summaryrefslogtreecommitdiffstats
path: root/sys/geom/geom_kern.c
blob: a346b6a0d8f108f64b11eb3029955b75f3169e89 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
/*-
 * Copyright (c) 2002 Poul-Henning Kamp
 * Copyright (c) 2002 Networks Associates Technology, Inc.
 * 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.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/eventhandler.h>
#include <sys/malloc.h>
#include <sys/bio.h>
#include <sys/sysctl.h>
#include <sys/proc.h>
#include <sys/kthread.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/sx.h>
#include <sys/sbuf.h>
#include <geom/geom.h>
#include <geom/geom_int.h>

MALLOC_DEFINE(M_GEOM, "GEOM", "Geom data structures");

struct sx topology_lock;

static struct proc *g_up_proc;

int g_debugflags;
int g_collectstats = 1;
int g_shutdown;

/*
 * G_UP and G_DOWN are the two threads which push I/O through the
 * stack.
 *
 * Things are procesed in a FIFO order, but these threads could be
 * part of I/O prioritization by deciding which bios/bioqs to service
 * in what order.
 *
 * We have only one thread in each direction, it is belived that until
 * a very non-trivial workload in the UP/DOWN path this will be enough,
 * but more than one can actually be run without problems.
 *
 * Holding the "mymutex" is a debugging feature:  It prevents people
 * from sleeping in the UP/DOWN I/O path by mistake or design (doing
 * so almost invariably result in deadlocks since it stalls all I/O
 * processing in the given direction.
 */

static void
g_up_procbody(void)
{
	struct proc *p = g_up_proc;
	struct thread *tp = FIRST_THREAD_IN_PROC(p);

	mtx_assert(&Giant, MA_NOTOWNED);
	tp->td_base_pri = PRIBIO;
	for(;;) {
		g_io_schedule_up(tp);
	}
}

struct kproc_desc g_up_kp = {
	"g_up",
	g_up_procbody,
	&g_up_proc,
};

static struct proc *g_down_proc;

static void
g_down_procbody(void)
{
	struct proc *p = g_down_proc;
	struct thread *tp = FIRST_THREAD_IN_PROC(p);

	mtx_assert(&Giant, MA_NOTOWNED);
	tp->td_base_pri = PRIBIO;
	for(;;) {
		g_io_schedule_down(tp);
	}
}

struct kproc_desc g_down_kp = {
	"g_down",
	g_down_procbody,
	&g_down_proc,
};

static struct proc *g_event_proc;

static void
g_event_procbody(void)
{
	struct proc *p = g_event_proc;
	struct thread *tp = FIRST_THREAD_IN_PROC(p);

	mtx_assert(&Giant, MA_NOTOWNED);
	tp->td_base_pri = PRIBIO;
	for(;;) {
		g_run_events();
		tsleep(&g_wait_event, PRIBIO, "-", hz/10);
	}
}

static struct kproc_desc g_event_kp = {
	"g_event",
	g_event_procbody,
	&g_event_proc,
};

static void
geom_shutdown(void *foo __unused)
{

	g_shutdown = 1;
}

void
g_init(void)
{

	g_trace(G_T_TOPOLOGY, "g_ignition");
	sx_init(&topology_lock, "GEOM topology");
	g_io_init();
	g_event_init();
	g_ctl_init();
	mtx_lock(&Giant);
	kproc_start(&g_event_kp);
	kproc_start(&g_up_kp);
	kproc_start(&g_down_kp);
	mtx_unlock(&Giant);
	EVENTHANDLER_REGISTER(shutdown_pre_sync, geom_shutdown, NULL,
		SHUTDOWN_PRI_FIRST);
}

static int
sysctl_kern_geom_conftxt(SYSCTL_HANDLER_ARGS)
{
	int error;
	struct sbuf *sb;

	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
	g_waitfor_event(g_conftxt, sb, M_WAITOK, NULL);
	error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
	sbuf_delete(sb);
	return error;
}
 
static int
sysctl_kern_geom_confdot(SYSCTL_HANDLER_ARGS)
{
	int error;
	struct sbuf *sb;

	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
	g_waitfor_event(g_confdot, sb, M_WAITOK, NULL);
	error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
	sbuf_delete(sb);
	return error;
}
 
static int
sysctl_kern_geom_confxml(SYSCTL_HANDLER_ARGS)
{
	int error;
	struct sbuf *sb;

	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
	g_waitfor_event(g_confxml, sb, M_WAITOK, NULL);
	error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
	sbuf_delete(sb);
	return error;
}

SYSCTL_NODE(_kern, OID_AUTO, geom, CTLFLAG_RW, 0, "GEOMetry management");

SYSCTL_PROC(_kern_geom, OID_AUTO, confxml, CTLTYPE_STRING|CTLFLAG_RD,
	0, 0, sysctl_kern_geom_confxml, "",
	"Dump the GEOM config in XML");

SYSCTL_PROC(_kern_geom, OID_AUTO, confdot, CTLTYPE_STRING|CTLFLAG_RD,
	0, 0, sysctl_kern_geom_confdot, "",
	"Dump the GEOM config in dot");

SYSCTL_PROC(_kern_geom, OID_AUTO, conftxt, CTLTYPE_STRING|CTLFLAG_RD,
	0, 0, sysctl_kern_geom_conftxt, "",
	"Dump the GEOM config in txt");

SYSCTL_INT(_kern_geom, OID_AUTO, debugflags, CTLFLAG_RW,
	&g_debugflags, 0, "");

SYSCTL_INT(_kern_geom, OID_AUTO, collectstats, CTLFLAG_RW,
	&g_collectstats, 0, "");

SYSCTL_INT(_debug_sizeof, OID_AUTO, g_class, CTLFLAG_RD,
	0, sizeof(struct g_class), "");
SYSCTL_INT(_debug_sizeof, OID_AUTO, g_geom, CTLFLAG_RD,
	0, sizeof(struct g_geom), "");
SYSCTL_INT(_debug_sizeof, OID_AUTO, g_provider, CTLFLAG_RD,
	0, sizeof(struct g_provider), "");
SYSCTL_INT(_debug_sizeof, OID_AUTO, g_consumer, CTLFLAG_RD,
	0, sizeof(struct g_consumer), "");
SYSCTL_INT(_debug_sizeof, OID_AUTO, g_bioq, CTLFLAG_RD,
	0, sizeof(struct g_bioq), "");
OpenPOWER on IntegriCloud