tr_raid5.c revision 234993 
1/*-
2 * Copyright (c) 2012 Alexander Motin <mav@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/geom/raid/tr_raid5.c 234993 2012-05-04 07:32:57Z mav $");
29
30#include <sys/param.h>
31#include <sys/bio.h>
32#include <sys/endian.h>
33#include <sys/kernel.h>
34#include <sys/kobj.h>
35#include <sys/limits.h>
36#include <sys/lock.h>
37#include <sys/malloc.h>
38#include <sys/mutex.h>
39#include <sys/sysctl.h>
40#include <sys/systm.h>
41#include <geom/geom.h>
42#include "geom/raid/g_raid.h"
43#include "g_raid_tr_if.h"
44
45SYSCTL_DECL(_kern_geom_raid);
46
47static MALLOC_DEFINE(M_TR_RAID5, "tr_raid5_data", "GEOM_RAID RAID5 data");
48
49#define TR_RAID5_NONE 0
50#define TR_RAID5_REBUILD 1
51#define TR_RAID5_RESYNC 2
52
53#define TR_RAID5_F_DOING_SOME	0x1
54#define TR_RAID5_F_LOCKED	0x2
55#define TR_RAID5_F_ABORT	0x4
56
57struct g_raid_tr_raid5_object {
58	struct g_raid_tr_object	 trso_base;
59	int			 trso_starting;
60	int			 trso_stopping;
61	int			 trso_type;
62	int			 trso_recover_slabs; /* slabs before rest */
63	int			 trso_fair_io;
64	int			 trso_meta_update;
65	int			 trso_flags;
66	struct g_raid_subdisk	*trso_failed_sd; /* like per volume */
67	void			*trso_buffer;	 /* Buffer space */
68	struct bio		 trso_bio;
69};
70
71static g_raid_tr_taste_t g_raid_tr_taste_raid5;
72static g_raid_tr_event_t g_raid_tr_event_raid5;
73static g_raid_tr_start_t g_raid_tr_start_raid5;
74static g_raid_tr_stop_t g_raid_tr_stop_raid5;
75static g_raid_tr_iostart_t g_raid_tr_iostart_raid5;
76static g_raid_tr_iodone_t g_raid_tr_iodone_raid5;
77static g_raid_tr_kerneldump_t g_raid_tr_kerneldump_raid5;
78static g_raid_tr_locked_t g_raid_tr_locked_raid5;
79static g_raid_tr_free_t g_raid_tr_free_raid5;
80
81static kobj_method_t g_raid_tr_raid5_methods[] = {
82	KOBJMETHOD(g_raid_tr_taste,	g_raid_tr_taste_raid5),
83	KOBJMETHOD(g_raid_tr_event,	g_raid_tr_event_raid5),
84	KOBJMETHOD(g_raid_tr_start,	g_raid_tr_start_raid5),
85	KOBJMETHOD(g_raid_tr_stop,	g_raid_tr_stop_raid5),
86	KOBJMETHOD(g_raid_tr_iostart,	g_raid_tr_iostart_raid5),
87	KOBJMETHOD(g_raid_tr_iodone,	g_raid_tr_iodone_raid5),
88	KOBJMETHOD(g_raid_tr_kerneldump, g_raid_tr_kerneldump_raid5),
89	KOBJMETHOD(g_raid_tr_locked,	g_raid_tr_locked_raid5),
90	KOBJMETHOD(g_raid_tr_free,	g_raid_tr_free_raid5),
91	{ 0, 0 }
92};
93
94static struct g_raid_tr_class g_raid_tr_raid5_class = {
95	"RAID5",
96	g_raid_tr_raid5_methods,
97	sizeof(struct g_raid_tr_raid5_object),
98	.trc_priority = 100
99};
100
101static int
102g_raid_tr_taste_raid5(struct g_raid_tr_object *tr, struct g_raid_volume *vol)
103{
104	struct g_raid_tr_raid5_object *trs;
105	u_int qual;
106
107	trs = (struct g_raid_tr_raid5_object *)tr;
108	qual = tr->tro_volume->v_raid_level_qualifier;
109	if (tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID4 &&
110	    qual >= 0 && qual <= 1) {
111		/* RAID4 */
112	} else if ((tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID5 ||
113	     tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID5E ||
114	     tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID5EE ||
115	     tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID6 ||
116	     tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAIDMDF) &&
117	    qual >= 0 && qual <= 3) {
118		/* RAID5/5E/5EE/6/MDF */
119	} else
120		return (G_RAID_TR_TASTE_FAIL);
121	trs->trso_starting = 1;
122	return (G_RAID_TR_TASTE_SUCCEED);
123}
124
125static int
126g_raid_tr_update_state_raid5(struct g_raid_volume *vol,
127    struct g_raid_subdisk *sd)
128{
129	struct g_raid_tr_raid5_object *trs;
130	struct g_raid_softc *sc;
131	u_int s;
132	int na, ns, nu;
133
134	sc = vol->v_softc;
135	trs = (struct g_raid_tr_raid5_object *)vol->v_tr;
136	if (trs->trso_stopping &&
137	    (trs->trso_flags & TR_RAID5_F_DOING_SOME) == 0)
138		s = G_RAID_VOLUME_S_STOPPED;
139	else if (trs->trso_starting)
140		s = G_RAID_VOLUME_S_STARTING;
141	else {
142		na = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_ACTIVE);
143		ns = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_STALE) +
144		     g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_RESYNC);
145		nu = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_UNINITIALIZED);
146		if (na == vol->v_disks_count)
147			s = G_RAID_VOLUME_S_OPTIMAL;
148		else if (na + ns == vol->v_disks_count ||
149		    na + ns + nu == vol->v_disks_count /* XXX: Temporary. */)
150			s = G_RAID_VOLUME_S_SUBOPTIMAL;
151		else if (na == vol->v_disks_count - 1 ||
152		    na + ns + nu == vol->v_disks_count)
153			s = G_RAID_VOLUME_S_DEGRADED;
154		else
155			s = G_RAID_VOLUME_S_BROKEN;
156	}
157	if (s != vol->v_state) {
158		g_raid_event_send(vol, G_RAID_VOLUME_S_ALIVE(s) ?
159		    G_RAID_VOLUME_E_UP : G_RAID_VOLUME_E_DOWN,
160		    G_RAID_EVENT_VOLUME);
161		g_raid_change_volume_state(vol, s);
162		if (!trs->trso_starting && !trs->trso_stopping)
163			g_raid_write_metadata(sc, vol, NULL, NULL);
164	}
165	return (0);
166}
167
168static int
169g_raid_tr_event_raid5(struct g_raid_tr_object *tr,
170    struct g_raid_subdisk *sd, u_int event)
171{
172
173	g_raid_tr_update_state_raid5(tr->tro_volume, sd);
174	return (0);
175}
176
177static int
178g_raid_tr_start_raid5(struct g_raid_tr_object *tr)
179{
180	struct g_raid_tr_raid5_object *trs;
181	struct g_raid_volume *vol;
182
183	trs = (struct g_raid_tr_raid5_object *)tr;
184	vol = tr->tro_volume;
185	trs->trso_starting = 0;
186	g_raid_tr_update_state_raid5(vol, NULL);
187	return (0);
188}
189
190static int
191g_raid_tr_stop_raid5(struct g_raid_tr_object *tr)
192{
193	struct g_raid_tr_raid5_object *trs;
194	struct g_raid_volume *vol;
195
196	trs = (struct g_raid_tr_raid5_object *)tr;
197	vol = tr->tro_volume;
198	trs->trso_starting = 0;
199	trs->trso_stopping = 1;
200	g_raid_tr_update_state_raid5(vol, NULL);
201	return (0);
202}
203
204static void
205g_raid_tr_iostart_raid5_read(struct g_raid_tr_object *tr, struct bio *bp)
206{
207	struct g_raid_volume *vol;
208	struct g_raid_subdisk *sd;
209	struct bio_queue_head queue;
210	struct bio *cbp;
211	char *addr;
212	off_t offset, start, length, nstripe, remain;
213	int no, pno, ddisks, pdisks;
214	u_int strip_size, lvl, qual;
215
216	vol = tr->tro_volume;
217	addr = bp->bio_data;
218	strip_size = vol->v_strip_size;
219	lvl = tr->tro_volume->v_raid_level;
220	qual = tr->tro_volume->v_raid_level_qualifier;
221
222	/* Stripe number. */
223	nstripe = bp->bio_offset / strip_size;
224	/* Start position in stripe. */
225	start = bp->bio_offset % strip_size;
226	/* Number of data and parity disks. */
227	if (lvl == G_RAID_VOLUME_RL_RAIDMDF)
228		pdisks = 3;
229	else if (lvl == G_RAID_VOLUME_RL_RAID5EE ||
230	    lvl == G_RAID_VOLUME_RL_RAID6)
231		pdisks = 2;
232	else
233		pdisks = 1;
234	ddisks = vol->v_disks_count - pdisks;
235	/* Parity disk number. */
236	if (lvl == G_RAID_VOLUME_RL_RAID4) {
237		if (qual == 0)		/* P0 */
238			pno = 0;
239		else			/* PN */
240			pno = ddisks;
241	} else {
242		pno = (nstripe / ddisks) % vol->v_disks_count;
243		if (qual >= 2) {	/* PN/Left */
244			pno = ddisks - pno;
245			if (pno < 0)
246				pno += vol->v_disks_count;
247		}
248	}
249	/* Data disk number. */
250	no = nstripe % ddisks;
251	if (lvl == G_RAID_VOLUME_RL_RAID4) {
252		if (qual == 0)
253			no += pdisks;
254	} else if (qual & 1) {	/* Continuation/Symmetric */
255		no = (pno + pdisks + no) % vol->v_disks_count;
256	} else if (no >= pno)	/* Restart/Asymmetric */
257		no += pdisks;
258	else
259		no += imax(0, pno + pdisks - vol->v_disks_count);
260	/* Stripe start position in disk. */
261	offset = (nstripe / ddisks) * strip_size;
262	/* Length of data to operate. */
263	remain = bp->bio_length;
264
265	bioq_init(&queue);
266	do {
267		length = MIN(strip_size - start, remain);
268		cbp = g_clone_bio(bp);
269		if (cbp == NULL)
270			goto failure;
271		cbp->bio_offset = offset + start;
272		cbp->bio_data = addr;
273		cbp->bio_length = length;
274		cbp->bio_caller1 = &vol->v_subdisks[no];
275		bioq_insert_tail(&queue, cbp);
276		no++;
277		if (lvl == G_RAID_VOLUME_RL_RAID4) {
278			no %= vol->v_disks_count;
279			if (no == pno)
280				no = (no + pdisks) % vol->v_disks_count;
281		} else if (qual & 1) {	/* Continuation/Symmetric */
282			no %= vol->v_disks_count;
283			if (no == pno) {
284				if (qual < 2)	/* P0/Right */
285					pno++;
286				else		/* PN/Left */
287					pno += vol->v_disks_count - 1;
288				pno %= vol->v_disks_count;
289				no = (pno + pdisks) % vol->v_disks_count;
290				offset += strip_size;
291			}
292		} else {		/* Restart/Asymmetric */
293			if (no == pno)
294				no += pdisks;
295			if (no >= vol->v_disks_count) {
296				no -= vol->v_disks_count;
297				if (qual < 2)	/* P0/Right */
298					pno++;
299				else		/* PN/Left */
300					pno += vol->v_disks_count - 1;
301				pno %= vol->v_disks_count;
302				if (no == pno)
303					no += pdisks;
304				else
305					no += imax(0, pno + pdisks - vol->v_disks_count);
306				offset += strip_size;
307			}
308		}
309		remain -= length;
310		addr += length;
311		start = 0;
312	} while (remain > 0);
313	for (cbp = bioq_first(&queue); cbp != NULL;
314	    cbp = bioq_first(&queue)) {
315		bioq_remove(&queue, cbp);
316		sd = cbp->bio_caller1;
317		cbp->bio_caller1 = NULL;
318		g_raid_subdisk_iostart(sd, cbp);
319	}
320	return;
321failure:
322	for (cbp = bioq_first(&queue); cbp != NULL;
323	    cbp = bioq_first(&queue)) {
324		bioq_remove(&queue, cbp);
325		g_destroy_bio(cbp);
326	}
327	if (bp->bio_error == 0)
328		bp->bio_error = ENOMEM;
329	g_raid_iodone(bp, bp->bio_error);
330}
331
332static void
333g_raid_tr_iostart_raid5(struct g_raid_tr_object *tr, struct bio *bp)
334{
335	struct g_raid_volume *vol;
336	struct g_raid_tr_raid5_object *trs;
337
338	vol = tr->tro_volume;
339	trs = (struct g_raid_tr_raid5_object *)tr;
340	if (vol->v_state < G_RAID_VOLUME_S_SUBOPTIMAL) {
341		g_raid_iodone(bp, EIO);
342		return;
343	}
344	switch (bp->bio_cmd) {
345	case BIO_READ:
346		g_raid_tr_iostart_raid5_read(tr, bp);
347		break;
348	case BIO_WRITE:
349	case BIO_DELETE:
350	case BIO_FLUSH:
351		g_raid_iodone(bp, ENODEV);
352		break;
353	default:
354		KASSERT(1 == 0, ("Invalid command here: %u (volume=%s)",
355		    bp->bio_cmd, vol->v_name));
356		break;
357	}
358}
359
360static void
361g_raid_tr_iodone_raid5(struct g_raid_tr_object *tr,
362    struct g_raid_subdisk *sd, struct bio *bp)
363{
364	struct bio *pbp;
365	int error;
366
367	pbp = bp->bio_parent;
368	pbp->bio_inbed++;
369	error = bp->bio_error;
370	g_destroy_bio(bp);
371	if (pbp->bio_children == pbp->bio_inbed) {
372		pbp->bio_completed = pbp->bio_length;
373		g_raid_iodone(pbp, error);
374	}
375}
376
377static int
378g_raid_tr_kerneldump_raid5(struct g_raid_tr_object *tr,
379    void *virtual, vm_offset_t physical, off_t offset, size_t length)
380{
381
382	return (ENODEV);
383}
384
385static int
386g_raid_tr_locked_raid5(struct g_raid_tr_object *tr, void *argp)
387{
388	struct bio *bp;
389	struct g_raid_subdisk *sd;
390
391	bp = (struct bio *)argp;
392	sd = (struct g_raid_subdisk *)bp->bio_caller1;
393	g_raid_subdisk_iostart(sd, bp);
394
395	return (0);
396}
397
398static int
399g_raid_tr_free_raid5(struct g_raid_tr_object *tr)
400{
401	struct g_raid_tr_raid5_object *trs;
402
403	trs = (struct g_raid_tr_raid5_object *)tr;
404
405	if (trs->trso_buffer != NULL) {
406		free(trs->trso_buffer, M_TR_RAID5);
407		trs->trso_buffer = NULL;
408	}
409	return (0);
410}
411
412G_RAID_TR_DECLARE(g_raid_tr_raid5);
413