xref: /dflybsd-src/sys/vfs/hammer2/hammer2_subr.c (revision 3170ffd7ca62e2b163aac1bff57a8d23461a7974)
1 /*
2  * Copyright (c) 2011-2013 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  */
35 #include <sys/cdefs.h>
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/types.h>
39 #include <sys/lock.h>
40 #include <sys/uuid.h>
41 #include <sys/dirent.h>
42 
43 #include "hammer2.h"
44 
45 /*
46  * HAMMER2 inode locks
47  *
48  * HAMMER2 offers shared locks and exclusive locks on inodes.
49  *
50  * An inode's ip->chain pointer is resolved and stable while an inode is
51  * locked, and can be cleaned out at any time (become NULL) when an inode
52  * is not locked.
53  *
54  * The underlying chain is also locked and returned.
55  *
56  * NOTE: We don't combine the inode/chain lock because putting away an
57  *       inode would otherwise confuse multiple lock holders of the inode.
58  */
59 void
60 hammer2_inode_lock_ex(hammer2_inode_t *ip)
61 {
62 	hammer2_chain_t *chain;
63 
64 	hammer2_inode_ref(ip);
65 	ccms_thread_lock(&ip->topo_cst, CCMS_STATE_EXCLUSIVE);
66 
67 	/*
68 	 * ip->chain fixup.  Certain duplications used to move inodes
69 	 * into indirect blocks (for example) can cause ip->chain to
70 	 * become stale.
71 	 *
72 	 *
73 	 */
74 again:
75 	chain = ip->chain;
76 	while (chain->duplink && (chain->flags & HAMMER2_CHAIN_DELETED))
77 		chain = chain->duplink;
78 	if (chain != ip->chain) {
79 		hammer2_chain_ref(chain);
80 		hammer2_chain_drop(ip->chain);
81 		ip->chain = chain;
82 	}
83 
84 	KKASSERT(chain != NULL);	/* for now */
85 	hammer2_chain_lock(chain, HAMMER2_RESOLVE_ALWAYS);
86 
87 	/*
88 	 * Resolve duplication races
89 	 */
90 	if (chain->duplink && (chain->flags & HAMMER2_CHAIN_DELETED)) {
91 		hammer2_chain_unlock(chain);
92 		goto again;
93 	}
94 }
95 
96 void
97 hammer2_inode_unlock_ex(hammer2_inode_t *ip)
98 {
99 	hammer2_chain_t *chain;
100 
101 	/*
102 	 * XXX this will catch parent directories too which we don't
103 	 *     really want.
104 	 */
105 	chain = ip->chain;
106 	if (chain) {
107 		if (chain->flags & (HAMMER2_CHAIN_MODIFIED |
108 				    HAMMER2_CHAIN_SUBMODIFIED)) {
109 			atomic_set_int(&ip->flags, HAMMER2_INODE_MODIFIED);
110 		}
111 		hammer2_chain_unlock(chain);
112 	}
113 	ccms_thread_unlock(&ip->topo_cst);
114 	hammer2_inode_drop(ip);
115 }
116 
117 /*
118  * NOTE: We don't combine the inode/chain lock because putting away an
119  *       inode would otherwise confuse multiple lock holders of the inode.
120  *
121  *	 Shared locks are especially sensitive to having too many shared
122  *	 lock counts (from the same thread) on certain paths which might
123  *	 need to upgrade them.  Only one count of a shared lock can be
124  *	 upgraded.
125  */
126 void
127 hammer2_inode_lock_sh(hammer2_inode_t *ip)
128 {
129 	hammer2_chain_t *chain;
130 
131 	hammer2_inode_ref(ip);
132 again:
133 	ccms_thread_lock(&ip->topo_cst, CCMS_STATE_SHARED);
134 
135 	chain = ip->chain;
136 	KKASSERT(chain != NULL);	/* for now */
137 	hammer2_chain_lock(chain, HAMMER2_RESOLVE_ALWAYS |
138 				  HAMMER2_RESOLVE_SHARED);
139 
140 	/*
141 	 * Resolve duplication races
142 	 */
143 	if (chain->duplink && (chain->flags & HAMMER2_CHAIN_DELETED)) {
144 		hammer2_chain_unlock(chain);
145 		ccms_thread_unlock(&ip->topo_cst);
146 		hammer2_inode_lock_ex(ip);
147 		hammer2_inode_unlock_ex(ip);
148 		goto again;
149 	}
150 
151 }
152 
153 void
154 hammer2_inode_unlock_sh(hammer2_inode_t *ip)
155 {
156 	if (ip->chain)
157 		hammer2_chain_unlock(ip->chain);
158 	ccms_thread_unlock(&ip->topo_cst);
159 	hammer2_inode_drop(ip);
160 }
161 
162 ccms_state_t
163 hammer2_inode_lock_temp_release(hammer2_inode_t *ip)
164 {
165 	return(ccms_thread_lock_temp_release(&ip->topo_cst));
166 }
167 
168 void
169 hammer2_inode_lock_temp_restore(hammer2_inode_t *ip, ccms_state_t ostate)
170 {
171 	ccms_thread_lock_temp_restore(&ip->topo_cst, ostate);
172 }
173 
174 ccms_state_t
175 hammer2_inode_lock_upgrade(hammer2_inode_t *ip)
176 {
177 	return(ccms_thread_lock_upgrade(&ip->topo_cst));
178 }
179 
180 void
181 hammer2_inode_lock_downgrade(hammer2_inode_t *ip, ccms_state_t ostate)
182 {
183 	ccms_thread_lock_downgrade(&ip->topo_cst, ostate);
184 }
185 
186 /*
187  * Mount-wide locks
188  */
189 
190 void
191 hammer2_mount_exlock(hammer2_mount_t *hmp)
192 {
193 	ccms_thread_lock(&hmp->vchain.core->cst, CCMS_STATE_EXCLUSIVE);
194 }
195 
196 void
197 hammer2_mount_shlock(hammer2_mount_t *hmp)
198 {
199 	ccms_thread_lock(&hmp->vchain.core->cst, CCMS_STATE_SHARED);
200 }
201 
202 void
203 hammer2_mount_unlock(hammer2_mount_t *hmp)
204 {
205 	ccms_thread_unlock(&hmp->vchain.core->cst);
206 }
207 
208 void
209 hammer2_voldata_lock(hammer2_mount_t *hmp)
210 {
211 	lockmgr(&hmp->voldatalk, LK_EXCLUSIVE);
212 }
213 
214 void
215 hammer2_voldata_unlock(hammer2_mount_t *hmp, int modify)
216 {
217 	if (modify &&
218 	    (hmp->vchain.flags & HAMMER2_CHAIN_MODIFIED) == 0) {
219 		atomic_set_int(&hmp->vchain.flags, HAMMER2_CHAIN_MODIFIED);
220 		hammer2_chain_ref(&hmp->vchain);
221 	}
222 	lockmgr(&hmp->voldatalk, LK_RELEASE);
223 }
224 
225 /*
226  * Return the directory entry type for an inode.
227  *
228  * ip must be locked sh/ex.
229  */
230 int
231 hammer2_get_dtype(hammer2_chain_t *chain)
232 {
233 	uint8_t type;
234 
235 	KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_INODE);
236 
237 	if ((type = chain->data->ipdata.type) == HAMMER2_OBJTYPE_HARDLINK)
238 		type = chain->data->ipdata.target_type;
239 
240 	switch(type) {
241 	case HAMMER2_OBJTYPE_UNKNOWN:
242 		return (DT_UNKNOWN);
243 	case HAMMER2_OBJTYPE_DIRECTORY:
244 		return (DT_DIR);
245 	case HAMMER2_OBJTYPE_REGFILE:
246 		return (DT_REG);
247 	case HAMMER2_OBJTYPE_FIFO:
248 		return (DT_FIFO);
249 	case HAMMER2_OBJTYPE_CDEV:	/* not supported */
250 		return (DT_CHR);
251 	case HAMMER2_OBJTYPE_BDEV:	/* not supported */
252 		return (DT_BLK);
253 	case HAMMER2_OBJTYPE_SOFTLINK:
254 		return (DT_LNK);
255 	case HAMMER2_OBJTYPE_HARDLINK:	/* (never directly associated w/vp) */
256 		return (DT_UNKNOWN);
257 	case HAMMER2_OBJTYPE_SOCKET:
258 		return (DT_SOCK);
259 	case HAMMER2_OBJTYPE_WHITEOUT:	/* not supported */
260 		return (DT_UNKNOWN);
261 	default:
262 		return (DT_UNKNOWN);
263 	}
264 	/* not reached */
265 }
266 
267 /*
268  * Return the directory entry type for an inode
269  */
270 int
271 hammer2_get_vtype(hammer2_chain_t *chain)
272 {
273 	KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_INODE);
274 
275 	switch(chain->data->ipdata.type) {
276 	case HAMMER2_OBJTYPE_UNKNOWN:
277 		return (VBAD);
278 	case HAMMER2_OBJTYPE_DIRECTORY:
279 		return (VDIR);
280 	case HAMMER2_OBJTYPE_REGFILE:
281 		return (VREG);
282 	case HAMMER2_OBJTYPE_FIFO:
283 		return (VFIFO);
284 	case HAMMER2_OBJTYPE_CDEV:	/* not supported */
285 		return (VCHR);
286 	case HAMMER2_OBJTYPE_BDEV:	/* not supported */
287 		return (VBLK);
288 	case HAMMER2_OBJTYPE_SOFTLINK:
289 		return (VLNK);
290 	case HAMMER2_OBJTYPE_HARDLINK:	/* XXX */
291 		return (VBAD);
292 	case HAMMER2_OBJTYPE_SOCKET:
293 		return (VSOCK);
294 	case HAMMER2_OBJTYPE_WHITEOUT:	/* not supported */
295 		return (DT_UNKNOWN);
296 	default:
297 		return (DT_UNKNOWN);
298 	}
299 	/* not reached */
300 }
301 
302 u_int8_t
303 hammer2_get_obj_type(enum vtype vtype)
304 {
305 	switch(vtype) {
306 	case VDIR:
307 		return(HAMMER2_OBJTYPE_DIRECTORY);
308 	case VREG:
309 		return(HAMMER2_OBJTYPE_REGFILE);
310 	case VFIFO:
311 		return(HAMMER2_OBJTYPE_FIFO);
312 	case VSOCK:
313 		return(HAMMER2_OBJTYPE_SOCKET);
314 	case VCHR:
315 		return(HAMMER2_OBJTYPE_CDEV);
316 	case VBLK:
317 		return(HAMMER2_OBJTYPE_BDEV);
318 	case VLNK:
319 		return(HAMMER2_OBJTYPE_SOFTLINK);
320 	default:
321 		return(HAMMER2_OBJTYPE_UNKNOWN);
322 	}
323 	/* not reached */
324 }
325 
326 /*
327  * Convert a hammer2 64-bit time to a timespec.
328  */
329 void
330 hammer2_time_to_timespec(u_int64_t xtime, struct timespec *ts)
331 {
332 	ts->tv_sec = (unsigned long)(xtime / 1000000);
333 	ts->tv_nsec = (unsigned int)(xtime % 1000000) * 1000L;
334 }
335 
336 u_int64_t
337 hammer2_timespec_to_time(struct timespec *ts)
338 {
339 	u_int64_t xtime;
340 
341 	xtime = (unsigned)(ts->tv_nsec / 1000) +
342 		(unsigned long)ts->tv_sec * 1000000ULL;
343 	return(xtime);
344 }
345 
346 /*
347  * Convert a uuid to a unix uid or gid
348  */
349 u_int32_t
350 hammer2_to_unix_xid(uuid_t *uuid)
351 {
352 	return(*(u_int32_t *)&uuid->node[2]);
353 }
354 
355 void
356 hammer2_guid_to_uuid(uuid_t *uuid, u_int32_t guid)
357 {
358 	bzero(uuid, sizeof(*uuid));
359 	*(u_int32_t *)&uuid->node[2] = guid;
360 }
361 
362 /*
363  * Borrow HAMMER1's directory hash algorithm #1 with a few modifications.
364  * The filename is split into fields which are hashed separately and then
365  * added together.
366  *
367  * Differences include: bit 63 must be set to 1 for HAMMER2 (HAMMER1 sets
368  * it to 0), this is because bit63=0 is used for hidden hardlinked inodes.
369  * (This means we do not need to do a 0-check/or-with-0x100000000 either).
370  *
371  * Also, the iscsi crc code is used instead of the old crc32 code.
372  */
373 hammer2_key_t
374 hammer2_dirhash(const unsigned char *name, size_t len)
375 {
376 	const unsigned char *aname = name;
377 	uint32_t crcx;
378 	uint64_t key;
379 	size_t i;
380 	size_t j;
381 
382 	key = 0;
383 
384 	/*
385 	 * m32
386 	 */
387 	crcx = 0;
388 	for (i = j = 0; i < len; ++i) {
389 		if (aname[i] == '.' ||
390 		    aname[i] == '-' ||
391 		    aname[i] == '_' ||
392 		    aname[i] == '~') {
393 			if (i != j)
394 				crcx += hammer2_icrc32(aname + j, i - j);
395 			j = i + 1;
396 		}
397 	}
398 	if (i != j)
399 		crcx += hammer2_icrc32(aname + j, i - j);
400 
401 	/*
402 	 * The directory hash utilizes the top 32 bits of the 64-bit key.
403 	 * Bit 63 must be set to 1.
404 	 */
405 	crcx |= 0x80000000U;
406 	key |= (uint64_t)crcx << 32;
407 
408 	/*
409 	 * l16 - crc of entire filename
410 	 *
411 	 * This crc reduces degenerate hash collision conditions
412 	 */
413 	crcx = hammer2_icrc32(aname, len);
414 	crcx = crcx ^ (crcx << 16);
415 	key |= crcx & 0xFFFF0000U;
416 
417 	/*
418 	 * Set bit 15.  This allows readdir to strip bit 63 so a positive
419 	 * 64-bit cookie/offset can always be returned, and still guarantee
420 	 * that the values 0x0000-0x7FFF are available for artificial entries.
421 	 * ('.' and '..').
422 	 */
423 	key |= 0x8000U;
424 
425 	return (key);
426 }
427 
428 /*
429  * Return the power-of-2 radix greater or equal to
430  * the specified number of bytes.
431  *
432  * Always returns at least the minimum media allocation
433  * size radix, HAMMER2_MIN_RADIX (10), which is 1KB.
434  */
435 int
436 hammer2_allocsize(size_t bytes)
437 {
438 	int radix;
439 
440 	if (bytes < HAMMER2_MIN_ALLOC)
441 		bytes = HAMMER2_MIN_ALLOC;
442 	if (bytes == HAMMER2_PBUFSIZE)
443 		radix = HAMMER2_PBUFRADIX;
444 	else if (bytes >= 16384)
445 		radix = 14;
446 	else if (bytes >= 1024)
447 		radix = 10;
448 	else
449 		radix = HAMMER2_MIN_RADIX;
450 
451 	while (((size_t)1 << radix) < bytes)
452 		++radix;
453 	return (radix);
454 }
455 
456 /*
457  * ip must be locked sh/ex
458  */
459 int
460 hammer2_calc_logical(hammer2_inode_t *ip, hammer2_off_t uoff,
461 		     hammer2_key_t *lbasep, hammer2_key_t *leofp)
462 {
463 	hammer2_inode_data_t *ipdata = &ip->chain->data->ipdata;
464 	int radix;
465 
466 	*lbasep = uoff & ~HAMMER2_PBUFMASK64;
467 	*leofp = ipdata->size & ~HAMMER2_PBUFMASK64;
468 	KKASSERT(*lbasep <= *leofp);
469 	if (*lbasep == *leofp /*&& *leofp < 1024 * 1024*/) {
470 		radix = hammer2_allocsize((size_t)(ipdata->size - *leofp));
471 		if (radix < HAMMER2_MINALLOCRADIX)
472 			radix = HAMMER2_MINALLOCRADIX;
473 		*leofp += 1U << radix;
474 		return (1U << radix);
475 	} else {
476 		return (HAMMER2_PBUFSIZE);
477 	}
478 }
479 
480 void
481 hammer2_update_time(uint64_t *timep)
482 {
483 	struct timeval tv;
484 
485 	getmicrotime(&tv);
486 	*timep = (unsigned long)tv.tv_sec * 1000000 + tv.tv_usec;
487 }
488