hammer2 - more indirect block work, add advlock
[dragonfly.git] / sys / vfs / hammer2 / hammer2_chain.c
CommitLineData
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1/*
2 * Copyright (c) 2011-2012 The DragonFly Project. All rights reserved.
3 *
4 * This code is derived from software contributed to The DragonFly Project
5 * by Matthew Dillon <dillon@dragonflybsd.org>
6 * by Venkatesh Srinivas <vsrinivas@dragonflybsd.org>
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
17 * distribution.
18 * 3. Neither the name of The DragonFly Project nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific, prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
32 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
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35/*
36 * This subsystem handles direct and indirect block searches, recursions,
37 * creation, and deletion. Chains of blockrefs are tracked and modifications
38 * are flag for propagation... eventually all the way back to the volume
39 * header.
40 */
41
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42#include <sys/cdefs.h>
43#include <sys/cdefs.h>
44#include <sys/param.h>
45#include <sys/systm.h>
46#include <sys/types.h>
47#include <sys/lock.h>
48#include <sys/uuid.h>
49
50#include "hammer2.h"
51
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52SPLAY_GENERATE(hammer2_chain_splay, hammer2_chain, snode, hammer2_chain_cmp);
53
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54static int hammer2_indirect_optimize; /* XXX SYSCTL */
55
56static hammer2_chain_t *hammer2_chain_create_indirect(
57 hammer2_mount_t *hmp, hammer2_chain_t *parent,
58 hammer2_key_t key, int keybits);
59
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60/*
61 * Compare function for chain splay tree
62 */
63int
64hammer2_chain_cmp(hammer2_chain_t *chain1, hammer2_chain_t *chain2)
65{
66 return(chain2->index - chain1->index);
67}
68
69/*
70 * Allocate a new disconnected chain element representing the specified
37494cab 71 * bref. The chain element is locked exclusively and refs is set to 1.
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72 *
73 * This essentially allocates a system memory structure representing one
74 * of the media structure types, including inodes.
75 */
76hammer2_chain_t *
77hammer2_chain_alloc(hammer2_mount_t *hmp, hammer2_blockref_t *bref)
78{
79 hammer2_chain_t *chain;
80 hammer2_inode_t *ip;
81 hammer2_indblock_t *np;
82 hammer2_data_t *dp;
83
84 /*
85 * Construct the appropriate system structure.
86 */
87 switch(bref->type) {
88 case HAMMER2_BREF_TYPE_INODE:
89 ip = kmalloc(sizeof(*ip), hmp->minode, M_WAITOK | M_ZERO);
90 chain = &ip->chain;
91 chain->u.ip = ip;
92 lockinit(&chain->lk, "inode", 0, LK_CANRECURSE);
93 ip->hmp = hmp;
94 break;
95 case HAMMER2_BREF_TYPE_INDIRECT:
96 np = kmalloc(sizeof(*np), hmp->mchain, M_WAITOK | M_ZERO);
97 chain = &np->chain;
98 chain->u.np = np;
99 lockinit(&chain->lk, "iblk", 0, LK_CANRECURSE);
100 break;
101 case HAMMER2_BREF_TYPE_DATA:
102 dp = kmalloc(sizeof(*dp), hmp->mchain, M_WAITOK | M_ZERO);
103 chain = &dp->chain;
104 chain->u.dp = dp;
105 lockinit(&chain->lk, "dblk", 0, LK_CANRECURSE);
106 break;
107 case HAMMER2_BREF_TYPE_VOLUME:
108 chain = NULL;
109 panic("hammer2_chain_get: volume type illegal for op");
110 default:
111 chain = NULL;
112 panic("hammer2_chain_get: unrecognized blockref type: %d",
113 bref->type);
114 }
115 chain->bref = *bref;
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116 chain->index = -1; /* not yet assigned */
117
5c23d7f1 118 chain->refs = 1;
37494cab 119 lockmgr(&chain->lk, LK_EXCLUSIVE);
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120
121 return (chain);
122}
123
124/*
125 * Free a disconnected chain element
126 */
127void
128hammer2_chain_free(hammer2_mount_t *hmp, hammer2_chain_t *chain)
129{
130 void *mem;
131
132 KKASSERT(chain->bp == NULL);
133 KKASSERT(chain->data == NULL);
134 KKASSERT(chain->bref.type != HAMMER2_BREF_TYPE_INODE ||
135 chain->u.ip->vp == NULL);
136
137 if ((mem = chain->u.mem) != NULL) {
138 chain->u.mem = NULL;
139 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE)
140 kfree(mem, hmp->minode);
141 else
142 kfree(mem, hmp->mchain);
143 }
144}
145
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146/*
147 * Add a reference to a chain element (for shared access). The chain
5c23d7f1 148 * element must already have at least 1 ref controlled by the caller.
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149 */
150void
151hammer2_chain_ref(hammer2_mount_t *hmp, hammer2_chain_t *chain)
152{
153 KKASSERT(chain->refs > 0);
154 atomic_add_int(&chain->refs, 1);
155}
156
157/*
158 * Drop the callers reference to the chain element. If the ref count
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159 * reaches zero the chain element and its related structure (typically an
160 * inode or indirect block) will be freed and the parent will be
161 * recursively dropped.
162 *
163 * Modified elements hold an additional reference so it should not be
164 * possible for the count on a modified element to drop to 0.
165 *
166 * The chain element must NOT be locked by the caller.
7cfa8da5 167 *
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168 * The parent might or might not be locked by the caller but if so it
169 * will also be referenced so we shouldn't recurse upward.
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170 */
171void
172hammer2_chain_drop(hammer2_mount_t *hmp, hammer2_chain_t *chain)
173{
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174 hammer2_chain_t *parent;
175 u_int refs;
176
177 while (chain) {
178 refs = chain->refs;
179 cpu_ccfence();
180 if (refs == 1) {
181 KKASSERT(chain != &hmp->vchain);
182 parent = chain->parent;
183 lockmgr(&parent->lk, LK_EXCLUSIVE);
184 if (atomic_cmpset_int(&chain->refs, 1, 0)) {
185 /*
186 * Succeeded, recurse and drop parent
187 */
188 SPLAY_REMOVE(hammer2_chain_splay,
189 &parent->shead, chain);
190 chain->parent = NULL;
191 lockmgr(&parent->lk, LK_RELEASE);
192 hammer2_chain_free(hmp, chain);
193 chain = parent;
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194 } else {
195 lockmgr(&parent->lk, LK_RELEASE);
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196 }
197 } else {
198 if (atomic_cmpset_int(&chain->refs, refs, refs - 1)) {
199 /*
200 * Succeeded, count did not reach zero so
201 * cut out of the loop.
202 */
203 break;
204 }
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205 }
206 }
207}
208
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209/*
210 * Lock a chain element, acquiring its data with I/O if necessary.
211 *
212 * Returns 0 on success or an error code if the data could not be acquired.
213 * The chain element is locked either way.
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214 *
215 * chain->data will be pointed either at the embedded data (e.g. for
216 * inodes), in which case the buffer cache buffer is released, or will
217 * point into the bp->b_data buffer with the bp left intact while locked.
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218 */
219int
220hammer2_chain_lock(hammer2_mount_t *hmp, hammer2_chain_t *chain)
232a50f9 221{
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222 hammer2_blockref_t *bref;
223 hammer2_off_t off_hi;
224 size_t off_lo;
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225 int error;
226 void *data;
227
228 /*
229 * Lock the element. Under certain conditions this might end up
230 * being a recursive lock.
231 */
232 KKASSERT(chain->refs > 0);
233 lockmgr(&chain->lk, LK_EXCLUSIVE);
234
235 /*
236 * The volume header is a special case
237 */
238 if (chain->bref.type == HAMMER2_BREF_TYPE_VOLUME)
239 return(0);
240
241 /*
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242 * bp must be NULL, so if the data pointer is valid here it points
243 * to embedded data and no I/O is necessary (whether modified or not).
5c23d7f1 244 */
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245 KKASSERT(chain->bp == NULL);
246 if (chain->data)
5c23d7f1 247 return (0);
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248
249 /*
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250 * If data is NULL we must issue I/O. Any error returns the error
251 * code but leaves the chain locked.
252 *
253 * If the chain was modified a new bref will have already been
254 * allocated and its related bp is probably still sitting in the
255 * buffer cache.
5c23d7f1 256 */
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257 bref = &chain->bref;
258
259 off_hi = bref->data_off & HAMMER2_OFF_MASK_HI;
260 off_lo = (size_t)bref->data_off & HAMMER2_OFF_MASK_LO;
5c23d7f1 261 KKASSERT(off_hi != 0);
b7926f31 262 error = bread(hmp->devvp, off_hi, HAMMER2_PBUFSIZE, &chain->bp);
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263
264 if (error) {
265 kprintf("hammer2_chain_get: I/O error %016jx: %d\n",
266 (intmax_t)off_hi, error);
267 brelse(chain->bp);
268 chain->bp = NULL;
269 return (error);
270 }
271
272 /*
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273 * Setup the data pointer, either pointing it to an embedded data
274 * structure and copying the data from the buffer, or pointint it
275 * into the buffer.
5c23d7f1 276 *
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277 * The buffer is not retained when copying to an embedded data
278 * structure in order to avoid potential deadlocks or recursions
279 * on the same physical buffer.
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280 */
281 switch (bref->type) {
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282 case HAMMER2_BREF_TYPE_VOLUME:
283 /*
284 * Copy data from bp to embedded buffer
285 */
286 KKASSERT(0); /* not yet - have mount use this soon */
287 KKASSERT(off_hi == 0);
288 bcopy((char *)chain->bp->b_data + off_lo,
289 &hmp->voldata, HAMMER2_PBUFSIZE);
290 chain->data = (void *)&hmp->voldata;
291 brelse(chain->bp);
292 chain->bp = NULL;
293 break;
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294 case HAMMER2_BREF_TYPE_INODE:
295 /*
296 * Copy data from bp to embedded buffer.
297 */
298 bcopy((char *)chain->bp->b_data + off_lo,
299 &chain->u.ip->ip_data,
300 HAMMER2_INODE_BYTES);
301 chain->data = (void *)&chain->u.ip->ip_data;
302 brelse(chain->bp);
303 chain->bp = NULL;
304 break;
305 default:
306 /*
307 * Leave bp intact
308 */
309 data = (char *)chain->bp->b_data + off_lo;
310 chain->data = data;
311 break;
312 }
313 return (0);
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314}
315
316/*
5c23d7f1 317 * Convert a locked chain that was retrieved read-only to read-write.
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318 *
319 * If not already marked modified a new physical block will be allocated
320 * and assigned to the bref. If the data is pointing into an existing
321 * bp it will be copied to the new bp and the new bp will replace the
322 * existing bp.
323 *
324 * If the data is embedded we allocate the new physical block but don't
325 * bother copying the data into it (yet).
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326 */
327void
5c23d7f1 328hammer2_chain_modify(hammer2_mount_t *hmp, hammer2_chain_t *chain)
232a50f9 329{
5c23d7f1 330 hammer2_chain_t *parent;
db71f61f 331 struct buf *nbp;
5c23d7f1 332 size_t bytes;
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333 void *ndata;
334 int error;
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335
336 /*
db71f61f 337 * If the chain is already marked modified we can just return.
5c23d7f1 338 */
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339 if (chain->flags & HAMMER2_CHAIN_MODIFIED) {
340 KKASSERT(chain->data != NULL);
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341 return;
342 }
343
344 /*
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345 * The MODIFIED bit is not yet set, we must allocate the
346 * copy-on-write block.
347 *
348 * If the data is embedded no other action is required.
349 *
350 * If the data is not embedded we acquire and clear the
351 * new block. If chain->data is not NULL we then do the
352 * copy-on-write. chain->data will then be repointed to the new
353 * buffer and the old buffer will be released.
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354 *
355 * For newly created elements with no prior allocation we go
356 * through the copy-on-write steps except without the copying part.
5c23d7f1 357 */
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358 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MODIFIED);
359 hammer2_chain_ref(hmp, chain); /* ref for modified bit */
5c23d7f1 360
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361 bytes = 1 << (int)(chain->bref.data_off & HAMMER2_OFF_MASK_RADIX);
362 if (chain != &hmp->vchain) {
363 chain->bref.data_off = hammer2_freemap_alloc(hmp, bytes);
364 /* XXX failed allocation */
365 }
5c23d7f1 366
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367 switch(chain->bref.type) {
368 case HAMMER2_BREF_TYPE_VOLUME: /* embedded */
369 case HAMMER2_BREF_TYPE_INODE: /* embedded */
5c23d7f1 370 /*
db71f61f 371 * data points to embedded structure, no copy needed
5c23d7f1 372 */
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373 error = 0;
374 break;
375 case HAMMER2_BREF_TYPE_INDIRECT:
376 case HAMMER2_BREF_TYPE_DATA:
377 /*
378 * data (if not NULL) points into original bp, copy-on-write
379 * to new block.
380 */
381 KKASSERT(chain != &hmp->vchain); /* safety */
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382 if (bytes == HAMMER2_PBUFSIZE) {
383 nbp = getblk(hmp->devvp,
384 chain->bref.data_off & HAMMER2_OFF_MASK_HI,
385 HAMMER2_PBUFSIZE, 0, 0);
386 vfs_bio_clrbuf(nbp);
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387 error = 0;
388 } else {
389 error = bread(hmp->devvp,
390 chain->bref.data_off & HAMMER2_OFF_MASK_HI,
391 HAMMER2_PBUFSIZE, &nbp);
392 KKASSERT(error == 0);/* XXX handle error */
232a50f9 393 }
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394 ndata = nbp->b_data + (chain->bref.data_off &
395 HAMMER2_OFF_MASK_LO);
396 if (chain->data) {
397 bcopy(chain->data, ndata, bytes);
398 KKASSERT(chain->bp != NULL);
399 brelse(chain->bp);
400 }
401 chain->bp = nbp;
402 chain->data = ndata;
403 break;
404 default:
405 panic("hammer2_chain_modify: unknown bref type");
406 break;
407
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408 }
409
410 /*
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411 * Recursively mark the parent chain elements so flushes can find
412 * modified elements.
5c23d7f1 413 */
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414 parent = chain->parent;
415 while (parent && (parent->flags & HAMMER2_CHAIN_SUBMODIFIED) == 0) {
416 atomic_set_int(&parent->flags, HAMMER2_CHAIN_SUBMODIFIED);
417 parent = parent->parent;
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418 }
419}
420
421/*
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422 * Unlock a chain element without dropping its reference count.
423 * (see hammer2_chain_put() to do both).
232a50f9 424 *
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425 * Non-embedded data references (chain->bp != NULL) are returned to the
426 * system and the data field is cleared in that case. If modified the
427 * dirty buffer is still returned to the system, can be flushed to disk by
428 * the system at any time, and will be reconstituted/re-read as needed.
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429 */
430void
431hammer2_chain_unlock(hammer2_mount_t *hmp, hammer2_chain_t *chain)
432{
433 if (chain->bp) {
434 chain->data = NULL;
c667909f 435 if (chain->flags & (HAMMER2_CHAIN_MODIFIED |
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436 HAMMER2_CHAIN_FLUSHED)) {
437 if (chain->flags & HAMMER2_CHAIN_IOFLUSH)
438 bawrite(chain->bp);
439 else
440 bdwrite(chain->bp);
441 } else {
c667909f 442 bqrelse(chain->bp);
37aa19df 443 }
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444 chain->bp = NULL;
445 }
446 lockmgr(&chain->lk, LK_RELEASE);
447}
448
449/*
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450 * Locate an in-memory chain. The parent must be locked. The in-memory
451 * chain is returned or NULL if no in-memory chain is present.
452 *
453 * NOTE: A chain on-media might exist for this index when NULL is returned.
454 */
455hammer2_chain_t *
456hammer2_chain_find(hammer2_mount_t *hmp, hammer2_chain_t *parent, int index)
457{
458 hammer2_chain_t dummy;
459 hammer2_chain_t *chain;
460
461 dummy.index = index;
462 chain = SPLAY_FIND(hammer2_chain_splay, &parent->shead, &dummy);
463 return (chain);
464}
465
466/*
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467 * Return a locked chain structure with all associated data acquired.
468 *
5c23d7f1 469 * Caller must lock the parent on call, the returned child will be locked.
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470 */
471hammer2_chain_t *
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472hammer2_chain_get(hammer2_mount_t *hmp, hammer2_chain_t *parent,
473 int index, int flags)
232a50f9 474{
5c23d7f1 475 hammer2_blockref_t *bref;
232a50f9 476 hammer2_chain_t *chain;
5c23d7f1 477 hammer2_chain_t dummy;
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478
479 /*
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480 * First see if we have a (possibly modified) chain element cached
481 * for this (parent, index). Acquire the data if necessary.
482 *
483 * If chain->data is non-NULL the chain should already be marked
484 * modified.
232a50f9 485 */
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486 dummy.index = index;
487 chain = SPLAY_FIND(hammer2_chain_splay, &parent->shead, &dummy);
488 if (chain) {
489 hammer2_chain_ref(hmp, chain);
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490 if ((flags & HAMMER2_LOOKUP_NOLOCK) == 0)
491 hammer2_chain_lock(hmp, chain);
5c23d7f1 492 return(chain);
232a50f9 493 }
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494
495 /*
db71f61f 496 * Otherwise lookup the bref and issue I/O (switch on the parent)
232a50f9 497 */
5c23d7f1 498 switch(parent->bref.type) {
232a50f9 499 case HAMMER2_BREF_TYPE_INODE:
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500 KKASSERT(index >= 0 && index < HAMMER2_SET_COUNT);
501 bref = &parent->data->ipdata.u.blockset.blockref[index];
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502 break;
503 case HAMMER2_BREF_TYPE_INDIRECT:
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504 KKASSERT(index >= 0 && index < HAMMER2_IND_COUNT);
505 bref = &parent->data->npdata.blockref[index];
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506 break;
507 case HAMMER2_BREF_TYPE_VOLUME:
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508 KKASSERT(index >= 0 && index < HAMMER2_SET_COUNT);
509 bref = &hmp->voldata.sroot_blockset.blockref[index];
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510 break;
511 default:
5c23d7f1 512 bref = NULL;
232a50f9 513 panic("hammer2_chain_get: unrecognized blockref type: %d",
5c23d7f1 514 parent->bref.type);
232a50f9 515 }
5c23d7f1 516 chain = hammer2_chain_alloc(hmp, bref);
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517
518 /*
519 * Link the chain into its parent. Caller is expected to hold an
520 * exclusive lock on the parent.
521 */
522 chain->parent = parent;
523 chain->index = index;
524 if (SPLAY_INSERT(hammer2_chain_splay, &parent->shead, chain))
525 panic("hammer2_chain_link: collision");
526 KKASSERT(parent->refs > 1);
5b4a2132 527 atomic_add_int(&parent->refs, 1); /* for splay entry */
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528
529 /*
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530 * Additional linkage for inodes. Reuse the parent pointer to
531 * find the parent directory.
532 */
533 if (bref->type == HAMMER2_BREF_TYPE_INODE) {
534 while (parent->bref.type == HAMMER2_BREF_TYPE_INDIRECT)
535 parent = parent->parent;
536 if (parent->bref.type == HAMMER2_BREF_TYPE_INODE)
537 chain->u.ip->pip = parent->u.ip;
538 }
539
540 /*
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541 * Our new chain structure has already been referenced and locked
542 * but the lock code handles the I/O so call it to resolve the data.
543 * Then release one of our two exclusive locks.
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544 *
545 * If NOLOCK is set the release will release the one-and-only lock.
5c23d7f1 546 */
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547 if ((flags & HAMMER2_LOOKUP_NOLOCK) == 0)
548 hammer2_chain_lock(hmp, chain);
5c23d7f1 549 lockmgr(&chain->lk, LK_RELEASE);
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550
551 return (chain);
552}
553
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554/*
555 * Unlock and dereference a chain after use. It is possible for this to
556 * recurse up the chain.
557 */
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558void
559hammer2_chain_put(hammer2_mount_t *hmp, hammer2_chain_t *chain)
560{
5c23d7f1 561 hammer2_chain_unlock(hmp, chain);
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562 hammer2_chain_drop(hmp, chain);
563}
564
7cfa8da5 565/*
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566 * Locate any key between key_beg and key_end inclusive. (*parentp)
567 * typically points to an inode but can also point to a related indirect
568 * block and this function will recurse upwards and find the inode again.
5c23d7f1 569 *
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570 * WARNING! THIS DOES NOT RETURN KEYS IN LOGICAL KEY ORDER! ANY KEY
571 * WITHIN THE RANGE CAN BE RETURNED. HOWEVER, AN ITERATION
572 * WHICH PICKS UP WHERE WE LEFT OFF WILL CONTINUE THE SCAN.
573 *
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574 * (*parentp) must be exclusively locked and referenced and can be an inode
575 * or an existing indirect block within the inode.
576 *
577 * On return (*parentp) will be modified to point at the deepest parent chain
578 * element encountered during the search, as a helper for an insertion or
579 * deletion. The new (*parentp) will be locked and referenced and the old
580 * will be unlocked and dereferenced (no change if they are both the same).
581 *
582 * The matching chain will be returned exclusively locked and referenced.
583 *
584 * NULL is returned if no match was found, but (*parentp) will still
585 * potentially be adjusted.
586 *
587 * This function will also recurse up the chain if the key is not within the
588 * current parent's range. (*parentp) can never be set to NULL. An iteration
589 * can simply allow (*parentp) to float inside the loop.
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590 */
591hammer2_chain_t *
5c23d7f1 592hammer2_chain_lookup(hammer2_mount_t *hmp, hammer2_chain_t **parentp,
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MD
593 hammer2_key_t key_beg, hammer2_key_t key_end,
594 int flags)
7cfa8da5 595{
5c23d7f1 596 hammer2_chain_t *parent;
232a50f9 597 hammer2_chain_t *chain;
b7926f31 598 hammer2_chain_t *tmp;
5c23d7f1 599 hammer2_blockref_t *base;
232a50f9 600 hammer2_blockref_t *bref;
e028fa74
MD
601 hammer2_key_t scan_beg;
602 hammer2_key_t scan_end;
232a50f9 603 int count = 0;
232a50f9
MD
604 int i;
605
232a50f9 606 /*
e028fa74
MD
607 * Recurse (*parentp) upward if necessary until the parent completely
608 * encloses the key range or we hit the inode.
5c23d7f1
MD
609 */
610 parent = *parentp;
611 while (parent->bref.type == HAMMER2_BREF_TYPE_INDIRECT) {
e028fa74
MD
612 scan_beg = parent->bref.key;
613 scan_end = scan_beg +
614 ((hammer2_key_t)1 << parent->bref.keybits) - 1;
615 if (key_beg >= scan_beg && key_end <= scan_end)
5c23d7f1
MD
616 break;
617 hammer2_chain_unlock(hmp, parent);
618 parent = parent->parent;
619 hammer2_chain_ref(hmp, parent); /* ref new parent */
620 hammer2_chain_lock(hmp, parent); /* lock new parent */
621 hammer2_chain_drop(hmp, *parentp); /* drop old parent */
622 *parentp = parent; /* new parent */
623 }
624
625again:
626 /*
627 * Locate the blockref array. Currently we do a fully associative
628 * search through the array.
232a50f9
MD
629 */
630 switch(parent->bref.type) {
631 case HAMMER2_BREF_TYPE_INODE:
5c23d7f1
MD
632 base = &parent->data->ipdata.u.blockset.blockref[0];
633 count = HAMMER2_SET_COUNT;
232a50f9
MD
634 break;
635 case HAMMER2_BREF_TYPE_INDIRECT:
5b4a2132
MD
636 if (parent->data == NULL)
637 panic("parent->data is NULL");
5c23d7f1
MD
638 base = &parent->data->npdata.blockref[0];
639 count = HAMMER2_IND_COUNT;
232a50f9
MD
640 break;
641 case HAMMER2_BREF_TYPE_VOLUME:
5c23d7f1
MD
642 base = &hmp->voldata.sroot_blockset.blockref[0];
643 count = HAMMER2_SET_COUNT;
232a50f9
MD
644 break;
645 default:
646 panic("hammer2_chain_push: unrecognized blockref type: %d",
647 parent->bref.type);
5c23d7f1
MD
648 base = NULL; /* safety */
649 count = 0; /* safety */
232a50f9
MD
650 }
651
5c23d7f1 652 /*
e028fa74 653 * If the element and key overlap we use the element.
5c23d7f1
MD
654 */
655 bref = NULL;
656 for (i = 0; i < count; ++i) {
b7926f31
MD
657 tmp = hammer2_chain_find(hmp, parent, i);
658 bref = (tmp) ? &tmp->bref : &base[i];
c667909f
MD
659 if (bref->type == 0)
660 continue;
e028fa74
MD
661 scan_beg = bref->key;
662 scan_end = scan_beg + ((hammer2_key_t)1 << bref->keybits) - 1;
663 if (key_beg <= scan_end && key_end >= scan_beg)
232a50f9 664 break;
232a50f9 665 }
5c23d7f1 666 if (i == count) {
e028fa74 667 if (key_beg == key_end)
5c23d7f1 668 return (NULL);
e028fa74 669 return (hammer2_chain_next(hmp, parentp, NULL,
c667909f 670 key_beg, key_end, flags));
5c23d7f1
MD
671 }
672
673 /*
674 * Acquire the new chain element. If the chain element is an
675 * indirect block we must search recursively.
676 */
c667909f 677 chain = hammer2_chain_get(hmp, parent, i, flags);
5c23d7f1
MD
678 if (chain == NULL)
679 return (NULL);
680
681 /*
682 * If the chain element is an indirect block it becomes the new
5b4a2132
MD
683 * parent and we loop on it. We must fixup the chain we loop on
684 * if the caller passed flags to us that aren't sufficient for our
685 * needs.
5c23d7f1
MD
686 */
687 if (chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT) {
688 hammer2_chain_put(hmp, parent);
689 *parentp = parent = chain;
5b4a2132
MD
690 if (flags & HAMMER2_LOOKUP_NOLOCK)
691 hammer2_chain_lock(hmp, chain);
5c23d7f1
MD
692 goto again;
693 }
694
695 /*
696 * All done, return chain
697 */
232a50f9 698 return (chain);
7cfa8da5
MD
699}
700
701/*
5c23d7f1
MD
702 * After having issued a lookup we can iterate all matching keys.
703 *
704 * If chain is non-NULL we continue the iteration from just after it's index.
705 *
706 * If chain is NULL we assume the parent was exhausted and continue the
707 * iteration at the next parent.
7cfa8da5
MD
708 */
709hammer2_chain_t *
5c23d7f1
MD
710hammer2_chain_next(hammer2_mount_t *hmp, hammer2_chain_t **parentp,
711 hammer2_chain_t *chain,
c667909f
MD
712 hammer2_key_t key_beg, hammer2_key_t key_end,
713 int flags)
7cfa8da5 714{
5c23d7f1 715 hammer2_chain_t *parent;
b7926f31 716 hammer2_chain_t *tmp;
5c23d7f1 717 hammer2_blockref_t *base;
232a50f9 718 hammer2_blockref_t *bref;
e028fa74
MD
719 hammer2_key_t scan_beg;
720 hammer2_key_t scan_end;
232a50f9 721 int i;
5c23d7f1
MD
722 int count;
723
724 parent = *parentp;
232a50f9 725
5c23d7f1
MD
726again:
727 /*
728 * Calculate the next index and recalculate the parent if necessary.
729 */
730 if (chain) {
731 /*
732 * Continue iteration within current parent
733 */
734 i = chain->index + 1;
735 hammer2_chain_put(hmp, chain);
736 chain = NULL;
737 } else if (parent->bref.type != HAMMER2_BREF_TYPE_INDIRECT) {
738 /*
739 * We reached the end of the iteration.
740 */
741 return (NULL);
742 } else {
743 /*
37aa19df
MD
744 * Continue iteration with next parent unless the current
745 * parent covers the range.
5c23d7f1 746 */
995e78dc
MD
747 hammer2_chain_t *nparent;
748
5c23d7f1
MD
749 if (parent->bref.type != HAMMER2_BREF_TYPE_INDIRECT)
750 return (NULL);
37aa19df
MD
751
752 scan_beg = parent->bref.key;
753 scan_end = scan_beg +
754 ((hammer2_key_t)1 << parent->bref.keybits) - 1;
755 if (key_beg >= scan_beg && key_end <= scan_end)
756 return (NULL);
757
5c23d7f1 758 i = parent->index + 1;
995e78dc
MD
759 nparent = parent->parent;
760 hammer2_chain_ref(hmp, nparent); /* ref new parent */
5c23d7f1 761 hammer2_chain_unlock(hmp, parent);
5b4a2132
MD
762 hammer2_chain_lock(hmp, nparent); /* lock new parent */
763 hammer2_chain_drop(hmp, parent); /* drop old parent */
764 *parentp = parent = nparent;
5c23d7f1 765 }
232a50f9 766
5c23d7f1 767again2:
232a50f9 768 /*
5c23d7f1
MD
769 * Locate the blockref array. Currently we do a fully associative
770 * search through the array.
232a50f9
MD
771 */
772 switch(parent->bref.type) {
773 case HAMMER2_BREF_TYPE_INODE:
5c23d7f1
MD
774 base = &parent->data->ipdata.u.blockset.blockref[0];
775 count = HAMMER2_SET_COUNT;
232a50f9
MD
776 break;
777 case HAMMER2_BREF_TYPE_INDIRECT:
5c23d7f1
MD
778 base = &parent->data->npdata.blockref[0];
779 count = HAMMER2_IND_COUNT;
232a50f9
MD
780 break;
781 case HAMMER2_BREF_TYPE_VOLUME:
5c23d7f1
MD
782 base = &hmp->voldata.sroot_blockset.blockref[0];
783 count = HAMMER2_SET_COUNT;
232a50f9
MD
784 break;
785 default:
5c23d7f1 786 panic("hammer2_chain_push: unrecognized blockref type: %d",
232a50f9 787 parent->bref.type);
5c23d7f1
MD
788 base = NULL; /* safety */
789 count = 0; /* safety */
790 break;
232a50f9 791 }
5c23d7f1 792 KKASSERT(i <= count);
232a50f9 793
5c23d7f1
MD
794 /*
795 * Look for the key. If we are unable to find a match and an exact
796 * match was requested we return NULL. If a range was requested we
797 * run hammer2_chain_next() to iterate.
798 */
799 bref = NULL;
800 while (i < count) {
b7926f31
MD
801 tmp = hammer2_chain_find(hmp, parent, i);
802 bref = (tmp) ? &tmp->bref : &base[i];
c667909f
MD
803 if (bref->type == 0) {
804 ++i;
805 continue;
806 }
e028fa74
MD
807 scan_beg = bref->key;
808 scan_end = scan_beg + ((hammer2_key_t)1 << bref->keybits) - 1;
809 if (key_beg <= scan_end && key_end >= scan_beg)
232a50f9 810 break;
5c23d7f1 811 ++i;
232a50f9 812 }
5c23d7f1
MD
813
814 /*
815 * If we couldn't find a match recurse up a parent to continue the
816 * search.
817 */
818 if (i == count)
819 goto again;
820
821 /*
822 * Acquire the new chain element. If the chain element is an
823 * indirect block we must search recursively.
824 */
c667909f 825 chain = hammer2_chain_get(hmp, parent, i, flags);
5c23d7f1
MD
826 if (chain == NULL)
827 return (NULL);
828
829 /*
830 * If the chain element is an indirect block it becomes the new
831 * parent and we loop on it.
832 */
833 if (chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT) {
834 hammer2_chain_put(hmp, parent);
835 *parentp = parent = chain;
836 i = 0;
837 goto again2;
838 }
839
840 /*
841 * All done, return chain
842 */
232a50f9 843 return (chain);
7cfa8da5
MD
844}
845
846/*
5c23d7f1 847 * Create and return a new hammer2 system memory structure of the specified
37aa19df
MD
848 * key, type and size and insert it RELATIVE TO (PARENT).
849 *
850 * (parent) is typically either an inode or an indirect block, acquired
851 * acquired as a side effect of issuing a prior failed lookup. parent
852 * must be locked and held. Do not pass the inode chain to this function
853 * unless that is the chain returned by the failed lookup.
5c23d7f1
MD
854 *
855 * Non-indirect types will automatically allocate indirect blocks as required
856 * if the new item does not fit in the current (parent).
857 *
858 * Indirect types will move a portion of the existing blockref array in
859 * (parent) into the new indirect type and then use one of the free slots
860 * to emplace the new indirect type.
861 *
862 * A new locked, referenced chain element is returned of the specified type.
db71f61f
MD
863 * This element will also be marked as modified and contain a data area
864 * ready for initialization.
7cfa8da5
MD
865 */
866hammer2_chain_t *
5c23d7f1
MD
867hammer2_chain_create(hammer2_mount_t *hmp, hammer2_chain_t *parent,
868 hammer2_key_t key, int keybits, int type, size_t bytes)
7cfa8da5 869{
5c23d7f1
MD
870 hammer2_blockref_t dummy;
871 hammer2_blockref_t *base;
232a50f9 872 hammer2_blockref_t *bref;
5c23d7f1 873 hammer2_chain_t *chain;
b7926f31 874 hammer2_chain_t dummy_chain;
5c23d7f1 875 int count;
232a50f9 876 int i;
995e78dc 877 int unlock_parent = 0;
232a50f9 878
5c23d7f1
MD
879 /*
880 * First allocate media space and construct the dummy bref, then
881 * allocate the in-memory chain structure.
882 */
883 bzero(&dummy, sizeof(dummy));
884 dummy.type = type;
885 dummy.key = key;
886 dummy.keybits = keybits;
c667909f 887 dummy.data_off = (hammer2_off_t)hammer2_freemap_bytes_to_radix(bytes);
5c23d7f1 888 chain = hammer2_chain_alloc(hmp, &dummy);
232a50f9
MD
889
890 /*
5c23d7f1
MD
891 * Recalculate bytes to reflect the actual media block allocation,
892 * then allocate the local memory copy. This is a new structure
893 * so no I/O is performed.
232a50f9 894 */
5c23d7f1
MD
895 bytes = (hammer2_off_t)1 <<
896 (int)(chain->bref.data_off & HAMMER2_OFF_MASK_RADIX);
db71f61f 897
5c23d7f1 898 switch(type) {
db71f61f
MD
899 case HAMMER2_BREF_TYPE_VOLUME:
900 panic("hammer2_chain_create: called with volume type");
901 break;
5c23d7f1
MD
902 case HAMMER2_BREF_TYPE_INODE:
903 KKASSERT(bytes == HAMMER2_INODE_BYTES);
904 chain->data = (void *)&chain->u.ip->ip_data;
905 break;
906 default:
db71f61f
MD
907 /* leave chain->data NULL */
908 KKASSERT(chain->data == NULL);
5c23d7f1
MD
909 break;
910 }
b7926f31 911 atomic_set_int(&chain->flags, HAMMER2_CHAIN_INITIAL);
5c23d7f1 912
995e78dc 913again:
5c23d7f1
MD
914 /*
915 * Locate a free blockref in the parent's array
916 */
232a50f9
MD
917 switch(parent->bref.type) {
918 case HAMMER2_BREF_TYPE_INODE:
995e78dc 919 KKASSERT(parent->data != NULL);
5c23d7f1
MD
920 base = &parent->data->ipdata.u.blockset.blockref[0];
921 count = HAMMER2_SET_COUNT;
232a50f9
MD
922 break;
923 case HAMMER2_BREF_TYPE_INDIRECT:
995e78dc 924 KKASSERT(parent->data != NULL);
5c23d7f1
MD
925 base = &parent->data->npdata.blockref[0];
926 count = HAMMER2_IND_COUNT;
232a50f9
MD
927 break;
928 case HAMMER2_BREF_TYPE_VOLUME:
995e78dc 929 KKASSERT(parent->data != NULL);
5c23d7f1
MD
930 base = &hmp->voldata.sroot_blockset.blockref[0];
931 count = HAMMER2_SET_COUNT;
232a50f9
MD
932 break;
933 default:
5c23d7f1 934 panic("hammer2_chain_push: unrecognized blockref type: %d",
232a50f9 935 parent->bref.type);
5c23d7f1
MD
936 count = 0;
937 break;
232a50f9
MD
938 }
939
b7926f31 940 /*
db71f61f
MD
941 * Scan for an unallocated bref, also skipping any slots occupied
942 * by in-memory chain elements that may not yet have been updated
943 * in the parent's bref array.
b7926f31
MD
944 */
945 bzero(&dummy_chain, sizeof(dummy_chain));
5c23d7f1
MD
946 bref = NULL;
947 for (i = 0; i < count; ++i) {
948 bref = &base[i];
b7926f31
MD
949 dummy_chain.index = i;
950 if (bref->type == 0 &&
951 SPLAY_FIND(hammer2_chain_splay,
952 &parent->shead, &dummy_chain) == NULL) {
232a50f9 953 break;
b7926f31 954 }
232a50f9 955 }
5c23d7f1
MD
956
957 /*
995e78dc
MD
958 * If no free blockref count be found we must create an indirect
959 * block and move a number of blockrefs into it. With the parent
960 * locked we can safely lock each child in order to move it without
961 * causing a deadlock.
962 *
963 * This may return the new indirect block or the old parent depending
964 * on where the key falls.
5c23d7f1
MD
965 */
966 if (i == count) {
995e78dc
MD
967 hammer2_chain_t *nparent;
968
969 nparent = hammer2_chain_create_indirect(hmp, parent,
970 key, keybits);
971 if (nparent == NULL) {
972 hammer2_chain_free(hmp, chain);
973 chain = NULL;
974 goto done;
975 }
976 if (parent != nparent) {
977 if (unlock_parent)
978 hammer2_chain_put(hmp, parent);
979 parent = nparent;
980 unlock_parent = 1;
981 }
982 goto again;
5c23d7f1
MD
983 }
984
985 /*
b7926f31 986 * Link the chain into its parent.
5c23d7f1
MD
987 */
988 chain->parent = parent;
989 chain->index = i;
990 if (SPLAY_INSERT(hammer2_chain_splay, &parent->shead, chain))
991 panic("hammer2_chain_link: collision");
992 KKASSERT(parent->refs > 1);
993 atomic_add_int(&parent->refs, 1);
e028fa74
MD
994
995 /*
996 * Additional linkage for inodes. Reuse the parent pointer to
997 * find the parent directory.
998 */
b7926f31 999 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) {
995e78dc
MD
1000 hammer2_chain_t *scan = parent;
1001 while (scan->bref.type == HAMMER2_BREF_TYPE_INDIRECT)
1002 scan = scan->parent;
1003 if (scan->bref.type == HAMMER2_BREF_TYPE_INODE)
1004 chain->u.ip->pip = scan->u.ip;
e028fa74 1005 }
5c23d7f1 1006
37494cab 1007 /*
db71f61f
MD
1008 * Mark the newly created chain element as modified and fully
1009 * resolve the chain->data pointer.
1010 *
1011 * Chain elements with embedded data will not issue I/O at this time.
1012 * A new block will be allocated for the buffer but not instantiated.
1013 *
1014 * Chain elements which do not use embedded data will allocate
1015 * the new block AND instantiate its buffer cache buffer, pointing
1016 * the data at the bp.
37494cab
MD
1017 */
1018 hammer2_chain_modify(hmp, chain);
1019
995e78dc
MD
1020done:
1021 if (unlock_parent)
1022 hammer2_chain_put(hmp, parent);
232a50f9 1023 return (chain);
7cfa8da5 1024}
5c23d7f1
MD
1025
1026/*
995e78dc
MD
1027 * Create an indirect block that covers one or more of the elements in the
1028 * current parent. Either returns the existing parent with no locking or
1029 * ref changes or returns the new indirect block locked and referenced,
1030 * depending on what the specified key falls into.
1031 *
1032 * The key/keybits for the indirect mode only needs to follow three rules:
1033 *
1034 * (1) That all elements underneath it fit within its key space and
1035 *
1036 * (2) That all elements outside it are outside its key space.
1037 *
1038 * (3) When creating the new indirect block any elements in the current
1039 * parent that fit within the new indirect block's keyspace must be
1040 * moved into the new indirect block.
1041 *
1042 * (4) The keyspace chosen for the inserted indirect block CAN cover a wider
1043 * keyspace the the current parent, but lookup/iteration rules will
1044 * ensure (and must ensure) that rule (2) for all parents leading up
1045 * to the nearest inode or the root volume header is adhered to. This
1046 * is accomplished by always recursing through matching keyspaces in
1047 * the hammer2_chain_lookup() and hammer2_chain_next() API.
1048 *
1049 * The current implementation calculates the current worst-case keyspace by
1050 * iterating the current parent and then divides it into two halves, choosing
1051 * whichever half has the most elements (not necessarily the half containing
1052 * the requested key).
1053 *
1054 * We can also opt to use the half with the least number of elements. This
1055 * causes lower-numbered keys (aka logical file offsets) to recurse through
1056 * fewer indirect blocks and higher-numbered keys to recurse through more.
1057 * This also has the risk of not moving enough elements to the new indirect
1058 * block and being forced to create several indirect blocks before the element
1059 * can be inserted.
1060 */
1061static
1062hammer2_chain_t *
1063hammer2_chain_create_indirect(hammer2_mount_t *hmp, hammer2_chain_t *parent,
1064 hammer2_key_t create_key, int create_bits)
1065{
1066 hammer2_blockref_t *base;
1067 hammer2_blockref_t *bref;
1068 hammer2_chain_t *chain;
1069 hammer2_chain_t *ichain;
1070 hammer2_chain_t dummy;
1071 hammer2_key_t key = create_key;
1072 int keybits = create_bits;
1073 int locount = 0;
1074 int hicount = 0;
1075 int count;
1076 int i;
1077
995e78dc
MD
1078 /*
1079 * Mark the parent modified so our base[] pointer remains valid
1080 * while we move entries.
1081 */
1082 hammer2_chain_modify(hmp, parent);
1083
1084 /*
1085 * Locate a free blockref in the parent's array
1086 */
1087 switch(parent->bref.type) {
1088 case HAMMER2_BREF_TYPE_INODE:
1089 base = &parent->data->ipdata.u.blockset.blockref[0];
1090 count = HAMMER2_SET_COUNT;
1091 break;
1092 case HAMMER2_BREF_TYPE_INDIRECT:
1093 base = &parent->data->npdata.blockref[0];
1094 count = HAMMER2_IND_COUNT;
1095 break;
1096 case HAMMER2_BREF_TYPE_VOLUME:
1097 base = &hmp->voldata.sroot_blockset.blockref[0];
1098 count = HAMMER2_SET_COUNT;
1099 break;
1100 default:
1101 panic("hammer2_chain_push: unrecognized blockref type: %d",
1102 parent->bref.type);
1103 count = 0;
1104 break;
1105 }
1106
1107 /*
1108 * Scan for an unallocated bref, also skipping any slots occupied
1109 * by in-memory chain elements that may not yet have been updated
1110 * in the parent's bref array.
1111 */
1112 bzero(&dummy, sizeof(dummy));
1113 for (i = 0; i < count; ++i) {
1114 int nkeybits;
1115
1116 bref = &base[i];
1117 if (bref->type == 0) {
1118 dummy.index = i;
1119 chain = SPLAY_FIND(hammer2_chain_splay, &parent->shead,
1120 &dummy);
1121 if (chain == NULL)
1122 continue;
1123 bref = &chain->bref;
1124 }
1125
1126 /*
37aa19df
MD
1127 * Expand our calculated key range (key, keybits) to fit
1128 * the scanned key. nkeybits represents the full range
1129 * that we will later cut in half (two halves @ nkeybits - 1).
995e78dc
MD
1130 */
1131 nkeybits = keybits;
1132 if (nkeybits < bref->keybits)
1133 nkeybits = bref->keybits;
1134 while ((~(((hammer2_key_t)1 << nkeybits) - 1) &
1135 (key ^ bref->key)) != 0) {
1136 ++nkeybits;
1137 }
1138
1139 /*
1140 * If the new key range is larger we have to determine
1141 * which side of the new key range the existing keys fall
1142 * under by checking the high bit, then collapsing the
1143 * locount into the hicount or vise-versa.
1144 */
1145 if (keybits != nkeybits) {
1146 if (((hammer2_key_t)1 << (nkeybits - 1)) & key) {
1147 hicount += locount;
1148 locount = 0;
1149 } else {
1150 locount += hicount;
1151 hicount = 0;
1152 }
1153 keybits = nkeybits;
1154 }
1155
1156 /*
1157 * The newly scanned key will be in the lower half or the
1158 * higher half of the (new) key range.
1159 */
1160 if (((hammer2_key_t)1 << (nkeybits - 1)) & bref->key)
1161 ++hicount;
1162 else
1163 ++locount;
995e78dc
MD
1164 }
1165
1166 /*
37aa19df
MD
1167 * Adjust keybits to represent half of the full range calculated
1168 * above.
1169 */
1170 --keybits;
1171
1172 /*
1173 * Select whichever half contains the most elements. Theoretically
1174 * we can select either side as long as it contains at least one
1175 * element (in order to ensure that a free slot is present to hold
1176 * the indirect block).
995e78dc
MD
1177 */
1178 key &= ~(((hammer2_key_t)1 << keybits) - 1);
1179 if (hammer2_indirect_optimize) {
1180 /*
37aa19df
MD
1181 * Insert node for least number of keys, this will arrange
1182 * the first few blocks of a large file or the first few
1183 * inodes in a directory with fewer indirect blocks when
1184 * created linearly.
995e78dc 1185 */
37aa19df
MD
1186 if (hicount < locount && hicount != 0)
1187 key |= (hammer2_key_t)1 << keybits;
1188 else
1189 key &= ~(hammer2_key_t)1 << keybits;
995e78dc
MD
1190 } else {
1191 /*
1192 * Insert node for most number of keys, best for heavily
1193 * fragmented files.
1194 */
1195 if (hicount > locount)
37aa19df
MD
1196 key |= (hammer2_key_t)1 << keybits;
1197 else
1198 key &= ~(hammer2_key_t)1 << keybits;
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MD
1199 }
1200
1201 /*
1202 * Ok, create our new indirect block
1203 */
1204 dummy.bref.type = HAMMER2_BREF_TYPE_INDIRECT;
1205 dummy.bref.key = key;
37aa19df 1206 dummy.bref.keybits = keybits;
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MD
1207 dummy.bref.data_off = (hammer2_off_t)
1208 hammer2_freemap_bytes_to_radix(HAMMER2_PBUFSIZE);
995e78dc 1209 ichain = hammer2_chain_alloc(hmp, &dummy.bref);
995e78dc
MD
1210
1211 /*
1212 * Iterate the original parent and move the matching brefs into
37aa19df 1213 * the new indirect block.
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MD
1214 */
1215 for (i = 0; i < count; ++i) {
37aa19df
MD
1216 /*
1217 * For keying purposes access the bref from the media or
1218 * from our in-memory cache. In cases where the in-memory
1219 * cache overrides the media the keyrefs will be the same
1220 * anyway so we can avoid checking the cache when the media
1221 * has a key.
1222 */
995e78dc
MD
1223 bref = &base[i];
1224 if (bref->type == 0) {
1225 dummy.index = i;
1226 chain = SPLAY_FIND(hammer2_chain_splay, &parent->shead,
1227 &dummy);
1228 if (chain == NULL) {
1229 /*
1230 * Select index indirect block is placed in
1231 */
1232 if (ichain->index < 0)
1233 ichain->index = i;
1234 continue;
1235 }
995e78dc
MD
1236 bref = &chain->bref;
1237 }
1238
1239 /*
1240 * Skip keys not in the chosen half (low or high), only bit
1241 * (keybits - 1) needs to be compared but for safety we
1242 * will compare all msb bits plus that bit again.
1243 */
37aa19df 1244 if ((~(((hammer2_key_t)1 << keybits) - 1) &
995e78dc
MD
1245 (key ^ bref->key)) != 0) {
1246 continue;
1247 }
1248
1249 /*
1250 * This element is being moved, its slot is available
1251 * for our indirect block.
1252 */
995e78dc
MD
1253 if (ichain->index < 0)
1254 ichain->index = i;
995e78dc
MD
1255
1256 /*
1257 * Load the new indirect block by acquiring or allocating
1258 * the related chain entries, then simply move it to the
1259 * new parent (ichain).
1260 *
1261 * Flagging the new chain entry MOVED will cause a flush
1262 * to synchronize its block into the new indirect block.
5b4a2132
MD
1263 * The chain is unlocked after being moved but needs to
1264 * retain a reference for the MOVED state
1265 *
1266 * We must still set SUBMODIFIED in the parent but we do
1267 * that after the loop.
1268 *
1269 * XXX we really need a lock here but we don't need the
1270 * data. NODATA feature needed.
995e78dc
MD
1271 */
1272 chain = hammer2_chain_get(hmp, parent, i,
1273 HAMMER2_LOOKUP_NOLOCK);
1274 SPLAY_REMOVE(hammer2_chain_splay, &parent->shead, chain);
1275 if (SPLAY_INSERT(hammer2_chain_splay, &ichain->shead, chain))
1276 panic("hammer2_chain_create_indirect: collision");
1277 chain->parent = ichain;
37aa19df 1278 bzero(&base[i], sizeof(base[i]));
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MD
1279 atomic_add_int(&parent->refs, -1);
1280 atomic_add_int(&ichain->refs, 1);
5b4a2132
MD
1281 if (chain->flags & HAMMER2_CHAIN_MOVED) {
1282 hammer2_chain_drop(hmp, chain);
1283 } else {
1284 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MOVED);
1285 }
995e78dc
MD
1286 KKASSERT(parent->refs > 0);
1287 chain = NULL;
1288 }
1289
1290 /*
1291 * Insert the new indirect block into the parent now that we've
1292 * cleared out some entries in the parent. We calculated a good
1293 * insertion index in the loop above (ichain->index).
1294 */
1295 KKASSERT(ichain->index >= 0);
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MD
1296 if (SPLAY_INSERT(hammer2_chain_splay, &parent->shead, ichain))
1297 panic("hammer2_chain_create_indirect: ichain insertion");
1298 ichain->parent = parent;
1299 atomic_add_int(&parent->refs, 1);
1300
1301 /*
1302 * Mark the new indirect block modified after insertion, which
1303 * will propagate up through parent all the way to the root and
1304 * also allocate the physical block in ichain for our caller.
1305 *
1306 * We have to set SUBMODIFIED in ichain's flags manually so the
1307 * flusher knows it has to recurse through it to get to all of
1308 * our moved blocks.
1309 */
1310 hammer2_chain_modify(hmp, ichain);
1311 atomic_set_int(&ichain->flags, HAMMER2_CHAIN_SUBMODIFIED);
1312
1313 /*
1314 * Figure out what to return.
1315 */
1316 if (create_bits >= keybits) {
1317 /*
1318 * Key being created is way outside the key range,
1319 * return the original parent.
1320 */
1321 hammer2_chain_put(hmp, ichain);
37aa19df 1322 } else if (~(((hammer2_key_t)1 << keybits) - 1) &
995e78dc
MD
1323 (create_key ^ key)) {
1324 /*
1325 * Key being created is outside the key range,
1326 * return the original parent.
1327 */
1328 hammer2_chain_put(hmp, ichain);
1329 } else {
1330 /*
1331 * Otherwise its in the range, return the new parent.
1332 */
1333 parent = ichain;
1334 }
1335
995e78dc
MD
1336 return(parent);
1337}
1338
1339/*
5c23d7f1
MD
1340 * Physically delete the specified chain element. Note that inodes with
1341 * open descriptors should not be deleted (as with other filesystems) until
1342 * the last open descriptor is closed.
1343 *
1344 * This routine will remove the chain element from its parent and potentially
1345 * also recurse upward and delete indirect blocks which become empty as a
1346 * side effect.
1347 *
1348 * The caller must pass a pointer to the chain's parent, also locked and
1349 * referenced. (*parentp) will be modified in a manner similar to a lookup
1350 * or iteration when indirect blocks are also deleted as a side effect.
1351 */
1352void
1353hammer2_chain_delete(hammer2_mount_t *hmp, hammer2_chain_t **parentp,
1354 hammer2_chain_t *chain)
1355{
1356}
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MD
1357
1358/*
1359 * Recursively flush the specified chain. The chain is locked and
1360 * referenced by the caller and will remain so on return.
1361 *
1362 * This cannot be called with the volume header's vchain
1363 */
1364void
1365hammer2_chain_flush(hammer2_mount_t *hmp, hammer2_chain_t *chain,
1366 hammer2_blockref_t *parent_bref)
1367{
b7926f31
MD
1368 /*
1369 * Flush any children of this chain entry.
1370 */
1371 if (chain->flags & HAMMER2_CHAIN_SUBMODIFIED) {
1372 hammer2_blockref_t *base;
1373 hammer2_blockref_t bref;
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MD
1374 hammer2_chain_t *scan;
1375 hammer2_chain_t *next;
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MD
1376 int count;
1377 int submodified = 0;
1378
1379 /*
1380 * Modifications to the children will propagate up, forcing
1381 * us to become modified and copy-on-write too.
1382 */
1383 hammer2_chain_modify(hmp, chain);
1384
1385 /*
1386 * The blockref in the parent's array must be repointed at
1387 * the new block allocated by the child after its flush.
1388 *
1389 * Calculate the base of the array.
1390 */
1391 switch(chain->bref.type) {
1392 case HAMMER2_BREF_TYPE_INODE:
1393 KKASSERT(index >= 0 && index < HAMMER2_SET_COUNT);
1394 base = &chain->data->ipdata.u.blockset.blockref[0];
1395 count = HAMMER2_SET_COUNT;
1396 break;
1397 case HAMMER2_BREF_TYPE_INDIRECT:
1398 base = &chain->data->npdata.blockref[0];
1399 count = HAMMER2_IND_COUNT;
1400 break;
1401 case HAMMER2_BREF_TYPE_VOLUME:
1402 KKASSERT(index >= 0 && index < HAMMER2_SET_COUNT);
1403 base = &hmp->voldata.sroot_blockset.blockref[0];
1404 count = HAMMER2_SET_COUNT;
1405 break;
1406 default:
1407 base = NULL;
1408 panic("hammer2_chain_get: unrecognized blockref type: %d",
1409 chain->bref.type);
1410 }
1411
1412 /*
c667909f
MD
1413 * Flush the children and update the blockrefs in the parent.
1414 * Be careful of ripouts during the loop.
b7926f31 1415 */
c667909f
MD
1416 next = SPLAY_MIN(hammer2_chain_splay, &chain->shead);
1417 while ((scan = next) != NULL) {
1418 next = SPLAY_NEXT(hammer2_chain_splay, &chain->shead,
1419 scan);
b7926f31 1420 if (scan->flags & (HAMMER2_CHAIN_SUBMODIFIED |
995e78dc
MD
1421 HAMMER2_CHAIN_MODIFIED |
1422 HAMMER2_CHAIN_MOVED)) {
b7926f31
MD
1423 hammer2_chain_ref(hmp, scan);
1424 hammer2_chain_lock(hmp, scan);
1425 bref = base[scan->index];
1426 hammer2_chain_flush(hmp, scan, &bref);
1427 if (scan->flags & (HAMMER2_CHAIN_SUBMODIFIED |
1428 HAMMER2_CHAIN_MODIFIED)) {
1429 submodified = 1;
1430 kprintf("flush race, sub dirty\n");
1431 } else {
1432 KKASSERT(scan->index < count);
1433 base[scan->index] = bref;
5b4a2132
MD
1434 if (scan->flags & HAMMER2_CHAIN_MOVED) {
1435 atomic_clear_int(&scan->flags,
995e78dc 1436 HAMMER2_CHAIN_MOVED);
5b4a2132
MD
1437 hammer2_chain_drop(hmp, scan);
1438 }
b7926f31
MD
1439 }
1440 hammer2_chain_put(hmp, scan);
1441 }
1442 }
1443 if (submodified == 0) {
1444 atomic_clear_int(&chain->flags,
1445 HAMMER2_CHAIN_SUBMODIFIED);
1446 }
1447 }
1448
1449 /*
db71f61f 1450 * Flush this chain entry only if it is marked modified.
995e78dc
MD
1451 *
1452 * If the chain entry was moved we must still updated *parent_bref
1453 * or the indirect block won't be adjusted to point to us.
b7926f31 1454 */
995e78dc
MD
1455 if ((chain->flags & HAMMER2_CHAIN_MODIFIED) == 0) {
1456 if (chain->flags & HAMMER2_CHAIN_MOVED)
1457 *parent_bref = chain->bref;
b7926f31 1458 return;
995e78dc 1459 }
b7926f31
MD
1460
1461 /*
1462 * If this is part of a recursive flush we can go ahead and write
1463 * out the buffer cache buffer and pass a new bref back up the chain.
1464 *
1465 * This will never be a volume header.
1466 */
1467 if (parent_bref) {
1468 hammer2_blockref_t *bref;
1469 hammer2_off_t off_hi;
db71f61f 1470 struct buf *bp;
b7926f31
MD
1471 size_t off_lo;
1472 size_t bytes;
1473 int error;
b7926f31
MD
1474
1475 KKASSERT(chain->data != NULL);
b7926f31
MD
1476 bref = &chain->bref;
1477
1478 off_hi = bref->data_off & HAMMER2_OFF_MASK_HI;
1479 off_lo = (size_t)bref->data_off & HAMMER2_OFF_MASK_LO;
1480 bytes = 1 << (int)(bref->data_off & HAMMER2_OFF_MASK_RADIX);
1481 KKASSERT(off_hi != 0); /* not the root volume header */
db71f61f
MD
1482
1483 if (chain->bp) {
1484 /*
c667909f
MD
1485 * The data is mapped directly to the bp and will be
1486 * written out when the chain is unlocked by the
1487 * parent. However, since we are clearing the
1488 * MODIFIED flag we have to set the FLUSHED flag
1489 * so the hammer2_chain_unlock() code knows to
1490 * bdwrite() the buffer.
db71f61f 1491 */
c667909f 1492 atomic_set_int(&chain->flags, HAMMER2_CHAIN_FLUSHED);
db71f61f
MD
1493 } else {
1494 /*
1495 * The data is embedded, we have to acquire the
1496 * buffer cache buffer and copy the data into it.
1497 */
1498 bp = NULL;
1499 error = bread(hmp->devvp, off_hi,
1500 HAMMER2_PBUFSIZE, &bp);
1501 KKASSERT(error == 0); /* XXX */
1502
b7926f31
MD
1503 /*
1504 * Copy the data to the buffer, mark the buffer
1505 * dirty, and convert the chain to unmodified.
b7926f31 1506 */
db71f61f
MD
1507 bcopy(chain->data, (char *)bp->b_data + off_lo, bytes);
1508 bdwrite(bp);
1509 bp = NULL;
1510
b7926f31
MD
1511 chain->bref.check.iscsi32.value =
1512 hammer2_icrc32(chain->data, bytes);
b7926f31 1513 }
c667909f
MD
1514
1515 /*
1516 * Return information on the new block to the parent.
1517 */
1518 *parent_bref = chain->bref;
1519 hammer2_chain_drop(hmp, chain); /* drop ref tracking mod bit */
db71f61f 1520 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_MODIFIED);
b7926f31
MD
1521 } else {
1522 hammer2_blockref_t *bref;
1523
1524 KKASSERT(chain->data != NULL);
1525 KKASSERT(chain->bp == NULL);
1526 bref = &chain->bref;
1527
1528 switch(bref->type) {
1529 case HAMMER2_BREF_TYPE_VOLUME:
1530 hmp->voldata.icrc_sects[HAMMER2_VOL_ICRC_SECT1]=
1531 hammer2_icrc32(
1532 (char *)&hmp->voldata +
1533 HAMMER2_VOLUME_ICRC1_OFF,
1534 HAMMER2_VOLUME_ICRC1_SIZE);
1535 hmp->voldata.icrc_sects[HAMMER2_VOL_ICRC_SECT0]=
1536 hammer2_icrc32(
1537 (char *)&hmp->voldata +
1538 HAMMER2_VOLUME_ICRC0_OFF,
1539 HAMMER2_VOLUME_ICRC0_SIZE);
1540 hmp->voldata.icrc_volheader =
1541 hammer2_icrc32(
1542 (char *)&hmp->voldata +
1543 HAMMER2_VOLUME_ICRCVH_OFF,
1544 HAMMER2_VOLUME_ICRCVH_SIZE);
1545 break;
1546 }
1547 }
1548}