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+/*
+ * Copyright (c) 2012-2016 VMware, Inc. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of EITHER the GNU General Public License
+ * version 2 as published by the Free Software Foundation or the BSD
+ * 2-Clause License. This program is distributed in the hope that it
+ * will be useful, but WITHOUT ANY WARRANTY; WITHOUT EVEN THE IMPLIED
+ * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License version 2 for more details at
+ * http://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program available in the file COPYING in the main
+ * directory of this source tree.
+ *
+ * The BSD 2-Clause License
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/bitmap.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+
+#include "pvrdma.h"
+
+int pvrdma_uar_table_init(struct pvrdma_dev *dev)
+{
+ u32 num = dev->dsr->caps.max_uar;
+ u32 mask = num - 1;
+ struct pvrdma_id_table *tbl = &dev->uar_table.tbl;
+
+ if (!is_power_of_2(num))
+ return -EINVAL;
+
+ tbl->last = 0;
+ tbl->top = 0;
+ tbl->max = num;
+ tbl->mask = mask;
+ spin_lock_init(&tbl->lock);
+ tbl->table = kcalloc(BITS_TO_LONGS(num), sizeof(long), GFP_KERNEL);
+ if (!tbl->table)
+ return -ENOMEM;
+
+ /* 0th UAR is taken by the device. */
+ set_bit(0, tbl->table);
+
+ return 0;
+}
+
+void pvrdma_uar_table_cleanup(struct pvrdma_dev *dev)
+{
+ struct pvrdma_id_table *tbl = &dev->uar_table.tbl;
+
+ kfree(tbl->table);
+}
+
+int pvrdma_uar_alloc(struct pvrdma_dev *dev, struct pvrdma_uar_map *uar)
+{
+ struct pvrdma_id_table *tbl;
+ unsigned long flags;
+ u32 obj;
+
+ tbl = &dev->uar_table.tbl;
+
+ spin_lock_irqsave(&tbl->lock, flags);
+ obj = find_next_zero_bit(tbl->table, tbl->max, tbl->last);
+ if (obj >= tbl->max) {
+ tbl->top = (tbl->top + tbl->max) & tbl->mask;
+ obj = find_first_zero_bit(tbl->table, tbl->max);
+ }
+
+ if (obj >= tbl->max) {
+ spin_unlock_irqrestore(&tbl->lock, flags);
+ return -ENOMEM;
+ }
+
+ set_bit(obj, tbl->table);
+ obj |= tbl->top;
+
+ spin_unlock_irqrestore(&tbl->lock, flags);
+
+ uar->index = obj;
+ uar->pfn = (pci_resource_start(dev->pdev, PVRDMA_PCI_RESOURCE_UAR) >>
+ PAGE_SHIFT) + uar->index;
+
+ return 0;
+}
+
+void pvrdma_uar_free(struct pvrdma_dev *dev, struct pvrdma_uar_map *uar)
+{
+ struct pvrdma_id_table *tbl = &dev->uar_table.tbl;
+ unsigned long flags;
+ u32 obj;
+
+ obj = uar->index & (tbl->max - 1);
+ spin_lock_irqsave(&tbl->lock, flags);
+ clear_bit(obj, tbl->table);
+ tbl->last = min(tbl->last, obj);
+ tbl->top = (tbl->top + tbl->max) & tbl->mask;
+ spin_unlock_irqrestore(&tbl->lock, flags);
+}