From patchwork Thu Aug 23 16:27:52 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peng Tao X-Patchwork-Id: 1368181 Return-Path: X-Original-To: patchwork-linux-nfs@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 8E375DF2AB for ; Thu, 23 Aug 2012 16:28:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752936Ab2HWQ2r (ORCPT ); Thu, 23 Aug 2012 12:28:47 -0400 Received: from mail-pz0-f46.google.com ([209.85.210.46]:43629 "EHLO mail-pz0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752910Ab2HWQ2r (ORCPT ); Thu, 23 Aug 2012 12:28:47 -0400 Received: by mail-pz0-f46.google.com with SMTP id y13so493174dad.19 for ; Thu, 23 Aug 2012 09:28:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; bh=wz3KJyQEVMcKe1GvHsxxM+bulzA9eeyg64rDkdekrUY=; b=oS4BCSmy/cHljBsvnA9A35JOGVLAfsmU8RP9FXd+8TX5E23kQjEsfMvTQ+CuoQfZrk 5sRtpdoX5mg9nzVvWvusMyJwGIV7/qVmRkL9G0sKz4Hk5TAV3M+GqHNqRBNsrnDs2ZcV vSbeD+xnAxvy+tbi9XzCfA6y3e8sL5F9L/sOolhcAR1wbHzp2Zc1HlVQVZYLCUTLuTKq lDjkc1UaMhWZTLNYd3PO18XNIvZWWOvOSvwZKJgn6keP3Ua6ZwQbV4Z2njD8Xg2bK+E2 WZqoe+/IjyLCDKpIWQkOWTMjmpH8jwmtu+bI2WZZ1rWg/who8Iup8YUa8goS9W44ORBs Xhgw== Received: by 10.66.72.197 with SMTP id f5mr4579074pav.20.1345739326801; Thu, 23 Aug 2012 09:28:46 -0700 (PDT) Received: from debian-sid.localdomain ([123.118.157.62]) by mx.google.com with ESMTPS id kc7sm6325160pbb.5.2012.08.23.09.28.43 (version=SSLv3 cipher=OTHER); Thu, 23 Aug 2012 09:28:46 -0700 (PDT) From: Peng Tao To: Trond.Myklebust@netapp.com Cc: linux-nfs@vger.kernel.org Subject: [PATCH-resend 5/6] pnfsblock: fix non-aligned DIO read Date: Fri, 24 Aug 2012 00:27:52 +0800 Message-Id: <1345739273-2241-6-git-send-email-bergwolf@gmail.com> X-Mailer: git-send-email 1.7.1.262.g5ef3d In-Reply-To: <1345739273-2241-1-git-send-email-bergwolf@gmail.com> References: <1345739273-2241-1-git-send-email-bergwolf@gmail.com> Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org For DIO read, if it is not sector aligned, we should reject it and resend via MDS. Otherwise there might be data corruption. Also teach bl_read_pagelist to handle partial page reads for DIO. Cc: stable [since v3.4] Signed-off-by: Peng Tao --- fs/nfs/blocklayout/blocklayout.c | 64 +++++++++++++++++++++++++++++++++----- 1 files changed, 56 insertions(+), 8 deletions(-) diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c index 39fa002..e5dfef5 100644 --- a/fs/nfs/blocklayout/blocklayout.c +++ b/fs/nfs/blocklayout/blocklayout.c @@ -252,8 +252,11 @@ bl_read_pagelist(struct nfs_read_data *rdata) sector_t isect, extent_length = 0; struct parallel_io *par; loff_t f_offset = rdata->args.offset; + size_t bytes_left = rdata->args.count; + unsigned int pg_offset, pg_len; struct page **pages = rdata->args.pages; int pg_index = rdata->args.pgbase >> PAGE_CACHE_SHIFT; + const bool is_dio = (header->dreq != NULL); dprintk("%s enter nr_pages %u offset %lld count %u\n", __func__, rdata->pages.npages, f_offset, (unsigned int)rdata->args.count); @@ -287,36 +290,53 @@ bl_read_pagelist(struct nfs_read_data *rdata) extent_length = min(extent_length, cow_length); } } + + if (is_dio) { + pg_offset = f_offset & ~PAGE_CACHE_MASK; + if (pg_offset + bytes_left > PAGE_CACHE_SIZE) + pg_len = PAGE_CACHE_SIZE - pg_offset; + else + pg_len = bytes_left; + + f_offset += pg_len; + bytes_left -= pg_len; + isect += (pg_offset >> SECTOR_SHIFT); + } else { + pg_offset = 0; + pg_len = PAGE_CACHE_SIZE; + } + hole = is_hole(be, isect); if (hole && !cow_read) { bio = bl_submit_bio(READ, bio); /* Fill hole w/ zeroes w/o accessing device */ dprintk("%s Zeroing page for hole\n", __func__); - zero_user_segment(pages[i], 0, PAGE_CACHE_SIZE); + zero_user_segment(pages[i], pg_offset, pg_len); print_page(pages[i]); SetPageUptodate(pages[i]); } else { struct pnfs_block_extent *be_read; be_read = (hole && cow_read) ? cow_read : be; - bio = bl_add_page_to_bio(bio, rdata->pages.npages - i, + bio = do_add_page_to_bio(bio, rdata->pages.npages - i, READ, isect, pages[i], be_read, - bl_end_io_read, par); + bl_end_io_read, par, + pg_offset, pg_len); if (IS_ERR(bio)) { header->pnfs_error = PTR_ERR(bio); bio = NULL; goto out; } } - isect += PAGE_CACHE_SECTORS; + isect += (pg_len >> SECTOR_SHIFT); extent_length -= PAGE_CACHE_SECTORS; } if ((isect << SECTOR_SHIFT) >= header->inode->i_size) { rdata->res.eof = 1; - rdata->res.count = header->inode->i_size - f_offset; + rdata->res.count = header->inode->i_size - rdata->args.offset; } else { - rdata->res.count = (isect << SECTOR_SHIFT) - f_offset; + rdata->res.count = (isect << SECTOR_SHIFT) - rdata->args.offset; } out: bl_put_extent(be); @@ -1149,9 +1169,37 @@ bl_clear_layoutdriver(struct nfs_server *server) return 0; } +static bool +is_aligned_req(struct nfs_page *req, unsigned int alignment) +{ + return IS_ALIGNED(req->wb_offset, alignment) && + IS_ALIGNED(req->wb_bytes, alignment); +} + +static void +bl_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req) +{ + if (pgio->pg_dreq != NULL && + !is_aligned_req(req, SECTOR_SIZE)) + nfs_pageio_reset_read_mds(pgio); + else + pnfs_generic_pg_init_read(pgio, req); +} + +static bool +bl_pg_test_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, + struct nfs_page *req) +{ + if (pgio->pg_dreq != NULL && + !is_aligned_req(req, SECTOR_SIZE)) + return false; + + return pnfs_generic_pg_test(pgio, prev, req); +} + static const struct nfs_pageio_ops bl_pg_read_ops = { - .pg_init = pnfs_generic_pg_init_read, - .pg_test = pnfs_generic_pg_test, + .pg_init = bl_pg_init_read, + .pg_test = bl_pg_test_read, .pg_doio = pnfs_generic_pg_readpages, };