2 * Copyright (c) 2008 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
5 * by Matthew Dillon <dillon@backplane.com>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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
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.
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
34 * $DragonFly: src/sys/vfs/hammer/hammer_reblock.c,v 1.32.2.2 2008/08/02 21:24:28 dillon Exp $
37 * HAMMER reblocker - This code frees up fragmented physical space
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.
43 * This function is called from an ioctl or via the hammer support thread.
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_leaf_node(struct hammer_ioc_reblock
*reblock
,
54 hammer_cursor_t cursor
, hammer_btree_elm_t elm
);
55 static int hammer_reblock_int_node(struct hammer_ioc_reblock
*reblock
,
56 hammer_cursor_t cursor
, hammer_btree_elm_t elm
);
59 hammer_ioc_reblock(hammer_transaction_t trans
, hammer_inode_t ip
,
60 struct hammer_ioc_reblock
*reblock
)
62 struct hammer_cursor cursor
;
63 hammer_btree_elm_t elm
;
70 * A fill level <= 20% is considered an emergency. free_level is
71 * inverted from fill_level.
73 if (reblock
->free_level
>= HAMMER_LARGEBLOCK_SIZE
* 8 / 10)
74 slop
= HAMMER_CHKSPC_EMERGENCY
;
76 slop
= HAMMER_CHKSPC_REBLOCK
;
78 if ((reblock
->key_beg
.localization
| reblock
->key_end
.localization
) &
79 HAMMER_LOCALIZE_PSEUDOFS_MASK
) {
82 if (reblock
->key_beg
.obj_id
>= reblock
->key_end
.obj_id
)
84 if (reblock
->free_level
< 0)
87 reblock
->key_cur
= reblock
->key_beg
;
88 reblock
->key_cur
.localization
&= HAMMER_LOCALIZE_MASK
;
89 reblock
->key_cur
.localization
+= ip
->obj_localization
;
92 seq
= trans
->hmp
->flusher
.act
;
94 error
= hammer_init_cursor(trans
, &cursor
, NULL
, NULL
);
96 hammer_done_cursor(&cursor
);
99 cursor
.key_beg
.localization
= reblock
->key_cur
.localization
;
100 cursor
.key_beg
.obj_id
= reblock
->key_cur
.obj_id
;
101 cursor
.key_beg
.key
= HAMMER_MIN_KEY
;
102 cursor
.key_beg
.create_tid
= 1;
103 cursor
.key_beg
.delete_tid
= 0;
104 cursor
.key_beg
.rec_type
= HAMMER_MIN_RECTYPE
;
105 cursor
.key_beg
.obj_type
= 0;
107 cursor
.key_end
.localization
= (reblock
->key_end
.localization
&
108 HAMMER_LOCALIZE_MASK
) +
109 ip
->obj_localization
;
110 cursor
.key_end
.obj_id
= reblock
->key_end
.obj_id
;
111 cursor
.key_end
.key
= HAMMER_MAX_KEY
;
112 cursor
.key_end
.create_tid
= HAMMER_MAX_TID
- 1;
113 cursor
.key_end
.delete_tid
= 0;
114 cursor
.key_end
.rec_type
= HAMMER_MAX_RECTYPE
;
115 cursor
.key_end
.obj_type
= 0;
117 cursor
.flags
|= HAMMER_CURSOR_END_INCLUSIVE
;
118 cursor
.flags
|= HAMMER_CURSOR_BACKEND
;
121 * This flag allows the btree scan code to return internal nodes,
122 * so we can reblock them in addition to the leafs. Only specify it
123 * if we intend to reblock B-Tree nodes.
125 if (reblock
->head
.flags
& HAMMER_IOC_DO_BTREE
)
126 cursor
.flags
|= HAMMER_CURSOR_REBLOCKING
;
128 error
= hammer_btree_first(&cursor
);
131 * Internal or Leaf node
133 elm
= &cursor
.node
->ondisk
->elms
[cursor
.index
];
134 reblock
->key_cur
.obj_id
= elm
->base
.obj_id
;
135 reblock
->key_cur
.localization
= elm
->base
.localization
;
138 * Yield to more important tasks
140 if ((error
= hammer_signal_check(trans
->hmp
)) != 0)
144 * If there is insufficient free space it may be due to
145 * reserved bigblocks, which flushing might fix.
147 if (hammer_checkspace(trans
->hmp
, slop
)) {
148 if (++checkspace_count
== 10) {
152 hammer_unlock_cursor(&cursor
, 0);
153 hammer_flusher_wait(trans
->hmp
, seq
);
154 hammer_lock_cursor(&cursor
, 0);
155 seq
= hammer_flusher_async(trans
->hmp
, NULL
);
160 * Acquiring the sync_lock prevents the operation from
161 * crossing a synchronization boundary.
163 * NOTE: cursor.node may have changed on return.
165 hammer_sync_lock_sh(trans
);
166 error
= hammer_reblock_helper(reblock
, &cursor
, elm
);
167 hammer_sync_unlock(trans
);
169 while (hammer_flusher_meta_halflimit(trans
->hmp
) ||
170 hammer_flusher_undo_exhausted(trans
, 2)) {
171 hammer_unlock_cursor(&cursor
, 0);
172 hammer_flusher_wait(trans
->hmp
, seq
);
173 hammer_lock_cursor(&cursor
, 0);
174 seq
= hammer_flusher_async_one(trans
->hmp
);
178 * Setup for iteration, our cursor flags may be modified by
179 * other threads while we are unlocked.
181 cursor
.flags
|= HAMMER_CURSOR_ATEDISK
;
184 * We allocate data buffers, which atm we don't track
185 * dirty levels for because we allow the kernel to write
186 * them. But if we allocate too many we can still deadlock
189 * (The cursor's node and element may change!)
192 hammer_unlock_cursor(&cursor
, 0);
193 bwillwrite(HAMMER_XBUFSIZE
);
194 hammer_lock_cursor(&cursor
, 0);
198 error
= hammer_btree_iterate(&cursor
);
204 hammer_done_cursor(&cursor
);
205 if (error
== EWOULDBLOCK
) {
206 hammer_flusher_sync(trans
->hmp
);
209 if (error
== EDEADLK
)
211 if (error
== EINTR
) {
212 reblock
->head
.flags
|= HAMMER_IOC_HEAD_INTR
;
216 reblock
->key_cur
.localization
&= HAMMER_LOCALIZE_MASK
;
221 * Reblock the B-Tree (leaf) node, record, and/or data if necessary.
223 * XXX We have no visibility into internal B-Tree nodes at the moment,
227 hammer_reblock_helper(struct hammer_ioc_reblock
*reblock
,
228 hammer_cursor_t cursor
, hammer_btree_elm_t elm
)
231 hammer_off_t tmp_offset
;
238 hmp
= cursor
->trans
->hmp
;
241 * Reblock data. Note that data embedded in a record is reblocked
242 * by the record reblock code. Data processing only occurs at leaf
243 * nodes and for RECORD element types.
245 if (cursor
->node
->ondisk
->type
!= HAMMER_BTREE_TYPE_LEAF
)
247 if (elm
->leaf
.base
.btype
!= HAMMER_BTREE_TYPE_RECORD
)
249 tmp_offset
= elm
->leaf
.data_offset
;
256 * NOTE: Localization restrictions may also have been set-up, we can't
257 * just set the match flags willy-nilly here.
259 switch(elm
->leaf
.base
.rec_type
) {
260 case HAMMER_RECTYPE_INODE
:
261 iocflags
= HAMMER_IOC_DO_INODES
;
263 case HAMMER_RECTYPE_EXT
:
264 case HAMMER_RECTYPE_FIX
:
265 case HAMMER_RECTYPE_PFS
:
266 case HAMMER_RECTYPE_DIRENTRY
:
267 iocflags
= HAMMER_IOC_DO_DIRS
;
269 case HAMMER_RECTYPE_DATA
:
270 case HAMMER_RECTYPE_DB
:
271 iocflags
= HAMMER_IOC_DO_DATA
;
277 if (reblock
->head
.flags
& iocflags
) {
278 ++reblock
->data_count
;
279 reblock
->data_byte_count
+= elm
->leaf
.data_len
;
280 bytes
= hammer_blockmap_getfree(hmp
, tmp_offset
, &cur
, &error
);
281 if (hammer_debug_general
& 0x4000)
282 kprintf("D %6d/%d\n", bytes
, reblock
->free_level
);
283 if (error
== 0 && (cur
== 0 || reblock
->free_level
== 0) &&
284 bytes
>= reblock
->free_level
) {
285 hammer_io_direct_uncache(hmp
, &elm
->leaf
);
286 error
= hammer_cursor_upgrade(cursor
);
288 error
= hammer_reblock_data(reblock
,
292 ++reblock
->data_moves
;
293 reblock
->data_byte_moves
+= elm
->leaf
.data_len
;
300 * Reblock a B-Tree internal or leaf node.
302 tmp_offset
= cursor
->node
->node_offset
;
303 if (cursor
->index
== 0 &&
304 error
== 0 && (reblock
->head
.flags
& HAMMER_IOC_DO_BTREE
)) {
305 ++reblock
->btree_count
;
306 bytes
= hammer_blockmap_getfree(hmp
, tmp_offset
, &cur
, &error
);
307 if (hammer_debug_general
& 0x4000)
308 kprintf("B %6d/%d\n", bytes
, reblock
->free_level
);
309 if (error
== 0 && (cur
== 0 || reblock
->free_level
== 0) &&
310 bytes
>= reblock
->free_level
) {
311 error
= hammer_cursor_upgrade(cursor
);
314 elm
= &cursor
->parent
->ondisk
->elms
[cursor
->parent_index
];
317 switch(cursor
->node
->ondisk
->type
) {
318 case HAMMER_BTREE_TYPE_LEAF
:
319 error
= hammer_reblock_leaf_node(
320 reblock
, cursor
, elm
);
322 case HAMMER_BTREE_TYPE_INTERNAL
:
323 error
= hammer_reblock_int_node(
324 reblock
, cursor
, elm
);
327 panic("Illegal B-Tree node type");
331 ++reblock
->btree_moves
;
336 hammer_cursor_downgrade(cursor
);
341 * Reblock a record's data. Both the B-Tree element and record pointers
342 * to the data must be adjusted.
345 hammer_reblock_data(struct hammer_ioc_reblock
*reblock
,
346 hammer_cursor_t cursor
, hammer_btree_elm_t elm
)
348 struct hammer_buffer
*data_buffer
= NULL
;
349 hammer_off_t ndata_offset
;
353 error
= hammer_btree_extract(cursor
, HAMMER_CURSOR_GET_DATA
|
354 HAMMER_CURSOR_GET_LEAF
);
357 ndata
= hammer_alloc_data(cursor
->trans
, elm
->leaf
.data_len
,
358 elm
->leaf
.base
.rec_type
,
359 &ndata_offset
, &data_buffer
, &error
);
366 hammer_modify_buffer(cursor
->trans
, data_buffer
, NULL
, 0);
367 bcopy(cursor
->data
, ndata
, elm
->leaf
.data_len
);
368 hammer_modify_buffer_done(data_buffer
);
370 hammer_blockmap_free(cursor
->trans
,
371 elm
->leaf
.data_offset
, elm
->leaf
.data_len
);
373 hammer_modify_node(cursor
->trans
, cursor
->node
,
374 &elm
->leaf
.data_offset
, sizeof(hammer_off_t
));
375 elm
->leaf
.data_offset
= ndata_offset
;
376 hammer_modify_node_done(cursor
->node
);
380 hammer_rel_buffer(data_buffer
, 0);
385 * Reblock a B-Tree leaf node. The parent must be adjusted to point to
386 * the new copy of the leaf node.
388 * elm is a pointer to the parent element pointing at cursor.node.
391 hammer_reblock_leaf_node(struct hammer_ioc_reblock
*reblock
,
392 hammer_cursor_t cursor
, hammer_btree_elm_t elm
)
398 onode
= cursor
->node
;
399 nnode
= hammer_alloc_btree(cursor
->trans
, &error
);
407 hammer_lock_ex(&nnode
->lock
);
408 hammer_modify_node_noundo(cursor
->trans
, nnode
);
409 bcopy(onode
->ondisk
, nnode
->ondisk
, sizeof(*nnode
->ondisk
));
413 * We are not the root of the B-Tree
415 hammer_modify_node(cursor
->trans
, cursor
->parent
,
416 &elm
->internal
.subtree_offset
,
417 sizeof(elm
->internal
.subtree_offset
));
418 elm
->internal
.subtree_offset
= nnode
->node_offset
;
419 hammer_modify_node_done(cursor
->parent
);
422 * We are the root of the B-Tree
424 hammer_volume_t volume
;
426 volume
= hammer_get_root_volume(cursor
->trans
->hmp
, &error
);
427 KKASSERT(error
== 0);
429 hammer_modify_volume_field(cursor
->trans
, volume
,
431 volume
->ondisk
->vol0_btree_root
= nnode
->node_offset
;
432 hammer_modify_volume_done(volume
);
433 hammer_rel_volume(volume
, 0);
436 hammer_cursor_replaced_node(onode
, nnode
);
437 hammer_delete_node(cursor
->trans
, onode
);
439 if (hammer_debug_general
& 0x4000) {
440 kprintf("REBLOCK LNODE %016llx -> %016llx\n",
441 onode
->node_offset
, nnode
->node_offset
);
443 hammer_modify_node_done(nnode
);
444 cursor
->node
= nnode
;
446 hammer_unlock(&onode
->lock
);
447 hammer_rel_node(onode
);
453 * Reblock a B-Tree internal node. The parent must be adjusted to point to
454 * the new copy of the internal node, and the node's children's parent
455 * pointers must also be adjusted to point to the new copy.
457 * elm is a pointer to the parent element pointing at cursor.node.
460 hammer_reblock_int_node(struct hammer_ioc_reblock
*reblock
,
461 hammer_cursor_t cursor
, hammer_btree_elm_t elm
)
463 hammer_node_locklist_t locklist
= NULL
;
469 error
= hammer_btree_lock_children(cursor
, &locklist
);
473 onode
= cursor
->node
;
474 nnode
= hammer_alloc_btree(cursor
->trans
, &error
);
480 * Move the node. Adjust the parent's pointer to us first.
482 hammer_lock_ex(&nnode
->lock
);
483 hammer_modify_node_noundo(cursor
->trans
, nnode
);
484 bcopy(onode
->ondisk
, nnode
->ondisk
, sizeof(*nnode
->ondisk
));
488 * We are not the root of the B-Tree
490 hammer_modify_node(cursor
->trans
, cursor
->parent
,
491 &elm
->internal
.subtree_offset
,
492 sizeof(elm
->internal
.subtree_offset
));
493 elm
->internal
.subtree_offset
= nnode
->node_offset
;
494 hammer_modify_node_done(cursor
->parent
);
497 * We are the root of the B-Tree
499 hammer_volume_t volume
;
501 volume
= hammer_get_root_volume(cursor
->trans
->hmp
, &error
);
502 KKASSERT(error
== 0);
504 hammer_modify_volume_field(cursor
->trans
, volume
,
506 volume
->ondisk
->vol0_btree_root
= nnode
->node_offset
;
507 hammer_modify_volume_done(volume
);
508 hammer_rel_volume(volume
, 0);
512 * Now adjust our children's pointers to us.
514 for (i
= 0; i
< nnode
->ondisk
->count
; ++i
) {
515 elm
= &nnode
->ondisk
->elms
[i
];
516 error
= btree_set_parent(cursor
->trans
, nnode
, elm
);
518 panic("reblock internal node: fixup problem");
524 * The new node replaces the current node in the cursor. The cursor
525 * expects it to be locked so leave it locked. Discard onode.
527 hammer_cursor_replaced_node(onode
, nnode
);
528 hammer_delete_node(cursor
->trans
, onode
);
530 if (hammer_debug_general
& 0x4000) {
531 kprintf("REBLOCK INODE %016llx -> %016llx\n",
532 onode
->node_offset
, nnode
->node_offset
);
534 hammer_modify_node_done(nnode
);
535 cursor
->node
= nnode
;
537 hammer_unlock(&onode
->lock
);
538 hammer_rel_node(onode
);
541 hammer_btree_unlock_children(&locklist
);