xref: /dragonfly/sys/vfs/hammer/hammer_reblock.c (revision 8a7bdfea)
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/sys/vfs/hammer/hammer_reblock.c,v 1.8 2008/04/27 00:45:37 dillon Exp $
35  */
36 /*
37  * HAMMER reblocker - This code frees up fragmented physical space
38  *
39  * HAMMER only keeps track of free space on a big-block basis.  A big-block
40  * containing holes can only be freed by migrating the remaining data in
41  * that big-block into a new big-block, then freeing the big-block.
42  *
43  * This function is called from an ioctl or via the hammer support thread.
44  */
45 
46 #include "hammer.h"
47 
48 static int hammer_reblock_helper(struct hammer_ioc_reblock *reblock,
49 				 hammer_cursor_t cursor,
50 				 hammer_btree_elm_t elm);
51 static int hammer_reblock_data(struct hammer_ioc_reblock *reblock,
52 				hammer_cursor_t cursor, hammer_btree_elm_t elm);
53 static int hammer_reblock_record(struct hammer_ioc_reblock *reblock,
54 				hammer_cursor_t cursor, hammer_btree_elm_t elm);
55 static int hammer_reblock_node(struct hammer_ioc_reblock *reblock,
56 				hammer_cursor_t cursor, hammer_btree_elm_t elm);
57 
58 int
59 hammer_ioc_reblock(hammer_transaction_t trans, hammer_inode_t ip,
60 	       struct hammer_ioc_reblock *reblock)
61 {
62 	struct hammer_cursor cursor;
63 	hammer_btree_elm_t elm;
64 	int error;
65 
66 	if (reblock->beg_obj_id >= reblock->end_obj_id)
67 		return(EINVAL);
68 	if (reblock->free_level < 0)
69 		return(EINVAL);
70 
71 retry:
72 	error = hammer_init_cursor(trans, &cursor, NULL);
73 	if (error) {
74 		hammer_done_cursor(&cursor);
75 		return(error);
76 	}
77 	cursor.key_beg.obj_id = reblock->cur_obj_id;
78 	cursor.key_beg.key = HAMMER_MIN_KEY;
79 	cursor.key_beg.create_tid = 1;
80 	cursor.key_beg.delete_tid = 0;
81 	cursor.key_beg.rec_type = HAMMER_MIN_RECTYPE;
82 	cursor.key_beg.obj_type = 0;
83 
84 	cursor.key_end.obj_id = reblock->end_obj_id;
85 	cursor.key_end.key = HAMMER_MAX_KEY;
86 	cursor.key_end.create_tid = HAMMER_MAX_TID - 1;
87 	cursor.key_end.delete_tid = 0;
88 	cursor.key_end.rec_type = HAMMER_MAX_RECTYPE;
89 	cursor.key_end.obj_type = 0;
90 
91 	cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE;
92 	cursor.flags |= HAMMER_CURSOR_BACKEND;
93 
94 	error = hammer_btree_first(&cursor);
95 	while (error == 0) {
96 		elm = &cursor.node->ondisk->elms[cursor.index];
97 		reblock->cur_obj_id = elm->base.obj_id;
98 
99 		/*
100 		 * Acquiring the sync_lock prevents the operation from
101 		 * crossing a synchronization boundary.
102 		 */
103 		hammer_lock_ex(&trans->hmp->sync_lock);
104 		error = hammer_reblock_helper(reblock, &cursor, elm);
105 		hammer_unlock(&trans->hmp->sync_lock);
106 		if (error == 0) {
107 			cursor.flags |= HAMMER_CURSOR_ATEDISK;
108 			error = hammer_btree_iterate(&cursor);
109 		}
110 
111 		/*
112 		 * Bad hack for now, don't blow out the kernel's buffer
113 		 * cache.
114 		 */
115 		if (trans->hmp->locked_dirty_count > hammer_limit_dirtybufs)
116 			hammer_flusher_sync(trans->hmp);
117 		if (error == 0)
118 			error = hammer_signal_check(trans->hmp);
119 	}
120 	if (error == ENOENT)
121 		error = 0;
122 	hammer_done_cursor(&cursor);
123 	if (error == EDEADLK)
124 		goto retry;
125 	return(error);
126 }
127 
128 /*
129  * Reblock the B-Tree (leaf) node, record, and/or data if necessary.
130  *
131  * XXX We have no visibility into internal B-Tree nodes at the moment,
132  * only leaf nodes.
133  */
134 static int
135 hammer_reblock_helper(struct hammer_ioc_reblock *reblock,
136 		      hammer_cursor_t cursor, hammer_btree_elm_t elm)
137 {
138 	hammer_off_t tmp_offset;
139 	int error;
140 	int zone;
141 	int bytes;
142 	int cur;
143 
144 	if (elm->leaf.base.btype != HAMMER_BTREE_TYPE_RECORD)
145 		return(0);
146 	error = 0;
147 
148 	/*
149 	 * Reblock data.  Note that data embedded in a record is reblocked
150 	 * by the record reblock code.
151 	 */
152 	tmp_offset = elm->leaf.data_offset;
153 	zone = HAMMER_ZONE_DECODE(tmp_offset);		/* can be 0 */
154 	if ((zone == HAMMER_ZONE_SMALL_DATA_INDEX ||
155 	     zone == HAMMER_ZONE_LARGE_DATA_INDEX) && error == 0) {
156 		++reblock->data_count;
157 		reblock->data_byte_count += elm->leaf.data_len;
158 		bytes = hammer_blockmap_getfree(cursor->trans->hmp, tmp_offset,
159 						&cur, &error);
160 		if (error == 0 && cur == 0 && bytes > reblock->free_level) {
161 			if (hammer_debug_general & 0x4000)
162 				kprintf("%6d ", bytes);
163 			error = hammer_cursor_upgrade(cursor);
164 			if (error == 0) {
165 				error = hammer_reblock_data(reblock,
166 							    cursor, elm);
167 			}
168 			if (error == 0) {
169 				++reblock->data_moves;
170 				reblock->data_byte_moves += elm->leaf.data_len;
171 			}
172 		}
173 	}
174 
175 	/*
176 	 * Reblock a record
177 	 */
178 	tmp_offset = elm->leaf.rec_offset;
179 	zone = HAMMER_ZONE_DECODE(tmp_offset);
180 	if (zone == HAMMER_ZONE_RECORD_INDEX && error == 0) {
181 		++reblock->record_count;
182 		bytes = hammer_blockmap_getfree(cursor->trans->hmp, tmp_offset,
183 						&cur, &error);
184 		if (error == 0 && cur == 0 && bytes > reblock->free_level) {
185 			if (hammer_debug_general & 0x4000)
186 				kprintf("%6d ", bytes);
187 			error = hammer_cursor_upgrade(cursor);
188 			if (error == 0) {
189 				error = hammer_reblock_record(reblock,
190 							      cursor, elm);
191 			}
192 			if (error == 0) {
193 				++reblock->record_moves;
194 			}
195 		}
196 	}
197 
198 	/*
199 	 * Reblock a B-Tree node.  Adjust elm to point at the parent's
200 	 * leaf entry.
201 	 */
202 	tmp_offset = cursor->node->node_offset;
203 	zone = HAMMER_ZONE_DECODE(tmp_offset);
204 	if (zone == HAMMER_ZONE_BTREE_INDEX && error == 0 &&
205 	    cursor->index == 0) {
206 		++reblock->btree_count;
207 		bytes = hammer_blockmap_getfree(cursor->trans->hmp, tmp_offset,
208 						&cur, &error);
209 		if (error == 0 && cur == 0 && bytes > reblock->free_level) {
210 			if (hammer_debug_general & 0x4000)
211 				kprintf("%6d ", bytes);
212 			error = hammer_cursor_upgrade(cursor);
213 			if (error == 0) {
214 				if (cursor->parent)
215 					elm = &cursor->parent->ondisk->elms[cursor->parent_index];
216 				else
217 					elm = NULL;
218 				error = hammer_reblock_node(reblock,
219 							    cursor, elm);
220 			}
221 			if (error == 0) {
222 				++reblock->btree_moves;
223 			}
224 		}
225 	}
226 
227 	hammer_cursor_downgrade(cursor);
228 	return(error);
229 }
230 
231 /*
232  * Reblock a record's data.  Both the B-Tree element and record pointers
233  * to the data must be adjusted.
234  */
235 static int
236 hammer_reblock_data(struct hammer_ioc_reblock *reblock,
237 		    hammer_cursor_t cursor, hammer_btree_elm_t elm)
238 {
239 	struct hammer_buffer *data_buffer = NULL;
240 	hammer_off_t ndata_offset;
241 	int error;
242 	void *ndata;
243 
244 	error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_DATA |
245 					     HAMMER_CURSOR_GET_RECORD);
246 	if (error)
247 		return (error);
248 	ndata = hammer_alloc_data(cursor->trans, elm->leaf.data_len,
249 				  &ndata_offset, &data_buffer, &error);
250 	if (error)
251 		goto done;
252 
253 	/*
254 	 * Move the data
255 	 */
256 	hammer_modify_buffer(cursor->trans, data_buffer, NULL, 0);
257 	bcopy(cursor->data, ndata, elm->leaf.data_len);
258 	hammer_modify_buffer_done(data_buffer);
259 
260 	hammer_blockmap_free(cursor->trans,
261 			     elm->leaf.data_offset, elm->leaf.data_len);
262 
263 	hammer_modify_record(cursor->trans, cursor->record_buffer,
264 			     &cursor->record->base.data_off,
265 			     sizeof(hammer_off_t));
266 	cursor->record->base.data_off = ndata_offset;
267 	hammer_modify_record_done(cursor->record_buffer);
268 
269 	hammer_modify_node(cursor->trans, cursor->node,
270 			   &elm->leaf.data_offset, sizeof(hammer_off_t));
271 	elm->leaf.data_offset = ndata_offset;
272 	hammer_modify_node_done(cursor->node);
273 
274 done:
275 	if (data_buffer)
276 		hammer_rel_buffer(data_buffer, 0);
277 	return (error);
278 }
279 
280 /*
281  * Reblock a record.  The B-Tree must be adjusted to point to the new record
282  * and the existing record must be physically destroyed so a FS rebuild
283  * does not see two versions of the same record.
284  */
285 static int
286 hammer_reblock_record(struct hammer_ioc_reblock *reblock,
287 		      hammer_cursor_t cursor, hammer_btree_elm_t elm)
288 {
289 	struct hammer_buffer *rec_buffer = NULL;
290 	hammer_off_t nrec_offset;
291 	hammer_off_t ndata_offset;
292 	hammer_record_ondisk_t orec;
293 	hammer_record_ondisk_t nrec;
294 	int error;
295 	int inline_data;
296 
297 	error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_RECORD);
298 	if (error)
299 		return (error);
300 
301 	nrec = hammer_alloc_record(cursor->trans, &nrec_offset,
302 				   elm->leaf.base.rec_type, &rec_buffer,
303 				   0, NULL, NULL, &error);
304 	if (error)
305 		goto done;
306 
307 	/*
308 	 * Move the record.  Check for an inline data reference and move that
309 	 * too if necessary.
310 	 */
311 	orec = cursor->record;
312 	hammer_modify_buffer(cursor->trans, rec_buffer, NULL, 0);
313 	bcopy(orec, nrec, sizeof(*nrec));
314 
315 	if ((orec->base.data_off & HAMMER_OFF_ZONE_MASK) == HAMMER_ZONE_RECORD) {
316 		ndata_offset = orec->base.data_off - elm->leaf.rec_offset;
317 		KKASSERT(ndata_offset < sizeof(*nrec));
318 		ndata_offset += nrec_offset;
319 		inline_data = 1;
320 	} else {
321 		ndata_offset = 0;
322 		inline_data = 0;
323 	}
324 
325 	hammer_modify_record(cursor->trans, cursor->record_buffer,
326 			     &orec->base.base.rec_type,
327 			     sizeof(orec->base.base.rec_type));
328 	orec->base.base.rec_type |= HAMMER_RECTYPE_MOVED;
329 	hammer_modify_record_done(cursor->record_buffer);
330 
331 	hammer_blockmap_free(cursor->trans,
332 			     elm->leaf.rec_offset, sizeof(*nrec));
333 
334 	if (hammer_debug_general & 0x4000) {
335 		kprintf("REBLOCK RECD %016llx -> %016llx\n",
336 			elm->leaf.rec_offset, nrec_offset);
337 	}
338 
339 	hammer_modify_node(cursor->trans, cursor->node,
340 			   &elm->leaf.rec_offset, sizeof(hammer_off_t));
341 	elm->leaf.rec_offset = nrec_offset;
342 	hammer_modify_node_done(cursor->node);
343 	if (inline_data) {
344 		hammer_modify_node(cursor->trans, cursor->node,
345 				 &elm->leaf.data_offset, sizeof(hammer_off_t));
346 		elm->leaf.data_offset = ndata_offset;
347 		hammer_modify_node_done(cursor->node);
348 		nrec->base.data_off = ndata_offset;
349 	}
350 	hammer_modify_buffer_done(rec_buffer);
351 
352 done:
353 	if (rec_buffer)
354 		hammer_rel_buffer(rec_buffer, 0);
355 	return (error);
356 }
357 
358 /*
359  * Reblock a B-Tree (leaf) node.  The parent must be adjusted to point to
360  * the new copy of the leaf node.  elm is a pointer to the parent element
361  * pointing at cursor.node.
362  *
363  * XXX reblock internal nodes too.
364  */
365 static int
366 hammer_reblock_node(struct hammer_ioc_reblock *reblock,
367 		    hammer_cursor_t cursor, hammer_btree_elm_t elm)
368 {
369 	hammer_node_t onode;
370 	hammer_node_t nnode;
371 	int error;
372 
373 	onode = cursor->node;
374 	nnode = hammer_alloc_btree(cursor->trans, &error);
375 	hammer_lock_ex(&nnode->lock);
376 
377 	if (nnode == NULL)
378 		return (error);
379 
380 	/*
381 	 * Move the node
382 	 */
383 	bcopy(onode->ondisk, nnode->ondisk, sizeof(*nnode->ondisk));
384 
385 	if (elm) {
386 		/*
387 		 * We are not the root of the B-Tree
388 		 */
389 		hammer_modify_node(cursor->trans, cursor->parent,
390 				   &elm->internal.subtree_offset,
391 				   sizeof(elm->internal.subtree_offset));
392 		elm->internal.subtree_offset = nnode->node_offset;
393 		hammer_modify_node_done(cursor->parent);
394 	} else {
395 		/*
396 		 * We are the root of the B-Tree
397 		 */
398                 hammer_volume_t volume;
399 
400                 volume = hammer_get_root_volume(cursor->trans->hmp, &error);
401                 KKASSERT(error == 0);
402 
403                 hammer_modify_volume(cursor->trans, volume,
404 				     &volume->ondisk->vol0_btree_root,
405                                      sizeof(hammer_off_t));
406                 volume->ondisk->vol0_btree_root = nnode->node_offset;
407                 hammer_modify_volume_done(volume);
408                 hammer_rel_volume(volume, 0);
409         }
410 
411 	hammer_delete_node(cursor->trans, onode);
412 
413 	if (hammer_debug_general & 0x4000) {
414 		kprintf("REBLOCK NODE %016llx -> %016llx\n",
415 			onode->node_offset, nnode->node_offset);
416 	}
417 
418 	cursor->node = nnode;
419 	hammer_rel_node(onode);
420 
421 	return (error);
422 }
423 
424