[linux-2.6-block.git] / drivers / s390 / scsi / zfcp_qdio.c

/*
 * zfcp device driver
 *
 * Setup and helper functions to access QDIO.
 *
 * Copyright IBM Corporation 2002, 2009
 */

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

#include <linux/slab.h>
#include "zfcp_ext.h"
#include "zfcp_qdio.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 void zfcp_qdio_handler_error(struct zfcp_qdio *qdio, char *id)
{
	struct zfcp_adapter *adapter = qdio->adapter;

	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 inline void zfcp_qdio_account(struct zfcp_qdio *qdio)
{
	unsigned long long now, span;
	int free, used;

	spin_lock(&qdio->stat_lock);
	now = get_clock_monotonic();
	span = (now - qdio->req_q_time) >> 12;
	free = atomic_read(&qdio->req_q.count);
	used = QDIO_MAX_BUFFERS_PER_Q - free;
	qdio->req_q_util += used * span;
	qdio->req_q_time = now;
	spin_unlock(&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_qdio *qdio = (struct zfcp_qdio *) parm;
	struct zfcp_qdio_queue *queue = &qdio->req_q;

	if (unlikely(qdio_err)) {
		zfcp_dbf_hba_qdio(qdio->adapter->dbf, qdio_err, first,
					count);
		zfcp_qdio_handler_error(qdio, "qdireq1");
		return;
	}

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

	zfcp_qdio_account(qdio);
	atomic_add(count, &queue->count);
	wake_up(&qdio->req_q_wq);
}

static void zfcp_qdio_resp_put_back(struct zfcp_qdio *qdio, int processed)
{
	struct zfcp_qdio_queue *queue = &qdio->resp_q;
	struct ccw_device *cdev = qdio->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);
		zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdrpb_1", NULL);
	} 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_qdio *qdio = (struct zfcp_qdio *) parm;
	int sbal_idx, sbal_no;

	if (unlikely(qdio_err)) {
		zfcp_dbf_hba_qdio(qdio->adapter->dbf, qdio_err, first,
					count);
		zfcp_qdio_handler_error(qdio, "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(qdio, sbal_idx);
	}

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

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

static struct qdio_buffer_element *
zfcp_qdio_sbal_chain(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req,
		     unsigned long sbtype)
{
	struct qdio_buffer_element *sbale;

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

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

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

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

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

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

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

	return sbale;
}

static struct qdio_buffer_element *
zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req,
		     unsigned int sbtype)
{
	if (q_req->sbale_curr == ZFCP_LAST_SBALE_PER_SBAL)
		return zfcp_qdio_sbal_chain(qdio, q_req, sbtype);
	q_req->sbale_curr++;
	return zfcp_qdio_sbale_curr(qdio, q_req);
}

static void zfcp_qdio_undo_sbals(struct zfcp_qdio *qdio,
				 struct zfcp_qdio_req *q_req)
{
	struct qdio_buffer **sbal = qdio->req_q.sbal;
	int first = q_req->sbal_first;
	int last = q_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_qdio *qdio,
				struct zfcp_qdio_req *q_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(qdio, q_req, sbtype);
		if (!sbale) {
			atomic_inc(&qdio->req_q_full);
			zfcp_qdio_undo_sbals(qdio, q_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_qdio *qdio, struct zfcp_qdio_req *q_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(qdio, q_req, max_sbals);

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

	for (; sg; sg = sg_next(sg)) {
		retval = zfcp_qdio_fill_sbals(qdio, q_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(qdio, q_req);
	sbale->flags |= SBAL_FLAGS_LAST_ENTRY;

	return bytes;
}

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

	zfcp_qdio_account(qdio);

	retval = do_QDIO(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;
}


static void zfcp_qdio_setup_init_data(struct qdio_initialize *id,
				      struct zfcp_qdio *qdio)
{

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

}
/**
 * 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
 */
static int zfcp_qdio_allocate(struct zfcp_qdio *qdio)
{
	struct qdio_initialize init_data;

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

	zfcp_qdio_setup_init_data(&init_data, qdio);

	return qdio_allocate(&init_data);
}

/**
 * zfcp_close_qdio - close qdio queues for an adapter
 * @qdio: pointer to structure zfcp_qdio
 */
void zfcp_qdio_close(struct zfcp_qdio *qdio)
{
	struct zfcp_qdio_queue *req_q;
	int first, count;

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

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

	qdio_shutdown(qdio->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);
	qdio->resp_q.first = 0;
	atomic_set(&qdio->resp_q.count, 0);
}

/**
 * zfcp_qdio_open - prepare and initialize response queue
 * @qdio: pointer to struct zfcp_qdio
 * Returns: 0 on success, otherwise -EIO
 */
int zfcp_qdio_open(struct zfcp_qdio *qdio)
{
	struct qdio_buffer_element *sbale;
	struct qdio_initialize init_data;
	struct ccw_device *cdev = qdio->adapter->ccw_device;
	int cc;

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

	zfcp_qdio_setup_init_data(&init_data, qdio);

	if (qdio_establish(&init_data))
		goto failed_establish;

	if (qdio_activate(cdev))
		goto failed_qdio;

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

	if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, 0,
		     QDIO_MAX_BUFFERS_PER_Q))
		goto failed_qdio;

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

	return 0;

failed_qdio:
	qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR);
failed_establish:
	dev_err(&cdev->dev,
		"Setting up the QDIO connection to the FCP adapter failed\n");
	return -EIO;
}

void zfcp_qdio_destroy(struct zfcp_qdio *qdio)
{
	struct qdio_buffer **sbal_req, **sbal_resp;
	int p;

	if (!qdio)
		return;

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

	sbal_req = qdio->req_q.sbal;
	sbal_resp = qdio->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]);
	}

	kfree(qdio);
}

int zfcp_qdio_setup(struct zfcp_adapter *adapter)
{
	struct zfcp_qdio *qdio;

	qdio = kzalloc(sizeof(struct zfcp_qdio), GFP_KERNEL);
	if (!qdio)
		return -ENOMEM;

	qdio->adapter = adapter;

	if (zfcp_qdio_allocate(qdio)) {
		zfcp_qdio_destroy(qdio);
		return -ENOMEM;
	}

	spin_lock_init(&qdio->req_q_lock);
	spin_lock_init(&qdio->stat_lock);

	adapter->qdio = qdio;
	return 0;
}
Commit	Line	Data
1da177e4	1	/*
00bab910	2	* zfcp device driver
1da177e4	3	*
00bab910	4	* Setup and helper functions to access QDIO.
1da177e4	5	*
42428f74	6	* Copyright IBM Corporation 2002, 2009
1da177e4 LT	7	*/
1da177e4 LT	8
ecf39d42 CS	9	#define KMSG_COMPONENT "zfcp"
	10	#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
	11
5a0e3ad6	12	#include <linux/slab.h>
1da177e4	13	#include "zfcp_ext.h"
34c2b712	14	#include "zfcp_qdio.h"
1da177e4	15
5d4e2262	16	#define QBUFF_PER_PAGE (PAGE_SIZE / sizeof(struct qdio_buffer))
1da177e4	17
00bab910	18	static int zfcp_qdio_buffers_enqueue(struct qdio_buffer **sbal)
1da177e4	19	{
b4e44590	20	int pos;
1da177e4	21
b4e44590	22	for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos += QBUFF_PER_PAGE) {
00bab910 SS	23	sbal[pos] = (struct qdio_buffer *) get_zeroed_page(GFP_KERNEL);
00bab910 SS	24	if (!sbal[pos])
b4e44590	25	return -ENOMEM;
b4e44590 SS	26	}
	27	for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos++)
	28	if (pos % QBUFF_PER_PAGE)
00bab910	29	sbal[pos] = sbal[pos - 1] + 1;
b4e44590	30	return 0;
1da177e4 LT	31	}
1da177e4 LT	32
564e1c86	33	static void zfcp_qdio_handler_error(struct zfcp_qdio qdio, char id)
1da177e4	34	{
564e1c86 SS	35	struct zfcp_adapter *adapter = qdio->adapter;
564e1c86 SS	36
ff3b24fa	37	dev_warn(&adapter->ccw_device->dev, "A QDIO problem occurred\n");
1da177e4	38
00bab910 SS	39	zfcp_erp_adapter_reopen(adapter,
	40	ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED \|
	41	ZFCP_STATUS_COMMON_ERP_FAILED, id, NULL);
1da177e4 LT	42	}
1da177e4 LT	43
5d4e2262 CS	44	static void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt)
	45	{
	46	int i, sbal_idx;
	47
	48	for (i = first; i < first + cnt; i++) {
	49	sbal_idx = i % QDIO_MAX_BUFFERS_PER_Q;
	50	memset(sbal[sbal_idx], 0, sizeof(struct qdio_buffer));
	51	}
	52	}
	53
94506fd1	54	/* this needs to be called prior to updating the queue fill level */
41e05a12	55	static inline void zfcp_qdio_account(struct zfcp_qdio *qdio)
94506fd1	56	{
41e05a12	57	unsigned long long now, span;
94506fd1 MP	58	int free, used;
94506fd1 MP	59
564e1c86	60	spin_lock(&qdio->stat_lock);
41e05a12 HC	61	now = get_clock_monotonic();
	62	span = (now - qdio->req_q_time) >> 12;
	63	free = atomic_read(&qdio->req_q.count);
94506fd1	64	used = QDIO_MAX_BUFFERS_PER_Q - free;
564e1c86 SS	65	qdio->req_q_util += used * span;
	66	qdio->req_q_time = now;
	67	spin_unlock(&qdio->stat_lock);
94506fd1 MP	68	}
94506fd1 MP	69
779e6e1c JG	70	static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err,
779e6e1c JG	71	int queue_no, int first, int count,
00bab910	72	unsigned long parm)
1da177e4	73	{
564e1c86 SS	74	struct zfcp_qdio qdio = (struct zfcp_qdio ) parm;
564e1c86 SS	75	struct zfcp_qdio_queue *queue = &qdio->req_q;
1da177e4	76
779e6e1c	77	if (unlikely(qdio_err)) {
5771710b SS	78	zfcp_dbf_hba_qdio(qdio->adapter->dbf, qdio_err, first,
5771710b SS	79	count);
564e1c86	80	zfcp_qdio_handler_error(qdio, "qdireq1");
00bab910 SS	81	return;
00bab910 SS	82	}
1da177e4 LT	83
1da177e4 LT	84	/* cleanup all SBALs being program-owned now */
00bab910	85	zfcp_qdio_zero_sbals(queue->sbal, first, count);
1da177e4	86
564e1c86	87	zfcp_qdio_account(qdio);
00bab910	88	atomic_add(count, &queue->count);
564e1c86	89	wake_up(&qdio->req_q_wq);
1da177e4 LT	90	}
1da177e4 LT	91
564e1c86	92	static void zfcp_qdio_resp_put_back(struct zfcp_qdio *qdio, int processed)
1da177e4	93	{
564e1c86 SS	94	struct zfcp_qdio_queue *queue = &qdio->resp_q;
564e1c86 SS	95	struct ccw_device *cdev = qdio->adapter->ccw_device;
00bab910 SS	96	u8 count, start = queue->first;
00bab910 SS	97	unsigned int retval;
1da177e4	98
00bab910 SS	99	count = atomic_read(&queue->count) + processed;
00bab910 SS	100
779e6e1c	101	retval = do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, start, count);
00bab910 SS	102
	103	if (unlikely(retval)) {
	104	atomic_set(&queue->count, count);
452b505c	105	zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdrpb_1", NULL);
00bab910 SS	106	} else {
	107	queue->first += count;
	108	queue->first %= QDIO_MAX_BUFFERS_PER_Q;
	109	atomic_set(&queue->count, 0);
	110	}
	111	}
	112
779e6e1c JG	113	static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err,
779e6e1c JG	114	int queue_no, int first, int count,
00bab910 SS	115	unsigned long parm)
00bab910 SS	116	{
564e1c86	117	struct zfcp_qdio qdio = (struct zfcp_qdio ) parm;
bd63eaf4	118	int sbal_idx, sbal_no;
00bab910	119
779e6e1c	120	if (unlikely(qdio_err)) {
5771710b SS	121	zfcp_dbf_hba_qdio(qdio->adapter->dbf, qdio_err, first,
5771710b SS	122	count);
564e1c86	123	zfcp_qdio_handler_error(qdio, "qdires1");
00bab910 SS	124	return;
00bab910 SS	125	}
1da177e4	126
1da177e4 LT	127	/*
	128	* go through all SBALs from input queue currently
	129	* returned by QDIO layer
	130	*/
00bab910 SS	131	for (sbal_no = 0; sbal_no < count; sbal_no++) {
00bab910 SS	132	sbal_idx = (first + sbal_no) % QDIO_MAX_BUFFERS_PER_Q;
1da177e4	133	/* go through all SBALEs of SBAL */
564e1c86	134	zfcp_fsf_reqid_check(qdio, sbal_idx);
1da177e4 LT	135	}
	136
	137	/*
	138	* put range of SBALs back to response queue
	139	* (including SBALs which have already been free before)
	140	*/
564e1c86	141	zfcp_qdio_resp_put_back(qdio, count);
1da177e4 LT	142	}
1da177e4 LT	143
564e1c86	144	static void zfcp_qdio_sbal_limit(struct zfcp_qdio *qdio,
34c2b712	145	struct zfcp_qdio_req *q_req, int max_sbals)
1da177e4	146	{
564e1c86	147	int count = atomic_read(&qdio->req_q.count);
1da177e4	148	count = min(count, max_sbals);
42428f74	149	q_req->sbal_limit = (q_req->sbal_first + count - 1)
00bab910	150	% QDIO_MAX_BUFFERS_PER_Q;
1da177e4 LT	151	}
1da177e4 LT	152
44cc76f2	153	static struct qdio_buffer_element *
34c2b712	154	zfcp_qdio_sbal_chain(struct zfcp_qdio qdio, struct zfcp_qdio_req q_req,
42428f74	155	unsigned long sbtype)
1da177e4	156	{
44cc76f2	157	struct qdio_buffer_element *sbale;
1da177e4 LT	158
1da177e4 LT	159	/* set last entry flag in current SBALE of current SBAL */
564e1c86	160	sbale = zfcp_qdio_sbale_curr(qdio, q_req);
1da177e4 LT	161	sbale->flags \|= SBAL_FLAGS_LAST_ENTRY;
	162
	163	/* don't exceed last allowed SBAL */
42428f74	164	if (q_req->sbal_last == q_req->sbal_limit)
1da177e4 LT	165	return NULL;
	166
	167	/* set chaining flag in first SBALE of current SBAL */
564e1c86	168	sbale = zfcp_qdio_sbale_req(qdio, q_req);
1da177e4 LT	169	sbale->flags \|= SBAL_FLAGS0_MORE_SBALS;
	170
	171	/* calculate index of next SBAL */
42428f74 SS	172	q_req->sbal_last++;
42428f74 SS	173	q_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q;
1da177e4 LT	174
1da177e4 LT	175	/* keep this requests number of SBALs up-to-date */
42428f74	176	q_req->sbal_number++;
1da177e4 LT	177
1da177e4 LT	178	/* start at first SBALE of new SBAL */
42428f74	179	q_req->sbale_curr = 0;
1da177e4 LT	180
1da177e4 LT	181	/* set storage-block type for new SBAL */
564e1c86	182	sbale = zfcp_qdio_sbale_curr(qdio, q_req);
1da177e4 LT	183	sbale->flags \|= sbtype;
	184
	185	return sbale;
	186	}
	187
44cc76f2	188	static struct qdio_buffer_element *
34c2b712	189	zfcp_qdio_sbale_next(struct zfcp_qdio qdio, struct zfcp_qdio_req q_req,
42428f74	190	unsigned int sbtype)
1da177e4	191	{
42428f74	192	if (q_req->sbale_curr == ZFCP_LAST_SBALE_PER_SBAL)
564e1c86	193	return zfcp_qdio_sbal_chain(qdio, q_req, sbtype);
42428f74	194	q_req->sbale_curr++;
564e1c86	195	return zfcp_qdio_sbale_curr(qdio, q_req);
1da177e4 LT	196	}
1da177e4 LT	197
564e1c86	198	static void zfcp_qdio_undo_sbals(struct zfcp_qdio *qdio,
34c2b712	199	struct zfcp_qdio_req *q_req)
1da177e4	200	{
564e1c86	201	struct qdio_buffer **sbal = qdio->req_q.sbal;
42428f74 SS	202	int first = q_req->sbal_first;
42428f74 SS	203	int last = q_req->sbal_last;
00bab910 SS	204	int count = (last - first + QDIO_MAX_BUFFERS_PER_Q) %
	205	QDIO_MAX_BUFFERS_PER_Q + 1;
	206	zfcp_qdio_zero_sbals(sbal, first, count);
1da177e4 LT	207	}
1da177e4 LT	208
564e1c86	209	static int zfcp_qdio_fill_sbals(struct zfcp_qdio *qdio,
34c2b712	210	struct zfcp_qdio_req *q_req,
00bab910 SS	211	unsigned int sbtype, void *start_addr,
00bab910 SS	212	unsigned int total_length)
1da177e4	213	{
44cc76f2	214	struct qdio_buffer_element *sbale;
1da177e4 LT	215	unsigned long remaining, length;
	216	void *addr;
	217
00bab910	218	/* split segment up */
1da177e4 LT	219	for (addr = start_addr, remaining = total_length; remaining > 0;
1da177e4 LT	220	addr += length, remaining -= length) {
564e1c86	221	sbale = zfcp_qdio_sbale_next(qdio, q_req, sbtype);
00bab910	222	if (!sbale) {
564e1c86 SS	223	atomic_inc(&qdio->req_q_full);
564e1c86 SS	224	zfcp_qdio_undo_sbals(qdio, q_req);
1da177e4 LT	225	return -EINVAL;
1da177e4 LT	226	}
00bab910 SS	227
00bab910 SS	228	/* new piece must not exceed next page boundary */
1da177e4	229	length = min(remaining,
00bab910	230	(PAGE_SIZE - ((unsigned long)addr &
1da177e4	231	(PAGE_SIZE - 1))));
00bab910 SS	232	sbale->addr = addr;
00bab910 SS	233	sbale->length = length;
1da177e4	234	}
00bab910	235	return 0;
1da177e4 LT	236	}
1da177e4 LT	237
1da177e4 LT	238	/**
	239	* zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list
	240	* @fsf_req: request to be processed
	241	* @sbtype: SBALE flags
	242	* @sg: scatter-gather list
1da177e4	243	* @max_sbals: upper bound for number of SBALs to be used
00bab910	244	* Returns: number of bytes, or error (negativ)
1da177e4	245	*/
34c2b712	246	int zfcp_qdio_sbals_from_sg(struct zfcp_qdio qdio, struct zfcp_qdio_req q_req,
42428f74 SS	247	unsigned long sbtype, struct scatterlist *sg,
42428f74 SS	248	int max_sbals)
1da177e4	249	{
44cc76f2	250	struct qdio_buffer_element *sbale;
00bab910	251	int retval, bytes = 0;
1da177e4 LT	252
1da177e4 LT	253	/* figure out last allowed SBAL */
564e1c86	254	zfcp_qdio_sbal_limit(qdio, q_req, max_sbals);
1da177e4	255
00bab910	256	/* set storage-block type for this request */
564e1c86	257	sbale = zfcp_qdio_sbale_req(qdio, q_req);
1da177e4 LT	258	sbale->flags \|= sbtype;
1da177e4 LT	259
00bab910	260	for (; sg; sg = sg_next(sg)) {
564e1c86	261	retval = zfcp_qdio_fill_sbals(qdio, q_req, sbtype,
42428f74	262	sg_virt(sg), sg->length);
00bab910 SS	263	if (retval < 0)
	264	return retval;
	265	bytes += sg->length;
1da177e4	266	}
00bab910	267
1da177e4	268	/* assume that no other SBALEs are to follow in the same SBAL */
564e1c86	269	sbale = zfcp_qdio_sbale_curr(qdio, q_req);
1da177e4	270	sbale->flags \|= SBAL_FLAGS_LAST_ENTRY;
00bab910	271
1da177e4 LT	272	return bytes;
	273	}
	274
1da177e4	275	/**
00bab910	276	* zfcp_qdio_send - set PCI flag in first SBALE and send req to QDIO
564e1c86	277	* @qdio: pointer to struct zfcp_qdio
34c2b712	278	* @q_req: pointer to struct zfcp_qdio_req
00bab910	279	* Returns: 0 on success, error otherwise
1da177e4	280	*/
34c2b712	281	int zfcp_qdio_send(struct zfcp_qdio qdio, struct zfcp_qdio_req q_req)
1da177e4	282	{
564e1c86	283	struct zfcp_qdio_queue *req_q = &qdio->req_q;
42428f74 SS	284	int first = q_req->sbal_first;
42428f74 SS	285	int count = q_req->sbal_number;
21ddaa53 CS	286	int retval;
21ddaa53 CS	287	unsigned int qdio_flags = QDIO_FLAG_SYNC_OUTPUT;
00bab910	288
564e1c86	289	zfcp_qdio_account(qdio);
94506fd1	290
564e1c86 SS	291	retval = do_QDIO(qdio->adapter->ccw_device, qdio_flags, 0, first,
564e1c86 SS	292	count);
00bab910 SS	293	if (unlikely(retval)) {
	294	zfcp_qdio_zero_sbals(req_q->sbal, first, count);
	295	return retval;
	296	}
	297
	298	/* account for transferred buffers */
	299	atomic_sub(count, &req_q->count);
	300	req_q->first += count;
	301	req_q->first %= QDIO_MAX_BUFFERS_PER_Q;
00bab910	302	return 0;
1da177e4 LT	303	}
1da177e4 LT	304
564e1c86 SS	305
	306	static void zfcp_qdio_setup_init_data(struct qdio_initialize *id,
	307	struct zfcp_qdio *qdio)
	308	{
	309
	310	id->cdev = qdio->adapter->ccw_device;
	311	id->q_format = QDIO_ZFCP_QFMT;
	312	memcpy(id->adapter_name, dev_name(&id->cdev->dev), 8);
	313	ASCEBC(id->adapter_name, 8);
	314	id->qib_param_field_format = 0;
	315	id->qib_param_field = NULL;
	316	id->input_slib_elements = NULL;
	317	id->output_slib_elements = NULL;
	318	id->no_input_qs = 1;
	319	id->no_output_qs = 1;
	320	id->input_handler = zfcp_qdio_int_resp;
	321	id->output_handler = zfcp_qdio_int_req;
	322	id->int_parm = (unsigned long) qdio;
564e1c86 SS	323	id->input_sbal_addr_array = (void **) (qdio->resp_q.sbal);
	324	id->output_sbal_addr_array = (void **) (qdio->req_q.sbal);
	325
	326	}
00bab910 SS	327	/**
	328	* zfcp_qdio_allocate - allocate queue memory and initialize QDIO data
	329	* @adapter: pointer to struct zfcp_adapter
	330	* Returns: -ENOMEM on memory allocation error or return value from
	331	* qdio_allocate
	332	*/
d5a282a1	333	static int zfcp_qdio_allocate(struct zfcp_qdio *qdio)
00bab910	334	{
564e1c86	335	struct qdio_initialize init_data;
00bab910	336
564e1c86 SS	337	if (zfcp_qdio_buffers_enqueue(qdio->req_q.sbal) \|\|
564e1c86 SS	338	zfcp_qdio_buffers_enqueue(qdio->resp_q.sbal))
00bab910 SS	339	return -ENOMEM;
00bab910 SS	340
564e1c86 SS	341	zfcp_qdio_setup_init_data(&init_data, qdio);
	342
	343	return qdio_allocate(&init_data);
00bab910 SS	344	}
	345
	346	/**
	347	* zfcp_close_qdio - close qdio queues for an adapter
564e1c86	348	* @qdio: pointer to structure zfcp_qdio
1da177e4	349	*/
564e1c86	350	void zfcp_qdio_close(struct zfcp_qdio *qdio)
1da177e4	351	{
00bab910 SS	352	struct zfcp_qdio_queue *req_q;
	353	int first, count;
	354
564e1c86	355	if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
00bab910 SS	356	return;
	357
	358	/* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */
564e1c86 SS	359	req_q = &qdio->req_q;
	360	spin_lock_bh(&qdio->req_q_lock);
	361	atomic_clear_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &qdio->adapter->status);
	362	spin_unlock_bh(&qdio->req_q_lock);
00bab910	363
564e1c86 SS	364	qdio_shutdown(qdio->adapter->ccw_device,
564e1c86 SS	365	QDIO_FLAG_CLEANUP_USING_CLEAR);
00bab910 SS	366
	367	/* cleanup used outbound sbals */
	368	count = atomic_read(&req_q->count);
	369	if (count < QDIO_MAX_BUFFERS_PER_Q) {
	370	first = (req_q->first + count) % QDIO_MAX_BUFFERS_PER_Q;
	371	count = QDIO_MAX_BUFFERS_PER_Q - count;
	372	zfcp_qdio_zero_sbals(req_q->sbal, first, count);
1da177e4	373	}
00bab910 SS	374	req_q->first = 0;
00bab910 SS	375	atomic_set(&req_q->count, 0);
564e1c86 SS	376	qdio->resp_q.first = 0;
564e1c86 SS	377	atomic_set(&qdio->resp_q.count, 0);
1da177e4 LT	378	}
1da177e4 LT	379
00bab910 SS	380	/**
00bab910 SS	381	* zfcp_qdio_open - prepare and initialize response queue
564e1c86	382	* @qdio: pointer to struct zfcp_qdio
00bab910 SS	383	* Returns: 0 on success, otherwise -EIO
00bab910 SS	384	*/
564e1c86	385	int zfcp_qdio_open(struct zfcp_qdio *qdio)
00bab910	386	{
44cc76f2	387	struct qdio_buffer_element *sbale;
564e1c86 SS	388	struct qdio_initialize init_data;
564e1c86 SS	389	struct ccw_device *cdev = qdio->adapter->ccw_device;
00bab910 SS	390	int cc;
00bab910 SS	391
564e1c86	392	if (atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)
00bab910 SS	393	return -EIO;
00bab910 SS	394
564e1c86 SS	395	zfcp_qdio_setup_init_data(&init_data, qdio);
	396
	397	if (qdio_establish(&init_data))
ff3b24fa	398	goto failed_establish;
00bab910	399
564e1c86	400	if (qdio_activate(cdev))
00bab910	401	goto failed_qdio;
00bab910 SS	402
00bab910 SS	403	for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) {
564e1c86	404	sbale = &(qdio->resp_q.sbal[cc]->element[0]);
00bab910 SS	405	sbale->length = 0;
	406	sbale->flags = SBAL_FLAGS_LAST_ENTRY;
	407	sbale->addr = NULL;
	408	}
	409
564e1c86	410	if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, 0,
ff3b24fa	411	QDIO_MAX_BUFFERS_PER_Q))
00bab910	412	goto failed_qdio;
00bab910 SS	413
00bab910 SS	414	/* set index of first avalable SBALS / number of available SBALS */
564e1c86 SS	415	qdio->req_q.first = 0;
564e1c86 SS	416	atomic_set(&qdio->req_q.count, QDIO_MAX_BUFFERS_PER_Q);
00bab910 SS	417
	418	return 0;
	419
	420	failed_qdio:
564e1c86	421	qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR);
ff3b24fa	422	failed_establish:
564e1c86	423	dev_err(&cdev->dev,
ff3b24fa	424	"Setting up the QDIO connection to the FCP adapter failed\n");
00bab910 SS	425	return -EIO;
00bab910 SS	426	}
d5a282a1 SS	427
	428	void zfcp_qdio_destroy(struct zfcp_qdio *qdio)
	429	{
	430	struct qdio_buffer sbal_req, sbal_resp;
	431	int p;
	432
	433	if (!qdio)
	434	return;
	435
	436	if (qdio->adapter->ccw_device)
	437	qdio_free(qdio->adapter->ccw_device);
	438
	439	sbal_req = qdio->req_q.sbal;
	440	sbal_resp = qdio->resp_q.sbal;
	441
	442	for (p = 0; p < QDIO_MAX_BUFFERS_PER_Q; p += QBUFF_PER_PAGE) {
	443	free_page((unsigned long) sbal_req[p]);
	444	free_page((unsigned long) sbal_resp[p]);
	445	}
	446
	447	kfree(qdio);
	448	}
	449
	450	int zfcp_qdio_setup(struct zfcp_adapter *adapter)
	451	{
	452	struct zfcp_qdio *qdio;
	453
	454	qdio = kzalloc(sizeof(struct zfcp_qdio), GFP_KERNEL);
	455	if (!qdio)
	456	return -ENOMEM;
	457
	458	qdio->adapter = adapter;
	459
	460	if (zfcp_qdio_allocate(qdio)) {
	461	zfcp_qdio_destroy(qdio);
	462	return -ENOMEM;
	463	}
	464
	465	spin_lock_init(&qdio->req_q_lock);
	466	spin_lock_init(&qdio->stat_lock);
	467
	468	adapter->qdio = qdio;
	469	return 0;
	470	}
	471