From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:39196) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ScZ4A-0000RR-K3 for qemu-devel@nongnu.org; Thu, 07 Jun 2012 05:31:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ScZ40-0004Fp-FI for qemu-devel@nongnu.org; Thu, 07 Jun 2012 05:31:42 -0400 Received: from mx1.redhat.com ([209.132.183.28]:61361) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ScZ40-0004Eg-7T for qemu-devel@nongnu.org; Thu, 07 Jun 2012 05:31:32 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q579VUAM001976 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Thu, 7 Jun 2012 05:31:30 -0400 From: Gerd Hoffmann Date: Thu, 7 Jun 2012 11:30:56 +0200 Message-Id: <1339061486-28513-8-git-send-email-kraxel@redhat.com> In-Reply-To: <1339061486-28513-1-git-send-email-kraxel@redhat.com> References: <1339061486-28513-1-git-send-email-kraxel@redhat.com> Subject: [Qemu-devel] [PATCH 07/37] scsi: prepare migration code for usb-storage support List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Paolo Bonzini , Gerd Hoffmann usb-storage can't handle requests in one go as the data transfer can be splitted into lots of usb packets. Because of that there can be normal in-flight requests at savevm time and we need to handle that. With other scsi hba's this happens only in case i/o is stopped due to errors and there are pending requests which need to be restarted (req->retry = true). So, first we need to save req->retry and then handle the req->retry = false case. Write requests are handled fine already. For read requests we have to save the buffer as we will not restart the request (and thus not refill the buffer) on the target host. Cc: Paolo Bonzini Signed-off-by: Gerd Hoffmann --- hw/scsi-bus.c | 8 ++++---- hw/scsi-disk.c | 16 ++++++++++++++-- 2 files changed, 18 insertions(+), 6 deletions(-) diff --git a/hw/scsi-bus.c b/hw/scsi-bus.c index f10f3ec..4a79821 100644 --- a/hw/scsi-bus.c +++ b/hw/scsi-bus.c @@ -1507,10 +1507,9 @@ static void put_scsi_requests(QEMUFile *f, void *pv, size_t size) QTAILQ_FOREACH(req, &s->requests, next) { assert(!req->io_canceled); assert(req->status == -1); - assert(req->retry); assert(req->enqueued); - qemu_put_sbyte(f, 1); + qemu_put_sbyte(f, req->retry ? 1 : 2); qemu_put_buffer(f, req->cmd.buf, sizeof(req->cmd.buf)); qemu_put_be32s(f, &req->tag); qemu_put_be32s(f, &req->lun); @@ -1528,8 +1527,9 @@ static int get_scsi_requests(QEMUFile *f, void *pv, size_t size) { SCSIDevice *s = pv; SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, s->qdev.parent_bus); + int8_t sbyte; - while (qemu_get_sbyte(f)) { + while ((sbyte = qemu_get_sbyte(f)) > 0) { uint8_t buf[SCSI_CMD_BUF_SIZE]; uint32_t tag; uint32_t lun; @@ -1539,6 +1539,7 @@ static int get_scsi_requests(QEMUFile *f, void *pv, size_t size) qemu_get_be32s(f, &tag); qemu_get_be32s(f, &lun); req = scsi_req_new(s, tag, lun, buf, NULL); + req->retry = (sbyte == 1); if (bus->info->load_request) { req->hba_private = bus->info->load_request(f, req); } @@ -1547,7 +1548,6 @@ static int get_scsi_requests(QEMUFile *f, void *pv, size_t size) } /* Just restart it later. */ - req->retry = true; scsi_req_enqueue_internal(req); /* At this point, the request will be kept alive by the reference diff --git a/hw/scsi-disk.c b/hw/scsi-disk.c index 045c764..1691491 100644 --- a/hw/scsi-disk.c +++ b/hw/scsi-disk.c @@ -132,8 +132,14 @@ static void scsi_disk_save_request(QEMUFile *f, SCSIRequest *req) qemu_put_be64s(f, &r->sector); qemu_put_be32s(f, &r->sector_count); qemu_put_be32s(f, &r->buflen); - if (r->buflen && r->req.cmd.mode == SCSI_XFER_TO_DEV) { - qemu_put_buffer(f, r->iov.iov_base, r->iov.iov_len); + if (r->buflen) { + if (r->req.cmd.mode == SCSI_XFER_TO_DEV) { + qemu_put_buffer(f, r->iov.iov_base, r->iov.iov_len); + } else if (!req->retry) { + uint32_t len = r->iov.iov_len; + qemu_put_be32s(f, &len); + qemu_put_buffer(f, r->iov.iov_base, r->iov.iov_len); + } } } @@ -148,6 +154,12 @@ static void scsi_disk_load_request(QEMUFile *f, SCSIRequest *req) scsi_init_iovec(r, r->buflen); if (r->req.cmd.mode == SCSI_XFER_TO_DEV) { qemu_get_buffer(f, r->iov.iov_base, r->iov.iov_len); + } else if (!r->req.retry) { + uint32_t len; + qemu_get_be32s(f, &len); + r->iov.iov_len = len; + assert(r->iov.iov_len <= r->buflen); + qemu_get_buffer(f, r->iov.iov_base, r->iov.iov_len); } } -- 1.7.1