#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/blkdev.h>
+#include <linux/smp_lock.h>
#include <linux/hdreg.h>
#include <linux/virtio.h>
#include <linux/virtio_blk.h>
return blk_execute_rq(vblk->disk->queue, vblk->disk, req, false);
}
-static int virtblk_ioctl(struct block_device *bdev, fmode_t mode,
+static int virtblk_locked_ioctl(struct block_device *bdev, fmode_t mode,
unsigned cmd, unsigned long data)
{
struct gendisk *disk = bdev->bd_disk;
struct virtio_blk *vblk = disk->private_data;
- if (cmd == 0x56424944) { /* 'VBID' */
- void __user *usr_data = (void __user *)data;
- char id_str[VIRTIO_BLK_ID_BYTES];
- int err;
-
- err = virtblk_get_id(disk, id_str);
- if (!err && copy_to_user(usr_data, id_str, VIRTIO_BLK_ID_BYTES))
- err = -EFAULT;
- return err;
- }
/*
* Only allow the generic SCSI ioctls if the host can support it.
*/
(void __user *)data);
}
+static int virtblk_ioctl(struct block_device *bdev, fmode_t mode,
+ unsigned int cmd, unsigned long param)
+{
+ int ret;
+
+ lock_kernel();
+ ret = virtblk_locked_ioctl(bdev, mode, cmd, param);
+ unlock_kernel();
+
+ return ret;
+}
+
/* We provide getgeo only to please some old bootloader/partitioning tools */
static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo)
{
}
static const struct block_device_operations virtblk_fops = {
- .locked_ioctl = virtblk_ioctl,
+ .ioctl = virtblk_ioctl,
.owner = THIS_MODULE,
.getgeo = virtblk_getgeo,
};
return index << PART_BITS;
}
+static ssize_t virtblk_serial_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct gendisk *disk = dev_to_disk(dev);
+ int err;
+
+ /* sysfs gives us a PAGE_SIZE buffer */
+ BUILD_BUG_ON(PAGE_SIZE < VIRTIO_BLK_ID_BYTES);
+
+ buf[VIRTIO_BLK_ID_BYTES] = '\0';
+ err = virtblk_get_id(disk, buf);
+ if (!err)
+ return strlen(buf);
+
+ if (err == -EIO) /* Unsupported? Make it empty. */
+ return 0;
+
+ return err;
+}
+DEVICE_ATTR(serial, S_IRUGO, virtblk_serial_show, NULL);
+
static int __devinit virtblk_probe(struct virtio_device *vdev)
{
struct virtio_blk *vblk;
vblk->disk->driverfs_dev = &vdev->dev;
index++;
- /* If barriers are supported, tell block layer that queue is ordered */
- if (virtio_has_feature(vdev, VIRTIO_BLK_F_FLUSH))
- blk_queue_ordered(q, QUEUE_ORDERED_DRAIN_FLUSH, NULL);
- else if (virtio_has_feature(vdev, VIRTIO_BLK_F_BARRIER))
- blk_queue_ordered(q, QUEUE_ORDERED_TAG, NULL);
+ if (virtio_has_feature(vdev, VIRTIO_BLK_F_FLUSH)) {
+ /*
+ * If the FLUSH feature is supported we do have support for
+ * flushing a volatile write cache on the host. Use that
+ * to implement write barrier support.
+ */
+ blk_queue_ordered(q, QUEUE_ORDERED_DRAIN_FLUSH);
+ } else if (virtio_has_feature(vdev, VIRTIO_BLK_F_BARRIER)) {
+ /*
+ * If the BARRIER feature is supported the host expects us
+ * to order request by tags. This implies there is not
+ * volatile write cache on the host, and that the host
+ * never re-orders outstanding I/O. This feature is not
+ * useful for real life scenarious and deprecated.
+ */
+ blk_queue_ordered(q, QUEUE_ORDERED_TAG);
+ } else {
+ /*
+ * If the FLUSH feature is not supported we must assume that
+ * the host does not perform any kind of volatile write
+ * caching. We still need to drain the queue to provider
+ * proper barrier semantics.
+ */
+ blk_queue_ordered(q, QUEUE_ORDERED_DRAIN);
+ }
/* If disk is read-only in the host, the guest should obey */
if (virtio_has_feature(vdev, VIRTIO_BLK_F_RO))
add_disk(vblk->disk);
+ err = device_create_file(disk_to_dev(vblk->disk), &dev_attr_serial);
+ if (err)
+ goto out_del_disk;
+
return 0;
+out_del_disk:
+ del_gendisk(vblk->disk);
+ blk_cleanup_queue(vblk->disk->queue);
out_put_disk:
put_disk(vblk->disk);
out_mempool: