diff options
Diffstat (limited to 'fs/notify/fanotify/fanotify.c')
-rw-r--r-- | fs/notify/fanotify/fanotify.c | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c new file mode 100644 index 000000000000..3ffb9dbcab08 --- /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, +}; |