2 * Copyright (c) 2011-2012 The DragonFly Project. All rights reserved.
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>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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
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.
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
35 #include <sys/cdefs.h>
36 #include <sys/cdefs.h>
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/types.h>
46 * Adding a ref to an inode is only legal if the inode already has at least
50 hammer2_inode_ref(hammer2_inode_t *ip)
52 hammer2_chain_ref(ip->hmp, &ip->chain);
56 * Drop an inode reference, freeing the inode when the last reference goes
60 hammer2_inode_drop(hammer2_inode_t *ip)
62 hammer2_chain_drop(ip->hmp, &ip->chain);
66 * Get the vnode associated with the given inode, allocating the vnode if
69 * Great care must be taken to avoid deadlocks and vnode acquisition/reclaim
72 * The vnode will be returned exclusively locked and referenced. The
73 * reference on the vnode prevents it from being reclaimed.
75 * The inode (ip) must be referenced by the caller and not locked to avoid
76 * it getting ripped out from under us or deadlocked.
79 hammer2_igetv(hammer2_inode_t *ip, int *errorp)
89 * Attempt to reuse an existing vnode assignment. It is
90 * possible to race a reclaim so the vget() may fail. The
91 * inode must be unlocked during the vget() to avoid a
92 * deadlock against a reclaim.
97 * Lock the inode and check for a reclaim race
99 hammer2_inode_lock_ex(ip);
101 hammer2_inode_unlock_ex(ip);
106 * Inode must be unlocked during the vget() to avoid
107 * possible deadlocks, vnode is held to prevent
108 * destruction during the vget(). The vget() can
109 * still fail if we lost a reclaim race on the vnode.
111 vhold_interlocked(vp);
112 hammer2_inode_unlock_ex(ip);
113 if (vget(vp, LK_EXCLUSIVE)) {
118 /* vp still locked and ref from vget */
124 * No vnode exists, allocate a new vnode. Beware of
125 * allocation races. This function will return an
126 * exclusively locked and referenced vnode.
128 *errorp = getnewvnode(VT_HAMMER2, H2TOMP(hmp), &vp, 0, 0);
135 * Lock the inode and check for an allocation race.
137 hammer2_inode_lock_ex(ip);
138 if (ip->vp != NULL) {
141 hammer2_inode_unlock_ex(ip);
145 switch (ip->ip_data.type) {
146 case HAMMER2_OBJTYPE_DIRECTORY:
149 case HAMMER2_OBJTYPE_REGFILE:
151 vinitvmio(vp, ip->ip_data.size,
153 (int)ip->ip_data.size & HAMMER2_LBUFMASK);
155 case HAMMER2_OBJTYPE_SOFTLINK:
157 * XXX for now we are using the generic file_read
158 * and file_write code so we need a buffer cache
162 vinitvmio(vp, ip->ip_data.size,
164 (int)ip->ip_data.size & HAMMER2_LBUFMASK);
168 panic("hammer2: unhandled objtype %d",
173 if (ip == hmp->iroot)
174 vsetflags(vp, VROOT);
178 hammer2_chain_ref(hmp, &ip->chain); /* vp association */
179 hammer2_inode_unlock_ex(ip);
184 * Return non-NULL vp and *errorp == 0, or NULL vp and *errorp != 0.
186 if (hammer2_debug & 0x0002) {
187 kprintf("igetv vp %p refs %d aux %d\n",
188 vp, vp->v_sysref.refcnt, vp->v_auxrefs);
194 * Create a new inode in the specified directory using the vattr to
195 * figure out the type of inode.
197 * If no error occurs the new inode with its chain locked is returned in
198 * *nipp, otherwise an error is returned and *nipp is set to NULL.
201 hammer2_inode_create(hammer2_mount_t *hmp,
202 struct vattr *vap, struct ucred *cred,
203 hammer2_inode_t *dip,
204 const uint8_t *name, size_t name_len,
205 hammer2_inode_t **nipp)
207 hammer2_chain_t *chain;
208 hammer2_chain_t *parent;
209 hammer2_inode_t *nip;
213 lhc = hammer2_dirhash(name, name_len);
216 * Locate the inode or indirect block to create the new
217 * entry in. At the same time check for key collisions
218 * and iterate until we don't get one.
220 parent = &dip->chain;
221 hammer2_chain_ref(hmp, parent);
222 hammer2_chain_lock(hmp, parent);
226 chain = hammer2_chain_lookup(hmp, &parent, lhc, lhc, 0);
229 if ((lhc & HAMMER2_DIRHASH_LOMASK) == HAMMER2_DIRHASH_LOMASK)
231 hammer2_chain_put(hmp, chain);
236 chain = hammer2_chain_create(hmp, parent, NULL, lhc, 0,
237 HAMMER2_BREF_TYPE_INODE,
238 HAMMER2_INODE_BYTES);
242 hammer2_chain_put(hmp, parent);
245 * Handle the error case
248 KKASSERT(chain == NULL);
254 * Set up the new inode
259 nip->ip_data.type = hammer2_get_obj_type(vap->va_type);
260 nip->ip_data.inum = hmp->voldata.alloc_tid++; /* XXX modify/lock */
261 nip->ip_data.version = HAMMER2_INODE_VERSION_ONE;
262 nip->ip_data.ctime = 0;
263 nip->ip_data.mtime = 0;
264 nip->ip_data.mode = vap->va_mode;
265 nip->ip_data.nlinks = 1;
269 * Regular files and softlinks allow a small amount of data to be
270 * directly embedded in the inode. This flag will be cleared if
271 * the size is extended past the embedded limit.
273 if (nip->ip_data.type == HAMMER2_OBJTYPE_REGFILE ||
274 nip->ip_data.type == HAMMER2_OBJTYPE_SOFTLINK) {
275 nip->ip_data.op_flags |= HAMMER2_OPFLAG_DIRECTDATA;
278 KKASSERT(name_len < HAMMER2_INODE_MAXNAME);
279 bcopy(name, nip->ip_data.filename, name_len);
280 nip->ip_data.name_key = lhc;
281 nip->ip_data.name_len = name_len;
287 * Connect inode (ip) to the specified directory using the specified name.
288 * (ip) must be locked.
291 hammer2_inode_connect(hammer2_inode_t *dip, hammer2_inode_t *ip,
292 const uint8_t *name, size_t name_len)
294 hammer2_mount_t *hmp = dip->hmp;
295 hammer2_chain_t *chain;
296 hammer2_chain_t *parent;
300 lhc = hammer2_dirhash(name, name_len);
303 * Locate the inode or indirect block to create the new
304 * entry in. At the same time check for key collisions
305 * and iterate until we don't get one.
307 parent = &dip->chain;
308 hammer2_chain_ref(hmp, parent);
309 hammer2_chain_lock(hmp, parent);
313 chain = hammer2_chain_lookup(hmp, &parent, lhc, lhc, 0);
316 if ((lhc & HAMMER2_DIRHASH_LOMASK) == HAMMER2_DIRHASH_LOMASK)
318 hammer2_chain_put(hmp, chain);
324 * Passing a non-NULL chain to hammer2_chain_create() reconnects the
325 * existing chain instead of creating a new one. The chain's bref
326 * will be properly updated.
329 chain = hammer2_chain_create(hmp, parent, &ip->chain, lhc, 0,
330 HAMMER2_BREF_TYPE_INODE /* n/a */,
331 HAMMER2_INODE_BYTES); /* n/a */
335 hammer2_chain_put(hmp, parent);
338 * Handle the error case
341 KKASSERT(chain == NULL);
346 * Directory entries are inodes so if the name has changed we have
347 * to update the inode.
349 if (ip->ip_data.name_len != name_len ||
350 bcmp(ip->ip_data.filename, name, name_len) != 0) {
351 hammer2_chain_modify(hmp, chain);
352 KKASSERT(name_len < HAMMER2_INODE_MAXNAME);
353 bcopy(name, ip->ip_data.filename, name_len);
354 ip->ip_data.name_key = lhc;
355 ip->ip_data.name_len = name_len;
357 /*nip->ip_data.nlinks = 1;*/
363 * Create a hardlink forwarding entry (dip, name) to the specified (ip).
365 * This is one of the more complex implementations in HAMMER2. The
366 * filesystem strictly updates its chains bottom-up in a copy-on-write
367 * fashion. This makes hardlinks difficult to implement but we've come up
368 * with a dandy solution.
370 * When a file has more than one link the actual inode is created as a
371 * hidden directory entry (indexed by inode number) in a common parent of
372 * all hardlinks which reference the file. The hardlinks in each directory
373 * are merely forwarding entries to the hidden inode.
377 * Most VOPs can be blissfully unaware of the forwarding entries.
378 * nresolve, nlink, and remove code have to be forwarding-aware
379 * in order to return the (ip/vp) for the actual file (and otherwise do
382 * (1) If the ip we are linking to is a normal embedded inode (nlinks==1)
383 * we have to replace the directory entry with a forwarding inode
384 * and move the normal ip/vp to a hidden entry indexed by the inode
385 * number in a common parent directory.
387 * (2) If the ip we are linking to is already a hidden entry but is not
388 * a common parent we have to move its entry to a common parent by
389 * moving the entry upward.
391 * (3) The trivial case is the entry is already hidden and already a
392 * common parent. We adjust nlinks for the entry and are done.
393 * (this is the fall-through case).
396 hammer2_hardlink_create(hammer2_inode_t *ip, hammer2_inode_t *dip,
397 const uint8_t *name, size_t name_len)
401 hammer2_inode_t *nip;
402 hammer2_inode_t *xip;
405 hammer2_inode_t *nip; /* hardlink forwarding inode */
406 error = hammer2_inode_create(hmp, NULL, ap->a_cred,
407 dip, name, name_len, &nip);
409 KKASSERT(nip == NULL);
412 KKASSERT(nip->ip_data.type == HAMMER2_OBJTYPE_HARDLINK);
413 hammer2_chain_modify(&nip->chain);
414 nip->ip_data.inum = ip->ip_data.inum;
415 hammer2_chain_put(hmp, &nip->chain);
421 hammer2_inode_calc_alloc(hammer2_key_t filesize)
423 int frag = (int)filesize & HAMMER2_PBUFMASK;
428 for (radix = HAMMER2_MINIORADIX; frag > (1 << radix); ++radix)