From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47154) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1am07f-0006oL-Bp for qemu-devel@nongnu.org; Fri, 01 Apr 2016 10:32:28 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1am07c-0002G8-6r for qemu-devel@nongnu.org; Fri, 01 Apr 2016 10:32:27 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:21697 helo=relay.sw.ru) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1am07b-0002FU-Pm for qemu-devel@nongnu.org; Fri, 01 Apr 2016 10:32:24 -0400 From: "Denis V. Lunev" Date: Fri, 1 Apr 2016 17:32:09 +0300 Message-Id: <1459521130-3792-3-git-send-email-den@openvz.org> In-Reply-To: <1459521130-3792-1-git-send-email-den@openvz.org> References: <1459521130-3792-1-git-send-email-den@openvz.org> Subject: [Qemu-devel] [PATCH 2/3] ide: restart atapi dma by re-evaluating command packet List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: "Denis V. Lunev" , jsnow@redhat.com, rkagan@virtuozzo.com, Pavel Butsykin From: Pavel Butsykin ide_atapi_dma_restart() used to just complete the DMA with an error, under the assumption that there isn't enough information to restart it. However, as the contents of the ->io_buffer is preserved, it looks safe to just re-evaluate it and dispatch the ATAPI command again. Signed-off-by: Pavel Butsykin Reviewed-by: Roman Kagan Signed-off-by: Denis V. Lunev --- hw/ide/atapi.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/hw/ide/atapi.c b/hw/ide/atapi.c index 1fe58ab..acc52cd 100644 --- a/hw/ide/atapi.c +++ b/hw/ide/atapi.c @@ -488,14 +488,13 @@ static void ide_atapi_cmd_read(IDEState *s, int lba, int nb_sectors, void ide_atapi_dma_restart(IDEState *s) { /* - * I'm not sure we have enough stored to restart the command - * safely, so give the guest an error it should recover from. - * I'm assuming most guests will try to recover from something - * listed as a medium error on a CD; it seems to work on Linux. - * This would be more of a problem if we did any other type of - * DMA operation. + * At this point we can just re-evaluate the packet command and start over. + * The presence of ->dma_cb callback in the pre_save ensures that the packet + * command has been completely sent and we can safely restart command. */ - ide_atapi_cmd_error(s, MEDIUM_ERROR, ASC_NO_SEEK_COMPLETE); + s->unit = s->bus->retry_unit; + s->bus->dma->ops->restart_dma(s->bus->dma); + ide_atapi_cmd(s); } static inline uint8_t ide_atapi_set_profile(uint8_t *buf, uint8_t *index, -- 2.1.4