From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39035) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yy2hr-00018q-E2 for qemu-devel@nongnu.org; Thu, 28 May 2015 14:39:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Yy2ho-0003mR-7p for qemu-devel@nongnu.org; Thu, 28 May 2015 14:39:03 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51293) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yy2ho-0003mM-0Y for qemu-devel@nongnu.org; Thu, 28 May 2015 14:39:00 -0400 Date: Thu, 28 May 2015 19:38:54 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20150528183854.GA11131@work-vm> References: <555D39D2.4000705@cn.fujitsu.com> <556579A0.4060204@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <556579A0.4060204@cn.fujitsu.com> Subject: Re: [Qemu-devel] [PATCH] iov: don't touch iov in iov_send_recv() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Wen Congyang Cc: Kevin Wolf , Paolo Bonzini , qemu-devl , "Dr. David Alan Gilbert" * Wen Congyang (wency@cn.fujitsu.com) wrote: > Ping... Hi Wen, I don't know the block side of stuff to review this stuff, so I'll leave it to Kevin and Paolo. Dave > > On 05/21/2015 09:50 AM, Wen Congyang wrote: > > Signed-off-by: Wen Congyang > > --- > > include/qemu/iov.h | 2 +- > > util/iov.c | 14 +++++++++++++- > > 2 files changed, 14 insertions(+), 2 deletions(-) > > > > diff --git a/include/qemu/iov.h b/include/qemu/iov.h > > index 68d25f2..569b2c2 100644 > > --- a/include/qemu/iov.h > > +++ b/include/qemu/iov.h > > @@ -75,7 +75,7 @@ size_t iov_memset(const struct iovec *iov, const unsigned int iov_cnt, > > * For iov_send_recv() _whole_ area being sent or received > > * should be within the iovec, not only beginning of it. > > */ > > -ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, > > +ssize_t iov_send_recv(int sockfd, const struct iovec *iov, unsigned iov_cnt, > > size_t offset, size_t bytes, bool do_send); > > #define iov_recv(sockfd, iov, iov_cnt, offset, bytes) \ > > iov_send_recv(sockfd, iov, iov_cnt, offset, bytes, false) > > diff --git a/util/iov.c b/util/iov.c > > index 2fb18e6..a0d5934 100644 > > --- a/util/iov.c > > +++ b/util/iov.c > > @@ -133,7 +133,7 @@ do_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, bool do_send) > > #endif > > } > > > > -ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, > > +ssize_t iov_send_recv(int sockfd, const struct iovec *_iov, unsigned iov_cnt, > > size_t offset, size_t bytes, > > bool do_send) > > { > > @@ -141,6 +141,16 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, > > ssize_t ret; > > size_t orig_len, tail; > > unsigned niov; > > + struct iovec *local_iov, *iov; > > + > > + if (bytes <= 0) { > > + return 0; > > + } > > + > > + local_iov = g_new0(struct iovec, iov_cnt); > > + iov_copy(local_iov, iov_cnt, _iov, iov_cnt, offset, bytes); > > + offset = 0; > > + iov = local_iov; > > > > while (bytes > 0) { > > /* Find the start position, skipping `offset' bytes: > > @@ -187,6 +197,7 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, > > > > if (ret < 0) { > > assert(errno != EINTR); > > + g_free(local_iov); > > if (errno == EAGAIN && total > 0) { > > return total; > > } > > @@ -205,6 +216,7 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, > > bytes -= ret; > > } > > > > + g_free(local_iov); > > return total; > > } > > > > > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK