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; }
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); }