xref: /dragonfly/sbin/hammer/blockmap.c (revision a4c31683)
1 /*
2  * Copyright (c) 2008 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Matthew Dillon <dillon@backplane.com>
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  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * $DragonFly: src/sbin/hammer/blockmap.c,v 1.2 2008/06/17 04:03:38 dillon Exp $
35  */
36 
37 #include "hammer_util.h"
38 
39 /*
40  * Allocate big-blocks using our poor-man's volume->vol_free_off.
41  * We are bootstrapping the freemap itself and cannot update it yet.
42  */
43 hammer_off_t
44 bootstrap_bigblock(volume_info_t volume)
45 {
46 	hammer_off_t result_offset;
47 
48 	assert_volume_offset(volume);
49 	result_offset = volume->vol_free_off;
50 
51 	volume->vol_free_off += HAMMER_BIGBLOCK_SIZE;
52 
53 	return(result_offset);
54 }
55 
56 /*
57  * Allocate a big-block for zone-3 for UNDO/REDO FIFO.
58  */
59 hammer_off_t
60 alloc_undo_bigblock(volume_info_t volume)
61 {
62 	hammer_blockmap_t freemap;
63 	buffer_info_t buffer1 = NULL;
64 	buffer_info_t buffer2 = NULL;
65 	hammer_blockmap_layer1_t layer1;
66 	hammer_blockmap_layer2_t layer2;
67 	hammer_off_t layer1_offset;
68 	hammer_off_t layer2_offset;
69 	hammer_off_t result_offset;
70 
71 	/* Only root volume needs formatting */
72 	assert(volume->vol_no == HAMMER_ROOT_VOLNO);
73 
74 	result_offset = bootstrap_bigblock(volume);
75 	freemap = &volume->ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
76 
77 	/*
78 	 * Dive layer 1.
79 	 */
80 	layer1_offset = freemap->phys_offset +
81 			HAMMER_BLOCKMAP_LAYER1_OFFSET(result_offset);
82 	layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
83 	assert(layer1->phys_offset != HAMMER_BLOCKMAP_UNAVAIL);
84 	--layer1->blocks_free;
85 	hammer_crc_set_layer1(HammerVersion, layer1);
86 	buffer1->cache.modified = 1;
87 
88 	/*
89 	 * Dive layer 2, each entry represents a big-block.
90 	 */
91 	layer2_offset = layer1->phys_offset +
92 			HAMMER_BLOCKMAP_LAYER2_OFFSET(result_offset);
93 	layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
94 	assert(layer2->zone == 0);
95 	layer2->zone = HAMMER_ZONE_UNDO_INDEX;
96 	layer2->append_off = HAMMER_BIGBLOCK_SIZE;
97 	layer2->bytes_free = 0;
98 	hammer_crc_set_layer2(HammerVersion, layer2);
99 	buffer2->cache.modified = 1;
100 
101 	--volume->ondisk->vol0_stat_freebigblocks;
102 
103 	rel_buffer(buffer1);
104 	rel_buffer(buffer2);
105 
106 	return(result_offset);
107 }
108 
109 /*
110  * Allocate a chunk of data out of a blockmap.  This is a simplified
111  * version which uses next_offset as a simple allocation iterator.
112  */
113 void *
114 alloc_blockmap(int zone, int bytes, hammer_off_t *result_offp,
115 	       buffer_info_t *bufferp)
116 {
117 	volume_info_t volume;
118 	hammer_blockmap_t blockmap;
119 	hammer_blockmap_t freemap;
120 	buffer_info_t buffer1 = NULL;
121 	buffer_info_t buffer2 = NULL;
122 	hammer_blockmap_layer1_t layer1;
123 	hammer_blockmap_layer2_t layer2;
124 	hammer_off_t tmp_offset;
125 	hammer_off_t layer1_offset;
126 	hammer_off_t layer2_offset;
127 	void *ptr;
128 
129 	volume = get_root_volume();
130 
131 	blockmap = &volume->ondisk->vol0_blockmap[zone];
132 	freemap = &volume->ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
133 	assert(HAMMER_ZONE_DECODE(blockmap->next_offset) == zone);
134 
135 	/*
136 	 * Alignment and buffer-boundary issues.  If the allocation would
137 	 * cross a buffer boundary we have to skip to the next buffer.
138 	 */
139 	bytes = HAMMER_DATA_DOALIGN(bytes);
140 	assert(bytes > 0 && bytes <= HAMMER_BUFSIZE);  /* not HAMMER_XBUFSIZE */
141 	assert(hammer_is_index_record(zone));
142 
143 again:
144 	assert(blockmap->next_offset != HAMMER_ZONE_ENCODE(zone + 1, 0));
145 
146 	tmp_offset = blockmap->next_offset + bytes - 1;
147 	if ((blockmap->next_offset ^ tmp_offset) & ~HAMMER_BUFMASK64)
148 		blockmap->next_offset = tmp_offset & ~HAMMER_BUFMASK64;
149 
150 	/*
151 	 * Dive layer 1.
152 	 */
153 	layer1_offset = freemap->phys_offset +
154 			HAMMER_BLOCKMAP_LAYER1_OFFSET(blockmap->next_offset);
155 	layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
156 	assert(layer1->phys_offset != HAMMER_BLOCKMAP_UNAVAIL);
157 	assert(!((blockmap->next_offset & HAMMER_BIGBLOCK_MASK) == 0 &&
158 		layer1->blocks_free == 0));
159 
160 	/*
161 	 * Dive layer 2, each entry represents a big-block.
162 	 */
163 	layer2_offset = layer1->phys_offset +
164 			HAMMER_BLOCKMAP_LAYER2_OFFSET(blockmap->next_offset);
165 	layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
166 
167 	if (layer2->zone == HAMMER_ZONE_UNAVAIL_INDEX) {
168 		errx(1, "alloc_blockmap: layer2 ran out of space!");
169 		/* not reached */
170 	}
171 
172 	/*
173 	 * If we are entering a new big-block assign ownership to our
174 	 * zone.  If the big-block is owned by another zone skip it.
175 	 */
176 	if (layer2->zone == 0) {
177 		--layer1->blocks_free;
178 		hammer_crc_set_layer1(HammerVersion, layer1);
179 		layer2->zone = zone;
180 		--volume->ondisk->vol0_stat_freebigblocks;
181 		assert(layer2->bytes_free == HAMMER_BIGBLOCK_SIZE);
182 		assert(layer2->append_off == 0);
183 	}
184 	if (layer2->zone != zone) {
185 		blockmap->next_offset =
186 			HAMMER_ZONE_LAYER2_NEXT_OFFSET(blockmap->next_offset);
187 		goto again;
188 	}
189 
190 	assert(layer2->append_off ==
191 		(blockmap->next_offset & HAMMER_BIGBLOCK_MASK));
192 	layer2->bytes_free -= bytes;
193 	*result_offp = blockmap->next_offset;
194 	blockmap->next_offset += bytes;
195 	layer2->append_off = (int)blockmap->next_offset & HAMMER_BIGBLOCK_MASK;
196 	hammer_crc_set_layer2(HammerVersion, layer2);
197 
198 	ptr = get_buffer_data(*result_offp, bufferp, 0);
199 	(*bufferp)->cache.modified = 1;
200 
201 	buffer1->cache.modified = 1;
202 	buffer2->cache.modified = 1;
203 
204 	rel_buffer(buffer1);
205 	rel_buffer(buffer2);
206 	return(ptr);
207 }
208 
209 hammer_off_t
210 blockmap_lookup(hammer_off_t zone_offset, int *errorp)
211 {
212 	return(blockmap_lookup_save(zone_offset, NULL, NULL, errorp));
213 }
214 
215 hammer_off_t
216 blockmap_lookup_save(hammer_off_t zone_offset,
217 		hammer_blockmap_layer1_t save_layer1,
218 		hammer_blockmap_layer2_t save_layer2,
219 		int *errorp)
220 {
221 	volume_info_t root_volume = NULL;
222 	hammer_volume_ondisk_t ondisk;
223 	hammer_blockmap_t blockmap;
224 	hammer_blockmap_t freemap;
225 	hammer_blockmap_layer1_t layer1;
226 	hammer_blockmap_layer2_t layer2;
227 	buffer_info_t buffer1 = NULL;
228 	buffer_info_t buffer2 = NULL;
229 	hammer_off_t layer1_offset;
230 	hammer_off_t layer2_offset;
231 	hammer_off_t result_offset = HAMMER_OFF_BAD;;
232 	int zone;
233 	int error = 0;
234 
235 	if (save_layer1)
236 		bzero(save_layer1, sizeof(*save_layer1));
237 	if (save_layer2)
238 		bzero(save_layer2, sizeof(*save_layer2));
239 
240 	zone = HAMMER_ZONE_DECODE(zone_offset);
241 
242 	if (zone <= HAMMER_ZONE_RAW_VOLUME_INDEX) {
243 		error = -1;
244 		goto done;
245 	}
246 	if (zone >= HAMMER_MAX_ZONES) {
247 		error = -2;
248 		goto done;
249 	}
250 
251 	root_volume = get_root_volume();
252 	ondisk = root_volume->ondisk;
253 	blockmap = &ondisk->vol0_blockmap[zone];
254 
255 	/*
256 	 * Handle blockmap offset translations.
257 	 */
258 	if (hammer_is_index_record(zone)) {
259 		result_offset = hammer_xlate_to_zone2(zone_offset);
260 	} else if (zone == HAMMER_ZONE_UNDO_INDEX) {
261 		if (zone_offset >= blockmap->alloc_offset) {
262 			error = -3;
263 			goto done;
264 		}
265 		result_offset = hammer_xlate_to_undo(ondisk, zone_offset);
266 	} else {
267 		/* assert(zone == HAMMER_ZONE_RAW_BUFFER_INDEX); */
268 		result_offset = zone_offset;
269 	}
270 
271 	/*
272 	 * The blockmap should match the requested zone (else the volume
273 	 * header is mashed).
274 	 */
275 	if (hammer_is_index_record(zone) &&
276 	    HAMMER_ZONE_DECODE(blockmap->alloc_offset) != zone) {
277 		error = -4;
278 		goto done;
279 	}
280 
281 	/*
282 	 * Validate that the big-block is assigned to the zone.  Also
283 	 * assign save_layer{1,2} if not NULL.
284 	 */
285 	freemap = &ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
286 
287 	/*
288 	 * Dive layer 1.
289 	 */
290 	layer1_offset = freemap->phys_offset +
291 			HAMMER_BLOCKMAP_LAYER1_OFFSET(result_offset);
292 	layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
293 
294 	if (layer1 == NULL) {
295 		error = -5;
296 		goto done;
297 	}
298 	if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL) {
299 		error = -6;
300 		goto done;
301 	}
302 	if (save_layer1)
303 		*save_layer1 = *layer1;
304 
305 	/*
306 	 * Dive layer 2, each entry represents a big-block.
307 	 */
308 	layer2_offset = layer1->phys_offset +
309 			HAMMER_BLOCKMAP_LAYER2_OFFSET(result_offset);
310 	layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
311 
312 	if (layer2 == NULL) {
313 		error = -7;
314 		goto done;
315 	}
316 	if (layer2->zone != zone) {
317 		error = -8;
318 		goto done;
319 	}
320 	if (save_layer2)
321 		*save_layer2 = *layer2;
322 
323 done:
324 	rel_buffer(buffer1);
325 	rel_buffer(buffer2);
326 
327 	if (errorp)
328 		*errorp = error;
329 
330 	return(result_offset);
331 }
332 
333