NBD: set uninitialized devices to size 0

This fixes errors with utilities (such as LVM's vgscan) that try to scan all
devices.  Previously this would generate read errors when uninitialized nbd
devices were scanned:

# vgscan
   Reading all physical volumes.  This may take a while...
   /dev/nbd0: read failed after 0 of 1024 at 0: Input/output error
   /dev/nbd0: read failed after 0 of 1024 at 509804544: Input/output error
   /dev/nbd0: read failed after 0 of 2048 at 0: Input/output error
   /dev/nbd1: read failed after 0 of 1024 at 509804544: Input/output error
   /dev/nbd1: read failed after 0 of 2048 at 0: Input/output error

 From now on, uninitialized nbd devices will have size zero, which
prevents these errors.

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Paul Clements 2007-10-16 23:27:36 -07:00 committed by Linus Torvalds
parent dff4982f5c
commit 4b86a87256

View file

@ -578,6 +578,9 @@ static int nbd_ioctl(struct inode *inode, struct file *file,
printk(KERN_WARNING "%s: queue cleared\n", lo->disk->disk_name);
if (file)
fput(file);
lo->bytesize = 0;
inode->i_bdev->bd_inode->i_size = 0;
set_capacity(lo->disk, 0);
return lo->harderror;
case NBD_CLEAR_QUE:
/*
@ -655,14 +658,14 @@ static int __init nbd_init(void)
mutex_init(&nbd_dev[i].tx_lock);
init_waitqueue_head(&nbd_dev[i].active_wq);
nbd_dev[i].blksize = 1024;
nbd_dev[i].bytesize = 0x7ffffc00ULL << 10; /* 2TB */
nbd_dev[i].bytesize = 0;
disk->major = NBD_MAJOR;
disk->first_minor = i;
disk->fops = &nbd_fops;
disk->private_data = &nbd_dev[i];
disk->flags |= GENHD_FL_SUPPRESS_PARTITION_INFO;
sprintf(disk->disk_name, "nbd%d", i);
set_capacity(disk, 0x7ffffc00ULL << 1); /* 2 TB */
set_capacity(disk, 0);
add_disk(disk);
}