linux-imx

/*

 * Copyright (C) 2001 Sistina Software (UK) Limited.

 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.

 *

 * This file is released under the GPL.

 */

​

#include "dm-core.h"

​

#include <linux/module.h>

#include <linux/vmalloc.h>

#include <linux/blkdev.h>

#include <linux/namei.h>

#include <linux/ctype.h>

#include <linux/string.h>

#include <linux/slab.h>

#include <linux/interrupt.h>

#include <linux/mutex.h>

#include <linux/delay.h>

#include <linux/atomic.h>

#include <linux/blk-mq.h>

#include <linux/mount.h>

#include <linux/dax.h>

​

#define DM_MSG_PREFIX "table"

​

#define MAX_DEPTH 16

#define NODE_SIZE L1_CACHE_BYTES

#define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t))

#define CHILDREN_PER_NODE (KEYS_PER_NODE + 1)

​

struct dm_table {

    struct mapped_device *md;

    enum dm_queue_mode type;

​

    /* btree table */

    unsigned int depth;

    unsigned int counts[MAX_DEPTH]; /* in nodes */

    sector_t *index[MAX_DEPTH];

​

    unsigned int num_targets;

    unsigned int num_allocated;

    sector_t *highs;

    struct dm_target *targets;

​

    struct target_type *immutable_target_type;

​

    bool integrity_supported:1;

    bool singleton:1;

    unsigned integrity_added:1;

​

    /*

     * Indicates the rw permissions for the new logical

     * device.  This should be a combination of FMODE_READ

     * and FMODE_WRITE.

     */

    fmode_t mode;

​

    /* a list of devices used by this table */

    struct list_head devices;

​

    /* events get handed up using this callback */

    void (*event_fn)(void *);

    void *event_context;

​

    struct dm_md_mempools *mempools;

​

    struct list_head target_callbacks;

};

​

/*

 * Similar to ceiling(log_size(n))

 */

static unsigned int int_log(unsigned int n, unsigned int base)

{

    int result = 0;

​

    while (n > 1) {

        n = dm_div_up(n, base);

        result++;

    }

​

    return result;

}

​

/*

 * Calculate the index of the child node of the n'th node k'th key.

 */

static inline unsigned int get_child(unsigned int n, unsigned int k)

{

    return (n * CHILDREN_PER_NODE) + k;

}