path: root/drivers/scsi/libsas/sas_scsi_host.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Serial Attached SCSI (SAS) class SCSI Host glue.
 *
 * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
 * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
 */

#include <linux/kthread.h>
#include <linux/firmware.h>
#include <linux/export.h>
#include <linux/ctype.h>
#include <linux/kernel.h>

#include "sas_internal.h"

#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsi.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_sas.h>
#include <scsi/sas_ata.h>
#include "../scsi_sas_internal.h"
#include "../scsi_transport_api.h"
#include "../scsi_priv.h"

#include <linux/err.h>
#include <linux/blkdev.h>
#include <linux/freezer.h>
#include <linux/gfp.h>
#include <linux/scatterlist.h>
#include <linux/libata.h>

/* record final status and free the task */
static void sas_end_task(struct scsi_cmnd *sc, struct sas_task *task)
{
	struct task_status_struct *ts = &task->task_status;
	int hs = 0, stat = 0;

	if (ts->resp == SAS_TASK_UNDELIVERED) {
		/* transport error */
		hs = DID_NO_CONNECT;
	} else { /* ts->resp == SAS_TASK_COMPLETE */
		/* task delivered, what happened afterwards? */
		switch (ts->stat) {
		case SAS_DEV_NO_RESPONSE:
		case SAS_INTERRUPTED:
		case SAS_PHY_DOWN:
		case SAS_NAK_R_ERR:
		case SAS_OPEN_TO:
			hs = DID_NO_CONNECT;
			break;
		case SAS_DATA_UNDERRUN:
			scsi_set_resid(sc, ts->residual);
			if (scsi_bufflen(sc) - scsi_get_resid(sc) < sc->underflow)
				hs = DID_ERROR;
			break;
		case SAS_DATA_OVERRUN:
			hs = DID_ERROR;
			break;
		case SAS_QUEUE_FULL:
			hs = DID_SOFT_ERROR; /* retry */
			break;
		case SAS_DEVICE_UNKNOWN:
			hs = DID_BAD_TARGET;
			break;
		case SAS_SG_ERR:
			hs = DID_PARITY;
			break;
		case SAS_OPEN_REJECT:
			if (ts->open_rej_reason == SAS_OREJ_RSVD_RETRY)
				hs = DID_SOFT_ERROR; /* retry */
			else
				hs = DID_ERROR;
			break;
		case SAS_PROTO_RESPONSE:
			pr_notice("LLDD:%s sent SAS_PROTO_RESP for an SSP task; please report this\n",
				  task->dev->port->ha->sas_ha_name);
			break;
		case SAS_ABORTED_TASK:
			hs = DID_ABORT;
			break;
		case SAM_STAT_CHECK_CONDITION:
			memcpy(sc->sense_buffer, ts->buf,
			       min(SCSI_SENSE_BUFFERSIZE, ts->buf_valid_size));
			stat = SAM_STAT_CHECK_CONDITION;
			break;
		default:
			stat = ts->stat;
			break;
		}
	}

	sc->result = (hs << 16) | stat;
	ASSIGN_SAS_TASK(sc, NULL);
	sas_free_task(task);
}

static void sas_scsi_task_done(struct sas_task *task)
{
	struct scsi_cmnd *sc = task->uldd_task;
	struct domain_device *dev = task->dev;
	struct sas_ha_struct *ha = dev->port->ha;
	unsigned long flags;

	spin_lock_irqsave(&dev->done_lock, flags);
	if (test_bit(SAS_HA_FROZEN, &ha->state))
		task = NULL;
	else
		ASSIGN_SAS_TASK(sc, NULL);
	spin_unlock_irqrestore(&dev->done_lock, flags);

	if (unlikely(!task)) {
		/* task will be completed by the error handler */
		pr_debug("task done but aborted\n");
		return;
	}

	if (unlikely(!sc)) {
		pr_debug("task_done called with non existing SCSI cmnd!\n");
		sas_free_task(task);
		return;
	}

	sas_end_task(sc, task);
	sc->scsi_done(sc);
}

static struct sas_task *sas_create_task(struct scsi_cmnd *cmd,
					       struct domain_device *dev,
					       gfp_t gfp_flags)
{
	struct sas_task *task = sas_alloc_task(gfp_flags);
	struct scsi_lun lun;

	if (!task)
		return NULL;

	task->uldd_task = cmd;
	ASSIGN_SAS_TASK(cmd, task);

	task->dev = dev;
	task->task_proto = task->dev->tproto; /* BUG_ON(!SSP) */

	task->ssp_task.retry_count = 1;
	int_to_scsilun(cmd->device->lun, &lun);
	memcpy(task->ssp_task.LUN, &lun.scsi_lun, 8);
	task->ssp_task.task_attr = TASK_ATTR_SIMPLE;
	task->ssp_task.cmd = cmd;

	task->scatter = scsi_sglist(cmd);
	task->num_scatter = scsi_sg_count(cmd);
	task->total_xfer_len = scsi_bufflen(cmd);
	task->data_dir = cmd->sc_data_direction;

	task->task_done = sas_scsi_task_done;

	return task;
}

int sas_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
{
	struct sas_internal *i = to_sas_internal(host->transportt);
	struct domain_device *dev = cmd_to_domain_dev(cmd);
	struct sas_task *task;
	int res = 0;

	/* If the device fell off, no sense in issuing commands */
	if (test_bit(SAS_DEV_GONE, &dev->state)) {
		cmd->result = DID_BAD_TARGET << 16;
		goto out_done;
	}

	if (dev_is_sata(dev)) {
		spin_lock_irq(dev->sata_dev.ap->lock);
		res = ata_sas_queuecmd(cmd, dev->sata_dev.ap);
		spin_unlock_irq(dev->sata_dev.ap->lock);
		return res;
	}

	task = sas_create_task(cmd, dev, GFP_ATOMIC);
	if (!task)
		return SCSI_MLQUEUE_HOST_BUSY;

	res = i->dft->lldd_execute_task(task, GFP_ATOMIC);
	if (res)
		goto out_free_task;
	return 0;

out_free_task:
	pr_debug("lldd_execute_task returned: %d\n",