1 /* $NetBSD: merge.c,v 1.1.1.1 2008/12/22 00:18:07 haad Exp $ */
2
3 /*
4 * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
5 * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
6 *
7 * This file is part of LVM2.
8 *
9 * This copyrighted material is made available to anyone wishing to use,
10 * modify, copy, or redistribute it subject to the terms and conditions
11 * of the GNU Lesser General Public License v.2.1.
12 *
13 * You should have received a copy of the GNU Lesser General Public License
14 * along with this program; if not, write to the Free Software Foundation,
15 * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
16 */
17
18 #include "lib.h"
19 #include "metadata.h"
20 #include "toolcontext.h"
21 #include "lv_alloc.h"
22 #include "pv_alloc.h"
23 #include "str_list.h"
24 #include "segtype.h"
25
26 /*
27 * Attempt to merge two adjacent segments.
28 * Currently only supports striped segments on AREA_PV.
29 * Returns success if successful, in which case 'first'
30 * gets adjusted to contain both areas.
31 */
_merge(struct lv_segment * first,struct lv_segment * second)32 static int _merge(struct lv_segment *first, struct lv_segment *second)
33 {
34 if (!first || !second || first->segtype != second->segtype ||
35 !first->segtype->ops->merge_segments) return 0;
36
37 return first->segtype->ops->merge_segments(first, second);
38 }
39
lv_merge_segments(struct logical_volume * lv)40 int lv_merge_segments(struct logical_volume *lv)
41 {
42 struct dm_list *segh, *t;
43 struct lv_segment *current, *prev = NULL;
44
45 if (lv->status & LOCKED || lv->status & PVMOVE)
46 return 1;
47
48 dm_list_iterate_safe(segh, t, &lv->segments) {
49 current = dm_list_item(segh, struct lv_segment);
50
51 if (_merge(prev, current))
52 dm_list_del(¤t->list);
53 else
54 prev = current;
55 }
56
57 return 1;
58 }
59
60 /*
61 * Verify that an LV's segments are consecutive, complete and don't overlap.
62 */
check_lv_segments(struct logical_volume * lv,int complete_vg)63 int check_lv_segments(struct logical_volume *lv, int complete_vg)
64 {
65 struct lv_segment *seg, *seg2;
66 uint32_t le = 0;
67 unsigned seg_count = 0, seg_found;
68 int r = 1;
69 uint32_t area_multiplier, s;
70 struct seg_list *sl;
71
72 dm_list_iterate_items(seg, &lv->segments) {
73 seg_count++;
74 if (seg->le != le) {
75 log_error("LV %s invalid: segment %u should begin at "
76 "LE %" PRIu32 " (found %" PRIu32 ").",
77 lv->name, seg_count, le, seg->le);
78 r = 0;
79 }
80
81 area_multiplier = segtype_is_striped(seg->segtype) ?
82 seg->area_count : 1;
83
84 if (seg->area_len * area_multiplier != seg->len) {
85 log_error("LV %s: segment %u has inconsistent "
86 "area_len %u",
87 lv->name, seg_count, seg->area_len);
88 r = 0;
89 }
90
91 if (complete_vg && seg->log_lv) {
92 if (!seg_is_mirrored(seg)) {
93 log_error("LV %s: segment %u has log LV but "
94 "is not mirrored",
95 lv->name, seg_count);
96 r = 0;
97 }
98
99 if (!(seg->log_lv->status & MIRROR_LOG)) {
100 log_error("LV %s: segment %u log LV %s is not "
101 "a mirror log",
102 lv->name, seg_count, seg->log_lv->name);
103 r = 0;
104 }
105
106 if (!(seg2 = first_seg(seg->log_lv)) ||
107 find_mirror_seg(seg2) != seg) {
108 log_error("LV %s: segment %u log LV does not "
109 "point back to mirror segment",
110 lv->name, seg_count);
111 r = 0;
112 }
113 }
114
115 if (complete_vg && seg->status & MIRROR_IMAGE) {
116 if (!find_mirror_seg(seg) ||
117 !seg_is_mirrored(find_mirror_seg(seg))) {
118 log_error("LV %s: segment %u mirror image "
119 "is not mirrored",
120 lv->name, seg_count);
121 r = 0;
122 }
123 }
124
125 if (seg_is_snapshot(seg)) {
126 if (seg->cow && seg->cow == seg->origin) {
127 log_error("LV %s: segment %u has same LV %s for "
128 "both origin and snapshot",
129 lv->name, seg_count, seg->cow->name);
130 r = 0;
131 }
132 }
133
134 for (s = 0; s < seg->area_count; s++) {
135 if (seg_type(seg, s) == AREA_UNASSIGNED) {
136 log_error("LV %s: segment %u has unassigned "
137 "area %u.",
138 lv->name, seg_count, s);
139 r = 0;
140 } else if (seg_type(seg, s) == AREA_PV) {
141 if (!seg_pvseg(seg, s) ||
142 seg_pvseg(seg, s)->lvseg != seg ||
143 seg_pvseg(seg, s)->lv_area != s) {
144 log_error("LV %s: segment %u has "
145 "inconsistent PV area %u",
146 lv->name, seg_count, s);
147 r = 0;
148 }
149 } else {
150 if (!seg_lv(seg, s) ||
151 seg_lv(seg, s)->vg != lv->vg ||
152 seg_lv(seg, s) == lv) {
153 log_error("LV %s: segment %u has "
154 "inconsistent LV area %u",
155 lv->name, seg_count, s);
156 r = 0;
157 }
158
159 if (complete_vg && seg_lv(seg, s) &&
160 (seg_lv(seg, s)->status & MIRROR_IMAGE) &&
161 (!(seg2 = find_seg_by_le(seg_lv(seg, s),
162 seg_le(seg, s))) ||
163 find_mirror_seg(seg2) != seg)) {
164 log_error("LV %s: segment %u mirror "
165 "image %u missing mirror ptr",
166 lv->name, seg_count, s);
167 r = 0;
168 }
169
170 /* FIXME I don't think this ever holds?
171 if (seg_le(seg, s) != le) {
172 log_error("LV %s: segment %u has "
173 "inconsistent LV area %u "
174 "size",
175 lv->name, seg_count, s);
176 r = 0;
177 }
178 */
179 seg_found = 0;
180 dm_list_iterate_items(sl, &seg_lv(seg, s)->segs_using_this_lv)
181 if (sl->seg == seg)
182 seg_found++;
183 if (!seg_found) {
184 log_error("LV %s segment %d uses LV %s,"
185 " but missing ptr from %s to %s",
186 lv->name, seg_count,
187 seg_lv(seg, s)->name,
188 seg_lv(seg, s)->name, lv->name);
189 r = 0;
190 } else if (seg_found > 1) {
191 log_error("LV %s has duplicated links "
192 "to LV %s segment %d",
193 seg_lv(seg, s)->name,
194 lv->name, seg_count);
195 r = 0;
196 }
197 }
198 }
199
200 le += seg->len;
201 }
202
203 dm_list_iterate_items(sl, &lv->segs_using_this_lv) {
204 seg = sl->seg;
205 seg_found = 0;
206 for (s = 0; s < seg->area_count; s++) {
207 if (seg_type(seg, s) != AREA_LV)
208 continue;
209 if (lv == seg_lv(seg, s))
210 seg_found++;
211 }
212 if (seg->log_lv == lv)
213 seg_found++;
214 if (!seg_found) {
215 log_error("LV %s is used by LV %s:%" PRIu32 "-%" PRIu32
216 ", but missing ptr from %s to %s",
217 lv->name, seg->lv->name, seg->le,
218 seg->le + seg->len - 1,
219 seg->lv->name, lv->name);
220 r = 0;
221 } else if (seg_found != sl->count) {
222 log_error("Reference count mismatch: LV %s has %d "
223 "links to LV %s:%" PRIu32 "-%" PRIu32
224 ", which has %d links",
225 lv->name, sl->count, seg->lv->name, seg->le,
226 seg->le + seg->len - 1, seg_found);
227 r = 0;
228 }
229
230 seg_found = 0;
231 dm_list_iterate_items(seg2, &seg->lv->segments)
232 if (sl->seg == seg2) {
233 seg_found++;
234 break;
235 }
236 if (!seg_found) {
237 log_error("LV segment %s:%" PRIu32 "-%" PRIu32
238 "is incorrectly listed as being used by LV %s",
239 seg->lv->name, seg->le, seg->le + seg->len - 1,
240 lv->name);
241 r = 0;
242 }
243 }
244
245 if (le != lv->le_count) {
246 log_error("LV %s: inconsistent LE count %u != %u",
247 lv->name, le, lv->le_count);
248 r = 0;
249 }
250
251 return r;
252 }
253
254 /*
255 * Split the supplied segment at the supplied logical extent
256 * NB Use LE numbering that works across stripes PV1: 0,2,4 PV2: 1,3,5 etc.
257 */
_lv_split_segment(struct logical_volume * lv,struct lv_segment * seg,uint32_t le)258 static int _lv_split_segment(struct logical_volume *lv, struct lv_segment *seg,
259 uint32_t le)
260 {
261 struct lv_segment *split_seg;
262 uint32_t s;
263 uint32_t offset = le - seg->le;
264 uint32_t area_offset;
265
266 if (!seg_can_split(seg)) {
267 log_error("Unable to split the %s segment at LE %" PRIu32
268 " in LV %s", seg->segtype->name, le, lv->name);
269 return 0;
270 }
271
272 /* Clone the existing segment */
273 if (!(split_seg = alloc_lv_segment(lv->vg->cmd->mem, seg->segtype,
274 seg->lv, seg->le, seg->len,
275 seg->status, seg->stripe_size,
276 seg->log_lv,
277 seg->area_count, seg->area_len,
278 seg->chunk_size, seg->region_size,
279 seg->extents_copied))) {
280 log_error("Couldn't allocate cloned LV segment.");
281 return 0;
282 }
283
284 if (!str_list_dup(lv->vg->cmd->mem, &split_seg->tags, &seg->tags)) {
285 log_error("LV segment tags duplication failed");
286 return 0;
287 }
288
289 /* In case of a striped segment, the offset has to be / stripes */
290 area_offset = offset;
291 if (seg_is_striped(seg))
292 area_offset /= seg->area_count;
293
294 split_seg->area_len -= area_offset;
295 seg->area_len = area_offset;
296
297 split_seg->len -= offset;
298 seg->len = offset;
299
300 split_seg->le = seg->le + seg->len;
301
302 /* Adjust the PV mapping */
303 for (s = 0; s < seg->area_count; s++) {
304 seg_type(split_seg, s) = seg_type(seg, s);
305
306 /* Split area at the offset */
307 switch (seg_type(seg, s)) {
308 case AREA_LV:
309 if (!set_lv_segment_area_lv(split_seg, s, seg_lv(seg, s),
310 seg_le(seg, s) + seg->area_len, 0))
311 return_0;
312 log_debug("Split %s:%u[%u] at %u: %s LE %u", lv->name,
313 seg->le, s, le, seg_lv(seg, s)->name,
314 seg_le(split_seg, s));
315 break;
316
317 case AREA_PV:
318 if (!(seg_pvseg(split_seg, s) =
319 assign_peg_to_lvseg(seg_pv(seg, s),
320 seg_pe(seg, s) +
321 seg->area_len,
322 seg_pvseg(seg, s)->len -
323 seg->area_len,
324 split_seg, s)))
325 return_0;
326 log_debug("Split %s:%u[%u] at %u: %s PE %u", lv->name,
327 seg->le, s, le,
328 dev_name(seg_dev(seg, s)),
329 seg_pe(split_seg, s));
330 break;
331
332 case AREA_UNASSIGNED:
333 log_error("Unassigned area %u found in segment", s);
334 return 0;
335 }
336 }
337
338 /* Add split off segment to the list _after_ the original one */
339 dm_list_add_h(&seg->list, &split_seg->list);
340
341 return 1;
342 }
343
344 /*
345 * Ensure there's a segment boundary at the given logical extent
346 */
lv_split_segment(struct logical_volume * lv,uint32_t le)347 int lv_split_segment(struct logical_volume *lv, uint32_t le)
348 {
349 struct lv_segment *seg;
350
351 if (!(seg = find_seg_by_le(lv, le))) {
352 log_error("Segment with extent %" PRIu32 " in LV %s not found",
353 le, lv->name);
354 return 0;
355 }
356
357 /* This is a segment start already */
358 if (le == seg->le)
359 return 1;
360
361 if (!_lv_split_segment(lv, seg, le))
362 return_0;
363
364 if (!vg_validate(lv->vg))
365 return_0;
366
367 return 1;
368 }
369