From: Lou Langholtz This fourth patch simply removes the blksize_bits field from the nbd_device struct and driver implementation. How this field made it into this driver to begin with is a mystery (where was Al Viro when that patch was submitted??). :-) This patch modifies both drivers/block/nbd.c and include/linux/nbd.h files. It's intended to be applied incrementally on top of my third patch (for enhanced diagnostics support). drivers/block/nbd.c | 13 ++++--------- include/linux/nbd.h | 3 ++- 2 files changed, 6 insertions(+), 10 deletions(-) diff -puN drivers/block/nbd.c~nbd-remove-blksize-bits drivers/block/nbd.c --- 25/drivers/block/nbd.c~nbd-remove-blksize-bits 2003-06-26 18:39:31.000000000 -0700 +++ 25-akpm/drivers/block/nbd.c 2003-06-26 18:39:31.000000000 -0700 @@ -33,6 +33,8 @@ * from sending/receiving disk data. * 03-06-23 Cosmetic changes. * 03-06-23 Enhance diagnostics support. + * 03-06-24 Remove unneeded blksize_bits field from nbd_device struct. + * * * possible FIXME: make set_sock / set_blksize / set_size / do_it one syscall * why not: would need verify_area and friends, would share yet another @@ -535,7 +537,7 @@ static int nbd_ioctl(struct inode *inode unsigned int cmd, unsigned long arg) { struct nbd_device *lo = inode->i_bdev->bd_disk->private_data; - int error, temp; + int error; struct request sreq ; /* Anyone capable of this syscall can do *real bad* things */ @@ -600,12 +602,6 @@ static int nbd_ioctl(struct inode *inode if ((arg & (arg-1)) || (arg < 512) || (arg > PAGE_SIZE)) return -EINVAL; lo->blksize = arg; - temp = arg >> 9; - lo->blksize_bits = 9; - while (temp > 1) { - lo->blksize_bits++; - temp >>= 1; - } lo->bytesize &= ~(lo->blksize-1); set_capacity(lo->disk, lo->bytesize >> 9); return 0; @@ -614,7 +610,7 @@ static int nbd_ioctl(struct inode *inode set_capacity(lo->disk, lo->bytesize >> 9); return 0; case NBD_SET_SIZE_BLOCKS: - lo->bytesize = ((u64) arg) << lo->blksize_bits; + lo->bytesize = ((u64) arg) * lo->blksize; set_capacity(lo->disk, lo->bytesize >> 9); return 0; case NBD_DO_IT: @@ -717,7 +713,6 @@ static int __init nbd_init(void) INIT_LIST_HEAD(&nbd_dev[i].queue_head); init_MUTEX(&nbd_dev[i].tx_lock); nbd_dev[i].blksize = 1024; - nbd_dev[i].blksize_bits = 10; nbd_dev[i].bytesize = ((u64)0x7ffffc00) << 10; /* 2TB */ disk->major = NBD_MAJOR; disk->first_minor = i; diff -puN include/linux/nbd.h~nbd-remove-blksize-bits include/linux/nbd.h --- 25/include/linux/nbd.h~nbd-remove-blksize-bits 2003-06-26 18:39:31.000000000 -0700 +++ 25-akpm/include/linux/nbd.h 2003-06-26 18:39:31.000000000 -0700 @@ -5,6 +5,8 @@ * 2001 Copyright (C) Steven Whitehouse * New nbd_end_request() for compatibility with new linux block * layer code. + * 2003/06/24 Louis D. Langholtz + * Removed unneeded blksize_bits field from nbd_device struct. */ #ifndef LINUX_NBD_H @@ -50,7 +52,6 @@ struct nbd_device { struct semaphore tx_lock; struct gendisk *disk; int blksize; - int blksize_bits; u64 bytesize; }; _