fsnotify: Infrastructure for per-mount watches

Per-mount watches allow groups to listen to fsnotify events on an entire
mount.  This patch simply adds and initializes the fields needed in the
vfsmount struct to make this happen.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>

diff --git a/fs/namespace.c b/fs/namespace.c
index a2d681a6b5e9b01b494deefe6471463e8e699357..1969d6b2571eb3267b38f29412bff86179883edd 100644 (file)
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -614,6 +614,7 @@ static inline void __mntput(struct vfsmount *mnt)
         * provides barriers, so count_mnt_writers() below is safe.  AV
         */
        WARN_ON(count_mnt_writers(mnt));
+       fsnotify_vfsmount_delete(mnt);
        dput(mnt->mnt_root);
        free_vfsmnt(mnt);
        deactivate_super(sb);

diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index e0bf86953e1b8d20f9ed4c22475ea4fed9a7a1c5..7f14ddc3efc2249a6ab3c475e1fbedc63b39a993 100644 (file)
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -36,6 +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

diff --git a/fs/notify/fsnotify.h b/fs/notify/fsnotify.h
index 38f3fb5cef28bfadd942b7c7518de175bd5905b0..204353c0f663957899d275e290aca242f0c0563d 100644 (file)
--- a/fs/notify/fsnotify.h
+++ b/fs/notify/fsnotify.h
@@ -42,6 +42,8 @@ extern void fsnotify_destroy_vfsmount_mark(struct fsnotify_mark *mark);
 extern void fsnotify_destroy_inode_mark(struct fsnotify_mark *mark);
 /* run the list of all marks associated with inode and flag them to be freed */
 extern void fsnotify_clear_marks_by_inode(struct inode *inode);
+/* run the list of all marks associated with vfsmount and flag them to be freed */
+extern void fsnotify_clear_marks_by_mount(struct vfsmount *mnt);
 /*
  * update the dentry->d_flags of all of inode's children to indicate if inode cares
  * about events that happen to its children.

diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h
index 5184a2b786c1e817cf3432354056f6298773f9dd..06c0e50c7968046347917b7997b5b4406e26b00a 100644 (file)
--- a/include/linux/fsnotify.h
+++ b/include/linux/fsnotify.h
@@ -95,6 +95,14 @@ static inline void fsnotify_inode_delete(struct inode *inode)
        __fsnotify_inode_delete(inode);
 }
 
+/*
+ * fsnotify_vfsmount_delete - a vfsmount is being destroyed, clean up is needed
+ */
+static inline void fsnotify_vfsmount_delete(struct vfsmount *mnt)
+{
+       __fsnotify_vfsmount_delete(mnt);
+}
+
 /*
  * fsnotify_nameremove - a filename was removed from a directory
  */

diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index f21ff1bd4b5aa9c985f417a113b74de38e0ac61f..1af42cbfc4294edda82e3f785a17b7dc3c776c71 100644 (file)
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -282,6 +282,7 @@ extern void fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is,
                     const char *name, u32 cookie);
 extern void __fsnotify_parent(struct path *path, struct dentry *dentry, __u32 mask);
 extern void __fsnotify_inode_delete(struct inode *inode);
+extern void __fsnotify_vfsmount_delete(struct vfsmount *mnt);
 extern u32 fsnotify_get_cookie(void);
 
 static inline int fsnotify_inode_watches_children(struct inode *inode)
@@ -402,6 +403,9 @@ static inline void __fsnotify_parent(struct path *path, struct dentry *dentry, _
 static inline void __fsnotify_inode_delete(struct inode *inode)
 {}
 
+static inline void __fsnotify_vfsmount_delete(struct vfsmount *mnt)
+{}
+
 static inline void __fsnotify_update_dcache_flags(struct dentry *dentry)
 {}