1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2012 Alexander Motin <mav@FreeBSD.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <sys/param.h>
30#include <sys/bio.h>
31#include <sys/endian.h>
32#include <sys/kernel.h>
33#include <sys/kobj.h>
34#include <sys/limits.h>
35#include <sys/lock.h>
36#include <sys/malloc.h>
37#include <sys/mutex.h>
38#include <sys/sysctl.h>
39#include <sys/systm.h>
40#include <geom/geom.h>
41#include "geom/raid/g_raid.h"
42#include "g_raid_tr_if.h"
43
44static MALLOC_DEFINE(M_TR_RAID5, "tr_raid5_data", "GEOM_RAID RAID5 data");
45
46#define TR_RAID5_NONE 0
47#define TR_RAID5_REBUILD 1
48#define TR_RAID5_RESYNC 2
49
50#define TR_RAID5_F_DOING_SOME	0x1
51#define TR_RAID5_F_LOCKED	0x2
52#define TR_RAID5_F_ABORT	0x4
53
54struct g_raid_tr_raid5_object {
55	struct g_raid_tr_object	 trso_base;
56	int			 trso_starting;
57	int			 trso_stopping;
58	int			 trso_type;
59	int			 trso_recover_slabs; /* slabs before rest */
60	int			 trso_fair_io;
61	int			 trso_meta_update;
62	int			 trso_flags;
63	struct g_raid_subdisk	*trso_failed_sd; /* like per volume */
64	void			*trso_buffer;	 /* Buffer space */
65	struct bio		 trso_bio;
66};
67
68static g_raid_tr_taste_t g_raid_tr_taste_raid5;
69static g_raid_tr_event_t g_raid_tr_event_raid5;
70static g_raid_tr_start_t g_raid_tr_start_raid5;
71static g_raid_tr_stop_t g_raid_tr_stop_raid5;
72static g_raid_tr_iostart_t g_raid_tr_iostart_raid5;
73static g_raid_tr_iodone_t g_raid_tr_iodone_raid5;
74static g_raid_tr_kerneldump_t g_raid_tr_kerneldump_raid5;
75static g_raid_tr_locked_t g_raid_tr_locked_raid5;
76static g_raid_tr_free_t g_raid_tr_free_raid5;
77
78static kobj_method_t g_raid_tr_raid5_methods[] = {
79	KOBJMETHOD(g_raid_tr_taste,	g_raid_tr_taste_raid5),
80	KOBJMETHOD(g_raid_tr_event,	g_raid_tr_event_raid5),
81	KOBJMETHOD(g_raid_tr_start,	g_raid_tr_start_raid5),
82	KOBJMETHOD(g_raid_tr_stop,	g_raid_tr_stop_raid5),
83	KOBJMETHOD(g_raid_tr_iostart,	g_raid_tr_iostart_raid5),
84	KOBJMETHOD(g_raid_tr_iodone,	g_raid_tr_iodone_raid5),
85	KOBJMETHOD(g_raid_tr_kerneldump, g_raid_tr_kerneldump_raid5),
86	KOBJMETHOD(g_raid_tr_locked,	g_raid_tr_locked_raid5),
87	KOBJMETHOD(g_raid_tr_free,	g_raid_tr_free_raid5),
88	{ 0, 0 }
89};
90
91static struct g_raid_tr_class g_raid_tr_raid5_class = {
92	"RAID5",
93	g_raid_tr_raid5_methods,
94	sizeof(struct g_raid_tr_raid5_object),
95	.trc_enable = 1,
96	.trc_priority = 100
97};
98
99static int
100g_raid_tr_taste_raid5(struct g_raid_tr_object *tr, struct g_raid_volume *vol)
101{
102	struct g_raid_tr_raid5_object *trs;
103	u_int qual;
104
105	trs = (struct g_raid_tr_raid5_object *)tr;
106	qual = tr->tro_volume->v_raid_level_qualifier;
107	if (tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID4 &&
108	    (qual == G_RAID_VOLUME_RLQ_R4P0 ||
109	     qual == G_RAID_VOLUME_RLQ_R4PN)) {
110		/* RAID4 */
111	} else if ((tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID5 ||
112	     tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID5E ||
113	     tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID5EE ||
114	     tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID5R ||
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 == G_RAID_VOLUME_RLQ_R5RA ||
118	     qual == G_RAID_VOLUME_RLQ_R5RS ||
119	     qual == G_RAID_VOLUME_RLQ_R5LA ||
120	     qual == G_RAID_VOLUME_RLQ_R5LS)) {
121		/* RAID5/5E/5EE/5R/6/MDF */
122	} else
123		return (G_RAID_TR_TASTE_FAIL);
124	trs->trso_starting = 1;
125	return (G_RAID_TR_TASTE_SUCCEED);
126}
127
128static int
129g_raid_tr_update_state_raid5(struct g_raid_volume *vol,
130    struct g_raid_subdisk *sd)
131{
132	struct g_raid_tr_raid5_object *trs;
133	struct g_raid_softc *sc;
134	u_int s;
135	int na, ns, nu;
136
137	sc = vol->v_softc;
138	trs = (struct g_raid_tr_raid5_object *)vol->v_tr;
139	if (trs->trso_stopping &&
140	    (trs->trso_flags & TR_RAID5_F_DOING_SOME) == 0)
141		s = G_RAID_VOLUME_S_STOPPED;
142	else if (trs->trso_starting)
143		s = G_RAID_VOLUME_S_STARTING;
144	else {
145		na = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_ACTIVE);
146		ns = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_STALE) +
147		     g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_RESYNC);
148		nu = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_UNINITIALIZED);
149		if (na == vol->v_disks_count)
150			s = G_RAID_VOLUME_S_OPTIMAL;
151		else if (na + ns == vol->v_disks_count ||
152		    na + ns + nu == vol->v_disks_count /* XXX: Temporary. */)
153			s = G_RAID_VOLUME_S_SUBOPTIMAL;
154		else if (na == vol->v_disks_count - 1 ||
155		    na + ns + nu == vol->v_disks_count)
156			s = G_RAID_VOLUME_S_DEGRADED;
157		else
158			s = G_RAID_VOLUME_S_BROKEN;
159	}
160	if (s != vol->v_state) {
161		g_raid_event_send(vol, G_RAID_VOLUME_S_ALIVE(s) ?
162		    G_RAID_VOLUME_E_UP : G_RAID_VOLUME_E_DOWN,
163		    G_RAID_EVENT_VOLUME);
164		g_raid_change_volume_state(vol, s);
165		if (!trs->trso_starting && !trs->trso_stopping)
166			g_raid_write_metadata(sc, vol, NULL, NULL);
167	}
168	return (0);
169}
170
171static int
172g_raid_tr_event_raid5(struct g_raid_tr_object *tr,
173    struct g_raid_subdisk *sd, u_int event)
174{
175
176	g_raid_tr_update_state_raid5(tr->tro_volume, sd);
177	return (0);
178}
179
180static int
181g_raid_tr_start_raid5(struct g_raid_tr_object *tr)
182{
183	struct g_raid_tr_raid5_object *trs;
184	struct g_raid_volume *vol;
185
186	trs = (struct g_raid_tr_raid5_object *)tr;
187	trs->trso_starting = 0;
188	vol = tr->tro_volume;
189	vol->v_read_only = 1;
190	g_raid_tr_update_state_raid5(vol, NULL);
191	return (0);
192}
193
194static int
195g_raid_tr_stop_raid5(struct g_raid_tr_object *tr)
196{
197	struct g_raid_tr_raid5_object *trs;
198	struct g_raid_volume *vol;
199
200	trs = (struct g_raid_tr_raid5_object *)tr;
201	vol = tr->tro_volume;
202	trs->trso_starting = 0;
203	trs->trso_stopping = 1;
204	g_raid_tr_update_state_raid5(vol, NULL);
205	return (0);
206}
207
208static void
209g_raid_tr_iostart_raid5_read(struct g_raid_tr_object *tr, struct bio *bp)
210{
211	struct g_raid_volume *vol;
212	struct g_raid_subdisk *sd;
213	struct bio_queue_head queue;
214	struct bio *cbp;
215	char *addr;
216	off_t offset, start, length, nstripe, remain;
217	int no, pno, ddisks, pdisks, protate, pleft;
218	u_int strip_size, lvl, qual;
219
220	vol = tr->tro_volume;
221	addr = bp->bio_data;
222	strip_size = vol->v_strip_size;
223	lvl = tr->tro_volume->v_raid_level;
224	qual = tr->tro_volume->v_raid_level_qualifier;
225	protate = tr->tro_volume->v_rotate_parity;
226
227	/* Stripe number. */
228	nstripe = bp->bio_offset / strip_size;
229	/* Start position in stripe. */
230	start = bp->bio_offset % strip_size;
231	/* Number of data and parity disks. */
232	if (lvl == G_RAID_VOLUME_RL_RAIDMDF)
233		pdisks = tr->tro_volume->v_mdf_pdisks;
234	else if (lvl == G_RAID_VOLUME_RL_RAID5EE ||
235	    lvl == G_RAID_VOLUME_RL_RAID6)
236		pdisks = 2;
237	else
238		pdisks = 1;
239	ddisks = vol->v_disks_count - pdisks;
240	/* Parity disk number. */
241	if (lvl == G_RAID_VOLUME_RL_RAID4) {
242		if (qual == 0)		/* P0 */
243			pno = 0;
244		else			/* PN */
245			pno = ddisks;
246		pleft = -1;
247	} else {
248		pno = (nstripe / (ddisks * protate)) % vol->v_disks_count;
249		pleft = protate - (nstripe / ddisks) % protate;
250		if (qual >= 2) {	/* PN/Left */
251			pno = ddisks - pno;
252			if (pno < 0)
253				pno += vol->v_disks_count;
254		}
255	}
256	/* Data disk number. */
257	no = nstripe % ddisks;
258	if (lvl == G_RAID_VOLUME_RL_RAID4) {
259		if (qual == 0)
260			no += pdisks;
261	} else if (qual & 1) {	/* Continuation/Symmetric */
262		no = (pno + pdisks + no) % vol->v_disks_count;
263	} else if (no >= pno)	/* Restart/Asymmetric */
264		no += pdisks;
265	else
266		no += imax(0, pno + pdisks - vol->v_disks_count);
267	/* Stripe start position in disk. */
268	offset = (nstripe / ddisks) * strip_size;
269	/* Length of data to operate. */
270	remain = bp->bio_length;
271
272	bioq_init(&queue);
273	do {
274		length = MIN(strip_size - start, remain);
275		cbp = g_clone_bio(bp);
276		if (cbp == NULL)
277			goto failure;
278		cbp->bio_offset = offset + start;
279		cbp->bio_data = addr;
280		cbp->bio_length = length;
281		cbp->bio_caller1 = &vol->v_subdisks[no];
282		bioq_insert_tail(&queue, cbp);
283		no++;
284		if (lvl == G_RAID_VOLUME_RL_RAID4) {
285			no %= vol->v_disks_count;
286			if (no == pno)
287				no = (no + pdisks) % vol->v_disks_count;
288		} else if (qual & 1) {	/* Continuation/Symmetric */
289			no %= vol->v_disks_count;
290			if (no == pno) {
291				if ((--pleft) <= 0) {
292					pleft += protate;
293					if (qual < 2)	/* P0/Right */
294						pno++;
295					else		/* PN/Left */
296						pno += vol->v_disks_count - 1;
297					pno %= vol->v_disks_count;
298				}
299				no = (pno + pdisks) % vol->v_disks_count;
300				offset += strip_size;
301			}
302		} else {		/* Restart/Asymmetric */
303			if (no == pno)
304				no += pdisks;
305			if (no >= vol->v_disks_count) {
306				no -= vol->v_disks_count;
307				if ((--pleft) <= 0) {
308					pleft += protate;
309					if (qual < 2)	/* P0/Right */
310						pno++;
311					else		/* PN/Left */
312						pno += vol->v_disks_count - 1;
313					pno %= vol->v_disks_count;
314				}
315				if (no == pno)
316					no += pdisks;
317				else
318					no += imax(0, pno + pdisks - vol->v_disks_count);
319				offset += strip_size;
320			}
321		}
322		remain -= length;
323		addr += length;
324		start = 0;
325	} while (remain > 0);
326	while ((cbp = bioq_takefirst(&queue)) != NULL) {
327		sd = cbp->bio_caller1;
328		cbp->bio_caller1 = NULL;
329		g_raid_subdisk_iostart(sd, cbp);
330	}
331	return;
332failure:
333	while ((cbp = bioq_takefirst(&queue)) != NULL)
334		g_destroy_bio(cbp);
335	if (bp->bio_error == 0)
336		bp->bio_error = ENOMEM;
337	g_raid_iodone(bp, bp->bio_error);
338}
339
340static void
341g_raid_tr_iostart_raid5(struct g_raid_tr_object *tr, struct bio *bp)
342{
343	struct g_raid_volume *vol;
344
345	vol = tr->tro_volume;
346	if (vol->v_state < G_RAID_VOLUME_S_SUBOPTIMAL) {
347		g_raid_iodone(bp, EIO);
348		return;
349	}
350	switch (bp->bio_cmd) {
351	case BIO_READ:
352		g_raid_tr_iostart_raid5_read(tr, bp);
353		break;
354	case BIO_WRITE:
355	case BIO_DELETE:
356	case BIO_FLUSH:
357	case BIO_SPEEDUP:
358		g_raid_iodone(bp, ENODEV);
359		break;
360	default:
361		KASSERT(1 == 0, ("Invalid command here: %u (volume=%s)",
362		    bp->bio_cmd, vol->v_name));
363		break;
364	}
365}
366
367static void
368g_raid_tr_iodone_raid5(struct g_raid_tr_object *tr,
369    struct g_raid_subdisk *sd, struct bio *bp)
370{
371	struct bio *pbp;
372
373	pbp = bp->bio_parent;
374	if (pbp->bio_error == 0)
375		pbp->bio_error = bp->bio_error;
376	pbp->bio_inbed++;
377	g_destroy_bio(bp);
378	if (pbp->bio_children == pbp->bio_inbed) {
379		pbp->bio_completed = pbp->bio_length;
380		g_raid_iodone(pbp, pbp->bio_error);
381	}
382}
383
384static int
385g_raid_tr_kerneldump_raid5(struct g_raid_tr_object *tr, void *virtual,
386    off_t offset, size_t length)
387{
388
389	return (ENODEV);
390}
391
392static int
393g_raid_tr_locked_raid5(struct g_raid_tr_object *tr, void *argp)
394{
395	struct bio *bp;
396	struct g_raid_subdisk *sd;
397
398	bp = (struct bio *)argp;
399	sd = (struct g_raid_subdisk *)bp->bio_caller1;
400	g_raid_subdisk_iostart(sd, bp);
401
402	return (0);
403}
404
405static int
406g_raid_tr_free_raid5(struct g_raid_tr_object *tr)
407{
408	struct g_raid_tr_raid5_object *trs;
409
410	trs = (struct g_raid_tr_raid5_object *)tr;
411
412	if (trs->trso_buffer != NULL) {
413		free(trs->trso_buffer, M_TR_RAID5);
414		trs->trso_buffer = NULL;
415	}
416	return (0);
417}
418
419G_RAID_TR_DECLARE(raid5, "RAID5");
420