From patchwork Mon May 3 16:11:03 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Josef Bacik X-Patchwork-Id: 96780 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter.kernel.org (8.14.3/8.14.3) with ESMTP id o44DoG6M014092 for ; Tue, 4 May 2010 13:50:16 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758781Ab0EDNsK (ORCPT ); Tue, 4 May 2010 09:48:10 -0400 Received: from ext-fwsm-phx2.redhat.com ([209.132.183.252]:29283 "EHLO test1244.test.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753863Ab0EDNsI (ORCPT ); Tue, 4 May 2010 09:48:08 -0400 X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter.kernel.org [140.211.167.41]); Tue, 04 May 2010 13:50:17 +0000 (UTC) X-Greylist: delayed 17399 seconds by postgrey-1.27 at vger.kernel.org; Tue, 04 May 2010 09:48:08 EDT Received: from test1244.test.redhat.com (localhost [127.0.0.1]) by test1244.test.redhat.com (8.14.3/8.14.3) with ESMTP id o43GBK5x002010; Mon, 3 May 2010 12:11:20 -0400 Received: (from root@localhost) by test1244.test.redhat.com (8.14.3/8.14.3/Submit) id o43GBKY1002008; Mon, 3 May 2010 12:11:20 -0400 From: Josef Bacik To: linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@vger.kernel.org Cc: Josef Bacik Subject: [PATCH 1/3] fs: allow short direct-io reads to be completed via buffered IO Date: Mon, 3 May 2010 12:11:03 -0400 Message-Id: <1272903065-1974-1-git-send-email-josef@redhat.com> X-Mailer: git-send-email 1.6.6.1 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org diff --git a/mm/filemap.c b/mm/filemap.c index 140ebda..cc804d9 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1263,7 +1263,7 @@ generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov, { struct file *filp = iocb->ki_filp; ssize_t retval; - unsigned long seg; + unsigned long seg = 0; size_t count; loff_t *ppos = &iocb->ki_pos; @@ -1292,19 +1292,30 @@ generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov, } if (retval > 0) *ppos = pos + retval; - if (retval) { + if (retval < 0 || !count) { file_accessed(filp); goto out; } } } + count = retval; for (seg = 0; seg < nr_segs; seg++) { read_descriptor_t desc; + loff_t offset = 0; + + if (count) { + if (count > iov[seg].iov_len) { + count -= iov[seg].iov_len; + continue; + } + offset = count; + count = 0; + } desc.written = 0; - desc.arg.buf = iov[seg].iov_base; - desc.count = iov[seg].iov_len; + desc.arg.buf = iov[seg].iov_base + offset; + desc.count = iov[seg].iov_len - offset; if (desc.count == 0) continue; desc.error = 0;