1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
6 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 only,
10 * as published by the Free Software Foundation.
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License version 2 for more details (a copy is included
16 * in the LICENSE file that accompanied this code).
18 * You should have received a copy of the GNU General Public License
19 * version 2 along with this program; If not, see
20 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
22 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
23 * CA 95054 USA or visit www.sun.com if you need additional information or
29 * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
30 * Use is subject to license terms.
32 * Copyright (c) 2011 Whamcloud, Inc.
36 * This file is part of Lustre, http://www.lustre.org/
37 * Lustre is a trademark of Sun Microsystems, Inc.
41 #include <linux/sched.h>
42 #include <linux/smp_lock.h>
43 #include <linux/quotaops.h>
45 #define DEBUG_SUBSYSTEM S_LLITE
47 #include <obd_support.h>
48 #include <lustre_lite.h>
49 #include <lustre/lustre_idl.h>
50 #include <lustre_dlm.h>
51 //#include <lustre_ver.h>
52 //#include <lustre_version.h>
54 #include "llite_internal.h"
56 cfs_spinlock_t ll_lookup_lock = CFS_SPIN_LOCK_UNLOCKED;
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) */
70 ll_intent_release(lld->lld_it);
71 OBD_FREE(lld->lld_it, sizeof(*lld->lld_it));
73 LASSERT(lld->lld_cwd_count == 0);
74 LASSERT(lld->lld_mnt_count == 0);
75 OBD_FREE(de->d_fsdata, sizeof(*lld));
80 /* Compare if two dentries are the same. Don't match if the existing dentry
81 * is marked DCACHE_LUSTRE_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 int ll_dcompare(struct dentry *parent, struct qstr *d_name, struct qstr *name)
89 struct dentry *dchild;
92 if (d_name->len != name->len)
95 if (memcmp(d_name->name, name->name, name->len))
98 /* XXX: d_name must be in-dentry structure */
99 dchild = container_of(d_name, struct dentry, d_name); /* ugh */
101 CDEBUG(D_DENTRY,"found name %.*s(%p) - flags %d/%x - refc %d\n",
102 name->len, name->name, dchild,
103 d_mountpoint(dchild), dchild->d_flags & DCACHE_LUSTRE_INVALID,
104 atomic_read(&dchild->d_count));
106 /* mountpoint is always valid */
107 if (d_mountpoint(dchild))
110 if (dchild->d_flags & DCACHE_LUSTRE_INVALID)
116 static inline int return_if_equal(struct ldlm_lock *lock, void *data)
119 (LDLM_FL_CANCELING | LDLM_FL_DISCARD_DATA)) ==
120 (LDLM_FL_CANCELING | LDLM_FL_DISCARD_DATA))
121 return LDLM_ITER_CONTINUE;
122 return LDLM_ITER_STOP;
125 /* find any ldlm lock of the inode in mdc and lov
129 static int find_cbdata(struct inode *inode)
131 struct ll_inode_info *lli = ll_i2info(inode);
132 struct ll_sb_info *sbi = ll_i2sbi(inode);
137 rc = md_find_cbdata(sbi->ll_md_exp, ll_inode2fid(inode),
138 return_if_equal, NULL);
143 rc = obd_find_cbdata(sbi->ll_dt_exp, lli->lli_smd,
144 return_if_equal, NULL);
150 * Called when last reference to a dentry is dropped and dcache wants to know
151 * whether or not it should cache it:
152 * - return 1 to delete the dentry immediately
153 * - return 0 to cache the dentry
154 * Should NOT be called with the dcache lock, see fs/dcache.c
156 static int ll_ddelete(struct dentry *de)
161 CDEBUG(D_DENTRY, "%s dentry %.*s (%p, parent %p, inode %p) %s%s\n",
162 (de->d_flags & DCACHE_LUSTRE_INVALID ? "deleting" : "keeping"),
163 de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
164 d_unhashed(de) ? "" : "hashed,",
165 list_empty(&de->d_subdirs) ? "" : "subdirs");
167 /* if not ldlm lock for this inode, set i_nlink to 0 so that
168 * this inode can be recycled later b=20433 */
169 LASSERT(atomic_read(&de->d_count) == 0);
170 if (de->d_inode && !find_cbdata(de->d_inode))
171 de->d_inode->i_nlink = 0;
173 if (de->d_flags & DCACHE_LUSTRE_INVALID)
179 static int ll_set_dd(struct dentry *de)
184 CDEBUG(D_DENTRY, "ldd on dentry %.*s (%p) parent %p inode %p refc %d\n",
185 de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
186 atomic_read(&de->d_count));
188 if (de->d_fsdata == NULL) {
189 struct ll_dentry_data *lld;
192 if (likely(lld != NULL)) {
194 if (likely(de->d_fsdata == NULL))
207 int ll_dops_init(struct dentry *de, int block, int init_sa)
209 struct ll_dentry_data *lld = ll_d2d(de);
212 if (lld == NULL && block != 0) {
220 if (lld != NULL && init_sa != 0)
221 lld->lld_sa_generation = 0;
223 de->d_op = &ll_d_ops;
227 void ll_intent_drop_lock(struct lookup_intent *it)
229 struct lustre_handle *handle;
231 if (it->it_op && it->d.lustre.it_lock_mode) {
232 handle = (struct lustre_handle *)&it->d.lustre.it_lock_handle;
233 CDEBUG(D_DLMTRACE, "releasing lock with cookie "LPX64
234 " from it %p\n", handle->cookie, it);
235 ldlm_lock_decref(handle, it->d.lustre.it_lock_mode);
237 /* bug 494: intent_release may be called multiple times, from
238 * this thread and we don't want to double-decref this lock */
239 it->d.lustre.it_lock_mode = 0;
243 void ll_intent_release(struct lookup_intent *it)
247 CDEBUG(D_INFO, "intent %p released\n", it);
248 ll_intent_drop_lock(it);
249 /* We are still holding extra reference on a request, need to free it */
250 if (it_disposition(it, DISP_ENQ_OPEN_REF))
251 ptlrpc_req_finished(it->d.lustre.it_data); /* ll_file_open */
252 if (it_disposition(it, DISP_ENQ_CREATE_REF)) /* create rec */
253 ptlrpc_req_finished(it->d.lustre.it_data);
254 if (it_disposition(it, DISP_ENQ_COMPLETE)) /* saved req from revalidate
256 ptlrpc_req_finished(it->d.lustre.it_data);
258 it->d.lustre.it_disposition = 0;
259 it->d.lustre.it_data = NULL;
263 /* Drop dentry if it is not used already, unhash otherwise.
264 Should be called with dcache lock held!
265 Returns: 1 if dentry was dropped, 0 if unhashed. */
266 int ll_drop_dentry(struct dentry *dentry)
269 if (atomic_read(&dentry->d_count) == 0) {
270 CDEBUG(D_DENTRY, "deleting dentry %.*s (%p) parent %p "
271 "inode %p\n", dentry->d_name.len,
272 dentry->d_name.name, dentry, dentry->d_parent,
276 unlock_dentry(dentry);
277 spin_unlock(&dcache_lock);
278 cfs_spin_unlock(&ll_lookup_lock);
280 cfs_spin_lock(&ll_lookup_lock);
281 spin_lock(&dcache_lock);
284 /* disconected dentry can not be find without lookup, because we
285 * not need his to unhash or mark invalid. */
286 if (dentry->d_flags & DCACHE_DISCONNECTED) {
287 unlock_dentry(dentry);
291 if (!(dentry->d_flags & DCACHE_LUSTRE_INVALID)) {
292 CDEBUG(D_DENTRY, "unhashing dentry %.*s (%p) parent %p "
293 "inode %p refc %d\n", dentry->d_name.len,
294 dentry->d_name.name, dentry, dentry->d_parent,
295 dentry->d_inode, atomic_read(&dentry->d_count));
296 /* actually we don't unhash the dentry, rather just
297 * mark it inaccessible for to __d_lookup(). otherwise
298 * sys_getcwd() could return -ENOENT -bzzz */
299 dentry->d_flags |= DCACHE_LUSTRE_INVALID;
300 if (!dentry->d_inode || !S_ISDIR(dentry->d_inode->i_mode))
303 unlock_dentry(dentry);
307 void ll_unhash_aliases(struct inode *inode)
309 struct list_head *tmp, *head;
313 CERROR("unexpected NULL inode, tell phil\n");
317 CDEBUG(D_INODE, "marking dentries for ino %lu/%u(%p) invalid\n",
318 inode->i_ino, inode->i_generation, inode);
320 head = &inode->i_dentry;
321 cfs_spin_lock(&ll_lookup_lock);
322 spin_lock(&dcache_lock);
325 while ((tmp = tmp->next) != head) {
326 struct dentry *dentry = list_entry(tmp, struct dentry, d_alias);
328 CDEBUG(D_DENTRY, "dentry in drop %.*s (%p) parent %p "
329 "inode %p flags %d\n", dentry->d_name.len,
330 dentry->d_name.name, dentry, dentry->d_parent,
331 dentry->d_inode, dentry->d_flags);
333 if (dentry->d_name.len == 1 && dentry->d_name.name[0] == '/') {
334 CERROR("called on root (?) dentry=%p, inode=%p "
335 "ino=%lu\n", dentry, inode, inode->i_ino);
336 lustre_dump_dentry(dentry, 1);
337 libcfs_debug_dumpstack(NULL);
340 if (ll_drop_dentry(dentry))
343 spin_unlock(&dcache_lock);
344 cfs_spin_unlock(&ll_lookup_lock);
349 int ll_revalidate_it_finish(struct ptlrpc_request *request,
350 struct lookup_intent *it,
359 if (it_disposition(it, DISP_LOOKUP_NEG))
362 rc = ll_prep_inode(&de->d_inode, request, NULL);
367 void ll_lookup_finish_locks(struct lookup_intent *it, struct dentry *dentry)
370 LASSERT(dentry != NULL);
372 if (it->d.lustre.it_lock_mode && dentry->d_inode != NULL) {
373 struct inode *inode = dentry->d_inode;
374 struct ll_sb_info *sbi = ll_i2sbi(dentry->d_inode);
376 CDEBUG(D_DLMTRACE, "setting l_data to inode %p (%lu/%u)\n",
377 inode, inode->i_ino, inode->i_generation);
378 md_set_lock_data(sbi->ll_md_exp, &it->d.lustre.it_lock_handle,
382 /* drop lookup or getattr locks immediately */
383 if (it->it_op == IT_LOOKUP || it->it_op == IT_GETATTR) {
384 /* on 2.6 there are situation when several lookups and
385 * revalidations may be requested during single operation.
386 * therefore, we don't release intent here -bzzz */
387 ll_intent_drop_lock(it);
391 void ll_frob_intent(struct lookup_intent **itp, struct lookup_intent *deft)
393 struct lookup_intent *it = *itp;
395 if (!it || it->it_op == IT_GETXATTR)
400 int ll_revalidate_it(struct dentry *de, int lookup_flags,
401 struct lookup_intent *it)
403 struct md_op_data *op_data;
404 struct ptlrpc_request *req = NULL;
405 struct lookup_intent lookup_it = { .it_op = IT_LOOKUP };
406 struct obd_export *exp;
407 struct inode *parent = de->d_parent->d_inode;
411 CDEBUG(D_VFSTRACE, "VFS Op:name=%s,intent=%s\n", de->d_name.name,
414 if (de->d_inode == NULL) {
417 /* We can only use negative dentries if this is stat or lookup,
418 for opens and stuff we do need to query server. */
419 /* If there is IT_CREAT in intent op set, then we must throw
420 away this negative dentry and actually do the request to
421 kernel to create whatever needs to be created (if possible)*/
422 if (it && (it->it_op & IT_CREAT))
425 if (de->d_flags & DCACHE_LUSTRE_INVALID)
428 ibits = MDS_INODELOCK_UPDATE;
429 rc = ll_have_md_lock(parent, &ibits, LCK_MINMODE);
433 /* Never execute intents for mount points.
434 * Attributes will be fixed up in ll_inode_revalidate_it */
435 if (d_mountpoint(de))
436 GOTO(out_sa, rc = 1);
438 /* need to get attributes in case root got changed from other client */
439 if (de == de->d_sb->s_root) {
440 rc = __ll_inode_revalidate_it(de, it, MDS_INODELOCK_LOOKUP);
446 exp = ll_i2mdexp(de->d_inode);
448 OBD_FAIL_TIMEOUT(OBD_FAIL_MDC_REVALIDATE_PAUSE, 5);
449 ll_frob_intent(&it, &lookup_it);
452 if (it->it_op == IT_LOOKUP && !(de->d_flags & DCACHE_LUSTRE_INVALID))
453 GOTO(out_sa, rc = 1);
455 op_data = ll_prep_md_op_data(NULL, parent, de->d_inode,
456 de->d_name.name, de->d_name.len,
457 0, LUSTRE_OPC_ANY, NULL);
459 RETURN(PTR_ERR(op_data));
461 if ((it->it_op == IT_OPEN) && de->d_inode) {
462 struct inode *inode = de->d_inode;
463 struct ll_inode_info *lli = ll_i2info(inode);
464 struct obd_client_handle **och_p;
469 * We used to check for MDS_INODELOCK_OPEN here, but in fact
470 * just having LOOKUP lock is enough to justify inode is the
471 * same. And if inode is the same and we have suitable
472 * openhandle, then there is no point in doing another OPEN RPC
473 * just to throw away newly received openhandle. There are no
474 * security implications too, if file owner or access mode is
475 * change, LOOKUP lock is revoked.
479 if (it->it_flags & FMODE_WRITE) {
480 och_p = &lli->lli_mds_write_och;
481 och_usecount = &lli->lli_open_fd_write_count;
482 } else if (it->it_flags & FMODE_EXEC) {
483 och_p = &lli->lli_mds_exec_och;
484 och_usecount = &lli->lli_open_fd_exec_count;
486 och_p = &lli->lli_mds_read_och;
487 och_usecount = &lli->lli_open_fd_read_count;
489 /* Check for the proper lock. */
490 ibits = MDS_INODELOCK_LOOKUP;
491 if (!ll_have_md_lock(inode, &ibits, LCK_MINMODE))
493 cfs_down(&lli->lli_och_sem);
494 if (*och_p) { /* Everything is open already, do nothing */
495 /*(*och_usecount)++; Do not let them steal our open
496 handle from under us */
497 /* XXX The code above was my original idea, but in case
498 we have the handle, but we cannot use it due to later
499 checks (e.g. O_CREAT|O_EXCL flags set), nobody
500 would decrement counter increased here. So we just
501 hope the lock won't be invalidated in between. But
502 if it would be, we'll reopen the open request to
503 MDS later during file open path */
504 cfs_up(&lli->lli_och_sem);
505 ll_finish_md_op_data(op_data);
508 cfs_up(&lli->lli_och_sem);
512 if (it->it_op == IT_GETATTR)
513 first = ll_statahead_enter(parent, &de, 0);
516 it->it_create_mode &= ~cfs_curproc_umask();
517 it->it_create_mode |= M_CHECK_STALE;
518 rc = md_intent_lock(exp, op_data, NULL, 0, it,
520 &req, ll_md_blocking_ast, 0);
521 it->it_create_mode &= ~M_CHECK_STALE;
522 ll_finish_md_op_data(op_data);
523 if (it->it_op == IT_GETATTR && !first)
524 /* If there are too many locks on client-side, then some
525 * locks taken by statahead maybe dropped automatically
526 * before the real "revalidate" using them. */
527 ll_statahead_exit(parent, de, req == NULL ? rc : 0);
528 else if (first == -EEXIST)
529 ll_statahead_mark(parent, de);
531 /* If req is NULL, then md_intent_lock only tried to do a lock match;
532 * if all was well, it will return 1 if it found locks, 0 otherwise. */
533 if (req == NULL && rc >= 0) {
541 CDEBUG(D_INFO, "ll_intent_lock: rc %d : it->it_status "
542 "%d\n", rc, it->d.lustre.it_status);
548 rc = ll_revalidate_it_finish(req, it, de);
550 if (rc != -ESTALE && rc != -ENOENT)
551 ll_intent_release(it);
555 if ((it->it_op & IT_OPEN) && de->d_inode &&
556 !S_ISREG(de->d_inode->i_mode) &&
557 !S_ISDIR(de->d_inode->i_mode)) {
558 ll_release_openhandle(de, it);
562 /* unfortunately ll_intent_lock may cause a callback and revoke our
564 cfs_spin_lock(&ll_lookup_lock);
565 spin_lock(&dcache_lock);
569 d_rehash_cond(de, 0);
570 spin_unlock(&dcache_lock);
571 cfs_spin_unlock(&ll_lookup_lock);
574 /* We do not free request as it may be reused during following lookup
575 * (see comment in mdc/mdc_locks.c::mdc_intent_lock()), request will
576 * be freed in ll_lookup_it or in ll_intent_release. But if
577 * request was not completed, we need to free it. (bug 5154, 9903) */
578 if (req != NULL && !it_disposition(it, DISP_ENQ_COMPLETE))
579 ptlrpc_req_finished(req);
581 ll_unhash_aliases(de->d_inode);
582 /* done in ll_unhash_aliases()
583 dentry->d_flags |= DCACHE_LUSTRE_INVALID; */
585 CDEBUG(D_DENTRY, "revalidated dentry %.*s (%p) parent %p "
586 "inode %p refc %d\n", de->d_name.len,
587 de->d_name.name, de, de->d_parent, de->d_inode,
588 atomic_read(&de->d_count));
589 if (de->d_flags & DCACHE_LUSTRE_INVALID) {
591 de->d_flags &= ~DCACHE_LUSTRE_INVALID;
594 ll_lookup_finish_locks(it, de);
599 * This part is here to combat evil-evil race in real_lookup on 2.6
600 * kernels. The race details are: We enter do_lookup() looking for some
601 * name, there is nothing in dcache for this name yet and d_lookup()
602 * returns NULL. We proceed to real_lookup(), and while we do this,
603 * another process does open on the same file we looking up (most simple
604 * reproducer), open succeeds and the dentry is added. Now back to
605 * us. In real_lookup() we do d_lookup() again and suddenly find the
606 * dentry, so we call d_revalidate on it, but there is no lock, so
607 * without this code we would return 0, but unpatched real_lookup just
608 * returns -ENOENT in such a case instead of retrying the lookup. Once
609 * this is dealt with in real_lookup(), all of this ugly mess can go and
610 * we can just check locks in ->d_revalidate without doing any RPCs
614 if (it != &lookup_it) {
615 /* MDS_INODELOCK_UPDATE needed for IT_GETATTR case. */
616 if (it->it_op == IT_GETATTR)
617 lookup_it.it_op = IT_GETATTR;
618 ll_lookup_finish_locks(it, de);
622 /* Do real lookup here. */
623 op_data = ll_prep_md_op_data(NULL, parent, NULL, de->d_name.name,
624 de->d_name.len, 0, (it->it_op & IT_CREAT ?
626 LUSTRE_OPC_ANY), NULL);
628 RETURN(PTR_ERR(op_data));
630 rc = md_intent_lock(exp, op_data, NULL, 0, it, 0, &req,
631 ll_md_blocking_ast, 0);
633 struct mdt_body *mdt_body;
634 struct lu_fid fid = {.f_seq = 0, .f_oid = 0, .f_ver = 0};
635 mdt_body = req_capsule_server_get(&req->rq_pill, &RMF_MDT_BODY);
638 fid = *ll_inode2fid(de->d_inode);
640 /* see if we got same inode, if not - return error */
641 if (lu_fid_eq(&fid, &mdt_body->fid1)) {
642 ll_finish_md_op_data(op_data);
644 goto revalidate_finish;
646 ll_intent_release(it);
648 ll_finish_md_op_data(op_data);
653 * For rc == 1 case, should not return directly to prevent losing
654 * statahead windows; for rc == 0 case, the "lookup" will be done later.
656 if (it && it->it_op == IT_GETATTR && rc == 1) {
657 first = ll_statahead_enter(parent, &de, 0);
659 ll_statahead_exit(parent, de, 1);
660 else if (first == -EEXIST)
661 ll_statahead_mark(parent, de);
667 int ll_revalidate_nd(struct dentry *dentry, struct nameidata *nd)
672 if (nd && !(nd->flags & (LOOKUP_CONTINUE|LOOKUP_PARENT))) {
673 struct lookup_intent *it;
675 it = ll_convert_intent(&nd->intent.open, nd->flags);
679 if (it->it_op == (IT_OPEN|IT_CREAT) &&
680 nd->intent.open.flags & O_EXCL) {
681 CDEBUG(D_VFSTRACE, "create O_EXCL, returning 0\n");
686 rc = ll_revalidate_it(dentry, nd->flags, it);
688 if (rc && (nd->flags & LOOKUP_OPEN) &&
689 it_disposition(it, DISP_OPEN_OPEN)) {/*Open*/
690 #ifdef HAVE_FILE_IN_STRUCT_INTENT
691 // XXX Code duplication with ll_lookup_nd
692 if (S_ISFIFO(dentry->d_inode->i_mode)) {
693 // We cannot call open here as it would
696 (struct ptlrpc_request *)
697 it->d.lustre.it_data);
699 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,17))
700 /* 2.6.1[456] have a bug in open_namei() that forgets to check
701 * nd->intent.open.file for error, so we need to return it as lookup's result
705 nd->intent.open.file->private_data = it;
706 filp = lookup_instantiate_filp(nd, dentry,NULL);
711 nd->intent.open.file->private_data = it;
712 (void)lookup_instantiate_filp(nd, dentry,NULL);
716 ll_release_openhandle(dentry, it);
717 #endif /* HAVE_FILE_IN_STRUCT_INTENT */
719 if (!rc && (nd->flags & LOOKUP_CREATE) &&
720 it_disposition(it, DISP_OPEN_CREATE)) {
721 /* We created something but we may only return
722 * negative dentry here, so save request in dentry,
723 * if lookup will be called later on, it will
724 * pick the request, otherwise it would be freed
726 ll_d2d(dentry)->lld_it = it;
727 it = NULL; /* avoid freeing */
732 ll_intent_release(it);
733 OBD_FREE(it, sizeof(*it));
736 rc = ll_revalidate_it(dentry, 0, NULL);
742 void ll_d_iput(struct dentry *de, struct inode *inode)
745 if (!find_cbdata(inode))
750 struct dentry_operations ll_d_ops = {
751 .d_revalidate = ll_revalidate_nd,
752 .d_release = ll_release,
753 .d_delete = ll_ddelete,
755 .d_compare = ll_dcompare,