static int mmc_blk_open(struct inode *inode, struct file *filp)
{
	struct mmc_blk_data *md;
	int ret = -ENXIO;

	md = mmc_blk_get(inode->i_bdev->bd_disk);
	if (md) {
		if (md->usage == 2)
			check_disk_change(inode->i_bdev);
		ret = 0;

		if ((filp->f_mode & FMODE_WRITE) &&
			mmc_blk_readonly(md->queue.card))
			ret = -EROFS;
	}

	return ret;
}
示例#2
0
static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
{
	struct mmc_blk_data *md;
	int devidx, ret;

	devidx = find_first_zero_bit(dev_use, MMC_NUM_MINORS);
	if (devidx >= MMC_NUM_MINORS)
		return ERR_PTR(-ENOSPC);
	__set_bit(devidx, dev_use);

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

	memset(md, 0, sizeof(struct mmc_blk_data));

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

	/*
	 * Both SD and MMC specifications state (although a bit
	 * unclearly in the MMC case) that a block size of 512
	 * bytes must always be supported by the card.
	 */
	md->block_bits = 9;

	md->disk = alloc_disk(1 << MMC_SHIFT);
	if (md->disk == NULL) {
		ret = -ENOMEM;
		goto err_kfree;
	}

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

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

	md->queue.prep_fn = mmc_blk_prep_rq;
	md->queue.issue_fn = mmc_blk_issue_rq;
	md->queue.data = md;

	md->disk->major	= major;
	md->disk->first_minor = devidx << MMC_SHIFT;
	md->disk->fops = &mmc_bdops;
	md->disk->private_data = md;
	md->disk->queue = md->queue.queue;
	md->disk->driverfs_dev = &card->dev;

	printk("mmc: major= %d, minor= %d \n",md->disk->major, md->disk->first_minor );

	/*
	 * 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.
	 */

	sprintf(md->disk->disk_name, "mmcblk%d", devidx);

	blk_queue_hardsect_size(md->queue.queue, 1 << md->block_bits);

	/*
	 * The CSD capacity field is in units of read_blkbits.
	 * set_capacity takes units of 512 bytes.
	 *
	 * jsgood: sector mode card size patch	 
	 */
	if (!mmc_card_blockaddr(card))
		set_capacity(md->disk, card->csd.capacity << (card->csd.read_blkbits - 9));
	else
		set_capacity(md->disk, card->csd.capacity);

	return md;

 err_putdisk:
	put_disk(md->disk);
 err_kfree:
	kfree(md);
 out:
	return ERR_PTR(ret);
}