Bitmap allocation service is currently used for assigning
Protection Domain (PD) numbers.
Signed-off-by: Gal Pressman <galpress@xxxxxxxxxx>
---
drivers/infiniband/hw/efa/efa_bitmap.c | 76 ++++++++++++++++++++++++++++++++++
1 file changed, 76 insertions(+)
create mode 100644 drivers/infiniband/hw/efa/efa_bitmap.c
diff --git a/drivers/infiniband/hw/efa/efa_bitmap.c b/drivers/infiniband/hw/efa/efa_bitmap.c
new file mode 100644
index 000000000000..251cc68d25f5
--- /dev/null
+++ b/drivers/infiniband/hw/efa/efa_bitmap.c
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+/*
+ * Copyright 2006, 2007 Cisco Systems, Inc. All rights reserved.
+ * Copyright 2007, 2008 Mellanox Technologies. All rights reserved.
+ * Copyright 2018 Amazon.com, Inc. or its affiliates.
+ */
+
+#include <linux/bitmap.h>
+
+#include "efa.h"
+
+u32 efa_bitmap_alloc(struct efa_bitmap *bitmap)
+{
+ u32 obj;
+
+ spin_lock(&bitmap->lock);
+
+ obj = find_next_zero_bit(bitmap->table, bitmap->max, bitmap->last);
+ if (obj >= bitmap->max)
+ obj = find_first_zero_bit(bitmap->table, bitmap->max);
+
+ if (obj < bitmap->max) {
+ set_bit(obj, bitmap->table);
+ bitmap->last = obj + 1;
+ if (bitmap->last == bitmap->max)
+ bitmap->last = 0;
+ } else {
+ obj = EFA_BITMAP_INVAL;
+ }
+
+ if (obj != EFA_BITMAP_INVAL)
+ --bitmap->avail;
+
+ spin_unlock(&bitmap->lock);
+
+ return obj;
+}
+
+void efa_bitmap_free(struct efa_bitmap *bitmap, u32 obj)
+{
+ obj &= bitmap->mask;
+
+ spin_lock(&bitmap->lock);
+ bitmap_clear(bitmap->table, obj, 1);
+ bitmap->avail++;
+ spin_unlock(&bitmap->lock);
+}
+
+u32 efa_bitmap_avail(struct efa_bitmap *bitmap)
+{
+ return bitmap->avail;
+}
+
+int efa_bitmap_init(struct efa_bitmap *bitmap, u32 num)
+{
+ /* num must be a power of 2 */
+ if (!is_power_of_2(num))
+ return -EINVAL;
+
+ bitmap->last = 0;
+ bitmap->max = num;
+ bitmap->mask = num - 1;
+ bitmap->avail = num;
+ spin_lock_init(&bitmap->lock);
+ bitmap->table = kcalloc(BITS_TO_LONGS(bitmap->max),
+ sizeof(long), GFP_KERNEL);
+ if (!bitmap->table)
+ return -ENOMEM;
+
+ return 0;
+}
+
+void efa_bitmap_cleanup(struct efa_bitmap *bitmap)
+{
+ kfree(bitmap->table);
+}
--
2.7.4
