On Mon, Apr 26, 2021 at 9:42 PM Gabriel Krisman Bertazi
<krisman@xxxxxxxxxxxxx> wrote:
>
> Introduce a flags field in fsnotify_group to track the mode of
> submission this group has.
>
> Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx>
> ---
> fs/notify/dnotify/dnotify.c | 2 +-
> fs/notify/fanotify/fanotify_user.c | 4 ++--
> fs/notify/group.c | 13 ++++++++-----
> fs/notify/inotify/inotify_user.c | 2 +-
> include/linux/fsnotify_backend.h | 7 +++++--
> kernel/audit_fsnotify.c | 2 +-
> kernel/audit_tree.c | 2 +-
> kernel/audit_watch.c | 2 +-
> 8 files changed, 20 insertions(+), 14 deletions(-)
>
> diff --git a/fs/notify/dnotify/dnotify.c b/fs/notify/dnotify/dnotify.c
> index e85e13c50d6d..37960c8750e4 100644
> --- a/fs/notify/dnotify/dnotify.c
> +++ b/fs/notify/dnotify/dnotify.c
> @@ -383,7 +383,7 @@ static int __init dnotify_init(void)
> SLAB_PANIC|SLAB_ACCOUNT);
> dnotify_mark_cache = KMEM_CACHE(dnotify_mark, SLAB_PANIC|SLAB_ACCOUNT);
>
> - dnotify_group = fsnotify_alloc_group(&dnotify_fsnotify_ops);
> + dnotify_group = fsnotify_alloc_group(&dnotify_fsnotify_ops, 0);
> if (IS_ERR(dnotify_group))
> panic("unable to allocate fsnotify group for dnotify\n");
> return 0;
> diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
> index e0d113e3b65c..f50c4ab721e3 100644
> --- a/fs/notify/fanotify/fanotify_user.c
> +++ b/fs/notify/fanotify/fanotify_user.c
> @@ -929,7 +929,7 @@ static struct fsnotify_event *fanotify_alloc_overflow_event(void)
> SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
> {
> struct fsnotify_group *group;
> - int f_flags, fd;
> + int f_flags, fd, fsn_flags = 0;
> struct user_struct *user;
> unsigned int fid_mode = flags & FANOTIFY_FID_BITS;
> unsigned int class = flags & FANOTIFY_CLASS_BITS;
> @@ -982,7 +982,7 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
> f_flags |= O_NONBLOCK;
>
> /* fsnotify_alloc_group takes a ref. Dropped in fanotify_release */
> - group = fsnotify_alloc_user_group(&fanotify_fsnotify_ops);
> + group = fsnotify_alloc_user_group(&fanotify_fsnotify_ops, fsn_flags);
> if (IS_ERR(group)) {
> free_uid(user);
> return PTR_ERR(group);
> diff --git a/fs/notify/group.c b/fs/notify/group.c
> index ffd723ffe46d..08acb1afc0c2 100644
> --- a/fs/notify/group.c
> +++ b/fs/notify/group.c
> @@ -112,7 +112,7 @@ void fsnotify_put_group(struct fsnotify_group *group)
> EXPORT_SYMBOL_GPL(fsnotify_put_group);
>
> static struct fsnotify_group *__fsnotify_alloc_group(
> - const struct fsnotify_ops *ops, gfp_t gfp)
> + const struct fsnotify_ops *ops, unsigned int flags, gfp_t gfp)
> {
> struct fsnotify_group *group;
>
> @@ -134,6 +134,7 @@ static struct fsnotify_group *__fsnotify_alloc_group(
> INIT_LIST_HEAD(&group->marks_list);
>
> group->ops = ops;
> + group->flags = flags;
>
> return group;
> }
> @@ -141,18 +142,20 @@ static struct fsnotify_group *__fsnotify_alloc_group(
> /*
> * Create a new fsnotify_group and hold a reference for the group returned.
> */
> -struct fsnotify_group *fsnotify_alloc_group(const struct fsnotify_ops *ops)
> +struct fsnotify_group *fsnotify_alloc_group(const struct fsnotify_ops *ops,
> + unsigned int flags)
> {
> - return __fsnotify_alloc_group(ops, GFP_KERNEL);
> + return __fsnotify_alloc_group(ops, flags, GFP_KERNEL);
> }
> EXPORT_SYMBOL_GPL(fsnotify_alloc_group);
>
> /*
> * Create a new fsnotify_group and hold a reference for the group returned.
> */
> -struct fsnotify_group *fsnotify_alloc_user_group(const struct fsnotify_ops *ops)
> +struct fsnotify_group *fsnotify_alloc_user_group(const struct fsnotify_ops *ops,
> + unsigned int flags)
> {
> - return __fsnotify_alloc_group(ops, GFP_KERNEL_ACCOUNT);
> + return __fsnotify_alloc_group(ops, flags, GFP_KERNEL_ACCOUNT);
> }
> EXPORT_SYMBOL_GPL(fsnotify_alloc_user_group);
>
*IF* we go this way, note that fsnotify_alloc_group() doesn't need
flags argument.
None of the callers of fsnotify_alloc_group() ever use the
notification list, so it
would be better to pass flag FSN_NOTIFICATION_LIST from the backends that
do use it (fanotify and inotify) for the sake of symmetry with FSN_RING_BUFFER
and no need to change other callers.
Thanks,
Amir.
