From: Jens Axboe <axboe@suse.de>
Date: Fri, 9 Dec 2005 13:42:16 +0000 (+0100)
Subject: [SCSI] fix panic when ejecting ieee1394 ipod
X-Git-Tag: firefly_0821_release~38603^2~84^2~3
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=a8c730e85e80734412f4f73ab28496a0e8b04a7b;p=firefly-linux-kernel-4.4.55.git

[SCSI] fix panic when ejecting ieee1394 ipod

The scsi_library routines don't correctly set DMA_NONE when
req->data_len is zero (instead they check the command type first, so
if it's write, we end up with req->data_len == 0 and direction as
DMA_TO_DEVICE which confuses some drivers)

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
---

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 4afef5cdcb17..097888721ec4 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1215,12 +1215,12 @@ static int scsi_prep_fn(struct request_queue *q, struct request *req)
 		} else {
 			memcpy(cmd->cmnd, req->cmd, sizeof(cmd->cmnd));
 			cmd->cmd_len = req->cmd_len;
-			if (rq_data_dir(req) == WRITE)
+			if (!req->data_len)
+				cmd->sc_data_direction = DMA_NONE;
+			else if (rq_data_dir(req) == WRITE)
 				cmd->sc_data_direction = DMA_TO_DEVICE;
-			else if (req->data_len)
-				cmd->sc_data_direction = DMA_FROM_DEVICE;
 			else
-				cmd->sc_data_direction = DMA_NONE;
+				cmd->sc_data_direction = DMA_FROM_DEVICE;
 			
 			cmd->transfersize = req->data_len;
 			cmd->allowed = 3;