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authorLinus Torvalds <torvalds@linux-foundation.org>2012-05-21 17:54:55 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-05-21 17:54:55 -0700
commitc23ddf7857bdb2e8001b0a058603497c765a580d (patch)
treef1d826612114a17d6ab543b7095adf04b5ba614a /drivers/infiniband/hw/cxgb4/id_table.c
parentda4f58ffa08a7b7012fab9c205fa0f6ba40fec42 (diff)
parentcc169165c82e14ea43e313f937a0a475ca97e588 (diff)
downloadlinux-c23ddf7857bdb2e8001b0a058603497c765a580d.tar.bz2
Merge tag 'rdma-for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband
Pull InfiniBand/RDMA changes from Roland Dreier: - Add ocrdma hardware driver for Emulex IB-over-Ethernet adapters - Add generic and mlx4 support for "raw" QPs: allow suitably privileged applications to send and receive arbitrary packets directly to/from the hardware - Add "doorbell drop" handling to the cxgb4 driver - A fairly large batch of qib hardware driver changes - A few fixes for lockdep-detected issues - A few other miscellaneous fixes and cleanups Fix up trivial conflict in drivers/net/ethernet/emulex/benet/be.h. * tag 'rdma-for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband: (53 commits) RDMA/cxgb4: Include vmalloc.h for vmalloc and vfree IB/mlx4: Fix mlx4_ib_add() error flow IB/core: Fix IB_SA_COMP_MASK macro IB/iser: Fix error flow in iser ep connection establishment IB/mlx4: Increase the number of vectors (EQs) available for ULPs RDMA/cxgb4: Add query_qp support RDMA/cxgb4: Remove kfifo usage RDMA/cxgb4: Use vmalloc() for debugfs QP dump RDMA/cxgb4: DB Drop Recovery for RDMA and LLD queues RDMA/cxgb4: Disable interrupts in c4iw_ev_dispatch() RDMA/cxgb4: Add DB Overflow Avoidance RDMA/cxgb4: Add debugfs RDMA memory stats cxgb4: DB Drop Recovery for RDMA and LLD queues cxgb4: Common platform specific changes for DB Drop Recovery cxgb4: Detect DB FULL events and notify RDMA ULD RDMA/cxgb4: Drop peer_abort when no endpoint found RDMA/cxgb4: Always wake up waiters in c4iw_peer_abort_intr() mlx4_core: Change bitmap allocator to work in round-robin fashion RDMA/nes: Don't call event handler if pointer is NULL RDMA/nes: Fix for the ORD value of the connecting peer ...
Diffstat (limited to 'drivers/infiniband/hw/cxgb4/id_table.c')
-rw-r--r--drivers/infiniband/hw/cxgb4/id_table.c112
1 files changed, 112 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/cxgb4/id_table.c b/drivers/infiniband/hw/cxgb4/id_table.c
new file mode 100644
index 000000000000..f95e5df30db2
--- /dev/null
+++ b/drivers/infiniband/hw/cxgb4/id_table.c
@@ -0,0 +1,112 @@
+/*
+ * Copyright (c) 2011 Chelsio Communications. 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 <linux/random.h>
+#include "iw_cxgb4.h"
+
+#define RANDOM_SKIP 16
+
+/*
+ * Trivial bitmap-based allocator. If the random flag is set, the
+ * allocator is designed to:
+ * - pseudo-randomize the id returned such that it is not trivially predictable.
+ * - avoid reuse of recently used id (at the expense of predictability)
+ */
+u32 c4iw_id_alloc(struct c4iw_id_table *alloc)
+{
+ unsigned long flags;
+ u32 obj;
+
+ spin_lock_irqsave(&alloc->lock, flags);
+
+ obj = find_next_zero_bit(alloc->table, alloc->max, alloc->last);
+ if (obj >= alloc->max)
+ obj = find_first_zero_bit(alloc->table, alloc->max);
+
+ if (obj < alloc->max) {
+ if (alloc->flags & C4IW_ID_TABLE_F_RANDOM)
+ alloc->last += random32() % RANDOM_SKIP;
+ else
+ alloc->last = obj + 1;
+ if (alloc->last >= alloc->max)
+ alloc->last = 0;
+ set_bit(obj, alloc->table);
+ obj += alloc->start;
+ } else
+ obj = -1;
+
+ spin_unlock_irqrestore(&alloc->lock, flags);
+ return obj;
+}
+
+void c4iw_id_free(struct c4iw_id_table *alloc, u32 obj)
+{
+ unsigned long flags;
+
+ obj -= alloc->start;
+ BUG_ON((int)obj < 0);
+
+ spin_lock_irqsave(&alloc->lock, flags);
+ clear_bit(obj, alloc->table);
+ spin_unlock_irqrestore(&alloc->lock, flags);
+}
+
+int c4iw_id_table_alloc(struct c4iw_id_table *alloc, u32 start, u32 num,
+ u32 reserved, u32 flags)
+{
+ int i;
+
+ alloc->start = start;
+ alloc->flags = flags;
+ if (flags & C4IW_ID_TABLE_F_RANDOM)
+ alloc->last = random32() % RANDOM_SKIP;
+ else
+ alloc->last = 0;
+ alloc->max = num;
+ spin_lock_init(&alloc->lock);
+ alloc->table = kmalloc(BITS_TO_LONGS(num) * sizeof(long),
+ GFP_KERNEL);
+ if (!alloc->table)
+ return -ENOMEM;
+
+ bitmap_zero(alloc->table, num);
+ if (!(alloc->flags & C4IW_ID_TABLE_F_EMPTY))
+ for (i = 0; i < reserved; ++i)
+ set_bit(i, alloc->table);
+
+ return 0;
+}
+
+void c4iw_id_table_free(struct c4iw_id_table *alloc)
+{
+ kfree(alloc->table);
+}