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-rw-r--r--net/rds/iw_ring.c169
1 files changed, 0 insertions, 169 deletions
diff --git a/net/rds/iw_ring.c b/net/rds/iw_ring.c
deleted file mode 100644
index da8e3b63f663..000000000000
--- a/net/rds/iw_ring.c
+++ /dev/null
@@ -1,169 +0,0 @@
-/*
- * Copyright (c) 2006 Oracle. 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.
- *
- */
-#include <linux/kernel.h>
-
-#include "rds.h"
-#include "iw.h"
-
-/*
- * Locking for IB rings.
- * We assume that allocation is always protected by a mutex
- * in the caller (this is a valid assumption for the current
- * implementation).
- *
- * Freeing always happens in an interrupt, and hence only
- * races with allocations, but not with other free()s.
- *
- * The interaction between allocation and freeing is that
- * the alloc code has to determine the number of free entries.
- * To this end, we maintain two counters; an allocation counter
- * and a free counter. Both are allowed to run freely, and wrap
- * around.
- * The number of used entries is always (alloc_ctr - free_ctr) % NR.
- *
- * The current implementation makes free_ctr atomic. When the
- * caller finds an allocation fails, it should set an "alloc fail"
- * bit and retry the allocation. The "alloc fail" bit essentially tells
- * the CQ completion handlers to wake it up after freeing some
- * more entries.
- */
-
-/*
- * This only happens on shutdown.
- */
-DECLARE_WAIT_QUEUE_HEAD(rds_iw_ring_empty_wait);
-
-void rds_iw_ring_init(struct rds_iw_work_ring *ring, u32 nr)
-{
- memset(ring, 0, sizeof(*ring));
- ring->w_nr = nr;
- rdsdebug("ring %p nr %u\n", ring, ring->w_nr);
-}
-
-static inline u32 __rds_iw_ring_used(struct rds_iw_work_ring *ring)
-{
- u32 diff;
-
- /* This assumes that atomic_t has at least as many bits as u32 */
- diff = ring->w_alloc_ctr - (u32) atomic_read(&ring->w_free_ctr);
- BUG_ON(diff > ring->w_nr);
-
- return diff;
-}
-
-void rds_iw_ring_resize(struct rds_iw_work_ring *ring, u32 nr)
-{
- /* We only ever get called from the connection setup code,
- * prior to creating the QP. */
- BUG_ON(__rds_iw_ring_used(ring));
- ring->w_nr = nr;
-}
-
-static int __rds_iw_ring_empty(struct rds_iw_work_ring *ring)
-{
- return __rds_iw_ring_used(ring) == 0;
-}
-
-u32 rds_iw_ring_alloc(struct rds_iw_work_ring *ring, u32 val, u32 *pos)
-{
- u32 ret = 0, avail;
-
- avail = ring->w_nr - __rds_iw_ring_used(ring);
-
- rdsdebug("ring %p val %u next %u free %u\n", ring, val,
- ring->w_alloc_ptr, avail);
-
- if (val && avail) {
- ret = min(val, avail);
- *pos = ring->w_alloc_ptr;
-
- ring->w_alloc_ptr = (ring->w_alloc_ptr + ret) % ring->w_nr;
- ring->w_alloc_ctr += ret;
- }
-
- return ret;
-}
-
-void rds_iw_ring_free(struct rds_iw_work_ring *ring, u32 val)
-{
- ring->w_free_ptr = (ring->w_free_ptr + val) % ring->w_nr;
- atomic_add(val, &ring->w_free_ctr);
-
- if (__rds_iw_ring_empty(ring) &&
- waitqueue_active(&rds_iw_ring_empty_wait))
- wake_up(&rds_iw_ring_empty_wait);
-}
-
-void rds_iw_ring_unalloc(struct rds_iw_work_ring *ring, u32 val)
-{
- ring->w_alloc_ptr = (ring->w_alloc_ptr - val) % ring->w_nr;
- ring->w_alloc_ctr -= val;
-}
-
-int rds_iw_ring_empty(struct rds_iw_work_ring *ring)
-{
- return __rds_iw_ring_empty(ring);
-}
-
-int rds_iw_ring_low(struct rds_iw_work_ring *ring)
-{
- return __rds_iw_ring_used(ring) <= (ring->w_nr >> 1);
-}
-
-
-/*
- * returns the oldest alloced ring entry. This will be the next one
- * freed. This can't be called if there are none allocated.
- */
-u32 rds_iw_ring_oldest(struct rds_iw_work_ring *ring)
-{
- return ring->w_free_ptr;
-}
-
-/*
- * returns the number of completed work requests.
- */
-
-u32 rds_iw_ring_completed(struct rds_iw_work_ring *ring, u32 wr_id, u32 oldest)
-{
- u32 ret;
-
- if (oldest <= (unsigned long long)wr_id)
- ret = (unsigned long long)wr_id - oldest + 1;
- else
- ret = ring->w_nr - oldest + (unsigned long long)wr_id + 1;
-
- rdsdebug("ring %p ret %u wr_id %u oldest %u\n", ring, ret,
- wr_id, oldest);
- return ret;
-}
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