[mirror_ubuntu-kernels.git] / drivers / s390 / scsi / zfcp_qdio.c

/*
 * zfcp device driver
 *
 * Setup and helper functions to access QDIO.
 *
 * Copyright IBM Corporation 2002, 2008
 */

#define KMSG_COMPONENT "zfcp"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include "zfcp_ext.h"

#define QBUFF_PER_PAGE		(PAGE_SIZE / sizeof(struct qdio_buffer))

static int zfcp_qdio_buffers_enqueue(struct qdio_buffer **sbal)
{
	int pos;

	for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos += QBUFF_PER_PAGE) {
		sbal[pos] = (struct qdio_buffer *) get_zeroed_page(GFP_KERNEL);
		if (!sbal[pos])
			return -ENOMEM;
	}
	for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos++)
		if (pos % QBUFF_PER_PAGE)
			sbal[pos] = sbal[pos - 1] + 1;
	return 0;
}

static struct qdio_buffer_element *
zfcp_qdio_sbale(struct zfcp_qdio_queue *q, int sbal_idx, int sbale_idx)
{
	return &q->sbal[sbal_idx]->element[sbale_idx];
}

/**
 * zfcp_qdio_free - free memory used by request- and resposne queue
 * @adapter: pointer to the zfcp_adapter structure
 */
void zfcp_qdio_free(struct zfcp_adapter *adapter)
{
	struct qdio_buffer **sbal_req, **sbal_resp;
	int p;

	if (adapter->ccw_device)
		qdio_free(adapter->ccw_device);

	sbal_req = adapter->req_q.sbal;
	sbal_resp = adapter->resp_q.sbal;

	for (p = 0; p < QDIO_MAX_BUFFERS_PER_Q; p += QBUFF_PER_PAGE) {
		free_page((unsigned long) sbal_req[p]);
		free_page((unsigned long) sbal_resp[p]);
	}
}

static void zfcp_qdio_handler_error(struct zfcp_adapter *adapter, char *id)
{
	dev_warn(&adapter->ccw_device->dev, "A QDIO problem occurred\n");

	zfcp_erp_adapter_reopen(adapter,
				ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED |
				ZFCP_STATUS_COMMON_ERP_FAILED, id, NULL);
}

static void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt)
{
	int i, sbal_idx;

	for (i = first; i < first + cnt; i++) {
		sbal_idx = i % QDIO_MAX_BUFFERS_PER_Q;
		memset(sbal[sbal_idx], 0, sizeof(struct qdio_buffer));
	}
}

/* this needs to be called prior to updating the queue fill level */
static void zfcp_qdio_account(struct zfcp_adapter *adapter)
{
	ktime_t now;
	s64 span;
	int free, used;

	spin_lock(&adapter->qdio_stat_lock);
	now = ktime_get();
	span = ktime_us_delta(now, adapter->req_q_time);
	free = max(0, atomic_read(&adapter->req_q.count));
	used = QDIO_MAX_BUFFERS_PER_Q - free;
	adapter->req_q_util += used * span;
	adapter->req_q_time = now;
	spin_unlock(&adapter->qdio_stat_lock);
}

static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err,
			      int queue_no, int first, int count,
			      unsigned long parm)
{
	struct zfcp_adapter *adapter = (struct zfcp_adapter *) parm;
	struct zfcp_qdio_queue *queue = &adapter->req_q;

	if (unlikely(qdio_err)) {
		zfcp_hba_dbf_event_qdio(adapter, qdio_err, first, count);
		zfcp_qdio_handler_error(adapter, "qdireq1");
		return;
	}

	/* cleanup all SBALs being program-owned now */
	zfcp_qdio_zero_sbals(queue->sbal, first, count);

	zfcp_qdio_account(adapter);
	atomic_add(count, &queue->count);
	wake_up(&adapter->request_wq);
}

static void zfcp_qdio_resp_put_back(struct zfcp_adapter *adapter, int processed)
{
	struct zfcp_qdio_queue *queue = &adapter->resp_q;
	struct ccw_device *cdev = adapter->ccw_device;
	u8 count, start = queue->first;
	unsigned int retval;

	count = atomic_read(&queue->count) + processed;

	retval = do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, start, count);

	if (unlikely(retval)) {
		atomic_set(&queue->count, count);
		/* FIXME: Recover this with an adapter reopen? */
	} else {
		queue->first += count;
		queue->first %= QDIO_MAX_BUFFERS_PER_Q;
		atomic_set(&queue->count, 0);
	}
}

static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err,
			       int queue_no, int first, int count,
			       unsigned long parm)
{
	struct zfcp_adapter *adapter = (struct zfcp_adapter *) parm;
	int sbal_idx, sbal_no;

	if (unlikely(qdio_err)) {
		zfcp_hba_dbf_event_qdio(adapter, qdio_err, first, count);
		zfcp_qdio_handler_error(adapter, "qdires1");
		return;
	}

	/*
	 * go through all SBALs from input queue currently
	 * returned by QDIO layer
	 */
	for (sbal_no = 0; sbal_no < count; sbal_no++) {
		sbal_idx = (first + sbal_no) % QDIO_MAX_BUFFERS_PER_Q;
		/* go through all SBALEs of SBAL */
		zfcp_fsf_reqid_check(adapter, sbal_idx);
	}

	/*
	 * put range of SBALs back to response queue
	 * (including SBALs which have already been free before)
	 */
	zfcp_qdio_resp_put_back(adapter, count);
}

/**
 * zfcp_qdio_sbale_req - return ptr to SBALE of req_q for a struct zfcp_fsf_req
 * @fsf_req: pointer to struct fsf_req
 * Returns: pointer to qdio_buffer_element (SBALE) structure
 */
struct qdio_buffer_element *zfcp_qdio_sbale_req(struct zfcp_fsf_req *req)
{
	return zfcp_qdio_sbale(&req->adapter->req_q, req->sbal_last, 0);
}

/**
 * zfcp_qdio_sbale_curr - return curr SBALE on req_q for a struct zfcp_fsf_req
 * @fsf_req: pointer to struct fsf_req
 * Returns: pointer to qdio_buffer_element (SBALE) structure
 */
struct qdio_buffer_element *zfcp_qdio_sbale_curr(struct zfcp_fsf_req *req)
{
	return zfcp_qdio_sbale(&req->adapter->req_q, req->sbal_last,
			       req->sbale_curr);
}

static void zfcp_qdio_sbal_limit(struct zfcp_fsf_req *fsf_req, int max_sbals)
{
	int count = atomic_read(&fsf_req->adapter->req_q.count);
	count = min(count, max_sbals);
	fsf_req->sbal_limit = (fsf_req->sbal_first + count - 1)
					% QDIO_MAX_BUFFERS_PER_Q;
}

static struct qdio_buffer_element *
zfcp_qdio_sbal_chain(struct zfcp_fsf_req *fsf_req, unsigned long sbtype)
{
	struct qdio_buffer_element *sbale;

	/* set last entry flag in current SBALE of current SBAL */
	sbale = zfcp_qdio_sbale_curr(fsf_req);
	sbale->flags |= SBAL_FLAGS_LAST_ENTRY;

	/* don't exceed last allowed SBAL */
	if (fsf_req->sbal_last == fsf_req->sbal_limit)
		return NULL;

	/* set chaining flag in first SBALE of current SBAL */
	sbale = zfcp_qdio_sbale_req(fsf_req);
	sbale->flags |= SBAL_FLAGS0_MORE_SBALS;

	/* calculate index of next SBAL */
	fsf_req->sbal_last++;
	fsf_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q;

	/* keep this requests number of SBALs up-to-date */
	fsf_req->sbal_number++;

	/* start at first SBALE of new SBAL */
	fsf_req->sbale_curr = 0;

	/* set storage-block type for new SBAL */
	sbale = zfcp_qdio_sbale_curr(fsf_req);
	sbale->flags |= sbtype;

	return sbale;
}

static struct qdio_buffer_element *
zfcp_qdio_sbale_next(struct zfcp_fsf_req *fsf_req, unsigned long sbtype)
{
	if (fsf_req->sbale_curr == ZFCP_LAST_SBALE_PER_SBAL)
		return zfcp_qdio_sbal_chain(fsf_req, sbtype);
	fsf_req->sbale_curr++;
	return zfcp_qdio_sbale_curr(fsf_req);
}

static void zfcp_qdio_undo_sbals(struct zfcp_fsf_req *fsf_req)
{
	struct qdio_buffer **sbal = fsf_req->adapter->req_q.sbal;
	int first = fsf_req->sbal_first;
	int last = fsf_req->sbal_last;
	int count = (last - first + QDIO_MAX_BUFFERS_PER_Q) %
		QDIO_MAX_BUFFERS_PER_Q + 1;
	zfcp_qdio_zero_sbals(sbal, first, count);
}

static int zfcp_qdio_fill_sbals(struct zfcp_fsf_req *fsf_req,
				unsigned int sbtype, void *start_addr,
				unsigned int total_length)
{
	struct qdio_buffer_element *sbale;
	unsigned long remaining, length;
	void *addr;

	/* split segment up */
	for (addr = start_addr, remaining = total_length; remaining > 0;
	     addr += length, remaining -= length) {
		sbale = zfcp_qdio_sbale_next(fsf_req, sbtype);
		if (!sbale) {
			atomic_inc(&fsf_req->adapter->qdio_outb_full);
			zfcp_qdio_undo_sbals(fsf_req);
			return -EINVAL;
		}

		/* new piece must not exceed next page boundary */
		length = min(remaining,
			     (PAGE_SIZE - ((unsigned long)addr &
					   (PAGE_SIZE - 1))));
		sbale->addr = addr;
		sbale->length = length;
	}
	return 0;
}

/**
 * zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list
 * @fsf_req: request to be processed
 * @sbtype: SBALE flags
 * @sg: scatter-gather list
 * @max_sbals: upper bound for number of SBALs to be used
 * Returns: number of bytes, or error (negativ)
 */
int zfcp_qdio_sbals_from_sg(struct zfcp_fsf_req *fsf_req, unsigned long sbtype,
			    struct scatterlist *sg, int max_sbals)
{
	struct qdio_buffer_element *sbale;
	int retval, bytes = 0;

	/* figure out last allowed SBAL */
	zfcp_qdio_sbal_limit(fsf_req, max_sbals);

	/* set storage-block type for this request */
	sbale = zfcp_qdio_sbale_req(fsf_req);
	sbale->flags |= sbtype;

	for (; sg; sg = sg_next(sg)) {
		retval = zfcp_qdio_fill_sbals(fsf_req, sbtype, sg_virt(sg),
					      sg->length);
		if (retval < 0)
			return retval;
		bytes += sg->length;
	}

	/* assume that no other SBALEs are to follow in the same SBAL */
	sbale = zfcp_qdio_sbale_curr(fsf_req);
	sbale->flags |= SBAL_FLAGS_LAST_ENTRY;

	return bytes;
}

/**
 * zfcp_qdio_send - set PCI flag in first SBALE and send req to QDIO
 * @fsf_req: pointer to struct zfcp_fsf_req
 * Returns: 0 on success, error otherwise
 */
int zfcp_qdio_send(struct zfcp_fsf_req *fsf_req)
{
	struct zfcp_adapter *adapter = fsf_req->adapter;
	struct zfcp_qdio_queue *req_q = &adapter->req_q;
	int first = fsf_req->sbal_first;
	int count = fsf_req->sbal_number;
	int retval;
	unsigned int qdio_flags = QDIO_FLAG_SYNC_OUTPUT;

	zfcp_qdio_account(adapter);

	retval = do_QDIO(adapter->ccw_device, qdio_flags, 0, first, count);
	if (unlikely(retval)) {
		zfcp_qdio_zero_sbals(req_q->sbal, first, count);
		return retval;
	}

	/* account for transferred buffers */
	atomic_sub(count, &req_q->count);
	req_q->first += count;
	req_q->first %= QDIO_MAX_BUFFERS_PER_Q;
	return 0;
}

/**
 * zfcp_qdio_allocate - allocate queue memory and initialize QDIO data
 * @adapter: pointer to struct zfcp_adapter
 * Returns: -ENOMEM on memory allocation error or return value from
 *          qdio_allocate
 */
int zfcp_qdio_allocate(struct zfcp_adapter *adapter)
{
	struct qdio_initialize *init_data;

	if (zfcp_qdio_buffers_enqueue(adapter->req_q.sbal) ||
		   zfcp_qdio_buffers_enqueue(adapter->resp_q.sbal))
		return -ENOMEM;

	init_data = &adapter->qdio_init_data;

	init_data->cdev = adapter->ccw_device;
	init_data->q_format = QDIO_ZFCP_QFMT;
	memcpy(init_data->adapter_name, dev_name(&adapter->ccw_device->dev), 8);
	ASCEBC(init_data->adapter_name, 8);
	init_data->qib_param_field_format = 0;
	init_data->qib_param_field = NULL;
	init_data->input_slib_elements = NULL;
	init_data->output_slib_elements = NULL;
	init_data->no_input_qs = 1;
	init_data->no_output_qs = 1;
	init_data->input_handler = zfcp_qdio_int_resp;
	init_data->output_handler = zfcp_qdio_int_req;
	init_data->int_parm = (unsigned long) adapter;
	init_data->flags = QDIO_INBOUND_0COPY_SBALS |
			QDIO_OUTBOUND_0COPY_SBALS | QDIO_USE_OUTBOUND_PCIS;
	init_data->input_sbal_addr_array =
			(void **) (adapter->resp_q.sbal);
	init_data->output_sbal_addr_array =
			(void **) (adapter->req_q.sbal);

	return qdio_allocate(init_data);
}

/**
 * zfcp_close_qdio - close qdio queues for an adapter
 */
void zfcp_qdio_close(struct zfcp_adapter *adapter)
{
	struct zfcp_qdio_queue *req_q;
	int first, count;

	if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
		return;

	/* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */
	req_q = &adapter->req_q;
	spin_lock_bh(&adapter->req_q_lock);
	atomic_clear_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &adapter->status);
	spin_unlock_bh(&adapter->req_q_lock);

	qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR);

	/* cleanup used outbound sbals */
	count = atomic_read(&req_q->count);
	if (count < QDIO_MAX_BUFFERS_PER_Q) {
		first = (req_q->first + count) % QDIO_MAX_BUFFERS_PER_Q;
		count = QDIO_MAX_BUFFERS_PER_Q - count;
		zfcp_qdio_zero_sbals(req_q->sbal, first, count);
	}
	req_q->first = 0;
	atomic_set(&req_q->count, 0);
	adapter->resp_q.first = 0;
	atomic_set(&adapter->resp_q.count, 0);
}

/**
 * zfcp_qdio_open - prepare and initialize response queue
 * @adapter: pointer to struct zfcp_adapter
 * Returns: 0 on success, otherwise -EIO
 */
int zfcp_qdio_open(struct zfcp_adapter *adapter)
{
	struct qdio_buffer_element *sbale;
	int cc;

	if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)
		return -EIO;

	if (qdio_establish(&adapter->qdio_init_data))
		goto failed_establish;

	if (qdio_activate(adapter->ccw_device))
		goto failed_qdio;

	for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) {
		sbale = &(adapter->resp_q.sbal[cc]->element[0]);
		sbale->length = 0;
		sbale->flags = SBAL_FLAGS_LAST_ENTRY;
		sbale->addr = NULL;
	}

	if (do_QDIO(adapter->ccw_device, QDIO_FLAG_SYNC_INPUT, 0, 0,
		     QDIO_MAX_BUFFERS_PER_Q))
		goto failed_qdio;

	/* set index of first avalable SBALS / number of available SBALS */
	adapter->req_q.first = 0;
	atomic_set(&adapter->req_q.count, QDIO_MAX_BUFFERS_PER_Q);

	return 0;

failed_qdio:
	qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR);
failed_establish:
	dev_err(&adapter->ccw_device->dev,
		"Setting up the QDIO connection to the FCP adapter failed\n");
	return -EIO;
}
Commit	Line	Data
1da177e4	1	/*
00bab910	2	* zfcp device driver
1da177e4	3	*
00bab910	4	* Setup and helper functions to access QDIO.
1da177e4	5	*
00bab910	6	* Copyright IBM Corporation 2002, 2008
1da177e4 LT	7	*/
1da177e4 LT	8
ecf39d42 CS	9	#define KMSG_COMPONENT "zfcp"
	10	#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
	11
1da177e4 LT	12	#include "zfcp_ext.h"
1da177e4 LT	13
5d4e2262	14	#define QBUFF_PER_PAGE (PAGE_SIZE / sizeof(struct qdio_buffer))
1da177e4	15
00bab910	16	static int zfcp_qdio_buffers_enqueue(struct qdio_buffer **sbal)
1da177e4	17	{
b4e44590	18	int pos;
1da177e4	19
b4e44590	20	for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos += QBUFF_PER_PAGE) {
00bab910 SS	21	sbal[pos] = (struct qdio_buffer *) get_zeroed_page(GFP_KERNEL);
00bab910 SS	22	if (!sbal[pos])
b4e44590	23	return -ENOMEM;
b4e44590 SS	24	}
	25	for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos++)
	26	if (pos % QBUFF_PER_PAGE)
00bab910	27	sbal[pos] = sbal[pos - 1] + 1;
b4e44590	28	return 0;
1da177e4 LT	29	}
1da177e4 LT	30
44cc76f2	31	static struct qdio_buffer_element *
00bab910	32	zfcp_qdio_sbale(struct zfcp_qdio_queue *q, int sbal_idx, int sbale_idx)
1da177e4	33	{
00bab910	34	return &q->sbal[sbal_idx]->element[sbale_idx];
1da177e4 LT	35	}
1da177e4 LT	36
00bab910 SS	37	/**
	38	* zfcp_qdio_free - free memory used by request- and resposne queue
	39	* @adapter: pointer to the zfcp_adapter structure
	40	*/
	41	void zfcp_qdio_free(struct zfcp_adapter *adapter)
1da177e4	42	{
00bab910 SS	43	struct qdio_buffer sbal_req, sbal_resp;
00bab910 SS	44	int p;
1da177e4	45
00bab910 SS	46	if (adapter->ccw_device)
00bab910 SS	47	qdio_free(adapter->ccw_device);
1da177e4	48
00bab910 SS	49	sbal_req = adapter->req_q.sbal;
00bab910 SS	50	sbal_resp = adapter->resp_q.sbal;
1da177e4	51
00bab910 SS	52	for (p = 0; p < QDIO_MAX_BUFFERS_PER_Q; p += QBUFF_PER_PAGE) {
	53	free_page((unsigned long) sbal_req[p]);
	54	free_page((unsigned long) sbal_resp[p]);
	55	}
1da177e4 LT	56	}
1da177e4 LT	57
5ffd51a5	58	static void zfcp_qdio_handler_error(struct zfcp_adapter adapter, char id)
1da177e4	59	{
ff3b24fa	60	dev_warn(&adapter->ccw_device->dev, "A QDIO problem occurred\n");
1da177e4	61
00bab910 SS	62	zfcp_erp_adapter_reopen(adapter,
	63	ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED \|
	64	ZFCP_STATUS_COMMON_ERP_FAILED, id, NULL);
1da177e4 LT	65	}
1da177e4 LT	66
5d4e2262 CS	67	static void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt)
	68	{
	69	int i, sbal_idx;
	70
	71	for (i = first; i < first + cnt; i++) {
	72	sbal_idx = i % QDIO_MAX_BUFFERS_PER_Q;
	73	memset(sbal[sbal_idx], 0, sizeof(struct qdio_buffer));
	74	}
	75	}
	76
94506fd1 MP	77	/* this needs to be called prior to updating the queue fill level */
	78	static void zfcp_qdio_account(struct zfcp_adapter *adapter)
	79	{
	80	ktime_t now;
	81	s64 span;
	82	int free, used;
	83
	84	spin_lock(&adapter->qdio_stat_lock);
	85	now = ktime_get();
	86	span = ktime_us_delta(now, adapter->req_q_time);
	87	free = max(0, atomic_read(&adapter->req_q.count));
	88	used = QDIO_MAX_BUFFERS_PER_Q - free;
	89	adapter->req_q_util += used * span;
	90	adapter->req_q_time = now;
	91	spin_unlock(&adapter->qdio_stat_lock);
	92	}
	93
779e6e1c JG	94	static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err,
779e6e1c JG	95	int queue_no, int first, int count,
00bab910	96	unsigned long parm)
1da177e4	97	{
00bab910 SS	98	struct zfcp_adapter adapter = (struct zfcp_adapter ) parm;
00bab910 SS	99	struct zfcp_qdio_queue *queue = &adapter->req_q;
1da177e4	100
779e6e1c JG	101	if (unlikely(qdio_err)) {
779e6e1c JG	102	zfcp_hba_dbf_event_qdio(adapter, qdio_err, first, count);
5ffd51a5	103	zfcp_qdio_handler_error(adapter, "qdireq1");
00bab910 SS	104	return;
00bab910 SS	105	}
1da177e4 LT	106
1da177e4 LT	107	/* cleanup all SBALs being program-owned now */
00bab910	108	zfcp_qdio_zero_sbals(queue->sbal, first, count);
1da177e4	109
94506fd1	110	zfcp_qdio_account(adapter);
00bab910	111	atomic_add(count, &queue->count);
1da177e4	112	wake_up(&adapter->request_wq);
1da177e4 LT	113	}
1da177e4 LT	114
00bab910	115	static void zfcp_qdio_resp_put_back(struct zfcp_adapter *adapter, int processed)
1da177e4	116	{
00bab910 SS	117	struct zfcp_qdio_queue *queue = &adapter->resp_q;
	118	struct ccw_device *cdev = adapter->ccw_device;
	119	u8 count, start = queue->first;
	120	unsigned int retval;
1da177e4	121
00bab910 SS	122	count = atomic_read(&queue->count) + processed;
00bab910 SS	123
779e6e1c	124	retval = do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, start, count);
00bab910 SS	125
	126	if (unlikely(retval)) {
	127	atomic_set(&queue->count, count);
	128	/* FIXME: Recover this with an adapter reopen? */
	129	} else {
	130	queue->first += count;
	131	queue->first %= QDIO_MAX_BUFFERS_PER_Q;
	132	atomic_set(&queue->count, 0);
	133	}
	134	}
	135
779e6e1c JG	136	static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err,
779e6e1c JG	137	int queue_no, int first, int count,
00bab910 SS	138	unsigned long parm)
	139	{
	140	struct zfcp_adapter adapter = (struct zfcp_adapter ) parm;
bd63eaf4	141	int sbal_idx, sbal_no;
00bab910	142
779e6e1c JG	143	if (unlikely(qdio_err)) {
779e6e1c JG	144	zfcp_hba_dbf_event_qdio(adapter, qdio_err, first, count);
5ffd51a5	145	zfcp_qdio_handler_error(adapter, "qdires1");
00bab910 SS	146	return;
00bab910 SS	147	}
1da177e4	148
1da177e4 LT	149	/*
	150	* go through all SBALs from input queue currently
	151	* returned by QDIO layer
	152	*/
00bab910 SS	153	for (sbal_no = 0; sbal_no < count; sbal_no++) {
00bab910 SS	154	sbal_idx = (first + sbal_no) % QDIO_MAX_BUFFERS_PER_Q;
1da177e4	155	/* go through all SBALEs of SBAL */
bd63eaf4	156	zfcp_fsf_reqid_check(adapter, sbal_idx);
1da177e4 LT	157	}
	158
	159	/*
	160	* put range of SBALs back to response queue
	161	* (including SBALs which have already been free before)
	162	*/
00bab910	163	zfcp_qdio_resp_put_back(adapter, count);
1da177e4 LT	164	}
1da177e4 LT	165
1da177e4	166	/**
00bab910 SS	167	* zfcp_qdio_sbale_req - return ptr to SBALE of req_q for a struct zfcp_fsf_req
	168	* @fsf_req: pointer to struct fsf_req
	169	* Returns: pointer to qdio_buffer_element (SBALE) structure
1da177e4	170	*/
44cc76f2	171	struct qdio_buffer_element zfcp_qdio_sbale_req(struct zfcp_fsf_req req)
1da177e4	172	{
00bab910	173	return zfcp_qdio_sbale(&req->adapter->req_q, req->sbal_last, 0);
1da177e4 LT	174	}
	175
	176	/**
00bab910 SS	177	* zfcp_qdio_sbale_curr - return curr SBALE on req_q for a struct zfcp_fsf_req
	178	* @fsf_req: pointer to struct fsf_req
	179	* Returns: pointer to qdio_buffer_element (SBALE) structure
1da177e4	180	*/
44cc76f2	181	struct qdio_buffer_element zfcp_qdio_sbale_curr(struct zfcp_fsf_req req)
1da177e4	182	{
00bab910 SS	183	return zfcp_qdio_sbale(&req->adapter->req_q, req->sbal_last,
00bab910 SS	184	req->sbale_curr);
1da177e4 LT	185	}
1da177e4 LT	186
00bab910	187	static void zfcp_qdio_sbal_limit(struct zfcp_fsf_req *fsf_req, int max_sbals)
1da177e4	188	{
00bab910	189	int count = atomic_read(&fsf_req->adapter->req_q.count);
1da177e4	190	count = min(count, max_sbals);
00bab910 SS	191	fsf_req->sbal_limit = (fsf_req->sbal_first + count - 1)
00bab910 SS	192	% QDIO_MAX_BUFFERS_PER_Q;
1da177e4 LT	193	}
1da177e4 LT	194
44cc76f2	195	static struct qdio_buffer_element *
1da177e4 LT	196	zfcp_qdio_sbal_chain(struct zfcp_fsf_req *fsf_req, unsigned long sbtype)
1da177e4 LT	197	{
44cc76f2	198	struct qdio_buffer_element *sbale;
1da177e4 LT	199
	200	/* set last entry flag in current SBALE of current SBAL */
	201	sbale = zfcp_qdio_sbale_curr(fsf_req);
	202	sbale->flags \|= SBAL_FLAGS_LAST_ENTRY;
	203
	204	/* don't exceed last allowed SBAL */
e891bffe	205	if (fsf_req->sbal_last == fsf_req->sbal_limit)
1da177e4 LT	206	return NULL;
	207
	208	/* set chaining flag in first SBALE of current SBAL */
00bab910	209	sbale = zfcp_qdio_sbale_req(fsf_req);
1da177e4 LT	210	sbale->flags \|= SBAL_FLAGS0_MORE_SBALS;
	211
	212	/* calculate index of next SBAL */
e891bffe MP	213	fsf_req->sbal_last++;
e891bffe MP	214	fsf_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q;
1da177e4 LT	215
	216	/* keep this requests number of SBALs up-to-date */
	217	fsf_req->sbal_number++;
	218
	219	/* start at first SBALE of new SBAL */
	220	fsf_req->sbale_curr = 0;
	221
	222	/* set storage-block type for new SBAL */
	223	sbale = zfcp_qdio_sbale_curr(fsf_req);
	224	sbale->flags \|= sbtype;
	225
	226	return sbale;
	227	}
	228
44cc76f2	229	static struct qdio_buffer_element *
1da177e4 LT	230	zfcp_qdio_sbale_next(struct zfcp_fsf_req *fsf_req, unsigned long sbtype)
	231	{
	232	if (fsf_req->sbale_curr == ZFCP_LAST_SBALE_PER_SBAL)
	233	return zfcp_qdio_sbal_chain(fsf_req, sbtype);
1da177e4	234	fsf_req->sbale_curr++;
1da177e4 LT	235	return zfcp_qdio_sbale_curr(fsf_req);
	236	}
	237
00bab910	238	static void zfcp_qdio_undo_sbals(struct zfcp_fsf_req *fsf_req)
1da177e4	239	{
00bab910 SS	240	struct qdio_buffer **sbal = fsf_req->adapter->req_q.sbal;
	241	int first = fsf_req->sbal_first;
	242	int last = fsf_req->sbal_last;
	243	int count = (last - first + QDIO_MAX_BUFFERS_PER_Q) %
	244	QDIO_MAX_BUFFERS_PER_Q + 1;
	245	zfcp_qdio_zero_sbals(sbal, first, count);
1da177e4 LT	246	}
1da177e4 LT	247
00bab910 SS	248	static int zfcp_qdio_fill_sbals(struct zfcp_fsf_req *fsf_req,
	249	unsigned int sbtype, void *start_addr,
	250	unsigned int total_length)
1da177e4	251	{
44cc76f2	252	struct qdio_buffer_element *sbale;
1da177e4 LT	253	unsigned long remaining, length;
	254	void *addr;
	255
00bab910	256	/* split segment up */
1da177e4 LT	257	for (addr = start_addr, remaining = total_length; remaining > 0;
1da177e4 LT	258	addr += length, remaining -= length) {
00bab910 SS	259	sbale = zfcp_qdio_sbale_next(fsf_req, sbtype);
00bab910 SS	260	if (!sbale) {
2450d3e7	261	atomic_inc(&fsf_req->adapter->qdio_outb_full);
00bab910	262	zfcp_qdio_undo_sbals(fsf_req);
1da177e4 LT	263	return -EINVAL;
1da177e4 LT	264	}
00bab910 SS	265
00bab910 SS	266	/* new piece must not exceed next page boundary */
1da177e4	267	length = min(remaining,
00bab910	268	(PAGE_SIZE - ((unsigned long)addr &
1da177e4	269	(PAGE_SIZE - 1))));
00bab910 SS	270	sbale->addr = addr;
00bab910 SS	271	sbale->length = length;
1da177e4	272	}
00bab910	273	return 0;
1da177e4 LT	274	}
1da177e4 LT	275
1da177e4 LT	276	/**
	277	* zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list
	278	* @fsf_req: request to be processed
	279	* @sbtype: SBALE flags
	280	* @sg: scatter-gather list
1da177e4	281	* @max_sbals: upper bound for number of SBALs to be used
00bab910	282	* Returns: number of bytes, or error (negativ)
1da177e4	283	*/
00bab910 SS	284	int zfcp_qdio_sbals_from_sg(struct zfcp_fsf_req *fsf_req, unsigned long sbtype,
00bab910 SS	285	struct scatterlist *sg, int max_sbals)
1da177e4	286	{
44cc76f2	287	struct qdio_buffer_element *sbale;
00bab910	288	int retval, bytes = 0;
1da177e4 LT	289
	290	/* figure out last allowed SBAL */
	291	zfcp_qdio_sbal_limit(fsf_req, max_sbals);
	292
00bab910 SS	293	/* set storage-block type for this request */
00bab910 SS	294	sbale = zfcp_qdio_sbale_req(fsf_req);
1da177e4 LT	295	sbale->flags \|= sbtype;
1da177e4 LT	296
00bab910 SS	297	for (; sg; sg = sg_next(sg)) {
	298	retval = zfcp_qdio_fill_sbals(fsf_req, sbtype, sg_virt(sg),
	299	sg->length);
	300	if (retval < 0)
	301	return retval;
	302	bytes += sg->length;
1da177e4	303	}
00bab910	304
1da177e4 LT	305	/* assume that no other SBALEs are to follow in the same SBAL */
	306	sbale = zfcp_qdio_sbale_curr(fsf_req);
	307	sbale->flags \|= SBAL_FLAGS_LAST_ENTRY;
00bab910	308
1da177e4 LT	309	return bytes;
	310	}
	311
1da177e4	312	/**
00bab910 SS	313	* zfcp_qdio_send - set PCI flag in first SBALE and send req to QDIO
	314	* @fsf_req: pointer to struct zfcp_fsf_req
	315	* Returns: 0 on success, error otherwise
1da177e4	316	*/
00bab910	317	int zfcp_qdio_send(struct zfcp_fsf_req *fsf_req)
1da177e4	318	{
00bab910 SS	319	struct zfcp_adapter *adapter = fsf_req->adapter;
	320	struct zfcp_qdio_queue *req_q = &adapter->req_q;
	321	int first = fsf_req->sbal_first;
	322	int count = fsf_req->sbal_number;
21ddaa53 CS	323	int retval;
21ddaa53 CS	324	unsigned int qdio_flags = QDIO_FLAG_SYNC_OUTPUT;
00bab910	325
94506fd1 MP	326	zfcp_qdio_account(adapter);
94506fd1 MP	327
21ddaa53	328	retval = do_QDIO(adapter->ccw_device, qdio_flags, 0, first, count);
00bab910 SS	329	if (unlikely(retval)) {
	330	zfcp_qdio_zero_sbals(req_q->sbal, first, count);
	331	return retval;
	332	}
	333
	334	/* account for transferred buffers */
	335	atomic_sub(count, &req_q->count);
	336	req_q->first += count;
	337	req_q->first %= QDIO_MAX_BUFFERS_PER_Q;
00bab910	338	return 0;
1da177e4 LT	339	}
1da177e4 LT	340
00bab910 SS	341	/**
	342	* zfcp_qdio_allocate - allocate queue memory and initialize QDIO data
	343	* @adapter: pointer to struct zfcp_adapter
	344	* Returns: -ENOMEM on memory allocation error or return value from
	345	* qdio_allocate
	346	*/
	347	int zfcp_qdio_allocate(struct zfcp_adapter *adapter)
	348	{
	349	struct qdio_initialize *init_data;
	350
	351	if (zfcp_qdio_buffers_enqueue(adapter->req_q.sbal) \|\|
	352	zfcp_qdio_buffers_enqueue(adapter->resp_q.sbal))
	353	return -ENOMEM;
	354
	355	init_data = &adapter->qdio_init_data;
	356
	357	init_data->cdev = adapter->ccw_device;
	358	init_data->q_format = QDIO_ZFCP_QFMT;
b225cf9b	359	memcpy(init_data->adapter_name, dev_name(&adapter->ccw_device->dev), 8);
00bab910 SS	360	ASCEBC(init_data->adapter_name, 8);
	361	init_data->qib_param_field_format = 0;
	362	init_data->qib_param_field = NULL;
	363	init_data->input_slib_elements = NULL;
	364	init_data->output_slib_elements = NULL;
00bab910 SS	365	init_data->no_input_qs = 1;
	366	init_data->no_output_qs = 1;
	367	init_data->input_handler = zfcp_qdio_int_resp;
	368	init_data->output_handler = zfcp_qdio_int_req;
	369	init_data->int_parm = (unsigned long) adapter;
	370	init_data->flags = QDIO_INBOUND_0COPY_SBALS \|
	371	QDIO_OUTBOUND_0COPY_SBALS \| QDIO_USE_OUTBOUND_PCIS;
	372	init_data->input_sbal_addr_array =
	373	(void **) (adapter->resp_q.sbal);
	374	init_data->output_sbal_addr_array =
	375	(void **) (adapter->req_q.sbal);
	376
	377	return qdio_allocate(init_data);
	378	}
	379
	380	/**
	381	* zfcp_close_qdio - close qdio queues for an adapter
1da177e4	382	*/
00bab910	383	void zfcp_qdio_close(struct zfcp_adapter *adapter)
1da177e4	384	{
00bab910 SS	385	struct zfcp_qdio_queue *req_q;
	386	int first, count;
	387
44cc76f2	388	if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
00bab910 SS	389	return;
	390
	391	/* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */
	392	req_q = &adapter->req_q;
0406289e	393	spin_lock_bh(&adapter->req_q_lock);
00bab910	394	atomic_clear_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &adapter->status);
0406289e	395	spin_unlock_bh(&adapter->req_q_lock);
00bab910	396
779e6e1c	397	qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR);
00bab910 SS	398
	399	/* cleanup used outbound sbals */
	400	count = atomic_read(&req_q->count);
	401	if (count < QDIO_MAX_BUFFERS_PER_Q) {
	402	first = (req_q->first + count) % QDIO_MAX_BUFFERS_PER_Q;
	403	count = QDIO_MAX_BUFFERS_PER_Q - count;
	404	zfcp_qdio_zero_sbals(req_q->sbal, first, count);
1da177e4	405	}
00bab910 SS	406	req_q->first = 0;
00bab910 SS	407	atomic_set(&req_q->count, 0);
00bab910 SS	408	adapter->resp_q.first = 0;
00bab910 SS	409	atomic_set(&adapter->resp_q.count, 0);
1da177e4 LT	410	}
1da177e4 LT	411
00bab910 SS	412	/**
	413	* zfcp_qdio_open - prepare and initialize response queue
	414	* @adapter: pointer to struct zfcp_adapter
	415	* Returns: 0 on success, otherwise -EIO
	416	*/
	417	int zfcp_qdio_open(struct zfcp_adapter *adapter)
	418	{
44cc76f2	419	struct qdio_buffer_element *sbale;
00bab910 SS	420	int cc;
00bab910 SS	421
44cc76f2	422	if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)
00bab910 SS	423	return -EIO;
00bab910 SS	424
ff3b24fa CS	425	if (qdio_establish(&adapter->qdio_init_data))
ff3b24fa CS	426	goto failed_establish;
00bab910	427
ff3b24fa	428	if (qdio_activate(adapter->ccw_device))
00bab910	429	goto failed_qdio;
00bab910 SS	430
	431	for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) {
	432	sbale = &(adapter->resp_q.sbal[cc]->element[0]);
	433	sbale->length = 0;
	434	sbale->flags = SBAL_FLAGS_LAST_ENTRY;
	435	sbale->addr = NULL;
	436	}
	437
	438	if (do_QDIO(adapter->ccw_device, QDIO_FLAG_SYNC_INPUT, 0, 0,
ff3b24fa	439	QDIO_MAX_BUFFERS_PER_Q))
00bab910	440	goto failed_qdio;
00bab910 SS	441
	442	/* set index of first avalable SBALS / number of available SBALS */
	443	adapter->req_q.first = 0;
	444	atomic_set(&adapter->req_q.count, QDIO_MAX_BUFFERS_PER_Q);
00bab910 SS	445
	446	return 0;
	447
	448	failed_qdio:
779e6e1c	449	qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR);
ff3b24fa CS	450	failed_establish:
	451	dev_err(&adapter->ccw_device->dev,
	452	"Setting up the QDIO connection to the FCP adapter failed\n");
00bab910 SS	453	return -EIO;
00bab910 SS	454	}