diff options
Diffstat (limited to 'drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c')
| -rw-r--r-- | drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c b/drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c new file mode 100644 index 000000000..9a4de962e --- /dev/null +++ b/drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c @@ -0,0 +1,127 @@ +/* + * 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 = bitmap_zalloc(num, 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; + + bitmap_free(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); +} |