fanotify: Add helpers to decide whether to report FID/DFID

Now that there is an event that reports FID records even for a zeroed
file handle, wrap the logic that deides whether to issue the records
into helper functions.  This shouldn't have any impact on the code, but
simplifies further patches.

Link: https://lore.kernel.org/r/20211025192746.66445-24-krisman@collabora.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h
index 3510d06..80af269 100644 (file)
--- a/fs/notify/fanotify/fanotify.h
+++ b/fs/notify/fanotify/fanotify.h
@@ -264,6 +264,16 @@ static inline int fanotify_event_dir_fh_len(struct fanotify_event *event)
        return info ? fanotify_info_dir_fh_len(info) : 0;
 }
 
+static inline bool fanotify_event_has_object_fh(struct fanotify_event *event)
+{
+       return fanotify_event_object_fh_len(event) > 0;
+}
+
+static inline bool fanotify_event_has_dir_fh(struct fanotify_event *event)
+{
+       return fanotify_event_dir_fh_len(event) > 0;
+}
+
 struct fanotify_path_event {
        struct fanotify_event fae;
        struct path path;

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 2f4182b..a9b5c36 100644 (file)
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -140,10 +140,9 @@ static size_t fanotify_event_len(unsigned int info_mode,
                return event_len;
 
        info = fanotify_event_info(event);
-       dir_fh_len = fanotify_event_dir_fh_len(event);
-       fh_len = fanotify_event_object_fh_len(event);
 
-       if (dir_fh_len) {
+       if (fanotify_event_has_dir_fh(event)) {
+               dir_fh_len = fanotify_event_dir_fh_len(event);
                event_len += fanotify_fid_info_len(dir_fh_len, info->name_len);
        } else if ((info_mode & FAN_REPORT_NAME) &&
                   (event->mask & FAN_ONDIR)) {
@@ -157,8 +156,10 @@ static size_t fanotify_event_len(unsigned int info_mode,
        if (info_mode & FAN_REPORT_PIDFD)
                event_len += FANOTIFY_PIDFD_INFO_HDR_LEN;
 
-       if (fh_len)
+       if (fanotify_event_has_object_fh(event)) {
+               fh_len = fanotify_event_object_fh_len(event);
                event_len += fanotify_fid_info_len(fh_len, dot_len);
+       }
 
        return event_len;
 }
@@ -451,7 +452,7 @@ static int copy_info_records_to_user(struct fanotify_event *event,
        /*
         * Event info records order is as follows: dir fid + name, child fid.
         */
-       if (fanotify_event_dir_fh_len(event)) {
+       if (fanotify_event_has_dir_fh(event)) {
                info_type = info->name_len ? FAN_EVENT_INFO_TYPE_DFID_NAME :
                                             FAN_EVENT_INFO_TYPE_DFID;
                ret = copy_fid_info_to_user(fanotify_event_fsid(event),
@@ -467,7 +468,7 @@ static int copy_info_records_to_user(struct fanotify_event *event,
                total_bytes += ret;
        }
 
-       if (fanotify_event_object_fh_len(event)) {
+       if (fanotify_event_has_object_fh(event)) {
                const char *dot = NULL;
                int dot_len = 0;