From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EF142ECDE44 for ; Wed, 31 Oct 2018 23:46:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B798620664 for ; Wed, 31 Oct 2018 23:46:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="OKWs37k1" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B798620664 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728728AbeKAIHS (ORCPT ); Thu, 1 Nov 2018 04:07:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:54918 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728704AbeKAIHQ (ORCPT ); Thu, 1 Nov 2018 04:07:16 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8F2E820848; Wed, 31 Oct 2018 23:07:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1541027226; bh=34y4eytW8REGCP0YpMIKjpVLx2aLXV0OepI83a3odA8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OKWs37k1Njr8U2OYjmbUB/mJDHBACB8M+V6YcdRCPBy1yvEqqaYK6EfmhJ8g9OGjC CE2XObdYT5dzU/Rhawk1fAxcCerVc1UHxBQUiiaZVNbXr9c7YjY/rFnASUKve1Ikw1 NkftIqwklzcO2i3sWT+ORoqz3+q4z6rL2De/9LFU= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Finn Thain , "Martin K . Petersen" , Sasha Levin Subject: [PATCH AUTOSEL 4.19 092/146] scsi: esp_scsi: Track residual for PIO transfers Date: Wed, 31 Oct 2018 19:04:47 -0400 Message-Id: <20181031230541.28822-92-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181031230541.28822-1-sashal@kernel.org> References: <20181031230541.28822-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Finn Thain [ Upstream commit fd47d919d0c336e7c22862b51ee94927ffea227a ] If a target disconnects during a PIO data transfer the command may fail when the target reconnects: scsi host1: DMA length is zero! scsi host1: cur adr[04380000] len[00000000] The scsi bus is then reset. This happens because the residual reached zero before the transfer was completed. The usual residual calculation relies on the Transfer Count registers. That works for DMA transfers but not for PIO transfers. Fix the problem by storing the PIO transfer residual and using that to correctly calculate bytes_sent. Fixes: 6fe07aaffbf0 ("[SCSI] m68k: new mac_esp scsi driver") Tested-by: Stan Johnson Signed-off-by: Finn Thain Tested-by: Michael Schmitz Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/esp_scsi.c | 1 + drivers/scsi/esp_scsi.h | 2 ++ drivers/scsi/mac_esp.c | 2 ++ 3 files changed, 5 insertions(+) diff --git a/drivers/scsi/esp_scsi.c b/drivers/scsi/esp_scsi.c index c3fc34b9964d..9e5d3f7d29ae 100644 --- a/drivers/scsi/esp_scsi.c +++ b/drivers/scsi/esp_scsi.c @@ -1338,6 +1338,7 @@ static int esp_data_bytes_sent(struct esp *esp, struct esp_cmd_entry *ent, bytes_sent = esp->data_dma_len; bytes_sent -= ecount; + bytes_sent -= esp->send_cmd_residual; /* * The am53c974 has a DMA 'pecularity'. The doc states: diff --git a/drivers/scsi/esp_scsi.h b/drivers/scsi/esp_scsi.h index 8163dca2071b..a77772777a30 100644 --- a/drivers/scsi/esp_scsi.h +++ b/drivers/scsi/esp_scsi.h @@ -540,6 +540,8 @@ struct esp { void *dma; int dmarev; + + u32 send_cmd_residual; }; /* A front-end driver for the ESP chip should do the following in diff --git a/drivers/scsi/mac_esp.c b/drivers/scsi/mac_esp.c index eb551f3cc471..71879f2207e0 100644 --- a/drivers/scsi/mac_esp.c +++ b/drivers/scsi/mac_esp.c @@ -427,6 +427,8 @@ static void mac_esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count, scsi_esp_cmd(esp, ESP_CMD_TI); } } + + esp->send_cmd_residual = esp_count; } static int mac_esp_irq_pending(struct esp *esp) -- 2.17.1