From patchwork Thu Dec 16 16:23:27 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 12681957 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 61393C433FE for ; Thu, 16 Dec 2021 16:23:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239632AbhLPQXn (ORCPT ); Thu, 16 Dec 2021 11:23:43 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:59833 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239619AbhLPQXm (ORCPT ); Thu, 16 Dec 2021 11:23:42 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1639671822; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/ODiY9BA9iEDxke+ixUytenzlo4Pk+3ZnRR2dHYckoY=; b=cCU0gZ0iaF5Yw1PGvdJainlJ/3B3yZiCF5nMnBaekTyzPPNQxUY4DjiZUC0Oh2zLFhs0OJ YrjWK0IrPkzcTz+UxwbxryYgiK7VFbqbzCc37I5busyqPPT4I6tqmIEYXfojdz72rOWJ/O u+lZ7KhW8Do5HCJa8Tde+WUuAo6UmpQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-537-R6PWQBehMLO9Chtd3QaE-A-1; Thu, 16 Dec 2021 11:23:38 -0500 X-MC-Unique: R6PWQBehMLO9Chtd3QaE-A-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id DD50E93921; Thu, 16 Dec 2021 16:23:35 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.122]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7BCFE795B0; Thu, 16 Dec 2021 16:23:28 +0000 (UTC) Organization: Red Hat UK Ltd. 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Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH v3 62/68] 9p: Copy local writes to the cache when writing to the server From: David Howells To: linux-cachefs@redhat.com Cc: Eric Van Hensbergen , Latchesar Ionkov , Dominique Martinet , v9fs-developer@lists.sourceforge.net, dhowells@redhat.com, Trond Myklebust , Anna Schumaker , Steve French , Dominique Martinet , Jeff Layton , Matthew Wilcox , Alexander Viro , Omar Sandoval , JeffleXu , Linus Torvalds , linux-afs@lists.infradead.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, v9fs-developer@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Thu, 16 Dec 2021 16:23:27 +0000 Message-ID: <163967180760.1823006.5831751873616248910.stgit@warthog.procyon.org.uk> In-Reply-To: <163967073889.1823006.12237147297060239168.stgit@warthog.procyon.org.uk> References: <163967073889.1823006.12237147297060239168.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.23 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org When writing to the server from v9fs_vfs_writepage(), copy the data to the cache object too. To make this possible, the cookie must have its active users count incremented when the page is dirtied and kept incremented until we manage to clean up all the pages. This allows the writeback to take place after the last file struct is released. This is done by taking a use on the cookie in v9fs_set_page_dirty() if we haven't already done so (controlled by the I_PINNING_FSCACHE_WB flag) and dropping the pin in v9fs_write_inode() if __writeback_single_inode() clears all the outstanding dirty pages (conveyed by the unpinned_fscache_wb flag in the writeback_control struct). Inode eviction must also clear the flag after truncating away all the outstanding pages. In the future this will be handled more gracefully by netfslib. Changes ======= ver #3: - Canonicalise the coherency data to make it endianness-independent. ver #2: - Fix an unused-var warning due to CONFIG_9P_FSCACHE=n[1]. Signed-off-by: David Howells cc: Eric Van Hensbergen cc: Latchesar Ionkov cc: Dominique Martinet cc: v9fs-developer@lists.sourceforge.net cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/163819667027.215744.13815687931204222995.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/163906978015.143852.10646669694345706328.stgit@warthog.procyon.org.uk/ # v2 --- fs/9p/vfs_addr.c | 46 +++++++++++++++++++++++++++++++++++++++++++++- fs/9p/vfs_inode.c | 4 ++++ fs/9p/vfs_super.c | 3 +++ 3 files changed, 52 insertions(+), 1 deletion(-) diff --git a/fs/9p/vfs_addr.c b/fs/9p/vfs_addr.c index 4f5ce4aca317..f3f349f460e5 100644 --- a/fs/9p/vfs_addr.c +++ b/fs/9p/vfs_addr.c @@ -137,6 +137,7 @@ static void v9fs_vfs_readahead(struct readahead_control *ractl) static int v9fs_release_page(struct page *page, gfp_t gfp) { struct folio *folio = page_folio(page); + struct inode *inode = folio_inode(folio); if (folio_test_private(folio)) return 0; @@ -147,6 +148,7 @@ static int v9fs_release_page(struct page *page, gfp_t gfp) folio_wait_fscache(folio); } #endif + fscache_note_page_release(v9fs_inode_cookie(V9FS_I(inode))); return 1; } @@ -165,10 +167,25 @@ static void v9fs_invalidate_page(struct page *page, unsigned int offset, folio_wait_fscache(folio); } +static void v9fs_write_to_cache_done(void *priv, ssize_t transferred_or_error, + bool was_async) +{ + struct v9fs_inode *v9inode = priv; + __le32 version; + + if (IS_ERR_VALUE(transferred_or_error) && + transferred_or_error != -ENOBUFS) { + version = cpu_to_le32(v9inode->qid.version); + fscache_invalidate(v9fs_inode_cookie(v9inode), &version, + i_size_read(&v9inode->vfs_inode), 0); + } +} + static int v9fs_vfs_write_folio_locked(struct folio *folio) { struct inode *inode = folio_inode(folio); struct v9fs_inode *v9inode = V9FS_I(inode); + struct fscache_cookie *cookie = v9fs_inode_cookie(v9inode); loff_t start = folio_pos(folio); loff_t i_size = i_size_read(inode); struct iov_iter from; @@ -185,10 +202,21 @@ static int v9fs_vfs_write_folio_locked(struct folio *folio) /* We should have writeback_fid always set */ BUG_ON(!v9inode->writeback_fid); + folio_wait_fscache(folio); folio_start_writeback(folio); p9_client_write(v9inode->writeback_fid, start, &from, &err); + if (err == 0 && + fscache_cookie_enabled(cookie) && + test_bit(FSCACHE_COOKIE_IS_CACHING, &cookie->flags)) { + folio_start_fscache(folio); + fscache_write_to_cache(v9fs_inode_cookie(v9inode), + folio_mapping(folio), start, len, i_size, + v9fs_write_to_cache_done, v9inode, + true); + } + folio_end_writeback(folio); return err; } @@ -307,6 +335,7 @@ static int v9fs_write_end(struct file *filp, struct address_space *mapping, loff_t last_pos = pos + copied; struct folio *folio = page_folio(subpage); struct inode *inode = mapping->host; + struct v9fs_inode *v9inode = V9FS_I(inode); p9_debug(P9_DEBUG_VFS, "filp %p, mapping %p\n", filp, mapping); @@ -326,6 +355,7 @@ static int v9fs_write_end(struct file *filp, struct address_space *mapping, if (last_pos > inode->i_size) { inode_add_bytes(inode, last_pos - inode->i_size); i_size_write(inode, last_pos); + fscache_update_cookie(v9fs_inode_cookie(v9inode), NULL, &last_pos); } folio_mark_dirty(folio); out: @@ -335,11 +365,25 @@ static int v9fs_write_end(struct file *filp, struct address_space *mapping, return copied; } +#ifdef CONFIG_9P_FSCACHE +/* + * Mark a page as having been made dirty and thus needing writeback. We also + * need to pin the cache object to write back to. + */ +static int v9fs_set_page_dirty(struct page *page) +{ + struct v9fs_inode *v9inode = V9FS_I(page->mapping->host); + + return fscache_set_page_dirty(page, v9fs_inode_cookie(v9inode)); +} +#else +#define v9fs_set_page_dirty __set_page_dirty_nobuffers +#endif const struct address_space_operations v9fs_addr_operations = { .readpage = v9fs_vfs_readpage, .readahead = v9fs_vfs_readahead, - .set_page_dirty = __set_page_dirty_nobuffers, + .set_page_dirty = v9fs_set_page_dirty, .writepage = v9fs_vfs_writepage, .write_begin = v9fs_write_begin, .write_end = v9fs_write_end, diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c index 00366bf1ac2c..2a10242c79c7 100644 --- a/fs/9p/vfs_inode.c +++ b/fs/9p/vfs_inode.c @@ -380,8 +380,12 @@ struct inode *v9fs_get_inode(struct super_block *sb, umode_t mode, dev_t rdev) void v9fs_evict_inode(struct inode *inode) { struct v9fs_inode *v9inode = V9FS_I(inode); + __le32 version; truncate_inode_pages_final(&inode->i_data); + version = cpu_to_le32(v9inode->qid.version); + fscache_clear_inode_writeback(v9fs_inode_cookie(v9inode), inode, + &version); clear_inode(inode); filemap_fdatawrite(&inode->i_data); diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c index b739e02f5ef7..97e23b4e6982 100644 --- a/fs/9p/vfs_super.c +++ b/fs/9p/vfs_super.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include @@ -309,6 +310,7 @@ static int v9fs_write_inode(struct inode *inode, __mark_inode_dirty(inode, I_DIRTY_DATASYNC); return ret; } + fscache_unpin_writeback(wbc, v9fs_inode_cookie(v9inode)); return 0; } @@ -332,6 +334,7 @@ static int v9fs_write_inode_dotl(struct inode *inode, __mark_inode_dirty(inode, I_DIRTY_DATASYNC); return ret; } + fscache_unpin_writeback(wbc, v9fs_inode_cookie(v9inode)); return 0; }