linux-imx

/*

 * Copyright (C) 2001-2003 Sistina Software (UK) Limited.

 *

 * This file is released under the GPL.

 */

​

#include "dm.h"

#include <linux/device-mapper.h>

​

#include <linux/module.h>

#include <linux/init.h>

#include <linux/blkdev.h>

#include <linux/bio.h>

#include <linux/dax.h>

#include <linux/slab.h>

#include <linux/log2.h>

​

#define DM_MSG_PREFIX "striped"

#define DM_IO_ERROR_THRESHOLD 15

​

struct stripe {

    struct dm_dev *dev;

    sector_t physical_start;

​

    atomic_t error_count;

};

​

struct stripe_c {

    uint32_t stripes;

    int stripes_shift;

​

    /* The size of this target / num. stripes */

    sector_t stripe_width;

​

    uint32_t chunk_size;

    int chunk_size_shift;

​

    /* Needed for handling events */

    struct dm_target *ti;

​

    /* Work struct used for triggering events*/

    struct work_struct trigger_event;

​

    struct stripe stripe[0];

};

​

/*

 * An event is triggered whenever a drive

 * drops out of a stripe volume.

 */

static void trigger_event(struct work_struct *work)

{

    struct stripe_c *sc = container_of(work, struct stripe_c,

                       trigger_event);

    dm_table_event(sc->ti->table);

}

​

static inline struct stripe_c *alloc_context(unsigned int stripes)

{

    size_t len;

​

    if (dm_array_too_big(sizeof(struct stripe_c), sizeof(struct stripe),

                 stripes))

        return NULL;

​

    len = sizeof(struct stripe_c) + (sizeof(struct stripe) * stripes);

​

    return kmalloc(len, GFP_KERNEL);

}

​

/*

 * Parse a single <dev> <sector> pair

 */

static int get_stripe(struct dm_target *ti, struct stripe_c *sc,

              unsigned int stripe, char **argv)

{

    unsigned long long start;

    char dummy;

    int ret;

​

    if (sscanf(argv[1], "%llu%c", &start, &dummy) != 1)

        return -EINVAL;

​

    ret = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table),

                &sc->stripe[stripe].dev);

    if (ret)

        return ret;

​

    sc->stripe[stripe].physical_start = start;

​

    return 0;

}