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)
120 (LDLM_FL_CANCELING | LDLM_FL_DISCARD_DATA)) ==
121 (LDLM_FL_CANCELING | LDLM_FL_DISCARD_DATA))
122 return LDLM_ITER_CONTINUE;
123 return LDLM_ITER_STOP;
126 /* find any ldlm lock of the inode in mdc and lov
130 static int find_cbdata(struct inode *inode)
132 struct ll_inode_info *lli = ll_i2info(inode);
133 struct ll_sb_info *sbi = ll_i2sbi(inode);
138 rc = md_find_cbdata(sbi->ll_md_exp, ll_inode2fid(inode),
139 return_if_equal, NULL);
144 rc = obd_find_cbdata(sbi->ll_dt_exp, lli->lli_smd,
145 return_if_equal, NULL);
151 * Called when last reference to a dentry is dropped and dcache wants to know
152 * whether or not it should cache it:
153 * - return 1 to delete the dentry immediately
154 * - return 0 to cache the dentry
155 * Should NOT be called with the dcache lock, see fs/dcache.c
157 static int ll_ddelete(struct dentry *de)
162 CDEBUG(D_DENTRY, "%s dentry %.*s (%p, parent %p, inode %p) %s%s\n",
163 (de->d_flags & DCACHE_LUSTRE_INVALID ? "deleting" : "keeping"),
164 de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
165 d_unhashed(de) ? "" : "hashed,",
166 list_empty(&de->d_subdirs) ? "" : "subdirs");
168 /* if not ldlm lock for this inode, set i_nlink to 0 so that
169 * this inode can be recycled later b=20433 */
170 LASSERT(atomic_read(&de->d_count) == 0);
171 if (de->d_inode && !find_cbdata(de->d_inode))
172 de->d_inode->i_nlink = 0;
174 if (de->d_flags & DCACHE_LUSTRE_INVALID)
180 static int ll_set_dd(struct dentry *de)
185 CDEBUG(D_DENTRY, "ldd on dentry %.*s (%p) parent %p inode %p refc %d\n",
186 de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
187 atomic_read(&de->d_count));
189 if (de->d_fsdata == NULL) {
190 struct ll_dentry_data *lld;
193 if (likely(lld != NULL)) {
195 if (likely(de->d_fsdata == NULL))
208 int ll_dops_init(struct dentry *de, int block, int init_sa)
210 struct ll_dentry_data *lld = ll_d2d(de);
213 if (lld == NULL && block != 0) {
221 if (lld != NULL && init_sa != 0)
222 lld->lld_sa_generation = 0;
224 de->d_op = &ll_d_ops;
228 void ll_intent_drop_lock(struct lookup_intent *it)
230 struct lustre_handle *handle;
232 if (it->it_op && it->d.lustre.it_lock_mode) {
233 handle = (struct lustre_handle *)&it->d.lustre.it_lock_handle;
234 CDEBUG(D_DLMTRACE, "releasing lock with cookie "LPX64
235 " from it %p\n", handle->cookie, it);
236 ldlm_lock_decref(handle, it->d.lustre.it_lock_mode);
238 /* bug 494: intent_release may be called multiple times, from
239 * this thread and we don't want to double-decref this lock */
240 it->d.lustre.it_lock_mode = 0;
244 void ll_intent_release(struct lookup_intent *it)
248 CDEBUG(D_INFO, "intent %p released\n", it);
249 ll_intent_drop_lock(it);
250 /* We are still holding extra reference on a request, need to free it */
251 if (it_disposition(it, DISP_ENQ_OPEN_REF))
252 ptlrpc_req_finished(it->d.lustre.it_data); /* ll_file_open */
253 if (it_disposition(it, DISP_ENQ_CREATE_REF)) /* create rec */
254 ptlrpc_req_finished(it->d.lustre.it_data);
255 if (it_disposition(it, DISP_ENQ_COMPLETE)) /* saved req from revalidate
257 ptlrpc_req_finished(it->d.lustre.it_data);
259 it->d.lustre.it_disposition = 0;
260 it->d.lustre.it_data = NULL;
264 /* Drop dentry if it is not used already, unhash otherwise.
265 Should be called with dcache lock held!
266 Returns: 1 if dentry was dropped, 0 if unhashed. */
267 int ll_drop_dentry(struct dentry *dentry)
270 if (atomic_read(&dentry->d_count) == 0) {
271 CDEBUG(D_DENTRY, "deleting dentry %.*s (%p) parent %p "
272 "inode %p\n", dentry->d_name.len,
273 dentry->d_name.name, dentry, dentry->d_parent,
277 unlock_dentry(dentry);
278 spin_unlock(&dcache_lock);
279 cfs_spin_unlock(&ll_lookup_lock);
281 cfs_spin_lock(&ll_lookup_lock);
282 spin_lock(&dcache_lock);
285 /* disconected dentry can not be find without lookup, because we
286 * not need his to unhash or mark invalid. */
287 if (dentry->d_flags & DCACHE_DISCONNECTED) {
288 unlock_dentry(dentry);
292 if (!(dentry->d_flags & DCACHE_LUSTRE_INVALID)) {
293 CDEBUG(D_DENTRY, "unhashing dentry %.*s (%p) parent %p "
294 "inode %p refc %d\n", dentry->d_name.len,
295 dentry->d_name.name, dentry, dentry->d_parent,
296 dentry->d_inode, atomic_read(&dentry->d_count));
297 /* actually we don't unhash the dentry, rather just
298 * mark it inaccessible for to __d_lookup(). otherwise
299 * sys_getcwd() could return -ENOENT -bzzz */
300 dentry->d_flags |= DCACHE_LUSTRE_INVALID;
301 if (!dentry->d_inode || !S_ISDIR(dentry->d_inode->i_mode))
304 unlock_dentry(dentry);
308 void ll_unhash_aliases(struct inode *inode)
310 struct list_head *tmp, *head;
314 CERROR("unexpected NULL inode, tell phil\n");
318 CDEBUG(D_INODE, "marking dentries for ino %lu/%u(%p) invalid\n",
319 inode->i_ino, inode->i_generation, inode);
321 head = &inode->i_dentry;
322 cfs_spin_lock(&ll_lookup_lock);
323 spin_lock(&dcache_lock);
326 while ((tmp = tmp->next) != head) {
327 struct dentry *dentry = list_entry(tmp, struct dentry, d_alias);
329 CDEBUG(D_DENTRY, "dentry in drop %.*s (%p) parent %p "
330 "inode %p flags %d\n", dentry->d_name.len,
331 dentry->d_name.name, dentry, dentry->d_parent,
332 dentry->d_inode, dentry->d_flags);
334 if (dentry->d_name.len == 1 && dentry->d_name.name[0] == '/') {
335 CERROR("called on root (?) dentry=%p, inode=%p "
336 "ino=%lu\n", dentry, inode, inode->i_ino);
337 lustre_dump_dentry(dentry, 1);
338 libcfs_debug_dumpstack(NULL);
341 if (ll_drop_dentry(dentry))
344 spin_unlock(&dcache_lock);
345 cfs_spin_unlock(&ll_lookup_lock);
350 int ll_revalidate_it_finish(struct ptlrpc_request *request,
351 struct lookup_intent *it,
360 if (it_disposition(it, DISP_LOOKUP_NEG))
363 rc = ll_prep_inode(&de->d_inode, request, NULL);
368 void ll_lookup_finish_locks(struct lookup_intent *it, struct dentry *dentry)
371 LASSERT(dentry != NULL);
373 if (it->d.lustre.it_lock_mode && dentry->d_inode != NULL) {
374 struct inode *inode = dentry->d_inode;
375 struct ll_sb_info *sbi = ll_i2sbi(dentry->d_inode);
377 CDEBUG(D_DLMTRACE, "setting l_data to inode %p (%lu/%u)\n",
378 inode, inode->i_ino, inode->i_generation);
379 md_set_lock_data(sbi->ll_md_exp, &it->d.lustre.it_lock_handle,
383 /* drop lookup or getattr locks immediately */
384 if (it->it_op == IT_LOOKUP || it->it_op == IT_GETATTR) {
385 /* on 2.6 there are situation when several lookups and
386 * revalidations may be requested during single operation.
387 * therefore, we don't release intent here -bzzz */
388 ll_intent_drop_lock(it);
392 void ll_frob_intent(struct lookup_intent **itp, struct lookup_intent *deft)
394 struct lookup_intent *it = *itp;
396 if (!it || it->it_op == IT_GETXATTR)
401 int ll_revalidate_it(struct dentry *de, int lookup_flags,
402 struct lookup_intent *it)
404 struct md_op_data *op_data;
405 struct ptlrpc_request *req = NULL;
406 struct lookup_intent lookup_it = { .it_op = IT_LOOKUP };
407 struct obd_export *exp;
408 struct inode *parent = de->d_parent->d_inode;
412 CDEBUG(D_VFSTRACE, "VFS Op:name=%s,intent=%s\n", de->d_name.name,
415 if (de->d_inode == NULL) {
416 /* We can only use negative dentries if this is stat or lookup,
417 for opens and stuff we do need to query server. */
418 /* If there is IT_CREAT in intent op set, then we must throw
419 away this negative dentry and actually do the request to
420 kernel to create whatever needs to be created (if possible)*/
421 if (it && (it->it_op & IT_CREAT))
424 if (de->d_flags & DCACHE_LUSTRE_INVALID)
427 rc = ll_have_md_lock(parent, MDS_INODELOCK_UPDATE, LCK_MINMODE);
431 /* Never execute intents for mount points.
432 * Attributes will be fixed up in ll_inode_revalidate_it */
433 if (d_mountpoint(de))
434 GOTO(out_sa, rc = 1);
436 /* need to get attributes in case root got changed from other client */
437 if (de == de->d_sb->s_root) {
438 rc = __ll_inode_revalidate_it(de, it, MDS_INODELOCK_LOOKUP);
444 exp = ll_i2mdexp(de->d_inode);
446 OBD_FAIL_TIMEOUT(OBD_FAIL_MDC_REVALIDATE_PAUSE, 5);
447 ll_frob_intent(&it, &lookup_it);
450 if (it->it_op == IT_LOOKUP && !(de->d_flags & DCACHE_LUSTRE_INVALID))
451 GOTO(out_sa, rc = 1);
453 op_data = ll_prep_md_op_data(NULL, parent, de->d_inode,
454 de->d_name.name, de->d_name.len,
455 0, LUSTRE_OPC_ANY, NULL);
457 RETURN(PTR_ERR(op_data));
459 if ((it->it_op == IT_OPEN) && de->d_inode) {
460 struct inode *inode = de->d_inode;
461 struct ll_inode_info *lli = ll_i2info(inode);
462 struct obd_client_handle **och_p;
466 * We used to check for MDS_INODELOCK_OPEN here, but in fact
467 * just having LOOKUP lock is enough to justify inode is the
468 * same. And if inode is the same and we have suitable
469 * openhandle, then there is no point in doing another OPEN RPC
470 * just to throw away newly received openhandle. There are no
471 * security implications too, if file owner or access mode is
472 * change, LOOKUP lock is revoked.
476 if (it->it_flags & FMODE_WRITE) {
477 och_p = &lli->lli_mds_write_och;
478 och_usecount = &lli->lli_open_fd_write_count;
479 } else if (it->it_flags & FMODE_EXEC) {
480 och_p = &lli->lli_mds_exec_och;
481 och_usecount = &lli->lli_open_fd_exec_count;
483 och_p = &lli->lli_mds_read_och;
484 och_usecount = &lli->lli_open_fd_read_count;
486 /* Check for the proper lock. */
487 if (!ll_have_md_lock(inode, MDS_INODELOCK_LOOKUP, LCK_MINMODE))
489 cfs_down(&lli->lli_och_sem);
490 if (*och_p) { /* Everything is open already, do nothing */
491 /*(*och_usecount)++; Do not let them steal our open
492 handle from under us */
493 /* XXX The code above was my original idea, but in case
494 we have the handle, but we cannot use it due to later
495 checks (e.g. O_CREAT|O_EXCL flags set), nobody
496 would decrement counter increased here. So we just
497 hope the lock won't be invalidated in between. But
498 if it would be, we'll reopen the open request to
499 MDS later during file open path */
500 cfs_up(&lli->lli_och_sem);
501 ll_finish_md_op_data(op_data);
504 cfs_up(&lli->lli_och_sem);
508 if (it->it_op == IT_GETATTR)
509 first = ll_statahead_enter(parent, &de, 0);
512 it->it_create_mode &= ~cfs_curproc_umask();
513 it->it_create_mode |= M_CHECK_STALE;
514 rc = md_intent_lock(exp, op_data, NULL, 0, it,
516 &req, ll_md_blocking_ast, 0);
517 it->it_create_mode &= ~M_CHECK_STALE;
518 ll_finish_md_op_data(op_data);
519 if (it->it_op == IT_GETATTR && !first)
520 /* If there are too many locks on client-side, then some
521 * locks taken by statahead maybe dropped automatically
522 * before the real "revalidate" using them. */
523 ll_statahead_exit(parent, de, req == NULL ? rc : 0);
524 else if (first == -EEXIST)
525 ll_statahead_mark(parent, de);
527 /* If req is NULL, then md_intent_lock only tried to do a lock match;
528 * if all was well, it will return 1 if it found locks, 0 otherwise. */
529 if (req == NULL && rc >= 0) {
537 CDEBUG(D_INFO, "ll_intent_lock: rc %d : it->it_status "
538 "%d\n", rc, it->d.lustre.it_status);
544 rc = ll_revalidate_it_finish(req, it, de);
546 if (rc != -ESTALE && rc != -ENOENT)
547 ll_intent_release(it);
551 if ((it->it_op & IT_OPEN) && de->d_inode &&
552 !S_ISREG(de->d_inode->i_mode) &&
553 !S_ISDIR(de->d_inode->i_mode)) {
554 ll_release_openhandle(de, it);
558 /* unfortunately ll_intent_lock may cause a callback and revoke our
560 cfs_spin_lock(&ll_lookup_lock);
561 spin_lock(&dcache_lock);
565 d_rehash_cond(de, 0);
566 spin_unlock(&dcache_lock);
567 cfs_spin_unlock(&ll_lookup_lock);
570 /* We do not free request as it may be reused during following lookup
571 * (see comment in mdc/mdc_locks.c::mdc_intent_lock()), request will
572 * be freed in ll_lookup_it or in ll_intent_release. But if
573 * request was not completed, we need to free it. (bug 5154, 9903) */
574 if (req != NULL && !it_disposition(it, DISP_ENQ_COMPLETE))
575 ptlrpc_req_finished(req);
577 ll_unhash_aliases(de->d_inode);
578 /* done in ll_unhash_aliases()
579 dentry->d_flags |= DCACHE_LUSTRE_INVALID; */
581 CDEBUG(D_DENTRY, "revalidated dentry %.*s (%p) parent %p "
582 "inode %p refc %d\n", de->d_name.len,
583 de->d_name.name, de, de->d_parent, de->d_inode,
584 atomic_read(&de->d_count));
585 if (de->d_flags & DCACHE_LUSTRE_INVALID) {
587 de->d_flags &= ~DCACHE_LUSTRE_INVALID;
590 ll_lookup_finish_locks(it, de);
595 * This part is here to combat evil-evil race in real_lookup on 2.6
596 * kernels. The race details are: We enter do_lookup() looking for some
597 * name, there is nothing in dcache for this name yet and d_lookup()
598 * returns NULL. We proceed to real_lookup(), and while we do this,
599 * another process does open on the same file we looking up (most simple
600 * reproducer), open succeeds and the dentry is added. Now back to
601 * us. In real_lookup() we do d_lookup() again and suddenly find the
602 * dentry, so we call d_revalidate on it, but there is no lock, so
603 * without this code we would return 0, but unpatched real_lookup just
604 * returns -ENOENT in such a case instead of retrying the lookup. Once
605 * this is dealt with in real_lookup(), all of this ugly mess can go and
606 * we can just check locks in ->d_revalidate without doing any RPCs
610 if (it != &lookup_it) {
611 /* MDS_INODELOCK_UPDATE needed for IT_GETATTR case. */
612 if (it->it_op == IT_GETATTR)
613 lookup_it.it_op = IT_GETATTR;
614 ll_lookup_finish_locks(it, de);
618 /* Do real lookup here. */
619 op_data = ll_prep_md_op_data(NULL, parent, NULL, de->d_name.name,
620 de->d_name.len, 0, (it->it_op & IT_CREAT ?
622 LUSTRE_OPC_ANY), NULL);
624 RETURN(PTR_ERR(op_data));
626 rc = md_intent_lock(exp, op_data, NULL, 0, it, 0, &req,
627 ll_md_blocking_ast, 0);
629 struct mdt_body *mdt_body;
630 struct lu_fid fid = {.f_seq = 0, .f_oid = 0, .f_ver = 0};
631 mdt_body = req_capsule_server_get(&req->rq_pill, &RMF_MDT_BODY);
634 fid = *ll_inode2fid(de->d_inode);
636 /* see if we got same inode, if not - return error */
637 if (lu_fid_eq(&fid, &mdt_body->fid1)) {
638 ll_finish_md_op_data(op_data);
640 goto revalidate_finish;
642 ll_intent_release(it);
644 ll_finish_md_op_data(op_data);
649 * For rc == 1 case, should not return directly to prevent losing
650 * statahead windows; for rc == 0 case, the "lookup" will be done later.
652 if (it && it->it_op == IT_GETATTR && rc == 1) {
653 first = ll_statahead_enter(parent, &de, 0);
655 ll_statahead_exit(parent, de, 1);
656 else if (first == -EEXIST)
657 ll_statahead_mark(parent, de);
663 int ll_revalidate_nd(struct dentry *dentry, struct nameidata *nd)
668 if (nd && !(nd->flags & (LOOKUP_CONTINUE|LOOKUP_PARENT))) {
669 struct lookup_intent *it;
671 it = ll_convert_intent(&nd->intent.open, nd->flags);
675 if (it->it_op == (IT_OPEN|IT_CREAT) &&
676 nd->intent.open.flags & O_EXCL) {
677 CDEBUG(D_VFSTRACE, "create O_EXCL, returning 0\n");
682 rc = ll_revalidate_it(dentry, nd->flags, it);
684 if (rc && (nd->flags & LOOKUP_OPEN) &&
685 it_disposition(it, DISP_OPEN_OPEN)) {/*Open*/
686 #ifdef HAVE_FILE_IN_STRUCT_INTENT
687 // XXX Code duplication with ll_lookup_nd
688 if (S_ISFIFO(dentry->d_inode->i_mode)) {
689 // We cannot call open here as it would
692 (struct ptlrpc_request *)
693 it->d.lustre.it_data);
695 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,17))
696 /* 2.6.1[456] have a bug in open_namei() that forgets to check
697 * nd->intent.open.file for error, so we need to return it as lookup's result
701 nd->intent.open.file->private_data = it;
702 filp = lookup_instantiate_filp(nd, dentry,NULL);
707 nd->intent.open.file->private_data = it;
708 (void)lookup_instantiate_filp(nd, dentry,NULL);
712 ll_release_openhandle(dentry, it);
713 #endif /* HAVE_FILE_IN_STRUCT_INTENT */
715 if (!rc && (nd->flags & LOOKUP_CREATE) &&
716 it_disposition(it, DISP_OPEN_CREATE)) {
717 /* We created something but we may only return
718 * negative dentry here, so save request in dentry,
719 * if lookup will be called later on, it will
720 * pick the request, otherwise it would be freed
722 ll_d2d(dentry)->lld_it = it;
723 it = NULL; /* avoid freeing */
728 ll_intent_release(it);
729 OBD_FREE(it, sizeof(*it));
732 rc = ll_revalidate_it(dentry, 0, NULL);
738 void ll_d_iput(struct dentry *de, struct inode *inode)
741 if (!find_cbdata(inode))
746 struct dentry_operations ll_d_ops = {
747 .d_revalidate = ll_revalidate_nd,
748 .d_release = ll_release,
749 .d_delete = ll_ddelete,
751 .d_compare = ll_dcompare,