/*
* The device operations structure.
*/
static struct block_device_operations sbull_ops = {
.owner = THIS_MODULE,
.open = sbull_open,
.release = sbull_release,
.media_changed = sbull_media_changed,
.revalidate_disk = sbull_revalidate,
.ioctl = sbull_ioctl,
.getgeo = sbull_getgeo,
};
/*
* Set up our internal device.
*/
// 初始化设备结构体 static struct sbull_dev *Devices中的成员
static void setup_device(struct sbull_dev *dev, int which)
{
/*
* Get some memory.
*/
memset (dev, 0, sizeof (struct sbull_dev));
dev->size = nsectors*hardsect_size;
// 分配一片虚拟地址连续的内存空间，作为块设备。
dev->data = vmalloc(dev->size);
if (dev->data == NULL) {
printk (KERN_NOTICE "vmalloc failure.\n");
return;
}
spin_lock_init(&dev->lock);
/*
* The timer which "invalidates" the device.
*/
init_timer(&dev->timer);
dev->timer.data = (unsigned long) dev;
dev->timer.function = sbull_invalidate;
/*
* The I/O queue, depending on whether we are using our own
* make_request function or not.
*/
switch (request_mode) {
case RM_NOQUEUE:
dev->queue = blk_alloc_queue(GFP_KERNEL);
if (dev->queue == NULL)
goto out_vfree;
blk_queue_make_request(dev->queue, sbull_make_request);
break;
case RM_FULL:
dev->queue = blk_init_queue(sbull_full_request, &dev->lock);
if (dev->queue == NULL)
goto out_vfree;
break;
default:
printk(KERN_NOTICE "Bad request mode %d, using simple\n", request_mode);
/* fall into.. */
case RM_SIMPLE:
dev->queue = blk_init_queue(sbull_request, &dev->lock);
if (dev->queue == NULL)
goto out_vfree;
break;
}
blk_queue_hardsect_size(dev->queue, hardsect_size);
dev->queue->queuedata = dev;
/*
* And the gendisk structure.
*/
dev->gd = alloc_disk(SBULL_MINORS);
if (! dev->gd) {
printk (KERN_NOTICE "alloc_disk failure\n");
goto out_vfree;
}
dev->gd->major = sbull_major;
dev->gd->first_minor = which*SBULL_MINORS;
dev->gd->fops = &sbull_ops;
dev->gd->queue = dev->queue;
dev->gd->private_data = dev;
snprintf (dev->gd->disk_name, 32, "sbull%c", which + 'a');
set_capacity(dev->gd, nsectors*(hardsect_size/KERNEL_SECTOR_SIZE));
add_disk(dev->gd);
return;
out_vfree:
if (dev->data)
vfree(dev->data);
}