2 files changed, 43 insertions, 5 deletions

diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index bb5a6e0fa49a..6b1423707397 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -63,6 +63,13 @@ static int scsi_eh_try_stu(struct scsi_cmnd *scmd);
 static enum scsi_disposition scsi_try_to_abort_cmd(struct scsi_host_template *,
 						   struct scsi_cmnd *);
 
+#ifdef CONFIG_AHCI_IMX
+extern void *sg_io_buffer_hack;
+#else
+#define sg_io_buffer_hack NULL
+#endif
+
+/* called with shost->host_lock held */
 void scsi_eh_wakeup(struct Scsi_Host *shost)
 {
 	lockdep_assert_held(shost->host_lock);
@@ -72,6 +79,11 @@ void scsi_eh_wakeup(struct Scsi_Host *shost)
 		wake_up_process(shost->ehandler);
 		SCSI_LOG_ERROR_RECOVERY(5, shost_printk(KERN_INFO, shost,
 			"Waking error handler thread\n"));
+	} else if ((shost->host_failed > 0) || (sg_io_buffer_hack != NULL)) {
+		trace_scsi_eh_wakeup(shost);
+		wake_up_process(shost->ehandler);
+		SCSI_LOG_ERROR_RECOVERY(5, shost_printk(KERN_INFO, shost,
+			"Waking error handler thread\n"));
 	}
 }
 
@@ -2242,8 +2254,15 @@ int scsi_error_handler(void *data)
 		if (kthread_should_stop())
 			break;
 
+		/*
+		 * Do not go to sleep, when there is host_failed when the
+		 * one-PRD per command workaroud is triggered.
+		 * Because that ata/scsi subsystem maybe hang, when CD_ROM
+		 * and HDD are accessed simultaneously.
+		 */
 		if ((shost->host_failed == 0 && shost->host_eh_scheduled == 0) ||
-		    shost->host_failed != scsi_host_busy(shost)) {
+		    ((shost->host_failed != scsi_host_busy(shost)) &&
+		    (sg_io_buffer_hack == NULL) && (shost->host_failed > 0))) {
 			SCSI_LOG_ERROR_RECOVERY(1,
 				shost_printk(KERN_INFO, shost,
 					     "scsi_eh_%d: sleeping\n",
diff --git a/drivers/scsi/scsi_ioctl.c b/drivers/scsi/scsi_ioctl.c
index 6e2f82152b4a..5f774b8c12be 100644
--- a/drivers/scsi/scsi_ioctl.c
+++ b/drivers/scsi/scsi_ioctl.c
@@ -370,6 +370,12 @@ static int scsi_fill_sghdr_rq(struct scsi_device *sdev, struct request *rq,
 	return 0;
 }
 
+#ifdef CONFIG_AHCI_IMX
+extern void *sg_io_buffer_hack;
+#else
+#define sg_io_buffer_hack NULL
+#endif
+
 static int scsi_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
 		struct bio *bio)
 {
@@ -401,7 +407,12 @@ static int scsi_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
 			ret = -EFAULT;
 	}
 
-	r = blk_rq_unmap_user(bio);
+	if (sg_io_buffer_hack && !hdr->iovec_count)
+		r = copy_to_user(hdr->dxferp, sg_io_buffer_hack,
+				hdr->dxfer_len);
+	else
+		r = blk_rq_unmap_user(bio);
+
 	if (!ret)
 		ret = r;
 
@@ -425,6 +436,9 @@ static int sg_io(struct scsi_device *sdev, struct gendisk *disk,
 	if (hdr->dxfer_len > (queue_max_hw_sectors(sdev->request_queue) << 9))
 		return -EIO;
 
+	if (sg_io_buffer_hack && hdr->dxfer_len > 0x10000)
+		return -EIO;
+
 	if (hdr->dxfer_len)
 		switch (hdr->dxfer_direction) {
 		default:
@@ -471,9 +485,14 @@ static int sg_io(struct scsi_device *sdev, struct gendisk *disk,
 
 		ret = blk_rq_map_user_iov(rq->q, rq, NULL, &i, GFP_KERNEL);
 		kfree(iov);
-	} else if (hdr->dxfer_len)
-		ret = blk_rq_map_user(rq->q, rq, NULL, hdr->dxferp,
-				      hdr->dxfer_len, GFP_KERNEL);
+	} else if (hdr->dxfer_len) {
+		if (sg_io_buffer_hack)
+			ret = blk_rq_map_kern(rq->q, rq, sg_io_buffer_hack,
+					hdr->dxfer_len, GFP_KERNEL);
+		else
+			ret = blk_rq_map_user(rq->q, rq, NULL, hdr->dxferp,
+					hdr->dxfer_len, GFP_KERNEL);
+	}
 
 	if (ret)
 		goto out_free_cdb;