From patchwork Wed Jan 20 16:59:48 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Coddington X-Patchwork-Id: 12032943 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E507DC433E0 for ; Wed, 20 Jan 2021 17:05:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B7E6422CE3 for ; Wed, 20 Jan 2021 17:05:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391250AbhATRFT (ORCPT ); Wed, 20 Jan 2021 12:05:19 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:50016 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391641AbhATRBf (ORCPT ); Wed, 20 Jan 2021 12:01:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1611161999; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=OtOrA4Ys6J1Bm2BQBSBbJM8oiwkdvUMixkAPEQdoyU8=; b=LVo+HrhkW4+adRoLBSWxDt56udxlpD2nI5zzGJ1/2m/O0in+Cjoan1e2/jXtxQQP0nIdFD trrZLEBG8I7yqsXhw0v1BsYxq3sQuYapkVTiQN2pWu/dQ9iqWwHdP2cXPBsb8B1lf2THgP /HbxGk2Mz92V5fEtSPcJE2qkFxPadwk= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-482-5HBUKXXdOwuanCod0c_NVA-1; Wed, 20 Jan 2021 11:59:56 -0500 X-MC-Unique: 5HBUKXXdOwuanCod0c_NVA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 398838735C3 for ; Wed, 20 Jan 2021 16:59:55 +0000 (UTC) Received: from bcodding.csb (ovpn-64-66.rdu2.redhat.com [10.10.64.66]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0BC5560D11 for ; Wed, 20 Jan 2021 16:59:55 +0000 (UTC) Received: by bcodding.csb (Postfix, from userid 24008) id A09E810E3EF8; Wed, 20 Jan 2021 11:59:54 -0500 (EST) From: Benjamin Coddington To: linux-nfs@vger.kernel.org Subject: [PATCH v1 04/10] NFS: Keep the readdir pagecache cursor updated Date: Wed, 20 Jan 2021 11:59:48 -0500 Message-Id: In-Reply-To: References: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Whenever we successfully locate our dir_cookie within the pagecache, or finish emitting entries to userspace, update the pagecache cursor. These updates provide marker points to validate pagecache pages in a future patch. Signed-off-by: Benjamin Coddington --- fs/nfs/dir.c | 29 +++++++++++++++++++++++++---- 1 file changed, 25 insertions(+), 4 deletions(-) diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 6626aff9f54d..7f6c84c8a412 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -150,6 +150,10 @@ struct nfs_cache_array { struct nfs_cache_array_entry array[]; }; +static const int cache_entries_per_page = + (PAGE_SIZE - sizeof(struct nfs_cache_array)) / + sizeof(struct nfs_cache_array_entry); + struct nfs_readdir_descriptor { struct file *file; struct page *page; @@ -251,6 +255,21 @@ static bool nfs_readdir_array_is_full(struct nfs_cache_array *array) return array->page_full; } +static void nfs_readdir_set_cursor(struct nfs_readdir_descriptor *desc, int index) +{ + desc->pgc.entry_index = index; + desc->pgc.index_cookie = desc->dir_cookie; +} + +static void nfs_readdir_cursor_next(struct nfs_dir_page_cursor *pgc, u64 cookie) +{ + pgc->index_cookie = cookie; + if (++pgc->entry_index == cache_entries_per_page) { + pgc->entry_index = 0; + pgc->page_index++; + } +} + /* * the caller is responsible for freeing qstr.name * when called by nfs_readdir_add_to_array, the strings will be freed in @@ -424,7 +443,7 @@ static int nfs_readdir_search_for_pos(struct nfs_cache_array *array, index = (unsigned int)diff; desc->dir_cookie = array->array[index].cookie; - desc->pgc.entry_index = index; + nfs_readdir_set_cursor(desc, index); return 0; out_eof: desc->eof = true; @@ -492,7 +511,7 @@ static int nfs_readdir_search_for_cookie(struct nfs_cache_array *array, else desc->ctx->pos = new_pos; desc->prev_index = new_pos; - desc->pgc.entry_index = i; + nfs_readdir_set_cursor(desc, i); return 0; } } @@ -519,9 +538,9 @@ static int nfs_readdir_search_array(struct nfs_readdir_descriptor *desc) status = nfs_readdir_search_for_cookie(array, desc); if (status == -EAGAIN) { - desc->pgc.index_cookie = array->last_cookie; + desc->pgc.entry_index = array->size - 1; + nfs_readdir_cursor_next(&desc->pgc, array->last_cookie); desc->current_index += array->size; - desc->pgc.page_index++; } kunmap_atomic(array); return status; @@ -1035,6 +1054,8 @@ static void nfs_do_filldir(struct nfs_readdir_descriptor *desc) desc->eof = true; kunmap(desc->page); + desc->pgc.entry_index = i-1; + nfs_readdir_cursor_next(&desc->pgc, desc->dir_cookie); dfprintk(DIRCACHE, "NFS: nfs_do_filldir() filling ended @ cookie %llu\n", (unsigned long long)desc->dir_cookie); }