xref: /openbsd-src/sys/dev/softraid_raid0.c (revision 6f05df2d9be0954bec42d51d943d77bd250fb664)
1 /* $OpenBSD: softraid_raid0.c,v 1.47 2014/11/18 02:37:30 tedu Exp $ */
2 /*
3  * Copyright (c) 2008 Marco Peereboom <marco@peereboom.us>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include "bio.h"
19 
20 #include <sys/param.h>
21 #include <sys/systm.h>
22 #include <sys/buf.h>
23 #include <sys/device.h>
24 #include <sys/ioctl.h>
25 #include <sys/malloc.h>
26 #include <sys/kernel.h>
27 #include <sys/disk.h>
28 #include <sys/rwlock.h>
29 #include <sys/queue.h>
30 #include <sys/fcntl.h>
31 #include <sys/disklabel.h>
32 #include <sys/mount.h>
33 #include <sys/sensors.h>
34 #include <sys/stat.h>
35 #include <sys/conf.h>
36 #include <sys/uio.h>
37 
38 #include <scsi/scsi_all.h>
39 #include <scsi/scsiconf.h>
40 #include <scsi/scsi_disk.h>
41 
42 #include <dev/softraidvar.h>
43 
44 /* RAID 0 functions. */
45 int	sr_raid0_create(struct sr_discipline *, struct bioc_createraid *,
46 	    int, int64_t);
47 int	sr_raid0_assemble(struct sr_discipline *, struct bioc_createraid *,
48 	    int, void *);
49 int	sr_raid0_init(struct sr_discipline *);
50 int	sr_raid0_rw(struct sr_workunit *);
51 
52 /* Discipline initialisation. */
53 void
54 sr_raid0_discipline_init(struct sr_discipline *sd)
55 {
56 
57 	/* Fill out discipline members. */
58 	sd->sd_type = SR_MD_RAID0;
59 	strlcpy(sd->sd_name, "RAID 0", sizeof(sd->sd_name));
60 	sd->sd_capabilities = SR_CAP_SYSTEM_DISK | SR_CAP_AUTO_ASSEMBLE;
61 	sd->sd_max_wu = SR_RAID0_NOWU;
62 
63 	/* Setup discipline specific function pointers. */
64 	sd->sd_assemble = sr_raid0_assemble;
65 	sd->sd_create = sr_raid0_create;
66 	sd->sd_scsi_rw = sr_raid0_rw;
67 }
68 
69 int
70 sr_raid0_create(struct sr_discipline *sd, struct bioc_createraid *bc,
71     int no_chunk, int64_t coerced_size)
72 {
73 	if (no_chunk < 2) {
74 		sr_error(sd->sd_sc, "%s requires two or more chunks",
75 		    sd->sd_name);
76 		return EINVAL;
77         }
78 
79 	/*
80 	 * XXX add variable strip size later even though MAXPHYS is really
81 	 * the clever value, users like to tinker with that type of stuff.
82 	 */
83 	sd->sd_meta->ssdi.ssd_strip_size = MAXPHYS;
84 	sd->sd_meta->ssdi.ssd_size = (coerced_size &
85 	    ~(((u_int64_t)sd->sd_meta->ssdi.ssd_strip_size >>
86 	    DEV_BSHIFT) - 1)) * no_chunk;
87 
88 	return sr_raid0_init(sd);
89 }
90 
91 int
92 sr_raid0_assemble(struct sr_discipline *sd, struct bioc_createraid *bc,
93     int no_chunks, void *data)
94 {
95 	return sr_raid0_init(sd);
96 }
97 
98 int
99 sr_raid0_init(struct sr_discipline *sd)
100 {
101 	/* Initialise runtime values. */
102 	sd->mds.mdd_raid0.sr0_strip_bits =
103 	    sr_validate_stripsize(sd->sd_meta->ssdi.ssd_strip_size);
104 	if (sd->mds.mdd_raid0.sr0_strip_bits == -1) {
105 		sr_error(sd->sd_sc, "invalid strip size", sd->sd_name);
106 		return EINVAL;
107 	}
108 	sd->sd_max_ccb_per_wu =
109 	    (MAXPHYS / sd->sd_meta->ssdi.ssd_strip_size + 1) *
110 	    SR_RAID0_NOWU * sd->sd_meta->ssdi.ssd_chunk_no;
111 
112 	return 0;
113 }
114 
115 int
116 sr_raid0_rw(struct sr_workunit *wu)
117 {
118 	struct sr_discipline	*sd = wu->swu_dis;
119 	struct scsi_xfer	*xs = wu->swu_xs;
120 	struct sr_ccb		*ccb;
121 	struct sr_chunk		*scp;
122 	daddr_t			blk;
123 	int64_t			chunkoffs, lbaoffs, physoffs, stripoffs;
124 	int64_t			strip_bits, strip_no, strip_size;
125 	int64_t			chunk, no_chunk;
126 	int64_t			length, leftover;
127 	u_int8_t		*data;
128 
129 	/* blk and scsi error will be handled by sr_validate_io */
130 	if (sr_validate_io(wu, &blk, "sr_raid0_rw"))
131 		goto bad;
132 
133 	strip_size = sd->sd_meta->ssdi.ssd_strip_size;
134 	strip_bits = sd->mds.mdd_raid0.sr0_strip_bits;
135 	no_chunk = sd->sd_meta->ssdi.ssd_chunk_no;
136 
137 	DNPRINTF(SR_D_DIS, "%s: %s: front end io: lba %lld size %d\n",
138 	    DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname,
139 	    (long long)blk, xs->datalen);
140 
141 	/* all offs are in bytes */
142 	lbaoffs = blk << DEV_BSHIFT;
143 	strip_no = lbaoffs >> strip_bits;
144 	chunk = strip_no % no_chunk;
145 	stripoffs = lbaoffs & (strip_size - 1);
146 	chunkoffs = (strip_no / no_chunk) << strip_bits;
147 	physoffs = chunkoffs + stripoffs +
148 	    (sd->sd_meta->ssd_data_offset << DEV_BSHIFT);
149 	length = MIN(xs->datalen, strip_size - stripoffs);
150 	leftover = xs->datalen;
151 	data = xs->data;
152 	for (;;) {
153 		/* make sure chunk is online */
154 		scp = sd->sd_vol.sv_chunks[chunk];
155 		if (scp->src_meta.scm_status != BIOC_SDONLINE)
156 			goto bad;
157 
158 		DNPRINTF(SR_D_DIS, "%s: %s %s io lbaoffs %lld "
159 		    "strip_no %lld chunk %lld stripoffs %lld "
160 		    "chunkoffs %lld physoffs %lld length %lld "
161 		    "leftover %lld data %p\n",
162 		    DEVNAME(sd->sd_sc), sd->sd_meta->ssd_devname, sd->sd_name,
163 		    lbaoffs, strip_no, chunk, stripoffs, chunkoffs, physoffs,
164 		    length, leftover, data);
165 
166 		blk = physoffs >> DEV_BSHIFT;
167 		ccb = sr_ccb_rw(sd, chunk, blk, length, data, xs->flags, 0);
168 		if (!ccb) {
169 			/* should never happen but handle more gracefully */
170 			printf("%s: %s: too many ccbs queued\n",
171 			    DEVNAME(sd->sd_sc),
172 			    sd->sd_meta->ssd_devname);
173 			goto bad;
174 		}
175 		sr_wu_enqueue_ccb(wu, ccb);
176 
177 		leftover -= length;
178 		if (leftover == 0)
179 			break;
180 
181 		data += length;
182 		if (++chunk > no_chunk - 1) {
183 			chunk = 0;
184 			physoffs += length;
185 		} else if (wu->swu_io_count == 1)
186 			physoffs -= stripoffs;
187 		length = MIN(leftover,strip_size);
188 	}
189 
190 	sr_schedule_wu(wu);
191 
192 	return (0);
193 
194 bad:
195 	/* wu is unwound by sr_wu_put */
196 	return (1);
197 }
198