From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f182.google.com (mail-pd0-f182.google.com [209.85.192.182]) by kanga.kvack.org (Postfix) with ESMTP id A4C376B0032 for ; Mon, 5 Jan 2015 09:41:08 -0500 (EST) Received: by mail-pd0-f182.google.com with SMTP id p10so28289500pdj.13 for ; Mon, 05 Jan 2015 06:41:08 -0800 (PST) Received: from mx12.netapp.com (mx12.netapp.com. [216.240.18.77]) by mx.google.com with ESMTPS id e1si66957230pdo.117.2015.01.05.06.41.06 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 05 Jan 2015 06:41:07 -0800 (PST) Message-ID: <54AAA27C.6040906@Netapp.com> Date: Mon, 5 Jan 2015 09:41:00 -0500 From: Anna Schumaker MIME-Version: 1.0 Subject: Re: [PATCH v2 3/5] nfs: don't dirty ITER_BVEC pages read through direct I/O References: In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Omar Sandoval , Alexander Viro , Andrew Morton , Trond Myklebust , Christoph Hellwig , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Hi Omar, On 12/19/2014 10:18 PM, Omar Sandoval wrote: > As with the generic blockdev code, kernel pages shouldn't be dirtied by > the direct I/O path. > > Signed-off-by: Omar Sandoval > --- > fs/nfs/direct.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c > index 10bf072..b6ca65c 100644 > --- a/fs/nfs/direct.c > +++ b/fs/nfs/direct.c > @@ -88,6 +88,7 @@ struct nfs_direct_req { > struct pnfs_ds_commit_info ds_cinfo; /* Storage for cinfo */ > struct work_struct work; > int flags; > + int should_dirty; /* should we mark read pages dirty? */ > #define NFS_ODIRECT_DO_COMMIT (1) /* an unstable reply was received */ > #define NFS_ODIRECT_RESCHED_WRITES (2) /* write verification failed */ > struct nfs_writeverf verf; /* unstable write verifier */ Can you add should_dirty after the NFS_ODIRECT_* flags? Thanks, Anna > @@ -370,7 +371,8 @@ static void nfs_direct_read_completion(struct nfs_pgio_header *hdr) > struct nfs_page *req = nfs_list_entry(hdr->pages.next); > struct page *page = req->wb_page; > > - if (!PageCompound(page) && bytes < hdr->good_bytes) > + if (!PageCompound(page) && bytes < hdr->good_bytes && > + dreq->should_dirty) > set_page_dirty(page); > bytes += req->wb_bytes; > nfs_list_remove_request(req); > @@ -542,6 +544,7 @@ ssize_t nfs_file_direct_read(struct kiocb *iocb, struct iov_iter *iter, > dreq->inode = inode; > dreq->bytes_left = count; > dreq->ctx = get_nfs_open_context(nfs_file_open_context(iocb->ki_filp)); > + dreq->should_dirty = !iov_iter_is_bvec(iter); > l_ctx = nfs_get_lock_context(dreq->ctx); > if (IS_ERR(l_ctx)) { > result = PTR_ERR(l_ctx); > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org