freebsd-dev/sys/geom/gate/g_gate.h
Alexander Motin 351d0fa6df Fix GEOM_GATE orphanization.
Previous code closed and destroyed direct read consumer even with I/O still
in progress.  This patch adds locking and request counting to postpone the
close till the last of running requests completes.

MFC after:	2 weeks
Sponsored by:	iXsystems, Inc.
2019-12-28 17:52:53 +00:00

164 lines
4.9 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2004-2009 Pawel Jakub Dawidek <pjd@FreeBSD.org>
* All rights reserved.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS 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 AUTHORS 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 _G_GATE_H_
#define _G_GATE_H_
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/queue.h>
#include <geom/geom.h>
#define G_GATE_CLASS_NAME "GATE"
#define G_GATE_PROVIDER_NAME "ggate"
#define G_GATE_MOD_NAME "ggate"
#define G_GATE_CTL_NAME "ggctl"
#define G_GATE_VERSION 3
/*
* Maximum number of request that can be stored in
* the queue when there are no workers.
*/
#define G_GATE_MAX_QUEUE_SIZE 4096
#define G_GATE_FLAG_READONLY 0x0001
#define G_GATE_FLAG_WRITEONLY 0x0002
#define G_GATE_FLAG_DESTROY 0x1000
#define G_GATE_USERFLAGS (G_GATE_FLAG_READONLY | G_GATE_FLAG_WRITEONLY)
/*
* Pick unit number automatically in /dev/ggate<unit>.
*/
#define G_GATE_UNIT_AUTO (-1)
/*
* Full provider name is given, so don't use ggate<unit>.
*/
#define G_GATE_NAME_GIVEN (-2)
#define G_GATE_CMD_CREATE _IOWR('m', 0, struct g_gate_ctl_create)
#define G_GATE_CMD_MODIFY _IOWR('m', 1, struct g_gate_ctl_modify)
#define G_GATE_CMD_DESTROY _IOWR('m', 2, struct g_gate_ctl_destroy)
#define G_GATE_CMD_CANCEL _IOWR('m', 3, struct g_gate_ctl_cancel)
#define G_GATE_CMD_START _IOWR('m', 4, struct g_gate_ctl_io)
#define G_GATE_CMD_DONE _IOWR('m', 5, struct g_gate_ctl_io)
#define G_GATE_INFOSIZE 2048
#ifdef _KERNEL
/*
* 'P:' means 'Protected by'.
*/
struct g_gate_softc {
char *sc_name; /* P: (read-only) */
int sc_unit; /* P: (read-only) */
int sc_ref; /* P: g_gate_list_mtx */
struct g_provider *sc_provider; /* P: (read-only) */
uint32_t sc_flags; /* P: sc_queue_mtx */
struct bio_queue_head sc_inqueue; /* P: sc_queue_mtx */
struct bio_queue_head sc_outqueue; /* P: sc_queue_mtx */
struct mtx sc_queue_mtx;
uint32_t sc_queue_count; /* P: sc_queue_mtx */
uint32_t sc_queue_size; /* P: (read-only) */
u_int sc_timeout; /* P: (read-only) */
struct g_consumer *sc_readcons; /* P: sc_read_mtx */
off_t sc_readoffset; /* P: sc_read_mtx */
struct callout sc_callout; /* P: (modified only
from callout
thread) */
uintptr_t sc_seq; /* P: sc_queue_mtx */
LIST_ENTRY(g_gate_softc) sc_next; /* P: g_gate_list_mtx */
char sc_info[G_GATE_INFOSIZE]; /* P: (read-only) */
struct mtx sc_read_mtx;
};
#define G_GATE_DEBUG(lvl, ...) \
_GEOM_DEBUG("GEOM_GATE", g_gate_debug, (lvl), NULL, __VA_ARGS__)
#define G_GATE_LOGREQ(lvl, bp, ...) \
_GEOM_DEBUG("GEOM_GATE", g_gate_debug, (lvl), (bp), __VA_ARGS__)
#endif /* !_KERNEL */
struct g_gate_ctl_create {
u_int gctl_version;
off_t gctl_mediasize;
u_int gctl_sectorsize;
u_int gctl_flags;
u_int gctl_maxcount;
u_int gctl_timeout;
char gctl_name[NAME_MAX];
char gctl_info[G_GATE_INFOSIZE];
char gctl_readprov[NAME_MAX];
off_t gctl_readoffset;
int gctl_unit; /* in/out */
};
#define GG_MODIFY_MEDIASIZE 0x01
#define GG_MODIFY_INFO 0x02
#define GG_MODIFY_READPROV 0x04
#define GG_MODIFY_READOFFSET 0x08
struct g_gate_ctl_modify {
u_int gctl_version;
int gctl_unit;
uint32_t gctl_modify;
off_t gctl_mediasize;
char gctl_info[G_GATE_INFOSIZE];
char gctl_readprov[NAME_MAX];
off_t gctl_readoffset;
};
struct g_gate_ctl_destroy {
u_int gctl_version;
int gctl_unit;
int gctl_force;
char gctl_name[NAME_MAX];
};
struct g_gate_ctl_cancel {
u_int gctl_version;
int gctl_unit;
uintptr_t gctl_seq;
char gctl_name[NAME_MAX];
};
struct g_gate_ctl_io {
u_int gctl_version;
int gctl_unit;
uintptr_t gctl_seq;
u_int gctl_cmd;
off_t gctl_offset;
off_t gctl_length;
void *gctl_data;
int gctl_error;
};
#endif /* !_G_GATE_H_ */