linux-imx

/*

 * Copyright(c) 2017 Intel Corporation. All rights reserved.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of version 2 of the GNU General Public License as

 * published by the Free Software Foundation.

 *

 * 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 for more details.

 */

#include <linux/pagemap.h>

#include <linux/module.h>

#include <linux/mount.h>

#include <linux/magic.h>

#include <linux/genhd.h>

#include <linux/pfn_t.h>

#include <linux/cdev.h>

#include <linux/hash.h>

#include <linux/slab.h>

#include <linux/uio.h>

#include <linux/dax.h>

#include <linux/fs.h>

#include "dax-private.h"

​

static dev_t dax_devt;

DEFINE_STATIC_SRCU(dax_srcu);

static struct vfsmount *dax_mnt;

static DEFINE_IDA(dax_minor_ida);

static struct kmem_cache *dax_cache __read_mostly;

static struct super_block *dax_superblock __read_mostly;

​

#define DAX_HASH_SIZE (PAGE_SIZE / sizeof(struct hlist_head))

static struct hlist_head dax_host_list[DAX_HASH_SIZE];

static DEFINE_SPINLOCK(dax_host_lock);

​

int dax_read_lock(void)

{

    return srcu_read_lock(&dax_srcu);

}

EXPORT_SYMBOL_GPL(dax_read_lock);

​

void dax_read_unlock(int id)

{

    srcu_read_unlock(&dax_srcu, id);

}

EXPORT_SYMBOL_GPL(dax_read_unlock);

​

#ifdef CONFIG_BLOCK

#include <linux/blkdev.h>

​

int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size,

        pgoff_t *pgoff)

{

    phys_addr_t phys_off = (get_start_sect(bdev) + sector) * 512;

​

    if (pgoff)

        *pgoff = PHYS_PFN(phys_off);

    if (phys_off % PAGE_SIZE || size % PAGE_SIZE)

        return -EINVAL;

    return 0;

}