From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35150) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fYmVZ-00016O-Mc for qemu-devel@nongnu.org; Fri, 29 Jun 2018 02:03:51 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fYmVY-0007GI-TT for qemu-devel@nongnu.org; Fri, 29 Jun 2018 02:03:49 -0400 From: Fam Zheng Date: Fri, 29 Jun 2018 14:03:28 +0800 Message-Id: <20180629060328.4423-4-famz@redhat.com> In-Reply-To: <20180629060328.4423-1-famz@redhat.com> References: <20180629060328.4423-1-famz@redhat.com> Subject: [Qemu-devel] [PATCH 3/3] file-posix: Fix EINTR handling List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , Max Reitz , qemu-block@nongnu.org EINTR should be checked against errno, not ret. While fixing the bug, collect the branches with a switch block. Also, change the return value from -ENOSTUP to -ENOSPC when the actual issue is request range passes EOF, which should be distinguishable from the case of error == ENOSYS by the caller, so that it could still retry with other byte ranges, whereas it shouldn't retry anymore upon ENOSYS. Signed-off-by: Fam Zheng --- block/file-posix.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/block/file-posix.c b/block/file-posix.c index 07bb061fe4..6b736f603a 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -1474,20 +1474,21 @@ static ssize_t handle_aiocb_copy_range(RawPosixAIOData *aiocb) ssize_t ret = copy_file_range(aiocb->aio_fildes, &in_off, aiocb->aio_fd2, &out_off, bytes, 0); - if (ret == -EINTR) { - continue; + if (ret == 0) { + /* No progress (e.g. when beyond EOF), let the caller fall back to + * buffer I/O. */ + return -ENOSPC; } if (ret < 0) { - if (errno == ENOSYS) { + switch (errno) { + case ENOSYS: return -ENOTSUP; - } else { + case EINTR: + continue; + default: return -errno; } } - if (!ret) { - /* No progress (e.g. when beyond EOF), fall back to buffer I/O. */ - return -ENOTSUP; - } bytes -= ret; } return 0; -- 2.17.1