1 files changed, 179 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/mthca/mthca_allocator.c b/drivers/infiniband/hw/mthca/mthca_allocator.c
new file mode 100644
index 000000000000..b1db48dd91d6
--- /dev/null
+++ b/drivers/infiniband/hw/mthca/mthca_allocator.c
@@ -0,0 +1,179 @@
+/*
+ * Copyright (c) 2004 Topspin 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.
+ *
+ * $Id: mthca_allocator.c 1349 2004-12-16 21:09:43Z roland $
+ */
+
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/bitmap.h>
+
+#include "mthca_dev.h"
+
+/* Trivial bitmap-based allocator */
+u32 mthca_alloc(struct mthca_alloc *alloc)
+{
+	u32 obj;
+
+	spin_lock(&alloc->lock);
+	obj = find_next_zero_bit(alloc->table, alloc->max, alloc->last);
+	if (obj >= alloc->max) {
+		alloc->top = (alloc->top + alloc->max) & alloc->mask;
+		obj = find_first_zero_bit(alloc->table, alloc->max);
+	}
+
+	if (obj < alloc->max) {
+		set_bit(obj, alloc->table);
+		obj |= alloc->top;
+	} else
+		obj = -1;
+
+	spin_unlock(&alloc->lock);
+
+	return obj;
+}
+
+void mthca_free(struct mthca_alloc *alloc, u32 obj)
+{
+	obj &= alloc->max - 1;
+	spin_lock(&alloc->lock);
+	clear_bit(obj, alloc->table);
+	alloc->last = min(alloc->last, obj);
+	alloc->top = (alloc->top + alloc->max) & alloc->mask;
+	spin_unlock(&alloc->lock);
+}
+
+int mthca_alloc_init(struct mthca_alloc *alloc, u32 num, u32 mask,
+		     u32 reserved)
+{
+	int i;
+
+	/* num must be a power of 2 */
+	if (num != 1 << (ffs(num) - 1))
+		return -EINVAL;
+
+	alloc->last = 0;
+	alloc->top  = 0;
+	alloc->max  = num;
+	alloc->mask = mask;
+	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);
+	for (i = 0; i < reserved; ++i)
+		set_bit(i, alloc->table);
+
+	return 0;
+}
+
+void mthca_alloc_cleanup(struct mthca_alloc *alloc)
+{
+	kfree(alloc->table);
+}
+
+/*
+ * Array of pointers with lazy allocation of leaf pages.  Callers of
+ * _get, _set and _clear methods must use a lock or otherwise
+ * serialize access to the array.
+ */
+
+void *mthca_array_get(struct mthca_array *array, int index)
+{
+	int p = (index * sizeof (void *)) >> PAGE_SHIFT;
+
+	if (array->page_list[p].page) {
+		int i = index & (PAGE_SIZE / sizeof (void *) - 1);
+		return array->page_list[p].page[i];
+	} else
+		return NULL;
+}
+
+int mthca_array_set(struct mthca_array *array, int index, void *value)
+{
+	int p = (index * sizeof (void *)) >> PAGE_SHIFT;
+
+	/* Allocate with GFP_ATOMIC because we'll be called with locks held. */
+	if (!array->page_list[p].page)
+		array->page_list[p].page = (void **) get_zeroed_page(GFP_ATOMIC);
+
+	if (!array->page_list[p].page)
+		return -ENOMEM;
+
+	array->page_list[p].page[index & (PAGE_SIZE / sizeof (void *) - 1)] =
+		value;
+	++array->page_list[p].used;
+
+	return 0;
+}
+
+void mthca_array_clear(struct mthca_array *array, int index)
+{
+	int p = (index * sizeof (void *)) >> PAGE_SHIFT;
+
+	if (--array->page_list[p].used == 0) {
+		free_page((unsigned long) array->page_list[p].page);
+		array->page_list[p].page = NULL;
+	}
+
+	if (array->page_list[p].used < 0)
+		pr_debug("Array %p index %d page %d with ref count %d < 0\n",
+			 array, index, p, array->page_list[p].used);
+}
+
+int mthca_array_init(struct mthca_array *array, int nent)
+{
+	int npage = (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE;
+	int i;
+
+	array->page_list = kmalloc(npage * sizeof *array->page_list, GFP_KERNEL);
+	if (!array->page_list)
+		return -ENOMEM;
+
+	for (i = 0; i < npage; ++i) {
+		array->page_list[i].page = NULL;
+		array->page_list[i].used = 0;
+	}
+
+	return 0;
+}
+
+void mthca_array_cleanup(struct mthca_array *array, int nent)
+{
+	int i;
+
+	for (i = 0; i < (nent * sizeof (void *) + PAGE_SIZE - 1) / PAGE_SIZE; ++i)
+		free_page((unsigned long) array->page_list[i].page);
+
+	kfree(array->page_list);
+}