xref: /freebsd/sys/geom/raid/tr_raid5.c (revision a0ee8cc6)
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("$FreeBSD$");
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 
45 static MALLOC_DEFINE(M_TR_RAID5, "tr_raid5_data", "GEOM_RAID RAID5 data");
46 
47 #define TR_RAID5_NONE 0
48 #define TR_RAID5_REBUILD 1
49 #define TR_RAID5_RESYNC 2
50 
51 #define TR_RAID5_F_DOING_SOME	0x1
52 #define TR_RAID5_F_LOCKED	0x2
53 #define TR_RAID5_F_ABORT	0x4
54 
55 struct g_raid_tr_raid5_object {
56 	struct g_raid_tr_object	 trso_base;
57 	int			 trso_starting;
58 	int			 trso_stopping;
59 	int			 trso_type;
60 	int			 trso_recover_slabs; /* slabs before rest */
61 	int			 trso_fair_io;
62 	int			 trso_meta_update;
63 	int			 trso_flags;
64 	struct g_raid_subdisk	*trso_failed_sd; /* like per volume */
65 	void			*trso_buffer;	 /* Buffer space */
66 	struct bio		 trso_bio;
67 };
68 
69 static g_raid_tr_taste_t g_raid_tr_taste_raid5;
70 static g_raid_tr_event_t g_raid_tr_event_raid5;
71 static g_raid_tr_start_t g_raid_tr_start_raid5;
72 static g_raid_tr_stop_t g_raid_tr_stop_raid5;
73 static g_raid_tr_iostart_t g_raid_tr_iostart_raid5;
74 static g_raid_tr_iodone_t g_raid_tr_iodone_raid5;
75 static g_raid_tr_kerneldump_t g_raid_tr_kerneldump_raid5;
76 static g_raid_tr_locked_t g_raid_tr_locked_raid5;
77 static g_raid_tr_free_t g_raid_tr_free_raid5;
78 
79 static kobj_method_t g_raid_tr_raid5_methods[] = {
80 	KOBJMETHOD(g_raid_tr_taste,	g_raid_tr_taste_raid5),
81 	KOBJMETHOD(g_raid_tr_event,	g_raid_tr_event_raid5),
82 	KOBJMETHOD(g_raid_tr_start,	g_raid_tr_start_raid5),
83 	KOBJMETHOD(g_raid_tr_stop,	g_raid_tr_stop_raid5),
84 	KOBJMETHOD(g_raid_tr_iostart,	g_raid_tr_iostart_raid5),
85 	KOBJMETHOD(g_raid_tr_iodone,	g_raid_tr_iodone_raid5),
86 	KOBJMETHOD(g_raid_tr_kerneldump, g_raid_tr_kerneldump_raid5),
87 	KOBJMETHOD(g_raid_tr_locked,	g_raid_tr_locked_raid5),
88 	KOBJMETHOD(g_raid_tr_free,	g_raid_tr_free_raid5),
89 	{ 0, 0 }
90 };
91 
92 static struct g_raid_tr_class g_raid_tr_raid5_class = {
93 	"RAID5",
94 	g_raid_tr_raid5_methods,
95 	sizeof(struct g_raid_tr_raid5_object),
96 	.trc_enable = 1,
97 	.trc_priority = 100
98 };
99 
100 static int
101 g_raid_tr_taste_raid5(struct g_raid_tr_object *tr, struct g_raid_volume *vol)
102 {
103 	struct g_raid_tr_raid5_object *trs;
104 	u_int qual;
105 
106 	trs = (struct g_raid_tr_raid5_object *)tr;
107 	qual = tr->tro_volume->v_raid_level_qualifier;
108 	if (tr->tro_volume->v_raid_level == G_RAID_VOLUME_RL_RAID4 &&
109 	    (qual == G_RAID_VOLUME_RLQ_R4P0 ||
110 	     qual == G_RAID_VOLUME_RLQ_R4PN)) {
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 == G_RAID_VOLUME_RLQ_R5RA ||
119 	     qual == G_RAID_VOLUME_RLQ_R5RS ||
120 	     qual == G_RAID_VOLUME_RLQ_R5LA ||
121 	     qual == G_RAID_VOLUME_RLQ_R5LS)) {
122 		/* RAID5/5E/5EE/5R/6/MDF */
123 	} else
124 		return (G_RAID_TR_TASTE_FAIL);
125 	trs->trso_starting = 1;
126 	return (G_RAID_TR_TASTE_SUCCEED);
127 }
128 
129 static int
130 g_raid_tr_update_state_raid5(struct g_raid_volume *vol,
131     struct g_raid_subdisk *sd)
132 {
133 	struct g_raid_tr_raid5_object *trs;
134 	struct g_raid_softc *sc;
135 	u_int s;
136 	int na, ns, nu;
137 
138 	sc = vol->v_softc;
139 	trs = (struct g_raid_tr_raid5_object *)vol->v_tr;
140 	if (trs->trso_stopping &&
141 	    (trs->trso_flags & TR_RAID5_F_DOING_SOME) == 0)
142 		s = G_RAID_VOLUME_S_STOPPED;
143 	else if (trs->trso_starting)
144 		s = G_RAID_VOLUME_S_STARTING;
145 	else {
146 		na = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_ACTIVE);
147 		ns = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_STALE) +
148 		     g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_RESYNC);
149 		nu = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_UNINITIALIZED);
150 		if (na == vol->v_disks_count)
151 			s = G_RAID_VOLUME_S_OPTIMAL;
152 		else if (na + ns == vol->v_disks_count ||
153 		    na + ns + nu == vol->v_disks_count /* XXX: Temporary. */)
154 			s = G_RAID_VOLUME_S_SUBOPTIMAL;
155 		else if (na == vol->v_disks_count - 1 ||
156 		    na + ns + nu == vol->v_disks_count)
157 			s = G_RAID_VOLUME_S_DEGRADED;
158 		else
159 			s = G_RAID_VOLUME_S_BROKEN;
160 	}
161 	if (s != vol->v_state) {
162 		g_raid_event_send(vol, G_RAID_VOLUME_S_ALIVE(s) ?
163 		    G_RAID_VOLUME_E_UP : G_RAID_VOLUME_E_DOWN,
164 		    G_RAID_EVENT_VOLUME);
165 		g_raid_change_volume_state(vol, s);
166 		if (!trs->trso_starting && !trs->trso_stopping)
167 			g_raid_write_metadata(sc, vol, NULL, NULL);
168 	}
169 	return (0);
170 }
171 
172 static int
173 g_raid_tr_event_raid5(struct g_raid_tr_object *tr,
174     struct g_raid_subdisk *sd, u_int event)
175 {
176 
177 	g_raid_tr_update_state_raid5(tr->tro_volume, sd);
178 	return (0);
179 }
180 
181 static int
182 g_raid_tr_start_raid5(struct g_raid_tr_object *tr)
183 {
184 	struct g_raid_tr_raid5_object *trs;
185 	struct g_raid_volume *vol;
186 
187 	trs = (struct g_raid_tr_raid5_object *)tr;
188 	trs->trso_starting = 0;
189 	vol = tr->tro_volume;
190 	vol->v_read_only = 1;
191 	g_raid_tr_update_state_raid5(vol, NULL);
192 	return (0);
193 }
194 
195 static int
196 g_raid_tr_stop_raid5(struct g_raid_tr_object *tr)
197 {
198 	struct g_raid_tr_raid5_object *trs;
199 	struct g_raid_volume *vol;
200 
201 	trs = (struct g_raid_tr_raid5_object *)tr;
202 	vol = tr->tro_volume;
203 	trs->trso_starting = 0;
204 	trs->trso_stopping = 1;
205 	g_raid_tr_update_state_raid5(vol, NULL);
206 	return (0);
207 }
208 
209 static void
210 g_raid_tr_iostart_raid5_read(struct g_raid_tr_object *tr, struct bio *bp)
211 {
212 	struct g_raid_volume *vol;
213 	struct g_raid_subdisk *sd;
214 	struct bio_queue_head queue;
215 	struct bio *cbp;
216 	char *addr;
217 	off_t offset, start, length, nstripe, remain;
218 	int no, pno, ddisks, pdisks, protate, pleft;
219 	u_int strip_size, lvl, qual;
220 
221 	vol = tr->tro_volume;
222 	addr = bp->bio_data;
223 	strip_size = vol->v_strip_size;
224 	lvl = tr->tro_volume->v_raid_level;
225 	qual = tr->tro_volume->v_raid_level_qualifier;
226 	protate = tr->tro_volume->v_rotate_parity;
227 
228 	/* Stripe number. */
229 	nstripe = bp->bio_offset / strip_size;
230 	/* Start position in stripe. */
231 	start = bp->bio_offset % strip_size;
232 	/* Number of data and parity disks. */
233 	if (lvl == G_RAID_VOLUME_RL_RAIDMDF)
234 		pdisks = tr->tro_volume->v_mdf_pdisks;
235 	else if (lvl == G_RAID_VOLUME_RL_RAID5EE ||
236 	    lvl == G_RAID_VOLUME_RL_RAID6)
237 		pdisks = 2;
238 	else
239 		pdisks = 1;
240 	ddisks = vol->v_disks_count - pdisks;
241 	/* Parity disk number. */
242 	if (lvl == G_RAID_VOLUME_RL_RAID4) {
243 		if (qual == 0)		/* P0 */
244 			pno = 0;
245 		else			/* PN */
246 			pno = ddisks;
247 		pleft = -1;
248 	} else {
249 		pno = (nstripe / (ddisks * protate)) % vol->v_disks_count;
250 		pleft = protate - (nstripe / ddisks) % protate;
251 		if (qual >= 2) {	/* PN/Left */
252 			pno = ddisks - pno;
253 			if (pno < 0)
254 				pno += vol->v_disks_count;
255 		}
256 	}
257 	/* Data disk number. */
258 	no = nstripe % ddisks;
259 	if (lvl == G_RAID_VOLUME_RL_RAID4) {
260 		if (qual == 0)
261 			no += pdisks;
262 	} else if (qual & 1) {	/* Continuation/Symmetric */
263 		no = (pno + pdisks + no) % vol->v_disks_count;
264 	} else if (no >= pno)	/* Restart/Asymmetric */
265 		no += pdisks;
266 	else
267 		no += imax(0, pno + pdisks - vol->v_disks_count);
268 	/* Stripe start position in disk. */
269 	offset = (nstripe / ddisks) * strip_size;
270 	/* Length of data to operate. */
271 	remain = bp->bio_length;
272 
273 	bioq_init(&queue);
274 	do {
275 		length = MIN(strip_size - start, remain);
276 		cbp = g_clone_bio(bp);
277 		if (cbp == NULL)
278 			goto failure;
279 		cbp->bio_offset = offset + start;
280 		cbp->bio_data = addr;
281 		cbp->bio_length = length;
282 		cbp->bio_caller1 = &vol->v_subdisks[no];
283 		bioq_insert_tail(&queue, cbp);
284 		no++;
285 		if (lvl == G_RAID_VOLUME_RL_RAID4) {
286 			no %= vol->v_disks_count;
287 			if (no == pno)
288 				no = (no + pdisks) % vol->v_disks_count;
289 		} else if (qual & 1) {	/* Continuation/Symmetric */
290 			no %= vol->v_disks_count;
291 			if (no == pno) {
292 				if ((--pleft) <= 0) {
293 					pleft += protate;
294 					if (qual < 2)	/* P0/Right */
295 						pno++;
296 					else		/* PN/Left */
297 						pno += vol->v_disks_count - 1;
298 					pno %= vol->v_disks_count;
299 				}
300 				no = (pno + pdisks) % vol->v_disks_count;
301 				offset += strip_size;
302 			}
303 		} else {		/* Restart/Asymmetric */
304 			if (no == pno)
305 				no += pdisks;
306 			if (no >= vol->v_disks_count) {
307 				no -= vol->v_disks_count;
308 				if ((--pleft) <= 0) {
309 					pleft += protate;
310 					if (qual < 2)	/* P0/Right */
311 						pno++;
312 					else		/* PN/Left */
313 						pno += vol->v_disks_count - 1;
314 					pno %= vol->v_disks_count;
315 				}
316 				if (no == pno)
317 					no += pdisks;
318 				else
319 					no += imax(0, pno + pdisks - vol->v_disks_count);
320 				offset += strip_size;
321 			}
322 		}
323 		remain -= length;
324 		addr += length;
325 		start = 0;
326 	} while (remain > 0);
327 	while ((cbp = bioq_takefirst(&queue)) != NULL) {
328 		sd = cbp->bio_caller1;
329 		cbp->bio_caller1 = NULL;
330 		g_raid_subdisk_iostart(sd, cbp);
331 	}
332 	return;
333 failure:
334 	while ((cbp = bioq_takefirst(&queue)) != NULL)
335 		g_destroy_bio(cbp);
336 	if (bp->bio_error == 0)
337 		bp->bio_error = ENOMEM;
338 	g_raid_iodone(bp, bp->bio_error);
339 }
340 
341 static void
342 g_raid_tr_iostart_raid5(struct g_raid_tr_object *tr, struct bio *bp)
343 {
344 	struct g_raid_volume *vol;
345 	struct g_raid_tr_raid5_object *trs;
346 
347 	vol = tr->tro_volume;
348 	trs = (struct g_raid_tr_raid5_object *)tr;
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 		g_raid_iodone(bp, ENODEV);
361 		break;
362 	default:
363 		KASSERT(1 == 0, ("Invalid command here: %u (volume=%s)",
364 		    bp->bio_cmd, vol->v_name));
365 		break;
366 	}
367 }
368 
369 static void
370 g_raid_tr_iodone_raid5(struct g_raid_tr_object *tr,
371     struct g_raid_subdisk *sd, struct bio *bp)
372 {
373 	struct bio *pbp;
374 	int error;
375 
376 	pbp = bp->bio_parent;
377 	pbp->bio_inbed++;
378 	error = bp->bio_error;
379 	g_destroy_bio(bp);
380 	if (pbp->bio_children == pbp->bio_inbed) {
381 		pbp->bio_completed = pbp->bio_length;
382 		g_raid_iodone(pbp, error);
383 	}
384 }
385 
386 static int
387 g_raid_tr_kerneldump_raid5(struct g_raid_tr_object *tr,
388     void *virtual, vm_offset_t physical, off_t offset, size_t length)
389 {
390 
391 	return (ENODEV);
392 }
393 
394 static int
395 g_raid_tr_locked_raid5(struct g_raid_tr_object *tr, void *argp)
396 {
397 	struct bio *bp;
398 	struct g_raid_subdisk *sd;
399 
400 	bp = (struct bio *)argp;
401 	sd = (struct g_raid_subdisk *)bp->bio_caller1;
402 	g_raid_subdisk_iostart(sd, bp);
403 
404 	return (0);
405 }
406 
407 static int
408 g_raid_tr_free_raid5(struct g_raid_tr_object *tr)
409 {
410 	struct g_raid_tr_raid5_object *trs;
411 
412 	trs = (struct g_raid_tr_raid5_object *)tr;
413 
414 	if (trs->trso_buffer != NULL) {
415 		free(trs->trso_buffer, M_TR_RAID5);
416 		trs->trso_buffer = NULL;
417 	}
418 	return (0);
419 }
420 
421 G_RAID_TR_DECLARE(raid5, "RAID5");
422