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-rw-r--r--fs/notify/fanotify/Kconfig11
-rw-r--r--fs/notify/fanotify/Makefile1
-rw-r--r--fs/notify/fanotify/fanotify.c78
-rw-r--r--fs/notify/fanotify/fanotify.h12
4 files changed, 102 insertions, 0 deletions
diff --git a/fs/notify/fanotify/Kconfig b/fs/notify/fanotify/Kconfig
new file mode 100644
index 0000000..f9d7ae0
--- /dev/null
+++ b/fs/notify/fanotify/Kconfig
@@ -0,0 +1,11 @@
+config FANOTIFY
+ bool "Filesystem wide access notification"
+ select FSNOTIFY
+ default y
+ ---help---
+ Say Y here to enable fanotify suport. fanotify is a file access
+ notification system which differs from inotify in that it sends
+ and open file descriptor to the userspace listener along with
+ the event.
+
+ If unsure, say Y.
diff --git a/fs/notify/fanotify/Makefile b/fs/notify/fanotify/Makefile
new file mode 100644
index 0000000..e7d39c0
--- /dev/null
+++ b/fs/notify/fanotify/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_FANOTIFY) += fanotify.o
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
new file mode 100644
index 0000000..3ffb9db
--- /dev/null
+++ b/fs/notify/fanotify/fanotify.c
@@ -0,0 +1,78 @@
+#include <linux/fdtable.h>
+#include <linux/fsnotify_backend.h>
+#include <linux/init.h>
+#include <linux/kernel.h> /* UINT_MAX */
+#include <linux/types.h>
+
+#include "fanotify.h"
+
+static int fanotify_handle_event(struct fsnotify_group *group, struct fsnotify_event *event)
+{
+ int ret;
+
+
+ BUILD_BUG_ON(FAN_ACCESS != FS_ACCESS);
+ BUILD_BUG_ON(FAN_MODIFY != FS_MODIFY);
+ BUILD_BUG_ON(FAN_CLOSE_NOWRITE != FS_CLOSE_NOWRITE);
+ BUILD_BUG_ON(FAN_CLOSE_WRITE != FS_CLOSE_WRITE);
+ BUILD_BUG_ON(FAN_OPEN != FS_OPEN);
+ BUILD_BUG_ON(FAN_EVENT_ON_CHILD != FS_EVENT_ON_CHILD);
+ BUILD_BUG_ON(FAN_Q_OVERFLOW != FS_Q_OVERFLOW);
+
+ pr_debug("%s: group=%p event=%p\n", __func__, group, event);
+
+ ret = fsnotify_add_notify_event(group, event, NULL, NULL);
+
+ return ret;
+}
+
+static bool fanotify_should_send_event(struct fsnotify_group *group, struct inode *inode,
+ struct vfsmount *mnt, __u32 mask, void *data,
+ int data_type)
+{
+ struct fsnotify_mark *fsn_mark;
+ bool send;
+
+ pr_debug("%s: group=%p inode=%p mask=%x data=%p data_type=%d\n",
+ __func__, group, inode, mask, data, data_type);
+
+ /* sorry, fanotify only gives a damn about files and dirs */
+ if (!S_ISREG(inode->i_mode) &&
+ !S_ISDIR(inode->i_mode))
+ return false;
+
+ /* if we don't have enough info to send an event to userspace say no */
+ if (data_type != FSNOTIFY_EVENT_PATH)
+ return false;
+
+ fsn_mark = fsnotify_find_mark(group, inode);
+ if (!fsn_mark)
+ return false;
+
+ /* if the event is for a child and this inode doesn't care about
+ * events on the child, don't send it! */
+ if ((mask & FS_EVENT_ON_CHILD) &&
+ !(fsn_mark->mask & FS_EVENT_ON_CHILD)) {
+ send = false;
+ } else {
+ /*
+ * We care about children, but do we care about this particular
+ * type of event?
+ */
+ mask = (mask & ~FS_EVENT_ON_CHILD);
+ send = (fsn_mark->mask & mask);
+ }
+
+ /* find took a reference */
+ fsnotify_put_mark(fsn_mark);
+
+ return send;
+}
+
+const struct fsnotify_ops fanotify_fsnotify_ops = {
+ .handle_event = fanotify_handle_event,
+ .should_send_event = fanotify_should_send_event,
+ .free_group_priv = NULL,
+ .free_event_priv = NULL,
+ .freeing_mark = NULL,
+};
diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h
new file mode 100644
index 0000000..50765eb
--- /dev/null
+++ b/fs/notify/fanotify/fanotify.h
@@ -0,0 +1,12 @@
+#include <linux/fanotify.h>
+#include <linux/fsnotify_backend.h>
+#include <linux/net.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+
+static inline bool fanotify_mask_valid(__u32 mask)
+{
+ if (mask & ~((__u32)FAN_ALL_INCOMING_EVENTS))
+ return false;
+ return true;
+}
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