declarations for common work and completion queue.

Signed-off-by: Bob Pearson <rpear...@systemfabricworks.com>

---
 drivers/infiniband/hw/rxe/rxe_queue.h |  174 ++++++++++++++++++++++++++++++++++
 1 file changed, 174 insertions(+)

Index: infiniband/drivers/infiniband/hw/rxe/rxe_queue.h
===================================================================
--- /dev/null
+++ infiniband/drivers/infiniband/hw/rxe/rxe_queue.h
@@ -0,0 +1,174 @@
+/*
+ * Copyright (c) 2009-2011 Mellanox Technologies Ltd. All rights reserved.
+ * Copyright (c) 2009-2011 System Fabric Works, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *     - Redistributions of source code must retain the above
+ *       copyright notice, this list of conditions and the following
+ *       disclaimer.
+ *
+ *     - Redistributions in binary form must reproduce the above
+ *       copyright notice, this list of conditions and the following
+ *       disclaimer in the documentation and/or other materials
+ *       provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef RXE_QUEUE_H
+#define RXE_QUEUE_H
+
+/* implements a simple circular buffer that can optionally be
+   shared between user space and the kernel and can be resized
+
+   the requested element size is rounded up to a power of 2
+   and the number of elements in the buffer is also rounded
+   up to a power of 2. Since the queue is empty when the
+   producer and consumer indices match the maximum capacity
+   of the queue is one less than the number of element slots */
+
+/* this data structure is shared between user space and kernel
+   space for those cases where the queue is shared. It contains
+   the producer and consumer indices. Is also contains a copy
+   of the queue size parameters for user space to use but the
+   kernel must use the parameters in the rxe_queue struct
+   this MUST MATCH the corresponding librxe struct
+   for performance reasons arrange to have producer and consumer
+   pointers in separate cache lines
+   the kernel should always mask the indices to avoid accessing
+   memory outside of the data area */
+struct rxe_queue_buf {
+       __u32                   log2_elem_size;
+       __u32                   index_mask;
+       __u32                   pad_1[30];
+       __u32                   producer_index;
+       __u32                   pad_2[31];
+       __u32                   consumer_index;
+       __u32                   pad_3[31];
+       __u8                    data[0];
+};
+
+struct rxe_queue {
+       struct rxe_dev          *rxe;
+       struct rxe_queue_buf    *buf;
+       struct rxe_mmap_info    *ip;
+       size_t                  buf_size;
+       size_t                  elem_size;
+       unsigned int            log2_elem_size;
+       unsigned int            index_mask;
+};
+
+int do_mmap_info(struct rxe_dev *rxe,
+                struct ib_udata *udata,
+                int offset,
+                struct ib_ucontext *context,
+                struct rxe_queue_buf *buf,
+                size_t buf_size,
+                struct rxe_mmap_info **ip_p);
+
+struct rxe_queue *rxe_queue_init(struct rxe_dev *rxe,
+                                unsigned int *num_elem,
+                                unsigned int elem_size);
+
+int rxe_queue_resize(struct rxe_queue *q,
+                    unsigned int *num_elem_p,
+                    unsigned int elem_size,
+                    struct ib_ucontext *context,
+                    struct ib_udata *udata,
+                    spinlock_t *producer_lock,
+                    spinlock_t *consumer_lock);
+
+void rxe_queue_cleanup(struct rxe_queue *queue);
+
+static inline int next_index(struct rxe_queue *q, int index)
+{
+       return (index + 1) & q->buf->index_mask;
+}
+
+static inline int queue_empty(struct rxe_queue *q)
+{
+       return ((q->buf->producer_index - q->buf->consumer_index)
+                       & q->index_mask) == 0;
+}
+
+static inline int queue_full(struct rxe_queue *q)
+{
+       return ((q->buf->producer_index + 1 - q->buf->consumer_index)
+                       & q->index_mask) == 0;
+}
+
+static inline void advance_producer(struct rxe_queue *q)
+{
+       q->buf->producer_index = (q->buf->producer_index + 1)
+                       & q->index_mask;
+}
+
+static inline void advance_consumer(struct rxe_queue *q)
+{
+       q->buf->consumer_index = (q->buf->consumer_index + 1)
+                       & q->index_mask;
+}
+
+static inline void *producer_addr(struct rxe_queue *q)
+{
+       return q->buf->data + ((q->buf->producer_index & q->index_mask)
+                               << q->log2_elem_size);
+}
+
+static inline void *consumer_addr(struct rxe_queue *q)
+{
+       return q->buf->data + ((q->buf->consumer_index & q->index_mask)
+                               << q->log2_elem_size);
+}
+
+static inline unsigned int producer_index(struct rxe_queue *q)
+{
+       return q->buf->producer_index;
+}
+
+static inline unsigned int consumer_index(struct rxe_queue *q)
+{
+       return q->buf->consumer_index;
+}
+
+static inline void *addr_from_index(struct rxe_queue *q, unsigned int index)
+{
+       return q->buf->data + ((index & q->index_mask)
+                               << q->buf->log2_elem_size);
+}
+
+static inline unsigned int index_from_addr(const struct rxe_queue *q,
+                                          const void *addr)
+{
+       return (((u8 *)addr - q->buf->data) >> q->log2_elem_size)
+               & q->index_mask;
+}
+
+static inline unsigned int queue_count(const struct rxe_queue *q)
+{
+       return (q->buf->producer_index - q->buf->consumer_index)
+               & q->index_mask;
+}
+
+static inline void *queue_head(struct rxe_queue *q)
+{
+       return queue_empty(q) ? NULL : consumer_addr(q);
+}
+
+#endif /* RXE_QUEUE_H */

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