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path: root/drivers/s390/scsi/zfcp_qdio.h
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Diffstat (limited to 'drivers/s390/scsi/zfcp_qdio.h')
-rw-r--r--drivers/s390/scsi/zfcp_qdio.h95
1 files changed, 58 insertions, 37 deletions
diff --git a/drivers/s390/scsi/zfcp_qdio.h b/drivers/s390/scsi/zfcp_qdio.h
index 138fba577b4..2297d8d3e94 100644
--- a/drivers/s390/scsi/zfcp_qdio.h
+++ b/drivers/s390/scsi/zfcp_qdio.h
@@ -19,22 +19,20 @@
/* index of last SBALE (with respect to DMQ bug workaround) */
#define ZFCP_QDIO_LAST_SBALE_PER_SBAL (ZFCP_QDIO_MAX_SBALES_PER_SBAL - 1)
-/**
- * struct zfcp_qdio_queue - qdio queue buffer, zfcp index and free count
- * @sbal: qdio buffers
- * @first: index of next free buffer in queue
- * @count: number of free buffers in queue
- */
-struct zfcp_qdio_queue {
- struct qdio_buffer *sbal[QDIO_MAX_BUFFERS_PER_Q];
- u8 first;
- atomic_t count;
-};
+/* Max SBALS for chaining */
+#define ZFCP_QDIO_MAX_SBALS_PER_REQ 36
+
+/* max. number of (data buffer) SBALEs in largest SBAL chain
+ * request ID + QTCB in SBALE 0 + 1 of first SBAL in chain */
+#define ZFCP_QDIO_MAX_SBALES_PER_REQ \
+ (ZFCP_QDIO_MAX_SBALS_PER_REQ * ZFCP_QDIO_MAX_SBALES_PER_SBAL - 2)
/**
* struct zfcp_qdio - basic qdio data structure
- * @resp_q: response queue
+ * @res_q: response queue
* @req_q: request queue
+ * @req_q_idx: index of next free buffer
+ * @req_q_free: number of free buffers in queue
* @stat_lock: lock to protect req_q_util and req_q_time
* @req_q_lock: lock to serialize access to request queue
* @req_q_time: time of last fill level change
@@ -44,8 +42,10 @@ struct zfcp_qdio_queue {
* @adapter: adapter used in conjunction with this qdio structure
*/
struct zfcp_qdio {
- struct zfcp_qdio_queue resp_q;
- struct zfcp_qdio_queue req_q;
+ struct qdio_buffer *res_q[QDIO_MAX_BUFFERS_PER_Q];
+ struct qdio_buffer *req_q[QDIO_MAX_BUFFERS_PER_Q];
+ u8 req_q_idx;
+ atomic_t req_q_free;
spinlock_t stat_lock;
spinlock_t req_q_lock;
unsigned long long req_q_time;
@@ -65,7 +65,6 @@ struct zfcp_qdio {
* @sbale_curr: current sbale at creation of this request
* @sbal_response: sbal used in interrupt
* @qdio_outb_usage: usage of outbound queue
- * @qdio_inb_usage: usage of inbound queue
*/
struct zfcp_qdio_req {
u32 sbtype;
@@ -76,22 +75,9 @@ struct zfcp_qdio_req {
u8 sbale_curr;
u8 sbal_response;
u16 qdio_outb_usage;
- u16 qdio_inb_usage;
};
/**
- * zfcp_qdio_sbale - return pointer to sbale in qdio queue
- * @q: queue where to find sbal
- * @sbal_idx: sbal index in queue
- * @sbale_idx: sbale index in sbal
- */
-static inline 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_sbale_req - return pointer to sbale on req_q for a request
* @qdio: pointer to struct zfcp_qdio
* @q_rec: pointer to struct zfcp_qdio_req
@@ -100,7 +86,7 @@ zfcp_qdio_sbale(struct zfcp_qdio_queue *q, int sbal_idx, int sbale_idx)
static inline struct qdio_buffer_element *
zfcp_qdio_sbale_req(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
{
- return zfcp_qdio_sbale(&qdio->req_q, q_req->sbal_last, 0);
+ return &qdio->req_q[q_req->sbal_last]->element[0];
}
/**
@@ -112,8 +98,7 @@ zfcp_qdio_sbale_req(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
static inline struct qdio_buffer_element *
zfcp_qdio_sbale_curr(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
{
- return zfcp_qdio_sbale(&qdio->req_q, q_req->sbal_last,
- q_req->sbale_curr);
+ return &qdio->req_q[q_req->sbal_last]->element[q_req->sbale_curr];
}
/**
@@ -134,21 +119,25 @@ void zfcp_qdio_req_init(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req,
unsigned long req_id, u32 sbtype, void *data, u32 len)
{
struct qdio_buffer_element *sbale;
+ int count = min(atomic_read(&qdio->req_q_free),
+ ZFCP_QDIO_MAX_SBALS_PER_REQ);
- q_req->sbal_first = q_req->sbal_last = qdio->req_q.first;
+ q_req->sbal_first = q_req->sbal_last = qdio->req_q_idx;
q_req->sbal_number = 1;
q_req->sbtype = sbtype;
+ q_req->sbale_curr = 1;
+ q_req->sbal_limit = (q_req->sbal_first + count - 1)
+ % QDIO_MAX_BUFFERS_PER_Q;
sbale = zfcp_qdio_sbale_req(qdio, q_req);
sbale->addr = (void *) req_id;
- sbale->flags |= SBAL_FLAGS0_COMMAND;
- sbale->flags |= sbtype;
+ sbale->flags = SBAL_FLAGS0_COMMAND | sbtype;
- q_req->sbale_curr = 1;
+ if (unlikely(!data))
+ return;
sbale++;
sbale->addr = data;
- if (likely(data))
- sbale->length = len;
+ sbale->length = len;
}
/**
@@ -210,4 +199,36 @@ void zfcp_qdio_skip_to_last_sbale(struct zfcp_qdio_req *q_req)
q_req->sbale_curr = ZFCP_QDIO_LAST_SBALE_PER_SBAL;
}
+/**
+ * zfcp_qdio_sbal_limit - set the sbal limit for a request in q_req
+ * @qdio: pointer to struct zfcp_qdio
+ * @q_req: The current zfcp_qdio_req
+ * @max_sbals: maximum number of SBALs allowed
+ */
+static inline
+void zfcp_qdio_sbal_limit(struct zfcp_qdio *qdio,
+ struct zfcp_qdio_req *q_req, int max_sbals)
+{
+ int count = min(atomic_read(&qdio->req_q_free), max_sbals);
+
+ q_req->sbal_limit = (q_req->sbal_first + count - 1) %
+ QDIO_MAX_BUFFERS_PER_Q;
+}
+
+/**
+ * zfcp_qdio_set_data_div - set data division count
+ * @qdio: pointer to struct zfcp_qdio
+ * @q_req: The current zfcp_qdio_req
+ * @count: The data division count
+ */
+static inline
+void zfcp_qdio_set_data_div(struct zfcp_qdio *qdio,
+ struct zfcp_qdio_req *q_req, u32 count)
+{
+ struct qdio_buffer_element *sbale;
+
+ sbale = &qdio->req_q[q_req->sbal_first]->element[0];
+ sbale->length = count;
+}
+
#endif /* ZFCP_QDIO_H */