linux-imx

/*

 * raid_class.c - implementation of a simple raid visualisation class

 *

 * Copyright (c) 2005 - James Bottomley <James.Bottomley@steeleye.com>

 *

 * This file is licensed under GPLv2

 *

 * This class is designed to allow raid attributes to be visualised and

 * manipulated in a form independent of the underlying raid.  Ultimately this

 * should work for both hardware and software raids.

 */

#include <linux/init.h>

#include <linux/module.h>

#include <linux/list.h>

#include <linux/slab.h>

#include <linux/string.h>

#include <linux/raid_class.h>

#include <scsi/scsi_device.h>

#include <scsi/scsi_host.h>

​

#define RAID_NUM_ATTRS  3

​

struct raid_internal {

    struct raid_template r;

    struct raid_function_template *f;

    /* The actual attributes */

    struct device_attribute private_attrs[RAID_NUM_ATTRS];

    /* The array of null terminated pointers to attributes 

     * needed by scsi_sysfs.c */

    struct device_attribute *attrs[RAID_NUM_ATTRS + 1];

};

​

struct raid_component {

    struct list_head node;

    struct device dev;

    int num;

};

​

#define to_raid_internal(tmpl)  container_of(tmpl, struct raid_internal, r)

​

#define tc_to_raid_internal(tcont) ({                   \

    struct raid_template *r =                   \

        container_of(tcont, struct raid_template, raid_attrs);  \

    to_raid_internal(r);                        \

})

​

#define ac_to_raid_internal(acont) ({                   \

    struct transport_container *tc =                \

        container_of(acont, struct transport_container, ac);    \

    tc_to_raid_internal(tc);                    \

})

​

#define device_to_raid_internal(dev) ({             \

    struct attribute_container *ac =                \

        attribute_container_classdev_to_container(dev); \

    ac_to_raid_internal(ac);                    \

})

​

static int raid_match(struct attribute_container *cont, struct device *dev)

{

    /* We have to look for every subsystem that could house

     * emulated RAID devices, so start with SCSI */

    struct raid_internal *i = ac_to_raid_internal(cont);

​

    if (IS_ENABLED(CONFIG_SCSI) && scsi_is_sdev_device(dev)) {

        struct scsi_device *sdev = to_scsi_device(dev);

​

        if (i->f->cookie != sdev->host->hostt)

            return 0;

​

        return i->f->is_raid(dev);

    }

    /* FIXME: look at other subsystems too */

    return 0;

}

​

static int raid_setup(struct transport_container *tc, struct device *dev,

               struct device *cdev)

{

    struct raid_data *rd;

​

    BUG_ON(dev_get_drvdata(cdev));

​

    rd = kzalloc(sizeof(*rd), GFP_KERNEL);

    if (!rd)

        return -ENOMEM;

​

    INIT_LIST_HEAD(&rd->component_list);

    dev_set_drvdata(cdev, rd);

    return 0;