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e6550b3ee1
Based on the normalized pattern:
this program is free software you may redistribute it and/or modify it
under the terms of the gnu general public license as published by the
free software foundation version 2 of the license 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
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
64 lines
1.8 KiB
C
64 lines
1.8 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
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/* Copyright 2014 Cisco Systems, Inc. All rights reserved. */
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#ifndef _CQ_DESC_H_
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#define _CQ_DESC_H_
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/*
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* Completion queue descriptor types
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*/
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enum cq_desc_types {
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CQ_DESC_TYPE_WQ_ENET = 0,
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CQ_DESC_TYPE_DESC_COPY = 1,
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CQ_DESC_TYPE_WQ_EXCH = 2,
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CQ_DESC_TYPE_RQ_ENET = 3,
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CQ_DESC_TYPE_RQ_FCP = 4,
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};
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/* Completion queue descriptor: 16B
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*
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* All completion queues have this basic layout. The
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* type_specific area is unique for each completion
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* queue type.
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*/
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struct cq_desc {
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__le16 completed_index;
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__le16 q_number;
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u8 type_specific[11];
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u8 type_color;
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};
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#define CQ_DESC_TYPE_BITS 4
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#define CQ_DESC_TYPE_MASK ((1 << CQ_DESC_TYPE_BITS) - 1)
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#define CQ_DESC_COLOR_MASK 1
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#define CQ_DESC_COLOR_SHIFT 7
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#define CQ_DESC_Q_NUM_BITS 10
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#define CQ_DESC_Q_NUM_MASK ((1 << CQ_DESC_Q_NUM_BITS) - 1)
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#define CQ_DESC_COMP_NDX_BITS 12
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#define CQ_DESC_COMP_NDX_MASK ((1 << CQ_DESC_COMP_NDX_BITS) - 1)
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static inline void cq_desc_dec(const struct cq_desc *desc_arg,
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u8 *type, u8 *color, u16 *q_number, u16 *completed_index)
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{
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const struct cq_desc *desc = desc_arg;
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const u8 type_color = desc->type_color;
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*color = (type_color >> CQ_DESC_COLOR_SHIFT) & CQ_DESC_COLOR_MASK;
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/*
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* Make sure color bit is read from desc *before* other fields
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* are read from desc. Hardware guarantees color bit is last
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* bit (byte) written. Adding the rmb() prevents the compiler
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* and/or CPU from reordering the reads which would potentially
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* result in reading stale values.
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*/
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rmb();
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*type = type_color & CQ_DESC_TYPE_MASK;
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*q_number = le16_to_cpu(desc->q_number) & CQ_DESC_Q_NUM_MASK;
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*completed_index = le16_to_cpu(desc->completed_index) &
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CQ_DESC_COMP_NDX_MASK;
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}
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#endif /* _CQ_DESC_H_ */
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