From mboxrd@z Thu Jan 1 00:00:00 1970 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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4CA1BC46467 for ; Wed, 11 Jan 2023 08:32:21 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4NsLX364Q8z3cd9 for ; Wed, 11 Jan 2023 19:32:19 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.alibaba.com (client-ip=115.124.30.56; helo=out30-56.freemail.mail.aliyun.com; envelope-from=jefflexu@linux.alibaba.com; receiver=) Received: from out30-56.freemail.mail.aliyun.com (out30-56.freemail.mail.aliyun.com [115.124.30.56]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4NsLWp0nkWz3c65 for ; Wed, 11 Jan 2023 19:32:05 +1100 (AEDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R181e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045168;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0VZMQWl9_1673425921; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0VZMQWl9_1673425921) by smtp.aliyun-inc.com; Wed, 11 Jan 2023 16:32:02 +0800 From: Jingbo Xu To: xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org Subject: [PATCH v2 3/7] erofs: allocate anonymous file of blob for page cache sharing Date: Wed, 11 Jan 2023 16:31:54 +0800 Message-Id: <20230111083158.23462-4-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.19.1.6.gb485710b In-Reply-To: <20230111083158.23462-1-jefflexu@linux.alibaba.com> References: <20230111083158.23462-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linux-erofs@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development of Linux EROFS file system List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fsdevel@vger.kernel.org, huyue2@coolpad.com, linux-kernel@vger.kernel.org Errors-To: linux-erofs-bounces+linux-erofs=archiver.kernel.org@lists.ozlabs.org Sender: "Linux-erofs" In prep for the following support for page cache sharing based mmap, allocate an anonymous file of corresponding blob, so that we can link associated vma to the blob later. Signed-off-by: Jingbo Xu --- fs/erofs/fscache.c | 74 +++++++++++++++++++++++++++++++++++++++++++++ fs/erofs/internal.h | 1 + 2 files changed, 75 insertions(+) diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c index 81f96c910277..f715b3efcc77 100644 --- a/fs/erofs/fscache.c +++ b/fs/erofs/fscache.c @@ -4,6 +4,8 @@ * Copyright (C) 2022, Bytedance Inc. All rights reserved. */ #include +#include +#include #include "internal.h" static DEFINE_MUTEX(erofs_domain_list_lock); @@ -22,6 +24,11 @@ struct erofs_fscache_request { refcount_t ref; }; +struct erofs_fscache_share_file_info { + erofs_off_t pa; + pgoff_t max_idx; +}; + static struct erofs_fscache_request *erofs_fscache_req_alloc(struct address_space *mapping, loff_t start, size_t len) { @@ -316,6 +323,73 @@ const struct address_space_operations erofs_fscache_access_aops = { .readahead = erofs_fscache_readahead, }; +static int erofs_fscache_share_meta_release(struct inode *inode, struct file *filp) +{ + kfree(filp->private_data); + filp->private_data = NULL; + return 0; +} + +static const struct file_operations erofs_fscache_share_meta_fops = { + .release = erofs_fscache_share_meta_release, +}; + +static int erofs_fscache_share_file_release(struct inode *inode, struct file *filp) +{ + fput(filp->private_data); + filp->private_data = NULL; + return 0; +} + +static int erofs_fscache_share_file_open(struct inode *inode, struct file *filp) +{ + /* since page cache sharing is enabled only when i_size <= chunk_size */ + struct erofs_map_blocks map = {}; /* .m_la = 0 */ + struct erofs_map_dev mdev; + struct inode *realinode; + struct file *realfile; + struct erofs_fscache_share_file_info *finfo; + int ret; + + ret = erofs_map_blocks(inode, &map, EROFS_GET_BLOCKS_RAW); + if (ret) + return ret; + + mdev = (struct erofs_map_dev) { + .m_deviceid = map.m_deviceid, + .m_pa = map.m_pa, + }; + ret = erofs_map_dev(inode->i_sb, &mdev); + if (ret) + return ret; + + finfo = kzalloc(sizeof(struct erofs_fscache_share_file_info), GFP_KERNEL); + if (!finfo) + return -ENOMEM; + finfo->pa = mdev.m_pa; + finfo->max_idx = DIV_ROUND_UP(mdev.m_pa + inode->i_size, PAGE_SIZE); + + realinode = mdev.m_fscache->inode; + ihold(realinode); + realfile = alloc_file_pseudo(realinode, filp->f_path.mnt, "[erofs]", + O_RDONLY, &erofs_fscache_share_meta_fops); + if (IS_ERR(realfile)) { + iput(realinode); + kfree(finfo); + return PTR_ERR(realfile); + } + + realfile->private_data = finfo; + filp->private_data = realfile; + return 0; +} + +const struct file_operations erofs_fscache_share_file_fops = { + .llseek = generic_file_llseek, + .open = erofs_fscache_share_file_open, + .release = erofs_fscache_share_file_release, +}; + static void erofs_fscache_domain_put(struct erofs_domain *domain) { mutex_lock(&erofs_domain_list_lock); diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index b3d04bc2d279..7c6a7a2d9acf 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -616,6 +616,7 @@ struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb, void erofs_fscache_unregister_cookie(struct erofs_fscache *fscache); extern const struct address_space_operations erofs_fscache_access_aops; +extern const struct file_operations erofs_fscache_share_file_fops; #else static inline int erofs_fscache_register_fs(struct super_block *sb) { -- 2.19.1.6.gb485710b