From patchwork Wed Mar 16 13:17:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12782662 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 4FB95C433FE for ; Wed, 16 Mar 2022 13:17:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356228AbiCPNS5 (ORCPT ); Wed, 16 Mar 2022 09:18:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52540 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1356200AbiCPNSt (ORCPT ); Wed, 16 Mar 2022 09:18:49 -0400 Received: from out30-44.freemail.mail.aliyun.com (out30-44.freemail.mail.aliyun.com [115.124.30.44]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CA6CA66AD6; Wed, 16 Mar 2022 06:17:34 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R151e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04395;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=16;SR=0;TI=SMTPD_---0V7NDH9x_1647436651; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0V7NDH9x_1647436651) by smtp.aliyun-inc.com(127.0.0.1); Wed, 16 Mar 2022 21:17:32 +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 Subject: [PATCH v5 05/22] cachefiles: notify user daemon when withdrawing cookie Date: Wed, 16 Mar 2022 21:17:06 +0800 Message-Id: <20220316131723.111553-6-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20220316131723.111553-1-jefflexu@linux.alibaba.com> References: <20220316131723.111553-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Notify user daemon that cookie is going to be withdrawed, providing a hint that the associated anon_fd can be closed. The anon_fd attached in the CLOSE request shall be same with that in the previous OPEN request. Be noted that this is only a hint. User daemon can close the anon_fd when receiving the CLOSE request, then it will receive another anon_fd if the cookie gets looked up. Or it can also ignore the CLOSE request, and keep writing data into the anon_fd. However the next time cookie gets looked up, the user daemon will still receive another anon_fd. Signed-off-by: Jeffle Xu --- fs/cachefiles/daemon.c | 27 +++++++++++++++++++++++++++ fs/cachefiles/interface.c | 2 ++ fs/cachefiles/internal.h | 4 ++++ include/uapi/linux/cachefiles.h | 5 +++++ 4 files changed, 38 insertions(+) diff --git a/fs/cachefiles/daemon.c b/fs/cachefiles/daemon.c index 3c3a461f8cd8..2ecfdf194206 100644 --- a/fs/cachefiles/daemon.c +++ b/fs/cachefiles/daemon.c @@ -338,6 +338,12 @@ static ssize_t cachefiles_ondemand_daemon_read(struct cachefiles_cache *cache, goto err_put_fd; } + /* CLOSE request doesn't look forward a reply */ + if (msg->opcode == CACHEFILES_OP_CLOSE) { + xa_erase(&cache->reqs, id); + complete(&req->done); + } + return n; err_put_fd: @@ -452,6 +458,19 @@ static int init_open_req(struct cachefiles_req *req, void *private) return 0; } +static int init_close_req(struct cachefiles_req *req, void *private) +{ + struct cachefiles_object *object = req->object; + struct cachefiles_close *load = (void *)req->msg.data; + int fd = object->fd; + + if (WARN_ON_ONCE(fd == -1)) + return -EIO; + + load->fd = fd; + return 0; +} + int cachefiles_ondemand_init_object(struct cachefiles_object *object) { struct fscache_cookie *cookie = object->cookie; @@ -477,6 +496,14 @@ int cachefiles_ondemand_init_object(struct cachefiles_object *object) init_open_req, NULL); } +void cachefiles_ondemand_cleanup_object(struct cachefiles_object *object) +{ + cachefiles_ondemand_send_req(object, + CACHEFILES_OP_CLOSE, + sizeof(struct cachefiles_close), + init_close_req, NULL); +} + #else static inline void cachefiles_ondemand_open(struct cachefiles_cache *cache) {} static inline void cachefiles_ondemand_release(struct cachefiles_cache *cache) {} diff --git a/fs/cachefiles/interface.c b/fs/cachefiles/interface.c index ae93cee9d25d..c5b8fefd4ccc 100644 --- a/fs/cachefiles/interface.c +++ b/fs/cachefiles/interface.c @@ -322,6 +322,8 @@ static void cachefiles_commit_object(struct cachefiles_object *object, static void cachefiles_clean_up_object(struct cachefiles_object *object, struct cachefiles_cache *cache) { + cachefiles_ondemand_cleanup_object(object); + if (test_bit(FSCACHE_COOKIE_RETIRED, &object->cookie->flags)) { if (!test_bit(CACHEFILES_OBJECT_USING_TMPFILE, &object->flags)) { cachefiles_see_object(object, cachefiles_obj_see_clean_delete); diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h index 8450ebd77949..eaac9fae74eb 100644 --- a/fs/cachefiles/internal.h +++ b/fs/cachefiles/internal.h @@ -167,6 +167,7 @@ extern const struct file_operations cachefiles_daemon_fops; #ifdef CONFIG_CACHEFILES_ONDEMAND extern int cachefiles_ondemand_init_object(struct cachefiles_object *object); +extern void cachefiles_ondemand_cleanup_object(struct cachefiles_object *object); #else static inline @@ -174,6 +175,9 @@ int cachefiles_ondemand_init_object(struct cachefiles_object *object) { return 0; } + +static inline +void cachefiles_ondemand_cleanup_object(struct cachefiles_object *object) {} #endif /* diff --git a/include/uapi/linux/cachefiles.h b/include/uapi/linux/cachefiles.h index 5ea7285863f1..47e53043cfad 100644 --- a/include/uapi/linux/cachefiles.h +++ b/include/uapi/linux/cachefiles.h @@ -8,6 +8,7 @@ enum cachefiles_opcode { CACHEFILES_OP_OPEN, + CACHEFILES_OP_CLOSE, }; /* @@ -36,4 +37,8 @@ enum cachefiles_open_flags { CACHEFILES_OPEN_WANT_CACHE_SIZE, }; +struct cachefiles_close { + __u32 fd; +}; + #endif