4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License version 2 for more details (a copy is included
14 * in the LICENSE file that accompanied this code).
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
20 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21 * CA 95054 USA or visit www.sun.com if you need additional information or
27 * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
28 * Use is subject to license terms.
30 * Copyright (c) 2011, Whamcloud, Inc.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
38 #include <linux/sched.h>
39 #include <linux/quotaops.h>
41 #define DEBUG_SUBSYSTEM S_LLITE
43 #include <obd_support.h>
44 #include <lustre_lite.h>
45 #include <lustre/lustre_idl.h>
46 #include <lustre_dlm.h>
48 #include "llite_internal.h"
50 static void free_dentry_data(struct rcu_head *head)
52 struct ll_dentry_data *lld;
54 lld = container_of(head, struct ll_dentry_data, lld_rcu_head);
58 /* should NOT be called with the dcache lock, see fs/dcache.c */
59 static void ll_release(struct dentry *de)
61 struct ll_dentry_data *lld;
65 if (lld == NULL) /* NFS copies the de->d_op methods (bug 4655) */
69 ll_intent_release(lld->lld_it);
70 OBD_FREE(lld->lld_it, sizeof(*lld->lld_it));
72 LASSERT(lld->lld_cwd_count == 0);
73 LASSERT(lld->lld_mnt_count == 0);
75 call_rcu(&lld->lld_rcu_head, free_dentry_data);
80 /* Compare if two dentries are the same. Don't match if the existing dentry
81 * is marked invalid. Returns 1 if different, 0 if the same.
83 * This avoids a race where ll_lookup_it() instantiates a dentry, but we get
84 * an AST before calling d_revalidate_it(). The dentry still exists (marked
85 * INVALID) so d_lookup() matches it, but we have no lock on it (so
86 * lock_match() fails) and we spin around real_lookup(). */
87 #ifdef HAVE_D_COMPARE_7ARGS
88 int ll_dcompare(const struct dentry *parent, const struct inode *pinode,
89 const struct dentry *dentry, const struct inode *inode,
90 unsigned int len, const char *str, const struct qstr *name)
92 int ll_dcompare(struct dentry *parent, struct qstr *d_name, struct qstr *name)
95 #ifdef HAVE_D_COMPARE_7ARGS
101 if (memcmp(str, name->name, len))
104 struct dentry *dentry;
107 if (d_name->len != name->len)
110 if (memcmp(d_name->name, name->name, name->len))
113 /* XXX: d_name must be in-dentry structure */
114 dentry = container_of(d_name, struct dentry, d_name); /* ugh */
117 CDEBUG(D_DENTRY, "found name %.*s(%p) flags %#x refc %d\n",
118 name->len, name->name, dentry, dentry->d_flags,
121 /* mountpoint is always valid */
122 if (d_mountpoint((struct dentry *)dentry))
125 if (d_lustre_invalid(dentry))
131 static inline int return_if_equal(struct ldlm_lock *lock, void *data)
134 (LDLM_FL_CANCELING | LDLM_FL_DISCARD_DATA)) ==
135 (LDLM_FL_CANCELING | LDLM_FL_DISCARD_DATA))
136 return LDLM_ITER_CONTINUE;
137 return LDLM_ITER_STOP;
140 /* find any ldlm lock of the inode in mdc and lov
144 static int find_cbdata(struct inode *inode)
146 struct ll_sb_info *sbi = ll_i2sbi(inode);
147 struct lov_stripe_md *lsm;
152 rc = md_find_cbdata(sbi->ll_md_exp, ll_inode2fid(inode),
153 return_if_equal, NULL);
157 lsm = ccc_inode_lsm_get(inode);
161 rc = obd_find_cbdata(sbi->ll_dt_exp, lsm, return_if_equal, NULL);
162 ccc_inode_lsm_put(inode, lsm);
168 * Called when last reference to a dentry is dropped and dcache wants to know
169 * whether or not it should cache it:
170 * - return 1 to delete the dentry immediately
171 * - return 0 to cache the dentry
172 * Should NOT be called with the dcache lock, see fs/dcache.c
174 static int ll_ddelete(HAVE_D_DELETE_CONST struct dentry *de)
179 CDEBUG(D_DENTRY, "%s dentry %.*s (%p, parent %p, inode %p) %s%s\n",
180 d_lustre_invalid((struct dentry *)de) ? "deleting" : "keeping",
181 de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
182 d_unhashed((struct dentry *)de) ? "" : "hashed,",
183 list_empty(&de->d_subdirs) ? "" : "subdirs");
185 #ifdef HAVE_DCACHE_LOCK
186 LASSERT(d_refcount(de) == 0);
188 /* kernel >= 2.6.38 last refcount is decreased after this function. */
189 LASSERT(d_refcount(de) == 1);
192 /* Disable this piece of code temproarily because this is called
193 * inside dcache_lock so it's not appropriate to do lots of work
196 /* if not ldlm lock for this inode, set i_nlink to 0 so that
197 * this inode can be recycled later b=20433 */
198 if (de->d_inode && !find_cbdata(de->d_inode))
199 clear_nlink(de->d_inode);
202 if (d_lustre_invalid((struct dentry *)de))
207 static int ll_set_dd(struct dentry *de)
212 CDEBUG(D_DENTRY, "ldd on dentry %.*s (%p) parent %p inode %p refc %d\n",
213 de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
216 if (de->d_fsdata == NULL) {
217 struct ll_dentry_data *lld;
220 if (likely(lld != NULL)) {
221 spin_lock(&de->d_lock);
222 if (likely(de->d_fsdata == NULL))
226 spin_unlock(&de->d_lock);
235 int ll_dops_init(struct dentry *de, int block, int init_sa)
237 struct ll_dentry_data *lld = ll_d2d(de);
240 if (lld == NULL && block != 0) {
248 if (lld != NULL && init_sa != 0)
249 lld->lld_sa_generation = 0;
251 #ifdef HAVE_DCACHE_LOCK
252 de->d_op = &ll_d_ops;
254 /* kernel >= 2.6.38 d_op is set in d_alloc() */
255 LASSERT(de->d_op == &ll_d_ops);
260 void ll_intent_drop_lock(struct lookup_intent *it)
262 struct lustre_handle *handle;
264 if (it->it_op && it->d.lustre.it_lock_mode) {
265 handle = (struct lustre_handle *)&it->d.lustre.it_lock_handle;
266 CDEBUG(D_DLMTRACE, "releasing lock with cookie "LPX64
267 " from it %p\n", handle->cookie, it);
268 ldlm_lock_decref(handle, it->d.lustre.it_lock_mode);
270 /* bug 494: intent_release may be called multiple times, from
271 * this thread and we don't want to double-decref this lock */
272 it->d.lustre.it_lock_mode = 0;
276 void ll_intent_release(struct lookup_intent *it)
280 CDEBUG(D_INFO, "intent %p released\n", it);
281 ll_intent_drop_lock(it);
282 /* We are still holding extra reference on a request, need to free it */
283 if (it_disposition(it, DISP_ENQ_OPEN_REF))
284 ptlrpc_req_finished(it->d.lustre.it_data); /* ll_file_open */
285 if (it_disposition(it, DISP_ENQ_CREATE_REF)) /* create rec */
286 ptlrpc_req_finished(it->d.lustre.it_data);
287 if (it_disposition(it, DISP_ENQ_COMPLETE)) /* saved req from revalidate
289 ptlrpc_req_finished(it->d.lustre.it_data);
291 it->d.lustre.it_disposition = 0;
292 it->d.lustre.it_data = NULL;
296 void ll_invalidate_aliases(struct inode *inode)
298 struct dentry *dentry;
301 LASSERT(inode != NULL);
303 CDEBUG(D_INODE, "marking dentries for ino %lu/%u(%p) invalid\n",
304 inode->i_ino, inode->i_generation, inode);
306 ll_lock_dcache(inode);
307 cfs_list_for_each_entry(dentry, &inode->i_dentry, d_alias) {
308 CDEBUG(D_DENTRY, "dentry in drop %.*s (%p) parent %p "
309 "inode %p flags %d\n", dentry->d_name.len,
310 dentry->d_name.name, dentry, dentry->d_parent,
311 dentry->d_inode, dentry->d_flags);
313 if (dentry->d_name.len == 1 && dentry->d_name.name[0] == '/') {
314 CERROR("called on root (?) dentry=%p, inode=%p "
315 "ino=%lu\n", dentry, inode, inode->i_ino);
316 lustre_dump_dentry(dentry, 1);
317 libcfs_debug_dumpstack(NULL);
320 d_lustre_invalidate(dentry);
322 ll_unlock_dcache(inode);
327 int ll_revalidate_it_finish(struct ptlrpc_request *request,
328 struct lookup_intent *it,
337 if (it_disposition(it, DISP_LOOKUP_NEG))
340 rc = ll_prep_inode(&de->d_inode, request, NULL);
345 void ll_lookup_finish_locks(struct lookup_intent *it, struct dentry *dentry)
348 LASSERT(dentry != NULL);
350 if (it->d.lustre.it_lock_mode && dentry->d_inode != NULL) {
351 struct inode *inode = dentry->d_inode;
352 struct ll_sb_info *sbi = ll_i2sbi(dentry->d_inode);
354 CDEBUG(D_DLMTRACE, "setting l_data to inode %p (%lu/%u)\n",
355 inode, inode->i_ino, inode->i_generation);
356 ll_set_lock_data(sbi->ll_md_exp, inode, it, NULL);
359 /* drop lookup or getattr locks immediately */
360 if (it->it_op == IT_LOOKUP || it->it_op == IT_GETATTR) {
361 /* on 2.6 there are situation when several lookups and
362 * revalidations may be requested during single operation.
363 * therefore, we don't release intent here -bzzz */
364 ll_intent_drop_lock(it);
368 void ll_frob_intent(struct lookup_intent **itp, struct lookup_intent *deft)
370 struct lookup_intent *it = *itp;
372 if (!it || it->it_op == IT_GETXATTR)
377 int ll_revalidate_it(struct dentry *de, int lookup_flags,
378 struct lookup_intent *it)
380 struct md_op_data *op_data;
381 struct ptlrpc_request *req = NULL;
382 struct lookup_intent lookup_it = { .it_op = IT_LOOKUP };
383 struct obd_export *exp;
384 struct inode *parent = de->d_parent->d_inode;
388 CDEBUG(D_VFSTRACE, "VFS Op:name=%s,intent=%s\n", de->d_name.name,
391 if (de->d_inode == NULL) {
394 /* We can only use negative dentries if this is stat or lookup,
395 for opens and stuff we do need to query server. */
396 /* If there is IT_CREAT in intent op set, then we must throw
397 away this negative dentry and actually do the request to
398 kernel to create whatever needs to be created (if possible)*/
399 if (it && (it->it_op & IT_CREAT))
402 if (d_lustre_invalid(de))
405 ibits = MDS_INODELOCK_UPDATE;
406 rc = ll_have_md_lock(parent, &ibits, LCK_MINMODE);
410 /* Never execute intents for mount points.
411 * Attributes will be fixed up in ll_inode_revalidate_it */
412 if (d_mountpoint(de))
413 GOTO(out_sa, rc = 1);
415 /* need to get attributes in case root got changed from other client */
416 if (de == de->d_sb->s_root) {
417 rc = __ll_inode_revalidate_it(de, it, MDS_INODELOCK_LOOKUP);
423 exp = ll_i2mdexp(de->d_inode);
425 OBD_FAIL_TIMEOUT(OBD_FAIL_MDC_REVALIDATE_PAUSE, 5);
426 ll_frob_intent(&it, &lookup_it);
429 if (it->it_op == IT_LOOKUP && !d_lustre_invalid(de))
432 if (it->it_op == IT_OPEN) {
433 struct inode *inode = de->d_inode;
434 struct ll_inode_info *lli = ll_i2info(inode);
435 struct obd_client_handle **och_p;
440 * We used to check for MDS_INODELOCK_OPEN here, but in fact
441 * just having LOOKUP lock is enough to justify inode is the
442 * same. And if inode is the same and we have suitable
443 * openhandle, then there is no point in doing another OPEN RPC
444 * just to throw away newly received openhandle. There are no
445 * security implications too, if file owner or access mode is
446 * change, LOOKUP lock is revoked.
450 if (it->it_flags & FMODE_WRITE) {
451 och_p = &lli->lli_mds_write_och;
452 och_usecount = &lli->lli_open_fd_write_count;
453 } else if (it->it_flags & FMODE_EXEC) {
454 och_p = &lli->lli_mds_exec_och;
455 och_usecount = &lli->lli_open_fd_exec_count;
457 och_p = &lli->lli_mds_read_och;
458 och_usecount = &lli->lli_open_fd_read_count;
460 /* Check for the proper lock. */
461 ibits = MDS_INODELOCK_LOOKUP;
462 if (!ll_have_md_lock(inode, &ibits, LCK_MINMODE))
464 cfs_mutex_lock(&lli->lli_och_mutex);
465 if (*och_p) { /* Everything is open already, do nothing */
466 /*(*och_usecount)++; Do not let them steal our open
467 handle from under us */
468 SET_BUT_UNUSED(och_usecount);
469 /* XXX The code above was my original idea, but in case
470 we have the handle, but we cannot use it due to later
471 checks (e.g. O_CREAT|O_EXCL flags set), nobody
472 would decrement counter increased here. So we just
473 hope the lock won't be invalidated in between. But
474 if it would be, we'll reopen the open request to
475 MDS later during file open path */
476 cfs_mutex_unlock(&lli->lli_och_mutex);
479 cfs_mutex_unlock(&lli->lli_och_mutex);
483 if (it->it_op == IT_GETATTR) {
484 rc = ll_statahead_enter(parent, &de, 0);
487 else if (rc != -EAGAIN && rc != 0)
492 op_data = ll_prep_md_op_data(NULL, parent, de->d_inode,
493 de->d_name.name, de->d_name.len,
494 0, LUSTRE_OPC_ANY, NULL);
496 RETURN(PTR_ERR(op_data));
498 it->it_create_mode &= ~cfs_curproc_umask();
499 it->it_create_mode |= M_CHECK_STALE;
500 rc = md_intent_lock(exp, op_data, NULL, 0, it,
502 &req, ll_md_blocking_ast, 0);
503 it->it_create_mode &= ~M_CHECK_STALE;
504 ll_finish_md_op_data(op_data);
506 /* If req is NULL, then md_intent_lock only tried to do a lock match;
507 * if all was well, it will return 1 if it found locks, 0 otherwise. */
508 if (req == NULL && rc >= 0) {
516 CDEBUG(D_INFO, "ll_intent_lock: rc %d : it->it_status "
517 "%d\n", rc, it->d.lustre.it_status);
523 rc = ll_revalidate_it_finish(req, it, de);
525 if (rc != -ESTALE && rc != -ENOENT)
526 ll_intent_release(it);
530 if ((it->it_op & IT_OPEN) && de->d_inode &&
531 !S_ISREG(de->d_inode->i_mode) &&
532 !S_ISDIR(de->d_inode->i_mode)) {
533 ll_release_openhandle(de, it);
538 /* We do not free request as it may be reused during following lookup
539 * (see comment in mdc/mdc_locks.c::mdc_intent_lock()), request will
540 * be freed in ll_lookup_it or in ll_intent_release. But if
541 * request was not completed, we need to free it. (bug 5154, 9903) */
542 if (req != NULL && !it_disposition(it, DISP_ENQ_COMPLETE))
543 ptlrpc_req_finished(req);
545 ll_invalidate_aliases(de->d_inode);
549 CDEBUG(D_DENTRY, "revalidated dentry %.*s (%p) parent %p "
550 "inode %p refc %d\n", de->d_name.len,
551 de->d_name.name, de, de->d_parent, de->d_inode,
553 ll_set_lock_data(exp, de->d_inode, it, &bits);
554 if ((bits & MDS_INODELOCK_LOOKUP) && d_lustre_invalid(de))
555 d_lustre_revalidate(de);
556 ll_lookup_finish_locks(it, de);
560 if (it != NULL && it->it_op == IT_GETATTR && rc > 0)
561 ll_statahead_mark(parent, de);
565 * This part is here to combat evil-evil race in real_lookup on 2.6
566 * kernels. The race details are: We enter do_lookup() looking for some
567 * name, there is nothing in dcache for this name yet and d_lookup()
568 * returns NULL. We proceed to real_lookup(), and while we do this,
569 * another process does open on the same file we looking up (most simple
570 * reproducer), open succeeds and the dentry is added. Now back to
571 * us. In real_lookup() we do d_lookup() again and suddenly find the
572 * dentry, so we call d_revalidate on it, but there is no lock, so
573 * without this code we would return 0, but unpatched real_lookup just
574 * returns -ENOENT in such a case instead of retrying the lookup. Once
575 * this is dealt with in real_lookup(), all of this ugly mess can go and
576 * we can just check locks in ->d_revalidate without doing any RPCs
580 if (it != &lookup_it) {
581 /* MDS_INODELOCK_UPDATE needed for IT_GETATTR case. */
582 if (it->it_op == IT_GETATTR)
583 lookup_it.it_op = IT_GETATTR;
584 ll_lookup_finish_locks(it, de);
588 /* Do real lookup here. */
589 op_data = ll_prep_md_op_data(NULL, parent, NULL, de->d_name.name,
590 de->d_name.len, 0, (it->it_op & IT_CREAT ?
592 LUSTRE_OPC_ANY), NULL);
594 RETURN(PTR_ERR(op_data));
596 rc = md_intent_lock(exp, op_data, NULL, 0, it, 0, &req,
597 ll_md_blocking_ast, 0);
599 struct mdt_body *mdt_body;
600 struct lu_fid fid = {.f_seq = 0, .f_oid = 0, .f_ver = 0};
601 mdt_body = req_capsule_server_get(&req->rq_pill, &RMF_MDT_BODY);
604 fid = *ll_inode2fid(de->d_inode);
606 /* see if we got same inode, if not - return error */
607 if (lu_fid_eq(&fid, &mdt_body->fid1)) {
608 ll_finish_md_op_data(op_data);
610 goto revalidate_finish;
612 ll_intent_release(it);
614 ll_finish_md_op_data(op_data);
619 * For rc == 1 case, should not return directly to prevent losing
620 * statahead windows; for rc == 0 case, the "lookup" will be done later.
622 if (it != NULL && it->it_op == IT_GETATTR && rc == 1)
623 ll_statahead_enter(parent, &de, 1);
627 int ll_revalidate_nd(struct dentry *dentry, struct nameidata *nd)
632 #ifndef HAVE_DCACHE_LOCK
633 /* kernel >= 2.6.38 supports rcu-walk, but lustre doesn't. */
634 if (nd->flags & LOOKUP_RCU)
638 if (nd && !(nd->flags & (LOOKUP_CONTINUE|LOOKUP_PARENT))) {
639 struct lookup_intent *it;
641 it = ll_convert_intent(&nd->intent.open, nd->flags);
645 if (it->it_op == (IT_OPEN|IT_CREAT) &&
646 nd->intent.open.flags & O_EXCL) {
647 CDEBUG(D_VFSTRACE, "create O_EXCL, returning 0\n");
652 rc = ll_revalidate_it(dentry, nd->flags, it);
654 if (rc && (nd->flags & LOOKUP_OPEN) &&
655 it_disposition(it, DISP_OPEN_OPEN)) {/*Open*/
656 // XXX Code duplication with ll_lookup_nd
657 if (S_ISFIFO(dentry->d_inode->i_mode)) {
658 // We cannot call open here as it would
661 (struct ptlrpc_request *)
662 it->d.lustre.it_data);
666 nd->intent.open.file->private_data = it;
667 filp = lookup_instantiate_filp(nd, dentry,NULL);
672 if (!rc && (nd->flags & LOOKUP_CREATE) &&
673 it_disposition(it, DISP_OPEN_CREATE)) {
674 /* We created something but we may only return
675 * negative dentry here, so save request in dentry,
676 * if lookup will be called later on, it will
677 * pick the request, otherwise it would be freed
679 ll_d2d(dentry)->lld_it = it;
680 it = NULL; /* avoid freeing */
685 ll_intent_release(it);
686 OBD_FREE(it, sizeof(*it));
689 rc = ll_revalidate_it(dentry, 0, NULL);
695 void ll_d_iput(struct dentry *de, struct inode *inode)
698 if (!find_cbdata(inode))
703 struct dentry_operations ll_d_ops = {
704 .d_revalidate = ll_revalidate_nd,
705 .d_release = ll_release,
706 .d_delete = ll_ddelete,
708 .d_compare = ll_dcompare,