The DO_IT ioctl does a lot of things to handle the connection. This patch splits the DO_IT ioctl routine into three functions nbd_connection_start()/run()/stop(). This makes it easier to read and allows other functions to call the same code. This patch prepares the DO_IT code for nbd-root device.
Signed-off-by: Markus Pargmann <[email protected]> --- drivers/block/nbd.c | 146 ++++++++++++++++++++++++++++++++-------------------- 1 file changed, 91 insertions(+), 55 deletions(-) diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 6bd7df2ff648..0ff6ebbec252 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -596,6 +596,95 @@ static void do_nbd_request(struct request_queue *q) } } +static int nbd_connection_start(struct block_device *bdev, + struct nbd_device *nbd) +{ + if (nbd->flags & NBD_FLAG_READ_ONLY) + set_device_ro(bdev, true); + if (nbd->flags & NBD_FLAG_SEND_TRIM) + queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, nbd->disk->queue); + if (nbd->flags & NBD_FLAG_SEND_FLUSH) + blk_queue_flush(nbd->disk->queue, REQ_FLUSH); + else + blk_queue_flush(nbd->disk->queue, 0); + return 0; +} + +static int nbd_connection_run(struct nbd_device *nbd) +{ + struct task_struct *thread; + int error; + + thread = kthread_run(nbd_thread, nbd, "%s", nbd->disk->disk_name); + if (IS_ERR(thread)) { + mutex_lock(&nbd->tx_lock); + return PTR_ERR(thread); + } + + error = nbd_do_it(nbd); + + kthread_stop(thread); + + return error; +} + +/* + * Call with tx_lock held + */ +static int nbd_connection_stop(struct block_device *bdev, + struct nbd_device *nbd) +{ + struct socket *sock; + + sock_shutdown(nbd, 0); + sock = nbd->sock; + nbd->sock = NULL; + nbd_clear_que(nbd); + dev_warn(disk_to_dev(nbd->disk), "queue cleared\n"); + kill_bdev(bdev); + queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, nbd->disk->queue); + set_device_ro(bdev, false); + if (sock) + sockfd_put(sock); + + nbd->flags = 0; + nbd->bytesize = 0; + bdev->bd_inode->i_size = 0; + set_capacity(nbd->disk, 0); + + if (max_part > 0) + ioctl_by_bdev(bdev, BLKRRPART, 0); + if (nbd->disconnect) /* user requested, ignore socket errors */ + return 0; + + return nbd->harderror; +} + +/* + * Call with tx_lock held + */ +static int nbd_connection_handler(struct block_device *bdev, + struct nbd_device *nbd) +{ + int error; + + mutex_unlock(&nbd->tx_lock); + + error = nbd_connection_start(bdev, nbd); + if (error) + return error; + + error = nbd_connection_run(nbd); + + mutex_lock(&nbd->tx_lock); + if (error) + return error; + + error = nbd_connection_stop(bdev, nbd); + + return error; +} + /* Must be called with tx_lock held */ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd, @@ -684,61 +773,8 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd, set_capacity(nbd->disk, nbd->bytesize >> 9); return 0; - case NBD_DO_IT: { - struct task_struct *thread; - struct socket *sock; - int error; - - if (nbd->pid) - return -EBUSY; - if (!nbd->sock) - return -EINVAL; - - mutex_unlock(&nbd->tx_lock); - - if (nbd->flags & NBD_FLAG_READ_ONLY) - set_device_ro(bdev, true); - if (nbd->flags & NBD_FLAG_SEND_TRIM) - queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, - nbd->disk->queue); - if (nbd->flags & NBD_FLAG_SEND_FLUSH) - blk_queue_flush(nbd->disk->queue, REQ_FLUSH); - else - blk_queue_flush(nbd->disk->queue, 0); - - thread = kthread_run(nbd_thread, nbd, "%s", - nbd->disk->disk_name); - if (IS_ERR(thread)) { - mutex_lock(&nbd->tx_lock); - return PTR_ERR(thread); - } - - error = nbd_do_it(nbd); - kthread_stop(thread); - - mutex_lock(&nbd->tx_lock); - if (error) - return error; - sock_shutdown(nbd, 0); - sock = nbd->sock; - nbd->sock = NULL; - nbd_clear_que(nbd); - dev_warn(disk_to_dev(nbd->disk), "queue cleared\n"); - kill_bdev(bdev); - queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, nbd->disk->queue); - set_device_ro(bdev, false); - if (sock) - sockfd_put(sock); - nbd->flags = 0; - nbd->bytesize = 0; - bdev->bd_inode->i_size = 0; - set_capacity(nbd->disk, 0); - if (max_part > 0) - ioctl_by_bdev(bdev, BLKRRPART, 0); - if (nbd->disconnect) /* user requested, ignore socket errors */ - return 0; - return nbd->harderror; - } + case NBD_DO_IT: + return nbd_connection_handler(bdev, nbd); case NBD_CLEAR_QUE: /* -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
