From patchwork Fri Apr 15 12:35:57 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12814860 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DB0FBC433EF for ; Fri, 15 Apr 2022 12:37:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353700AbiDOMj2 (ORCPT ); Fri, 15 Apr 2022 08:39:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39610 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1353569AbiDOMi7 (ORCPT ); Fri, 15 Apr 2022 08:38:59 -0400 Received: from out30-132.freemail.mail.aliyun.com (out30-132.freemail.mail.aliyun.com [115.124.30.132]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C7D4253B75; Fri, 15 Apr 2022 05:36:26 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R681e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04407;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=19;SR=0;TI=SMTPD_---0VA7VPQE_1650026181; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0VA7VPQE_1650026181) by smtp.aliyun-inc.com(127.0.0.1); Fri, 15 Apr 2022 20:36:22 +0800 From: Jeffle Xu To: dhowells@redhat.com, linux-cachefs@redhat.com, xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org Cc: torvalds@linux-foundation.org, gregkh@linuxfoundation.org, willy@infradead.org, linux-fsdevel@vger.kernel.org, joseph.qi@linux.alibaba.com, bo.liu@linux.alibaba.com, tao.peng@linux.alibaba.com, gerry@linux.alibaba.com, eguan@linux.alibaba.com, linux-kernel@vger.kernel.org, luodaowen.backend@bytedance.com, tianzichen@kuaishou.com, fannaihao@baidu.com, zhangjiachen.jaycee@bytedance.com Subject: [PATCH v9 04/21] cachefiles: notify user daemon when withdrawing cookie Date: Fri, 15 Apr 2022 20:35:57 +0800 Message-Id: <20220415123614.54024-5-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20220415123614.54024-1-jefflexu@linux.alibaba.com> References: <20220415123614.54024-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Notify the user daemon that cookie is going to be withdrawn, providing a hint that the associated anonymous fd can be closed. Be noted that this is only a hint. The user daemon may close the associated anonymous fd when receiving the CLOSE request, then it will receive another anonymous fd when the cookie gets looked up. Or it may ignore the CLOSE request, and keep writing data through the anonymous fd. However the next time the cookie gets looked up, the user daemon will still receive another new anonymous fd. Signed-off-by: Jeffle Xu Acked-by: David Howells --- fs/cachefiles/interface.c | 2 ++ fs/cachefiles/internal.h | 5 +++++ fs/cachefiles/ondemand.c | 38 +++++++++++++++++++++++++++++++++ include/uapi/linux/cachefiles.h | 1 + 4 files changed, 46 insertions(+) diff --git a/fs/cachefiles/interface.c b/fs/cachefiles/interface.c index ae93cee9d25d..a69073a1d3f0 100644 --- a/fs/cachefiles/interface.c +++ b/fs/cachefiles/interface.c @@ -362,6 +362,8 @@ static void cachefiles_withdraw_cookie(struct fscache_cookie *cookie) spin_unlock(&cache->object_list_lock); } + cachefiles_ondemand_clean_object(object); + if (object->file) { cachefiles_begin_secure(cache, &saved_cred); cachefiles_clean_up_object(object, cache); diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h index 9b83d8c82709..15332eae43c0 100644 --- a/fs/cachefiles/internal.h +++ b/fs/cachefiles/internal.h @@ -286,6 +286,7 @@ extern int cachefiles_ondemand_copen(struct cachefiles_cache *cache, char *args); extern int cachefiles_ondemand_init_object(struct cachefiles_object *object); +extern void cachefiles_ondemand_clean_object(struct cachefiles_object *object); #else static inline ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache, @@ -298,6 +299,10 @@ static inline int cachefiles_ondemand_init_object(struct cachefiles_object *obje { return 0; } + +static inline void cachefiles_ondemand_clean_object(struct cachefiles_object *object) +{ +} #endif /* diff --git a/fs/cachefiles/ondemand.c b/fs/cachefiles/ondemand.c index eec883640efa..7ce383536f27 100644 --- a/fs/cachefiles/ondemand.c +++ b/fs/cachefiles/ondemand.c @@ -229,6 +229,12 @@ ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache, goto err_put_fd; } + /* CLOSE request has no reply */ + if (msg->opcode == CACHEFILES_OP_CLOSE) { + xa_erase(&cache->reqs, id); + complete(&req->done); + } + return n; err_put_fd: @@ -293,6 +299,13 @@ static int cachefiles_ondemand_send_req(struct cachefiles_object *object, goto out; } + if (opcode != CACHEFILES_OP_OPEN && object->ondemand_id <= 0) { + WARN_ON_ONCE(object->ondemand_id == 0); + xas_unlock(&xas); + ret = -EIO; + goto out; + } + xas.xa_index = 0; xas_find_marked(&xas, UINT_MAX, XA_FREE_MARK); if (xas.xa_node == XAS_RESTART) @@ -349,6 +362,25 @@ static int cachefiles_ondemand_init_open_req(struct cachefiles_req *req, return 0; } +static int cachefiles_ondemand_init_close_req(struct cachefiles_req *req, + void *private) +{ + struct cachefiles_object *object = req->object; + int object_id = object->ondemand_id; + + /* + * It's possiblie that object id is still 0 if the cookie looking up + * phase failed before OPEN request has ever been sent. Also avoid + * sending CLOSE request for CACHEFILES_ONDEMAND_ID_CLOSED, which means + * anon_fd has already been closed. + */ + if (object_id <= 0) + return -ENOENT; + + req->msg.object_id = object_id; + return 0; +} + int cachefiles_ondemand_init_object(struct cachefiles_object *object) { struct fscache_cookie *cookie = object->cookie; @@ -372,3 +404,9 @@ int cachefiles_ondemand_init_object(struct cachefiles_object *object) return cachefiles_ondemand_send_req(object, CACHEFILES_OP_OPEN, data_len, cachefiles_ondemand_init_open_req, NULL); } + +void cachefiles_ondemand_clean_object(struct cachefiles_object *object) +{ + cachefiles_ondemand_send_req(object, CACHEFILES_OP_CLOSE, 0, + cachefiles_ondemand_init_close_req, NULL); +} diff --git a/include/uapi/linux/cachefiles.h b/include/uapi/linux/cachefiles.h index 521f2fe4fe9c..37a0071037c8 100644 --- a/include/uapi/linux/cachefiles.h +++ b/include/uapi/linux/cachefiles.h @@ -12,6 +12,7 @@ enum cachefiles_opcode { CACHEFILES_OP_OPEN, + CACHEFILES_OP_CLOSE, }; /*