Return-Path: Received: from mail-it0-f68.google.com ([209.85.214.68]:38823 "EHLO mail-it0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932130AbdGSWKV (ORCPT ); Wed, 19 Jul 2017 18:10:21 -0400 Received: by mail-it0-f68.google.com with SMTP id a62so848977itd.5 for ; Wed, 19 Jul 2017 15:10:21 -0700 (PDT) From: Trond Myklebust To: Chuck Lever , linux-nfs@vger.kernel.org Subject: [PATCH 18/20] NFS: Fix up nfs_page_group_covers_page() Date: Wed, 19 Jul 2017 18:09:53 -0400 Message-Id: <20170719220955.58210-19-trond.myklebust@primarydata.com> In-Reply-To: <20170719220955.58210-18-trond.myklebust@primarydata.com> References: <20170719220955.58210-1-trond.myklebust@primarydata.com> <20170719220955.58210-2-trond.myklebust@primarydata.com> <20170719220955.58210-3-trond.myklebust@primarydata.com> <20170719220955.58210-4-trond.myklebust@primarydata.com> <20170719220955.58210-5-trond.myklebust@primarydata.com> <20170719220955.58210-6-trond.myklebust@primarydata.com> <20170719220955.58210-7-trond.myklebust@primarydata.com> <20170719220955.58210-8-trond.myklebust@primarydata.com> <20170719220955.58210-9-trond.myklebust@primarydata.com> <20170719220955.58210-10-trond.myklebust@primarydata.com> <20170719220955.58210-11-trond.myklebust@primarydata.com> <20170719220955.58210-12-trond.myklebust@primarydata.com> <20170719220955.58210-13-trond.myklebust@primarydata.com> <20170719220955.58210-14-trond.myklebust@primarydata.com> <20170719220955.58210-15-trond.myklebust@primarydata.com> <20170719220955.58210-16-trond.myklebust@primarydata.com> <20170719220955.58210-17-trond.myklebust@primarydata.com> <20170719220955.58210-18-trond.myklebust@primarydata.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: Fix up the test in nfs_page_group_covers_page(). The simplest implementation is to check that we have a set of intersecting or contiguous subrequests that connect page offset 0 to nfs_page_length(req->wb_page). Signed-off-by: Trond Myklebust --- fs/nfs/write.c | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-) diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 0f418d825185..759e37d26acf 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -243,9 +243,6 @@ nfs_page_group_search_locked(struct nfs_page *head, unsigned int page_offset) { struct nfs_page *req; - WARN_ON_ONCE(head != head->wb_head); - WARN_ON_ONCE(!test_bit(PG_HEADLOCK, &head->wb_head->wb_flags)); - req = head; do { if (page_offset >= req->wb_pgbase && @@ -273,18 +270,15 @@ static bool nfs_page_group_covers_page(struct nfs_page *req) nfs_page_group_lock(req); - do { + for (;;) { tmp = nfs_page_group_search_locked(req->wb_head, pos); - if (tmp) { - /* no way this should happen */ - WARN_ON_ONCE(tmp->wb_pgbase != pos); - pos += tmp->wb_bytes - (pos - tmp->wb_pgbase); - } - } while (tmp && pos < len); + if (!tmp) + break; + pos = tmp->wb_pgbase + tmp->wb_bytes; + } nfs_page_group_unlock(req); - WARN_ON_ONCE(pos > len); - return pos == len; + return pos >= len; } /* We can set the PG_uptodate flag if we see that a write request -- 2.13.3