On Wed, Jul 21, 2021 at 9:18 AM Matthew Bobrowski <repnop@xxxxxxxxxx> wrote:
>
> With the idea to support additional info record types in the future
> i.e. fanotify_event_info_pidfd, it's a good idea to rename some of the
> labels assigned to some of the existing fid related functions,
> parameters, etc which more accurately represent the intent behind
> their usage.
>
> For example, copy_info_to_user() was defined with a generic function
> label, which arguably reads as being supportive of different info
> record types, however the parameter list for this function is
> explicitly tailored towards the creation and copying of the
> fanotify_event_info_fid records. This same point applies to the macro
> defined as FANOTIFY_INFO_HDR_LEN.
>
> With fanotify_event_info_len(), we change the parameter label so that
> the function implies that it can be extended to calculate the length
> for additional info record types.
>
> Signed-off-by: Matthew Bobrowski <repnop@xxxxxxxxxx>
Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx>
> ---
> fs/notify/fanotify/fanotify_user.c | 33 +++++++++++++++++-------------
> 1 file changed, 19 insertions(+), 14 deletions(-)
>
> diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
> index 64864fb40b40..182fea255376 100644
> --- a/fs/notify/fanotify/fanotify_user.c
> +++ b/fs/notify/fanotify/fanotify_user.c
> @@ -104,7 +104,7 @@ struct kmem_cache *fanotify_path_event_cachep __read_mostly;
> struct kmem_cache *fanotify_perm_event_cachep __read_mostly;
>
> #define FANOTIFY_EVENT_ALIGN 4
> -#define FANOTIFY_INFO_HDR_LEN \
> +#define FANOTIFY_FID_INFO_HDR_LEN \
> (sizeof(struct fanotify_event_info_fid) + sizeof(struct file_handle))
>
> static int fanotify_fid_info_len(int fh_len, int name_len)
> @@ -114,10 +114,11 @@ static int fanotify_fid_info_len(int fh_len, int name_len)
> if (name_len)
> info_len += name_len + 1;
>
> - return roundup(FANOTIFY_INFO_HDR_LEN + info_len, FANOTIFY_EVENT_ALIGN);
> + return roundup(FANOTIFY_FID_INFO_HDR_LEN + info_len,
> + FANOTIFY_EVENT_ALIGN);
> }
>
> -static int fanotify_event_info_len(unsigned int fid_mode,
> +static int fanotify_event_info_len(unsigned int info_mode,
> struct fanotify_event *event)
> {
> struct fanotify_info *info = fanotify_event_info(event);
> @@ -128,7 +129,8 @@ static int fanotify_event_info_len(unsigned int fid_mode,
>
> if (dir_fh_len) {
> info_len += fanotify_fid_info_len(dir_fh_len, info->name_len);
> - } else if ((fid_mode & FAN_REPORT_NAME) && (event->mask & FAN_ONDIR)) {
> + } else if ((info_mode & FAN_REPORT_NAME) &&
> + (event->mask & FAN_ONDIR)) {
> /*
> * With group flag FAN_REPORT_NAME, if name was not recorded in
> * event on a directory, we will report the name ".".
> @@ -303,9 +305,10 @@ static int process_access_response(struct fsnotify_group *group,
> return -ENOENT;
> }
>
> -static int copy_info_to_user(__kernel_fsid_t *fsid, struct fanotify_fh *fh,
> - int info_type, const char *name, size_t name_len,
> - char __user *buf, size_t count)
> +static int copy_fid_info_to_user(__kernel_fsid_t *fsid, struct fanotify_fh *fh,
> + int info_type, const char *name,
> + size_t name_len,
> + char __user *buf, size_t count)
> {
> struct fanotify_event_info_fid info = { };
> struct file_handle handle = { };
> @@ -466,10 +469,11 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group,
> if (fanotify_event_dir_fh_len(event)) {
> info_type = info->name_len ? FAN_EVENT_INFO_TYPE_DFID_NAME :
> FAN_EVENT_INFO_TYPE_DFID;
> - ret = copy_info_to_user(fanotify_event_fsid(event),
> - fanotify_info_dir_fh(info),
> - info_type, fanotify_info_name(info),
> - info->name_len, buf, count);
> + ret = copy_fid_info_to_user(fanotify_event_fsid(event),
> + fanotify_info_dir_fh(info),
> + info_type,
> + fanotify_info_name(info),
> + info->name_len, buf, count);
> if (ret < 0)
> goto out_close_fd;
>
> @@ -515,9 +519,10 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group,
> info_type = FAN_EVENT_INFO_TYPE_FID;
> }
>
> - ret = copy_info_to_user(fanotify_event_fsid(event),
> - fanotify_event_object_fh(event),
> - info_type, dot, dot_len, buf, count);
> + ret = copy_fid_info_to_user(fanotify_event_fsid(event),
> + fanotify_event_object_fh(event),
> + info_type, dot, dot_len,
> + buf, count);
> if (ret < 0)
> goto out_close_fd;
>
> --
> 2.32.0.432.gabb21c7263-goog
>
> /M
