/*
 * Block driver for media (i.e., flash cards)
 *
 * Copyright 2002 Hewlett-Packard Company
 * Copyright 2005-2008 Pierre Ossman
 *
 * Use consistent with the GNU GPL is permitted,
 * provided that this copyright notice is
 * preserved in its entirety in all copies and derived works.
 *
 * HEWLETT-PACKARD COMPANY MAKES NO WARRANTIES, EXPRESSED OR IMPLIED,
 * AS TO THE USEFULNESS OR CORRECTNESS OF THIS CODE OR ITS
 * FITNESS FOR ANY PARTICULAR PURPOSE.
 *
 * Many thanks to Alessandro Rubini and Jonathan Corbet!
 *
 * Author:  Andrew Christian
 *          28 May 2002
 */
#include <linux/moduleparam.h>
#include <linux/module.h>
#include <linux/init.h>

#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/hdreg.h>
#include <linux/kdev_t.h>
#include <linux/blkdev.h>
#include <linux/mutex.h>
#include <linux/scatterlist.h>
#include <linux/string_helpers.h>
#include <linux/delay.h>
#include <linux/capability.h>
#include <linux/compat.h>
#include <linux/pm_runtime.h>
#include <linux/idr.h>

#include <linux/mmc/ioctl.h>
#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
#include <linux/mmc/mmc.h>
#include <linux/mmc/sd.h>

#include <linux/uaccess.h>

#include "queue.h"
#include "block.h"
#include "core.h"
#include "card.h"
#include "host.h"
#include "bus.h"
#include "mmc_ops.h"
#include "quirks.h"
#include "sd_ops.h"

MODULE_ALIAS("mmc:block");
#ifdef MODULE_PARAM_PREFIX
#undef MODULE_PARAM_PREFIX
#endif
#define MODULE_PARAM_PREFIX "mmcblk."

#define MMC_BLK_TIMEOUT_MS  (10 * 60 * 1000)        /* 10 minute timeout */
#define MMC_SANITIZE_REQ_TIMEOUT 240000
#define MMC_EXTRACT_INDEX_FROM_ARG(x) ((x & 0x00FF0000) >> 16)

#define mmc_req_rel_wr(req)     ((req->cmd_flags & REQ_FUA) && \
                                  (rq_data_dir(req) == WRITE))
static DEFINE_MUTEX(block_mutex);

/*
 * The defaults come from config options but can be overriden by module
 * or bootarg options.
 */
static int perdev_minors = CONFIG_MMC_BLOCK_MINORS;

/*
 * We've only got one major, so number of mmcblk devices is
 * limited to (1 << 20) / number of minors per device.  It is also
 * limited by the MAX_DEVICES below.
 */
static int max_devices;

#define MAX_DEVICES 256

static DEFINE_IDA(mmc_blk_ida);

/*
 * There is one mmc_blk_data per slot.
 */
struct mmc_blk_data {
        spinlock_t      lock;
        struct device   *parent;
        struct gendisk  *disk;
        struct mmc_queue queue;
        struct list_head part;

        unsigned int    flags;
#define MMC_BLK_CMD23   (1 << 0)        /* Can do SET_BLOCK_COUNT for multiblock */
#define MMC_BLK_REL_WR  (1 << 1)        /* MMC Reliable write support */

        unsigned int    usage;
        unsigned int    read_only;
        unsigned int    part_type;
        unsigned int    reset_done;
#define MMC_BLK_READ            BIT(0)
#define MMC_BLK_WRITE           BIT(1)
#define MMC_BLK_DISCARD         BIT(2)
#define MMC_BLK_SECDISCARD      BIT(3)

        /*
         * Only set in main mmc_blk_data associated
         * with mmc_card with dev_set_drvdata, and keeps
         * track of the current selected device partition.
         */
        unsigned int    part_curr;
        struct device_attribute force_ro;
        struct device_attribute power_ro_lock;
        int     area_type;
};

static DEFINE_MUTEX(open_lock);

module_param(perdev_minors, int, 0444);
MODULE_PARM_DESC(perdev_minors, "Minors numbers to allocate per device");

static inline int mmc_blk_part_switch(struct mmc_card *card,
                                      struct mmc_blk_data *md);

static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)
{
        struct mmc_blk_data *md;

        mutex_lock(&open_lock);
        md = disk->private_data;
        if (md && md->usage == 0)
                md = NULL;
        if (md)
                md->usage++;
        mutex_unlock(&open_lock);

        return md;
}

static inline int mmc_get_devidx(struct gendisk *disk)
{
        int devidx = disk->first_minor / perdev_minors;
        return devidx;
}

static void mmc_blk_put(struct mmc_blk_data *md)
{
        mutex_lock(&open_lock);
        md->usage--;
        if (md->usage == 0) {
                int devidx = mmc_get_devidx(md->disk);
                blk_cleanup_queue(md->queue.queue);
                ida_simple_remove(&mmc_blk_ida, devidx);
                put_disk(md->disk);
                kfree(md);
        }
        mutex_unlock(&open_lock);
}

static ssize_t power_ro_lock_show(struct device *dev,
                struct device_attribute *attr, char *buf)
{
        int ret;
        struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));
        struct mmc_card *card = md->queue.card;
        int locked = 0;

        if (card->ext_csd.boot_ro_lock & EXT_CSD_BOOT_WP_B_PERM_WP_EN)
                locked = 2;
        else if (card->ext_csd.boot_ro_lock & EXT_CSD_BOOT_WP_B_PWR_WP_EN)
                locked = 1;

        ret = snprintf(buf, PAGE_SIZE, "%d\n", locked);

        mmc_blk_put(md);

        return ret;
}

static ssize_t power_ro_lock_store(struct device *dev,
                struct device_attribute *attr, const char *buf, size_t count)
{
        int ret;
        struct mmc_blk_data *md, *part_md;
        struct mmc_card *card;
        struct mmc_queue *mq;
        struct request *req;
        unsigned long set;

        if (kstrtoul(buf, 0, &set))
                return -EINVAL;

        if (set != 1)
                return count;

        md = mmc_blk_get(dev_to_disk(dev));
        mq = &md->queue;
        card = md->queue.card;

        /* Dispatch locking to the block layer */
        req = blk_get_request(mq->queue, REQ_OP_DRV_OUT, __GFP_RECLAIM);
        req_to_mmc_queue_req(req)->drv_op = MMC_DRV_OP_BOOT_WP;
        blk_execute_rq(mq->queue, NULL, req, 0);
        ret = req_to_mmc_queue_req(req)->drv_op_result;

        if (!ret) {
                pr_info("%s: Locking boot partition ro until next power on\n",
                        md->disk->disk_name);
                set_disk_ro(md->disk, 1);

                list_for_each_entry(part_md, &md->part, part)
                        if (part_md->area_type == MMC_BLK_DATA_AREA_BOOT) {
                                pr_info("%s: Locking boot partition ro until next power on\n", part_md->disk->disk_name);
                                set_disk_ro(part_md->disk, 1);
                        }
        }

        mmc_blk_put(md);
        return count;
}

static ssize_t force_ro_show(struct device *dev, struct device_attribute *attr,
                             char *buf)
{
        int ret;
        struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));

        ret = snprintf(buf, PAGE_SIZE, "%d\n",
                       get_disk_ro(dev_to_disk(dev)) ^
                       md->read_only);
        mmc_blk_put(md);
        return ret;
}

static ssize_t force_ro_store(struct device *dev, struct device_attribute *attr,
                              const char *buf, size_t count)
{
        int ret;
        char *end;
        struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));
        unsigned long set = simple_strtoul(buf, &end, 0);
        if (end == buf) {
                ret = -EINVAL;
                goto out;
        }

        set_disk_ro(dev_to_disk(dev), set || md->read_only);
        ret = count;
out:
        mmc_blk_put(md);
        return ret;
}

static int mmc_blk_open(struct block_device *bdev, fmode_t mode)
{
        struct mmc_blk_data *md = mmc_blk_get(bdev->bd_disk);
        int ret = -ENXIO;

        mutex_lock(&block_mutex);
        if (md) {
                if (md->usage == 2)
                        check_disk_change(bdev);
                ret = 0;

                if ((mode & FMODE_WRITE) && md->read_only) {
                        mmc_blk_put(md);
                        ret = -EROFS;
                }
        }
        mutex_unlock(&block_mutex);

        return ret;
}

static void mmc_blk_release(struct gendisk *disk, fmode_t mode)
{
        struct mmc_blk_data *md = disk->private_data;

        mutex_lock(&block_mutex);
        mmc_blk_put(md);
        mutex_unlock(&block_mutex);
}

static int
mmc_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
        geo->cylinders = get_capacity(bdev->bd_disk) / (4 * 16);
        geo->heads = 4;
        geo->sectors = 16;
        return 0;
}

struct mmc_blk_ioc_data {
        struct mmc_ioc_cmd ic;
        unsigned char *buf;
        u64 buf_bytes;
};

static struct mmc_blk_ioc_data *mmc_blk_ioctl_copy_from_user(
        struct mmc_ioc_cmd __user *user)
{
        struct mmc_blk_ioc_data *idata;
        int err;

        idata = kmalloc(sizeof(*idata), GFP_KERNEL);
        if (!idata) {
                err = -ENOMEM;
                goto out;
        }

        if (copy_from_user(&idata->ic, user, sizeof(idata->ic))) {
                err = -EFAULT;
                goto idata_err;
        }

        idata->buf_bytes = (u64) idata->ic.blksz * idata->ic.blocks;
        if (idata->buf_bytes > MMC_IOC_MAX_BYTES) {
                err = -EOVERFLOW;
                goto idata_err;
        }

        if (!idata->buf_bytes) {
                idata->buf = NULL;
                return idata;
        }

        idata->buf = kmalloc(idata->buf_bytes, GFP_KERNEL);
        if (!idata->buf) {
                err = -ENOMEM;
                goto idata_err;
        }

        if (copy_from_user(idata->buf, (void __user *)(unsigned long)
                                        idata->ic.data_ptr, idata->buf_bytes)) {
                err = -EFAULT;
                goto copy_err;
        }

        return idata;

copy_err:
        kfree(idata->buf);
idata_err:
        kfree(idata);
out:
        return ERR_PTR(err);
}

static int mmc_blk_ioctl_copy_to_user(struct mmc_ioc_cmd __user *ic_ptr,
                                      struct mmc_blk_ioc_data *idata)
{
        struct mmc_ioc_cmd *ic = &idata->ic;

        if (copy_to_user(&(ic_ptr->response), ic->response,
                         sizeof(ic->response)))
                return -EFAULT;

        if (!idata->ic.write_flag) {
                if (copy_to_user((void __user *)(unsigned long)ic->data_ptr,
                                 idata->buf, idata->buf_bytes))
                        return -EFAULT;
        }

        return 0;
}

static int ioctl_rpmb_card_status_poll(struct mmc_card *card, u32 *status,
                                       u32 retries_max)
{
        int err;
        u32 retry_count = 0;

        if (!status || !retries_max)
                return -EINVAL;

        do {
                err = __mmc_send_status(card, status, 5);
                if (err)
                        break;

                if (!R1_STATUS(*status) &&
                                (R1_CURRENT_STATE(*status) != R1_STATE_PRG))
                        break; /* RPMB programming operation complete */

                /*
                 * Rechedule to give the MMC device a chance to continue
                 * processing the previous command without being polled too
                 * frequently.
                 */
                usleep_range(1000, 5000);
        } while (++retry_count < retries_max);

        if (retry_count == retries_max)
                err = -EPERM;

        return err;
}

static int ioctl_do_sanitize(struct mmc_card *card)
{
        int err;

        if (!mmc_can_sanitize(card)) {
                        pr_warn("%s: %s - SANITIZE is not supported\n",
                                mmc_hostname(card->host), __func__);
                        err = -EOPNOTSUPP;
                        goto out;
        }

        pr_debug("%s: %s - SANITIZE IN PROGRESS...\n",
                mmc_hostname(card->host), __func__);

        err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
                                        EXT_CSD_SANITIZE_START, 1,
                                        MMC_SANITIZE_REQ_TIMEOUT);

        if (err)
                pr_err("%s: %s - EXT_CSD_SANITIZE_START failed. err=%d\n",
                       mmc_hostname(card->host), __func__, err);

        pr_debug("%s: %s - SANITIZE COMPLETED\n", mmc_hostname(card->host),
                                             __func__);
out:
        return err;
}

static int __mmc_blk_ioctl_cmd(struct mmc_card *card, struct mmc_blk_data *md,
                               struct mmc_blk_ioc_data *idata)
{
        struct mmc_command cmd = {};
        struct mmc_data data = {};
        struct mmc_request mrq = {};
        struct scatterlist sg;
        int err;
        bool is_rpmb = false;
        u32 status = 0;

        if (!card || !md || !idata)
                return -EINVAL;

        if (md->area_type & MMC_BLK_DATA_AREA_RPMB)
                is_rpmb = true;

        cmd.opcode = idata->ic.opcode;
        cmd.arg = idata->ic.arg;
        cmd.flags = idata->ic.flags;

        if (idata->buf_bytes) {
                data.sg = &sg;
                data.sg_len = 1;
                data.blksz = idata->ic.blksz;
                data.blocks = idata->ic.blocks;

                sg_init_one(data.sg, idata->buf, idata->buf_bytes);

                if (idata->ic.write_flag)
                        data.flags = MMC_DATA_WRITE;
                else
                        data.flags = MMC_DATA_READ;

                /* data.flags must already be set before doing this. */
                mmc_set_data_timeout(&data, card);

                /* Allow overriding the timeout_ns for empirical tuning. */
                if (idata->ic.data_timeout_ns)
                        data.timeout_ns = idata->ic.data_timeout_ns;

                if ((cmd.flags & MMC_RSP_R1B) == MMC_RSP_R1B) {
                        /*
                         * Pretend this is a data transfer and rely on the
                         * host driver to compute timeout.  When all host
                         * drivers support cmd.cmd_timeout for R1B, this
                         * can be changed to:
                         *
                         *     mrq.data = NULL;
                         *     cmd.cmd_timeout = idata->ic.cmd_timeout_ms;
                         */
                        data.timeout_ns = idata->ic.cmd_timeout_ms * 1000000;
                }

                mrq.data = &data;
        }

        mrq.cmd = &cmd;

        err = mmc_blk_part_switch(card, md);
        if (err)
                return err;

        if (idata->ic.is_acmd) {
                err = mmc_app_cmd(card->host, card);
                if (err)
                        return err;
        }

        if (is_rpmb) {
                err = mmc_set_blockcount(card, data.blocks,
                        idata->ic.write_flag & (1 << 31));
                if (err)
                        return err;
        }

        if ((MMC_EXTRACT_INDEX_FROM_ARG(cmd.arg) == EXT_CSD_SANITIZE_START) &&
            (cmd.opcode == MMC_SWITCH)) {
                err = ioctl_do_sanitize(card);

                if (err)
                        pr_err("%s: ioctl_do_sanitize() failed. err = %d",
                               __func__, err);

                return err;
        }

        mmc_wait_for_req(card->host, &mrq);

        if (cmd.error) {
                dev_err(mmc_dev(card->host), "%s: cmd error %d\n",
                                                __func__, cmd.error);
                return cmd.error;
        }
        if (data.error) {
                dev_err(mmc_dev(card->host), "%s: data error %d\n",
                                                __func__, data.error);
                return data.error;
        }

        /*
         * According to the SD specs, some commands require a delay after
         * issuing the command.
         */
        if (idata->ic.postsleep_min_us)
                usleep_range(idata->ic.postsleep_min_us, idata->ic.postsleep_max_us);

        memcpy(&(idata->ic.response), cmd.resp, sizeof(cmd.resp));

        if (is_rpmb) {
                /*
                 * Ensure RPMB command has completed by polling CMD13
                 * "Send Status".
                 */
                err = ioctl_rpmb_card_status_poll(card, &status, 5);
                if (err)
                        dev_err(mmc_dev(card->host),
                                        "%s: Card Status=0x%08X, error %d\n",
                                        __func__, status, err);
        }

        return err;
}

static int mmc_blk_ioctl_cmd(struct block_device *bdev,
                             struct mmc_ioc_cmd __user *ic_ptr)
{
        struct mmc_blk_ioc_data *idata;
        struct mmc_blk_ioc_data *idatas[1];
        struct mmc_blk_data *md;
        struct mmc_queue *mq;
        struct mmc_card *card;
        int err = 0, ioc_err = 0;
        struct request *req;

        /*
         * The caller must have CAP_SYS_RAWIO, and must be calling this on the
         * whole block device, not on a partition.  This prevents overspray
         * between sibling partitions.
         */
        if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains))
                return -EPERM;

        idata = mmc_blk_ioctl_copy_from_user(ic_ptr);
        if (IS_ERR(idata))
                return PTR_ERR(idata);

        md = mmc_blk_get(bdev->bd_disk);
        if (!md) {
                err = -EINVAL;
                goto cmd_err;
        }

        card = md->queue.card;
        if (IS_ERR(card)) {
                err = PTR_ERR(card);
                goto cmd_done;
        }

        /*
         * Dispatch the ioctl() into the block request queue.
         */
        mq = &md->queue;
        req = blk_get_request(mq->queue,
                idata->ic.write_flag ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN,
                __GFP_RECLAIM);
        idatas[0] = idata;
        req_to_mmc_queue_req(req)->drv_op = MMC_DRV_OP_IOCTL;
        req_to_mmc_queue_req(req)->idata = idatas;
        req_to_mmc_queue_req(req)->ioc_count = 1;
        blk_execute_rq(mq->queue, NULL, req, 0);
        ioc_err = req_to_mmc_queue_req(req)->drv_op_result;
        err = mmc_blk_ioctl_copy_to_user(ic_ptr, idata);
        blk_put_request(req);

cmd_done:
        mmc_blk_put(md);
cmd_err:
        kfree(idata->buf);
        kfree(idata);
        return ioc_err ? ioc_err : err;
}

static int mmc_blk_ioctl_multi_cmd(struct block_device *bdev,
                                   struct mmc_ioc_multi_cmd __user *user)
{
        struct mmc_blk_ioc_data **idata = NULL;
        struct mmc_ioc_cmd __user *cmds = user->cmds;
        struct mmc_card *card;
        struct mmc_blk_data *md;
        struct mmc_queue *mq;
        int i, err = 0, ioc_err = 0;
        __u64 num_of_cmds;
        struct request *req;

        /*
         * The caller must have CAP_SYS_RAWIO, and must be calling this on the
         * whole block device, not on a partition.  This prevents overspray
         * between sibling partitions.
         */
        if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains))
                return -EPERM;

        if (copy_from_user(&num_of_cmds, &user->num_of_cmds,
                           sizeof(num_of_cmds)))
                return -EFAULT;

        if (!num_of_cmds)
                return 0;

        if (num_of_cmds > MMC_IOC_MAX_CMDS)
                return -EINVAL;

        idata = kcalloc(num_of_cmds, sizeof(*idata), GFP_KERNEL);
        if (!idata)
                return -ENOMEM;

        for (i = 0; i < num_of_cmds; i++) {
                idata[i] = mmc_blk_ioctl_copy_from_user(&cmds[i]);
                if (IS_ERR(idata[i])) {
                        err = PTR_ERR(idata[i]);
                        num_of_cmds = i;
                        goto cmd_err;
                }
        }

        md = mmc_blk_get(bdev->bd_disk);
        if (!md) {
                err = -EINVAL;
                goto cmd_err;
        }

        card = md->queue.card;
        if (IS_ERR(card)) {
                err = PTR_ERR(card);
                goto cmd_done;
        }


        /*
         * Dispatch the ioctl()s into the block request queue.
         */
        mq = &md->queue;
        req = blk_get_request(mq->queue,
                idata[0]->ic.write_flag ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN,
                __GFP_RECLAIM);
        req_to_mmc_queue_req(req)->drv_op = MMC_DRV_OP_IOCTL;
        req_to_mmc_queue_req(req)->idata = idata;
        req_to_mmc_queue_req(req)->ioc_count = num_of_cmds;
        blk_execute_rq(mq->queue, NULL, req, 0);
        ioc_err = req_to_mmc_queue_req(req)->drv_op_result;

        /* copy to user if data and response */
        for (i = 0; i < num_of_cmds && !err; i++)
                err = mmc_blk_ioctl_copy_to_user(&cmds[i], idata[i]);

        blk_put_request(req);

cmd_done:
        mmc_blk_put(md);
cmd_err:
        for (i = 0; i < num_of_cmds; i++) {
                kfree(idata[i]->buf);
                kfree(idata[i]);
        }
        kfree(idata);
        return ioc_err ? ioc_err : err;
}

static int mmc_blk_ioctl(struct block_device *bdev, fmode_t mode,
        unsigned int cmd, unsigned long arg)
{
        switch (cmd) {
        case MMC_IOC_CMD:
                return mmc_blk_ioctl_cmd(bdev,
                                (struct mmc_ioc_cmd __user *)arg);
        case MMC_IOC_MULTI_CMD:
                return mmc_blk_ioctl_multi_cmd(bdev,
                                (struct mmc_ioc_multi_cmd __user *)arg);
        default:
                return -EINVAL;
        }
}

#ifdef CONFIG_COMPAT
static int mmc_blk_compat_ioctl(struct block_device *bdev, fmode_t mode,
        unsigned int cmd, unsigned long arg)
{
        return mmc_blk_ioctl(bdev, mode, cmd, (unsigned long) compat_ptr(arg));
}
#endif

static const struct block_device_operations mmc_bdops = {
        .open                   = mmc_blk_open,
        .release                = mmc_blk_release,
        .getgeo                 = mmc_blk_getgeo,
        .owner                  = THIS_MODULE,
        .ioctl                  = mmc_blk_ioctl,
#ifdef CONFIG_COMPAT
        .compat_ioctl           = mmc_blk_compat_ioctl,
#endif
};

static int mmc_blk_part_switch_pre(struct mmc_card *card,
                                   unsigned int part_type)
{
        int ret = 0;

        if (part_type == EXT_CSD_PART_CONFIG_ACC_RPMB) {
                if (card->ext_csd.cmdq_en) {
                        ret = mmc_cmdq_disable(card);
                        if (ret)
                                return ret;
                }
                mmc_retune_pause(card->host);
        }

        return ret;
}

static int mmc_blk_part_switch_post(struct mmc_card *card,
                                    unsigned int part_type)
{
        int ret = 0;

        if (part_type == EXT_CSD_PART_CONFIG_ACC_RPMB) {
                mmc_retune_unpause(card->host);
                if (card->reenable_cmdq && !card->ext_csd.cmdq_en)
                        ret = mmc_cmdq_enable(card);
        }

        return ret;
}

static inline int mmc_blk_part_switch(struct mmc_card *card,
                                      struct mmc_blk_data *md)
{
        int ret = 0;
        struct mmc_blk_data *main_md = dev_get_drvdata(&card->dev);

        if (main_md->part_curr == md->part_type)
                return 0;

        if (mmc_card_mmc(card)) {
                u8 part_config = card->ext_csd.part_config;

                ret = mmc_blk_part_switch_pre(card, md->part_type);
                if (ret)
                        return ret;

                part_config &= ~EXT_CSD_PART_CONFIG_ACC_MASK;
                part_config |= md->part_type;

                ret = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
                                 EXT_CSD_PART_CONFIG, part_config,
                                 card->ext_csd.part_time);
                if (ret) {
                        mmc_blk_part_switch_post(card, md->part_type);
                        return ret;
                }

                card->ext_csd.part_config = part_config;

                ret = mmc_blk_part_switch_post(card, main_md->part_curr);
        }

        main_md->part_curr = md->part_type;
        return ret;
}

static int mmc_sd_num_wr_blocks(struct mmc_card *card, u32 *written_blocks)
{
        int err;
        u32 result;
        __be32 *blocks;

        struct mmc_request mrq = {};
        struct mmc_command cmd = {};
        struct mmc_data data = {};

        struct scatterlist sg;

        cmd.opcode = MMC_APP_CMD;
        cmd.arg = card->rca << 16;
        cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;

        err = mmc_wait_for_cmd(card->host, &cmd, 0);
        if (err)
                return err;
        if (!mmc_host_is_spi(card->host) && !(cmd.resp[0] & R1_APP_CMD))
                return -EIO;

        memset(&cmd, 0, sizeof(struct mmc_command));

        cmd.opcode = SD_APP_SEND_NUM_WR_BLKS;
        cmd.arg = 0;
        cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;

        data.blksz = 4;
        data.blocks = 1;
        data.flags = MMC_DATA_READ;
        data.sg = &sg;
        data.sg_len = 1;
        mmc_set_data_timeout(&data, card);

        mrq.cmd = &cmd;
        mrq.data = &data;

        blocks = kmalloc(4, GFP_KERNEL);
        if (!blocks)
                return -ENOMEM;

        sg_init_one(&sg, blocks, 4);

        mmc_wait_for_req(card->host, &mrq);

        result = ntohl(*blocks);
        kfree(blocks);

        if (cmd.error || data.error)
                return -EIO;

        *written_blocks = result;

        return 0;
}

static int card_busy_detect(struct mmc_card *card, unsigned int timeout_ms,
                bool hw_busy_detect, struct request *req, bool *gen_err)
{
        unsigned long timeout = jiffies + msecs_to_jiffies(timeout_ms);
        int err = 0;
        u32 status;

        do {
                err = __mmc_send_status(card, &status, 5);
                if (err) {
                        pr_err("%s: error %d requesting status\n",
                               req->rq_disk->disk_name, err);
                        return err;
                }

                if (status & R1_ERROR) {
                        pr_err("%s: %s: error sending status cmd, status %#x\n",
                                req->rq_disk->disk_name, __func__, status);
                        *gen_err = true;
                }

                /* We may rely on the host hw to handle busy detection.*/
                if ((card->host->caps & MMC_CAP_WAIT_WHILE_BUSY) &&
                        hw_busy_detect)
                        break;

                /*
                 * Timeout if the device never becomes ready for data and never
                 * leaves the program state.
                 */
                if (time_after(jiffies, timeout)) {
                        pr_err("%s: Card stuck in programming state! %s %s\n",
                                mmc_hostname(card->host),
                                req->rq_disk->disk_name, __func__);
                        return -ETIMEDOUT;
                }

                /*
                 * Some cards mishandle the status bits,
                 * so make sure to check both the busy
                 * indication and the card state.
                 */
        } while (!(status & R1_READY_FOR_DATA) ||
                 (R1_CURRENT_STATE(status) == R1_STATE_PRG));

        return err;
}

static int send_stop(struct mmc_card *card, unsigned int timeout_ms,
                struct request *req, bool *gen_err, u32 *stop_status)
{
        struct mmc_host *host = card->host;
        struct mmc_command cmd = {};
        int err;
        bool use_r1b_resp = rq_data_dir(req) == WRITE;

        /*
         * Normally we use R1B responses for WRITE, but in cases where the host
         * has specified a max_busy_timeout we need to validate it. A failure
         * means we need to prevent the host from doing hw busy detection, which
         * is done by converting to a R1 response instead.
         */
        if (host->max_busy_timeout && (timeout_ms > host->max_busy_timeout))
                use_r1b_resp = false;

        cmd.opcode = MMC_STOP_TRANSMISSION;
        if (use_r1b_resp) {
                cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
                cmd.busy_timeout = timeout_ms;
        } else {
                cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
        }

        err = mmc_wait_for_cmd(host, &cmd, 5);
        if (err)
                return err;

        *stop_status = cmd.resp[0];

        /* No need to check card status in case of READ. */
        if (rq_data_dir(req) == READ)
                return 0;

        if (!mmc_host_is_spi(host) &&
                (*stop_status & R1_ERROR)) {
                pr_err("%s: %s: general error sending stop command, resp %#x\n",
                        req->rq_disk->disk_name, __func__, *stop_status);
                *gen_err = true;
        }

        return card_busy_detect(card, timeout_ms, use_r1b_resp, req, gen_err);
}

#define ERR_NOMEDIUM    3
#define ERR_RETRY       2
#define ERR_ABORT       1
#define ERR_CONTINUE    0

static int mmc_blk_cmd_error(struct request *req, const char *name, int error,
        bool status_valid, u32 status)
{
        switch (error) {
        case -EILSEQ:
                /* response crc error, retry the r/w cmd */
                pr_err("%s: %s sending %s command, card status %#x\n",
                        req->rq_disk->disk_name, "response CRC error",
                        name, status);
                return ERR_RETRY;

        case -ETIMEDOUT:
                pr_err("%s: %s sending %s command, card status %#x\n",
                        req->rq_disk->disk_name, "timed out", name, status);

                /* If the status cmd initially failed, retry the r/w cmd */
                if (!status_valid) {
                        pr_err("%s: status not valid, retrying timeout\n",
                                req->rq_disk->disk_name);
                        return ERR_RETRY;
                }

                /*
                 * If it was a r/w cmd crc error, or illegal command
                 * (eg, issued in wrong state) then retry - we should
                 * have corrected the state problem above.
                 */
                if (status & (R1_COM_CRC_ERROR | R1_ILLEGAL_COMMAND)) {
                        pr_err("%s: command error, retrying timeout\n",
                                req->rq_disk->disk_name);
                        return ERR_RETRY;
                }

                /* Otherwise abort the command */
                return ERR_ABORT;

        default:
                /* We don't understand the error code the driver gave us */
                pr_err("%s: unknown error %d sending read/write command, card status %#x\n",
                       req->rq_disk->disk_name, error, status);
                return ERR_ABORT;
        }
}

/*
 * Initial r/w and stop cmd error recovery.
 * We don't know whether the card received the r/w cmd or not, so try to
 * restore things back to a sane state.  Essentially, we do this as follows:
 * - Obtain card status.  If the first attempt to obtain card status fails,
 *   the status word will reflect the failed status cmd, not the failed
 *   r/w cmd.  If we fail to obtain card status, it suggests we can no
 *   longer communicate with the card.
 * - Check the card state.  If the card received the cmd but there was a
 *   transient problem with the response, it might still be in a data transfer
 *   mode.  Try to send it a stop command.  If this fails, we can't recover.
 * - If the r/w cmd failed due to a response CRC error, it was probably
 *   transient, so retry the cmd.
 * - If the r/w cmd timed out, but we didn't get the r/w cmd status, retry.
 * - If the r/w cmd timed out, and the r/w cmd failed due to CRC error or
 *   illegal cmd, retry.
 * Otherwise we don't understand what happened, so abort.
 */
static int mmc_blk_cmd_recovery(struct mmc_card *card, struct request *req,
        struct mmc_blk_request *brq, bool *ecc_err, bool *gen_err)
{
        bool prev_cmd_status_valid = true;
        u32 status, stop_status = 0;
        int err, retry;

        if (mmc_card_removed(card))
                return ERR_NOMEDIUM;

        /*
         * Try to get card status which indicates both the card state
         * and why there was no response.  If the first attempt fails,
         * we can't be sure the returned status is for the r/w command.
         */
        for (retry = 2; retry >= 0; retry--) {
                err = __mmc_send_status(card, &status, 0);
                if (!err)
                        break;

                /* Re-tune if needed */
                mmc_retune_recheck(card->host);

                prev_cmd_status_valid = false;
                pr_err("%s: error %d sending status command, %sing\n",
                       req->rq_disk->disk_name, err, retry ? "retry" : "abort");
        }

        /* We couldn't get a response from the card.  Give up. */
        if (err) {
                /* Check if the card is removed */
                if (mmc_detect_card_removed(card->host))
                        return ERR_NOMEDIUM;
                return ERR_ABORT;
        }

        /* Flag ECC errors */
        if ((status & R1_CARD_ECC_FAILED) ||
            (brq->stop.resp[0] & R1_CARD_ECC_FAILED) ||
            (brq->cmd.resp[0] & R1_CARD_ECC_FAILED))
                *ecc_err = true;

        /* Flag General errors */
        if (!mmc_host_is_spi(card->host) && rq_data_dir(req) != READ)
                if ((status & R1_ERROR) ||
                        (brq->stop.resp[0] & R1_ERROR)) {
                        pr_err("%s: %s: general error sending stop or status command, stop cmd response %#x, card status %#x\n",
                               req->rq_disk->disk_name, __func__,
                               brq->stop.resp[0], status);
                        *gen_err = true;
                }

        /*
         * Check the current card state.  If it is in some data transfer
         * mode, tell it to stop (and hopefully transition back to TRAN.)
         */
        if (R1_CURRENT_STATE(status) == R1_STATE_DATA ||
            R1_CURRENT_STATE(status) == R1_STATE_RCV) {
                err = send_stop(card,
                        DIV_ROUND_UP(brq->data.timeout_ns, 1000000),
                        req, gen_err, &stop_status);
                if (err) {
                        pr_err("%s: error %d sending stop command\n",
                               req->rq_disk->disk_name, err);
                        /*
                         * If the stop cmd also timed out, the card is probably
                         * not present, so abort. Other errors are bad news too.
                         */
                        return ERR_ABORT;
                }

                if (stop_status & R1_CARD_ECC_FAILED)
                        *ecc_err = true;
        }

        /* Check for set block count errors */
        if (brq->sbc.error)
                return mmc_blk_cmd_error(req, "SET_BLOCK_COUNT", brq->sbc.error,
                                prev_cmd_status_valid, status);

        /* Check for r/w command errors */
        if (brq->cmd.error)
                return mmc_blk_cmd_error(req, "r/w cmd", brq->cmd.error,
                                prev_cmd_status_valid, status);

        /* Data errors */
        if (!brq->stop.error)
                return ERR_CONTINUE;

        /* Now for stop errors.  These aren't fatal to the transfer. */
        pr_info("%s: error %d sending stop command, original cmd response %#x, card status %#x\n",
               req->rq_disk->disk_name, brq->stop.error,
               brq->cmd.resp[0], status);

        /*
         * Subsitute in our own stop status as this will give the error
         * state which happened during the execution of the r/w command.
         */
        if (stop_status) {
                brq->stop.resp[0] = stop_status;
                brq->stop.error = 0;
        }
        return ERR_CONTINUE;
}

static int mmc_blk_reset(struct mmc_blk_data *md, struct mmc_host *host,
                         int type)
{
        int err;

        if (md->reset_done & type)
                return -EEXIST;

        md->reset_done |= type;
        err = mmc_hw_reset(host);
        /* Ensure we switch back to the correct partition */
        if (err != -EOPNOTSUPP) {
                struct mmc_blk_data *main_md =
                        dev_get_drvdata(&host->card->dev);
                int part_err;

                main_md->part_curr = main_md->part_type;
                part_err = mmc_blk_part_switch(host->card, md);
                if (part_err) {
                        /*
                         * We have failed to get back into the correct
                         * partition, so we need to abort the whole request.
                         */
                        return -ENODEV;
                }
        }
        return err;
}

static inline void mmc_blk_reset_success(struct mmc_blk_data *md, int type)
{
        md->reset_done &= ~type;
}

int mmc_access_rpmb(struct mmc_queue *mq)
{
        struct mmc_blk_data *md = mq->blkdata;
        /*
         * If this is a RPMB partition access, return ture
         */
        if (md && md->part_type == EXT_CSD_PART_CONFIG_ACC_RPMB)
                return true;

        return false;
}

/*
 * The non-block commands come back from the block layer after it queued it and
 * processed it with all other requests and then they get issued in this
 * function.
 */
static void mmc_blk_issue_drv_op(struct mmc_queue *mq, struct request *req)
{
        struct mmc_queue_req *mq_rq;
        struct mmc_card *card = mq->card;
        struct mmc_blk_data *md = mq->blkdata;
        int ret;
        int i;

        mq_rq = req_to_mmc_queue_req(req);

        switch (mq_rq->drv_op) {
        case MMC_DRV_OP_IOCTL:
                for (i = 0, ret = 0; i < mq_rq->ioc_count; i++) {
                        ret = __mmc_blk_ioctl_cmd(card, md, mq_rq->idata[i]);
                        if (ret)
                                break;
                }
                /* Always switch back to main area after RPMB access */
                if (md->area_type & MMC_BLK_DATA_AREA_RPMB)
                        mmc_blk_part_switch(card, dev_get_drvdata(&card->dev));
                break;
        case MMC_DRV_OP_BOOT_WP:
                ret = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_BOOT_WP,
                                 card->ext_csd.boot_ro_lock |
                                 EXT_CSD_BOOT_WP_B_PWR_WP_EN,
                                 card->ext_csd.part_time);
                if (ret)
                        pr_err("%s: Locking boot partition ro until next power on failed: %d\n",
                               md->disk->disk_name, ret);
                else
                        card->ext_csd.boot_ro_lock |=
                                EXT_CSD_BOOT_WP_B_PWR_WP_EN;
                break;
        default:
                pr_err("%s: unknown driver specific operation\n",
                       md->disk->disk_name);
                ret = -EINVAL;
                break;
        }
        mq_rq->drv_op_result = ret;
        blk_end_request_all(req, ret ? BLK_STS_IOERR : BLK_STS_OK);
}

static void mmc_blk_issue_discard_rq(struct mmc_queue *mq, struct request *req)
{
        struct mmc_blk_data *md = mq->blkdata;
        struct mmc_card *card = md->queue.card;
        unsigned int from, nr, arg;
        int err = 0, type = MMC_BLK_DISCARD;
        blk_status_t status = BLK_STS_OK;

        if (!mmc_can_erase(card)) {
                status = BLK_STS_NOTSUPP;
                goto fail;
        }

        from = blk_rq_pos(req);
        nr = blk_rq_sectors(req);

        if (mmc_can_discard(card))
                arg = MMC_DISCARD_ARG;
        else if (mmc_can_trim(card))
                arg = MMC_TRIM_ARG;
        else
                arg = MMC_ERASE_ARG;
        do {
                err = 0;
                if (card->quirks & MMC_QUIRK_INAND_CMD38) {
                        err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
                                         INAND_CMD38_ARG_EXT_CSD,
                                         arg == MMC_TRIM_ARG ?
                                         INAND_CMD38_ARG_TRIM :
                                         INAND_CMD38_ARG_ERASE,
                                         0);
                }
                if (!err)
                        err = mmc_erase(card, from, nr, arg);
        } while (err == -EIO && !mmc_blk_reset(md, card->host, type));
        if (err)
                status = BLK_STS_IOERR;
        else
                mmc_blk_reset_success(md, type);
fail:
        blk_end_request(req, status, blk_rq_bytes(req));
}

static void mmc_blk_issue_secdiscard_rq(struct mmc_queue *mq,
                                       struct request *req)
{
        struct mmc_blk_data *md = mq->blkdata;
        struct mmc_card *card = md->queue.card;
        unsigned int from, nr, arg;
        int err = 0, type = MMC_BLK_SECDISCARD;
        blk_status_t status = BLK_STS_OK;

        if (!(mmc_can_secure_erase_trim(card))) {
                status = BLK_STS_NOTSUPP;
                goto out;
        }

        from = blk_rq_pos(req);
        nr = blk_rq_sectors(req);

        if (mmc_can_trim(card) && !mmc_erase_group_aligned(card, from, nr))
                arg = MMC_SECURE_TRIM1_ARG;
        else
                arg = MMC_SECURE_ERASE_ARG;

retry:
        if (card->quirks & MMC_QUIRK_INAND_CMD38) {
                err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
                                 INAND_CMD38_ARG_EXT_CSD,
                                 arg == MMC_SECURE_TRIM1_ARG ?
                                 INAND_CMD38_ARG_SECTRIM1 :
                                 INAND_CMD38_ARG_SECERASE,
                                 0);
                if (err)
                        goto out_retry;
        }

        err = mmc_erase(card, from, nr, arg);
        if (err == -EIO)
                goto out_retry;
        if (err) {
                status = BLK_STS_IOERR;
                goto out;
        }

        if (arg == MMC_SECURE_TRIM1_ARG) {
                if (card->quirks & MMC_QUIRK_INAND_CMD38) {
                        err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
                                         INAND_CMD38_ARG_EXT_CSD,
                                         INAND_CMD38_ARG_SECTRIM2,
                                         0);
                        if (err)
                                goto out_retry;
                }

                err = mmc_erase(card, from, nr, MMC_SECURE_TRIM2_ARG);
                if (err == -EIO)
                        goto out_retry;
                if (err) {
                        status = BLK_STS_IOERR;
                        goto out;
                }
        }

out_retry:
        if (err && !mmc_blk_reset(md, card->host, type))
                goto retry;
        if (!err)
                mmc_blk_reset_success(md, type);
out:
        blk_end_request(req, status, blk_rq_bytes(req));
}

static void mmc_blk_issue_flush(struct mmc_queue *mq, struct request *req)
{
        struct mmc_blk_data *md = mq->blkdata;
        struct mmc_card *card = md->queue.card;
        int ret = 0;

        ret = mmc_flush_cache(card);
        blk_end_request_all(req, ret ? BLK_STS_IOERR : BLK_STS_OK);
}

/*
 * Reformat current write as a reliable write, supporting
 * both legacy and the enhanced reliable write MMC cards.
 * In each transfer we'll handle only as much as a single
 * reliable write can handle, thus finish the request in
 * partial completions.
 */
static inline void mmc_apply_rel_rw(struct mmc_blk_request *brq,
                                    struct mmc_card *card,
                                    struct request *req)
{
        if (!(card->ext_csd.rel_param & EXT_CSD_WR_REL_PARAM_EN)) {
                /* Legacy mode imposes restrictions on transfers. */
                if (!IS_ALIGNED(blk_rq_pos(req), card->ext_csd.rel_sectors))
                        brq->data.blocks = 1;

                if (brq->data.blocks > card->ext_csd.rel_sectors)
                        brq->data.blocks = card->ext_csd.rel_sectors;
                else if (brq->data.blocks < card->ext_csd.rel_sectors)
                        brq->data.blocks = 1;
        }
}

#define CMD_ERRORS                                                      \
        (R1_OUT_OF_RANGE |      /* Command argument out of range */     \
         R1_ADDRESS_ERROR |     /* Misaligned address */                \
         R1_BLOCK_LEN_ERROR |   /* Transferred block length incorrect */\
         R1_WP_VIOLATION |      /* Tried to write to protected block */ \
         R1_CARD_ECC_FAILED |   /* Card ECC failed */                   \
         R1_CC_ERROR |          /* Card controller error */             \
         R1_ERROR)              /* General/unknown error */

static void mmc_blk_eval_resp_error(struct mmc_blk_request *brq)
{
        u32 val;

        /*
         * Per the SD specification(physical layer version 4.10)[1],
         * section 4.3.3, it explicitly states that "When the last
         * block of user area is read using CMD18, the host should
         * ignore OUT_OF_RANGE error that may occur even the sequence
         * is correct". And JESD84-B51 for eMMC also has a similar
         * statement on section 6.8.3.
         *
         * Multiple block read/write could be done by either predefined
         * method, namely CMD23, or open-ending mode. For open-ending mode,
         * we should ignore the OUT_OF_RANGE error as it's normal behaviour.
         *
         * However the spec[1] doesn't tell us whether we should also
         * ignore that for predefined method. But per the spec[1], section
         * 4.15 Set Block Count Command, it says"If illegal block count
         * is set, out of range error will be indicated during read/write
         * operation (For example, data transfer is stopped at user area
         * boundary)." In another word, we could expect a out of range error
         * in the response for the following CMD18/25. And if argument of
         * CMD23 + the argument of CMD18/25 exceed the max number of blocks,
         * we could also expect to get a -ETIMEDOUT or any error number from
         * the host drivers due to missing data response(for write)/data(for
         * read), as the cards will stop the data transfer by itself per the
         * spec. So we only need to check R1_OUT_OF_RANGE for open-ending mode.
         */

        if (!brq->stop.error) {
                bool oor_with_open_end;
                /* If there is no error yet, check R1 response */

                val = brq->stop.resp[0] & CMD_ERRORS;
                oor_with_open_end = val & R1_OUT_OF_RANGE && !brq->mrq.sbc;

                if (val && !oor_with_open_end)
                        brq->stop.error = -EIO;
        }
}

static enum mmc_blk_status mmc_blk_err_check(struct mmc_card *card,
                                             struct mmc_async_req *areq)
{
        struct mmc_queue_req *mq_mrq = container_of(areq, struct mmc_queue_req,
                                                    areq);
        struct mmc_blk_request *brq = &mq_mrq->brq;
        struct request *req = mmc_queue_req_to_req(mq_mrq);
        int need_retune = card->host->need_retune;
        bool ecc_err = false;
        bool gen_err = false;

        /*
         * sbc.error indicates a problem with the set block count
         * command.  No data will have been transferred.
         *
         * cmd.error indicates a problem with the r/w command.  No
         * data will have been transferred.
         *
         * stop.error indicates a problem with the stop command.  Data
         * may have been transferred, or may still be transferring.
         */

        mmc_blk_eval_resp_error(brq);

        if (brq->sbc.error || brq->cmd.error ||
            brq->stop.error || brq->data.error) {
                switch (mmc_blk_cmd_recovery(card, req, brq, &ecc_err, &gen_err)) {
                case ERR_RETRY:
                        return MMC_BLK_RETRY;
                case ERR_ABORT:
                        return MMC_BLK_ABORT;
                case ERR_NOMEDIUM:
                        return MMC_BLK_NOMEDIUM;
                case ERR_CONTINUE:
                        break;
                }
        }

        /*
         * Check for errors relating to the execution of the
         * initial command - such as address errors.  No data
         * has been transferred.
         */
        if (brq->cmd.resp[0] & CMD_ERRORS) {
                pr_err("%s: r/w command failed, status = %#x\n",
                       req->rq_disk->disk_name, brq->cmd.resp[0]);
                return MMC_BLK_ABORT;
        }

        /*
         * Everything else is either success, or a data error of some
         * kind.  If it was a write, we may have transitioned to
         * program mode, which we have to wait for it to complete.
         */
        if (!mmc_host_is_spi(card->host) && rq_data_dir(req) != READ) {
                int err;

                /* Check stop command response */
                if (brq->stop.resp[0] & R1_ERROR) {
                        pr_err("%s: %s: general error sending stop command, stop cmd response %#x\n",
                               req->rq_disk->disk_name, __func__,
                               brq->stop.resp[0]);
                        gen_err = true;
                }

                err = card_busy_detect(card, MMC_BLK_TIMEOUT_MS, false, req,
                                        &gen_err);
                if (err)
                        return MMC_BLK_CMD_ERR;
        }

        /* if general error occurs, retry the write operation. */
        if (gen_err) {
                pr_warn("%s: retrying write for general error\n",
                                req->rq_disk->disk_name);
                return MMC_BLK_RETRY;
        }

        /* Some errors (ECC) are flagged on the next commmand, so check stop, too */
        if (brq->data.error || brq->stop.error) {
                if (need_retune && !brq->retune_retry_done) {
                        pr_debug("%s: retrying because a re-tune was needed\n",
                                 req->rq_disk->disk_name);
                        brq->retune_retry_done = 1;
                        return MMC_BLK_RETRY;
                }
                pr_err("%s: error %d transferring data, sector %u, nr %u, cmd response %#x, card status %#x\n",
                       req->rq_disk->disk_name, brq->data.error ?: brq->stop.error,
                       (unsigned)blk_rq_pos(req),
                       (unsigned)blk_rq_sectors(req),
                       brq->cmd.resp[0], brq->stop.resp[0]);

                if (rq_data_dir(req) == READ) {
                        if (ecc_err)
                                return MMC_BLK_ECC_ERR;
                        return MMC_BLK_DATA_ERR;
                } else {
                        return MMC_BLK_CMD_ERR;
                }
        }

        if (!brq->data.bytes_xfered)
                return MMC_BLK_RETRY;

        if (blk_rq_bytes(req) != brq->data.bytes_xfered)
                return MMC_BLK_PARTIAL;

        return MMC_BLK_SUCCESS;
}

static void mmc_blk_data_prep(struct mmc_queue *mq, struct mmc_queue_req *mqrq,
                              int disable_multi, bool *do_rel_wr,
                              bool *do_data_tag)
{
        struct mmc_blk_data *md = mq->blkdata;
        struct mmc_card *card = md->queue.card;
        struct mmc_blk_request *brq = &mqrq->brq;
        struct request *req = mmc_queue_req_to_req(mqrq);

        /*
         * Reliable writes are used to implement Forced Unit Access and
         * are supported only on MMCs.
         */
        *do_rel_wr = (req->cmd_flags & REQ_FUA) &&
                     rq_data_dir(req) == WRITE &&
                     (md->flags & MMC_BLK_REL_WR);

        memset(brq, 0, sizeof(struct mmc_blk_request));

        brq->mrq.data = &brq->data;

        brq->stop.opcode = MMC_STOP_TRANSMISSION;
        brq->stop.arg = 0;

        if (rq_data_dir(req) == READ) {
                brq->data.flags = MMC_DATA_READ;
                brq->stop.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
        } else {
                brq->data.flags = MMC_DATA_WRITE;
                brq->stop.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
        }

        brq->data.blksz = 512;
        brq->data.blocks = blk_rq_sectors(req);

        /*
         * The block layer doesn't support all sector count
         * restrictions, so we need to be prepared for too big
         * requests.
         */
        if (brq->data.blocks > card->host->max_blk_count)
                brq->data.blocks = card->host->max_blk_count;

        if (brq->data.blocks > 1) {
                /*
                 * After a read error, we redo the request one sector
                 * at a time in order to accurately determine which
                 * sectors can be read successfully.
                 */
                if (disable_multi)
                        brq->data.blocks = 1;

                /*
                 * Some controllers have HW issues while operating
                 * in multiple I/O mode
                 */
                if (card->host->ops->multi_io_quirk)
                        brq->data.blocks = card->host->ops->multi_io_quirk(card,
                                                (rq_data_dir(req) == READ) ?
                                                MMC_DATA_READ : MMC_DATA_WRITE,
                                                brq->data.blocks);
        }

        if (*do_rel_wr)
                mmc_apply_rel_rw(brq, card, req);

        /*
         * Data tag is used only during writing meta data to speed
         * up write and any subsequent read of this meta data
         */
        *do_data_tag = card->ext_csd.data_tag_unit_size &&
                       (req->cmd_flags & REQ_META) &&
                       (rq_data_dir(req) == WRITE) &&
                       ((brq->data.blocks * brq->data.blksz) >=
                        card->ext_csd.data_tag_unit_size);

        mmc_set_data_timeout(&brq->data, card);

        brq->data.sg = mqrq->sg;
        brq->data.sg_len = mmc_queue_map_sg(mq, mqrq);

        /*
         * Adjust the sg list so it is the same size as the
         * request.
         */
        if (brq->data.blocks != blk_rq_sectors(req)) {
                int i, data_size = brq->data.blocks << 9;
                struct scatterlist *sg;

                for_each_sg(brq->data.sg, sg, brq->data.sg_len, i) {
                        data_size -= sg->length;
                        if (data_size <= 0) {
                                sg->length += data_size;
                                i++;
                                break;
                        }
                }
                brq->data.sg_len = i;
        }

        mqrq->areq.mrq = &brq->mrq;

        mmc_queue_bounce_pre(mqrq);
}

static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq,
                               struct mmc_card *card,
                               int disable_multi,
                               struct mmc_queue *mq)
{
        u32 readcmd, writecmd;
        struct mmc_blk_request *brq = &mqrq->brq;
        struct request *req = mmc_queue_req_to_req(mqrq);
        struct mmc_blk_data *md = mq->blkdata;
        bool do_rel_wr, do_data_tag;

        mmc_blk_data_prep(mq, mqrq, disable_multi, &do_rel_wr, &do_data_tag);

        brq->mrq.cmd = &brq->cmd;

        brq->cmd.arg = blk_rq_pos(req);
        if (!mmc_card_blockaddr(card))
                brq->cmd.arg <<= 9;
        brq->cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;

        if (brq->data.blocks > 1 || do_rel_wr) {
                /* SPI multiblock writes terminate using a special
                 * token, not a STOP_TRANSMISSION request.
                 */
                if (!mmc_host_is_spi(card->host) ||
                    rq_data_dir(req) == READ)
                        brq->mrq.stop = &brq->stop;
                readcmd = MMC_READ_MULTIPLE_BLOCK;
                writecmd = MMC_WRITE_MULTIPLE_BLOCK;
        } else {
                brq->mrq.stop = NULL;
                readcmd = MMC_READ_SINGLE_BLOCK;
                writecmd = MMC_WRITE_BLOCK;
        }
        brq->cmd.opcode = rq_data_dir(req) == READ ? readcmd : writecmd;

        /*
         * Pre-defined multi-block transfers are preferable to
         * open ended-ones (and necessary for reliable writes).
         * However, it is not sufficient to just send CMD23,
         * and avoid the final CMD12, as on an error condition
         * CMD12 (stop) needs to be sent anyway. This, coupled
         * with Auto-CMD23 enhancements provided by some
         * hosts, means that the complexity of dealing
         * with this is best left to the host. If CMD23 is
         * supported by card and host, we'll fill sbc in and let
         * the host deal with handling it correctly. This means
         * that for hosts that don't expose MMC_CAP_CMD23, no
         * change of behavior will be observed.
         *
         * N.B: Some MMC cards experience perf degradation.
         * We'll avoid using CMD23-bounded multiblock writes for
         * these, while retaining features like reliable writes.
         */
        if ((md->flags & MMC_BLK_CMD23) && mmc_op_multi(brq->cmd.opcode) &&
            (do_rel_wr || !(card->quirks & MMC_QUIRK_BLK_NO_CMD23) ||
             do_data_tag)) {
                brq->sbc.opcode = MMC_SET_BLOCK_COUNT;
                brq->sbc.arg = brq->data.blocks |
                        (do_rel_wr ? (1 << 31) : 0) |
                        (do_data_tag ? (1 << 29) : 0);
                brq->sbc.flags = MMC_RSP_R1 | MMC_CMD_AC;
                brq->mrq.sbc = &brq->sbc;
        }

        mqrq->areq.err_check = mmc_blk_err_check;
}

static bool mmc_blk_rw_cmd_err(struct mmc_blk_data *md, struct mmc_card *card,
                               struct mmc_blk_request *brq, struct request *req,
                               bool old_req_pending)
{
        bool req_pending;

        /*
         * If this is an SD card and we're writing, we can first
         * mark the known good sectors as ok.
         *
         * If the card is not SD, we can still ok written sectors
         * as reported by the controller (which might be less than
         * the real number of written sectors, but never more).
         */
        if (mmc_card_sd(card)) {
                u32 blocks;
                int err;

                err = mmc_sd_num_wr_blocks(card, &blocks);
                if (err)
                        req_pending = old_req_pending;
                else
                        req_pending = blk_end_request(req, BLK_STS_OK, blocks << 9);
        } else {
                req_pending = blk_end_request(req, BLK_STS_OK, brq->data.bytes_xfered);
        }
        return req_pending;
}

static void mmc_blk_rw_cmd_abort(struct mmc_queue *mq, struct mmc_card *card,
                                 struct request *req,
                                 struct mmc_queue_req *mqrq)
{
        if (mmc_card_removed(card))
                req->rq_flags |= RQF_QUIET;
        while (blk_end_request(req, BLK_STS_IOERR, blk_rq_cur_bytes(req)));
        mq->qcnt--;
}

/**
 * mmc_blk_rw_try_restart() - tries to restart the current async request
 * @mq: the queue with the card and host to restart
 * @req: a new request that want to be started after the current one
 */
static void mmc_blk_rw_try_restart(struct mmc_queue *mq, struct request *req,
                                   struct mmc_queue_req *mqrq)
{
        if (!req)
                return;

        /*
         * If the card was removed, just cancel everything and return.
         */
        if (mmc_card_removed(mq->card)) {
                req->rq_flags |= RQF_QUIET;
                blk_end_request_all(req, BLK_STS_IOERR);
                mq->qcnt--; /* FIXME: just set to 0? */
                return;
        }
        /* Else proceed and try to restart the current async request */
        mmc_blk_rw_rq_prep(mqrq, mq->card, 0, mq);
        mmc_start_areq(mq->card->host, &mqrq->areq, NULL);
}

static void mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *new_req)
{
        struct mmc_blk_data *md = mq->blkdata;
        struct mmc_card *card = md->queue.card;
        struct mmc_blk_request *brq;
        int disable_multi = 0, retry = 0, type, retune_retry_done = 0;
        enum mmc_blk_status status;
        struct mmc_queue_req *mqrq_cur = NULL;
        struct mmc_queue_req *mq_rq;
        struct request *old_req;
        struct mmc_async_req *new_areq;
        struct mmc_async_req *old_areq;
        bool req_pending = true;

        if (new_req) {
                mqrq_cur = req_to_mmc_queue_req(new_req);
                mq->qcnt++;
        }

        if (!mq->qcnt)
                return;

        do {
                if (new_req) {
                        /*
                         * When 4KB native sector is enabled, only 8 blocks
                         * multiple read or write is allowed
                         */
                        if (mmc_large_sector(card) &&
                                !IS_ALIGNED(blk_rq_sectors(new_req), 8)) {
                                pr_err("%s: Transfer size is not 4KB sector size aligned\n",
                                        new_req->rq_disk->disk_name);
                                mmc_blk_rw_cmd_abort(mq, card, new_req, mqrq_cur);
                                return;
                        }

                        mmc_blk_rw_rq_prep(mqrq_cur, card, 0, mq);
                        new_areq = &mqrq_cur->areq;
                } else
                        new_areq = NULL;

                old_areq = mmc_start_areq(card->host, new_areq, &status);
                if (!old_areq) {
                        /*
                         * We have just put the first request into the pipeline
                         * and there is nothing more to do until it is
                         * complete.
                         */
                        return;
                }

                /*
                 * An asynchronous request has been completed and we proceed
                 * to handle the result of it.
                 */
                mq_rq = container_of(old_areq, struct mmc_queue_req, areq);
                brq = &mq_rq->brq;
                old_req = mmc_queue_req_to_req(mq_rq);
                type = rq_data_dir(old_req) == READ ? MMC_BLK_READ : MMC_BLK_WRITE;
                mmc_queue_bounce_post(mq_rq);

                switch (status) {
                case MMC_BLK_SUCCESS:
                case MMC_BLK_PARTIAL:
                        /*
                         * A block was successfully transferred.
                         */
                        mmc_blk_reset_success(md, type);

                        req_pending = blk_end_request(old_req, BLK_STS_OK,
                                                      brq->data.bytes_xfered);
                        /*
                         * If the blk_end_request function returns non-zero even
                         * though all data has been transferred and no errors
                         * were returned by the host controller, it's a bug.
                         */
                        if (status == MMC_BLK_SUCCESS && req_pending) {
                                pr_err("%s BUG rq_tot %d d_xfer %d\n",
                                       __func__, blk_rq_bytes(old_req),
                                       brq->data.bytes_xfered);
                                mmc_blk_rw_cmd_abort(mq, card, old_req, mq_rq);
                                return;
                        }
                        break;
                case MMC_BLK_CMD_ERR:
                        req_pending = mmc_blk_rw_cmd_err(md, card, brq, old_req, req_pending);
                        if (mmc_blk_reset(md, card->host, type)) {
                                if (req_pending)
                                        mmc_blk_rw_cmd_abort(mq, card, old_req, mq_rq);
                                else
                                        mq->qcnt--;
                                mmc_blk_rw_try_restart(mq, new_req, mqrq_cur);
                                return;
                        }
                        if (!req_pending) {
                                mq->qcnt--;
                                mmc_blk_rw_try_restart(mq, new_req, mqrq_cur);
                                return;
                        }
                        break;
                case MMC_BLK_RETRY:
                        retune_retry_done = brq->retune_retry_done;
                        if (retry++ < 5)
                                break;
                        /* Fall through */
                case MMC_BLK_ABORT:
                        if (!mmc_blk_reset(md, card->host, type))
                                break;
                        mmc_blk_rw_cmd_abort(mq, card, old_req, mq_rq);
                        mmc_blk_rw_try_restart(mq, new_req, mqrq_cur);
                        return;
                case MMC_BLK_DATA_ERR: {
                        int err;

                        err = mmc_blk_reset(md, card->host, type);
                        if (!err)
                                break;
                        if (err == -ENODEV) {
                                mmc_blk_rw_cmd_abort(mq, card, old_req, mq_rq);
                                mmc_blk_rw_try_restart(mq, new_req, mqrq_cur);
                                return;
                        }
                        /* Fall through */
                }
                case MMC_BLK_ECC_ERR:
                        if (brq->data.blocks > 1) {
                                /* Redo read one sector at a time */
                                pr_warn("%s: retrying using single block read\n",
                                        old_req->rq_disk->disk_name);
                                disable_multi = 1;
                                break;
                        }
                        /*
                         * After an error, we redo I/O one sector at a
                         * time, so we only reach here after trying to
                         * read a single sector.
                         */
                        req_pending = blk_end_request(old_req, BLK_STS_IOERR,
                                                      brq->data.blksz);
                        if (!req_pending) {
                                mq->qcnt--;
                                mmc_blk_rw_try_restart(mq, new_req, mqrq_cur);
                                return;
                        }
                        break;
                case MMC_BLK_NOMEDIUM:
                        mmc_blk_rw_cmd_abort(mq, card, old_req, mq_rq);
                        mmc_blk_rw_try_restart(mq, new_req, mqrq_cur);
                        return;
                default:
                        pr_err("%s: Unhandled return value (%d)",
                                        old_req->rq_disk->disk_name, status);
                        mmc_blk_rw_cmd_abort(mq, card, old_req, mq_rq);
                        mmc_blk_rw_try_restart(mq, new_req, mqrq_cur);
                        return;
                }

                if (req_pending) {
                        /*
                         * In case of a incomplete request
                         * prepare it again and resend.
                         */
                        mmc_blk_rw_rq_prep(mq_rq, card,
                                        disable_multi, mq);
                        mmc_start_areq(card->host,
                                        &mq_rq->areq, NULL);
                        mq_rq->brq.retune_retry_done = retune_retry_done;
                }
        } while (req_pending);

        mq->qcnt--;
}

void mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
{
        int ret;
        struct mmc_blk_data *md = mq->blkdata;
        struct mmc_card *card = md->queue.card;

        if (req && !mq->qcnt)
                /* claim host only for the first request */
                mmc_get_card(card);

        ret = mmc_blk_part_switch(card, md);
        if (ret) {
                if (req) {
                        blk_end_request_all(req, BLK_STS_IOERR);
                }
                goto out;
        }

        if (req) {
                switch (req_op(req)) {
                case REQ_OP_DRV_IN:
                case REQ_OP_DRV_OUT:
                        /*
                         * Complete ongoing async transfer before issuing
                         * ioctl()s
                         */
                        if (mq->qcnt)
                                mmc_blk_issue_rw_rq(mq, NULL);
                        mmc_blk_issue_drv_op(mq, req);
                        break;
                case REQ_OP_DISCARD:
                        /*
                         * Complete ongoing async transfer before issuing
                         * discard.
                         */
                        if (mq->qcnt)
                                mmc_blk_issue_rw_rq(mq, NULL);
                        mmc_blk_issue_discard_rq(mq, req);
                        break;
                case REQ_OP_SECURE_ERASE:
                        /*
                         * Complete ongoing async transfer before issuing
                         * secure erase.
                         */
                        if (mq->qcnt)
                                mmc_blk_issue_rw_rq(mq, NULL);
                        mmc_blk_issue_secdiscard_rq(mq, req);
                        break;
                case REQ_OP_FLUSH:
                        /*
                         * Complete ongoing async transfer before issuing
                         * flush.
                         */
                        if (mq->qcnt)
                                mmc_blk_issue_rw_rq(mq, NULL);
                        mmc_blk_issue_flush(mq, req);
                        break;
                default:
                        /* Normal request, just issue it */
                        mmc_blk_issue_rw_rq(mq, req);
                        card->host->context_info.is_waiting_last_req = false;
                        break;
                }
        } else {
                /* No request, flushing the pipeline with NULL */

                mmc_blk_issue_rw_rq(mq, NULL);
                card->host->context_info.is_waiting_last_req = false;
        }

out:
        if (!mq->qcnt)
                mmc_put_card(card);
}

static inline int mmc_blk_readonly(struct mmc_card *card)
{
        return mmc_card_readonly(card) ||
               !(card->csd.cmdclass & CCC_BLOCK_WRITE);
}

static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card,
                                              struct device *parent,
                                              sector_t size,
                                              bool default_ro,
                                              const char *subname,
                                              int area_type)
{
        struct mmc_blk_data *md;
        int devidx, ret;

        devidx = ida_simple_get(&mmc_blk_ida, 0, max_devices, GFP_KERNEL);
        if (devidx < 0)
                return ERR_PTR(devidx);

        md = kzalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
        if (!md) {
                ret = -ENOMEM;
                goto out;
        }

        md->area_type = area_type;

        /*
         * Set the read-only status based on the supported commands
         * and the write protect switch.
         */
        md->read_only = mmc_blk_readonly(card);

        md->disk = alloc_disk(perdev_minors);
        if (md->disk == NULL) {
                ret = -ENOMEM;
                goto err_kfree;
        }

        spin_lock_init(&md->lock);
        INIT_LIST_HEAD(&md->part);
        md->usage = 1;

        ret = mmc_init_queue(&md->queue, card, &md->lock, subname);
        if (ret)
                goto err_putdisk;

        md->queue.blkdata = md;

        md->disk->major = MMC_BLOCK_MAJOR;
        md->disk->first_minor = devidx * perdev_minors;
        md->disk->fops = &mmc_bdops;
        md->disk->private_data = md;
        md->disk->queue = md->queue.queue;
        md->parent = parent;
        set_disk_ro(md->disk, md->read_only || default_ro);
        md->disk->flags = GENHD_FL_EXT_DEVT;
        if (area_type & (MMC_BLK_DATA_AREA_RPMB | MMC_BLK_DATA_AREA_BOOT))
                md->disk->flags |= GENHD_FL_NO_PART_SCAN;

        /*
         * As discussed on lkml, GENHD_FL_REMOVABLE should:
         *
         * - be set for removable media with permanent block devices
         * - be unset for removable block devices with permanent media
         *
         * Since MMC block devices clearly fall under the second
         * case, we do not set GENHD_FL_REMOVABLE.  Userspace
         * should use the block device creation/destruction hotplug
         * messages to tell when the card is present.
         */

        snprintf(md->disk->disk_name, sizeof(md->disk->disk_name),
                 "mmcblk%u%s", card->host->index, subname ? subname : "");

        if (mmc_card_mmc(card))
                blk_queue_logical_block_size(md->queue.queue,
                                             card->ext_csd.data_sector_size);
        else
                blk_queue_logical_block_size(md->queue.queue, 512);

        set_capacity(md->disk, size);

        if (mmc_host_cmd23(card->host)) {
                if ((mmc_card_mmc(card) &&
                     card->csd.mmca_vsn >= CSD_SPEC_VER_3) ||
                    (mmc_card_sd(card) &&
                     card->scr.cmds & SD_SCR_CMD23_SUPPORT))
                        md->flags |= MMC_BLK_CMD23;
        }

        if (mmc_card_mmc(card) &&
            md->flags & MMC_BLK_CMD23 &&
            ((card->ext_csd.rel_param & EXT_CSD_WR_REL_PARAM_EN) ||
             card->ext_csd.rel_sectors)) {
                md->flags |= MMC_BLK_REL_WR;
                blk_queue_write_cache(md->queue.queue, true, true);
        }

        return md;

 err_putdisk:
        put_disk(md->disk);
 err_kfree:
        kfree(md);
 out:
        ida_simple_remove(&mmc_blk_ida, devidx);
        return ERR_PTR(ret);
}

static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
{
        sector_t size;

        if (!mmc_card_sd(card) && mmc_card_blockaddr(card)) {
                /*
                 * The EXT_CSD sector count is in number or 512 byte
                 * sectors.
                 */
                size = card->ext_csd.sectors;
        } else {
                /*
                 * The CSD capacity field is in units of read_blkbits.
                 * set_capacity takes units of 512 bytes.
                 */
                size = (typeof(sector_t))card->csd.capacity
                        << (card->csd.read_blkbits - 9);
        }

        return mmc_blk_alloc_req(card, &card->dev, size, false, NULL,
                                        MMC_BLK_DATA_AREA_MAIN);
}

static int mmc_blk_alloc_part(struct mmc_card *card,
                              struct mmc_blk_data *md,
                              unsigned int part_type,
                              sector_t size,
                              bool default_ro,
                              const char *subname,
                              int area_type)
{
        char cap_str[10];
        struct mmc_blk_data *part_md;

        part_md = mmc_blk_alloc_req(card, disk_to_dev(md->disk), size, default_ro,
                                    subname, area_type);
        if (IS_ERR(part_md))
                return PTR_ERR(part_md);
        part_md->part_type = part_type;
        list_add(&part_md->part, &md->part);

        string_get_size((u64)get_capacity(part_md->disk), 512, STRING_UNITS_2,
                        cap_str, sizeof(cap_str));
        pr_info("%s: %s %s partition %u %s\n",
               part_md->disk->disk_name, mmc_card_id(card),
               mmc_card_name(card), part_md->part_type, cap_str);
        return 0;
}

/* MMC Physical partitions consist of two boot partitions and
 * up to four general purpose partitions.
 * For each partition enabled in EXT_CSD a block device will be allocatedi
 * to provide access to the partition.
 */

static int mmc_blk_alloc_parts(struct mmc_card *card, struct mmc_blk_data *md)
{
        int idx, ret = 0;

        if (!mmc_card_mmc(card))
                return 0;

        for (idx = 0; idx < card->nr_parts; idx++) {
                if (card->part[idx].size) {
                        ret = mmc_blk_alloc_part(card, md,
                                card->part[idx].part_cfg,
                                card->part[idx].size >> 9,
                                card->part[idx].force_ro,
                                card->part[idx].name,
                                card->part[idx].area_type);
                        if (ret)
                                return ret;
                }
        }

        return ret;
}

static void mmc_blk_remove_req(struct mmc_blk_data *md)
{
        struct mmc_card *card;

        if (md) {
                /*
                 * Flush remaining requests and free queues. It
                 * is freeing the queue that stops new requests
                 * from being accepted.
                 */
                card = md->queue.card;
                spin_lock_irq(md->queue.queue->queue_lock);
                queue_flag_set(QUEUE_FLAG_BYPASS, md->queue.queue);
                spin_unlock_irq(md->queue.queue->queue_lock);
                blk_set_queue_dying(md->queue.queue);
                mmc_cleanup_queue(&md->queue);
                if (md->disk->flags & GENHD_FL_UP) {
                        device_remove_file(disk_to_dev(md->disk), &md->force_ro);
                        if ((md->area_type & MMC_BLK_DATA_AREA_BOOT) &&
                                        card->ext_csd.boot_ro_lockable)
                                device_remove_file(disk_to_dev(md->disk),
                                        &md->power_ro_lock);

                        del_gendisk(md->disk);
                }
                mmc_blk_put(md);
        }
}

static void mmc_blk_remove_parts(struct mmc_card *card,
                                 struct mmc_blk_data *md)
{
        struct list_head *pos, *q;
        struct mmc_blk_data *part_md;

        list_for_each_safe(pos, q, &md->part) {
                part_md = list_entry(pos, struct mmc_blk_data, part);
                list_del(pos);
                mmc_blk_remove_req(part_md);
        }
}

static int mmc_add_disk(struct mmc_blk_data *md)
{
        int ret;
        struct mmc_card *card = md->queue.card;

        device_add_disk(md->parent, md->disk);
        md->force_ro.show = force_ro_show;
        md->force_ro.store = force_ro_store;
        sysfs_attr_init(&md->force_ro.attr);
        md->force_ro.attr.name = "force_ro";
        md->force_ro.attr.mode = S_IRUGO | S_IWUSR;
        ret = device_create_file(disk_to_dev(md->disk), &md->force_ro);
        if (ret)
                goto force_ro_fail;

        if ((md->area_type & MMC_BLK_DATA_AREA_BOOT) &&
             card->ext_csd.boot_ro_lockable) {
                umode_t mode;

                if (card->ext_csd.boot_ro_lock & EXT_CSD_BOOT_WP_B_PWR_WP_DIS)
                        mode = S_IRUGO;
                else
                        mode = S_IRUGO | S_IWUSR;

                md->power_ro_lock.show = power_ro_lock_show;
                md->power_ro_lock.store = power_ro_lock_store;
                sysfs_attr_init(&md->power_ro_lock.attr);
                md->power_ro_lock.attr.mode = mode;
                md->power_ro_lock.attr.name =
                                        "ro_lock_until_next_power_on";
                ret = device_create_file(disk_to_dev(md->disk),
                                &md->power_ro_lock);
                if (ret)
                        goto power_ro_lock_fail;
        }
        return ret;

power_ro_lock_fail:
        device_remove_file(disk_to_dev(md->disk), &md->force_ro);
force_ro_fail:
        del_gendisk(md->disk);

        return ret;
}

static int mmc_blk_probe(struct mmc_card *card)
{
        struct mmc_blk_data *md, *part_md;
        char cap_str[10];

        /*
         * Check that the card supports the command class(es) we need.
         */
        if (!(card->csd.cmdclass & CCC_BLOCK_READ))
                return -ENODEV;

        mmc_fixup_device(card, mmc_blk_fixups);

        md = mmc_blk_alloc(card);
        if (IS_ERR(md))
                return PTR_ERR(md);

        string_get_size((u64)get_capacity(md->disk), 512, STRING_UNITS_2,
                        cap_str, sizeof(cap_str));
        pr_info("%s: %s %s %s %s\n",
                md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
                cap_str, md->read_only ? "(ro)" : "");

        if (mmc_blk_alloc_parts(card, md))
                goto out;

        dev_set_drvdata(&card->dev, md);

        if (mmc_add_disk(md))
                goto out;

        list_for_each_entry(part_md, &md->part, part) {
                if (mmc_add_disk(part_md))
                        goto out;
        }

        pm_runtime_set_autosuspend_delay(&card->dev, 3000);
        pm_runtime_use_autosuspend(&card->dev);

        /*
         * Don't enable runtime PM for SD-combo cards here. Leave that
         * decision to be taken during the SDIO init sequence instead.
         */
        if (card->type != MMC_TYPE_SD_COMBO) {
                pm_runtime_set_active(&card->dev);
                pm_runtime_enable(&card->dev);
        }

        return 0;

 out:
        mmc_blk_remove_parts(card, md);
        mmc_blk_remove_req(md);
        return 0;
}

static void mmc_blk_remove(struct mmc_card *card)
{
        struct mmc_blk_data *md = dev_get_drvdata(&card->dev);

        mmc_blk_remove_parts(card, md);
        pm_runtime_get_sync(&card->dev);
        mmc_claim_host(card->host);
        mmc_blk_part_switch(card, md);
        mmc_release_host(card->host);
        if (card->type != MMC_TYPE_SD_COMBO)
                pm_runtime_disable(&card->dev);
        pm_runtime_put_noidle(&card->dev);
        mmc_blk_remove_req(md);
        dev_set_drvdata(&card->dev, NULL);
}

static int _mmc_blk_suspend(struct mmc_card *card)
{
        struct mmc_blk_data *part_md;
        struct mmc_blk_data *md = dev_get_drvdata(&card->dev);

        if (md) {
                mmc_queue_suspend(&md->queue);
                list_for_each_entry(part_md, &md->part, part) {
                        mmc_queue_suspend(&part_md->queue);
                }
        }
        return 0;
}

static void mmc_blk_shutdown(struct mmc_card *card)
{
        _mmc_blk_suspend(card);
}

#ifdef CONFIG_PM_SLEEP
static int mmc_blk_suspend(struct device *dev)
{
        struct mmc_card *card = mmc_dev_to_card(dev);

        return _mmc_blk_suspend(card);
}

static int mmc_blk_resume(struct device *dev)
{
        struct mmc_blk_data *part_md;
        struct mmc_blk_data *md = dev_get_drvdata(dev);

        if (md) {
                /*
                 * Resume involves the card going into idle state,
                 * so current partition is always the main one.
                 */
                md->part_curr = md->part_type;
                mmc_queue_resume(&md->queue);
                list_for_each_entry(part_md, &md->part, part) {
                        mmc_queue_resume(&part_md->queue);
                }
        }
        return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(mmc_blk_pm_ops, mmc_blk_suspend, mmc_blk_resume);

static struct mmc_driver mmc_driver = {
        .drv            = {
                .name   = "mmcblk",
                .pm     = &mmc_blk_pm_ops,
        },
        .probe          = mmc_blk_probe,
        .remove         = mmc_blk_remove,
        .shutdown       = mmc_blk_shutdown,
};

static int __init mmc_blk_init(void)
{
        int res;

        if (perdev_minors != CONFIG_MMC_BLOCK_MINORS)
                pr_info("mmcblk: using %d minors per device\n", perdev_minors);

        max_devices = min(MAX_DEVICES, (1 << MINORBITS) / perdev_minors);

        res = register_blkdev(MMC_BLOCK_MAJOR, "mmc");
        if (res)
                goto out;

        res = mmc_register_driver(&mmc_driver);
        if (res)
                goto out2;

        return 0;
 out2:
        unregister_blkdev(MMC_BLOCK_MAJOR, "mmc");
 out:
        return res;
}

static void __exit mmc_blk_exit(void)
{
        mmc_unregister_driver(&mmc_driver);
        unregister_blkdev(MMC_BLOCK_MAJOR, "mmc");
}

module_init(mmc_blk_init);
module_exit(mmc_blk_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");