kernel-ark/include/linux/nbd.h
Paul Clements c378f70adb nbd: correct disconnect behavior
Currently, when a disconnect is requested by the user (via NBD_DISCONNECT
ioctl) the return from NBD_DO_IT is undefined (it is usually one of
several error codes).  This means that nbd-client does not know if a
manual disconnect was performed or whether a network error occurred.
Because of this, nbd-client's persist mode (which tries to reconnect after
error, but not after manual disconnect) does not always work correctly.

This change fixes this by causing NBD_DO_IT to always return 0 if a user
requests a disconnect.  This means that nbd-client can correctly either
persist the connection (if an error occurred) or disconnect (if the user
requested it).

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Acked-by: Rob Landley <rob@landley.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:08:05 -07:00

48 lines
1.3 KiB
C

/*
* 1999 Copyright (C) Pavel Machek, pavel@ucw.cz. This code is GPL.
* 1999/11/04 Copyright (C) 1999 VMware, Inc. (Regis "HPReg" Duchesne)
* Made nbd_end_request() use the io_request_lock
* 2001 Copyright (C) Steven Whitehouse
* New nbd_end_request() for compatibility with new linux block
* layer code.
* 2003/06/24 Louis D. Langholtz <ldl@aros.net>
* Removed unneeded blksize_bits field from nbd_device struct.
* Cleanup PARANOIA usage & code.
* 2004/02/19 Paul Clements
* Removed PARANOIA, plus various cleanup and comments
*/
#ifndef LINUX_NBD_H
#define LINUX_NBD_H
#include <linux/wait.h>
#include <linux/mutex.h>
#include <uapi/linux/nbd.h>
struct request;
struct nbd_device {
int flags;
int harderror; /* Code of hard error */
struct socket * sock;
struct file * file; /* If == NULL, device is not ready, yet */
int magic;
spinlock_t queue_lock;
struct list_head queue_head; /* Requests waiting result */
struct request *active_req;
wait_queue_head_t active_wq;
struct list_head waiting_queue; /* Requests to be sent */
wait_queue_head_t waiting_wq;
struct mutex tx_lock;
struct gendisk *disk;
int blksize;
u64 bytesize;
pid_t pid; /* pid of nbd-client, if attached */
int xmit_timeout;
int disconnect; /* a disconnect has been requested by user */
};
#endif