On Tue, Aug 03, 2021 at 09:03:42PM +0300, Amir Goldstein wrote:
> Instead of incrementing s_fsnotify_inode_refs when detaching connector
> from inode, increment it earlier when attaching connector to inode.
> Next patch is going to use s_fsnotify_inode_refs to count all objects
> with attached connectors.
>
> Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
LGTM.
Reviewed-by: Matthew Bobrowski <repnop@xxxxxxxxxx>
> ---
> fs/notify/mark.c | 29 ++++++++++++++++++-----------
> 1 file changed, 18 insertions(+), 11 deletions(-)
>
> diff --git a/fs/notify/mark.c b/fs/notify/mark.c
> index 80459db58f63..2d8c46e1167d 100644
> --- a/fs/notify/mark.c
> +++ b/fs/notify/mark.c
> @@ -169,6 +169,21 @@ static void fsnotify_connector_destroy_workfn(struct work_struct *work)
> }
> }
>
> +static void fsnotify_get_inode_ref(struct inode *inode)
> +{
> + ihold(inode);
> + atomic_long_inc(&inode->i_sb->s_fsnotify_inode_refs);
> +}
> +
> +static void fsnotify_put_inode_ref(struct inode *inode)
> +{
> + struct super_block *sb = inode->i_sb;
> +
> + iput(inode);
> + if (atomic_long_dec_and_test(&sb->s_fsnotify_inode_refs))
> + wake_up_var(&sb->s_fsnotify_inode_refs);
> +}
> +
> static void *fsnotify_detach_connector_from_object(
> struct fsnotify_mark_connector *conn,
> unsigned int *type)
> @@ -182,7 +197,6 @@ static void *fsnotify_detach_connector_from_object(
> if (conn->type == FSNOTIFY_OBJ_TYPE_INODE) {
> inode = fsnotify_conn_inode(conn);
> inode->i_fsnotify_mask = 0;
> - atomic_long_inc(&inode->i_sb->s_fsnotify_inode_refs);
> } else if (conn->type == FSNOTIFY_OBJ_TYPE_VFSMOUNT) {
> fsnotify_conn_mount(conn)->mnt_fsnotify_mask = 0;
> } else if (conn->type == FSNOTIFY_OBJ_TYPE_SB) {
> @@ -209,19 +223,12 @@ static void fsnotify_final_mark_destroy(struct fsnotify_mark *mark)
> /* Drop object reference originally held by a connector */
> static void fsnotify_drop_object(unsigned int type, void *objp)
> {
> - struct inode *inode;
> - struct super_block *sb;
> -
> if (!objp)
> return;
> /* Currently only inode references are passed to be dropped */
> if (WARN_ON_ONCE(type != FSNOTIFY_OBJ_TYPE_INODE))
> return;
> - inode = objp;
> - sb = inode->i_sb;
> - iput(inode);
> - if (atomic_long_dec_and_test(&sb->s_fsnotify_inode_refs))
> - wake_up_var(&sb->s_fsnotify_inode_refs);
> + fsnotify_put_inode_ref(objp);
> }
>
> void fsnotify_put_mark(struct fsnotify_mark *mark)
> @@ -495,7 +502,7 @@ static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp,
> }
> if (conn->type == FSNOTIFY_OBJ_TYPE_INODE) {
> inode = fsnotify_conn_inode(conn);
> - ihold(inode);
> + fsnotify_get_inode_ref(inode);
> }
>
> /*
> @@ -505,7 +512,7 @@ static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp,
> if (cmpxchg(connp, NULL, conn)) {
> /* Someone else created list structure for us */
> if (inode)
> - iput(inode);
> + fsnotify_put_inode_ref(inode);
> kmem_cache_free(fsnotify_mark_connector_cachep, conn);
> }
>
> --
> 2.25.1
>
/M
