On Thu 12-08-21 17:40:07, Gabriel Krisman Bertazi wrote:
> The Error info type is a record sent to users on FAN_FS_ERROR events
> documenting the type of error. It also carries an error count,
> documenting how many errors were observed since the last reporting.
>
> Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx>
Looks good. Feel free to add:
Reviewed-by: Jan Kara <jack@xxxxxxx>
Honza
>
> ---
> Changes since v5:
> - Move error code here
> ---
> fs/notify/fanotify/fanotify.c | 1 +
> fs/notify/fanotify/fanotify.h | 1 +
> fs/notify/fanotify/fanotify_user.c | 36 ++++++++++++++++++++++++++++++
> include/uapi/linux/fanotify.h | 7 ++++++
> 4 files changed, 45 insertions(+)
>
> diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
> index f5c16ac37835..b49a474c1d7f 100644
> --- a/fs/notify/fanotify/fanotify.c
> +++ b/fs/notify/fanotify/fanotify.c
> @@ -745,6 +745,7 @@ static int fanotify_handle_error_event(struct fsnotify_iter_info *iter_info,
> spin_unlock(&group->notification_lock);
>
> fee->fae.type = FANOTIFY_EVENT_TYPE_FS_ERROR;
> + fee->error = report->error;
> fee->fsid = fee->sb_mark->fsn_mark.connector->fsid;
>
> fh_len = fanotify_encode_fh_len(inode);
> diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h
> index 158cf0c4b0bd..0cfe376c6fd9 100644
> --- a/fs/notify/fanotify/fanotify.h
> +++ b/fs/notify/fanotify/fanotify.h
> @@ -220,6 +220,7 @@ FANOTIFY_NE(struct fanotify_event *event)
>
> struct fanotify_error_event {
> struct fanotify_event fae;
> + s32 error; /* Error reported by the Filesystem. */
> u32 err_count; /* Suppressed errors count */
>
> struct fanotify_sb_mark *sb_mark; /* Back reference to the mark. */
> diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
> index 1ab8f9d8b3ac..ca53159ce673 100644
> --- a/fs/notify/fanotify/fanotify_user.c
> +++ b/fs/notify/fanotify/fanotify_user.c
> @@ -107,6 +107,8 @@ struct kmem_cache *fanotify_perm_event_cachep __read_mostly;
> #define FANOTIFY_EVENT_ALIGN 4
> #define FANOTIFY_INFO_HDR_LEN \
> (sizeof(struct fanotify_event_info_fid) + sizeof(struct file_handle))
> +#define FANOTIFY_INFO_ERROR_LEN \
> + (sizeof(struct fanotify_event_info_error))
>
> static int fanotify_fid_info_len(int fh_len, int name_len)
> {
> @@ -130,6 +132,9 @@ static size_t fanotify_event_len(struct fanotify_event *event,
> if (!fid_mode)
> return event_len;
>
> + if (fanotify_is_error_event(event->mask))
> + event_len += FANOTIFY_INFO_ERROR_LEN;
> +
> info = fanotify_event_info(event);
> dir_fh_len = fanotify_event_dir_fh_len(event);
> fh_len = fanotify_event_object_fh_len(event);
> @@ -176,6 +181,7 @@ static struct fanotify_event *fanotify_dup_error_to_stack(
> error_on_stack->fae.type = FANOTIFY_EVENT_TYPE_FS_ERROR;
> error_on_stack->err_count = fee->err_count;
> error_on_stack->sb_mark = fee->sb_mark;
> + error_on_stack->error = fee->error;
>
> error_on_stack->fsid = fee->fsid;
>
> @@ -342,6 +348,28 @@ static int process_access_response(struct fsnotify_group *group,
> return -ENOENT;
> }
>
> +static size_t copy_error_info_to_user(struct fanotify_event *event,
> + char __user *buf, int count)
> +{
> + struct fanotify_event_info_error info;
> + struct fanotify_error_event *fee = FANOTIFY_EE(event);
> +
> + info.hdr.info_type = FAN_EVENT_INFO_TYPE_ERROR;
> + info.hdr.pad = 0;
> + info.hdr.len = FANOTIFY_INFO_ERROR_LEN;
> +
> + if (WARN_ON(count < info.hdr.len))
> + return -EFAULT;
> +
> + info.error = fee->error;
> + info.error_count = fee->err_count;
> +
> + if (copy_to_user(buf, &info, sizeof(info)))
> + return -EFAULT;
> +
> + return info.hdr.len;
> +}
> +
> 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)
> @@ -505,6 +533,14 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group,
> if (f)
> fd_install(fd, f);
>
> + if (fanotify_is_error_event(event->mask)) {
> + ret = copy_error_info_to_user(event, buf, count);
> + if (ret < 0)
> + goto out_close_fd;
> + buf += ret;
> + count -= ret;
> + }
> +
> /* Event info records order is: dir fid + name, child fid */
> if (fanotify_event_dir_fh_len(event)) {
> info_type = info->name_len ? FAN_EVENT_INFO_TYPE_DFID_NAME :
> diff --git a/include/uapi/linux/fanotify.h b/include/uapi/linux/fanotify.h
> index 16402037fc7a..80040a92e9d9 100644
> --- a/include/uapi/linux/fanotify.h
> +++ b/include/uapi/linux/fanotify.h
> @@ -124,6 +124,7 @@ struct fanotify_event_metadata {
> #define FAN_EVENT_INFO_TYPE_FID 1
> #define FAN_EVENT_INFO_TYPE_DFID_NAME 2
> #define FAN_EVENT_INFO_TYPE_DFID 3
> +#define FAN_EVENT_INFO_TYPE_ERROR 4
>
> /* Variable length info record following event metadata */
> struct fanotify_event_info_header {
> @@ -149,6 +150,12 @@ struct fanotify_event_info_fid {
> unsigned char handle[0];
> };
>
> +struct fanotify_event_info_error {
> + struct fanotify_event_info_header hdr;
> + __s32 error;
> + __u32 error_count;
> +};
> +
> struct fanotify_response {
> __s32 fd;
> __u32 response;
> --
> 2.32.0
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
