freebsd-dev/sys/geom/geom_disk.h
John Polstra a7e69e8b7d Fix a bug that caused some /dev entries to continue to exist after
the underlying drive had been hot-unplugged from the system.  Here
is a specific example.  Filesystem code had opened /dev/da1s1e.
Subsequently, the drive was hot-unplugged.  This (correctly) caused
all of the associated /dev/da1* entries to be deleted.  When the
filesystem later realized that the drive was gone it closed the
device, reducing the write-access counts to 0 on the geom providers
for da1s1e, da1s1, and da1.  This caused geom to re-taste the
providers, resulting in the devices being created again.  When the
drive was hot-plugged back in, it resulted in duplicate /dev entries
for da1s1e, da1s1, and da1.

This fix adds a new disk_gone() function which is called by CAM when a
drive goes away.  It orphans all of the providers associated with the
drive, setting an error condition of ENXIO in each one.  In addition,
we prevent a re-taste on last close for writing if an error condition
has been set in the provider.

Sponsored by:   Isilon Systems
Reviewed by:    phk
MFC after:      1 week
2005-11-18 02:43:49 +00:00

105 lines
3.3 KiB
C

/*-
* Copyright (c) 2003 Poul-Henning Kamp
* All rights reserved.
*
* This software was developed for the FreeBSD Project by Poul-Henning Kamp
* and NAI Labs, the Security Research Division of Network Associates, Inc.
* under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
* DARPA CHATS research program.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The names of the authors may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _GEOM_GEOM_DISK_H_
#define _GEOM_GEOM_DISK_H_
#ifdef _KERNEL
#include <sys/queue.h>
#include <sys/_lock.h>
#include <sys/_mutex.h>
struct disk;
typedef int disk_open_t(struct disk *);
typedef int disk_close_t(struct disk *);
typedef void disk_strategy_t(struct bio *bp);
typedef int disk_ioctl_t(struct disk *, u_long cmd, void *data,
int fflag, struct thread *td);
/* NB: disk_ioctl_t SHALL be cast'able to d_ioctl_t */
struct g_geom;
struct devstat;
struct disk {
/* Fields which are private to geom_disk */
struct g_geom *d_geom;
struct devstat *d_devstat;
int d_destroyed;
/* Shared fields */
u_int d_flags;
const char *d_name;
u_int d_unit;
struct bio_queue_head *d_queue;
struct mtx *d_lock;
/* Disk methods */
disk_open_t *d_open;
disk_close_t *d_close;
disk_strategy_t *d_strategy;
disk_ioctl_t *d_ioctl;
dumper_t *d_dump;
/* Info fields from driver to geom_disk.c. Valid when open */
u_int d_sectorsize;
off_t d_mediasize;
u_int d_fwsectors;
u_int d_fwheads;
u_int d_maxsize;
u_int d_stripeoffset;
u_int d_stripesize;
/* Fields private to the driver */
void *d_drv1;
};
#define DISKFLAG_NEEDSGIANT 0x1
#define DISKFLAG_OPEN 0x2
#define DISKFLAG_CANDELETE 0x4
struct disk *disk_alloc(void);
void disk_create(struct disk *disk, int version);
void disk_destroy(struct disk *disk);
void disk_gone(struct disk *disk);
#define DISK_VERSION_00 0x58561059
#define DISK_VERSION DISK_VERSION_00
#endif /* _KERNEL */
#endif /* _GEOM_GEOM_DISK_H_ */