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, 2012, Intel Corporation.
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 if (it->it_op && it->d.lustre.it_lock_mode) {
263 struct lustre_handle handle;
265 handle.cookie = it->d.lustre.it_lock_handle;
267 CDEBUG(D_DLMTRACE, "releasing lock with cookie "LPX64
268 " from it %p\n", handle.cookie, it);
269 ldlm_lock_decref(&handle, it->d.lustre.it_lock_mode);
271 /* bug 494: intent_release may be called multiple times, from
272 * this thread and we don't want to double-decref this lock */
273 it->d.lustre.it_lock_mode = 0;
274 if (it->d.lustre.it_remote_lock_mode != 0) {
275 handle.cookie = it->d.lustre.it_remote_lock_handle;
277 CDEBUG(D_DLMTRACE, "releasing remote lock with cookie"
278 LPX64" from it %p\n", handle.cookie, it);
279 ldlm_lock_decref(&handle,
280 it->d.lustre.it_remote_lock_mode);
281 it->d.lustre.it_remote_lock_mode = 0;
286 void ll_intent_release(struct lookup_intent *it)
290 CDEBUG(D_INFO, "intent %p released\n", it);
291 ll_intent_drop_lock(it);
292 /* We are still holding extra reference on a request, need to free it */
293 if (it_disposition(it, DISP_ENQ_OPEN_REF))
294 ptlrpc_req_finished(it->d.lustre.it_data); /* ll_file_open */
295 if (it_disposition(it, DISP_ENQ_CREATE_REF)) /* create rec */
296 ptlrpc_req_finished(it->d.lustre.it_data);
297 if (it_disposition(it, DISP_ENQ_COMPLETE)) /* saved req from revalidate
299 ptlrpc_req_finished(it->d.lustre.it_data);
301 it->d.lustre.it_disposition = 0;
302 it->d.lustre.it_data = NULL;
306 void ll_invalidate_aliases(struct inode *inode)
308 struct dentry *dentry;
309 struct ll_d_hlist_node *p;
312 LASSERT(inode != NULL);
314 CDEBUG(D_INODE, "marking dentries for ino %lu/%u(%p) invalid\n",
315 inode->i_ino, inode->i_generation, inode);
317 ll_lock_dcache(inode);
318 ll_d_hlist_for_each_entry(dentry, p, &inode->i_dentry, d_alias) {
319 CDEBUG(D_DENTRY, "dentry in drop %.*s (%p) parent %p "
320 "inode %p flags %d\n", dentry->d_name.len,
321 dentry->d_name.name, dentry, dentry->d_parent,
322 dentry->d_inode, dentry->d_flags);
324 if (dentry->d_name.len == 1 && dentry->d_name.name[0] == '/') {
325 CERROR("called on root (?) dentry=%p, inode=%p "
326 "ino=%lu\n", dentry, inode, inode->i_ino);
327 lustre_dump_dentry(dentry, 1);
328 libcfs_debug_dumpstack(NULL);
331 d_lustre_invalidate(dentry);
333 ll_unlock_dcache(inode);
338 int ll_revalidate_it_finish(struct ptlrpc_request *request,
339 struct lookup_intent *it,
348 if (it_disposition(it, DISP_LOOKUP_NEG))
351 rc = ll_prep_inode(&de->d_inode, request, NULL, it);
356 void ll_lookup_finish_locks(struct lookup_intent *it, struct dentry *dentry)
359 LASSERT(dentry != NULL);
361 if (it->d.lustre.it_lock_mode && dentry->d_inode != NULL) {
362 struct inode *inode = dentry->d_inode;
363 struct ll_sb_info *sbi = ll_i2sbi(dentry->d_inode);
365 CDEBUG(D_DLMTRACE, "setting l_data to inode %p (%lu/%u)\n",
366 inode, inode->i_ino, inode->i_generation);
367 ll_set_lock_data(sbi->ll_md_exp, inode, it, NULL);
370 /* drop lookup or getattr locks immediately */
371 if (it->it_op == IT_LOOKUP || it->it_op == IT_GETATTR) {
372 /* on 2.6 there are situation when several lookups and
373 * revalidations may be requested during single operation.
374 * therefore, we don't release intent here -bzzz */
375 ll_intent_drop_lock(it);
379 void ll_frob_intent(struct lookup_intent **itp, struct lookup_intent *deft)
381 struct lookup_intent *it = *itp;
383 if (!it || it->it_op == IT_GETXATTR)
388 int ll_revalidate_it(struct dentry *de, int lookup_flags,
389 struct lookup_intent *it)
391 struct md_op_data *op_data;
392 struct ptlrpc_request *req = NULL;
393 struct lookup_intent lookup_it = { .it_op = IT_LOOKUP };
394 struct obd_export *exp;
395 struct inode *parent = de->d_parent->d_inode;
399 CDEBUG(D_VFSTRACE, "VFS Op:name=%s,intent=%s\n", de->d_name.name,
402 if (de->d_inode == NULL) {
405 /* We can only use negative dentries if this is stat or lookup,
406 for opens and stuff we do need to query server. */
407 /* If there is IT_CREAT in intent op set, then we must throw
408 away this negative dentry and actually do the request to
409 kernel to create whatever needs to be created (if possible)*/
410 if (it && (it->it_op & IT_CREAT))
413 if (d_lustre_invalid(de))
416 ibits = MDS_INODELOCK_UPDATE;
417 rc = ll_have_md_lock(parent, &ibits, LCK_MINMODE);
421 /* Never execute intents for mount points.
422 * Attributes will be fixed up in ll_inode_revalidate_it */
423 if (d_mountpoint(de))
424 GOTO(out_sa, rc = 1);
426 /* need to get attributes in case root got changed from other client */
427 if (de == de->d_sb->s_root) {
428 rc = __ll_inode_revalidate_it(de, it, MDS_INODELOCK_LOOKUP);
434 exp = ll_i2mdexp(de->d_inode);
436 OBD_FAIL_TIMEOUT(OBD_FAIL_MDC_REVALIDATE_PAUSE, 5);
437 ll_frob_intent(&it, &lookup_it);
440 if (it->it_op == IT_LOOKUP && !d_lustre_invalid(de))
443 if (it->it_op == IT_OPEN) {
444 struct inode *inode = de->d_inode;
445 struct ll_inode_info *lli = ll_i2info(inode);
446 struct obd_client_handle **och_p;
451 * We used to check for MDS_INODELOCK_OPEN here, but in fact
452 * just having LOOKUP lock is enough to justify inode is the
453 * same. And if inode is the same and we have suitable
454 * openhandle, then there is no point in doing another OPEN RPC
455 * just to throw away newly received openhandle. There are no
456 * security implications too, if file owner or access mode is
457 * change, LOOKUP lock is revoked.
461 if (it->it_flags & FMODE_WRITE) {
462 och_p = &lli->lli_mds_write_och;
463 och_usecount = &lli->lli_open_fd_write_count;
464 } else if (it->it_flags & FMODE_EXEC) {
465 och_p = &lli->lli_mds_exec_och;
466 och_usecount = &lli->lli_open_fd_exec_count;
468 och_p = &lli->lli_mds_read_och;
469 och_usecount = &lli->lli_open_fd_read_count;
471 /* Check for the proper lock. */
472 ibits = MDS_INODELOCK_LOOKUP;
473 if (!ll_have_md_lock(inode, &ibits, LCK_MINMODE))
475 mutex_lock(&lli->lli_och_mutex);
476 if (*och_p) { /* Everything is open already, do nothing */
477 /*(*och_usecount)++; Do not let them steal our open
478 handle from under us */
479 SET_BUT_UNUSED(och_usecount);
480 /* XXX The code above was my original idea, but in case
481 we have the handle, but we cannot use it due to later
482 checks (e.g. O_CREAT|O_EXCL flags set), nobody
483 would decrement counter increased here. So we just
484 hope the lock won't be invalidated in between. But
485 if it would be, we'll reopen the open request to
486 MDS later during file open path */
487 mutex_unlock(&lli->lli_och_mutex);
490 mutex_unlock(&lli->lli_och_mutex);
494 if (it->it_op == IT_GETATTR) {
495 rc = ll_statahead_enter(parent, &de, 0);
498 else if (rc != -EAGAIN && rc != 0)
503 op_data = ll_prep_md_op_data(NULL, parent, de->d_inode,
504 de->d_name.name, de->d_name.len,
505 0, LUSTRE_OPC_ANY, NULL);
507 RETURN(PTR_ERR(op_data));
509 if (!IS_POSIXACL(parent) || !exp_connect_umask(exp))
510 it->it_create_mode &= ~cfs_curproc_umask();
511 it->it_create_mode |= M_CHECK_STALE;
512 rc = md_intent_lock(exp, op_data, NULL, 0, it,
514 &req, ll_md_blocking_ast, 0);
515 it->it_create_mode &= ~M_CHECK_STALE;
516 ll_finish_md_op_data(op_data);
518 /* If req is NULL, then md_intent_lock only tried to do a lock match;
519 * if all was well, it will return 1 if it found locks, 0 otherwise. */
520 if (req == NULL && rc >= 0) {
528 CDEBUG(D_INFO, "ll_intent_lock: rc %d : it->it_status "
529 "%d\n", rc, it->d.lustre.it_status);
535 rc = ll_revalidate_it_finish(req, it, de);
537 if (rc != -ESTALE && rc != -ENOENT)
538 ll_intent_release(it);
542 if ((it->it_op & IT_OPEN) && de->d_inode &&
543 !S_ISREG(de->d_inode->i_mode) &&
544 !S_ISDIR(de->d_inode->i_mode)) {
545 ll_release_openhandle(de, it);
550 /* We do not free request as it may be reused during following lookup
551 * (see comment in mdc/mdc_locks.c::mdc_intent_lock()), request will
552 * be freed in ll_lookup_it or in ll_intent_release. But if
553 * request was not completed, we need to free it. (bug 5154, 9903) */
554 if (req != NULL && !it_disposition(it, DISP_ENQ_COMPLETE))
555 ptlrpc_req_finished(req);
557 /* mdt may grant layout lock for the newly created file, so
558 * release the lock to avoid leaking */
559 ll_intent_drop_lock(it);
560 ll_invalidate_aliases(de->d_inode);
563 __u64 matched_bits = 0;
565 CDEBUG(D_DENTRY, "revalidated dentry %.*s (%p) parent %p "
566 "inode %p refc %d\n", de->d_name.len,
567 de->d_name.name, de, de->d_parent, de->d_inode,
570 ll_set_lock_data(exp, de->d_inode, it, &bits);
572 /* Note: We have to match both LOOKUP and PERM lock
573 * here to make sure the dentry is valid and no one
574 * changing the permission.
575 * But if the client connects < 2.4 server, which will
576 * only grant LOOKUP lock, so we can only Match LOOKUP
577 * lock for old server */
578 if (exp_connect_flags(ll_i2mdexp(de->d_inode)) &&
579 OBD_CONNECT_LVB_TYPE)
581 MDS_INODELOCK_LOOKUP | MDS_INODELOCK_PERM;
583 matched_bits = MDS_INODELOCK_LOOKUP;
585 if (((bits & matched_bits) == matched_bits) &&
586 d_lustre_invalid(de))
587 d_lustre_revalidate(de);
588 ll_lookup_finish_locks(it, de);
592 if (it != NULL && it->it_op == IT_GETATTR && rc > 0)
593 ll_statahead_mark(parent, de);
597 * This part is here to combat evil-evil race in real_lookup on 2.6
598 * kernels. The race details are: We enter do_lookup() looking for some
599 * name, there is nothing in dcache for this name yet and d_lookup()
600 * returns NULL. We proceed to real_lookup(), and while we do this,
601 * another process does open on the same file we looking up (most simple
602 * reproducer), open succeeds and the dentry is added. Now back to
603 * us. In real_lookup() we do d_lookup() again and suddenly find the
604 * dentry, so we call d_revalidate on it, but there is no lock, so
605 * without this code we would return 0, but unpatched real_lookup just
606 * returns -ENOENT in such a case instead of retrying the lookup. Once
607 * this is dealt with in real_lookup(), all of this ugly mess can go and
608 * we can just check locks in ->d_revalidate without doing any RPCs
612 if (it != &lookup_it) {
613 /* MDS_INODELOCK_UPDATE needed for IT_GETATTR case. */
614 if (it->it_op == IT_GETATTR)
615 lookup_it.it_op = IT_GETATTR;
616 ll_lookup_finish_locks(it, de);
620 /* Do real lookup here. */
621 op_data = ll_prep_md_op_data(NULL, parent, NULL, de->d_name.name,
622 de->d_name.len, 0, (it->it_op & IT_CREAT ?
624 LUSTRE_OPC_ANY), NULL);
626 RETURN(PTR_ERR(op_data));
628 rc = md_intent_lock(exp, op_data, NULL, 0, it, 0, &req,
629 ll_md_blocking_ast, 0);
631 struct mdt_body *mdt_body;
632 struct lu_fid fid = {.f_seq = 0, .f_oid = 0, .f_ver = 0};
633 mdt_body = req_capsule_server_get(&req->rq_pill, &RMF_MDT_BODY);
636 fid = *ll_inode2fid(de->d_inode);
638 /* see if we got same inode, if not - return error */
639 if (lu_fid_eq(&fid, &mdt_body->fid1)) {
640 ll_finish_md_op_data(op_data);
642 goto revalidate_finish;
644 ll_intent_release(it);
646 ll_finish_md_op_data(op_data);
651 * For rc == 1 case, should not return directly to prevent losing
652 * statahead windows; for rc == 0 case, the "lookup" will be done later.
654 if (it != NULL && it->it_op == IT_GETATTR && rc == 1)
655 ll_statahead_enter(parent, &de, 1);
659 #ifdef HAVE_IOP_ATOMIC_OPEN
661 * Always trust cached dentries. Update statahead window if necessary.
663 int ll_revalidate_nd(struct dentry *dentry, unsigned int flags)
665 struct inode *parent = dentry->d_parent->d_inode;
669 CDEBUG(D_VFSTRACE, "VFS Op:name=%s,flags=%u\n",
670 dentry->d_name.name, flags);
672 if (!(flags & (LOOKUP_PARENT|LOOKUP_OPEN|LOOKUP_CREATE)) &&
673 ll_need_statahead(parent, dentry) > 0) {
674 if (flags & LOOKUP_RCU)
677 if (dentry->d_inode == NULL)
679 do_statahead_enter(parent, &dentry, unplug);
680 ll_statahead_mark(parent, dentry);
686 #else /* !HAVE_IOP_ATOMIC_OPEN */
687 int ll_revalidate_nd(struct dentry *dentry, struct nameidata *nd)
692 #ifndef HAVE_DCACHE_LOCK
693 /* kernel >= 2.6.38 supports rcu-walk, but lustre doesn't. */
694 if (nd->flags & LOOKUP_RCU)
698 if (nd && !(nd->flags & (LOOKUP_CONTINUE|LOOKUP_PARENT))) {
699 struct lookup_intent *it;
701 it = ll_convert_intent(&nd->intent.open, nd->flags);
705 if (it->it_op == (IT_OPEN|IT_CREAT) &&
706 nd->intent.open.flags & O_EXCL) {
707 CDEBUG(D_VFSTRACE, "create O_EXCL, returning 0\n");
712 rc = ll_revalidate_it(dentry, nd->flags, it);
714 if (rc && (nd->flags & LOOKUP_OPEN) &&
715 it_disposition(it, DISP_OPEN_OPEN)) {/*Open*/
716 // XXX Code duplication with ll_lookup_nd
717 if (S_ISFIFO(dentry->d_inode->i_mode)) {
718 // We cannot call open here as it would
721 (struct ptlrpc_request *)
722 it->d.lustre.it_data);
726 nd->intent.open.file->private_data = it;
727 filp = lookup_instantiate_filp(nd, dentry,NULL);
732 if (!rc && (nd->flags & LOOKUP_CREATE) &&
733 it_disposition(it, DISP_OPEN_CREATE)) {
734 /* We created something but we may only return
735 * negative dentry here, so save request in dentry,
736 * if lookup will be called later on, it will
737 * pick the request, otherwise it would be freed
739 ll_d2d(dentry)->lld_it = it;
740 it = NULL; /* avoid freeing */
745 ll_intent_release(it);
746 OBD_FREE(it, sizeof(*it));
749 rc = ll_revalidate_it(dentry, 0, NULL);
754 #endif /* HAVE_IOP_ATOMIC_OPEN */
756 void ll_d_iput(struct dentry *de, struct inode *inode)
759 if (!find_cbdata(inode))
764 struct dentry_operations ll_d_ops = {
765 .d_revalidate = ll_revalidate_nd,
766 .d_release = ll_release,
767 .d_delete = ll_ddelete,
769 .d_compare = ll_dcompare,