From patchwork Wed Jan 11 08:31:52 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 13096254 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 CD04FC5479D for ; Wed, 11 Jan 2023 08:32:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235719AbjAKIcL (ORCPT ); Wed, 11 Jan 2023 03:32:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47910 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235731AbjAKIcJ (ORCPT ); Wed, 11 Jan 2023 03:32:09 -0500 Received: from out30-6.freemail.mail.aliyun.com (out30-6.freemail.mail.aliyun.com [115.124.30.6]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 028EFA188; Wed, 11 Jan 2023 00:32:05 -0800 (PST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R231e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046049;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0VZMeLov_1673425919; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0VZMeLov_1673425919) by smtp.aliyun-inc.com; Wed, 11 Jan 2023 16:32:00 +0800 From: Jingbo Xu To: xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org Cc: huyue2@coolpad.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v2 1/7] erofs: remove unused device mapping in the meta routine Date: Wed, 11 Jan 2023 16:31:52 +0800 Message-Id: <20230111083158.23462-2-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 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Currently there're two anonymous inodes (inode and anon_inode in struct erofs_fscache) may be used for each blob. The former is only for bootstrap and used as the address_space of page cache, while the latter is used for both bootstrap and data blobs when share domain mode enabled and behaves as a sentinel in the shared domain. In prep for the following support for page cache sharing, following patch will unify these two anonymous inodes. That is, the unified anonymous inode not only acts as the address_space of page cache, but also a sentinel in share domain mode. However the current meta routine can't work if above change applied. Current meta routine will make a device mapping, and superblock of the filesystem is required to do the device mapping. Currently the superblock is derived from the input meta folio, which is reasonable since the anonymous inode (used for the address_space of page cache) is always allocated from the filesystem's sb. However after anonymous inodes are unified, that is no longer always true. For example, in share domain mode, the unified anonymous inode will be allocated from pseudo mnt, and the superblock derived from the folio is actually a pseudo sb, which can't be used for the device mapping at all. As for the meta routine itself, currently metadata is always on bootstrap, which means device mapping is not needed so far. After removing the redundant device mapping logic, we can derive the required fscache_ctx from anonymous inode's i_private. Signed-off-by: Jingbo Xu --- fs/erofs/fscache.c | 17 ++++------------- 1 file changed, 4 insertions(+), 13 deletions(-) diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c index 014e20962376..03de4dc99302 100644 --- a/fs/erofs/fscache.c +++ b/fs/erofs/fscache.c @@ -164,18 +164,8 @@ static int erofs_fscache_read_folios_async(struct fscache_cookie *cookie, static int erofs_fscache_meta_read_folio(struct file *data, struct folio *folio) { int ret; - struct super_block *sb = folio_mapping(folio)->host->i_sb; + struct erofs_fscache *ctx = folio_mapping(folio)->host->i_private; struct erofs_fscache_request *req; - struct erofs_map_dev mdev = { - .m_deviceid = 0, - .m_pa = folio_pos(folio), - }; - - ret = erofs_map_dev(sb, &mdev); - if (ret) { - folio_unlock(folio); - return ret; - } req = erofs_fscache_req_alloc(folio_mapping(folio), folio_pos(folio), folio_size(folio)); @@ -184,8 +174,8 @@ static int erofs_fscache_meta_read_folio(struct file *data, struct folio *folio) return PTR_ERR(req); } - ret = erofs_fscache_read_folios_async(mdev.m_fscache->cookie, - req, mdev.m_pa, folio_size(folio)); + ret = erofs_fscache_read_folios_async(ctx->cookie, req, + folio_pos(folio), folio_size(folio)); if (ret) req->error = ret; @@ -469,6 +459,7 @@ struct erofs_fscache *erofs_fscache_acquire_cookie(struct super_block *sb, inode->i_size = OFFSET_MAX; inode->i_mapping->a_ops = &erofs_fscache_meta_aops; mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS); + inode->i_private = ctx; ctx->inode = inode; } From patchwork Wed Jan 11 08:31:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 13096253 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 A582EC46467 for ; Wed, 11 Jan 2023 08:32:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235843AbjAKIcK (ORCPT ); Wed, 11 Jan 2023 03:32:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47928 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235829AbjAKIcH (ORCPT ); Wed, 11 Jan 2023 03:32:07 -0500 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 8507AC77E; Wed, 11 Jan 2023 00:32:04 -0800 (PST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R161e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046049;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0VZMeLpU_1673425920; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0VZMeLpU_1673425920) by smtp.aliyun-inc.com; Wed, 11 Jan 2023 16:32:01 +0800 From: Jingbo Xu To: xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org Cc: huyue2@coolpad.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v2 2/7] erofs: unify anonymous inodes for blob Date: Wed, 11 Jan 2023 16:31:53 +0800 Message-Id: <20230111083158.23462-3-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 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Currently only bootstrap will allocate anonymous inode for the address_space of page cache. In prep for the following support for page cache sharing, as the first step, always allocate anonymous inode for this use for both bootstrap and data blobs. Since now anonymous inode is also allocated for data blobs, release these anonymous inodes when .put_super() is called, or we'll get "VFS: Busy inodes after unmount." warning. Similarly, the fscache contexts for data blobs are initialized prior to the root inode, thus .kill_sb() shall also contain the cleanup routine, so that these fscache contexts can be cleaned up when mount fails while root inode has not been initialized yet. Also remove the redundant set_nlink() when initializing anonymous inode, since i_nlink has already been initialized to 1 when the inode gets allocated. Until then there're two anonymous inodes (inode and anon_inode in struct erofs_fscache) may be used for each blob. The former is used as the address_space of page cache, while the latter is used as a sentinel in the shared domain. In prep for the following support for page cache sharing, unify these two anonymous inodes. Signed-off-by: Jingbo Xu --- fs/erofs/fscache.c | 103 ++++++++++++++++++++------------------------ fs/erofs/internal.h | 6 +-- fs/erofs/super.c | 2 + 3 files changed, 51 insertions(+), 60 deletions(-) diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c index 03de4dc99302..81f96c910277 100644 --- a/fs/erofs/fscache.c +++ b/fs/erofs/fscache.c @@ -318,8 +318,6 @@ const struct address_space_operations erofs_fscache_access_aops = { static void erofs_fscache_domain_put(struct erofs_domain *domain) { - if (!domain) - return; mutex_lock(&erofs_domain_list_lock); if (refcount_dec_and_test(&domain->ref)) { list_del(&domain->list); @@ -423,12 +421,13 @@ static int erofs_fscache_register_domain(struct super_block *sb) static struct erofs_fscache *erofs_fscache_acquire_cookie(struct super_block *sb, - char *name, - unsigned int flags) + char *name) { struct fscache_volume *volume = EROFS_SB(sb)->volume; struct erofs_fscache *ctx; struct fscache_cookie *cookie; + struct super_block *psb; + struct inode *inode; int ret; ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); @@ -442,33 +441,28 @@ struct erofs_fscache *erofs_fscache_acquire_cookie(struct super_block *sb, ret = -EINVAL; goto err; } - fscache_use_cookie(cookie, false); - ctx->cookie = cookie; - - if (flags & EROFS_REG_COOKIE_NEED_INODE) { - struct inode *const inode = new_inode(sb); - - if (!inode) { - erofs_err(sb, "failed to get anon inode for %s", name); - ret = -ENOMEM; - goto err_cookie; - } - - set_nlink(inode, 1); - inode->i_size = OFFSET_MAX; - inode->i_mapping->a_ops = &erofs_fscache_meta_aops; - mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS); - inode->i_private = ctx; - ctx->inode = inode; + psb = EROFS_SB(sb)->domain_id ? erofs_pseudo_mnt->mnt_sb : sb; + inode = new_inode(psb); + if (!inode) { + erofs_err(sb, "failed to get anon inode for %s", name); + ret = -ENOMEM; + goto err_cookie; } + inode->i_size = OFFSET_MAX; + inode->i_mapping->a_ops = &erofs_fscache_meta_aops; + mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS); + inode->i_private = ctx; + + ctx->cookie = cookie; + ctx->inode = inode; return ctx; err_cookie: - fscache_unuse_cookie(ctx->cookie, NULL, NULL); - fscache_relinquish_cookie(ctx->cookie, false); + fscache_unuse_cookie(cookie, NULL, NULL); + fscache_relinquish_cookie(cookie, false); err: kfree(ctx); return ERR_PTR(ret); @@ -485,38 +479,34 @@ static void erofs_fscache_relinquish_cookie(struct erofs_fscache *ctx) static struct erofs_fscache *erofs_fscache_domain_init_cookie(struct super_block *sb, - char *name, - unsigned int flags) + char *name) { - int err; - struct inode *inode; struct erofs_fscache *ctx; struct erofs_domain *domain = EROFS_SB(sb)->domain; - ctx = erofs_fscache_acquire_cookie(sb, name, flags); + ctx = erofs_fscache_acquire_cookie(sb, name); if (IS_ERR(ctx)) return ctx; ctx->name = kstrdup(name, GFP_KERNEL); if (!ctx->name) { - err = -ENOMEM; - goto out; + erofs_fscache_relinquish_cookie(ctx); + return ERR_PTR(-ENOMEM); } - inode = new_inode(erofs_pseudo_mnt->mnt_sb); - if (!inode) { - err = -ENOMEM; - goto out; - } + /* + * In share domain scenarios, the unified anonymous inode is not only + * used as the address_space of shared page cache, but also a sentinel + * in pseudo mount. The initial refcount is used for the former and + * will be killed when the cookie finally gets relinquished. For the + * latter, the refcount is increased every time the cookie in the domain + * gets referred to. + */ + igrab(ctx->inode); ctx->domain = domain; - ctx->anon_inode = inode; - inode->i_private = ctx; refcount_inc(&domain->ref); return ctx; -out: - erofs_fscache_relinquish_cookie(ctx); - return ERR_PTR(err); } static @@ -547,7 +537,7 @@ struct erofs_fscache *erofs_domain_register_cookie(struct super_block *sb, return ctx; } spin_unlock(&psb->s_inode_list_lock); - ctx = erofs_fscache_domain_init_cookie(sb, name, flags); + ctx = erofs_fscache_domain_init_cookie(sb, name); mutex_unlock(&erofs_domain_cookies_lock); return ctx; } @@ -558,7 +548,7 @@ struct erofs_fscache *erofs_fscache_register_cookie(struct super_block *sb, { if (EROFS_SB(sb)->domain_id) return erofs_domain_register_cookie(sb, name, flags); - return erofs_fscache_acquire_cookie(sb, name, flags); + return erofs_fscache_acquire_cookie(sb, name); } void erofs_fscache_unregister_cookie(struct erofs_fscache *ctx) @@ -568,18 +558,20 @@ void erofs_fscache_unregister_cookie(struct erofs_fscache *ctx) if (!ctx) return; - domain = ctx->domain; - if (domain) { - mutex_lock(&erofs_domain_cookies_lock); - drop = atomic_read(&ctx->anon_inode->i_count) == 1; - iput(ctx->anon_inode); - mutex_unlock(&erofs_domain_cookies_lock); - if (!drop) - return; - } - erofs_fscache_relinquish_cookie(ctx); - erofs_fscache_domain_put(domain); + if (!ctx->domain) + return erofs_fscache_relinquish_cookie(ctx); + + domain = ctx->domain; + mutex_lock(&erofs_domain_cookies_lock); + /* drop the ref for the sentinel in pseudo mount */ + iput(ctx->inode); + drop = atomic_read(&ctx->inode->i_count) == 1; + if (drop) + erofs_fscache_relinquish_cookie(ctx); + mutex_unlock(&erofs_domain_cookies_lock); + if (drop) + erofs_fscache_domain_put(domain); } int erofs_fscache_register_fs(struct super_block *sb) @@ -587,7 +579,7 @@ int erofs_fscache_register_fs(struct super_block *sb) int ret; struct erofs_sb_info *sbi = EROFS_SB(sb); struct erofs_fscache *fscache; - unsigned int flags; + unsigned int flags = 0; if (sbi->domain_id) ret = erofs_fscache_register_domain(sb); @@ -606,7 +598,6 @@ int erofs_fscache_register_fs(struct super_block *sb) * * Acquired domain/volume will be relinquished in kill_sb() on error. */ - flags = EROFS_REG_COOKIE_NEED_INODE; if (sbi->domain_id) flags |= EROFS_REG_COOKIE_NEED_NOEXIST; fscache = erofs_fscache_register_cookie(sb, sbi->fsid, flags); diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index bb8501c0ff5b..b3d04bc2d279 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -108,8 +108,7 @@ struct erofs_domain { struct erofs_fscache { struct fscache_cookie *cookie; - struct inode *inode; - struct inode *anon_inode; + struct inode *inode; /* anonymous indoe for the blob */ struct erofs_domain *domain; char *name; }; @@ -604,8 +603,7 @@ static inline int z_erofs_load_lzma_config(struct super_block *sb, #endif /* !CONFIG_EROFS_FS_ZIP */ /* flags for erofs_fscache_register_cookie() */ -#define EROFS_REG_COOKIE_NEED_INODE 1 -#define EROFS_REG_COOKIE_NEED_NOEXIST 2 +#define EROFS_REG_COOKIE_NEED_NOEXIST 1 /* fscache.c */ #ifdef CONFIG_EROFS_FS_ONDEMAND diff --git a/fs/erofs/super.c b/fs/erofs/super.c index 626a615dafc2..835b69c9511b 100644 --- a/fs/erofs/super.c +++ b/fs/erofs/super.c @@ -969,6 +969,8 @@ static void erofs_put_super(struct super_block *sb) iput(sbi->packed_inode); sbi->packed_inode = NULL; #endif + erofs_free_dev_context(sbi->devs); + sbi->devs = NULL; erofs_fscache_unregister_fs(sb); } From patchwork Wed Jan 11 08:31:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 13096255 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 3600DC54EBE for ; Wed, 11 Jan 2023 08:32:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235912AbjAKIcQ (ORCPT ); Wed, 11 Jan 2023 03:32:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48026 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235868AbjAKIcL (ORCPT ); Wed, 11 Jan 2023 03:32:11 -0500 Received: from out30-131.freemail.mail.aliyun.com (out30-131.freemail.mail.aliyun.com [115.124.30.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AE248A1A7; Wed, 11 Jan 2023 00:32:07 -0800 (PST) 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 Cc: huyue2@coolpad.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.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 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org 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) { From patchwork Wed Jan 11 08:31:55 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 13096257 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 93E66C46467 for ; Wed, 11 Jan 2023 08:32:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236136AbjAKIcm (ORCPT ); Wed, 11 Jan 2023 03:32:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48110 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230074AbjAKIcP (ORCPT ); Wed, 11 Jan 2023 03:32:15 -0500 Received: from out30-7.freemail.mail.aliyun.com (out30-7.freemail.mail.aliyun.com [115.124.30.7]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E804EBC9F; Wed, 11 Jan 2023 00:32:07 -0800 (PST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R721e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046050;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0VZMek6i_1673425922; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0VZMek6i_1673425922) by smtp.aliyun-inc.com; Wed, 11 Jan 2023 16:32:03 +0800 From: Jingbo Xu To: xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org Cc: huyue2@coolpad.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v2 4/7] erofs: implement .read_iter for page cache sharing Date: Wed, 11 Jan 2023 16:31:55 +0800 Message-Id: <20230111083158.23462-5-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 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org When page cache sharing enabled, page caches are managed in the address space of blobs rather than erofs inodes. All erofs inodes sharing one chunk will refer to and share the page cache in the blob's address space. Signed-off-by: Jingbo Xu --- fs/erofs/fscache.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c index f715b3efcc77..4075d9519a7d 100644 --- a/fs/erofs/fscache.c +++ b/fs/erofs/fscache.c @@ -384,8 +384,56 @@ static int erofs_fscache_share_file_open(struct inode *inode, struct file *filp) return 0; } +static ssize_t erofs_fscache_share_file_read_iter(struct kiocb *iocb, + struct iov_iter *to) +{ + struct file *filp = iocb->ki_filp; + struct inode *inode = file_inode(filp); + struct file *realfile = filp->private_data; + struct inode *realinode = file_inode(realfile); + struct erofs_fscache_share_file_info *finfo = realfile->private_data; + ssize_t already_read = 0; + int ret = 0; + + /* no need taking (shared) inode lock since it's a ro filesystem */ + if (!iov_iter_count(to)) + return 0; + + if (IS_DAX(inode) || iocb->ki_flags & IOCB_DIRECT) + return -EOPNOTSUPP; + + do { + struct folio *folio; + size_t bytes, copied, offset, fsize; + pgoff_t index = (finfo->pa + iocb->ki_pos) >> PAGE_SHIFT; + + folio = read_cache_folio(realinode->i_mapping, index, NULL, NULL); + if (IS_ERR(folio)) { + ret = PTR_ERR(folio); + break; + } + + fsize = folio_size(folio); + offset = iocb->ki_pos & (fsize - 1); + bytes = min_t(size_t, inode->i_size - iocb->ki_pos, iov_iter_count(to)); + bytes = min_t(size_t, bytes, fsize - offset); + copied = copy_folio_to_iter(folio, offset, bytes, to); + folio_put(folio); + iocb->ki_pos += copied; + already_read += copied; + if (copied < bytes) { + ret = -EFAULT; + break; + } + } while (iov_iter_count(to) && iocb->ki_pos < inode->i_size); + + file_accessed(filp); + return already_read ? already_read : ret; +} + const struct file_operations erofs_fscache_share_file_fops = { .llseek = generic_file_llseek, + .read_iter = erofs_fscache_share_file_read_iter, .open = erofs_fscache_share_file_open, .release = erofs_fscache_share_file_release, }; From patchwork Wed Jan 11 08:31:56 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 13096258 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 44BF0C5479D for ; Wed, 11 Jan 2023 08:33:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236182AbjAKIcn (ORCPT ); Wed, 11 Jan 2023 03:32:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48150 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236015AbjAKIcP (ORCPT ); Wed, 11 Jan 2023 03:32:15 -0500 Received: from out30-7.freemail.mail.aliyun.com (out30-7.freemail.mail.aliyun.com [115.124.30.7]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 33C353897; Wed, 11 Jan 2023 00:32:08 -0800 (PST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R811e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046056;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0VZMek7P_1673425923; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0VZMek7P_1673425923) by smtp.aliyun-inc.com; Wed, 11 Jan 2023 16:32:04 +0800 From: Jingbo Xu To: xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org Cc: huyue2@coolpad.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v2 5/7] erofs: implement .mmap for page cache sharing Date: Wed, 11 Jan 2023 16:31:56 +0800 Message-Id: <20230111083158.23462-6-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 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org In mmap(2), replace vma->vm_file with the anonymous file associated with the blob, so that the vma will be linked to the address_space of the blob. One thing worth noting is that, we return error early in mmap(2) if users attempt to map beyond the file size. Normally filesystems won't restrict this in mmap(2). The checking is done in the fault handler, and SIGBUS will be signaled to users if they actually attempt to access the area beyond the end of the file. However since vma->vm_file has been changed to the anonymous file in mmap(2), we can no way derive the file size of the original file. As file size is immutable in ro filesystem, let's fail early in mmap(2) in this case. Signed-off-by: Jingbo Xu --- fs/erofs/fscache.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c index 4075d9519a7d..e3a65041c9b8 100644 --- a/fs/erofs/fscache.c +++ b/fs/erofs/fscache.c @@ -431,9 +431,40 @@ static ssize_t erofs_fscache_share_file_read_iter(struct kiocb *iocb, return already_read ? already_read : ret; } +vm_fault_t erofs_fscache_share_fault(struct vm_fault *vmf) +{ + struct file *realfile = vmf->vma->vm_file; + struct erofs_fscache_share_file_info *finfo = realfile->private_data; + pgoff_t index = vmf->pgoff; + + if (unlikely(index >= finfo->max_idx)) + return VM_FAULT_SIGBUS; + + return filemap_fault(vmf); +} + +static const struct vm_operations_struct erofs_fscache_share_file_vm_ops = { + .fault = erofs_fscache_share_fault, +}; + +static int erofs_fscache_share_file_mmap(struct file *file, + struct vm_area_struct *vma) +{ + struct file *realfile = file->private_data; + struct erofs_fscache_share_file_info *finfo = realfile->private_data; + + vma_set_file(vma, realfile); + vma->vm_pgoff = (finfo->pa >> PAGE_SHIFT) + vma->vm_pgoff; + vma->vm_ops = &erofs_fscache_share_file_vm_ops; + + file_accessed(file); + return 0; +} + const struct file_operations erofs_fscache_share_file_fops = { .llseek = generic_file_llseek, .read_iter = erofs_fscache_share_file_read_iter, + .mmap = erofs_fscache_share_file_mmap, .open = erofs_fscache_share_file_open, .release = erofs_fscache_share_file_release, }; From patchwork Wed Jan 11 08:31:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 13096256 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 E4471C5479D for ; Wed, 11 Jan 2023 08:32:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236053AbjAKIcY (ORCPT ); Wed, 11 Jan 2023 03:32:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48108 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235982AbjAKIcO (ORCPT ); Wed, 11 Jan 2023 03:32:14 -0500 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 69443AE66; Wed, 11 Jan 2023 00:32:08 -0800 (PST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R111e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046050;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0VZMSm9k_1673425924; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0VZMSm9k_1673425924) by smtp.aliyun-inc.com; Wed, 11 Jan 2023 16:32:05 +0800 From: Jingbo Xu To: xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org Cc: huyue2@coolpad.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v2 6/7] erofs: add helper checking if page cache sharing shall be enabled Date: Wed, 11 Jan 2023 16:31:57 +0800 Message-Id: <20230111083158.23462-7-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 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Erofs supports chunk deduplication to reduce disk usage. Furthermore we can make inodes share page cache of these deduplicated chunks to reduce the memory usage. This shall be much usable in container scenarios as deduplication is requisite for container image. This can be achieved by managing page cache of deduplicated chunks in blob's address space. In this way, all inodes sharing the deduplicated chunk will refer to and share the page cache in the blob's address space. So far there are some restrictions for enabling this feature. The page cache sharing feature also supports .mmap(). The reverse mapping requires that one vma can not be shared among inodes and can be linked to only one inode. As the vma will be finally linked to the blob's address space when page cache sharing enabled, the restriction of the reverse mapping actually requires that the mapped file area can not be mapped to multiple blobs. Thus page cache sharing can only be enabled for those files mapped to one blob. The chunk based data layout guarantees that a chunk will not cross the device (blob) boundary. Thus in chunk based data layout, those files smaller than the chunk size shall be guaranteed to be mapped to one blob. As chunk size is tunable at a per-file basis, this restriction can be relaxed at image building phase. As long as we ensure that the file can not be deduplicated, the file's chunk size can be set to a reasonable value larger than the file size, so that the page cache sharing feature can be enabled on this file later. The second restriction is that EROFS_BLKSIZ mus be multiples of PAGE_SIZE to avoid data leakage. Otherwise unrelated data may be exposed at the end of the last page, since file's data is arranged in unit of EROFS_BLKSIZ in the image. Considering all these restrictions, add a helper checking if page cache sharing shall be enabled for specific file. Signed-off-by: Jingbo Xu --- fs/erofs/internal.h | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index 7c6a7a2d9acf..adf6be08b47c 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -368,6 +368,29 @@ static inline unsigned int erofs_inode_datalayout(unsigned int value) EROFS_I_DATALAYOUT_BITS); } +static inline bool erofs_can_share_page(struct inode *inode) +{ + struct erofs_inode *vi = EROFS_I(inode); + struct erofs_sb_info *sbi = EROFS_SB(inode->i_sb); + + /* enable page cache sharing only in share domain mode */ + if (!erofs_is_fscache_mode(inode->i_sb) || !sbi->domain_id) + return false; + + if (vi->datalayout != EROFS_INODE_CHUNK_BASED) + return false; + + /* avoid crossing multi devicces/blobs */ + if (inode->i_size > 1UL << vi->chunkbits) + return false; + + /* avoid data leakage in mmap routine */ + if (EROFS_BLKSIZ % PAGE_SIZE) + return false; + + return true; +} + /* * Different from grab_cache_page_nowait(), reclaiming is never triggered * when allocating new pages. From patchwork Wed Jan 11 08:31:58 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 13096259 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 47C85C46467 for ; Wed, 11 Jan 2023 08:34:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238426AbjAKIdt (ORCPT ); Wed, 11 Jan 2023 03:33:49 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48362 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231889AbjAKIdJ (ORCPT ); Wed, 11 Jan 2023 03:33:09 -0500 Received: from out30-6.freemail.mail.aliyun.com (out30-6.freemail.mail.aliyun.com [115.124.30.6]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B6FCCD109; Wed, 11 Jan 2023 00:32:14 -0800 (PST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R161e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046049;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0VZMeLr-_1673425925; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0VZMeLr-_1673425925) by smtp.aliyun-inc.com; Wed, 11 Jan 2023 16:32:06 +0800 From: Jingbo Xu To: xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org Cc: huyue2@coolpad.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v2 7/7] erofs: introduce 'sharecache' mount option Date: Wed, 11 Jan 2023 16:31:58 +0800 Message-Id: <20230111083158.23462-8-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 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Introduce 'sharecache' mount option to enable page cache sharing in fscache mode. Signed-off-by: Jingbo Xu --- Documentation/filesystems/erofs.rst | 2 ++ fs/erofs/inode.c | 4 ++++ fs/erofs/internal.h | 4 ++++ fs/erofs/super.c | 13 +++++++++++++ 4 files changed, 23 insertions(+) diff --git a/Documentation/filesystems/erofs.rst b/Documentation/filesystems/erofs.rst index 958cad2c4997..1fe38323a1bb 100644 --- a/Documentation/filesystems/erofs.rst +++ b/Documentation/filesystems/erofs.rst @@ -123,6 +123,8 @@ fsid=%s Specify a filesystem image ID for Fscache back-end. domain_id=%s Specify a domain ID for Fscache back-end. The blob images are shared among filesystem instances in the same domain. +(no)sharecache Enable page cache sharing among filesystem instances in + the same domain. =================== ========================================================= Sysfs Entries diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c index d3b8736fa124..31d3ab8443d1 100644 --- a/fs/erofs/inode.c +++ b/fs/erofs/inode.c @@ -262,6 +262,10 @@ static int erofs_fill_inode(struct inode *inode) inode->i_op = &erofs_generic_iops; if (erofs_inode_is_data_compressed(vi->datalayout)) inode->i_fop = &generic_ro_fops; +#ifdef CONFIG_EROFS_FS_ONDEMAND + else if (erofs_can_share_page(inode)) + inode->i_fop = &erofs_fscache_share_file_fops; +#endif else inode->i_fop = &erofs_file_fops; break; diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index adf6be08b47c..c3ac6d613eb1 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -181,6 +181,7 @@ struct erofs_sb_info { #define EROFS_MOUNT_POSIX_ACL 0x00000020 #define EROFS_MOUNT_DAX_ALWAYS 0x00000040 #define EROFS_MOUNT_DAX_NEVER 0x00000080 +#define EROFS_MOUNT_SHARE_CACHE 0x00000100 #define clear_opt(opt, option) ((opt)->mount_opt &= ~EROFS_MOUNT_##option) #define set_opt(opt, option) ((opt)->mount_opt |= EROFS_MOUNT_##option) @@ -373,6 +374,9 @@ static inline bool erofs_can_share_page(struct inode *inode) struct erofs_inode *vi = EROFS_I(inode); struct erofs_sb_info *sbi = EROFS_SB(inode->i_sb); + if (!test_opt(&sbi->opt, SHARE_CACHE)) + return false; + /* enable page cache sharing only in share domain mode */ if (!erofs_is_fscache_mode(inode->i_sb) || !sbi->domain_id) return false; diff --git a/fs/erofs/super.c b/fs/erofs/super.c index 835b69c9511b..d05346d34ed8 100644 --- a/fs/erofs/super.c +++ b/fs/erofs/super.c @@ -456,6 +456,7 @@ enum { Opt_device, Opt_fsid, Opt_domain_id, + Opt_sharecache, Opt_err }; @@ -482,6 +483,7 @@ static const struct fs_parameter_spec erofs_fs_parameters[] = { fsparam_string("device", Opt_device), fsparam_string("fsid", Opt_fsid), fsparam_string("domain_id", Opt_domain_id), + fsparam_flag_no("sharecache", Opt_sharecache), {} }; @@ -590,9 +592,16 @@ static int erofs_fc_parse_param(struct fs_context *fc, if (!ctx->domain_id) return -ENOMEM; break; + case Opt_sharecache: + if (result.boolean) + set_opt(&ctx->opt, SHARE_CACHE); + else + clear_opt(&ctx->opt, SHARE_CACHE); + break; #else case Opt_fsid: case Opt_domain_id: + case Opt_sharecache: errorfc(fc, "%s option not supported", erofs_fs_parameters[opt].name); break; #endif @@ -1108,6 +1117,10 @@ static int erofs_show_options(struct seq_file *seq, struct dentry *root) seq_printf(seq, ",fsid=%s", sbi->fsid); if (sbi->domain_id) seq_printf(seq, ",domain_id=%s", sbi->domain_id); + if (test_opt(opt, SHARE_CACHE)) + seq_puts(seq, ",sharecache"); + else + seq_puts(seq, ",nosharecache"); #endif return 0; }