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_mdc.h>
52 //#include <lustre_ver.h>
53 //#include <lustre_version.h>
55 #include "llite_internal.h"
57 cfs_spinlock_t ll_lookup_lock = CFS_SPIN_LOCK_UNLOCKED;
59 /* should NOT be called with the dcache lock, see fs/dcache.c */
60 static void ll_release(struct dentry *de)
62 struct ll_dentry_data *lld;
66 if (lld == NULL) { /* NFS copies the de->d_op methods (bug 4655) */
71 ll_intent_release(lld->lld_it);
72 OBD_FREE(lld->lld_it, sizeof(*lld->lld_it));
74 LASSERT(lld->lld_cwd_count == 0);
75 LASSERT(lld->lld_mnt_count == 0);
76 OBD_FREE(de->d_fsdata, sizeof(*lld));
81 /* Compare if two dentries are the same. Don't match if the existing dentry
82 * is marked DCACHE_LUSTRE_INVALID. Returns 1 if different, 0 if the same.
84 * This avoids a race where ll_lookup_it() instantiates a dentry, but we get
85 * an AST before calling d_revalidate_it(). The dentry still exists (marked
86 * INVALID) so d_lookup() matches it, but we have no lock on it (so
87 * lock_match() fails) and we spin around real_lookup(). */
88 int ll_dcompare(struct dentry *parent, struct qstr *d_name, struct qstr *name)
90 struct dentry *dchild;
93 if (d_name->len != name->len)
96 if (memcmp(d_name->name, name->name, name->len))
99 /* XXX: d_name must be in-dentry structure */
100 dchild = container_of(d_name, struct dentry, d_name); /* ugh */
102 CDEBUG(D_DENTRY,"found name %.*s(%p) - flags %d/%x - refc %d\n",
103 name->len, name->name, dchild,
104 d_mountpoint(dchild), dchild->d_flags & DCACHE_LUSTRE_INVALID,
105 atomic_read(&dchild->d_count));
107 /* mountpoint is always valid */
108 if (d_mountpoint(dchild))
111 if (dchild->d_flags & DCACHE_LUSTRE_INVALID)
117 static inline int return_if_equal(struct ldlm_lock *lock, void *data)
119 if (lock->l_flags & LDLM_FL_CANCELING)
120 return LDLM_ITER_CONTINUE;
121 return LDLM_ITER_STOP;
124 /* find any ldlm lock of the inode in mdc and lov
128 static int find_cbdata(struct inode *inode)
130 struct ll_inode_info *lli = ll_i2info(inode);
131 struct ll_sb_info *sbi = ll_i2sbi(inode);
136 rc = md_find_cbdata(sbi->ll_md_exp, ll_inode2fid(inode),
137 return_if_equal, NULL);
142 rc = obd_find_cbdata(sbi->ll_dt_exp, lli->lli_smd,
143 return_if_equal, NULL);
149 * Called when last reference to a dentry is dropped and dcache wants to know
150 * whether or not it should cache it:
151 * - return 1 to delete the dentry immediately
152 * - return 0 to cache the dentry
153 * Should NOT be called with the dcache lock, see fs/dcache.c
155 static int ll_ddelete(struct dentry *de)
160 CDEBUG(D_DENTRY, "%s dentry %.*s (%p, parent %p, inode %p) %s%s\n",
161 (de->d_flags & DCACHE_LUSTRE_INVALID ? "deleting" : "keeping"),
162 de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
163 d_unhashed(de) ? "" : "hashed,",
164 list_empty(&de->d_subdirs) ? "" : "subdirs");
166 /* if not ldlm lock for this inode, set i_nlink to 0 so that
167 * this inode can be recycled later b=20433 */
168 LASSERT(atomic_read(&de->d_count) == 0);
169 if (de->d_inode && !find_cbdata(de->d_inode))
170 de->d_inode->i_nlink = 0;
172 if (de->d_flags & DCACHE_LUSTRE_INVALID)
178 static int ll_set_dd(struct dentry *de)
183 CDEBUG(D_DENTRY, "ldd on dentry %.*s (%p) parent %p inode %p refc %d\n",
184 de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
185 atomic_read(&de->d_count));
187 if (de->d_fsdata == NULL) {
188 struct ll_dentry_data *lld;
191 if (likely(lld != NULL)) {
193 if (likely(de->d_fsdata == NULL))
206 int ll_dops_init(struct dentry *de, int block, int init_sa)
208 struct ll_dentry_data *lld = ll_d2d(de);
211 if (lld == NULL && block != 0) {
219 if (lld != NULL && init_sa != 0)
220 lld->lld_sa_generation = 0;
222 de->d_op = &ll_d_ops;
226 void ll_intent_drop_lock(struct lookup_intent *it)
228 struct lustre_handle *handle;
230 if (it->it_op && it->d.lustre.it_lock_mode) {
231 handle = (struct lustre_handle *)&it->d.lustre.it_lock_handle;
232 CDEBUG(D_DLMTRACE, "releasing lock with cookie "LPX64
233 " from it %p\n", handle->cookie, it);
234 ldlm_lock_decref(handle, it->d.lustre.it_lock_mode);
236 /* bug 494: intent_release may be called multiple times, from
237 * this thread and we don't want to double-decref this lock */
238 it->d.lustre.it_lock_mode = 0;
242 void ll_intent_release(struct lookup_intent *it)
246 CDEBUG(D_INFO, "intent %p released\n", it);
247 ll_intent_drop_lock(it);
248 /* We are still holding extra reference on a request, need to free it */
249 if (it_disposition(it, DISP_ENQ_OPEN_REF))
250 ptlrpc_req_finished(it->d.lustre.it_data); /* ll_file_open */
251 if (it_disposition(it, DISP_ENQ_CREATE_REF)) /* create rec */
252 ptlrpc_req_finished(it->d.lustre.it_data);
253 if (it_disposition(it, DISP_ENQ_COMPLETE)) /* saved req from revalidate
255 ptlrpc_req_finished(it->d.lustre.it_data);
257 it->d.lustre.it_disposition = 0;
258 it->d.lustre.it_data = NULL;
262 /* Drop dentry if it is not used already, unhash otherwise.
263 Should be called with dcache lock held!
264 Returns: 1 if dentry was dropped, 0 if unhashed. */
265 int ll_drop_dentry(struct dentry *dentry)
268 if (atomic_read(&dentry->d_count) == 0) {
269 CDEBUG(D_DENTRY, "deleting dentry %.*s (%p) parent %p "
270 "inode %p\n", dentry->d_name.len,
271 dentry->d_name.name, dentry, dentry->d_parent,
275 unlock_dentry(dentry);
276 spin_unlock(&dcache_lock);
277 cfs_spin_unlock(&ll_lookup_lock);
279 cfs_spin_lock(&ll_lookup_lock);
280 spin_lock(&dcache_lock);
283 /* disconected dentry can not be find without lookup, because we
284 * not need his to unhash or mark invalid. */
285 if (dentry->d_flags & DCACHE_DISCONNECTED) {
286 unlock_dentry(dentry);
290 if (!(dentry->d_flags & DCACHE_LUSTRE_INVALID)) {
291 CDEBUG(D_DENTRY, "unhashing dentry %.*s (%p) parent %p "
292 "inode %p refc %d\n", dentry->d_name.len,
293 dentry->d_name.name, dentry, dentry->d_parent,
294 dentry->d_inode, atomic_read(&dentry->d_count));
295 /* actually we don't unhash the dentry, rather just
296 * mark it inaccessible for to __d_lookup(). otherwise
297 * sys_getcwd() could return -ENOENT -bzzz */
298 dentry->d_flags |= DCACHE_LUSTRE_INVALID;
299 if (!dentry->d_inode || !S_ISDIR(dentry->d_inode->i_mode))
302 unlock_dentry(dentry);
306 void ll_unhash_aliases(struct inode *inode)
308 struct list_head *tmp, *head;
312 CERROR("unexpected NULL inode, tell phil\n");
316 CDEBUG(D_INODE, "marking dentries for ino %lu/%u(%p) invalid\n",
317 inode->i_ino, inode->i_generation, inode);
319 head = &inode->i_dentry;
320 cfs_spin_lock(&ll_lookup_lock);
321 spin_lock(&dcache_lock);
324 while ((tmp = tmp->next) != head) {
325 struct dentry *dentry = list_entry(tmp, struct dentry, d_alias);
327 CDEBUG(D_DENTRY, "dentry in drop %.*s (%p) parent %p "
328 "inode %p flags %d\n", dentry->d_name.len,
329 dentry->d_name.name, dentry, dentry->d_parent,
330 dentry->d_inode, dentry->d_flags);
332 if (dentry->d_name.len == 1 && dentry->d_name.name[0] == '/') {
333 CERROR("called on root (?) dentry=%p, inode=%p "
334 "ino=%lu\n", dentry, inode, inode->i_ino);
335 lustre_dump_dentry(dentry, 1);
336 libcfs_debug_dumpstack(NULL);
339 if (ll_drop_dentry(dentry))
342 spin_unlock(&dcache_lock);
343 cfs_spin_unlock(&ll_lookup_lock);
348 int ll_revalidate_it_finish(struct ptlrpc_request *request,
349 struct lookup_intent *it,
358 if (it_disposition(it, DISP_LOOKUP_NEG))
361 rc = ll_prep_inode(&de->d_inode, request, NULL);
366 void ll_lookup_finish_locks(struct lookup_intent *it, struct dentry *dentry)
369 LASSERT(dentry != NULL);
371 if (it->d.lustre.it_lock_mode && dentry->d_inode != NULL) {
372 struct inode *inode = dentry->d_inode;
373 struct ll_sb_info *sbi = ll_i2sbi(dentry->d_inode);
375 CDEBUG(D_DLMTRACE, "setting l_data to inode %p (%lu/%u)\n",
376 inode, inode->i_ino, inode->i_generation);
377 md_set_lock_data(sbi->ll_md_exp, &it->d.lustre.it_lock_handle,
381 /* drop lookup or getattr locks immediately */
382 if (it->it_op == IT_LOOKUP || it->it_op == IT_GETATTR) {
383 /* on 2.6 there are situation when several lookups and
384 * revalidations may be requested during single operation.
385 * therefore, we don't release intent here -bzzz */
386 ll_intent_drop_lock(it);
390 void ll_frob_intent(struct lookup_intent **itp, struct lookup_intent *deft)
392 struct lookup_intent *it = *itp;
394 if (!it || it->it_op == IT_GETXATTR)
399 int ll_revalidate_it(struct dentry *de, int lookup_flags,
400 struct lookup_intent *it)
402 struct md_op_data *op_data;
403 struct ptlrpc_request *req = NULL;
404 struct lookup_intent lookup_it = { .it_op = IT_LOOKUP };
405 struct obd_export *exp;
406 struct inode *parent = de->d_parent->d_inode;
410 CDEBUG(D_VFSTRACE, "VFS Op:name=%s,intent=%s\n", de->d_name.name,
413 if (de->d_inode == NULL) {
414 /* We can only use negative dentries if this is stat or lookup,
415 for opens and stuff we do need to query server. */
416 /* If there is IT_CREAT in intent op set, then we must throw
417 away this negative dentry and actually do the request to
418 kernel to create whatever needs to be created (if possible)*/
419 if (it && (it->it_op & IT_CREAT))
422 if (de->d_flags & DCACHE_LUSTRE_INVALID)
425 rc = ll_have_md_lock(parent, MDS_INODELOCK_UPDATE, LCK_MINMODE);
429 /* Never execute intents for mount points.
430 * Attributes will be fixed up in ll_inode_revalidate_it */
431 if (d_mountpoint(de))
432 GOTO(out_sa, rc = 1);
434 /* need to get attributes in case root got changed from other client */
435 if (de == de->d_sb->s_root) {
436 rc = __ll_inode_revalidate_it(de, it, MDS_INODELOCK_LOOKUP);
442 exp = ll_i2mdexp(de->d_inode);
444 OBD_FAIL_TIMEOUT(OBD_FAIL_MDC_REVALIDATE_PAUSE, 5);
445 ll_frob_intent(&it, &lookup_it);
448 if (it->it_op == IT_LOOKUP && !(de->d_flags & DCACHE_LUSTRE_INVALID))
449 GOTO(out_sa, rc = 1);
451 op_data = ll_prep_md_op_data(NULL, parent, de->d_inode,
452 de->d_name.name, de->d_name.len,
453 0, LUSTRE_OPC_ANY, NULL);
455 RETURN(PTR_ERR(op_data));
457 if ((it->it_op == IT_OPEN) && de->d_inode) {
458 struct inode *inode = de->d_inode;
459 struct ll_inode_info *lli = ll_i2info(inode);
460 struct obd_client_handle **och_p;
464 * We used to check for MDS_INODELOCK_OPEN here, but in fact
465 * just having LOOKUP lock is enough to justify inode is the
466 * same. And if inode is the same and we have suitable
467 * openhandle, then there is no point in doing another OPEN RPC
468 * just to throw away newly received openhandle. There are no
469 * security implications too, if file owner or access mode is
470 * change, LOOKUP lock is revoked.
474 if (it->it_flags & FMODE_WRITE) {
475 och_p = &lli->lli_mds_write_och;
476 och_usecount = &lli->lli_open_fd_write_count;
477 } else if (it->it_flags & FMODE_EXEC) {
478 och_p = &lli->lli_mds_exec_och;
479 och_usecount = &lli->lli_open_fd_exec_count;
481 och_p = &lli->lli_mds_read_och;
482 och_usecount = &lli->lli_open_fd_read_count;
484 /* Check for the proper lock. */
485 if (!ll_have_md_lock(inode, MDS_INODELOCK_LOOKUP, LCK_MINMODE))
487 cfs_down(&lli->lli_och_sem);
488 if (*och_p) { /* Everything is open already, do nothing */
489 /*(*och_usecount)++; Do not let them steal our open
490 handle from under us */
491 /* XXX The code above was my original idea, but in case
492 we have the handle, but we cannot use it due to later
493 checks (e.g. O_CREAT|O_EXCL flags set), nobody
494 would decrement counter increased here. So we just
495 hope the lock won't be invalidated in between. But
496 if it would be, we'll reopen the open request to
497 MDS later during file open path */
498 cfs_up(&lli->lli_och_sem);
499 ll_finish_md_op_data(op_data);
502 cfs_up(&lli->lli_och_sem);
506 if (it->it_op == IT_GETATTR)
507 first = ll_statahead_enter(parent, &de, 0);
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);
517 if (it->it_op == IT_GETATTR && !first)
518 /* If there are too many locks on client-side, then some
519 * locks taken by statahead maybe dropped automatically
520 * before the real "revalidate" using them. */
521 ll_statahead_exit(parent, de, req == NULL ? rc : 0);
522 else if (first == -EEXIST)
523 ll_statahead_mark(parent, de);
525 /* If req is NULL, then md_intent_lock only tried to do a lock match;
526 * if all was well, it will return 1 if it found locks, 0 otherwise. */
527 if (req == NULL && rc >= 0) {
535 CDEBUG(D_INFO, "ll_intent_lock: rc %d : it->it_status "
536 "%d\n", rc, it->d.lustre.it_status);
542 rc = ll_revalidate_it_finish(req, it, de);
544 if (rc != -ESTALE && rc != -ENOENT)
545 ll_intent_release(it);
549 if ((it->it_op & IT_OPEN) && de->d_inode &&
550 !S_ISREG(de->d_inode->i_mode) &&
551 !S_ISDIR(de->d_inode->i_mode)) {
552 ll_release_openhandle(de, it);
556 /* unfortunately ll_intent_lock may cause a callback and revoke our
558 cfs_spin_lock(&ll_lookup_lock);
559 spin_lock(&dcache_lock);
563 d_rehash_cond(de, 0);
564 spin_unlock(&dcache_lock);
565 cfs_spin_unlock(&ll_lookup_lock);
568 /* We do not free request as it may be reused during following lookup
569 * (see comment in mdc/mdc_locks.c::mdc_intent_lock()), request will
570 * be freed in ll_lookup_it or in ll_intent_release. But if
571 * request was not completed, we need to free it. (bug 5154, 9903) */
572 if (req != NULL && !it_disposition(it, DISP_ENQ_COMPLETE))
573 ptlrpc_req_finished(req);
575 ll_unhash_aliases(de->d_inode);
576 /* done in ll_unhash_aliases()
577 dentry->d_flags |= DCACHE_LUSTRE_INVALID; */
579 CDEBUG(D_DENTRY, "revalidated dentry %.*s (%p) parent %p "
580 "inode %p refc %d\n", de->d_name.len,
581 de->d_name.name, de, de->d_parent, de->d_inode,
582 atomic_read(&de->d_count));
583 if (de->d_flags & DCACHE_LUSTRE_INVALID) {
585 de->d_flags &= ~DCACHE_LUSTRE_INVALID;
588 ll_lookup_finish_locks(it, de);
593 * This part is here to combat evil-evil race in real_lookup on 2.6
594 * kernels. The race details are: We enter do_lookup() looking for some
595 * name, there is nothing in dcache for this name yet and d_lookup()
596 * returns NULL. We proceed to real_lookup(), and while we do this,
597 * another process does open on the same file we looking up (most simple
598 * reproducer), open succeeds and the dentry is added. Now back to
599 * us. In real_lookup() we do d_lookup() again and suddenly find the
600 * dentry, so we call d_revalidate on it, but there is no lock, so
601 * without this code we would return 0, but unpatched real_lookup just
602 * returns -ENOENT in such a case instead of retrying the lookup. Once
603 * this is dealt with in real_lookup(), all of this ugly mess can go and
604 * we can just check locks in ->d_revalidate without doing any RPCs
608 if (it != &lookup_it) {
609 /* MDS_INODELOCK_UPDATE needed for IT_GETATTR case. */
610 if (it->it_op == IT_GETATTR)
611 lookup_it.it_op = IT_GETATTR;
612 ll_lookup_finish_locks(it, de);
616 /* Do real lookup here. */
617 op_data = ll_prep_md_op_data(NULL, parent, NULL, de->d_name.name,
618 de->d_name.len, 0, (it->it_op & IT_CREAT ?
620 LUSTRE_OPC_ANY), NULL);
622 RETURN(PTR_ERR(op_data));
624 rc = md_intent_lock(exp, op_data, NULL, 0, it, 0, &req,
625 ll_md_blocking_ast, 0);
627 struct mdt_body *mdt_body;
628 struct lu_fid fid = {.f_seq = 0, .f_oid = 0, .f_ver = 0};
629 mdt_body = req_capsule_server_get(&req->rq_pill, &RMF_MDT_BODY);
632 fid = *ll_inode2fid(de->d_inode);
634 /* see if we got same inode, if not - return error */
635 if (lu_fid_eq(&fid, &mdt_body->fid1)) {
636 ll_finish_md_op_data(op_data);
638 goto revalidate_finish;
640 ll_intent_release(it);
642 ll_finish_md_op_data(op_data);
647 * For rc == 1 case, should not return directly to prevent losing
648 * statahead windows; for rc == 0 case, the "lookup" will be done later.
650 if (it && it->it_op == IT_GETATTR && rc == 1) {
651 first = ll_statahead_enter(parent, &de, 0);
653 ll_statahead_exit(parent, de, 1);
654 else if (first == -EEXIST)
655 ll_statahead_mark(parent, de);
661 int ll_revalidate_nd(struct dentry *dentry, struct nameidata *nd)
666 if (nd && !(nd->flags & (LOOKUP_CONTINUE|LOOKUP_PARENT))) {
667 struct lookup_intent *it;
669 it = ll_convert_intent(&nd->intent.open, nd->flags);
673 if (it->it_op == (IT_OPEN|IT_CREAT) &&
674 nd->intent.open.flags & O_EXCL) {
675 CDEBUG(D_VFSTRACE, "create O_EXCL, returning 0\n");
680 rc = ll_revalidate_it(dentry, nd->flags, it);
682 if (rc && (nd->flags & LOOKUP_OPEN) &&
683 it_disposition(it, DISP_OPEN_OPEN)) {/*Open*/
684 #ifdef HAVE_FILE_IN_STRUCT_INTENT
685 // XXX Code duplication with ll_lookup_nd
686 if (S_ISFIFO(dentry->d_inode->i_mode)) {
687 // We cannot call open here as it would
690 (struct ptlrpc_request *)
691 it->d.lustre.it_data);
693 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,17))
694 /* 2.6.1[456] have a bug in open_namei() that forgets to check
695 * nd->intent.open.file for error, so we need to return it as lookup's result
699 nd->intent.open.file->private_data = it;
700 filp = lookup_instantiate_filp(nd, dentry,NULL);
705 nd->intent.open.file->private_data = it;
706 (void)lookup_instantiate_filp(nd, dentry,NULL);
710 ll_release_openhandle(dentry, it);
711 #endif /* HAVE_FILE_IN_STRUCT_INTENT */
713 if (!rc && (nd->flags & LOOKUP_CREATE) &&
714 it_disposition(it, DISP_OPEN_CREATE)) {
715 /* We created something but we may only return
716 * negative dentry here, so save request in dentry,
717 * if lookup will be called later on, it will
718 * pick the request, otherwise it would be freed
720 ll_d2d(dentry)->lld_it = it;
721 it = NULL; /* avoid freeing */
726 ll_intent_release(it);
727 OBD_FREE(it, sizeof(*it));
730 rc = ll_revalidate_it(dentry, 0, NULL);
736 void ll_d_iput(struct dentry *de, struct inode *inode)
739 if (!find_cbdata(inode))
744 struct dentry_operations ll_d_ops = {
745 .d_revalidate = ll_revalidate_nd,
746 .d_release = ll_release,
747 .d_delete = ll_ddelete,
749 .d_compare = ll_dcompare,