xref: /dragonfly/sbin/hammer/ondisk.c (revision 73b5ca6b)
1 /*
2  * Copyright (c) 2007 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 
35 #include "hammer_util.h"
36 
37 #include <sys/diskslice.h>
38 #include <sys/diskmbr.h>
39 
40 static void check_volume(volume_info_t volume);
41 static void get_buffer_readahead(buffer_info_t base);
42 static __inline int readhammervol(volume_info_t volume);
43 static __inline int readhammerbuf(buffer_info_t buffer);
44 static __inline int writehammervol(volume_info_t volume);
45 static __inline int writehammerbuf(buffer_info_t buffer);
46 
47 hammer_uuid_t Hammer_FSType;
48 hammer_uuid_t Hammer_FSId;
49 int UseReadBehind = -4;
50 int UseReadAhead = 4;
51 int DebugOpt;
52 uint32_t HammerVersion = -1;
53 
54 TAILQ_HEAD(volume_list, volume_info);
55 static struct volume_list VolList = TAILQ_HEAD_INITIALIZER(VolList);
56 static int valid_hammer_volumes;
57 
58 static __inline
59 int
60 buffer_hash(hammer_off_t zone2_offset)
61 {
62 	int hi;
63 
64 	hi = (int)(zone2_offset / HAMMER_BUFSIZE) & HAMMER_BUFLISTMASK;
65 	return(hi);
66 }
67 
68 static
69 buffer_info_t
70 find_buffer(hammer_off_t zone2_offset)
71 {
72 	volume_info_t volume;
73 	buffer_info_t buffer;
74 	int hi;
75 
76 	volume = get_volume(HAMMER_VOL_DECODE(zone2_offset));
77 	assert(volume);
78 
79 	hi = buffer_hash(zone2_offset);
80 	TAILQ_FOREACH(buffer, &volume->buffer_lists[hi], entry) {
81 		if (buffer->zone2_offset == zone2_offset)
82 			return(buffer);
83 	}
84 	return(NULL);
85 }
86 
87 static
88 volume_info_t
89 __alloc_volume(const char *volname, int oflags)
90 {
91 	volume_info_t volume;
92 	int i;
93 
94 	volume = calloc(1, sizeof(*volume));
95 	volume->vol_no = -1;
96 	volume->rdonly = (oflags == O_RDONLY);
97 	volume->name = strdup(volname);
98 	volume->fd = open(volume->name, oflags);
99 	if (volume->fd < 0) {
100 		err(1, "alloc_volume: Failed to open %s", volume->name);
101 		/* not reached */
102 	}
103 	check_volume(volume);
104 
105 	volume->ondisk = calloc(1, HAMMER_BUFSIZE);
106 
107 	for (i = 0; i < HAMMER_BUFLISTS; ++i)
108 		TAILQ_INIT(&volume->buffer_lists[i]);
109 
110 	return(volume);
111 }
112 
113 static
114 void
115 __add_volume(const volume_info_t volume)
116 {
117 	volume_info_t scan;
118 	struct stat st1, st2;
119 
120 	if (fstat(volume->fd, &st1) != 0) {
121 		errx(1, "add_volume: %s: Failed to stat", volume->name);
122 		/* not reached */
123 	}
124 
125 	TAILQ_FOREACH(scan, &VolList, entry) {
126 		if (scan->vol_no == volume->vol_no) {
127 			errx(1, "add_volume: %s: Duplicate volume number %d "
128 				"against %s",
129 				volume->name, volume->vol_no, scan->name);
130 			/* not reached */
131 		}
132 		if (fstat(scan->fd, &st2) != 0) {
133 			errx(1, "add_volume: %s: Failed to stat %s",
134 				volume->name, scan->name);
135 			/* not reached */
136 		}
137 		if ((st1.st_ino == st2.st_ino) && (st1.st_dev == st2.st_dev)) {
138 			errx(1, "add_volume: %s: Specified more than once",
139 				volume->name);
140 			/* not reached */
141 		}
142 	}
143 
144 	TAILQ_INSERT_TAIL(&VolList, volume, entry);
145 }
146 
147 static
148 void
149 __verify_volume(const volume_info_t volume)
150 {
151 	hammer_volume_ondisk_t ondisk = volume->ondisk;
152 	char *fstype;
153 
154 	if (ondisk->vol_signature != HAMMER_FSBUF_VOLUME) {
155 		errx(1, "verify_volume: Invalid volume signature %016jx",
156 			ondisk->vol_signature);
157 		/* not reached */
158 	}
159 	if (ondisk->vol_rootvol != HAMMER_ROOT_VOLNO) {
160 		errx(1, "verify_volume: Invalid root volume# %d",
161 			ondisk->vol_rootvol);
162 		/* not reached */
163 	}
164 	hammer_uuid_to_string(&ondisk->vol_fstype, &fstype);
165 	if (hammer_uuid_compare(&Hammer_FSType, &ondisk->vol_fstype)) {
166 		errx(1, "verify_volume: %s: fstype %s does not indicate "
167 			"this is a HAMMER volume", volume->name, fstype);
168 		/* not reached */
169 	}
170 	free(fstype);
171 	if (hammer_uuid_compare(&Hammer_FSId, &ondisk->vol_fsid)) {
172 		errx(1, "verify_volume: %s: fsid does not match other volumes!",
173 			volume->name);
174 		/* not reached */
175 	}
176 	if (ondisk->vol_version < HAMMER_VOL_VERSION_MIN ||
177 	    ondisk->vol_version >= HAMMER_VOL_VERSION_WIP) {
178 		errx(1, "verify_volume: %s: Invalid volume version %u",
179 			volume->name, ondisk->vol_version);
180 		/* not reached */
181 	}
182 }
183 
184 /*
185  * Initialize a volume structure and ondisk vol_no field.
186  */
187 volume_info_t
188 init_volume(const char *filename, int oflags, int32_t vol_no)
189 {
190 	volume_info_t volume;
191 
192 	volume = __alloc_volume(filename, oflags);
193 	volume->vol_no = volume->ondisk->vol_no = vol_no;
194 
195 	__add_volume(volume);
196 
197 	return(volume);
198 }
199 
200 /*
201  * Initialize a volume structure and read ondisk volume header.
202  */
203 volume_info_t
204 load_volume(const char *filename, int oflags, int verify_volume)
205 {
206 	volume_info_t volume;
207 	int n;
208 
209 	volume = __alloc_volume(filename, oflags);
210 
211 	n = readhammervol(volume);
212 	if (n == -1) {
213 		err(1, "load_volume: %s: Read failed at offset 0",
214 		    volume->name);
215 		/* not reached */
216 	}
217 	volume->vol_no = volume->ondisk->vol_no;
218 	if (volume->vol_no == HAMMER_ROOT_VOLNO)
219 		HammerVersion = volume->ondisk->vol_version;
220 
221 	if (valid_hammer_volumes++ == 0)
222 		Hammer_FSId = volume->ondisk->vol_fsid;
223 	if (verify_volume)
224 		__verify_volume(volume);
225 
226 	__add_volume(volume);
227 
228 	return(volume);
229 }
230 
231 /*
232  * Check basic volume characteristics.
233  */
234 static
235 void
236 check_volume(volume_info_t volume)
237 {
238 	struct partinfo pinfo;
239 	struct stat st;
240 
241 	/*
242 	 * Allow the formatting of block devices or regular files
243 	 */
244 	if (ioctl(volume->fd, DIOCGPART, &pinfo) < 0) {
245 		if (fstat(volume->fd, &st) < 0) {
246 			err(1, "Unable to stat %s", volume->name);
247 			/* not reached */
248 		}
249 		if (S_ISREG(st.st_mode)) {
250 			volume->size = st.st_size;
251 			volume->type = "REGFILE";
252 		} else {
253 			errx(1, "Unsupported file type for %s", volume->name);
254 			/* not reached */
255 		}
256 	} else {
257 		/*
258 		 * When formatting a block device as a HAMMER volume the
259 		 * sector size must be compatible.  HAMMER uses 16384 byte
260 		 * filesystem buffers.
261 		 */
262 		if (pinfo.reserved_blocks) {
263 			errx(1, "HAMMER cannot be placed in a partition "
264 				"which overlaps the disklabel or MBR");
265 			/* not reached */
266 		}
267 		if (pinfo.media_blksize > HAMMER_BUFSIZE ||
268 		    HAMMER_BUFSIZE % pinfo.media_blksize) {
269 			errx(1, "A media sector size of %d is not supported",
270 			     pinfo.media_blksize);
271 			/* not reached */
272 		}
273 
274 		volume->size = pinfo.media_size;
275 		volume->device_offset = pinfo.media_offset;
276 		volume->type = "DEVICE";
277 	}
278 }
279 
280 int
281 is_regfile(const volume_info_t volume)
282 {
283 	return(strcmp(volume->type, "REGFILE") ? 0 : 1);
284 }
285 
286 void
287 assert_volume_offset(const volume_info_t volume)
288 {
289 	assert(hammer_is_zone_raw_buffer(volume->vol_free_off));
290 	assert(hammer_is_zone_raw_buffer(volume->vol_free_end));
291 	if (volume->vol_free_off >= volume->vol_free_end) {
292 		errx(1, "Ran out of room, filesystem too small");
293 		/* not reached */
294 	}
295 }
296 
297 volume_info_t
298 get_volume(int32_t vol_no)
299 {
300 	volume_info_t volume;
301 
302 	TAILQ_FOREACH(volume, &VolList, entry) {
303 		if (volume->vol_no == vol_no)
304 			break;
305 	}
306 
307 	return(volume);
308 }
309 
310 volume_info_t
311 get_root_volume(void)
312 {
313 	return(get_volume(HAMMER_ROOT_VOLNO));
314 }
315 
316 static
317 hammer_off_t
318 __blockmap_xlate_to_zone2(hammer_off_t buf_offset)
319 {
320 	hammer_off_t zone2_offset;
321 	int error = 0;
322 
323 	if (hammer_is_zone_raw_buffer(buf_offset))
324 		zone2_offset = buf_offset;
325 	else
326 		zone2_offset = blockmap_lookup(buf_offset, &error);
327 
328 	if (error)
329 		return(HAMMER_OFF_BAD);
330 	assert(hammer_is_zone_raw_buffer(zone2_offset));
331 
332 	return(zone2_offset);
333 }
334 
335 static
336 buffer_info_t
337 __alloc_buffer(hammer_off_t zone2_offset, int isnew)
338 {
339 	volume_info_t volume;
340 	buffer_info_t buffer;
341 	int hi;
342 
343 	volume = get_volume(HAMMER_VOL_DECODE(zone2_offset));
344 	assert(volume != NULL);
345 
346 	buffer = calloc(1, sizeof(*buffer));
347 	buffer->zone2_offset = zone2_offset;
348 	buffer->raw_offset = hammer_xlate_to_phys(volume->ondisk, zone2_offset);
349 	buffer->volume = volume;
350 	buffer->ondisk = calloc(1, HAMMER_BUFSIZE);
351 
352 	if (isnew <= 0) {
353 		if (readhammerbuf(buffer) == -1) {
354 			err(1, "Failed to read %s:%016jx at %016jx",
355 			    volume->name,
356 			    (intmax_t)buffer->zone2_offset,
357 			    (intmax_t)buffer->raw_offset);
358 			/* not reached */
359 		}
360 	}
361 
362 	hi = buffer_hash(zone2_offset);
363 	TAILQ_INSERT_TAIL(&volume->buffer_lists[hi], buffer, entry);
364 	hammer_cache_add(&buffer->cache);
365 
366 	return(buffer);
367 }
368 
369 /*
370  * Acquire the 16KB buffer for specified zone offset.
371  */
372 static
373 buffer_info_t
374 get_buffer(hammer_off_t buf_offset, int isnew)
375 {
376 	buffer_info_t buffer;
377 	hammer_off_t zone2_offset;
378 	int dora = 0;
379 
380 	zone2_offset = __blockmap_xlate_to_zone2(buf_offset);
381 	if (zone2_offset == HAMMER_OFF_BAD)
382 		return(NULL);
383 
384 	zone2_offset &= ~HAMMER_BUFMASK64;
385 	buffer = find_buffer(zone2_offset);
386 
387 	if (buffer == NULL) {
388 		buffer = __alloc_buffer(zone2_offset, isnew);
389 		dora = (isnew == 0);
390 	} else {
391 		assert(isnew != -1);
392 		hammer_cache_used(&buffer->cache);
393 	}
394 	assert(buffer->ondisk != NULL);
395 
396 	++buffer->cache.refs;
397 	hammer_cache_flush();
398 
399 	if (isnew > 0) {
400 		assert(buffer->cache.modified == 0);
401 		bzero(buffer->ondisk, HAMMER_BUFSIZE);
402 		buffer->cache.modified = 1;
403 	}
404 	if (dora)
405 		get_buffer_readahead(buffer);
406 	return(buffer);
407 }
408 
409 static
410 void
411 get_buffer_readahead(const buffer_info_t base)
412 {
413 	buffer_info_t buffer;
414 	volume_info_t volume;
415 	hammer_off_t zone2_offset;
416 	int64_t raw_offset;
417 	int ri = UseReadBehind;
418 	int re = UseReadAhead;
419 
420 	raw_offset = base->raw_offset + ri * HAMMER_BUFSIZE;
421 	volume = base->volume;
422 
423 	while (ri < re) {
424 		if (raw_offset >= volume->ondisk->vol_buf_end)
425 			break;
426 		if (raw_offset < volume->ondisk->vol_buf_beg || ri == 0) {
427 			++ri;
428 			raw_offset += HAMMER_BUFSIZE;
429 			continue;
430 		}
431 		zone2_offset = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no,
432 			raw_offset - volume->ondisk->vol_buf_beg);
433 		buffer = find_buffer(zone2_offset);
434 		if (buffer == NULL) {
435 			/* call with -1 to prevent another readahead */
436 			buffer = get_buffer(zone2_offset, -1);
437 			rel_buffer(buffer);
438 		}
439 		++ri;
440 		raw_offset += HAMMER_BUFSIZE;
441 	}
442 }
443 
444 void
445 rel_buffer(buffer_info_t buffer)
446 {
447 	volume_info_t volume;
448 	int hi;
449 
450 	if (buffer == NULL)
451 		return;
452 	assert(buffer->cache.refs > 0);
453 	if (--buffer->cache.refs == 0) {
454 		if (buffer->cache.delete) {
455 			hi = buffer_hash(buffer->zone2_offset);
456 			volume = buffer->volume;
457 			if (buffer->cache.modified)
458 				flush_buffer(buffer);
459 			TAILQ_REMOVE(&volume->buffer_lists[hi], buffer, entry);
460 			hammer_cache_del(&buffer->cache);
461 			free(buffer->ondisk);
462 			free(buffer);
463 		}
464 	}
465 }
466 
467 /*
468  * Retrieve a pointer to a buffer data given a zone-X buffer offset.
469  * The underlying bufferp is freed if isnew or the corresponding zone-2
470  * offset is out of range of the cached data.  If bufferp is freed,
471  * a referenced buffer is loaded into it.
472  */
473 void *
474 get_buffer_data(hammer_off_t buf_offset, buffer_info_t *bufferp, int isnew)
475 {
476 	hammer_off_t xor = 0;
477 	hammer_volume_ondisk_t ondisk;
478 
479 	if (*bufferp != NULL) {
480 		if (hammer_is_zone_undo(buf_offset)) {
481 			ondisk = (*bufferp)->volume->ondisk;
482 			xor = hammer_xlate_to_undo(ondisk, buf_offset) ^
483 				(*bufferp)->zone2_offset;
484 		} else if (hammer_is_zone_direct_xlated(buf_offset)) {
485 			xor = HAMMER_OFF_LONG_ENCODE(buf_offset) ^
486 			      HAMMER_OFF_LONG_ENCODE((*bufferp)->zone2_offset);
487 		} else {
488 			assert(0);
489 		}
490 		if (isnew > 0 || (xor & ~HAMMER_BUFMASK64)) {
491 			rel_buffer(*bufferp);
492 			*bufferp = NULL;
493 		} else {
494 			hammer_cache_used(&(*bufferp)->cache);
495 		}
496 	}
497 
498 	if (*bufferp == NULL) {
499 		*bufferp = get_buffer(buf_offset, isnew);
500 		if (*bufferp == NULL)
501 			return(NULL);
502 	}
503 
504 	return((char *)(*bufferp)->ondisk +
505 		((int32_t)buf_offset & HAMMER_BUFMASK));
506 }
507 
508 /*
509  * Allocate HAMMER elements - B-Tree nodes
510  */
511 hammer_node_ondisk_t
512 alloc_btree_node(hammer_off_t *offp, buffer_info_t *data_bufferp)
513 {
514 	hammer_node_ondisk_t node;
515 
516 	node = alloc_blockmap(HAMMER_ZONE_BTREE_INDEX, sizeof(*node),
517 			      offp, data_bufferp);
518 	bzero(node, sizeof(*node));
519 	return(node);
520 }
521 
522 /*
523  * Allocate HAMMER elements - meta data (inode, direntry, PFS, etc)
524  */
525 void *
526 alloc_meta_element(hammer_off_t *offp, int32_t data_len,
527 		   buffer_info_t *data_bufferp)
528 {
529 	void *data;
530 
531 	data = alloc_blockmap(HAMMER_ZONE_META_INDEX, data_len,
532 			      offp, data_bufferp);
533 	bzero(data, data_len);
534 	return(data);
535 }
536 
537 /*
538  * Format a new blockmap.  This is mostly a degenerate case because
539  * all allocations are now actually done from the freemap.
540  */
541 void
542 format_blockmap(volume_info_t root_vol, int zone, hammer_off_t offset)
543 {
544 	hammer_blockmap_t blockmap;
545 	hammer_off_t zone_base;
546 
547 	/* Only root volume needs formatting */
548 	assert(root_vol->vol_no == HAMMER_ROOT_VOLNO);
549 
550 	assert(hammer_is_index_record(zone));
551 
552 	blockmap = &root_vol->ondisk->vol0_blockmap[zone];
553 	zone_base = HAMMER_ZONE_ENCODE(zone, offset);
554 
555 	bzero(blockmap, sizeof(*blockmap));
556 	blockmap->phys_offset = 0;
557 	blockmap->first_offset = zone_base;
558 	blockmap->next_offset = zone_base;
559 	blockmap->alloc_offset = HAMMER_ENCODE(zone, 255, -1);
560 	hammer_crc_set_blockmap(HammerVersion, blockmap);
561 }
562 
563 /*
564  * Format a new freemap.  Set all layer1 entries to UNAVAIL.  The initialize
565  * code will load each volume's freemap.
566  */
567 void
568 format_freemap(volume_info_t root_vol)
569 {
570 	buffer_info_t buffer = NULL;
571 	hammer_off_t layer1_offset;
572 	hammer_blockmap_t blockmap;
573 	hammer_blockmap_layer1_t layer1;
574 	int i, isnew;
575 
576 	/* Only root volume needs formatting */
577 	assert(root_vol->vol_no == HAMMER_ROOT_VOLNO);
578 
579 	layer1_offset = bootstrap_bigblock(root_vol);
580 	for (i = 0; i < HAMMER_BIGBLOCK_SIZE; i += sizeof(*layer1)) {
581 		isnew = ((i % HAMMER_BUFSIZE) == 0);
582 		layer1 = get_buffer_data(layer1_offset + i, &buffer, isnew);
583 		bzero(layer1, sizeof(*layer1));
584 		layer1->phys_offset = HAMMER_BLOCKMAP_UNAVAIL;
585 		layer1->blocks_free = 0;
586 		hammer_crc_set_layer1(HammerVersion, layer1);
587 	}
588 	assert(i == HAMMER_BIGBLOCK_SIZE);
589 	rel_buffer(buffer);
590 
591 	blockmap = &root_vol->ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
592 	bzero(blockmap, sizeof(*blockmap));
593 	blockmap->phys_offset = layer1_offset;
594 	blockmap->first_offset = 0;
595 	blockmap->next_offset = HAMMER_ENCODE_RAW_BUFFER(0, 0);
596 	blockmap->alloc_offset = HAMMER_ENCODE_RAW_BUFFER(255, -1);
597 	hammer_crc_set_blockmap(HammerVersion, blockmap);
598 }
599 
600 /*
601  * Load the volume's remaining free space into the freemap.
602  *
603  * Returns the number of big-blocks available.
604  */
605 int64_t
606 initialize_freemap(volume_info_t volume)
607 {
608 	volume_info_t root_vol;
609 	buffer_info_t buffer1 = NULL;
610 	buffer_info_t buffer2 = NULL;
611 	hammer_blockmap_layer1_t layer1;
612 	hammer_blockmap_layer2_t layer2;
613 	hammer_off_t layer1_offset;
614 	hammer_off_t layer2_offset;
615 	hammer_off_t phys_offset;
616 	hammer_off_t block_offset;
617 	hammer_off_t aligned_vol_free_end;
618 	hammer_blockmap_t freemap;
619 	int64_t count = 0;
620 	int64_t layer1_count = 0;
621 
622 	root_vol = get_root_volume();
623 
624 	assert_volume_offset(volume);
625 	aligned_vol_free_end = HAMMER_BLOCKMAP_LAYER2_DOALIGN(volume->vol_free_end);
626 
627 	printf("initialize freemap volume %d\n", volume->vol_no);
628 
629 	/*
630 	 * Initialize the freemap.  First preallocate the big-blocks required
631 	 * to implement layer2.   This preallocation is a bootstrap allocation
632 	 * using blocks from the target volume.
633 	 */
634 	freemap = &root_vol->ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
635 
636 	for (phys_offset = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no, 0);
637 	     phys_offset < aligned_vol_free_end;
638 	     phys_offset += HAMMER_BLOCKMAP_LAYER2) {
639 		layer1_offset = freemap->phys_offset +
640 				HAMMER_BLOCKMAP_LAYER1_OFFSET(phys_offset);
641 		layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
642 		if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL) {
643 			layer1->phys_offset = bootstrap_bigblock(volume);
644 			layer1->blocks_free = 0;
645 			buffer1->cache.modified = 1;
646 			hammer_crc_set_layer1(HammerVersion, layer1);
647 		}
648 	}
649 
650 	/*
651 	 * Now fill everything in.
652 	 */
653 	for (phys_offset = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no, 0);
654 	     phys_offset < aligned_vol_free_end;
655 	     phys_offset += HAMMER_BLOCKMAP_LAYER2) {
656 		layer1_count = 0;
657 		layer1_offset = freemap->phys_offset +
658 				HAMMER_BLOCKMAP_LAYER1_OFFSET(phys_offset);
659 		layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
660 		assert(layer1->phys_offset != HAMMER_BLOCKMAP_UNAVAIL);
661 
662 		for (block_offset = 0;
663 		     block_offset < HAMMER_BLOCKMAP_LAYER2;
664 		     block_offset += HAMMER_BIGBLOCK_SIZE) {
665 			layer2_offset = layer1->phys_offset +
666 				        HAMMER_BLOCKMAP_LAYER2_OFFSET(block_offset);
667 			layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
668 			bzero(layer2, sizeof(*layer2));
669 
670 			if (phys_offset + block_offset < volume->vol_free_off) {
671 				/*
672 				 * Big-blocks already allocated as part
673 				 * of the freemap bootstrap.
674 				 */
675 				layer2->zone = HAMMER_ZONE_FREEMAP_INDEX;
676 				layer2->append_off = HAMMER_BIGBLOCK_SIZE;
677 				layer2->bytes_free = 0;
678 			} else if (phys_offset + block_offset < volume->vol_free_end) {
679 				layer2->zone = 0;
680 				layer2->append_off = 0;
681 				layer2->bytes_free = HAMMER_BIGBLOCK_SIZE;
682 				++count;
683 				++layer1_count;
684 			} else {
685 				layer2->zone = HAMMER_ZONE_UNAVAIL_INDEX;
686 				layer2->append_off = HAMMER_BIGBLOCK_SIZE;
687 				layer2->bytes_free = 0;
688 			}
689 			hammer_crc_set_layer2(HammerVersion, layer2);
690 			buffer2->cache.modified = 1;
691 		}
692 
693 		layer1->blocks_free += layer1_count;
694 		hammer_crc_set_layer1(HammerVersion, layer1);
695 		buffer1->cache.modified = 1;
696 	}
697 
698 	rel_buffer(buffer1);
699 	rel_buffer(buffer2);
700 	return(count);
701 }
702 
703 /*
704  * Returns the number of big-blocks available for filesystem data and undos
705  * without formatting.
706  */
707 int64_t
708 count_freemap(const volume_info_t volume)
709 {
710 	hammer_off_t phys_offset;
711 	hammer_off_t vol_free_off;
712 	hammer_off_t aligned_vol_free_end;
713 	int64_t count = 0;
714 
715 	vol_free_off = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no, 0);
716 
717 	assert_volume_offset(volume);
718 	aligned_vol_free_end = HAMMER_BLOCKMAP_LAYER2_DOALIGN(volume->vol_free_end);
719 
720 	if (volume->vol_no == HAMMER_ROOT_VOLNO)
721 		vol_free_off += HAMMER_BIGBLOCK_SIZE;
722 
723 	for (phys_offset = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no, 0);
724 	     phys_offset < aligned_vol_free_end;
725 	     phys_offset += HAMMER_BLOCKMAP_LAYER2) {
726 		vol_free_off += HAMMER_BIGBLOCK_SIZE;
727 	}
728 
729 	for (phys_offset = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no, 0);
730 	     phys_offset < aligned_vol_free_end;
731 	     phys_offset += HAMMER_BIGBLOCK_SIZE) {
732 		if (phys_offset < vol_free_off)
733 			;
734 		else if (phys_offset < volume->vol_free_end)
735 			++count;
736 	}
737 
738 	return(count);
739 }
740 
741 /*
742  * Format the undomap for the root volume.
743  */
744 void
745 format_undomap(volume_info_t root_vol, int64_t *undo_buffer_size)
746 {
747 	hammer_off_t undo_limit;
748 	hammer_blockmap_t blockmap;
749 	hammer_volume_ondisk_t ondisk;
750 	buffer_info_t buffer = NULL;
751 	hammer_off_t scan;
752 	int n;
753 	int limit_index;
754 	uint32_t seqno;
755 
756 	/* Only root volume needs formatting */
757 	assert(root_vol->vol_no == HAMMER_ROOT_VOLNO);
758 	ondisk = root_vol->ondisk;
759 
760 	/*
761 	 * Size the undo buffer in multiples of HAMMER_BIGBLOCK_SIZE,
762 	 * up to HAMMER_MAX_UNDO_BIGBLOCKS big-blocks.
763 	 * Size to approximately 0.1% of the disk.
764 	 *
765 	 * The minimum UNDO fifo size is 512MB, or approximately 1% of
766 	 * the recommended 50G disk.
767 	 *
768 	 * Changing this minimum is rather dangerous as complex filesystem
769 	 * operations can cause the UNDO FIFO to fill up otherwise.
770 	 */
771 	undo_limit = *undo_buffer_size;
772 	if (undo_limit == 0) {
773 		undo_limit = HAMMER_VOL_BUF_SIZE(ondisk) / 1000;
774 		if (undo_limit < HAMMER_BIGBLOCK_SIZE * HAMMER_MIN_UNDO_BIGBLOCKS)
775 			undo_limit = HAMMER_BIGBLOCK_SIZE * HAMMER_MIN_UNDO_BIGBLOCKS;
776 	}
777 	undo_limit = HAMMER_BIGBLOCK_DOALIGN(undo_limit);
778 	if (undo_limit < HAMMER_BIGBLOCK_SIZE)
779 		undo_limit = HAMMER_BIGBLOCK_SIZE;
780 	if (undo_limit > HAMMER_BIGBLOCK_SIZE * HAMMER_MAX_UNDO_BIGBLOCKS)
781 		undo_limit = HAMMER_BIGBLOCK_SIZE * HAMMER_MAX_UNDO_BIGBLOCKS;
782 	*undo_buffer_size = undo_limit;
783 
784 	blockmap = &ondisk->vol0_blockmap[HAMMER_ZONE_UNDO_INDEX];
785 	bzero(blockmap, sizeof(*blockmap));
786 	blockmap->phys_offset = HAMMER_BLOCKMAP_UNAVAIL;
787 	blockmap->first_offset = HAMMER_ENCODE_UNDO(0);
788 	blockmap->next_offset = blockmap->first_offset;
789 	blockmap->alloc_offset = HAMMER_ENCODE_UNDO(undo_limit);
790 	hammer_crc_set_blockmap(HammerVersion, blockmap);
791 
792 	limit_index = undo_limit / HAMMER_BIGBLOCK_SIZE;
793 	assert(limit_index <= HAMMER_MAX_UNDO_BIGBLOCKS);
794 
795 	for (n = 0; n < limit_index; ++n)
796 		ondisk->vol0_undo_array[n] = alloc_undo_bigblock(root_vol);
797 	while (n < HAMMER_MAX_UNDO_BIGBLOCKS)
798 		ondisk->vol0_undo_array[n++] = HAMMER_BLOCKMAP_UNAVAIL;
799 
800 	/*
801 	 * Pre-initialize the UNDO blocks (HAMMER version 4+)
802 	 */
803 	printf("initializing the undo map (%jd MB)\n",
804 		(intmax_t)HAMMER_OFF_LONG_ENCODE(blockmap->alloc_offset) /
805 		(1024 * 1024));
806 
807 	scan = blockmap->first_offset;
808 	seqno = 0;
809 
810 	while (scan < blockmap->alloc_offset) {
811 		hammer_fifo_head_t head;
812 		hammer_fifo_tail_t tail;
813 		int bytes = HAMMER_UNDO_ALIGN;
814 		int isnew = ((scan & HAMMER_BUFMASK64) == 0);
815 
816 		head = get_buffer_data(scan, &buffer, isnew);
817 		buffer->cache.modified = 1;
818 		tail = (void *)((char *)head + bytes - sizeof(*tail));
819 
820 		bzero(head, bytes);
821 		head->hdr_signature = HAMMER_HEAD_SIGNATURE;
822 		head->hdr_type = HAMMER_HEAD_TYPE_DUMMY;
823 		head->hdr_size = bytes;
824 		head->hdr_seq = seqno++;
825 
826 		tail->tail_signature = HAMMER_TAIL_SIGNATURE;
827 		tail->tail_type = HAMMER_HEAD_TYPE_DUMMY;
828 		tail->tail_size = bytes;
829 
830 		hammer_crc_set_fifo_head(HammerVersion, head, bytes);
831 
832 		scan += bytes;
833 	}
834 	rel_buffer(buffer);
835 }
836 
837 const char *zone_labels[] = {
838 	"",		/* 0 */
839 	"raw_volume",	/* 1 */
840 	"raw_buffer",	/* 2 */
841 	"undo",		/* 3 */
842 	"freemap",	/* 4 */
843 	"",		/* 5 */
844 	"",		/* 6 */
845 	"",		/* 7 */
846 	"btree",	/* 8 */
847 	"meta",		/* 9 */
848 	"large_data",	/* 10 */
849 	"small_data",	/* 11 */
850 	"",		/* 12 */
851 	"",		/* 13 */
852 	"",		/* 14 */
853 	"unavail",	/* 15 */
854 };
855 
856 void
857 print_blockmap(const volume_info_t volume)
858 {
859 	hammer_blockmap_t blockmap;
860 	hammer_volume_ondisk_t ondisk = volume->ondisk;
861 	int64_t size, used;
862 	int i;
863 	char *fstype, *fsid;
864 #define INDENT ""
865 
866 	printf(INDENT"vol_label\t%s\n", ondisk->vol_label);
867 	printf(INDENT"vol_count\t%d\n", ondisk->vol_count);
868 
869 	hammer_uuid_to_string(&ondisk->vol_fstype, &fstype);
870 	hammer_uuid_to_string(&ondisk->vol_fsid, &fsid);
871 	printf(INDENT"vol_fstype\t%s", fstype);
872 	if (strcmp(fstype, "61dc63ac-6e38-11dc-8513-01301bb8a9f5") == 0)
873 		printf(" \"%s\"\n", HAMMER_FSTYPE_STRING);
874 	else
875 		printf("\n"); /* invalid UUID */
876 	printf(INDENT"vol_fsid\t%s\n", fsid);
877 	free(fstype);
878 	free(fsid);
879 
880 	printf(INDENT"vol_bot_beg\t%s\n", sizetostr(ondisk->vol_bot_beg));
881 	printf(INDENT"vol_mem_beg\t%s\n", sizetostr(ondisk->vol_mem_beg));
882 	printf(INDENT"vol_buf_beg\t%s\n", sizetostr(ondisk->vol_buf_beg));
883 	printf(INDENT"vol_buf_end\t%s\n", sizetostr(ondisk->vol_buf_end));
884 	printf(INDENT"vol0_next_tid\t%016jx\n",
885 	       (uintmax_t)ondisk->vol0_next_tid);
886 
887 	blockmap = &ondisk->vol0_blockmap[HAMMER_ZONE_UNDO_INDEX];
888 	size = HAMMER_OFF_LONG_ENCODE(blockmap->alloc_offset);
889 	if (blockmap->first_offset <= blockmap->next_offset)
890 		used = blockmap->next_offset - blockmap->first_offset;
891 	else
892 		used = blockmap->alloc_offset - blockmap->first_offset +
893 			HAMMER_OFF_LONG_ENCODE(blockmap->next_offset);
894 	printf(INDENT"undo_size\t%s\n", sizetostr(size));
895 	printf(INDENT"undo_used\t%s\n", sizetostr(used));
896 
897 	printf(INDENT"zone #             "
898 	       "phys             first            next             alloc\n");
899 	for (i = 0; i < HAMMER_MAX_ZONES; i++) {
900 		blockmap = &ondisk->vol0_blockmap[i];
901 		printf(INDENT"zone %-2d %-10s %016jx %016jx %016jx %016jx\n",
902 			i, zone_labels[i],
903 			(uintmax_t)blockmap->phys_offset,
904 			(uintmax_t)blockmap->first_offset,
905 			(uintmax_t)blockmap->next_offset,
906 			(uintmax_t)blockmap->alloc_offset);
907 	}
908 }
909 
910 /*
911  * Flush various tracking structures to disk
912  */
913 void
914 flush_all_volumes(void)
915 {
916 	volume_info_t volume;
917 
918 	TAILQ_FOREACH(volume, &VolList, entry)
919 		flush_volume(volume);
920 }
921 
922 void
923 flush_volume(volume_info_t volume)
924 {
925 	buffer_info_t buffer;
926 	int i;
927 
928 	for (i = 0; i < HAMMER_BUFLISTS; ++i) {
929 		TAILQ_FOREACH(buffer, &volume->buffer_lists[i], entry)
930 			flush_buffer(buffer);
931 	}
932 	if (writehammervol(volume) == -1) {
933 		err(1, "Write volume %d (%s)", volume->vol_no, volume->name);
934 		/* not reached */
935 	}
936 }
937 
938 void
939 flush_buffer(buffer_info_t buffer)
940 {
941 	volume_info_t volume;
942 
943 	volume = buffer->volume;
944 	if (writehammerbuf(buffer) == -1) {
945 		err(1, "Write volume %d (%s)", volume->vol_no, volume->name);
946 		/* not reached */
947 	}
948 	buffer->cache.modified = 0;
949 }
950 
951 /*
952  * Core I/O operations
953  */
954 static
955 int
956 __read(volume_info_t volume, void *data, int64_t offset, int size)
957 {
958 	ssize_t n;
959 
960 	n = pread(volume->fd, data, size, offset);
961 	if (n != size)
962 		return(-1);
963 	return(0);
964 }
965 
966 static __inline
967 int
968 readhammervol(volume_info_t volume)
969 {
970 	return(__read(volume, volume->ondisk, 0, HAMMER_BUFSIZE));
971 }
972 
973 static __inline
974 int
975 readhammerbuf(buffer_info_t buffer)
976 {
977 	return(__read(buffer->volume, buffer->ondisk, buffer->raw_offset,
978 		HAMMER_BUFSIZE));
979 }
980 
981 static
982 int
983 __write(volume_info_t volume, const void *data, int64_t offset, int size)
984 {
985 	ssize_t n;
986 
987 	if (volume->rdonly)
988 		return(0);
989 
990 	n = pwrite(volume->fd, data, size, offset);
991 	if (n != size)
992 		return(-1);
993 	return(0);
994 }
995 
996 static __inline
997 int
998 writehammervol(volume_info_t volume)
999 {
1000 	return(__write(volume, volume->ondisk, 0, HAMMER_BUFSIZE));
1001 }
1002 
1003 static __inline
1004 int
1005 writehammerbuf(buffer_info_t buffer)
1006 {
1007 	return(__write(buffer->volume, buffer->ondisk, buffer->raw_offset,
1008 		HAMMER_BUFSIZE));
1009 }
1010 
1011 int64_t
1012 init_boot_area_size(int64_t value, off_t avg_vol_size)
1013 {
1014 	if (value == 0) {
1015 		value = HAMMER_BOOT_NOMBYTES;
1016 		while (value > avg_vol_size / HAMMER_MAX_VOLUMES)
1017 			value >>= 1;
1018 	}
1019 
1020 	if (value < HAMMER_BOOT_MINBYTES)
1021 		value = HAMMER_BOOT_MINBYTES;
1022 	else if (value > HAMMER_BOOT_MAXBYTES)
1023 		value = HAMMER_BOOT_MAXBYTES;
1024 
1025 	return(value);
1026 }
1027 
1028 int64_t
1029 init_memory_log_size(int64_t value, off_t avg_vol_size)
1030 {
1031 	if (value == 0) {
1032 		value = HAMMER_MEM_NOMBYTES;
1033 		while (value > avg_vol_size / HAMMER_MAX_VOLUMES)
1034 			value >>= 1;
1035 	}
1036 
1037 	if (value < HAMMER_MEM_MINBYTES)
1038 		value = HAMMER_MEM_MINBYTES;
1039 	else if (value > HAMMER_MEM_MAXBYTES)
1040 		value = HAMMER_MEM_MAXBYTES;
1041 
1042 	return(value);
1043 }
1044