1/*-
2 * Copyright (c) 2002 Poul-Henning Kamp
3 * Copyright (c) 2002 Networks Associates Technology, Inc.
4 * All rights reserved.
5 *
6 * This software was developed for the FreeBSD Project by Poul-Henning Kamp
7 * and NAI Labs, the Security Research Division of Network Associates, Inc.
8 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
9 * DARPA CHATS research program.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. The names of the authors may not be used to endorse or promote
20 * products derived from this software without specific prior written
21 * permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
| 1/*-
2 * Copyright (c) 2002 Poul-Henning Kamp
3 * Copyright (c) 2002 Networks Associates Technology, Inc.
4 * All rights reserved.
5 *
6 * This software was developed for the FreeBSD Project by Poul-Henning Kamp
7 * and NAI Labs, the Security Research Division of Network Associates, Inc.
8 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
9 * DARPA CHATS research program.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. The names of the authors may not be used to endorse or promote
20 * products derived from this software without specific prior written
21 * permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
|
35 * $FreeBSD: head/sys/geom/geom_bsd.c 107832 2002-12-13 21:31:13Z phk $
| 35 * $FreeBSD: head/sys/geom/geom_bsd.c 107953 2002-12-16 22:33:27Z phk $
|
36 *
37 * This is the method for dealing with BSD disklabels. It has been
38 * extensively (by my standards at least) commented, in the vain hope that
39 * it will server as the source in future copy&paste operations.
40 */
41
42#include <sys/param.h>
43#ifndef _KERNEL
44#include <stdio.h>
45#include <string.h>
46#include <stdlib.h>
47#include <signal.h>
48#include <err.h>
49#else
50#include <sys/systm.h>
51#include <sys/kernel.h>
52#include <sys/conf.h>
53#include <sys/bio.h>
54#include <sys/malloc.h>
55#include <sys/lock.h>
56#include <sys/mutex.h>
57#endif
58#include <sys/stdint.h>
59#include <sys/errno.h>
60#include <sys/disklabel.h>
61#include <geom/geom.h>
62#include <geom/geom_slice.h>
63
64#define BSD_CLASS_NAME "BSD"
65
66#define ALPHA_LABEL_OFFSET 64
67
68/*
69 * Our private data about one instance. All the rest is handled by the
70 * slice code and stored in its softc, so this is just the stuff
71 * specific to BSD disklabels.
72 */
73struct g_bsd_softc {
74 off_t labeloffset;
75 off_t mbroffset;
76 off_t rawoffset;
77 struct disklabel ondisk;
78 struct disklabel inram;
79};
80
81/*
82 * The next 4 functions isolate us from how the compiler lays out and pads
83 * "struct disklabel". We treat what we read from disk as a bytestream and
84 * explicitly convert it into a struct disklabel. This makes us compiler-
85 * endianness- and wordsize- agnostic.
86 * For now we only have little-endian formats to deal with.
87 */
88
89static void
90g_bsd_ledec_partition(u_char *ptr, struct partition *d)
91{
92 d->p_size = g_dec_le4(ptr + 0);
93 d->p_offset = g_dec_le4(ptr + 4);
94 d->p_fsize = g_dec_le4(ptr + 8);
95 d->p_fstype = ptr[12];
96 d->p_frag = ptr[13];
97 d->p_cpg = g_dec_le2(ptr + 14);
98}
99
100static void
101g_bsd_ledec_disklabel(u_char *ptr, struct disklabel *d)
102{
103 int i;
104
105 d->d_magic = g_dec_le4(ptr + 0);
106 d->d_type = g_dec_le2(ptr + 4);
107 d->d_subtype = g_dec_le2(ptr + 6);
108 bcopy(ptr + 8, d->d_typename, 16);
109 bcopy(ptr + 24, d->d_packname, 16);
110 d->d_secsize = g_dec_le4(ptr + 40);
111 d->d_nsectors = g_dec_le4(ptr + 44);
112 d->d_ntracks = g_dec_le4(ptr + 48);
113 d->d_ncylinders = g_dec_le4(ptr + 52);
114 d->d_secpercyl = g_dec_le4(ptr + 56);
115 d->d_secperunit = g_dec_le4(ptr + 60);
116 d->d_sparespertrack = g_dec_le2(ptr + 64);
117 d->d_sparespercyl = g_dec_le2(ptr + 66);
118 d->d_acylinders = g_dec_le4(ptr + 68);
119 d->d_rpm = g_dec_le2(ptr + 72);
120 d->d_interleave = g_dec_le2(ptr + 74);
121 d->d_trackskew = g_dec_le2(ptr + 76);
122 d->d_cylskew = g_dec_le2(ptr + 78);
123 d->d_headswitch = g_dec_le4(ptr + 80);
124 d->d_trkseek = g_dec_le4(ptr + 84);
125 d->d_flags = g_dec_le4(ptr + 88);
126 d->d_drivedata[0] = g_dec_le4(ptr + 92);
127 d->d_drivedata[1] = g_dec_le4(ptr + 96);
128 d->d_drivedata[2] = g_dec_le4(ptr + 100);
129 d->d_drivedata[3] = g_dec_le4(ptr + 104);
130 d->d_drivedata[4] = g_dec_le4(ptr + 108);
131 d->d_spare[0] = g_dec_le4(ptr + 112);
132 d->d_spare[1] = g_dec_le4(ptr + 116);
133 d->d_spare[2] = g_dec_le4(ptr + 120);
134 d->d_spare[3] = g_dec_le4(ptr + 124);
135 d->d_spare[4] = g_dec_le4(ptr + 128);
136 d->d_magic2 = g_dec_le4(ptr + 132);
137 d->d_checksum = g_dec_le2(ptr + 136);
138 d->d_npartitions = g_dec_le2(ptr + 138);
139 d->d_bbsize = g_dec_le4(ptr + 140);
140 d->d_sbsize = g_dec_le4(ptr + 144);
141 for (i = 0; i < MAXPARTITIONS; i++)
142 g_bsd_ledec_partition(ptr + 148 + 16 * i, &d->d_partitions[i]);
143}
144
145static void
146g_bsd_leenc_partition(u_char *ptr, struct partition *d)
147{
148 g_enc_le4(ptr + 0, d->p_size);
149 g_enc_le4(ptr + 4, d->p_offset);
150 g_enc_le4(ptr + 8, d->p_fsize);
151 ptr[12] = d->p_fstype;
152 ptr[13] = d->p_frag;
153 g_enc_le2(ptr + 14, d->p_cpg);
154}
155
156static void
157g_bsd_leenc_disklabel(u_char *ptr, struct disklabel *d)
158{
159 int i;
160
161 g_enc_le4(ptr + 0, d->d_magic);
162 g_enc_le2(ptr + 4, d->d_type);
163 g_enc_le2(ptr + 6, d->d_subtype);
164 bcopy(d->d_typename, ptr + 8, 16);
165 bcopy(d->d_packname, ptr + 24, 16);
166 g_enc_le4(ptr + 40, d->d_secsize);
167 g_enc_le4(ptr + 44, d->d_nsectors);
168 g_enc_le4(ptr + 48, d->d_ntracks);
169 g_enc_le4(ptr + 52, d->d_ncylinders);
170 g_enc_le4(ptr + 56, d->d_secpercyl);
171 g_enc_le4(ptr + 60, d->d_secperunit);
172 g_enc_le2(ptr + 64, d->d_sparespertrack);
173 g_enc_le2(ptr + 66, d->d_sparespercyl);
174 g_enc_le4(ptr + 68, d->d_acylinders);
175 g_enc_le2(ptr + 72, d->d_rpm);
176 g_enc_le2(ptr + 74, d->d_interleave);
177 g_enc_le2(ptr + 76, d->d_trackskew);
178 g_enc_le2(ptr + 78, d->d_cylskew);
179 g_enc_le4(ptr + 80, d->d_headswitch);
180 g_enc_le4(ptr + 84, d->d_trkseek);
181 g_enc_le4(ptr + 88, d->d_flags);
182 g_enc_le4(ptr + 92, d->d_drivedata[0]);
183 g_enc_le4(ptr + 96, d->d_drivedata[1]);
184 g_enc_le4(ptr + 100, d->d_drivedata[2]);
185 g_enc_le4(ptr + 104, d->d_drivedata[3]);
186 g_enc_le4(ptr + 108, d->d_drivedata[4]);
187 g_enc_le4(ptr + 112, d->d_spare[0]);
188 g_enc_le4(ptr + 116, d->d_spare[1]);
189 g_enc_le4(ptr + 120, d->d_spare[2]);
190 g_enc_le4(ptr + 124, d->d_spare[3]);
191 g_enc_le4(ptr + 128, d->d_spare[4]);
192 g_enc_le4(ptr + 132, d->d_magic2);
193 g_enc_le2(ptr + 136, d->d_checksum);
194 g_enc_le2(ptr + 138, d->d_npartitions);
195 g_enc_le4(ptr + 140, d->d_bbsize);
196 g_enc_le4(ptr + 144, d->d_sbsize);
197 for (i = 0; i < MAXPARTITIONS; i++)
198 g_bsd_leenc_partition(ptr + 148 + 16 * i, &d->d_partitions[i]);
199}
200
201static int
202g_bsd_ondisk_size(void)
203{
204 return (148 + 16 * MAXPARTITIONS);
205}
206
207/*
208 * For reasons which were valid and just in their days, FreeBSD/i386 uses
209 * absolute disk-addresses in disklabels. The way it works is that the
210 * p_offset field of all partitions have the first sector number of the
211 * disk slice added to them. This was hidden kernel-magic, userland did
212 * not see these offsets. These two functions subtract and add them
213 * while converting from the "ondisk" to the "inram" labels and vice
214 * versa.
215 */
216static void
217ondisk2inram(struct g_bsd_softc *sc)
218{
219 struct partition *ppp;
220 struct disklabel *dl;
221 int i;
222
223 sc->inram = sc->ondisk;
224 dl = &sc->inram;
225
226 /* Basic sanity-check needed to avoid mistakes. */
227 if (dl->d_magic != DISKMAGIC || dl->d_magic2 != DISKMAGIC)
228 return;
229 if (dl->d_npartitions > MAXPARTITIONS)
230 return;
231
232 sc->rawoffset = dl->d_partitions[RAW_PART].p_offset;
233 for (i = 0; i < dl->d_npartitions; i++) {
234 ppp = &dl->d_partitions[i];
235 if (ppp->p_size != 0 && ppp->p_offset < sc->rawoffset)
236 sc->rawoffset = 0;
237 }
238 if (sc->rawoffset > 0) {
239 for (i = 0; i < dl->d_npartitions; i++) {
240 ppp = &dl->d_partitions[i];
241 if (ppp->p_offset != 0)
242 ppp->p_offset -= sc->rawoffset;
243 }
244 }
245 dl->d_checksum = 0;
246 dl->d_checksum = dkcksum(&sc->inram);
247}
248
249static void
250inram2ondisk(struct g_bsd_softc *sc)
251{
252 struct partition *ppp;
253 int i;
254
255 sc->ondisk = sc->inram;
256 if (sc->mbroffset != 0)
257 sc->rawoffset = sc->mbroffset / sc->inram.d_secsize;
258 if (sc->rawoffset != 0) {
259 for (i = 0; i < sc->inram.d_npartitions; i++) {
260 ppp = &sc->ondisk.d_partitions[i];
261 if (ppp->p_size > 0)
262 ppp->p_offset += sc->rawoffset;
263 else
264 ppp->p_offset = 0;
265 }
266 }
267 sc->ondisk.d_checksum = 0;
268 sc->ondisk.d_checksum = dkcksum(&sc->ondisk);
269}
270
271/*
272 * Check that this looks like a valid disklabel, but be prepared
273 * to get any kind of junk. The checksum must be checked only
274 * after this function returns success to prevent a bogus d_npartitions
275 * value from tripping us up.
276 */
277static int
278g_bsd_checklabel(struct disklabel *dl)
279{
280 struct partition *ppp;
281 int i;
282
283 if (dl->d_magic != DISKMAGIC || dl->d_magic2 != DISKMAGIC)
284 return (EINVAL);
285 /*
286 * If the label specifies more partitions than we can handle
287 * we have to reject it: If people updated the label they would
288 * trash it, and that would break the checksum.
289 */
290 if (dl->d_npartitions > MAXPARTITIONS)
291 return (EINVAL);
292
293 for (i = 0; i < dl->d_npartitions; i++) {
294 ppp = &dl->d_partitions[i];
295 /* Cannot extend past unit. */
296 if (ppp->p_size != 0 &&
297 ppp->p_offset + ppp->p_size > dl->d_secperunit) {
298 return (EINVAL);
299 }
300 }
301 return (0);
302}
303
304/*
305 * Modify our slicer to match proposed disklabel, if possible.
306 * First carry out all the simple checks, then lock topology
307 * and check that no open providers are affected negatively
308 * then carry out all the changes.
309 *
310 * NB: Returns with topology held only if successful return.
311 */
312static int
313g_bsd_modify(struct g_geom *gp, struct disklabel *dl)
314{
315 int i, error;
316 struct partition *ppp;
317 struct g_slicer *gsp;
318 struct g_consumer *cp;
| 36 *
37 * This is the method for dealing with BSD disklabels. It has been
38 * extensively (by my standards at least) commented, in the vain hope that
39 * it will server as the source in future copy&paste operations.
40 */
41
42#include <sys/param.h>
43#ifndef _KERNEL
44#include <stdio.h>
45#include <string.h>
46#include <stdlib.h>
47#include <signal.h>
48#include <err.h>
49#else
50#include <sys/systm.h>
51#include <sys/kernel.h>
52#include <sys/conf.h>
53#include <sys/bio.h>
54#include <sys/malloc.h>
55#include <sys/lock.h>
56#include <sys/mutex.h>
57#endif
58#include <sys/stdint.h>
59#include <sys/errno.h>
60#include <sys/disklabel.h>
61#include <geom/geom.h>
62#include <geom/geom_slice.h>
63
64#define BSD_CLASS_NAME "BSD"
65
66#define ALPHA_LABEL_OFFSET 64
67
68/*
69 * Our private data about one instance. All the rest is handled by the
70 * slice code and stored in its softc, so this is just the stuff
71 * specific to BSD disklabels.
72 */
73struct g_bsd_softc {
74 off_t labeloffset;
75 off_t mbroffset;
76 off_t rawoffset;
77 struct disklabel ondisk;
78 struct disklabel inram;
79};
80
81/*
82 * The next 4 functions isolate us from how the compiler lays out and pads
83 * "struct disklabel". We treat what we read from disk as a bytestream and
84 * explicitly convert it into a struct disklabel. This makes us compiler-
85 * endianness- and wordsize- agnostic.
86 * For now we only have little-endian formats to deal with.
87 */
88
89static void
90g_bsd_ledec_partition(u_char *ptr, struct partition *d)
91{
92 d->p_size = g_dec_le4(ptr + 0);
93 d->p_offset = g_dec_le4(ptr + 4);
94 d->p_fsize = g_dec_le4(ptr + 8);
95 d->p_fstype = ptr[12];
96 d->p_frag = ptr[13];
97 d->p_cpg = g_dec_le2(ptr + 14);
98}
99
100static void
101g_bsd_ledec_disklabel(u_char *ptr, struct disklabel *d)
102{
103 int i;
104
105 d->d_magic = g_dec_le4(ptr + 0);
106 d->d_type = g_dec_le2(ptr + 4);
107 d->d_subtype = g_dec_le2(ptr + 6);
108 bcopy(ptr + 8, d->d_typename, 16);
109 bcopy(ptr + 24, d->d_packname, 16);
110 d->d_secsize = g_dec_le4(ptr + 40);
111 d->d_nsectors = g_dec_le4(ptr + 44);
112 d->d_ntracks = g_dec_le4(ptr + 48);
113 d->d_ncylinders = g_dec_le4(ptr + 52);
114 d->d_secpercyl = g_dec_le4(ptr + 56);
115 d->d_secperunit = g_dec_le4(ptr + 60);
116 d->d_sparespertrack = g_dec_le2(ptr + 64);
117 d->d_sparespercyl = g_dec_le2(ptr + 66);
118 d->d_acylinders = g_dec_le4(ptr + 68);
119 d->d_rpm = g_dec_le2(ptr + 72);
120 d->d_interleave = g_dec_le2(ptr + 74);
121 d->d_trackskew = g_dec_le2(ptr + 76);
122 d->d_cylskew = g_dec_le2(ptr + 78);
123 d->d_headswitch = g_dec_le4(ptr + 80);
124 d->d_trkseek = g_dec_le4(ptr + 84);
125 d->d_flags = g_dec_le4(ptr + 88);
126 d->d_drivedata[0] = g_dec_le4(ptr + 92);
127 d->d_drivedata[1] = g_dec_le4(ptr + 96);
128 d->d_drivedata[2] = g_dec_le4(ptr + 100);
129 d->d_drivedata[3] = g_dec_le4(ptr + 104);
130 d->d_drivedata[4] = g_dec_le4(ptr + 108);
131 d->d_spare[0] = g_dec_le4(ptr + 112);
132 d->d_spare[1] = g_dec_le4(ptr + 116);
133 d->d_spare[2] = g_dec_le4(ptr + 120);
134 d->d_spare[3] = g_dec_le4(ptr + 124);
135 d->d_spare[4] = g_dec_le4(ptr + 128);
136 d->d_magic2 = g_dec_le4(ptr + 132);
137 d->d_checksum = g_dec_le2(ptr + 136);
138 d->d_npartitions = g_dec_le2(ptr + 138);
139 d->d_bbsize = g_dec_le4(ptr + 140);
140 d->d_sbsize = g_dec_le4(ptr + 144);
141 for (i = 0; i < MAXPARTITIONS; i++)
142 g_bsd_ledec_partition(ptr + 148 + 16 * i, &d->d_partitions[i]);
143}
144
145static void
146g_bsd_leenc_partition(u_char *ptr, struct partition *d)
147{
148 g_enc_le4(ptr + 0, d->p_size);
149 g_enc_le4(ptr + 4, d->p_offset);
150 g_enc_le4(ptr + 8, d->p_fsize);
151 ptr[12] = d->p_fstype;
152 ptr[13] = d->p_frag;
153 g_enc_le2(ptr + 14, d->p_cpg);
154}
155
156static void
157g_bsd_leenc_disklabel(u_char *ptr, struct disklabel *d)
158{
159 int i;
160
161 g_enc_le4(ptr + 0, d->d_magic);
162 g_enc_le2(ptr + 4, d->d_type);
163 g_enc_le2(ptr + 6, d->d_subtype);
164 bcopy(d->d_typename, ptr + 8, 16);
165 bcopy(d->d_packname, ptr + 24, 16);
166 g_enc_le4(ptr + 40, d->d_secsize);
167 g_enc_le4(ptr + 44, d->d_nsectors);
168 g_enc_le4(ptr + 48, d->d_ntracks);
169 g_enc_le4(ptr + 52, d->d_ncylinders);
170 g_enc_le4(ptr + 56, d->d_secpercyl);
171 g_enc_le4(ptr + 60, d->d_secperunit);
172 g_enc_le2(ptr + 64, d->d_sparespertrack);
173 g_enc_le2(ptr + 66, d->d_sparespercyl);
174 g_enc_le4(ptr + 68, d->d_acylinders);
175 g_enc_le2(ptr + 72, d->d_rpm);
176 g_enc_le2(ptr + 74, d->d_interleave);
177 g_enc_le2(ptr + 76, d->d_trackskew);
178 g_enc_le2(ptr + 78, d->d_cylskew);
179 g_enc_le4(ptr + 80, d->d_headswitch);
180 g_enc_le4(ptr + 84, d->d_trkseek);
181 g_enc_le4(ptr + 88, d->d_flags);
182 g_enc_le4(ptr + 92, d->d_drivedata[0]);
183 g_enc_le4(ptr + 96, d->d_drivedata[1]);
184 g_enc_le4(ptr + 100, d->d_drivedata[2]);
185 g_enc_le4(ptr + 104, d->d_drivedata[3]);
186 g_enc_le4(ptr + 108, d->d_drivedata[4]);
187 g_enc_le4(ptr + 112, d->d_spare[0]);
188 g_enc_le4(ptr + 116, d->d_spare[1]);
189 g_enc_le4(ptr + 120, d->d_spare[2]);
190 g_enc_le4(ptr + 124, d->d_spare[3]);
191 g_enc_le4(ptr + 128, d->d_spare[4]);
192 g_enc_le4(ptr + 132, d->d_magic2);
193 g_enc_le2(ptr + 136, d->d_checksum);
194 g_enc_le2(ptr + 138, d->d_npartitions);
195 g_enc_le4(ptr + 140, d->d_bbsize);
196 g_enc_le4(ptr + 144, d->d_sbsize);
197 for (i = 0; i < MAXPARTITIONS; i++)
198 g_bsd_leenc_partition(ptr + 148 + 16 * i, &d->d_partitions[i]);
199}
200
201static int
202g_bsd_ondisk_size(void)
203{
204 return (148 + 16 * MAXPARTITIONS);
205}
206
207/*
208 * For reasons which were valid and just in their days, FreeBSD/i386 uses
209 * absolute disk-addresses in disklabels. The way it works is that the
210 * p_offset field of all partitions have the first sector number of the
211 * disk slice added to them. This was hidden kernel-magic, userland did
212 * not see these offsets. These two functions subtract and add them
213 * while converting from the "ondisk" to the "inram" labels and vice
214 * versa.
215 */
216static void
217ondisk2inram(struct g_bsd_softc *sc)
218{
219 struct partition *ppp;
220 struct disklabel *dl;
221 int i;
222
223 sc->inram = sc->ondisk;
224 dl = &sc->inram;
225
226 /* Basic sanity-check needed to avoid mistakes. */
227 if (dl->d_magic != DISKMAGIC || dl->d_magic2 != DISKMAGIC)
228 return;
229 if (dl->d_npartitions > MAXPARTITIONS)
230 return;
231
232 sc->rawoffset = dl->d_partitions[RAW_PART].p_offset;
233 for (i = 0; i < dl->d_npartitions; i++) {
234 ppp = &dl->d_partitions[i];
235 if (ppp->p_size != 0 && ppp->p_offset < sc->rawoffset)
236 sc->rawoffset = 0;
237 }
238 if (sc->rawoffset > 0) {
239 for (i = 0; i < dl->d_npartitions; i++) {
240 ppp = &dl->d_partitions[i];
241 if (ppp->p_offset != 0)
242 ppp->p_offset -= sc->rawoffset;
243 }
244 }
245 dl->d_checksum = 0;
246 dl->d_checksum = dkcksum(&sc->inram);
247}
248
249static void
250inram2ondisk(struct g_bsd_softc *sc)
251{
252 struct partition *ppp;
253 int i;
254
255 sc->ondisk = sc->inram;
256 if (sc->mbroffset != 0)
257 sc->rawoffset = sc->mbroffset / sc->inram.d_secsize;
258 if (sc->rawoffset != 0) {
259 for (i = 0; i < sc->inram.d_npartitions; i++) {
260 ppp = &sc->ondisk.d_partitions[i];
261 if (ppp->p_size > 0)
262 ppp->p_offset += sc->rawoffset;
263 else
264 ppp->p_offset = 0;
265 }
266 }
267 sc->ondisk.d_checksum = 0;
268 sc->ondisk.d_checksum = dkcksum(&sc->ondisk);
269}
270
271/*
272 * Check that this looks like a valid disklabel, but be prepared
273 * to get any kind of junk. The checksum must be checked only
274 * after this function returns success to prevent a bogus d_npartitions
275 * value from tripping us up.
276 */
277static int
278g_bsd_checklabel(struct disklabel *dl)
279{
280 struct partition *ppp;
281 int i;
282
283 if (dl->d_magic != DISKMAGIC || dl->d_magic2 != DISKMAGIC)
284 return (EINVAL);
285 /*
286 * If the label specifies more partitions than we can handle
287 * we have to reject it: If people updated the label they would
288 * trash it, and that would break the checksum.
289 */
290 if (dl->d_npartitions > MAXPARTITIONS)
291 return (EINVAL);
292
293 for (i = 0; i < dl->d_npartitions; i++) {
294 ppp = &dl->d_partitions[i];
295 /* Cannot extend past unit. */
296 if (ppp->p_size != 0 &&
297 ppp->p_offset + ppp->p_size > dl->d_secperunit) {
298 return (EINVAL);
299 }
300 }
301 return (0);
302}
303
304/*
305 * Modify our slicer to match proposed disklabel, if possible.
306 * First carry out all the simple checks, then lock topology
307 * and check that no open providers are affected negatively
308 * then carry out all the changes.
309 *
310 * NB: Returns with topology held only if successful return.
311 */
312static int
313g_bsd_modify(struct g_geom *gp, struct disklabel *dl)
314{
315 int i, error;
316 struct partition *ppp;
317 struct g_slicer *gsp;
318 struct g_consumer *cp;
|
319 u_int secsize;
| 319 u_int secsize, u;
|
320 off_t mediasize;
321
322 /* Basic check that this is indeed a disklabel. */
323 error = g_bsd_checklabel(dl);
324 if (error)
325 return (error);
326
327 /* Make sure the checksum is OK. */
328 if (dkcksum(dl) != 0)
329 return (EINVAL);
330
331 /* Get dimensions of our device. */
332 cp = LIST_FIRST(&gp->consumer);
333 secsize = cp->provider->sectorsize;
334 mediasize = cp->provider->mediasize;
335
336#ifdef nolonger
337 /*
338 * The raw-partition must start at zero. We do not check that the
339 * size == mediasize because this is overly restrictive. We have
340 * already tested in g_bsd_checklabel() that it is not longer.
341 * XXX: RAW_PART is archaic anyway, and we should drop it.
342 */
343 if (dl->d_partitions[RAW_PART].p_offset != 0)
344 return (EINVAL);
345#endif
346
347#ifdef notyet
348 /*
349 * Indications are that the d_secperunit is not correctly
350 * initialized in many cases, and since we don't need it
351 * for anything, we dont strictly need this test.
352 * Preemptive action to avoid confusing people in disklabel(8)
353 * may be in order.
354 */
355 /* The label cannot claim a larger size than the media. */
356 if ((off_t)dl->d_secperunit * dl->d_secsize > mediasize)
357 return (EINVAL);
358#endif
359
360
361 /* ... or a smaller sector size. */
362 if (dl->d_secsize < secsize)
363 return (EINVAL);
364
365 /* ... or a non-multiple sector size. */
366 if (dl->d_secsize % secsize != 0)
367 return (EINVAL);
368
369 g_topology_lock();
370
371 /* Don't munge open partitions. */
372 gsp = gp->softc;
373 for (i = 0; i < dl->d_npartitions; i++) {
374 ppp = &dl->d_partitions[i];
375
376 error = g_slice_config(gp, i, G_SLICE_CONFIG_CHECK,
377 (off_t)ppp->p_offset * dl->d_secsize,
378 (off_t)ppp->p_size * dl->d_secsize,
379 dl->d_secsize,
380 "%s%c", gp->name, 'a' + i);
381 if (error) {
382 g_topology_unlock();
383 return (error);
384 }
385 }
386
387 /* Look good, go for it... */
| 320 off_t mediasize;
321
322 /* Basic check that this is indeed a disklabel. */
323 error = g_bsd_checklabel(dl);
324 if (error)
325 return (error);
326
327 /* Make sure the checksum is OK. */
328 if (dkcksum(dl) != 0)
329 return (EINVAL);
330
331 /* Get dimensions of our device. */
332 cp = LIST_FIRST(&gp->consumer);
333 secsize = cp->provider->sectorsize;
334 mediasize = cp->provider->mediasize;
335
336#ifdef nolonger
337 /*
338 * The raw-partition must start at zero. We do not check that the
339 * size == mediasize because this is overly restrictive. We have
340 * already tested in g_bsd_checklabel() that it is not longer.
341 * XXX: RAW_PART is archaic anyway, and we should drop it.
342 */
343 if (dl->d_partitions[RAW_PART].p_offset != 0)
344 return (EINVAL);
345#endif
346
347#ifdef notyet
348 /*
349 * Indications are that the d_secperunit is not correctly
350 * initialized in many cases, and since we don't need it
351 * for anything, we dont strictly need this test.
352 * Preemptive action to avoid confusing people in disklabel(8)
353 * may be in order.
354 */
355 /* The label cannot claim a larger size than the media. */
356 if ((off_t)dl->d_secperunit * dl->d_secsize > mediasize)
357 return (EINVAL);
358#endif
359
360
361 /* ... or a smaller sector size. */
362 if (dl->d_secsize < secsize)
363 return (EINVAL);
364
365 /* ... or a non-multiple sector size. */
366 if (dl->d_secsize % secsize != 0)
367 return (EINVAL);
368
369 g_topology_lock();
370
371 /* Don't munge open partitions. */
372 gsp = gp->softc;
373 for (i = 0; i < dl->d_npartitions; i++) {
374 ppp = &dl->d_partitions[i];
375
376 error = g_slice_config(gp, i, G_SLICE_CONFIG_CHECK,
377 (off_t)ppp->p_offset * dl->d_secsize,
378 (off_t)ppp->p_size * dl->d_secsize,
379 dl->d_secsize,
380 "%s%c", gp->name, 'a' + i);
381 if (error) {
382 g_topology_unlock();
383 return (error);
384 }
385 }
386
387 /* Look good, go for it... */
|
388 for (i = 0; i < gsp->nslice; i++) {
389 ppp = &dl->d_partitions[i];
390 g_slice_config(gp, i, G_SLICE_CONFIG_SET,
| 388 for (u = 0; u < gsp->nslice; u++) {
389 ppp = &dl->d_partitions[u];
390 g_slice_config(gp, u, G_SLICE_CONFIG_SET,
|
391 (off_t)ppp->p_offset * dl->d_secsize,
392 (off_t)ppp->p_size * dl->d_secsize,
393 dl->d_secsize,
| 391 (off_t)ppp->p_offset * dl->d_secsize,
392 (off_t)ppp->p_size * dl->d_secsize,
393 dl->d_secsize,
|
394 "%s%c", gp->name, 'a' + i);
| 394 "%s%c", gp->name, 'a' + u);
|
395 }
396 return (0);
397}
398
399/*
400 * Calculate a disklabel checksum for a little-endian byte-stream.
401 * We need access to the decoded disklabel because the checksum only
402 * covers the partition data for the first d_npartitions.
403 */
404static int
405g_bsd_lesum(struct disklabel *dl, u_char *p)
406{
407 u_char *pe;
408 uint16_t sum;
409
410 pe = p + 148 + 16 * dl->d_npartitions;
411 sum = 0;
412 while (p < pe) {
413 sum ^= g_dec_le2(p);
414 p += 2;
415 }
416 return (sum);
417}
418
419/*
420 * This is an internal helper function, called multiple times from the taste
421 * function to try to locate a disklabel on the disk. More civilized formats
422 * will not need this, as there is only one possible place on disk to look
423 * for the magic spot.
424 */
425
426static int
427g_bsd_try(struct g_geom *gp, struct g_slicer *gsp, struct g_consumer *cp, int secsize, struct g_bsd_softc *ms, off_t offset)
428{
429 int error;
430 u_char *buf;
431 struct disklabel *dl;
432 off_t secoff;
433
434 /*
435 * We need to read entire aligned sectors, and we assume that the
436 * disklabel does not span sectors, so one sector is enough.
437 */
438 error = 0;
439 secoff = offset % secsize;
440 buf = g_read_data(cp, offset - secoff, secsize, &error);
441 if (buf == NULL || error != 0)
442 return (ENOENT);
443
444 /* Decode into our native format. */
445 dl = &ms->ondisk;
446 g_bsd_ledec_disklabel(buf + secoff, dl);
447
448 ondisk2inram(ms);
449
450 dl = &ms->inram;
451 /* Does it look like a label at all? */
452 if (g_bsd_checklabel(dl))
453 error = ENOENT;
454 /* ... and does the raw data have a good checksum? */
455 if (error == 0 && g_bsd_lesum(dl, buf + secoff) != 0)
456 error = ENOENT;
457
458 /* Remember to free the buffer g_read_data() gave us. */
459 g_free(buf);
460
461 /* If we had a label, record it properly. */
462 if (error == 0) {
463 gsp->frontstuff = 16 * secsize; /* XXX */
464 ms->labeloffset = offset;
465 g_topology_lock();
466 g_slice_conf_hot(gp, 0, offset, g_bsd_ondisk_size());
467 g_topology_unlock();
468 }
469 return (error);
470}
471
472/*
473 * Implement certain ioctls to modify disklabels with. This function
474 * is called by the event handler thread with topology locked as result
475 * of the g_call_me() in g_bsd_start(). It is not necessary to keep
476 * topology locked all the time but make sure to return with topology
477 * locked as well.
478 */
479
480static void
481g_bsd_ioctl(void *arg)
482{
483 struct bio *bp;
484 struct g_geom *gp;
485 struct g_slicer *gsp;
486 struct g_bsd_softc *ms;
487 struct disklabel *dl;
488 struct g_ioctl *gio;
489 struct g_consumer *cp;
490 u_char *buf;
491 off_t secoff;
492 u_int secsize;
493 int error, i;
494 uint64_t sum;
495
496 /* We don't need topology for now. */
497 g_topology_unlock();
498
499 /* Get hold of the interesting bits from the bio. */
500 bp = arg;
501 gp = bp->bio_to->geom;
502 gsp = gp->softc;
503 ms = gsp->softc;
504 gio = (struct g_ioctl *)bp->bio_data;
505
506 /* The disklabel to set is the ioctl argument. */
507 dl = gio->data;
508
509 /* Validate and modify our slice instance to match. */
510 error = g_bsd_modify(gp, dl); /* Picks up topology lock on success. */
511 if (error) {
512 g_topology_lock();
513 g_io_deliver(bp, error);
514 return;
515 }
516 /* Update our copy of the disklabel. */
517 ms->inram = *dl;
518 inram2ondisk(ms);
519
520 if (gio->cmd == DIOCSDINFO) {
521 g_io_deliver(bp, 0);
522 return;
523 }
524 KASSERT(gio->cmd == DIOCWDINFO, ("Unknown ioctl in g_bsd_ioctl"));
525 cp = LIST_FIRST(&gp->consumer);
526 /* Get sector size, we need it to read data. */
527 secsize = cp->provider->sectorsize;
528 secoff = ms->labeloffset % secsize;
529 buf = g_read_data(cp, ms->labeloffset - secoff, secsize, &error);
530 if (buf == NULL || error != 0) {
531 g_io_deliver(bp, error);
532 return;
533 }
534 dl = &ms->ondisk;
535 g_bsd_leenc_disklabel(buf + secoff, dl);
536 if (ms->labeloffset == ALPHA_LABEL_OFFSET) {
537 sum = 0;
538 for (i = 0; i < 63; i++)
539 sum += g_dec_le8(buf + i * 8);
540 g_enc_le8(buf + 504, sum);
541 }
542 error = g_write_data(cp, ms->labeloffset - secoff, buf, secsize);
543 g_free(buf);
544 g_io_deliver(bp, error);
545}
546
547/*
548 * If the user tries to overwrite our disklabel through an open partition
549 * or via a magicwrite config call, we end up here and try to prevent
550 * footshooting as best we can.
551 */
552static void
553g_bsd_hotwrite(void *arg)
554{
555 struct bio *bp;
556 struct g_geom *gp;
557 struct g_slicer *gsp;
558 struct g_slice *gsl;
559 struct g_bsd_softc *ms;
560 struct g_bsd_softc fake;
561 u_char *p;
562 int error;
563
564 bp = arg;
565 gp = bp->bio_to->geom;
566 gsp = gp->softc;
567 ms = gsp->softc;
568 gsl = &gsp->slices[bp->bio_to->index];
| 395 }
396 return (0);
397}
398
399/*
400 * Calculate a disklabel checksum for a little-endian byte-stream.
401 * We need access to the decoded disklabel because the checksum only
402 * covers the partition data for the first d_npartitions.
403 */
404static int
405g_bsd_lesum(struct disklabel *dl, u_char *p)
406{
407 u_char *pe;
408 uint16_t sum;
409
410 pe = p + 148 + 16 * dl->d_npartitions;
411 sum = 0;
412 while (p < pe) {
413 sum ^= g_dec_le2(p);
414 p += 2;
415 }
416 return (sum);
417}
418
419/*
420 * This is an internal helper function, called multiple times from the taste
421 * function to try to locate a disklabel on the disk. More civilized formats
422 * will not need this, as there is only one possible place on disk to look
423 * for the magic spot.
424 */
425
426static int
427g_bsd_try(struct g_geom *gp, struct g_slicer *gsp, struct g_consumer *cp, int secsize, struct g_bsd_softc *ms, off_t offset)
428{
429 int error;
430 u_char *buf;
431 struct disklabel *dl;
432 off_t secoff;
433
434 /*
435 * We need to read entire aligned sectors, and we assume that the
436 * disklabel does not span sectors, so one sector is enough.
437 */
438 error = 0;
439 secoff = offset % secsize;
440 buf = g_read_data(cp, offset - secoff, secsize, &error);
441 if (buf == NULL || error != 0)
442 return (ENOENT);
443
444 /* Decode into our native format. */
445 dl = &ms->ondisk;
446 g_bsd_ledec_disklabel(buf + secoff, dl);
447
448 ondisk2inram(ms);
449
450 dl = &ms->inram;
451 /* Does it look like a label at all? */
452 if (g_bsd_checklabel(dl))
453 error = ENOENT;
454 /* ... and does the raw data have a good checksum? */
455 if (error == 0 && g_bsd_lesum(dl, buf + secoff) != 0)
456 error = ENOENT;
457
458 /* Remember to free the buffer g_read_data() gave us. */
459 g_free(buf);
460
461 /* If we had a label, record it properly. */
462 if (error == 0) {
463 gsp->frontstuff = 16 * secsize; /* XXX */
464 ms->labeloffset = offset;
465 g_topology_lock();
466 g_slice_conf_hot(gp, 0, offset, g_bsd_ondisk_size());
467 g_topology_unlock();
468 }
469 return (error);
470}
471
472/*
473 * Implement certain ioctls to modify disklabels with. This function
474 * is called by the event handler thread with topology locked as result
475 * of the g_call_me() in g_bsd_start(). It is not necessary to keep
476 * topology locked all the time but make sure to return with topology
477 * locked as well.
478 */
479
480static void
481g_bsd_ioctl(void *arg)
482{
483 struct bio *bp;
484 struct g_geom *gp;
485 struct g_slicer *gsp;
486 struct g_bsd_softc *ms;
487 struct disklabel *dl;
488 struct g_ioctl *gio;
489 struct g_consumer *cp;
490 u_char *buf;
491 off_t secoff;
492 u_int secsize;
493 int error, i;
494 uint64_t sum;
495
496 /* We don't need topology for now. */
497 g_topology_unlock();
498
499 /* Get hold of the interesting bits from the bio. */
500 bp = arg;
501 gp = bp->bio_to->geom;
502 gsp = gp->softc;
503 ms = gsp->softc;
504 gio = (struct g_ioctl *)bp->bio_data;
505
506 /* The disklabel to set is the ioctl argument. */
507 dl = gio->data;
508
509 /* Validate and modify our slice instance to match. */
510 error = g_bsd_modify(gp, dl); /* Picks up topology lock on success. */
511 if (error) {
512 g_topology_lock();
513 g_io_deliver(bp, error);
514 return;
515 }
516 /* Update our copy of the disklabel. */
517 ms->inram = *dl;
518 inram2ondisk(ms);
519
520 if (gio->cmd == DIOCSDINFO) {
521 g_io_deliver(bp, 0);
522 return;
523 }
524 KASSERT(gio->cmd == DIOCWDINFO, ("Unknown ioctl in g_bsd_ioctl"));
525 cp = LIST_FIRST(&gp->consumer);
526 /* Get sector size, we need it to read data. */
527 secsize = cp->provider->sectorsize;
528 secoff = ms->labeloffset % secsize;
529 buf = g_read_data(cp, ms->labeloffset - secoff, secsize, &error);
530 if (buf == NULL || error != 0) {
531 g_io_deliver(bp, error);
532 return;
533 }
534 dl = &ms->ondisk;
535 g_bsd_leenc_disklabel(buf + secoff, dl);
536 if (ms->labeloffset == ALPHA_LABEL_OFFSET) {
537 sum = 0;
538 for (i = 0; i < 63; i++)
539 sum += g_dec_le8(buf + i * 8);
540 g_enc_le8(buf + 504, sum);
541 }
542 error = g_write_data(cp, ms->labeloffset - secoff, buf, secsize);
543 g_free(buf);
544 g_io_deliver(bp, error);
545}
546
547/*
548 * If the user tries to overwrite our disklabel through an open partition
549 * or via a magicwrite config call, we end up here and try to prevent
550 * footshooting as best we can.
551 */
552static void
553g_bsd_hotwrite(void *arg)
554{
555 struct bio *bp;
556 struct g_geom *gp;
557 struct g_slicer *gsp;
558 struct g_slice *gsl;
559 struct g_bsd_softc *ms;
560 struct g_bsd_softc fake;
561 u_char *p;
562 int error;
563
564 bp = arg;
565 gp = bp->bio_to->geom;
566 gsp = gp->softc;
567 ms = gsp->softc;
568 gsl = &gsp->slices[bp->bio_to->index];
|
569 p = bp->bio_data + ms->labeloffset
| 569 p = (u_char*)bp->bio_data + ms->labeloffset
|
570 - (bp->bio_offset + gsl->offset);
571 g_bsd_ledec_disklabel(p, &fake.ondisk);
572
573 ondisk2inram(&fake);
574 if (g_bsd_checklabel(&fake.inram)) {
575 g_io_deliver(bp, EPERM);
576 return;
577 }
578 if (g_bsd_lesum(&fake.ondisk, p) != 0) {
579 g_io_deliver(bp, EPERM);
580 return;
581 }
582 g_topology_unlock();
583 error = g_bsd_modify(gp, &fake.inram); /* May pick up topology. */
584 if (error) {
585 g_io_deliver(bp, EPERM);
586 g_topology_lock();
587 return;
588 }
589 /* Update our copy of the disklabel. */
590 ms->inram = fake.inram;
591 inram2ondisk(ms);
592 g_bsd_leenc_disklabel(p, &ms->ondisk);
593 g_slice_finish_hot(bp);
594}
595
596/*-
597 * This start routine is only called for non-trivial requests, all the
598 * trivial ones are handled autonomously by the slice code.
599 * For requests we handle here, we must call the g_io_deliver() on the
600 * bio, and return non-zero to indicate to the slice code that we did so.
601 * This code executes in the "DOWN" I/O path, this means:
602 * * No sleeping.
603 * * Don't grab the topology lock.
604 * * Don't call biowait, g_getattr(), g_setattr() or g_read_data()
605 */
606
607static int
608g_bsd_start(struct bio *bp)
609{
610 struct g_geom *gp;
611 struct g_bsd_softc *ms;
612 struct g_slicer *gsp;
613 struct g_ioctl *gio;
614 int error;
615
616 gp = bp->bio_to->geom;
617 gsp = gp->softc;
618 ms = gsp->softc;
619 switch(bp->bio_cmd) {
620 case BIO_READ:
621 /* We allow reading of our hot spots */
622 return (0);
623 case BIO_DELETE:
624 /* We do not allow deleting our hot spots */
625 return (EPERM);
626 case BIO_WRITE:
627 g_call_me(g_bsd_hotwrite, bp);
628 return (EJUSTRETURN);
629 case BIO_GETATTR:
630 case BIO_SETATTR:
631 break;
632 default:
633 KASSERT(0 == 1, ("Unknown bio_cmd in g_bsd_start (%d)",
634 bp->bio_cmd));
635 }
636
637 /* We only handle ioctl(2) requests of the right format. */
638 if (strcmp(bp->bio_attribute, "GEOM::ioctl"))
639 return (0);
640 else if (bp->bio_length != sizeof(*gio))
641 return (0);
642
643 /* Get hold of the ioctl parameters. */
644 gio = (struct g_ioctl *)bp->bio_data;
645
646 switch (gio->cmd) {
647 case DIOCGDINFO:
648 /* Return a copy of the disklabel to userland. */
649 bcopy(&ms->inram, gio->data, sizeof(ms->inram));
650 g_io_deliver(bp, 0);
651 return (1);
652 case DIOCSDINFO:
653 case DIOCWDINFO:
654 /*
655 * These we cannot do without the topology lock and some
656 * some I/O requests. Ask the event-handler to schedule
657 * us in a less restricted environment.
658 */
659 error = g_call_me(g_bsd_ioctl, bp);
660 if (error)
661 g_io_deliver(bp, error);
662 /*
663 * We must return non-zero to indicate that we will deal
664 * with this bio, even though we have not done so yet.
665 */
666 return (1);
667 default:
668 return (0);
669 }
670}
671
672/*
673 * Dump configuration information in XML format.
674 * Notice that the function is called once for the geom and once for each
675 * consumer and provider. We let g_slice_dumpconf() do most of the work.
676 */
677static void
| 570 - (bp->bio_offset + gsl->offset);
571 g_bsd_ledec_disklabel(p, &fake.ondisk);
572
573 ondisk2inram(&fake);
574 if (g_bsd_checklabel(&fake.inram)) {
575 g_io_deliver(bp, EPERM);
576 return;
577 }
578 if (g_bsd_lesum(&fake.ondisk, p) != 0) {
579 g_io_deliver(bp, EPERM);
580 return;
581 }
582 g_topology_unlock();
583 error = g_bsd_modify(gp, &fake.inram); /* May pick up topology. */
584 if (error) {
585 g_io_deliver(bp, EPERM);
586 g_topology_lock();
587 return;
588 }
589 /* Update our copy of the disklabel. */
590 ms->inram = fake.inram;
591 inram2ondisk(ms);
592 g_bsd_leenc_disklabel(p, &ms->ondisk);
593 g_slice_finish_hot(bp);
594}
595
596/*-
597 * This start routine is only called for non-trivial requests, all the
598 * trivial ones are handled autonomously by the slice code.
599 * For requests we handle here, we must call the g_io_deliver() on the
600 * bio, and return non-zero to indicate to the slice code that we did so.
601 * This code executes in the "DOWN" I/O path, this means:
602 * * No sleeping.
603 * * Don't grab the topology lock.
604 * * Don't call biowait, g_getattr(), g_setattr() or g_read_data()
605 */
606
607static int
608g_bsd_start(struct bio *bp)
609{
610 struct g_geom *gp;
611 struct g_bsd_softc *ms;
612 struct g_slicer *gsp;
613 struct g_ioctl *gio;
614 int error;
615
616 gp = bp->bio_to->geom;
617 gsp = gp->softc;
618 ms = gsp->softc;
619 switch(bp->bio_cmd) {
620 case BIO_READ:
621 /* We allow reading of our hot spots */
622 return (0);
623 case BIO_DELETE:
624 /* We do not allow deleting our hot spots */
625 return (EPERM);
626 case BIO_WRITE:
627 g_call_me(g_bsd_hotwrite, bp);
628 return (EJUSTRETURN);
629 case BIO_GETATTR:
630 case BIO_SETATTR:
631 break;
632 default:
633 KASSERT(0 == 1, ("Unknown bio_cmd in g_bsd_start (%d)",
634 bp->bio_cmd));
635 }
636
637 /* We only handle ioctl(2) requests of the right format. */
638 if (strcmp(bp->bio_attribute, "GEOM::ioctl"))
639 return (0);
640 else if (bp->bio_length != sizeof(*gio))
641 return (0);
642
643 /* Get hold of the ioctl parameters. */
644 gio = (struct g_ioctl *)bp->bio_data;
645
646 switch (gio->cmd) {
647 case DIOCGDINFO:
648 /* Return a copy of the disklabel to userland. */
649 bcopy(&ms->inram, gio->data, sizeof(ms->inram));
650 g_io_deliver(bp, 0);
651 return (1);
652 case DIOCSDINFO:
653 case DIOCWDINFO:
654 /*
655 * These we cannot do without the topology lock and some
656 * some I/O requests. Ask the event-handler to schedule
657 * us in a less restricted environment.
658 */
659 error = g_call_me(g_bsd_ioctl, bp);
660 if (error)
661 g_io_deliver(bp, error);
662 /*
663 * We must return non-zero to indicate that we will deal
664 * with this bio, even though we have not done so yet.
665 */
666 return (1);
667 default:
668 return (0);
669 }
670}
671
672/*
673 * Dump configuration information in XML format.
674 * Notice that the function is called once for the geom and once for each
675 * consumer and provider. We let g_slice_dumpconf() do most of the work.
676 */
677static void
|
678g_bsd_dumpconf(struct sbuf *sb, char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
| 678g_bsd_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
|
679{
680 struct g_bsd_softc *ms;
681 struct g_slicer *gsp;
682
683 gsp = gp->softc;
684 ms = gsp->softc;
685 g_slice_dumpconf(sb, indent, gp, cp, pp);
686 if (indent != NULL && pp == NULL && cp == NULL) {
687 sbuf_printf(sb, "%s<labeloffset>%jd</labeloffset>\n",
688 indent, (intmax_t)ms->labeloffset);
689 sbuf_printf(sb, "%s<rawoffset>%jd</rawoffset>\n",
690 indent, (intmax_t)ms->rawoffset);
691 sbuf_printf(sb, "%s<mbroffset>%jd</mbroffset>\n",
692 indent, (intmax_t)ms->mbroffset);
693 }
694}
695
696/*
697 * The taste function is called from the event-handler, with the topology
698 * lock already held and a provider to examine. The flags are unused.
699 *
700 * If flags == G_TF_NORMAL, the idea is to take a bite of the provider and
701 * if we find valid, consistent magic on it, build a geom on it.
702 * any magic bits which indicate that we should automatically put a BSD
703 * geom on it.
704 *
705 * There may be cases where the operator would like to put a BSD-geom on
706 * providers which do not meet all of the requirements. This can be done
707 * by instead passing the G_TF_INSIST flag, which will override these
708 * checks.
709 *
710 * The final flags value is G_TF_TRANSPARENT, which instructs the method
711 * to put a geom on top of the provider and configure it to be as transparent
712 * as possible. This is not really relevant to the BSD method and therefore
713 * not implemented here.
714 */
715
716static struct g_geom *
717g_bsd_taste(struct g_class *mp, struct g_provider *pp, int flags)
718{
719 struct g_geom *gp;
720 struct g_consumer *cp;
721 int error, i;
722 struct g_bsd_softc *ms;
723 struct disklabel *dl;
724 u_int secsize;
725 struct g_slicer *gsp;
726
727 g_trace(G_T_TOPOLOGY, "bsd_taste(%s,%s)", mp->name, pp->name);
728 g_topology_assert();
729
730 /* We don't implement transparent inserts. */
731 if (flags == G_TF_TRANSPARENT)
732 return (NULL);
733
734 /*
735 * The BSD-method will not automatically configure itself recursively
736 * Note that it is legal to examine the class-name of our provider,
737 * nothing else should ever be examined inside the provider.
738 */
739 if (flags == G_TF_NORMAL &&
740 !strcmp(pp->geom->class->name, BSD_CLASS_NAME))
741 return (NULL);
742
743 /*
744 * BSD labels are a subclass of the general "slicing" topology so
745 * a lot of the work can be done by the common "slice" code.
746 * Create a geom with space for MAXPARTITIONS providers, one consumer
747 * and a softc structure for us. Specify the provider to attach
748 * the consumer to and our "start" routine for special requests.
749 * The provider is opened with mode (1,0,0) so we can do reads
750 * from it.
751 */
752 gp = g_slice_new(mp, MAXPARTITIONS, pp, &cp, &ms,
753 sizeof(*ms), g_bsd_start);
754 if (gp == NULL)
755 return (NULL);
756
757 /*
758 * Now that we have attached to and opened our provider, we do
759 * not need the topology lock until we change the topology again
760 * next time.
761 */
762 g_topology_unlock();
763
764 /*
765 * Fill in the optional details, in our case we have a dumpconf
766 * routine which the "slice" code should call at the right time
767 */
768 gp->dumpconf = g_bsd_dumpconf;
769
770 /* Get the geom_slicer softc from the geom. */
771 gsp = gp->softc;
772
773 /*
774 * The do...while loop here allows us to have multiple escapes
775 * using a simple "break". This improves code clarity without
776 * ending up in deep nesting and without using goto or come from.
777 */
778 do {
779 /*
780 * If the provider is an MBR we will only auto attach
781 * to type 165 slices in the G_TF_NORMAL case. We will
782 * attach to any other type (BSD was handles above)
783 */
784 error = g_getattr("MBR::type", cp, &i);
785 if (!error) {
786 if (i != 165 && flags == G_TF_NORMAL)
787 break;
788 error = g_getattr("MBR::offset", cp, &ms->mbroffset);
789 if (error)
790 break;
791 }
792
793 /* Same thing if we are inside a PC98 */
794 error = g_getattr("PC98::type", cp, &i);
795 if (!error) {
796 if (i != 0xc494 && flags == G_TF_NORMAL)
797 break;
798 error = g_getattr("PC98::offset", cp, &ms->mbroffset);
799 if (error)
800 break;
801 }
802
803 /* Get sector size, we need it to read data. */
804 secsize = cp->provider->sectorsize;
805 if (secsize < 512)
806 break;
807
808 /* First look for a label at the start of the second sector. */
809 error = g_bsd_try(gp, gsp, cp, secsize, ms, secsize);
810
811 /* Next, look for alpha labels */
812 if (error)
813 error = g_bsd_try(gp, gsp, cp, secsize, ms,
814 ALPHA_LABEL_OFFSET);
815
816 /* If we didn't find a label, punt. */
817 if (error)
818 break;
819
820 /*
821 * Process the found disklabel, and modify our "slice"
822 * instance to match it, if possible.
823 */
824 dl = &ms->inram;
825 error = g_bsd_modify(gp, dl); /* Picks up topology lock. */
826 if (!error)
827 g_topology_unlock();
828 break;
829 } while (0);
830
831 /* Success of failure, we can close our provider now. */
832 g_topology_lock();
833 error = g_access_rel(cp, -1, 0, 0);
834
835 /* If we have configured any providers, return the new geom. */
836 if (gsp->nprovider > 0)
837 return (gp);
838 /*
839 * ...else push the "self-destruct" button, by spoiling our own
840 * consumer. This triggers a call to g_std_spoiled which will
841 * dismantle what was setup.
842 */
843 g_std_spoiled(cp);
844 return (NULL);
845}
846
847/* Finally, register with GEOM infrastructure. */
848static struct g_class g_bsd_class = {
849 BSD_CLASS_NAME,
850 g_bsd_taste,
851 NULL,
852 G_CLASS_INITIALIZER
853};
854
855DECLARE_GEOM_CLASS(g_bsd_class, g_bsd);
| 679{
680 struct g_bsd_softc *ms;
681 struct g_slicer *gsp;
682
683 gsp = gp->softc;
684 ms = gsp->softc;
685 g_slice_dumpconf(sb, indent, gp, cp, pp);
686 if (indent != NULL && pp == NULL && cp == NULL) {
687 sbuf_printf(sb, "%s<labeloffset>%jd</labeloffset>\n",
688 indent, (intmax_t)ms->labeloffset);
689 sbuf_printf(sb, "%s<rawoffset>%jd</rawoffset>\n",
690 indent, (intmax_t)ms->rawoffset);
691 sbuf_printf(sb, "%s<mbroffset>%jd</mbroffset>\n",
692 indent, (intmax_t)ms->mbroffset);
693 }
694}
695
696/*
697 * The taste function is called from the event-handler, with the topology
698 * lock already held and a provider to examine. The flags are unused.
699 *
700 * If flags == G_TF_NORMAL, the idea is to take a bite of the provider and
701 * if we find valid, consistent magic on it, build a geom on it.
702 * any magic bits which indicate that we should automatically put a BSD
703 * geom on it.
704 *
705 * There may be cases where the operator would like to put a BSD-geom on
706 * providers which do not meet all of the requirements. This can be done
707 * by instead passing the G_TF_INSIST flag, which will override these
708 * checks.
709 *
710 * The final flags value is G_TF_TRANSPARENT, which instructs the method
711 * to put a geom on top of the provider and configure it to be as transparent
712 * as possible. This is not really relevant to the BSD method and therefore
713 * not implemented here.
714 */
715
716static struct g_geom *
717g_bsd_taste(struct g_class *mp, struct g_provider *pp, int flags)
718{
719 struct g_geom *gp;
720 struct g_consumer *cp;
721 int error, i;
722 struct g_bsd_softc *ms;
723 struct disklabel *dl;
724 u_int secsize;
725 struct g_slicer *gsp;
726
727 g_trace(G_T_TOPOLOGY, "bsd_taste(%s,%s)", mp->name, pp->name);
728 g_topology_assert();
729
730 /* We don't implement transparent inserts. */
731 if (flags == G_TF_TRANSPARENT)
732 return (NULL);
733
734 /*
735 * The BSD-method will not automatically configure itself recursively
736 * Note that it is legal to examine the class-name of our provider,
737 * nothing else should ever be examined inside the provider.
738 */
739 if (flags == G_TF_NORMAL &&
740 !strcmp(pp->geom->class->name, BSD_CLASS_NAME))
741 return (NULL);
742
743 /*
744 * BSD labels are a subclass of the general "slicing" topology so
745 * a lot of the work can be done by the common "slice" code.
746 * Create a geom with space for MAXPARTITIONS providers, one consumer
747 * and a softc structure for us. Specify the provider to attach
748 * the consumer to and our "start" routine for special requests.
749 * The provider is opened with mode (1,0,0) so we can do reads
750 * from it.
751 */
752 gp = g_slice_new(mp, MAXPARTITIONS, pp, &cp, &ms,
753 sizeof(*ms), g_bsd_start);
754 if (gp == NULL)
755 return (NULL);
756
757 /*
758 * Now that we have attached to and opened our provider, we do
759 * not need the topology lock until we change the topology again
760 * next time.
761 */
762 g_topology_unlock();
763
764 /*
765 * Fill in the optional details, in our case we have a dumpconf
766 * routine which the "slice" code should call at the right time
767 */
768 gp->dumpconf = g_bsd_dumpconf;
769
770 /* Get the geom_slicer softc from the geom. */
771 gsp = gp->softc;
772
773 /*
774 * The do...while loop here allows us to have multiple escapes
775 * using a simple "break". This improves code clarity without
776 * ending up in deep nesting and without using goto or come from.
777 */
778 do {
779 /*
780 * If the provider is an MBR we will only auto attach
781 * to type 165 slices in the G_TF_NORMAL case. We will
782 * attach to any other type (BSD was handles above)
783 */
784 error = g_getattr("MBR::type", cp, &i);
785 if (!error) {
786 if (i != 165 && flags == G_TF_NORMAL)
787 break;
788 error = g_getattr("MBR::offset", cp, &ms->mbroffset);
789 if (error)
790 break;
791 }
792
793 /* Same thing if we are inside a PC98 */
794 error = g_getattr("PC98::type", cp, &i);
795 if (!error) {
796 if (i != 0xc494 && flags == G_TF_NORMAL)
797 break;
798 error = g_getattr("PC98::offset", cp, &ms->mbroffset);
799 if (error)
800 break;
801 }
802
803 /* Get sector size, we need it to read data. */
804 secsize = cp->provider->sectorsize;
805 if (secsize < 512)
806 break;
807
808 /* First look for a label at the start of the second sector. */
809 error = g_bsd_try(gp, gsp, cp, secsize, ms, secsize);
810
811 /* Next, look for alpha labels */
812 if (error)
813 error = g_bsd_try(gp, gsp, cp, secsize, ms,
814 ALPHA_LABEL_OFFSET);
815
816 /* If we didn't find a label, punt. */
817 if (error)
818 break;
819
820 /*
821 * Process the found disklabel, and modify our "slice"
822 * instance to match it, if possible.
823 */
824 dl = &ms->inram;
825 error = g_bsd_modify(gp, dl); /* Picks up topology lock. */
826 if (!error)
827 g_topology_unlock();
828 break;
829 } while (0);
830
831 /* Success of failure, we can close our provider now. */
832 g_topology_lock();
833 error = g_access_rel(cp, -1, 0, 0);
834
835 /* If we have configured any providers, return the new geom. */
836 if (gsp->nprovider > 0)
837 return (gp);
838 /*
839 * ...else push the "self-destruct" button, by spoiling our own
840 * consumer. This triggers a call to g_std_spoiled which will
841 * dismantle what was setup.
842 */
843 g_std_spoiled(cp);
844 return (NULL);
845}
846
847/* Finally, register with GEOM infrastructure. */
848static struct g_class g_bsd_class = {
849 BSD_CLASS_NAME,
850 g_bsd_taste,
851 NULL,
852 G_CLASS_INITIALIZER
853};
854
855DECLARE_GEOM_CLASS(g_bsd_class, g_bsd);
|