From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48960) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WsMxC-0000i5-3N for qemu-devel@nongnu.org; Wed, 04 Jun 2014 21:59:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WsMx5-0007wZ-TZ for qemu-devel@nongnu.org; Wed, 04 Jun 2014 21:58:54 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57691) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WsMx5-0007wR-MQ for qemu-devel@nongnu.org; Wed, 04 Jun 2014 21:58:47 -0400 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s551wlFG004344 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Wed, 4 Jun 2014 21:58:47 -0400 From: Fam Zheng Date: Thu, 5 Jun 2014 09:58:45 +0800 Message-Id: <1401933526-22436-8-git-send-email-famz@redhat.com> In-Reply-To: <1401933526-22436-1-git-send-email-famz@redhat.com> References: <1401933526-22436-1-git-send-email-famz@redhat.com> Subject: [Qemu-devel] [PATCH v2 7/8] virtio-blk: Convert VirtIOBlockReq.out to structrue List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , Paolo Bonzini , Stefan Hajnoczi The virtio code currently assumes that the outhdr is in its own iovec. This is not guaranteed by the spec, so we should relax this assumption. Convert the VirtIOBlockReq.out field to structrue so that we can use iov_to_buf and then discard the header from the beginning of iovec. Suggested-by: Paolo Bonzini Signed-off-by: Fam Zheng --- hw/block/virtio-blk.c | 20 ++++++++++++++------ include/hw/virtio/virtio-blk.h | 2 +- 2 files changed, 15 insertions(+), 7 deletions(-) diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index 388741e..2282e61 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -12,6 +12,7 @@ */ #include "qemu-common.h" +#include "qemu/iov.h" #include "qemu/error-report.h" #include "trace.h" #include "hw/block/block.h" @@ -81,7 +82,7 @@ static void virtio_blk_rw_complete(void *opaque, int ret) trace_virtio_blk_rw_complete(req, ret); if (ret) { - bool is_read = !(ldl_p(&req->out->type) & VIRTIO_BLK_T_OUT); + bool is_read = !(ldl_p(&req->out.type) & VIRTIO_BLK_T_OUT); if (virtio_blk_handle_rw_error(req, -ret, is_read)) return; } @@ -287,7 +288,7 @@ static void virtio_blk_handle_write(VirtIOBlockReq *req, MultiReqBuffer *mrb) BlockRequest *blkreq; uint64_t sector; - sector = ldq_p(&req->out->sector); + sector = ldq_p(&req->out.sector); bdrv_acct_start(req->dev->bs, &req->acct, req->qiov.size, BDRV_ACCT_WRITE); @@ -321,7 +322,7 @@ static void virtio_blk_handle_read(VirtIOBlockReq *req) { uint64_t sector; - sector = ldq_p(&req->out->sector); + sector = ldq_p(&req->out.sector); bdrv_acct_start(req->dev->bs, &req->acct, req->qiov.size, BDRV_ACCT_READ); @@ -344,22 +345,29 @@ static void virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb) { uint32_t type; + struct iovec *iov = req->elem->out_sg; + unsigned out_num = req->elem->out_num; if (req->elem->out_num < 1 || req->elem->in_num < 1) { error_report("virtio-blk missing headers"); exit(1); } - if (req->elem->out_sg[0].iov_len < sizeof(*req->out) || + if (req->elem->out_sg[0].iov_len < sizeof(req->out) || req->elem->in_sg[req->elem->in_num - 1].iov_len < sizeof(*req->in)) { error_report("virtio-blk header not in correct element"); exit(1); } - req->out = (void *)req->elem->out_sg[0].iov_base; + if (unlikely(iov_to_buf(iov, out_num, 0, &req->out, + sizeof(req->out)) != sizeof(req->out))) { + error_report("virtio-blk request outhdr too short"); + exit(1); + } + iov_discard_front(&iov, &out_num, sizeof(req->out)); req->in = (void *)req->elem->in_sg[req->elem->in_num - 1].iov_base; - type = ldl_p(&req->out->type); + type = ldl_p(&req->out.type); if (type & VIRTIO_BLK_T_FLUSH) { virtio_blk_handle_flush(req, mrb); diff --git a/include/hw/virtio/virtio-blk.h b/include/hw/virtio/virtio-blk.h index 1932502..df9b6f9 100644 --- a/include/hw/virtio/virtio-blk.h +++ b/include/hw/virtio/virtio-blk.h @@ -138,7 +138,7 @@ typedef struct VirtIOBlockReq { VirtIOBlock *dev; VirtQueueElement *elem; struct virtio_blk_inhdr *in; - struct virtio_blk_outhdr *out; + struct virtio_blk_outhdr out; QEMUIOVector qiov; struct VirtIOBlockReq *next; BlockAcctCookie acct; -- 2.0.0