linux-imx

// SPDX-License-Identifier: GPL-2.0+

/*

 * XArray implementation

 * Copyright (c) 2017 Microsoft Corporation

 * Author: Matthew Wilcox <willy@infradead.org>

 */

​

#include <linux/bitmap.h>

#include <linux/export.h>

#include <linux/list.h>

#include <linux/slab.h>

#include <linux/xarray.h>

​

/*

 * Coding conventions in this file:

 *

 * @xa is used to refer to the entire xarray.

 * @xas is the 'xarray operation state'.  It may be either a pointer to

 * an xa_state, or an xa_state stored on the stack.  This is an unfortunate

 * ambiguity.

 * @index is the index of the entry being operated on

 * @mark is an xa_mark_t; a small number indicating one of the mark bits.

 * @node refers to an xa_node; usually the primary one being operated on by

 * this function.

 * @offset is the index into the slots array inside an xa_node.

 * @parent refers to the @xa_node closer to the head than @node.

 * @entry refers to something stored in a slot in the xarray

 */

​

static inline unsigned int xa_lock_type(const struct xarray *xa)

{

    return (__force unsigned int)xa->xa_flags & 3;

}

​

static inline void xas_lock_type(struct xa_state *xas, unsigned int lock_type)

{

    if (lock_type == XA_LOCK_IRQ)

        xas_lock_irq(xas);

    else if (lock_type == XA_LOCK_BH)

        xas_lock_bh(xas);

    else

        xas_lock(xas);

}

​

static inline void xas_unlock_type(struct xa_state *xas, unsigned int lock_type)

{

    if (lock_type == XA_LOCK_IRQ)

        xas_unlock_irq(xas);

    else if (lock_type == XA_LOCK_BH)

        xas_unlock_bh(xas);

    else

        xas_unlock(xas);

}

​

static inline bool xa_track_free(const struct xarray *xa)

{

    return xa->xa_flags & XA_FLAGS_TRACK_FREE;

}

​

static inline bool xa_zero_busy(const struct xarray *xa)

{

    return xa->xa_flags & XA_FLAGS_ZERO_BUSY;

}