1 files changed, 505 insertions, 0 deletions

diff --git a/drivers/s390/scsi/zfcp_qdio.c b/drivers/s390/scsi/zfcp_qdio.c
new file mode 100644
index 000000000..4ab02e8d3
--- /dev/null
+++ b/drivers/s390/scsi/zfcp_qdio.c
@@ -0,0 +1,505 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * zfcp device driver
+ *
+ * Setup and helper functions to access QDIO.
+ *
+ * Copyright IBM Corp. 2002, 2010
+ */
+
+#define KMSG_COMPONENT "zfcp"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/slab.h>
+#include <linux/module.h>
+#include "zfcp_ext.h"
+#include "zfcp_qdio.h"
+
+static bool enable_multibuffer = true;
+module_param_named(datarouter, enable_multibuffer, bool, 0400);
+MODULE_PARM_DESC(datarouter, "Enable hardware data router support (default on)");
+
+static void zfcp_qdio_handler_error(struct zfcp_qdio *qdio, char *id,
+				    unsigned int qdio_err)
+{
+	struct zfcp_adapter *adapter = qdio->adapter;
+
+	dev_warn(&adapter->ccw_device->dev, "A QDIO problem occurred\n");
+
+	if (qdio_err & QDIO_ERROR_SLSB_STATE) {
+		zfcp_qdio_siosl(adapter);
+		zfcp_erp_adapter_shutdown(adapter, 0, id);
+		return;
+	}
+	zfcp_erp_adapter_reopen(adapter,
+				ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED |
+				ZFCP_STATUS_COMMON_ERP_FAILED, id);
+}
+
+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 used;
+
+	now = get_tod_clock_monotonic();
+	span = (now - qdio->req_q_time) >> 12;
+	used = QDIO_MAX_BUFFERS_PER_Q - atomic_read(&qdio->req_q_free);
+	qdio->req_q_util += used * span;
+	qdio->req_q_time = now;
+}
+
+static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err,
+			      int queue_no, int idx, int count,
+			      unsigned long parm)
+{
+	struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;
+
+	if (unlikely(qdio_err)) {
+		zfcp_qdio_handler_error(qdio, "qdireq1", qdio_err);
+		return;
+	}
+
+	/* cleanup all SBALs being program-owned now */
+	zfcp_qdio_zero_sbals(qdio->req_q, idx, count);
+
+	spin_lock_irq(&qdio->stat_lock);
+	zfcp_qdio_account(qdio);
+	spin_unlock_irq(&qdio->stat_lock);
+	atomic_add(count, &qdio->req_q_free);
+	wake_up(&qdio->req_q_wq);
+}
+
+static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err,
+			       int queue_no, int idx, int count,
+			       unsigned long parm)
+{
+	struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;
+	struct zfcp_adapter *adapter = qdio->adapter;
+	int sbal_no, sbal_idx;
+
+	if (unlikely(qdio_err)) {
+		if (zfcp_adapter_multi_buffer_active(adapter)) {
+			void *pl[ZFCP_QDIO_MAX_SBALS_PER_REQ + 1];
+			struct qdio_buffer_element *sbale;
+			u64 req_id;
+			u8 scount;
+
+			memset(pl, 0,
+			       ZFCP_QDIO_MAX_SBALS_PER_REQ * sizeof(void *));
+			sbale = qdio->res_q[idx]->element;
+			req_id = (u64) sbale->addr;
+			scount = min(sbale->scount + 1,
+				     ZFCP_QDIO_MAX_SBALS_PER_REQ + 1);
+				     /* incl. signaling SBAL */
+
+			for (sbal_no = 0; sbal_no < scount; sbal_no++) {
+				sbal_idx = (idx + sbal_no) %
+					QDIO_MAX_BUFFERS_PER_Q;
+				pl[sbal_no] = qdio->res_q[sbal_idx];
+			}
+			zfcp_dbf_hba_def_err(adapter, req_id, scount, pl);
+		}
+		zfcp_qdio_handler_error(qdio, "qdires1", qdio_err);
+		return;
+	}
+
+	/*
+	 * go through all SBALs from input queue currently
+	 * returned by QDIO layer
+	 */
+	for (sbal_no = 0; sbal_no < count; sbal_no++) {
+		sbal_idx = (idx + sbal_no) % QDIO_MAX_BUFFERS_PER_Q;
+		/* go through all SBALEs of SBAL */
+		zfcp_fsf_reqid_check(qdio, sbal_idx);
+	}
+
+	/*
+	 * put SBALs back to response queue
+	 */
+	if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, idx, count))
+		zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdires2");
+}
+
+static struct qdio_buffer_element *
+zfcp_qdio_sbal_chain(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
+{
+	struct qdio_buffer_element *sbale;
+
+	/* set last entry flag in current SBALE of current SBAL */
+	sbale = zfcp_qdio_sbale_curr(qdio, q_req);
+	sbale->eflags |= SBAL_EFLAGS_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->sflags |= SBAL_SFLAGS0_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++;
+	BUG_ON(q_req->sbal_number > ZFCP_QDIO_MAX_SBALS_PER_REQ);
+
+	/* 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->sflags |= q_req->sbtype;
+
+	return sbale;
+}
+
+static struct qdio_buffer_element *
+zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
+{
+	if (q_req->sbale_curr == qdio->max_sbale_per_sbal - 1)
+		return zfcp_qdio_sbal_chain(qdio, q_req);
+	q_req->sbale_curr++;
+	return zfcp_qdio_sbale_curr(qdio, q_req);
+}
+
+/**
+ * zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list
+ * @qdio: pointer to struct zfcp_qdio
+ * @q_req: pointer to struct zfcp_qdio_req
+ * @sg: scatter-gather list
+ * @max_sbals: upper bound for number of SBALs to be used
+ * Returns: zero or -EINVAL on error
+ */
+int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req,
+			    struct scatterlist *sg)
+{
+	struct qdio_buffer_element *sbale;
+
+	/* set storage-block type for this request */
+	sbale = zfcp_qdio_sbale_req(qdio, q_req);
+	sbale->sflags |= q_req->sbtype;
+
+	for (; sg; sg = sg_next(sg)) {
+		sbale = zfcp_qdio_sbale_next(qdio, q_req);
+		if (!sbale) {
+			atomic_inc(&qdio->req_q_full);
+			zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first,
+					     q_req->sbal_number);
+			return -EINVAL;
+		}
+		sbale->addr = sg_virt(sg);
+		sbale->length = sg->length;
+	}
+	return 0;
+}
+
+static int zfcp_qdio_sbal_check(struct zfcp_qdio *qdio)
+{
+	if (atomic_read(&qdio->req_q_free) ||
+	    !(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
+		return 1;
+	return 0;
+}
+
+/**
+ * zfcp_qdio_sbal_get - get free sbal in request queue, wait if necessary
+ * @qdio: pointer to struct zfcp_qdio
+ *
+ * The req_q_lock must be held by the caller of this function, and
+ * this function may only be called from process context; it will
+ * sleep when waiting for a free sbal.
+ *
+ * Returns: 0 on success, -EIO if there is no free sbal after waiting.
+ */
+int zfcp_qdio_sbal_get(struct zfcp_qdio *qdio)
+{
+	long ret;
+
+	ret = wait_event_interruptible_lock_irq_timeout(qdio->req_q_wq,
+		       zfcp_qdio_sbal_check(qdio), qdio->req_q_lock, 5 * HZ);
+
+	if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
+		return -EIO;
+
+	if (ret > 0)
+		return 0;
+
+	if (!ret) {
+		atomic_inc(&qdio->req_q_full);
+		/* assume hanging outbound queue, try queue recovery */
+		zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdsbg_1");
+	}
+
+	return -EIO;
+}
+
+/**
+ * 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)
+{
+	int retval;
+	u8 sbal_number = q_req->sbal_number;
+
+	spin_lock(&qdio->stat_lock);
+	zfcp_qdio_account(qdio);
+	spin_unlock(&qdio->stat_lock);
+
+	retval = do_QDIO(qdio->adapter->ccw_device, QDIO_FLAG_SYNC_OUTPUT, 0,
+			 q_req->sbal_first, sbal_number);
+
+	if (unlikely(retval)) {
+		zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first,
+				     sbal_number);
+		return retval;
+	}
+
+	/* account for transferred buffers */
+	atomic_sub(sbal_number, &qdio->req_q_free);
+	qdio->req_q_idx += sbal_number;
+	qdio->req_q_idx %= QDIO_MAX_BUFFERS_PER_Q;
+
+	return 0;
+}
+
+
+static void zfcp_qdio_setup_init_data(struct qdio_initialize *id,
+				      struct zfcp_qdio *qdio)
+{
+	memset(id, 0, sizeof(*id));
+	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_rflags = QIB_RFLAGS_ENABLE_DATA_DIV;
+	if (enable_multibuffer)
+		id->qdr_ac |= QDR_AC_MULTI_BUFFER_ENABLE;
+	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->res_q);
+	id->output_sbal_addr_array = (void **) (qdio->req_q);
+	id->scan_threshold =
+		QDIO_MAX_BUFFERS_PER_Q - ZFCP_QDIO_MAX_SBALS_PER_REQ * 2;
+}
+
+/**
+ * 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;
+	int ret;
+
+	ret = qdio_alloc_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q);
+	if (ret)
+		return -ENOMEM;
+
+	ret = qdio_alloc_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q);
+	if (ret)
+		goto free_req_q;
+
+	zfcp_qdio_setup_init_data(&init_data, qdio);
+	init_waitqueue_head(&qdio->req_q_wq);
+
+	ret = qdio_allocate(&init_data);
+	if (ret)
+		goto free_res_q;
+
+	return 0;
+
+free_res_q:
+	qdio_free_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q);
+free_req_q:
+	qdio_free_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q);
+	return ret;
+}
+
+/**
+ * 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_adapter *adapter = qdio->adapter;
+	int idx, count;
+
+	if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
+		return;
+
+	/* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */
+	spin_lock_irq(&qdio->req_q_lock);
+	atomic_andnot(ZFCP_STATUS_ADAPTER_QDIOUP, &adapter->status);
+	spin_unlock_irq(&qdio->req_q_lock);
+
+	wake_up(&qdio->req_q_wq);
+
+	qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR);
+
+	/* cleanup used outbound sbals */
+	count = atomic_read(&qdio->req_q_free);
+	if (count < QDIO_MAX_BUFFERS_PER_Q) {
+		idx = (qdio->req_q_idx + count) % QDIO_MAX_BUFFERS_PER_Q;
+		count = QDIO_MAX_BUFFERS_PER_Q - count;
+		zfcp_qdio_zero_sbals(qdio->req_q, idx, count);
+	}
+	qdio->req_q_idx = 0;
+	atomic_set(&qdio->req_q_free, 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 zfcp_adapter *adapter = qdio->adapter;
+	struct ccw_device *cdev = adapter->ccw_device;
+	struct qdio_ssqd_desc ssqd;
+	int cc;
+
+	if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)
+		return -EIO;
+
+	atomic_andnot(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED,
+			  &qdio->adapter->status);
+
+	zfcp_qdio_setup_init_data(&init_data, qdio);
+
+	if (qdio_establish(&init_data))
+		goto failed_establish;
+
+	if (qdio_get_ssqd_desc(init_data.cdev, &ssqd))
+		goto failed_qdio;
+
+	if (ssqd.qdioac2 & CHSC_AC2_DATA_DIV_ENABLED)
+		atomic_or(ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED,
+				&qdio->adapter->status);
+
+	if (ssqd.qdioac2 & CHSC_AC2_MULTI_BUFFER_ENABLED) {
+		atomic_or(ZFCP_STATUS_ADAPTER_MB_ACT, &adapter->status);
+		qdio->max_sbale_per_sbal = QDIO_MAX_ELEMENTS_PER_BUFFER;
+	} else {
+		atomic_andnot(ZFCP_STATUS_ADAPTER_MB_ACT, &adapter->status);
+		qdio->max_sbale_per_sbal = QDIO_MAX_ELEMENTS_PER_BUFFER - 1;
+	}
+
+	qdio->max_sbale_per_req =
+		ZFCP_QDIO_MAX_SBALS_PER_REQ * qdio->max_sbale_per_sbal
+		- 2;
+	if (qdio_activate(cdev))
+		goto failed_qdio;
+
+	for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) {
+		sbale = &(qdio->res_q[cc]->element[0]);
+		sbale->length = 0;
+		sbale->eflags = SBAL_EFLAGS_LAST_ENTRY;
+		sbale->sflags = 0;
+		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 available SBALS / number of available SBALS */
+	qdio->req_q_idx = 0;
+	atomic_set(&qdio->req_q_free, QDIO_MAX_BUFFERS_PER_Q);
+	atomic_or(ZFCP_STATUS_ADAPTER_QDIOUP, &qdio->adapter->status);
+
+	if (adapter->scsi_host) {
+		adapter->scsi_host->sg_tablesize = qdio->max_sbale_per_req;
+		adapter->scsi_host->max_sectors = qdio->max_sbale_per_req * 8;
+	}
+
+	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)
+{
+	if (!qdio)
+		return;
+
+	if (qdio->adapter->ccw_device)
+		qdio_free(qdio->adapter->ccw_device);
+
+	qdio_free_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q);
+	qdio_free_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q);
+	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)) {
+		kfree(qdio);
+		return -ENOMEM;
+	}
+
+	spin_lock_init(&qdio->req_q_lock);
+	spin_lock_init(&qdio->stat_lock);
+
+	adapter->qdio = qdio;
+	return 0;
+}
+
+/**
+ * zfcp_qdio_siosl - Trigger logging in FCP channel
+ * @adapter: The zfcp_adapter where to trigger logging
+ *
+ * Call the cio siosl function to trigger hardware logging.  This
+ * wrapper function sets a flag to ensure hardware logging is only
+ * triggered once before going through qdio shutdown.
+ *
+ * The triggers are always run from qdio tasklet context, so no
+ * additional synchronization is necessary.
+ */
+void zfcp_qdio_siosl(struct zfcp_adapter *adapter)
+{
+	int rc;
+
+	if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_SIOSL_ISSUED)
+		return;
+
+	rc = ccw_device_siosl(adapter->ccw_device);
+	if (!rc)
+		atomic_or(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED,
+				&adapter->status);
+}