1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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/cdefs.h>
30__FBSDID("$FreeBSD$");
31
32#include <sys/param.h>
33#include <sys/bio.h>
34#include <sys/endian.h>
35#include <sys/kernel.h>
36#include <sys/kobj.h>
37#include <sys/limits.h>
38#include <sys/lock.h>
39#include <sys/malloc.h>
40#include <sys/mutex.h>
41#include <sys/sysctl.h>
42#include <sys/systm.h>
43#include <geom/geom.h>
44#include "geom/raid/g_raid.h"
45#include "g_raid_tr_if.h"
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_enable = 1,
99	.trc_priority = 100
100};
101
102static int
103g_raid_tr_taste_raid5(struct g_raid_tr_object *tr, struct g_raid_volume *vol)
104{
105	struct g_raid_tr_raid5_object *trs;
106	u_int qual;
107
108	trs = (struct g_raid_tr_raid5_object *)tr;
109	qual = tr->tro_volume->v_raid_level_qualifier;
110	if (tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID4 &&
111	    (qual == G_RAID_VOLUME_RLQ_R4P0 ||
112	     qual == G_RAID_VOLUME_RLQ_R4PN)) {
113		/* RAID4 */
114	} else if ((tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID5 ||
115	     tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID5E ||
116	     tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID5EE ||
117	     tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID5R ||
118	     tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID6 ||
119	     tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAIDMDF) &&
120	    (qual == G_RAID_VOLUME_RLQ_R5RA ||
121	     qual == G_RAID_VOLUME_RLQ_R5RS ||
122	     qual == G_RAID_VOLUME_RLQ_R5LA ||
123	     qual == G_RAID_VOLUME_RLQ_R5LS)) {
124		/* RAID5/5E/5EE/5R/6/MDF */
125	} else
126		return (G_RAID_TR_TASTE_FAIL);
127	trs->trso_starting = 1;
128	return (G_RAID_TR_TASTE_SUCCEED);
129}
130
131static int
132g_raid_tr_update_state_raid5(struct g_raid_volume *vol,
133    struct g_raid_subdisk *sd)
134{
135	struct g_raid_tr_raid5_object *trs;
136	struct g_raid_softc *sc;
137	u_int s;
138	int na, ns, nu;
139
140	sc = vol->v_softc;
141	trs = (struct g_raid_tr_raid5_object *)vol->v_tr;
142	if (trs->trso_stopping &&
143	    (trs->trso_flags & TR_RAID5_F_DOING_SOME) == 0)
144		s = G_RAID_VOLUME_S_STOPPED;
145	else if (trs->trso_starting)
146		s = G_RAID_VOLUME_S_STARTING;
147	else {
148		na = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_ACTIVE);
149		ns = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_STALE) +
150		     g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_RESYNC);
151		nu = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_UNINITIALIZED);
152		if (na == vol->v_disks_count)
153			s = G_RAID_VOLUME_S_OPTIMAL;
154		else if (na + ns == vol->v_disks_count ||
155		    na + ns + nu == vol->v_disks_count /* XXX: Temporary. */)
156			s = G_RAID_VOLUME_S_SUBOPTIMAL;
157		else if (na == vol->v_disks_count - 1 ||
158		    na + ns + nu == vol->v_disks_count)
159			s = G_RAID_VOLUME_S_DEGRADED;
160		else
161			s = G_RAID_VOLUME_S_BROKEN;
162	}
163	if (s != vol->v_state) {
164		g_raid_event_send(vol, G_RAID_VOLUME_S_ALIVE(s) ?
165		    G_RAID_VOLUME_E_UP : G_RAID_VOLUME_E_DOWN,
166		    G_RAID_EVENT_VOLUME);
167		g_raid_change_volume_state(vol, s);
168		if (!trs->trso_starting && !trs->trso_stopping)
169			g_raid_write_metadata(sc, vol, NULL, NULL);
170	}
171	return (0);
172}
173
174static int
175g_raid_tr_event_raid5(struct g_raid_tr_object *tr,
176    struct g_raid_subdisk *sd, u_int event)
177{
178
179	g_raid_tr_update_state_raid5(tr->tro_volume, sd);
180	return (0);
181}
182
183static int
184g_raid_tr_start_raid5(struct g_raid_tr_object *tr)
185{
186	struct g_raid_tr_raid5_object *trs;
187	struct g_raid_volume *vol;
188
189	trs = (struct g_raid_tr_raid5_object *)tr;
190	trs->trso_starting = 0;
191	vol = tr->tro_volume;
192	vol->v_read_only = 1;
193	g_raid_tr_update_state_raid5(vol, NULL);
194	return (0);
195}
196
197static int
198g_raid_tr_stop_raid5(struct g_raid_tr_object *tr)
199{
200	struct g_raid_tr_raid5_object *trs;
201	struct g_raid_volume *vol;
202
203	trs = (struct g_raid_tr_raid5_object *)tr;
204	vol = tr->tro_volume;
205	trs->trso_starting = 0;
206	trs->trso_stopping = 1;
207	g_raid_tr_update_state_raid5(vol, NULL);
208	return (0);
209}
210
211static void
212g_raid_tr_iostart_raid5_read(struct g_raid_tr_object *tr, struct bio *bp)
213{
214	struct g_raid_volume *vol;
215	struct g_raid_subdisk *sd;
216	struct bio_queue_head queue;
217	struct bio *cbp;
218	char *addr;
219	off_t offset, start, length, nstripe, remain;
220	int no, pno, ddisks, pdisks, protate, pleft;
221	u_int strip_size, lvl, qual;
222
223	vol = tr->tro_volume;
224	addr = bp->bio_data;
225	strip_size = vol->v_strip_size;
226	lvl = tr->tro_volume->v_raid_level;
227	qual = tr->tro_volume->v_raid_level_qualifier;
228	protate = tr->tro_volume->v_rotate_parity;
229
230	/* Stripe number. */
231	nstripe = bp->bio_offset / strip_size;
232	/* Start position in stripe. */
233	start = bp->bio_offset % strip_size;
234	/* Number of data and parity disks. */
235	if (lvl == G_RAID_VOLUME_RL_RAIDMDF)
236		pdisks = tr->tro_volume->v_mdf_pdisks;
237	else if (lvl == G_RAID_VOLUME_RL_RAID5EE ||
238	    lvl == G_RAID_VOLUME_RL_RAID6)
239		pdisks = 2;
240	else
241		pdisks = 1;
242	ddisks = vol->v_disks_count - pdisks;
243	/* Parity disk number. */
244	if (lvl == G_RAID_VOLUME_RL_RAID4) {
245		if (qual == 0)		/* P0 */
246			pno = 0;
247		else			/* PN */
248			pno = ddisks;
249		pleft = -1;
250	} else {
251		pno = (nstripe / (ddisks * protate)) % vol->v_disks_count;
252		pleft = protate - (nstripe / ddisks) % protate;
253		if (qual >= 2) {	/* PN/Left */
254			pno = ddisks - pno;
255			if (pno < 0)
256				pno += vol->v_disks_count;
257		}
258	}
259	/* Data disk number. */
260	no = nstripe % ddisks;
261	if (lvl == G_RAID_VOLUME_RL_RAID4) {
262		if (qual == 0)
263			no += pdisks;
264	} else if (qual & 1) {	/* Continuation/Symmetric */
265		no = (pno + pdisks + no) % vol->v_disks_count;
266	} else if (no >= pno)	/* Restart/Asymmetric */
267		no += pdisks;
268	else
269		no += imax(0, pno + pdisks - vol->v_disks_count);
270	/* Stripe start position in disk. */
271	offset = (nstripe / ddisks) * strip_size;
272	/* Length of data to operate. */
273	remain = bp->bio_length;
274
275	bioq_init(&queue);
276	do {
277		length = MIN(strip_size - start, remain);
278		cbp = g_clone_bio(bp);
279		if (cbp == NULL)
280			goto failure;
281		cbp->bio_offset = offset + start;
282		cbp->bio_data = addr;
283		cbp->bio_length = length;
284		cbp->bio_caller1 = &vol->v_subdisks[no];
285		bioq_insert_tail(&queue, cbp);
286		no++;
287		if (lvl == G_RAID_VOLUME_RL_RAID4) {
288			no %= vol->v_disks_count;
289			if (no == pno)
290				no = (no + pdisks) % vol->v_disks_count;
291		} else if (qual & 1) {	/* Continuation/Symmetric */
292			no %= vol->v_disks_count;
293			if (no == pno) {
294				if ((--pleft) <= 0) {
295					pleft += protate;
296					if (qual < 2)	/* P0/Right */
297						pno++;
298					else		/* PN/Left */
299						pno += vol->v_disks_count - 1;
300					pno %= vol->v_disks_count;
301				}
302				no = (pno + pdisks) % vol->v_disks_count;
303				offset += strip_size;
304			}
305		} else {		/* Restart/Asymmetric */
306			if (no == pno)
307				no += pdisks;
308			if (no >= vol->v_disks_count) {
309				no -= vol->v_disks_count;
310				if ((--pleft) <= 0) {
311					pleft += protate;
312					if (qual < 2)	/* P0/Right */
313						pno++;
314					else		/* PN/Left */
315						pno += vol->v_disks_count - 1;
316					pno %= vol->v_disks_count;
317				}
318				if (no == pno)
319					no += pdisks;
320				else
321					no += imax(0, pno + pdisks - vol->v_disks_count);
322				offset += strip_size;
323			}
324		}
325		remain -= length;
326		addr += length;
327		start = 0;
328	} while (remain > 0);
329	while ((cbp = bioq_takefirst(&queue)) != NULL) {
330		sd = cbp->bio_caller1;
331		cbp->bio_caller1 = NULL;
332		g_raid_subdisk_iostart(sd, cbp);
333	}
334	return;
335failure:
336	while ((cbp = bioq_takefirst(&queue)) != NULL)
337		g_destroy_bio(cbp);
338	if (bp->bio_error == 0)
339		bp->bio_error = ENOMEM;
340	g_raid_iodone(bp, bp->bio_error);
341}
342
343static void
344g_raid_tr_iostart_raid5(struct g_raid_tr_object *tr, struct bio *bp)
345{
346	struct g_raid_volume *vol;
347
348	vol = tr->tro_volume;
349	if (vol->v_state < G_RAID_VOLUME_S_SUBOPTIMAL) {
350		g_raid_iodone(bp, EIO);
351		return;
352	}
353	switch (bp->bio_cmd) {
354	case BIO_READ:
355		g_raid_tr_iostart_raid5_read(tr, bp);
356		break;
357	case BIO_WRITE:
358	case BIO_DELETE:
359	case BIO_FLUSH:
360	case BIO_SPEEDUP:
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
376	pbp = bp->bio_parent;
377	if (pbp->bio_error == 0)
378		pbp->bio_error = bp->bio_error;
379	pbp->bio_inbed++;
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, pbp->bio_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(raid5, "RAID5");
423