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From:   Siddh Raman Pant <code@siddh.me>
To:     Eric Biggers <ebiggers@kernel.org>,
        Jonathan Corbet <corbet@lwn.net>,
        David Howells <dhowells@redhat.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Christophe JAILLET <christophe.jaillet@wanadoo.fr>,
        Eric Dumazet <edumazet@google.com>
Cc:     linux-kernel <linux-kernel@vger.kernel.org>,
        linux-kernel-mentees 
        <linux-kernel-mentees@lists.linuxfoundation.org>
Message-ID: <d25b2a4772bf8d2a37bbf1bd2c6ad82b13081762.1659771577.git.code@siddh.me>
Subject: [PATCH v2 1/2] include/linux/watch_queue: Improve documentation
Date:   Sat,  6 Aug 2022 13:13:41 +0530
In-Reply-To: <cover.1659771577.git.code@siddh.me>
References: <cover.1659771577.git.code@siddh.me>
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Precedence: bulk

Introduce kerneldoc-style comments, and document a couple of things
explicitly.

Signed-off-by: Siddh Raman Pant <code@siddh.me>
---
 include/linux/watch_queue.h | 102 ++++++++++++++++++++++++++----------
 1 file changed, 75 insertions(+), 27 deletions(-)

diff --git a/include/linux/watch_queue.h b/include/linux/watch_queue.h
index fc6bba20273b..7f8b1f15634b 100644
--- a/include/linux/watch_queue.h
+++ b/include/linux/watch_queue.h
@@ -18,57 +18,103 @@
=20
 struct cred;
=20
+/**
+ * struct watch_type_filter - Filter on watch type
+ *
+ * @type: Type of watch_notification
+ * @subtype_filter: Bitmask of subtypes to filter on
+ * @info_filter: Filter on watch_notification::info
+ * @info_mask: Mask of relevant bits in info_filter
+ */
 struct watch_type_filter {
 =09enum watch_notification_type type;
-=09__u32=09=09subtype_filter[1];=09/* Bitmask of subtypes to filter on */
-=09__u32=09=09info_filter;=09=09/* Filter on watch_notification::info */
-=09__u32=09=09info_mask;=09=09/* Mask of relevant bits in info_filter */
+=09__u32=09=09subtype_filter[1];
+=09__u32=09=09info_filter;
+=09__u32=09=09info_mask;
 };
=20
+/**
+ * struct watch_filter - Filter on watch
+ *
+ * @rcu: RCU head (in union with type_filter)
+ * @type_filter: Bitmask of accepted types (in union with rcu)
+ * @nr_filters: Number of filters
+ * @filters: Array of watch_type_filter
+ */
 struct watch_filter {
 =09union {
 =09=09struct rcu_head=09rcu;
-=09=09/* Bitmask of accepted types */
 =09=09DECLARE_BITMAP(type_filter, WATCH_TYPE__NR);
 =09};
-=09u32=09=09=09nr_filters;=09/* Number of filters */
+=09u32=09=09=09 nr_filters;
 =09struct watch_type_filter filters[];
 };
=20
+/**
+ * struct watch_queue - General notification queue
+ *
+ * @rcu: RCU head
+ * @filter: Filter to use on watches
+ * @pipe: The pipe we're using as a buffer
+ * @watches: Contributory watches
+ * @notes: Preallocated notifications
+ * @notes_bitmap: Allocation bitmap for notes
+ * @usage: Object usage count
+ * @lock: To serialize accesses and removes
+ * @nr_notes: Number of notes
+ * @nr_pages: Number of pages in notes[]
+ * @defunct: True when queues closed
+ */
 struct watch_queue {
 =09struct rcu_head=09=09rcu;
 =09struct watch_filter __rcu *filter;
-=09struct pipe_inode_info=09*pipe;=09=09/* The pipe we're using as a buffe=
r */
-=09struct hlist_head=09watches;=09/* Contributory watches */
-=09struct page=09=09**notes;=09/* Preallocated notifications */
-=09unsigned long=09=09*notes_bitmap;=09/* Allocation bitmap for notes */
-=09struct kref=09=09usage;=09=09/* Object usage count */
+=09struct pipe_inode_info=09*pipe;
+=09struct hlist_head=09watches;
+=09struct page=09=09**notes;
+=09unsigned long=09=09*notes_bitmap;
+=09struct kref=09=09usage;
 =09spinlock_t=09=09lock;
-=09unsigned int=09=09nr_notes;=09/* Number of notes */
-=09unsigned int=09=09nr_pages;=09/* Number of pages in notes[] */
-=09bool=09=09=09defunct;=09/* T when queues closed */
+=09unsigned int=09=09nr_notes;
+=09unsigned int=09=09nr_pages;
+=09bool=09=09=09defunct;
 };
=20
-/*
- * Representation of a watch on an object.
+/**
+ * struct watch - Representation of a watch on an object
+ *
+ * @rcu: RCU head (in union with info_id)
+ * @info_id: ID to be OR'd in to info field (in union with rcu)
+ * @queue: Queue to post events to
+ * @queue_node: Link in queue->watches
+ * @watch_list: Link in watch_list->watchers
+ * @list_node: The list node
+ * @cred: Creds of the owner of the watch
+ * @private: Private data for the watched object
+ * @id: Internal identifier
+ * @usage: Object usage count
  */
 struct watch {
 =09union {
 =09=09struct rcu_head=09rcu;
-=09=09u32=09=09info_id;=09/* ID to be OR'd in to info field */
+=09=09u32=09=09info_id;
 =09};
-=09struct watch_queue __rcu *queue;=09/* Queue to post events to */
-=09struct hlist_node=09queue_node;=09/* Link in queue->watches */
+=09struct watch_queue __rcu *queue;
+=09struct hlist_node=09queue_node;
 =09struct watch_list __rcu=09*watch_list;
-=09struct hlist_node=09list_node;=09/* Link in watch_list->watchers */
-=09const struct cred=09*cred;=09=09/* Creds of the owner of the watch */
-=09void=09=09=09*private;=09/* Private data for the watched object */
-=09u64=09=09=09id;=09=09/* Internal identifier */
-=09struct kref=09=09usage;=09=09/* Object usage count */
+=09struct hlist_node=09list_node;
+=09const struct cred=09*cred;
+=09void=09=09=09*private;
+=09u64=09=09=09id;
+=09struct kref=09=09usage;
 };
=20
-/*
- * List of watches on an object.
+/**
+ * struct watch_list - List of watches on an object
+ *
+ * @rcu: RCU head
+ * @watchers: List head
+ * @release_watch: Function to release watch
+ * @lock: To protect addition and removal of watches
  */
 struct watch_list {
 =09struct rcu_head=09=09rcu;
@@ -118,8 +164,10 @@ static inline void remove_watch_list(struct watch_list=
 *wlist, u64 id)
 }
=20
 /**
- * watch_sizeof - Calculate the information part of the size of a watch re=
cord,
- * given the structure size.
+ * watch_sizeof() - Calculate the information part of the size of a watch
+ *=09=09    record, given the structure size.
+ *
+ * @STRUCT: The structure whose size is to be given
  */
 #define watch_sizeof(STRUCT) (sizeof(STRUCT) << WATCH_INFO_LENGTH__SHIFT)
=20
--=20
2.35.1