On Tue, Oct 19, 2021 at 3:03 AM Gabriel Krisman Bertazi
<krisman@xxxxxxxxxxxxx> wrote:
>
> Once an error event is triggered, enqueue it in the notification group,
> similarly to what is done for other events. FAN_FS_ERROR is not
> handled specially, since the memory is now handled by a preallocated
> mempool.
>
> For now, make the event unhashed. A future patch implements merging of
> this kind of event.
>
> Reviewed-by: Jan Kara <jack@xxxxxxx>
> Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx>
>
Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx>
> ---
> Changes since v7:
> - WARN_ON -> WARN_ON_ONCE (Amir)
> ---
> fs/notify/fanotify/fanotify.c | 35 +++++++++++++++++++++++++++++++++++
> fs/notify/fanotify/fanotify.h | 6 ++++++
> 2 files changed, 41 insertions(+)
>
> diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
> index 01d68dfc74aa..1f195c95dfcd 100644
> --- a/fs/notify/fanotify/fanotify.c
> +++ b/fs/notify/fanotify/fanotify.c
> @@ -574,6 +574,27 @@ static struct fanotify_event *fanotify_alloc_name_event(struct inode *id,
> return &fne->fae;
> }
>
> +static struct fanotify_event *fanotify_alloc_error_event(
> + struct fsnotify_group *group,
> + __kernel_fsid_t *fsid,
> + const void *data, int data_type)
> +{
> + struct fs_error_report *report =
> + fsnotify_data_error_report(data, data_type);
> + struct fanotify_error_event *fee;
> +
> + if (WARN_ON_ONCE(!report))
> + return NULL;
> +
> + fee = mempool_alloc(&group->fanotify_data.error_events_pool, GFP_NOFS);
> + if (!fee)
> + return NULL;
> +
> + fee->fae.type = FANOTIFY_EVENT_TYPE_FS_ERROR;
> +
> + return &fee->fae;
> +}
> +
> static struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group,
> u32 mask, const void *data,
> int data_type, struct inode *dir,
> @@ -641,6 +662,9 @@ static struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group,
>
> if (fanotify_is_perm_event(mask)) {
> event = fanotify_alloc_perm_event(path, gfp);
> + } else if (fanotify_is_error_event(mask)) {
> + event = fanotify_alloc_error_event(group, fsid, data,
> + data_type);
> } else if (name_event && (file_name || child)) {
> event = fanotify_alloc_name_event(id, fsid, file_name, child,
> &hash, gfp);
> @@ -850,6 +874,14 @@ static void fanotify_free_name_event(struct fanotify_event *event)
> kfree(FANOTIFY_NE(event));
> }
>
> +static void fanotify_free_error_event(struct fsnotify_group *group,
> + struct fanotify_event *event)
> +{
> + struct fanotify_error_event *fee = FANOTIFY_EE(event);
> +
> + mempool_free(fee, &group->fanotify_data.error_events_pool);
> +}
> +
> static void fanotify_free_event(struct fsnotify_group *group,
> struct fsnotify_event *fsn_event)
> {
> @@ -873,6 +905,9 @@ static void fanotify_free_event(struct fsnotify_group *group,
> case FANOTIFY_EVENT_TYPE_OVERFLOW:
> kfree(event);
> break;
> + case FANOTIFY_EVENT_TYPE_FS_ERROR:
> + fanotify_free_error_event(group, event);
> + break;
> default:
> WARN_ON_ONCE(1);
> }
> diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h
> index a577e87fac2b..ebef952481fa 100644
> --- a/fs/notify/fanotify/fanotify.h
> +++ b/fs/notify/fanotify/fanotify.h
> @@ -298,6 +298,11 @@ static inline struct fanotify_event *FANOTIFY_E(struct fsnotify_event *fse)
> return container_of(fse, struct fanotify_event, fse);
> }
>
> +static inline bool fanotify_is_error_event(u32 mask)
> +{
> + return mask & FAN_FS_ERROR;
> +}
> +
> static inline bool fanotify_event_has_path(struct fanotify_event *event)
> {
> return event->type == FANOTIFY_EVENT_TYPE_PATH ||
> @@ -327,6 +332,7 @@ static inline struct path *fanotify_event_path(struct fanotify_event *event)
> static inline bool fanotify_is_hashed_event(u32 mask)
> {
> return !(fanotify_is_perm_event(mask) ||
> + fanotify_is_error_event(mask) ||
> fsnotify_is_overflow_event(mask));
> }
>
> --
> 2.33.0
>
