block: floppy: fix rmmod lockup

[safe/jmp/linux-2.6] / drivers / block / virtio_blk.c

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 54a8017..3b1a68d 100644 (file)
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -7,8 +7,10 @@
 #include <linux/scatterlist.h>
 
 #define VIRTIO_MAX_SG  (3+MAX_PHYS_SEGMENTS)
+#define PART_BITS 4
+
+static int major, index;
 
-static unsigned char virtblk_index = 'a';
 struct virtio_blk
 {
        spinlock_t lock;
@@ -152,18 +154,37 @@ static int virtblk_ioctl(struct inode *inode, struct file *filp,
                              (void __user *)data);
 }
 
+/* We provide getgeo only to please some old bootloader/partitioning tools */
+static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo)
+{
+       /* some standard values, similar to sd */
+       geo->heads = 1 << 6;
+       geo->sectors = 1 << 5;
+       geo->cylinders = get_capacity(bd->bd_disk) >> 11;
+       return 0;
+}
+
 static struct block_device_operations virtblk_fops = {
-       .ioctl = virtblk_ioctl,
-       .owner = THIS_MODULE,
+       .ioctl  = virtblk_ioctl,
+       .owner  = THIS_MODULE,
+       .getgeo = virtblk_getgeo,
 };
 
+static int index_to_minor(int index)
+{
+       return index << PART_BITS;
+}
+
 static int virtblk_probe(struct virtio_device *vdev)
 {
        struct virtio_blk *vblk;
-       int err, major;
+       int err;
        u64 cap;
        u32 v;
 
+       if (index_to_minor(index) >= 1 << MINORBITS)
+               return -ENOSPC;
+
        vdev->priv = vblk = kmalloc(sizeof(*vblk), GFP_KERNEL);
        if (!vblk) {
                err = -ENOMEM;
@@ -187,17 +208,11 @@ static int virtblk_probe(struct virtio_device *vdev)
                goto out_free_vq;
        }
 
-       major = register_blkdev(0, "virtblk");
-       if (major < 0) {
-               err = major;
-               goto out_mempool;
-       }
-
        /* FIXME: How many partitions?  How long is a piece of string? */
-       vblk->disk = alloc_disk(1 << 4);
+       vblk->disk = alloc_disk(1 << PART_BITS);
        if (!vblk->disk) {
                err = -ENOMEM;
-               goto out_unregister_blkdev;
+               goto out_mempool;
        }
 
        vblk->disk->queue = blk_init_queue(do_virtblk_request, &vblk->lock);
@@ -206,11 +221,24 @@ static int virtblk_probe(struct virtio_device *vdev)
                goto out_put_disk;
        }
 
-       sprintf(vblk->disk->disk_name, "vd%c", virtblk_index++);
+       if (index < 26) {
+               sprintf(vblk->disk->disk_name, "vd%c", 'a' + index % 26);
+       } else if (index < (26 + 1) * 26) {
+               sprintf(vblk->disk->disk_name, "vd%c%c",
+                       'a' + index / 26 - 1, 'a' + index % 26);
+       } else {
+               const unsigned int m1 = (index / 26 - 1) / 26 - 1;
+               const unsigned int m2 = (index / 26 - 1) % 26;
+               const unsigned int m3 =  index % 26;
+               sprintf(vblk->disk->disk_name, "vd%c%c%c",
+                       'a' + m1, 'a' + m2, 'a' + m3);
+       }
+
        vblk->disk->major = major;
-       vblk->disk->first_minor = 0;
+       vblk->disk->first_minor = index_to_minor(index);
        vblk->disk->private_data = vblk;
        vblk->disk->fops = &virtblk_fops;
+       index++;
 
        /* If barriers are supported, tell block layer that queue is ordered */
        if (vdev->config->feature(vdev, VIRTIO_BLK_F_BARRIER))
@@ -247,8 +275,6 @@ static int virtblk_probe(struct virtio_device *vdev)
 
 out_put_disk:
        put_disk(vblk->disk);
-out_unregister_blkdev:
-       unregister_blkdev(major, "virtblk");
 out_mempool:
        mempool_destroy(vblk->pool);
 out_free_vq:
@@ -264,12 +290,16 @@ static void virtblk_remove(struct virtio_device *vdev)
        struct virtio_blk *vblk = vdev->priv;
        int major = vblk->disk->major;
 
+       /* Nothing should be pending. */
        BUG_ON(!list_empty(&vblk->reqs));
+
+       /* Stop all the virtqueues. */
+       vdev->config->reset(vdev);
+
        blk_cleanup_queue(vblk->disk->queue);
        put_disk(vblk->disk);
        unregister_blkdev(major, "virtblk");
        mempool_destroy(vblk->pool);
-       /* There should be nothing in the queue now, so no need to shutdown */
        vdev->config->del_vq(vblk->vq);
        kfree(vblk);
 }
@@ -289,11 +319,15 @@ static struct virtio_driver virtio_blk = {
 
 static int __init init(void)
 {
+       major = register_blkdev(0, "virtblk");
+       if (major < 0)
+               return major;
        return register_virtio_driver(&virtio_blk);
 }
 
 static void __exit fini(void)
 {
+       unregister_blkdev(major, "virtblk");
        unregister_virtio_driver(&virtio_blk);
 }
 module_init(init);