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.
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/smp_lock.h>
40 #include <linux/quotaops.h>
42 #define DEBUG_SUBSYSTEM S_LLITE
44 #include <obd_support.h>
45 #include <lustre_lite.h>
46 #include <lustre/lustre_idl.h>
47 #include <lustre_dlm.h>
48 #include <lustre_mdc.h>
49 //#include <lustre_ver.h>
50 //#include <lustre_version.h>
52 #include "llite_internal.h"
54 cfs_spinlock_t ll_lookup_lock = CFS_SPIN_LOCK_UNLOCKED;
56 /* should NOT be called with the dcache lock, see fs/dcache.c */
57 static void ll_release(struct dentry *de)
59 struct ll_dentry_data *lld;
63 if (lld == NULL) { /* NFS copies the de->d_op methods (bug 4655) */
68 ll_intent_release(lld->lld_it);
69 OBD_FREE(lld->lld_it, sizeof(*lld->lld_it));
71 LASSERT(lld->lld_cwd_count == 0);
72 LASSERT(lld->lld_mnt_count == 0);
73 OBD_FREE(de->d_fsdata, sizeof(*lld));
78 /* Compare if two dentries are the same. Don't match if the existing dentry
79 * is marked DCACHE_LUSTRE_INVALID. Returns 1 if different, 0 if the same.
81 * This avoids a race where ll_lookup_it() instantiates a dentry, but we get
82 * an AST before calling d_revalidate_it(). The dentry still exists (marked
83 * INVALID) so d_lookup() matches it, but we have no lock on it (so
84 * lock_match() fails) and we spin around real_lookup(). */
85 int ll_dcompare(struct dentry *parent, struct qstr *d_name, struct qstr *name)
87 struct dentry *dchild;
90 if (d_name->len != name->len)
93 if (memcmp(d_name->name, name->name, name->len))
96 /* XXX: d_name must be in-dentry structure */
97 dchild = container_of(d_name, struct dentry, d_name); /* ugh */
99 CDEBUG(D_DENTRY,"found name %.*s(%p) - flags %d/%x - refc %d\n",
100 name->len, name->name, dchild,
101 d_mountpoint(dchild), dchild->d_flags & DCACHE_LUSTRE_INVALID,
102 atomic_read(&dchild->d_count));
104 /* mountpoint is always valid */
105 if (d_mountpoint(dchild))
108 if (dchild->d_flags & DCACHE_LUSTRE_INVALID)
114 static inline int return_if_equal(struct ldlm_lock *lock, void *data)
116 if (lock->l_flags & LDLM_FL_CANCELING)
117 return LDLM_ITER_CONTINUE;
118 return LDLM_ITER_STOP;
121 /* find any ldlm lock of the inode in mdc and lov
125 static int find_cbdata(struct inode *inode)
127 struct ll_inode_info *lli = ll_i2info(inode);
128 struct ll_sb_info *sbi = ll_i2sbi(inode);
133 rc = md_find_cbdata(sbi->ll_md_exp, ll_inode2fid(inode),
134 return_if_equal, NULL);
139 rc = obd_find_cbdata(sbi->ll_dt_exp, lli->lli_smd,
140 return_if_equal, NULL);
146 * Called when last reference to a dentry is dropped and dcache wants to know
147 * whether or not it should cache it:
148 * - return 1 to delete the dentry immediately
149 * - return 0 to cache the dentry
150 * Should NOT be called with the dcache lock, see fs/dcache.c
152 static int ll_ddelete(struct dentry *de)
157 CDEBUG(D_DENTRY, "%s dentry %.*s (%p, parent %p, inode %p) %s%s\n",
158 (de->d_flags & DCACHE_LUSTRE_INVALID ? "deleting" : "keeping"),
159 de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
160 d_unhashed(de) ? "" : "hashed,",
161 list_empty(&de->d_subdirs) ? "" : "subdirs");
163 /* if not ldlm lock for this inode, set i_nlink to 0 so that
164 * this inode can be recycled later b=20433 */
165 LASSERT(atomic_read(&de->d_count) == 0);
166 if (de->d_inode && !find_cbdata(de->d_inode))
167 de->d_inode->i_nlink = 0;
169 if (de->d_flags & DCACHE_LUSTRE_INVALID)
175 static int ll_set_dd(struct dentry *de)
180 CDEBUG(D_DENTRY, "ldd on dentry %.*s (%p) parent %p inode %p refc %d\n",
181 de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
182 atomic_read(&de->d_count));
184 if (de->d_fsdata == NULL) {
185 struct ll_dentry_data *lld;
188 if (likely(lld != NULL)) {
190 if (likely(de->d_fsdata == NULL))
203 int ll_dops_init(struct dentry *de, int block, int init_sa)
205 struct ll_dentry_data *lld = ll_d2d(de);
208 if (lld == NULL && block != 0) {
216 if (lld != NULL && init_sa != 0)
217 lld->lld_sa_generation = 0;
219 de->d_op = &ll_d_ops;
223 void ll_intent_drop_lock(struct lookup_intent *it)
225 struct lustre_handle *handle;
227 if (it->it_op && it->d.lustre.it_lock_mode) {
228 handle = (struct lustre_handle *)&it->d.lustre.it_lock_handle;
229 CDEBUG(D_DLMTRACE, "releasing lock with cookie "LPX64
230 " from it %p\n", handle->cookie, it);
231 ldlm_lock_decref(handle, it->d.lustre.it_lock_mode);
233 /* bug 494: intent_release may be called multiple times, from
234 * this thread and we don't want to double-decref this lock */
235 it->d.lustre.it_lock_mode = 0;
239 void ll_intent_release(struct lookup_intent *it)
243 CDEBUG(D_INFO, "intent %p released\n", it);
244 ll_intent_drop_lock(it);
245 /* We are still holding extra reference on a request, need to free it */
246 if (it_disposition(it, DISP_ENQ_OPEN_REF))
247 ptlrpc_req_finished(it->d.lustre.it_data); /* ll_file_open */
248 if (it_disposition(it, DISP_ENQ_CREATE_REF)) /* create rec */
249 ptlrpc_req_finished(it->d.lustre.it_data);
250 if (it_disposition(it, DISP_ENQ_COMPLETE)) /* saved req from revalidate
252 ptlrpc_req_finished(it->d.lustre.it_data);
254 it->d.lustre.it_disposition = 0;
255 it->d.lustre.it_data = NULL;
259 /* Drop dentry if it is not used already, unhash otherwise.
260 Should be called with dcache lock held!
261 Returns: 1 if dentry was dropped, 0 if unhashed. */
262 int ll_drop_dentry(struct dentry *dentry)
265 if (atomic_read(&dentry->d_count) == 0) {
266 CDEBUG(D_DENTRY, "deleting dentry %.*s (%p) parent %p "
267 "inode %p\n", dentry->d_name.len,
268 dentry->d_name.name, dentry, dentry->d_parent,
272 unlock_dentry(dentry);
273 spin_unlock(&dcache_lock);
274 cfs_spin_unlock(&ll_lookup_lock);
276 cfs_spin_lock(&ll_lookup_lock);
277 spin_lock(&dcache_lock);
280 /* disconected dentry can not be find without lookup, because we
281 * not need his to unhash or mark invalid. */
282 if (dentry->d_flags & DCACHE_DISCONNECTED) {
283 unlock_dentry(dentry);
287 if (!(dentry->d_flags & DCACHE_LUSTRE_INVALID)) {
288 CDEBUG(D_DENTRY, "unhashing dentry %.*s (%p) parent %p "
289 "inode %p refc %d\n", dentry->d_name.len,
290 dentry->d_name.name, dentry, dentry->d_parent,
291 dentry->d_inode, atomic_read(&dentry->d_count));
292 /* actually we don't unhash the dentry, rather just
293 * mark it inaccessible for to __d_lookup(). otherwise
294 * sys_getcwd() could return -ENOENT -bzzz */
295 dentry->d_flags |= DCACHE_LUSTRE_INVALID;
296 if (!dentry->d_inode || !S_ISDIR(dentry->d_inode->i_mode))
299 unlock_dentry(dentry);
303 void ll_unhash_aliases(struct inode *inode)
305 struct list_head *tmp, *head;
309 CERROR("unexpected NULL inode, tell phil\n");
313 CDEBUG(D_INODE, "marking dentries for ino %lu/%u(%p) invalid\n",
314 inode->i_ino, inode->i_generation, inode);
316 head = &inode->i_dentry;
317 cfs_spin_lock(&ll_lookup_lock);
318 spin_lock(&dcache_lock);
321 while ((tmp = tmp->next) != head) {
322 struct dentry *dentry = list_entry(tmp, struct dentry, d_alias);
324 CDEBUG(D_DENTRY, "dentry in drop %.*s (%p) parent %p "
325 "inode %p flags %d\n", dentry->d_name.len,
326 dentry->d_name.name, dentry, dentry->d_parent,
327 dentry->d_inode, dentry->d_flags);
329 if (dentry->d_name.len == 1 && dentry->d_name.name[0] == '/') {
330 CERROR("called on root (?) dentry=%p, inode=%p "
331 "ino=%lu\n", dentry, inode, inode->i_ino);
332 lustre_dump_dentry(dentry, 1);
333 libcfs_debug_dumpstack(NULL);
336 if (ll_drop_dentry(dentry))
339 spin_unlock(&dcache_lock);
340 cfs_spin_unlock(&ll_lookup_lock);
345 int ll_revalidate_it_finish(struct ptlrpc_request *request,
346 struct lookup_intent *it,
355 if (it_disposition(it, DISP_LOOKUP_NEG))
358 rc = ll_prep_inode(&de->d_inode, request, NULL);
363 void ll_lookup_finish_locks(struct lookup_intent *it, struct dentry *dentry)
366 LASSERT(dentry != NULL);
368 if (it->d.lustre.it_lock_mode && dentry->d_inode != NULL) {
369 struct inode *inode = dentry->d_inode;
370 struct ll_sb_info *sbi = ll_i2sbi(dentry->d_inode);
372 CDEBUG(D_DLMTRACE, "setting l_data to inode %p (%lu/%u)\n",
373 inode, inode->i_ino, inode->i_generation);
374 md_set_lock_data(sbi->ll_md_exp, &it->d.lustre.it_lock_handle,
378 /* drop lookup or getattr locks immediately */
379 if (it->it_op == IT_LOOKUP || it->it_op == IT_GETATTR) {
380 /* on 2.6 there are situation when several lookups and
381 * revalidations may be requested during single operation.
382 * therefore, we don't release intent here -bzzz */
383 ll_intent_drop_lock(it);
387 void ll_frob_intent(struct lookup_intent **itp, struct lookup_intent *deft)
389 struct lookup_intent *it = *itp;
391 if (!it || it->it_op == IT_GETXATTR)
396 int ll_revalidate_it(struct dentry *de, int lookup_flags,
397 struct lookup_intent *it)
399 struct md_op_data *op_data;
400 struct ptlrpc_request *req = NULL;
401 struct lookup_intent lookup_it = { .it_op = IT_LOOKUP };
402 struct obd_export *exp;
403 struct inode *parent = de->d_parent->d_inode;
407 CDEBUG(D_VFSTRACE, "VFS Op:name=%s,intent=%s\n", de->d_name.name,
410 if (de->d_inode == NULL) {
411 /* We can only use negative dentries if this is stat or lookup,
412 for opens and stuff we do need to query server. */
413 /* If there is IT_CREAT in intent op set, then we must throw
414 away this negative dentry and actually do the request to
415 kernel to create whatever needs to be created (if possible)*/
416 if (it && (it->it_op & IT_CREAT))
419 if (de->d_flags & DCACHE_LUSTRE_INVALID)
422 rc = ll_have_md_lock(parent, MDS_INODELOCK_UPDATE, LCK_MINMODE);
426 /* Never execute intents for mount points.
427 * Attributes will be fixed up in ll_inode_revalidate_it */
428 if (d_mountpoint(de))
429 GOTO(out_sa, rc = 1);
431 /* need to get attributes in case root got changed from other client */
432 if (de == de->d_sb->s_root) {
433 rc = __ll_inode_revalidate_it(de, it, MDS_INODELOCK_LOOKUP);
439 exp = ll_i2mdexp(de->d_inode);
441 OBD_FAIL_TIMEOUT(OBD_FAIL_MDC_REVALIDATE_PAUSE, 5);
442 ll_frob_intent(&it, &lookup_it);
445 if (it->it_op == IT_LOOKUP && !(de->d_flags & DCACHE_LUSTRE_INVALID))
446 GOTO(out_sa, rc = 1);
448 op_data = ll_prep_md_op_data(NULL, parent, de->d_inode,
449 de->d_name.name, de->d_name.len,
450 0, LUSTRE_OPC_ANY, NULL);
452 RETURN(PTR_ERR(op_data));
454 if ((it->it_op == IT_OPEN) && de->d_inode) {
455 struct inode *inode = de->d_inode;
456 struct ll_inode_info *lli = ll_i2info(inode);
457 struct obd_client_handle **och_p;
461 * We used to check for MDS_INODELOCK_OPEN here, but in fact
462 * just having LOOKUP lock is enough to justify inode is the
463 * same. And if inode is the same and we have suitable
464 * openhandle, then there is no point in doing another OPEN RPC
465 * just to throw away newly received openhandle. There are no
466 * security implications too, if file owner or access mode is
467 * change, LOOKUP lock is revoked.
471 if (it->it_flags & FMODE_WRITE) {
472 och_p = &lli->lli_mds_write_och;
473 och_usecount = &lli->lli_open_fd_write_count;
474 } else if (it->it_flags & FMODE_EXEC) {
475 och_p = &lli->lli_mds_exec_och;
476 och_usecount = &lli->lli_open_fd_exec_count;
478 och_p = &lli->lli_mds_read_och;
479 och_usecount = &lli->lli_open_fd_read_count;
481 /* Check for the proper lock. */
482 if (!ll_have_md_lock(inode, MDS_INODELOCK_LOOKUP, LCK_MINMODE))
484 cfs_down(&lli->lli_och_sem);
485 if (*och_p) { /* Everything is open already, do nothing */
486 /*(*och_usecount)++; Do not let them steal our open
487 handle from under us */
488 /* XXX The code above was my original idea, but in case
489 we have the handle, but we cannot use it due to later
490 checks (e.g. O_CREAT|O_EXCL flags set), nobody
491 would decrement counter increased here. So we just
492 hope the lock won't be invalidated in between. But
493 if it would be, we'll reopen the open request to
494 MDS later during file open path */
495 cfs_up(&lli->lli_och_sem);
496 ll_finish_md_op_data(op_data);
499 cfs_up(&lli->lli_och_sem);
503 if (it->it_op == IT_GETATTR)
504 first = ll_statahead_enter(parent, &de, 0);
507 it->it_create_mode &= ~cfs_curproc_umask();
508 it->it_create_mode |= M_CHECK_STALE;
509 rc = md_intent_lock(exp, op_data, NULL, 0, it,
511 &req, ll_md_blocking_ast, 0);
512 it->it_create_mode &= ~M_CHECK_STALE;
513 ll_finish_md_op_data(op_data);
514 if (it->it_op == IT_GETATTR && !first)
515 /* If there are too many locks on client-side, then some
516 * locks taken by statahead maybe dropped automatically
517 * before the real "revalidate" using them. */
518 ll_statahead_exit(parent, de, req == NULL ? rc : 0);
519 else if (first == -EEXIST)
520 ll_statahead_mark(parent, de);
522 /* If req is NULL, then md_intent_lock only tried to do a lock match;
523 * if all was well, it will return 1 if it found locks, 0 otherwise. */
524 if (req == NULL && rc >= 0) {
532 CDEBUG(D_INFO, "ll_intent_lock: rc %d : it->it_status "
533 "%d\n", rc, it->d.lustre.it_status);
539 rc = ll_revalidate_it_finish(req, it, de);
541 if (rc != -ESTALE && rc != -ENOENT)
542 ll_intent_release(it);
546 if ((it->it_op & IT_OPEN) && de->d_inode &&
547 !S_ISREG(de->d_inode->i_mode) &&
548 !S_ISDIR(de->d_inode->i_mode)) {
549 ll_release_openhandle(de, it);
553 /* unfortunately ll_intent_lock may cause a callback and revoke our
555 cfs_spin_lock(&ll_lookup_lock);
556 spin_lock(&dcache_lock);
560 d_rehash_cond(de, 0);
561 spin_unlock(&dcache_lock);
562 cfs_spin_unlock(&ll_lookup_lock);
565 /* We do not free request as it may be reused during following lookup
566 * (see comment in mdc/mdc_locks.c::mdc_intent_lock()), request will
567 * be freed in ll_lookup_it or in ll_intent_release. But if
568 * request was not completed, we need to free it. (bug 5154, 9903) */
569 if (req != NULL && !it_disposition(it, DISP_ENQ_COMPLETE))
570 ptlrpc_req_finished(req);
572 ll_unhash_aliases(de->d_inode);
573 /* done in ll_unhash_aliases()
574 dentry->d_flags |= DCACHE_LUSTRE_INVALID; */
576 CDEBUG(D_DENTRY, "revalidated dentry %.*s (%p) parent %p "
577 "inode %p refc %d\n", de->d_name.len,
578 de->d_name.name, de, de->d_parent, de->d_inode,
579 atomic_read(&de->d_count));
580 if (de->d_flags & DCACHE_LUSTRE_INVALID) {
582 de->d_flags &= ~DCACHE_LUSTRE_INVALID;
585 ll_lookup_finish_locks(it, de);
590 * This part is here to combat evil-evil race in real_lookup on 2.6
591 * kernels. The race details are: We enter do_lookup() looking for some
592 * name, there is nothing in dcache for this name yet and d_lookup()
593 * returns NULL. We proceed to real_lookup(), and while we do this,
594 * another process does open on the same file we looking up (most simple
595 * reproducer), open succeeds and the dentry is added. Now back to
596 * us. In real_lookup() we do d_lookup() again and suddenly find the
597 * dentry, so we call d_revalidate on it, but there is no lock, so
598 * without this code we would return 0, but unpatched real_lookup just
599 * returns -ENOENT in such a case instead of retrying the lookup. Once
600 * this is dealt with in real_lookup(), all of this ugly mess can go and
601 * we can just check locks in ->d_revalidate without doing any RPCs
605 if (it != &lookup_it) {
606 /* MDS_INODELOCK_UPDATE needed for IT_GETATTR case. */
607 if (it->it_op == IT_GETATTR)
608 lookup_it.it_op = IT_GETATTR;
609 ll_lookup_finish_locks(it, de);
613 /* Do real lookup here. */
614 op_data = ll_prep_md_op_data(NULL, parent, NULL, de->d_name.name,
615 de->d_name.len, 0, (it->it_op & IT_CREAT ?
617 LUSTRE_OPC_ANY), NULL);
619 RETURN(PTR_ERR(op_data));
621 rc = md_intent_lock(exp, op_data, NULL, 0, it, 0, &req,
622 ll_md_blocking_ast, 0);
624 struct mdt_body *mdt_body;
625 struct lu_fid fid = {.f_seq = 0, .f_oid = 0, .f_ver = 0};
626 mdt_body = req_capsule_server_get(&req->rq_pill, &RMF_MDT_BODY);
629 fid = *ll_inode2fid(de->d_inode);
631 /* see if we got same inode, if not - return error */
632 if (lu_fid_eq(&fid, &mdt_body->fid1)) {
633 ll_finish_md_op_data(op_data);
635 goto revalidate_finish;
637 ll_intent_release(it);
639 ll_finish_md_op_data(op_data);
644 * For rc == 1 case, should not return directly to prevent losing
645 * statahead windows; for rc == 0 case, the "lookup" will be done later.
647 if (it && it->it_op == IT_GETATTR && rc == 1) {
648 first = ll_statahead_enter(parent, &de, 0);
650 ll_statahead_exit(parent, de, 1);
651 else if (first == -EEXIST)
652 ll_statahead_mark(parent, de);
658 int ll_revalidate_nd(struct dentry *dentry, struct nameidata *nd)
663 if (nd && !(nd->flags & (LOOKUP_CONTINUE|LOOKUP_PARENT))) {
664 struct lookup_intent *it;
666 it = ll_convert_intent(&nd->intent.open, nd->flags);
670 if (it->it_op == (IT_OPEN|IT_CREAT) &&
671 nd->intent.open.flags & O_EXCL) {
672 CDEBUG(D_VFSTRACE, "create O_EXCL, returning 0\n");
677 rc = ll_revalidate_it(dentry, nd->flags, it);
679 if (rc && (nd->flags & LOOKUP_OPEN) &&
680 it_disposition(it, DISP_OPEN_OPEN)) {/*Open*/
681 #ifdef HAVE_FILE_IN_STRUCT_INTENT
682 // XXX Code duplication with ll_lookup_nd
683 if (S_ISFIFO(dentry->d_inode->i_mode)) {
684 // We cannot call open here as it would
687 (struct ptlrpc_request *)
688 it->d.lustre.it_data);
690 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,17))
691 /* 2.6.1[456] have a bug in open_namei() that forgets to check
692 * nd->intent.open.file for error, so we need to return it as lookup's result
696 nd->intent.open.file->private_data = it;
697 filp = lookup_instantiate_filp(nd, dentry,NULL);
702 nd->intent.open.file->private_data = it;
703 (void)lookup_instantiate_filp(nd, dentry,NULL);
707 ll_release_openhandle(dentry, it);
708 #endif /* HAVE_FILE_IN_STRUCT_INTENT */
710 if (!rc && (nd->flags & LOOKUP_CREATE) &&
711 it_disposition(it, DISP_OPEN_CREATE)) {
712 /* We created something but we may only return
713 * negative dentry here, so save request in dentry,
714 * if lookup will be called later on, it will
715 * pick the request, otherwise it would be freed
717 ll_d2d(dentry)->lld_it = it;
718 it = NULL; /* avoid freeing */
723 ll_intent_release(it);
724 OBD_FREE(it, sizeof(*it));
727 rc = ll_revalidate_it(dentry, 0, NULL);
733 void ll_d_iput(struct dentry *de, struct inode *inode)
736 if (!find_cbdata(inode))
741 struct dentry_operations ll_d_ops = {
742 .d_revalidate = ll_revalidate_nd,
743 .d_release = ll_release,
744 .d_delete = ll_ddelete,
746 .d_compare = ll_dcompare,