
+void __fsnotify_flush_ignored_mask(struct inode *inode, void *data, int data_is)
+{
+ struct fsnotify_mark *mark;
+ struct hlist_node *node;
+
+ if (!hlist_empty(&inode->i_fsnotify_marks)) {
+ spin_lock(&inode->i_lock);
+ hlist_for_each_entry(mark, node, &inode->i_fsnotify_marks, i.i_list) {
+ if (!(mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY))
+ mark->ignored_mask = 0;
+ }
+ spin_unlock(&inode->i_lock);
+ }
+
+ if (data_is == FSNOTIFY_EVENT_PATH) {
+ struct vfsmount *mnt;
+
+ mnt = ((struct path *)data)->mnt;
+ if (mnt && !hlist_empty(&mnt->mnt_fsnotify_marks)) {
+ spin_lock(&mnt->mnt_root->d_lock);
+ hlist_for_each_entry(mark, node, &mnt->mnt_fsnotify_marks, m.m_list) {
+ if (!(mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY))
+ mark->ignored_mask = 0;
+ }
+ spin_unlock(&mnt->mnt_root->d_lock);
+ }
+ }
+}
+
+static int send_to_group(struct fsnotify_group *group, struct inode *to_tell,
+ struct vfsmount *mnt, __u32 mask, void *data,
+ int data_is, u32 cookie, const unsigned char *file_name,
+ struct fsnotify_event **event)
+{
+ if (!group->ops->should_send_event(group, to_tell, mnt, mask,
+ data, data_is))
+ return 0;
+ if (!*event) {
+ *event = fsnotify_create_event(to_tell, mask, data,
+ data_is, file_name,
+ cookie, GFP_KERNEL);
+ if (!*event)
+ return -ENOMEM;
+ }
+ return group->ops->handle_event(group, *event);
+}
+
+static bool needed_by_vfsmount(__u32 test_mask, struct vfsmount *mnt)
+{
+ if (!mnt)
+ return false;
+
+ return (test_mask & mnt->mnt_fsnotify_mask);
+}
+
/*
* This is the main call to fsnotify. The VFS calls into hook specific functions
* in linux/fsnotify.h. Those functions then in turn call here. Here will call
* out to all of the registered fsnotify_group. Those groups can then use the
* notification event in whatever means they feel necessary.
*/
-void fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, const char *file_name, u32 cookie)
+int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is,
+ const unsigned char *file_name, u32 cookie)
{
struct fsnotify_group *group;
struct fsnotify_event *event = NULL;
- int idx;
+ struct vfsmount *mnt = NULL;
+ int idx, ret = 0;
/* global tests shouldn't care about events on child only the specific event */
__u32 test_mask = (mask & ~FS_EVENT_ON_CHILD);
- if (list_empty(&fsnotify_groups))
- return;
+ /* if no fsnotify listeners, nothing to do */
+ if (list_empty(&fsnotify_inode_groups) &&
+ list_empty(&fsnotify_vfsmount_groups))
+ return 0;
+
+ if (mask & FS_MODIFY)
+ __fsnotify_flush_ignored_mask(to_tell, data, data_is);
- if (!(test_mask & fsnotify_mask))
- return;
+ /* if none of the directed listeners or vfsmount listeners care */
+ if (!(test_mask & fsnotify_inode_mask) &&
+ !(test_mask & fsnotify_vfsmount_mask))
+ return 0;
+
+ if (data_is == FSNOTIFY_EVENT_PATH)
+ mnt = ((struct path *)data)->mnt;
+
+ /* if this inode's directed listeners don't care and nothing on the vfsmount
+ * listeners list cares, nothing to do */
+ if (!(test_mask & to_tell->i_fsnotify_mask) &&
+ !needed_by_vfsmount(test_mask, mnt))
+ return 0;
- if (!(test_mask & to_tell->i_fsnotify_mask))
- return;
/*
* SRCU!! the groups list is very very much read only and the path is
* very hot. The VAST majority of events are not going to need to do
* anything other than walk the list so it's crazy to pre-allocate.
*/
idx = srcu_read_lock(&fsnotify_grp_srcu);
- list_for_each_entry_rcu(group, &fsnotify_groups, group_list) {
- if (test_mask & group->mask) {
- if (!group->ops->should_send_event(group, to_tell, mask))
- continue;
- if (!event) {
- event = fsnotify_create_event(to_tell, mask, data,
- data_is, file_name, cookie,
- GFP_KERNEL);
- /* shit, we OOM'd and now we can't tell, maybe
- * someday someone else will want to do something
- * here */
- if (!event)
- break;
+
+ if (test_mask & to_tell->i_fsnotify_mask) {
+ list_for_each_entry_rcu(group, &fsnotify_inode_groups, inode_group_list) {
+ if (test_mask & group->mask) {
+ ret = send_to_group(group, to_tell, NULL, mask, data, data_is,
+ cookie, file_name, &event);
+ if (ret)
+ goto out;
}
- group->ops->handle_event(group, event);
}
}
+ if (needed_by_vfsmount(test_mask, mnt)) {
+ list_for_each_entry_rcu(group, &fsnotify_vfsmount_groups, vfsmount_group_list) {
+ if (test_mask & group->mask) {
+ ret = send_to_group(group, to_tell, mnt, mask, data, data_is,
+ cookie, file_name, &event);
+ if (ret)
+ goto out;
+ }
+ }
+ }
+out:
srcu_read_unlock(&fsnotify_grp_srcu, idx);
/*
* fsnotify_create_event() took a reference so the event can't be cleaned
@@ -179,6 +268,8 @@ void fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, const
*/
if (event)
fsnotify_put_event(event);
+
+ return ret;
}
EXPORT_SYMBOL_GPL(fsnotify);