[External] [PATCH v3 5/9] cachefiles: stop sending new request when dropping object

[Jia Zhu]

在 2024/6/28 14:29, libaokun at huaweicloud.com 写道:
> From: Baokun Li <libaokun1 at huawei.com>
> 
> Added CACHEFILES_ONDEMAND_OBJSTATE_DROPPING indicates that the cachefiles
> object is being dropped, and is set after the close request for the dropped
> object completes, and no new requests are allowed to be sent after this
> state.
> 
> This prepares for the later addition of cancel_work_sync(). It prevents
> leftover reopen requests from being sent, to avoid processing unnecessary
> requests and to avoid cancel_work_sync() blocking by waiting for daemon to
> complete the reopen requests.
> 
> Signed-off-by: Baokun Li <libaokun1 at huawei.com>
> Acked-by: Jeff Layton <jlayton at kernel.org>

Reviewed-by: Jia Zhu <zhujia.zj at bytedance.com>

> ---
>   fs/cachefiles/internal.h |  2 ++
>   fs/cachefiles/ondemand.c | 10 ++++++++--
>   2 files changed, 10 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h
> index 6845a90cdfcc..a1a1d25e9514 100644
> --- a/fs/cachefiles/internal.h
> +++ b/fs/cachefiles/internal.h
> @@ -48,6 +48,7 @@ enum cachefiles_object_state {
>   	CACHEFILES_ONDEMAND_OBJSTATE_CLOSE, /* Anonymous fd closed by daemon or initial state */
>   	CACHEFILES_ONDEMAND_OBJSTATE_OPEN, /* Anonymous fd associated with object is available */
>   	CACHEFILES_ONDEMAND_OBJSTATE_REOPENING, /* Object that was closed and is being reopened. */
> +	CACHEFILES_ONDEMAND_OBJSTATE_DROPPING, /* Object is being dropped. */
>   };
>   
>   struct cachefiles_ondemand_info {
> @@ -335,6 +336,7 @@ cachefiles_ondemand_set_object_##_state(struct cachefiles_object *object) \
>   CACHEFILES_OBJECT_STATE_FUNCS(open, OPEN);
>   CACHEFILES_OBJECT_STATE_FUNCS(close, CLOSE);
>   CACHEFILES_OBJECT_STATE_FUNCS(reopening, REOPENING);
> +CACHEFILES_OBJECT_STATE_FUNCS(dropping, DROPPING);
>   
>   static inline bool cachefiles_ondemand_is_reopening_read(struct cachefiles_req *req)
>   {
> diff --git a/fs/cachefiles/ondemand.c b/fs/cachefiles/ondemand.c
> index bce005f2b456..8a3b52c3ebba 100644
> --- a/fs/cachefiles/ondemand.c
> +++ b/fs/cachefiles/ondemand.c
> @@ -517,7 +517,8 @@ static int cachefiles_ondemand_send_req(struct cachefiles_object *object,
>   		 */
>   		xas_lock(&xas);
>   
> -		if (test_bit(CACHEFILES_DEAD, &cache->flags)) {
> +		if (test_bit(CACHEFILES_DEAD, &cache->flags) ||
> +		    cachefiles_ondemand_object_is_dropping(object)) {
>   			xas_unlock(&xas);
>   			ret = -EIO;
>   			goto out;
> @@ -568,7 +569,8 @@ static int cachefiles_ondemand_send_req(struct cachefiles_object *object,
>   	 * If error occurs after creating the anonymous fd,
>   	 * cachefiles_ondemand_fd_release() will set object to close.
>   	 */
> -	if (opcode == CACHEFILES_OP_OPEN)
> +	if (opcode == CACHEFILES_OP_OPEN &&
> +	    !cachefiles_ondemand_object_is_dropping(object))
>   		cachefiles_ondemand_set_object_close(object);
>   	kfree(req);
>   	return ret;
> @@ -667,8 +669,12 @@ int cachefiles_ondemand_init_object(struct cachefiles_object *object)
>   
>   void cachefiles_ondemand_clean_object(struct cachefiles_object *object)
>   {
> +	if (!object->ondemand)
> +		return;
> +
>   	cachefiles_ondemand_send_req(object, CACHEFILES_OP_CLOSE, 0,
>   			cachefiles_ondemand_init_close_req, NULL);
> +	cachefiles_ondemand_set_object_dropping(object);
>   }
>   
>   int cachefiles_ondemand_init_obj_info(struct cachefiles_object *object,