45 lines
1.3 KiB
C
45 lines
1.3 KiB
C
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// SPDX-License-Identifier: GPL-2.0+
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/*
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* XArray implementation
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* Copyright (c) 2017 Microsoft Corporation
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* Author: Matthew Wilcox <willy@infradead.org>
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*/
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#include <linux/export.h>
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#include <linux/xarray.h>
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/*
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* Coding conventions in this file:
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*
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* @xa is used to refer to the entire xarray.
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* @xas is the 'xarray operation state'. It may be either a pointer to
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* an xa_state, or an xa_state stored on the stack. This is an unfortunate
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* ambiguity.
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* @index is the index of the entry being operated on
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* @mark is an xa_mark_t; a small number indicating one of the mark bits.
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* @node refers to an xa_node; usually the primary one being operated on by
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* this function.
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* @offset is the index into the slots array inside an xa_node.
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* @parent refers to the @xa_node closer to the head than @node.
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* @entry refers to something stored in a slot in the xarray
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*/
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/**
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* xa_init_flags() - Initialise an empty XArray with flags.
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* @xa: XArray.
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* @flags: XA_FLAG values.
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*
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* If you need to initialise an XArray with special flags (eg you need
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* to take the lock from interrupt context), use this function instead
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* of xa_init().
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*
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* Context: Any context.
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*/
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void xa_init_flags(struct xarray *xa, gfp_t flags)
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{
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spin_lock_init(&xa->xa_lock);
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xa->xa_flags = flags;
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xa->xa_head = NULL;
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}
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EXPORT_SYMBOL(xa_init_flags);
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