tr_raid5.c revision 235076 
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 235076 2012-05-06 11:32:36Z 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_RAID5R ||
116	     tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID6 ||
117	     tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAIDMDF) &&
118	    qual >= 0 && qual <= 3) {
119		/* RAID5/5E/5EE/5R/6/MDF */
120	} else
121		return (G_RAID_TR_TASTE_FAIL);
122	trs->trso_starting = 1;
123	return (G_RAID_TR_TASTE_SUCCEED);
124}
125
126static int
127g_raid_tr_update_state_raid5(struct g_raid_volume *vol,
128    struct g_raid_subdisk *sd)
129{
130	struct g_raid_tr_raid5_object *trs;
131	struct g_raid_softc *sc;
132	u_int s;
133	int na, ns, nu;
134
135	sc = vol->v_softc;
136	trs = (struct g_raid_tr_raid5_object *)vol->v_tr;
137	if (trs->trso_stopping &&
138	    (trs->trso_flags & TR_RAID5_F_DOING_SOME) == 0)
139		s = G_RAID_VOLUME_S_STOPPED;
140	else if (trs->trso_starting)
141		s = G_RAID_VOLUME_S_STARTING;
142	else {
143		na = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_ACTIVE);
144		ns = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_STALE) +
145		     g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_RESYNC);
146		nu = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_UNINITIALIZED);
147		if (na == vol->v_disks_count)
148			s = G_RAID_VOLUME_S_OPTIMAL;
149		else if (na + ns == vol->v_disks_count ||
150		    na + ns + nu == vol->v_disks_count /* XXX: Temporary. */)
151			s = G_RAID_VOLUME_S_SUBOPTIMAL;
152		else if (na == vol->v_disks_count - 1 ||
153		    na + ns + nu == vol->v_disks_count)
154			s = G_RAID_VOLUME_S_DEGRADED;
155		else
156			s = G_RAID_VOLUME_S_BROKEN;
157	}
158	if (s != vol->v_state) {
159		g_raid_event_send(vol, G_RAID_VOLUME_S_ALIVE(s) ?
160		    G_RAID_VOLUME_E_UP : G_RAID_VOLUME_E_DOWN,
161		    G_RAID_EVENT_VOLUME);
162		g_raid_change_volume_state(vol, s);
163		if (!trs->trso_starting && !trs->trso_stopping)
164			g_raid_write_metadata(sc, vol, NULL, NULL);
165	}
166	return (0);
167}
168
169static int
170g_raid_tr_event_raid5(struct g_raid_tr_object *tr,
171    struct g_raid_subdisk *sd, u_int event)
172{
173
174	g_raid_tr_update_state_raid5(tr->tro_volume, sd);
175	return (0);
176}
177
178static int
179g_raid_tr_start_raid5(struct g_raid_tr_object *tr)
180{
181	struct g_raid_tr_raid5_object *trs;
182	struct g_raid_volume *vol;
183
184	trs = (struct g_raid_tr_raid5_object *)tr;
185	vol = tr->tro_volume;
186	trs->trso_starting = 0;
187	g_raid_tr_update_state_raid5(vol, NULL);
188	return (0);
189}
190
191static int
192g_raid_tr_stop_raid5(struct g_raid_tr_object *tr)
193{
194	struct g_raid_tr_raid5_object *trs;
195	struct g_raid_volume *vol;
196
197	trs = (struct g_raid_tr_raid5_object *)tr;
198	vol = tr->tro_volume;
199	trs->trso_starting = 0;
200	trs->trso_stopping = 1;
201	g_raid_tr_update_state_raid5(vol, NULL);
202	return (0);
203}
204
205static void
206g_raid_tr_iostart_raid5_read(struct g_raid_tr_object *tr, struct bio *bp)
207{
208	struct g_raid_volume *vol;
209	struct g_raid_subdisk *sd;
210	struct bio_queue_head queue;
211	struct bio *cbp;
212	char *addr;
213	off_t offset, start, length, nstripe, remain;
214	int no, pno, ddisks, pdisks, protate, pleft;
215	u_int strip_size, lvl, qual;
216
217	vol = tr->tro_volume;
218	addr = bp->bio_data;
219	strip_size = vol->v_strip_size;
220	lvl = tr->tro_volume->v_raid_level;
221	qual = tr->tro_volume->v_raid_level_qualifier;
222	protate = tr->tro_volume->v_rotate_parity;
223
224	/* Stripe number. */
225	nstripe = bp->bio_offset / strip_size;
226	/* Start position in stripe. */
227	start = bp->bio_offset % strip_size;
228	/* Number of data and parity disks. */
229	if (lvl == G_RAID_VOLUME_RL_RAIDMDF)
230		pdisks = tr->tro_volume->v_mdf_pdisks;
231	else if (lvl == G_RAID_VOLUME_RL_RAID5EE ||
232	    lvl == G_RAID_VOLUME_RL_RAID6)
233		pdisks = 2;
234	else
235		pdisks = 1;
236	ddisks = vol->v_disks_count - pdisks;
237	/* Parity disk number. */
238	if (lvl == G_RAID_VOLUME_RL_RAID4) {
239		if (qual == 0)		/* P0 */
240			pno = 0;
241		else			/* PN */
242			pno = ddisks;
243		pleft = -1;
244	} else {
245		pno = (nstripe / (ddisks * protate)) % vol->v_disks_count;
246		pleft = protate - (nstripe / ddisks) % protate;
247		if (qual >= 2) {	/* PN/Left */
248			pno = ddisks - pno;
249			if (pno < 0)
250				pno += vol->v_disks_count;
251		}
252	}
253	/* Data disk number. */
254	no = nstripe % ddisks;
255	if (lvl == G_RAID_VOLUME_RL_RAID4) {
256		if (qual == 0)
257			no += pdisks;
258	} else if (qual & 1) {	/* Continuation/Symmetric */
259		no = (pno + pdisks + no) % vol->v_disks_count;
260	} else if (no >= pno)	/* Restart/Asymmetric */
261		no += pdisks;
262	else
263		no += imax(0, pno + pdisks - vol->v_disks_count);
264	/* Stripe start position in disk. */
265	offset = (nstripe / ddisks) * strip_size;
266	/* Length of data to operate. */
267	remain = bp->bio_length;
268
269	bioq_init(&queue);
270	do {
271		length = MIN(strip_size - start, remain);
272		cbp = g_clone_bio(bp);
273		if (cbp == NULL)
274			goto failure;
275		cbp->bio_offset = offset + start;
276		cbp->bio_data = addr;
277		cbp->bio_length = length;
278		cbp->bio_caller1 = &vol->v_subdisks[no];
279		bioq_insert_tail(&queue, cbp);
280		no++;
281		if (lvl == G_RAID_VOLUME_RL_RAID4) {
282			no %= vol->v_disks_count;
283			if (no == pno)
284				no = (no + pdisks) % vol->v_disks_count;
285		} else if (qual & 1) {	/* Continuation/Symmetric */
286			no %= vol->v_disks_count;
287			if (no == pno) {
288				if ((--pleft) <= 0) {
289					pleft += protate;
290					if (qual < 2)	/* P0/Right */
291						pno++;
292					else		/* PN/Left */
293						pno += vol->v_disks_count - 1;
294					pno %= vol->v_disks_count;
295				}
296				no = (pno + pdisks) % vol->v_disks_count;
297				offset += strip_size;
298			}
299		} else {		/* Restart/Asymmetric */
300			if (no == pno)
301				no += pdisks;
302			if (no >= vol->v_disks_count) {
303				no -= vol->v_disks_count;
304				if ((--pleft) <= 0) {
305					pleft += protate;
306					if (qual < 2)	/* P0/Right */
307						pno++;
308					else		/* PN/Left */
309						pno += vol->v_disks_count - 1;
310					pno %= vol->v_disks_count;
311				}
312				if (no == pno)
313					no += pdisks;
314				else
315					no += imax(0, pno + pdisks - vol->v_disks_count);
316				offset += strip_size;
317			}
318		}
319		remain -= length;
320		addr += length;
321		start = 0;
322	} while (remain > 0);
323	for (cbp = bioq_first(&queue); cbp != NULL;
324	    cbp = bioq_first(&queue)) {
325		bioq_remove(&queue, cbp);
326		sd = cbp->bio_caller1;
327		cbp->bio_caller1 = NULL;
328		g_raid_subdisk_iostart(sd, cbp);
329	}
330	return;
331failure:
332	for (cbp = bioq_first(&queue); cbp != NULL;
333	    cbp = bioq_first(&queue)) {
334		bioq_remove(&queue, cbp);
335		g_destroy_bio(cbp);
336	}
337	if (bp->bio_error == 0)
338		bp->bio_error = ENOMEM;
339	g_raid_iodone(bp, bp->bio_error);
340}
341
342static void
343g_raid_tr_iostart_raid5(struct g_raid_tr_object *tr, struct bio *bp)
344{
345	struct g_raid_volume *vol;
346	struct g_raid_tr_raid5_object *trs;
347
348	vol = tr->tro_volume;
349	trs = (struct g_raid_tr_raid5_object *)tr;
350	if (vol->v_state < G_RAID_VOLUME_S_SUBOPTIMAL) {
351		g_raid_iodone(bp, EIO);
352		return;
353	}
354	switch (bp->bio_cmd) {
355	case BIO_READ:
356		g_raid_tr_iostart_raid5_read(tr, bp);
357		break;
358	case BIO_WRITE:
359	case BIO_DELETE:
360	case BIO_FLUSH:
361		g_raid_iodone(bp, ENODEV);
362		break;
363	default:
364		KASSERT(1 == 0, ("Invalid command here: %u (volume=%s)",
365		    bp->bio_cmd, vol->v_name));
366		break;
367	}
368}
369
370static void
371g_raid_tr_iodone_raid5(struct g_raid_tr_object *tr,
372    struct g_raid_subdisk *sd, struct bio *bp)
373{
374	struct bio *pbp;
375	int error;
376
377	pbp = bp->bio_parent;
378	pbp->bio_inbed++;
379	error = bp->bio_error;
380	g_destroy_bio(bp);
381	if (pbp->bio_children == pbp->bio_inbed) {
382		pbp->bio_completed = pbp->bio_length;
383		g_raid_iodone(pbp, error);
384	}
385}
386
387static int
388g_raid_tr_kerneldump_raid5(struct g_raid_tr_object *tr,
389    void *virtual, vm_offset_t physical, off_t offset, size_t length)
390{
391
392	return (ENODEV);
393}
394
395static int
396g_raid_tr_locked_raid5(struct g_raid_tr_object *tr, void *argp)
397{
398	struct bio *bp;
399	struct g_raid_subdisk *sd;
400
401	bp = (struct bio *)argp;
402	sd = (struct g_raid_subdisk *)bp->bio_caller1;
403	g_raid_subdisk_iostart(sd, bp);
404
405	return (0);
406}
407
408static int
409g_raid_tr_free_raid5(struct g_raid_tr_object *tr)
410{
411	struct g_raid_tr_raid5_object *trs;
412
413	trs = (struct g_raid_tr_raid5_object *)tr;
414
415	if (trs->trso_buffer != NULL) {
416		free(trs->trso_buffer, M_TR_RAID5);
417		trs->trso_buffer = NULL;
418	}
419	return (0);
420}
421
422G_RAID_TR_DECLARE(g_raid_tr_raid5);
423